Biomedical subjects

Takuro Katoh

Publications and source records attributed to Takuro Katoh.

5 recordsLinked to original sources

PubMed2006

Preventive effects of various types of footwear and cleaning methods on dermatophyte adhesion.

Tinea pedis is contagious and typically spreads from infected to non-infected persons. The purpose of this study was to evaluate the efficacy of footwear in preventing tinea pedis adhesion. Using the stamp culture method, we investigated the effectiveness of preventing dermatophyte passage by the wearing of stockings made of nylon, socks made of cotton and tabi (Japanese socks), as well as the effect of removing dermatophytes from these items by washing with soap, cold water and cold water after turning inside-out. For sandals, sneakers and boots, we also investigated the effect of dermatophyte removal by pouring cold water into the footwear, wiping with a wet towel, and pouring boiling water into the footwear. The wearing of socks or tabi was effective in preventing passage of dermatophytes. The stocking material proved to be too thin to prevent passage. On the inner side of socks (the side of the sole), all treatments were effective at removing dermatophytes, but on the outer side of socks (the side touching the surface of the sandals), the treatment of washing in cold water after turning inside-out resulted in significantly more dermatophytes as compared with the other treatments. Pouring cold water, wiping with a wet towel and pouring boiling water were all effective for removing dermatophytes from sandals and sneakers. However, for boots, the treatment of pouring cold water was less effective. To prevent the adhesion of dermatophytes to sandals, wearing socks or tabi was effective, and the treatments of washing socks in cold water after turning inside-out and of pouring cold water into the boots were less effective than the others.

Adult↗

PubMed2006

[Dermatomycosis and environment].

Environments may act as reservoirs for pathogenic fungi, a determinant of the establishment of fungal infection, or an exacerbating factor of disease. In recent years, skin disease caused by geophilic fungi has been decreasing, while case reports of zoonoses from various animals are increasing. Outbreaks of anthropophilic T. tonsurans infection pose a problem to medical mycologists. Tinea pedis is the most common exogenous dermatomycosis in Japan. Although T. rubrum is presumed to be the dominant pathogen of this disease, T. mentagrophytes is detected more frequently from various environments, so far, the reason for this discrepancy has not been fully understood. The latest knowledge about the route of dermatophyte foot infection is as follows: (1) Dermatophyte propagules disseminated from patients may contaminate not only bath-mats but also wood floors, Japanese style mattings, concrete floors, slippers, cushions, etc., and from them adhere to healthy skin. (2) The agar stamping method can easily detect dermatophytes from the skin and the environment. (3) Propagules of T. mentagrophytes can survive for more than three months under certain conditions such as in rubber boots. (4) In order to eliminate dermatophytes gathered in socks and footwear, simple procedures (washing, bathing with hot water, or wiping with a towel) are all effective. (5) Prior application of an antifungal agent promptly eradicates dermatophyte propagules adhering to the skin from the environment. The author also mentioned the possibility of asymptomatic dermatophyte colonization, and the high prevalence of dysgeucia in oral carriers of Candida albicans.

Animals↗

PubMed2005

Culturing dermatophytes rapidly from each toe web by fingertip.

The diagnosis of tinea pedis is usually confirmed by microscopy and culture of skin scrapings. Isolating dermatophytes by fungal culture gives more reliable proof of infection and has the advantage of identifying the causative organisms. Nevertheless, culture examination is complementary to microscopy and is not routinely performed because it is time- and cost-consuming. Herein, we propose a new culturing method, the 'finger-sampling method', for collecting dermatophytes from patients' toe webs using the examiner's fingertip as a sample collection tool. Using this method, four toe webs of a foot can be examined at one time on one culture dish. Every toe web of 50 patients with untreated tinea pedis were examined, and dermatophytes were grown from 83 out of 107 (78%) KOH positive toe webs. The isolation ratio by the finger-sampling method was comparable to that by traditional slant culture of skin scrapings performed by skilled practitioners. Culture results were also positive in 19 out of 53 (36%) diseased but KOH negative toe webs and in 38 (16%) normal toe webs, suggesting the existence of unidentified infection. Additionally, we confirmed the efficacy of this method for detecting dermatophyte attachment on the healthy toe web skin of volunteers who had just been exposed to contaminated areas, i.e. Japanese public baths or a bath mat stepped on by a patient disseminating dermatophyte propagules.

Adolescent↗

PubMed2004

Taste disorders in healthy "carriers" and "non-carriers" of Candida albicans and in patients with candidosis of the tongue.

Impairments in taste perception may be caused by a number of factors, including the presence of Candida albicans in the oral cavity. We attempted to establish whether the presence of Candida albicans on the tongue is a cause of taste disorders by studying taste disorders in patients with candidosis of the tongue and in healthy "carriers" and "non-carriers" of C. albicans. Taste disorders and their severity were objectively assessed by the filter-paper disk method in 18 patients with candidosis of the tongue and in 33 healthy "carriers" and 167 healthy "non-carriers" of C. albicans. The gustatory function was re-tested in 7 patients and 8 "carriers" after treatment with topical anti-mycotic medication to detect any improvement. Patients with candidosis of the tongue and "carriers" of C. albicans demonstrated significantly higher incidences (p<0.001) of taste disorders than did "non-carriers". The mean taste threshold of each of the four individual taste qualities was significantly higher in patients with candidosis than in "non-carriers". The average taste threshold was significantly higher in "carriers" than in "non-carriers". Post-treatment improvement or recovery from taste disorders was obtained in 5 out of 7 patients (71.4%) with candidosis and in 7 out of 8 "carriers" (87.5%) of C. albicans. This study clearly demonstrates that not only overt candidosis of the tongue but also commensal harboring of C. albicans is a cause of taste disorders.

Administration, Topical↗

PubMed2003

[Prevention of dermatophytoses].

Preventive measures against tinea pedis were discussed based on our mycological studies using foot-press method and house dust cultures. 1) Untreated patients with tinea pedis frequently disseminate pathogenic fungi into the environment, but dissemination could be easily controlled by simple application of antifungal agents. 2) A high proportion of dermatophytes disseminated in house dust perished naturally within a month under dry conditions, while under moist conditions they survived several months or more. Therefore, humid areas such as the floor and carpet of a bathroom should be cleaned or washed regularly. 3) Adhesion of dermatophytes onto healthy feet usually happens in public spaces where people enter without shoes. Wearing socks cannot prevent dermatophyte adhesion. Cleaning the feet by wiping with a towel or washing with soap seemed to be an effective prophylactic measure after stepping into such spaces.

Dermatomycoses↗