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71.
Histological, immunohistochemical, and electron microscopic evidence of an extracellular, or ghost Pick body has been found in the granular cell layer and, rarely, in the pyramidal cell layer of the hippocampus of an autopsy case of Pick's disease. The ghost Pick body appeared as a blurred, weak argyrophilic mass in the neuropil, and it was composed of accumulated fibrillary structures, 13 nm in diameter, intermingled with glial filament bundles. These ghost Pick bodies did not react with anti-tau and antiubiquitin antibodies, but did react weakly with antiglial fibrillary acidic protein antibody, whereas intracytoplasmic Pick bodies were strongly immunolabeled with anti-tau but only weakly with anti-ubiquitin anti-bodies. These results suggest that the Pick body is discharged into the neuropil after destruction of the mother neuron, loses its immunoreactivity to certain tau and ubiquitin antibodies during this process (thereby inducing a glial reaction) and remains in the neuropil as a ghost Pick body.  相似文献   
72.
We present the new computerized Human Brain Atlas (HBA) for anatomical and functional mapping studies of the human brain. The HBA is based on many high-resolution magnetic resonance images of normal subjects and provides continuous updating of the mean shape and position of anatomical structures of the human brain. The structures are transformable by linear and nonlinear global and local transformations applied anywhere in 3-D pictures to fit the anatomical structures of individual brains, which, by reformatting, are transformed into a high-resolution standard anatomical format. The power of the HBA to reduce anatomical variations was evaluated on a randomized selection of anatomical landmarks in brains of 27 young normal male volunteers who were different from those on whom the standard brain was selected. The HBA, even when based only on standard brain surface and central structures, reduced interindividual anatomical variance to the level of the variance in structure position between the right and left hemisphere in individual brains. © 1994 Wiley-Liss, Inc.  相似文献   
73.
BACKGROUND: Allergic inflammation is characterized by the influx and activation of eosinophils. Cytokines generated by both resident and infiltrating cells are responsible for the initiation and maintenance of this pathogenesis. This study focuses on allergen-induced activation of eosinophil NF-kappaB and generation of granulocyte macrophage-colony stimulating factor (GM-CSF), TNF-alpha, and IL-8. METHODS: Peripheral blood eosinophils were enriched to >99.9% by Percoll gradient sedimentation and negative magnetic affinity chromatography. NF-kappaB activation by 10 microg/mL house dust mite (HDM) extract was demonstrated immunocytochemically using a monoclonal antibody against the active form of NF-kappaB (NF-kappaBa). The authenticity of NF-kappaB was confirmed by Western blot. Cytokine production was assessed both by immuno-staining of eosinophils and by assay of cytokines in the cell supernatant. RESULTS: Activation of peripheral blood eosinophils from atopic, but not non-atopic, donors induced activation of NF-kappaB, which peaked at 4 h and was accompanied by a decline in IkappaB-alpha. The activation of authentic NF-kappaB was confirmed in gel shift assays. Supershift assays showed p65 to be the major subunit of eosinophil NF-kappaB. Immunofluorescent confocal microscopy demonstrated localization of NF-kappaBa to the nucleus. Following activation, cytokine immunoreactivity was seen in a fraction of the eosinophils and cytokines were released into the supernatant. The NF-kappaB inhibitors, calpain inhibitor 1 (10 microm), pentoxifylline (0.5 mm), pyrrolidine dithiocarbamate (PDTC, 10 microm) or gliotoxin (1 pg/mL) reduced the generation of GM-CSF, TNF-alpha and IL-8 in parallel with their inhibition of NF-kappaB. CONCLUSIONS: HDM allergen activates human eosinophil NF-kappaB leading to the production of the cytokines GM-CSF, TNF-alpha and IL-8. We speculate that a role for eosinophil NF-kappaB-dependent cytokines is to act as an autocrine loop augmenting the survival of eosinophils in vivo.  相似文献   
74.
Recent changes in UK law have allowed UK-based optometrists to sell and supply fusidic acid viscous eyedrops, providing it is in the course of their professional activity and in an emergency. Alternatively, the optometrist may access fusidic acid viscous eyedrops, for a named patient, using a written order supplied to a pharmacy. This review provides details of the legal background to these changes, examines the common causes of a bacterial conjunctivitis, examines the mechanism of action of this narrow spectrum antibiotic as a bacteriostatic agent, reviews the susceptibility of common ocular isolates of bacteria to the drug and presents details of the expected pharmacokinetics of the viscous eyedrops. From this perspective, a systematic review is provided of the clinical studies which have investigated the use of fusidic acid viscous eyedrops and their outcome. The indicated use is generally for the treatment of bacterial conjunctivitis and/or blepharoconjunctivitis, especially that caused by Staphylococcus, but not Streptococcus or Haemophilus sp. (more likely associated with concurrent nasopharyngeal infections). The usual regimen for use is twice daily for 5-10 days, depending on severity, and can initially be used more intensively (four times per day). It may also be used for the management of corneal and conjunctival abrasions and foreign body injuries, or some cases of chronic blepharitis.  相似文献   
75.
Objective: To evaluate the role of gastrointestinal (GI) endoscopy in human immunodeficiency virus (HIV)‐infected children with GI problems. Methods: From 1998 to 2002, we retrospectively reviewed all cases of HIV‐infected children presenting with GI problems in which an upper or lower GI endoscopy was indicated. The initial diagnostic endoscopic examination and any repeat endoscopic session leading to a new diagnosis were used in the data analysis. Tissue biopsies were obtained from all abnormal lesions and representative sites of normal‐appearancing GI mucosa. Results: Fourteen patients (median age: 22.5 months) underwent 23 sessions of GI endoscopy, including 10 esophagogastroduodenoscopy, nine colonoscopy and four flexible sigmoidoscopy. Chronic diarrhea was the most common indication, followed by lower GI bleeding, abdominal/retrosternal pain, dysphagia/odynophagia, and upper GI bleeding. Gross endoscopic abnormalities were observed in 78.3%; whereas histological inflammation and opportunistic pathogens were identified in 87% and 43.5%, respectively. Cytomegalovirus was the most common identified pathogen. Abnormal gross findings were significantly associated with histological inflammation and identification of pathogens (P = 0.006 and 0.046, respectively). Specific changes in medical management were made in 50% of cases as a result of endoscopic investigation. Conclusion: If non‐invasive investigations for HIV‐infected children with GI symptoms fail to establish a diagnosis, gastrointestinal endoscopy should be performed and often yields a positive result leading to changes in medical management.  相似文献   
76.
AIMS: The glutamate decarboxylase gene (GAD2) encodes GAD65, an enzyme catalysing the production of the gamma-aminobutyric acid (GABA) which interacts with neuropeptide Y to stimulate food intake. It has been suggested that in pancreatic islets, GABA serves as a functional regulator of pancreatic hormone release. Conflicting results have been reported concerning the potential impact of GAD2 variation on estimates of energy metabolism. The aim of this study was to elucidate potential associations between the GAD2-243A-->G polymorphism and levels of body mass index (BMI) and estimates of glycaemia. METHODS: Using high-throughput chip-based matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, the GAD2-243A-->G (rs2236418) polymorphism was genotyped in a population-based sample (Inter99) of 5857 middle-aged, unrelated Danish White subjects. RESULTS: The G-allele was associated with modestly lower BMI (P = 0.01). In a case-control study of obesity, the G-allele frequency in 2582 participants with BMI < 25 kg/m2 was 19.5% (18.4-20.6) compared with 17.1% (15.5-18.8) in 968 participants having BMI > or = 30 kg/m2 (P = 0.03), odds ratio 0.9 (0.7-1.0). Of the 5857 subjects, GG carriers had lower fasting plasma glucose levels (mmol/l) [AA (n = 3859) 5.6 +/- 0.8; AG (n = 1792) 5.5 +/- 0.8; GG (n = 206) 5.5 +/- 0.8, P = 0.008] and lower 30-min oral glucose tolerance test (OGTT)-related plasma glucose levels (AA 8.7 +/- 1.9; AG 8.6 +/- 1.9; GG 8.6 +/- 2.0, P = 0.04), adjusted for sex, age and BMI. Analysing subjects who were both normoglycaemic and glucose tolerant (n = 4431) GG carriers still had lower fasting plasma glucose concentrations: AA (n = 2895) 5.3 +/- 0.4; AG (n = 1383) 5.3 +/- 0.4; GG (n = 153) 5.2 +/- 0.4 (P = 9.10(-5)). CONCLUSION: The present study suggests that the GAD2-243A-->G polymorphism in a population of middle-aged White people associates with a modest reduction in BMI and fasting and OGTT-related plasma glucose levels.  相似文献   
77.
78.
AIMS: Overweight is common during late puberty in female patients with Type 1 diabetes. The aim of this study was to examine the change in body composition from late puberty to early adulthood in such female patients in comparison with age-matched control subjects. METHODS: Eighteen females with Type 1 diabetes and 19 healthy female control subjects were recruited for a case-control study at the age of 16-19 years (baseline). Six years later, 16 of the diabetic females and 17 of the control subjects were re-examined (follow-up). Body composition was assessed by dual energy X-ray absorptiometry. RESULTS: Body mass index (BMI) and fat mass index (total fat mass/height2) were significantly higher at baseline in the diabetic patients than in the control subjects (26.4 +/- 2.6 vs. 23.9 +/- 3.7 kg/m2, P < 0.05, and 10.0 +/- 2.4 vs. 8.0 +/- 2.8 kg/m2, P = 0.04, respectively). At follow-up, these parameters still tended to be higher in the diabetic group (27.8 +/- 4.9 vs. 24.6 +/- 5.7 kg/m2, P = 0.09, and 11.8 +/- 5.6 vs. 8.7 +/- 4.9 kg/m2, P = 0.05, respectively). BMI at baseline was strongly correlated to BMI at follow-up in both diabetic patients (r = 0.60; P < 0.05) and control subjects (r = 0.83; P < 0.01). CONCLUSIONS: Increased fat mass in pubertal girls with Type 1 diabetes seems to persist in young adulthood. This study emphasizes the need for new strategies to prevent the development of overweight during puberty in diabetic girls.  相似文献   
79.
Although only recently introduced, chemically-modified hyaluronic acid dermal fillers have gained widespread acceptance as “redefining” dermal fillers in the fields of dermatology and cosmetic facial surgery. Although hyaluronic acid-based dermal fillers have a low overall incidence of long term side effects, occasional adverse outcomes, ranging from chronic lymphoplasmacytic inflammatory reactions to classic foreign body-type granulomatous reactions have been documented. These long-term adverse events are reviewed.  相似文献   
80.
Bronchiolitis obliterans syndrome (BOS) is the limiting factor to long-term survival after lung transplantation. Previous studies suggested respiratory viral tract infections are associated with the development of BOS. To identify the impact of virus detection in bronchoalveolar lavage (BAL) fluid, we analyzed BAL samples from 87 consecutive lung transplant recipients for human herpesvirus (HHV)-6, Epstein-Barr virus, Herpes simplex virus 1/2, Cytomegalovirus, respiratory syncytical virus and adenovirus by PCR. Acute rejection, BOS and death were recorded for a mean follow-up time of 3.27 +/- 0.47 years. Results of PCR analysis and other potential risk factors were entered into a Cox regression analysis of BOS predictors and death. Only acute rejection was a distinct risk factor for BOS of all stages, death and death from BOS. HHV-6 was detected in 20 patients. Univariate and multivariate analysis revealed that HHV-6 was associated with an increased risk to develop BOS > orb = stage 1 and death, separate from the risk attributable to acute rejection. Identification of HHV-6 DNA in BAL fluid is a potential risk factor for BOS. Our results warrant further studies to elucidate a possible causal link between HHV-6 and BOS.  相似文献   
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