The Kitasato archives of experimental medicine最新文献

The changes in the activity and the localization of alkaline phosphatase (ALP), gamma-glutamyl transpeptidase (gamma-GTP) and alpha-fetoprotein (AFP) were examined during cell regeneration in the galactosamine-injured rat liver. D-galactosamine was injected i.p. into rats at a single dose level of 400 mg/kg. The biochemical activities of ALP and gamma-GTP in rat liver homogenate increased significantly in comparison with those in the control rats 3 days and 4 days after administration of D-galactosamine. In the histochemical analysis, 3 days, 4 days and 5 days after the administration of the amino sugar, a high level of activity of both ALP and gamma-GTP was seen along the cell borders between adjacent hepatocytes. AFP was detected by the enzyme-labeled antibody technique in the cytoplasm of a few small hepatocytes around Glisson's sheath and epithelial cells of small tubules within Glisson's sheath which show morphological features similar to bile duct 3 days, 4 days and 5 days after the administration of the amino sugar. AFP was detected in serum by the western blotting method 3 days and 4 days after the administration of D-galactosamine, whereas serum albumin decreased significantly in the same period. In this study, it was shown that ALP, gamma-GTP and AFP were proper markers to justify the degree of the differentiation of hepatocytes during the state of proliferation.

Five strains of Staphylococcus hyicus subsp. hyicus were isolated: three strains (P-1, P-2 and P-3) from the crust on the body surface of 6-month-old pigs on a farm in Aomori prefecture, and two (P-5 and P-6) from both the crust on the body surface and the joint of a 1-month-old piglet with exudative epidermitis (EE) on another farm. The characterization of the isolates and the experimental infection of the piglets with strain P-1 were carried out. Subcutaneous inoculation with the bacterial suspension (10(10) CFU) produced EE to all nine piglets. Eight of them had exudation and exfoliation within 24 hr of infection. Histopathologically, disappearance of stratum corneum and necrosis with vacuolar degeneration of prickle cells were remarkable in the epidermis. Infiltration of neutrophils and lymphocytes were observed in the dermis. The results clearly indicate that S. hyicus is responsible for incrustation of the body surface of weanling pigs and exudative epidermitis in young piglets.

Drug resistance plasmids were detected in two drug resistant strains of Actinobacillus (Haemophilus) pleuropneumoniae serotype 2 isolated in Japan. One strain, Hpn25, was resistant to ampicillin, kanamycin, streptomycin and sulfonamides, and harbored two plasmids with a molecular size of 3.7 and 4.1 kilobases (kb). The other strain, Hpn18, which was resistant to streptomycin, tetracycline, and chloramphenicol, harbored three plasmids with a molecular size of 2.2, 12, and 35 kb. The resistance of Hpn 25 to streptomycin and sulfonamides is mediated by a 4.1 kb plasmid and that of Hpn 18 to streptomycin and chloramphenicol by one or more of the 2.2, 12, and 35 kb plasmids.

Splenic T lymphocytes from two strains of mice, BALB/c and B10.BR, infected with an attenuated strain of Salmonella enteritidis were cloned by the double-layer soft agar technique in the presence of interleukin 2 (IL 2), formalin-killed S. enteritidis (FKS) and syngeneic feeder cells. One Salmonella-reactive T cell line was established from each strain of mice. Both T cell lines bore Thy-1+, Lyt-1+ and L3T4+ surface markers as demonstrated by cytofluorography. Biological properties of the T cell lines were studied with respect to their ability to proliferate and produce lymphokines such as IL 2 and gamma-interferon (IFN-gamma) in response to Salmonella antigens, and to transfer adoptively protection against infection and delayed-type hypersensitivity (DTH). As the result of the present study, the T cell lines were proliferated specifically against several Salmonella and other bacteria, which belong to species of Enterobacteriaceae. Their proliferation required the presence of the specific antigen(s) and the compatibility in the I-A region of the H-2 complex between the T cell lines and feeder cells. The T cell lines could be proliferated with resultant production of IL 2 and IFN-gamma by in vitro culture in the presence of syngeneic feeder cells and Salmonella antigens. The protective activity assessed by the number of recoverable bacteria in spleens and livers after challenge with virulent S. enteritidis and DTH reactions to Salmonella antigen were exhibited by the T cell lines when transferred adoptively to naive syngeneic mice. These results suggested that different biological functions of cell-mediated immunity to Salmonella could be mediated by a single phenotype of T cell population.

In many experiments beginning in 1977 Prof. O. Prokop and Prof. W. Köhler discovered that the human haptoglobins are able to agglutinate group G-streptococci, but the reaction depends on the haptoglobin type. Haptoglobins of the types Hp 2-2 and Hp 2-1 are complete agglutinins and haptoglobin of the Hp 1-1 type is incomplete ("blocking") antibody. Later it was found that streptococci with the T4--antigen (from Lancefield types A, C and G) are suitable for the test.

In order to study the difference of uptake and distribution between hexavalent (Cr6+) and trivalent (Cr3+) chromium in isolated rat hepatocytes, the cells were incubated with Cr6+ or Cr3+ (1 mM Cr) at 37 degrees C for up to 60 min. Leakage of lactate dehydrogenase from the hepatocytes into the suspension medium as an indicator of cellular injury was facilitated by Cr6+ (K2Cr2O7) at 60 min of incubation, whereas Cr3+ [Cr(NO3)3] had no effect. After 60 min of incubation with Cr6+, about 33% of the added Cr was found in the hepatocytes, whereas incubation with Cr3+ resulted in transfer of about 66% of the added Cr to the cells. After 20 and 40 min of incubation with Cr6+, about 39% of cellular Cr was found in the cytosolic fraction of hepatocytes, followed by a reduction to about 35% after 60 min of incubation. However, Cr detected in the cytosolic fraction of hepatocytes incubated with Cr3+ was about 1% of cellular Cr. Cr-binding substances in the cytosolic fraction of hepatocytes incubated with Cr6+ were eluted with two Cr peaks by Sephadex G-200 chromatography. These Cr-binding substances in the low-molecular-weight fractions were separable into at least two substances by thin-layer chromatography. These results suggest that Cr6+ readily passes through the cell membrane and combines with substances already present in the cytosolic fraction of hepatocytes, unlike metallothionein induced by cadmium, followed by detoxification. Consequently, cellular injury might be induced by Cr6+ which could not combine with LMCr in the cytosolic space of the hepatocytes.

Staphylococcus aureus strains isolated from the 391 confirmed cases of staphylococcal food poisonings in Tokyo, in the period 1967-1986, were studied for their coagulase types. Consequently, it was found that all the isolates could be classified into the coagulase types II, III, VI and VII. Namely, the isolates from 54 (13.8%) of 391 outbreaks were typed as type II, 72 (18.4%) as type III, 38 (9.7%) as type VI, and 227 (58.1%) as type VII, respectively. Throughout the investigation, it was found that the outbreaks of staphylococcal food poisonings due to coagulase type VII organisms were remarkably increased since 1975.

More than 150 years ago the foundations were laid for the so-called HERBST effect which was subsequently forgotten. In the sixties the phenomenon was rediscovered by VOLKHEIMER at the Charité Hospital in Berlin and then reviewed through many experiments and publications. What is meant by the HERBST effect? If an experimental animal or even human being is given a larger amount of maize starch or also biscuits or some other products containing starch, starch bodies can be detected rapidly in venous blood already after minutes or half an hour later and in the urine after one hour and later. The term "persorption" has been coined for this interesting phenomenon. It is indeed surprising that it has met with so little attention. As a matter of fact, it constitutes the basis for our understanding of peroral immunization and of allergies. In the same way, feeding of carbon particles results in their appearance and detection in blood, kidney and urine. The same result is obtained by the intake of diatoms and what is even more important with meat fibres. I hope you are aware of the implications. When Professor NAGAI stayed in Berlin, we tried to receive the phenomenon. Since only a few cell nuclei are necessary for "genetic fingerprinting" we thought that after intake of 200 or 400 g of raw meat the type of food eaten could be determined from the urinary sediment by means of the fingerprint method which would be of forensic significance. Therefore, we eat meat and raw liver and examined the urinary sediment.(ABSTRACT TRUNCATED AT 250 WORDS)