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Sociocultural and Economic Disparities in Physical Therapy Utilization Among Insured Older Adults With Rheumatoid Arthritis. J Rheumatol 2023; 50:1414-1421. [PMID: 37527853 DOI: 10.3899/jrheum.2023-0103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/31/2023] [Indexed: 08/03/2023]
Abstract
OBJECTIVE To examine influences of sociocultural and economic determinants on physical therapy (PT) utilization for older adults with rheumatoid arthritis (RA). METHODS In these annual cross-sectional analyses between 2012 and 2016, we accessed Medicare enrollment data and fee-for-service claims. The cohort included Medicare beneficiaries with RA based on 3 diagnosis codes or 2 codes plus a disease-modifying antirheumatic drug medication claim. We defined race and ethnicity and dual Medicare/Medicaid coverage (proxy for income) using enrollment data. Adults with a Current Procedural Terminology code for PT evaluation were classified as utilizing PT services. Associations between race and ethnicity and dual coverage and PT utilization were estimated with logistic regression analyses. Potential interactions between race and ethnicity status and dual coverage were tested using interaction terms. RESULTS Of 106,470 adults with RA (75.1% female; aged 75.8 [SD 7.3] years; 83.9% identified as non-Hispanic White, 8.8% as non-Hispanic Black, 7.2% as Hispanic), 9.6-12.5% used PT in a given year. Non-Hispanic Black (adjusted odds ratio [aOR] 0.77, 95% CI 0.73-0.82) and Hispanic (aOR 0.92, 95% CI 0.87-0.98) individuals had lower odds of PT utilization than non-Hispanic White individuals. Adults with dual coverage (lower income) had lower odds of utilization than adults with Medicare only (aOR 0.44, 95% CI 0.43-0.46). There were no significant interactions between race and ethnicity status and dual coverage on utilization. CONCLUSION We found sociocultural and economic disparities in PT utilization in older adults with RA. We must identify and address the underlying factors that influence these disparities in order to mitigate them.
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Federal Nursing Home Policies on Antipsychotics had Similar Impacts by Race and Ethnicity for Residents With Dementia. J Am Med Dir Assoc 2023; 24:1283-1289.e4. [PMID: 37127131 PMCID: PMC10523862 DOI: 10.1016/j.jamda.2023.03.027] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 02/15/2023] [Accepted: 03/20/2023] [Indexed: 05/03/2023]
Abstract
OBJECTIVES Federal initiatives have been successful in reducing antipsychotic exposure in nursing home residents with dementia. We assessed if these initiatives were implemented equally across racial and ethnic minority groups. DESIGN Retrospective, cross-sectional trends study. SETTING AND PARTICIPANTS National long-stay nursing home residents with dementia from 2011 to 2017. METHODS We examined trends in psychotropic drug class exposures from the Minimum Data Set assessments for non-Hispanic Black (NHB), Hispanic, and non-Hispanic White (NHW) residents using interrupted time-series analyses with age-sex standardized quarterly outcomes and time points to denote the National Partnership (2012) and Five Star Rating changes (2015). RESULTS Initially, antipsychotic (33.0%) and sedative (6.8%) exposure was highest for Hispanic residents; antidepressant (59.8%) and anxiolytic (23.4%) exposure was highest for NHW residents; NHB residents had the lowest use of each. Antipsychotic use dropped at the time of the Partnership (β = -0.8807, P = .0023) and the slope declined further after the Partnership (β = -0.6611, P < .0001) for NHW. In comparison to NHW, the level and slope changes for NHB and Hispanics were not significantly different. The Five Star Rating change did not impact the level of antipsychotic use (β = 0.027, P = .9467), but the slope changed to indicate a slowed rate of decline (β = 0.1317, P = .4075) for NHW. As to the other psychotropic drug classes, there were few significant differences between trends seen in the racial and ethnic subgroups. The following exceptions were noted: antidepressant use decreased at a faster rate for NHB residents post-Partnership (β = -0.1485, P = .0371), and after the Five Star Rating change, NHB residents (β = -0.0428, P = .0312) and Hispanic residents (β = -0.0834, P < .0001) saw antidepressant use decrease faster than NHW. Sedative use in slope post-Partnership period (β = -0.086, P = .0275) and post-Five Star Rating (β = -0.0775, P < .0001) declined faster among Hispanic residents. CONCLUSIONS AND IMPLICATIONS We found little evidence of clinically meaningful differences in changes to 4 classes of psychotropic medication use among racial and ethnic minority nursing home residents with dementia following 2 major federal initiatives.
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Potentially Harmful Medication Prescribing by the Degree of Physician Specialization in Nursing Home Practice: An Observational Study. J Am Med Dir Assoc 2023; 24:1240-1246.e2. [PMID: 37088104 PMCID: PMC10524654 DOI: 10.1016/j.jamda.2023.03.017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 02/14/2023] [Accepted: 03/12/2023] [Indexed: 04/25/2023]
Abstract
OBJECTIVES The use of anticholinergics, antipsychotics, benzodiazepines, and other potentially harmful medications (PHMs) is associated with particularly poor outcomes in nursing home (NH) residents with Alzheimer's disease and related dementias (ADRD). Our objective was to compare PHM prescribing by NH physicians and advanced practitioners who focus their practice on NH residents (NH specialists) vs non-NH specialists. DESIGN Retrospective cohort study. SETTING AND PARTICIPANTS We included a 20% random sample of Medicare beneficiaries with ADRD who resided in 12,278 US NHs in 2017. Long-stay NH residents with ADRD were identified using MDS, Medicare Parts A and B claims. Residents <65 years old or without continuous Part D coverage were excluded. METHODS Physicians in generalist specialties and advanced practitioners with ≥90% of Part B claims for NH care were considered NH specialists. Residents were assigned to NH specialists vs non-NH specialists based on plurality of Part D claims submitted for that resident. Any PHM use (defined using the Beers Criteria) and the proportion of NH days on a PHM were modeled using generalized estimating equations. Models included resident demographics, clinical characteristics, cognitive and functional status, behavioral assessments, and facility characteristics. RESULTS Of the 54,713 residents in the sample, 27.9% were managed by an NH specialist and 72.1% by a non-NH specialist. There was no statistically significant difference in any PHM use [odds ratio (OR) 0.97, 95% CI 0.93-1.02, P = .23]. There were lower odds of prolonged PHM use (OR 0.87, 95% CI 0.81-0.94, P < .001, for PHM use on >75% vs >0%-<25% of NH days) for NH specialists vs non-NH specialists. CONCLUSIONS AND IMPLICATIONS Although the use of PHMs among NH residents with ADRD managed by NH specialists was not lower, they were less likely to receive PHMs over longer periods of time. Future work should evaluate the underlying causes of these differences to inform interventions to improve prescribing for NH residents.
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State Variation in Antipsychotic Use Among Assisted Living Residents With Dementia. J Am Med Dir Assoc 2023; 24:555-558.e1. [PMID: 36841263 PMCID: PMC10089770 DOI: 10.1016/j.jamda.2023.01.014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2022] [Revised: 12/19/2022] [Accepted: 01/18/2023] [Indexed: 02/25/2023]
Abstract
OBJECTIVES More than two-thirds of assisted living (AL) residents have dementia or cognitive impairment and antipsychotics are commonly prescribed for behavioral disturbances. As AL communities are regulated by state-level policies, which vary significantly regarding the care for people with dementia, we examined how antipsychotic prescribing varied across states among AL residents with dementia. DESIGN This was an observational study using 20% sample of national Medicare data in 2017. SETTING AND PARTICIPANTS The study cohort included Medicare beneficiaries with dementia aged 65 years or older who resided in larger (≥25-bed) ALs in 2017. METHODS The study outcome was the percentage of eligible AL person-months in which antipsychotics were prescribed for each state. We used a random intercept linear regression model to shrink estimates toward the overall mean use of antipsychotics addressing unstable estimates due to small sample sizes in some states. RESULTS A total of 20,867 AL residents with dementia were included in the analysis, contributing to 194,718 person-months of observation. On average, AL residents with dementia were prescribed antipsychotics during 12.6% of their person-months. This rate varied significantly by state, with a low of 7.8% (95% CI 5.9%-10.3%) for Hawaii to a high of 20.5% (95% CI 16.4%-25.3%) for Wyoming. CONCLUSIONS AND IMPLICATIONS We observed significant state variation in the prescribing of antipsychotics among AL residents with dementia using national data. These variations may reflect differences in state regulations regarding the care for AL residents with dementia and suggest the need for further investigation to ensure high quality of care.
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Psychotropic medication prescribing in assisted living and nursing home residents with dementia after the National Partnership. J Am Geriatr Soc 2022; 70:3513-3525. [PMID: 35984088 PMCID: PMC9771901 DOI: 10.1111/jgs.18004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2022] [Revised: 06/30/2022] [Accepted: 07/27/2022] [Indexed: 12/24/2022]
Abstract
BACKGROUND The Centers for Medicare & Medicaid Services implemented the National Partnership to Improve Dementia Care in Nursing Homes (the Partnership) to decrease antipsychotic use and improve care for nursing home (NH) residents with dementia. We determined whether the extent of antipsychotic and other psychotropic medication prescribing in AL residents with dementia mirrored that of long-stay NH (LSNH) residents after the Partnership. METHODS Using a 20% sample of fee-for-service Medicare beneficiaries with Part D, we conducted a retrospective cohort study including AL and LSNH residents with dementia. The monthly prevalence of psychotropic medication prescribing (antipsychotics, antidepressants, anxiolytics/sedative-hypnotics, anticonvulsants/mood stabilizers, benzodiazepines, and antidementia medications) was examined. We used an interrupted time-series analysis to compare medication prescribing before (July 1, 2010-March 31, 2012) and after (April 1, 2012-December 31, 2017) the Partnership in both settings. RESULTS We identified 107,931 beneficiaries with ≥1 month as an AL resident and 323,766 beneficiaries with ≥1 month as a LSNH resident with dementia, including 1,923,867 person-months and 4,984,405 person-months, respectively. Antipsychotic prescribing declined over the study period in both settings. After the launch of the Partnership, the rate of decline in antipsychotic prescribing slowed in AL residents with dementia (slope change = 0.03 [95% CLs: 0.02, 0.04]) while the rate of decline in antipsychotic prescribing increased in LSNH residents with dementia (slope change = -0.12 [95% CLs: -0.16, -0.08]). Antidepressants were the most prevalent medication prescribed, anticonvulsant/mood stabilizer prescribing increased, and anxiolytic/sedative-hypnotic and antidementia medication prescribing declined. CONCLUSIONS The federal Partnership to reduce antipsychotic prescribing in NH residents did not appear to affect antipsychotic prescribing in AL residents with dementia. Given the increase in the prescribing of mood stabilizers/anticonvulsants that occurred after the launch of the Partnership, monitoring may be warranted for all psychotropic medications in AL and NH settings.
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Development of instant vegetarian cream soup from tempeh powder to increase
antioxidant capacities. FOOD RESEARCH 2022. [DOI: 10.26656/fr.2017.6(4).635] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Tempeh is an Indonesian traditional soyfood made by Rhizopus spp. fermentation.
Tempeh has been well known as a vegetarian-friendly food and has been processed into
various derived food products. This study aimed to develop an instant vegetarian cream
soup from tempeh powder. The addition of tempeh powder was expected to increase the
product’s antioxidant activity without compromising its physicochemical properties as an
instant product. The five different formulations of cream soups containing 0–30% tempeh
powder were analysed for their physicochemical properties (dissolving time, density,
viscosity, colour, pH), antioxidant capacity (total phenolic content, total flavonoid content,
DPPH radical scavenging activity, reducing power, and ferrous ion chelating ability), and
hedonic test. Soup cream made with more tempeh power had a higher dissolving time, but
lower viscosity, lightness value, and pH value. However, their antioxidant activities also
increased with the increase of tempeh powder added. From the hedonic analysis, the
formulation with 15% tempeh powder showed the highest hedonic rate and therefore, was
chosen as the best formulation. In conclusion, the addition of tempeh powder did not only
give a better consumer acceptance but also higher antioxidant activities.
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Determinants of knowledge and perception of probiotic by Jabodetabek college students. FOOD RESEARCH 2020. [DOI: 10.26656/fr.2017.4(5).133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Beneficial effects provided by probiotic products may not necessarily influence the
perception of college students. This research was aimed to evaluate the relationship
among the college student’s knowledge, experience, perception, and purchase intension of
probiotics among the Jabodetabek (Jakarta, Bogor, Depok, Tangerang, Bekasi) college
students. The questionnaire responses from 200 participants with diverse demographic
backgrounds were collected. The results showed that the average score on the probiotic
knowledge and perception was good. According to chi-square test, there was no
correlation among all variables of demographic on probiotic knowledge and experience.
Furthermore, only respondent’s experience played a role in their perception of probiotics
(p value = 0.00) which was correlated to purchase intention indicated by p value = 0.00.
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Abstract
Background A community of practice (cop) is formally defined as a group of people who share a concern or a passion for something they do and who learn how to do it better as they interact regularly. Communities of practice represent a promising approach for improving cancer care outcomes. However, little research is available to guide the development of oncology cops. In 2015, our urban community hospital launched an oncology cop, with the goals of decreasing barriers to access, fostering collaboration, and improving practitioner knowledge of guidelines and services in cancer care. Here, we share insights from a qualitative analysis of feedback from participants in our cop. The objective of the project was to identify participant perspectives about preferred cop features, with a view to improving the quality of our community hospital's oncology cop. Methods After 5 in-person meetings of our oncology cop, participants were surveyed about what the cop should start, stop, and continue doing. Qualitative methods were used to analyze the feedback. Results The survey collected 250 comments from 117 unique cop participants, including family physicians, specialist physicians, nurses, and allied health care practitioners. Analysis identified participant perspectives about the key features of the cop and avenues for improvement across four themes: supporting knowledge exchange, identifying and addressing practice gaps, enhancing interprofessional collaboration, and fostering a culture of partnership. Conclusions Based on the results, we identified several considerations that could be helpful in improving our cop. Our findings might help guide the development of oncology cops at other institutions.
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Abstract
Background Communities of practice (cops) have been shown to be effective models for achieving quality outcomes in health care. Objective Here, we describe the application of the cop model to the Canadian oncology context. Methods We established an oncology cop at our urban community hospital and its networks. Goals were to decrease barriers to access, foster collaboration, and improve knowledge of guidelines in cancer care. We hosted 6 in-person multidisciplinary meetings, focusing on screening, diagnosis, and management of common solid tumours. Health care providers affiliated with our hospital were invited to attend and to complete post-meeting surveys. Likert scales assessed whether cop goals were realized. Results Meetings attracted a mean of 57 attendees (range: 48-65 attendees), with a mean of 84% completing the surveys and consenting to the analysis. Attendees included family physicians (mean: 41%), specialist physicians (mean: 24%), nurses (mean: 10%), and allied health care providers (mean: 22%). Repeat attendance increased during the series, with 85% of attendees at the final meeting having attended 1 or more prior meetings. Across the series, most participants agreed or strongly agreed that the cop reduced barriers (mean: 76.0% ± 7.9%) and improved access to cancer care services (mean: 82.4% ± 8.1%) and subject matter experts (mean: 91.7% ± 4.2%); fostered teamwork (mean: 84.5% ± 6.8%) and a culture of collaboration (mean: 94.8% ± 4.2%); improved knowledge of cancer care services (mean: 93.3% ± 4.8%), standards of practice (mean: 92.3% ± 3.1%), and quality indicators (mean: 77.5% ± 6.3%); and improved cancer-related practice (mean: 88.8% ± 4.6%) and satisfaction in caring for cancer patients (mean: 82.9% ± 6.8%). Participant feedback carried a potential for bias. Conclusions We demonstrated the feasibility of oncology cops and found that participants perceived their value in reducing barriers to access, fostering collaboration, and improving knowledge of guidelines in cancer care.
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P-032: Noninvasive prenatal detection of int22h -related inversions and point mutations in maternal plasma of hemophilia carriers by single molecule counting strategies. Thromb Res 2017. [DOI: 10.1016/s0049-3848(17)30130-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Abstract
Coupling between the lower and upper atmosphere, combined with loss of gas from the upper atmosphere to space, likely contributed to the thin, cold, dry atmosphere of modern Mars. To help understand ongoing ion loss to space, the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft made comprehensive measurements of the Mars upper atmosphere, ionosphere, and interactions with the Sun and solar wind during an interplanetary coronal mass ejection impact in March 2015. Responses include changes in the bow shock and magnetosheath, formation of widespread diffuse aurora, and enhancement of pick-up ions. Observations and models both show an enhancement in escape rate of ions to space during the event. Ion loss during solar events early in Mars history may have been a major contributor to the long-term evolution of the Mars atmosphere.
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Abstract
The Mars Atmosphere and Volatile Evolution (MAVEN) mission, during the second of its Deep Dip campaigns, made comprehensive measurements of martian thermosphere and ionosphere composition, structure, and variability at altitudes down to ~130 kilometers in the subsolar region. This altitude range contains the diffusively separated upper atmosphere just above the well-mixed atmosphere, the layer of peak extreme ultraviolet heating and primary reservoir for atmospheric escape. In situ measurements of the upper atmosphere reveal previously unmeasured populations of neutral and charged particles, the homopause altitude at approximately 130 kilometers, and an unexpected level of variability both on an orbit-to-orbit basis and within individual orbits. These observations help constrain volatile escape processes controlled by thermosphere and ionosphere structure and variability.
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Nucleostemin stabilizes ARF by inhibiting the ubiquitin ligase ULF. Oncogene 2014; 34:1688-97. [PMID: 24769896 PMCID: PMC4212020 DOI: 10.1038/onc.2014.103] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2013] [Revised: 02/02/2014] [Accepted: 03/13/2014] [Indexed: 12/18/2022]
Abstract
Up-regulated expression of nucleolar GTPase Nucleostemin (NS) has been associated with increased cellular proliferation potential and tumor malignancy during cancer development. Recent reports attribute the growth regulatory effects of NS protein to its role in facilitating ribosome production. However, the oncogenic potential of NS remains unclear since imbalanced levels of NS have been reported to exert growth inhibitory effect by modulating p53 tumor suppressor activity. It also remains in questions if aberrant NS levels might play a p53-independent role in regulation of cell proliferation and growth. In this study, we performed affinity purification and mass spectrometry analysis to explore protein-protein interactions influencing NS growth regulatory properties independently of p53 tumor suppressor. We identified the Alternative Reading Frame (ARF) protein as a key protein associating with NS and further verified the interaction through in vitro and in vivo assays. We demonstrated that NS is able to regulate cell cycle progression by regulating the stability of the ARF tumor suppressor. Furthermore, overexpression of NS suppressed ARF polyubiquitination by its E3 ligase ULF and elongated its half-life, while knockdown of NS led to the decrease of ARF levels. Also, we found that NS can enhance NPM stabilization of ARF. Thus, we propose that in the absence of p53, ARF can be stabilized by NS and NPM to serve as an alternative tumor suppressor surveillance, preventing potential cellular transformation resulting from the growth inducing effects of NS overexpression.
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Identification and Characterization of Neurocranial Skeletal Progenitor Cells. J Surg Res 2013. [DOI: 10.1016/j.jss.2012.10.856] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Abstract
Background Improving access to better, more efficient, and rapid cancer diagnosis is a necessary component of a high-quality cancer system. How diagnostic services ought to be organized, structured, and evaluated is less understood and studied. Our objective was to address this gap. Methods As a quality initiative of Cancer Care Ontario’s Program in Evidence-Based Care, the Diagnostic Assessment Standards Panel, with representation from clinical oncology experts, institutional and clinical administrative leaders, health service researchers, and methodologists, conducted a systematic review and a targeted environmental scan of the unpublished literature. Standards were developed based on expert consensus opinion informed by the identified evidence. Through external review, clinicians and administrators across Ontario were given the opportunity to provide feedback. Results The body of evidence consists of thirty-five published studies and fifteen unpublished guidance documents. The evidence and consensus opinion consistently favoured an organized, centralized system with multidisciplinary team membership as the optimal approach for the delivery of diagnostic cancer assessment services. Independent external stakeholders agreed (with higher mean values, maximum 5, indicating stronger agreement) that dap standards are needed (mean: 4.6), that standards should be formally approved (mean: 4.3), and importantly, that standards reflect an effective approach that will lead to quality improvements in the cancer system (mean: 4.5) and in patient care (mean: 4.3). Interpretation Based on the best available evidence, standards for the organization of daps are offered. There is clear need to integrate formal and comprehensive evaluation strategies with the implementation of the standards to advance this field.
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316: Successful Hemostasis In Normal and Anti-Coagulated Hosts Using QCI, a Kaolin-Based Hemostatic Agent. Ann Emerg Med 2010. [DOI: 10.1016/j.annemergmed.2010.06.366] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Development Of An In Vitro Test For Triatoma Specific IgE. J Allergy Clin Immunol 2010. [DOI: 10.1016/j.jaci.2009.12.788] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Superlinear dose dependence of high temperature thermoluminescence peaks in Al2O3:C. RADIATION PROTECTION DOSIMETRY 2006; 119:71-4. [PMID: 16644951 DOI: 10.1093/rpd/nci642] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
We report on strong superlinearity of high temperature (300-700 degrees C) thermoluminescence (TL) peaks in alpha-Al2O3:C powder. The main dosimetric peak at approximately 200 degrees C, previously found to exhibit slight superlinearity, is now shown to yield a slope of approximately 1.15 on a log(intensity) vs. log(dose) curve. Higher temperature peaks at approximately 320, 450 and 650 degrees C, previously reported following UV and X-ray excitation, have now been observed after beta irradiation and showed stronger superlinearity. Using a blue filter, the weak peak at approximately 320 degrees C started about quadratically and the slope on the log-log scale decreased gradually from 2 to about unity at approximately 100 Gy. The two higher temperature peaks at approximately 450 and approximately 650 degrees C also exhibited a strong superlinear dose dependence in this dose range, with an average slope of approximately 2. Roughly similar behaviour has been found when a UV filter was used. The possible explanation of the strong superlinearity is discussed.
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Abstract
The thermoluminescence (TL) intensity in different materials is usually a monotonic increasing function of the dose, which quite often reaches a saturation value. In several materials, however, non-monotonic dose dependence has been observed. The TL intensity reached a maximum at a certain dose and decreased at higher ones. Some authors refer to this effect as 'radiation damage'. In the present work, we show that the non-monotonic dependence can easily be demonstrated to result from competition between transitions model with two trapping states and two kinds of recombination centres. Two kinds of competition are considered. One in which competition during excitation dominates, the filling of the active luminescence centre is non-monotonic, and the resulting TL is non-monotonic. In the other, the filling of traps and centres is monotonically increasing, but the competition during heating causes TL intensity to reach a maximum and decline at higher doses.
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Location, identification, and size distribution of depleted uranium grains in reservoir sediments. JOURNAL OF ENVIRONMENTAL RADIOACTIVITY 2006; 89:240-8. [PMID: 16806609 DOI: 10.1016/j.jenvrad.2006.05.007] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/01/2005] [Revised: 05/01/2006] [Accepted: 05/17/2006] [Indexed: 05/10/2023]
Abstract
The location, nature, and size distribution of uranium-rich grains in sediment layers can be identified by sunbursts of etched particle tracks if each sample is pressed against a track detector, next irradiated with thermal neutrons, and the detectors then chemically etched to reveal fission tracks. The total track abundance from the sample is a measure of the 235U content; hence, if the bulk uranium (mostly 238U) has been measured, the two sets of results give the depletion or enrichment of the uranium. Sunbursts of tracks mark the locations of low-abundance, high-uranium grains allowing them to be singled out for further study.
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Masses cervicales récidivantes en rapport avec une maladie de kimura. J Neuroradiol 2005; 32:287-8. [PMID: 16237373 DOI: 10.1016/s0150-9861(05)83156-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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N-butyl 2-cyanoacrylate embolization of spinal dural arteriovenous fistulae: CT evaluation, technical features, and outcome prognosis in 26 cases. AJNR Am J Neuroradiol 2005; 26:929-35. [PMID: 15814948 PMCID: PMC7977144] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2023]
Abstract
BACKGROUND AND PURPOSE This study investigated the role of CT as an early predictor of outcome prognosis after glue embolization of spinal dural arteriovenous fistulas (SDAVF). METHODS Over a 13-year period, 26 patients underwent glue embolization of SDAVF and were retrospectively reviewed. Immediately after embolization, each patient had CT evaluation of cast position. Mean follow-up angiography was 23.4 months (range, 1-87 months; median, 21 months). Both MR images and clinical data (e.g., gait and micturition disabilities according to the Aminoff and Logue disability scale, deep and superficial sensitivity) were analyzed, with a mean follow-up of 37.7 months (range, 12-98 months; median, 28 months). Data were tested by univariate analysis by using Fisher's exact test and the Kruskall Wallis test, depending on the order of the qualitative variables. RESULTS Glue was found in the dura mater on CT in 19 (73%) patients. None of these patients had a recanalized fistula on angiography, and the clinical status of all of them improved. Glue was observed in or proximal to the foramen on CT in seven (27%) patients. In five of them, the fistula was recanalized within a mean period of 9 months (range, 3-24 months; median, 6 months) and their clinical status worsened. All five required surgical treatment. On angiography, the absence of fistula recanalization was observed in 21 (81%) patients and correlated with improvements in gait (P = .016), sensitivity (P = .030), and micturition (P = .080). It also correlated with a decrease in the extent of the abnormally high intramedullary T2 signal intensity (P = .002), a decrease in spinal cord diameter (P = .017), and the resolution of prominent perimedullary vessels (P < .001). The presence of glue within the dura mater on CT correlated with the absence of fistula recanalization (P = .045) and with overall improvement in clinical status, including gait and/or sensitivity and/or micturition (P = .042). CONCLUSION CT evaluation of embolization cast position immediately after embolization may constitute an early and reliable tool for predicting permanent fistula occlusion and the prognosis for outcome.
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Thermoluminescence response of K2YF5:Tb3+ crystals to photon radiation fields. RADIATION PROTECTION DOSIMETRY 2004; 112:435-438. [PMID: 15466918 DOI: 10.1093/rpd/nch406] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
This investigation has been performed to test the feasibility of using K2YF5:Tb3+ crystals as thermoluminescence dosemeters (TLD). K2YF5 single crystals doped with 0.2, 10.0 and 50.0 at.% of trivalent optically active Tb3+ ions as well as K2TbF5 and undoped K2YF5 crystals have been synthesized under hydrothermal conditions. Polished crystal platelets with thickness of about 1 mm have been irradiated with X and gamma rays in order to study thermoluminescent (TL) sensitivity as well as dose and energy response in terms of the Tb3+ concentration in K2YF5. Within this concentration series, K2YF5 crystals doped with 10.0 at.% Tb3+ have been found to have maximum TL response due to a broad asymmetric TL glow peak at 269 degrees C with good linearity of dose response and reproducibility of dose measurements. After deconvolution, the main dosimetric peak has been revealed to be composed of two individual peaks, both with linear TL response behaviour, centered at 210 and 269 degrees C. As it has been proved, the linear TL signal coefficient for K2Y0.9Tb0.1F5 is almost 10 times greater than that for commercial TLD-100 (LiF:Mg,Ti), irradiated with a 137Cs gamma radiation source at the same conditions. The reported results indicate that K2YF5 crystals doped with Tb3+ have potential as promising materials for radiation dosemeters.
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Endovascular management of carotid-cavernous fistula combined with ipsilateral internal carotid artery occlusion due to gunshot: contra-lateral arterial approach. Acta Neurochir (Wien) 2004; 146:403-6; discussion 406. [PMID: 15057536 DOI: 10.1007/s00701-004-0232-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
Abstract
We hereby report the endovascular management of a posttraumatic caroticocavernous fistula combined with an occlusive ipsilateral carotid dissection; this was successfully managed by a contra-lateral arterial approach via the anterior communicating artery.
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Abstract
Using an automated PCR-based genomics approach, TOtal Gene expression Analysis (TOGA), we have examined gene expression profiles of mouse striatum and frontal cortex in response to clozapine and haloperidol drug treatment. Of 17 315 mRNAs observed, TOGA identified several groups of related molecules that were regulated by drug treatment. The expression of some genes encoding proteins involved in neurotransmission, signal transduction, oxidative stress, cell adhesion, apoptosis and proteolysis were altered in the brains of both clozapine- and haloperidol-treated mice as recognized by TOGA. Most notable was the differential expression of those genes whose products are associated with lipid metabolism. These include apolipoprotein D (apoD), the mouse homolog of oxysterol-binding protein-like protein 8 (OSBPL8), a diacylglycerol receptor (n-chimerin), and lysophosphatidic acid (LPA) acyltransferase. Real-time PCR analysis confirmed increases in the RNA expression of apoD (1.6-2.2-fold) and OSBPL8 (1.7-2.6-fold), and decreases in the RNA expression of n-chimerin (1.5-2.2-fold) and LPA acyltransferase (1.5-fold) in response to haloperidol and/or clozapine treatment. Additional molecules related to calcium homeostasis and signal transduction, as well as four sequences of previously unidentified mRNAs, were also confirmed by real-time PCR to be regulated by drug treatment. While antipsychotic drugs may affect several metabolic pathways, lipid metabolism/signaling pathways may be of particular importance in the mechanisms of antipsychotic drug action and in the pathophysiology of psychiatric disorders.
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Acute basilar artery occlusion treated by thromboaspiration in a cocaine and ecstasy abuser. Neurology 2003; 61:839-41. [PMID: 14504335 DOI: 10.1212/wnl.61.6.839] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Thromboaspiration was performed in a young adult in a coma because of acute basilar artery occlusion associated with cocaine and ecstasy abuse 30 hours after symptom onset. There was complete recanalization of the basilar artery and favorable recovery. Because cocaine and ecstasy abuse has been reported to be a risk factor for ischemic stroke and fatal brain hemorrhage, thromboaspiration may be an alternative therapy to thrombolysis.
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Exposure apportionment: ranking food items by their contribution to dietary exposure. JOURNAL OF EXPOSURE ANALYSIS AND ENVIRONMENTAL EPIDEMIOLOGY 2002; 12:233-43. [PMID: 12087429 DOI: 10.1038/sj.jea.7500230] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2002] [Indexed: 04/18/2023]
Abstract
This paper identifies and ranks food items by estimating their contribution to the dietary exposure of the US population and 19 subpopulation groups. Contributions to dietary exposures to arsenic, cadmium, chromium, lead, nickel, benzene, chlorpyrifos, and diazinon are estimated using either the Dietary Exposure Potential Model (DEPM) approach, the National Human Exposure Assessment Survey Arizona (NHEXAS-AZ) approach or the combination of the two. The DEPM is a computer model that uses several national databases of food consumption and residue concentrations for estimating dietary. The DEPM approach ranks the contribution of food items to the total dietary exposure using two methods, the direct method that ranks contributions by population exposure magnitude and the weighted method that ranks by subpopulation exposure magnitude. The DEPM approach identifies highly exposed subpopulations and a relatively small number of food items contributing the most to dietary exposure. The NHEXAS-AZ approach uses the NHEXAS-AZ database containing food consumption data for each subject and chemical residues of a composite of food items consumed by each subject in 1 day during the sampling week. These data are then modeled to obtain estimates of dietary exposure to chemical residues. The third approach uses the NHEXAS-AZ consumption data with residue values from the national residue database. This approach also estimates percent contributions to exposure of each ranked food item for the Arizona population. Dietary exposures estimated using the three approaches are compared. The DEPM results indicate groups with highest dietary exposures include Nonnursing Infants, Children 1-6, Hispanic, Non-Hispanic White, Western, Northeast and Poverty 0-130%. The use of the Combined National Residue Database (CNRD) identifies 43 food items as primary contributors to total dietary exposure; they contribute a minimum of 68% of the total dietary exposure to each of the eight chemical residues. The percent contribution of ranked food items estimated using the NHEXAS samples is smaller than those obtained from the western US population via the DEPM. This indicates differences in consumption characteristics of the two groups with respect to the ranked food items. Six of 15 food items consumed by the NHEXAS-AZ subjects per day are ranked food items contributing between 56% and 70% of the estimated NHEXAS-AZ dietary exposure to each of the eight chemical residues. The difference between total dietary exposure estimates from the DEPM and NHEXAS-AZ approaches varies by chemical residue and is attributable to differences in sampling and analytical methods, and geographic areas represented by the data. Most metal exposures estimated using the NHEXAS consumption data with the CNRD have lower values than those estimated via the other approaches, possibly because the NHEXAS-AZ residue values are higher than the CNRD values. In addition, exposure estimates are seemingly affected by the difference in demographic characteristics and factors that affect types and amounts of food consumed. Efficient control strategies for reducing dietary exposure to chemical residues may be designed by focusing on the relatively small number of food items having similar ingredients that contribute substantively to the total ingestion exposure.
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Nondestructive in situ thermoluminescence using CO(2) laser heating. OPTICS EXPRESS 2002; 10:291-296. [PMID: 19436359 DOI: 10.1364/oe.10.000291] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have obtained thermoluminescence glow curves nondestructively from large, solid, ceramic samples by laser spot heating. Although the samples are brittle, laser thermoluminescence glow curves could be obtained with no visible damage to the samples. The experimental glow curves match with theory. By contrast, conventional thermoluminescence measurements require small samples to be removed from a ceramic and placed in a thermoluminescence machine. Laser-induced thermoluminescence glow curves from LiF, silica, and porcelain are presented.
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Abstract
The main arterial supply of the dorso-lumbar spinal cord is usually derived from a single anterior radiculo-medullary artery called the artery of Adamkiewicz and referred to as having a middle or low location. In some cases, the artery origin is higher, and a vessel which arises in the lower part of the region supplements the supply of the anterior spinal artery. In the literature, those arteries have been described as arising from L3 upwards, and have never been previously described angiographically, to our knowledge, below this level, although Suh and Alexander and Gililan have mentioned this eventuality. Of the 4,000 spinal cord angiographies performed in our institution, we report three cases in which the fourth lumbar artery flows into the anterior spinal artery of the conus medullaris. This anatomical variant may explain the sometimes devastating post-operative neurological complications from a spinal cord infarction on surgery of the lumbar spine or the abdominal aorta below L3.
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Mapping genes regulating lymphocyte function: correlations with autoimmunity? CURRENT DIRECTIONS IN AUTOIMMUNITY 2002; 1:226-46. [PMID: 11791444 DOI: 10.1159/000060489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
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A ligand for the chemokine receptor CCR7 can influence the homeostatic proliferation of CD4 T cells and progression of autoimmunity. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:6724-30. [PMID: 11739486 DOI: 10.4049/jimmunol.167.12.6724] [Citation(s) in RCA: 81] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Homeostasis of T cell numbers in the periphery implies an ability of lymphocytes to sense cell numbers. Although the mechanisms are unknown, we find that the chemokine CCL21 (also known as TCA4, SLC, 6Ckine), a ligand for the chemokine receptor CCR7, can regulate homeostasis of CD4 (but not CD8) T cells. In the absence of CCR7 ligands, transferred CD4 T cells failed to expand in lymphopenic hosts, whereas in the presence of CCL21 overexpression, homeostatic CD4 T cell proliferation occurred even in nonlymphopenic recipients. Ag-specific CD4 T cells transferred into Ag-expressing mice proliferated and induced autoimmunity only in lymphopenic recipients. Pancreatic expression of CCL21 was sufficient to replace the requirement for lymphopenia in the progression of autoimmune disease. These results suggest that CD4 T cells use local concentrations of CCR7 ligands as an index of T cell steady state numbers and that homeostatic expansion of the T cell population may be a contributing factor in the development of autoimmune disease.
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Abstract
With the availability of new technologies for analysis of gene expression, drug targets may now be identified through more focused rational approaches. We have developed an extremely sensitive, reproducible, and accurate method called TOGA, enabling analysis of nearly all genes within an RNA sample. This technology can be used to identify genes regulated in a great variety of situations. For example, we have been able to find genes with expression restricted to specific brain regions, and in a recent example, we found a gene regulated in specific brain regions in response to clozapine treatment. These studies will quickly lead to identification of genes critical to specific biological and clinical processes, accelerating the development of new targets and therapies.
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Defective CD8+ T cell peripheral tolerance in nonobese diabetic mice. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2001; 167:1112-7. [PMID: 11441123 DOI: 10.4049/jimmunol.167.2.1112] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Nonobese diabetic (NOD) mice develop spontaneous autoimmune diabetes that involves participation of both CD4+ and CD8+ T cells. Previous studies have demonstrated spontaneous reactivity to self-Ags within the CD4+ T cell compartment in this strain. Whether CD8+ T cells in NOD mice achieve and maintain tolerance to self-Ags has not previously been evaluated. To investigate this issue, we have assessed the extent of tolerance to a model pancreatic Ag, the hemagglutinin (HA) molecule of influenza virus, that is transgenically expressed by pancreatic islet beta cells in InsHA mice. Previous studies have demonstrated that BALB/c and B10.D2 mice that express this transgene exhibit tolerance of HA and retain only low-avidity CD8+ T cells specific for the dominant peptide epitope of HA. In this study, we present data that demonstrate a deficiency in peripheral tolerance within the CD8+ T cell repertoire of NOD-InsHA mice. CD8+ T cells can be obtained from NOD-InsHA mice that exhibit high avidity for HA, as measured by tetramer (K(d)HA) binding and dose titration analysis. Significantly, these autoreactive CD8+ T cells can cause diabetes very rapidly upon adoptive transfer into NOD-InsHA recipient mice. The data presented demonstrate a retention in the repertoire of CD8+ T cells with high avidity for islet Ags that could contribute to autoimmune diabetes in NOD mice.
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MESH Headings
- Adoptive Transfer
- Animals
- Autoantigens/metabolism
- CD8-Positive T-Lymphocytes/immunology
- CD8-Positive T-Lymphocytes/virology
- Diabetes Mellitus, Type 1/genetics
- Diabetes Mellitus, Type 1/immunology
- Epitopes, T-Lymphocyte/genetics
- Epitopes, T-Lymphocyte/immunology
- Hemagglutinin Glycoproteins, Influenza Virus/genetics
- Hemagglutinin Glycoproteins, Influenza Virus/immunology
- Hemagglutinin Glycoproteins, Influenza Virus/metabolism
- Immune Tolerance/genetics
- Influenza A virus/immunology
- Lymphocyte Activation/genetics
- Mice
- Mice, Inbred BALB C
- Mice, Inbred NOD/genetics
- Mice, Inbred NOD/immunology
- Mice, Transgenic
- Protein Binding/genetics
- Protein Binding/immunology
- Radiation Chimera/immunology
- T-Lymphocytes, Cytotoxic/transplantation
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Nasopharyngeal carcinoma heterogeneity of DNA content identified on cytologic preparations. ANALYTICAL AND QUANTITATIVE CYTOLOGY AND HISTOLOGY 2001; 23:213-7. [PMID: 11444191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/20/2023]
Abstract
OBJECTIVE To evaluate tumor heterogeneity of DNA content in nasopharyngeal carcinoma (NPC) performed on cytologic specimens. STUDY DESIGN Image cytometric analysis of DNA ploidy status of 40 NPCs was performed on nasopharyngeal brushing smears stained with the Feulgen method after hematoxylin eosin staining. If the DNA distribution pattern from the same tumor exhibited diploid, aneuploid or/and tetraploid peaks or some combination of these patterns, the presence of tumor heterogeneity of DNA content was identified. RESULTS Thirty-four cases (85%) had a nondiploid DNA pattern among the 40 NPCs. Twenty-eight cases exhibited tumor heterogeneity of DNA content (70%). Of the 28 tumors, 13 (46%) had a combination of diploid and tetraploid patterns, 10 (37%) had a combination of diploid and aneuploid patterns, 3 cases (11%) had a combination of tetraploid and aneuploid patterns, and 2 cases had two aneuploid stem lines. The relationship between DNA ploidy pattern and tumor histologic and cytologic morphology was also examined. CONCLUSION There is a high incidence of DNA content heterogeneity in NPC. The relevance of tumor heterogeneity to the biologic behavior of NPC awaits further study. DNA quantification with image cytometry on destained cytologic preparations is feasible and reliable.
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Abstract
Autoimmune diabetes is associated with T helper 1 polarization, but protection from disease can be provided by the application of T helper 2 (Th2) cytokines. To test whether genetic manipulation of T-cells can provide protective Th2 responses, we developed transgenic mice in which T-cells express the interleukin-4-specific transcription factor c-Maf. When crossed with a transgenic model that combines a class II restricted T-cell receptor specific for influenza hemagglutinin with islet beta-cell expression of hemagglutinin, the c-Maf transgene provided significant protection from spontaneous autoimmunity but not from adoptively transferred diabetes. In a second transgenic model in which islet cells express the lymphocytic choriomeningitis virus nucleoprotein, the virus infection triggers autoimmune diabetes within a few weeks involving both CD4 and CD8 T-cells; here too transgenic c-Maf provided significant protection. Surprisingly, when the c-Maf transgene was backcrossed with the NOD model of spontaneous disease, no protection was evident. Thus, transgenic c-Maf can strongly influence autoimmune disease development in some models, but additional factors, such as background genetic differences, can influence the potency of its effect.
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Abstract
Susceptibility and resistance to autoimmune diabetes appear to be regulated at several levels. Whereas the effector functions of autoimmunity are dependent on the antigen-specific responses of autoreactive T cells, the development of tissue-specific autoimmunity appears to be additionally dependent on tissue-specific factors. Thus, the recruitment of T lymphocytes into the vicinity of islet tissue is driven by the local production of chemokines with a pattern unique to islet tissue. The accumulation of lymphocytes triggers events that lead to the local development of new lymphoid tissue, enhancing the presentation of islet-specific antigens to the immune system. In the presence of additional genetic factors allowing persistent immune responses, autoreactivity is permitted to progress until end-stage autoimmune diabetes develops. My laboratory is studying the influence of tissue-specific factors and the genetic regulation of lymphocyte reactivity. An integrated understanding of these effects should lead to a more physiologic approach to prevention and treatment of autoimmune diabetes.
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Endemic melioidosis in tropical northern Australia: a 10-year prospective study and review of the literature. Clin Infect Dis 2000; 31:981-6. [PMID: 11049780 DOI: 10.1086/318116] [Citation(s) in RCA: 353] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2000] [Revised: 03/21/2000] [Indexed: 11/03/2022] Open
Abstract
In a prospective study of melioidosis in northern Australia, 252 cases were found over 10 years. Of these, 46% were bacteremic, and 49 (19%) patients died. Despite administration of ceftazidime or carbapenems, mortality was 86% (43 of 50 patients) among those with septic shock. Pneumonia accounted for 127 presentations (50%) and genitourinary infections for 37 (15%), with 35 men (18%) having prostatic abscesses. Other presentations included skin abscesses (32 patients; 13%), osteomyelitis and/or septic arthritis (9; 4%), soft tissue abscesses (10; 4%), and encephalomyelitis (10; 4%). Risk factors included diabetes (37%), excessive alcohol intake (39%), chronic lung disease (27%), chronic renal disease (10%), and consumption of kava (8%). Only 1 death occurred among the 51 patients (20%) with no risk factors (relative risk, 0.08; 95% confidence interval, 0.01-0.58). Intensive therapy with ceftazidime or carbapenems, followed by at least 3 months of eradication therapy with trimethoprim-sulfamethoxazole, was associated with decreased mortality. Strategies are needed to decrease the high mortality with melioidosis septic shock. Preliminary data on granulocyte colony-stimulating factor therapy are very encouraging.
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Abstract
Dye-doped solgel silica lasers with distributed feedback were demonstrated. Solgel silica slabs doped with Rhodamine 6G or Coumarin 460 dyes were fabricated. Periodic gain modulation in dye-doped solgel silica slabs were created by the interference pattern of the pumped laser beams diffracted by a holographic grating. Laser pulse trains with subnanosecond spikes were induced. Laser emission wavelengths were centered at 480 and 585 nm for Rhodamine 6G and Coumarin 460, respectively. It was possible for us to tune approximately 20 nm around the emission centers by varying the intersection angle. The laser linewidth was of the order of 60 pm.
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Cutting edge: ectopic expression of the chemokine TCA4/SLC is sufficient to trigger lymphoid neogenesis. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:3955-9. [PMID: 10754285 DOI: 10.4049/jimmunol.164.8.3955] [Citation(s) in RCA: 138] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
To test whether accumulation of naive lymphocytes is sufficient to trigger lymphoid development, we generated mice with islet expression of the chemokine TCA4/SLC. This chemokine is specific for naive lymphocytes and mature dendritic cells (DC) which express the CCR7 receptor. Islets initially developed accumulations of T cells with DC, with scattered B cells at the perimeter. These infiltrates consolidated into organized lymphoid tissue, with high endothelial venules and stromal reticulum. Infiltrate lymphocytes showed a naive CD44low CD25- CD69- phenotype, though half were CD62L negative. When backcrossed to RAG-1 knockout, DC were not recruited. Interestingly, islet lymphoid tissue developed in backcrosses to Ikaros knockout mice despite the absence of normal peripheral nodes. Our results indicate that TCA4/SLC can induce the development and organization of lymphoid tissue through diffential recruitment of T and B lymphocytes and secondary effects on stromal cell development.
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Abstract
The transcriptional coactivator p300 is essential for normal embryonic development and cellular differentiation. We have been studying the role of p300 in the transcription of a variety of genes, and we became interested in the role of this coactivator in the transcription of genes important in breast epithelial cell biology. From MCF-10A cells (spontaneously immortalized, nontransformed human breast epithelial cells), we developed cell lines that stably overexpress p300. These p300-overexpressing cells displayed reduced adhesion to culture dishes and were found to secrete an extracellular matrix deficient in laminin-5. Laminin-5 is the major extracellular matrix component produced by breast epithelium. Immunofluorescence studies, as well as experiments using normal matrix, confirmed that the decreased adhesion of p300-overexpressing cells is due to laminin-5-deficient extracellular matrix and not due to loss of laminin-5 receptors. Northern blots revealed markedly decreased levels of expression of two of the genes (designated LAMA3 and LAMC2) encoding the alpha3 and gamma2 chains of the laminin-5 heterotrimer in the cells that overexpress p300, whereas LAMB3 mRNA, encoding the third or beta3 chain of laminin-5, was not markedly reduced. Transient transfection experiments with a vector containing a murine LAMA3 promoter demonstrate that overexpressing p300 down-regulates the LAMA3 promoter. In summary, overexpression of p300 leads to down-regulation of laminin-5 production in breast epithelial cells, resulting in decreased adhesion.
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Fiber optic oxygen sensor based on phosphorescence quenching of erythrosin B trapped in silica-gel glasses. Anal Chim Acta 2000. [DOI: 10.1016/s0003-2670(99)00849-1] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Transgenic expression of Ly-49A in thymocytes alters repertoire selection. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2000; 164:884-92. [PMID: 10623836 DOI: 10.4049/jimmunol.164.2.884] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
A T cell-specific Ly-49A transgene inhibits TCR-mediated activation in the presence of H-2Dd. Expression of this transgene by developing thymocytes impairs negative selection evidenced by a failure to delete potentially autoreactive T cells and development of a graft-vs-host-disease-like syndrome. In mice carrying both the Ly-49A and a class II-restricted TCR transgene, positive selection was lost, but only when H-2Dd was present on thymic epithelium. These results are consistent with models suggesting that thymic selection is dependent on the perceived intensity of TCR signaling. More interestingly, these results show that Ly-49A does not simply provide a strict on/off switch for T cell responses. Since Ly-49A may shift the signaling threshold of TCR-induced triggering, inducible expression of Ly-49A may regulate peripheral memory/activated T cells by raising the threshold for T cell reactivation.
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Ability of a nondepleting anti-CD4 antibody to inhibit Th2 responses and allergic lung inflammation is independent of coreceptor function. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 163:6557-66. [PMID: 10586049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Nondepleting anti-CD4 Abs have been used in vivo to induce Ag-specific immunological tolerance in Th1 responses, including tissue allograft rejection and autoimmune diabetes. To examine whether this Ab (YTS177.9) acts by provoking a Th2 shift, we tested the effect in a mouse model of allergic lung inflammation. Interestingly, nondepleting anti-CD4 treatment induces tolerance to allergens as well, especially when given during initial priming. In vitro studies indicate that the effect of the Ab is independent of CD4 coreceptor function, as Ab treatment also inhibits proliferation and induces a persistent anergy in naive CD4 T cells stimulated by anti-CD3/CD28. Moreover, the Ab stimulated a distinct pattern of tyrosine phosphorylation in T cells even in the absence of TCR triggering, suggesting that signaling through CD4 alone induces significant physiological changes in T cell function. These results show that tolerance induced by anti-CD4 triggering is not a simple shift in Th1/Th2 effector function or depletion of Ag-specific cells, but may instead induce a persistent clonal anergy capable of blocking subsequent immunity.
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MESH Headings
- Administration, Intranasal
- Animals
- Antibodies, Monoclonal/administration & dosage
- Antibodies, Monoclonal/pharmacology
- CD4 Antigens/immunology
- CD4-Positive T-Lymphocytes/immunology
- CD4-Positive T-Lymphocytes/metabolism
- CD4-Positive T-Lymphocytes/pathology
- Clonal Anergy
- Epitopes, T-Lymphocyte/administration & dosage
- Epitopes, T-Lymphocyte/immunology
- Immunosuppressive Agents/administration & dosage
- Immunosuppressive Agents/pharmacology
- Inflammation/immunology
- Inflammation/prevention & control
- Intracellular Fluid/immunology
- Intracellular Fluid/metabolism
- Lung/immunology
- Lung/pathology
- Lymphocyte Depletion
- Mice
- Mice, Inbred BALB C
- Mice, Inbred C57BL
- Mice, Transgenic
- Ovalbumin/administration & dosage
- Ovalbumin/immunology
- Phosphorylation
- Receptors, Antigen, T-Cell/physiology
- Respiratory Hypersensitivity/immunology
- Respiratory Hypersensitivity/pathology
- Respiratory Hypersensitivity/prevention & control
- Th2 Cells/immunology
- Th2 Cells/metabolism
- Tyrosine/metabolism
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Influence of lymphocytes on the presence and organization of dendritic cell subsets in the spleen. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 1999; 163:4894-900. [PMID: 10528191] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Subscribe] [Scholar Register] [Indexed: 02/14/2023]
Abstract
Studies were undertaken to clarify the roles of individual leukocyte populations in maintaining the presence and organization of splenic dendritic cells (DCs). Using Abs specific for DC subsets, we found that the distinct types of DC maintained appropriate compartmentalization within the white pulp of lymphocyte-deficient mice despite an unusual overall distribution of DCs. Even in mice lacking both B and T lymphocytes, the central arteriole remained the structure around which T area DCs were organized. Marginal zone area DCs remained in a peripheral sheath excluded from the T area DCs. Additionally, we revealed an important role for splenic B cells in the presence and organization of marginal zone cells. B-deficient or B- and T-deficient mice lacked sialoadhesin+ marginal zone macrophages and lacked MAdCAM-1 expression in marginal zone reticular endothelial cells. Adoptive transfer of B lymphocytes induced MAdCAM-1 expression but failed to recruit marginal zone macrophages. Taken together, our results demonstrate that the arrival, localization, and persistence of DCs in spleen are events not solely dependent upon signals from the mature B and T cells or marginal zone macrophages. We suggest that specific stromal elements in the vicinity of the central arteriole are primarily responsible for providing directional cues to the DC.
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RelB modulation of IkappaBalpha stability as a mechanism of transcription suppression of interleukin-1alpha (IL-1alpha), IL-1beta, and tumor necrosis factor alpha in fibroblasts. Mol Cell Biol 1999; 19:7688-96. [PMID: 10523657 PMCID: PMC84809 DOI: 10.1128/mcb.19.11.7688] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Members of the NF-kappaB/RelB family of transcription factors play important roles in the regulation of inflammatory and immune responses. RelB, a member of this family, has been characterized as a transcription activator and is involved in the constitutive NF-kappaB activity in lymphoid tissues. However, in a previous study we observed an overexpression of chemokines in RelB-deficient fibroblasts. Here we show that RelB is an important transcription suppressor in fibroblasts which limits the expression of proinflammatory mediators and may exert its function by modulating the stability of IkappaBalpha protein. Fibroblasts from relb(-/-) mice overexpress interleukin-1alpha (IL-1alpha), IL-1beta, and tumor necrosis factor alpha in response to lipopolysaccharide (LPS) stimulation. These cells have an augmented and prolonged LPS-inducible IKK activity and an accelerated degradation which results in a diminished level of IkappaBalpha protein, despite an upregulated IkappaBalpha mRNA expression. Consequently, NF-kappaB activity was augmented and postinduction repression of NF-kappaB activity was impaired in these cells. The increased kappaB-binding activity and cytokine overexpression was suppressed by introducing RelB cDNA or a dominant negative IkappaBalpha into relb(-/-) fibroblasts. Our findings suggest a novel transcription suppression function of RelB in fibroblasts.
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49
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Abstract
In a number of animal models of spontaneous autoimmune diabetes, pathogenesis has been highly correlated with autoreactive T-cell production of the type 1 cytokine interferon-gamma (IFN-gamma), while protection from disease was associated with type 2 cytokines such as interleukin (IL)-4. Curiously, in some models, diabetes is associated with unexpected cytokine patterns; for example, diabetes can develop in NOD mice lacking a functional IFN-gamma gene. In another situation, acceleration of diabetes occurs in transgenic mice with constitutive beta-cell expression of the type 2 cytokine IL-10. IL-10 has generally been associated with immunosuppression, including the modulation of class II expression on antigen-presenting cells and the generation of regulatory CD4 T-cells. Because it is possible that unregulated expression of any cytokine might lead to unphysiological effects in vivo, we tested the notion that an inducible T-cell-specific IL-10 transgene might yet mediate a more physiological protection from autoimmune diabetes. Our results show that indeed, regulated T-cell production of IL-10 does not accelerate diabetes and instead can provide significant protection from disease. These results help rectify the apparent discrepancies between the effect of IL-10 on various models of autoimmune diabetes.
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Abstract
The establishment of CD4(+) T cell tolerance requires that self-reactive thymocytes are negatively selected during thymic development. A threshold of antigen concentration appears to exist for both MHC class I- and class II-mediated negative selection, below which clonal deletion of a self-reactive transgenic TCR does not occur. Similarly, both the specificity and thymic concentration of MHC molecules affect the efficiency with which autoreactive thymocytes are deleted. However, this threshold for MHC class II concentration has not been well established. Here, we show that this threshold must be extraordinarily low. We have used the human lysozyme promoter to re-express an A(beta)(b) cDNA on macrophages and other phagocytic myelomonocytic cells of class II-deficient A(beta)(b) -/- mice. Surface expression of I-A(b) could be detected on mature peritoneal macrophages and, minimally, on thymic dendritic cells; however, this level of expression was not sufficient for antigen-specific T cell activation. Nevertheless, when backcrossed onto an autoreactive K14 background, this minimal level of class II was sufficient to induce negative selection of a polyclonal self-reactive population. We conclude that provision of extremely low levels of class II to thymic dendritic cells confers on them the ability to mediate clonal deletion of autoreactive T cells.
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