我国腹泻病患者和家畜家禽粪便标本中携带小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌的调查

目的　了解携带小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌在我国腹泻病患者粪便标本、动物粪便标本及部分食品标本中的存在情况和所致腹泻病的临床特征。方法　使用菌落原位杂交、DNA打点杂交和PCR扩增等方法。结果　在各地送检的从腹泻病患者粪便标本中分离到的、用常规方法不能鉴定的大肠杆菌中 ,均检出带有小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌菌株 ,检出率为 2 7.0 5 % (436 / 16 12 )。从市售食品标本中分离的大肠杆菌中 ,携带小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌的检出率为 10 .2 3% (9/ 88)。从家畜家禽粪便中分离的大肠杆菌中 ,携带小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌检出率为 5 .71% (16 / 2 80 )。携带小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌所致腹泻的典型临床表现为食欲不振、腹痛、寒战乏力、正常体温或低热、每日腹泻多在 6次以上、多为粘液便。结论　携带小肠结肠炎耶尔森氏菌HPI毒力岛的大肠杆菌在我国分布广泛 ,检出率高于其他几类致泻性大肠杆菌 ,对我国人民的健康是一个潜在的威胁     

淋球菌毒力岛分类及sac-4基因对淋球菌血清抗性作用的研究

目的 研究淋球菌不同基因型别的毒力岛类型及其sac-4基因与淋球菌血清抗性作用的关系.方法 运用NG-mast和正常人血清(NHS)的抗性比较试验,对46株淋球菌从分子水平上进行基因分型和毒力岛分类,并在此基础上探讨毒力岛sac-4基因与淋球菌NHS抗性之间的关系.结果 46株野生株中,GGI阳性菌株占80.43%,可分为含有traG和altA;含带sac-4t基因的traG和altA;只含有traG一部分保守序列的三种毒力岛类型.血清抗性实验表明9株sac-4阳性的淋球菌野生株均不具有血清抗性,而sac-4阴性的2号和11号菌株却产生了部分血清抗性和完全抗性.结论 不同毒力岛类型有着不同的毒力特点和基因型别,淋球菌血清抗性作用与毒力岛sac-4基因并无明显相关性.     

Promoter region methylation does not account for the frequent loss of expression of the Fas gene in colorectal carcinoma

Expression of the apoptosis-promoting Fas gene is frequently reduced or lost during the development of colorectal carcinoma. However, loss of heterozygosity at the Fas locus or Fas gene rearrangements do not account for the loss of expression of Fas, raising the possibility that methylation of the Fas promoter may inhibit gene expression in colorectal carcinomas. We have examined the Fas promoter region CpG island for evidence of hypermethylation in colorectal tumours. Forty-seven specimens of colorectal adenoma and carcinoma, as well as six samples of normal colonic mucosa, were examined by Southern blotting for methylation at HpaII and Cfol sites in this region. No methylation was detected in any of the specimens, suggesting that hypermethylation is not primarily responsible for the loss of expression of the Fas gene during colorectal tumorigenesis.     

颞浅动脉额支岛状头皮瓣眉再造

对３０例正常人颞浅动脉额支的走行进行测定，并应用颞浅动脉额支岛状皮瓣为１１例烧伤者再造眉１９侧，取得满意效果。选用额部发际处柔软毛发，再造眉较自然，不仅适用于男性，亦可为女性及儿童解除缺眉之苦。     

An objective assessment of the results of hypospadias surgery

OBJECTIVE: To compare the cosmetic result of tubularized incised-plate urethroplasty (Snodgrass method) with that of two established techniques, the meatal-based flap and onlay island flap repair. SUBJECTS AND METHODS: Photographs of the penis after hypospadias repair in 32 boys were assessed by a panel of five independent health professionals, including four surgeons with variable paediatric urological experience and a urology nurse. Twenty patients had a distal and 12 a proximal meatus. The Snodgrass technique was applied by one paediatric urologist for either distal (10) or proximal (six) hypospadias. A Mathieu repair was used for distal hypospadias (10) and an onlay preputial island flap for proximal hypospadias (six) by a second paediatric urologist. The panel was asked to grade cosmesis as poor, unsatisfactory, satisfactory or very good (points 1-4) for each of the following aspects of penile appearance: meatus, glans, shaft and overall appearance. Photographs were taken in a standard way, with a standard distance, lighting and two views, one of the dorsal surface and one ventral, for each patient. Signed written consent for the study was obtained from each family. RESULTS: The mean assessment score for any aspect of cosmesis was significantly higher for the Snodgrass technique (P < 0.05). The mean score (95% confidence interval) for the meatus was 0.76 (0.4-1.1) points higher for the patients with a Snodgrass repair than those with a Mathieu or onlay island flap repair (P = 0.002). Correspondingly, the values for the glans were 0.67 (0.38-0.97) (P = 0.003), shaft 0.42 (0.16-0.69) (P = 0.01) and overall appearance 0.62 (0.24-1.0) (P = 0.01) points higher for the Snodgrass repair. The Snodgrass technique was more effective in producing a vertically orientated meatus (87.5%) than the Mathieu and Duckett onlay repairs (37.5%; P = 0.009). CONCLUSION: The Snodgrass technique, as assessed by this panel, had a better cosmetic outcome than the Mathieu and Duckett onlay island flap repairs. The assessment of cosmesis in hypospadias surgery is potentially more objective when several health professionals, not involved in the surgery, compared the various methods of repair.     

Cluster of acute infantile spinal muscular atrophy (Werdnig-Hoffmann disease) in a limited area of Reunion Island

A retrospective study of Werdnig-Hoffmann disease (spinal muscular atrophy type 1) was undertaken on Reunion Island. Nineteen WH cases born between 1969 and 1980 were recorded belonging to thirteen sibships of the European population of the island.
Genealogical analysis, going back to the XVIIth century (1642), showed a relationship among the 13 families, which were derived from a common ancestral pair.
A founder effect is the most probable explanation for the concentration of Werdnig-Hoffmann disease in the area.     

A genomic population genetics analysis of the pathogenic enterocyte effacement island in Escherichia coli: the search for the unit of selection

Comparative genomic analysis is a powerful tool for understanding the history and organization of complete genomes. The mathematical tools of population genetics combined with genomic analysis provide a powerful approach to dissect heterogeneities in genome evolution. This study presents a hierarchical analysis of the enterocyte and effacement island (35 kb), which is found in the enteropathogenic and enterohemorrhagic strains in Escherichia coli and in Citrobacter rodentium. The locus of enterocyte and effacement in E. coli is considered to be a clonal unit inside a clonal organism and is expected to evolve as a single unit. This analysis examines the clonal assumption by determining genetic diversity, GC content, and the substitution rates at the different functional levels of (i) the complete pathogenic island, (ii) the five operons in which the island is organized, and (iii) for each of the individual 41 genes that comprise the locus. We find that there is a conserved region that is composed of genes that belong to the type III secretion system and that may be products of horizontal transfer. A more diverse region is composed of genes for secreted proteins and genes that we infer to be original components of the E. coli genome. This genetic mosaic seems to be differentially affected by selection and mutation. Our results suggest that recombination and selection may be breaking this structure so that different elements are, at best, weakly coupled in their evolution. These observations suggest that the units of selection are not the complete island, but rather, much smaller units that comprise the island.     

Labioscrotal island flap in feminizing genitoplasty

Background/Purpose

Stenosis of the vaginal introitus is the most frequent complication after genital reconstruction for ambiguous genitalia associated with congenital adrenal hyperplasia (CAH). With the aim of enlarging the vaginal introitus, the authors present a technical modification of the introitoplasty that uses a bilateral cutaneous island flap based on the perineal superficial branches of the internal pudendal artery.

Methods

Eleven girls with CAH and Prader III to V genital ambiguity were included. Feminizing genitoplasty was performed in 1 stage. Bilateral cutaneous labioescrotal island flaps, based on the posterior labial artery, were included in the introitoplasty. The cosmetic results of the genitoplasty were evaluated by photographic analysis of the external genitalia.

Results

Integrity of the vaginal introitus as well as excellent integration of the flap and absence of additional scars in the donor area were assessed in all girls.

Conclusions

This modified island flap is technically feasible and reproducible producing no additional sequels in the donor area. It uses perineal skin that is usually excised in other techniques avoiding the use of harvesting skin from adjacent areas. Thus, it can be a useful additional procedure in the introitoplasty in association with the currently used techniques.     

Mosaic genes and mosaic chromosomes-genomic variation in Streptococcus pneumoniae

The genome sequences of two strains of Streptococcus pneumoniae, one of the major human pathogens, are currently available: that of the nonencapsulated laboratory strain R6, the origin of which dates back to the early 20th century, and of the serotype 4 TIGR strain isolated recently. The two genomes are not only different in size (2 versus 2.16 Mb) but differ also by approximately 10% of their genes, many of which being organized in large clusters. Their strain-specific genes and gene clusters are described here. The R6 genome contains 69 kb organized in six large regions that are absent from the TIGR strain, which in turn contains an extra 157kb in twelve clusters compared to R6. In addition, the TIGR strain contains 13 clusters of 4 kb and larger that are not shared by a variety of genetically different S. pneumoniae strains. Many regions bear signs of gene transfer events such as the presence of insertion sequences, transposable elements, and putative site-specific integrases/recombinases. Three strain-specific regions are devoted to genes encoding proteins with the cell wall anchor motif LPXTG which are important for the interaction with host cells and appear to be highly variable, similar to cell wall-associated choline-binding proteins.