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1.
Abstract: We compared the mixed lymphocyte culture reaction (MLR-I) among unrelated individuals who are carriers of the extended haplotype [HLA-B8, SC01, DR3, DRB1*0301, DQB1*0201] on one chromosome and the generic specificity HLA-DR4 on the second chromosome. Genomic DNA samples from the same individuals were also analyzed for HLA-DRB1, DQB1 and DPB1 alleles by PCR and SSOPH typing and for DOB polymorphism by RFLP. HLA-DRB1 alleles, in paired MLR responses between unrelated individuals indicated that matching of HLA-DRB1 was a better predictor of non-reactivity than identity in HLA-DR generic types, (43% vs 22%). Moreover, 90% of the DRB1 matched pairs had nonreactive and weakly reactive MLR, whereas only 37% of DRB1 mismatched unrelated individuals gave weak or no reactions. Matching for HLA-DRB1 and HLA-DPB1 alleles eliminates a significant number of cell mixtures with MLR-I reactivity. Furthermore, some DPB1 mismatches, but not all, do not seem to elicit MLR-I reactivity.  相似文献   

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Abstract: HLA-B35, a class I antigen differentially associated to several diseases in different ethnic groups, comprises at least eight alleles which differ among them by one to six amino acids. In the present work a rapid DNA typing procedure was used to investigate the distribution of the various HLA-B35 alleles in different populations. The approach is based on a group-specific PCR amplification of a set of closely related HLA-B alleles sharing a Thr in position 45 of the alpha-1 domain. The amplified DNA was then hybridized to a panel of sequence-specific oligonucleotide (SSO) probes designed to recognize the polymorphic residues in previously reported HLA-B35 subtypes. This methodology was successfully tested in 100 individuals of four different populations, previously typed by serology as HLA-B35, and in six reference panel cells of the 10th International Histocompatibility Workshop. HLA-B*3501 was the predominant subtype in all populations. B*3502, B*3503 and, to a lesser extent B*3508, were also found. Among Mexican Mestizos, thirteen individuals had patterns of SSO hybridization suggestive of new B35 alleles. The evolutionary considerations on the different B35 alleles and their extended B35, Cw4 haplotypes are discussed.  相似文献   

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Abstract: The HLA-B47, DR7 haplotype in congenital adrenal hyperplasia (CAH) due to 21–hydroxylase deficiency contains a deletion of most of the active CYP21 gene and the entire adjacent C4B gene. The C4A gene produces a protein which is electrophoretically C4A but anti-genically C4B. In the Old Order Amish, the HLA-B47. DR7 haplotype contains no deletion, but is immunologically identical to the CAH haplotype in both areas flanking the crossover region. We compared some of the genes in the MHC Class II and Class III regions in the Amish and CAH-linked haplotypes to define further the relationships between the two. The complement factor B (Bf) proteins differed, but no Bf RFLPs were identified. The complement factor 2 genes exhibited different BamHI RFLPs. Analyses of the tumor necrosis factor-α genes revealed the same Ncol restriction patterns. The RD genes contained microsatellites of the same size. Portions of the MHC Class II DR and DQ , and Class III CYP21 and C4 alleles were sequenced. The exon 2 sequences of DQ2 and DR7 were identical in the two haplotypes. In the Amish haplotype, both CYP21 and C4 gene pairs were present and functionally normal. The CAH haplotype had two sequence crossovers: from CYP21P to CYP21 in the 7th intron, and from C4A to C4B between codons 1106 (exon 26) and 1157 (exon 28). A model is proposed which accounts for the CAH-linked mutant haplotype arising from a nonmutant homologue via three crossings-over.  相似文献   

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Abstract: Many new HLA-C locus alleles have recently been identified by DNA sequencing, and a molecular based method for their detection using PCR with sequence specific primers has been reported. However, other methods may be more appropriate for the identification of C locus alleles in larger studies. Here we describe one such system, based on PCR sequence specific oligonucleotide probes, (SSOP) for C locus typing. Advantages of SSOP typing compared to SSP are that it is easier to detect new alleles, more cost effective and less time consuming. We have developed a DNA typing method to identify the broad C locus antigens (including those not yet defined serologically) using a minimum of probes with one amplification. We use a C locus specific sense primer in exon 2 and a consensus antisense primer in exon 3, in a two-step PCR, giving a product of 710 bp. Probes were designed with similar melting temperatures (54–56C) that would identify as many alleles as possible. The method was established using DNA from B lymphoid cell lines of known C locus type, mostly 10th workshop homozygous cell lines, plus as many other sequenced cell lines as possible. The system was able to correctly identify their C locus types using only 26 probes. DNA was tested from a panel of serologically typed individuals which included many different heterozygous combinations. We found a high concordance of results, with all discrepancies being additional antigens identified by molecular typing, filling in serological blanks. We can identify all common heterozygote combinations using this method.  相似文献   

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The prevalence of the Taq I(-) allele in variants of α1-proteinase inhibitor (α1PI) was investigated in a group of 28 black asthmatic patients and 32 black control individuals, and was compared to 43 white asthmatic patients and 32 white control individuals. The plasma concentration of α1PI was determined in eight black and 14 white asthmatics without the Taq I(-) allele, and compared to seven black and three white asthmatics with the Taq I(-) allele. Alpha-1-PI concentration was also determined in 10 black and 29 white control individuals without the Taq I(-) allele and compared to seven black and three white controls with the Taq I(-) allele. There was a highly significant difference in the frequency of the Taq I(-) allele between black South Africans (24.1%) and white South Africans (6%) (p<0.00001) and a significant difference in the frequency of the Taq I(-) allele between black asthmatics and white asthmatics (p = 0.0004) and between black controls and white controls (p = 0.011). The Taq I(-) allele was significantly associated with the Ml(Val213) variant as compared to the Ml (Ala213) of α1PI (p = 0.0042). There was no difference in the concentration of α1PI between the asthmatics (black and white) lacking the Taq I(-) allele and the asthmatics (black and white) with the allele. However, a significant increase in plasma α1PI concentration was found in the asthmatics compared to the controls (p = 0.011). The Taq I(-) allele did not seem to interfere with the basal expression of α1PI in the groups of asthmatic patients in this study.  相似文献   

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Clinical findings on three closely related, severely malformed infants and a 20-week-old fetus with an identical partial trisomy of chromosome 1 (1q42→ter) have made possible the delineation of a new syndrome. The typical manifestations of this syndrome are: severe intrauterine and postnatal developmental retardation, trigonocephaly with wide sutures and fontanels, characteristic facial features, colobomata of the iris, small hands and feet, and early death.  相似文献   

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SUMMARY  Sleep and wakefulness were studied in rats following administration of a selective 5-HT1A agonist (8-OH-DPAT), a non-selective 5-HT1A antagonist [(-) pindolol] and a combination of 8-OH-DPAT and (—) pindolol.
8-OH-DPAT (1.0–4.0 μg) injected into the dorsal raphe nucleus increased slow-wave sleep and decreased wakefulness. Administration of the 5-HT1A agonist by subcutaneous route induced biphasic effects such that low doses (0.010 mg kg-1) decreased wakefulness and increased slow-wave sleep while higher doses (0.375 mg kg-1) induced opposite effects. REM sleep was suppressed and REM latency was increased, what could be tentatively ascribed to a non-specific effect (hypothermia). (-) Pindolol (1.0–4.0 mg kg-1) induced an initial increase of wakefulness and a decrease of NREM sleep and REM sleep. Thereafter, NREM sleep showed a marked increase while REM sleep remained depressed. Pretreat-ment with (—) pindolol reversed the effects of both small and large doses of 8-OH-DPAT on slow-wave sleep and wakefulness.
The opposite effects, observed on the waking EEG after activation of either serotonin autoreceptors or postsynaptic 5-HT1A receptors with adequate doses of 8-OH-DPAT, tend to indicate an active role for the 5-HT1A receptor in the control of the waking state.  相似文献   

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X-linked spinal and bulbar muscular atrophy (SBMA) occurs due to an expansion of the trinucleotide repeat (CAG)n in the androgen receptor gene. Anticipation is relatively rare in SBMA in contrast to spinocerebellar ataxia type 1 (SCA1), and dentatorubral and pallidoluysian atrophy (DRPLA) which show obvious paternal anticipation. The differences in the CAG repeat number were compared among sperm, leukocytes and skeletal muscles of SBMA patients. In SBMA, the sperm of most patients and the skeletal muscle of all patients showed the same repeat number as their leukocytes, whereas the increase in the repeat number from leukocytes to sperm was evident in SCA1 and DRPLA patients. The higher mosaicism level in sperm compared with leukocytes was common in SBMA, SCA1 and DRPLA, and the level of sperm was lower in SBMA than in SCA1 and DRPLA. Thus, spermatogenesis was suggested to be strongly associated with paternal anticipation. The mosaicism level was smaller in SBMA than in other (CAG)n expanded disorders, and smallest in the SBMA carrier females. These findings demonstrate that the CAG repeat in SBMA is relatively stable in mitotic and meiotic processes, and there is a possibility that the lower mosaicism level of the carrier females compared with the SBMA patients is associated with X-linked recessive inheritance.  相似文献   

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Swimming movements in the leech and lamprey are highly analogous, and lack homology. Thus, similarities in mechanisms must arise from convergent evolution rather than from common ancestry. Despite over 40 years of parallel investigations into this annelid and primitive vertebrate, a close comparison of the approaches and results of this research is lacking. The present review evaluates the neural mechanisms underlying swimming in these two animals and describes the many similarities that provide intriguing examples of convergent evolution. Specifically, we discuss swim initiation, maintenance and termination, isolated nervous system preparations, neural-circuitry, central oscillators, intersegmental coupling, phase lags, cycle periods and sensory feedback. Comparative studies between species highlight mechanisms that optimize behavior and allow us a broader understanding of nervous system function.  相似文献   

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Renal dysplasia and asplenia in two sibs   总被引:2,自引:0,他引:2  
A family is reported in which two sibs, one male and the other female, both died within 24 hours of birth with enlarged polycystic kidneys. Postmortem histology in the second child showed gross renal dysplasia. In both children the pancreas was enlarged, nodular and cystic but the liver appeared macroscopically normal. In the second child, histological examination confirmed pancreatic fibrosis with cystic dilation of ducts, but showed portal fibrosis with bile duct proliferation in the liver.
This combination of findings is very reminiscent of those in a girl and her brother reported by Ivemark et al. (1959). The children reported here also showed absence or hypoplasia of the spleen, cardiac anomalies and other features of the Ivemark syndrome (Ivemark 1955), a quite different, usually sporadic, congenital disorder. It is suggested that the children described here have a distinct lethal congenital disorder, probably inherited in an autosomal recessive manner.  相似文献   

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Over 200 schizophrenic patients belonging to three major and interrelated pedigree complexes have been investigated over the past 30 years in a North Swedish geographically isolated population, presently numbering about 6,000. An intensive investigation of a number of biochemical correlates and genetic markers in a few selected families belonging to one of the major pedigrees has indicated new strategies for the current research program.
Schizophrenia, as defined operationally, is significantly associated with decreased activities of two enzymes (1) blood platelet monoamine oxidase, (2) plasma dopamine-β-hydroxylase, and (3) with the genetic marker Gc2 (group specific antigen). Both enzymes are subject to genetic variation. A positive score for linkage between schizophrenia and low plasma DBH activity has been calculated, but, so far, available data are insufficient for discrimination between linkage and partial contribution of genetically controlled low plasma DBH to the pathogenesis of the disease. Alternatively, both mechanisms could be involved.
As a model for continued research, schizophrenia is explained as based on a double dominant-recessive genotype (Aabb), representing a vulnerability which in about 50 % of cases develops into clinical schizophrenia. It is suggested that the dominant mutation (A) operates on or affects MAO activity, and that the recessive genotype (bb) is instrumental in low variates of DBH activity and very likely such variates within the normal range of physiological variation. Moreover, it is suggested that the combined effects of MAO- and DBH-reduced efficiency on the metabolism of e.g. dopamine could be an essential pathogenic mechanism for the schizophrenic illness which is segregating in this population.  相似文献   

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About 1900, modern food selection and processing caused widespread epidemics of the B vitamin deficiency diseases of beriberi and pellagra which, for genetic reasons, often expressed as different diseases ranging from bowel and heart disease to dermatoses and psychoses. But the B vitamins merely help convert essential fatty acids (EFA) into the prostaglandin (PG) tissue regulators and it now turns out that, through hydrogenation, milling and selection of w3-poor southern foods, we have also been systematically depleting, by as much as 90%, a newly discovered trace Nordic EFA (w3) of special importance to primates and sole precursor of the PG3(4) series, even as a concurrent fiber deficiency increases body demand for EFA. Since substrate EFA is processed by many B vitamin catalysts, an EFA deficiency will mimic a panhypovitaminosis B, i.e., a mixture of substrate beriberi and substrate pellagra resembling vitamin beriberi and pellagra but exhibiting as even more diverse endemic disease. This would consitute a second stage of the Modern Malnutrition and explain why some workers now hold the dominant diseases of modermized societies to be new, nutritionally based, pellagraform yet lipid-related and to range, once again, from heart disease to psychosis. It is an assumption that our dominant diseases are unrelated to each other or are merely revealed by our diagnostic acumen and therapeutic success; and that hydrogenating millions of tons of food oils annually, to destroy the rancidity producing w3-EFA, is safe for primates. Extensive beriberiform disease is reported here in 32 typical cases taken from medical practice which responds strikingly to linseed oil supplements (60% w3-EFA) in confirmation of identical results in Capuchins.  相似文献   

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There are an estimated over 200 million yearly cases of malaria worldwide. Despite concerted international effort to combat the disease, it still causes approximately half a million deaths every year, the majority of which are young children with Plasmodium falciparum infection in sub-Saharan Africa. Successes are largely attributed to malaria prevention strategies, such as insecticide-treated mosquito nets and indoor spraying, as well as improved access to existing treatments. One important hurdle to new approaches for the treatment and prevention of malaria is our limited understanding of the biology of Plasmodium infection and its complex interaction with the immune system of its human host. Therefore, the elimination of malaria in Africa not only relies on existing tools to reduce malaria burden, but also requires fundamental research to develop innovative approaches. Here, we summarize our discoveries from investigations of ethnic groups of West Africa who have different susceptibility to malaria.  相似文献   

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Newton H 《Medical history》2011,55(2):153-182
Sick children were ubiquitous in early modern England, and yet they have received very little attention from historians. Taking the elusive perspective of the child, this article explores the physical, emotional, and spiritual experience of illness in England between approximately 1580 and 1720. What was it like being ill and suffering pain? How did the young respond emotionally to the anticipation of death? It is argued that children’s experiences were characterised by profound ambivalence: illness could be terrifying and distressing, but also a source of emotional and spiritual fulfilment and joy. This interpretation challenges the common assumption amongst medical historians that the experiences of early modern patients were utterly miserable. It also sheds light on children’s emotional feelings for their parents, a subject often overlooked in the historiography of childhood. The primary sources used in this article include diaries, autobiographies, letters, the biographies of pious children, printed possession cases, doctors’ casebooks, and theological treatises concerning the afterlife.  相似文献   

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