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Biomedical subjects

M Kamiya

Publications and source records attributed to M Kamiya.

At least 145 records · Page 8Linked to original sources
PubMed1990

Extraintestinal strobilar development of immature Echinococcus multilocularis in laboratory rodents following intratracheal inoculation of the protoscoleces.

Intratracheal inoculation of Echinococcus multilocularis protoscoleces was performed in prednisolone tertiary-butylacetate(PTBA)-treated and untreated golden hamsters and AKR/J mice. Repeated PTBA treatments prior to the day of inoculation prevented the influx of neutrophils against the cestode. More than 1 month after infection, living immature adult forms of E. multilocularis, showing some somatic prolongation, were recovered from the pulmonary alveolar space of PTBA-treated golden hamsters, in the absence of any cystic development.

Animals↗
PubMed1990

Malignant mesothelioma of the tunica vaginalis.

A case of a malignant mesothelioma of the tunica vaginalis is presented. The patient with an intrascrotal mass was a 32-year-old Japanese male who had no history of asbestos exposure. The tumor was located on the surface of the right testis and was composed of columnar to polygonal cells with glandular and papillary structures. It showed many mitoses and focal invasion of the tunica albuginea. The tumor cells contained alcian blue- and Hale's colloidal iron-positive, hyaluronidase-digestible materials. Immunohistochemical stains for cytokeratin and vimentin were positive, while those for carcinoembryonic antigen, epithelial membrane antigen, Leu-M1, and factor VIII-related antigen were negative. The systemic examinations revealed no other tumors. Based on these findings the tumor was diagnosed as malignant mesothelioma of the tunica vaginalis. The differential diagnosis is discussed under the histologic, histochemical, and immunohistochemical points of view and the previous literature is reviewed.

Adult↗
PubMed1990

Establishment, development and fecundity of Taenia crassiceps in the intestine of prednisolone-treated Mongolian gerbils and inbred mice.

Worm establishment, development and fecundity of Taenia crassiceps in the intestine of prednisolone (PTBA)-treated, 15- and 4-week-old Mongolian gerbils and 9-week-old inbred mice of 4 strains (AKR/J, BALB/cAn, B10D2/oSn and C57BL/KsJ) were investigated following oral administration of metacestodes. Gerbils were divided into 5 groups of 4 animals each according to the host age and commencement day of PTBA-treatment (day -13, -7 or 0 relative to infection). Worm recovery from the intestine on day 35 postinfection was not affected by host age, but fewer worms were recovered the earlier the commencement of PTBA-treatment. Worm size, determined by wet weight, total length and proglottis number, correlated inversely with worm burden, suggesting they were affected by the crowding effect. Proglottides were released normally in the faeces but were markedly depressed in all groups except for that of young gerbils. Furthermore, egg production and its development in gravid proglottides were markedly depressed in all groups. In PTBA-treated mice of 4 strains, sexually mature but not gravid worms were recovered from all mice of the AKR/J strain on days 20-32 postinfection, but none or few worms from the intestine of the others. PTBA-treatment did not inhibit all protective host defence mechanism(s) in the unnatural or alternative rodent definitive host of T. crassiceps.

Animals↗
PubMed1990

Survival, strobilation and sexual maturation of Echinococcus multilocularis in the small intestine of golden hamsters.

Echinococcus multilocularis survived, strobilated and matured sexually in the small intestine of 6-week-old male golden hamsters that were either non-treated or treated with prednisolone tertiary-butylacetate (PTBA), following oral administration of 20 000 protoscoleces. Non-treated hamsters harboured the adult worms for up to 25 days post-infection (p.i.). Hamsters treated with PTBA from the day of infection (day 0 p.i.) harboured more adults than the non-treated, and their survival periods were extended. Moreover, a remarkable improvement in worm recovery, development and survival periods was observed in hamsters additionally treated with PTBA on days -- 14 and -- 12 p.i., and the worm development including proglottisation, sexual maturation and egg formation was comparable with that in dogs. With the present results it is suggested that Echinococcus/rodent systems represented by the E. multilocularis/golden hamsters may rejuvenate the current stagnant research on host-parasite interactions of the definitive host-stage and egg-stage of Echinococcus.

Animals↗
PubMed1990

Complete life cycle of the canid tapeworm, Echinococcus multilocularis, in laboratory rodents.

Mongolian gerbils, Meriones unguiculatus, when treated at intervals of 2-6 days with prednisolone tertiary butyl acetate, sustained infection with adult Echinococcus multilocularis in the small intestine, with the tapeworm exhibiting normal strobilation and egg production as in the natural canid host. Host age is critical for the survival of the tapeworm in normal gerbils; parasites survive for only 2 days in 20-wk-old animals, 4 days in 4-wk-old animals, but at least 7 days in 3-wk-old animals. The host age dependence in parasite recovery between days 28-37 postinfection was not affected by treatment from around the day of infection. Starting the treatment before infection (on day -17 relative to infection) remarkably improved the tapeworm's survival within the intestine of older animals. Eggs produced in this rodent model system 28 days postinfection were infective to rodents such as Mongolian gerbils and gray red-backed voles, Clethrionomys rufocanus bedfordiae, by oral or intraperitoneal inoculation. The E. multilocularis/Mongolian gerbil system can replace the natural canid hosts as a new way to obtain infective eggs and to analyze host-parasite interactions. The development of an alternative definitive host for zoonotic tapeworms may accelerate experimentation in this field.

Aging↗
PubMed1990

Glutaric aciduria type II: autopsy study of a case with electron-transferring flavoprotein dehydrogenase deficiency.

An autopsy study of glutaric aciduria type II in a 62-day-old Japanese boy is presented. The diagnosis was made by analysis of organic acids in the urine. Immunoblot analysis of liver homogenate confirmed the diagnosis, revealing absence of electron-transferring flavoprotein dehydrogenase. The major findings were fatty changes of variable degree in many organs and tissues, the most severe being found in cardiac myocytes, hepatocytes, renal tubular epithelium, and skeletal muscle fibers. Other pertinent findings included multicystic and dysplastic kidney, pulmonary alveolar proteinosis, and spongiosis and gliosis of the spinal cord. The thymus was markedly depleted, and lymphocytes in the lymph nodes were mainly B cells. Although some of these changes may have been secondary to the sepsis and immunosuppression complicating 2 months of intensive care, the abnormal organic acid metabolism with severe acidosis may have been a significant contributing factor.

Acidosis↗
PubMed1990

Parasites from the Asiatic black bear (Ursus thibetanus) on Kyushu Island, Japan.

Two Dirofilaria ursi, six Trichodectes pinguis and numerous Haemaphysalis megaspinosa were obtained from an Asiatic black bear (Ursus thibetanus) shot in Kyushu, Japan. The presence of two parasites specific to black bears may indicate the existence of a wild population, although the bears are regarded to be extinct on Kyushu Island.

Animals↗
PubMed1990

Echinococcosis in Kenya: transmission characteristics, incidence and control measures.

Kenya has the highest reported incidence of human hydatid disease in the world. Up to about 30% of cattle, 15% of goats and 13% of sheep harbour the infection. The causative agent of the disease in Kenya is Echinococcus granulosus and a complex strain picture of this parasite has been postulated to occur. The domestic dog is the main definitive host of E. granulosus in Kenya but infection in wild carnivores has also been reported. Hydatid cysts have also been found in wild herbivores. Although the domestic cycle has been shown to be the most important mode of transmission of the disease, a sylvatic cycle is also known to exist. The etiology of hydatid disease, the strain differentiation of E. granulosus found in Kenya, and the role that wildlife plays in the transmission cycle is reviewed. The current trends in the incidence of hydatid disease in man and livestock, and the efforts being made to control the disease are also discussed.

Animals↗
PubMed1990

Development and sexual maturation of Taenia crassiceps (Cestoda) in the golden hamster.

The development of cysticerci of Taenia crassiceps to mature tapeworms in the intestinal tract of cortisone-treated and untreated golden hamsters is described. The development of the worms in untreated hamsters is as follows. Maturation and branching of the uterus and the presence of ova in the uterus were observed on day 15 postinfection (PI). By day 21 PI, fertilization had taken place, as evidenced by the presence of sperm in the seminal receptacle. On day 28 PI, shelled eggs were observed in feces. The rate of development of the worms in cortisone-treated hamsters was similar to that observed in untreated hamsters. More worm recovery and a longer period of worm survival were seen in the cortisone-treated than in the untreated hamsters. Thus, both cortisone-treated and untreated golden hamsters can produce normal gravid individuals of T. crassiceps.

Animals↗
PubMed1989

Pathological studies of aberrant peripheral nerve bundles of spinal cords.

Aberrant peripheral nerve fiber bundles, i.e., masses of peripheral nerve fibers without perineural sheath cells, are found in the perivascular spaces of some spinal cords. The 514 spinal cords examined for these structures were separated into two groups; 507 spinal cords without definite necrotic lesions (group 1) and 7 spinal cords (group 2) with old necrotic lesions in which there were numerous aberrant peripheral never bundles (APNB). In group 1, APNB were found in 41.0% of spinal cords. The incidence was the same for both sexes and increased in proportion to age. APNB were found predominantly in the middle and lower thoracic segments. On the transverse sections, APNB were located mainly in the central gray matter and in the anterior median fissure. Ultrastructural and histochemical studies showed that the myelin in APNB was peripheral in origin. Serial sections showed continuity between APNB and nerve roots. In group 2 cases, APNB were diffusely distributed throughout the old necrotic lesions and not restricted to perivascular areas.

Adult↗
PubMed1989

Laboratory rearing of the Amami rabbits (Pentalagus furnessi Stone, 1900) in captivity.

Five Amami rabbits in each sex were firstly introduced into the Central Institute for Experimental Animals. The authors intended to breed the Amami rabbits in the laboratory. During breeding, the Amami rabbits were nervous to external stimuli, easily frightened and always showed escaped behaviour. They were given pelleted foods for rabbits and pikas and also given apples and sweet potatoes as additional foods. The Amami rabbits were showed to practice coprophagy in the same way as laboratory rabbits. After introduction, they required 13 months to reach the maximum body weights which were 2.73 kg for females and 2.71 kg for males. Matings were attempted with one female and one male in newly deviced reproductive cages. By seventy-four matings, one pregnancy was produced and one child was delivered. This neonate (2 day old) had closed eyes and ears, incisors and brown short hair and weighed 100 g. Unfortunately, the pup died on the 4th day. The body length of this stage was 15 cm.

Animal Husbandry↗
PubMed1989

Gastrointestinal helminth fauna of Japanese moles, Mogera spp.

One trematode, Echinostoma macrorchis, 2 cestodes, Hymenolepis diminuta and Choanotaenia spasskii and 5 nematodes, Parastrongyloides winchesi, Tricholinstowia talpae, Heterakis spumosa, Trichuris sp. and Capillaria soricis were obtained from 129 Mogera wogura, 233 M. kobeae and 28 M. tokudae, which were collected from almost all over Japan. All present cases were new host and locality records. The discovery of T. talpae in Japan shows the wide distribution of this species from Japan to Europe.

Animals↗