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Biomedical subjects

S Taguchi

Publications and source records attributed to S Taguchi.

At least 109 records · Page 6Linked to original sources
PubMed1993

Effect of a rare leucine codon, TTA, on expression of a foreign gene in Streptomyces lividans.

Streptomyces are bacteria with a very high chromosomal G+C composition (> 70 mol%) and extremely biased codon usage. In order to investigate the relationship between codon usage and gene expression in Streptomyces, we used ssi (Streptomyces subtilisin inhibitor) as a reporter gene and monitored its secretory expression in S. lividans. In consequence of alteration of the native codons of Leu, Lys and Ser of ssi to minor ones by site-directed mutagenesis, i.e., Leu79-Leu80: CTG-CTC to TTA-TTA, Lys89: AAG to AAA, Ser108-Ser109: TCG-AGC to TCT-TCT, respectively, the production of SSI was reduced remarkably in the case of TTA codons, while it was slightly increased in the case of AAA and almost the same in TCT codons. This conspicuous decrease found for Leu codon replacement was probably due to the low availability of intracellular tRNA(Leu) (UUA), a product of bldA which has been reported to be expressed only during the late stage of growth.

Amino Acid Sequence↗
PubMed1993

Effect of downstream message secondary structure on the secretory expression of the Streptomyces subtilisin inhibitor.

The contribution of downstream message secondary structure to the production of Streptomyces subtilisin inhibitor (SSI) was investigated in Streptomyces lividans 66 using a cloned gene. By deletion analysis, two inverted repeats located downstream from the stop codon in the SSI gene were found to exhibit a marked effect on the amount and homogeneity of SSI gene transcript and, consequently, the efficiency of SSI productivity.

Bacterial Proteins↗
PubMed1993

Improved leader and putative terminator sequences for high-level production of Streptomyces subtilisin inhibitor in Escherichia coli.

A high-level production system in Escherichia coli for an alkaline serine protease inhibitor, termed Streptomyces subtilisin inhibitor (SSI), from S. albogriseolus S-3253 was established by replacing the SSI signal sequence with the OmpA signal sequence using the inducible pIN-III-ompA vector. Significant amounts of recombinant SSI, resulting from accurate cleavage of the OmpA signal peptide, were accumulated in the periplasmic space or excreted into the culture medium. The inhibitory activity of the processed protein against subtilisin BPN' was identical with that of authentic SSI. Furthermore, deletion of one of the putative dual terminators (terminator 1) resulted in a 1.9-fold increase in production. This effect on SSI gene expression efficiency was found to be governed mainly at the transcription level.

Amino Acid Sequence↗
PubMed1993

Screening for thyroid diseases in an iodine sufficient area with sensitive thyrotrophin assays, and serum thyroid autoantibody and urinary iodide determinations.

OBJECTIVE: The present study was designed to investigate the prevalence of thyroid dysfunction and its relation to thyroid autoantibodies and urine iodide concentration in apparently healthy people residing in Sapporo, a city of northern Japan, where the iodine intake is high. DESIGN AND SUBJECTS: Serum TSH and thyroid autoantibodies, and urine iodide were measured in 4110 people (2931 men and 1179 women) (age 45.6 +/- 10.3 years (mean +/- SD)) who were recruited at the hospital for medical examinations. RESULTS: The thyroid autoantibodies were positive in 6.4% of males and 13.8% of females with an age-related increase. Of the people with positive antibodies, 87.2% had normal TSH values (0.15-5.0 mU/l) as measured by a sensitive assay. The prevalence of unsuspected hyperthyroidism as defined by suppressed TSH values was 0.61%, of which 64% was diagnosed as Graves' disease based on positive thyrotrophin receptor antibody results. The prevalence of unsuspected hypothyroidism, as evidenced by supranormal TSH, was 0.68% for males and 3.13% for females with an age-related increase. Of those with hypothyroidism, 45.5% were autoantibody positive. The overall prevalence of Hashimoto's thyroiditis was 13.11% for females and 6.15% for males. The urine iodide levels of hypothyroidism with a positive autoantibody of 38.5 (17.7-83.9) mumol/l and a negative autoantibody of 34.9 (17.9-67.9) mumol/l were both significantly higher than that of normal subjects (26.9 (14.6-49.6) mumol/l) (P < 0.01). When iodine intake was restricted for 6-8 weeks for hypothyroid subjects, the elevated TSH and thyroglobulin and low free T4 levels were reversed in the autoantibody negative but not in the positive group. CONCLUSIONS: This study provides further information on the prevalence of thyroid dysfunction and autoimmune thyroid diseases in an iodine sufficient area. In addition, it suggests that more than half of the patients with unsuspected hypothyroidism were negative for autoantibodies and that the excessive iodine intake may be involved in causing latent hypothyroidism.

Adult↗
PubMed1993

Streptomyces subtilisin inhibitor-like proteins are distributed widely in streptomycetes.

Streptomyces subtilisin inhibitor-like proteins were found to be distributed widely in streptomycetes by using the combination of the convenient, newly developed plate assay system and an established liquid culture assay. Almost all the strains formerly categorized as Streptoverticillium species produced proteins that exhibited inhibitory activity against both subtilisin BPN' and trypsin. N-terminal regions of three purified proteins showed high structural similarity to those of other previously reported SIL inhibitors.

Amino Acid Sequence↗
PubMed1993

[Effect of gentian violet on the elimination of methicillin-resistant Staphylococcus aureus (MRSA) existing in the decubitus region].

Methicillin-resistant Staphylococcus aureus (MRSA) is frequently isolated from skin lesions, such as in the decubitus region. There is a possibility that MRSA through these lesions can spread widely in a hospital. However, local treatment with most antibiotics and antiseptics (povidone-iodine) is not effective to eradicate MRSA from the infected decubitus. We have recently demonstrated that gentian violet (Gv) possessed a bactericidal effect against MRSA isolated from clinical specimens in vitro. This examination evaluated whether or not a topical ointment containing 0.1% Gv is effective to eradicate MRSA which existed in decubitus regions. Decubitus (14 clinical cases, ages 59-87 years) infected with MRSA were treated with 0.1% Gv-ointment once or twice daily after bathing in 0.1% Gv aqueous solution. Although all patients were treated with povidone-iodine and 9 out of 14 patients were given either local or systemic administration of antibiotics, those treatments were not effective to eradicate MRSA from decubituses. However, MRSA was not detectable in all cases within 34 days (average: 10.8 days +/- 2.7) after treatment with 0.1% Gv-ointment. The eradication of MRSA from decubitus areas tended to be delayed, depending upon the size and depth of decubituses (Grade III and IV) and complications such as diabetes mellitus. Skin irritability was not observed in any patients. These results suggest that 0.1% Gv-ointment is a useful material for the treatment of the MRSA-local wound infection. Treatment with Gv-ointment to MRSA-infected decubitus may exhibit a protective effect with regard to infection with MRSA in hospital.

Aged↗
PubMed1993

[Excessive nitrous oxide exhalation by postoperative patients in the recovery room].

Expired nitrous oxide from patients in the recovery room is considered to be the major source of air pollution. We measured expired concentrations of nitrous oxide in three patients and three volunteers. After only 5 minute inhalation of 50% nitrous oxide, it took over 2 hours for exhaled N2O concentration to decrease to 25 ppm in volunteers and after 30 minute inhalation, it took over 4 hours. The patients inhaled 50% nitrous oxide for 60, 165, 150 minutes, respectively and all patients expired nitrous oxide, the concentrations of which exceed 100 ppm over 3 hours. As to the patient who inhaled nitrous oxide for 150 minutes, expired nitrous oxide over 25 ppm was detected 10 hours after the end of anesthesia, and it was 4 ppm even after 20 hours. Any personnel including anesthesiologists and nurses working in the operating room can be exposed to high concentrations of nitrous oxide exceeding the permissible limit of 25 ppm, whenever they take care closely of their patients. We do not have any effective measures to protect us from this kind of air pollution except employing total intravenous anesthesia.

Adult↗
PubMed1993

[An emergency operation for a Jehovah's Witness with ruptured thoracic saccular aneurysm].

A 49-year-old male "Jehovah's Witness" was transferred to our hospital with hypotension, abdominal pain, and abdominal distension, and a diagnosis of ruptured thoracic saccular aneurysm was made. He and his family insisted on having an emergency operation for his ruptured aneurysm without blood transfusion. After an intensive discussion among the patient, his family, surgeons, and the director of the hospital, we performed the operation without blood transfusion. The operation using cardiopulmonary bypass took about five hours under enflurane anesthesia, but he died of circulatory collapse fifteen hours after the end of operation. As there may be various opinions concerning how we should take care of Jehovah's Witness patients, we have to manage them case by case.

Adult↗
PubMed1992

Isolation and partial characterization of SSI-like protease inhibitors from Streptomyces.

We attempted to screen a series of Streptomyces subtilisin inhibitor-like (SIL) proteins among several Streptomyces strains by using a highly sensitive assay system established by us. Of six randomly tested strains, four were found to produce SIL inhibitors as their major secreted proteins, suggesting that they might be distributed in a high frequency among this genus. Three inhibitors exhibited inhibition of both subtilisin BPN' and trypsin. Comparison of the amino terminal sequences of these isolated proteins with those of other reported SIL inhibitors revealed that the beta 1- and beta 2-sheets in SSI were highly conserved.

Amino Acid Sequence↗
PubMed1992

Extracellular production system of heterologous peptide driven by a secretory protease inhibitor of Streptomyces.

The value of a heterologous peptide extracellular production system in Streptomyces using a secretory protease inhibitor, was examined. DNA was synthesized encoding apidaecin 1b (AP1), an interesting antibacterial peptide discovered in lymph fluid of the honeybee, and was joined to the Streptomyces subtilisin inhibitor (SSI) gene via a 12-bp nucleotide sequence corresponding to the amino acid sequence specific for cleavage by blood coagulation factor Xa. The fusion protein (SSI-AP1) could be expressed and excreted efficiently into the medium by culturing S. lividans 66 harbouring a plasmid vector constructed for SSI secretion, into which the synthetic DNA was introduced. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis and amino acid analysis of the purified SSI-AP1 provided reasonable results of molecular size and composition value. Interestingly, SSI-AP1 protein showed bifunctional activity: inhibitory activity of SSI and antibacterial activity of AP1. The inhibitory activity against Escherichia coli could be also detected after the fusion protein was cleaved by factor Xa. The extracellular production system presented here should provide a useful tool for production, analysis of mode of action, and also for genetic improvement of antimicrobial peptides such as apidaecin.

Amino Acid Sequence↗
PubMed1992

Inhibitory effects of the cholecystokinin antagonist loxiglumide on pancreatic exocrine secretion and pancreatic growth in conscious rats.

The effects of cholecystokinin (CCK) receptor antagonist Loxiglumide (CR 1505) on pancreatic exocrine secretion and growth stimulated by chronic bile-pancreatic juice diversion to the ileum were studied in conscious rats. Pancreatic secretion was measured each day at 0900 h for 7 d. Pancreatic flow and protein output were significantly increased 24 h after bile-pancreatic juice diversion. Protein output increased each successive day, reaching maximal values of 3.6-fold above basal by the 6th and 7th d of chronic bile-pancreatic juice diversion. Fluid output reached maximal values of approx. 3.5-fold above basal by the 3rd d of chronic bile-pancreatic juice diversion. Plasma CCK increased threefold above basal levels after 24 h of bile-pancreatic juice diversion and remained three- to fourfold above basal. Intragastric bolus infusion of CR 1505 (50 mg/kg) on the 7th d of chronic bile-pancreatic juice diversion inhibited pancreatic protein and fluid secretion by 80 and 75%, respectively, 60 min after administration and by 52 and 71%, respectively, 5 h later. Pancreatic wet wt after 7 d of chronic bile-pancreatic juice diversion was significantly increased by 56%, and this was completely suppressed by 50 mg/kg of CR 1505 given intragastrically every 12 h. These rests indicate that the rat with chronic bile-pancreatic juice diversion is a useful model to examine both potency and duration of the action of CCK receptor antagonists and show that CR 1505 inhibits pancreatic exocrine secretion and growth induced by endogenous CCK.

Animals↗
PubMed1992

Fibre type composition of the soleus muscle in hypoxia-acclimatised rats.

Fibre type composition in the soleus muscle was studied in second generation male and female Sprague-Dawley rats bred at 460 Torr (hypobaric hypoxia). In control male and female rats (bred at sea level atmospheric pressure) the percentage of slow twitch oxidative (SO) fibres increased, and the percentage of fast twitch oxidative glycolytic (FOG) fibres decreased over time. In male hypoxic rats fibre type composition did not change. However, in female hypoxic rats the percentage of SO fibres increased, and that of FOG fibres decreased over time. The female hypoxic rats had a higher percentage of FOG fibres and a lower percentage of SO fibres than age-matched control rats. These findings indicate that hypoxia-acclimatised rats have a relatively high percentage of FOG fibres, and that this is due to inhibition of the fibre type shift from FOG to SO, which occurs during normal development. Furthermore, there is a sex-related difference in the change in fibre type composition in hypoxia-acclimatised rats.

Acclimatization↗
PubMed1992

[Histological evaluation of intra-arterial infusion and systemic chemotherapy of pancreatic carcinomas].

Histological analyses of 16 autopsies of pancreatic carcinoma [9 cases after intra-arterial infusion chemotherapy (IAC), and 7 cases of systemic chemotherapy (SC)] were performed. Histological effects of chemotherapy (Shimosato) were seen in 15 cases, but less than 5 Grade II a. cases of IAC and 4 cases of SC showed Grade IIa, 3 cases of IAC and 3 cases of SC showed Grade I. The ratio of Grade IIa was almost the same in IAC and SC. But histologically, anaplastic change, sarcomatous change and Bizarre cells, immunohistologically positive to anti-EMA and Vimentin antibody, were dominant in IAC. And clinically, serum tumor markers (CEA, CA19-9) were fewer in almost all the cases in IAC. These results may suggest that the anti-tumor effect of IAC was greater than the histological appearance.

Adenocarcinoma↗
PubMed1992

Effect of hypobaric hypoxia on fiber type composition of the soleus muscle in the developing rat.

The fiber type composition of the soleus muscle was investigated in male Sprague-Dawley rats exposed to hypobaric hypoxia of 460 mm Hg from 5 to 12 weeks of age. The muscle fibers were classified as fast-twitch oxidative (FO) and slow-twitch (S) on the basis of adenosine triphosphatase (ATPase) and succinate dehydrogenase (SDH) reactions. Intermediate fibers (INT) with intermediate ATPase and high SDH reaction intensities were also examined. A type shift of muscle fibers from FO to INT and S was found in the control group during development. After exposure to hypoxia, the hypoxia group had a significantly greater percentage of FO fibers than the age-matched control group. There was no significant change in the total number of fibers in the muscle during development and after exposure to hypoxia. These results indicate that the increased percentage of FO fibers found in the developing rat under hypoxic conditions is due to a hypoxia-induced inhibition of the type shift of muscle fibers from FO to S during development.

Animals↗