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Biomedical subjects

J Jidoi

Publications and source records attributed to J Jidoi.

At least 37 records · Page 2Linked to original sources
PubMed1993

Spectrophotometric study of alpha-adrenoceptors affecting microcirculation of rat skin.

1. To determine the alpha-adrenergic receptor subtypes that affect the microcirculation of skin, the relative absorption (RA) spectra of the skin on the backs of rats were measured using reflectance spectrophotometric methods. We injected alpha-adrenergic agonists, noradrenaline (NA), phenylephrine (PE) and clonidine (CL), intravenously and determined changes in the RA value at 569 nm, one of the isosbestic points of the oxyhaemoglobin and deoxyhaemoglobin absorption. 2. NA reduced the RA value and the reduction was inhibited significantly by pretreatment with phenoxybenzamine (PBZ; P < 0.01). These findings suggested that the haemoglobin content in the skin tissue decreased as a result of vasoconstriction through alpha-adrenoceptors. 3. NA, PE and CL produced dose-dependent reductions in RA. CL and NA produced virtually equipotent reductions except at the highest dose used. PE produced smaller effects. The potency of these drugs in terms of changes in RA did not correlate with their potency in terms of rises in systemic blood pressure (NA > PE > or = CL). 4. Yohimbine (YO) inhibited the NA-induced reduction in RA to a greater degree than bunazosin (BU). Midaglizole, a specific alpha 2-adrenergic antagonist, significantly and dose dependently inhibited the NA-induced reduction in RA. 5. Although BU inhibited NA-induced reduction in RA only slightly, the effect was significant (P < 0.05). BU significantly inhibited PE-induced reduction (P < 0.01), but did not inhibit CL-induced reduction. 6. These observations suggest that the microcirculation of the skin of the rat is affected mainly by alpha 2-adrenoceptor mediated vasoconstriction. However, alpha 1-adrenoceptor mediated vasoconstriction also has some effect.

Adrenergic alpha-Agonists↗
PubMed1992

Real-time measurement of microcirculation of skin by reflectance spectrophotometry.

A reflectance spectrophotometric measurement was developed to analyze the microcirculation of the skin in real time. The relative absorption (RA) spectra were obtained from skin tissue 10 times per second using a spectro-multi-channel-photodetector system. In this system, white light was projected onto the skin of the back of the anesthetized rat and the spectrum of the reflected light between 450 and 643 nm was analyzed. Two absorption peaks at wavelengths of about 540 and 577 nm were observed, corresponding to the absorption peaks in the oxyhemoglobin (HbO2) spectrum. Either phlebotomy or the i.v. injection of norepinephrine (NE) reduced the RA spectrum. Peaks of the reduction in spectrum [(RA spectrum before the treatment) - (RA spectrum after the treatment)] were observed at about 540 and 577 nm. Injection of NE (0.75-48 ng/100 g B.W., i.v.) reduced the RA value at 577 nm dose-dependently, suggesting a decrease in the skin blood flow due to vasoconstriction. In addition, the content of HbO2 and capillary permeation were measured at the same time after the i.v. injection of Evans blue (EB) dye. As indices of HbO2 content and capillary permeation, RA changes at 540 and 610 nm (the latter is an absorption peak in the EB spectrum) were measured in real time, respectively. Both RA values increased dose-dependently after the intradermal injection of histamine (0.3-100 micrograms/site), suggesting the presence of vasodilation and an increase in permeability. The time at which the RA value for HbO2 reached a maximum was shorter than that for EB. These observations suggest that the method described here can detect changes in the HbO2 content and permeation of skin microcirculation at the same time, and in real time.

Animals↗
PubMed1992

Some biochemical characteristics of a partially purified extracellular keratinase from Trichophyton schoenleinii.

A Trichophyton schoenleinii (T. schoenleinii) strain from tinea favus was cultured in a liquid medium, from which an extracellular keratinase extract was obtained. The keratinase was partially purified with carboxymethyl-cellulose (CMC) column chromatography. Some biochemical characteristics of the keratinase were then examined. Its molecular weight was estimated to be 38,000 on sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The optimal temperature was 50 degrees C, and the optimal pH value was 5.5. The keratinolytic activity was specifically increased by Fe++ and Fe .

Animals↗
PubMed1991

Lupus miliaris disseminatus faciei--report of a case in an elderly woman.

A 71-year-old Japanese woman developed red-brown to yellow papules symmetrically on the eyelids and cheeks. The histopathology of a papule showed caseation necrosis surrounded by epitheloid cells intermingled with giant cells in the dermis. The patient was thus diagnosed as lupus miliaris disseminatus faciei (LMDF). To the best of our knowledge, no LMDF patients of such an age have been described previously.

Aged↗
PubMed1990

Amounts of fibrous proteins and matrix substances in hairs of different races.

Fibrous proteins (FPs) and matrix substances (MSs) were extracted as S-carboxymethylated (SCM) derivatives from scalp hair of five individuals each of the Mongoloid, Negroid and Caucasoid races. The ratio of the extracted SCM FPs to SCM MSs in dry weight was calculated for each hair specimen. The ratios obtained from the Mongoloid hair were 0.45 +/- 0.03; those from the Negroid, 0.18 +/- 0.02; and those from the Caucasoid, 0.29 +/- 0.02. It has thus been suggested that the ratios of FP to MS contents in the hair may be involved in the determination of the macroscopic racial variations in the form of hair.

Hair↗
PubMed1990

A familial occurrence of sporotrichosis.

A grandfather and granddaughter suffering from sporotrichosis were reported. It is thought that they might have been infected from the same source of Sporothrix schenckii (S. schenckii).

Aged↗
PubMed1990

Two-dimensional polyacrylamide gel electrophoresis of human hair matrix proteins using isoelectric focusing electrophoresis as the first dimension.

S-carboxymethylated (SCM) matrix proteins from fifteen normal human scalp hair specimens were analyzed using two-dimensional polyacrylamide gel electrophoresis (PAGE) with usual isoelectric focusing electrophoresis as the first dimension and then with usual sodium dodecyl sulfate-PAGE as the second dimension. On the electrophoregrams obtained, one low-mobility smear of SCM proteins embedding one SCM protein band was always seen. Many higher-mobility SCM protein spots were also always seen. However, some variations were seen in these SCM protein compositions; in type I, there were eighteen SCM protein components and, in type II, seventeen components.

Adult↗
PubMed1990

Proliferating trichilemmal tumor with apocrine sweat glands.

A 43-year-old man with a proliferating trichilemmal tumor is described. Since the tumor had appeared on a pre-existing alopecia and accompanied ectopic apocrine sweat glands, it is supposed that the pathogenesis of the tumor of our patient might be similar to that of an organoid nevus.

Adult↗
PubMed1990

[A case of cutaneous localized cryptococcosis].

A 65-year-old Japanese male with cutaneous localized cryptococcosis, which was developed as an erythematous infiltrated plaque on the right side of the face, was reported. The biopsy specimen taken from the lesion showed a granulomatous change with many spores in the dermis. Culture of the biopsy specimen gave Cryptococcus neoformans serotype D. There were no cryptococcal infections in the other organs. The skin lesion was improved by a systemic administration of miconazole. This patient was unusual since the cryptococcal lesion was limited to the skin, nevertheless he was under a severe cellular immunity deficiency. The reason for this may be that the infected C. neoformans strain belonged to serotype D.

Aged↗
PubMed1989

A case of tick-bite from Ixodes ovatus Neumann--a report from west Japan.

A 70-year-old male forestation worker had a tick-bite on the lower abdominal skin. The bite was treated by surgical excision of the tick together with the surrounding skin. The tick was identified as Ixodes ovatus Neumann through investigation of its morphological characteristics. This patient is the fourth case of a tick-bite from Ixodes ovatus Neumann in western Japan.

Aged↗
PubMed1989

A case of mosquito hypersensitivity showing abnormality of peripheral monocyte function.

We report here an 11-year-old, Japanese girl with an ulcer-forming type of mosquito hypersensitivity. Since the lesions might have arisen from an Arthus type of hypersensitivity, we used a phorbol myristate acetate (PMA)-triggered chemiluminescence method to investigate the function of her peripheral monocytes, which should play an important role in any Arthus reaction in association with polymorphonuclear leucocytes (PMNs). The chemiluminescence of the patient's monocytes was significantly reduced from that of the normal control. To our best knowledge, no such functional abnormality of the monocytes has been seen previously in patients with an ulcer-forming type of mosquito hypersensitivity.

Animals↗
PubMed1989

Comparison of human hair and nail low-sulfur protein compositions on two-dimensional electrophoresis.

Compositions of human normal hair and nail low-sulfur proteins were compared using two-dimensional electrophoresis of their S-carboxymethylated (SCM) derivatives. Six SCM low-sulfur protein components with molecular weights (MWs) of 76,000, 73,000, 72,000, 64,000, 61,000 and 55,000 were common to the hair and nail. One component with a MW of 61,000 was specific to hair, and two components, both with a MW of 50,000, were specific to nail.

Adult↗