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171.
The hereditary pancreatitis gene maps to long arm of chromosome 7   总被引:11,自引:0,他引:11  
Hereditary pancreatitis (HP) is an autosomal dominant disorder with incomplete penetrance characterized by recurring episodes of severe abdominal pain often presenting in childhood. Although this disorder has only been recently described, about 100 families have been documented worldwide. The pathophysiology of this disorder is unknown. Here, a large French family of 147 individuals (47 of whom were affected) from a four-generation kindred with HP has been examined and a genome segregation analysis of highly informative microsatellite markers has been performed. Linkage has been found between HP and six chromosome 7q markers. Maximal two point lod scores between HP and D7S 640, D7S 495, D7S 684, D7S 661, D7S 676 and D7S 688 were 4.00 (theta = 0.143), 5.85 (theta = 0.143), 4.91 (theta = 0.156), 8.58 (theta = 0.077), 8.28 (theta = 0.060), 4.40 (theta = 0.169), respectively. Multipoint linkage data combined with recombinant haplotype analysis indicated that the most likely order is: D7S 640-D7S 495-D7S 684-D7S 661-D7S 676-D7S 688, with the HP gene situated in the underlined region. As in all families reported in the literature, the clinical presentation of the disease is identical to the presentation of sporadic cases, one could expect that the knowledge of the HP gene could be a clue to pancreatitis in general. Based on its map position, this is the first step towards the positional cloning of the Hereditary Pancreatitis Gene (HPG).   相似文献   
172.
The Werner's syndrome (WS) is a rare recessive disease characterized by an early onset of geriatric disorders. The Werner's syndrome gene (WRN) recently cloned, encodes for an helicase and therefore plays a role in DNA metabolism and DNA repair. Here, we report the study of a French family with two affected members and numerous cancers. Using the protein truncation test and sequencing, we identified a homozygous mutation in the WRN gene. This mutation generates a frame shift leading to a very short 391 amino acids truncated protein without the helicase motif. A particularly severe phenotype of the affected patient was associated with an unusual vulvar cancer traditionaly observed in elderly patients and therefore likely to be related to the Werner's syndrome. An additional substitution of G for A at nucleotidic position 1392 was also described. We suggest that a relation between genotype and phenotype could exist in the studied family.  相似文献   
173.
Killer cell immunoglobulin-like receptors (KIRs) belong to a diverse family of natural killer (NK) cell receptors recognizing human leukocyte antigen (HLA) class I molecules. Due to this functional link, KIR molecules are expected to display a high polymorphism, such as their HLA ligands. Moreover, many studies conducted in mouse and human models have shown that NK-KIR receptors play an important role in haematopoietic stem cell transplantation (HSCT). A beneficial impact of peculiar KIR ligand (HLA) mismatching has been reported suggesting a role to this combinatory HLA-KIR polymorphism. It is thus important to investigate KIR diversity in various human populations. To this end, we used polymerase chain reaction-sequence-specific primers to evaluate KIR gene in five selected populations (France, Guadeloupe, Senegal, Finland and Réunion). Genotypic and haplotypic frequencies were computed, as well as genetic distances and dendrogram (phylip package). These data illustrate the genetic relationship of these five populations through the KIR polymorphism. Results revealed a wide diversity in KIR gene frequencies in Guadeloupe and Réunion, and a high specificity in Senegal. The obtained dendrogram indicated small genetic distances between France, Guadeloupe and Réunion as well as between France and Finland. Senegal showed a distant genetic relationship with the other countries and, interestingly, an inverted ratio of coding/non-coding (KIR2DS4/1D) alleles compared with Caucasians. These data expose the broad diversity in KIR genes worldwide and show that KIR genes are pertinent tools in human population genetics. If the role of KIR donor-recipient incompatibilities is confirmed, KIR diversity according to ethnicity should be taken into account during the selection of HSCT donors.  相似文献   
174.
NK‐cell function is regulated by a balance between inhibitory and activating killer cell immunoglobulin‐like receptors (KIR) that specifically recognize HLA class I molecules. Using KIR‐specific mAb to discriminate between KIR2DS1 and KIR2DL1 receptors, we show that KIR2DS1+ NK cells are C2‐alloreactive only from C2? individuals. Moreover, using an in vitro model of NK‐cell expansion, we show here that the frequency of KIR2DL1+ NK cells is significantly higher in the absence of C2 ligand on stimulator EBV‐B cells than in its presence. This observation was made regardless of the presence or absence of the autologous C2 ligand, suggesting that the C2? EBV‐B stimulator cells used in this in vitro model could activate unlicensed KIR2DL1+ NK cells. In the case of KIR2DL1+/S1+ genotyped individuals, KIR2DS1+ NK‐cell frequency was increased after stimulation with C2+ compared with C2? stimulator B cells, but only from C2? individuals. Altogether, these data highlight the C2 alloreactivity of KIR2DS1+ NK cells that is only observed in C2? individuals. These results provide new insights into the way in which NK KIR cell expansion might be regulated in an allogeneic environment.  相似文献   
175.
Interleukin 2 (IL-2) has been purified by a protocol using gel filtration high performance liquid chromatography (HPLC) and hydrophobic affinity chromatography with blue-trisacryl M. Peripheral blood lymphocytes or tonsillar lymphocytes were stimulated with phytohemagglutinin (PHA). Serum free conditioned medium (CM) containing IL-2, other lymphokines and residual PHA molecules was analyzed after 3 variations of ammonium sulfate (AS) precipitation: (1) precipitation of CM with 50% AS yielded a precipitate containing most of the residual PHA but also a fraction of IL-2. (2) Precipitation with direct 80% AS of crude CM yielded both IL-2 and residual PHA. (3) A double step procedure (50% AS followed by 80% AS) yielded a precipitate containing IL-2 but free of residual lectin.

HPLC purification of these various AS-precipitated materials or of lyophilized crude CM yielded 2 peaks with mitogenic activity as assayed with the CTLL2 murine clone or IL-2-dependent human Con A-stimulated lymphoblasts. IFN was easily separated from IL-2 and PHA, but BCGF still copurified with IL-2. Peak I (25 kDa) was enriched 400-fold for IL-2 while peak II (68 kDa) contained the residual PHA.

The IL-2-containing fractions eluted from HPLC were further purified by blue-trisacryl M chromatography. The IL-2 eluted with 0.4 M NaCl. The entire protocol (HPLC followed by blue-trisacryl) led routinely to 8000-fold IL-2 enrichment. Preparative HPLC directly applied to lyophilized crude (CM) enriched IL-2 activity 400-fold with yield averaging 60% of the IL-2 input. The final material was free from interferon and IL-1, but BCGF still copurified with IL-2. The 2-step purified material (HPLC and blue-trisacryl) gave 2 bands in SDS-PAGE both of which contained IL-2.  相似文献   

176.
目的探讨糖皮质激素受体(GR)和热休克蛋白90(HSP90)mRNA在糖皮质激素敏感型(SS)、依赖型(SD) 和抵抗型(SR)哮喘中的表达及其在SR哮喘发病中的作用。 方法采用反转录-聚合酶链(RT-PCR)的方法分别测定正常人(10例)、SS哮喘(10例)、SD哮喘(5例)和 SR哮喘(6例)的外周血单个核细胞(PBMC)中GR mRNA和HSP90 mRNA的表达,并在体外用IL-2、IL-4分 别、联合刺激上述细胞观察其受刺激后GR mRNA和HSP90 mRNA表达的改变情况。 结果 SR哮喘的GR和HSP90 mRNA表达水平最高(分别为0.730±0.171和1.122±0.165),SS哮喘次之 (分别为0.359±0.350和0.885±0.250),SD哮喘最低(分别为0.017±0.008和0.078±0.039)。正常人有 一定表达(分别为0.052±0.013和0.362±0.101)。GR和HSP90 mRNA的表达各组间相比P<0.05。正 常人、SS、SD和SR哮喘HSP90/GR的比值分别为7.15±1.84、8.39±7.95、5.51±3.30、1.57±0.18,SR哮喘 HSP90/GR比值明显低于前三组(P<0.05)。IL-2和IL-4单独刺激对SS、SD和SR哮喘的GR、HSP90 mRNA表达无明显影响,二者联合刺激可使SS、SD和SR哮喘GR mRNA表达以及SS、SD哮喘HSP90 mRNA 表达增强,但不能使SR哮喘HSP90 mRNA表达增强。 结论 SR哮喘中HSP90 mRNA表达相对不足造成HSP90/GR比值降低可能是SR哮喘形成的原因之一, IL-2+IL-4对GR和HSP90 mRNA表达的不同调节作用可能是形成SR哮喘HSP90/GR比值降低的原因之一。  相似文献   
177.
复方甘草片临床用法的调查报告   总被引:2,自引:0,他引:2  
郑军  赵镭  郑颖洁 《医学争鸣》2001,22(12):1088-1088
0 引言 复方甘草片是我国最常见的镇咳祛痰药 ,它疗效确切且经济实惠 ,无论从大医院到小诊所 ,都有它的踪影 .但对于它的用法 ,人们往往不太重视 ,以致于造成药物的浪费和病情的延误 .1 调查报告1.1 患者调查  1999- 10 / 12我院门诊共有 46 5例患者使用复方甘草片 ,其中长期服用此药的慢性病患者 131例 .他们根据自己的用药经验 ,一致认为复方甘草片含服效果比用水送服好 .而另外 334例急性病患者中 ,有 2 96名患者曾经用水送服复方甘草片 .问其原因 ,有 87名患者表示不知道复方甘草片应该含服 ,2 0 9名患者表示是由于复方甘草片有一…  相似文献   
178.
Decline in blood CD4+ lymphocytes during primary symptomatic infections with HIV is usually attributed to viral killing, and has not been considered in terms of altered lymphocyte migration and sequestration. We therefore sought to examine whether CD4+ cell loss from blood of macaques undergoing an acute primary SIV infection might be due to increased synthesis of cytokines, known to profoundly affect lymphocyte trafficking, rather than to direct lymphocyte destruction by virus. The findings indicate that rapid lymphocyte depletion following acute infection is not selective for CD4+ cells, correlates precisely with increased plasma IFN-gamma and tumor necrosis factor-alpha levels, and is reversible. CD4/CD8 ratios in lymph nodes with high viral burdens remain relatively unchanged despite lymphocyte loss from blood. Levels of cytokine mRNA measured in lymphoid organs reflect neither cytokine plasma levels nor their potential to induce sequestration. These results support a model of cytokine-induced lymphocyte extravasation to account for the acute HIV/SIV-induced CD4+ cell lymphopenia and raise questions regarding the extent to which altered lymphocyte migration plays a role in the gradual CD4+ cell depletion throughout infection.   相似文献   
179.
伊贝辛的分离和鉴定   总被引:3,自引:0,他引:3  
从吉林栽培的伊贝母(Fritillaria pallidiflora Schrenk)鳞茎中分离出两种介藜芦胺类生物碱Ⅰ和Ⅱ。碱Ⅱ是一个新的甾体生物碱,定名为伊贝辛(yibeissine),结构为22,26-imino-17,23-oxidojerv-12-en-6-oxo-3β,11α-diol,碱Ⅰ是一个已知化合物,结构为11-deoxo-6-oxo-5α,6-dihydrojervine。  相似文献   
180.
Loss of heterozygosity (LOH) on chromosome 9 is the most frequent genetic alteration in bladder cancer identified to date, suggesting the presence of key gene(s) for this pathology. In this study, we examined 44 bladder tumors and 21 normal bladder samples for LOH on both arms of chromosome 9. Sixteen microsatellite markers, 12 on the short arm (encompassing 9p21-22) and 4 on the long arm (encompassing 9q33-34), were chosen for their highly frequent alterations in bladder cancer. LOH for at least one marker was identified in 42 tumor samples (95.5%), and 14 tumors (32%) displayed LOH for all informative tested markers. Detailed analysis showed that 2 markers on chromosome 9p (D9S157 and D9S156) had the highest frequencies of allelic loss (about 70%), independent of tumor grade and stage. The same study was performed on the 21 normal bladder mucosa samples: 50% of informative cases presented a single specific LOH at the D9S156 locus. Normal samples showing LOH at this locus were therefore screened with 3 novel microsatellite markers in the 810-kb region incorporating D9S156. Using this marker, we found no further heterozygous loss in this region. This result allows different interpretations of the D9S156 loss in normal bladder mucosa, and suggests that D9S156 may be more an indicator of bladder epithelium impairment than a tumor-initiation marker. Similarly, this unexpected result calls in question the interpretation of LOH studies. Int. J. Cancer 77:821–824, 1998.© 1998 Wiley-Liss, Inc.  相似文献   
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