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Biomedical subjects

T Katayama

Publications and source records attributed to T Katayama.

At least 181 records · Page 10Linked to original sources
PubMed1995

Effect of dietary sodium phytate on the hepatic and serum levels of lipids and on the hepatic activities of NADPH-generating enzymes in rats fed on sucrose.

The effect was investigated of dietary 0.5% sodium phytate on the hepatic and serum lipid status in rats fed on sucrose for 29 or 30 days. The increase in hepatic weight, levels of hepatic total lipids, triglyceride, cholesterol, serum triglyceride and phospholipid, and the activities of hepatic NADPH-generating enzymes due to sucrose feeding were generally depressed by dietary sodium phytate.

Animals↗
PubMed1995

Transcriptional regulation of tyrosine phenol-lyase gene of Erwinia herbicola AJ2985.

Induction and repression of tyrosine phenol-lyase (TPL; EC 4.1.99.2) of Erwinia herbicola AJ2985 were examined on the transcriptional level and it was shown that transcription of tpl was increased by the addition of tyrosine and decreased by the addition of glucose in the medium. The 5' flanking region of its gene, tpl, was analyzed and its transcriptional start point was determined. A presumed -35, -10 promoter region, TyrR box, and operator-like region were also found in this region.

Amino Acid Sequence↗
PubMed1995

The fine structure of dexamethasone-induced growth hormone cells in the anterior pituitary gland of the rat fetus.

The effect of synthetic glucocorticoid, dexamethasone (DEX), on the fine structure of the fetal growth hormone (GH) cell was examined in rats on Days 17-19 of gestation by the protein A-gold method of immuno-electron microscopy. GH cells appeared on Day 19 in the control fetuses. The DEX-induced GH cells of Day 17 fetuses displayed more immature features than those of Day 18, which closely resembled GH cells found in the control fetus on Day 19. Cytological changes which indicate increased secretory activity such as the development of the rough endoplasmic reticulum or enlargement of the Golgi complex, and an accumulation of secretory granules were evident only in the DEX-treated fetuses on Day 19. It is concluded that DEX not only accelerates the development of GH cells, as observed on Day 17 or 18, but also brings them to a functionally stimulated state by Day 19.

Animals↗
PubMed1995

Thrombotic thrombocytopenic purpura and myoglobinuric acute renal failure following radiation therapy in a patient with polymyositis and cervical cancer.

A 73-year-old woman was admitted to receive radiation treatment for uterine cervical cancer, however a complex series of events ensued, leading to death. She developed an acute exacerbation of polymyositis complicated by thrombotic thrombocytopenic purpura, rhabdomyolysis and acute renal failure. Radiation therapy may have produced an immune disturbance leading to the acute exacerbation of polymyositis. Auto-immune-mediated endothelial damage might have triggered a series of events leading to thrombotic thrombocytopenic purpura. Rhabdomyolysis seemed to be the main cause of acute renal failure.

Acute Kidney Injury↗
PubMed1995

[Spontaneous subcapsular hemorrhage: a rare clinical presentation of renal cell carcinoma].

We present a case of renal subcapsular hemorrhage caused by a small renal cell carcinoma. The patient was a 52-year-old housewife, presenting abdominal pain and vomiting, of abrupt onset. Modern imaging modalities clearly visualized a perirenal or subcapsular hematoma in her left kidney, but no underlying pathology, was found even on the arteriogram. Relying on the statistics based on more than 100 reported cases with the spontaneous renal rupture, nephrectomy was carried out. The renal carcinoma was of granular cell type (G2), and classified as pT2, pN0 and pM0. Difficulties in making a correct diagnosis as to the pathology and therefore a rational decision for nephrectomy were also stressed.

Carcinoma, Renal Cell↗
PubMed1995

[Autoimmune hemolytic anemia reactivated by alpha-interferon therapy in a case of chronic active C-type hepatitis].

A case with autoimmune hemolytic anemia (AIHA) induced by interferon-alpha (IFN-alpha) is presented. A 40-year-old male who had a previous history of autoimmune hemolytic anemia, agranulocytosis and thrombocytopenia was admitted to our hospital because of chronic C type hepatitis. Liver biopsy was performed, which diagnosed chronic active hepatitis and IFN-alpha was administrated at a dose of 3 Meg unit per day. 11 days after the initiation of the therapy he developed hemolytic anemia, but Coombs tests were negative. Although IFN was withdrawn 15 days later, anemia became progressively more serious. 20 days later, both direct and indirect Coombs tests became positive. He was diagnosed as AIHA and treated with methylprednisolone pulse therapy, then he recovered soon afterward. Further analysis of Coombs tests revealed that he had both cold type and warm type (IgG) autoantibodies which was the same type of antibodies for AIHA he suffered 10 years ago. In conclusion, latent AIHA may be reactivated by the treatment with IFN-alpha.

Adult↗
PubMed1995

[The present situation, treatment and prognosis of drug-resistant pulmonary tuberculosis. Cooperative Study Unit of Chemotherapy of Tuberculosis of the National Sanitoria in Japan].

We studied 266 patients with drug-resistant pulmonary tuberculosis at national sanatoria in Japan. The patients included 218 men (mean age, 58 years) and 48 women (mean age, 62 years). The levels of isoniazid and rifampicin resistance were determined at 1 mcg/mL and 50 mcg/mL, respectively. The results were as follows. (1) Most patients with drug-resistant pulmonary tuberculosis were middle-aged or past middle-aged. (2) There were many cases of drug-resistant pulmonary tuberculosis in previously treated tuberculosis patients with active disease and several cases in previously untreated pulmonary tuberculosis patients. However, in some previously untreated patients active tuberculosis was convert relatively easily to inactive tuberculosis. (3) Concerning life style, bachelors who drank heavily were more likely to develop drug-resistant pulmonary tuberculosis. (4) Most cases of drug-resistant pulmonary tuberculosis had at least one cavity on chest radiographs. (5) Several patients with drug-resistant tuberculosis left the hospital against the advice of their attending doctors; therefore, it was difficult to treat their illnesses. (6) In more than half the cases in which Mycobacterium tuberculosis was resistant to isoniazid and rifampicin, tolerance to streptomycin and ethanbutol was also seen. (7) When patients with drug-resistant pulmonary tuberculosis continued to have tuberculous bacilli in their sputum after 3 months of chemotherapy, there was a tendency for them to expectorate tuberculous bacilli in their sputum. For these drug-resistant tuberculosis patients, we must pay attention not only to the medical aspects but also to the social aspects of their disease.

Adult↗
PubMed1995

[Long-term study of patients with pulmonary tuberculosis sequelae after bilateral thoracoplasty-airway obstruction and its causes].

Chest roentgenograms and results of pulmonary-function tests in patients with pulmonary tuberculosis sequelae 30 years after bilateral thoracoplasty were studied retrospectively to detect airway obstruction in these patients and to determine its causes. For periods of more than 10 years, vital capacity (VC) changed at a rate of 15.5 +/- 5.0 ml/year, and forced expiratory volume in one second as a percent of VC (FEV1%) changed at a rate of 0.546% +/- 0.380% per year (n = 13). Thirty years after thoracoplasty, the VC was 920 +/- 180 ml (%VC = 28.4% +/- 5.3%), and the FEV1% was 66.2% +/- 13.7% (n = 21). Thus, mild airway obstruction was found in about half of the cases. For each patient, the distance from the hilum to the diaphragm was measured along the mid-clavicular line on the side with fewer ribs resected, and this distance was divided by the patient's height. The results of that computation was found to be significantly and negatively related to FEV1% (r = -0.681, which suggests that longer bronchi in the lower and middle lobes on that side were associated with lower values of FEV1%. These findings are similar to those in patients with pulmonary tuberculous sequelae after total pneumonectomy. Over an average of 26 years, scoliosis, the vertebra showing the most bending, the intrapulmonary lesion, and the position of the diaphragm did not change, but the cardio-thoracic ratio increased.

Adult↗
PubMed1994

The mutant DnaAcos protein which overinitiates replication of the Escherichia coli chromosome is inert to negative regulation for initiation.

Initiation of chromosome replication occurs excessively in the dnaAcos mutant at 30 degrees C. DnaAcos protein was purified from an overproducing strain and found to be as active as wild-type DnaA protein in initial synthesis rates of minichromosome replication in vitro at 30 degrees C. However, whereas efficient initiation occurred for only 20 min with wild-type DnaA protein, it continued for 45 min with DnaAcos protein, an indication that DnaAcos protein retained initiation activity for a longer time than wild-type DnaA protein. Also, whereas wild-type DnaA protein is inactivated by ADP binding, DnaAcos protein failed to be inactivated by ADP due to its inability to bind nucleotide. Thus, DnaAcos protein appears to lack negative regulation for its initiation activity. At 42 degrees C, a temperature at which initiation of chromosome replication is normal in the dnaAcos mutant, in vitro DnaAcos protein activity decreased to 25% of that observed at 30 degrees C. This coincident occurrence of normal initiation in vivo and reduced activity is consistent with the idea that negative control of DnaA protein activity is necessary for normal replication.

Adenosine Diphosphate↗
PubMed1994

Species and age-dependent differences of functional coupling between opioid delta-receptor and G-proteins and possible involvement of protein kinase C in striatal membranes.

[D-Ser2,Leu5]-enkephalin-Thr6 (DSLET) and [D-Pen2,5]-enkephalin (DPDPE), both delta-agonists, stimulated the high affinity GTPase in the rat striatal membranes in a naltrindole-reversible manner. Similar stimulation was also observed in the striatal membrane preparations of 16-week-old guinea pigs, while not in those preparations of 4-week-old ones. When calphostin C, a protein kinase C inhibitor, was added to the reaction mixture, DSLET showed a marked stimulation in this activity in 4-week guinea pig striatal membranes. There was no effect of KT5720, a cyclic AMP-dependent protein kinase inhibitor, on such delta-opioid-mediated responses. These findings suggest that protein kinase C is locally involved in the functional uncoupling of delta-receptors to G-proteins in the striatum of young guinea pigs.

Aging↗
PubMed1994

Hyperactive initiation of chromosomal replication in vivo and in vitro by a mutant initiator protein, DnaAcos, of Escherichia coli.

DnaA protein initiates genomic replication in Escherichia coli. A cold-sensitive dnaAcos mutant caused excessive initiation at a restrictive temperature without an increase in the level of DnaA protein. The chromosomal origin (oriC) was essential for the lethality caused by the dnaAcos product. Increased initiation activity was neutralized by multiple copies of oriC on a plasmid (pBR322). OriC plasmids were replicated efficiently in vitro in a crude extract prepared from a dnaAcos mutant, with a specific activity for the DnaAcos protein 8-fold greater than that for the DnaA+ protein in a wild-type extract. OriC-dependent replication in the dnaAcos extract was inhibited by rifampicin and by gyrase inhibitors as was replication in the dnaA+ extract. As a control, replication of single-stranded phage phi X174 DNA, which did not require DnaA protein, was similar in extracts prepared from dnaA+ and dnaAcos cells. Thus, initiation at oriC by DnaAcos protein appears to be highly activated both in vivo and in vitro.

Bacterial Proteins↗
PubMed1994

Noninvasive evaluation of cytochrome c oxidase activity of the liver. Its prognostic value for hepatic resection.

OBJECTIVE: To clarify the relationship between the noninvasive evaluation of hepatic mitochondrial function, the redox tolerance test, and cytochrome c oxidase activity of the liver, focusing on surgical risk in hepatic resection. DESIGN: Six-month randomized clinical trial. SETTING: Inpatients in surgical department. STUDY PARTICIPANTS: Forty patients who underwent hepatic resection (n = 36) and other abdominal operations (n = 4). INTERVENTION: Preoperative, noninvasive: The redox tolerance test, which measures the changes in arterial ketone body ratio in response to 75 g of oral glucose loading. Intraoperative, invasive: Cytochrome c oxidase activity and energy charge of the liver. MAIN OUTCOME MEASURE: Correlation of the index in the redox tolerance test (RTI) with cytochrome c oxidase activity, both of which predict the postoperative course. RESULTS: The RTI values were negatively correlated with the maximal velocity (Vmax) and Michaelis constant (Km) values of cytochrome c oxidase activity. The maximal velocity and Michaelis constant values in patients with RTI values above or equal to 0.5 (group A, n = 29) were significantly lower than those in patients with RTI values below 0.5 (group B, n = 11). Eight (72.7%) of 11 patients in group B experienced postoperative complications. CONCLUSION: The RTI is a noninvasive method of assessing the hepatic energy metabolism and can be a useful index for evaluating surgical risk in hepatectomy.

Adenine Nucleotides↗
PubMed1994

Quantitative analyses of the structure-hydrophobicity relationship for N-acetyl di- and tripeptide amides.

The partition coefficient (P) of neutral species and the apparent partition ratio (P') at pH 7 of the ionized form were measured with the 1-octanol/water system for a number of N-acetyl di- and tripeptide amides having un-ionizable and ionizable side chains. Their log values were studied in terms of free-energy-related substituent and substructural parameters using regression analysis to give correlation equations of high quality physicochemically as well as statistically. The intrinsic hydrophobicity of side-chain substituents and their steric effect on the relative solvation of the backbone CONH groups were significant in determining the log P values of the un-ionizable acetyl peptide amides. For the log P value of peptides with polar side-chain substituents, respective indicator variable terms were required to account for the sum of specific effects of substituents such as intramolecular hydrogen-bond formation and the "polar proximity factor" for augmentation of the hydrophobicity. For the log P'(pH 7) value of basic and acidic peptides, the ability of counterionic species to form ion-pairs, the change in the apparent hydrophobicity of ionizable groups from the intrinsic value for their nonionized forms, the effect of ion-pairing itself, and other effects were additionally considered. From the regression coefficients of the parameter terms in correlation equations an effective hydrophobicity index was defined for each side chain, and the application and its limitation were suggested.

Acetylation↗
PubMed1994

Quantitative structure-hydrophobicity and structure-activity relationships of antibacterial gramicidin S analogs.

The structure-hydrophobicity-antibacterial activity relationships of gramicidin S and its analogs retaining a beta-pleated sheet structure were examined quantitatively with physicochemical substituent and molecular parameters using regression analyses. Variations in their apparent hydrophobicity in an octanol/buffer (pH 7) system, log P' (O/W), were analyzed in terms of the "effective" hydrophobicity and steric parameters of side chain substituents of residues at certain positions in the molecule; however, some of the conformational factors have not been fully defined. For the partitioning into liposomes and the growth inhibitory activity against species of Gram-positive bacteria, the log P' (O/W) value simulated the hydrophobic effects of gramicidin S and its analogs better than substituent parameters. The side chain hydrophobicity was assumed to work together with effects attributed to variations in the entire cyclic peptide structure including conformational components undefined in the structure-log P' (O/W) analysis in these activities.

Amino Acid Sequence↗
PubMed1994

Bone marrow scintigraphy in the diagnosis of bone metastasis in prostate cancer.

We investigated bone marrow scintigraphy in 20 patients with prostate cancer to determine the usefulness of this procedure in the diagnosis of bone metastasis. Thirteen of 17 patients whose bone scans revealed hot spots showed accumulation defects in bone marrow scintigrams. Follow-up study and X-ray, computed tomography and/or magnetic resonance imaging findings confirmed the presence of bone metastases in these patients. On the other hand, 4 patients with abnormal bone scans had normal bone marrow scintigrams, and were subsequently demonstrated to have degenerative changes of the spine. Bone marrow scanning therefore appears to be useful in distinguishing metastatic lesions from degenerative changes in cases with suspected bone lesions.

Aged↗
PubMed1994

Sclerotherapy of hydroceles with polidocanol.

Fifteen patients with hydroceles of the testis or spermatic cord were treated by aspiration and injection of the sclerosant solution polidocanol. The cure rate of hydroceles after one sclerotherapy session was 73%, and the overall cure rate using the procedure was 87%. No patient experienced pain during or after the procedure, which was conducted without anaesthesia. No complications were observed. It is concluded that sclerotherapy of hydroceles with polidocanol may be a useful alternative to open operation, due to its ease of administration, low frequency of complications, and high rate of effectiveness, and that this agent is preferable to certain other drugs in that it causes no pain during or after the injection.

Adult↗