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81.
Human leukocyte antigen matching and fetal loss: results of a 10 year prospective study 总被引:6,自引:0,他引:6
Ober C; Hyslop T; Elias S; Weitkamp LR; Hauck WW 《Human reproduction (Oxford, England)》1998,13(1):33-38
The role that maternal and fetal human leukocyte antigen (HLA) genes play
in pregnancy is unknown, but it has been suggested that fetuses whose HLA
alleles do not differ from maternal alleles (i.e. histocompatible fetuses)
are more likely to be aborted than fetuses with HLA alleles that differ
from maternal alleles (i.e. histoincompatible fetuses). To elucidate the
role of HLA compatibility in pregnancy, we tested the hypothesis that
couples who match for HLA alleles or haplotypes would have reduced
fertility because only these couples could produce histocompatible fetuses.
We conducted a 10 year prospective study of HLA matching and pregnancy
outcome in 111 Hutterite couples, providing information on 251 pregnancies.
A logistic regression analysis was performed to determine the effects of
HLA matching at HLA regions and loci on pregnancy outcome (fetal loss
versus delivery). Significantly increased fetal loss rates were observed
among couples matching for the entire 16-locus haplotype (P = 0.002). Among
the individual loci, loss rates were increased among couples matching for
HLA-B (P = 0.019), HLA-C (P = 0.033) and the complement component, C4 (P =
0.043). We interpret these results as evidence that matching for the entire
16-locus haplotype and/or alleles at an HLA-B-linked locus confers
significant risk for fetal loss.
相似文献
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Diacylated (e.g. MALP-2) and triacylated (Pam(3)Cys derivatives) lipopeptides, deriving from the N-terminal moiety of respectively mycoplasmal and E. coli lipoproteins, are powerful adjuvants recognized by Toll-like receptors (TLR) which have been used successfully to trigger cell activation and immune responses. To design liposome-based vaccination constructs in which Th and CTL epitopes are conjugated to synthetic lipopeptide analogues anchored into the bilayers of the vesicles, the peptide moieties of the lipopeptides were functionalized with thiol-reactive groups, such as maleimide (Mal) or bromoacetyl, incorporated into liposomes and reacted with thiol carrying peptide epitopes. Because dendritic cells (DCs) play a key role as antigen-presenting cells in immune responses, in the present study we have evaluated the impact of the functionalization of lipopeptide analogues Pam(2)CAG, Pam(3)CAG and Ol(3)GAG on the phenotypic maturation of human monocyte-derived DCs. The intrinsic cellular activities of the lipopeptide analogues incorporated into liposomes were monitored, in vitro, by measuring the up-regulation of the cell-surface markers CD80, CD83, CD86 and HLA-DR. We found that in some cases their functionalization with thiol-reactive groups led to a loss of activity. The stimulatory potency can be ranked in the following order: Pam(3)CAG>/=Pam(2)CAG-Mal-Th approximately Pam(2)CAG-Mal>Pam(3)CAG-Mal-Th (where Th is a HS-peptide) and no appreciable activity was detected for Pam(3)CAG-Mal, Ol(3)CAG-Mal and Ol(3)CAG-Mal-Th. Our findings indicate that subtle modifications in the peptide moiety of lipopeptides have a great impact on the immunomodulatory properties of these molecules. For the engineering of liposome/lipopeptide-based vaccines, the maleimide derivative of Pam(2)CAG appears to be the best candidate. 相似文献
85.
Gastrointestinal stromal tumors (GISTs)--the Lebanese experience 总被引:1,自引:0,他引:1
Salamoun W El Hajj G Aftimos G Moukharbel N Khairallah S Bejjani N Abou Sleiman CH Abou Atmeh J Azar H Elias E Abi Gerges D 《Molecular immunology》2003,39(17-18):1129-1132
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87.
Serum immunoreactive trypsin concentration after a Lundh meal. Its value in the diagnosis of pancreatic disease.
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G Lake-Bakaar S McKavanagh M Redshaw T Wood J A Summerfield E Elias 《Journal of clinical pathology》1979,32(10):1003-1008
The changes in serum trypsin concentration have been measured in 47 subjects for up to 2 hours after a Lundh meal. In 18 healthy controls, mean fasting trypsin concentration was 285 +/- 125 ng/ml (mean +/- 2 SD). The maximum increase after the Lundh meal (the trypsin response ratio) was 6.7 +/- 7.5%. Six patients with chronic renal failure had elevated fasting serum trypsin concentrations (range 460-1100 ng/ml) but trypsin response ratios fell within the control range. Of five patients with relapsing pancreatitis, two had raised and three normal or low fasting trypsins. After stimulation two had elevated trypsin response ratios; one of the two had evidence of main duct obstruction. Eleven out of 12 patients with chronic pancreatitis (with or without insufficiency) had low fasting trypsin concentrations (range 0-120 ng/ml) Seven of the 12 also had raised trypsin response ratios. In six patients with cancer of the pancreas, fasting trypsin was low in three, normal in two, and raised in one. Both patients with a normal fasting level had a raised trypsin response ratio. The combination of a single estimation of fasting serum trypsin concentration followed by serial measurements after a Lundh meal provides a useful screening test for chronic pancreatic disease. 相似文献
88.
Shields CM Taylor R Nazarenus T Cheatle J Hou A Tapprich A Haifley A Atkin AL 《Current genetics》2003,44(4):184-194
Saccharomyces cerevisiae ATS1 (-tubulin suppressor 1) was originally identified as a high-copy suppressor of class two -tubulin mutations and was proposed to have a regulatory role in coordinating the microtubule state with the cell cycle. Here, we show that Ats1p interacts with Nap1p, a cytoplasmic protein that regulates the activity of the Cdc28p/Clb2p complex. Loss of Nap1p results in a delayed switch from polar to isotropic bud growth. The delayed switch results in elongated buds. Nap1p and Ats1p interact in two-hybrid and co-immunoprecipitation assays. Both nap1 and ats1 cells have a Clb2p-dependent elongated bud morphology. Deletion of ATS1 partially suppresses the elongated bud morphology and benomyl resistance of nap1 mutants. Our results suggest Ats1p might regulate coordination of the microtubule state with the cell cycle through an interaction with Nap1p.Communicated by S. Hohmann 相似文献
89.
Gontijo AM Marcondes JP Elias FN de Oliveira ML de Lima RO Salvadori DM de Camargo JL 《Environmental and molecular mutagenesis》2002,40(3):190-199
In order to determine if patients with a history of previous urothelial cell carcinoma (UCC) but with current normal urinary cytology have DNA damage in urothelial cells, the single-cell gel electrophoresis (comet) assay was conducted with cells obtained by urinary bladder washings from 44 patients (28 with a history of previous UCC). Increased DNA damage was observed in cytologically "normal" urothelial cells of patients with a history of UCC when compared with referents with no similar history and after correcting the data for smoking status and age (P < 0.018). Increased DNA damage also correlated with the highest tumor grade, irrespective of time or course of the disease after clinical intervention (Kendall tau correlation, 0.37, P = 0.016). Moreover, aneuploidy, as assessed by DNA content ratio (DCR; 75th/25th percentile of total DNA fluorescence of 50 comets/patient) was unaltered by smoking status, but increased with UCC grade: 1.39 +/- 0.12 (median +/- 95% confidence interval; referents); 1.43 +/- 0.11 (Grade I UCC; P = 0.264, against referents); 1.49 +/- 0.16 (Grade II UCC; P = 0.057); 1.57 +/- 0.16 (Grade III UCC; P = 0.003). Micronucleated urothelial cells (MNC) were also scored on Giemsa-stained routine cytological smears and were found not to correlate with DNA damage or DCR. MNC frequencies were higher for patients with a history of UCC and/or smoking than referents with neither history, but there was no statistical difference between groups. Taken together, these results suggest that the normal-appearing urothelium of patients resected for UCC still harbor genetically unstable cells. 相似文献
90.
Evaluation of a microsphere-based flow cytometric assay for diagnosis of celiac disease 总被引:2,自引:0,他引:2
Yiannaki EE Zintzaras E Analatos A Theodoridou C Dalekos GN Germenis AE 《Journal of immunoassay & immunochemistry》2004,25(4):345-357
The multiplexed particle-based flow cytometric technology proposes a new approach for the diagnosis of autoimmune diseases combining the advantages of conventional methods with the ability to quantitatively determine multiple autoantibodies in the same sample, simultaneously and rapidly. Recently, a commercial kit (FIDIS Celiac, Biomedical Diagnostics, Mane la Vallé, France) was introduced for the simultaneous detection of IgA anti-tissue transglutaminase (anti-tTG), IgG, and IgA anti-gliadin antibodies (AGA). This study was undertaken to evaluate and compare the FIDIS Celiac kit with standardized commercial ELISAs (QUANTA Lite, INOVA Diagnostics Inc., San Diego, CA). A disease group consisted of 21 samples from untreated patients with biopsy confirmed celiac disease (CD), and two control groups of historical sera (207 from regular blood donors and 181 from chronically infected hepatitis patients) were studied. All control sera were negative for IgA anti-endomysial antibodies (EmA) and had an IgA concentration above the lower normal limit. Concerning the reproducibility, intra- and inter-assay coefficients of variation (CVs) ranging between 2% and 12%, and between 3% and 21%, respectively, were observed. Regarding the diagnostic quality, each assay was compared to the disease diagnosis using the McNemar test and the kappa (K) parameter, while ROC analysis was applied. Generally, the performance of FIDIS assay was proved almost equally adequate to that of ELISA in the detection of IgA anti-tTG antibodies, IgA and IgG AGA. However, the performance of FIDIS assay was found surmounting that of ELISA among hepatitis patients, possibly due to the avoidance of debris and unbound cross contaminants and, hence, the "noise" of such materials in samples under analysis. Taking our results together with the simplicity and the high throughput of FIDIS assay, its overall performance in the diagnosis of CD seems better than that of ELISA. 相似文献