Biomedical subjects

S Kurata

Publications and source records attributed to S Kurata.

At least 91 records · Page 5Linked to original sources

PubMed1994

Ringed grafting for an abdominal aortic aneurysm in a 92-year-old patient: report of a case.

We report herein the case of a 92-year-old man with an abdominal aortic aneurysm who underwent successful surgical resection using a ringed graft. His postoperative course was uneventful, and he was discharged after 42 days, following which he attended the outpatient department twice a month for regular check-ups. He finally died of pneumonia which developed from an upper respiratory tract infection 6 months after his operation. Thus, surgical treatment should always be considered when an aneurysm is detected, even in very aged patients for whom the activities of daily living are possible.

Aged↗

PubMed1994

Mechanism of action of androgen in hair follicles.

In order to investigate the mode of action of testosterone (T) on human hair follicles we studied the metabolism of T and localization of androgen receptors in outer root sheath cells (ORSC) and dermal papilla cells (DPC) from different body sites. T was principally metabolized to androstenedione (delta 4) even in beard ORSC as well as epidermal keratinocytes (EK), and the ratio of apparent 5 alpha-reductase (5 alpha-R) to 17 beta-hydroxysteroid dehydrogenase (17 beta-HSD) did not differ between these two kinds of cells. The 5 alpha-R activity in beard DPC was 3 times as high as that in occipital scalp and axillary DPC. The 5 alpha-R of beard DPC exhibited a narrow optimum pH of 5.5, which is characteristic of type 2 enzyme present in androgen target cells. In contrast, 5 alpha-R of DPC from axillary and occipital scalp hair showed a broad optimum pH range between 6.5-9.0 corresponding to type 1 5 alpha-R. Androgen receptors were detected in the DPC of beard and axillary hair follicles, but not in those of occipital scalp hair follicles using immunohistochemical staining with polyclonal anti-androgen receptor antibody. Epithelial cells of the hair bulb were not stained by the antibody. Androgen receptors were also detected in the nuclei of cultured beard and axillary DPC, but the DPC from occipital scalp hair follicles showed little staining with the antibody. We also examined the effects of T on the DNA synthesis and proliferation of cultured ORSC and DPC. T did not have a proliferative effect on either type of cell when cultured alone.(ABSTRACT TRUNCATED AT 250 WORDS)

17-Hydroxysteroid Dehydrogenases↗

PubMed1994

Purification and molecular cloning of cDNA for an inducible antibacterial protein of larvae of a coleopteran insect, Holotrichia diomphalia.

Injection of Escherichia coli into larvae of the coleopteran Holotrichia diomphalia results in the appearance of antibacterial activity in the hemolymph. An antibacterial protein, named holotricin 2, was purified from larvae of this insect and characterized. A cDNA clone for holotricin 2 was isolated and its complete sequence was determined. This protein was found to inhibit the growth of Gram-negative bacteria and to consist of 72-amino acid residues with no cysteine residues. Its amino acid sequence is similar to that of coleoptericine, an antibacterial protein isolated from larvae of the coleopteran Zophobas atratus.

Amino Acid Sequence↗

PubMed1994

A prolyl endopeptidase of Sarcophaga peregrina (flesh fly): its purification and suggestion for its participation in the differentiation of the imaginal discs.

A prolyl endopeptidase that hydrolyses Suc-Gly-Pro-MCA (Suc, succinyl; MCA, methyl-coumaryl-7-amide) was purified to near homogeneity from NIH-Sape-4 cells derived from the flesh fly (Sarcophaga peregrina). The molecular mass of the purified enzyme was 84 kDa, and its activity was inhibited almost completely by 1 mM diisopropyl fluorophosphate (DFP). Immunoblotting and DFP-labeling experiments revealed that the leg imaginal discs of Sarcophaga contained this enzyme as a major serine proteinase. This prolyl endopeptidase is suggested to be involved in the differentiation of imaginal discs, because 2 mM DFP and 0.1 mM N-benzyloxycarbonyl-thioprolyl-thioprolynal-dimethylaceta l (ZTTA), a specific inhibitor for prolyl endopeptidase, inhibited differentiation of the imaginal discs from the eversion to the elongation stage.

Amino Acid Sequence↗

PubMed1994

Purification and molecular cloning of cDNA for an inducible antibacterial protein from larvae of the coleopteran, Tenebrio molitor.

Antibacterial activity was induced in the hemolymph of larvae of the coleopteran Tenebrio molitor by injection of Escherichia coli. An antibacterial protein, named tenecin 1, was purified to homogeneity from the larval hemolymph and characterized. A cDNA clone for tenecin 1 was isolated and its complete sequence was determined. This protein was found to inhibit the growth of Gram-positive bacteria and to consist of 43-amino acid residues including six cysteine residues. The disulfide structure of tenecin 1 was determined by sequencing cysteine containing peptides obtained by digesting tenecin 1 with endopeptidase Lys-C, trypsin, and thermolysin. The amino acid sequence and its disulfide bonds were similar to those of sapecin and sapecin C, antibacterial proteins of Sarcophaga peregrina.

Animals↗

PubMed1994

Successful transplantation of cultured human outer root sheath cells as epithelium.

We used sheets of cultured outer root sheath cells derived from plucked human hair follicles for the epidermal reconstruction of a burn wound of a patient and prepared wounds of athymic mice. The outer root sheath cells obtained from plucked human follicles can grow in serial culture in a defined medium without serum. After seven subcultures within 5 weeks, outer root sheath cells obtained from a single follicle grew approximately 1 x 10(7) cells, which covered a 360-cm2 area of a monolayer sheet. These cultured outer root sheath cells, carried on a bovine atelocollagen sheet (Meipac) or a polyurethane sheet (Tegaderm), were transplanted on a graft bed prepared on the backs of athymic mice. Contraction of the graft beds was prevented by the use of these carriers. Histological examination of the graft removed 2 weeks after transplantation showed four to seven layers of epithelial cells. Both the epidermal granular and horny cell layers were well developed, although the rete ridges were absent. Using the same technique, the sheet of outer root sheath cells with an atelocollagen as a carrier was successfully transplanted onto the granulating site in a burn patient.

Adult↗

PubMed1994

A case of Goltz syndrome presenting as congenital incomplete alopecia.

A 5-year-old Japanese girl had had localized, incomplete hair loss on the scalp, minimal distichia, and a small papillomatous eruption on the right upper eyelid since birth. The diagnosis of Goltz syndrome was made by histological findings such as upward extension of the subcutaneous tissue to the papillary dermis and marked diminution in the thickness of the dermis, although typical linear atrophy-like eruptions and other mesoectodermal dysplasia were absent.

Alopecia↗

PubMed1994

Infantile myofibromatosis: report of two cases.

Two cases of solitary type infantile myofibromatosis (IM) were presented. Case 1 was a 6-month-old male infant with a firm, dark red, fixed tumor on his right knee. A computerized tomographic scan revealed that the tumor was attached to the underlying muscle. Case 2 was a 1-month-old male infant with a tumor on his right knee, similar to that in case 1. In neither case was there any clinical evidence of visceral involvement. Histological and immunohistochemical findings were similar. The lesions appeared histologically as non-encapsulated nodules composed of whorled fascicles of spindle-shaped cells and a vascular element with a hemangiopericytoma-like appearance. The tumor cells were positively stained with PTAH. They were positive for alpha-smooth muscle actin and vimentin, but negative for desmin. These findings support the myofibroblastic nature of IM. In case 2, the tumor regressed spontaneously at the age of 12 months. Unlike the multicentric form, spontaneous regression of the solitary form of IM has not previously been reported.

Hemangiopericytoma↗

PubMed1994

Gas gangrene following sacral pressure sores.

We report two cases of gas gangrene developed from sacral pressure sores. The first case was clostridial and the second, non-clostridial gas gangrene. Both patients died within two months. The first patient, a 56-year-old woman suffering from palsy of the lower half of the body for 3 weeks, developed a sacral pressure sore. One month later, crepitus by palpation and gas formation in the X-ray film were detected in the hip and right thigh. A culture of odoriferous pus yielded Clostridium limosum in addition to Staphylococcus intermedius, Enterococcus faecalis, Pseudomonas aeruginosa, and Bacteroides fragilis. Blood culture yielded Bacteroides fragilis. The patient died 50 days after admission in spite of surgical debridement and aggressive therapy with high doses of antibiotics and hyperbaric oxygen. The second patient, a 70-year-old man suffering from diabetic nephropathy, arteriosclerosis obliterans of the lower limbs, and cerebral infarction, developed a large decubitus ulcer covering the whole sacral area. Crepitus and gas were detected in the soft tissue of the left gluteal region. Almost the entire gluteus maximus muscle was necrotic. Bacteroides fragilis, methicillin-resistant or -sensitive Staphylococcus aureus and Escherichia coli were isolated from the muscle. Bacteroides fragilis was also obtained by blood culture. The patient died on the 72nd day after admission.

Aged↗

PubMed1994

beta-Lactam resistance of motile Aeromonas isolates from clinical and environmental sources.

The MICs of various beta-lactams for 182 isolates of Aeromonas species, i.e., A. hydrophila (n = 101), A. sobria (n = 69), and A. caviae (n = 12), from clinical and environmental sources were determined by an agar dilution technique. All strains were resistant to ampicillin and susceptible to aztreonam. A. sobria and A. caviae demonstrated lower resistance rates than A. hydrophila. Penicillin-hydrolyzing beta-lactamases were detected in all strains.

Aeromonas↗

PubMed1994

The effects of finasteride (Proscar) on hair growth, hair cycle stage, and serum testosterone and dihydrotestosterone in adult male and female stumptail macaques (Macaca arctoides).

Finasteride, a 5 alpha-reductase inhibitor, was administered orally (1 mg/kg.day) for 6 months to six male and five female stumptail macaques. Vehicle was given to five male and five female animals over the same period of time. Hair weights in a defined 1-in.2 area of frontal scalp were measured periodically every 1-2 months, and serum was collected for measurement of testosterone and dihydrotestosterone. In addition, scalp biopsies were taken before and 6 months after treatment to evaluate the micromorphometry of hair follicles. Results showed that both male and female serum dihydrotestosterone levels were significantly reduced (60-70%) by finasteride treatment. Both males and females showed statistically significant increases in mean hair weight over the treatment period compared to controls (P = 0.034). In addition, there was a statistically significant increase in mean follicle length (measured histologically in scalp biopsies) compared to baseline in the finasteride-treated animals (P = 0.028). These data show that an inhibition of 5 alpha-reductase in the stumptail macaque can reverse the balding seen with age in both the male and female animals.

Animals↗

PubMed1993

Molecular cloning of cDNA for the 29 kDa proteinase participating in decomposition of the larval fat body during metamorphosis of Sarcophaga peregrina (flesh fly).

A cDNA clone for the 29 kDa proteinase participating in tissue disintegration during metamorphosis of Sarcophaga was isolated. This proteinase, named Sarcophaga cathepsin B, consisted of 256 amino acid residues, and contained three putative N-glycosylation sites. By comparison with other cathepsins B, its unique substrate specificity was partly explained by Ala at position 248.

Adipose Tissue↗

PubMed1993

Transcriptional control of the heme oxygenase gene during mouse spermatogenesis.

The activation of the heme oxygenase (HO) gene during development of mouse male germ cells was examined by nuclear run-off assay. Results showed that the HO gene was activated in male germ cells, especially in spermatogonia and that the mRNA was stored throughout meiosis. In contrast, Western blotting analysis revealed that HO was expressed during spermatogenesis to spermatocytes. As the mouse HO gene is known to have a 12-o-tetradecanoyl-phorbol 13-acetate(TPA)-responsive element (TRE) in its upstream region and is activated by TPA in mouse M1 cells, we also examined the activation of the nuclear proto-oncogenes fos and jun, which are activators of TRE. Both genes were found to be activated with expression of their protein products only in spermatogonia. Moreover activation of fos, jun and HO genes in spermatogonia was strongly inhibited by a c-kinase inhibitor. These results suggest that the HO gene is activated at the spermatogonia stage by a fos/jun heterodimer complex (AP1) through c-kinase activation.

Animals↗

PubMed1993

Haploid specific activations of protamine 1 and hsc70t genes in mouse spermatogenesis.

Protamine 1 and heat shock cognate 70 kDa protein (hsc70t) are known to be synthesized in haploid cells during spermatogenesis, and the mRNAs of these proteins have also been shown to accumulate in the haploid cells. However, it is unknown at which stage of spermatogenesis the genes for these proteins are actually activated. To examine this problem, we fractionated mouse adult testes cells at four different developmental stages, extracted their nuclei and carried out run-off assays with hsc70t and protamine 1 DNA probes. Results showed that both genes are mainly activated at the round spermatid stage. As the protein products of these genes accumulate at the later stage, it is interesting that these genes are regulated at the transcriptional and translational levels during spermatogenesis.

Animals↗

PubMed1993

Purification, characterization, and cDNA cloning of an antifungal protein from the hemolymph of Sarcophaga peregrina (flesh fly) larvae.

An antifungal protein (AFP) was purified from the hemolymph of third instar larvae of Sarcophaga peregrina. This protein repressed the growth of Candida albicans in Sabouraud medium in the presence of nitrofurazone. However, in distilled water or saline, AFP alone killed C. albicans. Significant synergism was detected between AFP and sarcotoxin IA, an antibacterial protein of Sarcophaga. The lethal effect of AFP on C. albicans was greatly enhanced by the presence of a small amount of sarcotoxin IA. AFP was shown to bind to C. albicans and cause leakage of a substance(s) with absorbance at 260 nm from the cells. Analysis of its cDNA showed that AFP is a novel histidine-rich protein consisting of 67 amino acid residues.

Amino Acid Sequence↗

PubMed1993

Human neuroblastoma cells produce the NF-kappa B-like HIV-1 transcription activator during differentiation.

Human neuroblastoma GOTO and IMR32 cells differentiate into neural cells on treatment with 5-BrdU. Here we report that in association with differentiation induced by 5-BrdU, the transcription of HIV-1 was activated in both neuroblastoma cell lines. An NF-kappa B-like factor was also found to be produced in association with the neural cell differentiation of these cells. These results suggest that, during differentiation of neural cells, an NF-kappa B-like factor was produced, and that when the neural cells are infected with HIV-1 the production of NF-kappa B results in activation of transcription of HIV-1. Thus this NF-kappa B-like factor may be involved in the mechanism causing AIDS dementia.

Base Sequence↗

PubMed1993

Transcriptional activation of type I collagen genes by ascorbic acid 2-phosphate in human skin fibroblasts and its failure in cells from a patient with alpha 2(I)-chain-defective Ehlers-Danlos syndrome.

L-Ascorbic acid 2-phosphate (Asc 2-P), a long-acting vitamin C derivative, stimulated transcription of genes for pro alpha 1(I) and pro alpha 2(I) collagen in normal human skin fibroblasts after 8 h of treatment in the absence or in the presence of cycloheximide, indicating Asc 2-P stimulates transcription of type I collagen genes in the absence of protein synthesis. The transcriptional rate in these cells reached the maximum value after 40 h of treatment, and at that time it was three to four times higher than that of the control cells cultured in the absence of Asc 2-P. Steady-state levels of mRNAs for pro alpha 1(I) and pro alpha 2(I) chains were also increased to be three to four times higher than the control levels by treatment of the cells with Asc 2-P for 72 h. When the fibroblasts obtained from a patient with Ehlers-Danlos syndrome were treated with Asc 2-P, the derivative also stimulated transcription of the gene for pro alpha 1(I) chain and accumulation of mRNA for pro alpha 1(I) chain. On the other hand, Asc 2-P failed to stimulate transcription of the pro alpha 2(I) gene or an increase in mRNA for pro alpha 2(I) chain. Sodium ascorbate showed effects quite similar to those of Asc 2-P, when fibroblasts obtained from a normal control or the patient were cultured for 16 h with it. These results indicate the existence of cis-regulatory elements responsible for transcriptional activation by Asc 2-P or ascorbic acid in pro alpha 1(I) and pro alpha 2(I) genes of normal fibroblasts. These data also suggest some defect(s) of these elements in the pro alpha 2(I) gene of the patient with Ehlers-Danlos syndrome.

Ascorbic Acid↗

PubMed1993

Testosterone metabolism by cultured human beard outer root sheath cells in comparison with epidermal keratinocytes.

In order to elucidate the mechanism of action of androgen in human hair follicles, we studied testosterone metabolism by cultured beard outer root sheath cells in comparison with that of epidermal keratinocytes. When cells were incubated as a monolayer in serum-free keratinocyte growth medium with physiological concentrations (25 nM) of [3H]testosterone, the major metabolite was androstenedione in either type of cells. Small amounts of androstanedione, dihydrotestosterone and androsterone were also formed. The ratio of apparent 5 alpha-reductase to 17 beta-hydroxy-steroid dehydrogenase activities ranged from 0.11 to 0.81 and did not differ between these two kinds of cells. After these cells were cultured in the presence of 10% fetal calf serum for 10 days, the activities of both metabolic pathways markedly increased without significant changes of the ratio of activities of these two enzymes. Thus, testosterone was rather converted to weak androgens even in beard outer root sheath cells under the experimental conditions.

17-Hydroxysteroid Dehydrogenases↗