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11.
The platelet and the neuron: Two cells in focus in migraine   总被引:1,自引:0,他引:1  
Reports of platelet abnormalities in migraine are abundant, and the present paper discusses the role of platelets in the migraine aetiology. Platelets are considered good models for pre- and post-synaptic functions in serotonergic neurons. We propose that migraine is associated with a lowered threshold for stimulus response in both platelets and serotonergic neurons and that the alterations in platelet function reflect central serotonergic disturbances. The platelet abnormalities in migraine approach those found in depression, and there are several links between the two disorders. The clinical significance of platelet hyperactivity in migraineurs for the occurrence of thrombotic disorders is also discussed. Studies of platelet functions in migraine, using platelets as models for serotonergic neurons, may broaden our understanding of the neuronal processes that take place during a migraine attack. The platelet can also be an investigative tool for better understanding of the modes of action of anti-migraine drugs.  相似文献   
12.
OBJECTIVE: Apathy is among the most frequent neuropsychiatric symptoms in dementia, particularly Alzheimer disease. The Apathy Evaluation Scale (AES) has been widely employed for assessing apathy in different patient groups. To further facilitate the usage of the AES, an abbreviated version was constructed. METHOD: On basis of a sample of 356 nursing home residents, a cross-validation procedure was carried out to develop a brief version of the AES. According to a thorough clinical examination, 85% of the residents were demented, 8% presented with mild cognitive impairment, whereas 7% did not present any cognitive deficits. After subdividing the patient group into two matched samples, the first subsample was used to identify problematic items due to defined psychometric and content-related criteria. The original 18-item scale was thus reduced to 10 items. Psychometric properties of the shortened version were subsequently reassessed in the second subsample. RESULTS: The short version demonstrated favorable psychometric properties that could be confirmed by cross-validation with the second sample. Correlations with the original full-length version were high (r = 0.97 for both subsamples); the shortened scale yielded no substantial losses regarding internal consistency or construct validity (correlations with the respective subscales of the Neuropsychiatric Inventory). CONCLUSION: The frequency of apathetic symptoms in the nursing home residents included confirms the clinical importance of apathy for understanding dementia. Given this specific patient population, setting, and mode of data collection, the short-version AES seems to be a valuable and time-efficient instrument for assessing apathy.  相似文献   
13.
The main goal of the present work was to longitudinally examine consequences of long‐term moderately elevated levels of stress for various health outcomes. To address this issue, data covering 10 years was used from the ongoing Swedish population‐based prospective Betula Study. Based on the ratings on a validated self‐reported stress scale, matched subsamples between 40 and 65 years of age were divided into a high (n = 137) and low (n = 211) stress group. The reported incidence of cardiovascular, diabetes, psychiatric, tumour and musculoskeletal diseases was assessed 5 and 10 years after baseline (baseline = 1993–1995) without contaminating effects of past health history. The incidence of diseases 5 years after baseline assessment showed no differences between the groups. After 10 years, there was a significantly higher incidence of psychiatric diseases, mainly depression in the high‐stress group as well as a significant effect for tumours, although the number of cases was low. Although moderately elevated stress level may have a possible impact on psychiatric diseases especially depression and some tumours, it seems that prolonged moderate stress does not appear to be harmful to other stress‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd.  相似文献   
14.
OBJECTIVE: The aim of this study was to determine the effects of quality improvement programs for pressure ulcer prevention by conducting a follow-up survey in a hospital in Sweden. DESIGN: A cross-sectional survey design with comparison between data collected in 2002 and 2004. SETTING AND SUBJECTS: All inpatient areas were surveyed in the surgical, medical, and geriatric departments in a university hospital. A total of 369 patients were included. INSTRUMENTS: The European Pressure Ulcer Advisory Panel data collection form including some additional questions. METHODS: The 1-day survey was conducted on March 23, 2004. Each patient was visited by 2 registered nurses, who inspected the patient's skin for any pressure ulcer classified according to the EPUAP grading system. RESULTS: There were no significant differences in gender, age, or Braden score between the patients in surgical, medical, or geriatric care in 2002 and 2004. The overall prevalence of pressure ulcers was 33.3% (grade 1 excluded: 10.9%) in 2002 and 28.2% (grade 1 excluded: 14.1%) in 2004. In surgical care, the prevalence was reduced from 26.8% to 17.3% (P = .051). In medical care, the prevalence was 23.6% in 2002 and 26.7% in 2004. Corresponding prevalence figures for geriatric care were 59.3% and 50.0%. A quarter of the patients in surgical care, a third in medical care, and more than half in geriatric care had a pressure ulcer upon arrival at the ward. The use of pressure-reducing mattresses had increased significantly from 16.0% to 42.7% in medical care (P = .000). CONCLUSIONS: The EPUAP methodology has facilitated the introduction of pressure ulcer as a quality indicator at hospital level. Pressure ulcer prevalence surveys with a standardized methodology should be repeated on a regular basis in order to stimulate quality improvement.  相似文献   
15.
Malignant rhabdoid tumors are highly aggressive childhood tumors. Recently, all of the malignant rhabdoid tumors, whatever their location, have been related to the inactivation of the hSNF5/INI1 gene. A subset of cerebral tumors, associated with malignant rhabdoid tumors or isolated ones arising in siblings, showed similar molecular alterations. We report for the first time in monozygotic twins a congenital disseminated malignant rhabdoid tumor in one twin and a cerebellar tumor mimicking a medulloblastoma in the other. Molecular analysis revealed similar alterations for both tumors: a deletion of exon 7 of the hSNF5/INI1 gene in one allele, and a point mutation in the same exon in the other, suggesting a common genetic pathway. Analysis of constitutional DNA revealed a germline mutation. These findings are in favor of a common etiology for rhabdoid tumor and a subset of brain tumors developing in infancy.  相似文献   
16.
Summary Stereological techniques on electron microscopy micrographs were used to evaluate the morphological changes of cultured islet cells that had been exposed to alloxan or 6-hydroxydopamine.Trypan Blue exclusion by cells cultured for 3 days indicated that the cells were 100% viable. Electron microscopy revealed that nearly all of the surviving cultured cells were cells.Exposure to 5 mmol/l alloxan or 1–5 mmol/l 6-hydroxydopamine for 10 or 30 min caused a general swelling of the cultured cells with a concomitant swelling of mitochondria and nuclei. The size of the secretory granules was not affected by the drugs. Only 3–10% of the cells excluded Trypan Blue after exposure to 5 mmol/l alloxan or 6-hydroxydopamine.The data conform with the hypothesis that a primary action of alloxan and 6-hydroxydopamine is at the plasma membrane level of cells.Abbreviations and definitions A cell Cell profile area (µm2), surface area of one cell section surface - V n Nuclear volume density (%), number of points over the nucleus divided by the number of points over the total cell area × 100 - V m Mitochondrial volume density (%), number of points over mitochondria divided by hits over the cytoplasm (points over the cell minus points over the nucleus) × 100 - V g Granular volume density (%), number of points over granules divided by hits over the cytoplasm × 100  相似文献   
17.
We have initiated large-scale sequencing of the third smallest chromosome of the CL Brener strain of Trypanosoma cruzi and we report here the complete sequence of a contig consisting of three cosmids. This contig covers 93.4 kb and has been found to contain 20–30 novel genes and several repeat elements, including a novel chromosome 3-specific 400-bp repeat sequence. The intergenic sequences were found to be rich in di- and trinucleotide repeats of varying lengths and also contained several known T. cruzi repeat elements. The sequence contains 29 open reading frames (ORFs) longer than 700 bp, the longest being 5157 bp, and a large number of shorter ORFs. Of the long ORFs, seven show homology to known genes in parasites and other organisms, whereas four ORFs were confirmed by sequencing of cDNA clones. Two shorter ORFs were confirmed by a database homology and a cDNA clone, respectively, and one RNA gene was identified. The identified genes include two copies of the gene for alanine-aminotransferase as well as genes for glucose-6-phosphate isomerase, protein kinases and phosphatases, and an ATP synthase subunit. An interesting feature of the sequence was that the genes appear to be organized in two long clusters containing multiple genes on the same strand. The two clusters are transcribed in opposite directions and they are separated by an ~20-kb long, relatively GC-rich sequence, that contains two large repetitive elements as well as a pseudogene for cruzipain and a gene for U2snRNA. It is likely that this strand switch region contains one or more regulatory and promoter regions. The reported sequence provides the first insight into the genome organization of T. cruzi and shows the potential of this approach for rapid identification of novel genes.  相似文献   
18.
Histological examination of the metastatic rat mammary adenocarcinoma line MTLn3 showed that macrophages and mast cells were frequently localized at the tumor periphery in the stromal tissues adjacent to the zones of tumor invasion. The interactions of these host cells with tumor cells and tumor-associated fibroblasts could be important in stimulating the production of extracellular matrix-degrading enzymes that facilitate tumor invasion and metastatic spread. Therefore, we examined the effects of isolated, activated macrophages and mast cells on the secretion of collagenolytic activities by normal fibroblasts, metastatic mammary adenocarcinoma cells and tumor-associated fibroblasts. Medium from activated macrophages or degranulated mast cells stimulated significant increases in production of collagenolytic activities by normal and tumor-associated fibroblasts and MTLn3 tumor cells. Medium from activated macrophages that had been pretreated with medium from degranulated mast cells, however, were less stimulatory to fibroblasts and tumor cell production of collagenolytic activities than medium from degranulated mast cells alone. We also examined the effects of two cytokines, interleukin-1 and tumor necrosis factor-a on activated macrophage- and degranulated mast cell-stimulation of fibroblast and tumor cell collagenolytic activities. The two cytokines alone or in combination stimulated increased production of collagenolytic activities by fibroblasts and tumor cells. Addition of the cytokines to degranulated mast cell products resulted in secretion of higher collagenolytic enzyme activities by normal fibroblasts (but not by tumor-derived fibroblasts or tumor cells) than with degranulated mast cell product-treatment of either target cell alone. Cytokines used in combination with macrophage-conditioned medium were less effective in stimulating fibroblast and tumor cell collagenase activities than cytokines alone. Thus normal infiltrating host cells such as macrophages and mast cells can have profound effects on the production of degradative enzymes by tumor cells and tumor-associated stromal fibroblasts.  相似文献   
19.
Real-time PCR was evaluated as a quantitative diagnostic method for Chlamydia pneumoniae infection using different respiratory samples. Real-time PCR had efficiency equal to or better than that of nested touchdown PCR. This study confirmed sputum as the best sampling material to detect an ongoing C. pneumoniae infection.  相似文献   
20.
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