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Tomé HVV, Clark SL, Jorgenson BC, Kimmel S, Wenzel B, Gimeno C, Porch J, Patnaude MR, Schmidt K, Deslandes L, Schmehl DR. Chronic larval and adult honey bee laboratory testing: Which dietary additive should be considered when a test substance is not solubilized in acetone? Ecotoxicol Environ Saf 2023; 268:115718. [PMID: 38000305 DOI: 10.1016/j.ecoenv.2023.115718] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 11/14/2023] [Accepted: 11/18/2023] [Indexed: 11/26/2023]
Abstract
Chronic toxicity tests on adult and larval honey bees (Apis mellifera) can require the use of dietary additives (solvents, emulsifiers, adjuvants and viscosifier agents) when the active ingredient of plant protection products cannot be dissolved or does not remain stable and homogeneous within the test diets. Acetone is the widely used and accepted solvent allowed within the international regulatory guidelines, but it can be ineffective in keeping certain compounds in solution and can cause toxicity to adults and larvae. In this publication, we present an evaluation of alternative additives in adult and larval diets. Six dietary additives including five solvents (ethanol, isopropanol, n-propanol, propylene glycol and triethylene glycol) and a viscosifier agent (xanthan gum) at five concentrations along with a negative control and a solvent control (acetone) were investigated at seven laboratories. The safe levels for bees were determined for each of the additives used in the 10-day chronic adult and 22-day chronic larval tests. In the 10-day chronic adult study, ethanol and isopropanol were found to be safe at concentrations ≤ 5.0 %, while xanthan gum can be reliably used at concentrations ≤ 0.1 %. Greater variability across laboratories was observed for N-propanol, propylene glycol, and triethylene glycol and these agents may cause mortality when added to diets at concentrations above 0.25-0.5 %. The safe levels of additives to larval diet in the 22-day chronic larval test had a greater variability and were generally lower than what were observed for adult diet. Our results do not recommend the inclusion of ethanol or n-propanol into the larval diet, and isopropanol, propylene glycol, and triethylene glycol may cause mortality at concentrations above 0.25-0.5 %. Safe levels for xanthan gum were more variable than what was observed for adults, but it can be used reliably at concentrations ≤ 0.05 %. Our analyses conclude that several additives can be integrated successfully in honey bee laboratory bioassays at levels that cause low mortality to adults and larvae.
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Affiliation(s)
- Hudson V V Tomé
- FMC Corporation, Newark, DE, USA; Pollinator Research Task Force (PRTF), USA
| | | | | | - Stefan Kimmel
- Corteva Agriscience, Indianapolis, IN, USA; Innovative Environmental Services IES, Witterswil, Switzerland
| | - Bettina Wenzel
- Innovative Environmental Services IES, Witterswil, Switzerland
| | | | | | | | | | - Line Deslandes
- Syntech Research Group, La Chapelle de Guinchay, France; knoell France SAS, Lyon, France
| | - Daniel R Schmehl
- Pollinator Research Task Force (PRTF), USA; Bayer CropScience LP., Chesterfield, MO, USA.
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Nassr AA, Hessami K, Berghella V, Bibbo C, Shamshirsaz AA, Shirdel Abdolmaleki A, Marsoosi V, Clark SL, Belfort MA, Shamshirsaz AA. Angle of progression measured using transperineal ultrasound for prediction of uncomplicated operative vaginal delivery: systematic review and meta-analysis. Ultrasound Obstet Gynecol 2022; 60:338-345. [PMID: 35238424 DOI: 10.1002/uog.24886] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/26/2021] [Revised: 02/17/2022] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
OBJECTIVE To determine whether intrapartum transperineal ultrasound measurement of the angle of progression (AoP) during the second stage of labor can predict uncomplicated operative vaginal delivery (OVD) using vacuum or forceps extraction. METHODS A systematic search in PubMed, EMBASE, Scopus, Web of Science and Google Scholar was performed from inception to February 2021. Studies assessing the predictive accuracy of AoP, measured using intrapartum transperineal ultrasound, for uncomplicated OVD, defined as successful vaginal delivery within three pulls using forceps or no more than two detachments of the vacuum extractor cup, were included. Study quality was assessed using the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool. Summary receiver-operating-characteristics (ROC) curves, pooled sensitivity and specificity, area under the ROC curve (AUC) and summary likelihood ratios (LRs) were calculated. RESULTS Seven studies reporting on a total of 782 patients undergoing OVD were included in this systematic review and meta-analysis. Second-stage AoP measured during maternal rest had a pooled sensitivity of 80% (95% CI, 59-92%) and specificity of 89% (95% CI, 76-95%), with a LR+ of 7.3 (95% CI, 3.1-15.8) for uncomplicated OVD. AoP measured during active pushing had a sensitivity of 91% (95% CI, 85-94%) and specificity of 83% (95% CI, 69-92%), with a LR+ of 5.4 (95% CI, 2.7-10.6) for uncomplicated OVD. The performance of AoP measured at rest was particularly high in nulliparous women, with a sensitivity of 87% (95% CI, 75-94%) and specificity of 90% (95% CI, 82-94%) for uncomplicated OVD. CONCLUSION AoP may be a reliable predictor for uncomplicated OVD when measured during the second stage of labor, especially in nulliparous women. © 2022 International Society of Ultrasound in Obstetrics and Gynecology.
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Affiliation(s)
- A A Nassr
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
- Department of Obstetrics and Gynecology, Women's Health Hospital, Assiut University, Assiut, Egypt
| | - K Hessami
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
- Maternal-Fetal Medicine Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - V Berghella
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Sidney Kimmel Medical College, Thomas Jefferson University, Philadelphia, PA, USA
| | - C Bibbo
- Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Brigham and Women's, Boston, MA, USA
| | - A A Shamshirsaz
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
| | - A Shirdel Abdolmaleki
- Maternal-Fetal Medicine Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - V Marsoosi
- Department of Obstetrics and Gynecology, Tehran University of Medical Sciences, Tehran, Iran
| | - S L Clark
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
| | - M A Belfort
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
| | - A A Shamshirsaz
- Department of Obstetrics and Gynecology, Baylor College of Medicine, Houston, TX, USA
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Donohoe RM, Duke BM, Clark SL, Joab BM, Dugan JE, Hubbard DM, DaSilva AR, Anderson MJ. Toxicity of Refugio Beach Oil to Sand Crabs (Emerita analoga), Blue Mussels (Mytilus sp.), and Inland Silversides (Menidia beryllina). Environ Toxicol Chem 2021; 40:2578-2586. [PMID: 34192809 DOI: 10.1002/etc.5148] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Revised: 05/04/2021] [Accepted: 06/28/2021] [Indexed: 06/13/2023]
Abstract
Monterey formation crude oil spilled from an onshore pipeline and entered the surf zone near Refugio State Beach, Santa Barbara County, California (USA) on 19 May 2015. During this season, early life stages of many marine fish and invertebrates were present. Surf zone water and beach porewater samples were collected during the 4 mo after the spill and 2 yr later for chemical analyses. Elevated polycyclic aromatic hydrocarbon (PAH) and total petroleum hydrocarbon concentrations were observed in surf zone water and porewater near the release point, declining with distance and time. Early life stage toxicity was investigated by conducting 6- and 7-d static renewal bioassays with sand crab (Emerita analoga) post larvae (megalopae) and inland silverside larvae (Menidia beryllina), respectively, and a 48-h blue mussel (Mytilus sp.) embryo development bioassay. Dilutions of a high-energy water accommodated fraction of the Refugio Beach oil and a seawater control were prepared to simulate surf zone PAH concentrations (nominal PAH45 ; 0, 0.5, 1, 5, 10, 50, 100, and 500 µg/L). The PAH45 median lethal concentrations (LC50s), based on measured concentrations, were 381 µg/L for Mytilus sp., 75.6 µg/L for Menidia, and 40.9 µg/L for Emerita. Our results suggest that PAH concentrations in coastal waters of the spill-affected area were potentially lethal to early life stages of fish and invertebrates. Environ Toxicol Chem 2021;40:2578-2586. © 2021 SETAC.
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Affiliation(s)
- Regina M Donohoe
- Office of Spill Prevention and Response, California Department of Fish and Wildlife, Sacramento, California, USA
| | - Bryand M Duke
- Office of Spill Prevention and Response, California Department of Fish and Wildlife, Sacramento, California, USA
| | | | - Bruce M Joab
- Office of Spill Prevention and Response, California Department of Fish and Wildlife, Sacramento, California, USA
| | - Jenifer E Dugan
- Marine Science Institute, University of California, Santa Barbara, California, USA
| | - David M Hubbard
- Marine Science Institute, University of California, Santa Barbara, California, USA
| | - April R DaSilva
- Office of Spill Prevention and Response, California Department of Fish and Wildlife, Sacramento, California, USA
| | - Michael J Anderson
- Office of Spill Prevention and Response, California Department of Fish and Wildlife, Sacramento, California, USA
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Affiliation(s)
- S L Clark
- Baylor College of Medicine/Texas Children's Hospital, Houston, Texas, USA
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Sastry AC, Gandhi M, Clark SL, Whitehead WE, Mann DG, Sutton CD. Fetal heart rate mirrors maternal temperature during posterior fossa craniotomy: a case report. Int J Obstet Anesth 2021; 47:103193. [PMID: 34144352 DOI: 10.1016/j.ijoa.2021.103193] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 04/27/2021] [Accepted: 05/19/2021] [Indexed: 11/15/2022]
Abstract
While it is well known that maternal temperature affects fetal heart rate, the exact relationship is not well described. The circumstances accompanying most cases of maternal hypothermia and rewarming (e.g. a drowning event) have precluded a precise quantitative description of this relationship. We describe hypothermia and controlled rewarming during resection of a maternal brain stem tumor in the early third trimester. Continuous electronic fetal heart rate and core temperature monitoring demonstrated a near linear relationship during the development of hypothermia and rewarming. Recognition of the close relationship between maternal temperature and fetal heart rate can help safeguard maternal and fetal health, and prevent unnecessary delivery during non-obstetric surgery in pregnancy.
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Affiliation(s)
- A C Sastry
- Department of Obstetrics and Gynecology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - M Gandhi
- Department of Obstetrics and Gynecology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - S L Clark
- Department of Obstetrics and Gynecology, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - W E Whitehead
- Department of Neurosurgery, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - D G Mann
- Department of Anesthesiology, Perioperative, and Pain Medicine, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA
| | - C D Sutton
- Department of Anesthesiology, Perioperative, and Pain Medicine, Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA.
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Clark SL, Yilmaz D, Arun K, Javadzadeh S, Saeed S, Ullah MZ. Abstract P3-03-10: Pre-operative lymphoscintigraphy for sentinel lymph node localisation: Is it necessary? Cancer Res 2019. [DOI: 10.1158/1538-7445.sabcs18-p3-03-10] [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: 11/16/2022]
Abstract
Abstract
Introduction
Sentinel lymph node biopsy (SLNB) has replaced lymph node clearance for staging of the axilla in patients with early invasive breast cancer and no evidence of lymph node involvement on ultrasound or needle biopsy. It is recommended that a dual technique, using isotope and blue dye, is used to locate the sentinel lymph node (SLN) intra-operatively. Often, at the time of radioisotope injection, a lymphoscintigram (nuclear medicine scan) is obtained to demonstrate the 'hot' sentinel lymph node with or without skin marking of its anatomical position.
Performing a lymphoscintigram adds time and cost to the localisation process. In our centre, this investigation costs £899-999 (˜US $1180-1300).
Aims
The aim of this study is to find out whether obtaining a pre-operative lymphoscintigram aids the surgeon in the localisation of the SLN or affects the number of sentinel lymph nodes biopsied in the axillary staging of patients with early invasive breast cancer.
Methods
We carried out a retrospective study of patients who underwent SLNB for breast cancer in our hospital Trust between March 2012 and November 2017. We identified those patients who had a lymphoscintigram performed pre-operatively for SLN localisation. We recorded the number of SLNs identified on imaging and compared this with the number of SLNs biopsied during the operation.
Results
349 patients underwent 354 SLNBs during the study period. One patient was male, the remainders were female. The mean age of patients was 57.2 years (range 25 to 98 years).
In 295 (83.3%) cases, a lymphoscintigram was obtained prior to SLNB for node localisation, and 268 (90.8%) of these scans were able to identify one or more SLNs. In 173 (58.6%) scans, a single SLN was identified. In 27 (9.1%) scans it was either unclear how many SLNs were demonstrated or no SLNs were seen (16/295 no SLN identified, 11/295 unclear how many SLNs).
In 102 (34.6%) cases, the number of SLNs biopsied matched the number of SLNs identified on imaging. Of those that did not match, 76.2% had more and 15.0% fewer SLNs excised than shown on imaging. In 8.8% it was unknown if the number of SLNs matched that seen on imaging due to lack of histopathology results.
Conclusion
Lymphoscintigraphy for SLN localisation is costly and time consuming. In a high proportion of cases, number of SLNs identified on imaging does not match the number biopsied and thus, we suggest, that it is not required prior to SLNB and should be removed from practice.
Citation Format: Clark SL, Yilmaz D, Arun K, Javadzadeh S, Saeed S, Ullah MZ. Pre-operative lymphoscintigraphy for sentinel lymph node localisation: Is it necessary? [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P3-03-10.
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Affiliation(s)
- SL Clark
- Whipps Cross University Hospital, Barts Health NHS Trust, London, United Kingdom
| | - D Yilmaz
- Whipps Cross University Hospital, Barts Health NHS Trust, London, United Kingdom
| | - K Arun
- Whipps Cross University Hospital, Barts Health NHS Trust, London, United Kingdom
| | - S Javadzadeh
- Whipps Cross University Hospital, Barts Health NHS Trust, London, United Kingdom
| | - S Saeed
- Whipps Cross University Hospital, Barts Health NHS Trust, London, United Kingdom
| | - MZ Ullah
- Whipps Cross University Hospital, Barts Health NHS Trust, London, United Kingdom
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Clark SL, Ramdath DD, King BV, O'Connor KE, Hawke A, Aliani M, Duncan AM. Lentils Do Not Affect Satiety or Food Intake When Substituted for Wheat Flour in a Muffin Matrix in Healthy Adults. Am J Transl Res 2018. [DOI: 10.1055/s-0038-1644944] [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: 10/28/2022]
Affiliation(s)
- SL Clark
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - DD Ramdath
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, Ontario, Canada
| | - BV King
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - KE O'Connor
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
| | - A Hawke
- Guelph Research and Development Centre, Agriculture and Agri-Food Canada, Guelph, Ontario, Canada
| | - M Aliani
- Department of Food and Human Nutritional Sciences, University of Manitoba, Winnipeg, Manitoba, Canada
| | - AM Duncan
- Department of Human Health & Nutritional Sciences, University of Guelph, Guelph, Ontario, Canada
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Clark SL. Author's reply re: UK Secretary of State for Health proposes a new model for compensating the victims of adverse outcomes due to medical/midwifery errors during childbirth and Malpractice reduction and standardisation of care; two sides of the same coin. BJOG 2017; 125:94-95. [PMID: 28972282 DOI: 10.1111/1471-0528.14910] [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] [Accepted: 08/26/2017] [Indexed: 11/28/2022]
Affiliation(s)
- S L Clark
- Maternal-Fetal Medicine, Baylor College of Medicine/Texas Children's Hospital, Houston, TX, USA
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Affiliation(s)
- S L Clark
- Baylor College of Medicine and Texas Children's Hospital, Houston, TX, USA
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10
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Rajagopalan S, Suresh M, Clark SL, Serratos B, Chandrasekhar S. Airway management for cesarean delivery performed under general anesthesia. Int J Obstet Anesth 2016; 29:64-69. [PMID: 27884665 DOI: 10.1016/j.ijoa.2016.10.007] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2016] [Revised: 09/29/2016] [Accepted: 10/20/2016] [Indexed: 11/19/2022]
Abstract
BACKGROUND With the increasing popularity of neuraxial anesthesia, there has been a decline in the use of general anesthesia for cesarean delivery. We sought to examine the incidence, outcome and characteristics associated with a failed airway in patients undergoing cesarean delivery under general anesthesia. METHODS A retrospective review of airway management in women undergoing cesarean delivery under general anesthesia over an eight-year period from 2006-2013 at an academic medical center was conducted. RESULTS During the study period, 10 077 cesarean deliveries were performed. Neuraxial anesthesia was used in 9382 (93%) women while general anesthesia was used in 695 (7%). Emergent cesarean delivery was the most common indication for general anesthesia. Failed intubation was encountered in only three (0.4%) women, who were successfully managed with a laryngeal mask airway. The overall incidence of failed intubation was 1 in 232 (95% CI 1:83 to 1:666) and general anesthesia was continued in all cases. There were no adverse maternal or fetal outcomes directly related to failed intubation. CONCLUSION Advances in adjunct airway equipment, availability of an experienced anesthesiologist and simulation-based teaching of failed airway management in obstetrics may have contributed to our improved maternal outcomes in patients undergoing cesarean delivery under general anesthesia.
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Affiliation(s)
- S Rajagopalan
- Department of Anesthesiology, Baylor College of Medicine, Houston, TX, USA.
| | - M Suresh
- Department of Anesthesiology, Baylor College of Medicine, Houston, TX, USA
| | - S L Clark
- Department of Obstetrics and Gynecology, Maternal Fetal Medicine, Baylor College of Medicine, Houston, TX, USA
| | - B Serratos
- Department of Anesthesiology, Baylor College of Medicine, Houston, TX, USA
| | - S Chandrasekhar
- Department of Anesthesiology, Baylor College of Medicine, Houston, TX, USA
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Clark SL, Ogle RS, Gantner A, Hall LW, Mitchell G, Giddings J, McCoole M, Dobbs M, Henry K, Valenti T. Comparative sensitivity of field and laboratory populations of Hyalella azteca to the pyrethroid insecticides bifenthrin and cypermethrin. Environ Toxicol Chem 2015; 34:2250-2262. [PMID: 25929226 DOI: 10.1002/etc.2907] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Revised: 10/21/2014] [Accepted: 01/22/2015] [Indexed: 06/04/2023]
Abstract
Hyalella azteca are epibenthic invertebrates that are widely used for toxicity studies. They are reported to be more sensitive to pyrethroid insecticides than most other test species, which has prompted considerable use of this species in toxicity testing of ambient surface waters where the presence of pyrethroids is suspected. However, resident H. azteca have been found in some ambient water bodies reported to contain surface water and/or sediment pyrethroid concentrations that are toxic to laboratory reared H. azteca. This observation suggests differences in the sensitivities of laboratory reared and field populations of H. azteca to pyrethroids. The goal of the present study was to determine the sensitivities of laboratory reared and field populations of H. azteca to the pyrethroids bifenthrin and cypermethrin. Specimens of H. azteca were collected from resident populations at field sites that are subject to varied land-use activities as well as from laboratory populations. These organisms were exposed to bifenthrin- or cypermethrin-spiked water in 96-h water-only toxicity tests. The resulting data demonstrated that: 1) field-collected populations in urban and agricultural settings can be >2 orders of magnitude less sensitive to the pyrethroids than laboratory reared organisms; 2) field-collected organisms varied in their sensitivity (possibly based on land-use activities), with organisms collected from undeveloped sites exhibiting sensitivities similar to laboratory reared organisms; and 3) the sensitivity of field-collected "tolerant" organisms increased in subsequent generations reared under laboratory conditions. Potential mechanisms for these differences are discussed.
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Affiliation(s)
| | | | | | | | | | - Jeffrey Giddings
- Compliance Services International, Rochester, Massachusetts, USA
| | | | - Michael Dobbs
- Bayer Crop Science, Research Triangle Park, North Carolina, USA
| | - Kevin Henry
- Syngenta Crop Protection, Greensboro, North Carolina, USA
| | - Ted Valenti
- Syngenta Crop Protection, Greensboro, North Carolina, USA
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Clark SL, Scott R, Hall LW, Mitchell G, Giddings J, Dobbs M, McCoole M, Henry K, Valenti T. The authors' reply. Environ Toxicol Chem 2015; 34:2191-2193. [PMID: 26414545 DOI: 10.1002/etc.3175] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 07/20/2015] [Indexed: 06/05/2023]
Affiliation(s)
| | - R Scott
- Pacific EcoRisk Fairfield, California, USA
| | | | | | | | - Michael Dobbs
- Bayer Crop Science Research Triangle Park, North Carolina, USA
| | - Matthew McCoole
- Bayer Crop Science Research Triangle Park, North Carolina, USA
| | | | - Ted Valenti
- Syngenta Crop Protection, Greensboro, North Carolina,, USA
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Clark SL. Cardiac disease in pregnancy - some good news. BJOG 2015; 122:1456. [PMID: 26119133 DOI: 10.1111/1471-0528.13493] [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: 10/23/2022]
Affiliation(s)
- S L Clark
- Baylor College of Medicine/Texas Children's Hospital, Houston, TX, USA
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Belfort MA, Arnold J, Clark SL. Practice may not always make perfect (outcomes). BJOG 2015; 123:119. [PMID: 25846485 DOI: 10.1111/1471-0528.13371] [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: 11/28/2022]
Affiliation(s)
- M A Belfort
- Baylor College of Medicine, Texas Medical Center, Houston, TX, USA
| | - J Arnold
- Baylor College of Medicine, Texas Medical Center, Houston, TX, USA
| | - S L Clark
- Baylor College of Medicine, Texas Medical Center, Houston, TX, USA
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Abstract
BACKGROUND Understanding individual differences in susceptibility to antidepressant therapy side-effects is essential to optimize the treatment of depression. METHOD We performed genome-wide association studies (GWAS) to search for genetic variation affecting the susceptibility to side-effects. The analysis sample consisted of 1439 depression patients, successfully genotyped for 421K single nucleotide polymorphisms (SNPs), from the Sequenced Treatment Alternatives to Relieve Depression (STAR*D) study. Outcomes included four indicators of side-effects: general side-effect burden, sexual side-effects, dizziness and vision/hearing-related side-effects. Our criterion for genome-wide significance was a prespecified threshold ensuring that, on average, only 10% of the significant findings are false discoveries. RESULTS Thirty-four SNPs satisfied this criterion. The top finding indicated that 10 SNPs in SACM1L mediated the effects of bupropion on sexual side-effects (p = 4.98 × 10(-7), q = 0.023). Suggestive findings were also found for SNPs in MAGI2, DTWD1, WDFY4 and CHL1. CONCLUSIONS Although our findings require replication and functional validation, this study demonstrates the potential of GWAS to discover genes and pathways that could mediate adverse effects of antidepressant medication.
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Affiliation(s)
- S L Clark
- Center for Biomarker Research and Personalized Medicine, Medical College of Virginia, Virginia Commonwealth University, Richmond, VA 23298-0581, USA.
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Alexopoulos E, Hope A, Clark SL, McHugh S, Hosey MT. A report on dental anxiety levels in children undergoing nitrous oxide inhalation sedation and propofol target controlled infusion intravenous sedation. Eur Arch Paediatr Dent 2007; 8:82-6. [PMID: 17555689] [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: 05/15/2023]
Abstract
AIM To report on two separate child sedation cohorts; one undergoing propofol intravenous sedation (IVS) and the other, nitrous oxide inhalation sedation (IS) in respect to changes in dental anxiety and subject characteristics. STUDY DESIGN The age, gender, level of social deprivation and amount of treatment performed and observed patient behaviour during treatment, using the Frankl and a VAS scale, were recorded for each subject. Anxiety questionnaires were completed before and after treatment. These were: - Modified Child Dental Anxiety Scale (MCDAS); Children's Fear Survey Schedule- Dental Subscale (CFSS-DS) and two Visual Analogue Scales (VAS). RESULTS AND STATISTICS Participants (36) attended for treatment under IS and 40 attended for treatment under propofol IVS. The IVS cohort was older (p<0.01), by between 1.9 and 4.1 years and had more treatment [p = 0.015, 95% confidence interval for the difference between the cohort medians was (0, 3) units]. The two cohorts were closely matched in respect to pre-operative anxiety as measured by the MCDAS and CFSS-DS scales. There were significant anxiety reductions within each cohort as measured by three of the scales: - MCDAS, CFSS-DS and VAS (1) (p< or = 0.001) but no significant change in the VAS (2) scores. When the two cohorts were compared, there was no significant difference in the reduction of the self-reported anxiety for any of the four scales (p>0.05). The observed behaviour was good for both cohorts. CONCLUSION Propofol target-controlled intravenous sedation and nitrous oxide inhalation sedation were similarly efficacious at anxiety reduction in referred dentally anxious children. Subjects undergoing propofol IVS were older than those undergoing IS. Propofol TCI may offer the opportunity for more treatment at each visit. Further propofol TCI conscious sedation studies are required.
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Affiliation(s)
- E Alexopoulos
- Dept Paediatric Dentistry, Glasgow Dental School, Glasgow, Scotland, UK
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Phelan JP, Clark SL, Diaz F, Paul RH. Vaginal birth after cesarean. Int J Gynaecol Obstet 2004. [DOI: 10.1016/0020-7292(88)90170-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Clark SL, Sabey P, Jolley K. Nonstress testing with acoustic stimulation and amniotic fluid volume assessment: 5973 tests without unexpected fetal death. Int J Gynaecol Obstet 2004. [DOI: 10.1016/0020-7292(89)90439-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Coffin SE, Clark SL. Induction of intestinal rotavirus-specific antibodies in respiratory, but not gut, lymphoid tissues following mucosal immunization of mice with inactivated rotavirus. Virology 2001; 291:235-40. [PMID: 11878893 DOI: 10.1006/viro.2001.1180] [Citation(s) in RCA: 9] [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: 11/22/2022]
Abstract
Intranasal (i.n.), but not oral, immunization of mice with inactivated rotavirus induces protection against challenge. To understand the mechanisms by which i.n. immunization with inactivated rotavirus evokes protective immunity, we examined the site of rotavirus-specific B cell activation and the origins of intestinal IgA-secreting B cells following i.n. inoculation of mice with inactivated rhesus rotavirus. We found that (1) i.n., but not oral, inoculation induced partial protection after challenge; (2) i.n., but not oral, inoculation induced production of rotavirus-specific IgM, IgA, and IgG by intestinal lymphoid tissues; and (3) after i.n. inoculation, nasal-associated lymphoid tissues (NALT) and bronchial lymph nodes (BLN) were the sites of initial production of rotavirus-specific antibodies. These studies indicate that after inoculation with inactivated rotavirus, virus-specific effector B cells may be more easily activated in respiratory, compared to intestinal, lymphoid tissues. Additional studies are needed to determine if these observations are due to fundamental differences in the microenvironment of NALT and BLN compared to Peyer's patches or are a function of the anatomic differences between the respiratory and the gastrointestinal tracts.
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Affiliation(s)
- S E Coffin
- Division of Immunologic and Infectious Diseases, The Children's Hospital of Philadelphia, 34th Street and Civic Center Boulevard, Philadelphia, PA 19104, USA.
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Clark SL, Teh SJ, Hinton DE. Tissue and cellular alterations in Asian clam (Potamocorbula amurensis) from San Francisco Bay: toxicological indicators of exposure and effect? Mar Environ Res 2000; 50:301-305. [PMID: 11460709 DOI: 10.1016/s0141-1136(00)00100-8] [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] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The US Geological Survey has reported the presence of a metal contamination gradient in clam tissues, decreased condition indices, and irregular reproductive patterns have been reported in the Asian clam, Potamocorbula amurensis, from San Francisco Bay. If metals are driving the observed patterns in the field, then biomarkers of exposure, and possibly deleterious effect, should show a corresponding gradient. In this study, biomarkers from sub-cellular to tissue levels of biological organization were assessed in P. amurensis collected from the Bay or exposed to cadmium in the laboratory. Cellular and tissue alterations were assessed using histopathology and enzyme histochemistry (EH). Alterations in the ovary, testis, kidney, and gill tissues were most common at the most contaminated station when data were averaged over a 12-month sampling period. EH analysis indicated decreased active transport, energy status, and glucose oxidation in kidney and digestive gland at the most contaminated site which may indicate a decreased potential for growth. Ovarian lesions observed in feral Asian clams were experimentally induced in healthy clams by cadmium exposure in laboratory exposures. Our results suggest a contaminant etiology for tissue alterations.
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Affiliation(s)
- S L Clark
- Aquatic Toxicology Laboratory, Department of Anatomy, Physiology and Cell Biology, School of Veterinary Medicine, University of California-Davis, Davis, CA 95616, USA
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Abstract
Coumarin derivatives are the anticoagulants most widely used in the United States. These agents are relatively contraindicated during pregnancy, and the use of these drugs in breast-feeding women remains controversial. Much of the confusion regarding the passage of these agents into breast milk might stem from the fact that different agents possess significantly different chemical properties. A review of the chemical structure of different coumarin derivatives, as well as available clinical evidence, suggests that warfarin sodium is not excreted into breast milk, and can be safely given to women requiring therapeutic anticoagulation postpartum. For the rare patient who cannot tolerate warfarin sodium, the use of dicumarol, rather than anisindione, is preferred.
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Affiliation(s)
- S L Clark
- Intermountain Health Care, The University of Utah School of Medicine, Salt Lake City, Utah, USA.
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Affiliation(s)
- G A Dildy
- University of Utah Health Sciences Center, Salt Lake City 84132, USA
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Clark SL, Scott JR, Porter TF, Schlappy DA, McClellan V, Burton DA. Is vaginal birth after cesarean less expensive than repeat cesarean delivery? Am J Obstet Gynecol 2000; 182:599-602. [PMID: 10739514 DOI: 10.1067/mob.2000.104200] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [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: 11/22/2022]
Abstract
OBJECTIVE This study was undertaken to compare total medical costs of trial of labor after cesarean with those of elective repeat cesarean without labor, with both short- and long-term neonatal costs associated with such procedures taken into account. STUDY DESIGN Costs associated with All Patient Refined diagnosis-related groups and Current Procedural Terminology for a large not-for-profit health care system were applied to an algorithm describing maternal and neonatal outcomes of trial of labor. Perinatal morbidity rates and cost estimates for long-term neurologic damage associated with uterine rupture were derived from published literature. RESULTS If a 70% vaginal birth rate for women undergoing a trial of labor and delivery in a tertiary center with a mean uterine rupture to delivery time of 13 minutes is assumed, the net cost differential ranged from a saving of $149 to a loss of $217, depending on morbidity assumptions. For vaginal birth after cesarean success rates <70%, trial of labor in the presence of two previous scars, and institutional factors increasing the perinatal morbidity rate by just 4% with respect to that seen in tertiary centers, trial of labor resulted in a net financial loss to the health care system regardless of all other assumptions made. CONCLUSIONS When costs as opposed to charges are considered and the cost of long-term care for neurologically injured infants is taken into account, trial of labor after previous cesarean is unlikely to be associated with a significant cost saving for the health care system. Recent government-mandated length-of-stay requirements are likely to make the economic benefit of vaginal birth after cesarean even less favorable. Factors other than cost must govern decisions regarding trial of labor or repeat cesarean.
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Affiliation(s)
- S L Clark
- Intermountain Health Care, University of Utah, Salt Lake City, Utah, USA
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Abstract
Both VAS and scalp stimulation are useful in the evaluation of fetal compromise by decreasing the number of falsely abnormal FHR tests and limiting the number of unnecessary interventions, thus improving the efficiency of antepartum and intrapartum FHR monitoring. As is true for all types of fetal assessment using FHR monitoring, VAS and scalp stimulation have limitations, and a lack of response to these methodologies does not necessarily indicate fetal acidemia. When either VAS or scalp stimulation is employed, one must take into consideration their respective predictive values (see Table 1). Fetal VAS or scalp stimulation should be considered as one facet of comprehensive fetal evaluation. When these techniques are used in this manner, the clinician evaluating the fetus in the antepartum or intrapartum period may prevent unnecessary intervention and improve maternal and neonatal outcome.
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Affiliation(s)
- T F Porter
- Department of Obstetrics and Gynecology, University of Utah Health Sciences Center, Salt Lake City.
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Coffin SE, Clark SL, Bos NA, Brubaker JO, Offit PA. Migration of antigen-presenting B cells from peripheral to mucosal lymphoid tissues may induce intestinal antigen-specific IgA following parenteral immunization. J Immunol 1999; 163:3064-70. [PMID: 10477570] [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] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
Parenterally administered immunizations have long been used to induce protection from mucosal pathogens such as Bordetella pertussis and influenza virus. We previously found that i.m. inoculation of mice with the intestinal pathogen, rotavirus, induced virus-specific Ab production by intestinal lymphocytes. We have now used adoptive transfer studies to identify the cell types responsible for the generation of virus-specific Ab production by gut-associated lymphoid tissue (GALT) after i.m. immunization. Three days after i.m. immunization with rotavirus, cells obtained from the draining peripheral lymph nodes of donor mice were transferred into naive recipient mice. We found that intestinal lymphocytes produced rotavirus-specific Igs (IgM, IgA, and IgG) 2 wk after transfer of either unfractionated cells, or unfractionated cells rendered incapable of cellular division by mitomycin C treatment. Additional studies demonstrated that rotavirus-specific IgA, but not IgG, was produced by intestinal lymphocytes after transfer of purified B cells. Ig allotype analysis revealed that rotavirus-specific IgA was produced by intestinal B cells of recipient origin, suggesting that migration of Ag-presenting B cells from peripheral lymphoid tissues to GALT may contribute to the generation of mucosal IgA responses after parenteral immunization. Strategies that promote Ag uptake and presentation by B cells may enhance mucosal IgA production following parenteral immunization.
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Affiliation(s)
- S E Coffin
- Division of Immunologic and Infectious Diseases, Children's Hospital of Philadelphia, PA 19104, USA.
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Abstract
OBJECTIVE The aim of this study was to measure and calculate oxygen transport variables in uncomplicated term pregnancies. STUDY DESIGN Ten normotensive primiparous women between 36 and 38 weeks' gestation underwent pulmonary and radial arterial catheterization as part of a larger study. Seven women had studies repeated at approximately 12 weeks post partum. Measurements were made with patients in the left lateral recumbent position after a 30-minute stabilization period. Cardiac output was measured with the thermodilution technique. Blood samples were obtained simultaneously from the pulmonary and radial arteries and analyzed in duplicate for oxygen content with a blood gas analyzer. RESULTS The oxygen contents of both arterial and mixed venous blood are significantly lower (P <.05) in the third trimester of pregnancy (15.96 and 11.97 mL/dL, respectively) than in the postpartum period (18.00 and 13.54 mL/dL). The fall in oxygen content during pregnancy prevents any significant increase in oxygen delivery in the third trimester (867. 59 mL/min) relative to the postpartum period (806.50 mL/min, P not significant). CONCLUSION This is the first report of directly measured oxygen transport variables in healthy pregnant women.
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Affiliation(s)
- G D Hankins
- Department of Obstetrics and Gynecology, University of Texas Medical Branch, Galveston, Texas, USA
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Abstract
OBJECTIVES Our purpose was to evaluate institutional and organizational influences on cesarean section rates in Utah and to adjust such rates for differences in patient acuity. STUDY DESIGN Data on cesarean section rates were derived from the Utah Hospital Discharge Database and adjusted for patient acuity by correcting raw cesarean rates for those patients undergoing cesarean section meeting regional gestational age transport criteria. RESULTS When analyzed by means of 1-way analysis of variance, the following factors had a significant negative correlation (P < .05) with cesarean section rate: presence of a newborn intensive care unit and maternal-fetal medicine subspecialists, presence on the medical staff of obstetrician-gynecologist(s) as opposed to family physicians only, delivery volume >1500/y, urban location, and 24-hour in-house anesthesiology. When cesarean rates were corrected for acuity, facilities with maternal-fetal medicine specialists and a newborn intensive care unit had significantly lower rates (P < .001) and more uniform rates than otherwise similar institutions. CONCLUSIONS More medically sophisticated physicians and institutions have lower cesarean rates when patient acuity is taken into account.
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Affiliation(s)
- S L Clark
- Intermountain Health Care, Utah State Department of Health, and University of Utah School of Medicine, Salt Lake City, USA
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Affiliation(s)
- M S Esplin
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City 84143, USA
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Abstract
Videoconferencing provides a useful tool for improving information flow, with clinical, educational and administrative uses being particularly relevant to rural and remote Australia. This paper describes the range of possible uses for computer-based videoconferencing and describes the authors' experience in delivering rural medical education in North Queensland via videoconference. Principles that ensure successful videoconferencing are outlined and are applicable to a variety of formats and uses. They include the need to keep it simple, the importance of thorough preparation, and ensuring that education drives technology, rather than the converse.
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Affiliation(s)
- T K Sen Gupta
- Department of General Practice and Rural Health, North Queensland Clinical School, University of Queensland, Australia
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Abstract
OBJECTIVE To measure fetal pericardial fluid in low-risk second-trimester pregnancies and to evaluate outcome for those with measurements greater than 2 mm. METHODS Five hundred and six women were referred for sonography between 16 and 25 weeks' gestation for common obstetric indications (dating, fetal survey, and placental location) unrelated to an increased risk of anomalies. All cases were evaluated with two-dimensional and M-mode real-time ultrasonography with the use of a mechanical sector transducer. The maximum distance of the fetal hypoechoic cardiac rim was recorded. We reviewed maternal and infant charts for those with measurements greater than 2 mm. RESULTS Median (range) maternal age was 25 (15-42) years. Median gravidity and parity were two (1-14) and one (0-11), respectively. Median estimated gestational age was 20.4 (16.3-24.9) weeks. Fetal pericardial fluid was seen in 360 of 506 (71%) fetuses. Of these 360 fetuses, the mean distance (+/- 2 standard deviation) of the fetal hypoechoic cardiac rim was 1.20 mm +/- 0.91 mm (95% confidence interval 1.15, 1.25). Among the 506 cases, the maximum measurement was 3 mm. Ten of the 506 (2%) cases had measurements greater than 2 mm. None of these ten fetuses had a cardiac structural abnormality or arrhythmia, and perinatal outcome was unremarkable. CONCLUSION During second-trimester fetal ultrasonographic examination, visualization of pericardial fluid up to 2 mm in the fetus with current high-resolution technology is common and should not be regarded as pathologic.
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Affiliation(s)
- D S Dizon-Townson
- Department of Obstetrics and Gynecology, University of Utah Health Sciences Center, Salt Lake City, USA.
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Abstract
A pilot study using electronic aroma detection was performed over a six-month period to assess the aroma of chronic non-healing venous leg ulcers and the effect of appropriate antibiotic therapy on modification of the aroma. Deep infection with pathogenic organisms was found on biopsy culture in 13 out of 15 patients. Odour analysis was performed at weekly intervals on the ulcer dressings using an AromaScan instrument. Data points on the aroma maps moved from their pre-treatment presentation. Alterations in aroma data correlated well with the progress of the ulcers. Aroma analysis is shown to be a potential tool in monitoring the progress towards healing of chronic venous ulcers.
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Affiliation(s)
- J E Greenwood
- Department of Burns and Plastic Surgery, Booth Hall Children's Hospital, Manchester
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Dildy GA, Clark SL, Garite TJ, Porter TF, Swedlow DB, Varner MW. Current status of the multicenter randomized clinical trial on fetal oxygen saturation monitoring in the United States. Eur J Obstet Gynecol Reprod Biol 1997; 72 Suppl:S43-50. [PMID: 9134412 DOI: 10.1016/s0301-2115(97)02717-6] [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] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
Current clinical methods of intrapartum fetal assessment are sensitive but poorly specific in detecting fetal compromise during labor. These limitations have substantially contributed to the escalating cesarean section rate which occurred in the US during the last several decades. Experimental and clinical research efforts directed towards application of the oxygen saturation monitor (pulse oximeter) to intrapartum fetal assessment have produced encouraging results. If this new method of fetal assessment is to enter the clinical arena, safety and efficacy issues must first be properly evaluated via randomized clinical trials. The purpose of this report is to describe the design of a multicenter randomized clinical trial of intrapartum fetal oxygen saturation monitoring recently begun in the US. Specific aspects of the trial, including purpose, study design, sample size estimates, control and test groups, inclusion and exclusion criteria, fetal heart rate classification, definition of normal fetal arterial oxygen saturation (SpO2), clinical management protocol, and assessment of maternal-fetal outcomes will be addressed.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City 84132, USA
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Porter TF, Clark SL, Oshiro BT, Dildy GA, Varner MW, Branch DW, Tooke-Miller C. Survival and neurologic outcome of apparently stillborn infants. Am J Obstet Gynecol 1997. [DOI: 10.1016/s0002-9378(97)80106-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Dildy GA, Judd VE, Clark SL. Prospective evaluation of the antenatal incidence and postnatal significance of the fetal echogenic cardiac focus: a case-control study. Am J Obstet Gynecol 1996; 175:1008-12. [PMID: 8885766 DOI: 10.1016/s0002-9378(96)80043-3] [Citation(s) in RCA: 44] [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: 02/02/2023]
Abstract
OBJECTIVE We evaluated the antenatal incidence and postnatal significance of echogenic cardiac foci observed during antenatal ultrasonography. STUDY DESIGN During a 4-month period, all women undergoing dating ultrasonography between 16.0 and 24.9 weeks' gestation at one referral center were prospectively evaluated for an echogenic cardiac focus during an apical four-chamber view of the heart. Referrals for maternal or fetal complications were excluded. Postnatal echocardiography was performed for those identified with positive findings. Controls were selected from among normal subjects in the general group for comparison with the study group. RESULTS Five hundred six consecutive fetuses were evaluated at a mean +/- SD gestational age of 20.6 +/- 1.6 weeks. There were 25 (4.9%) fetuses found to have echogenic cardiac focus (left ventricle = 19, right ventricle = 6). Echocardiography was performed between 0.3 and 20.1 weeks postdelivery. After birth, 12 echogenic left ventricle papillary muscles and three echogenic left ventricle chordae were identified; there were no postnatal right ventricle findings. There were no cases of intracardiac tumor or myocardial dysfunction; one neonate had minor structural malformations. There were no significant differences in maternal age, gravidity, parity, gestational age at ultrasonography, gestational age at delivery, or 5-minute Apgar scores. A significant difference was observed in birth weight between the control (n = 50) and study (n = 25) groups (3465 +/- 501 gm vs 3124 +/- 589 gm; p = 0.002). This difference persisted after correcting for gestational age, although all infants in both groups born after 37.0 weeks weighed > 2500 gm. CONCLUSIONS The incidence of echogenic cardiac foci during routine midtrimester ultrasonography is 4.9%. As an isolated finding, the echogenic cardiac focus may be associated with a statistically significant but clinically insignificant decrease in birth weight. Because of these findings, we consider an isolated echogenic cardiac focus in a patient at low risk for cardiac abnormalities a variant of normal, which does not warrant follow-up clinical evaluation.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, USA
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Abstract
OBJECTIVE Our purpose was to describe the maternal and fetal outcomes of pregnancies in women > or = 45 years old at delivery. STUDY DESIGN A retrospective review of in-hospital deliveries after 20 weeks of gestation was performed in four Utah tertiary care hospitals for the 10-year period between 1985 and 1994. RESULTS Seventy-nine cases were identified among 126,500 births, with an incidence of 0.63 per 1000 births. Maternal ages were 45 (n = 44), 46 (n = 21), and > or = 47 (n = 14) years. Three of the conceptions were assisted, including both twin gestations. Thirty-seven (46.8%) had obstetric complications during pregnancy; the most frequent complications were gestational diabetes (12.7%) and preeclampsia (10.1%). Median (range) gestational age at delivery was 39 (22.9 to 41.7) weeks; 12 (15.2%) deliveries occurred before 37 weeks. Eight (9.9%) karyotype abnormalities were diagnosed. The cesarean section rate was 31.7%; the most frequent indications were abnormal lie (n = 9), fetal distress (n = 5), and previous cesarean delivery (n = 5). There were no maternal deaths. Median (range) birth weight was 3466 (397 to 5085) gm; 14 (17.3%) were < 2500 gm and 16 (19.8%) were > 4000 gm. Twelve (14.8%) infants were admitted to the neonatal intensive care unit. The corrected perinatal mortality rate was 1.3% (1/78). CONCLUSIONS In women > 45 years old at delivery maternal and fetal outcomes were generally good, but there was a high incidence of pregestational (chronic hypertension, hypothyroidism) and gestational (karyotype abnormalities, gestational diabetes, cesarean section, macrosomia) complications. This information may be helpful for counseling women between 45 and 50 years old who are considering pregnancy.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, USA
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Dildy GA, Thorp JA, Yeast JD, Clark SL. The relationship between oxygen saturation and pH in umbilical blood: implications for intrapartum fetal oxygen saturation monitoring. Am J Obstet Gynecol 1996; 175:682-7. [PMID: 8828434 DOI: 10.1053/ob.1996.v175.a74922] [Citation(s) in RCA: 69] [Impact Index Per Article: 2.5] [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: 02/02/2023]
Abstract
OBJECTIVE Our purpose was to evaluate the relationship between umbilical arterial blood oxygen saturation determined by hemoximetry (Sao2) and umbilical arterial blood pH and base excess determined by blood gas analysis to establish a "critical threshold" for fetal preductal arterial oxygen saturation determined by reflectance pulse oximetry (Spo2). STUDY DESIGN Umbilical artery and vein blood specimens were obtained at delivery. Blood gas analysis and hemoximetry were performed. Polynomial regression analysis and receiver-operator characteristic curves were calculated for umbilical arterial blood Sao2 and theoretic preductal arterial blood Sao2 versus umbilical arterial blood pH and base excess. RESULTS A total of 1101 paired umbilical artery and vein specimens were obtained. When the umbilical arterial blood Sao2 was > or = 30%, umbilical arterial blood pH was > or = 7.13 in 99.0% (388/392) of cases and < 7.13 in 1.0% (4/392) of cases. When umbilical arterial blood Sao2 was < 30%, umbilical arterial blood pH was > or = 7.13 in 91.4% (648/709) of cases and < 7.13 in 8.6% (61/709) of cases. CONCLUSIONS From these analyses, it appears that an Spo2 cutoff value of 30% would be reasonable in clinical trials of intrapartum fetal pulse oximetry.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Missouri School of Medicine, Saint Luke's Hospital of Kansas City, Missouri, USA
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Hankins GD, Harvey CJ, Clark SL, Uckan EM, Van Hook JW. The effects of maternal position and cardiac output on intrapulmonary shunt in normal third-trimester pregnancy. Obstet Gynecol 1996; 88:327-30. [PMID: 8752233 DOI: 10.1016/0029-7844(96)00212-8] [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] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To assess the effect of pregnancy, maternal position, and cardiac output on intrapulmonary shunting (Qs/Qt) in normotensive nulliparous women near term. METHODS Ten normotensive nulliparas between 36 and 38 weeks' gestation underwent pulmonary artery catheterization (via the subclavian route) and radial artery canalization. Baseline assessments were made with subjects in the left lateral recumbent position after a 30-minute stabilization period. Measurements were obtained sequentially in the left lateral, right lateral, supine, knee-chest, sitting, and standing positions. Each position change was followed by a 10-minute pre-measurement stabilization period. Cardiac output was measured via the thermodilution technique. Blood samples were obtained simultaneously from the pulmonary and radial arteries and analyzed in duplicate for oxygen content with a blood gas analyzer. Qs/Qt was calculated using the classic shunt equation. Statistical analysis was performed by analysis of variance of repeated measures of Qs/Qt and maternal position. The relationship of Qs/Qt to maternal cardiac output was evaluated by the correlation coefficient. Significance was defined as P < .05. RESULTS Directly measured Qs/Qt averaged 15.3% in left lateral, 15.2% in right lateral, 13.9% in supine, 12.8% in knee-chest, 13.8% in sitting, and 13.0% in standing positions. There was no statistically significant correlation between Qs/Qt and cardiac output (R2 = 0.11, not significant). CONCLUSION This is the first report of directly measured Qs/Qt in normal pregnant women in the third trimester. Qs/Qt values reported in pregnancy are higher than those reported in nonpregnant individuals.
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Affiliation(s)
- G D Hankins
- University of Texas Medical Branch at Galveston, USA
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Hankins GD, Clark SL, Harvey CJ, Uckan EM, Cotton D, Van Hook JW. Third-trimester arterial blood gas and acid base values in normal pregnancy at moderate altitude. Obstet Gynecol 1996; 88:347-50. [PMID: 8752237 DOI: 10.1016/0029-7844(96)00210-4] [Citation(s) in RCA: 15] [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: 02/02/2023]
Abstract
OBJECTIVE To report arterial blood gas and acid base values of normal nulliparous patients at moderate altitude for commonly used maternal positions. METHODS Ten normotensive nulliparous women between 36 and 38 weeks' gestation volunteered to undergo radial and pulmonary artery cannulation as part of a larger study. Following instrumentation, baseline assessments were made in the left lateral recumbent position after a 30-minute stabilization period. Sequential measurements were then obtained in the left lateral, right lateral, supine, knee-chest, sitting, and standing positions. Blood samples were analyzed in duplicate for oxygen content on a blood gas analyzer. Statistical analysis was performed by analysis of variance of repeated measures with significance defined at P < or = .05. RESULTS There was no significant difference in arterial blood gas or acid base values between any positions in this antepartum population of term healthy women. The composite mean values were as follows: pH 7.46, arterial carbon dioxide pressure (PaCO2) 26.6 mmHg, arterial oxygen pressure 88.3 mmHg, bicarbonate 18.2 mEq/L, saturated arterial hemoglobin level 0.96. CONCLUSION Arterial blood gas and acid base values are not altered by maternal position in the late third trimester of pregnancy. The PaO2 in these women studied at moderate altitude was lower than previously reported for healthy pregnant women studied at sea level. Appropriate interpretation of arterial blood specimens of pregnant women should take into account both the pregnancy and altitude at which the women reside.
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Affiliation(s)
- G D Hankins
- University of Texas Medical Branch at Galveston, USA
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39
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Abstract
Oxygen saturation monitoring (pulse oximetry) has markedly improved medical care in many fields, including anesthesiology, critical care, and newborn intensive care. In obstetrics, fetal heart rate monitoring remains the standard for intrapartum assessment of fetal well-being. Fetal heart rate monitoring is sensitive but nonspecific for detecting fetal compromise. Additional clinical information is needed to discern those fetuses not at risk for development of intrapartum acidosis to avoid unnecessary intervention. Fetal oxygen saturation monitoring is a new technique currently under development. This article reviews the evolution of intrapartum fetal oxygen saturation monitoring and proposes directions for future investigation.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, USA
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Singh PR, Rajopadhye M, Clark SL, Williams NE. Effect of scavengers in acidolytic cleavage of Cys(Acm)-containing peptides from solid support: Isolation of an ethanedithiol disulfide adduct. Tetrahedron Lett 1996. [DOI: 10.1016/0040-4039(96)00614-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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41
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Abstract
OBJECTIVE To establish the gestational age trends of amniotic fluid index (AFI) in uncomplicated twin pregnancies. METHODS Amniotic fluid index was measured in uncomplicated twin pregnancies seen between 1985 and 1993 and meeting the following criteria: 1) no maternal medical or obstetric complications, 2) normal growth of both twins by serial ultrasound, and 3) normal amniotic fluid volume by ultrasound. Amniotic fluid index was measured by adding the deepest vertical pockets in four quadrants, defined by the umbilicus and linea nigra. The relation between gestational age and AFI was evaluated using linear regression analysis. RESULTS Two hundred eighty-two sets of twins were considered uncomplicated; 1101 AFI measurements were performed on these pregnancies between 25.5 and 40.5 weeks' gestation. Percentile values for AFI were determined according to gestational age. The regression equation relating the median AFI to gestational age was: AFI = 19.4 - 0.12 x gestational age (P = .03). The R2 value was 0.04. CONCLUSION Gestational age trends in normative AFI measurements for twin pregnancies have been established. Their use will facilitate a more reproducible, quantitative diagnosis of oligohydramnios in twins, compared with subjective, qualitative approaches to amniotic fluid volume assessment.
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Affiliation(s)
- T F Porter
- Department of Obstetrics and Gynecology, University of Utah, Salt Lake City, USA
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42
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Abstract
Our purpose was: (1) to determine whether assessment of amniotic fluid index in high risk patients with a reactive nonstress test (NST) allowed improved recognition of the fetus at risk for perinatal morbidity than a reactive NST alone; and (2) to determine the optimal low amniotic fluid index (AFI) which should prompt clinical concern. The last NST performed within a week of delivery and amniotic fluid index were retro-spectively compared with various indices of perinatal morbidity. In fetuses with a reactive NST, decreasing AFI was directly correlated with a risk of 5-minute Apgar score of less than 7 and delivery for fetal distress. When various subgroupings of AFI were compared, 7 cm or greater appeared to have a better inverse correlation with the indices of morbidity than lower cut-off values. The addition of AFI assessment to the standard NST allows better prediction of perinatal morbidity than the NSTs alone. Seven centimeters appears to be a reasonable cut-off for clinical concern.
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Varner MW, Dildy GA, Hunter C, Dudley DJ, Clark SL, Mitchell MD. Amniotic fluid epidermal growth factor levels in normal and abnormal pregnancies. J Soc Gynecol Investig 1996; 3:17-9. [PMID: 8796801 DOI: 10.1016/1071-5576(95)00044-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To determine the concentrations of epidermal growth factor (EGF) in amniotic fluid (AF) from women during late pregnancy, with and without pathophysiologic complications. METHODS All AFs were collected by amniocentesis from the following groups: gestational age at least 38 weeks (n = 15); gestational age 36-37 weeks (n = 10); gestational age 35 weeks (n = 5); labor 34 weeks or less, delivered within 7 days (n = 10); labor 34 weeks or less, undelivered (n = 10); chorioamnionitis (n = 7); gestational age-matched controls (n = 7); term, in labor (n = 8); term, not in labor (n = 8); intrauterine growth restriction (IUGR) 38 weeks or more (n = 8); macrosomia at 38 weeks or more (n = 10). Epidermal growth factor was assayed using a specific radioimmunoassay. RESULTS Amniotic fluid EGF levels increase rapidly in late pregnancy but are not altered by chorioamnionitis or by term or preterm labor. Intrauterine growth restriction is associated with lower EGF levels in AF, but macrosomia is without effect. CONCLUSIONS Epidermal growth factor levels in AF are increased near term and decreased in pregnancies complicated by IUGR; they may be an indicator of specific maturational events.
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Affiliation(s)
- M W Varner
- Department of Obstetrics and Gynecology, University of Utah, Salt Lake City, USA
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44
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Dildy GA, Clark SL. Cardiac arrest during pregnancy. Obstet Gynecol Clin North Am 1995; 22:303-14. [PMID: 7651673] [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: 01/26/2023]
Abstract
Cardiac arrest occurs rarely in pregnancy. Nevertheless, the practicing obstetrician stands a likely chance of encountering this acute condition at least once over the course of a busy career. A basic understanding of maternal-fetal physiology and the acute management of cardiac arrest are of key importance. ECC is not significantly changed from that administered to the nonpregnant patient. Factors unique to pregnancy, however, such as lateral uterine displacement, effects of drugs on the mother and the fetus, and the issues of perimortem cesarean section should be understood by the consulting obstetrician. The critical period in management of these patients is within the first several minutes of the event. In many situations, the obstetrician may be the first to arrive and initiate therapy before the arrival of multidisciplinary assistance. Prompt initial management will give the mother and fetus the best chances for survival.
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Affiliation(s)
- G A Dildy
- University of Utah Medical Center, Salt Lake City, USA
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45
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Abstract
OBJECTIVE We analyzed the clinical course and investigated possible pathophysiologic mechanisms of amniotic fluid embolism. STUDY DESIGN We carried out a retrospective review of medical records. Forty-six charts were analyzed for 121 separate clinical variables. RESULTS Amniotic fluid embolism occurred during labor in 70% of the women, after vaginal delivery in 11%, and during cesarean section after delivery of the infant in 19%. No correlation was seen with prolonged labor or oxytocin use. A significant relation was seen between amniotic fluid embolism and male fetal sex. Forty-one percent of patients gave a history of allergy or atopy. Maternal mortality was 61%, with neurologically intact survival seen in 15% of women. Of fetuses in utero at the time of the event, only 39% survived. Clinical and hemodynamic manifestations were similar to those manifest in anaphylaxis and septic shock. CONCLUSIONS Intact maternal or fetal survival with amniotic fluid embolism is rare. The striking similarities between clinical and hemodynamic findings in amniotic fluid embolism and both anaphylaxis and septic shock suggest a common pathophysiologic mechanism for all these conditions. Thus the term amniotic fluid embolism appears to be a misnomer.
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Affiliation(s)
- S L Clark
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City, USA
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46
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Abstract
Oxidized low-density lipoprotein (LDL) inhibits signalling pathways mediated by pertussis toxin-sensitive guanine nucleotide-binding proteins (Gi proteins). To determine whether this inhibition is due to altered G protein alpha i subunit expression, mRNA and protein levels of alpha i isoforms were assessed in bovine aortic endothelial cells treated with oxidized LDL (0-100 micrograms/ml, 0-72 h). Oxidized LDL did not affect the expression of alpha i3, but did cause time- and concentration-dependent decrease in alpha i2 mRNA and protein resulting in a 3.2- and 3.5-fold reduction, respectively, after 72 h. This decrease in alpha i2 coincided with a 86% decrease in alpha i2 GTPase activity. Nuclear run-off studies did not show any significant effect of oxidized LDL on alpha i2 or alpha i3 transcription. In the presence of actinomycin D, oxidized LDL shortened the t1/2 of alpha i2 mRNA from 16 h to 8 h which was attenuated by cycloheximide. In addition, pulse-chase labelling with [35S]methionine revealed that oxidized LDL reduced the t1/2 of alpha i2 protein from 27 to 14 h. Our results indicate that oxidized LDL can modulate receptor-Gi coupling by downregulating the expression of alpha i2, but not alpha i3. The mechanism involves both mRNA destabilization and protein degradation.
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Affiliation(s)
- J K Liao
- Cardiovascular Division, Brigham & Women's Hospital, Boston, Massachusetts, USA
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Abstract
The atherogenic effects of low-density lipoprotein (LDL) may be mediated, in part, by its effect(s) on endothelial-derived nitric oxide (NO). To determine whether LDL can modulate NO production by changing NO synthase expression, we treated human saphenous vein endothelial cells with increasing concentrations of native or oxidized LDL (0-100 micrograms/ml) for various durations (0-72 h). Oxidized, but not native LDL caused a time-dependent decrease in steady-state NO synthase mRNA levels. This coincided with a maximal 56% decrease in NOS activity was determined by [3H]arginine to [3H]citrulline conversion. In the presence of actinomycin D, treatment with oxidized LDL reduced the half-life of NO synthase mRNA from 36 to 10 h. This decrease in NO synthase mRNA correlated with the degree of LDL oxidation and was attenuated by pretreatment with cycloheximide. Nuclear run-off studies showed a biphasic transcriptional pattern of NO synthase gene with an initial 25% decrease during the first 6 h followed by a maximal 2.2-fold increase over baseline during the subsequent 18 h. These results indicate that oxidized LDL regulates endothelial NOS expression through a combination of early transcriptional inhibition and post-transcriptional mRNA destabilization.
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Affiliation(s)
- J K Liao
- Cardiovascular Division, Brigham & Women's Hospital, Boston, Massachusetts 02115
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48
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Abstract
Brachial plexus injuries sustained at birth have most often been attributed to the maneuvers performed when attempting to relieve a shoulder dystocia or to deliver a breech vaginally. In the case now reported, the brachial plexus injury involved the posterior shoulder. As the delivery was spontaneous and without forceps or manual rotation, with delivery effected using only the McRobert's maneuver, it is hypothesized that maternal expulsive forces in conjunction with lodging of the posterior shoulder on the sacral promontory resulted in the injury.
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Affiliation(s)
- G D Hankins
- Department of Obstetrics and Gynecology, Wilford Hall Medical Center, San Antonio, Texas 78236-5300, USA
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49
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Abstract
OBJECTIVE Our purpose was to observe the effects of maternal oxygen administration on fetal arterial oxygen saturation in normal human fetuses during labor. STUDY DESIGN Twenty healthy women with uncomplicated pregnancies were studied during active labor at term. Arterial oxygen saturation was measured by a noninvasive reflectance pulse oximeter designed for fetal application (Nellcor, Inc, Pleasanton, Calif.). The first group was studied during 20-minute intervals of inspired oxygen concentrations of 21%, 40%, and 100%. In a second group the effects of prolonged (45 minutes) supplemented 40% oxygen administration were evaluated. Differences between groups were analyzed by analysis of variance; significance was considered at p < 0.05. RESULTS A significant increase in fetal arterial oxygen saturation (50% +/- 8% vs 64% +/- 6%, p < 0.0001) was detected in the group given 100% oxygen for 20 minutes but not in the groups that received 40% oxygen for 20 or 45 minutes. CONCLUSIONS Prolonged maternal administration of 40% oxygen resulted in no significant demonstrable change in fetal arterial oxygen saturation determined by reflectance pulse oximetry in normal fetuses. Because the administration of oxygen by standard mask techniques rarely results in 40% inspired oxygen concentration, fetal benefits of such intrapartum maternal oxygen administration are questionable.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City
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Dildy GA, van den Berg PP, Katz M, Clark SL, Jongsma HW, Nijhuis JG, Loucks CA. Intrapartum fetal pulse oximetry: fetal oxygen saturation trends during labor and relation to delivery outcome. Am J Obstet Gynecol 1994; 171:679-84. [PMID: 8092214 DOI: 10.1016/0002-9378(94)90081-7] [Citation(s) in RCA: 97] [Impact Index Per Article: 3.2] [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: 01/28/2023]
Abstract
OBJECTIVES Our purpose was to study fetal arterial oxygen saturation trends by continuous pulse oximetry during labor in subjects with normal and abnormal delivery outcomes. STUDY DESIGN Continuous fetal arterial oxygen saturation was measured during labor with a noninvasive reflectance pulse oximeter designed for fetal application. Averaged arterial oxygen saturation values were compared between stage 1 and stage 2 of labor, with stage 1 further subdivided into early (< or = 4 cm), middle (5 to 7 cm), and late (8 to 10 cm) phases. Delivery outcome was considered to be abnormal for any of the following conditions: gestational age < 37 weeks, maternal oxygen administration, delivery by cesarean section, 5-minute Apgar score < 7, umbilical artery pH < 7.10, birth weight < 2500 gm, or newborn intensive care unit admission. RESULTS A total of 291 subjects were studied: 142 in Provo, 90 in Nijmegen and 59 in San Francisco. Subjects with delivery complications (n = 125) were evaluated separately from those with normal delivery outcomes (n = 160). Fetal arterial oxygen saturation was 58% +/- 10% (mean +/- SD) during the cumulative period of study for the normal-outcome group. A significant decrease (paired t test, p < 0.001) in fetal arterial oxygen saturation occurred from stage 1 (59% +/- 10%) to stage 2 (53% +/- 10%) labor. When stage 1 was subdivided into early (< or = 4 cm), middle (5 to 7 cm), and late (8 to 10 cm) phases, a gradual decreasing trend in fetal arterial oxygen saturation was observed: 62% +/- 9%, 60% +/- 11%, and 58% +/- 10%. CONCLUSIONS With the use of reflectance pulse oximetry, a statistically significant decrease in fetal arterial oxygen saturation was observed during labor in women with normal and abnormal delivery outcomes.
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Affiliation(s)
- G A Dildy
- Department of Obstetrics and Gynecology, University of Utah School of Medicine, Salt Lake City
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