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排序方式: 共有1024条查询结果,搜索用时 15 毫秒
41.
Michelle G Jansen Ludovica Griffanti Clare E Mackay Melis Anatürk Luca Melazzini Ann-Marie G de Lange Nicola Filippini Enik Zsoldos Kim Wiegertjes Frank-Erik de Leeuw Archana Singh-Manoux Mika Kivimki Klaus P Ebmeier Sana Suri 《Journal of cerebral blood flow and metabolism》2022,42(4):600
We characterize the associations of total cerebral small vessel disease (SVD) burden with brain structure, trajectories of vascular risk factors, and cognitive functions in mid-to-late life. Participants were 623 community-dwelling adults from the Whitehall II Imaging Sub-study with multi-modal MRI (mean age 69.96, SD = 5.18, 79% men). We used linear mixed-effects models to investigate associations of SVD burden with up to 25-year retrospective trajectories of vascular risk and cognitive performance. General linear modelling was used to investigate concurrent associations with grey matter (GM) density and white matter (WM) microstructure, and whether these associations were modified by cognitive status (Montreal Cognitive Asessment [MoCA] scores of < 26 vs. ≥ 26). Severe SVD burden in older age was associated with higher mean arterial pressure throughout midlife (β = 3.36, 95% CI [0.42-6.30]), and faster cognitive decline in letter fluency (β = −0.07, 95% CI [−0.13–−0.01]), and verbal reasoning (β = −0.05, 95% CI [−0.11–−0.001]). Moreover, SVD burden was related to lower GM volumes in 9.7% of total GM, and widespread WM microstructural decline (FWE-corrected p < 0.05). The latter association was most pronounced in individuals who demonstrated cognitive impairments on MoCA (MoCA < 26; F3,608 = 2.14, p = 0.007). These findings highlight the importance of managing midlife vascular health to preserve brain structure and cognitive function in old age. 相似文献
42.
Aortic valve hemodynamics in atrial fibrillation: Should the highest Doppler signal be used to estimate severity of aortic stenosis? 下载免费PDF全文
Said Alsidawi MD Sana Khan MD Sorin V. Pislaru MD PhD Vuyisile T. Nkomo MD MPH 《Echocardiography (Mount Kisco, N.Y.)》2018,35(6):869-871
Grading severity of AS in AF is complicated by varying stroke volumes associated with fluctuating maximum velocities and pressure gradients across the aortic valve. Current guidelines recommend averaging five continuous‐wave peak velocity and mean gradient (MG) Doppler signals across the aortic valve when estimating severity of AS in AF. However, it is unknown when grading severity of AS how the average of multiple Doppler signals vs the highest Doppler signal in AF compares to the Doppler signals when the patient is in normal sinus rhythm. We present a series of patients with AS who had two echocardiograms performed within 2‐4 months of each other, one when in normal sinus rhythm and one when in AF, and compare the aortic valve hemodynamics associated with the two rhythms. 相似文献
43.
44.
Martina Vendrame Stephanie Jackson Sana Syed Sanjeev V. Kothare Sanford H. Auerbach 《Sleep & breathing》2014,18(1):119-124
Purpose
We sought to examine the prevalence of central sleep apnea (CSA) and complex sleep apnea (CompSA) in patients with epilepsy and to examine their clinical profile, with respect to epilepsy type, etiology, medication use, and EEG abnormalities.Methods
We undertook a retrospective analysis of 719 consecutive patients with epilepsy who underwent polysomnography (PSG) at our institution between 2004 and 2011. Of the 458 patients with complete data, we excluded 42 patients with congestive heart failure or left ventricular ejection fraction <40 %. Comparison of clinical and PSG variables between the three groups were conducted with Fisher exact test and analysis of variance.Results
Out of 416 patients tested, 315 (75 %) had obstructive sleep apnea (OSA), 16 (3.7 %) had CSA, 33 (7.9 %) had CompSA. There were more males in the CSA and CompSA groups than in the OSA group (81.2, 81.8, and 59.6 %, respectively, p?=?0.04). Focal seizures were more prevalent in patients with CSA than in patients OSA or CompSA (62.5, 265, and 21.1 %, respectively, p?=?0.02).Conclusion
About 11 % of epilepsy patients have sleep-breathing disorders with central apneas, which is not higher than that in a general population. These data should be expanded with future research investigating the role of interictal, ictal, and postictal central apneas in epileptogenesis and epilepsy. 相似文献45.
Al-Khatib SM Allen LaPointe NM Kramer JM Chen AY Hammill BG Delong L Califf RM 《Journal of general internal medicine》2005,20(5):392-396
OBJECTIVE: To assess health care practitioners' ability to correctly measure the QT interval, and to identify factors and medications that may increase the risk of QT-interval prolongation and torsades de pointes. DESIGN: A cross-sectional analysis of a survey administered between April 2002 and March 2003. PARTICIPANTS AND SETTING: Health care practitioners attending Grand Rounds Conferences at 6 academic institutions in the United States in internal medicine and psychiatry and at 6 community hospitals in the same geographical areas as the academic institutions. INTERVENTION: Anonymous, self-administered questionnaire that included 20 questions on the QT interval. MEASUREMENTS AND MAIN RESULTS: Of approximately 826 attendees, 517 (63%) completed the survey. Of about 608 attendees of internal medicine conferences, 371 (61%) responded, and of about 208 attendees of psychiatry conferences, 146 (67%) responded. Of a total number of 20 questions, the median number of correct answers for the whole group was 10 (interquartile range 7-13). The median number of correct answers for internists was 12 (interquartile range 9-13), for psychiatrists 10 (interquartile range 7-13), and for other specialists 10 (interquartile range 5-13). Respondents who graduated between 1990 and 1999 and academicians performed significantly better overall than other respondents. Of the 517 respondents, 224 (43%) measured the QT interval correctly. Physicians in training and academicians were more likely to measure the QT interval correctly. CONCLUSION: The majority of health care practitioners cannot correctly measure the QT interval and cannot correctly identify factors and medications that can prolong the QT interval. Our findings suggest that greater attention to the QT interval is warranted to ensure safer use of QT prolonging medications. 相似文献
46.
Si-Ri-Gu-Leng Sana En-You Li Xi-Jin Deng Lei Guo 《World Journal of Clinical Cases》2021,9(33):10161-10171
BACKGROUNDDipeptidyl peptidase-4 (DPP4) is associated with cognitive dysfunction in patients with type 2 diabetes.AIMTo assess a possible relationship between serum DPP4 and cognitive function in perinatal pregnant women with gestational diabetes mellitus (GDM).METHODSThe study subjects were divided into three groups: GDM group (n = 81), healthy pregnant (HP) group (n = 85), and control group (n = 51). The Montreal Cognitive Assessment (MoCA) was used to assess the cognitive status of each group. Venous blood samples were collected to measure blood lipids, glycated hemoglobin, and glucose levels. For each participant, a 3-mL blood sample was collected and centrifuged, and the serum was collected. Blood samples were stored at -80 ℃, and DPP4, interleukin-6 (IL-6), and 8-iso-prostaglandin F2α (8-iso-PGF2α), and brain-derived neurotrophic factor (BDNF) were detected using ELISA.RESULTSThe MoCA scores in the GDM and HP groups were significantly different from those in the control group in terms of visuospatial/executive function and attention (P < 0.05); however, the scores were not significantly different between the GDM and HP groups (P > 0.05). In terms of language, the GDM group had significantly different scores from those in the other two groups (P < 0.05). In terms of memory, a significant difference was found between the HP and control groups (P < 0.05), as well as between the GDM and HP groups. The levels of DPP4, IL-6, and 8-iso-PGF2α in the GDM group were significantly higher than those in the HP and control groups (P < 0.05); however, the differences between these levels in the HP and control groups were not significant (P > 0.05). The level of BDNF in the GDM group was significantly lower than that in the HP and control groups (P < 0.05), although the difference in this level between the HP and control groups was not significant (P > 0.05).CONCLUSIONCognitive dysfunction in perinatal pregnant women with GDM mainly manifested as memory loss, which might be associated with elevated DPP4 levels. 相似文献
47.
Increased angiogenesis in the bone marrow of patients with systemic mastocytosis 总被引:1,自引:0,他引:1 下载免费PDF全文
Wimazal F Jordan JH Sperr WR Chott A Dabbass S Lechner K Horny HP Valent P 《The American journal of pathology》2002,160(5):1639-1645
Recent data suggest that angiogenesis in the bone marrow (BM) is augmented and associated with growth of neoplastic cells in various hematological malignancies. Systemic mastocytosis (SM) is a neoplasm affecting multilineage and mast cell (MC)-committed hemopoietic progenitors. In the present study, we have assessed the BM microvessel density (MVD) by CD34 immunohistochemistry in 21 patients with SM, 5 with cutaneous mastocytosis (no BM infiltrates), and 5 control cases (normal BM). The median BM MVD was significantly higher in SM compared to cutaneous mastocytosis or controls (P < 0.05). In addition, a significant correlation (r = 0.74) between the BM MVD and grade of MC infiltration (percent tryptase(+) BM infiltrates) was found in SM. Moreover, the MVD was higher in MC infiltrates compared to the nonaffected adjacent marrow (P < 0.05). Immunohistochemical staining revealed expression of vascular endothelial growth factor in MC infiltrates. The notion that SM is associated with increased BM angiogenesis and vascular endothelial growth factor expression may have implications for the biology of disease and development of new treatment strategies. 相似文献
48.
Sana Sahnoun Afifa Sellami Nozha Chakroun Malek Mseddi Hammadi Attia Tarek Rebai Saloua Lassoued 《Journal of assisted reproduction and genetics》2017,34(8):1067-1077
Purpose
To study the role of Toll-like receptor 4 (TLR4) in human spermatozoa and to assess sperm parameters, oxidative stress markers, and acrosome reaction in response to the stimulation of TLR4 by its ligand, the lipopolysaccharide (LPS), as a major endotoxin of Gram-negative bacteria.Methods
Our study was carried out in 73 sperm samples from patients undergoing semen analysis for couple infertility investigations. The studied patients were divided into three groups: normozoospermic fertile patients (n = 13), patients with abnormal and leukospermic semen (n = 13), and patients with abnormal and non-leukospermic semen (n = 47). TLR4 expression in human spermatozoa was initially analyzed by western blot. Sperm samples were incubated in the presence of LPS (200 ng/ml) for 18 h. Then, sperm motility and vitality were evaluated by microscopic observation and oxidative stress markers as malondialdehyde (MDA) and carbonyl groups (CG) were spectrophotometrically assessed in neat and selected sperm. A triple-stain technique was also performed to evaluate acrosome reaction in 15 sperm samples from infertile patients.Results
TLR4 expression was confirmed in human spermatozoa with a molecular weight of 69 kDa. In the normozoospermic group, no significant differences in sperm parameters and oxidative stress markers were shown after incubation with LPS in neat and selected sperms. Regarding samples from the non-leukospermic group, LPS reduced spermatozoa motility and vitality rates in selected sperm (P = 0.003; P = 0.004, respectively). A significant increase of MDA and CG levels was also detected (P = 0.01; P = 0.02, respectively). However, only the MDA levels were significantly increased (P = 0.01) in neat LPS-stimulated sperm. The same results were shown within the leukospermic group. The comparison between the two groups, leukospermic and non-leukospermic, in selected sperms showed a more important LPS effect in the leukospermic group significantly on motility and MDA rates (P = 0.006; P = 0.009, respectively). Furthermore, a significant decrease in reacted spermatozoa rate was detected in response to LPS in selected sperm samples from infertile men (P = 0.03).Conclusions
These findings indicate that human spermatozoa express TLR4 and respond to LPS stimulation with alterations in viability, motility, and the acrosome reaction implicating reactive oxygen species (ROS) production in sperm samples from infertile patients.49.
Dan Sunnemark Sana Eltayeb Maria Nilsson Erik Wallstr?m Hans Lassmann Tomas Olsson Anna-Lena Berg Anders Ericsson-Dahlstrand 《Journal of neuroinflammation》2005,2(1):17
Background
Multiple sclerosis (MS) is a chronic inflammatory disease of the central nervous system (CNS). It is associated with local activation of microglia and astroglia, infiltration of activated macrophages and T cells, active degradation of myelin and damage to axons and neurons. The proposed role for CX3CL1 (fractalkine) in the control of microglia activation and leukocyte infiltration places this chemokine and its receptor CX3CR1 in a potentially strategic position to control key aspects in the pathological events that are associated with development of brain lesions in MS. In this study, we examine this hypothesis by analyzing the distribution, kinetics, regulation and cellular origin of CX3CL1 and CX3CR1 mRNA expression in the CNS of rats with an experimentally induced MS-like disease, myelin oligodendrocyte glycoprotein (MOG)-induced autoimmune encephalomyelitis (EAE). 相似文献50.
TSP1 and MMP9 genetic variants in sporadic prostate cancer 总被引:2,自引:0,他引:2
Angiogenesis plays an important role in the initiation and progression of many malignancies including prostate cancer (PCa). Therefore, genes implicated in angiogenic pathways could be susceptibility candidate genes for this malignancy. In this respect, we investigated the impact of functional genetic variants of TSP1 (N700S) and MMP9 (-1562 C/T) genes on the development and progression of PCa. This case-control study included 101 PCa patients and 106 healthy controls analyzed by polymerase chain reaction -restriction fragment length polymorphism assay. No association was observed between any of the TSP1 genotypes and PCa risk or severity; however, subjects carrying one copy of the MMP9 T allele exhibited threefold higher risk of developing PCa (OR = 2.86; P = 0.004). Regarding prognostic value, a significant association was found between the occurrence of the MMP9 T allele and the high-grade tumor (OR = 3.21; P = 0.004) and the advanced disease (OR = 2.47; P = 0.026). We also analyzed the effect of the combined genotypes on PCa risk. The patients with two high-risk genotypes exhibited 2.8-fold higher risk of developing PCa than those with only low-risk genotypes, but the association was not statistically significant. These findings suggest that MMP9 polymorphism is an independent risk factor of PCa development and aggressiveness. 相似文献