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901.
902.
Rahul R. Karamchandani Farhaan Vahidy Suhas Bajgur Kim Yen Thi Vu H. Alex Choi Robert Kirk Hamilton Mohammad H. Rahbar Sean I. Savitz 《PloS one》2015,10(6)
Background and Purpose
Post-stroke depression (PSD) is common but is not routinely assessed for in hospitalized patients. As a Comprehensive Stroke Center, we screen all stroke inpatients for depression, though the feasibility of early screening has not been established. We assessed the hypothesis that early depression screening in stroke patients is feasible. We also explored patient level factors associated with being screened for PSD and the presence of early PSD.Methods
The medical records of all patients admitted with ischemic stroke (IS) or intracerebral hemorrhage (ICH) between 01/02/13 and 15/04/13 were reviewed. A depression screen, modified from the Patient Health Questionnaire-9, was administered (maximum score 27, higher scores indicating worse depression). Patients were eligible if they did not have a medical condition precluding screening. Feasibility was defined as screening 75% of all eligible patients.Results
Of 303 IS and ICH inpatients, 70% (211) were eligible for screening, and 75% (158) of all eligible patients were screened. More than one-third of all patients screened positive for depression (score > 4). Women (OR 2.06, 95% CI 1.06–4.01) and younger patients (OR 0.97, 95% CI 0.96–0.99) were more likely to screen positive. Screening positive was not associated with poor discharge/day 7 outcome (mRS > 3; OR 1.45, 95% CI 0.74–2.83).Conclusions
Screening stroke inpatients for depression is feasible and early depression after stroke is common. Women and younger patients are more likely to experience early PSD. Our results provide preliminary evidence supporting continued screening for depression in hospitalized stroke patients. 相似文献903.
904.
Pathogenic fungi have developed mechanisms to cope with stresses imposed by hosts. For Cryptococcus spp., this implies active defense mechanisms that attenuate and ultimately overcome the onslaught of oxidative stresses in macrophages. Among cellular pathways within Cryptococcus neoformans'' arsenal is the plasma membrane high-affinity Cch1-Mid1 calcium (Ca2+) channel (CMC). Here we show that CMC has an unexpectedly complex and disparate role in mitigating oxidative stress. Upon inhibiting the Ccp1-mediated oxidative response pathway with antimycin, strains of C. neoformans expressing only Mid1 displayed enhanced growth, but this was significantly attenuated upon H2O2 exposure in the absence of Mid1, suggesting a regulatory role for Mid1 acting through the Ccp1-mediated oxidative stress response. This notion is further supported by the interaction detected between Mid1 and Ccp1 (cytochrome c peroxidase). In contrast, Cch1 appears to have a more general role in promoting cryptococci survival during oxidative stress. A strain lacking Cch1 displayed a growth defect in the presence of H2O2 without BAPTA [(1,2-bis(2-aminophenoxy)ethane-N,N,N′,N′-tetraacetic acid, cesium salt] or additional stressors such as antimycin. Consistent with a greater contribution of Cch1 to oxidative stress tolerance, an intracellular growth defect was observed for the cch1Δ strain in the macrophage cell line J774A.1. Interestingly, while the absence of either Mid1 or Cch1 significantly compromises the ability of C. neoformans to tolerate oxidative stress, the absence of both Mid1 and Cch1 has a negligible effect on C. neoformans growth during H2O2 stress, suggesting the existence of a compensatory mechanism that becomes active in the absence of CMC. 相似文献
905.
Marnie L. Fusco Takao Hashiguchi Robyn Cassan Julia E. Biggins Charles D. Murin Kelly L. Warfield Sheng Li Frederick W. Holtsberg Sergey Shulenin Hong Vu Gene G. Olinger Do H. Kim Kevin J. Whaley Larry Zeitlin Andrew B. Ward Cory Nykiforuk M. Javad Aman Jody D. Berry Erica Ollmann Saphire 《PLoS pathogens》2015,11(10)
906.
Harlyn G. Skinner Larissa Calancie Maihan B. Vu Beverly Garcia Molly DeMarco Cam Patterson Alice Ammerman Jonathan C. Schisler 《PloS one》2015,10(5)
BackgroundHeart Healthy Lenoir is a transdisciplinary project aimed at creating long-term, sustainable approaches to reduce cardiovascular disease risk disparities in Lenoir County, North Carolina using a design spanning genomic analysis and clinical intervention. We hypothesized that residents of Lenoir County would be unfamiliar and mistrustful of genomic research, and therefore reluctant to participate; additionally, these feelings would be higher in African-Americans.MethodologyTo test our hypothesis, we conducted qualitative research using community-based participatory research principles to ensure our genomic research strategies addressed the needs, priorities, and concerns of the community. African-American (n = 19) and White (n = 16) adults in Lenoir County participated in four focus groups exploring perceptions about genomics and cardiovascular disease. Demographic surveys were administered and a semi-structured interview guide was used to facilitate discussions. The discussions were digitally recorded, transcribed verbatim, and analyzed in ATLAS.ti.
Results and Significance
From our analysis, key themes emerged: transparent communication, privacy, participation incentives and barriers, knowledge, and the impact of knowing. African-Americans were more concerned about privacy and community impact compared to Whites, however, African-Americans were still eager to participate in our genomic research project. The results from our formative study were used to improve the informed consent and recruitment processes by: 1) reducing misconceptions of genomic studies; and 2) helping to foster participant understanding and trust with the researchers. Our study demonstrates how community-based participatory research principles can be used to gain deeper insight into the community and increase participation in genomic research studies. Due in part to these efforts 80.3% of eligible African-American participants and 86.9% of eligible White participants enrolled in the Heart Healthy Lenoir Genomics study making our overall enrollment 57.8% African-American. Future research will investigate return of genomic results in the Lenoir community. 相似文献907.
Vivian F. Go Constantine Frangakis Nguyen Le Minh Carl Latkin Tran Viet Ha Tran Thi Mo Teerada Sripaipan Wendy W. Davis Carla Zelaya Pham The Vu David D. Celentano Vu Minh Quan 《PloS one》2015,10(5)
IntroductionInjecting drug use is a primary driver of HIV epidemics in many countries. People who inject drugs (PWID) and are HIV infected are often doubly stigmatized and many encounter difficulties reducing risk behaviors. Prevention interventions for HIV-infected PWID that provide enhanced support at the individual, family, and community level to facilitate risk-reduction are needed.Methods455 HIV-infected PWID and 355 of their HIV negative injecting network members living in 32 sub-districts in Thai Nguyen Province were enrolled. We conducted a two-stage randomization: First, sub-districts were randomized to either a community video screening and house-to-house visits or standard of care educational pamphlets. Second, within each sub-district, participants were randomized to receive either enhanced individual level post-test counseling and group support sessions or standard of care HIV testing and counseling. This resulted in four arms: 1) standard of care; 2) community level intervention; 3) individual level intervention; and 4) community plus individual intervention. Follow-up was conducted at 6, 12, 18, and 24 months. Primary outcomes were self-reported HIV injecting and sexual risk behaviors. Secondary outcomes included HIV incidence among HIV negative network members.ResultsFewer participants reported sharing injecting equipment and unprotected sex from baseline to 24 months in all arms (77% to 4% and 24% to 5% respectively). There were no significant differences at the 24-month visit among the 4 arms (Wald = 3.40 (3 df); p = 0.33; Wald = 6.73 (3 df); p = 0.08). There were a total of 4 HIV seroconversions over 24 months with no significant difference between intervention and control arms.DiscussionUnderstanding the mechanisms through which all arms, particularly the control arm, demonstrated both low risk behaviors and low HIV incidence has important implications for policy and prevention programming.
Trial Registration
ClinicalTrials.gov NCT01689545相似文献908.
Jorida oku David M Booth Jan Skoda Madison C Pedrotty Jennifer Vogel Kangning Liu Annette Vu Erica L Carpenter Jamie C Ye Michelle A Chen Peter Dunbar Elizabeth Scadden Taekyung D Yun Eiko NakamaruOgiso Estela AreaGomez Yimei Li Kelly C Goldsmith C Patrick Reynolds Gyorgy Hajnoczky Michael D Hogarty 《The EMBO journal》2022,41(8)
Most cancer deaths result from progression of therapy resistant disease, yet our understanding of this phenotype is limited. Cancer therapies generate stress signals that act upon mitochondria to initiate apoptosis. Mitochondria isolated from neuroblastoma cells were exposed to tBid or Bim, death effectors activated by therapeutic stress. Multidrug‐resistant tumor cells obtained from children at relapse had markedly attenuated Bak and Bax oligomerization and cytochrome c release (surrogates for apoptotic commitment) in comparison with patient‐matched tumor cells obtained at diagnosis. Electron microscopy identified reduced ER–mitochondria‐associated membranes (MAMs; ER–mitochondria contacts, ERMCs) in therapy‐resistant cells, and genetically or biochemically reducing MAMs in therapy‐sensitive tumors phenocopied resistance. MAMs serve as platforms to transfer Ca2+ and bioactive lipids to mitochondria. Reduced Ca2+ transfer was found in some but not all resistant cells, and inhibiting transfer did not attenuate apoptotic signaling. In contrast, reduced ceramide synthesis and transfer was common to resistant cells and its inhibition induced stress resistance. We identify ER–mitochondria‐associated membranes as physiologic regulators of apoptosis via ceramide transfer and uncover a previously unrecognized mechanism for cancer multidrug resistance. 相似文献
909.
Huong L. Vu Serge Troubetzkoy Huan H. Nguyen Michael W. Russell Jiri Mestecky 《Nucleic acids research》2000,28(7):e18
Accurate quantification of nucleic acids by competitive (RT)–PCR requires a valid internal standard, a reference for data normalization and an adequate mathematical model for data analysis. We report here an effective procedure for the generation of homologous RNA internal standards and a strategy for synthesizing and using a reference target RNA in quantification of absolute amounts of nucleic acids. Further, a new mathematical model describing the general kinetic features of competitive PCR was developed. The model extends the validity of quantitative competitive (RT)–PCR beyond the exponential phase. The new method eliminates the errors arising from different amplification efficiencies of the co-amplified sequences and from heteroduplex formation in the system. The high accuracy (relative error <2%) is comparable to the recently developed real time detection 5′-nuclease PCR. Also, corresponding computer software has been devised for practical data analysis. 相似文献
910.
K D Bottles E C Bullen D L Updike T K Vu E Phelps P Grammas E W Howard 《Biochimica et biophysica acta》1999,1428(2-3):147-160
Increased expression of gelatinase A is associated with both angiogenesis and alterations in blood vessel structure. Heart-derived endothelial cells derived from spontaneously hypertensive rats (SHR) were found to express significantly more gelatinase A in culture, both at the protein and mRNA level, than endothelial cells from normotensive Wistar-Kyoto (WKY) rats. Other matrix metalloproteinases, as well as their tissue inhibitors, were not differentially regulated. A 1683 bp gelatinase A promoter fragment linked to a luciferase reporter demonstrated up to 40-fold more activity when transfected into SHR-derived cells versus WKY-derived cells. The promoter region between -1324 and -1272, previously termed RE1, contributed up to a five-fold increase in basal promoter activity in both cells, but contributed only 12% of the promoter activity in SHR-derived cells compared to 85% in WKY-derived cells. In SHR-derived cells, but not in WKY-derived cells, a second region between -1435 and -1375, termed RE2, contributed 60% of the total activity of the 1683 bp promoter fragment. Both electrophoretic mobility shift assays and Southwestern blots demonstrated differences in RE2-specific binding factors in nuclear extracts derived from the two cell types. SHR-derived endothelial cells thus represent a new model system to study the regulation of gelatinase A expression, which itself may contribute to the abnormal vascular structure seen in the SHR. 相似文献