Biomedical subjects

Y Asada

Publications and source records attributed to Y Asada.

At least 181 records · Page 10Linked to original sources

PubMed1994

Minor desacylsaponins from the corms of Crocosmia masoniorum.

Two novel triterpene saponins, named desacylmasonosides 4 and 5, and a new oxygenated fatty acid have been isolated, together with a known saponin, desacylcrocosmioside A, from the weak alkaline hydrolysate of the crude saponin obtained from the corms of Crocosmia masoniorum. On the basis of spectral and chemical evidence, the structures of desacylmasonosides 4 and 5 were elucidated as 3-O-[beta-D-fucopyranosyl-(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)-beta-D-fucopyranosyl)-po lygalaci c acid and 3-O-[alpha-L-arabinopyranosyl-(1-->6)-beta-D-glucopyranosyl]-28-O- [2-O-(alpha-L-rhamnopyranosyl)-3-O-(beta-D-glucopyranosyl)-beta-D- fucopyranosyl]-polygalacic acid, respectively. An oxygenated fatty acid derived from the acyl moiety of the esterified saponins was identified as 2,16-dihydroxy-9-oxohexadecanoic acid.

Carbohydrate Sequence↗

PubMed1994

Cockayne syndrome in two adult siblings.

Although survival beyond the second decade is unusual in patients who have Cockayne syndrome, we describe two brothers with the syndrome who are 42 and 55 years of age. Their cultured skin fibroblasts showed extreme UV sensitivity but had almost normal UV-induced unscheduled DNA synthesis. The patients were classified as genetic complementation group B after study of the recovery of RNA synthesis after UV irradiation of fused cells. Clinical phototesting revealed a reduced threshold for UVB erythema.

Adult↗

PubMed1994

A mutation in the Ter gene causing increased susceptibility to testicular teratomas maps to mouse chromosome 18.

Little is known about inherited susceptibility to spontaneous germ cells tumours in humans or other species. The Ter mutation in laboratory mice is novel in that it acts codominantly to reduce germ cell numbers on many inbred strain backgrounds and to enhance dramatically inherited predisposition to spontaneous testicular teratocarcinomas in strain 129 inbred mice. We have adopted a PCR-based, DNA pooling method for mice with 'extreme' phenotypes (small testes versus normal-sized testes) to identify a candidate linkage to the Ter locus. Two independent mapping approaches confirmed this evidence for Ter linkage near D18Mit62 on mouse chromosome 18, and suggest a possible human homologue on chromosome 5q.

Animals↗

PubMed1994

Method for selecting anthocyanin-producing cells by a cell sorter.

We found a novel method to select anthocyanin-producing cells by a new means of cell staining. After staining with 0.2 ppm fluorescein isothiocyanate (FITC), the protoplasts from Aralia cordata cultured cells, which were composed of high anthocyanin-producing cells and non-producing cells, were observed to be distinguishable under a fluorescence microscope. The green fluorescence of FITC from the non-producing cells was clearly ascertained by the naked eye. On the other hand, the fluorescence of the anthocyanin-producing cells was completely missing. This phenomenon resulted from compensation of the green fluorescence (lambda max 525 nm) of FITC and the green light absorption (lambda max 530 nm) of anthocyanin. Although investigations of the flow cytometric method were developed on the basis of this phenomenon, the histograms of these protoplasts expressed the distinction between the anthocyanin-producing cells and the non-producing cells. In order to prove the technique, a highly productive cell line was selected from the heterogeneous populations of anthocyanin-producing or non-producing protoplasts from A. cordata cultured cells. The number of the sorted protoplasts containing anthocyanin was counted by the naked eye, the anthocyanin-producing protoplasts were approximately 90% in the whole protoplasts and the viability was 60-70%. Anthocyanin concentration the sorted protoplasts was 3-fold higher as compared with the protoplasts before sorting. The anthocyanin content of the cell line selected by this method was 7.7 +/- 0.6%/g dw.(ABSTRACT TRUNCATED AT 250 WORDS)

Anthocyanins↗

PubMed1994

Suramin inhibits intimal thickening following intimal injury in the rabbit aorta in vivo.

OBJECTIVE: Proliferation of vascular smooth muscle cells is a major event in atherogenesis. Several growth factors have been well documented to control this proliferation. Inhibition by suramin of the binding of some growth factors to their receptors has recently been reported. The aim of this study was to examine the effects of this agent on neointimal thickening following intimal mechanical injury, as well as on platelet function. METHODS: Intimal thickening was induced by indwelling of polyethylene tubing for 24 h in the rabbit aorta. Rabbits were killed 10 d after drawing out the tubing. Throughout the experiment, suramin (15 mg.kg-1) was injected intravenously every 24 h. Morphological and morphometrical studies were performed in the suramin treated group (n = 6) and in a control group (n = 6). Platelet-rich plasma was prepared from animals before and 3 h after injection of suramin. Platelet aggregation and ATP release induced by collagen were examined. Platelet adhesion on the de-endothelialised area of the rabbit aorta was also examined in the two groups. RESULTS: The mean intimal thickening in the suramin treated group was significantly less than in the control group. Smooth muscle cell replication and cell density in the thickened intima of the suramin treated group were less than in control. Suramin did not affect collagen induced platelet aggregation, ATP release, or platelet adhesion. CONCLUSIONS: Suramin has an inhibitory effect on the neointimal thickening and intimal smooth muscle cell proliferation after intimal injury in the rabbit aorta, but has no effect on platelet function.

Animals↗

PubMed1994

The antibiotic susceptibility of Propionibacterium acnes and Staphylococcus epidermidis isolated from acne.

We studied the susceptibility of antimicrobial agents to Propionibacterium acnes (P. acnes) and Staphylococcus epidermidis (S. epidermidis) isolated from acne patients. We measured the minimum inhibitory concentrations (MICs) of the following five drugs: roxithromycin (RXM), erythromycin (EM), clindamycin (CLDM), minocycline (MINO) and ofloxacin (OFLX), which are frequently used to treat acne and skin infections. We found many resistant strains of S. epidermidis and some resistant strains of P. acnes. There was a correlation between the resistance of S. epidermidis and the former therapy for acne, but no distinct correlation between the resistance of P. acnes and the former therapy for acne.

Acne Vulgaris↗

PubMed1994

Sensitivity of Staphylococcus aureus and Streptococcus pyogenes isolated from skin infections in 1992 to antimicrobial agents.

We studied the efficacy of antimicrobial agents against Staphylococcus aureus (S. aureus) and Streptococcus pyogenes (S. pyogenes) isolated from skin infections in 1992. For S. aureus, we measured the minimum inhibitory concentrations (MICs) of the following 10 drugs: methicillin (DMPPC), cefaclor (CCL), gentamicin (GM), erythromycin (EM), clindamycin (CLDM), minocycline (MINO), vancomycin (VAN), fusidic acid (FA), ofloxacin (OFLX) and nadifloxacin (NDFX); for S. pyogenes, we determined the MICs of the following 9 drugs: ampicillin (ABPC), amoxicillin (AMPC), cefpodoxime proxetil (CPDX-PR), erythromycin (EM), clindamycin (CLDM), minocycline (MINO), norfloxacin (NFLX), of loxacin (OFLX) and nadifloxacin (NDFX). These drugs are frequently used to treat skin infections, either systemically or topically. NDFX is a new synthetic fluoroquinolone, recently developed for use as a topical acne medication in Japan. It is used NDFX for acne, but not for skin infections. There were no strains of S. aureus resistant to NDFX, VAN or FA. The resistance (> or = 12.5 micrograms/ml) of S. aureus was highest to GM and lowest to OFLX. Four strains of methicillin-resistant (> or = 12.5 micrograms/ml) S. aureus (MRSA) were found. In contrast, no resistant strains of S. pyogenes were found except to MINO. Only two strains of S. pyogenes were susceptible to MINO. The sensitivity of S. pyogenes to ABPC, AMPC, CPDX-PR, EM and CLDM was very good. All the strains were susceptible at a MIC below > or = 0.05 microgram/ml. However, the S. pyogenes strains were not very sensitive to the new quinolones, especially NFLX. We concluded that penicillins, cephalosporins and macrolides are still effective against streptococcal infections.(ABSTRACT TRUNCATED AT 250 WORDS)

Anti-Bacterial Agents↗

PubMed1994

Study of the efficacy of antiseptic handrub lotions with hand washing machines.

The effectiveness of quick handwashing in regards to four alcohol-based handrub lotions, including two products already on the market and our original lotions 1, 2, with two different kinds of hand washing machines was studied in vivo. We also tried to evaluate the efficacy of the four lotions in vitro. The in vivo testing of each lotion, including ethanol, was evaluated using two hand washing methods, first with and then without a previous soap wash. Computerized image analysis was used to calculate the bacterial count on the hand surface. The results showed that a 3 second application of the original lotion 2 (0.5% chlorhexidine in a 77% ethyl alcohol solution) preceded by a soap wash eradicated 89.3% of the bacteria on the hands; this was the highest reduction rate of all four detergents. AROKULIN-E (67.9% ethyl alcohol solution) without a prior handwashing produced the lowest reduction, 49.1% against hand surface bacteria. These results were compatible with those in vitro. It seems that an alcohol-based solution containing an effective antimicrobial detergent preceded by a soap wash is necessary to acceptably reduce hand surface bacteria.

Bacteria↗

PubMed1994

An evaluation of the residual activity of antiseptic handrub lotions: an 'in use' setting study.

An evaluation of the residual activity of quick-drying agents (alcoholic solutions) used for hygienic hand disinfection is described. We looked for residual efficacy following hand disinfection with soap and water alone or followed by one of two alcoholic handrub lotions supplied from an automatic hand washing machine. The bacterial counts on the hands obtained before and within 2 successive hours after disinfection showed that alcoholic chlorhexidine was the most effective for 10 minutes after contamination of the hands. WELPAS (alcoholic chlorbenzarconium) followed this in its immediate effect and was better than soap and water alone. There were no significant differences after 30' or 120' between the three disinfecting methods.

Adult↗

PubMed1994

Effects of N omega-nitro-L-arginine and capsaicin on neurogenic vasomotor responses in isolated mesenteric arteries of the monkey.

Monkey isolated mesenteric arterial rings denuded of endothelium constricted upon transmural nerve stimulation (TNS) in the absence of active muscle tone. The constriction was potentiated by N omega-nitro-L-arginine (3 x 10(-5) M), but not by the D-enantiomer (3 x 10(-5) M). The potentiation was reversed by L-arginine (3 x 10(-4) M). The neurogenic vasoconstriction of mesenteric arteries was also augmented by capsaicin, but to a lesser extent than that induced by N omega-nitro-L-arginine. Indomethacin (10(-5) M) did not affect TNS-induced vasoconstriction. These findings suggest that nerve-derived nitric oxide or a related substance may play a greater role than do capsaicin-sensitive vasodilator transmitters in neurogenic regulation of mesenteric arterial tone in the monkey. The transmitter mechanisms for vasodilation in mesenteric circulation vary among species.

Animals↗

PubMed1994

Identification of two point mutations in the gene coding luteinizing hormone (LH) beta-subunit, associated with immunologically anomalous LH variants.

To analyze the structure of LH in three patients with immunologically anomalous LH, the whole coding region of the LH beta-subunit gene was examined. These patients were infertile, and their serum LH levels could not be measured with an immunoassay kit. Immunoblotting of the LH beta-subunit showed no marked changes in the molecular size of LH beta. Genomic DNA was extracted from peripheral lymphocytes of the patients and normal controls, and LH beta genes were amplified by the polymerase chain reaction technique, using primer pairs that are capable of specifically amplifying only the LH beta gene without interference by the CG beta genes. No deletions were observed in the coding regions of the LH beta gene of the patients. Nucleotide sequencing revealed two nucleotide substitutions in the LH beta gene of the patients, which cause amino acid replacements from Trp8 (TGG) to Arg8 (CGG) and Ile15 (ATC) to Thr15 (ACC). Restriction fragment length polymorphism analysis in three families indicated that the affected probands were homozygous, and their family members were heterozygous, except for their husbands. The heterozygotes showed reduced detectability with the LH immunoassay kit. These results suggest that these amino acid replacements are responsible for this immunologically anomalous variant.

Adult↗

PubMed1994

[Thoracoscopic treatment of mediastinal thymic cyst].

A mediastinal thymic cyst was excised under thoracoscope in a 66 year-old man. Mass lesion was noted in the left anterior mediastinum on chest X-p during a screening examination. Based on the findings of the chest CT and MRI, the mass was diagnosed as a cyst containing low fat and low protein fluid without solid tissue. This lesion was diagnosed as a mediastinal thymic cyst. Under general anesthesia, the thoracoscopy was inserted to the left thoracic cavity. Then, the cyst was resected sharply and bluntly with pair of scissors, while electric coagulation was performed as needed. In cases of mediastinal thymic cyst, it is possible to completely resect the cyst by thoracoscopic treatment, causing minimal surgical invasiveness. Considering that a few thymic cysts are combined with malignant tumor, complete resection of the lesion is required in the treatment of thymic cyst.

Aged↗

PubMed1993

N omega-nitro-L-arginine, an inhibitor of nitric oxide synthesis, decreases noradrenaline outflow in rat isolated perfused mesenteric vasculature.

In the isolated perfused rat mesenteric vasculature with intestine attached N omega-nitro-L-arginine (L-NNA) (30 mumol/l), an inhibitor of nitric oxide (NO) synthesis from L-arginine, did not alter spontaneous noradrenaline outflow. Transmural field stimulation (2-10 Hz) caused a frequency-dependent increase in noradrenaline outflow. The evoked overflow was reduced by L-NNA. L-Arginine (0.3 mmol/l) attenuated the inhibition of noradrenaline overflow by L-NNA. These results suggest that NO increases the release of noradrenaline in rat mesenteric vasculature.

Animals↗

PubMed1993

Biotransformation of 18 beta-glycyrrhetinic acid by ginseng hairy root culture.

On administration of 18 beta-glycyrrhetinic acid to hairy root cultures of Panax ginseng, three new biotransformation products, 30-O-[beta-D-glucopyranosyl-(1-->2)-beta-D- glucopyranosyl]18 beta-glycyrrhetinic acid, 30-O-(6- O-malonyl-beta-D-glucopyranosyl)18 beta-glycyrrhetinic acid and 3-O-[6-O- malonyl-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl]18 beta-glycyrrhetinic acid, were isolated together with three known compounds. Ginseng hairy roots showed the biotransformation abilities of glycosylation and malonylation to 18 beta-glycyrrhetinic acid.

Biotransformation↗

PubMed1993

An evaluation, using computerized image analysis, of antimicrobial efficacy of an automatic hand washing machine with ultrasonic wave spraying.

We studied the antimicrobial efficacy of hand washing with a quick-dry hand washing machine [TE-KIREIKI] employing ultrasonic wave spraying and its incidental alcohol-based product [AROKULIN-E]. The subjects of this study were 10 males who had been instructed not to use any antimicrobial agent for the previous 2 weeks or any hand soap for the previous 5 hours. They pressed their palms on agar before and after washing their hands. After 48-hour incubation at 37 degrees C, the bacterial colonies grown on the agar were counted using the [ASPECT] image processing system. The colony count was expressed as the post-stamp versus pre-stamp percent (%) reduction. Two patterns of hand washing were examined in this study: [A] a 3-second hand wash using an alcohol-based product [AROKULIN-E] and [B] a 30-second hand wash using a nonmedicated detergent soap with running water in addition to hand washing by [A]. The percent (%) reduction after hand washing patterns [A] and [B] were 49.1% and 51.3%. These reduction rates indicated that these patterns did not eradicate bacteria from the hand surface. Therefore, we concluded that this quick-dry hand washing machine employing an ultrasonic wave spraying method combined with an alcohol-based product needs improvement.

Bacteria↗

PubMed1993

The incidence of isolation of methicillin-resistant Staphylococcus aureus (MRSA) strains from skin infections during the past three years (1989-1991).

We did a statistical study of 294 strains of Staphylococcus aureus (S. aureus) isolated from skin infections during the period from January of 1989 to December of 1991 in the Department of Dermatology, Kansai Medical University Hospital. We especially examined methicillin-resistant S. aureus (MRSA) from the point of view of incidence, variety of skin infections with MRSA, coagulase type, phase type, and resistance against antimicrobial agents. The frequency of isolation of MRSA has been increasing. In 1991, the proportion of MRSA isolates among all S. aureus strains isolated from skin infections was 41.5%. MRSA was isolated most often from infectious decubitus. Coagulase type II and phage group NT (not typable) MRSA were most frequently isolated. The resistance of MRSA to OFLX and IMP/CS had remarkably increased. Notably, the resistance to MINO was low before 1991.

Adolescent↗

PubMed1993

The effect of ultraviolet (UVB and PUVA) radiation on the expression of epidermal keratins.

Using a panel of monoclonal antibodies directed against keratins (PKK2, CK8.12 and KL1), the effects of ultraviolet B (UVB) and psoralen plus ultraviolet A (PUVA) irradiation on keratin expression in guinea-pig skin were examined immunohistochemically. Following irradiation, whether by UVB or PUVA, rapid alterations in the distribution pattern of keratins were observed in the epidermis. The alterations included the induction of basal cell-type keratins (PKK2 and CK8.12 staining) in the suprabasal layers, with concomitant reduction of the suprabasal-type keratins (KL1 staining). These alterations in keratin expression were observed during the period when DNA synthesis appears to be accelerated by ultraviolet light exposure (5 h-5 days after UVB, and 2-10 days after PUVA irradiation). Therefore, these changes are probably reflections of a proliferative or regenerative state of keratinocytes. This explanation was supported by the result of an experiment involving tape stripping of the epidermal horny layers, which also accelerates DNA synthesis by keratinocytes. Immunohistochemistry appears to be a useful and sensitive method of detecting the effect of ultraviolet light on keratinization.

Animals↗

PubMed1993

IgE and its related phenomena in bullous pemphigoid.

This study was designed to analyse IgE and its related phenomena in bullous pemphigoid (BP). We analysed 17 BP sera by indirect immunofluorescence (IIF) and immunoblotting (IB) using a monoclonal antibody to IgE. In addition, inflammatory cells in lesional skin from 11 patients with BP were analysed by the alkaline phosphatase-anti-alkaline phosphatase (APAAP) technique using monoclonal antibodies to IgE and Fc epsilon RII/CD23. IgE class anti-basement membrane zone (BMZ) autoantibody was detected in nine of 17 sera (52.9%) by IIF. IgG class anti-BMZ antibody could block the BMZ-binding reactivity of IgE class antibody. Titres of IgE class autoantibody in the sera ranged from 1:40 to 1:320, and statistically correlated with serum IgE levels. Two of 11 sera contained an IgE class autoantibody which recognized a 230-kDa BP antigen by IB. By radio-allergosorbent test (RAST), IgE-specific antibodies to an extended series of common inhalant and food allergens were detectable in six sera with high concentrations of total IgE (over 3,300 IU/ml). IgE-bearing and Fc epsilon RII-expressing cells were demonstrated in the upper dermis and along the BMZ in seven of 11 biopsy specimens by the APAAP technique. The distribution and number of IgE-bearing cells in the lesions were similar to those of the Fc epsilon RII-expressing cells. These results suggest that both IgE-mediated immune responses and autoimmunity characterize BP as distinctive features.

Antibody Specificity↗