Search PubMed⌕ Search

Biomedical subjects

M Takimoto

Publications and source records attributed to M Takimoto.

At least 91 records · Page 5Linked to original sources

Distinct factors bind the AP-1 consensus sites in gibbon ape leukemia virus and simian virus 40 enhancers.

We have demonstrated that the gibbon ape leukemia virus (GALV) enhancer AP-1 element and the simian virus 40 AP-1 enhancer element bind different factors in HeLa nuclear extracts. A 39-kilodalton HeLa nuclear protein and the c-fos protein bind to the GALV element. Antibodies to c-fos abolish binding to the GALV AP-1 site. In contrast, anti-c-fos immunoglobulin fails to inhibit formation of the simian virus 40-specific complex from extracts of HeLa cells. Thus, AP-1-binding complexes are subject to compositional variation at different binding sites.

Animals↗

[Comparing development with physical fitness, motor ability, and health of children among various living environment].

This study had the purpose to compare with development of fitness, motor ability and health among various living environments of the sea-side, the urban, and the mountain districts, where were situated at Nadachi town on the suburbs of Niigata Prefecture. Five hundred thirty-five children (aged 4-15 yrs) were measured at the kindergarten, the fundamental school, and the junior high school. Measuring items of the physique were the height, the weight, the chest circumference, the sitting height, and the foot area. Physical fitness tests were the muscular grip-strength, the lung vital capacity, the closed-eye single-leg balance, the dipping time of the upper extremity, the vertical jump, the standing trunk flexibility, the endurance run, and pull-up. And, motor ability tests were the finger tapping, 5m shuttle run, 50m dash, and the ball throwing. As items of health inspection, the blood pressure (systolic and diasystolic) and the visual ability were adopted. As results of this study, following data were obtained; 1) At the sea-side environment, development of the muscle power, the respiratory function, and the physique were showed much faster rate of growth at the childhood than that of the other ones, significantly (P less than 0.01). 2) At the mountain environment, the arch-bend of the foot print only were appeared larger areas than that of the other ones, significantly (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

[A case report of compression of right pulmonary artery and bronchus by aneurysmal dilated ascending aorta in tetralogy of Fallot--suspension of ascending aorta].

The patient was a 63-days-old boy who was admitted to our hospital because of moderate cyanosis and tachypnea. After admission, severe respiratory distress and emphysematous change of the right lung on the chest X-ray developed progressively. Echocardiogram and angiocardiogram demonstrated that a tetralogy of Fallot associated with right aortic arch and absence of pulmonary valve, and revealed remarkably dilated ascending aorta which compressed the right pulmonary artery and bronchus. Therefore, the emergency operation in that the ascending aorta was suspended to the 2nd rib was performed through a right thoracotomy. After surgery, his respiratory distress and emphysema of the right lung completely disappeared. To our knowledge, this is the 2nd reported case in which suspension of ascending aorta was successfully performed for pulmonary complication in congenital cardiovascular anomalies as this patient.

Airway Obstruction↗

[Surgical experiences of Cor triatriatum in infancy].

Three operative cases with Cor triatriatum, age ranged from 30 days to 16 months, were presented. All types were IB1 of Lucas-Schmidt's classification and one patient was associated with right upper PAPVC. One patient died of low output syndrome due to preoperative shock. Communication of abnormal diaphragm in left atrium varied from small and multiple to 5 mm in diameter. Their preoperative diagnoses were established by two-dimensional echocardiogram prior to angiocardiogram and the intracardiac communications were well evaluated by color doppler echocardiogram which was superior to angiocardiogram in this evaluation. Postoperatively, no abnormal diaphragm were detected in two survivors. The diagnosis and operative procedure for this anomaly were discussed on.

Angiocardiography↗

Depression of T cell-mediated immunity and enhancement of autoantibody production by natural infection with microorganisms in spontaneously hypertensive rats (SHR).

We studied the effects of breeding conditions on the development of immunological abnormalities in spontaneously hypertensive rats (SHR) with congenital T cell depression. The depression of T cell functions, the production of natural thymocytotoxic autoantibody (NTA), and the development of polyarteritis nodosa were more evident in SHR reared under a conventional (CV) environment than in specific-pathogen-free (SPF) SHR bred in a semi-barrier system. Enhancement of these immunologic abnormalities was also observed by the conventionalization of SPF-SHR. A high frequency of antibodies to mouse hepatitis virus (MHV), Sendai virus, and Mycoplasma pulmonis was detected in CV rat sera, whereas no antibodies were detected in SPF-SHR. The experimental infection of Sendai virus induced the enhancement of T cell depression and of NTA production in SPF-SHR. We interpret these results to mean that the natural infection of microorganisms causes an acceleration of immunologic abnormalities in SHR reared in a CV environment.

Animals↗

[Clinical and pharmacokinetic studies of gentamicin in intravenous drip infusion to children].

Eighteen children with urinary tract infection were treated with intravenous drip infusion of gentamicin (GM), and clinical efficacy and pharmacokinetics were studied. Ages of the patients ranged from 2 months to 12 years. Doses of GM ranged 1.0 to 2.5 mg/kg every 8 to 12 hours, and treatment continued for 4 to 10 days. Among 18 patients treated, clinical results were excellent in 12, and good in 6. Values of BUN and creatinine remained within normal range in all patients during and after the GM treatment. One child had an eosinophilia. There were no cases that showed signs and symptoms of oto- and nephrotoxicity. Twenty eight time-serum level curves were studied in 16 patients during and after intravenous infusion of GM over 30 minutes. Doses were 1.0 mg/kg in 4, 1.9-2.0 mg/kg in 14, and 2.2-2.5 mg/kg in 10. Peak serum levels at 30 minutes after the start of infusion were 2.66-7.38 micrograms/ml (average 5.45 micrograms/ml) in cases receiving 1.0 mg/kg, 4.67-10.8 micrograms/ml (7.26 micrograms/ml) in 1.9-2.0 mg/kg, and 6.16-16.5 micrograms/ml (8.86 micrograms/ml) in 2.2-2.5 mg/kg. Elimination half-lives were 1.75-2.48 hours (average 2.10 hours) in cases with ages less than 1 year, 1.58-2.58 hours (2.01 hours) with 1 to 6 years, and 1.20-3.07 hours (1.66 hours) with 7 to 12 years who were given doses of 1.9-2.5 mg/kg. There were no significant differences in pharmacokinetic parameters between first and last administration in these patients, suggesting that no accumulation occurred with above mentioned doses. Urinary recovery of GM ranged from 21.9 to 99.2 percent (average 62.48%) within 6.5 hours after the initiation of drip infusion.

Child↗

Enhanced immunogenicity of the cultured rat fibrosarcoma KMT-17 by cultivation in a low concentration of fetal calf serum.

We examined in different culture conditions alterations in the tumorigenicity and immunogenicity of an A3 clone that had been derived from a rat fibrosarcoma KMT-17. When a fetal calf serum concentration in a culture medium was lowered from 10 to 1%, the tumorigenicity was diminished while the immunogenicity was enhanced in a reversible manner; this was accompanied by a reversible prolongation of the in vitro doubling time. These phenomena were not due to an increase in the quantities of the original tumor-associated antigen and/or of the rat major histocompatibility complex (RT1) but seemed to be due to the appearance of a unique antigen(s) that was detected by an antibody taken from rats immunized with A3 tumor cells cultured in the low fetal calf serum concentration; this antigen(s) may consist of glycoprotein and exist as a crypt antigen(s). These phenomena were measured by an absorption test and flow cytometric analysis. Our observations suggest that the in vitro culture condition of tumor cells, in particular their culturing in the low fetal calf serum concentration medium, modifies the surface of tumor cells and causes a diminishment in their tumorigenicity and an enhancement of their immunogenicity.

Animals↗

Assay of ptaquiloside, the carcinogenic principle of bracken, Pteridium aquilinum, by mutagenicity testing in Salmonella typhimurium.

The mutagenicity of ptaquiloside, the carcinogenic principle of Pteridium aquilinum, was tested in Salmonella typhimurium TA100 and TA98. Under weakly basic conditions (pH 8.5), ptaquiloside decomposed into a conjugated dienone (considered to be the ultimate form), which was mutagenic in both strains. A novel bioassay, using the pre-incubation method at pH 8.5 with S. typhimurium tester strains was developed for the assay of ptaquiloside extracted from plants. By this bioassay the ptaquiloside content of ferns collected at different localities during various seasons, and in various parts of the plant was determined. The ubiquitous presence of ptaquiloside in fresh plant materials was confirmed. Bracken processed in alkali was found not to contain the carcinogen.

Carcinogens↗

Sequences responsible for erythroid and lymphoid leukemia in the long terminal repeats of Friend-mink cell focus-forming and Moloney murine leukemia viruses.

Despite the high degree of homology (91%) between the nucleotide sequences of the Friend-mink cell focus-forming (MCF) and the Moloney murine leukemia virus (MuLV) genomic long terminal repeats (LTRs), the pathogenicities determined by the LTR sequences of the two viruses are quite different. Friend-MCF MuLV is an erythroid leukemia virus, and Moloney MuLV is a lymphoid leukemia virus. To map the LTR sequences responsible for the different disease specificities, we constructed nine viruses with LTRs recombinant between the Friend-MCF and Moloney MuLVs. Analysis of the leukemia induced with the recombinant viruses showed that a 195-base-pair nucleotide sequence, including a 75-base-pair nucleotide Moloney enhancer, is responsible for the tissue-specific leukemogenicity of Moloney MuLV. However, not only the enhancer but also its downstream sequences appear to be necessary. The Moloney virus enhancer and its downstream sequence exerted a dominant effect over that of the Friend-MCF virus, but the enhancer sequence alone did not. The results that three of the nine recombinant viruses induced both erythroid and lymphoid leukemias supported the hypothesis that multiple viral genetic determinants control both the ability to cause leukemia and the type of leukemia induced.

Animals↗

Inductions of ornithine decarboxylase and DNA synthesis in rat stomach mucosa by 1-nitrosoindole-3-acetonitrile.

Administration of 1-nitrosoindole-3-acetonitrile (NIAN) at doses of 40 to 300 mg/kg body weight by gastric intubation to male F344 rats induced up to 100-fold increase in ornithine decarboxylase activity with a maximum after 24 hr and up to 10-fold increase in DNA synthesis with a maximum after 16 hr in the pyloric mucosa of the stomach. These results suggest that NIAN has potential tumor-promoting activity in carcinogenesis in the glandular stomach.

Acetonitriles↗

[Pharmacokinetics of amikacin in infants and children].

Twenty-one children, from 41 hours to 12 years of age, were given amikacin (AMK) for suspected bacterial infections. In the 41 hours old newborn infant, the half-life of AMK was 6.9 hours. As infants' ages increase, half-lives of AMK became shorter. The trend toward a shorter half-life in an older child was the most marked during neonatal period. At an age of 7 days, the half-life was shorter than 3 hours. In infants exceeding 6 months of age, ages did not make differences in the length of half-lives. The apparent volume of distribution in newborn was, as average, 350.6 ml/kg body weight. The average for children 5 years and older was smaller, 280.7 ml/kg. The peak level-dose ratio was 2.8 (micrograms X ml-1 X mg-1 X kg) in newborns. There was a tendency that this ratio increased with age. The average ratio for children over 5 years was 4.5 (micrograms X ml-1 X mg-1 X kg). In summary, the 2 remarkable observations obtained from the present study were; 1) The trend that the half-life of AMK shortens as the child grows older was clearest in neonatal period. 2) Peak serum level produced by the same dose per kilogram body weight had a tendency to increase with ages of children.

Age Factors↗

Synergistic effects of the myc and ras oncogenes on ganglioside synthesis by BALB/c 3T3 fibroblasts.

The effects of oncogene activation on glycosphingolipid (GSL) synthesis by a mouse fibroblast clonal cell line were studied. A transfectant that expressed the activated ras gene showed a definite change in the composition of acidic GSLs, probably an increase in polysialoganglioside, while one that expressed the myc gene showed only a slight change. Neither transfectant grew in soft agar. However, another transfectant, which expressed both the myc and ras genes, and grew in soft agar, showed a more dramatic increase in the acidic GSL component. Thus, activations of the myc and ras oncogenes have a synergistic effect on GSL synthesis during transformation.

Animals↗

Demonstration of herpes simplex 1 virus antigen mouse brain after fixation.

The effects of several fixatives and fixation periods on recovery of viral antigen by indirect immunofluorescence (IF) and indirect immunoperoxidase (IP) were examined in mouse brains infected with type-1 herpes simplex virus. In 10% formalin, the sensitivity of antigen detection by IF decreased after one month fixation and viral antigen was barely detectable after fixation for three months. But in 10% buffered formalin antigenicity was not lost after six months. Similar effects were obtained by IP; however, specimens fixed in 10% formalin for three and six months showed positive reactions. Viral antigen was detectable without enzyme digestion in paraffin materials fixed in Bouin's, Carnoy's and Dubosq-Brazil solutions, but when treated with proteolytic enzyme for three hours, antigen could not be detected by either IF or IP. Ten per cent buffered formalin, Bouin's or Dubosq-Brazil solutions are recommended as fixatives for retrospective immunohistochemical and histopathological studies of viral infection in autopsy and biopsy materials.

Animals↗

[Clinical and pharmacokinetic evaluation of cefotiam in neonates and young infants].

Seven neonates and young infants were treated with cefotiam (CTM) in doses ranging from 8-25.6 mg/kg every 6 to 24 hours for 1 to 14 days, and the clinical efficacy and side effects were evaluated. Among 5 infants with bacterial infections including bacteremia, perianal abscess, pneumonia, urinary tract infection and probable sepsis and meningitis, clinical responses were excellent in 1 and good in 4 patients. In the 7 patients, no side effect attributable to CTM was observed. Serum concentrations of CTM were measured in 5 patients administered with 10 to 20 mg/kg of CTM by bolus intravenous injection. Peak serum concentrations of 21.9 to 38.0 micrograms/ml were noted in samples taken at 15 minutes after injection. Serum half-lives of the drug were 2.35 hours in 2 day-old neonate, 0.72 to 0.85 hours in 3 infants of 25 to 37 days, and 8.46 hours in an 18 day-old neonate with renal insufficiency.

Bacterial Infections↗