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991.
Spectral entropy (SE), also known as Shannon entropy, is a useful parameter for quantifying the global regularity of the electroencephalographic (EEG) signal. Hence, it is of interest in the assessment of the electrophysiological correlates of cognitive processing in schizophrenia. However, to date, SE has been barely used in studies comparing resting EEG recordings between patients and controls. In this work, we compared SE between resting baseline [?250 0] ms and active task [150 550] ms windows of a P300 task in 31 patients with schizophrenia and 38 controls. Moreover, we also calculated the median frequency (MF) and relative power in each frequency band for these windows to assess the correlates of the possible SE differences. Controls showed a significant (p < 0.0029) SE decrease (i.e., meaning higher signal regularity) from baseline to the active task window at parietal and central electrode sites. This SE decrease from baseline to active conditions was significantly lower in patients. In controls, this SE decrease was accompanied by a statistically significant decrease in MF (i.e., a significant slowing of the EEG activity), not observed in patients. In this latter group, the difference in SE between resting baseline and active task windows was inversely correlated to positive and total symptoms scores, as measured with the positive and negative symptoms scale. Our data support the relevance of SE in the study of cerebral processing in schizophrenia.  相似文献   
992.
Although it was originally characterized as a constituent of focal adhesions in fibroblasts, focal adhesion kinase (FAK) is now considered to be not only a mediator of adhesion processes but also a crucial regulator of guidance and a modulator of gene expression. FAK is the main transducer of the integrin signaling required to stabilize the actin cytoskeleton. However, additional activities have been described over the years. In the brain, FAK deserves particular attention as it is found in various alternatively spliced forms – these distributed in multiple subcellular compartments or bound to multiple partners. Moreover, its signaling involves not only phosphorylation but also ubiquitination and proteolysis. Several experimental cell models demonstrate that FAK increases or decreases migration, participates in differentiation and contributes to plasticity events. In addition, this kinase is linked to cell survival in cancer and apoptosis. This review focuses on the diversity of events involving brain‐located forms of FAK.  相似文献   
993.
The present study investigated whether cannabidiol (CBD), a major non-psychoactive constituent of marijuana, protects against hippocampal neurodegeneration and cognitive deficits induced by brain ischemia in adult mice. Male Swiss mice were subjected to a 17 min of bilateral common carotid artery occlusion (BCCAO) and tested in the Morris water maze 7 days later. CBD (3, 10, and 30 mg/kg) was administered 30 min before and 3, 24, and 48 h after BCCAO. After behavioral testing, the brains were removed and processed to evaluate hippocampal cell survival and degeneration using Nissl staining and FluoroJade C histochemistry, respectively. Astroglial response was examined using immunohistochemistry for glial fibrillary acidic protein (GFAP). CBD (3–30 mg/kg) improved spatial learning performance in BCCAO mice. The Nissl and FJC staining results showed a decrease in hippocampal neurodegeneration after CBD (10 and 30 mg/kg) treatment. GFAP immunoreactivity was also decreased in ischemic mice treated with CBD (30 mg/kg). These findings suggest a protective effect of CBD on neuronal death induced by ischemia and indicate that CBD might exert beneficial therapeutic effects in brain ischemia. The mechanisms that underlie the neuroprotective effects of CBD in BCCAO mice might involve the inhibition of reactive astrogliosis.  相似文献   
994.

Background

Neurotrophic factors have been investigated in the pathophysiology of alcohol and drug dependence and have been related to early life stress driving developmental programming of neuroendocrine systems.

Methods

We conducted a follow-up study that aimed to assess the plasma levels of glial cell line–derived neurotrophic factor (GDNF), brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), neurotrophin-3 (NT3) and neurotrophin-4/5 (NT4/5) in crack users during 3 weeks of early abstinence in comparison with healthy controls. We performed a comprehensive clinical assessment in female inpatients with crack cocaine dependence (separated into 2 groups: participants with (CSA+) and without (CSA−) a history of childhood sexual abuse) and a group of nonuser control participants.

Results

Our sample included 104 women with crack cocaine dependence and 22 controls; of the women who used crack cocaine, 22 had a history of childhood sexual abuse and 82 did not. The GDNF plasma levels in the CSA+ group increased dramatically during 3 weeks of detoxification. In contrast, those in the CSA− group showed lower and stable levels of GDNF under the same conditions. Compared with the control group, BDNF plasma levels remained elevated and NGF levels were reduced during early abstinence. We found no differences in NT3 and NT4/5 between the patients and controls. However, within-group analyses showed that the CSA+ group exhibited higher levels of NT4/5 than the CSA− group at the end of detoxification.

Limitations

Some of the participants were using neuroleptics, mood stabilizers or antidepressants; our sample included only women; memory bias could not be controlled; and we did not investigate the possible confounding effects of other forms of stress during childhood.

Conclusion

This study supports the association between early life stress and peripheral neurotrophic factor levels in crack cocaine users. During early abstinence, plasmastic GDNF and NT4/5 were the only factors to show changes associated with a history of childhood sexual abuse.  相似文献   
995.
996.
997.
Despite the great efficacy of current antiviral preventive strategies, hCMV infection is still a major complication after renal transplantation, significantly challenging patient and graft survival. This issue seems to be explained because of the rather poor immunologic monitoring of the antiviral immune response. An important body of evidence has shown that monitoring the hCMV‐specific T‐cell response, at different time points of the transplant setting, seems to add crucial information for predicting the risk of viral infection, thus potentially helping individualization of therapeutic decision‐making in clinical transplantation. While several immune‐cellular assays have shown its capability for accurately monitoring hCMV‐specific T‐cell responses, only few such as the IFN‐γ ELISPOT and the ELISA based technology assays might be reliable for its application in the clinic. Nonetheless, an important effort has to be made among the transplant community to standardize and validate such immune assays. Noteworthy, large‐scale prospective randomized trials are highly warranted to ultimately introduce them in current clinical practice as a part of the highly desired personalized medicine.  相似文献   
998.

Purpose

Quality of life (QL) is a key outcome for advanced disease cancer patients. The European Organization for Research and Treatment of Cancer (EORTC) has developed the QLQ-C15-PAL questionnaire, a short version of the QLQ-C30 for palliative care. The aim of the present study is to validate the QLQ-C15-PAL for use with Spanish patients with bone metastasis.

Methods

For this study, we used a consecutive sample of stage IV cancer patients with bone metastases who started radiotherapy with palliative intention. Two assessments were proposed for each patient: one on the first day of treatment and one a month after the end of the radiotherapy sessions. Psychometric evaluation of the structure, reliability, and validity was undertaken.

Results

One hundred and sixteen patients completed the first questionnaire and seventy five completed the second. Multitrait scaling analysis showed that all items met the standards for convergent validity, and all except the fatigue scale met the standards for divergent validity. Cronbach’s coefficient met the 0.7 alpha criterion on all scales except pain (second assessment). Most QLQ-C15-PAL areas had low-to-moderate correlations with the other areas. Significant differences appeared in the comparisons between groups with regard to: patients who died before the second assessment (six areas); patients receiving chemotherapy before starting radiotherapy in the two assessments (three and four areas, respectively); the performance status in the two assessments (nine and eight areas); and the number of RT sessions received (four). Quality of life was better in the second assessment in nine areas.

Conclusion

The QLQ-C15-PAL is a reliable and valid instrument when applied to a sample of Spanish patients. These results are in line with those of other validation studies.  相似文献   
999.
One of the territories of dental psychosomatics is the link between personality characterisctics and dental status. The aim of the present study was to survey the relationship between temperament and character factors and dental status in police students. It can be hypothesized, that some temperament factors can increase the risk for dental health problems. After dental screening 792 police students completed the Temperament and Character Inventory (TCI) devised by Cloninger. 57.5% of students rated their own teeth as being in good or very good condition, and only 2.8% as bad condition. In persons rating their dental status as “good”, the average DMFT was 9.23±5.01 (mean±S.D.). In students assessing their own oral health as bad, TCI results showed that a higher percentage of students displayed extravagance, impulsiveness, disorderliness than the overall population. Among the students with good self-assessment but bad teeth, there was a higher percentage of students displaying passivity, low assertiveness, and introversion. The temperament and character factors may have negative consequences for students in an institution which exposes them to high stress level. It may be useful to screen these students using subjective health questionnaires in order to permit more effective efforts to positive health behaviour.  相似文献   
1000.
This study describes the insecticidal activity of a novel Bacillus thuringiensis Cry-related protein with a deduced 799 amino acid sequence (~89 kDa) and ~19% pairwise identity to the 95-kDa-aphidicidal protein (sequence number 204) from patent US 8318900 and ~40% pairwise identity to the cancer cell killing Cry proteins (parasporins Cry41Ab1 and Cry41Aa1), respectively. This novel Cry-related protein contained the five conserved amino acid blocks and the three conserved domains commonly found in 3-domain Cry proteins. The protein exhibited toxic activity against the green peach aphid, Myzus persicae (Sulzer) (Homoptera: Aphididae) with the lowest mean lethal concentration (LC50 = 32.7 μg/mL) reported to date for a given Cry protein and this insect species, whereas it had no lethal toxicity against the Lepidoptera of the family Noctuidae Helicoverpa armigera (Hübner), Mamestra brassicae (L.), Spodoptera exigua (Hübner), S. frugiperda (J.E. Smith) and S. littoralis (Boisduval), at concentrations as high as ~3.5 μg/cm2. This novel Cry-related protein may become a promising environmentally friendly tool for the biological control of M. persicae and possibly also for other sap sucking insect pests.  相似文献   
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