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排序方式: 共有438条查询结果,搜索用时 15 毫秒
1.
Sarah E. Henderson Shana A. Hall Jessica M. Callegari James A. Desjardins Sidney J. Segalowitz Karen L. Campbell 《Psychophysiology》2022,59(1):e13947
Recent work suggests that while voluntary episodic memory declines with age, involuntary episodic memory, which comes to mind spontaneously without intention, remains relatively intact. However, the neurophysiology underlying these differences has yet to be established. The current study used electroencephalography (EEG) to investigate voluntary and involuntary retrieval in older and younger adults. Participants first encoded sounds, half of which were paired with pictures, the other half unpaired. EEG was then recorded as they listened to the sounds, with participants in the involuntary group performing a sound localization cover task, and those in the voluntary group additionally attempting to recall the associated pictures. Participants later reported which sounds brought the paired picture to mind during the localization task. Reaction times on the localization task were slower for voluntary than involuntary retrieval and for paired than unpaired sounds, possibly reflecting increased attentional demands of voluntary retrieval and interference from reactivation of the associated pictures respectively. For the EEG analyses, young adults showed greater alpha event-related desynchronization (ERD) during voluntary than involuntary retrieval at frontal and occipital sites, while older adults showed pronounced alpha ERD regardless of intention. Additionally, older adults showed greater ERD for paired than unpaired sounds at occipital sites, likely reflecting visual reactivation of the associated pictures. Young adults did not show this alpha ERD memory effect. Taken together, these data suggest that involuntary memory is largely preserved with age, but this may be due to older adults' greater recruitment of top-down control even when demand for such control is limited. 相似文献
2.
Depression in women with polycystic ovary syndrome: clinical and biochemical correlates 总被引:7,自引:0,他引:7
Rasgon NL Rao RC Hwang S Altshuler LL Elman S Zuckerbrow-Miller J Korenman SG 《Journal of affective disorders》2003,74(3):299-304
BACKGROUND: We assessed the prevalence of mood disturbance among women with prospectively documented polycystic ovary syndrome (PCOS). METHODS: Thirty-two women with PCOS completed the Center for Epidemiological Studies-Depression Rating Scale (CES-D). Clinical and biochemical characteristics were assessed. RESULTS: Sixteen women had CES-D scores indicative of depression. Depression was associated with greater insulin resistance (P=0.02) and higher body mass index (P=0.05). Women receiving oral contraceptives for the treatment of PCOS were less depressed than patients not receiving treatment (P=0.03). LIMITATIONS: Possible selection bias, use of a screening tool alone without further diagnostic evaluation of depression, small samples size and lack of direct comparison with an age matched control group, should be considered in interpretation of these results. CONCLUSION: Findings suggest a high prevalence of depression among women with PCOS, and an association between depression and PCOS markers. 相似文献
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Adriana Benavides-Lara María de la Paz Barboza-Arguello Mauricio Gonzlez-Elizondo Marcela Hernndez-deMezerville Helena Brenes-Chacn Melissa Ramírez-Rojas Catalina Ramírez-Hernndez Nereida Arjona-Ortegn Shana Godfred-Cato Diana Valencia Cynthia A. Moore Alejandra Soriano-Fallas 《Emerging infectious diseases》2021,27(2):360
5.
Michael W. Panas Jaimie D. Sixsmith KeriAnn White Birgit Korioth-Schmitz Shana T. Shields Brian T. Moy Sunhee Lee Joern E. Schmitz William R. Jacobs Jr. Steven A. Porcelli Barton F. Haynes Norman L. Letvin Geoffrey O. Gillard 《Infection and immunity》2014,82(12):5317-5326
Mycobacteria, the etiological agents of tuberculosis and leprosy, have coevolved with mammals for millions of years and have numerous ways of suppressing their host''s immune response. It has been suggested that mycobacteria may contain genes that reduce the host''s ability to elicit CD8+ T cell responses. We screened 3,290 mutant Mycobacterium bovis bacillus Calmette Guerin (BCG) strains to identify genes that decrease major histocompatibility complex (MHC) class I presentation of mycobacterium-encoded epitope peptides. Through our analysis, we identified 16 mutant BCG strains that generated increased transgene product-specific CD8+ T cell responses. The genes disrupted in these mutant strains had disparate predicted functions. Reconstruction of strains via targeted deletion of genes identified in the screen recapitulated the enhanced immunogenicity phenotype of the original mutant strains. When we introduced the simian immunodeficiency virus (SIV) gag gene into several of these novel BCG strains, we observed enhanced SIV Gag-specific CD8+ T cell responses in vivo. This study demonstrates that mycobacteria carry numerous genes that act to dampen CD8+ T cell responses and suggests that genetic modification of these genes may generate a novel group of recombinant BCG strains capable of serving as more effective and immunogenic vaccine vectors. 相似文献
6.
Joseph M. Kindler Michelle Guo Joshua Baker Shana McCormack Saro H. Armenian Babette S. Zemel Mary B. Leonard Sogol Mostoufi-Moab 《Journal of bone and mineral research》2022,37(4):794-803
Allogeneic hematopoietic stem cell transplantation (alloHSCT) is a common therapy for pediatric hematologic malignancies. With improved supportive care, addressing treatment-related late effects is at the forefront of survivor long-term health and quality of life. We previously demonstrated that alloHSCT survivors had increased adiposity, decreased lean mass, and lower bone density and strength, 7 years (median) from alloHSCT compared to their healthy peers. Yet it is unknown whether these deficits persist. Our longitudinal study characterized changes in muscle and bone over a period of 3.4 (range, 2.0 to 4.9) years in 47 childhood alloHSCT survivors, age 5–26 years at baseline (34% female). Tibia cortical bone geometry and volumetric density and lower leg muscle cross-sectional area (MCSA) were assessed via peripheral quantitative computed tomography (pQCT). Anthropometric and pQCT measurements were converted to age, sex, and ancestry-specific standard deviation scores, adjusted for leg length. Muscle-specific force was assessed as strength relative to MCSA adjusted for leg length (strength Z-score). Measurements were compared to a healthy reference cohort (n = 921), age 5–30 years (52% female). At baseline and follow-up, alloHSCT survivors demonstrated lower height Z-scores, weight Z-scores, and leg length Z-scores compared to the healthy reference cohort. Deficits in MCSA, trabecular volumetric bone density, and cortical bone size and estimated strength (section modulus) were evident in survivors (all p < 0.05). Between the two study time points, anthropometric, muscle, and bone Z-scores did not change significantly in alloHSCT survivors. Approximately 15% and 17% of alloHSCT survivors had MCSA and section modulus Z-score < −2.0, at baseline and follow-up, respectively. Furthermore, those with a history of total body irradiation compared to those without demonstrated lower MCSA at follow-up. The persistent muscle and bone deficits in pediatric alloHSCT survivors support the need for strategies to improve bone and muscle health in this at-risk population. © 2022 American Society for Bone and Mineral Research (ASBMR). 相似文献
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8.
Hansruedi Glatt Kathryn E. Pietsch Shana J. Sturla Walter Meinl 《Archives of toxicology》2014,88(1):161-169
Acylfulvenes are a class of antitumor agents derived from illudin S, a sesquiterpenoid toxin isolated from mushrooms of the genus Omphalotus. Although DNA appears to be their major target, no data concerning mutagenicity of acylfulvenes are available in the literature, and limited data have been published on illudin S. Enzyme-mediated biotransformations have been demonstrated to influence the cytotoxicity of acylfulvenes. Illudin S and some acylfulvenes [e.g., (?)-6-hydroxymethylacylfulvene (HMAF)] are allylic alcohols with potential for enhanced cytotoxicity and genotoxicity by means of metabolic sulfation. Therefore, we studied the influence of various heterologously expressed human sulfotransferases (SULTs) on biological activities of illudin S and HMAF in bacterial and mammalian cells. (?)-Acylfulvene (AF) was tested as a congener lacking an allylic hydroxyl group. We found: (1) all three compounds were mutagenic in standard Salmonella typhimurium strains TA98, TA100 and TA104; (2) they induced gene mutations (at the hypoxanthine phosphoribosyl transferase locus) and sister chromatid exchange (SCE) in Chinese hamster V79 cells; (3) these effects were practically unaffected when human SULTs were expressed in the target bacteria or mammalian cells (using SCE as the endpoint); (4) illudin S demonstrated 40–600 times higher genotoxic activities than the semisynthetic acylfulvenes studied; it was positive in the SCE test even at a concentration of 0.3 nM; (5) genotoxicity in mammalian cells was observed at substantially lower concentrations of the compounds than required for a positive result in the bacterial test (400 nM with illudin S). We conclude that illudin S, HMAF and AF are potent genotoxicants and human SULTs do not play a significant role in their bioactivation. 相似文献
9.
Boonen A Patel V Traina S Chiou CF Maetzel A Tsuji W 《The Journal of rheumatology》2008,35(4):662-667
OBJECTIVE: To examine the longterm effect of etanercept (ETN) therapy on health-related quality of life (HRQOL) and utility in patients with ankylosing spondylitis. METHODS: Patients completing a 24-week placebo-controlled trial were continued on ETN in a 72-week open-label extension study. Short Form-36 (SF-36), EuroQOL-5D (EQ-5D), and EuroQOL visual analog scale (EQ-VAS) scores were collected at open-label baseline and every 12 weeks thereafter. Mental and physical component scores (MCS and PCS) of the SF-36, EQ-5D and SF-6D utility scores, and quality-adjusted life-years (QALY) were calculated. RESULTS: 257 patients [129 previous placebo (PLA) and 128 ETN recipients] enrolled in this open-label extension study, and 85% completed the 72-week followup. PCS, EQ-5D and SF-6D utilities, and EQ-VAS were significantly lower at open-label baseline in the previous PLA group (PLA/ETN group) than in the previous ETN group (ETN/ETN group; all p < 0.001). At week 12, PCS and MCS, EQ-5D and SF-6D utility scores, and EQ-VAS were similar in the PLA/ETN and ETN/ETN groups. As expected, mean change in EQ-5D in the PLA/ETN group was significantly greater than that for SF-6D (0.18 vs 0.06; p < 0.0001). HRQOL and utility improvements were maintained in both groups for up to 72 weeks. The average 72-week QALY gain per person in the PLA/ETN group was 0.24 and 0.10 for EQ-5D and SF-6D, respectively. CONCLUSION: Patients continuing ETN therapy sustained HRQOL and utility improvements attained during the original PLA-controlled trial. Patients previously taking PLA showed rapid and sustained improvements in HRQOL and utility and substantial QALY gain with ETN therapy. 相似文献
10.
Infections with hepatitis C virus (HCV) represent a substantial national and international public health burden. HCV has been associated with numerous extrahepatic conditions and can lead to metabolic derangements that are associated with atherosclerosis and cardiovascular disease. We investigated whether HCV infection is associated with an increased number of acute coronary syndrome (ACS) events among hospitalized patients in an inner-city tertiary hospital.We performed a matched (age, sex, and race/ethnicity) case-control study on patients at least 18 years old admitted to inpatient medical and cardiac services at the University of Maryland Medical Center from 2015 through 2018. The primary outcome was ACS and the primary exposure was HCV infection. Covariates of interest included: alcohol use, tobacco use, illicit drug use, hypertension, diabetes mellitus, human immunodeficiency virus infection, body mass index, dyslipidemia, and family history of coronary heart disease. Covariates with significant associations with both exposure and outcome in bivariate analyses were included in the multivariable analyses of the final adjusted model.There were 1555 cases and 3110 controls included in the final sample. Almost 2% of cases and 2.4% of controls were HCV infected. In adjusted models, there was no significant association found between experiencing an ACS event in those with HCV infection compared to those without HCV infection (odds ratio 0.71, 95% confidence interval 0.45–1.11).We found no significant association between HCV infection and ACS in our study population. However, given the mixed existing literature, the association between HCV and ACS warrants further investigation in future prospective cohort and/or interventional studies. 相似文献