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21.
22.
Interleukin-1 beta (IL-1beta) exerts a range of inflammatory and immunomodulatory activities that are important in host defense and autoimmune response. The IL-1beta gene, located on chromosome 2 (2q13), is polymorphic. The influence of its polymorphism on 355 patients with autoimmune rheumatic diseases was examined. To this effect, 172 patients with rheumatoid arthritis (RA), 114 with systemic lupus erythematosus (SLE), and 69 with primary Sjogren's syndrome (pSS) were studied. The control group consisted of 392 matched healthy individuals. Genotyping of IL-1beta single-nucleotide polymorphisms (SNPs) at positions -511 (C/T) and + 3953 (C/T) was performed by the polymerase chain reaction-restriction fragment length polymorphism technique. In addition, levels of IL-1beta were measured by immunoassay in supernatants of lipopolysaccharide (LPS)-stimulated and nonstimulated peripheral blood monocytes (PBM) obtained from 19 homozygous individuals for the three most common IL-1beta likely haplotypes, all belonging to the control group. Allele + 3953T was protective for SLE (odds ratio (OR) = 0.57, 95% confidence intervals (CI) = 0.34-0.88, P = 0.01) as was the haplotype -511C + 3953T (OR = 0.43, 95%CI = 0.25-0.74, pc = 0.006). The latter was associated with a lower LPS-stimulated-PBM IL-1beta secretion. Results suggest that IL-1beta polymorphism influences the susceptibility to acquire SLE in our population. The protective association might be explained by the observed inhibitory effect of IL-1beta + 3953T allele on the secretion of IL-1beta under inflammatory circumstances. 相似文献
23.
Marques da Silva SH Queiroz-Telles F Colombo AL Blotta MH Lopes JD Pires De Camargo Z 《Journal of clinical microbiology》2004,42(6):2419-2424
Paracoccidioidomycosis (PCM) is a systemic fungal disease that is particularly important among individuals living and working in rural areas of endemicity in Latin America. Detection of anti-Paracoccidioides brasiliensis antibodies is of limited value due to false-negative results. Detection of P. brasiliensis-gp43 circulating antigen is a practical approach for a specific diagnosis of the disease. In a previous study we described an inhibition enzyme-linked immunosorbent assay able to detect the 43-kDa P. brasiliensis antigen in sera of 100% of patients with the acute form of PCM and in 95.31 and 100% of patients with the chronic multifocal and unifocal forms of PCM. To investigate its potential application for the follow-up of PCM patients during treatment, antigen levels were monitored at regular intervals for up 8 to 12 months in serum samples from 23 patients. The results showed that treatment with itraconazole resulted in decreasing levels of circulating gp43 that were correlated with the reduction of anti-gp43 antibodies. It was also observed that by the end of 12 months of treatment gp43 levels were <5 microg/ml in all patients. 相似文献
24.
D Chatel Y Martin-Bouyer C Acar H Bouchoucha JL Sableyrolles V Jebara JC Chachques A Carpentier 《Surgical and radiologic anatomy : SRA》1993,15(4):341-348
Summary The anatomic constraints imposed on a total artificial heart (TAH) require specific anatomic studies. A thoracic anatomic study was performed with a scanning device equipped with three-dimensional (3-D) reconstruction software on 15 male patients, between the ages of 41 to 63 years (52 ± 6 years). All were candidates for heart transplantation. The 3-D reconstructions of the cardiovascular structures obtained from surgical anatomy data specific to TAH implantation allowed a volumetric measurement of these structures. A modeling diagram of these structures permitted reproducible quantitative measurements of the 35 geometrical parameters which characterized shape, orientation, and position of these structures within the thorax. Most of the measured parameters were characterized by low variability (coefficient of variation from 10 to 25%).
Modélisation tridimensionnelle de l'anatomie du cur et des gros vaisseaux
Résumé Les contraintes anatomiques imposées au cur artificiel total (CAT) nécessitent des études anatomiques spécifiques. Une étude anatomique thoracique a été réalisée avec un scanner doté d'un logiciel de reconstruction tridimensionnelle (3-D) chez 15 patients, tous de sexe masculin, agés de 41 à 63 ans (52 ± 6 ans), et candidats à une transplantation cardiaque. Les reconstructions 3-D des structures cardio-vasculaires réalisées selon les données de l'anatomie chirurgicale propre à l'implantation du CAT ont permis la mesure volumétrique de ces structures. Un schéma de modélisation de ces structures a permis des mesures quantitatives reproductibles de 35 paramètres géométriques caractéristiques de la forme, de l'orientation, de la position de ces structures dans le thorax. Les résultats de ces mesures ont pu être exprimés en termes statistiques. La plupart des paramètres mesurés étaient caractérisés par une faible variabilité (coefficients de variations de 10 à 25%).相似文献
25.
Inhibitory effect of ethacrynic acid on chloride permeability 总被引:1,自引:0,他引:1
26.
Gontijo AM Marcondes JP Elias FN de Oliveira ML de Lima RO Salvadori DM de Camargo JL 《Environmental and molecular mutagenesis》2002,40(3):190-199
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells. 相似文献
27.
Frataxin is reduced in Friedreich ataxia patients and is associated with mitochondrial membranes 总被引:17,自引:8,他引:17
Campuzano V; Montermini L; Lutz Y; Cova L; Hindelang C; Jiralerspong S; Trottier Y; Kish SJ; Faucheux B; Trouillas P; Authier FJ; Durr A; Mandel JL; Vescovi A; Pandolfo M; Koenig M 《Human molecular genetics》1997,6(11):1771-1780
Friedreich ataxia is a progressive neurodegenerative disorder caused by
loss of function mutations in the frataxin gene. In order to unravel
frataxin function we developed monoclonal antibodies raised against
different regions of the protein. These antibodies detect a processed 18
kDa protein in various human and mouse tissues and cell lines that is
severely reduced in Friedreich ataxia patients. By immunocytofluorescence
and immunocytoelectron microscopy we show that frataxin is located in
mitochondria, associated with the mitochondrial membranes and crests.
Analysis of cellular localization of various truncated forms of frataxin
expressed in cultured cells and evidence of removal of an N-terminal
epitope during protein maturation demonstrated that the mitochondrial
targetting sequence is encoded by the first 20 amino acids. Given the
shared clinical features between Friedreich ataxia, vitamin E deficiency
and some mitochondriopathies, our data suggest that a reduction in frataxin
results in oxidative damage.
相似文献
28.
Dongari-Bagtzoglou AI; Warren WD; Berton MT; Ebersole JL 《International immunology》1997,9(9):1233-1241
CD40, a member of the tumor necrosis factor-alpha receptor family, is
constitutively expressed by cells of hematopoietic and non- hematopoietic
origin, including fibroblasts. Signaling through this receptor molecule
regulates inflammatory cytokine secretion by many cell types. Based on the
recently described cytokine secretory heterogeneity of fibroblast cell
subsets, we hypothesized that secretion of inflammatory cytokines by
gingival fibroblast cultures may be dictated by the existence of
differential proportions of cytokine- secreting subpopulations which
express high levels of CD40. After examining a large number of gingival
fibroblast (GF) cultures we find that the frequency of IL-6- and
IL-8-secreting cells mirrors the frequency of cells expressing high levels
of CD40 in these cultures. In addition, we demonstrate a direct functional
relationship between CD40 expression and IL-6 or IL-8 secretion by showing
that ligation of this molecule on GF, and CD40+ fibroblast subsets in
particular, up- regulates secretion of these cytokines in vitro.
相似文献
29.
V Júnior Haddad H A Miot L D Bartoli A de Chiara Cardoso R M Pires de Camargo 《Medical mycology》2002,40(4):425-427
Localized lymphatic sporotrichosis generally develops after the fungus Sporothrix schenckii is traumatically introduced into skin or mucosa by contaminated plant material. An 18-year-old male fisherman was injured by spines of the dorsal fin of a fish on the left third finger. The lesion became ulcerated, edematous and suppurative and did not respond to tetracycline and cephalexin. Fifteen days after the accident, a nodular lymphangitic pattern of swelling was observed. Histopathological findings and an intradermal test were suggestive of sporotrichosis and mycological cultures confirmed the diagnosis. The lesions resolved after oral treatment with potassium iodide. Sporotrichosis is a common subcutaneous mycosis in Brazil, and there is a previous report in the literature of this disease being acquired via trauma involving fish spines. 相似文献
30.
The aim of this study was to evaluate the effect of ten pesticides on Paracoccidioides brasiliensis, and thereby to investigate the possible association between these data and the difficulty in isolating P. brasiliensis from agricultural soil. Six fungicides (Alto 100, Benlate, Captan, Dithane, Plantacol, Rovral), two herbicides (Pivot, Roundup) and two insecticides (Azodrin and Curacron) were evaluated. Five P. brasiliensis isolates from the environment (labelled group 'N,' for 'nature') and five isolates from patients (group 'P'), were grown on Sabouraud's dextrose agar, at 35 degrees C, with ten different concentrations of each pesticide. The dose of pesticide that causes 50% growth inhibition (ED50) was calculated for each isolate. All pesticides assayed inhibited P. brasiliensis in a dose-dependent manner, and great variability among ED50 values was observed in isolates from both groups. No statistically significant difference was observed between averages of ED50 from groups N and P, except with Alto 100. The inhibitory effect of pesticides on P. brasiliensis suggests that they can interfere with attempts to isolate P. brasiliensis from soil, where tonnes of pesticides are applied over large areas planted with various crops. 相似文献