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排序方式: 共有6213条查询结果,搜索用时 15 毫秒
41.
Kurz T Strauch K Heinzmann A Braun S Jung M Rüschendorf F Moffatt MF Cookson WO Inacio F Ruffilli A Nordskov-Hansen G Peltre G Forster J Kuehr J Reis A Wienker TF Deichmann KA 《The Journal of allergy and clinical immunology》2000,106(5):925-932
BACKGROUND: Sensitization to mite allergens represents a prominent feature of atopy and an important predictor of bronchial asthma. OBJECTIVE: It was the intention of this study to define genetic loci linked to mite sensitization because these could represent the genetic basis of the important atopic component of asthma. METHODS: We studied a multiethnic white population of 99 families, including 224 sib pairs sensitized to Dermatophagoides pteronyssinus. A genome-wide candidate-region search was performed that covered potential asthma and atopy regions. RESULTS: As for nonparametric linkage (NPL) analysis, 14 of the candidate regions showed evidence for linkage (NPL > 2.0), and 4 of them showed prominent linkage (NPL > 3.0). However, there were substantial ethnic differences. Maximizing the LOD score analysis identified candidate regions with suspected dominant and recessive mode of inheritance. Furthermore, genetic imprinting models provided significant evidence for linkage in the 8p23 region and revealed potential maternal imprinting. The regions found are distinct to those in asthma searches that have been found to be linked to asthma, as well to other inflammatory diseases. In addition, we could not find linkage to the HLA region. By different cutoff points of the phenotype definition, the IL cluster showed evidence of being linked to the degree of sensitization rather than to sensitization per se. CONCLUSION: The results indicate that the genetic basis of the atopic component of asthma is different from that of the inflammatory component. Furthermore, it seems reasonable to assume that specific sensitizations are influenced by distinct genetic variants leading to their initiation versus those leading to their enhancement. 相似文献
42.
Angèle S Jones C Reis Filho JS Fulford LG Treilleux I Lakhani SR Hall J 《Journal of clinical pathology》2004,57(11):1179-1184
AIMS: To analyse the expression of proteins involved in DNA double strand break detection and repair in the luminal and myoepithelial compartments of benign breast lesions and malignant breast tumours with myoepithelial differentiation. METHODS: Expression of the ataxia telangiectasia (ATM) and p53 proteins was immunohistochemically evaluated in 18 benign and malignant myoepithelial tumours of the breast. Fifteen benign breast lesions with prominent myoepithelial compartment were also evaluated for these proteins, in addition to those in the MRE11-Rad50-NBS1 (MRN) complex, and the expression profiles were compared with those seen in eight independent non-cancer (normal breast) samples and in the surrounding normal tissues of the benign and malignant tumours examined. RESULTS: ATM expression was higher in the myoepithelial compartment of three of 15 benign breast lesions and lower in the luminal compartment of eight of these lesions compared with that found in the corresponding normal tissue compartments. Malignant myoepithelial tumours overexpressed ATM in one of 18 cases. p53 was consistently negative in benign lesions and was overexpressed in eight of 18 malignant tumours. In benign breast lesions, expression of the MRN complex was significantly more reduced in myoepithelial cells (up to 73%) than in luminal cells (up to 40%) (p=0.0005). CONCLUSIONS: Malignant myoepithelial tumours rarely overexpress ATM but are frequently positive for p53. In benign breast lesions, expression of the MRN complex was more frequently reduced in the myoepithelial than in the luminal epithelial compartment, suggesting different DNA repair capabilities in these two cell types. 相似文献
43.
Milan Macek Jr. Milan Macek Manfred Stuhrmann Eduard Kulovany Marie Dolanská Frantiek Koukolík Ingolf Boehm Jana Hronková Zdeka Jeková Magdalena Paulová Hana Martanová Jií Zach ré Reis Karl Sperling Jörg Schmidtke 《Clinical genetics》1991,39(3):219-222
The suspicion of prenatal meconium ileus syndrome was raised in a pregnancy in a family with no history of cystic fibrosis because of significantly higher maternal serum alpha-fetoprotein in the 16th and 19th week of gestation, dispersed areas with increased echogenity in the fetal abdomen, slight fetal ascites in the 24th-25th weeks of gestation, decreased amniotic fluid gamma-glutamyltranspeptidase (GGT) activity and alpha-fetoprotein level in the 25th-26th weeks, and normal 46,XY karotype of the fetus. The detection of a homozygous deltaF508 cystic fibrosis transmembrane regulator (CFTR) gene mutation, by means of PCR from a small amount of white blood cells and urine sediment cells, substantiated the diagnosis of cystic fibrosis in a prematurely delivered boy in the 28th week of gestation. The repeated sweat test was unsuccessful. The autopsy examination confirmed the diagnosis of cystic fibrosis. Fetal meconium ileus syndrome was complicated by peritonitis and by formation of a meconium pseudocyst. Direct PCR typing improves postnatal diagnostic possibilities in the early neonatal period in prematurely delivered babies when the sweat test is difficult to perform. 相似文献
44.
Dendritic cells (DCs) can be activated directly by triggering of receptors for pathogens or, indirectly, by exposure to inflammatory signals. It remains unclear, however, whether the two pathways result in qualitatively similar DCs or lead to equivalent adaptive immune responses. Here we report that indirect activation by inflammatory mediators generated DCs that supported CD4(+) T cell clonal expansion but failed to direct T helper cell differentiation. In contrast, exposure to pathogen components resulted in fully activated DCs that promoted T helper responses. These results indicate that inflammation cannot substitute for contact with pathogen components in DC activation and suggest that the function of pattern recognition by DCs is to couple the quality of the adaptive immune response to the nature of the pathogen. 相似文献
45.
Transition metal complexes containing vanadium IV have been shown to
modulate the cellular redox potential and catalyse the generation of
reactive oxygen intermediates (ROI). Since sperm function is exquisitely
susceptible to ROI, we examined the effects of stable chelate complexes of
vanadocenes on human sperm motility. We synthesized seven structurally
distinct chelate complexes of bis(cyclopentadienyl)vanadium(IV) with
bidentate ligands [i.e. vanadocene acetylacetonato monotriflate (VDacac),
vanadocene hexafluoro acetylacetonato monotriflate (VDHfacac), vanadocene
N-phenyl benzohydroxamato monotriflate (VDPH), vanadocene acethydroxamato
monotriflate (VDH), vanadocene catecholate (VDCAT), vanadocene bipyridino
ditriflate (VDBPY), and vanadocene dithiocarbamate monotriflate (VDDTC)],
and evaluated their spermicidal activity using computer-assisted sperm
analysis (CASA; Hamilton-Thorne). All seven chelate complexes of vanadocene
elicited potent spermicidal activity at micromolar concentrations (EC50
values: 3.9-106 microM) without affecting the sperm acrosome integrity. The
catecholate and acetylacetonate complexes of vanadocene were the most
active and the bipyridyl complex the least active with an order of efficacy
VDCAT > VDacac > VDDTC > VDPH > VDH > VDHfacac > VDBPY.
The spermicidal activity of chelate complexes of vanadocenes was rapid and
irreversible since the treated spermatozoa underwent apoptosis, as
determined by the flow cytometric analysis of mitochondrial membrane
potential, surface annexin V binding assay, in-situ nick-end labelling of
sperm nuclei, and confocal laser scanning microscopy. These results provide
unprecedented evidence that chelate complexes of vanadocene with bidentate
ligands have spermicidal and apoptosis inducing properties. These
vanadocene complexes, especially VDacac, may be useful as contraceptive
agents.
相似文献
46.
Boss JH Misselevich I Peskin B Zinman C Levin D Norman D Reis DN 《Journal of comparative pathology》2003,129(2-3):235-239
The femoral heads of 15 rats were studied histologically 3 months after the induction of ischaemic necrosis by incising the cervical periosteum and cutting the ligamentum teres. The epiphyses consisted of immature disorganized subchondral and trabecular bone. The inter-trabecular spaces contained fibrous or haematopoietic tissue. Residual necrotic bone was rare. There was marked osteoblastic and osteoclastic activity. The articular aspect of the heads showed a spectrum of changes, ranging from cartilaginous degeneration with fibrillation and loss of glycosaminoglycans to an eburnated and polished bony surface. In seven rats, transphyseal bridges connected the epiphyseal and metaphyseal bony trabeculae to each other. It is suggested that the postnecrotic reparative processes, including the resorption of the necrotic debris and its replacement by newly formed, weak bone, led to an osteoarthritis-like disorder. This healing pattern of the necrotic femoral head was reminiscent of the progressive remodelling that occurs in rings in femoral capital osteonecrosis of adult human patients and in Perthes's disease of children. 相似文献
47.
Rocha-Rodrigues DB Paschoini G Pereira SA dos Reis MA Teixeira Vde P Rodrigues Júnior V 《Clinical and diagnostic laboratory immunology》2003,10(5):741-743
Endemic pemphigus foliaceus (EPF) is an autoimmune disease characterized by blister formation with a loss of cohesion and infiltration of inflammatory cells. We observed that supernatants of peripheral blood mononuclear cells from patients produced significantly more interleukin-1beta (IL-1beta) than those from stimulated healthy controls. Furthermore, a Th2 bias was observed in EPF patients when the IL-5/gamma interferon ratio was analyzed. These results indicate that cells from pemphigus patients react with a vigorous proinflammatory response. 相似文献
48.
Lima AP dos Reis FC Serveau C Lalmanach G Juliano L Ménard R Vernet T Thomas DY Storer AC Scharfstein J 《Molecular and biochemical parasitology》2001,114(1):41-52
Cysteine-proteinases from parasitic protozoa have been recently characterized as factors of virulence and pathogenicity in several human and veterinary diseases. In Chagas' disease, the chronic infection caused by Trypanosoma cruzi, structure-functional studies on cysteine proteases were thus far limited to the parasite's major isoform, a cathepsin L-like lysosomal protease designated as cruzipain, cruzain or GP57/51. Encoded by a large gene family, cruzipain is efficiently targeted by synthetic inhibitors, which prevent parasite intracellular growth and differentiation. We have previously demonstrated that the multicopy cruzipain gene family includes polymorphic sequences, which could encode functionally different isoforms. We report here a comparative kinetic study between cruzain, the archetype of the cruzipain family, and an isoform, termed cruzipain 2, which is expressed preferentially by the mammalian stages of T. cruzi. Heterologous expression of the catalytic domain of cruzipain 2 in Saccharomyces cerevisae yielded an enzyme that differs markedly from cruzain with respect to pH stability, substrate specificity and sensitivity to inhibition by natural and synthetic inhibitors of cysteine proteases. We suggest that the structural-functional diversification imparted by genetic polymorphism of cruzipain genes may have contributed to T. cruzi adaptation to vertebrate hosts. 相似文献
49.
IMPs, VIMs and SPMs: the diversity of metallo-β-lactamases produced by carbapenem-resistant Pseudomonas aeruginosa in a Brazilian hospital 总被引:3,自引:0,他引:3
Pseudomonas aeruginosa isolates (n=183), collected from bacteraemic patients hospitalised in Sao Paulo Hospital (Brazil) during 2000-2001, were screened for susceptibility to antimicrobial agents. The polymyxins were the most active compounds (100% susceptibility), followed by amikacin and cefepime (59.0%), meropenem (57.4%), and imipenem and gentamicin (55.2%). Imipenem-resistant isolates were ribotyped and screened for production of metallo-beta-lactamases (MBLs) by PCR with primers for bla(IMP), bla(VIM) and bla(SPM). MBL production was detected in 36 isolates (19.7% of the entire collection; 43.9% of the imipenem-resistant isolates) and the MBLs included SPM-1-like (55.6%), VIM-2-like (30.6%) and IMP-1-like (8.3%) enzymes. 相似文献
50.