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Biomedical subjects

T Hamada

Publications and source records attributed to T Hamada.

At least 523 records · Page 29Linked to original sources

Detection of ornithine decarboxylase gene expression in 12-O-tetradecanoylphorbol-13-acetate-treated mouse skin using in situ hybridization.

The localization of ornithine decarboxylase gene expression in mouse skin by tumour promoter, 12-O-tetradecanoylphorbol-13-acetate, was investigated using in situ hybridization. After 4 h of treatment with tumour promoter, the grains representing ornithine decarboxylase mRNA increased remarkably in number in the epidermis, especially in the follicular region. When the cells containing more than 5 grains were counted as positive, the number of positive cells increased by about 52-fold in the follicular epidermis, by about 19-fold in the interfollicular epidermis and by 4-fold in the dermis, as compared with controls. These results indicate that the epidermal cells are mainly responsible for the activation of ornithine decarboxylase by 12-O-tetradecanoylphorbol-13-acetate.

Animals↗

Effect of retinoic acid on the infiltration of murine melanoma cells into the type I collagen gel.

Two lines of murine melanoma cells (B16 and Cloudman S91) were cultured on type I collagen gel and the effects of all-trans-retinoic acid on the growth and infiltration into the gel were assayed. In both lines, proliferation and the degree of infiltration were suppressed by the addition of all-trans-retinoic acid. The infiltration-inhibiting effect was expressed very rapidly and was dose-dependent at concentrations ranging from 10(-7) to 10(-5) M of all-trans-retinoic acid. These results suggest the anti-invasive effects of all-trans-retinoic acid on melanoma cells.

Animals↗

A case of prurigo pigmentosa considered to be contact allergy to chromium in an acupuncture needle.

A 53-year-old male developed prurigo pigmentosa on his back, after undergoing acupuncture for 3 years. The eruptions were ceased on discontinuing the therapy but recurred with its resumption. The acupuncture needle contained 18.12% chromium. Erythema was induced by patch testing with potassium dichromate, and a flare-up was observed in the area of the patch test on resumption of acupuncture. We consider that the eruptions were induced by contact allergy to the chromium component of the acupuncture needles.

Acupuncture Therapy↗

Crusted scabies in acquired selective IgA deficiency.

Crusted scabies, an unusual clinical variant of human scabies mite infestation, is usually reported in cases of gross debility, mental deficiency, or immunosuppression. We report here the occurrence of crusted scabies in a 40-year-old man with acquired selective IgA deficiency suspected to be caused by long-term medication with phenytoin for epilepsy.

Adult↗

Effect of PUVA radiation on anaphylactic histamine release from rat dermal tissues.

We have devised a new in vitro model of type I cutaneous anaphylaxis. Male albino rats were sensitized with DNP-Ascaris. Abdominal skin was shaved, and thin, split-thickness slices of skin were cut with a dermatome. The dermis was excised and cut into 100 mg pieces. The dermal tissue was incubated with antigen in Tyrode's solution for 30 min at 37 degrees C. Antigen-induced histamine release from dermal tissue was measured fluorimetrically. Using this system, we measured histamine release from PUVA-irradiated and non-irradiated dermal tissues. A single PUVA irradiation inhibited type I cutaneous anaphylaxis, but did not affect spontaneous histamine release or total dermal histamine. Our model is considered to be useful for investigation of the mechanism of suppression of type I cutaneous anaphylaxis by PUVA.

Anaphylaxis↗

[A case of recurrent cranial neuropathy presenting as recurrent Tolosa-Hunt syndrome].

A 64-year-old woman, with history of hypertension and arteriosclerosis, developed left painful ophthalmoplegia in July, 1988. Neurological examination proved abnormality of the third cranial nerve innervation, otherwise normal. No systemic illness was present. With corticosteroid therapy, the symptoms regressed and completely disappeared in 3 months. In January, 1990, right painful ophthalmoplegia appeared. Neurological examination revealed involvement of right sixth nerve and first branch of the right fifth nerve. With corticosteroid therapy, the symptoms completely regressed in several weeks. In April, 1990, she developed severe pain in the right side of the face. The facial pain disappeared rapidly with corticosteroid therapy, but reappeared following quit of steroid. She complained of severe pain of the right face, the territory of first and second branch of the right fifth nerve, but neurological examination was negative. With corticosteroid therapy, the pain disappeared remaining with mild tingling sensation on the right face, but during the tapering of corticosteroid in August, a severe peripheral type right facial palsy developed. Corticosteroid therapy resumed and the facial palsy regressed almost completely in ten days. Our case suggests that THS might be a variant of so-called recurrent cranial neuropathy.

Aged↗

[Clinical study of gene locus heterogeneity in hereditary olivopontocerebellar atrophy (OPCA)--report of 2 pedigrees affected with non SCA1 type OPCA].

From the linkage study of D6S89, we previously reported that hereditary OPCA in Japan is genetically heterogenous. Two pedigrees, P2 and P35, reported in this report, were not linked to D6S89. In order to examine possible correlation between OPCA genotypes and disease phenotypes, we studied clinically eight cases in these two pedigrees. One autopsied case in pedigree P2 was proven to have marked neuronal degeneration in the inferior olivary nuclei, pontine nuclei, cerebellar cortex, and substantia nigra. Dentate nucleus and oculomotor nuclei were free from neuronal degeneration. Clinical features of those 8 patients were fairly uniform, characterized by cerebellar ataxia, hypoactive DTR, and slow eye movement. Parkinsonism or choreiform movements were observed in one patient, respectively. Pupillary dilatation, twitching of face and tongue, limb amyotrophy were observed in patients of advanced stages. However, these signs were not dominating nor common throughout clinical course. None of our cases showed hyperactive DTR, limb spasticity, or external ophthalmoparesis. On the other hand, these latter signs were popular in SCA1 so far as reviewing the literature. The present study showed that there was possible correlation between genotypes and phenotypes in hereditary OPCA.

Adult↗

[Radionuclide cavography before and after percutaneous transluminal angioplasty in Budd-Chiari web: case report].

A case of the Budd-Chiari syndrome due to a web of the hepatic inferior vena cava (IVC) is reported. A 54-year-old male with mild liver dysfunction was suspected with IVC obstruction from the screening CT which revealed liver cirrhosis with marked caudate lobe enlargement and dilatation of azygous and hemiazygous vein. Subsequent radionuclide cavography with 99mTc-HSA clearly demonstrated IVC obstruction, but failed to clarify the site or type of the obstruction. Finally contrast cavography diagnosed a web of the hepatic IVC, which was treated by percutaneous transluminal angioplasty (PTA). During two-year follow-up after PTA none of the radionuclide cavographies showed reocclusion of the IVC and as a result contrast cavography was avoided. Radionuclide cavography, therefore, was a useful method for evaluating IVC obstruction before and after PTA for the Budd-Chiari web.

Angioplasty, Balloon, Coronary↗

[A case of pathological dilation of seminal vesicle with high level of serum CA-19-9].

A case of pathological dilation of seminal vesicle is presented. A 18-year-old male was admitted to our hospital with the complaints of gross hematuria and discomfort of the scrotum. IVP and abdominal CT scan revealed the left aplastic kidney, and ultrasound, vesiculography, and pelvic CT scan revealed markedly dilated bilateral seminal vesicles without filling defects. The level of serum CA19-9 was 390 u/ml, which was extremely high. After resection of dilated seminal vesicles, it returned to the normal range (37 u/ml). Sixty six cases of pathological dilation of seminal vesicle were collected from the Japanese literature. No cases showing a high level of serum CA19-9 have been reported in Japan.

Adolescent↗

[A study on BrdU labelling index of gastric cancer using in vitro labelling method].

In order to reveal the effect of environmental factors to BromodeoxyUridine labelling index (BrdU L.I.) and its usefulness as clinicopathological information, 522 specimens obtained from 121 lesions of gastric cancer were studied. Five hundred twenty two specimens in which BrdU had been incorporated using an in vitro labelling method were divided into 3 groups according to their degree of necrosis and cell infiltration. The average L.I. of the specimens with no or slight necrosis was 23.3 +/- 8.7%, medium, 14.2 +/- 10.0%, and severe necrosis, 6.6 +/- 3.8%, with no or slight cell infiltration, 25.3 +/- 9.5%, medium, 21.0 +/- 7.1%, and severe cell infiltration, 21.2 +/- 6.1%, therefore L.I. correlated to necrosis and cell infiltration. Representative values for each lesion were adopted and compared using 3 methods. In method A, a representative value of the L.I. for each lesion was chosen using all biopsy specimens, method B using specimens without necrosis, and method C, specimens without necrosis and cell infiltration. L.I. correlated to stage and the lymphnode metastasis only using methods, B and C and more strictly using method C. Necrosis and cell infiltration should be considered in adopting a representative value of the L.I. for each lesion. Method C is considered to be a best among the three studied, and the L.I. of gastric cancer may be considered a clinicopathological marker.

Biopsy↗

[MR imaging of optic neuritis using short T1 IR (inversion recovery)].

We evaluated the ability of MRI using short T1 inversion recovery (STIR) to diagnose optic neuritis. Eleven patients with previous or recent attack of optic neuritis were studied with MRI at 0.5 tesla. STIR images revealed high signal regions in 7 of 12 symptomatic and 5 of 10 asymptomatic nerves. Three of five asymptomatic nerves with high intensity were pertinent to the cases with past attack and seemed to reflect the demyelinating change. The other two nerves were pertinent to the cases without past attack and seemed to show occult lesions. We consider that STIR is useful in detection of optic nerve lesions associated with optic neuritis.

Humans↗

[Scrotal scintigraphy in the diagnosis and grading of varicocele].

Scrotal scintigraphy with 99mTc-red blood cells has been reported as a useful method for detecting varicocele. In this study we analysed the scintigraphy of 251 infertile males with clinically diagnosed or suspected varicocele, in an attempt to establish a grading system of varicocele. Scintigraphically varicocele was diagnosed in 207 patients on the basis of pooling in hemiscrotum in static images and/or early flow through the spermatic cord vessels in dynamic images; physical examination overlooked 17 of them. Of the 207 patients, all had pooling (153 left-sided, 1 right-sided, and 53 bilateral pooling) and 52 had early flow. The early flow was a less sensitive sign for varicocele than the pooling and invariably accompanied by the intense pooling. The early flow may be related to increased shunt flow through varicocele. According to the scintigraphic findings, varicocele was classified as follows: Grade I (small varicocele with faint early flow or mild localized pooling, n = 103), Grade II (medium varicocele with obvious early flow or curvilinear mottled pooling, n = 67) and Grade III (large varicocele with marked early flow or pooling, n = 37). Clinical assessment (93 small, 68 medium, and 54 large varicocele) supported the scintigraphic classification. Scrotal scintigraphy, therefore, facilitates precise evaluation of varicocele based on its morphology and hemodynamics.

Adult↗

Multiple primary cancers in a case of chronic arsenic poisoning--an autopsy report.

This is an autopsy report of multiple primary cancers observed in a patient who had clinically been diagnosed as chronic arsenic poisoning. An 88-year-old man, non-smoker, had worked in an arsenic mine for 6 years from the age of 47. He had undergone operations for Bowen's disease and gastric cancer at ages 80 and 86, respectively. At autopsy, squamous cell carcinoma of the lung and a polypoid lesion in the piriform recess were found. Furthermore, microscopic examination revealed latent prostatic adenocarcinoma and oncocytoma in the kidney. The polypoid lesion of the piriform recess appeared to originate from the duct of the minor salivary gland in the pharynx, showing an adenoid cystic carcinoma-like pattern with squamous cell carcinoma in part. The cause of death was thought to be respiratory failure due to bronchopneumonia and pulmonary edema as well as hydrothorax, and chronic heart failure following ischemic heart disease. Bowen's disease was followed by four internal malignant tumors, even though the etiological relation between these cancers and arsenic is not clear.

Adenocarcinoma↗

Cell cycle analysis of human dermal fibroblasts cultured on or in hydrated type I collagen lattices.

The proliferation and cell cycle phase composition of human dermal fibroblasts cultured on or in type I collagen lattices (reconstituted dermis model) were examined. On collagen lattices, as compared with conventional cultures on plastic dishes, the proliferation of human dermal fibroblasts was suppressed, being arrested at about one-half the saturation density after 10 days of culture. In collagen lattices, proliferation was further suppressed, being nearly arrested within 4-7 days of culture. Cells were analyzed for cell cycle phases by two-color flow cytometry using DNA staining and S phase cell staining with FITC-conjugated antibromodeoxyuridine antibody. After 5 days of culture, the number of S phase cells on collagen lattices was 49.3% of that on plastic dishes, with an increase in G0G1 phase cells of 79.8%. In collagen lattices, the number of S phase cells was very small (4.3% of all cells), and most of the cells accumulated in G0G1 phase. These findings suggest that the cell cycle of fibroblasts is arrested at G0G1 phase by their interaction with collagen. On the basis of these results, the reconstituted dermis model using collagen lattice is considered to be analogous to the dermis in vivo with respect to cell growth and cell cycle phase composition.

Cell Cycle↗

Enhanced melanogenesis of murine melanoma cells cultured on or in collagen gel.

To elucidate the interaction between melanoma and its matrix, we cultured B16 murine melanoma cells on and in type I collagen gel and evaluated specified functions of melanoma cells; tyrosinase activity and melanin-synthesizing capacity. Proliferation of cells cultured in these environments was markedly suppressed compared with that of cells cultured conventionally on plastic. On the other hand, the tyrosinase activity of cells cultured in or on collagen gel was two to three times higher than that of cells cultured on the plastics, while their melanin production was approximately double that achieved during conventional culture of cells. In conclusion, collagen gel influenced the growth and cell-specific functions of the melanoma cell. The culture system using collagen gel as substrate may be useful for the investigation of the interaction between melanoma and its matrix.

Animals↗