Japanese journal of medical science & biology最新文献

A new renicolid cercaria, Cercaria kuwaitae X sp. n., from the prosobranch gastropod Cerithium scabridum from Kuwait Bay is described. The new cercaria is nonstyleted gymnocephalous with voluminous Y-shaped excretory vesicle, flame cell formula 2[(3 + 3 + 3) + (3 + 3 + 3)] = 36, and without caudal fins. Surface topography of the new cercaria is studied by scanning electron microscopy. Domed papillae are abundant on the anterior and lateral aspects of the body, ciliated papillae are sparse dorsally. The ventral sucker bears nine domed papillae. Domed papillae form two circles around the oral sucker with three circles of spines in between. This is the first renicolid cercaria to be recorded in a gastropod from the Arabian Gulf region.

Ciprofloxacin was evaluated along with other commonly used antibiotics against a total of 425 clinical isolates obtained from urine samples. Samples were collected from outdoor patients from different parts of Dhaka city. Susceptibility tests were done by the standardized disk diffusion method. Among the tested drugs, the percent susceptible rates observed were: ciprofloxacin (74%), ampicillin (29%), cephalexin (54%) and trimethoprim-sulfamethoxazole (43%) tested against all organisms; gentamicin (73%) tested against gram-negative organisms and erythromycin (72%) tested against gram-positive organisms. Ciprofloxacin showed better activity against gram-negative isolates (80%) compared to the other antibiotics. However, strains highly resistant to ciprofloxacin were detected among commonly isolated gram-negative urinary pathogens: Escherichia coli (18%), Klebsiella species (19%) and Pseudomonas species (30%). Overall susceptibility rate for gram-positive cocci was significantly low for all the antibiotics tested including ciprofloxacin (62%). Minimal inhibitory concentration (MIC) of ciprofloxacin was measured for all resistant and susceptible urinary tract infection (UTI) isolates. This study indicates emerging ciprofloxacin resistance among most UTI bacterial pathogens. Increasing resistance against ciprofloxacin demands coordinated monitoring of its activity, and rationale use of the antibiotic in UTI.

Studies carried out on entomological and rodent surveillance in agroclimatic and feral biotopes of five districts of Maharashtra and two districts of Gujarat revealed that the terrain features of the seven districts surveyed were conducive to wild rodent species, Tatera indica, a natural reservoir of plague and vector flea species, Xenopsylla cheopis. A total of 214 Tatera indica and three Bandicoota bengalensis were collected from burrows by the digging method and 89 rat fleas were retrieved. The flea index calculated ranged from 0.26 to 1.0 in different districts. The examination of blood serum samples, contact tissue impression smears and tissue organs (heart, lung, liver and spleen) of these wild rodents did not reveal any evidence of plague activity. The natural harbourages of Tatera indica were found to be elevated land or raised margins of agricultural fields or barren land with thorny bushes/xerophytic plants and parthenium grass. Agricultural fields having wet soil were found to be the preferred harbourages of Bandicoota bengalensis. Movement of wild rodents toward human settlement was observed to be the common phenomenon during the harvesting season which may lead to the creation of favorable conditions for plague outbreaks.

A total of 205 Vibrio cholerae O1 isolates from recent cholera epidemic in Senegal were analyzed by conventional methods, polymerase chain reaction (PCR) for genes encoding cholera toxin (ctx A), zonula occludens toxin (zot) and accessory cholera enterotoxin (ace), ribotyping and toxinogenotyping. Ribotyping after Bg1 I digestion of total DNA revealed that ribotype B5a, the predominant ribotype of the seventh pandemic in Africa and Asia, was not isolated. A new ribotype designated B27 in our database is predominant and was associated with a new toxinogenotype designated TB31.

The relationship between the level of endotoxin released from Pseudomonas aeruginosa by exposure to beta-lactam antibiotics and the lethal activity against D-galactosamine (D-GalN)-sensitized mice was examined. In vitro treatment of P. aeruginosa with imipenem (IPM) exclusively caused low-level release of free endotoxin, which was not lethal for D-GalN-sensitized mice. Treatment with other beta-lactam antibiotics, such as ceftazidime (CAZ), meropenem (MEPM) and cefozopran (CZOP) caused high-level release of free endotoxin and it exhibited the lethal action against D-GalN-sensitized mice. This study demonstrated close association of free endotoxin released by antibiotic treatment with the lethal activity.

There are warnings of the contamination of cell cultures with HeLa cells in many laboratories in the world. The cell lines JTC-3, OG and OE that were established in Okayama in 1959, 1969 and 1971, respectively, were examined for human papillomavirus (HPV) 18 DNA by Southern blot hybridization. The HPV 18 DNA detected in these three cell lines showed hybridization patterns characteristic of the HPV 18 DNA in the HeLa cell line established in 1951. Southern hybridization patterns of HPV 18 DNA in the cellular DNA of the C4-II cervical cancer cell line that was established in the USA in 1962 was different from that of HeLa cells. These results suggest that the JTC-3, OG and OE cell lines have been contaminated by HeLa cells.

Superficial eye infections by herpes simplex virus (HSV) constitute a major cause of corneal disease, necessitating the need for corneal transplantation in many patients. Eighty-three corneas from 46 post-mortem donors received from the David Lucas Eye Bank in Manchester were analyzed by Vero cell culture and the polymerase chain reaction (PCR) technique to detect HSV. There was no evidence of a characteristic cytopathic effect in any of the cultures. A 350-bp PCR product corresponding to the HSV thymidine kinase (TK) was detected by southern blotting in only 2.4% (2/83) of samples. In contrast, approximately 70% of samples yielded a 758-bp PCR product. Although this low prevalence of HSV in corneas may be encouraging, it is high for the actual transplantation program if the viral DNAs maintain their abilities to replicate.

Hepatitis C virus (HCV) core and envelope proteins are suggested to be responsible for the pathogenesis of hepatic and extrahepatic manifestations in chronic hepatitis C. Moreover, the core protein is implicated in the regulation of the transcription of cellular genes including c-myc, RB and p53. Determining the subcellular localization of the core and envelope proteins is therefore necessary to elucidate their behaviors, particularly in vivo ones, regarding the interaction with transcriptional regulatory proteins or gene elements. We defined the subcellular localization of HCV envelope and core proteins which were expressed in substantial levels in the liver of transgenic mice. Subcellular fractionation by ultra-centrifugation revealed that the envelope proteins were present principally in the microsomes of the liver, while a small amount of the protein was detected also in the nuclei. Immunohistochemistry confirmed the localization of envelope proteins in the nuclei. In contrast, the core protein was detected principally in the cytoplasmic fraction, where it was closely associated with lipids. A low level of the core protein was detected also in the nuclei and microsomal fraction. These results suggest possible interaction of the HCV structural proteins with some factors in hepatocytes thereby perturbing intracellular circumstances.

Age-specific prevalence of anti-hepatitis A virus antibody (anti-HAV) was surveyed with 2,708 sera collected in 1994 in various areas of Japan. By age-group analyses, we found strong association of anti-HAV antibody with higher age group. The prevalence ratios of antibody in the groups of 30-34, 35-39, 40-44, 45-49, 50-54, 55-59, 60-64 and 65 years or older were 0, 4.2, 22.0, 44.8, 57.6, 76.4, 84.5 and 91.4%, respectively. Geometric mean titers of anti-HAV antibody in the positive age groups were approximately 6,000 mIU/ml. The seropositives among older population were ascribed to the infections more than 40 years ago and the high anti-HAV titers have been maintained since that time. In Japan, people younger than 40 years of age are extremely risky to HAV infection, since 99% have no antibody. Those in forties are also risky since two-thirds of them are seronegative. In Japan, an inactivated vaccine was licensed in 1994. Vaccination may be recommended for such high-risk groups as travelers going to endemic areas, patients who have received blood product medication and child-care staffs.