Demonstration of the transmissible agent in tissue from a pregnant woman with Creutzfeldt-Jakob disease.
Explore the source record for details and available documents.
Biomedical subjects
Publications and source records attributed to Y Ishihara.
Explore the source record for details and available documents.
A high-performance liquid chromatographic method with electrochemical detection is described for quantification of pamaquine, primaquine and carboxy primaquine in calf plasma. After the proteins had been precipitated with acetonitrile, the drugs were separated on a 5-microns C18-modified polymer gel column with an isocratic mobile phase. The detection limit was 0.01 microgram/ml in plasma for all three compounds. The applicability of the method in pharmacokinetic studies was demonstrated by determining the plasma concentrations of the three substances in calves administered a single dose of pamaquine or primaquine.
Explore the source record for details and available documents.
We studied, for two years, the prevalence of indigenous human enteric viruses in wild oysters gathered each month from the bottom of Mikawa Bay, Aichi Prefecture, Japan. Viruses were detected periodically in 9 out of 54 oyster pools prepared by the acid or polyethylene glycol precipitation method although all these 9 pools met current national bacteriological safety standards. Since most of the serotypes of the enteric viruses detected in the oysters were identical with those of viruses isolated from sick children living in the area, it is suggested that contamination of enteric viruses in the oysters would depend on the prevalence of enteric viral infections in the local inhabitants.
We investigated adenovirus (Ad) infection of the intestine and Ad group-specific fecal IgA antibody responses in seven infants who were followed up from birth to 16 months to seven years of age. We isolated in tissue culture from fecal samples not only enteric Ad type 41 but also other Ads (types 2, 3, 5, 6, and 12). We also detected Ad antigens in the feces by ELISA at the times of infection with even non-enteric Ads, suggesting that a large amount of antigens were produced in the intestine. We found that repeated Ad infections with different serotypes were occurring and there were good fecal IgA antibody responses at each time. The infection seemed usually mild or asymptomatic: only one out of 23 occasions of the detected infections required hospitalization.
A female child with mosaic partial deletion of 11q is reported. At 1 month of age she was presented with cogenital glaucoma, trigonocephaly and multiple minor anomalies. She exhibited growth retardation and the typical phenotype of 11q- syndrome. G-banding analysis failed to show any abnormality, although subsequent high resolution banding revealed the abnormal karyotype 46,XX,del(11)(q23.3 q24.2)/46,XX,del(11)(q23.3 q25). This case is a second case of mosaic 11q- syndrome and her karyotype suggests that the region of 11q23.3-11q24.2 is critical in 11q-syndrome. Congenital glaucoma has never been reported as a complication of 11q- syndrome.
We studied the transmission of hepatitis A virus (HAV) in 45 families, which members were diagnosed as hepatitis A in 8 hospitals in 1990. Feces and sera from 50 patients and their 126 family members were tested for HAV-specific antigen and IgM antibody by ELISA or polymerase chain reaction (PCR) technology. From the interval of the onset of hepatitis or detection of HAV antigen in feces, HAV transmission was recognized in 11 (24.4%) of 45 families. The transmission was found to be concerned with contacts of the children and that from children to parents was found in 4 families and the reverse in 2. HAV antigen was detected from feces of 4 family members before onset of icterus by ELISA and furthermore, 3 by PCR. It was indicated that these methods would be used to prevent the transmission in a family, day-care centers, or institutions for the mentally retarded.
We studied the detection of the HA gene of human influenza viruses in throat swabs obtained from the outbreaks of influenza in school children utilizing the polymerase chain reaction (PCR) method. Sensitivity and specificity of the PCR method was compared to conventional virus isolation using MDCK cells. Three pairs of primers for PCR in detecting the HA genes of AH1, AH3, and B influenza viruses showed both subtype and type specificity. The dilution experiments showed that influenza viruses, as few as 1.1-3.5 plaque-forming units per 50 microliters, were sufficient for the detection of HA genes by PCR method and the detection rate by PCR method was 2-3 fold higher than that by conventional method. Our results showed that the PCR method was a fast, sensitive and reliable method for the diagnosis of influenza infections.
We have shown that infusion of zymosan-activated plasma (ZAP) in sheep causes acute lung injury and downregulates peripheral blood neutrophils in that elicited superoxide release is reduced for at least 24 h after the infusion. The present study was designed to test the following hypotheses: 1) peripheral blood neutrophils are representative of neutrophils marginated in the pulmonary circulation, 2) blood neutrophils are downregulated because neutrophils developing in bone marrow are similarly affected, and 3) downregulated neutrophils have a reduced capacity to produce tissue injury. In a series of experiments in 21 sheep, we showed that elicited superoxide release was similar in peripheral blood neutrophils and in marginated neutrophils washed out of the pulmonary vascular bed. Measurements of superoxide release from blood and bone marrow neutrophils collected 2-24 h after ZAP infusion revealed progressive downregulation with time and greater downregulation of superoxide release in bone marrow neutrophils compared with peripheral blood neutrophils. Finally, after downregulating peripheral blood neutrophils, subsequent infusion of ZAP in conscious sheep produced sequestration of neutrophils in the pulmonary circulation but failed to produce a sustained increase in lung lymph protein clearance. The results suggest that neutrophil downregulation, as measured in vitro, is expressed in vivo as reduced ability of neutrophils to produce tissue injury when challenged by an activating agent.
The effect of alpha 1-proteinase inhibitor (alpha 1Pi) administration on the acute lung injury and subsequent fibrosis induced by bleomycin (BLM) was examined in hamsters. Pulmonary lesions were quantitatively reduced in alpha 1Pi-administered BLM-treated (BLM-alpha 1Pi) animals compared with animals treated by BLM alone (BLM-control) at both 7 days (acute stage) and 30 days (fibrotic stage) after BLM treatment. Analysis of intraalveolar cells from bronchoalveolar lavage (BAL) fluid revealed that neutrophils and lymphocytes were significantly decreased in the BLM-alpha 1Pi animals at 7 days after BLM treatment and that 30 days after BLM treatment macrophages as well as neutrophils and lymphocytes were remarkably decreased in the BLM-alpha 1Pi animals. The elastase activity in supernatants of BAL fluid during 7 days following BLM treatment was detected, but there was no difference between the two groups. In vitro studies on neutrophil responsiveness to stimulation of BAL fluid at 3 days after BLM treatment revealed noticeable chemotaxis and generation of superoxide anion of isolated neutrophils, but alpha 1Pi did not show any inhibitory effects on neutrophil responsiveness. We suggest that alpha 1Pi administration ameliorates pulmonary fibrosis preceded by acute lung injury induced by BLM treatment in hamsters and that the inhibitory effects of alpha 1Pi on lung injury may not be brought about by altered elastase activity, chemotaxis, or superoxide generation in neutrophils. Alternative mechanisms are discussed.
A series of 2-alkoxy-2,8-diazaspiro[4.5]decane-1,3-diones and related compounds were synthesized and tested for muscarinic receptor binding affinity using [3H]pirenzepine and [3H]oxotremorine M as ligands. They were also evaluated for agonistic activities in the guinea pig ileum assay. 2-Methoxy- 2,8-diazaspiro[4.5]decane-1,3-dione (1i) was found to be a relatively M1 selective agonist. It reversed CO2-induced impairment of passive avoidance response with long duration of action, but also displayed peripheral effects at low doses. To minimize these side effects, we proposed the idea of conjugation of 1i with a muscarinic antagonist. The carbamate linked conjugate (1u) of 1i with methylatropine was therefore examined.
The Incidence of mushroom poisoning was surveyed statistically from 1959 to 1988 in Japan. The results are summarized as follows: 1. During the past three decades, the total number of incidents of mushroom poisoning was 2,096, which involved 10,924 patients and 72 deaths. The average number of incidents was 70 cases per year, involving 364 patients and 2.4 deaths, and the number of incidents decreased gradually every year. Mushroom poisoning usually happened most frequently in September and October. 2. Considering regional differences, the incidence of mushroom poisoning was more frequent in the northeastern part of Japan than in the southwestern part. The incidences of mushroom poisoning in the prefectures of Nagano, Hokkaido, Niigata, Iwate and Fukushima were relatively high. 3. Three species of mushrooms, L. japonicus, R. rhodopolius (R. sinuatus) and T. ustale caused the majority of all poisonings. 4. The rates of total patients and fatalities for each type of poisoning, which were classified according to the symptoms caused, were 90.3% and 10.7% in the type with cholera-like symptoms, 90.2% and 0.2% in that with gastro-intestinal irritation, and 74.1% and 0% in that with neurological symptoms, respectively.
Neutrophils which are isolated in the lung adhere to endothelial cells due to chemotactic factors, and release various proteases, superoxide anions and prostanoids in inflammatory processes. However, this host defense mechanism can cause tissue damage. Excessive adherent neutrophils are not always derived from lung injury. We have previously reported that an increase in cell density in human neutrophils attenuates superoxide anion generation by cell to cell communication (autoregulation). Autoregulation of the protein kinase c stimulator, phorbol myristate acetate, and also of the cell membrane receptor stimulator, N-formyl-methionyl-leucyl-phenyl-alanine was observed. The autoregulation was not related to the presence of extracellular Ca2+ not to a change of [Ca2+]i induced by stimulants. These results suggest that neutrophils accumulated in the lung tissue have a built-in defense mechanism induced by membrane to membrane contact of neutrophils, which protects tissues from an excessive inflammatory response.
In the present study, the number of leukocytes was increased in smokers, dependent on the amount of exposure to smoke (duration and cigarette number/day). The differential leukocyte count did not differ between smokers and non-smokers. Leucocyte-associated serum components such as alpha 1-antitrypsin, alpha 2 globulin, and complements did not differ in smokers. There was no relationship between neutrophils in peripheral blood and BAL fluid. These findings suggest that an increased number of leukocytes in smokers is not attributable to activation of complement, and that anti-proteinase serum levels including alpha 1-antitrypsin and alpha 2 globulin are unchanged in both smokers and ex-smokers.
Postoperative changes in peripheral venous functions were determined by Ga-In strain gauge plethysmography in 28 surgical patients, and central venous functions and urine catecholamine levels were also measured. The results were as follows: 1. The maximum venous outflow (MVO) and arterial blood inflow volume (AF) of the healthy arms tended to increase with age, but showed no sex or right-to-left difference. 2. MVO, AF and venous distensibility were decreased postoperatively, and the decreases were greater in the patients with major surgery than in those with minor surgery. 3. MVO in the patients with high urine levels of adrenaline and noradrenaline showed a greater decrease than those in normal subjects, and the majority of these patients were found to have had major surgery. There was a negative correlation between the urine noradrenaline level and MVO. 4. The decrease in peripheral venous functions preceded the decrease in central venous functions. 5. The postoperative decrease in peripheral venous functions was considered to be the result of active vasoconstriction due to hypersecretion of catecholamines caused by surgical stress and increase in the extravascular pressure. 6. Measurement of venous functions of the arm may be a good parameter for detecting circulatory disturbances due to surgical stress.
The relation between alcohol and nonfatal acute myocardial infarction (AMI) was examined in a case-control study of 89 male patients and 271 control subjects in Fukuoka, Japan. Patients admitted for the first AMI at 2 hospitals in Fukuoka City were aged 40 to 69 years, and control subjects were recruited based on the telephone directory of the city. Information on alcohol drinking and potential coronary risk factors was obtained by using a self-administered questionnaire, and past drinkers were separated from lifelong abstainers in the analysis. After adjustment for age, occupation, cigarette smoking, strenuous exercise, body mass index, hypertension, diabetes mellitus and parental heart disease, the risk of AMI was progressively less with increasing levels of alcohol consumption. With those who never drank as a referent, adjusted odds ratios for current drinkers consuming less than 30, 30 to 59, and greater than or equal to 60 ml/day of alcohol were 1.11 (95% confidence interval 0.51 to 2.42), 0.31 (0.11 to 0.83), and 0.13 (0.05 to 0.36), respectively. These findings add to the body of data showing that alcohol drinkers are less likely to have AMI.
In March 1989 a large outbreak of acute gastroenteritis occurred simultaneously among schoolchildren and teachers at nine elementary schools in Toyota City, Japan. Illness was observed in 3236 (41.5%) of 7801 schoolchildren and 117 (39.4%) of 297 teachers. The main clinical symptoms were diarrhoea, vomiting, nausea and abdominal pain. Gastroenteritis was significantly associated with the consumption of school lunch served by one particular lunch preparation centre. One food handler at the centre suffered from gastroenteritis during the outbreak. Small round structured virus (SRSV) was detected in 4 of 8 stool specimens from sick persons. The school lunch contaminated by the infected food handler is the most probable source of this outbreak due to SRSV.
Fecal extracts from 12 subjects in outbreaks of oyster-associated nonbacterial gastroenteritis were inoculated with BS-C-1 cells for isolation of the causative viruses. Cytopathic agents were isolated from 3 patients. No cross-neutralizing reactions were observed between the isolates and prototypes of human enteroviruses. The isolates were approximately 30 nm in diameter and had a distinct ultrastructure resembling that of astroviruses. Four polypeptide bands with molecular sizes of 42, 28, 27, and 22 kDa were seen on SDS-PAGE analyses. Seroconversion against the isolate was observed in 18 (31.6%) of 57 patients involved in five of seven outbreaks examined by neutralization test. A protein band characteristically reactive with the paired serum samples was detectable at 42 kDa by immunoblot assay. These results suggested that some small round viruses resembling astroviruses might show cytopathic effect in BS-C-1 cells and may be associated with an oyster-related gastroenteritis.