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61.
Fragile X-associated tremor/ataxia syndrome (FXTAS), a late-onset movement disorder affecting FMR1 premutation carriers, is associated with cerebral and cerebellar lesions. The aim of this study was to test whether computational anatomy can detect similar patterns in asymptomatic FMR1 premutation carriers (mean age 46.7 years) with qualitatively normal -appearing grey and white matter on brain MRI. We used a multimodal imaging protocol to characterize brain anatomy by automated assessment of gray matter volume and white matter properties. Structural changes in the hippocampus and in the cerebellar motor network with decreased gray matter volume in lobule VI and white matter alterations of the corresponding afferent projections through the middle cerebellar peduncles are demonstrated. Diffuse subcortical white matter changes in both hemispheres, without corresponding gray matter alterations, are only identified through age × group interactions. We interpret the hippocampal fimbria and cerebellar changes as early alterations with a possible neurodevelopmental origin. In contrast, progression of the diffuse cerebral hemispheric white matter changes suggests a neurodegenerative process, leading to late-onset lesions, which may mark the imminent onset of FXTAS.  相似文献   
62.
Mechanisms relating Type D personality to poor health are largely unknown, with autonomic nervous system function being a candidate. This study examined the physiologic response to cold stress. Undergraduates (N = 101, 84% female) underwent a cold pressor test. An electrocardiogram, impedance cardiogram, and blood pressure were recorded. Type D personality was assessed by self‐report questionnaire. Type D was associated with increased systolic and diastolic blood pressure reactivity. Exploratory analyses showed Type D men to respond with increased respiratory sinus arrhythmia (i.e., higher parasympathetic activity), and decreased pre‐ejection period (i.e., larger sympathetic activity), while Type D women showed a reciprocal response pattern. In conclusion, Type D personality was associated with an exaggerated hemodynamic response to cold stress, which may contribute to an increased risk of hypertension in Type D individuals.  相似文献   
63.
Human plasmacytoid dendritic cells (PDC) are blood dendritic cell antigen 2 (BDCA2) and blood dendritic cell antigen 4 (BDCA4) positive leukocytes that do not express common lineage markers. They have been described as proinflammatory innate immune cells and are the major source of αIFN in the human body. PDC-derived secretion of type I IFNs upon triggering of nucleic acid-sensing toll-like receptors (TLR) primes immune cells to rapidly respond to microbial stimuli and promotes a Th1 response. Here, we report that human PDC express CD36 and CD61 (β3 integrin), both involved in uptake of apoptotic cells and in induction of tolerance. Freshly isolated PDC and PDC within human blood leukocytes constitutively express IL-10. Thus, PDC may possess a so far neglected role in propagation of immune tolerance.  相似文献   
64.
Background. Cardiac remodeling is ultimately regulated by components of the extracellular matrix (ECM). We investigated the important role that growth factors play in the regulation of ECM remodeling that occurs as a consequence of myocardium damage.

Methods and results. Rats were submitted to the ligation of the left anterior coronary artery and pcDNA3-vascular endothelial growth factor (VEGF)165 was immediately injected intramyocardially in the treated group. The animals were divided into large size myocardium infarction (LMI) and small size myocardium infarction, with or without gene transfer. The plasmid-containing DNA encoding VEGF165 was injected into the cardiac muscle and its effect was observed on the ECM components. Glycosaminoglycans were identified and quantified by agarose gel based electrophoresis and ELISA as well as immunocytochemistry to examine specific cathepsin B, heparanase, and syndecan-4 changes. The amounts of hyaluronic acid (HA; p < 0.005), DS, chondroitin sulfate, and heparan sulfate (p < 0.001) were significantly increased in the LMI treated group in comparison to the other groups, which correlates with the decrease in the expression of heparanase. A decrease in the molecular mass of HA was found in the scar tissue of treated group.

Conclusions. The data obtained strongly support the idea that changes in the ECM and its components are important determinants of cardiac remodeling after myocardium infarct and may be essential for inflammatory response and attempt to stabilize the damage and provide a compensatory mechanisms to maintain cardiac output since the ECM components analyzed are involved with angiogenesis, cell proliferation and differentiation.  相似文献   
65.
Pilocytic astrocytoma (PA) is the most frequent solid neoplasm in childhood. It has a good 5‐year overall survival (90% in childhood and 52% in adults). However, up to 20% of patients experience residual tumor growth, recurrence, and death. Although the main genetic alteration of PAs, including KIAA1549:BRAF fusion, involves chromosome 7q34, we previously found frequent loss in chr9q34.3 locus in a small subset of these tumors. Among the genes present in this locus, EGFL7 is related to poor prognosis in several tumor types. In this study, we aimed to assess EGFL7 expression through immunohistochemistry, and to evaluate its prognostic value in a series of 64 clinically and molecularly well‐characterized pilocytic astrocytomas. We found high expression of EGFL7 in 71.9% of patients. Low EGFL7 expression was associated with older patients, the mean age mainly older than 11 years (P = 0.027). EGFL7 expression was not associated with presence of KIAA1549:BRAF fusion, BRAF mutation, FGFR1 mutation, nor FGFR1 duplication. Moreover, high EGFL7 expression was associated with high FGFR1 (P = 0.037) and 5′‐deoxy‐5′‐methyltioadenosine phosphorylase (MTAP) (P = 0.005) expression, and with unfavorable outcome of patients (P = 0.047). Multivariate analysis revealed low EGFL7 expression related to older patients and high EGFL7 expression related to retained expression of MTAP. In addition, we found a borderline significance of unfavorable outcome and high EGFL7 expression. Finally, EGFL7 expression was not associated with overall or event‐free survival of PA patients. Our findings point to EGFL7 expression as a novel candidate prognostic marker in PA, which should be further investigated.  相似文献   
66.
Journal of NeuroVirology - This study aims to characterize the acute neurological manifestations caused by DENV, ZIKV, and YFV during hospitalization; identify the risk factors associated with...  相似文献   
67.
Clinical and Experimental Medicine - Cirrhotic patients with chronic hepatitis C should be monitored for the evaluation of liver function and screening of hepatocellular carcinoma even after...  相似文献   
68.
Methotrexate (MTX) is a widely used chemotherapeutic agent; nevertheless, the nephrotoxicity associated with its use has limited its clinical use. Rebamipide (REB) is a gastro-protective agent with diverse promising biological activities. Here, we investigated the renoprotective effects of REB against MTX-induced nephrotoxicity in rats. Male Wistar rats were allocated into four groups: the normal control group, the REB group (100 mg kg−1 day−1, PO, for 12 days), the MTX group (which received a single injection of 20 mg/kg, ip), and the REB + MTX group (which received 100 mg kg−1 day−1 REB for 7 days before and 5 days after being injected with 20 mg/kg MTX). Interestingly, MTX triggered kidney injury, characterized by renal dysfunction along with histopathological alterations. Moreover, increased reactive oxygen species level and inflammatory response were detected in the kidney of MTX-treated rats. However, REB prevented MTX-induced oxidative kidney injury and boosted an antioxidant balance. Mechanistically, REB markedly activated the NRF-2 protein and upregulated the expression of both SIRT-1 and FOXO-3 genes. Additionally, REB administration strongly inhibited the inflammatory response by downregulating both NF-κB-p65 and TLR-4. Finally, the coadministration of REB and MTX activated the mTOR/PI3K/AKT signaling pathway. Simultaneously, REB treatment attenuated the reduction in glomerular size, the widening of the capsular spaces, and the tubular cell damage due to MTX administration. Taken together, these results indicate the potential of REB as adjuvant therapy to prevent nephrotoxicity in patients receiving MTX treatment.  相似文献   
69.
The present study investigated the susceptibility of Acanthamoeba spp. trophozoites to two multipurpose systems for cleaning and maintenance of contact lenses. Three strains of trophozoites from the ATCC (A. castellani T4, A. castellani Neff, and A. polyphaga) and two Acanthamoeba isolates obtained from swimming pools (PT5 and PO1) were placed in monoxenic culture. To test their survival in cleaning solutions for contact lenses, the trophozoites were exposed for 4 and 24 h to two multipurpose solutions (A and B), and were then inoculated into a new monoxenic culture. Amoebic growth on the plates was observed after 72 h of incubation. Trophozoites from all three ATCC strains and one isolate from a swimming pool (PO1) grew in all plates after 4 h of exposure to solutions A and B. After 24 h, the ATCC strains and the PO1 isolate showed growth in most of the plates treated. Only the PT5 isolate showed susceptibility to both solutions over the time intervals tested. The two solutions were not completely effective against most strains and isolates over the time intervals tested. These results are important, since species of Acanthamoeba are widely distributed in the environment and are potential agents of eye pathologies.  相似文献   
70.
McArdle disease, also known as glycogen storage disease type V, is an autosomal recessive disease due to the absence of myophosphorylase activity, leading to the complete disruption of glycogen breakdown in muscles. We present a rare case of a Caucasian male, aged 26 years, who developed rhabdomyolysis-induced acute renal failure and uremic encephalopathy. Neurological examination and histopathological studies supported the diagnosis of McArdle disease. The severity of his symptoms necessitated urgent hemodialysis, upon which the patient reported improvement in status. Acute renal failure in McArdle disease usually resolves with supportive treatment and maintenance of regular physical activity. Nevertheless, in more severe cases, intensive care with urgent hemodialysis may be needed. A multidisciplinary approach is necessary for the adequate management of similar cases.  相似文献   
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