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11.
Effective therapeutic intervention in Alzheimer disease (AD) will be most effective if it is directed at early events in the pathogenic sequence. The cholinergic deficit may be such an early event. In the present study, the brains of 26 subjects who had no history of cognitive loss and who were in early histopathologic stages of AD (average Braak stage less than II) were examined at autopsy to determine whether a cortical cholinergic decrement was associated with Abeta concentration or deposition. In the superior frontal and inferior temporal gyri, the choline acetyltransferase (ChAT) activity of plaque-containing cases was significantly decreased (p < 0.05, unpaired, two-tailed t-tests), measuring 70.9% and 79.5%, respectively, relative to plaque-free cases. In the inferior temporal gyrus, Spearman's rank correlation analysis showed that ChAT activity had a significant inverse correlation with Abeta concentration (p = 0.075; r = -0.3552). The results indicate that the cholinergic deficit is established at an early histopathologic stage of AD, before the onset of clinical symptoms.  相似文献   
12.
Rogers  AE; Hafer  LJ; Iskander  YS; Yang  S 《Carcinogenesis》1998,19(7):1269-1273
Epidemiological studies suggest that tea may reduce cancer risk, and in laboratory rodents, chemopreventive effects of tea or purified extracts of tea have been demonstrated in lung, gastrointestinal tract and skin. There is some evidence of chemoprevention by tea in the mammary gland, but the data are not conclusive. In order to evaluate more fully the possible influence of black tea on 7,12-dimethylbenz[a]anthracene (DMBA)-induced mammary gland tumors in the female S-D (Sprague-Dawley) rat, three large studies were performed: experiment 1, tumorigenesis in rats fed AIN-76A diet and given 25 mg/kg DMBA and 1.25 or 2.5% whole tea extract or water to drink; experiment 2, tumorigenesis in rats given 15 mg/kg DMBA and the same diet and fluids as in experiment 1; experiment 3, tumorigenesis in rats fed control or HF (high fat, corn oil) diet and given 15 mg/kg DMBA and 2% tea or water to drink. Tea was given throughout the experiment; DMBA was given by gastric gavage at 8 weeks of age. There was no consistent effect of tea on tumorigenesis in rats fed AIN-76A diet; there was, however, evidence in experiment 3 of a reduction of tumorigenesis by tea in rats fed the HF diet. In experiment 3, rats fed the HF diet and given water showed the expected increase in tumor burden (number and weight) compared with rats fed control diet. However, rats fed the HF diet and given 2% tea showed no increase in tumor burden; their tumor burden was significantly lower than in rats fed the HF diet and given water (P < 0.01) and was not different from rats fed control diet and given water or tea. In addition, in experiment 3, the number of malignant tumors per tumor- bearing rat was increased by the HF diet in water-drinking rats (P < 0.01) but not in tea-drinking rats. Therefore, it appears that tea partially blocked the promotion of DMBA-induced mammary tumorigenesis by the HF diet.   相似文献   
13.
Due to the COVID-19 pandemic, the closure of educational institutions was executed during the period of lockdown. This subsequently led to alterations in daily routines and emotional distress, particularly among university students, affecting their sleep quality resulting in disturbance of immune functioning and mood regulation. Hence, the present study aimed to measure students' sleep quality during the first few months of the lockdown period. This study is a cross-sectional, single-centred survey that was done by distributed electronic questionnaire. The e-questionnaire was divided into 4 sections that assessed socio-demographic characteristics, sleep quality, psychological state and engagement in physical activity. Exactly 248 valid responses were received, 82 % female students. Students with poor sleep quality were three times greater than those with good sleep quality. No association were found between physical activity and sleep quality. However, a significant positive relationship between sleep quality and psychological state was observed (p < 0.01). In conclusion, this study suggests that the majority of pharmacy students in UiTM Puncak Alam are poor sleepers and psychological distress negatively affects sleep quality but, is mainly due to stress. Thus, interventions such as stress management programs and mental health support can be taken by the faculty's management to overcome this problem.  相似文献   
14.
Formal assessment of cognitive decline with cognitive tests can be difficult, requiring either two measurement points or a comparison of 'hold' with 'don't hold' tests. Informant-based assessment provides an alternative approach because informants can adopt a longitudinal perspective and directly rate cognitive change. A study was carried out to assess the validity of informant ratings collected by means of the Informant Questionnaire on Cognitive Decline in the Elderly (IQCODE). A community sample of 500 subjects aged 74 or over underwent four cognitive tests on two occasions 3½ years apart. On the second occasion, informants filled out the IQCODE. Subjects rated as having moderate or severe decline were found to have greater change on the cognitive tests. These findings support the validity of informant ratings of cognitive decline.  相似文献   
15.
Gassmann  AE; van Furth  R 《Blood》1975,46(1):51-64
The effect of azathioprine on the kinetics of peripheral blood monocytes and peritoneal macrophages was studied in normal mice and in mice in which an inflammatory reaction was provoked. Two dosage levels were used: a high dose of 200mg/kg which is the maximum tolerated daily dose in mice, and low dose of 3 mg/kg which is about equivalent to a nontoxic, immunosuppressive, anti-inflammatory dose in man. The number of peripheral blood monocytes decreases gradually during azathioprine treatment of normal mice, the extent and duration being dependent on the dose and duration of administered over a period of 9 days gives an almost complete reduction, and a low dose (3 mg/kg) given for the same period results in a reduction of about 50%. This effect seems to be reversible, because when treatment is stopped the number of monocytes starts to increase 24-48 hr later. The number of peritoneal macrophages is only affected when a high dose (200 mg/kg) is given over a long period; a low dose has virtually no effect. In mice in which an inflammatory reaction was prevoked in the peritoneal cavity, the normally occurring increase in the numbers of both peripheral blood monocytes and peritoneal macrophages was suppressed, the extent being dependent on the dose of azathioprine administered. Labeling studies with 3H-thymidine indicated that the reduction of peripheral blood monocytes and peritoneal macrophages in the inflammatory exudate is due to a diminished monocyte production.  相似文献   
16.
In four healthy volunteers, we analyzed in detail the immediate in vivo effects on circulating neutrophils of subcutaneous administration of 300 micrograms of granulocyte colony-stimulating factor (G-CSF). Neutrophil activation was assessed by measurement of degranulation. Mobilization of secretory vesicles was shown by a decrease in leukocyte alkaline phosphatase content of the circulating neutrophils. Furthermore, shortly postinjection, Fc gamma RIII was found to be upregulated from an intracellular pool that we identified by immunoelectron microscopy as secretory vesicles. Intravascular release of specific granules was shown by increased plasma levels of lactoferrin and by upregulation of the expression of CD66b and CD11b on circulating neutrophils. Moreover, measurement of fourfold elevated plasma levels of elastase, bound to its physiologic inhibitor alpha 1- antitrypsin, indicated mobilization of azurophil granules. However, no expression of CD63, a marker of azurophil granules, was observed on circulating neutrophils. G-CSF--induced mobilization of secretory vesicles and specific granules could be mimicked in whole blood cultures in vitro, in contrast to release of azurophil granules. Therefore, we postulate that the most activated neutrophils leave the circulation, as observed shortly postinjection, and undergo subsequent stimulation in the endothelial microenvironment, resulting in mobilization of azurophil granules. Our data demonstrate that G-CSF should be regarded as a potent immediate activator of neutrophils in vivo.  相似文献   
17.
Antigenic modulation is one of many factors determining the effectiveness of monoclonal antibody (MoAb)-mediated therapy. To select the isotype of a CD19 MoAb most suitable for radioimmunotherapy of patients with B-cell malignancies, we studied the influence of MoAb isotype on modulation, after binding of the MoAb to different cell-line cells. The CD19-IgG1 MoAb was found to induce modulation of CD19 antigens on Daudi cell line cells more rapidly than did its IgG2a switch variant. We provide evidence that this difference in modulation rate is caused by the expression of Fc gamma receptor II (Fc gamma RII) on these cells. Experiments aimed at elucidating the mechanism of Fc gamma RII involvement in modulation induction by CD19-IgG1 showed that Fc gamma RII did not comodulate with CD19 MoAbs. However, cocrosslinking of CD19 and Fc gamma RII with CD19-IgG1 MoAb resulted in enhanced calcium mobilization in Daudi cells. This increased signal induction accompanies the enhanced capping and subsequent modulation of CD19 antigens. Because Fc gamma RII is expressed in varying densities on malignant B cells in all differentiation stages, our results have implications for the MoAb isotype most suitable for use in MoAb-based therapy of patients with B-cell malignancies.  相似文献   
18.
Anal cancer is one of the most common non‐AIDS‐defining malignancies in the era of combination antiretroviral therapy. Its precursor lesion, anal intraepithelial neoplasia (AIN), is highly prevalent in HIV‐infected populations. More than 90% of anal squamous cell cancers are attributable to human papillomavirus (HPV). While the biology of HPV‐related intraepithelial neoplasia is consistent across lower anogenital sites, the natural history of AIN is not well established and cannot be assumed to be identical to that of cervical intraepithelial neoplasia. Screening strategies to prevent anal cancer should be developed based on robust natural history data in HIV‐infected and uninfected populations. Likewise, treatments need to be tested in randomized clinical trials, and reserved for those at significant risk of progression to cancer. This review covers the epidemiology, pathogenesis and immunology of HPV infection, AIN and anal cancer, and summarizes the current diagnosis, screening and treatment strategies in HIV‐infected adults.  相似文献   
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