Biomedical subjects

M Shimozuma

Publications and source records attributed to M Shimozuma.

16 recordsLinked to original sources

PubMed2001

Boltzmann equation description of electron transport in an electric field with cylindrical or spherical symmetry.

The spatially dependent description of the electron kinetics in nonuniform electric fields is of primary importance for the modeling of gas-filled proportional counters and other plasma devices. For a typical example, the amplification of the gain signal in the gas counters is determined by the behavior of electron ionization processes in the cylindrically or spherically symmetric electric field around thin wire or tiny sphere anode. In this paper, the general formalism of the Boltzmann equation in these types of the nonuniform electric fields is presented for specifying the electron swarm dynamics affected by the field geometry. The behavior of electrons in the cylindrical or spherical field configuration is investigated by a Monte Carlo technique to exemplify the description, and the effects associated with the angular momentum of electrons are discussed in terms of the ionization coefficient.

Journal Article↗

PubMed2001

Long-term follow-up study of onychomycosis: cure rate and dropout rate with oral antifungal treatments.

The "complete cure" of onychomycosis requires long-term treatment with a systemic antifungal agent. Therefore, to properly assess the effects of an antifungal agent on onychomycosis requires a long follow-up. We have conducted a retrospective analysis of the patients treated with griseofulvin (GRF) from 1962 to 1992 and a clinical study to compare the long-term effect of GRF with that of a new oral antifungal agent, itraconazole (ITCZ), for patients who received treatment from 1992 to 1995. For the retrospective study, 281 patients who were microscopically diagnosed as having onychomycosis at the Department of Dermatology, Faculty of Medicine, University of Tokyo, and received GRF administration in 1962, 1972, 1982, and 1992, were evaluated for cure rate and dropout rate. The total cure rate was 29.2%, but the cure rate was 68.8% for the patients who continued their medication for more than one year. For the comparative study, 139 patients who received the treatment at the same institution between 1992 and 1995 were evaluated. The cure rate and the dropout rate for GRF were found to be 23.8% (23/97) and 52.6% (51/97) respectively. The cure rate and the dropout rate for ITCZ were found to be 50.0% (21/42) and 38.1% (15/42). When the two treatment protocols were compared for their long-term effects, we found that most of the patients treated with ITCZ were cured within 3 years, and about 30% of the patients treated with GRF remained uncured even after long-term administration of the agent. Furthermore, from a multiple regression analysis, the GRF/ITCZ administration required to cure onychomycosis was estimated to be 3.92 + 0.161 [Age (years)] + 0.635 [Number of infected toenails] months. The results of this study suggest that the biggest problem associated with the treatment of onychomycosis with an oral antifungal agent is compliance in long-term therapy. Notably, the final cure rate of ITCZ therapy went over 90%, suggesting that the low dose continuous therapy, the standard treatment protocol in Japan, was a key contributing factor for the higher cure rate for ITCZ.

Administration, Oral↗

PubMed2000

Case report. Onychomycosis due to Chaetomium globosum successfully treated with itraconazole.

We have experienced a case of toenail infection caused by Chaetomium globosum which we treated with itraconazole 100 mg day-1 for 6 months, after which time the nail lesions were almost cured. Our case is the first reported case of onychomycosis caused by Ch. globosum in Japan, and the seventh in the world.

Antifungal Agents↗

PubMed1997

Prevalence and clinical relevance of 52-kDa and 60-kDa Ro/SS-A autoantibodies in Japanese patients with systemic sclerosis.

OBJECTIVE: To determine the prevalence of 52-Kda and 60-Kda Ro/SS-A autoantibodies in serum samples from Japanese patients with systemic sclerosis (SSc). METHODS: Serum samples from 263 Japanese patients with SSc were examined by double immunodiffusion and enzyme linked immunosorbent assay (ELISA). RESULTS: By double immunodiffusion, 29 serum samples from patients with SSc were found to possess anti-Ro/SS-A antibodies. By ELISA, 31 serum samples were positive for anti-Ro52 and/or anti-Ro60. Of 27 serum samples that were positive by both methods, 15 reacted with both Ro52 and Ro60, five with Ro52 alone, and seven with Ro60 alone. Eleven of 12 patients with both anti-Ro52 and anti-Ro60 and all five patients with anti-Ro52 alone had Sjögren's syndrome, while only one of six patients with anti-Ro60 alone had this disorder. CONCLUSIONS: Anti-Ro52 may be a serological marker for the presence of Sjögren's syndrome in anti-Ro/SS-A-positive patients with SSc.

Antibodies, Antinuclear↗

PubMed1996

[Preclinical and clinical studies on the efficacy of bifonazole in patients with tinea pedis at 10 years after approval. Part 1. Susceptibility to bifonazole of clinical isolates of dermatophytes].

An investigation was carried out to determine whether or not here had been any changes in the susceptibility of clinically isolated strains of Trichophyton metagrophytes and Trichophyton rubrum (both leading causes of tinea) to bifonazole, an imidazole derivative and antifungal for topical use. Susceptibility was measured in 107 strains of these fungi isolated from clinical samples during a study on the treatment of tinea pedis with Mycospor cream in 1995, 42 strains isolated and stored in 1990, and 39 strains isolated and stored prior to development of the drug. The results are as follows: (1) There was no distinct difference in the susceptibility to bifonazole of T. mentagrophytes strains isolated before 1986 and those isolated in 1990 or 1995. (2) T. rubrum strains isolated before 1986 were slightly more susceptible to bifonazole than those isolated in 1995, while the 1990 strains were slightly less susceptible than the 1995 strains, but the difference was not significant. (3) The highest MICs of bifonazole for all the T. mentagrophytes and T. rubrum strains isolated from before 1986 and those in 1995 were relatively low, being 2.5 micrograms/ml and 1.25 micrograms/ml, respectively. These results suggest that no resistance or reduced susceptibility to bifonazole has emerged among clinical isolates of dermatophytes since the development of the drug.

Antifungal Agents↗

PubMed1996

[Fundamental and clinical studies on the efficacy of bifonazole in patients with tinea pedis at 10 years after approval. Part 2. Clinical evaluation].

The usefulness of bifonazole (Mycospor), a topical imidazole antifungal agent approved 10 years ago, was evaluated for the treatment of tinea pedis. Mycospor cream was applied by 141 patients with tinea pedis once daily for 4 233ks, and the clinical efficacy and adverse reactions (as well as any correlations with susceptibility of isolates and the mycological activity of the agent against these isolates) were studied. The results were then compared to those of a previous study. The following results were obtained. 1. Mycological activity Mycological examination results became negative in 63.2% (36/57) of the patients with plantar tinea pedis, in 94.1% (32/34) of those with interdigital tinea pedis, and in 74.7% (68/91) of all tinea pedis patients. 2. Mycological activity and MIC No correlation was found between the MICs of bifonazole against the pathogenic fungi and the rate of eradication on mycological examination. 3. Improvement of symptoms The improvement rates for local symptoms were 82.5% for plantar tinea pedis, 85.7% for interdigital tinea pedis, and 83.7% for all tinea pedis. 4. Clinical efficacy Good clinical efficacies were found in 61.4% of the patients with plantar tinea pedis, in 88.6% of those with interdigital tinea pedis, and in 71.7% of all patients. 5. Safety Regarding adverse reactions, what seemed to be contact dermatitis was reported in 5 out of 127 cases (3.9%). The reaction decreased or disappeared in all cases. 6. Usefulness Mycospor was found to be useful in 64.9% of patients with plantar tinea pedis, in 88.6% of those with interdigital tinea pedis, and in 73.9% of all tinea pedis patients. 7. Comparison with former results The results obtained in the present clinical study were comparable to those obtained in patients with tinea pedis treated in a double-blind comparative study conducted during the development of as a new topical antifungal agent. From the above results, Mycospor cream was confirmed to be still useful, although it has been used widely for the topical treatment of cutaneous mycoses in the past 10 years since its approval.

Adult↗

PubMed1995

Ultrasound measurement of skin thickness in systemic sclerosis.

Sclerotic skin change in systemic sclerosis (SSc) usually accompanies increased skin thickness. In order to quantify the cutaneous changes and to clarify the changes in the 'uninvolved' skin in systemic sclerosis (SSc), we measured the skin thickness on the chest, the forearms and the hands of 79 patients with SSc and 81 healthy controls with a B-mode ultrasound (30 MHz) apparatus. The thickness of the 'uninvolved', as well as the 'involved' skin in patients with SSc was significantly greater than that of healthy controls. Increased skin thickness on the forearms and/or the hands showed a 64.6% sensitivity and a 100% specificity for SSc. These results indicated that the skin which appears to be 'uninvolved' in patients with SSc is already pathologic, as shown by increased thickness. Moreover, measurement of skin thickness may be beneficial in the diagnosis of this disease at an early stage.

Adolescent↗

PubMed1993

A case of systemic sclerosis with anticentromere, antitopoisomerase I, and anti-U1RNP antibodies.

We describe a case of systemic sclerosis (SSc) positive for 3 autoantibodies; anticentromere antibody, antitopoisomerase I antibody, and anti-U1RNP antibody, It is known that coexistence of 2 of these 3 antibodies is rare and the coexistence of these 3 antibodies in serum from a patient with SSc has not been reported. In addition, we examined our stock serum samples from 236 cases with SSc or related disorders for the presence of specific antinuclear antibodies and were unable to find a serum sample containing all 3 antibodies.

Autoantibodies↗

PubMed1992

Direct inactivation of herpes simplex virus type-2 by rat epidermal protein.

Proteins were extracted from corneocytes of skin of 2-day-old rats and fractionated by gel filtration and cation exchange column chromatography. The different protein fractions were tested for direct inactivation of herpes simplex virus infectivity as determined by reduction of plaque formation. The most effective protein fractions against herpes simplex virus were a neutral pH buffer soluble and mol. wts. ranging from 20 K to 30 K. Amino acid composition of the proteins were virtually identical to epidermal histidine-rich proteins. The activity was significantly (P less than 0.001) stronger against type-2 than type-1. The activity was most stable at pH 7.2 and the rate of inhibition increased in a time-dependent manner up to 4 h. The 50% effective dose was estimated as 1.1 micrograms protein/ml.

Amino Acids↗

PubMed1989

Candidacidal activities of proteins partially purified from rat epidermis.

Proteins with approximate molecular weights of greater than 300,000 (EP greater than 300K) and 49,000 (EP 49K) were partially purified from terminally differentiated cells of 2-day-old rat epidermis. They were extracted in 0.34 M sucrose containing 0.01 M citric acid and purified by Sephacryl S-300 chromatography followed by reverse-phase column chromatography. The major constituents of EP greater than 300K and EP 49K were focused around pH 10 to 11 by sucrose gradient isoelectric focusing. Both proteins were effective at inhibiting colony formation of Candida albicans and C. tropicalis, but neither inhibited the growth of C. parapsilosis. The effect was maximum below pH 5.0 and reduced considerably above pH 5.0. The activity of EP greater than 300K on C. albicans TIMM 1623 (group A) was much stronger than that of EP 49K, whereas both proteins similarly inhibited C. albicans TIMM 1604 (group B). Their effects against C. albicans TIMM 1623 were dose dependent and were activated after a longer preincubation time, and NaCl concentration influenced their potency. At a low salt concentration and a 60-min preincubation at pH 4.5, the 50% effective dose for EP greater than 300K was calculated to be 1.7 x 10(-9) M, whereas that for EP 49K was 1.8 x 10(-7) M.

Amino Acids↗

PubMed1988