Effects of vancomycin and ofloxacin on rabbit ERG in vivo

The retinal toxicity of vancomycin and ofloxacin was studied by electroretinogram (ERG) before and after intravitreal injection in rabbits. Vancomycin is known to be effective on methicillin-resistant Staphylococcus aureus. A dose of 1mg vancomycin caused no ERG change for at least eight weeks after injection. The feature that ERG became non-recordable during one to four weeks after an intravitreal injection of 10mg vancomycin, with recovery of only the c-wave was conspicuous. A dose of 200 micrograms ofloxacin did not cause deterioration of the b-wave, the c-wave or the oscillatory potentials throughout the follow-up period up to eight weeks. Judging from the susceptibility of each ERG component to antimicrobials and taking into account the difference of vitreous volume between rabbits and humans, clinical doses of intravitreal single-shot injection should be less than 1mg for vancomycin and 200 micrograms for ofloxacin.     

Effect of cystathionine beta-synthase variant 844ins68bp and methylenetetrahydrofolate reductase A1298C polymorphisms in xenografts on 5-FU efficacy and doubling time

The association of MTHFR and CBS variants with the doubling time and responsiveness to several chemodrugs was analyzed in 26 human cancer xenografts. The tumors homozygous for the absence of insertion (NN) for the CBS 844ins68bp were more chemosensitive than those with insertion (NI) to TS-1 (P=0.0048), suggesting a potential effect of this variant on fluoropyrimidine efficacy. Furthermore, the doubling time of tumors with a variant C allele (AC or CC) in MTHFR-A1298C was significantly longer than that of tumors with a normal allele (AA) (P=0.0008). Twenty-nine cellular proliferation-related genes were associated with MTHFR-A1298C genotyping and with the doubling time.     

A CASE OF EARLY GASTRIC CANCER ACCOMPANIED BY DIEULAFOY ULCER IN A YOUNG WOMAN

A case of early gastric carcinoma accompanied by Dieulafoy ulcer is presented. The patient, a 26‐year‐old female, visited our emergency room with chief complaints of massive hematemesis and tarry stool. The initial endoscopic examination revealed a superficial depressed lesion with a faded color accompanied by a tiny ulcer with converging folds at the anterior wall of the middle gastric body. Although no active bleeding vessel was found at that time, the patient was admitted to our hospital for further check‐ups and treatment. On the 6th hospital day, she developed massive hematemesis resulting in shock. Urgent endoscopy, this time, disclosed an exposed bleeding vessel at the small ulcer floor previously mentioned, and endoscopic hemostasis was achieved. Since, however, a biopsy at initial examination from the surrounding depressed area proved carcinoma, a partial distal gastrectomy was subsequently carried out. Histological examination of the resected specimen confirmed the diagnosis of carcinoma limited to the mucosa and submucosa along with findings consistent with Dieulafoy ulcer. This is a rare case of combination of early cancer and Dieulafoy ulcer particularly in such a young patient. A review of the literature is also presented.     

PEUTZ‐JEGHERS SYNDROME ASSOCIATED WITH RENAL AND GASTRIC CANCER THAT DEMONSTRATED AN STK11 MISSENSE MUTATION

A 75‐year‐old male was admitted to the gastroenterology unit of Nagoya City University Hospital due to epigastralgia after surgical treatment for right renal cancer. Endoscopy revealed advanced type 1 gastric cancer in the corpus of the stomach and multiple polypoid lesions in the stomach and duodenum. X‐ray examination of the small intestine using barium showed multiple polyps in the upper jejunum. Faint pigmentation on the palm was also detected. Peutz‐Jeghers syndrome (PJS) was diagnosed, despite a lack of family history. Total gastrectomy, resection of part of the upper jejunum and intraoperative endoscopic polypectomy of duodenal polyps was performed. This is the second reported case of PJS associated with renal cancer. We also detected a missense mutation in the tumor suppressor gene STK11 that, when mutated, is causative for PJS.     

Analysis of DNA copy number aberrations in hepatitis C virus-associated hepatocellular carcinomas by conventional CGH and array CGH.

To clarify the genetic aberrations involved in the development and progression of hepatitis C virus-associated hepatocellular carcinoma (HCV-HCC), we investigated DNA copy number aberrations (DCNAs) in 19 surgically resected HCCs by conventional CGH and array CGH. Conventional CGH revealed that increases of DNA copy number were frequent at 1q (79% of the cases), 8q (37%), 6p (32%), and 10p (32%) and that decreases were frequent at 17p (79%), 16q (58%), 4q (53%), 13q (42%), 10q (37%), 1p (32%), and 8p (32%). In general, genes that showed DCNAs by array CGH were usually located in chromosomal regions with DCNAs detected by conventional CGH analysis. Increases in copy numbers of the LAMC2, TGFB2, and AKT3 genes (located on 1q) and decreases in copy numbers of FGR/SRC2 and CYLD (located on 1p and 16q, respectively) were observed in more than 30% of tumors, including small, well-differentiated carcinomas. These findings suggest that these genes are associated with the development of HCV-HCC. Increases of MOS, MYC, EXT1, and PTK2 (located on 8q) were detected exclusively in moderately and poorly differentiated tumors, suggesting that these alterations contribute to tumor progression. In conclusion, chromosomal and array CGH technologies allow identification of genes involved in the development and progression of HCV-HCC.