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21.
钩体基因疫苗对豚鼠延髓原癌基因表达的影响   总被引:1,自引:1,他引:0  
张燕华  李峻 《华西医学》1998,13(2):166-169
我们的研究已表明,赖型017株钩体外膜疏水蛋白OmpL39是稳定的免疫原,在此我们分别用OmpL39与钩体死菌苗和生理盐水对照免疫豚鼠,研究OmpL39的免疫保护作用和免疫机理,对OmpL39的抗原特异性刺激引起中枢原癌基因(Cfos基因)表达进行了观察。结果表明,OmpL39在豚鼠体内能产生高效价的阳性抗体,免疫保护率为100%。在OmpL39对中枢Cfos基因表达的影响中,我们观察到OmpL39免疫的豚鼠较空白和死菌苗组Cfos表达明显少于死菌苗组和空白对照组(p<005)。提示OmpL39能特异性地抑制Cfos基因的表达,减轻强毒钩体对动物体内的病理损伤,有较死菌苗强的免疫保护作用。  相似文献   
22.
Mutations in the dysferlin gene (DYSF) on chromosome 2p13 cause distinct phenotypes of muscular dystrophy: limb-girdle muscular dystrophy type 2B (LGMD2B), Miyoshi myopathy (MM), and distal anterior compartment myopathy, which are known by the term 'dysferlinopathy'. We performed mutation analyses of DYSF in 14 Italian patients from 10 unrelated families with a deficiency of dysferlin protein below 20% of the value in normal controls by immunoblotting analysis. We identified 11 different mutations, including eight missense and three deletion mutations. Nine of them were novel mutations. We also identified a unique 6-bp insertion polymorphism within the coding region of DYSF in 15% of Italian population, which was not observed in East Asian populations. The correlation between clinical phenotype and the gene mutations was unclear, which suggested the role of additional genetic and epigenetic factors in modifying clinical symptoms.  相似文献   
23.
A multiple Robertsonian fission chromosomal race of the Liolaemus monticola complex in Chile is described and is shown to be the most derived and the most complex among the Liolaemus examined thus far. The 29 karyotyped lizards analysed from the locality of Mina Hierro Viejo, Petorca, Provincia de ValparaUso, Chile, exhibited a diploid chromosomal number ranging from 42 to 44, and several polymorphisms. The polymorphisms included: a pair 1 fission; a pair 2 fission plus a pericentric inversion in one of the fission products, which moved the NOR and satellite from the tip of the long arm of the metacentric 2 to the short arm of the fission product; a fission in pair 3; a polymorphism for an enlarged chromosome pair 6; and a polymorphism for a pericentric inversion in pair 7. This population is fixed for a fission of chromosome pair 4. A total of 76% of the lizards analysed were polymorphic for one or more pairs of chromosomes. We have compared these data with other Liolaemus monticola chromosomal races and calculated the Hardy–Weinberg ratios for the polymorphic chromosome pairs in this Multiple-Fission race. Karyotypic differences between the Northern (2n = 38–40) and the Multiple-Fission (2n = 42–44) races were attributed mainly to Robertsonian fissions, an enlarged chromosome and pericentric inversions involving the macrochromosomes and one microchromosome pair.  相似文献   
24.
BACKGROUND.: There is agreement that a family history of hypertension (HT),is a predictor for the risk of diabetic nephropathy (DN) inpatients with type 2 diabetes, and possibly also type 1 diabetes.It follows that genes related to the risk of hypertension mustalso be considered candidate genes for DN. The 235T allele ofthe angiotensinogen gene was found to be related to primaryHT. METHODS.: To examine whether it is predictive for DN as well, we examinedthe angiotensinogen gene polymorphism in 230 healthy local controls,423 patients with type 1 diabetes (n=180 with DN; n=243 withoutDN) and 663 patients with type 2 diabetes (n=310 with DN; n=353without DN). The angiotensinogen gene M235T polymorphism wasdetermined using PCR amplification. RESULTS.: The following results were obtained (i) no significant differenceof genotype distribution (type 1: MM/MT/TT(%) 27.6/57.2/15.2vs. 27.2/56.1/16.7 (P=0.92); type 2: MM/MT/TT (%) 31.7/48.2/20.1vs. 32.9/46.8/20.3 (P=0.93)) or allele frequencies (type 1:M 0.56 vs. 0.55 (P=0.795); type 2: M 0.56 vs. 0.56 (P=0.86))was found, between diabetic patients with or without DN, (ii)no difference was found between normotensive and hypertensivediabetic patients. CONCLUSION.: The data argue against a role of the angiotensinogen gene M235Tpolymorphism in the manifestation of diabetic nephropathy orhypertension in diabetic patients.  相似文献   
25.
Renal transplantation experiments have shown that the kidney contributes to chronic sympathectomy-induced arterial pressure reduction in spontaneously hypertensive rats (SHR). The underlying mechanisms are currently unclear but may include alterations in the function of small renal arteries. Neonatal SHR were sympathectomized by intraperitoneal guanethidine injections and removal of adrenal medullary tissue. Controls were sham- or hydralazine-treated. At 12 weeks of age, distal interlobar artery segments were investigated using small-vessel wire myography. Vessels from sympathectomized animals showed increased sensitivity to noradrenaline (NE). Vasopressin- and endothelin-1-induced vasoconstriction was similar in all groups (as reflected by the pD2, i.e. –logEC50, where EC50 is the molar concentration of agonist eliciting a half-maximal response). Maximum vasopressin-induced tension was similar in all groups while endothelin-1-induced maximum tension was significantly higher in sympathectomized than in sham-treated SHR. The sensitivity of NE-induced vasoconstriction to extracellular Ca2+ did not differ between groups while sensitivity to L-type Ca2+ channel activation was significantly higher in both sympathectomized and hydralazine-treated animals than in sham-treated animals. Endothelium-dependent and independent vasodilation were similar in all groups. Sequential blockade of NO-synthase and cyclooxygenase had similar effects in all groups. In conclusion, neonatal sympathectomy does not induce any changes in the function of isolated proximal renal resistance arteries from SHR that could explain the blood pressure lowering effect of a kidney graft from sympathectomized SHR.  相似文献   
26.
Summary We have identified a polymorphic 9-bp repeat sequence in exon 1 of thehMSH3 gene using polymerase chain reaction (PCR). Five alleles were observed in unrelated Japanese individuals with heterozygosity of 0.57.  相似文献   
27.
The genetic polymorphism of orosomucoid (ORM) and alpha-2-HS-glycoprotein (AHSG) were studied in Thai, Sri Lankan and Paraguayan populations using isoelectric focusing. Gene frequencies in these populations were compared with those in other populations. Four new ORM variants were detected:ORM1 * 15 in Thai,ORM1 * 16 in Paraguayan,ORM2 * 21 andORM2 * 22 in Sri Lankan.  相似文献   
28.
Eighty-five young Mauritian Indians, male survivors of premature myocardial infarction (MI) and thus belonging to a high risk group, were compared with 108 stringently selected controls for a possible association between premature MI and an insertion/deletion (I/D) polymorphism in the gene encoding angiotensin I-converting enzyme (ACE). The frequency of the D allele was 0.42 in the MI group and 0.43 in the control group, and thus no association between I/D polymorphism of ACE with susceptibility to early-onset MI was found in this population group. Other gene components of the renin-angiotensin system and lipid metabolism need to be explored to understand the genetic factors involved in causing MI at an early age.  相似文献   
29.
A previous limited study demonstrated that Mycobacterium tuberculosis isolates with a mutation at amino-acid position 315 of katG (Delta315) exhibited high-level resistance to isoniazid and were more frequently resistant to streptomycin. In the present study, isoniazid-resistant M. tuberculosis isolates from 8,332 patients in The Netherlands (1993-2002) were screened for the Delta315 mutation. Isoniazid resistance was found in 592 (7%) isolates, of which 323 (55%) carried Delta315. IS6110 restriction fragment length polymorphism analysis showed that Delta315 isolates occurred in clusters, suggesting recent transmission, at the same frequency as isoniazid-susceptible isolates. In contrast, other isoniazid-resistant isolates clustered significantly less frequently. Delta315 isolates were high-level isoniazid-resistant, streptomycin-resistant and multidrug-resistant significantly more often, and may have a greater impact on public health, than other isoniazid-resistant isolates.  相似文献   
30.
The HLA-DRB1 and -DQB1 alleles in 161 healthy unrelated individuals, including Caucasians, Blacks and Mulattos (mixed Caucasian and Black), from the Northeastern region of the state of S?o Paulo, Brazil were analysed. The 36 different DRB1 alleles detected included not only common Caucasian alleles, but also DRB1*0411, 0807 and 1402, typical of Amerindians, and DRB1*0302, 1503, and 0804, typical of African American Blacks.  相似文献   
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