1
|
Sun SY, Gaertner W, Reynolds MA. Outcomes of Watch and Wait Following Total Neoadjuvant Therapy for Rectal Cancer. Int J Radiat Oncol Biol Phys 2023; 117:e340. [PMID: 37785191 DOI: 10.1016/j.ijrobp.2023.06.2401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) To evaluate the outcomes of patients with locally advanced rectal cancer who achieved a clinical complete response (cCR) after total neoadjuvant therapy and enrolled in a prospective watch and wait (WW) database. MATERIALS/METHODS Consecutive patients with locally advanced rectal cancer who achieved cCR following total neoadjuvant therapy (long-course chemoradiotherapy plus systemic chemotherapy) and were enrolled in our institutional WW surveillance protocol from 2014 through 2022 with the intention of organ preservation. Patients with lack of follow up according to our institutional protocol were excluded. Primary outcomes included local tumor regrowth and distant metastatic disease recurrence. RESULTS Thirty-three consecutive patients (48% male; median age 61 [33-77] years) with the diagnosis of locally advanced rectal adenocarcinoma were managed by a multidisciplinary team. All patients had Eastern Cooperative Oncology Group Performance Status score of 0 or 1 at time of rectal cancer diagnosis. Location of tumor included upper rectum (18%), middle rectum (40%), and lower rectum (42%). On initial staging magnetic resonance imaging, 4 (12%) patients had evidence of extramural venous invasion, 6 (18%) had a threatened mesorectal margin, and 4 (12%) had anal sphincter or levator ani tumor involvement. A majority (61%) received chemotherapy followed by long-course chemoradiotherapy. Only one patient had an unplanned break during radiotherapy. Local tumor regrowth was diagnosed in 4 (12%) patients and all underwent successful salvage surgery without additional local failures at a median follow-up of 19 [12-48] months. Two of these four patients remain disease-free at a median follow-up time of 12.5 months. Mean time to local tumor regrowth as first site of cancer recurrence was 33.5 [18-46] months. Distant metastatic disease as the first site of recurrence occurred two patients (6%). Mean time to distant metastatic disease as first site of recurrence was 27 months. Only one mortality occurred in the entire group at a median follow-up of 49 [8-102] months. CONCLUSION Organ preservation after total neoadjuvant therapy for locally advanced rectal cancer yields excellent outcomes with low local and distant relapse rates. Structured surveillance protocols and multidisciplinary care are essential for success.
Collapse
Affiliation(s)
- S Y Sun
- University of Minnesota, Minneapolis, MN
| | - W Gaertner
- University of Minnesota, Minneapolis, MN
| | - M A Reynolds
- Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN
| |
Collapse
|
2
|
Wanhainen K, Berkseth M, Sando N, Golden L, Techam A, Wieworka J, Bergerud KB, Argenta P, O'Shea A, Rivard C, Ghebre R, Teoh D, Reynolds MA, Terezakis SA, Yuan J, Sloan L. Effect of External Beam Radiation Therapy (EBRT) and Brachytherapy (BT) on Circulating MDSC Populations in Patients Treated Definitively for Cervical Cancer. Int J Radiat Oncol Biol Phys 2023; 117:e554. [PMID: 37785703 DOI: 10.1016/j.ijrobp.2023.06.1864] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/04/2023]
Abstract
PURPOSE/OBJECTIVE(S) The immunosuppressive function of myeloid derived suppressor cells (MDSCs) has been implicated in the regulation of immune responses against cancer. MDSCs have been associated with progression and poor response to therapy in various types of cancer, including cervical cancer. Radiation treatment (RT) alters immune cell populations within the tumor and is thought to augment antitumor responses. However, whether RT also recruits immunosuppressive MDSC populations is not well understood. Here, we investigate how circulating MDSC populations change in response to RT and if changes in MDSC frequency or subsets is predictive of RT responses in cervical cancer patients. MATERIALS/METHODS Newly diagnosed, treatment-naïve pts with locally advanced carcinoma of the cervix will be enrolled from July 2022 to July 2023. EBRT to the pelvis was delivered at a dose of 45 Gy in 25 fractions with a simultaneous integrated boost of 52-55 Gy to involved regional lymph nodes and parametria and concurrent weekly cisplatin. Gross tumor was boosted via interstitial or tandem ring BT (22.5-27.5 Gy) after completion of EBRT. Serial blood samples were collected prior to initiating therapy (T0), post-EBRT and pre-BT (T1), and one-month post-BT (T2). Treatment response was determined based on pre-treatment MRI compared to MRI post-EBRT. Peripheral blood mononuclear cells (PBMCs) were isolated from whole blood using density gradient centrifugation and stained for analysis via flow cytometry. MDSC populations were identified by Live/Dead-CD11b+CD33+HLA-DR- staining. MDSC subsets were further subdivided into granulocytic (G-, CD15+CD14-), monocytic (M-, CD15-CD14+), or early-MDSCs (e-, CD15-CD14-). RESULTS Blood samples were collected at indicated time points for four patients (FIGO stage IIA-IIB). Three had partial responses to chemoradiotherapy (CRT), while one had a complete response. All three patients with partial response had an increase in total frequency of circulating MDSCs in response to EBRT/BT (mean %fx MDSC 16.6 at T0 to 35.9 at T2), and an increase in total MDSCs in two of these patients occurred with EBRT alone. Interestingly, the patient that had a complete response had fewer MDSCs at T2 relative to T0 (35.8% at T0 to 27% at T2). Proportion of MDSC subsets varied considerably among the patients, and all had altered distribution of subsets in response to RT. G-MDSCs expanded the most to RT while M-MDSCs and e-MDSCs were less affected (mean fold change from T0 to T2 G-MDSC 4.75, M-MDSC 1.27, e-MDSC 0.942). CONCLUSION In this cohort of patients, an increase in MDSC frequency occurred after RT and altered subset distribution. Only the patient with a complete response had fewer total MDSCs following completion of CRT, suggesting further studies are needed to determine if circulating MDSCs could be a biomarker for treatment response to RT in cervical cancer.
Collapse
Affiliation(s)
- K Wanhainen
- University of Minnesota Medical School, Minneapolis, MN
| | - M Berkseth
- University of Minnesota, Minneapolis, MN
| | - N Sando
- University of Minnesota, Minneapolis, MN
| | - L Golden
- University of Minnesota, Minneapolis, MN
| | - A Techam
- M Health Fairview, Minneapolis, MN
| | | | | | - P Argenta
- University of Minnesota Medical School, Minneapolis, MN
| | - A O'Shea
- University of Minnesota Medical School, Minneapolis, MN
| | - C Rivard
- University of Minnesota Medical School, Minneapolis, MN
| | - R Ghebre
- University of Minnesota Medical School, Minneapolis, MN
| | - D Teoh
- University of Minnesota Medical School, Minneapolis, MN
| | - M A Reynolds
- Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN
| | | | - J Yuan
- Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN
| | - L Sloan
- Department of Radiation Oncology, University of Minnesota Medical School, Minneapolis, MN
| |
Collapse
|
3
|
Leão TSS, Tomasi GH, Conzatti LP, Marrone LCP, Reynolds MA, Gomes MS. Oral inflammatory burden and carotid atherosclerosis among stroke patients. J Endod 2022; 48:597-605. [PMID: 35143813 DOI: 10.1016/j.joen.2022.01.019] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Revised: 01/28/2022] [Accepted: 01/30/2022] [Indexed: 12/26/2022]
Abstract
INTRODUCTION This study aimed to test the hypothesis that oral inflammatory burden (OIB) is independently associated with the carotid atherosclerotic burden (CAB) among individuals with ischemic stroke (IS) or transient ischemic attack (TIA). METHODS This cross-sectional observational study included 240 hospital patients with the diagnosis of IS or TIA. The main exposures were apical periodontitis (AP), root canal treatment (RCT), and crestal alveolar (periodontal) bone loss (BL), and the main outcome was the CAB. Exposure and outcome variables were measured through a head and neck multidetector computed tomography angiography and CAB was dichotomized in <50% and ≥50% vessel occlusion. OIB scored as a composite measure of the endodontic and periodontal disease exposure. Hospital health records provided information on socio-demographic and medical covariates. Prevalence ratios (PR) were calculated through Poisson regression models, estimating the relationship between the oral exposures and CAB, with =5%. RESULTS Mean age was 62.15 ± 13.1 years, with 56.7% males. Univariate analyses showed that AP≥2 (PR=1.83,95%CI=1.05-3.17) and endodontic burden (EB) (AP &/or RCT≥2) (PR=1.98,95%CI=1.13-3.47) were associated with CAB ≥50%. Multivariate models, adjusted for socio-demographic and medical covariates, revealed that pooled periodontal and endodontic parameters (OIB= BL ≥5mm & EB ≥2) was independently associated with CAB ≥50% (PR=2.47,95%CI= 1.04-5.87). CONCLUSION A higher OIB was independently associated with increased levels of CAB among IS or TIA hospital patients. The combination of endodontic and periodontal parameters strengthened the observed association and should be evaluated in future studies on the relationship between oral health and cardiovascular outcomes.
Collapse
Affiliation(s)
- T S S Leão
- Graduate Program in Dentistry, School of Health and Life Sciences, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil;; Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - G H Tomasi
- Department of Neurology, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - L P Conzatti
- Department of Neurology, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - L C P Marrone
- Department of Neurology, Hospital São Lucas, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - M A Reynolds
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD 21201, USA
| | - M S Gomes
- Graduate Program in Dentistry, School of Health and Life Sciences, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, RS, Brazil;; Medical and Dental Center of the Military Police of Rio Grande do Sul, Brazil
| |
Collapse
|
4
|
Postolache TT, Wadhawan A, Daue ML, Dagdag A, Reynolds MA. 1061 Problems During Daytime Due To Poor Sleep Are Associated With Indicators Of Poor Dental Health In A Largely Non-smoking Population. Sleep 2020. [DOI: 10.1093/sleep/zsaa056.1057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Abstract
Introduction
Growing evidence connects periodontal disease, a major and modifiable cause of local and systemic inflammation, with metabolic and cardiovascular morbidity and mortality, as well as mental illness. Sleep has been previously predictively associated with metabolic and psychiatric morbidity and mortality, and has recently been linked with periodontal disease. We are now evaluating associations between self-reported insomnia measures and surrogate indicators of periodontal disease in a population with a very low prevalence of smoking — a major confounder in previous studies.
Methods
Dental and sleep questionnaires (Pittsburgh Sleep Quality Index) were obtained from 3881 Old Order Amish from Lancaster county. Difficulty falling or staying asleep, sleep quality, problems during the day due to poor sleep, and sleepiness during daytime were related to self-reported loose teeth, partial dentures, full dentures and any dentures using linear models with adjustment for age and sex.
Results
Significant associations emerged between problems falling asleep and loose teeth (p<0.05), problems staying asleep and any dentures (p<0.05), sleep quality with loose teeth and partial, as well as complete dentures (p<0.05 for both). Problems during daytime due to poor sleep were associated with loose teeth (p<0.05), any dentures (p<0.003) and full dentures (p<0.0001 — the only associations resisting Bonferroni correction). Sleepiness during daytime, which is the most important marker associated with sleep apnea was not associated with any dental health measures.
Conclusion
Limitations include not accounting for family aggregation, limited generalizability, not fully differentiating between respiratory versus non-respiratory sleep impairment, and periodontal versus traumatic dental pathology. Yet, the results of our study, which minimizes the strong potential confounding by smoking, confirm associations between sleep-related problems and periodontal disease, and justify future longitudinal and interventional research to dissect causality and identify multi-target treatment modalities.
Support
This work was supported by the Mid-Atlantic Nutrition Obesity Research Center Preliminary Developmental NORC grant (Postolache, PI), a sub-award of the parent grant P30 DK072488 (Mitchell, PI), and intramural funds from the University of Maryland, Baltimore.
Collapse
Affiliation(s)
- T T Postolache
- Mood and Anxiety Program, University of Maryland School of Medicine, Baltimore, MD
- Rocky Mountain Mental Illness Research Education and Clinical Center (MIRECC), Veterans Integrated Service Network (VISN) 19, Military and Veteran Microbiome Consortium for Research and Education (MVM-CoRE), Denver, CO
- Mental Illness Research, Education and Clinical Center (MIRECC), Veterans Integrated Service Network (VISN) 5, VA Capitol Health Care Network, Baltimore, MD
| | - A Wadhawan
- Mood and Anxiety Program, University of Maryland School of Medicine, Baltimore, MD
- Saint Elizabeth’s Hospital, Department of Psychiatry, Washington, DC
| | - M L Daue
- Division of Endocrinology, Diabetes and Nutrition, Department of Medicine, University of Maryland School of Medicine, Baltimore, MD
- Program for Personalized and Genomic Medicine, University of Maryland School of Medicine, Baltimore, MD
- Geriatrics Research and Education Clinical Center, Veterans Affairs Medical Center, Baltimore, MD
| | - A Dagdag
- Mood and Anxiety Program, University of Maryland School of Medicine, Baltimore, MD
| | - M A Reynolds
- Department of Advanced Oral Sciences & Therapeutics, University of Maryland School of Dentistry, Baltimore, MD
| |
Collapse
|
5
|
Reynolds MA, Borchers MR, Davidson JA, Bradley CM, Bewley JM. Technical note: An evaluation of technology-recorded rumination and feeding behaviors in dairy heifers. J Dairy Sci 2019; 102:6555-6558. [PMID: 31128868 DOI: 10.3168/jds.2018-15635] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2018] [Accepted: 03/19/2019] [Indexed: 11/19/2022]
Abstract
Precision dairy monitoring technologies have become increasingly popular for recording rumination and feeding behaviors in dairy cattle. The objective of this study was to validate the rumination and feeding time functions of the CowManager SensOor (Agis, Harmelen, the Netherlands) against visual observation in dairy heifers. The study took place over a 44-d period beginning June 1, 2016. Holstein heifers equipped with CowManager SensOor tags attached according to manufacturer specifications (n = 49) were split into 2 groups based on age, diet, and housing type. Group 1 heifers (n = 24) were calves (mean ± SD) 2.0 ± 2.7 mo in age, fed hay and calf starter, and housed on a straw-bedded pack. Group 2 heifers (n = 25) were 17.0 ± 1.3 mo in age, fed a TMR, confirmed pregnant, and housed in freestalls. Visual observation shifts occurred at 1500, 1700, 1900, and 2100 h. Each heifer was observed for 2 hour-long periods, with both observation periods occurring on the same day. Visual observations were collected using a synchronized watch, and "start" and "stop" times were recorded for each rumination and feeding event. For correlations, data from CowManager SensOor tags and observations were averaged, so a single 1-h observation was provided per animal, reducing the potential for confounding repeated measures being collected for each animal. Concordance correlations (CCC; epiR package; R Foundation for Statistical Computing, Vienna, Austria) and Pearson correlations (r; CORR procedure; SAS Institute Inc., Cary, NC) were used to calculate association between visual observations and technology-recorded behaviors. Visually observed rumination time was correlated with the CowManager SensOor (r = 0.63, CCC = 0.55). Visually observed feeding time was also correlated with the CowManager SensOor (r = 0.88, CCC = 0.72). The difference between technology-recorded data and visual observation was treated as the dependent variable in a mixed linear model (MIXED procedure of SAS). Time of day, age in months, and group were treated as fixed effects. Individual heifers were treated as random and repeated effects. The effects of time of day, age, and group on rumination and feeding times were not significant. The CowManager SensOor was more effective at recording feeding behavior than rumination behavior in dairy heifers. The CowManager SensOor can be used to provide relatively accurate measures of feeding time in heifers, but its rumination time function should be used with caution.
Collapse
Affiliation(s)
- M A Reynolds
- Department of Animal and Food Sciences, University of Kentucky, Lexington 40546; Department of Animal Science, University of Nebraska-Lincoln, Lincoln 68527; Purina Animal Nutrition Center, Gray Summit, MO 63039
| | - M R Borchers
- Department of Animal and Food Sciences, University of Kentucky, Lexington 40546.
| | - J A Davidson
- Purina Animal Nutrition Center, Gray Summit, MO 63039
| | - C M Bradley
- Purina Animal Nutrition Center, Gray Summit, MO 63039
| | - J M Bewley
- Department of Animal and Food Sciences, University of Kentucky, Lexington 40546; Alltech Inc., Nicholasville, KY 40356
| |
Collapse
|
6
|
Erchick DJ, Rai B, Agrawal NK, Khatry SK, Katz J, LeClerq SC, Reynolds MA, Mullany LC. Oral hygiene, prevalence of gingivitis, and associated risk factors among pregnant women in Sarlahi District, Nepal. BMC Oral Health 2019; 19:2. [PMID: 30611255 PMCID: PMC6321675 DOI: 10.1186/s12903-018-0681-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 11/27/2018] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The oral health status of pregnant women in low-resource communities such as Nepal has not been well characterized. This sub-population is also of specific interest given associations between poor oral health and adverse pregnancy outcomes previously documented in other settings. We explored relationships between gingivitis and risk factors among pregnant women in rural Nepal. METHODS The design was a community-based, cross-sectional study in a sub-area of Sarlahi District, Nepal. Pregnant women < 26 weeks gestation underwent clinical periodontal exams conducted by community-based oral health workers. Exams included a full mouth assessment measuring bleeding on probing (BOP), probing depth (PD) (six sites per tooth), and gingival recession, the distance from the cemento-enamel junction to the free gingival margin (two direct sites per tooth). Data on participant risk factors were collected through household surveys, including demographic characteristics, oral health behaviors, care seeking, and health attitudes. Multivariable logistic regression modeling was used to assess relationships between gingivitis and risk factors. RESULTS We enrolled 1452 participants, of which 40% (n = 582) had signs of clinical gingivitis and 60% (n = 870) clinical health. Average participant age was 23. Most participants (88%) had never received oral health care. Participants averaged 10% of sites with BOP with most (79%) having ≥1 site with BOP. Nine percent of participants had ≥1 site with PD ≥4 mm, although very few participants (0.7%) had sites with PD ≥5 mm. Few participants (13%) had any recession (≥1 mm). In the final adjusted model, odds of gingivitis increased by 3% for each year of age (aOR 1.03, 95% CI 1.00, 1.06) and were higher for women of short maternal stature (< 150 cm) (aOR 1.43, 95% CI: 1.14, 1.79) and among women reporting cost to be a barrier to seeking dental care (aOR 2.13, 95% CI: 1.09, 4.15). CONCLUSIONS Gingivitis was common and associated with age, maternal stature, self-reported high cost of dental care, and other risk factors among pregnant women in rural Nepal. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01177111 (Nepal Oil Massage Study) and NCT02788786 (Pilot Trial).
Collapse
Affiliation(s)
- D. J. Erchick
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
| | - B. Rai
- Nepal Nutrition Intervention Project, Sarlahi (NNIPS), Krishna Galli, Lalitpur, Kathmandu Nepal
| | - N. K. Agrawal
- Department of Dentistry, Institute of Medicine, Tribhuhvan University, Kathmandu, Nepal
| | - S. K. Khatry
- Nepal Nutrition Intervention Project, Sarlahi (NNIPS), Krishna Galli, Lalitpur, Kathmandu Nepal
| | - J. Katz
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
| | - S. C. LeClerq
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
- Nepal Nutrition Intervention Project, Sarlahi (NNIPS), Krishna Galli, Lalitpur, Kathmandu Nepal
| | - M. A. Reynolds
- Department of Advanced Oral Sciences and Therapeutics, University of Maryland School of Dentistry, Baltimore, MD USA
| | - L. C. Mullany
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, MD USA
| |
Collapse
|
7
|
Reynolds MA, Brown-Brandl TM, Judy JV, Herrick KJ, Hales KE, Watson AK, Kononoff PJ. Use of indirect calorimetry to evaluate utilization of energy in lactating Jersey dairy cattle consuming common coproducts. J Dairy Sci 2019; 102:320-333. [PMID: 30343910 DOI: 10.3168/jds.2018-15471] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2018] [Accepted: 09/04/2018] [Indexed: 12/17/2023]
Abstract
The use of coproducts as an alternative feed source is a common practice when formulating dairy rations. A study using 12 multiparous (79 ± 16 d in milk; mean ± standard deviation) lactating Jersey cows was conducted over 5 mo to evaluate the effects of dried distillers grains with solubles (DDGS) or canola meal on milk and gas production. A replicated 4 × 4 Latin square design was used to compare 4 dietary treatments. Treatments comprised a control (CON) containing no coproducts, a treatment diet containing 10% (dry matter basis) low-fat DDGS (LFDG), a treatment diet containing 10% high-fat DDGS (HFDG), and a 10% canola meal (CM) treatment. The crude fat content of the LFDG, HFDG, and CM treatments was 6.05 ± 0.379, 10.0 ± 0.134, and 3.46 ± 0.085%, respectively. Coproducts were included in partial replacement for corn and soybean meal. Indirect headbox-style calorimeters were used to estimate heat production. Dry matter intake and milk yield were similar between all treatments, averaging 17.4 ± 0.56 kg/d and 24.0 ± 0.80 kg, respectively. Milk urea N was affected by treatment and was highest in CON (20.6 mg/dL; 18.0, 19.9, and 18.1 ± 0.62 mg/dL in LFDG, CM, and HFDG, respectively). Heat production per unit of metabolic body weight tended to be affected by treatment and was lowest for CON, and diets containing coproducts were not different (192, 200, 215, and 204 ± 5.91 kcal/kg of metabolic body weight for CON, LFDG, CM, and HFDG, respectively). The concentration of metabolizable energy was affected by dietary treatment; specifically, HFDG did not differ from CON but was greater than LFDG and CM (2.58, 2.46, 2.29, and 2.27 ± 0.09 Mcal/kg for HFDG, CON, LFDG, and CM, respectively). The concentration of net energy balance (milk plus tissue) tended to be affected by dietary treatment; HFDG did not differ from either CON or LFDG, but it was higher than CM (1.38, 1.36, 1.14, and 1.06 ± 0.11 Mcal/kg for HFDG, CON, LFDG, and CM, respectively). Results of this study indicate that milk production and dry matter intake were not affected by feeding common coproducts and that differences may result in whole-animal energy use; fat content of DDGS is a major factor affecting this.
Collapse
Affiliation(s)
- M A Reynolds
- Department of Animal Science, University of Nebraska-Lincoln, Lincoln 68583-0908
| | - T M Brown-Brandl
- USDA Agricultural Research Service, US Meat Animal Research Center, Clay Center, NE 68818
| | - J V Judy
- Department of Animal Science, University of Nebraska-Lincoln, Lincoln 68583-0908
| | | | - K E Hales
- USDA Agricultural Research Service, US Meat Animal Research Center, Clay Center, NE 68818
| | - A K Watson
- Department of Animal Science, University of Nebraska-Lincoln, Lincoln 68583-0908
| | - P J Kononoff
- Department of Animal Science, University of Nebraska-Lincoln, Lincoln 68583-0908.
| |
Collapse
|
8
|
Costello LC, Franklin RB, Reynolds MA. The Important Role and Implications of Citrate in the Composition, Structure, and Function of Oral/Periodontal/Craniofacial Tissues. ACTA ACUST UNITED AC 2018; 3:85-90. [PMID: 30906931 PMCID: PMC6426309 DOI: 10.18689/mjdl-1000120] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
High citrate concentration is a major component in the structure of craniofacial bone, teeth and periodontal tissues of humans and other osteovertebrates. It is now established that citrate incorporation into the apatite/collagen complex of bone is essential for the manifestation of the important biomechanical properties of bone; such as stability, strength, and resistance to fracture. The osteoblasts are specialized citrate-producing cells that provide the citrate incorporated in bone during osteogenic stem cell differentiation for production of new bone; “citration” that occurs in concert with mineralization. Dentin and cementum contain high citrate levels; as contrasted with low citrate in enamel. There exists no information regarding the status and source of incorporated citrate in dentin or in cementum. These are important issues relating to oral, periodontal, craniofacial structures. For example, repair of defects should include new tissue that exhibits the composition, structure, and biomechanical properties of the “normal” tissue; which cannot be achieved in the absence of citrate incorporation in the new tissues. Unfortunately, the presence and role of citrate in these tissues have been largely ignored and unrecognized over the past about 40 years by the dental and medical community. The intent of this review is to re-establish the interest and research regarding the important citrate relationships and issues; with focus on related interests in dentistry.
Collapse
Affiliation(s)
- L C Costello
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland; and the University of Maryland Greenebaum Cancer Center, Baltimore, Md. 21201
| | - R B Franklin
- Department of Oncology and Diagnostic Sciences, School of Dentistry, University of Maryland; and the University of Maryland Greenebaum Cancer Center, Baltimore, Md. 21201
| | - M A Reynolds
- Office of the Dean of the School of Dentistry, University of Maryland, Baltimore, Md. 21201
| |
Collapse
|
9
|
Lubon AJ, Erchick DJ, Khatry SK, LeClerq SC, Agrawal NK, Reynolds MA, Katz J, Mullany LC. Oral health knowledge, behavior, and care seeking among pregnant and recently-delivered women in rural Nepal: a qualitative study. BMC Oral Health 2018; 18:97. [PMID: 29859084 PMCID: PMC5984796 DOI: 10.1186/s12903-018-0564-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/27/2017] [Accepted: 05/23/2018] [Indexed: 10/25/2022] Open
Abstract
BACKGROUND Oral health behavior and attitudes of pregnant women in low-income countries are rarely examined, yet should be considered when designing preventative or therapeutic studies to reduce burden of oral diseases. We aimed to understand dental care-seeking behavior, as well as oral health knowledge and attitudes of oral health among pregnant women in rural Nepal. METHODS Semi-structured in-depth interviews (n = 16) and focus group discussions (3 groups, n = 23) were conducted among pregnant and recently-delivered women in Sarlahi, Nepal. Transcripts were translated from the local language to English then analyzed using a hybrid approach to thematic coding with Atlas.ti version 7. RESULTS Women felt confident describing the signs and symptoms of tooth decay and gum disease, but were not knowledgeable about where to receive care for tooth and/or gum pain and relied heavily on the knowledge of their community. Some women used a toothbrush and toothpaste at least once a day to clean their teeth, but many reported the traditional use of a branch of a local shrub or tree as their teeth cleaning instrument. Women suggested a willingness to consider using an oral rinse throughout pregnancy, perceiving that it might have a positive impact on infant health. CONCLUSIONS Future studies should focus on providing adequate and sustainable resources for pregnant women in Nepal and other low income settings to engage in good oral health behaviors (possibly supported through community-based workers), to maintain dental hygiene, and to access qualified dentists as a means of improving their oral health. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT01177111 (Nepal Oil Massage Study) and NCT02788786 (Pilot Trial).
Collapse
Affiliation(s)
- A. J. Lubon
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street W5009, Baltimore, MD 21205 USA
| | - D. J. Erchick
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street W5009, Baltimore, MD 21205 USA
| | - S. K. Khatry
- Nepal Nutrition Intervention Project – Sarlahi (NNIPS), Krishna Galli, Lalitpur, Kathmandu Nepal
| | - S. C. LeClerq
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street W5009, Baltimore, MD 21205 USA
- Nepal Nutrition Intervention Project – Sarlahi (NNIPS), Krishna Galli, Lalitpur, Kathmandu Nepal
| | - N. K. Agrawal
- Department of Dentistry, Institute of Medicine, Tribhuhvan University, Kathmandu, Nepal
| | - M. A. Reynolds
- Department of Periodontics, University of Maryland School of Dentistry, Baltimore, MD USA
| | - J. Katz
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street W5009, Baltimore, MD 21205 USA
| | - L. C. Mullany
- Department of International Health, Johns Hopkins Bloomberg School of Public Health, 615 N. Wolfe Street W5009, Baltimore, MD 21205 USA
| |
Collapse
|
10
|
Cheng L, Zhang K, Zhang N, Melo MAS, Weir MD, Zhou XD, Bai YX, Reynolds MA, Xu HHK. Developing a New Generation of Antimicrobial and Bioactive Dental Resins. J Dent Res 2017; 96:855-863. [PMID: 28530844 DOI: 10.1177/0022034517709739] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Dental caries is prevalent, and secondary caries causes restoration failures. This article reviews recent studies on developing a new generation of bioactive resins with anticaries properties. Extensive effects were made to develop new antimicrobial composites, bonding agents, and other resins containing quaternary ammonium methacrylates to suppress plaque buildup and bacterial acid production. The effects of alkyl chain length and charge density and the antimicrobial mechanisms for chlorhexidine, nano-silver, quaternary ammonium methacrylates, and protein-repellent agents were discussed. Synergistic effects of contact-killing and protein-repellent properties were shown to yield the greatest biofilm-inhibition effects. The combination of antimicrobial, protein-repellent, and calcium phosphate nanoparticle remineralization was suggested to provide maximal anticaries effects. In addition, for use orally, cytotoxicity and biocompatibility were important considerations for the new bioactive materials. Furthermore, rather than kill all bacteria, it would be more desirable to modulate the oral biofilm compositions via bioactive resins to suppress cariogenic/pathogenic species and promote benign species. For widespread clinical use of the new antimicrobial and therapeutic materials, whether they would induce bacterial drug resistance needs to be determined, which requires further study. Nonetheless, the new generation of bioactive anticaries resins with therapeutic and biofilm acid-inhibiting properties has the potential to substantially benefit oral health.
Collapse
Affiliation(s)
- L Cheng
- 1 State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China.,2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA
| | - K Zhang
- 2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA.,3 Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - N Zhang
- 2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA.,3 Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - M A S Melo
- 2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA
| | - M D Weir
- 2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA
| | - X D Zhou
- 1 State Key Laboratory of Oral Diseases, West China Hospital of Stomatology, Sichuan University, Chengdu, China
| | - Y X Bai
- 3 Department of Orthodontics, School of Stomatology, Capital Medical University, Beijing, China
| | - M A Reynolds
- 2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA
| | - H H K Xu
- 2 Department of Endodontics, Periodontics, and Prosthodontics, University of Maryland Dental School, Baltimore, MD, USA.,4 Center for Stem Cell Biology & Regenerative Medicine, University of Maryland School of Medicine, Baltimore, MD, USA.,5 Marlene and Stewart Greenebaum Cancer Center, University of Maryland School of Medicine, Baltimore, MD, USA.,6 Department of Mechanical Engineering, University of Maryland, Baltimore County, MD, USA
| |
Collapse
|
11
|
Reynolds MA. Association of British Insurers. Int J STD AIDS 2016. [DOI: 10.1177/095646249400500504] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Affiliation(s)
- M A Reynolds
- Medical Advisor Association of British Insurers 51 Gresham Street, London EC2V 7HQ
| |
Collapse
|
12
|
Gomes MS, Hugo FN, Hilgert JB, Sant'Ana Filho M, Padilha DMP, Simonsick EM, Ferrucci L, Reynolds MA. Apical periodontitis and incident cardiovascular events in the Baltimore Longitudinal Study of Ageing. Int Endod J 2015; 49:334-42. [PMID: 26011008 DOI: 10.1111/iej.12468] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2014] [Accepted: 05/18/2015] [Indexed: 12/19/2022]
Abstract
AIM To evaluate whether the presence of apical periodontitis (AP), root canal treatment (RCT) and endodontic burden (EB) - as the sum of AP and RCT sites - were associated with long-term risk of incident cardiovascular events (CVE), including cardiovascular-related mortality, using data on participants in the Baltimore Longitudinal Study of Ageing (BLSA). METHODOLOGY This retrospective cohort included 278 dentate participants in the BLSA with complete medical and dental examinations. Periodontal disease (PD) and missing teeth were recorded. The total number of AP and RCT sites was determined from panoramic radiographs. EB was calculated as the sum of AP and RCT sites. Oral inflammatory burden (OIB) was calculated combining PD and EB. The main outcome was incident CVE including angina, myocardial infarction and cardiovascular-related death. Participants were monitored for up to 44 years (mean = 17.4± 11.1 years) following dental examination. Relative risks (RRs) were calculated through Poisson regression models, estimating the relationship between AP, RCT, EB, PD, OIB and incident CVE. RESULTS Mean age at baseline was 55.0 ±16.8 years and 51.4% were men. Sixty-two participants (22.3%) developed CVE. Bivariate analysis showed that PD, EB, number of teeth and OIB were associated with incident CVE. Multivariate models, adjusted for socio-demographic and medical variables, showed that age ≥60 years (RR = 3.07, 95% CI =1.68-5.62), hypertension (RR = 2.0, 95% CI = 1.16-3.46) and EB ≥3 (RR = 1.77, 95% CI = 1.04-3.02) were independently associated with incident CVE. The association between OIB and incident CVE was reduced to nonsignificance after adjustments (RR = 1.97, 95% CI = 0.83-4.70). CONCLUSIONS EB in midlife was an independent predictor of CVE amongst community-dwelling participants in the BLSA. Prospective studies are required to evaluate cardiovascular risk reduction with the treatment of AP.
Collapse
Affiliation(s)
- M S Gomes
- Medical and Dental Center of the Military Police of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - F N Hugo
- Department of Community Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - J B Hilgert
- Department of Community Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - M Sant'Ana Filho
- Postgraduate Program, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - D M P Padilha
- Department of Community Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - E M Simonsick
- National Institute on Aging, Translational Gerontology Branch, Intramural Research Program, Baltimore, MD, USA
| | - L Ferrucci
- National Institute on Aging, Translational Gerontology Branch, Intramural Research Program, Baltimore, MD, USA
| | - M A Reynolds
- Department of Periodontics, School of Dentistry, University of Maryland, Baltimore, MD, USA
| |
Collapse
|
13
|
Bogard DD, Clark RS, Keith JE, Reynolds MA. Noble gases and radionuclides in Lost City and other recently fallen meteorites. ACTA ACUST UNITED AC 2012. [DOI: 10.1029/jb076i017p04076] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
|
14
|
|
15
|
|
16
|
McDougal DB, Schulz DW, Passonneau JV, Clark JR, Reynolds MA, Lowry OH. Quantitative Studies of White Matter : I. Enzymes involved in glucose-6-phosphate metabolism. ACTA ACUST UNITED AC 2010; 44:487-98. [PMID: 19873533 PMCID: PMC2195104 DOI: 10.1085/jgp.44.3.487] [Citation(s) in RCA: 63] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Total lipid and six enzymes closely related to the metabolism of glucose-6-phosphate have been measured in ten tracts of the rabbit. Lipid content appears to be a valid indicator of the degree of myelination. Heavily myelinated tracts have much larger amounts of glucose-6-phosphate dehydrogenase than lightly myelinated ones but there is no corresponding difference in 6-phosphogluconate dehydrogenase. In fact the ratios between the two enzymes were found to vary over a ninefold range. Hexokinase is found in largest amounts in tracts with relatively little lipid, and this tends to be true for phosphofructokinase as well. The fibrillar layer of olfactory bulb is exceptional with regard to both enzymes, and to glucose-6-phosphate dehydrogenase. The enzymes are present in amounts which are more than adequate to support glucose metabolism at a rate commensurate with the known rates of O2 uptake by various tracts. The distribution of some of the enzymes is compatible with the notion that the nodes of Ranvier are regions of high metabolic activity. A simple algebraic relationship is found to hold fairly well for the distribution of four of the enzymes among the tracts.
Collapse
Affiliation(s)
- D B McDougal
- Department of Pharmacology and the Beaumont-May Institute of Neurology, Washington University School of Medicine, St. Louis
| | | | | | | | | | | |
Collapse
|
17
|
Ebersole JL, Steffen MJ, Reynolds MA, Branch-Mays GL, Dawson DR, Novak KF, Gunsolley JC, Mattison JA, Ingram DK, Novak MJ. Differential gender effects of a reduced-calorie diet on systemic inflammatory and immune parameters in nonhuman primates. J Periodontal Res 2008; 43:500-7. [PMID: 18565132 PMCID: PMC2574803 DOI: 10.1111/j.1600-0765.2008.01051.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
BACKGROUND AND OBJECTIVE Dietary manipulation, including caloric restriction, has been shown to impact host response capabilities significantly, particularly in association with aging. This investigation compared systemic inflammatory and immune-response molecules in rhesus monkeys (Macaca mulatta). MATERIAL AND METHODS Monkeys on continuous long-term calorie-restricted diets and a matched group of animals on a control ad libitum diet, were examined for systemic response profiles including the effects of both gender and aging. RESULTS The results demonstrated that haptoglobin and alpha1-antiglycoprotein levels were elevated in the serum of male monkeys. Serum IgG responses to Campylobacter rectus, Actinobacillus actinomycetemcomitans and Porphyromonas gingivalis were significantly elevated in female monkeys. While only the antibody to Fusobacterium nucleatum was significantly affected by the calorie-restricted diet in female monkeys, antibody levels to Prevotella intermedia, C. rectus and Treponema denticola demonstrated a similar trend. CONCLUSION In this investigation, only certain serum antibody levels were influenced by the age of male animals, which was seemingly related to increasing clinical disease in this gender. More generally, analytes were modulated by gender and/or diet in this oral model system of mucosal microbial challenge.
Collapse
Affiliation(s)
- J L Ebersole
- Center for Oral Health Research, College of Dentistry, University of Kentucky, Lexington, KY, USA.
| | | | | | | | | | | | | | | | | | | |
Collapse
|
18
|
Abstract
BACKGROUND Increasing use of IVF in the USA has been a major contributor to the rising national multiple birth rate. Many have advocated that reducing the number of embryos transferred is essential for addressing the IVF-associated multiple birth problem. METHODS A population-based sample of 506 072 IVF transfers performed in the USA in 1996-2002 was used to investigate trends in embryo transfer practices and to determine whether any changes in practice patterns have impacted the multiple gestation risk associated with IVF. RESULTS The proportion of procedures in which >or=3 embryos were transferred declined significantly for most patient groups between 1996 and 2002. However, declines for some groups were not sizeable (from 79 to 73% and from 76 to 71% for fresh, non-donor procedures among women aged 38-40 and 41-42 years respectively) and transferring >or=3 embryos remained the norm for all groups. As of 2002, single embryo transfer had not increased for most groups and remained uncommon. Some declines in overall multiple gestation rates were observed, although multiple gestation risk associated with 2 embryos transferred increased significantly for all groups. CONCLUSIONS Despite changes in embryo transfer practices, multiple gestation risk remains high, in part due to increased multiple gestation rates associated with the transfer of two embryos.
Collapse
Affiliation(s)
- M A Reynolds
- Division of Reproductive Health, National Center for Chronic Disease Prevention and Health Promotion, Centers for Disease Control and Prevention, Atlanta, Georgia 30329-1902, USA.
| | | |
Collapse
|
19
|
Abstract
BACKGROUND Multiple births are associated with serious adverse infant and maternal outcomes. The objective of this study was to assess the multiple-birth risk (MBR) associated with IVF and determine whether the risk is impacted by stage of embryo development at transfer. METHODS A population-based sample of 50 819 IVF transfers utilizing day 3 or day 5 embryos performed in the USA in 2001 on women aged 20-40 years was used to assess MBR and live-birth rate (LBR), stratified by patient age, supernumerary embryo availability, and number of embryos transferred. RESULTS Although significantly more day 5 than day 3 transfers used < or =2 embryos (69.2 versus 27.7%), the former were not associated with decreased MBR. MBR was high when >1 embryo was transferred, irrespective of embryo development stage. LBR were generally maximized with 2 embryos transferred, and for some (day 5 transfers, patients aged 35-37 years) with one embryo. Electing to transfer a single day 5 embryo appeared efficacious for some patients: women aged 20-37 years with supernumerary embryos cryopreserved had LBR of 31.6-39.5%. CONCLUSIONS MBR is high when > or =2 embryos are transferred. Single embryo transfer is the only way to prevent many multiple births and associated adverse health outcomes.
Collapse
Affiliation(s)
- D M Kissin
- Epidemic Intelligence Service, Epidemiology Program Office, Division of Reproductive Health, Centers for Disease Control and Prevention, Atlanta, GA 30341-3724, USA.
| | | | | |
Collapse
|
20
|
Hogrefe RI, Reynolds MA, Vaghefi MM, Young KM, Riley TA, Klem RE, Arnold LJ. An improved method for the synthesis and deprotection of methylphosphonate oligonucleotides. Methods Mol Biol 2003; 20:143-64. [PMID: 8242134 DOI: 10.1385/0-89603-281-7:143] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The methylphosphonate oligonucleotide synthesis methods described here give the desired products in good yield. Superior amounts of product are achieved by modifying both the DNA synthesis program and the reagent to compensate for the unstable methylphosphonite intermediate. Deprotection conditions have also been altered to maximize the recovery of oligonucleotide from DNA synthesis supports and to minimize the amount of base modification. Mass-spectrometry analysis of our oligonucleotides has verified their purity and confirmed the absence of modified bases. When compared to standard DNA synthesis methods, this procedure uses only about one-third the usual amount of monomer. Using these procedures, it should be possible to synthesize reliably methylphosphonate oligonucleotides at 1- and 15-mumol scales.
Collapse
|
21
|
Reynolds MA, Rauchfuss TB, Wilson SR. Ruthenium Derivatives of NiS 2N 2 Complexes as Analogues of Bioorganometallic Reaction Centers. Organometallics 2003. [DOI: 10.1021/om0340544] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
|
22
|
Nikitakis NG, Siavash H, Hebert C, Reynolds MA, Hamburger AW, Sauk JJ. 15-PGJ2, but not thiazolidinediones, inhibits cell growth, induces apoptosis, and causes downregulation of Stat3 in human oral SCCa cells. Br J Cancer 2002; 87:1396-403. [PMID: 12454768 PMCID: PMC2376283 DOI: 10.1038/sj.bjc.6600618] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2002] [Revised: 08/21/2002] [Accepted: 09/04/2002] [Indexed: 01/01/2023] Open
Abstract
Activation of peroxisome proliferator-activated receptor gamma (PPARgamma) has been linked to induction of differentiation, cell growth inhibition and apoptosis in several types of human cancer. However, the possible effects of PPARgamma agonists on human oral squamous cell carcinoma have not yet been reported. In this study, treatment with 15-deoxy-Delta(12,14)-PGJ(2) (15-PGJ(2)), a natural PPARgamma ligand, induced a significant reduction of oral squamous cell carcinoma cell growth, which was mainly attributed to upregulation of apoptosis. Interestingly, rosiglitazone and ciglitazone, two members of the thiazolidinedione family of PPARgamma activators, did not exert a growth inhibitory effect. Given the critical role that the oncogene signal transducer and activator of transcription 3 (Stat3) plays in head and neck carcinogenesis, its potential regulation by PPARgamma ligands was also examined. Treatment of oral squamous cell carcinoma cells with 15-PGJ(2) induced an initial reduction and eventual elimination of both phosphorylated and unphosphorylated Stat3 protein levels. In contrast, other PPARgamma did not induce similar effects. Our results provide the first evidence of significant antineoplastic effects of 15-PGJ(2) on human oral squamous cell carcinoma cells, which may be related to downmodulation of Stat3 and are at least partly mediated through PPARgamma-independent events.
Collapse
Affiliation(s)
- N G Nikitakis
- Department of Diagnostic Sciences and Pathology, University of Maryland, 666 W. Baltimore Street, Room 4-C-02, Baltimore, MD 21201, USA.
| | | | | | | | | | | |
Collapse
|
23
|
Coletta RD, Reynolds MA, Martelli-Junior H, Graner E, Almeida OP, Sauk JJ. Testosterone stimulates proliferation and inhibits interleukin-6 production of normal and hereditary gingival fibromatosis fibroblasts. Oral Microbiol Immunol 2002; 17:186-92. [PMID: 12030972 DOI: 10.1034/j.1399-302x.2002.170309.x] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Hereditary gingival fibromatosis (HGF) is a rare oral condition characterized by a slow and progressive enlargement of the gingiva, involving both the maxilla and mandible. In vitro, HGF fibroblasts demonstrate a proliferative index significantly higher than fibroblasts from normal gingiva (NG). The objective of this study was to determine the effect of dihydrotestosterone on the proliferation of gingival fibroblasts derived from patients with HGF (n = 4) and from four healthy individuals. Additionally, we analyzed the effect of dihydrotestosterone on interleukin-6 (IL-6) production and determined the expression levels of androgen receptors in NG and HGF fibroblasts. Gingival fibroblasts from NG and HGF were incubated with increasing concentrations of dihydrotestosterone with or without androgen blockers, and cultured for 24 h, and the proliferation index was determined by automated cell counter. IL-6 production, in this system, was quantified using a "capture" enzyme-linked immunosorbent assay (ELISA). Semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) was performed to measure the mRNA expression of androgen receptors. The results indicated that dihydrotestosterone simultaneously downregulates the production of IL-6 and upregulates the cell proliferation. Finasteride and cyprosterone acetate, two anti-androgens, partially reversed these effects. Androgen receptor mRNA expression was identified in both NG and HGF fibroblasts; however, the levels in NG were higher than those observed in HGF. These results show that testosterone coordinates the proliferation and production of IL-6 of normal and HGF fibroblasts.
Collapse
Affiliation(s)
- Ricardo D Coletta
- Department of Oral Pathology, University of Campinas Dental School, Caixa Postal 52, 13414-018 Piracicaba-SP, São Paulo, Brazil
| | | | | | | | | | | |
Collapse
|
24
|
Abstract
Multiple birth, which is associated with adverse fetal, infant, and maternal outcomes, is increasingly related to the use of in vitro fertilization (IVF). Among women undergoing IVF who use their own eggs, greater maternal age is associated with decreased risk of multiple birth; using donor eggs from younger women may negate this age effect. Data from 6,936 IVF procedures performed in the United States in 1996-1997 on women aged 35-54 years who used donor eggs were analyzed to assess the effect of maternal age, number of embryos transferred, and cryopreservation of extra, nontransferred embryos (an indicator of higher embryo quality) on risk of multiple birth. Greater maternal age did not decrease multiple-birth risk. Rates of multiple birth were related to number of embryos transferred and whether extra embryos had been cryopreserved, and they were high compared with those of IVF patients the same age who had used their own eggs. Among women who had extra embryos cryopreserved, transferring more than two embryos increased multiple-birth risk, with no corresponding increase in the chance for a livebirth. These results highlight the need to consider the age of the donor and embryo quality when making embryo transfer decisions involving use of donor eggs.
Collapse
Affiliation(s)
- M A Reynolds
- Epidemic Intelligence Service, Division of Applied Public Health Training, Epidemiology Program Office, Centers for Disease Control and Prevention, Atlanta, GA 30341-3717, USA.
| | | | | | | | | |
Collapse
|
25
|
Evertsz EM, Au-Young J, Ruvolo MV, Lim AC, Reynolds MA. Hybridization cross-reactivity within homologous gene families on glass cDNA microarrays. Biotechniques 2001; 31:1182, 1184, 1186 passim. [PMID: 11730025 DOI: 10.2144/01315dd03] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Glass cDNA microarrays can be used to profile the expression of thousands of gene targets in a single experiment. However, the potential for hybridization cross-reactivity needs to be considered when interpreting the results. Here, we describe hybridization experiments with a model array representing four distinct functional classes (families): chemokines, cytochrome P-450 isozymes, G proteins, and proteases. The cDNA clones selected for this array exhibited pairwise sequence identities ranging from 55% to 100%, as determined by a homology scoring algorithm (LALIGN). Targets for microarraying were amplified by PCR and spotted in 4-fold replication for signal averaging. One designated target from each family was further amplified by PCR to incorporate a T7 promoter sequence for the production of synthetic RNA transcripts. These transcripts were used to generate fluorescent hybridization probes by reverse transcription at varying input concentrations. As expected, hybridization signals were highest at the matching target elements. Targets containing less than 80% sequence identity relative to the hybridization probe sequences showed cross-reactivities ranging from 0.6% to 12%. Targets containing greater than 80% identity showed higher cross-reactivities (26%-57%). These cross-reactive signals were analyzed for statistical correlation with the length of sequence overlap, percent sequence identity, and homology score determined by LALIGN. Overall, percent sequence identity was the best predictor of hybridization cross-reactivity. These results provide useful guidelines for interpreting glass cDNA microarray data.
Collapse
|
26
|
Abstract
In the course of exploring the hybridization properties of glass DNA microarrays, multi-stranded DNA structures were observed that could not be accounted for by classical Watson-Crick base pairing. Non-denatured double-stranded DNA array elements were shown to hybridize to single-stranded (ss)DNA probes. Similarly, ssDNA array elements were shown to bind duplex DNA probes. This led to a series of experiments demonstrating the formation of multi-stranded DNA structures on the surface of microarrays. These structures were observed with a number of heterogeneous sequences, including both purine and pyrimidine bases, with shared sequence identity between the ssDNA and one of the duplex strands. Furthermore, we observed a strong binding preference near the ends of duplexes containing a 3'-homologous strand. We suggest that such binding interactions on cationic solid surfaces could serve as a model for a number of biological processes mediated through multi-stranded DNA.
Collapse
Affiliation(s)
- S J Shi
- Incyte Genomics, Microarray Division, 6519 Dumbarton Circle, Fremont, CA 94555, USA
| | | | | | | | | |
Collapse
|
27
|
Rauchfuss TB, Contakes SM, Hsu SC, Reynolds MA, Wilson SR. The influence of cyanide on the carbonylation of iron(II): synthesis of Fe-Sr-Cn-Co centers related to the hydrogenase active sites. J Am Chem Soc 2001; 123:6933-4. [PMID: 11448203 DOI: 10.1021/ja015948n] [Citation(s) in RCA: 77] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- T B Rauchfuss
- Department of Chemistry University of Illinois at Urbana-Champaign Urbana, Illinois 61801, USA
| | | | | | | | | |
Collapse
|
28
|
Abstract
BACKGROUND Guided bone regeneration (GBR) using a non-absorbable barrier has provided clinicians the ability to place implants in sites compromised by insufficient bone, including immediate extraction sites. Recent evidence suggests that successful GBR outcomes may be possible using bioabsorbable polymer barriers. METHODS This report presents a case series of 9 patients with 8 fenestration and 3 dehiscence defects on implants consecutively treated with GBR. A bioabsorbable polymer barrier of poly(DL-lactide) was used in conjunction with a composite graft of freeze-dried bone allograft (FDBA)/demineralized freeze-dried bone allograft (DFDBA) mixed in a ratio of 1:1. Second-stage surgeries were performed at 4 to 8.5 months (5. 7 months average) post-placement. Biopsy material from 2 sites was obtained while exposing the implant for healing abutment connection. RESULTS Ten of the 11 defects (90.9%) achieved complete coverage of the osseous defects. Histologic evaluations revealed the formation of viable bone, frequently in close amalgamation with residual graft particles. CONCLUSION These case reports suggest that a poly(DL-lactide) polymer can be used as a physical barrier with a composite bone replacement graft to achieve successful GBR results of dehiscence/fenestration defects when placing implants.
Collapse
Affiliation(s)
- P S Rosen
- Department of Periodontics, Baltimore College of Dental Surgery, University of Maryland, USA
| | | |
Collapse
|
29
|
Kassolis JD, Rosen PS, Reynolds MA. Alveolar ridge and sinus augmentation utilizing platelet-rich plasma in combination with freeze-dried bone allograft: case series. J Periodontol 2000; 71:1654-61. [PMID: 11063400 DOI: 10.1902/jop.2000.71.10.1654] [Citation(s) in RCA: 238] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
BACKGROUND Alveolar bone regeneration is frequently necessary prior to placement of implants. Efforts to improve wound healing have focused on factors that may enhance bone formation following guided bone regeneration (GBR) techniques alone or in combination with bone replacement graft materials. Recent reports suggest that platelet-rich plasma (PRP), presumably high in levels of peptide growth factors, may enhance the formation of new bone when used in combination with autogenous graft material. METHODS In this report, the clinical and radiographic results are presented on 15 consecutively treated patients using autologous PRP in combination with freeze-dried bone allograft (FDBA) for sinus elevation and/or ridge augmentation. FDBA and PRP (0.5 g/2cc PRP) were mixed and placed as a composite graft material. A gel formed by mixing autologous thrombin-rich plasma with PRP (1:4 ratio) was used to cover the graft material. Core biopsies of grafted areas were obtained in several patients as part of implant site preparation and were evaluated histologically to determine site maturation. RESULTS Of 36 implant fixtures, 32 (89%) were considered clinically successful demonstrating complete bone coverage of the implant, no mobility, and a normal radiographic appearance at the time of re-entry and 12 months post-implant exposure. Four implants were removed due to mobility at the time of surgical exposure. Histologic evaluation of biopsy specimens revealed numerous areas of osteoid and bone formation around FDBA particles, with no evidence of inflammatory cell infiltrate. CONCLUSIONS These clinical and histological findings suggest that ridge augmentation and sinus grafting with FDBA in combination with PRP provide a viable therapeutic alternative for implant placements. Future studies are necessary to determine whether PRP enhances new bone formation or maturation with bone replacement allografts.
Collapse
Affiliation(s)
- J D Kassolis
- Department of Periodontics, University of Maryland, Dental School, Baltimore, USA
| | | | | |
Collapse
|
30
|
Coletta RD, Almeida OP, Ferreira LR, Reynolds MA, Sauk JJ. Increase in expression of Hsp47 and collagen in hereditary gingival fibromatosis is modulated by stress and terminal procollagen N-propeptides. Connect Tissue Res 2000; 40:237-49. [PMID: 10757112 DOI: 10.3109/03008209909000702] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
HGF is a rare oral condition characterized by a slow, progressive enlargement of the gingiva, involving both the maxilla and mandible. HGF provides a model for the study of regulatory features of conditions characterized by connective tissue hyperplasia. In this study, the culture characteristics of gingival fibroblasts derived from patients of the same family with HGF (n = 4) were similar with regard to cell cycle analysis. Flow cytometric DNA content analysis revealed uniform DNA diploidy for fibroblasts cultured from NG and HGF. NG cells showed a low S-phase fraction (19.8%) and G2/M fraction (5.8%) and a relatively high G1 phase fraction (74%). In contrast, HGF cells from all members of the tested kindred, exhibited diploid cells with a higher S-phase (40.9%) and G2/M (10.1%) fraction and a relatively low G1 phase fraction (40.9%). Furthermore, we demonstrated that the expression and production of Hsp47 parallels the increased levels of collagen secretion observed in HGF. In addition, we show that Hsp47 and collagen are coordinately regulated following stress via a feedback mechanism mediated by N-terminal procollagen propeptides. Utilizing confocal microscopy and antibodies directed against GST-fusion proteins encompassing the pro alpha1(I) N-propeptide globular domain (NP1) (residues 23-108), it was apparent that this regulatory mechanism does not involve significant interaction with Hsp47's chaperoning of procollagen.
Collapse
Affiliation(s)
- R D Coletta
- Department of Oral Pathology, Dental School, University of Campinas, Piracicaba, São Paulo, Brazil
| | | | | | | | | |
Collapse
|
31
|
Pavco PA, Bouhana KS, Gallegos AM, Agrawal A, Blanchard KS, Grimm SL, Jensen KL, Andrews LE, Wincott FE, Pitot PA, Tressler RJ, Cushman C, Reynolds MA, Parry TJ. Antitumor and antimetastatic activity of ribozymes targeting the messenger RNA of vascular endothelial growth factor receptors. Clin Cancer Res 2000; 6:2094-103. [PMID: 10815937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Chemically stabilized hammerhead ribozymes are nuclease-resistant, RNA-based oligonucleotides that selectively bind and cleave specific target RNAs. Due to their potential for specifically inhibiting gene expression, ribozymes are being investigated for therapeutic applications as well as for the elucidation of gene function. In particular, we have investigated ribozymes that target the mRNA of the vascular endothelial growth factor (VEGF) receptors because VEGF signaling is an important mediator of tumor angiogenesis and metastasis. Here we report pharmacodynamic studies testing anti-Flt-1 (VEGFR-1) and anti-KDR (VEGFR-2) ribozymes in animal models of solid tumor growth and metastasis. Ribozymes targeting either Flt-1 or KDR significantly inhibited primary tumor growth in a highly metastatic variant of Lewis lung carcinoma. However, only treatment with the anti-Flt-1 ribozyme resulted in a statistically significant and dose-dependent inhibition of lung metastasis in this model. The anti-Flt-1 ribozyme was then tested in a xenograft model of human metastatic colorectal cancer in which significant inhibition of liver metastasis was observed. Taken together, these data represent the first demonstration that synthetic ribozymes targeting VEGF receptor mRNA reduced the growth and metastasis of solid tumors in vivo.
Collapse
MESH Headings
- Animals
- Antineoplastic Agents/therapeutic use
- Carcinoma, Lewis Lung/drug therapy
- Carcinoma, Lewis Lung/pathology
- Colorectal Neoplasms/drug therapy
- Colorectal Neoplasms/pathology
- Disease Models, Animal
- Dose-Response Relationship, Drug
- Female
- Humans
- Liver Neoplasms/prevention & control
- Liver Neoplasms/secondary
- Male
- Mice
- Mice, Inbred C57BL
- Mice, Nude
- Neoplasm Metastasis/prevention & control
- Neoplasm Transplantation
- RNA, Catalytic/genetics
- RNA, Catalytic/therapeutic use
- RNA, Messenger/antagonists & inhibitors
- RNA, Messenger/genetics
- Receptor Protein-Tyrosine Kinases/antagonists & inhibitors
- Receptor Protein-Tyrosine Kinases/genetics
- Receptors, Growth Factor/antagonists & inhibitors
- Receptors, Growth Factor/genetics
- Receptors, Vascular Endothelial Growth Factor
- Transplantation, Heterologous
- Tumor Cells, Cultured
Collapse
Affiliation(s)
- P A Pavco
- Ribozyme Pharmaceuticals Inc, Boulder, Colorado 80301, USA.
| | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
32
|
Abstract
There is substantial clinical and histological evidence that support the concept that extraoral and intraoral autogenous bone grafts and demineralized freeze-dried bone allografts are effective regenerative materials in the treatment of intrabony defects. Moreover, long-term evaluations currently available suggest that the regenerative gains achieved remain clinically stable. Synthetic grafts may result in improved probing depths and clinical attachment levels but have yet to demonstrate the ability to initiate or enhance the formation of a new attachment apparatus.
Collapse
Affiliation(s)
- P S Rosen
- Department of Periodontics, Baltimore College of Dental Surgery, University of Maryland Dental School, Baltimore, Maryland, USA
| | | | | |
Collapse
|
33
|
Coletta RD, Almeida OP, Reynolds MA, Sauk JJ. Alteration in expression of MMP-1 and MMP-2 but not TIMP-1 and TIMP-2 in hereditary gingival fibromatosis is mediated by TGF-beta 1 autocrine stimulation. J Periodontal Res 1999; 34:457-63. [PMID: 10697802 DOI: 10.1111/j.1600-0765.1999.tb02281.x] [Citation(s) in RCA: 56] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Hereditary gingival fibromatosis (HGF) is characterized by an excess accumulation of extracellular matrix (ECM) resulting in a generalized and fibrotic enlargement of the gingiva. To investigate some of the regulatory features of this condition, gingival fibroblasts from normal gingiva (NG) and HGF were examined for the expression and production of matrix metalloproteinases (MMPs) and their inhibitors, tissue matrix metalloproteinases inhibitor (TIMPs). Our results, obtained from 2 different assays, semi-quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) and enzymography, clearly demonstrated that the expression and production of MMP-1 and MMP-2 was significantly lower in fibroblasts from HGF than from NG. Interestingly, TIMP-1 and TIMP-2 expression from NG cells was shown to be slightly higher to those from HGF. Addition of antibodies against transforming growth factor-beta 1 (TGF-beta 1), which is produced in greater amounts by HGF fibroblasts, resulted in a slight increase in MMP-1 and a decrease in MMP-2 expression, whereas TIMP-1 and TIMP-2 expressions were unaffected. These patterns of expression and production suggest that enhanced TGF-beta 1 production reduce the proteolytic activities of HGF fibroblasts, which favor the accumulation of ECM.
Collapse
Affiliation(s)
- R D Coletta
- Department of Oral Pathology, Dental School, University of Campinas Piracicaba, São Paulo, Brazil.
| | | | | | | |
Collapse
|
34
|
Stickle DF, Reynolds MA, Morris MD, Quon MJ. Dynamic changes in plasma proinsulin/insulin ratio during insulin secretion influence correlation between radioimmunoassay (RIA) and IMX measurements of insulin. Clin Chim Acta 1999; 284:1-13. [PMID: 10437638 DOI: 10.1016/s0009-8981(99)00072-8] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
Because proinsulin and insulin have different circulatory half-lives, the ratio of proinsulin to insulin in plasma depends on the dynamics of insulin secretion. This variation can potentially influence comparison of IMX assays and radioimmunoassays (RIAs) for [insulin], given that the antibody used in the IMX assay has negligible cross-reactivity with proinsulin compared to the 40% cross-reactivity with proinsulin of the antibody used in the RIA. Simulation of a simple mass balance model for insulin and proinsulin concentrations during an oral glucose tolerance test predicts that the ratio (R) of RIA to IMX insulin measurements of [insulin] should transiently decrease, pass through a minimum, increase past the initial value, pass through a maximum and eventually return to the initial value. Using time course specimens from patients, this pattern of variation in R was observed in the majority (12/16) of cases studied. The variation in R for time course specimens (CV = 26%) was significantly greater than for other specimens (fasting, random or undesignated; P < 0.05). Thus, when comparing IMX and RIA measurements of [insulin], variation in R for samples from differing states of dynamic insulin secretion contains a component that is attributable to dynamic changes in the ratio of [proinsulin]/[insulin] in plasma.
Collapse
Affiliation(s)
- D F Stickle
- Department of Pathology, Brooke Army Medical Center, Fort Sam Houston, TX, USA.
| | | | | | | |
Collapse
|
35
|
Sandberg JA, Bouhana KS, Gallegos AM, Agrawal AB, Grimm SL, Wincott FE, Reynolds MA, Pavco PA, Parry TJ. Pharmacokinetics of an antiangiogenic ribozyme (ANGIOZYME) in the mouse. Antisense Nucleic Acid Drug Dev 1999; 9:271-7. [PMID: 10435752 DOI: 10.1089/oli.1.1999.9.271] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Vascular endothelial growth factor (VEGF) is a growth factor that contributes to the angiogenesis of developing tumors. To interfere with the action of VEGF, a nuclease-stabilized ribozyme, ANGIOZYME, has been developed against VEGF receptor subtype Flt-1 mRNA. To determine which routes of administration would be useful for systemic delivery of this ribozyme, a dose of 30 mg/kg [32P]ANGIOZYME was administered as an i.v., i.p., or s.c. bolus. Concentrations of ANGIOZYME in plasma, femur, kidney, liver, and lung were examined. ANGIOZYME was well absorbed after i.p. (90%) or s.c. administration (77%), with peak plasma concentrations occurring 30 minutes after dosing. Total body clearance after a single dose of 30 mg/kg ANGIOZYME was 20 ml/min/kg, and the elimination half-life was 33 minutes. The apparent volume of distribution at steady-state ranged from 0.5 to 1.3 L/kg. ANGIOZYME was detected in the four tissues examined through the 3 hour sampling period after i.v. or i.p. administration. After s.c. administration, ANGIOZYME was detected in femur, kidney, and lung but not in the liver. The highest concentrations of ANGIOZYME were found in kidney and femur with all three routes. Because of the rapid and extensive absorption after extravascular injections, either i.p. or s.c. administration could be considered for use in pharmacodynamic studies examining the effects of ANGIOZYME or other ribozymes with similar chemical modifications.
Collapse
Affiliation(s)
- J A Sandberg
- Ribozyme Pharmaceuticals, Inc., Boulder, CO 80301, USA
| | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Rosen PS, Reynolds MA. Polymer-assisted regenerative therapy: case reports of 22 consecutively treated periodontal defects with a novel combined surgical approach. J Periodontol 1999; 70:554-61. [PMID: 10368061 DOI: 10.1902/jop.1999.70.5.554] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
This report describes the clinical application of an in situ formed barrier of poly(DL-lactide) used in combination with a composite graft of demineralized freeze-dried bone allograft (DFDBA) mixed with calcium sulfate and tetracycline in a ratio of 7:2:1 and citric acid root conditioning for the treatment of intrabony and furcation defects. The clinical outcome was assessed by changes in clinical attachment level (CAL) and probing depth (PD) in 18 consecutively treated patients with 17 intrabony and 5 furcation lesions. After patients demonstrated acceptable oral hygiene, the lesions were surgically treated with combination therapy using an in situ formed barrier over a DFDBA composite graft. Patients followed a stringent postoperative protocol and were evaluated at 6 months postsurgery. CAL improved for all sites from a presurgical average of 8.8+/-2.3 mm to 4.4+/-1.6 mm at 6 months postsurgery (4.4+/-1.5 mm gain), while PD was reduced from an average of 8.3+/-2.1 mm presurgery to 3.3+/-1.1 mm at 6 months postsurgery (5.0+/-1.8 mm reduction). Five furcations were treated, of which 4 were Class II and 1 was Class III. Of these furcation lesions, 3 had complete clinical closure, while 1 improved by 1 grade. The Class III furcation remained the same. Results suggest that DFDBA composite graft covered by an in situ formed barrier on root surfaces treated with citric acid can enhance the prognoses of teeth with periodontal lesions as measured by CAL gains and PD reductions. Further studies are warranted to compare this treatment to other more traditional forms of regenerative therapy to determine its comparative efficacy.
Collapse
Affiliation(s)
- P S Rosen
- Department of Periodontology, Baltimore College of Dental Surgery, University of Maryland, USA
| | | |
Collapse
|
37
|
Meier RR, Nicholas AC, Picone JM, Melendez-Alvira DJ, Ganguli GI, Reynolds MA, Roelof EC. Inversion of plasmaspheric EUV remote sensing data from the STP 72-1 satellite. ACTA ACUST UNITED AC 1998. [DOI: 10.1029/98ja01175] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
38
|
Rosen PS, Reynolds MA, Bowers GM. A technique report on the in situ application of Atrisorb as a barrier for combination therapy. INT J PERIODONT REST 1998; 18:249-55. [PMID: 9728107] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
This article describes a novel technique in which Atrisorb (Atrix Laboratories) is applied in situ as a barrier over a demineralized freeze-dried bone allograft on roots treated with citric acid. Follow-up reentry at 4.5 months demonstrated the effectiveness of this procedure. A rationale for in situ barrier application is presented.
Collapse
Affiliation(s)
- P S Rosen
- Baltimore College of Dental Surgery, University of Maryland, USA
| | | | | |
Collapse
|
39
|
Fell PL, Hudson AJ, Reynolds MA, Usman N, Akhtar S. Cellular uptake properties of a 2'-amino/2'-O-methyl-modified chimeric hammerhead ribozyme targeted to the epidermal growth factor receptor mRNA. Antisense Nucleic Acid Drug Dev 1997; 7:319-26. [PMID: 9303183 DOI: 10.1089/oli.1.1997.7.319] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Catalytic RNA or ribozymes have important potential applications as molecular biological tools in the study of gene expression and as therapeutic inhibitors of disease-causing genes. Very little is known, however, about the cellular uptake mechanisms of exogenously delivered synthetic ribozymes. In this study, we have characterized the uptake properties of a synthetic, 2'-O-methyl-modified ribozyme containing U4/U7 amino groups within the catalytic core of the hammerhead motif. The cellular uptake of the internally [32P]-radiolabeled hammerhead ribozyme in U87-MG glioma cells was temperature, energy, and pH dependent and involved an active process that could be competed with cold ribozyme of the same chemistry and sequence, an all 2'-O-methyl-modified ribozyme of the same sequence, antisense PS-ODNs, and a variety of other polyanions (salmon sperm DNA, spermidine, dextran sulfate, and heparin). Subcellular distribution studies of fluorescently labeled ribozymes confirmed an extranuclear, punctate localization similar to that observed for an endosomal marker, dextran. Our study highlights that hammerhead ribozymes, despite exhibiting a defined secondary structure, enter cells by an endocytic mechanism that appears to be similar to that reported for a variety of antisense ODNs. These observations should facilitate the development of more efficient delivery systems.
Collapse
Affiliation(s)
- P L Fell
- Pharmaceutical Sciences Institute, Aston University, Birmingham, U.K
| | | | | | | | | |
Collapse
|
40
|
George KS, Reynolds MA, Falkler WA. Arbitrarily primed polymerase chain reaction fingerprinting and clonal analysis of oral Fusobacterium nucleatum isolates. Oral Microbiol Immunol 1997; 12:219-26. [PMID: 9467390 DOI: 10.1111/j.1399-302x.1997.tb00382.x] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Abstract
F. nucleatum is the most commonly isolated microorganism from subgingival plaque, but the role of this microorganism in periodontal diseases remains undefined. Arbitrarily primed polymerase chain reaction (AP-PCR) was evaluated as a method for fingerprinting F. nucleatum isolates and for use in clonal analysis. Pulsed field gel electrophoresis was used to further differentiate F. nucleatum isolates, with identical AP-PCR patterns. Extremely heterogeneous AP-PCR fingerprints were observed among the 98 F. nucleatum isolates, with 36 different genotypes observed with primer C1 and 30 different genotype detected with primer C2. Combining the results of the AP-PCR genotype analysis from C1 and C2 primer amplifications revealed that up to 7 different genotypes could be distinguished from isolates from the same oral cavity and that up to 4 different genotypes were observed within a single site. An intense amplicon at approximately 450 bp generated in AP-PCR amplification with primer C2 was associated with F. nucleatum subsp. nucleatum (ATCC 25586) and with 15 F. nucleatum isolates from diseased sites and 2 isolates from healthy sites. Pulsed field gel electrophoresis confirmed the AP-PCR genotypes and demonstrated increased discriminatory power over AP-PCR. The results indicated that AP-PCR and pulsed field gel electrophoresis provide a simple and sensitive means for differentiating oral F. nucleatum isolates and further demonstrate the heterogeneity of this species. These techniques may serve as useful tools in the clonal and epidemiological analysis of F. nucleatum isolates, which may help define the role of these microorganisms in periodontal diseases.
Collapse
Affiliation(s)
- K S George
- Department of Oral and Craniofacial Biological Sciences, University of Maryland Dental School, Baltimore 21201, USA
| | | | | |
Collapse
|
41
|
Mujeeb A, Reynolds MA, James TL. High-resolution NMR of an antisense DNA x RNA hybrid containing alternating chirally pure Rp methylphosphonates in the DNA backbone. Biochemistry 1997; 36:2371-9. [PMID: 9054542 DOI: 10.1021/bi963008n] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
A high-resolution proton NMR study has been performed on a hybrid duplex formed by a methylphosphonate (MP) oligodeoxyribonucleotide (MPO) and its target oligoribonucleotide, d(T(MP)CC(MP)-TT(MP)AG(MP)CT(MP)CC(MP)TG) x r(CAGGAGCUAAGGA), where MP corresponds to positions of methylphosphonate linkages in the pure R(p) stereoconfiguration. MP-containing analogs of DNA are reported to be effective antisense agents capable of specifically inhibiting protein synthesis with the R(p) chiral MPOs exhibiting greater affinity for the target mRNA than their S(p) counterparts. Nearly complete proton resonance assignments of the hybrid duplex have been made using two-dimensional nuclear Overhauser effect (2D NOE) spectra, at three different mixing times, and double quantum-filtered COSY (2QF-COSY) spectra. The 2QF-COSY cross-peak patterns which are resolved have been analyzed qualitatively to suggest sugar conformations. Distance restraints have been obtained from the 2D NOE spectra of the duplex in D(2)O. These interproton distance restraints were determined using a complete relaxation matrix method to improve accuracy. Specifically, a new approach termed RANDMARDI has been utilized to calculate these distance restraints, accounting for spectral noise and errors in 2D NOE peak volume integration. The calculated interproton distances and sugar puckers have been analyzed to assess the solution conformation of the hybrid. The hybrid duplex appears to have an overall solution structure which is distinct from standard B- and A-forms, but the RNA strand exhibits features of the A-form. The absence of H1'-H2' cross-peaks in the 2QF-COSY spectrum indicates a C3'-endo type of conformation for ribose sugars in the RNA strand. The deoxyriboses in the antisense DNA strand exhibit a mixed behavior with almost equal scalar coupling constant values for H1'-H2' and H1'-H2" and a strong H3'-H4' 2QF-COSY peak pattern. Variations in calculated values of interproton distances and sixth-root R factor analysis of experimental intensities indicate that the hybrid duplex may have a DNA strand with significant conformational plasticity.
Collapse
Affiliation(s)
- A Mujeeb
- Department of Pharmaceutical Chemistry, University of California, San Francisco 94143-0446, USA
| | | | | |
Collapse
|
42
|
Reynolds MA, Hogrefe RI, Jaeger JA, Schwartz DA, Riley TA, Marvin WB, Daily WJ, Vaghefi MM, Beck TA, Knowles SK, Klem RE, Arnold LJ. Synthesis and thermodynamics of oligonucleotides containing chirally pure R(P) methylphosphonate linkages. Nucleic Acids Res 1996; 24:4584-91. [PMID: 8948653 PMCID: PMC146287 DOI: 10.1093/nar/24.22.4584] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023] Open
Abstract
Methylphosphonate (MP) oligodeoxynucleotides (MPOs) are metabolically stable analogs of conventional DNA containing a methyl group in place of one of the non-bonding phosphoryl oxygens. All 16 possible chiral R(P) MP dinucleotides were synthesized and derivatized for automated oligonucleotide synthesis. These dimer synthons can be used to prepare (i) all-MP linked oligonucleotides having defined R(P) chirality at every other position (R(P) chirally enriched MPOs) or (ii) alternating R(P) MP/phosphodiester backbone oligonucleotides, depending on the composition of the 3'-coupling group. Chirally pure dimer synthons were also prepared with 2'-O-methyl sugar modifications. Oligonucleotides prepared with these R(P) chiral methylphosphonate linkage synthons bind RNA with significantly higher affinity than racemic MPOs.
Collapse
|
43
|
Abstract
This retrospective study compares the short-term (1 year) and long-term (2 to 5 year) clinical results of regenerative therapy in clinical private practice using a bone allograft for the treatment of intrabony defects in smokers and non-smokers. A total of 110 intrabony lesions were treated with demineralized freeze-dried bone allograft (DFDBA) following thorough defect debridement and root preparation in 53 patients (15 cigarette smokers and 38 non-smokers). Assessments of clinical attachment level (CAL) and probing depth (PD) were recorded at pre-treatment, 1 year post-treatment, and 2 to 5 years post-treatment. At 1 year post-treatment, significant gains in mean CAL were maintained for both smokers (2.7 mm) and non-smokers (3.4 mm). Similarly, significant reductions in mean PD were observed for smokers (3.0 mm) and non-smokers (3.8 mm) at the 1-year follow-up. However, when comparing relative improvements in clinical measures, smokers were found to exhibit significantly poorer treatment results (i.e., sites exhibited less CAL gain) at 1 year and 2 to 5 years follow-up. Relative to pre-treatment scores, differences in improvements observed for CAL at the 1-year evaluation (29.2% for smokers and 42.5% for non-smokers) were sustained in the subgroup of patients at 2 to 5 years follow-up (31.3% for smokers and 41.8% for non-smokers). Similar but non-significant trends were observed for relative reductions in probing depth for smokers and non-smokers at 1 year (41.9% for smokers and 49.3% for non-smokers) and 2 to 5 years follow-up (43.9% for smokers and 48.3% for non-smokers) for the subgroup of patients followed beyond 1 year. These results suggest that smoking adversely affects treatment outcome, as measured by gains in clinical attachment levels of intrabony defects treated by regenerative therapy using DFDBA.
Collapse
Affiliation(s)
- P S Rosen
- Department of Periodontics, University of Maryland at Baltimore, USA
| | | | | |
Collapse
|
44
|
Trapane TL, Hogrefe RI, Reynolds MA, Kan LS, Ts'o PO. Interstrand complex formation of purine oligonucleotides and their nonionic analogs: the model system of d(AG)8 and its complement, d(CT)8. Biochemistry 1996; 35:5495-508. [PMID: 8611541 DOI: 10.1021/bi960070b] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
We have investigated the role of purines in interstrand complex formation with regard to substitution of the negatively-charged, phosphodiester backbone by a nonionic, internucleoside linkage. Using the purine oligomer, d(AG)8, its methylphosphonate analog, d(AG)8, and the complementary pyrimidine oligomer, d(CT)8, as a model system, the stoichiometry, conformation, and stability of complexes formed at pH 8 were studied by spectroscopic and electrophoretic methods. When there is only one oligomer species in solution, d(AG)8 behaves as a single-stranded molecule. In contrast, the d(AG)8 oligomer readily forms an intermolecular self-complex, particularly in the presence of magnesium ion. Using either purine oligomer, duplexes can form with the d(CT)8 strand which differ in terms of their conformation and in the dependence of their thermal stability on sodium and magnesium ions. All studies show that a stable triplex forms with a 1:2 d(CT)8:d(AG)8 stoichiometry which does not require high concentrations of sodium or magnesium ions. Triplex formation between the d(CT)8 strand and two d(AG)8 strands was not observed. Native gel electrophoresis suggests that a 1:1:1 d(CT)8:d(AG)8:d(AG)8 complex may be formed. In regard to triplex formation, the advantage of the methylphosphonate backbone on the purine strand is clearly demonstrated.
Collapse
Affiliation(s)
- T L Trapane
- Department of Biochemistry, School of Hygiene and Public Health, Johns Hopkins University, Baltimore, Maryland 21205, USA
| | | | | | | | | |
Collapse
|
45
|
Reynolds MA, Beck TA, Say PB, Schwartz DA, Dwyer BP, Daily WJ, Vaghefi MM, Metzler MD, Klem RE, Arnold LJ. Antisense oligonucleotide containing an internal, non-nucleotide-based linker promote site-specific cleavage of RNA. Nucleic Acids Res 1996; 24:760-65. [PMID: 8604321 PMCID: PMC145679 DOI: 10.1093/nar/24.4.760] [Citation(s) in RCA: 46] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
We have designed and synthesized a series of novel antisense methylphosphonate oligonucleotide (MPO) cleaving agents that promote site-specific cleavage on a complementary RNA target. These MPOs contain a non- nucleotide-based linking moiety near the middle of the sequence in place of one of the nucleotide bases. The region surrounding the unpaired base on the RNA strand (i.e. the one directly opposite the non-nucleotide-linker) is sensitive to hydrolytic cleavage catalyzed by ethylenediamine hydrochloride. Furthermore, the regions of the RNA comprising hydrogen bonded domains are resistant to cleavage compared with single-stranded RNA alone. Several catalytic moieties capable of supporting acid/base hydrolysis were coupled to the non-nucleotide-based linker via simple aqueous coupling chemistries. When tethered to the MPO in this manner these moieties are shown to catalyze site-specific cleavage on the RNA target without any additional catalyst.
Collapse
|
46
|
Abstract
Demineralized freeze-dried bone (DFDBA) is the most widely used allograft in periodontics. Little information exists, however, on the fate of DFDBA matrix or on the effects of residual particles within grafted defects. The purpose of this study was to histologically examine the fate of DFDBA used for regeneration in intrabony defects. A secondary objective was to compare the amount of new attachment apparatus formation, including component tissues, in relation to the presence or absence of residual graft material. Histologic data were obtained from earlier studies in which intrabony defects grafted with DFDBA were removed at 6 months en bloc and submitted for histologic examination. Histologic sections (1,120) from 12 patients with 32 grafted defects revealed that 72% of the grafted defects exhibited residual DFDBA particles. When present, DFDBA appeared amalgamated within the new viable bone. Data from 5 patients with 14 grafted sites permitted a within-subject comparison of the amount of regeneration in relation to the presence or absence of residual graft material. Defects harboring residual graft particles exhibited significantly greater amounts of new attachment apparatus formation (1.72 mm vs. 0.20 mm), including new bone (2.33 mm vs. 0.23 mm), cementum (1.74 mm vs. 0.23 mm), and associated periodontal ligament than sites without evidence of graft matrix (P < or = 0.05). No apparent differences were seen in the nature of the new attachment apparatus or component tissues, other than in amount of formation. Inflammation and graft containment appear to be important factors influencing the fate of DFDBA and the regenerative response.
Collapse
Affiliation(s)
- M A Reynolds
- Department of Periodontics, University of Maryland, Dental School, Baltimore, USA
| | | |
Collapse
|
47
|
Spain DA, DeWeese RC, Reynolds MA, Richardson JD. Transpyloric passage of feeding tubes in patients with head injuries does not decrease complications. J Trauma 1995; 39:1100-2. [PMID: 7500401 DOI: 10.1097/00005373-199512000-00015] [Citation(s) in RCA: 50] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
Early enteral nutrition is reported to improve outcome of patients with severe closed head injuries (CHI). The efficacy and safety of nasoenteric tube (NET) feeds, however, has been questioned; the risk of aspiration is the major concern. Our purpose was to determine the rate of transpyloric migration, the efficacy of adjunctive measures to promote passage, and the effect on pulmonary complications. Seventy-four consecutive patients with moderate to severe CHI received enteral nutrition. Glasgow Coma Scale (GSC) score was 5.2 on admission and 6.9 at 48 hours. NETs were placed an average of 5.6 days after admission; an average of three abdominal films per patient were used to assess tube position. No patients had endoscopic NET placement during this period. Ten patients required fluoroscopic placement after failure to pass spontaneously by 5 days. Overall, transpyloric passage was achieved in 32 patients (43%), whereas 42 (57%) remained intragastric. There were no differences between the postpyloric and intragastric groups in days to full feeding (5 vs. 7 days), ventilator days (11.9 vs. 12.5), intensive care unit length of stay (15.5 vs. 15.1), or incidence of pneumonia (81 vs. 69%) or aspiration (6 vs 7%). Sixty-two patients (83%) were transferred to extended care facilities and 50 (68%) were still receiving NET feedings. Spontaneous transpyloric passage of NET occurred in less than one-half of patients with severe CHI. The routine use of adjunctive measures to promote transpyloric passage was not particularly successful, had no obvious benefit, and therefore may not be necessary.
Collapse
Affiliation(s)
- D A Spain
- Department of Surgery, University of Louisville School of Medicine, Kentucky 40292, USA
| | | | | | | |
Collapse
|
48
|
Reynolds MA, Richardson JD, Spain DA, Seligson D, Wilson MA, Miller FB. Is the timing of fracture fixation important for the patient with multiple trauma? Ann Surg 1995; 222:470-8; discussion 478-81. [PMID: 7574927 PMCID: PMC1234876 DOI: 10.1097/00000658-199522240-00005] [Citation(s) in RCA: 96] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVE The effect of timing of femur fracture fixation for patients with multiple trauma was studied to determine the effect of operative timing on eventual outcome. METHODS The relationship between timing of intramedullary rod (IMR) placement, degree of injury, and pulmonary complications was studied in 424 consecutive patients. The authors focused on 105 patients undergoing IMR placement with an Injury Severity score (ISS) of greater than or equal to 18. The effects of timing of IMR placement on various pulmonary complications, organ failure, intensive care unit (ICU) admission, and ventilatory assistance were studied for various time intervals. RESULTS Of the 424 patients, pulmonary complications increased slightly in the more seriously injured group (ISS > 18) but were not influenced by the timing of IMR placement. Of the 105 patients undergoing IMR placement with an ISS > or = 18, only 2 patients died. Both patients had an IMR placed in less than 24 hours and died later of head injury and delayed hemorrhage. The incidence of organ failure, number of ventilator days, and length of ICU stay did not differ between the groups based on timing of fracture fixation. The incidence of severe head injuries was higher in the group undergoing delayed IMR placement (> 48 hours). CONCLUSIONS Modest delays in IMR placement did not adversely affect patient outcome. Pulmonary complications were related to the severity of injury rather than to timing of fracture fixation. In a well-integrated trauma system, clinical judgment regarding the timing of IMR placement was the most important determinant of outcome. Delays that were made to stabilize the patient, treat associated injuries, and plan orthopedic reconstruction did not adversely affect patient outcome.
Collapse
Affiliation(s)
- M A Reynolds
- Department of Surgery, University of Louisville School of Medicine, Kentucky, USA
| | | | | | | | | | | |
Collapse
|
49
|
Reynolds MA, Siow Y, Collet D, Klar E, Richardson JD, Vitale GC. The role of bile acid secretion in the hepatic response to operation and infection. Am Surg 1995; 61:469-74. [PMID: 7762892] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Hepatic function is altered in many surgery-related diseases. Bile acid secretion is the major determinant of bile formation and an important indicator of overall hepatic function. To investigate the cause of intrahepatic cholestasis, which is frequently associated with sepsis, we studied the effects of cecal ligation and puncture (CLP) and surgical stress on bile acid secretion and composition. CLP or a sham operation was performed on 20 male Sprague-Dawley rats. Bile was collected from each rat by cannulation of the common bile duct for 10-minute intervals, at 5 and 20 hours after the initial procedure. Bile acid analysis was then performed by high performance liquid chromatography (HPLC). In CLP rats, there was a significant (P < 0.05) cholestatic effect. Bile flow was reduced to 70 +/- 13 per cent at 5 hours, and to 55 +/- 16 per cent at 20 hours (per cent of the sham mean value). In the sham-operated rats, there was a significant choleresis at 20 hours. Bile flow was increased to 146 +/- 13 per cent; bile acid secretion to 245 +/- 24 per cent; and total bile acid concentration to 175 +/- 19 per cent of the sham 5-hour value (P < 0.05). This increased secretion was significantly greater in the metabolites of chenodeoxycholate. However, these surgical stress-associated changes in bile acid secretion and composition did not occur in CLP rats. These findings are consistent with surgical stress-induced induction of 7 alpha-hydroxylase, which was not found in the septic animals. These observations may provide useful insights into the early stages of the pathogenesis of sepsis-related hepatic dysfunction and failure.
Collapse
Affiliation(s)
- M A Reynolds
- Department of Surgery, University of Louisville School of Medicine, KY 40292, USA
| | | | | | | | | | | |
Collapse
|
50
|
González C, Stec W, Reynolds MA, James TL. Structure and dynamics of a DNA.RNA hybrid duplex with a chiral phosphorothioate moiety: NMR and molecular dynamics with conventional and time-averaged restraints. Biochemistry 1995; 34:4969-82. [PMID: 7711019 DOI: 10.1021/bi00015a008] [Citation(s) in RCA: 79] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The three-dimensional structure of two thiophosphate-modified DNA.RNA hybrid duplexes d(GCTATAApsTGG).r(CCAUUAUAGC), one with R-thiophosphate chirality and one with S-thiophosphate chirality, have been determined by restrained molecular dynamics simulations (rMD). As the two yielded almost identical results, a description of results can be presented in the singular. The conformational flexibility of this hybrid has been investigated by employing time-averaged constraints during the molecular dynamics simulations (MD-tar). A set of structural restraints, comprising 322 precise interproton distance constraints obtained by a complete relaxation matrix analysis of the 2D NOE intensities as well as J coupling constants obtained from quantitative simulations of DQF-COSY cross-peaks in deoxyriboses, was reported in our previous paper [González, C., Stec, W., Kobylanska, A., Hogrefe, R. I., Reynolds, M., & James, T. L. (1994) Biochemistry 33, 11062-11072]. Multiple conformations of the deoxyribose moieties were evident from the scalar coupling constant analysis. Accurate distance constraints, obtained from complete relaxation matrix analysis, yielded a time-averaged solution structure via conventional restrained molecular dynamics which is not compatible with the experimental J coupling constants (root-mean-square deviation in J value approximately 2 Hz). However, vicinal coupling constant information can be reproduced when time-averaged constraints are used during the molecular dynamics calculations instead of the conventional restraints (Jrms approximately 0.6 Hz). MD-tar simulations also improve the NMR R factors. This improvement is more evident in the DNA than in the RNA strand, where no indication of conformational flexibility had been obtained. Analysis of the MD-tar trajectories confirms that deoxyriboses undergo pucker transitions between the S and N domain, with the major conformer in the S domain. The ribose moieties in the RNA strand, however, remain in the N domain during the entire simulation. Conformations of deoxyriboses in the intermediate domain near O4'-endo are obtained when the average structure is calculated with conventional NMR restraints. Since these conformations cannot account for the experimental J coupling information, and they only appear in a very low population in the MD-tar ensemble, we conclude that intermediate E sugar puckers are artifacts produced by the attempt to fit all the structural constraints simultaneously when in reality more than one conformer is present. Most structural features of the duplex remain the same in the average structure and in the MD-tar ensemble, e.g., the minor groove width, exhibiting an intermediate value compared with those of canonical A- and B-like structures.(ABSTRACT TRUNCATED AT 250 WORDS)
Collapse
Affiliation(s)
- C González
- Department of Pharmaceutical Chemistry, University of California, San Francisco 94143-0446, USA
| | | | | | | |
Collapse
|