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11.
Mark P. Plummer Mark E. Finnis Liza K. Phillips Palash Kar Shailesh Bihari Vishwanath Biradar Stewart Moodie Michael Horowitz Jonathan E. Shaw Adam M. Deane 《PloS one》2016,11(11)
ObjectiveStress induced hyperglycemia occurs in critically ill patients who have normal glucose tolerance following resolution of their acute illness. The objective was to evaluate the association between stress induced hyperglycemia and incident diabetes in survivors of critical illness.DesignRetrospective cohort study.SettingAll adult patients surviving admission to a public hospital intensive care unit (ICU) in South Australia between 2004 and 2011.PatientsStress induced hyperglycemia was defined as a blood glucose ≥ 11.1 mmol/L (200 mg/dL) within 24 hours of ICU admission. Prevalent diabetes was identified through ICD-10 coding or prior registration with the Australian National Diabetes Service Scheme (NDSS). Incident diabetes was identified as NDSS registration beyond 30 days after hospital discharge until July 2015. The predicted risk of developing diabetes was described as sub-hazard ratios using competing risk regression. Survival was assessed using Cox proportional hazards regression.ConclusionsStress induced hyperglycemia identifies patients at subsequent risk of incident diabetes. 相似文献
12.
Liza Bronner Murrison Ramya Ananthakrishnan Sumanya Sukumar Sheela Augustine Nalini Krishnan Madhukar Pai David W. Dowdy 《PloS one》2016,11(2)
Setting
Private practitioners are frequently the first point of healthcare contact for patients with tuberculosis (TB) in India. Inappropriate TB management practices among private practitioners may contribute to delayed TB diagnosis and generate drug resistance. However, these practices are not well understood. We evaluated diagnostic and treatment practices for active TB and benchmarked practices against International Standards for TB Care (ISTC) among private medical practitioners in Chennai.Design
A cross-sectional survey of 228 practitioners practicing in the private sector from January 2014 to February 2015 in Chennai city who saw at least one TB patient in the previous year. Practitioners were randomly selected from both the general community and a list of practitioners who referred patients to a public-private mix program for TB treatment in Chennai. Practitioners were interviewed using standardized questionnaires.Results
Among 228 private practitioners, a median of 12 (IQR 4–28) patients with TB were seen per year. Of 10 ISTC standards evaluated, the median of standards adhered to was 4.0 (IQR 3.0–6.0). Chest physicians reported greater median ISTC adherence than other MD and MS practitioners (score 7.0 vs. 4.0, P<0.001), or MBBS practitioners (score 7.0 vs. 4.0, P<0.001). Only 52% of all practitioners sent >5% of patients with cough for TB testing, 83% used smear microscopy for diagnosis, 33% monitored treatment response, and 22% notified TB cases to authorities. Of 228 practitioners, 68 reported referring all patients with new pulmonary TB for treatment, while 160 listed 27 different regimens; 78% (125/160) prescribed a regimen classified as consistent with ISTC. Appropriate treatment practices differed significantly between chest physicians and other MD and MS practitioners (54% vs. 87%, P<0.001).Conclusion
TB management practices in India’s urban private sector are heterogeneous and often suboptimal. Private providers must be better engaged to improve diagnostic capacity and decrease TB transmission in the community. 相似文献13.
Kerri M. Crawford Jonathan T. Bauer Liza S. Comita Maarten B. Eppinga Daniel J. Johnson Scott A. Mangan Simon A. Queenborough Allan E. Strand Katharine N. Suding James Umbanhowar James D. Bever 《Ecology letters》2019,22(8):1274-1284
Plant‐soil feedback (PSF) theory provides a powerful framework for understanding plant dynamics by integrating growth assays into predictions of whether soil communities stabilise plant–plant interactions. However, we lack a comprehensive view of the likelihood of feedback‐driven coexistence, partly because of a failure to analyse pairwise PSF, the metric directly linked to plant species coexistence. Here, we determine the relative importance of plant evolutionary history, traits, and environmental factors for coexistence through PSF using a meta‐analysis of 1038 pairwise PSF measures. Consistent with eco‐evolutionary predictions, feedback is more likely to mediate coexistence for pairs of plant species (1) associating with similar guilds of mycorrhizal fungi, (2) of increasing phylogenetic distance, and (3) interacting with native microbes. We also found evidence for a primary role of pathogens in feedback‐mediated coexistence. By combining results over several independent studies, our results confirm that PSF may play a key role in plant species coexistence, species invasion, and the phylogenetic diversification of plant communities. 相似文献
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Uzay Gormus Alka Chaubey Suresh Shenoy Yong Wee Wong Lee Yin Chan Bao Ping Choo Liza Oraha Anna Gousseva Fredrik Persson Lawrence Prensky Ephrem Chin Madhuri Hegde 《Current issues in molecular biology》2021,43(2):958
Background: Rolling-circle replication (RCR) is a novel technology that has not been applied to cell-free DNA (cfDNA) testing until recently. Given the cost and simplicity advantages of this technology compared to other platforms currently used in cfDNA analysis, an assessment of RCR in clinical laboratories was performed. Here, we present the first validation study from clinical laboratories utilizing RCR technology. Methods: 831 samples from spontaneously pregnant women carrying a singleton fetus, and 25 synthetic samples, were analyzed for the fetal risk of trisomy 21 (T21), trisomy 18 (T18) and trisomy 13 (T13), by three laboratories on three continents. All the screen-positive pregnancies were provided post-test genetic counseling and confirmatory diagnostic invasive testing (e.g., amniocentesis). The screen-negative pregnancies were routinely evaluated at birth for fetal aneuploidies, using newborn examinations, and any suspected aneuploidies would have been offered diagnostic testing or confirmed with karyotyping. Results: The study found rolling-circle replication to be a highly viable technology for the clinical assessment of fetal aneuploidies, with 100% sensitivity for T21 (95% CI: 82.35–100.00%); 100.00% sensitivity for T18 (71.51–100.00%); and 100.00% sensitivity for T13 analyses (66.37–100.00%). The specificities were >99% for each trisomy (99.7% (99.01–99.97%) for T21; 99.5% (98.62–99.85%) for T18; 99.7% (99.03–99.97%) for T13), along with a first-pass no-call rate of 0.93%. Conclusions: The study showed that using a rolling-circle replication-based cfDNA system for the evaluation of the common aneuploidies would provide greater accuracy and clinical utility compared to conventional biochemical screening, and it would provide comparable results to other reported cfDNA methodologies. 相似文献
16.
At the end of spermatogenesis, elongated spermatids are released from supporting Sertoli cells via the process termed spermiation. Previous studies have shown that spermiation failure occurs after hormone suppression, in which spermatids are retained instead of releasing. However, the molecular mechanisms involved in spermiation and spermiation failure are largely unknown. The aims of the present study were, first, to characterize the ultrastructural events associated with normal spermiation and spermiation failure using light and electron microscopy and, second, to investigate the localization of cell adhesion-associated (beta1-integrin and cadherins) and junction-associated molecules (integrin-associated kinase [ILK], beta-catenin, and espin) during these processes. Four adult Sprague-Dawley rats received testosterone and estradiol implants and FSH antibody (2 mg kg-1 day-1) for 7 days to suppress testicular testosterone and FSH and to induce spermiation failure. Four rats treated with saline were used as controls. After testosterone and FSH suppression, spermiation at the ultrastructural level appeared to be normal until the final disengagement of the spermatids from Sertoli cells (stage VIII), at which stage a large number of retained spermatids were noted. Immunohistochemical localization of espin showed that during spermiation, removal of the ectoplasmic specialization (ES) occurred 30 h before spermatid disengagement, suggesting that non-ES junctions mediate the spermatid-Sertoli cell interaction before and during disengagement. beta1-Integrin and beta-catenin remained associated with spermatids after ES removal and until disengagement; however, ILK was removed along with the ES. Though detectable, N-cadherin was not associated with the spermatid-Sertoli cell junction. After testosterone and FSH suppression, beta1-integrin, but not N-cadherin or beta-catenin, remained associated with spermatids that failed to spermiate. In conclusion, hormone suppression-induced spermiation failure is caused by defects in the disengagement of spermatids from the Sertoli cell, and this process likely is mediated by beta1-integrin in an ILK-independent mechanism. 相似文献
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The relationship between form and function in the lumbar vertebral column has been well documented among platyrrhines and especially catarrhines, while functional studies of postcranial morphology among strepsirrhines have concentrated predominantly on the limbs. This morphometric study investigates biomechanically relevant attributes of the lumbar vertebral morphology of 20 species of extant strepsirrhines. With this extensive sample, our goal is to address the influence of positional behavior on lumbar vertebral form while also assessing the effects of body size and phylogenetic history. The results reveal distinctions in lumbar vertebral morphology among strepsirrhines in functional association with their habitual postures and primary locomotor behaviors. In general, strepsirrhines that emphasize pronograde posture and quadrupedal locomotion combined with leaping (from a pronograde position) have the relatively longest lumbar regions and lumbar vertebral bodies, features promoting sagittal spinal flexibility. Indrids and galagonids that rely primarily on vertical clinging and leaping with orthograde posture share a relatively short (i.e., stable and resistant to bending) lumbar region, although the length of individual lumbar vertebral bodies varies phylogenetically and possibly allometrically. The other two vertical clingers and leapers, Hapalemur and Lepilemur, more closely resemble the pronograde, quadrupedal taxa. The specialized, suspensory lorids have relatively short lumbar regions as well, but the lengths of their lumbar regions are influenced by body size, and Arctocebus has dramatically longer vertebral bodies than do the other lorids. Lumbar morphology among galagonids appears to reflect a strong phylogenetic signal superimposed on a functional one. In general, relative length of the spinous processes follows a positively allometric trend, although lorids (especially the larger-bodied forms) have relatively short spinous processes for their body size, in accordance with their positional repertoire. The results of the study broaden our understanding of postcranial adaptation in primates, while providing an extensive comparative database for interpreting vertebral morphology in fossil primates. 相似文献
19.
In order to test the potential effect of prior exposure to different Cd concentrations on Cd uptake and accumulation, plants of Arabidopsis thaliana, including a phytochelatin-deficient mutant, cad1-3, and the wild type, were compared. For Cd uptake experiments, plants were grown for 1 week in nutrient solution containing different Cd concentrations (0, 0.05, 0.1, 0.25, 0.5, and 1.0 microM Cd(NO(3))(2)). Thereafter they were subjected to 0.5 microM Cd labelled with (109)Cd for 2 h. Uptake experiments with (109)Cd showed that the phytochelatin-deficient mutant cad1-3, accumulated less Cd than the wild type. Both a lower proportion and lower total amount of absorbed Cd were translocated to the shoot in cad1-3 plants compared to wild-type plants. Cadmium exposure also influenced the amounts of nutrients found, whereby after exposure to high Cd concentrations (0.5, 1.0 microM) during growth, cad1-3 roots contained less Fe, K, Mg, P, and S compared to roots of the wild type. In cad1-3 these elements decreased with increasing Cd concentration. The total Cd content in roots and shoots increased significantly with increasing Cd concentration during growth, although the increase was much less in cad1-3 plants. In time-dependent experiments of Cd uptake carried out between 15 and 120 min on plants not previously exposed to Cd, no significant difference in Cd accumulation between the mutant and wild type were found, although a smaller amount of Cd was translocated to the shoot in cad1-3 plants. The possibility that the differences in Cd accumulation in mutant and wild-type lines may be due to the cytosolic Cd regulation, which is inhibited by the complexation of Cd by phytochelatins, is discussed. 相似文献
20.