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51.
Twenty patients with AIDS who had intracranial lesions underwent both brain biopsy and cerebro-spinal fluid (CSF) examination to compare histological diagnosis with the polymerase chain reaction (CSF-PCR) for the identification of infectious agents. CSF-PCR was performed for herpes simplex virus, varicella zoster virus, cytomegalovirus (CMV), JC virus (JCV), Epstein-Barr virus (EBV), Toxoplasma gondii and Mycobacterium tuberculosis. A definitive diagnosis was obtained by brain biopsy in 14 patients (2 with astrocytoma, 12 with brain infection). CSF-PCR was positive for EBV DNA in 3 of 3 cases of primary cerebral lymphoma, positive for JCV DNA in 6 of 7 biopsy-proven (and one autopsy-proven) cases of progressive multifocal leukoencephalopathy (PML). CSF-PCR was positive for CMV DNA in one biopsy-proven and one autopsy-proven case of CMV encephalitis (the former also had PML) and positive for M. tuberculosis DNA in one case of tuberculous encephalitis. None of the five toxoplasmic encephalitis cases (one definite, four presumptive) were T. gondii DNA positive. There was close correlation between histology and CSF-PCR for CMV encephalitis, PML and PCL. Antitoxoplasma therapy affected the sensitivity of both histological and CSF-PCR methods. Received: 8 November 1995 Received in revised form: 9 July 1996 Accepted: 19 July 1996  相似文献   
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The SEPIVAC study (Italian initials for "epidemiologic study of incidence of acute cerebrovascular disease") is a community-based epidemiologic survey of incidence and outcome of cerebrovascular disease in the territory of the 6th Local Health Unit, Umbria, Italy, where 49,101 people live. All cases were registered with the study either by notification from general practitioners or by check of hospital admission within the study area and in the two hospitals of Perugia. Death certificates were looked at as well. Patients were registered with the study when the clinical picture fulfilled the definition of stroke and transient ischemic attack (TIA) adopted for this study. Patients were followed up at approximately 30 days and 6 months. During the first year of the study (September 1, 1986 to August 31, 1987), 189 cases were registered: 108 suffered a "first ever in a lifetime" stroke, 30 a recurrent stroke, and 51 a "first ever in a lifetime" transient ischemic attack. Sixty-one percent of patients (71% of first strokes) had a computed tomography scan. For our study, the crude annual incidence rate of first stroke was 2.2 per 1,000 (confidence intervals 1.81-2.66); the standardized rate to the European population was 1.36 (confidence intervals 1.06-1.74). At least 83% of first strokes were due to cerebral ischemia; in 26 cases a clinical diagnosis of lacunar ischemia was made. The 30-day case fatality rate was 21%; 25% of our patients had recovered completely or almost completely after 1 month.  相似文献   
54.
This study investigated the effect of adenosine in the forced swimming test (FST) and the tail suspension test (TST) in mice, and the contribution of adenosine A1 and A2A receptors to adenosine's antidepressant-like effect. The immobility time in the FST was reduced by adenosine given either by i.p. (5-10 mg/kg) or i.c.v. (0.01-10 microg/site) route. Adenosine (1-10 mg/kg, i.p.) also produced an antidepressant-like effect in the TST. No treatment affected locomotion in an open-field. The anti-immobility effect of adenosine (10 mg/kg, i.p.) in the FST was prevented by i.p. pretreatment of mice with caffeine (3 mg/kg), DPCPX (2 mg/kg) and ZM241385 (1 mg/kg). CHA (0.05 mg/kg, i.p.) and DPMA (1-5 mg/kg, i.p.) also produced an antidepressant-like effect in the FST. This is the first report of an antidepressant-like effect of adenosine in mice, apparently mediated through an interaction with A1 and A2A receptors.  相似文献   
55.
Lactoferrin, a member of the transferrin family of approximately 80 kDa, consists of a single polypeptide chain folded in two symmetric, globular lobes (N- and C-lobes), each able to bind one ferric ion. This glycoprotein, found in physiological fluids of mammals, plays an important role in immune regulation and in defense mechanisms against bacteria, fungi, parasites, and viruses. Although the antiviral activity of lactoferrin is one of the major biological functions of such protein, the mechanism of action is still under debate. We have investigated both the role of tryptic fragments of bovine lactoferrin and the mechanism of lactoferrin antiviral effect toward adenovirus infection in HEp-2 cells. The results obtained demonstrated that the anti-adenovirus activity of lactoferrin is mediated by the N-terminal half of the protein as the N-lobe was able to inhibit adenovirus infection, even if at lower extent than undigested lactoferrin, whereas C-lobe was ineffective. The results also showed that the anti-adenovirus action of lactoferrin and of its N-terminal peptide lactoferricin took place on virus attachment to cell membrane, mainly through competition for common glycosaminoglycan receptors. The data provide evidence that the anti-adenovirus activity of lactoferrin is mediated mainly by the cluster of positive charges at the N-terminus of whole molecule and that the N-terminal peptide lactoferricin alone is sufficient to prevent infection.  相似文献   
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BACKGROUND: Coconut (Cocos nucifera) is a monocotyledonous plant of the Arecaceae family. Allergy to coconut is infrequent, with only 5 cases reported so far in the medical literature. OBJECTIVE: To identify coconut allergens in 2 patients allergic to this food. METHODS: We describe 2 patients allergic to coconut: an adult pollen-allergic patient monosensitized to coconut who presented with severe oropharyngeal symptoms and a child with a previous allergy to walnut, not allergic to pollen, who developed anaphylaxis on coconut ingestion. Both patients had positive skin prick test results and serum specific IgE (CAP) to coconut. IgE sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting was performed to identify the allergens involved, and a strong IgE binding band detected in both patients was further analyzed by matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy (MALDI-TOF MS). Stability to pepsin digestion of the coconut extract and its cross-reactivity with tree nuts were studied. RESULTS: An immunoblot showed an almost identical profile of IgE binding proteins in the coconut extract in both patients who reacted strongly to a band of approximately 29 kDa. The peptide analysis by MALDI-TOF MS of this band obtained the sequence GHGKREDPEKR. The protein with the highest correlation with this peptide was found to be a 7S globulin from Elaeis guineensis, another oil palm species also belonging to the Arecaceae family. The 29-kDa band was digested by pepsin in less than 1 minute. Cross-reactivity among coconut, walnut, and hazelnut was demonstrated by CAP inhibition in patient 2. CONCLUSION: We have identified a 7S storage protein as a novel coconut allergen.  相似文献   
59.
At least 1 in 1000 males lacks part of the long arm of the Y chromosome. This chromosomal aberration is often associated with short stature and infertility. Deletion mapping and genotype-phenotype analysis have previously defined two non-overlapping critical regions for growth controlling gene(s), GCY(s), on the euchromatic portion of the Y chromosome long arm. These initial mapping assignments were based on the analysis of patients carrying a pure 46,XYq- karyotype as defined by classical cytogenetic karyotyping. Four genes have been assigned to the distal one of the two critical regions. To determine whether one or both of these two critical regions harbours GCY and whether one of the four genes assigned to the distal region is involved in determination of stature, nine adult patients with Yq chromosomal abnormalities were studied in detail. By PCR and FISH analysis, we showed that all patients with a previously defined pure 46,XYq- karyotype are actually mosaics with cells containing an idic(Y) or ring(Y) chromosome in association with 45,X0 cells. This leads us to conclude that (1) FISH is an absolute prerequisite for the correct identification of Y chromosomal rearrangements and (2) only patients with interstitial Y deletions are reliable predictors for the physical location of stature gene(s) on Yq. Our molecular analyses of chromosomes from patients with interstitial Yq deletions finally establishes the proximal interval between markers DYZ3 and DYS11 as the only GCY critical interval. No functional gene has so far been identified in this region adjacent to the centromere.  相似文献   
60.
PURPOSE: To examine satisfaction with access to health care in two populations, one with HIV and one with TB, and examine the effect of having a regular doctor and sociodemographic characteristics. DESIGN: Cross-Sectional survey. PATIENTS: A sample of HIV inpatients hospitalized at seven Los Angeles sites (N = 217) and TB outpatients chosen randomly from the Los Angeles County TB Registry Census (N = 313). ANALYSIS: We performed bivariate and multivariate regression analyses of satisfaction with access to care on gender, race/ethnicity, age, education, income, insurance, and having a regular doctor. MAIN OUTCOME MEASURES: A six-item scale of satisfaction with access to care (range 0-100; Cronbach's alpha 0.87). RESULTS: The mean satisfaction with access score for the HIV sample was significantly lower than the TB sample (53.5 vs. 61.2, p<0.001). The HIV sample multivariate analysis (including all the variables) showed that increasing age (p<0.021 and having a regular doctor (p<0.002) were associated with better access, and that low income (p<0.005) was associated with poor access. In the TB sample analysis, only increasing age was associated with better satisfaction with access to care (p< 0.01). CONCLUSION: HIV patients receiving care in the private sector reported less satisfaction with access to care compared to TB patients receiving care in the public health sector. The traditional factors of socio-economic status and having a regular doctor were associated with satisfaction with access-to-care in the HIV sample but not the TB sample. Our findings suggest that certain characteristics of the TB public health programs may explain these differences and suggests that, perhaps, the existence of a similar public health program for vulnerable low-income populations with HIV would improve their satisfaction with access, as well.  相似文献   
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