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Biomedical subjects

A Ono

Publications and source records attributed to A Ono.

At least 127 records · Page 7Linked to original sources
PubMed1995

Conformational aberrance of the sendai virus F0 protein in thapsigargin-treated cells allowing exit from the endoplasmic reticulum but causing arrest at the Golgi complex.

Thapsigargin and ionomycin inhibited the intracellular transport of the Sendai virus F0 protein. Depletion of Ca2+ from intracellular Ca2+ store(s) is critical for the inhibition, since ionomycin was more effective in the absence of extracellular Ca2+ than in its presence. Transport of F0 was arrested between the trans-Golgi complex and the plasma membrane [Ono, A. and Kawakita, M. (1994) J. Biochem. 116, 649-656], but only when thapsigargin was added before the synthesis of F0. This implies that F0 was committed to later arrest in the endoplasmic reticulum. Non-reducing SDS-polyacrylamide gel electrophoresis revealed a conformational abnormality of F0 immediately after pulse-labeling in thapsigargin-treated cells. The abnormality did not affect the exit of F0 from the endoplasmic reticulum, but paralleled its later arrest at the trans-Golgi stage. Pulse-labeled and 1-h-chased F0 was endoglycosidase H-resistant even in thapsigargin-treated cells, but was not recognized by mAb f-49, a monoclonal antibody that recognizes the corresponding F0 intermediate in uninhibited cells. The misfolded F0 may escape from recognition by means of the quality control system of the endoplasmic reticulum, but another system in the Golgi complex may complement the former. The arrested F0 was rapidly degraded.

3T3 Cells↗
PubMed1995

Cry j I, a major allergen of Japanese cedar pollen, has pectate lyase enzyme activity.

In the course of analyzing the partial amino acid sequences of Cry j I, a major allergen of Japanese cedar (Cryptomeria japonica) pollen, we found a peptide fragment which has a significant homology to some pectate lyase isozymes secreted by plant pathogenic bacteria. Therefore, we investigated whether Cry j I has pectate lyase activity. Cry j I reacted with polygalacturonic acid, resulting in the release of unsaturated uronide products. The optimum temperature and pH for the reaction were 60-70 degrees C and pH 10. The enzymatic reaction had an absolute Ca2+ ion requirement. These characteristics were very compatible with the character of the pectate lyase isozymes reported previously. These results clearly show that Cry j I has pectate lyase activity.

Allergens↗
PubMed1995

[Drug sensitivity and expression of beta-lactamase in enterococci isolated at Okayama University Hospital].

The following results were obtained from a study of Enterococci isolated at the Okayama University Hospital from 1990 to 1994. 1) The isolation frequency of Enterococci was about 6% for each year. 2) The percentage of Enterococcus faecalis (E. faecalis) among Enterococci decreased each year, but the percentage of Enterococcus faecium (E. faecium), and Enterococcus avium (E. avium) increased each year. 3) Results of drug sensitivity tests revealed that the incidence of ofloxacin (OFLX) resistant E. faecalis and E. avium increased each year. Also, the resistance of E. faecalis to ampicillin (ABPC), the primary medication choice for treating E. faecalis, increased each year. 4) A few vancomycin (VCM) non-sensitive Enterococci were isolated. These bacteria showed low-sensitivity toward ABPC, imipenem (IPM), gentamicin (GM), and OFLX, and the extent of multiple drug resistance increased each year. 5) One hundred strains of Enterococci were selected to examine the expression of beta-lactamase using the broth method and the iodine-starch method. However, beta-lactamase producing strains were not detected.

Anti-Bacterial Agents↗
PubMed1995

Increased number of circulating HTLV-1 infected cells in peripheral blood mononuclear cells of HTLV-1 uveitis patients: a quantitative polymerase chain reaction study.

AIMS: This study aimed to characterise the status of viral infection in patients with HTLV-1 uveitis (HU) by quantifying the circulating HTLV-1 infected cells in the peripheral blood. METHODS: Genomic DNA samples of peripheral blood mononuclear cells (PBMC) were obtained from 25 patients with HU, 14 patients with tropical spastic paraparesis/HTLV-1 associated myelopathy (TSP/HAM), and 21 asymptomatic carriers of HTLV-1. Quantitative polymerase chain reaction (PCR) of the gag region of HTLV-1 provirus DNA was performed on these DNA samples. To confirm the PCR, genomic Southern blot hybridisation was performed to identify integrated HTLV-1 provirus. This procedure detected a few percent of HTLV-1 infected cells in the PBMC. RESULTS: Most of the HU patients had a significantly increased number of circulating HTLV-1 infected cells (mean (SD) 3.84% (4.45%) of the PBMC), whereas the percentage of infected cells in most asymptomatic carriers was less than 1% (0.54% (1.11%)). Most of the TSP/HAM patients also had a relatively high percentage (11.63% (7.67%)). The differences among these three groups were highly significant by the Mann-Whitney U test. CONCLUSION: The results suggested that the increase in the number of HTLV-1 infected cells is one base for the development of inflammatory HU lesions, as it is for TSP/HAM.

Adult↗
PubMed1995

Urinary trehalase activity is a useful marker of renal proximal tubular damage in newborn infants.

To clarify the reliability of urinary trehalase activity as a marker of cellular proliferation and/or damage of renal proximal tubules, the activity was examined in healthy newborn infants or infants treated with tobramycin, a drug known as causing tubular cell damage. Eighty-one newborn infants (56 mature infants and 25 premature infants) were enrolled in the study. Urinary trehalase was examined using a spot urine sample during the first 7 days of age and on the 10th day of age. A good positive correlation was observed between urinary trehalase activity/creatinine ratio (T/Cr) on the 10th day of age and conceptional age or body weight (n = 46, r = 0.58, p < 0.001). Urinary trehalase of 29 healthy mature infants was higher during the first few days of age, after which it decreased to an almost steady level. Urinary trehalase of 6 premature infants during the first few days of age was significantly lower than that of mature infants, after which it increased and became equal to that of the mature infants on the 7th day of age. Treatment with ampicillin (100 mg/kg) and tobramycin (5 mg/kg) of 6 mature infants with pneumonia for 6 days resulted in a significant elevation of the urinary T/Cr. The extent of this elevation was greater than that of the urinary N-acetyl-beta-D-glucosaminidase (NAG) activity/creatinine ratio (NAG/Cr). A significant correlation was observed between the urinary T/Cr and the urinary NAG/Cr (r = 0.67, p < 0.01) or gamma-glutamyl transpeptidase/creatinine ratio (r = 0.48, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1995

Glucose infusion paradoxically accelerates degradation of adenine nucleotide in working muscle of patients with glycogen storage disease type VII.

We investigated the effect of glucose infusion on adenosine triphosphate degradation in skeletal muscle of patients with glycogen storage disease type VII. Three patients and six healthy subjects exercised on a bicycle ergometer twice, once with 20% glucose infusion and once with saline infusion. The glucose infusion increased plasma glucose levels to 170 to 182 mg/dl and serum insulin levels to 30 to 50 microU/ml, while it markedly decreased plasma free fatty acid levels. The exercise-induced increases in plasma ammonia, inosine, and hypoxanthine were much larger with glucose than with saline infusion in the patients. Urinary excretion of inosine and hypoxanthine with glucose infusion was twice as high as that with saline infusion. No such differences were present between glucose and saline infusion in the healthy subjects. Glucose infusion therefore accelerates the energy crisis in working muscle of patients with glycogen storage disease type VII, probably due to a decrease in fatty acid utilization.

Adenine Nucleotides↗
PubMed1995

Study on hepatic artery chemoembolization using temperature-sensitive liposome or lipiodol emulsion.

As a novel method for the medical application of liposomes, we have tried hepatic artery chemoembolization using temperature-sensitive liposomes with hyperthermia for the treatment of hepatic tumors. In this study, the effect of temperature-sensitive liposomes was compared with that of Lipiodol emulsion, which has been used clinically. The temperature-sensitive liposomes, consisting of dipalmitoylphosphatidylcholine or Lipiodol emulsions entrapping doxorubicin, were administered into the hepatic artery of hepatic tumor-bearing rats via a cannula. Doxorubicin administered in a liposomal form showed a high accumulative property toward tumors, with heating, while that in the emulsion form showed a slow release property toward tumors. Not only was tumor growth inhibited, but also, an actual diminishing of the tumor was observed in each form. Side effects were also examined: an abnormal rise in GPT, or necrosis of the normal tissues in liver, which was often observed in hepatic artery chemoembolization using Lipiodol emulsion, was remarkably reduced in the liposomal chemoembolization.

Animals↗
PubMed1995

Reproductive and developmental toxicity studies of toluene. I. Teratogenicity study of inhalation exposure in pregnant rats.

Toluene is a widely used solvent in industry which is the subject of abuse among the younger generation. A teratogenicity study of toluene by inhalation exposure was carried out in Sprague-Dawley rats and the effects on dams, fetuses and offspring were assessed. Pregnant females were exposed to 600 or 2000 ppm toluene for 6 h/day from day 7 to day 17 of pregnancy. The control group inhaled conditioned clean air under the same exposure conditions. Maternal exposure to 2000 ppm toluene caused significant toxic effects such as body weight suppression of dams and offspring, high fetal mortality and embryonic growth retardation, but no external, internal or skeletal anomalies were observed in the fetuses of any treated group. In addition, there were no differences in the results of pre- and postweaning behavioral tests of the offspring. However, no toxic or teratogenic changes which could be related to toluene exposure were apparent in the 600 ppm group. Further studies are warranted with toluene at higher concentrations applied during the period of organogenesis.

Abnormalities, Drug-Induced↗
PubMed1995

Toxicity study of europium chloride in rats.

EuCl3.6H2O was administered by gavage for 28 consecutive days to groups of 10 male and 10 female rats (Slc:Wistar strain) at doses of 0, 40, 200, or 1000 mg/kg/day. Additional groups of male and female rats receiving the 0 and 1000 mg/kg doses were used to assess recovery after 14 days subsequent to cessation of compound administration. Body weights and food consumption were measured, and hematological, clinical biochemistry, and histopathological examination were performed. The concentrations of europium (Eu) and of essential elements in organs were determined by ICP-MS or ICP-AES. In the rats of each sex dosed at 200 and 1000 mg/kg, the body weight gain significantly decreased because of reduction in food consumption. Hyperkeratosis of the forestomach and eosinocyte infiltration of the stomach submucosa were found in both sexes receiving the 1000 mg/kg dose group, suggesting an irritation effect by EuCl3.6H2O. The Eu levels increased dose dependently in the liver, kidneys, spleen, and femurs, and the accumulated volume of Eu in these organs was estimated to be about 1/100,000 of the total dosed amount. The administration of EuCl3.6H2O increased the serum iron concentration in males and the serum total iron binding capacity in each sex and decreased cholinesterase activity in females in the 1000 mg/kg dosed group. Iron concentrations in the spleen and strontium concentrations in the femurs of rats of both sexes dosed at 1000 mg/kg were significantly decreased. We concluded that the no-observed-effect level is 200 mg/kg/day. Our investigation demonstrated that elemental analyses of organs is a useful approach to toxicological study.

Animals↗
PubMed1995

Human B lymphocytes respond to Epstein-Barr virus with an increase in intracellular Ca2+ concentration.

Early events in the infection of human B lymphocytes by Epstein-Barr virus (EBV) were examined by measuring calcium ion concentration from fluorescence with fura-2. Intracellular Ca ion concentration ([Ca2+]i) of B lymphocytes increased in response to EBV application. Three types of [Ca2+]i-increase were observed: (1) an early transient [Ca2+]i-increase; and (3) a slow [Ca2+]i-increase without the early transient [Ca2+]i-increase. The early transient increase was observed in the zero Ca2+ condition, but it was suppressed when cells were pretreated with ryanodine before exposure to the virus. The slow sustained [Ca2+]i increase was not observed in Ca(2+)-free extracellular conditions. These results suggest that the early transient [Ca2+]i increase is mediated by Ca2+ release from intracellular Ca storage sites, and the slow sustained [Ca2+]i increase is mediated by the Ca2+ influx through the plasma membrane. Virus receptors on the surface of B lymphocytes were stained with a fluorescence marker, rhodamine, and the capping process after EBV application was observed under a confocal microscope. The capping process and the localization of virus receptors were observed after EBV application. The time course of the capping process seems similar to that of the slow, sustained [Ca2+]i increase.

Adult↗
PubMed1995

[The anesthetic management of a patient with Fabry's disease].

There are no reports of anesthesia for a patient with Fabry's Disease in Japan. Fabry's Disease is a rare hereditary disease that is characterized by alpha-galactosidase deficiency caused by deposition of glycolipid in many organs. The disease may be complicated by cardiac ischemic disease, neurological disorder and renal failure. The patient is a 45-year-old female with cholelithiasis who underwent cholecystectomy. This patient had been hospitalized repeatedly for the past 15 years because of the chronic pyelits, and hyperglycemia, and nephrosis. She developed chronic renal failure, hemodialysis was started when diagnosis of Fabry's Disease was made at age of 41. Preoperative electrocardiogram revealed ischemic change on leads II, V5 and V6. Nifedipine was administered for hypertension. The anesthesia was induced with thiopental followed by vecuronium for endotracheal intubation, and maintained with nitrous oxide, oxygen and isoflurane. Accompanied by nicardipine for hypertension, and vecuronium for muscle relaxation using a neurotransmission monitor (Relaxograph), nitroglycerin was continuously infused. We avoided the effect of atropine for reversal of muscle relaxation because most of the patients were complicated with hypohidrosis. During administration of nitroglycerin and nicardipine, the neuromuscular blocking effects of vecuronium could be prolonged. The neuromuscular monitoring was useful in this case.

Anesthesia↗