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61.
H?Bukulmez AL?Matthews CM?Sullivan C?Chen MJ?Kraay RC?Elston RW?Moskowitz VM?Goldberg ML?WarmanEmail author 《Arthritis research & therapy》2005,8(1):R25
In order to determine whether there is a genetic component to hip or knee joint failure due to idiopathic osteoarthritis (OA),
we invited patients (probands) undergoing hip or knee arthroplasty for management of idiopathic OA to provide detailed family
histories regarding the prevalence of idiopathic OA requiring joint replacement in their siblings. We also invited their spouses
to provide detailed family histories about their siblings to serve as a control group. In the probands, we confirmed the diagnosis
of idiopathic OA using American College of Rheumatology criteria. The cohorts included the siblings of 635 probands undergoing
total hip replacement, the siblings of 486 probands undergoing total knee replacement, and the siblings of 787 spouses. We
compared the prevalence of arthroplasty for idiopathic OA among the siblings of the probands with that among the siblings
of the spouses, and we used logistic regression to identify independent risk factors for hip and knee arthroplasty in the
siblings. Familial aggregation for hip arthroplasty, but not for knee arthroplasty, was observed after controlling for age
and sex, suggesting a genetic contribution to end-stage hip OA but not to end-stage knee OA. We conclude that attempts to
identify genes that predispose to idiopathic OA resulting in joint failure are more likely to be successful in patients with
hip OA than in those with knee OA. 相似文献
62.
One of the cellular defenses against virus infection is the silencing of viral gene expression. There is evidence that at
least two gene-silencing mechanisms are used against the human immuno-deficiency virus (HIV). Paradoxically, this cellular
defense mechanism contributes to viral latency and persistence, and we review here the relationship of viral latency to gene-silencing
mechanisms. 相似文献
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64.
Nitrogen fixation (acetylene reduction) on a coral reef 总被引:2,自引:1,他引:2
Nitrogen fixation rates associated with various substrates on a fringing reef at Eilat, Red Sea, were estimated by in situ acetylene reduction. High rates of acctylene reduction were associated with bare substrates, such as sand and dead coral skeletons. Low rates of acetylene reduction were associated with substrates covered by macroalgae or living coral tissue. Estimates of nitrogen fixation in various reef zones, based on these measurements, indicate that the sand-covered lagoon is responsible for more than 70% of the fixation in the reef. Consequently, the lagoon may serve as an important source of nitrogen for the coral reef community. 相似文献
65.
Belinky F Szitenberg A Goldfarb I Feldstein T Wörheide G Ilan M Huchon D 《Molecular phylogenetics and evolution》2012,63(3):702-713
Phylogenetic relationships within sponge classes are highly debated. The low phylogenetic signal observed with some current molecular data can be attributed to the use of few markers, usually slowly-evolving, such as the nuclear rDNA genes and the mitochondrial COI gene. In this study, we conducted a bioinformatics search for a new molecular marker. We sought a marker that (1) is likely to have no paralogs; (2) evolves under a fast evolutionary rate; (3) is part of a continuous exonic region; and (4) is flanked by conserved regions. Our search suggested the nuclear ALG11 as a potential suitable marker. We next demonstrated that this marker can indeed be used for solving phylogenetic relationships within sponges. Specifically, we successfully amplified the ALG11 gene from DNA samples of representatives from all four sponge classes as well as from several cnidarian classes. We also amplified the 18S rDNA and the COI gene for these species. Finally, we analyzed the phylogenetic performance of ALG11 to solve sponge relationships compared to and in combination with the nuclear 18S rDNA and the COI mtDNA genes. Interestingly, the ALG11 marker seems to be superior to the widely-used COI marker. Our work thus indicates that the ALG11 marker is a relevant marker which can complement and corroborate the phylogenetic inferences observed with nuclear ribosomal genes. This marker is also expected to contribute to resolving evolutionary relationships of other apparently slow-evolving animal phyla, such as cnidarians. 相似文献
66.
Are cryptic species of the Lesser Egyptian Jerboa,Jaculus jaculus (Rodentia,Dipodidae), really cryptic? Re‐evaluation of their taxonomic status with new data from Israel and Sinai 下载免费PDF全文
Georgy Shenbrot Tamar Feldstein Shai Meiri 《Journal of Zoological Systematics and Evolutionary Research》2016,54(2):148-159
Two clades of the lesser Egyptian jerboa Jaculus jaculus sensu lato were recently described in North Africa and considered as cryptic species. Members of both clades are also found in Israel, where they can be easily identified according to fur and tail colouration and morphology of the male external genitalia, but cannot be separated confidently using skull characters. Examination of type specimens demonstrated that the correct names for the two species are Jaculus jaculus (Linnaeus 1758) and Jaculus hirtipes (Lichtenstein, 1823). Comparisons of geographic and habitat differences of the two species revealed a high niche divergence between them, slightly higher in the sympatric North African populations than in the parapatric populations of Israel and Sinai. A low niche divergence was detected between North African and Middle Eastern populations of J. jaculus, and a low niche convergence between North African and Middle Eastern populations of J. hirtipes. The levels of niche differentiation coincide with those of genetic differences. 相似文献
67.
Rowe-Taitt CA Golden JP Feldstein MJ Cras JJ Hoffman KE Ligler FS 《Biosensors & bioelectronics》2000,14(10-11):785-794
A fluorescence-based biosensor has been developed for simultaneous analysis of multiple samples for multiple biohazardous agents. A patterned array of antibodies immobilized on the surface of a planar waveguide is used to capture antigen present in samples; bound analyte is then quantified by means of fluorescent tracer antibodies. Upon excitation of the fluorophore by a small diode laser, a CCD camera detects the pattern of fluorescent antibody:antigen complexes on the waveguide surface. Image analysis software correlates the position of fluorescent signals with the identity of the analyte. This array biosensor has been used to detect toxins, toxoids, and killed or non-pathogenic (vaccine) strains of pathogenic bacteria. Limits of detection in the mid-ng/ml range (toxins and toxoids) and in the 10(3)-10(6) cfu/ml range (bacterial analytes) were achieved with a facile 14-min off-line assay. In addition, a fluidics and imaging system has been developed which allows automated detection of staphylococcal enterotoxin B (SEB) in the low ng/ml range. 相似文献
68.
Carbonic anhydrase purified from the saliva of the rat had kinetic properties identical with those of carbonic anhydrase II from rat red cells, but its molecular properties were distinctly different from the type II isozyme. Kinetic parameters were measured under steady state conditions by stopped-flow spectrophotometry and under equilibrium conditions by an 18O exchange method. The turnover number kcat for hydration of CO2 was 6.5 X 10(4) s-1 and the Michaelis constant was 4.2 mM at pH 7.5 and 25 degrees C, values which are equal to the steady state constants for red cell carbonic anhydrase II from the rat. Inhibition of the salivary isozyme by sulfanilamide (Ki = 3.7 microM) was nearly as efficient as inhibition of the erythrocyte isozyme II (Ki = 1.1 microM). The molecular weight for the salivary isozyme was 46,000 and the isoelectric point was 5.5. Salivary carbonic anhydrase had high mannose oligosaccharide components as measured by concanavalin A binding. The amino acid composition for the salivary isozyme was not similar to rat type II, but it was similar to that reported for membrane-bound carbonic anhydrase from bovine lung (Whitney, P.L., and Briggle, T.V. (1982) J. Biol. Chem. 257, 12056-12059). These observations suggest to us that salivary carbonic anhydrase is a secretory product. 相似文献
69.
70.
Davide Povero Akiko Eguchi Hongying Li Casey D. Johnson Bettina G. Papouchado Alexander Wree Karen Messer Ariel E. Feldstein 《PloS one》2014,9(12)