Search PubMed⌕ Search

Biomedical subjects

K Mishima

Publications and source records attributed to K Mishima.

250 records · Page 14Linked to original sources

Expandable metallic stent treatment for malignant colorectal strictures.

Four patients were treated by placement of an expandable metallic stent (two Gianturco Z-stents, two Ultraflex stents) for malignant colorectal strictures. All four patients were able to defecate after stent placement. Stent migration was recognized in one patient. Two patients suffered from tenesmus after stent placement.

Aged↗

Quantitative histologic study of the sural nerve in Lesch-Nyhan syndrome.

The sural nerve of a 31-year-old man with Lesch-Nyhan syndrome obtained at autopsy was studied histologically. Large, myelinated nerve fibers were reduced in number and no myelinated nerve fibers larger than 5 microns were seen. Diameter distribution of myelinated nerve fibers did not demonstrate a bimodal pattern. The density of myelinated nerve fibers was 5,530/mm2 and was decreased as compared to the controls. On electron microscopic examination, lipid-like inclusions were observed in the cytoplasm of some Schwann cells. The role of these inclusions could not be elucidated, but reduction of larger myelinated nerve fibers suggests a peripheral nervous disorder in patients with this syndrome; therefore, patients with Lesch-Nyhan syndrome must be reappraised for disorders of the peripheral nervous system.

Adult↗

Different manifestations of circadian rhythms in senile dementia of Alzheimer's type and multi-infarct dementia.

Using an actigraph and a long-term body temperature (BT) monitoring system, we simultaneously monitored rest-activity (R-A) and BT rhythms in patients with senile dementia of Alzheimer's type (SDAT; n = 20) or multi-infarct dementia (MID; n = 21) for 5-7 consecutive days. The SDAT group exhibited a well-organized BT rhythm with significantly higher amplitude compared with the MID group. The SDAT group also showed significant positive correlation between the total daily activity as well as percentage of nighttime activity and the degree of dementia, while no such tendency was observed in the MID group. The different properties of the biological rhythm disorders among the SDAT and MID groups possibly underlie their sleep and behavioral disorders.

Aged↗

Hypothermic action of exogenously administered melatonin is dose-dependent in humans.

The pineal hormone melatonin (MLT) is closely related to sleep initiation and maintenance in humans, and is now used as a potent therapeutic tool for some circadian rhythm sleep disorders. Acute and transient hypothermia induced by exogenously administered MLT (ex-MLT) may play a critical role in the circadian phase shifting and hypnogenic actions. Six healthy young male volunteers (mean age, 22.5 y; age range, 19-24 y), whose endogenous MLT secretion rhythms were previously assessed, took either 0.5 mg, 3 mg, or 9 mg of ex-MLT or a placebo at 0930 h (the average sleep onset time was 0000 h) on a randomized, single-blind, crossover basis. In comparison with placebo, ex-MLT significantly suppressed core body temperature at the 3-mg and 9-mg doses and slightly suppressed core body temperature at the 0.5-mg dose. There was significant positive correlation between the magnitude of core body temperature suppression and the area under the MLT concentration curve as well as the peak MLT concentration after ex-MLT administration. Our study showed that clinical doses of ex-MLT induce hypothermia in a dose-dependent manner. Results suggest that the therapeutic effect of larger doses of ex-MLT should be tested on patients who benefit little from typically lower clinical doses of ex-MLT.

Adult↗

Presence of defensin in epithelial Langerhans cells adjacent to oral carcinomas and precancerous lesions.

We aimed to immunohistochemically study the localization of defensin (HNPs), a family of peptides with antimicrobial and cytotoxic activity, in oral tumor tissue. Therefore, tissue sections were embedded in paraffin, and defensin was immunostained by the streptavidin-biotin coupled peroxidase method. Langerhans cells were confirmed by indirect immunostaining with anti-S-100 protein polyclonal antibody. Melanocytes were stained with Fontana-Masson's stain. Neutrophils and intimal cells were stained by anti-defensin antibody. Langerhans cells in normal epithelium or dysplasic epithelium adjacent to squamous cell carcinoma and precancerous lesion were also stained. Defensins (HNPs) are nonspecific peptides that occur in neutrophils and protect against bacteria, fungi, and tumor cells. Since defensins are also found in epithelial Langerhans cells adjacent to tumor tissue, these peptides most likely have a role in tumor immunity.

Defensins↗

Defensin-1, a peptide detected in the saliva of oral squamous cell carcinoma patients.

The saliva of patients with oral squamous cell carcinoma was subjected to reversed-phase HPLC, and a peak (P 14) was eluted with a linear gradient of acetonitrile. The molecular weight of P14 was 3,442 daltons by mass spectrometry. The results of amino acid sequencing by Edman degradation and homology studies indicated that P14 was consistent with a peptide, human alpha-defensin 1 (HNP-1) which belongs to the defensin family. The concentration of HNP-1 in the saliva of 6 squamous cell carcinoma patients before surgery and 11 after surgery was 12.3 +/- 8.6 and 6.5 +/- 5.9 micrograms/ml (mean +/- S.D.), respectively. In contrast, minimal amounts of HNP-1 were found in the saliva of adenocarcinoma patients and healthy volunteers. The concentration of salivary HNP-1 correlated positively with serum squamous cell carcinoma related antigen (SCC-Ag)level (r = 0.879, p < 0.01).

Adult↗