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Biomedical subjects

Y Asada

Publications and source records attributed to Y Asada.

At least 163 records · Page 9Linked to original sources
PubMed1995

Activity of eight fluoroquinolones against both methicillin-susceptible and -resistant Staphylococcus aureus isolated from skin infections.

The in vitro susceptibility of Staphylococcus aureus to eight fluoroquinolones, norfloxacin, ofloxacin, enoxacin, ciprofloxacin, lomefloxacin, tosufloxacin, sparfloxacin, and nadifloxacin was established by agar dilution tests, 71 isolates of methicillin-susceptible (MSSA) and 74 isolates of -resistant S. aureus (MRSA) isolated from skin infections. Among all of the fluoroquinolones, nadifloxacin exhibited the lowest MIC for both MSSA and MRSA. In addition, there were no resistant S. aureus, neither MSSA and MRSA, to nadifloxacin. With the exception of nadifloxacin, the incidence of MRSA resistant to fluoroquinolones has gradually increased in recent years. Over half of the MRSA strains were resistant to norfloxacin, ofloxacin, enoxacin, ciprofloxacin, and lomefloxacin.

Anti-Infective Agents↗
PubMed1995

Staphylococcus aureus isolated from nostril anteriors and subungual spaces of the hand: comparative study of medical staff, patients, and normal controls.

An epidemiologic investigation of methicillin-resistant Staphylococcus aureus (MRSA) and Staphylococcus aureus (S. aureus) colonization was conducted at Kansai Medical University Hospital between 1990 and 1991. The incidence of nasal and subungual positivity for S. aureus was examined in a total of 156 subjects including inpatients, physicians, and nurses at a ward for dermatology, plastic surgery, and emergency patients, outpatients with atopic dermatitis and other skin diseases, and normal controls. Inpatients were most heavily colonized with MRSA (40.8%), but S. aureus colonization was most frequent in outpatients with atopic dermatitis (95.5%). Not only nostrils, which have been much discussed as a reservoir of S. aureus, but also subungual spaces seemed to be havens of S. aureus. Twelve out of 22 atopic dermatitis patients were positive for S. aureus on skin regions, and coagulase and phage testing showed a correlation between the nasal and skin-colonizing S. aureus. Coagulase type II and phase type NT (not typable) were the predominant types of S. aureus, including MRSA.

Dermatitis, Atopic↗
PubMed1995

Serum levels of soluble CD23 in patients with bullous pemphigoid.

In this study, we tested the serum levels of soluble CD23 (sCD23) in 27 bullous pemphigoid (BP) patients and compared them with the disease activity. Soluble CD23 is the cleaved portion of the low affinity Fc receptor for IgE (Fc epsilon RII/CD23) which has an affinity for IgE and regulates IgE synthesis. Although bullous pemphigoid (BP) is a subepidermal blistering disease characterized by IgG class autoantibodies against the basement membrane of stratified squamous epithelia, several IgE-related phenomena have been reported. Recently, we have shown that Fc epsilon RII-expressing and IgE-bearing cells are detectable in the lesional skin and concluded that an IgE-Fc epsilon RII/CD23 system may be involved in the pathogenesis of this disease. The serum level of sCD23 in BP patients was significantly higher than healthy controls (p < 0.01). In 11 out of 12 patients, the alteration of serum sCD23 levels correlated well with the disease activity. Thus the serum level of sCD23 is useful as a new parameter for assessing the level of disease activity in BP. High levels of sCD23 may represent part of an IgE-mediated immune reaction which may play a role in the pathogenesis of BP.

Anti-Inflammatory Agents↗
PubMed1995

Pulmonary tumor thrombotic microangiopathy.

Pulmonary tumor thrombotic microangiopathy (PTTM) is characterized by widespread fibrocellular intimal proliferation of the small pulmonary arteries and arterioles in patients with metastatic carcinoma. Microscopic pulmonary tumor emboli have frequently occurred in patients with malignant tumors; however, few cases of PTTM have been reported. A rare case of a patient with gastric adenocarcinoma who presented with acute dyspnea and lethal respiratory failure is described. Histologically, diffuse fibromuscular intimal thickening causing luminal stenosis and obstruction but containing rather few cancer cells was observed in the small pulmonary arteries and arterioles. These findings were consistent with PTTM. Although PTTM is a rare phenomenon, PTTM should be considered in the differential diagnosis of acute dyspnea or pulmonary hypertension in patients with carcinoma.

Adenocarcinoma↗
PubMed1995

The role of endothelin-1 in regulating human granulosa cell proliferation and steroidogenesis in vitro.

The effects of endothelin-1 (ET-1) on luteinized human granulosa cells (L-HGCs) have not been examined. It is well known that there are differences of actions of several autocrine/paracrine regulators between L-HGCs and GCs of other species, and therefore the present study was designed to examine the effects of ET-1 1) on intracellular Ca2+ concentrations ([Ca2+]i) using the Ca(2+)-responsive fluorescent indicator Fura-2, 2) on cell proliferation by the nonradioactive method using bromodeoxyuridine, and 3) on basal and gonadotropin-stimulated steroidogenesis, and to examine the expression of ET receptor messenger RNA (mRNA) using freshly isolated and cultured L-HGCs obtained from patients undergoing in vitro fertilization. ET-1 increased [Ca2+]i in L-HGCs in a dose-dependent manner between 1 and 1000 nmol/L. High concentrations (100-1000 nmol/L) of ET-1 produced a more rapid and transient increase in [Ca2+]i than that observed with low concentrations (1-10 nmol/L) of ET-1. The increase in [Ca2+]i elicited by ET-3 (1000 nmol/L) and IRL-1620 (1000 nmol/L), a selective ETB receptor agonist, was 16% and 3% (vs. ET-1, 100%), respectively. BQ-123 (1000 nmol/L), an ETA receptor antagonist, inhibited the increase in [Ca2+]i elicited by ET-1 (by 50% at 1000 nmol/L ET-1 and by > 90% at < 500 nmol/L ET-1). mRNAs for the two known receptor subtypes (ETA and ETB) were also present in L-HGCs; however, the expression of ETA receptor mRNA was much greater than that of ETB receptors. ET-1 stimulated cell proliferation in L-HGCs in a dose-dependent manner (1000 nmol/L, 210.5 +/- 13.1%; 100 nmol/L, 198 +/- 11%; 10 nmol/L, 146 +/- 18%; and 1 nmol/L, 103 +/- 9%; vs. control, 100%). These stimulatory effects were completely blocked by BQ-123 (1000 nmol/L). ET-3 and IRL-1620 had no effects on cell proliferation in L-HGCs. Significant stimulatory effects on cell proliferation by the calcium ionophore, ionomycin (10-1000 nmol/L), were observed. ET-1, ET-3, and IRL-1620 attenuated basal progesterone secretion in L-HGCs. These results suggest that ETA receptor predominantly exist in L-HGCs and that ET-1 may stimulate cell proliferation of L-HGCs by increasing [Ca2+]i via ETA receptors.

Calcium↗
PubMed1995

Cloning, sequencing, and heterologous expression of a gene coding for Arthromyces ramosus peroxidase.

To understand the relationship between the structure and functions of the peroxidase of Arthromyces ramosus, a novel taxon of hyphomycete, and the evolutionary relationship of the A.ramosus peroxidase (ARP) with the other peroxidases, we isolated complementary and genomic DNA clones encoding ARP and characterized them. The sequence analyses of the ARP and cDNA coding for ARP showed that a mature ARP consists of 344 amino acids with a N-terminal pyroglutamic acid preceded by a signal peptide of 20 amino acid residues. The amino acid sequence of ARP was 99% identical to that of the peroxidase of Coprinus cinereus, a basidiomycete, and also had very high similarities (41-43% identity) to those of basidiomycetous lignin peroxidases, although we could find no lignin peroxidase activities for ARP when assayed with lignin model compounds. We could identified His184 and His56 as proximal and distal ligands to heme, respectively, and Arg52 as an essential Arg. Comparison of the sequences of complementary and genomic DNAs found that protein-encoding DNA is interrupted by 14 intervening sequences. The ARP cDNA was expressed in the yeast Saccharomyces cerevisiae under the promoter of the glyceraldehyde 3-phosphate dehydrogenase gene, yielding 0.02 units/ml of a secreted active peroxidase.

Base Sequence↗
PubMed1995

[Allergy histories of Brazilian residents of Japanese descent in Japan].

A questionnaire written in Portuguese was administered from December 1993 to February 1994 to study the frequency of allergic symptoms among Brazilians of Japanese descent in Japan. The results obtained were as follows. 1) The frequencies of allergy histories were 18% for allergic rhinitis, 14% for atopic dermatitis, 12% for alimentary allergy, 10% for allergic conjunctivitis, 9% for allergy to metals, 8% for drug allergy, 7% each for urticaria and pollinosis, and 5% for asthma. 2) The frequencies of allergic rhinitis, allergic conjunctivitis, pollinosis, urticaria and drug allergy were higher among those who came from metropolitan districts in Brazil with severe environmental pollution compared to those who came from rural districts. 3) The characteristics of persons who had subjective symptoms of pollinosis in early spring during their stay in Japan were as follows: The districts they resided in while in Japan were in the Kanto area where the frequencies of Japanese-cedar pollen-specific IgE antibodies positives were high and also where the frequencies of Japanese cedar pollinosis were high among Japanese living in Japan. The districts they originally came from were the metropolitan areas in Brazil, and they were resident in Japan for more than one year.

Adult↗
PubMed1995

[Immunohistochemical study of transforming growth factor-beta and central fibrosis in T1 adenocarcinoma of the lung].

Transforming growth factor-beta (TGF-beta) is known as the growth factor that stimulates the multiplication and accumulation of extracellular matrix. Recently, TGF-beta also has been found to have the ability to control the growth and metastatic potential of cancer cells. It is known that central fibrosis frequently occurs in pulmonary adenocarcinoma and the prognosis becomes poorer as fibrosis become more hyalinized. To estimate the role of TGF-beta in the formation of central fibrosis in pulmonary adenocarcinoma and its influence on the prognosis of patients with pulmonary adenocarcinoma, we performed an immunohistochemical study of TGF-beta in 51 cases of T1 pulmonary adenocarcinoma. Positive stain for TGF-beta was shown in 31 cases, and negative stain was shown in 20 cases. In patients with Stage I, T1 pulmonary adenocarcinoma, the post operative survival curve was compared between positive and negative cases of TGF-beta, and the result showed a tendency toward poorer prognosis in positive cases of TGF-beta. Twenty-four of 51 cases of T1 pulmonary adenocarcinoma had central fibrosis. Twenty of 24 cases with central fibrosis showed positive stain for TGF-beta. It was proven that the appearance of central fibrosis was significantly related to positive stain for TGF-beta in T1 pulmonary adenocarcinoma. According to these results, it is suggested that TGF-beta plays some role in the formation of central fibrosis in pulmonary adenocarcinoma and TGF-beta is possibly a prognostic factor for patients with pulmonary adenocarcinoma.

Adenocarcinoma↗
PubMed1994

Relationship between serum prostate specific antigen and histological prostatitis in patients with benign prostatic hyperplasia.

The relationship between the serum values of prostate specific antigen (PSA) and the extent of histological prostatitis was investigated in 42 patients undergoing transurethral resection of the prostate for benign hyperplasia (BPH) without clinical evidence of prostatitis. Histological prostatitis was divided into three groups: acute, chronic-active, and chronic-inactive inflammation. The extent of histological prostatitis was expressed as the number of prostatic acinar and ductal glands with inflammatory infiltrate per total number of glands (%). The serum PSA values significantly correlated with the extent of acute and chronic-active prostatitis (correlation coefficient r = 0.765 and 0.656, P < 0.01). A relationship between PSA values and the extent of chronic-inactive prostatitis was not found. In the immunohistochemical study, prostatic epithelial cells with acute and chronic-active inflammation showed negative staining for PSA antigen. These results indicate that histological acute and chronic-active prostatitis is considered an important factor for inducing the high increase in serum PSA values via the leak phenomenon.

Aged↗
PubMed1994

Functional relation between nitric oxide and noradrenaline for the modulation of vascular tone in rat mesenteric vasculature.

As previously reported, N omega-nitro-L-arginine (L-NNA), an inhibitor of nitric oxide (NO) synthesis, decreased transmural field stimulation (TFS)-induced noradrenaline overflow from the isolated perfused rat mesenteric vasculature attached to the intestine. The decrease was attenuated by L-arginine. This suggests that NO may increase noradrenaline release (Yamamoto et al. 1993). The present experiments with this preparation were done in order to monitor changes in vascular perfusion pressure caused by TFS or by noradrenaline infusion in parallel with those in the noradrenaline outflow caused by TFS in the presence of atropine (0.1 mumol/l) (to block acetylcholine-induced release of endothelial NO) and of indomethacin (3 mumol/l) (to inhibit L-NNA-induced production of vasoconstrictor prostanoids). (1) TFS (2-10 Hz) caused a frequency-dependent increase in noradrenaline overflow and perfusion pressure. (2) L-NNA (10 and 30 mumol/l) caused a concentration-dependent inhibition of TFS-induced noradrenaline overflow, whereas the TFS-induced pressure increase was augmented by L-NNA in a concentration-dependent manner. At any given concentration of L-NNA, the potentiation of vasoconstriction by L-NNA became greater in magnitude as the frequency of the TFS was raised. (3) Infusion of noradrenaline (0.38-6 nmol) caused a dose-dependent increase in perfusion pressure up to a value comparable with that caused by TFS. The pressure increase in response to noradrenaline infusion was also enhanced by L-NNA, relatively, to a greater extent than the enhancement, by L-NNA, of the pressure response to TFS.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1994

Endoscopic resection of large colorectal polyps using a clipping method.

PURPOSE: In conventional endoscopic snare polypectomy, bleeding and perforation are the principal concerns. To prevent these complications, we employ an endoscopic clipping technique using the HX-3L clipping apparatus. METHODS: With this method, clips are used to clamp the base of a polyp. A snare is hung peripheral to the clips. The polyp is then resected by coagulating and cutting with an electric current. RESULTS: Neither bleeding nor perforation during or after polypectomy has occurred, nor have complications related to the use of clips developed. Gigantic polyps were not resected piecemeal, but rather were resected en bloc facilitating a clear determination of cancer on the surface of the resected site. Endoscopic clipping permitted site marking for colonoscopic surveillance. CONCLUSION: We conclude that the clipping method has many advantages and is a useful technique in colonoscopic polypectomy.

Adult↗
PubMed1994

Posterior mediastinal endodermal sinus (yolk sac) tumor in a female patient.

Primary endodermal sinus tumor (yolk sac tumor) of the mediastinum is uncommon. Most patients are young and male, and the great majority of tumors are found in the anterior mediastinum. We report a case of primary posterior mediastinal endodermal sinus tumor occurring in a female patient. Surgical excision was performed and three courses of combination chemotherapy were subsequently given. The serum alpha-fetoprotein level returned to normal.

Adolescent↗
PubMed1994

Phototoxicity and photoallergenicity of quinolones in guinea pigs.

Clinical reports indicate that the fluoroquinolone group of antibiotics can induce cutaneous photosensitivity reactions. In the present study, phototoxicity and photoallergenicity of quinolones including nalidixic acid (NA) norfloxacin (NFLX), ofloxacin (OFLX), enoxacin (ENX), ciprofloxacin (CPFX), lomefloxacin (LFLX), and tosufloxacin (TFLX) were experimentally examined in an in vivo system using the guinea pig. Phototoxicity of all quinolones tested was demonstrated after a single, oral administration of the drugs and subsequent exposure to long-wave ultraviolet (UVA) at a dose of 30 J/cm2. The phototoxic potencies were: ENX, LFLX > OFLX > NA, TFLX > NFLX, CPFX. Photoallergic reaction was also induced to LFLX and NA by pretreatment with cyclophosphamide, an immunoadjuvant. No cross-reactions in photoallergy were observed among quinolones. The photo-ingestion test was positive in photoallergically sensitized animals, while the photopatch test was negative. This is the first report which demonstrated experimentally the photoallergenicity of quinolones. Clinical features of the photosensitivity due to quinolones can be explained by the results of the present experiments.

4-Quinolones↗
PubMed1994

Inhibitory effects of prostacyclin analogue, TFC-132, on aortic neointimal thickening in vivo and smooth muscle cell proliferation in vitro.

Effects of a new prostacyclin analogue, TFC-132, on neointimal thickening following intimal mechanical injury and on the proliferation of cultured aortic smooth muscle cells (SMCs) were studied. The intimal injury was induced by indwelling of polyethylene tubing for 24 h in the rabbit aorta. Rabbits were killed 10 days after drawing out the tubing. TFC-132 (0.6 mg/kg or 1.2 mg/kg) was given orally at 8-h intervals through the experiment. The serum concentrations of the analogue rose significantly 1 and 2 h after administration. The mean intimal thickening in the TFC-132 treated groups was significantly thinner than in the control one. Human aortic SMCs were cultured and 3H-thymidine incorporation into DNA (DNA synthesis) was measured at the varying concentrations of TFC-132. The analogue inhibited DNA synthesis of cultured SMCs at 10(-6) and 10(-5) M. These data indicate that a new prostacyclin analogue, TFC-132, has an inhibitory effect on the neointimal thickening after intimal injury and on the aortic SMC proliferation.

Animals↗
PubMed1994

Acylated saponins, masonosides A-C, from the corms of Crocosmia masoniorum.

Three novel triterpenoid saponins, named masonosides A-C, were isolated from the corms of Crocosmia masoniorum. On the basis of spectral and chemical evidence, the structures of masonosides A-C were elucidated as 3-O-[alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranosyl]-28-O- (2-O- [beta-D-apiofuranosyl-(1-->4)-beta-D-xylopyranosyl-(1-->4)- alpha-L-rhamnopyranosyl]-3-O-(beta-D-glucopyranosyl)-4-O-(2-hydroxy-9-ox o-16- alpha-L-rhamnopyranosyloxyhexadecanoyl)- beta-D-fucopyranosyl)-polygalacic acid, 3-O-[alpha-L-arabinopyranosyl-(1-->6)- beta-D-glucopyranosyl]-28-O-(2-O-[beta-D-apiofuranosyl-(1-->4)-bet a-D- xylopranosyl-(1-->4)-alpha-L-rhamnopyranosyl]- 3-O-(beta-D-glucopyranosyl)-4-O-(2,16-dihydroxy- 9-oxohexadecanoyl)-beta-D-fucopyranosyl)-polygalacic acid and 3-O-[alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranosyl]- 28-O-(2-O-[beta-D-xylopyranosyl-(1-->4)-alpha-L-rhamnopyranosyl]-3-O- (beta-D-glucopyranosyl)-4-O-(2,16-dihydroxy- 9-oxohexadecanoyl)-beta-D-fucopyranosyl)-polygalacic acid, respectively.

Carbohydrate Sequence↗