Clinicopathologic significance of GLUT1 expression and its correlation with Apaf-1 in colorectal adenocarcinomas.

AIM: To investigate the role of glucose transporter 1 (GLUT1) expression in colorectal carcinogenesis and evaluate the correlation with clinicopathological parameters and apoptosis-activating factor-1 (Apaf-1) expression in colorectal adenocarcinomas. METHODS: We used tissue microarrays consisting of 26 normal mucosa, 50 adenomas, 515 adenocarcinomas, and 127 metastatic lesions. Medical records were reviewed and clinicopathological analysis was performed. RESULTS: GLUT1 expression was absent in normal mucosa and low or moderately apparent in 19 cases (38.0%) of 50 adenomas. However, GLUT1 expression was detected in 423 (82.1%) of 515 adenocarcinomas and in 96 (75.6%) of 127 metastatic lesions. GLUT1 expression was significantly correlated with female gender (P = 0.009), non-mucinous tumor type (P = 0.045), poorer differentiation (P = 0.001), lymph node metastasis (P < 0.001), higher AJCC and Dukes stage (P < 0.001 and P < 0.001, respectively). There was a significant inverse correlation between GLUT1 expression and Apaf-1 expression (P = 0.001). In univariate survival analysis, patients with GLUT1 expression demonstrated poor overall survival and disease-free survival (P = 0.047 and P = 0.021, respectively, log-rank test). CONCLUSION: GLUT1 expression was frequently increased in adenocarcinomas and metastatic lesions. GLUT1 expression was significantly correlated with poorer clinicopathologic phenotypes and survival of patients with colorectal adenocarcinomas.

Identification of an atypical integron carrying an IS26-disrupted aadA1 gene cassette in Acinetobacter baumannii.

An unusual class 1 integron was identified that carries an IS26-disrupted aadA1 gene cassette (designated as 'integron-IS26') in an imipenem-resistant Acinetobacter baumannii (IRAB) outbreak strain. DNA sequencing revealed that integron-IS26 contained two gene cassettes, the aac(6')-Im cassette and a peculiar aadA1 cassette that was disrupted by IS26 (disrupted aadA1 cassette). Southern blotting localised integron-IS26 to the chromosome. Nested polymerase chain reaction (PCR) was performed to define the frequency of integron-IS26 in five groups of bacteria. Nested PCR identified integron-IS26 in 19 (73.1%) of 26 clinical outbreak strains of IRAB, 10 (100%) of 10 IRAB isolated from environmental cultures, 3 (13.0%) of 23 imipenem-susceptible A. baumannii (ISAB) non-outbreak strains, 1 (3.6%) of 28 netilmicin- and tobramycin-resistant A. baumannii and none of the netilmicin- and tobramycin-resistant Pseudomonas aeruginosa. In conclusion, we have identified a novel class I integron that carries the aac(6')-Im cassette and an IS26-disrupted copy of aadA1 (integron-IS26) in most IRAB outbreak strains and in a few ISAB non-outbreak control strains. Integron-IS26 is located chromosomally.

[Comparison of clinical characteristics of patients with rotavirus gastroenteritis relative to the infecting rotavirus g-p genotype.].

BACKGROUND: Group A rotavirus is a major cause of severe diarrhea in children throughout the world. For the proper management of rotavirus infections, it will be helpful to know their clinical characteristics according to the G and P genotypes of the infecting virus. METHODS: The diarrheal stool specimens from patients hospitalized in Chosun University Hospital during 2002-2003 were tested for rotavirus by Dipstick 'Eiken' Rota kit. Rotavirus antigen-positive stool specimens were analyzed for group A rotavirus by RT-PCR, and the group A-positive PCR products were genotyped for P and G types by PCR. RESULTS: Among the 119 specimens analyzed for genotypes, the predominant strain was genotype G4P[6] (51.3%), followed by G2P[4] (19.3%), G1P[8] (7.6%), G3P[8] (5.0%), and G9P[8] (4.2%). To examine the characteristics of each rotavirus genotype, a clinico-epidemiological study was performed for 100 patients whose medical records were available. The frequencies of diarrhea, vomiting, dehydration, and fever; the rates of nosocomial infection and transfer from other hospitals; and the mean severity scores were significantly different among the patients infected with different types of rotavirus. Especially, patients with G4P[6] type were more likely than those infected with other genotypes to show the following distinct features: Most patients showed milder symptoms and were neonates transferred from other obstetric hospitals and 68.4% of the cases were nosocomial infection. G4P[6] strains were isolated almost all along the year. The mean severity scores of patients infected by G4P[6], G2P[4], G1P[8], G3P[8], and G9P[8] strains were 6.8, 9.5, 8.0, 9.0, and 10.8, respectively. CONCLUSIONS: Many features of rotavirus infections including the epidemic period, rate of nosocomial infection, age and severity of symptoms were different according to the genotypes of the infecting virus.

PFGE-based epidemiological study of an outbreak of Candida tropicalis candiduria: the importance of medical waste as a reservoir of nosocomial infection.

Between November 2002 and March 2003, an outbreak of candiduria occurred in the surgical intensive care unit (SICU) of a university-affiliated hospital in South Korea. This outbreak affected 34 patients and was caused by Candida tropicalis. To determine the source of the epidemic and the risk factors, surveillance cultures from the SICU, genotyping of Candida isolates by pulsed-field gel electrophoresis (PFGE), and a case-control study were performed. The surveillance cultures revealed that 6 environmental samples related to the urine disposal route were positive for C. tropicalis. The PFGE analysis of genomic DNA demonstrated identical band patterns for all of the C. tropicalis isolates obtained from SICU patients and the 6 environmental samples during the outbreak period, while epidemiologically unrelated strains showed unique PFGE band patterns. Although no risk factors were identified by the case-control study, this epidemiological investigation involving the use of molecular techniques suggests that improper disposal of infectious medical waste led to the cross-transmission of a single clone that was responsible for the outbreak of C. tropicalis candiduria in this SICU. After implementing a better urine disposal system and thorough hand washing procedures, no further clusters of candiduria were detected in the SICU.