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21.
The KIR2DL4 gene including a portion of exon 1 through exon 9 was sequenced from two families and eight cell lines from the International Histocompatibility Workshop (IHWS). Two known alleles and eight variants were detected. Overall, there were five synonymous and three non-synonymous changes when the variants were compared to the coding sequences of the most closely related known alleles plus a common frameshift change in five of the variant alleles. Alignment of the new variants with all known alleles showed that the regions encoding the extracellular region and the cytoplasmic tail were the most polymorphic. Two non-synonymous changes, P146H and L161V, occurred in an extracellular immunoglobulin-like domain. Five of the eight variants had a single adenine deletion in the exon encoding the transmembrane region, potentially resulting in a truncated protein lacking the cytoplasmic tail. The distribution of the deletion variant among many KIR2DL4 alleles may explain the high frequency of this variation in the population. Four of the eight consanguineous IHWS cell lines were found to be heterozygous for KIR2DL4 carrying two alleles that differed from one another by a few nucleotide substitutions. Analysis of intron sequences in the families revealed the nature and distribution of interspersed repeat elements which comprise 46% of the KIR2DL4 nucleotide sequence and consist of 12 elements including six SINEs (13.73% of the total length), one LINE (12.41%), and five LTR elements (19.51%). The results revealed the presence of extensive diversity in the KIR2DL4 gene. This is the first extensive report providing both exon and intron data in related individuals. 相似文献
22.
The prevalence of antibody against Toxoplasma gondi in a population of 715 pregnant women has been evaluated by two methods: indirect haemagglutination antibody (IHA) and indirect fluorescent antibody (IFA) test and all positive sera were checked by the dye test. Five hundred of the study population were questioned on diet and on animal contact to elucidate a possible relation to the prevalence of antibody. Results are expressed in international units (IU) of antibody against T gondi. Of the 715 sera, 171 were positive by IHA and 173 by IFA. One hundred and sixty-seven sera were positive by both tests, ninety-eight (58%) correlating exactly, as to the concentration of antibody. The ten sera which were not positive by both tests all had detectable antibody at the minimum concentration only (12 IU). The dye test confirmed all sera positive by both tests with the exception of three. It also confirmed one of four sera positive by IHA antibody alone and two of six positive by IFA alone. All sera that proved dye test-negative had low antibody concentrations (12 IU) by IHA or IFA. The IHA test, which is commercially available in kit form, would be suitable for use as a screening test during pregnancy. The estimated annual rate of antibody acquisition over the age range 16-40 years is 1.2% per annum with the highest rate in the 36-40 age group (2.5% per annum) and the lowest in the 26-30 age group (0.4% per annum). The clinical history was not significantly different between those with and those without antibody against T gondi but significantly more women in the 36-40 age group had a history of animal contact than those in the 26-30 age group. No conclusive evidence of recent or current infection was found. 相似文献
23.
New alleles in the B44 family including B*44022, B*44032, B*4411, B*4420, B*4421, B*4424, and B*8301
Steiner NK Gans CP Kosman C Bradshaw D Koester R Menchaca EM Mitton W Ng J Hartzman RJ Hurley CK 《Tissue antigens》2001,57(4):376-379
Seven new HLA-B locus alleles have been described. B*44022 and B*44032 are silent substitutions altering known alleles. B*4411 carries a unique Bw4-like epitope. B*4420, B*4421, and B*4424 carry new combinations of motifs previously observed in other alleles. B*8301 appears to be the result of the replacement of exon 2 from B*4402 with exon 2 from B*5603. 相似文献
24.
Axial and appendicular bone mineral density in patients with long-term deficiency or excess of calcitonin 总被引:2,自引:0,他引:2
Whether calcitonin deficiency causes and calcitonin excess prevents bone loss is controversial. We therefore measured plasma calcitonin levels and bone mineral density at the radius (by single photon absorptiometry) and lumbar spine (dual photon absorptiometry) in patients with an excess or deficiency of calcitonin. We studied 21 patients who had undergone subtotal thyroidectomy 6.8 to 29 years previously and had no calcitonin secretory reserve, and 11 patients who had received a diagnosis of medullary thyroid carcinoma 6.8 to 23 years previously and had chronic hypercalcitoninemia. Bone-density values, expressed as Z-scores (i.e., as the number of standard deviations above or below the normal means adjusted for age and sex), were indistinguishable from normal in the patients who had undergone thyroidectomy (means +/- SE: radius, 0.36 +/- 0.15; spine, 0.27 +/- 0.17). In the patients with medullary thyroid cancer, radial bone-density values were normal (-0.26 +/- 0.39), but spinal density was significantly reduced (-0.75 +/- 0.17, P less than 0.01). There were no significant correlations between the duration of calcitonin excess or deficiency and the bone density at either site. Bone mineral density was not affected by whether or not thyroxine replacement therapy was given. We conclude that skeletal mass is not affected by endogenous plasma calcitonin in adults. 相似文献
25.
26.
Hurley CK Steiner N Gans CP Kosman C Mitton W Koester R Jones P Edson S Rizzuto G Hartzman RJ Ng J Rodriguez-Marino SG 《Tissue antigens》2001,57(5):474-477
Twelve new B*15 alleles are described. All of the known B*15 alleles are divided into subgroups based on serologic assignments and/or nucleotide sequence polymorphisms. These groups might be used as a reference for DNA-based testing at an intermediate (i.e. "serologic") level of resolution. 相似文献
27.
Schreuder GM Hurley CK Marsh SG Lau M Maiers M Kollman C Noreen HJ 《Human immunology》2001,62(8):826-849
This report presents the serologic equivalents of 123 HLA-A, 272 HLA-B, and 155 HLA-DRB1 alleles. The equivalents cover over 64 percent of the presently identified HLA-A, -B, and -DRB1 alleles. The dictionary is an update of the one published in 1999 (Schreuder GMTh, Hurley CK, Marsh SGE, Lau M, Maiers M, Kollman C, Noreen H. The HLA dictionary 1999: a summary of HLA-A, -B, -C, -DRB1/3/4/5, -DQB1 alleles and their association with serologically defined HLA-A, -B, -C, -DR and -DQ antigens. Tissue Antigens 54:407, 1999) and also includes equivalents for HLA-C, DRB3, DRB4, DRB5, and DQB1 alleles. The data summarize information obtained by the WHO Nomenclature Committee for Factors of the HLA System, the International Cell Exchange (UCLA), the National Marrow Donor Program (NMDP), and individual laboratories. In addition, a listing is provided of alleles which are expressed as antigens with serologic reaction patterns that differ from the well-established HLA specificities. The equivalents provided will be useful in guiding searches for unrelated hematopoietic stem cell donors in which patients and/or potential donors are typed by either serology or DNA-based methods. These equivalents will also serve typing and matching procedures for organ transplant programs where HLA typings from donors and from recipients on waiting lists represent mixtures of serologic and molecular typings. The tables with HLA equivalents and a questionnaire for submission of serologic reaction patterns for poorly identified allelic products will also be available on the WMDA web page: www.worldmarrow.org. 相似文献
28.
Rabon-Stith KM Hagberg JM Phares DA Kostek MC Delmonico MJ Roth SM Ferrell RE Conway JM Ryan AS Hurley BF 《Experimental physiology》2005,90(4):653-661
To determine the influence of the vitamin D receptor (VDR) gene FokI and BsmI genotype on bone mineral density response to two exercise training modalities, 206 healthy men and women (50-81 years old) were studied before and after approximately 5-6 months of either aerobic exercise training (AT) or strength training (ST). A totla of 123 subjects completed AT (51 men, 72 women) and 83 subjects completed ST (40 men, 43 women). DNA was extracted from blood samples of all subjects and genotyping was performed at the VDR FokI and BsmI locus to determine its association to training response. Total body, greater trochanter and femoral neck bone mineral density (BMD) were measured before and after both training programmes using dual-energy X-ray absorptiometry. VDR BsmI genotype was not significantly related to BMD at baseline or after ST or AT. However, VDR FokI genotype was significantly related to ST- but not AT-induced changes in femoral neck BMD (P < 0.05). The heterozygotes (Ff) in the ST group approached a significantly greater increase in femoral neck BMD (P = 0.058) compared to f homozygotes. There were no significant genotype relationships in the AT group. These data indicate that VDR FokI genotype may influence femoral neck BMD response to ST, but not AT. 相似文献
29.
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
30.
Abstract: Low and high resolution sequence specific oligonucleotide probe hybridization patterns were used to design an approach to direct sequencing of allele specific amplified cDNA. Several PCR amplifications were used to derive overlapping sequence fragments to define complete first domain sequences for a single allele. This method has been used to characterize three new DRB1 alleles in the DR52 family, DRB1*1115, DRB1* 1117, and DRB1*1319. All three alleles carry polymorphisms previously observed in other DRB alleles and underscore the importance of utilizing a directed sequencing approach for obtaining unambiguous typing results in matching for bone marrow transplantation between unrelated donor and recipient. 相似文献