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61.
J. R. NEEFE JR. H. BALNER A. D. BARNES C. FORD G. N. ROOENTINE JR. W. VAN VREESWIJK F. E. WARD 《Tissue antigens》1975,6(2):77-79
The Second International Nonhuman Primate Histocompatibility Workshop permitted comparison of rhesus monkey alloantisera developd in various laboratories on a single common panel of related and unrelated monkeys. Analysis of the data permits the conclusion that at least nine specificities are recognized by more than one laboratory, including six at the first locus and three at the second locus. 相似文献
62.
Immune reactions associated with silicone-based ventriculo-peritoneal shunt malfunctions in children
VandeVord PJ Gupta N Wilson RB Vinuya RZ Schaefer CJ Canady AI Wooley PH 《Biomaterials》2004,25(17):3853-3860
The implantation of ventriculo-peritoneal (VP) shunting systems is the most commonly performed neurological procedure in children with hydrocephalus. Although the overall complication risk is low, the cumulative risk of shunt failure is high and unfortunately results in a high prevalence of revision surgeries. In this study, we explored the concept that some pediatric patients may develop an immune response to either the proteins attached to the silicone implant surface or to the biomaterial itself, and that this reaction may contribute to VP shunt failure in some individuals. The data displays that the sterile shunt malfunction group had a higher rate of protein deposition and increased levels of autoantibodies to the extracted surface proteins as compared to individuals with functioning shunting systems. The precise nature of the shunt-bound proteins that serve as antigens in this experiment have not yet been determined. The data also indicated that some individuals develop antibodies to polymeric substances that cross-react with partially polymerized acrylamide. The detection of significant amounts of shunt-bound protein, antibody responses to these proteins and to polymeric substances suggest that an immunological response to these proteins may play a role in the mechanism behind sterile shunt malfunctions. 相似文献
63.
Linkage of the MHC to familial multiple sclerosis suggests genetic heterogeneity. The Multiple Sclerosis Genetics Group 总被引:5,自引:0,他引:5
Haines JL; Terwedow HA; Burgess K; Pericak-Vance MA; Rimmler JB; Martin ER; Oksenberg JR; Lincoln R; Zhang DY; Banatao DR; Gatto N; Goodkin DE; Hauser SL 《Human molecular genetics》1998,7(8):1229-1234
Multiple sclerosis (MS) is a demyelinating autoimmune disease of the
central nervous system. While its etiology is not well understood, genetic
factors are clearly involved. Until recently, most genetic studies in MS
have been association studies using the case-control design testing
specific candidate genes and studying only sporadic cases. The only
consistently replicated finding has been an association with the HLA-DR2
allele within the major histocompatibility complex (MHC) on chromosome 6.
Using the genetic linkage design, however, evidence for and against linkage
of the MHC to MS has been found, fostering suggestions that sporadic and
familial MS have different etiologies. Most recently, two of four genomic
screens demonstrated linkage to the MHC, although specific allelic
associations were not tested. Here, a dataset of 98 multiplex families was
studied to test for an association to the HLA-DR2 allele in familial MS and
to determine if genetic linkage to the MHC was due solely to such an
association. Three highly polymorphic markers (HLA-DR, D6S273 and TNFbeta)
in the MHC demonstrated strong genetic linkage (parametric lod scores of
4.60, 2.20 and 1.24, respectively) and a specific association with the
HLA-DR2 allele was confirmed (TDT; P < 0.001). Stratifying the results
by HLA-DR2 status showed that the linkage results were limited to families
segregating HLA-DR2 alleles. These results demonstrate that genetic linkage
to the MHC can be explained by the HLA-DR2 allelic association. They also
indicate that sporadic and familial MS share a common genetic
susceptibility. In addition, preliminary calculations suggest that the MHC
explains between 17 and 62% of the genetic etiology of MS. This
heterogeneity is also supported by the minority of families showing no
linkage or association with loci within the MHC.
相似文献
64.
The Gm-Pi linkage heterogeneity in view of Pi M subtypes 总被引:1,自引:3,他引:1
T. GEDDE-DAHL JR R. R. FRANTS† B. OLAISEN† A. W. ERIKSSON† E. VAN LOGHEM§ L. LAMM¶ 《Annals of human genetics》1981,45(2):143-153
In this study linkage between the loci for Gm (γ-type heavy-chain immunoglobulin markers) and Pi (α1 -antitrypsin/α1 -protease inhibitor) has been shown in families segregating for the Pi M subtypes (Ml, M2, M3 and Msal) as identified by separator isoelectric focusing. The estimate for the Gm-Pi (M-type) recombination is 0-29 (95% limits 0-24-O37) at a peak lod score of 4-31 and with no sex difference. This value is not significantly different from updated recombination frequency estimates for Gm-Pi in Pi MS (0-26) and Pi MZ, SZ and FZ families (0 21). The overall Gm-Pi recombination fraction estimate of 0 26 (95 % limits O23-0-30) at a peak lod score of 20-75 must now be considered as solid. There is a significant heterogeneity within the male Pi MZ families in that the new Finnish families show a higher recombination between Gm and Pi. There is also a possible segregation distortion (Z:M = 23:8). The heterogeneity is discussed in terms of haplotypes, the behaviour of which could be determined by linked genes or chromosomal rearrangements. The possibility that the α1 -antitrypsin level influences recombination frequency has not been ruled out, but cannot explain the heterogeneity within Pi MZ families. 相似文献
65.
Settmacher B Rheinheimer C Hamacher H Ames RS Wise A Jenkinson L Bock D Schaefer M Köhl J Klos A 《European journal of immunology》2003,33(4):920-927
The anaphylatoxic peptide C3a is a pro-inflammatory mediator generated during complement activation, whose specific G protein coupled receptor is expressed on granulocytes, monocytes, mast cells, activated lymphocytes, and in the nervous tissue. We have generated RBL-2H3 cell clones stably expressing mutants of the human C3a-receptor (C3aR) with combined alanine (Ala) substitutions of ten C-terminal serine (Ser) or threonine (Thr) residues, which may represent putative phosphorylation sites to characterize their role in ligand-induced C3aR internalization and signaling. Ser475/479 and Thr480/481 as well as Ser449 seemed not to be involved in ligand-induced receptor internalization. Either directly or by a conformational change they even "inhibit" C3aR internalization. In contrast, mutants with Ala substitutions at Ser465/470 and Thr463/466 were poorly internalized, and Thr463 seemed to be the most important C-terminal Thr or Ser residue directly effecting receptor internalization. However, it is likely that other C3aR regions additionally participate in this negative feed-back mechanism since even mutants with multiple Ala substitutions still internalized to a limited degree. Interestingly, in a mutant with a single exchange of Ser449 to Ala, the signal transduction assessed by a Ca(2+) assay and [(35)S]GTP gamma S-binding on HEK cells transiently co-transfected with G-alpha 16 or G-alpha O, respectively, was severely impaired, indicating that this residue of C3aR is involved in G protein coupling. 相似文献
66.
K. Schaefer H. -U. Koch A. Opitz D. von Herrath H. Knoop 《Journal of molecular medicine (Berlin, Germany)》1970,48(18):1129-1131
Zusammenfassung Es wurden Untersuchungen über den Langzeitmetabolismus von Vitamin D bei Normalpersonen und Patienten mit Niereninsuffizienz durchgeführt. Nach intravenöser Injektion von Vitamin D3-H3 zeigte sich in den untersuchten Serumproben weder für die Halbwertszeit noch für die Verteilung von Vitamin D und seinen verschiedenen Metaboliten ein Unterschied zwischen den beiden Gruppen. Diese Untersuchungsergebnisse machen es sehr unwahrscheinlich, daß eine Vitamin D-Stoffwechselstörung für die Entwicklung der azotämischen Osteopathie verantwortlich ist.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
Summary Investigations have been performed in normal subjects and renal patients on the long term metabolism of vitamin D3. After an intravenous injection of tritiated vitamin D3 there was no difference between both groups: halflife and the distribution of vitamin D and its various metabolites in the serum were almost identical. Our results suggest that a disorder of vitamin D metabolism is not responsible for the development of the azotemic osteodystrophy.
Mit Unterstützung der Deutschen Forschungsgemeinschaft. 相似文献
67.
Giardia lamblia cysts obtained from human symptomatic and asymptomatic donors were excysted in vitro. Excystation averaged 87% for cysts from symptomatic donors and 70% for cysts from asymptomatic donors. 相似文献
68.
The ramification of the portal vein at the porta hepatis was studied by anatomic dissection performed in 32 formalin fixed human livers. In all the specimens there were branches which ran towards the caudate lobe, arising from the portal vein and either from the left or the right portal branches. Tri-and quadrifurcation of the portal vein was observed. In 5 cases (16%) there were branches arising from left portal branch or portal vein and directed anteriorly to the quadrate lobe or to the region of the gall-bladder sulcus. These branches ranged from 1.0 to 6.0 mm in diameter. The portal caudate branches were divided into 3 groups.Group 1: Branches to the papillary process; 1 or 2 branches in 26 cases (82%), 3 or 5 branches in 3 cases (9%) and no branches in 3 cases (9%); 相似文献
69.
70.