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73.
Association of a Common Genetic Factor,PTGER3, With Outcome of Periodontal Therapy and Preterm Birth
Marjorie K. Jeffcoat Robert L. Jeffcoat Nipul Tanna Samuel H. Parry 《Journal of periodontology》2014,85(3):446-454
Background: Clinical evidence suggests an association between preterm birth and periodontal disease. This study explores whether specific genetic polymorphisms are associated with success of periodontal therapy in pregnant women with periodontal disease and, further, whether any of these same polymorphisms are also associated with spontaneous preterm birth (sPTB). Methods: One hundred sixty high‐risk pregnant women (6 to 20 weeks of gestation) with periodontal disease (≥3 sites with attachment loss ≥4 mm) were studied. All women received scaling and root planing plus oral hygiene instruction. Periodontal examinations were performed before treatment and 20 weeks later. Participants were classified according to two study outcomes: 1) success or failure of periodontal treatment; and 2) presence or absence of sPTB. Maternal DNA samples from mucosal swabs were characterized using a 1536‐SNP (single‐nucleotide polymorphism) custom polymerase chain reaction chip. A probabilistic model of each dichotomous outcome, derived using a stepwise Bayesian procedure, was compared to respective null hypotheses on the basis of Monte Carlo simulations and significance estimates obtained using three measures (z‐test, Welch t‐test, and probability convolution). The models were further confirmed by logistic regression analyses. Results: The models revealed a significant relation between a specific polymorphism of prostaglandin E receptor 3 (a gene associated with inflammatory response) and both periodontal treatment failure (odds ratio 11.09, P <0.0002) and sPTB (odds ratio 6.89, P <0.0032). Conclusions: These results demonstrate that the risk of unsuccessful periodontal treatment is associated with tag SNPs in specific genes that regulate the inflammatory response, one of which is also associated with sPTB. 相似文献
74.
Kuenyoul Park Min Kyu Kim Taegeun Lee Jinyoung Hong Hyun-Ki Kim Sunyoung Ahn Young-Jae Lee Jisun Kim Shin-Wha Lee Jong Won Lee Woochang Lee Sail Chun Byung Ho Son Kyung Hae Jung Yong-Man Kim Won-Ki Min Sei-Hyun Ahn 《Journal of clinical laboratory analysis》2020,34(12):e23524
BackgroundAs next‐generation sequencing (NGS) technology matures, various amplicon‐based NGS tests for BRCA1/2 genotyping have been introduced. This study was designed to evaluate an NGS test using a newly released amplicon‐based panel, AmpliSeq for Illumina BRCA Panel (AmpliSeq panel), for detection of clinically significant BRCA variants, and to compare it to another amplicon‐based NGS test confirmed by Sanger sequencing.MethodsWe reviewed BRCA test results done by NGS using the TruSeq Custom Amplicon kit from patients suspected of hereditary breast/ovarian cancer syndrome (HBOC) in 2018. Of those, 96 residual samples with 100 clinically significant variants were included in this study using predefined criteria: 100 variants were distributed throughout the BRCA1 and BRCA2 genes. All target variants were confirmed by Sanger sequencing. Duplicate NGS testing of these samples was performed using the AmpliSeq panel, and the concordance of results from the two amplicon‐based NGS tests was assessed.ResultsNinety‐nine of 100 variants were detected in duplicate BRCA1/2 genotyping using the AmpliSeq panel (sensitivity, 99%; specificity, 100%). In the discordant case, one variant (BRCA1 c.3627dupA) was found only in repeat 1, but not in repeat 2. Automated nomenclature of all variants, except for two indel variants, was in consensus with Human Genome Variation Society nomenclature.ConclusionOur findings confirm that the analytic performance of the AmpliSeq panel is satisfactory, with high sensitivity and specificity. 相似文献
75.
Stephen A. Wonderlich Donald Fullerton William J. Swift Marjorie H. Klein 《The International journal of eating disorders》1994,15(3):233-243
In order to assess the relationship of personality disorder and eating disorder outcome 30 eating disordered patients were followed up 4–5 years after taking part in a study examining the prevalence of personality disorders in eating disordered individuals. Subjects with personality disorders did not differ from those without personality disorders in the amount of symptomatic change over time, although their psychopathology generally remained more severe. The relationship of personality disorder and clinical outcome ratings varied depending on the personality measure. SCID-II personality disorder diagnoses were not significantly associated with outcome ratings, but were related to a greater likelihood to be hospitalized and treated with psychotropic medications. Results with a new personality measure, the Wisconsin Personality Inventory, did display an association between personality disturbance and eating disorder outcome ratings and also suggested that borderline personality was a significant predictor of outcome. © 1994 by John Wiley & Sons, Inc. 相似文献
76.
Marjorie Damian Sophie Mary Mathieu Maingot Céline M'Kadmi Didier Gagne Jean-Philippe Leyris Séverine Denoyelle Gérald Gaibelet Laurent Gavara Mauricio Garcia de Souza Costa David Perahia Eric Trinquet Bernard Mouillac Ségolène Galandrin Céline Galès Jean-Alain Fehrentz Nicolas Floquet Jean Martinez Jacky Marie Jean-Louis Banères 《Proceedings of the National Academy of Sciences of the United States of America》2015,112(5):1601-1606
How G protein-coupled receptor conformational dynamics control G protein coupling to trigger signaling is a key but still open question. We addressed this question with a model system composed of the purified ghrelin receptor assembled into lipid discs. Combining receptor labeling through genetic incorporation of unnatural amino acids, lanthanide resonance energy transfer, and normal mode analyses, we directly demonstrate the occurrence of two distinct receptor:Gq assemblies with different geometries whose relative populations parallel the activation state of the receptor. The first of these assemblies is a preassembled complex with the receptor in its basal conformation. This complex is specific of Gq and is not observed with Gi. The second one is an active assembly in which the receptor in its active conformation triggers G protein activation. The active complex is present even in the absence of agonist, in a direct relationship with the high constitutive activity of the ghrelin receptor. These data provide direct evidence of a mechanism for ghrelin receptor-mediated Gq signaling in which transition of the receptor from an inactive to an active conformation is accompanied by a rearrangement of a preassembled receptor:G protein complex, ultimately leading to G protein activation and signaling.G protein-coupled receptors (GPCRs), one of the largest cell surface receptor families, are involved in many cellular signaling processes (1). Based on this property, as well as their importance as drug targets, the molecular aspects of GPCR functioning have been extensively investigated. In particular, coupling to heterotrimeric G proteins has been the focus of numerous studies. Indeed, delineating the molecular mechanisms responsible for receptor:G protein interaction is absolutely required to better understand how signaling is controlled. Recent years have seen spectacular advances that have culminated in elucidation of the 3D structure of the β2-adrenergic receptor:Gs complex (2). Nevertheless, the need for further progress remains, in particular to fully understand the dynamics of this interaction. This is a crucial question, given that how the receptor interacts with its G protein partner governs signaling, and thus biological and pathophysiological responses.To date, two different models for GPCR:G protein interaction have been proposed: collision coupling and preassembly. Originally, it was proposed that receptors and G proteins couple by collision (3, 4). One of the main features of this model is that only activated receptors interact with G proteins. Since then, alternative models of signaling have been developed. One of these, the preassembly model, proposes that the receptor and the G protein make a complex even in the absence of agonist (5–8). Discriminating between the two models is crucial. Indeed, signaling outputs, such as the kinetics of G protein activation, will be significantly different depending on whether the ligand-free receptor is always in complex with its G protein or must first be activated by the agonist to recruit the G protein and trigger signaling. Moreover, it has been shown that GPCR conformational dynamics (9–11) and signaling in the absence of ligand are key features of GPCR functioning (12). How receptor constitutive activity and conformational dynamics relate to their coupling to the G protein remains an open question.Here we used the purified ghrelin receptor GHS-R1a to analyze the way in which this GPCR interacts with its G protein partners. Ghrelin is a neuroendocrine peptide hormone that acts through its cognate GPCR to control important biological processes, such as growth hormone secretion, food intake, and reward-seeking behaviors (13). Among the GPCRs, GHS-R1a has been shown to have one of the highest basal Gq activation levels both in vitro (10, 14) and in vivo (15, 16). The physiological relevance of GHS-R1a basal activity is substantiated by the occurrence of a natural human mutation in the GHS-R1a gene (A204E substitution in the second extracellular loop of the receptor) that dramatically decreases constitutive activity and is associated with a short-stature phenotype (17). Along with its importance in drug design, GHS-R1a is a prototype for peptide-activated class A GPCRs.To delineate the way in which the ghrelin receptor interacts with G proteins, we used monomeric GHS-R1a reconstituted in a membrane-mimicking environment, lipid discs, and a combination of innovative biochemical [labeling with unnatural amino acid (UAA)] and biophysical [lanthanide resonance energy transfer (LRET) and normal mode (NM) analyses] approaches. By doing so, we provide the first direct evidence that ghrelin-mediated signaling involves a complex dialogue between the conformational dynamics of the receptor and its ability to interact with the different G protein subtypes to which it is coupled. 相似文献
77.
Marjorie Crago Alayne Yates Larry E. Beutler Thomas G. Arizmendi 《The International journal of eating disorders》1985,4(1):79-87
In a sample of 384 college females enrolled in intramural sports programs from 1977 through 1982, height-weight ratios revealed no evidence of anorexia nervosa inclinations in this group, contrary to what might be expected based on reports of a dramatic increase in anorexia among young women during the time period studied. 相似文献
78.
Cindy L. Cain Antonella Surbone Ronit Elk Marjorie Kagawa-Singer 《Journal of pain and symptom management》2018,55(5):1408-1419
Palliative care is gaining acceptance across the world. However, even when palliative care resources exist, both the delivery and distribution of services too often are neither equitably nor acceptably provided to diverse population groups. The goal of this study was to illustrate tensions in the delivery of palliative care for diverse patient populations to help clinicians to improve care for all. We begin by defining and differentiating culture, race, and ethnicity, so that these terms—often used interchangeably—are not conflated and are more effectively used in caring for diverse populations. We then present examples from an integrative literature review of recent research on culture and palliative care to illustrate both how and why varied responses to pain and suffering occur in different patterns, focusing on four areas of palliative care: the formation of care preferences, communication patterns, different meanings of suffering, and decision-making processes about care. For each area, we provide international and multiethnic examples of variations that emphasize the need for personalization of care and the avoidance of stereotyping beliefs and practices without considering individual circumstances and life histories. We conclude with recommendations for improving palliative care research and practice with cultural perspectives, emphasizing the need to work in partnerships with patients, their family members, and communities to identify and negotiate culturally meaningful care, promote quality of life, and ensure the highest quality palliative care for all, both domestically and internationally. 相似文献
79.
Prevention of diabetes-induced albuminuria in transgenic rats overexpressing human aldose reductase 总被引:2,自引:0,他引:2
Ng DP Hardy CL Burns WC Muggli EE Kerr N McCausland J Alcorn D Adams TE Zajac JD Larkins RG Dunlop ME 《Endocrine》2002,18(1):47-56
Studies using pharmacologic inhibitors have implicated the enzyme aldose reductase in the pathogenesis of albuminuria and
diabetic renal disease. However, a clear conclusion is not easily drawn from such studies since these pharmacologic inhibitors
have nonspecific properties. To examine further the role of aldose reductase, we have overexpressed the human enzyme in a
transgenic rat model. Transgene expression in the kidney was predominantly localized to the outer stripe of the outer medulla,
compatible with the histotopography of the straight (S3) proximal tubule. The effect of enzyme overexpression on diabetes-induced
renal function and structure was then investigated. Contrary to what may have been anticipated from the previous enzyme inhibition
studies, diabetes-induced albuminuria was completely prevented by the overexpression of aldose reductase. No effect of overexpression
of aldose reductase on renal structure nor on urinary excretion of β2-microglobulin and N-acetyl-β-d-glucosaminidase was observed in this transgenic rat model. In conclusion, our study strongly suggests that multiple roles
for aldose reductase may give it a more complex place in diabetic nephropathy than is currently recognized. 相似文献
80.
Frédéric Janvier Katy Jeannot Sophie Tessé Marjorie Robert-Nicoud Hervé Delacour Christophe Rapp Audrey Mérens 《Antimicrobial agents and chemotherapy》2013,57(7):3408-3411
An NDM-1 carbapenemase-producing Pseudomonas aeruginosa isolate was recovered from a patient hospitalized in France after a previous hospitalization in Serbia. Genetic studies revealed that the blaNDM-1 gene was surrounded by insertion sequence ISAba125 and a truncated bleomycin resistance gene. This blaNDM-1 region was a part of the variable region of a new complex class 1 integron bearing IS common region 1 (ISCR1). The presence of ISPa7 upstream of this integron suggests insertion in a chromosomally located Tn402-like structure. 相似文献