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771.
772.
Fotheringham J Akhyani N Vortmeyer A Donati D Williams E Oh U Bishop M Barrett J Gea-Banacloche J Jacobson S 《The Journal of infectious diseases》2007,195(3):450-454
One-half of bone-marrow transplant (BMT) and stem-cell transplant recipients have reactivation of latent human herpesvirus (HHV)-6 2-4 weeks after transplant. Although the detection of viral DNA, RNA, and antigen in brain material confirmed active HHV-6 variant B infection, peak viral loads in cerebrospinal fluid (CSF) and serum occurred 2-4 weeks before death and decreased to low levels before or at autopsy. All autopsy samples consistently demonstrated HHV-6 active infection in the hippocampus. Astrocytic cells positive for viral antigen provided support for an HHV-6-specific tropism for hippocampal astrocytes. HHV-6 DNA in CSF and serum may not reflect the level of active viral infection in the brain after BMT. 相似文献
773.
A spatio-temporal wavelet-chaos methodology for EEG-based diagnosis of Alzheimer's disease 总被引:1,自引:0,他引:1
A spatio-temporal wavelet-chaos methodology is presented for analysis of EEGs and their delta, theta, alpha, and beta sub-bands for discovering potential markers of abnormality in Alzheimer's disease (AD). The non-linear dynamics of the EEG and EEG sub-bands are quantified in the form of the correlation dimension (CD), representing system complexity, and the largest Lyapunov exponent (LLE), representing system chaoticity. The methodology is applied to two groups of EEGs: healthy subjects and AD patients. The eyes open and eyes closed conditions are investigated to evaluate the effect of visual input and attention. EEGs from different loci in the brain are investigated to discover areas of the brain responsible for or affected by changes in CD and LLE. It is found that the wavelet-chaos methodology and the sub-band analysis developed in this research accurately characterizes the non-linear dynamics of non-stationary EEG-like signals with respect to the EEG complexity and chaoticity. It is concluded that changes in the brain dynamics are not spread out equally across the spectrum of the EEG and over the entire brain, but are localized to certain frequency bands and electrode loci. New potential markers of abnormality were discovered in this research for both eyes open and closed conditions. 相似文献
774.
Guillermo Gervasini Roza Ghotbi Eleni Aklillu Carmen San Jose Agustin Cabanillas Junko Kishikawa Julio Benitez Juan Antonio Carrillo 《Environmental and molecular mutagenesis》2013,54(2):124-132
In this study, we analyzed the influence of CYP1A2 genetic variation and enzyme activity on lung cancer risk in a high‐incidence area. A total of 95 lung cancer patients and 196 controls were genotyped for the ?3860G/A, ?3113A/G, ?2467T/delT, ?739T/G, and ?163C/A polymorphisms in the 5′‐untranslated region of the gene. In addition, a subset of 70 patients and 115 controls were phenotyped by high‐performance liquid chromatography determination of the caffeine metabolic ratio (CMR). The ?2467T/delT polymorphism and the CYP1A2*1V haplotype (‐163C>A, ?2467T>delT) were inversely associated with lung cancer risk (odds ratio [OR] = 0.47 [0.2–0.9]; P = 0.02 and OR = 0.13 [0.02‐1.0]; P = 0.04; respectively). In addition, the CYP*1A/*1V and *1F (‐163C>A)/*1D (?163C>A, ?2467T>delT) diplotypes were absent in the patients group, whereas accounting for 7.1% (P = 0.017) and 5.6% (P = 0.037) of controls, respectively. Mean CMR was significantly higher in patients than in controls (10.50 ± 17.31 vs. 6.52 ± 6.26, P = 0.01) but regression analyses did not yield significant ORs for the association with lung cancer risk. Similarly, no significant correlations were found between any genetic variant and enzyme activity. Several CYP1A2 haplotypes and diplotypes containing the ?2467delT variant were associated with lower lung cancer risk; however, they did not correlate with significant changes in CYP1A2 metabolic activity toward caffeine. Environ. Mol. Mutagen., 2013. © 2012 Wiley Periodicals, Inc. 相似文献
775.
Leila Katoozian Nahid Tahan Maryam Zoghi Babak Bakhshayesh 《Journal of the National Medical Association》2018,110(6):547-552
Background
Spasticity is one of the most important causes of disability after stroke. In spite of high incidence of spasticity, little is known about the relationship between the occurrence and the development of spasticity. This study aimed to determine risk-factors of post stroke spasticity.Methods
This was an observational study of 149 persons with first ever stroke. The following parameters were assessed: Stroke severity, Spasticity, Disability and Joint contracture.Results
Prevalence of spasticity was between 17–25% during the first 3 months after stroke. The onset of spasticity was 13.79% and 4.16% at 1 and 3 months after stroke respectively. The prevalence of spasticity in the upper extremity was significantly more than lower extremity at 1 month. Spasticity was significantly more severe in the upper extremity than lower extremity. In patients with hemorrhagic stroke Odds ratios of spasticity was 2.5 times more than persons with ischemic stroke (P = 0.0210. The Odds ratios of severe spasticity at 1 and 3 months were 1.66 and 1.75 times more than the first week (P = 0.024, P = 0.042 respectively).Conclusions
Post stroke spasticity is more common in persons with hemorrhagic stroke, severe paresis and lower functional abilities. The most incidence of spasticity happens in the first month after stroke. 相似文献776.
Maedeh Arabian Nahid Aboutaleb Mansoureh Soleimani Marjan Ajami Rouhollah Habibey Hamidreza Pazoki-Toroudi 《Advances in medical sciences》2018,63(2):213-219
Purpose
Pharmacologic preconditioning, through activating several mechanisms and mediators, can increase the tolerance of different tissues against ischemia/reperfusion (I/R) injury. Recent studies have shown that morphine preconditioning has protective effects in different organs, especially in the heart. Nevertheless, its mechanisms are not well elucidated in the brain. The present study aimed to clarify whether the activation of mitochondrial KATP (mKATP) channels in chronic morphine (CM) preconditioning could decrease hippocampus damage following I/R injury.Materials and methods
CM preconditioning was performed by the administration of additive doses of morphine for 5 days before I/R injury induction. I/R injury was induced by the occlusion of bilateral common carotid arteries. The possible role of mKATP channels was evaluated by the injection of 5-hydroxydecanoate (5-HD) before I/R injury. Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) was performed to detect apoptosis in hippocampal neurons. The expressions of B-cell lymphoma-2 (Bcl-2) and Bcl-2-associated X protein (BAX) and levels of malondialdehyde (MDA) and catalase (CAT) enzymes were assessed.Results
CM attenuated apoptosis in the hippocampal CA1 neurons (P < 0.001 vs I/R), and mKATP channel blocking with 5-HD significantly increased apoptosis (P < 0.001 vs CM + I/R). CM increased CAT activity (P < 0.05 vs I/R) and Bcl-2 protein expression (P < 0.01 vs I/R), while it decreased MDA level (P < 0.05 vs I/R) and BAX protein expression (P < 0.05 vs I/R). Pretreatment with 5-HD abolished all the above-mentioned effects of CM.Conclusions
These findings describe novel evidence whereby CM preconditioning in hippocampal CA1 neurons can improve oxidative stress and apoptosis through the activation of mKATP channels and eventually protect the hippocampal tissue against I/R injury. 相似文献777.
Hassan Mehrad-Majd Sahar Ravanshad Ali Moradi Nahid Khansalar Maryam Sheikhi Javad Akhtari 《Pathology, research and practice》2019,215(6):152426
BackgroundSeveral studies have indicated that lncRNA loc285194 is aberrantly expressed in many types of cancer. This meta-analysis was performed to elucidate the potential role of lncRNA loc285194 as a prognostic marker in malignant tumors.MethodsAn electronic search of PubMed, Medline, Embase, and Web of Science was performed to identify all eligible papers related to the prognostic impact of lncRNA loc285194 expression in cancer. Hazard ratios (HR) and 95% confidence intervals (CI) were extracted from the included studies to explore the association between lncRNA loc285194 expression and patient overall and disease-free survival (OS & DFS). The odds ratios (ORs) were also calculated to assess the association between lncRNA loc285194 expression and clinicopathological parameters.ResultsA total of 14 eligible articles with 1215 patients were included in this meta-analysis. Meta-results revealed that low expression of lncRNA loc285194 was significantly correlated with poorer overall survival (OS; HR = 2.34; 95% CI, 1.78–3.06; P < 0.001) and disease-free survival (DFS; HR = 2.66; 95% CI, 1.95–3.64; P = 0.001) rates in cancer patients. Low lncRNA loc285194 expression was also found to be significantly associated with lymph node metastasis (LNM; OR = 2.17; 95% CI, 1.23–3.83; P = 0.007), and distant metastasis (DM; OR = 2.49; 95% CI, 1.26–4.91; P = 0.009).ConclusionsThis study demonstrated that decreased level of lncRNA loc285194 was associated with poor clinical outcomes for patients with different types of cancer, supporting a promising potential biomarker for prognosis and metastasis in human cancers. 相似文献
778.
Danial FazilatPanah Nahid Ahmadi Dariush Moslemi Masoumeh Karimi Alireza Taji Mansoureh Dehghani Ali Emadi Torghabeh Zahra Keshtpour Amlashi Mohammadreza Saghafi Maedeh Alsadat Fatemi 《Clinical Case Reports》2021,9(10)
Despite the fact that prostate cancer is the most prevalent cancer in men, metastases to the central nervous system including leptomeningeal involvement by prostate carcinoma is a rare event. The prognosis of metastatic prostate cancer is very poor due to lack of CNS penetrating therapeutic agents. 相似文献