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71.
Dominique Bonneau Isabelle Winter-Fuseau Marie-No?lle Loiseau Patrizia Amati Michel Berthier Denis Oriot Carole Beaumont 《Journal of medical genetics》1995,32(10):778-779
This paper reports the cosegregation in a three generation pedigree of dominantly inherited cataract with an abnormally high level of serum ferritin. In this family, circulating L ferritin was raised in all subjects affected by cataract independently of iron overload. We suggest that a disorder of ferritin metabolism could be a new genetic disorder leading to lens opacity. Cataract-hyperferritaemia syndrome could also be a new contiguous gene syndrome involving the L ferritin gene and the gene coding for the lens membrane protein (MP19), which both map to the same region of chromosome 19q. 相似文献
72.
A 1463 gene cattle-human comparative map with anchor points defined by human genome sequence coordinates 总被引:5,自引:0,他引:5 下载免费PDF全文
Everts-van der Wind A Kata SR Band MR Rebeiz M Larkin DM Everts RE Green CA Liu L Natarajan S Goldammer T Lee JH McKay S Womack JE Lewin HA 《Genome research》2004,14(7):1424-1437
A second-generation 5000 rad radiation hybrid (RH) map of the cattle genome was constructed primarily using cattle ESTs that were targeted to gaps in the existing cattle-human comparative map, as well as to sparsely populated map intervals. A total of 870 targeted markers were added, bringing the number of markers mapped on the RH(5000) panel to 1913. Of these, 1463 have significant BLASTN hits (E < e(-5)) against the human genome sequence. A cattle-human comparative map was created using human genome sequence coordinates of the paired orthologs. One-hundred and ninety-five conserved segments (defined by two or more genes) were identified between the cattle and human genomes, of which 31 are newly discovered and 34 were extended singletons on the first-generation map. The new map represents an improvement of 20% genome-wide comparative coverage compared with the first-generation map. Analysis of gene content within human genome regions where there are gaps in the comparative map revealed gaps with both significantly greater and significantly lower gene content. The new, more detailed cattle-human comparative map provides an improved resource for the analysis of mammalian chromosome evolution, the identification of candidate genes for economically important traits, and for proper alignment of sequence contigs on cattle chromosomes. 相似文献
73.
M Denis 《Journal of leukocyte biology》1991,49(4):380-387
An avirulent and a virulent strain of Mycobacterium avium were selected on the basis of their growth patterns in human monocyte-derived macrophages. The virulent 7497 M. avium grew progressively in untreated macrophages, whereas the avirulent LR/149 M. avium was killed to a moderate extent by untreated human macrophages (50% of the original infectious inoculum killed 7 days after infection). We set out to investigate the possibility of modulating these growth patterns by cytokine treatment. Application of tumor necrosis factor (TNF) (100 U/ml) led to macrophages restricting significantly the growth of virulent M. avium 7497 (tenfold decrease at 7 days). TNF was also effective at modulating positively the interaction between avirulent LR/149 M. avium and macrophages inasmuch as TNF-treated cells killed 99% of infecting mycobacteria at 7 days. Granulocyte macrophage-colony stimulating factor (GM-CSF) (100-10,000 U/ml) treatment led to macrophages being as mycobacteriostatic for virulent 7497 M. avium as TNF-alpha-treated cells (i.e., tenfold reduction in growth). Treatment of macrophages with both GM-CSF and TNF-alpha was shown to have additive effects on bacteriostatic activity on M. avium. The mechanism of killing of avirulent M. avium by TNF-alpha was shown to be dependent on the generation of reactive nitrogen intermediates, as seen by inhibition of effector mechanisms by NG-monomethyl-arginine and arginase. Moreover, there was a correlation between NO2- generation and mycobactericidal activity of macrophages. Addition of superoxide dismutase reversed the killing of avirulent M. avium by untreated or TNF-treated macrophages. This abrogation was also apparent in chronic granulomatous disease (CGD) macrophages, which were inefficient at generating reactive oxygen intermediates. Moreover, macrophages from CGD patients killed avirulent M. avium as efficiently as cells from normal individuals. We conclude from these results that 1) GM-CSF and TNF-alpha, alone or in combination, increase effector functions of macrophages against virulent and avirulent strains of M. avium; 2) reactive nitrogen intermediates seem to be involved in this effector mechanism; and 3) superoxide dismutase protected M. avium against macrophage effector function, seemingly by protecting the bacteria against endogenous superoxide anion. The implications of these findings for host resistance to atypical mycobacteria are discussed. 相似文献
74.
Human neutrophils exposed to indomethacin demonstrate an enhanced capacity for superoxide ion (O
2
–
) generation when stimulated with opsonized zymosan. Enhancement is not seen with indomethacin-treated cells exposed to solube oxidative stimuli. To further investigate this phenomenon, O
2
–
generation, chemiluminescence, and phagocytosis were assessed in human neutrophils preincubated with indomethacin. Zymosan-stimulated O
2
–
release was increased from 150 to 300% of controls in neutrophils exposed to 400 g/ml. indomethacin. Enhancement was not reversed by removal of indomethacin from the medium prior to addition of the stimulus and was dose-dependent at drug concentrations of 5 to 400 /ml. Neutrophils exposed to methacin alone also generated more O
2
–
than control cells, although this increment was not sufficient to account for the degree of enhancement seen when indomethacintreated cells were exposed to zymosan. Neutrophil cehmiluminescence induced by zymosan was also increased by exposure to indomethacin, and at a drug concentration of 400 g/ml (1.1 mM), enhancement randed from 253 to 333% of controls. As was observed with O
2
–
generation, chemiluminescence of neutrophils was increased in the presence of indomethacin alone, although, to a degree far less than was seen when drug-treated cells were stimulated with zymosan. Phagocytosis of radiolabeledS. aureus by neutrophils incubated with indomethacin was increased 13±5% over controls (P<0.01,n=5), but was unaltered by incubation of cells with the buffer used to solubilize the drug. The modest degree of enhancement of phagocytosis suggests that increased particle uptake is not the sole mechanism of oxidative enhancement. The data are in keeping with the hypothesis that indomethacin has a direct effect on the neutrophil plasma membrane and/or the O
2
–
-forming oxidase. 相似文献
75.
Linda Wittkop Daniel Commenges Isabelle Pellegrin Dominique Breilh Didier Neau Denis Lacoste Jean-Luc Pellegrin Geneviève Chêne François Dabis Rodolphe Thiébaut 《BMC medical research methodology》2008,8(1):68
Background
Principal component analysis (PCA) and partial least square (PLS) regression may be useful to summarize the HIV genotypic information. Without pre-selection each mutation presented in at least one patient is considered with a different weight. We compared these two strategies with the construction of a usual genotypic score. 相似文献76.
Lack of protection in mice and necrotizing bronchointerstitial pneumonia with bronchiolitis in guinea pigs immunized with vaccines directed against the hsp60 molecule of Mycobacterium tuberculosis 下载免费PDF全文
Turner OC Roberts AD Frank AA Phalen SW McMurray DM Content J Denis O D'Souza S Tanghe A Huygen K Orme IM 《Infection and immunity》2000,68(6):3674-3679
In this study, the hsp60 and hsp70 heat shock protein antigens of Mycobacterium tuberculosis were tested as potential vaccine candidates, using purified recombinant protein antigens or antigens encoded in the form of a DNA plasmid vaccine. Guinea pigs vaccinated with a mixture of the two proteins showed no evidence of resistance to low-dose aerosol challenge infection and quickly developed severe lung damage characterized by necrotizing bronchointerstitial pneumonia and bronchiolitis. As a result, we turned instead to a DNA vaccination approach using a plasmid encoding the hsp60 antigen of M. tuberculosis. Although immunogenic in mice, vaccination with plasmid DNA encoding hsp60 was not protective in that model or in the guinea pig model and again gave rise to similar severe lung damage. This study seriously questions the safety of vaccines against tuberculosis that target highly conserved heat shock proteins. 相似文献
77.
Morvan FO Baroukh B Ledoux D Caruelle JP Barritault D Godeau G Saffar JL 《The American journal of pathology》2004,164(2):739-746
Oral mucositis is a common, treatment-limiting, and costly side effect of cancer treatments whose biological underpinnings remain poorly understood. In this study, mucositis induced in hamsters by 5-fluorouracil (5-FU) was observed after cheek-pouch scarifications, with and without administration of RGTA (RG1503), a polymer engineered to mimic the protective effects of heparan sulfate. RG1503 had no effects on 5-FU-induced decreases in body weight, blood cell counts, or cheek-pouch and jejunum epithelium proliferation rates, suggesting absence of interference with the cytotoxic effects of 5-FU. Extensive mucositis occurred in all of the untreated animals, and consisted of severe damage to cheek pouch tissues (epithelium, underlying connective tissue, and muscle bundles). Only half of the RG1503-treated animals had mucositis, over a mean area 70% smaller than in the untreated animals. Basement membranes were almost completely destroyed in the untreated group but was preserved in the RG1503 group. RG1503 blunted or abolished the following 5-FU-induced effects: increases in matrix metalloproteinase (MMP)-2, MMP-9, and plasmin, and decreases in tissue inhibitor of metalloproteinase (TIMP)-1 and TIMP-2. These data indicate that mucositis lesions are related to massive release of proteolytic enzymes and are improved by RG1503 treatment, this effect being ascribable in part to restoration of the MMP-TIMP balance. RG1503 given with cancer treatment might protect patients from mucositis. 相似文献
78.
79.
Variable Regions 1 and 2 (VR1 and VR2) in JSRV gag Are Not Responsible for the Endogenous JSRV Particle Release Defect 总被引:4,自引:0,他引:4
Jaagsiekte sheep retrovirus (JSRV) is a betaretrovirus causing ovine pulmonary adenocarcinoma, a transmissible lung tumor of sheep. A very closely related endogenous retrovirus (enJSRV) occurs as 15 to 20 copies in the genome of all sheep, and is not known to be linked to pathogenesis. We previously localized a particle release defect of the full-length endogenous-derived expression construct pCMV2enJS56A1 to the amino-terminal region of gag that incorporates the two variable regions VR1 and VR2, which harbor the main sequence differences between endogenous and exogenous JSRV in this part of gag. Here, we tested the hypothesis that either or both of these variable regions are responsible for the observed particle release defect in enJS56A1. We found that the PPPPPPPS motif of the exogenous VR1 is neither necessary nor sufficient for particle release. Furthermore, the precise substitution of VR1 and VR2 in the exogenous JSRV expression plasmid pCMV2JS 21, using their enJS56A1-derived counterparts, did not abrogate the ability of the resulting constructs to release particles. The particle release defect of enJS56A1 is therefore not determined exclusively by either VR1 or VR2. These results point to a small number of amino acids lying outside of VR1 and VR2 that may be responsible for the particle defect of enJS56A1 Gag. 相似文献
80.
Adrenocortical adenoma and carcinoma: histopathological and molecular comparative analysis. 总被引:8,自引:0,他引:8
Alexander Stojadinovic Murray F Brennan Axel Hoos Atilla Omeroglu Denis H Y Leung Maria E Dudas Aviram Nissan Carlos Cordon-Cardo Ronald A Ghossein 《Modern pathology》2003,16(8):742-751
We compared histomorphological features and molecular expression profiles of adrenocortical adenomas (ACAd) and carcinomas (ACCa). A critical histopathological review (mean, 11 slides per patient) was conducted of 37 ACAd and 67 ACCa. Paraffin-embedded tissue cores of ACAd (n = 33) and ACCa (n = 38) were arrayed in triplicate on tissue microarrays. Expression profiles of p53, mdm-2, p21, Bcl-2, cyclin D1, p27, and Ki-67 were investigated by immunohistochemistry and correlated with histopathology and patient outcome using standard statistical methodology. Median follow-up period was 5 years. Tumor necrosis, atypical mitoses, and >1 mitosis per 50 high-power fields were factors that were highly specific for ACCa (P <.001). Number (0 to 4) of unfavorable markers [Ki-67 (+), p21 (+), p27 (+), mdm-2(-)] expressed was significantly associated with mitotic activity and morphologic index (i.e., number of adverse morphologic features) and highly predictive of malignancy (P <.001). Ki-67 overexpression occurred in 0 ACAd and 36% ACCa (P <.001) and was significantly associated with mitotic rate and unfavorable morphologic index (P <.001). Tumor necrosis, atypical mitoses, >5 mitoses per 50 high-power fields, sinusoidal invasion, histologic index of >5, and presence of more than two unfavorable molecular markers were associated significantly with metastasis in ACCa. Well-established histopathologic criteria and Ki-67 can specifically distinguish ACCAd from ACCa. Tumor cell proliferation (Ki-67) correlates with mitotic activity and morphologic index. Tumor morphology is a better predictor of metastatic risk in ACCa than current immunohistochemistry-detected cell cycle regulatory and proliferation-associated proteins. 相似文献