Neues und Bewährtes in der Kinderchirurgie

Zusammenfassung Die in den letzten 25 Jahren erzielten Fortschritte der Kinderchirurgie werden vor allem in der Anwendung der Ergebnisse der Grundlagenforschung, in neuen Untersuchungsverfahren, wie der Sonographie und der Computertomographie, sowie in der zunehmenden klinischen Erfahrung mit, entsprechender Adaptierung der Operationsmethoden gesehen. Dafür werden einige, für die Praxis relevante Beispiele angeführt.      

紫外线减毒尾蚴活疫苗预防小鼠日本血吸虫感染有效免疫期的实验研究

以 400μW/(min·cm~2)剂量紫外线照射减毒日本血吸虫尾蚴, 1 次免疫小鼠(200条/只)可产生抗日本血吸虫感染的免疫能力。这种免疫力至少可维持7个月。1、3、5、7个月各组中,免疫组与攻击组虫荷均数比较,差异均有显著性意义。1、3、5和7个月所获减虫率分别为71.28％、69.63％、62.26％和46.16％,7个月与1、3、5个月比较,差异有显著性意义,提示7个月时小鼠抗日本血吸虫的免疫力可能有所下降。     

Amplified fragment length polymorphism analysis of the VNTR locus D1S80 in central Spain

Summary The polymorphism of the D1S80 locus has been analyzed in a population sample of 203 unrelated individuals living in Madrid (central Spain) by PCR and subsequent semi-dry discontinuous polyacrylamide gel electrophoresis (Tris-chloride/Tris-glycine buffer system) followed by silver staining, The electrophoretic system described in this study offers high resolution in the separation of the different D1S80 alleles allowing the detection of microvariability around the allele T22 in the spanish population. Twenty different alleles containing 17–40 repeats of the basic 16bp unit were distinguished. The alleles T18 and T24 were found to be relatively common in Spain, as in other populations:, with frequencies of 0.224 and 0.372, respectively. No evidence of significant deviations from Hardy-Weinberg equilibrium was found in these preliminary population data.     

T载体克隆乙肝病毒preS2+S基因的实验研究

将商品化真核表达载体pcDNA3改造成T载体pcDNA3－T，并运用pcDNA3－T直接克隆了由PCR扩增的adw2亚型乙肝病毒preS2与S基因。结果：pcDNA3－T与PCR产物的重组率高达70％。提示：该方法具有简便，省时等特点。     

Overexpression of S100A4 is closely related to the aggressiveness of gastric cancer

Elevated levels of the calcium-binding protein S100A4 cause metastasis of benign rat mammary tumor cells. To investigate whether S100A4 plays an important role in the invasion and metastasis of gastric cancers, we examined the gene mutations in the coding regions and expression patterns of the S100A4 in gastric adenocarcinoma in Korea. Moderate to strong expression of S100A4 was found in 53 (68.8%) of the 77 gastric adenocarcinomas, whilst normal gastric epithelium either failed to stain or showed weak staining. Interestingly, S100A4 expression was more frequently observed in gastric cancer patients with advanced gastric cancer (p=0.039), positive lymph node metastasis (p=0.001), and peritoneal dissemination (p=0.022). No gene mutations were found in the analyzed genomic area in 77 gastric adenocarcinomas and 15 gastric cancer cell lines. We found one single nucleotide polymorphism without an amino acid change, A99G, in two cases. These data suggest that the overexpression of S100A4 may be closely related to the aggressiveness of gastric cancer in Korea.     

Cytogenetic analysis in human breast tumors

Cytogenetic analysis using C-, G-, and Ag-nucleolus organizer region (NOR) staining techniques, performed on established cell lines as well as directly processed breast tumor effusions, revealed that: 1) chromosome No. 1 is involved in translocation; 2) based on 1q translocation chromosome, breast tumors could be classified into two groups; and 3) double minutes and homogeneously staining regions may be present in breast tumor cells in vivo as well as in vitro, and that homogeneously staining regions may exhibit some heterogeneity in staining.     

Origins of the projections of the superior colliculus to the dorsal lateral geniculate nucleus and the pulvinar in the rabbit

The origins of the projections of the superior colliculus to the dorsal lateral geniculate nucleus and to the pulvinar in Dutch-belted rabbits were investigated using horseradish peroxidase (HRP) methods. Following injections of HRP in the dorsal lateral geniculate nucleus, retrogradely labeled neurons were found in the upper two-thirds of the stratum griseum superficiale of the ipsilateral superior colliculus. Most of the labeled somata were spindle-shaped, and their major axes tended to be perpendicular to the surface of the superior colliculus. In contrast, following injections of the pulvinar, labeled neurons were found in the lower third of the ipsilateral stratum griseum superficiale. In these cases, the labeled somata were larger than those labeled following dorsal lateral geniculate injections and were multipolar in shape.     

Intracellular survival of persistent group A streptococci in cultured epithelial cells

Group A streptococcus (GAS) is the principle etiologic agent of bacterial pharyngotonsillitis and a wide range of other diseases. Failure to eradicate GAS from patients has been documented in 5-30% of patients with pharyngotonsillitis, in spite of the continued sensitivity of GAS to penicillin and other beta-lactams. It was recently proposed that eradication failure might be attributed to the ability of GAS to maintain an intracellular reservoir during antibiotic treatment. We have previously shown that strains derived from patients with bacterial eradication failure, despite antibiotic treatment (persistent strains), adhered to and were internalized by cultured epithelial cells more efficiently than strains that were successfully eradicated. Since, penicillin and other beta-lactams do not penetrate well into mammalian cells, intracellular survival of GAS is crucial in order to persist during prolonged antibiotic treatment. In this study, we compared the survival of GAS strains from cases of eradication failure and eradication success, using an epithelial cell culture model. We found that persistent strains show significantly increased intracellular survival, compared to the 'eradication success' strains. This finding supports the idea that an intracellular reservoir of GAS plays a role in the etiology of antibiotic eradication failure.     

Candidate genes associated with ageing and life expectancy in the Jerusalem longitudinal study

In an exploratory study, 11 common polymorphisms were examined for contributing to longevity including: apolipoprotein E (apoE), methylenetetrahydrofolate reductase (MTHFR), cathepsin D (CAD), superoxide dismutase 2 (SOD2), angiotensinogen (AGT) and insulin-like growth factor 2 (IGF2), Leiden factor 7, p53 oncogene, dopamine D4 receptor (DRD4) and the serotonin transporter (SERT). Genotype and allele frequencies of these genes were compared in 224 older (75 years) Jewish Jerusalem residents of Ashkenazi ethnicity to a group of 441 younger subjects (22 years). Nominally significant results provide suggestive evidence in the Ashkenazi group that apoE, MHTFR, SOD2, IGF2 ApaI, and factor VII are risk factors for a single outcome, survival to 75. Overall, the more genetically homogenous Ashkenazi ethnic group showed evidence for association in five genes examined suggesting that future studies in this population would gainfully focus on this ethnic group.