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Ahmed Belmouden Marie F. Adam Stéphane Dupont de Dinechin Antoine P. Brézin Philippe Rigault Ilya Chumakov Jean-François Bach Henri-Jean Garchon 《Genomics》1997,39(3):348
Primary open-angle glaucoma (POAG) is a leading cause of irreversible blindness in industrialized countries. A locus for juvenile-onset POAG,GLC1A,has been mapped to 1q21–q31 in a 9-cM interval. With recombinant haplotypes, we have now reduced theGLC1Ainterval to a maximum of 3 cM, between theD1S452/NGA1/D1S210andNGA5loci. These loci are 2.8 Mb apart on a 4.7-Mb contig that we have completed between theD1S2851andD1S218loci and that includes 96 YAC clones and 48 STSs. The newGLC1Ainterval itself is now covered by 25 YACs, 30 STSs, and 16 restriction enzyme site landmarks. The lack of aNotI site suggests that the region has few CpG islands and a low gene content. This is compatible with its predominant cytogenetic location on the 1q24 G-band. Finally, we have excluded important candidate genes, including genes coding for three ATPases (ATP1B1, ATP2B4, ATP1A2), an ion channel (VDAC4), antithrombine III (AT3), and prostaglandin synthase (PTGS2). Our results provide a basis to identify theGLC1Agene. 相似文献
993.
To study the role of Moraxella (subgenus Branhamella) catarrhalis (B. catarrhalis) adherence to airway cells in lower respiratory tract infections, the in vitro attachments of B. catarrhalis to upper airway (oropharyngeal) and lower airway (bronchial) epithelial cells were compared. The adherence of 4 strains (1 nonfimbriated and 3 fimbriated) of B. catarrhalis to respiratory tract epithelial cells collected from 11 patients with chronic pulmonary disease (CPD) and 11 healthy individuals was evaluated. Both the fimbriated and nonfimbriated strains showed increased attachment to oropharyngeal cells in the CPD patients (mean ± SEM; 25.0 ± 3.2/cell; P < 0.01) when compared to the control subjects (12.1 ± 1.1/cell). On the average, the attachment to bronchial cells was 6.1 to 13.6 times greater per surface area (bacteria/μ2) than the attachment to oropharyngeal cells. The fimbriated strains tended to adhere in higher numbers to bronchial cells (19.0 ± 1.8/cell) than the nonfimbriated strain (8.7 ± 1.2/cell), although there was no difference between the CPD and control groups. In conclusion, the attachment of B. catarrhalis to oropharyngeal cells may be an enhancing factor for colonization in the upper respiratory tract in patients with CPD, and elevated adherence of the bacteria to bronchial cells may suggest pathogenic importance when mucociliary function is impaired. 相似文献
994.
We have measured the change of lung mechanical parameters on isolated rabbit lungs exposed to chlorine gas (Cl{in2}). Experimental
results show parallel increase in elastance and resistance of impaired lungs. We tried to determine whether this may be explained
by a reduction of the ventilated areas in the lung, consecutive to closure of some airways. We have then tried to simulate
these experimental results by studying the effects of various airways occlusions imposed on two concurrent models (symmetrical
and dissymmetrical) of the tracheo-bronchial tree. For each model, we successively evaluated the resistance of the normal
lung, simulated a partial peripheral airways occlusion and estimated the induced changes in total resistance. Analytical expressions
of the "occluded lung" elastance and resistance have been found for the symmetrical model but not for the dissymmetrical model
(a graphical approach is proposed). With the symmetrical model, simulated results are comparable to experimental ones when
the occlusion level is proximal. Whatever the dissymmetry level (δ) of the fractal tree model, we could not simulate the expected
increase in resistance with the observed increase in elastance. We conclude that either the occlusion is non homogeneous or
the lung impairment is not only a reduction in ventilated areas.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
995.
The investigation of Chromolaena glaberrima afforded, besides the known heliangolide chromolaenide, a new 4-dehydrochromolaenide. The structure of the new compound was elucidated by spectroscopic methods. 相似文献
996.
Brian D. Smith Gill Braulik † Samantha Strindberg ‡ Benazir Ahmed § Rubaiyat Mansur ¶ 《Marine Mammal Science》2006,22(3):527-547
Independent observer teams made concurrent counts of Irrawaddy dolphins Orcaella brevirostris and Ganges River dolphins Platanista gangetica gangetica in mangrove channels of the Sundarbans Delta in Bangladesh. These counts were corrected for missed groups using mark-recapture models. For Irrawaddy dolphins, a stratified Lincoln-Petersen model, which incorporated group size and sighting conditions as covariates, and a Huggins conditional likelihood model, which averaged models that individually incorporated group size, sighting conditions, and channel width as covariates, generated abundance estimates of 397 individuals (CV = 10.2%) and 451 individuals (CV = 9.6%), respectively. For Ganges River dolphins, a stratified Lincoln-Petersen model, which incorporated group size as a covariate, and a Huggins conditional likelihood model, which averaged the same models described above, generated abundance estimates of 196 individuals (CV = 12.7%) and 225 individuals (CV = 12.6%), respectively. Although the estimates for both models were relatively close, the analytical advantages of the Huggins models probably outweigh those of the Lincoln-Petersen models. However, the latter should be considered appropriate when simplicity is a priority. This study found that waterways of the Sundarbans support significant numbers of Irrawaddy and Ganges River dolphins, especially compared to other areas where the species have been surveyed. 相似文献
997.
Nazish Ahmed Rita Dreier Achim G?pferich Joachim Grifka Susanne Gr?ssel 《Cellular physiology and biochemistry》2007,20(5):665-678
BACKGROUND: Chondral defects show lack of proper regeneration whereas osteochondral lesions display limited regeneration capacity. Latter is probably due to immigration of chondroprogenitor cells from the subchondral bone. Known chondroprogenitor cells for cartilage tissues are multi-potent adult marrow stromal or mesenchymal stem cells (MSCs). In vitro chondrogenic differentiation of these precursor cells usually require cues from growth and signalling factors provided in vivo by surrounding tissues and cells. We hypothesise that signalling factors secreted by differentiated cartilage tissue can initiate and maintain chondrogenic differentiation status of MSCs. METHODS: To study such paracrine communication between allogenic rat articular cartilage and rat MSCs embedded in alginate beads a novel coculture system without addition of external growth factors has been established. RESULTS: Impact of cartilage on differentiating MSCs was observed at two different time points. Firstly, sustained expression of Sox9 was observed at an early stage which indicated induction of chondrogenic differentiation. Secondly, late stage repression of collagen X indicated pre-hypertrophic arrest of differentiation. In the culture supernatant we have identified vascular endothelial growth factor alpha (VEGF-164 alpha), matrix metalloproteinase (MMP) -13 and tissue inhibitors of MMPs (TIMP-1 and TIMP-2) which could be traced back either to the cartilage explant or to the MSCs under the influence of cartilage. CONCLUSION: The identified factors might be involved in regulation of collagen X gene and protein expression and therefore, may have an impact on the control and regulation of MSCs differentiation. 相似文献
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