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11.
The Charcot-Mane-Tooth disease type 1A (CMTlA) phenotype is most often associated with a 1.5 megabase (mb), tandem duplication of chromosome 17 band p12 (17˜12). The prevailing hypothesis is that the demyelinating neuropathy results from a dosage effect of the peripheral myelin protein gene PMP22 which is included within this duplication. We present a patient with clinical and electrophysiological features ofCMTlA in whom an extra PMP22 gene resulted from a rare unbalanced translocation of 17p to the X chromosome. This finding further supports the hypothesis of gene dosage as the basis for CMTlA. More-over, this case highlights the importance of fluorescence in siiu hybridization (FISH) as an alternative molecular technique in the diagnosis of CMTlA. 相似文献
12.
Immune-stimulating complexes containing Quil A and protein antigen prime class I MHC-restricted T lymphocytes in vivo and are immunogenic by the oral route 总被引:7,自引:0,他引:7 下载免费PDF全文
Induction of all forms of protective immunity by oral immunization with subunit vaccines is an ideal goal for the development of novel vaccines, but creates several theoretical problems from the point of view of antigen processing mechanisms. We show here that incorporation of the protein antigen ovalbumin (OVA) in lipophilic immune-stimulating complexes (ISCOMS) induces very strong primary immune responses in mice and requires very small amounts of antigen. OVA ISCOMS were particularly efficient at stimulating T-cell-mediated immunity in vivo, including delayed-type hypersensitivity (DTH) and potent class I major histocompatibility complex (MHC)-restricted cytotoxic T-cell responses. Furthermore, unlike native protein, OVA in ISCOMS was immunogenic when given orally. Thus, ISCOMS seem to allow protein to enter both the endogenous and exogenous pathways of antigen processing and overcome the usual induction of tolerance after feeding antigen. ISCOMS could provide potentially useful adjuvants for the development of oral subunit vaccines. 相似文献
13.
Moredun Bordetella Medium, an improved selective medium for isolation of Bordetella parapertussis. 下载免费PDF全文
Bordetella parapertussis, previously thought to be an obligate human respiratory tract pathogen, has been isolated from sheep. Attempts to assess the prevalence of B. parapertussis in conventionally reared sheep by nasal swabbing proved futile with existing selective media because of extensive overgrowth with Mucor spp. and other nasal commensals. Moredun Bordetella Medium (MBM), which contains cycloheximide and spectinomycin at final concentrations of 0.5 mg/ml and 100 mu g/ml, respectively, was developed as an improved selective medium to isolate B. parapertussis from the nasal cavities of conventionally reared sheep. The selective ability of MBM was evaluated with 200 nasal swabs from conventionally reared sheep, and B. parapertussis was recovered from 31.5% of the samples. MBM facilitated the simple and effective isolation of B. parapertussis from ovine nasal swabs and, in successfully excluding overgrowth with other contaminants, proved superior to other test formulations evaluated and to existing conventional media. 相似文献
14.
The role of antigen-presenting cells and interleukin-12 in the priming of antigen-specific CD4+ T cells by immune stimulating complexes 总被引:5,自引:0,他引:5
Immune stimulating complexes (ISCOMs) containing the saponin adjuvant Quil A are vaccine adjuvants that promote a wide range of immune responses in vivo, including delayed-type hypersensitivity (DTH) and the secretion of both T helper 1 (Th1) and Th2 cytokines. However, the antigen-presenting cell (APC) responsible for the induction of these responses has not been characterized. Here we have investigated the role of dendritic cells (DC), macrophages (Mφ) and B cells in the priming of antigen-specific CD4+ T cells in vitro by ISCOMs containing ovalbumin (OVA). OVA ISCOMs pulsed bone marrow (BM)-derived DC but not BM Mφ, nor naïve B cells prime resting antigen-specific CD4+ T cells, and this response is greatly enhanced if DC are activated with lipopolysaccharide (LPS). Of the APC found in the spleen, only DC had the capacity to prime resting antigen specific CD4+ T cells following exposure to OVA ISCOMs in vitro, while Mφ and B cells were ineffective. DC, but not B cells purified from the draining lymph nodes of mice immunized with OVA ISCOMs also primed resting antigen-specific CD4+ T cells in vitro, suggesting that DC are also critical in vivo. Using DC and T cells from interleukin (IL)-12 p40−/− mice, we also identified a crucial role for IL-12 in the priming of optimal CD4+ T cell responses by OVA ISCOMs. We suggest that DC are the principal APC responsible for the priming of CD4+ T cells by ISCOMs in vivo and that directed targeting of these vectors to DC may enhance their efficancy as vaccine adjuvants. 相似文献
15.
The infrapyloric artery and cephalic pancreatoduodenectomy with pylorus preservation: preliminary study 总被引:1,自引:0,他引:1
Ph Wind JM Chevallier JJ Sarcy V Delmas PH Cugnenc 《Surgical and radiologic anatomy : SRA》1994,16(2):165-172
Summary Cephalic pancreatoduodenectomy (CPD) with pylorus preservation has been suggested to improve the functional and nutritional result of surgery. At operation, the first two centimeters of the duodenum are preserved, the vascular arch of the lesser gastric curvature is saved and the right gastroepiploic artery is resected at its origin. The aim of this study on 15 fresh cadavers was to determine the origin of the vascularization of the remaining duodenum and also the possibilities of preserving an optimal vascularization after CPD and pylorus preservation. All of the arteries supplying the remaining duodenum and arising either from the right gastric artery or the right gastroepiploic artery were identified. The distances between the origin of the infrapyloric artery and the termination of the gastroduodenal artery on the cranial and ventral pancreaticoduodenal artery and the left gastroepiploic artery were measured. At CPD with pylorus preservation, the study demonstrated that: 1) the cranial side of the remaining duodenum remains vascularized in 80% of the cases by one or two supraduodenal branches coming from the right gastric artery; 2) ligation of the right gastroepiploic artery eliminates all vascular supply to the caudal side of the remaining duodenum in almost half of the cases; 3) in these cases, the dissection of the bifurcation of the gastroduodenal artery and the vascular section beyond the origin of the infrapyloric artery allowed a direct vascular supply to the remaining duodenum to be preserved.This work was presented at the French Section of the European Association of Clinical Anatomy meeting, Bobigny, France, 1992 相似文献
16.
17.
The localisation of the principal blood group antigens has been studied in human liver. These blood group antigens included the erythrocyte antigens and the antigen of the major histocompatibility complex. This study was performed by the indirect immunofluorescence technique using polyclonal antibodies of human or animal origin and monoclonal antibodies from hybridomas. This study has shown that the normal hepatocyte is lacking in blood group antigens. On the contrary, the biliary cell was rich in antigenic markers: the main antigens expressed were Lewis, Pr, HLA-A and B antigens. In Kupffer cells, only i and HLA-DR antigens were clearly expressed. The endothelial cells of blood vessels mainly show A, B, H, HLA-A and B antigens; HLA-DR and Pr are slightly expressed. HLA-DR antigens were more strongly expressed on veins than on arteries. Dendritic cells have been identified in the portal space of human liver. They bore i and HLA-DR antigens. 相似文献
18.
Estimation of the genetic contribution of presenilin-1 and -2 mutations in a population-based study of presenile Alzheimer disease 总被引:11,自引:4,他引:11
Cruts M; van Duijn CM; Backhovens H; Van den Broeck M; Wehnert A; Serneels S; Sherrington R; Hutton M; Hardy J; St George-Hyslop PH; Hofman A; Van Broeckhoven C 《Human molecular genetics》1998,7(1):43-51
Two closely related genes, the presenilins ( PS ), located at chromosomes
14q24.3 and 1q42.1, have been identified for autosomal dominant Alzheimer
disease (AD) with onset age below 65 years (presenile AD). We performed a
systematic mutation analysis of all coding and 5'-non-coding exons of PS -1
and PS -2 in a population-based epidemiological series of 101 unrelated
familial and sporadic presenile AD cases. The familial cases included 10
patients of autosomal dominant AD families sampled for linkage analysis
studies. In all patients mutations in the amyloid precursor protein gene (
APP ) had previously been excluded. Four different PS -1 missense mutations
were identified in six familial cases, two of which where autosomal
dominant cases. Three mutations resulted in onset ages above 55 years, with
one segregating in an autosomal dominant family with mean onset age 64
years (range 50-78 years). One PS -2 mutation was identified in a sporadic
case with onset age 62 years. Our mutation data provided estimates for PS
-1 and PS -2 mutation frequencies in presenile AD of 6 and 1% respectively.
When family history was accounted for mutation frequencies for PS -1 were
9% in familial cases and 18% in autosomal dominant cases. Further,
polymorphisms were detected in the promoter and the 5'-non-coding region of
PS -1 and in intronic and exonic sequences of PS -2 that will be useful in
genetic association studies.
相似文献
19.
Genetic control of eosinophilia. Mouse strain variation in response to antigens of parasite origin 总被引:3,自引:1,他引:3 下载免费PDF全文
Strain variation in capacity to develop peripheral blood eosinophilia was observed in inbred NIH and C57BL/10 (B10) mice exposed to parasite antigens by infection or by parenteral injection in Freund's complete adjuvant. NIH mice were good responders, showing rapid development of high eosinophil counts, B10 mice were low responders. The difference in response phenotype was independent of the parasite used for infection (Trichinella spiralis or Nematospiroides dubius) and of the antigen used for injection (T. spiralis larval antigen or Limulus haemocyanin). Pre-treatment of T. spiralis infected mice with low doses of cyclophosphamide (150 mg/kg) or restriction of the duration of infection to 7 days by anthelmintic treatment did not enhance the response of B10 mice. Thus no evidence was found that the poor response phenotype of B10 during T. spiralis infection reflected any active suppressive mechanisms developed during the adult or muscle larval phases of infection. Demonstration that eosinophilia is induced primarily by the intestinal phase allows comparison with other parameters of the immune response induced by the adult worms, namely intestinal mastocytosis and worm expulsion. From this comparison it is concluded that the low eosinophil response phenotype of B10 mice may reflect a generalized deficiency in the response of bone marrow derived precursor cells to factors of T lymphocyte origin. The significance of genetically determined variation in eosinophil responsiveness is discussed in relation to the development of protective immune or pathological responses to parasite infection. 相似文献
20.
All citizens (N = 22066) aged 16 to 65 of a medium-sized Belgiantown were personally invited to CPR training sessions held intheir neighbourhood. 1152 responded by attending a trainingsession. Those who did not so respond were surveyed (randomsample N=600) for reasons of their not coming. The sample fittedwell with census data for gender, age and suburb location butnot for job, because retired persons and women at home wereover represented. 123 persons did not want to answer the questions. 116 personssaid they were already trained in CPR, 276 said they would accepton a future occasion and 82 said they would not. Three personsdid not answer this question. There was no discrimination for job, gender and suburb locationbetween those who did and did not accept a future training opportunity,nor was the existence of a heart patient among relatives. Theolder the person, the less inclined was that person to participatein CPR training (age effect x2 = 17.17, d.f. = 9, P<0.05).The 276 who accepted future training, chose their workplace(221) and/or their social meeting place (club etc.) as the placewhere this future training should be held. We suggest that CPR training is well accepted and that the trainingopportunities should be given at places of work and social gatherings. 相似文献