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T Doi

Publications and source records attributed to T Doi.

At least 397 records · Page 22Linked to original sources
PubMed1989

Effect of vitamin B12-deficiency on the activity of hepatic cystathionine beta-synthase in rats.

The effect of vitamin B12(B12)-deficiency on the activities of hepatic methionine synthase, homocysteine methyltransferase, and cystathionine beta-synthase was investigated in rats. The rats bred from B12-deficient dams were fed the B12-deficient diets for 150 days after weaning. Growth retardation of the B12-deficient rats was already observed on day 30 and continued through 150 days. But dietary supplementation of 0.5% DL-methionine slightly improved the growth retardation. Urinary excretion of methylmalonic acid increased to about 15 mg/mg creatinine and hepatic B12 concentration declined to about 2 ng/g liver after a 150-day feeding of the B12-deficient diets. Hepatic methionine synthase activity in rats fed the B12-deficient diets supplemented with or without methionine decreased to about 5% of B12-supplemented controls. Hepatic betaine-homocysteine methyltransferase activity showed no significant change caused by B12-deficiency. Hepatic cystathionine beta-synthase activity in rats fed the B12-deficient diets supplemented with or without methionine decreased to about 61% and 27% of their B12-supplemented controls, respectively, but the decrease was partially improved by methionine supplementation. In conclusion, the rats bred from B12-deficient dams showed a severe B12-deficiency after a 150-day feeding of the B12-deficient diets. The decrease of hepatic cystathionine beta-synthase activity was supposed to be due to the adaptation by the defect of methionine resynthesis.

5-Methyltetrahydrofolate-Homocysteine S-Methyltran↗
PubMed1989

Insulinlike growth factor-1 is a progression factor for human mesangial cells.

Mesangial cell hyperplasia is a feature common to several human glomerular diseases. The cause of this increased cell number is unknown. The authors assessed human mesangial cells in vitro and found that they possessed an insulinlike growth factor-1 (IGF-1) receptor consisting of alpha and beta units (Mr, 130 k and 90 k respectively). Fifty percent inhibition of IGF-1 specific binding to the receptor required 1 X 10(-9) M IGF-1, greater than 1 X 10(-6) M insulin and 1 X 10(-7) M multiplication stimulating activity (MSA). Analysis of binding by the method of Scatchard revealed one type of IGF-1 receptor with a Kd of 1.35 X 10(-9) M, and a number per cell of 1.04 X 10(5). Binding studies on whole glomeruli had similar specificity and there were 7.17 X 10(7) receptors per glomerulus (Kd, 1.12 X 10(-9) M). Examination of the effect of IGF-1 on the cell cycle revealed that exposure of cells to both IGF-1 and platelet-derived growth factor (PDGF) led to a significant increase in 3H-thymidine incorporation into cell layers. Antibody to PDGF abolished only that response due to PDGF. Similarly, the labeling index of cells pretreated with PDGF, washed, and then exposed to IGF-1 was increased, whereas if the order of ligand exposure was reversed, there was no such additive effect. Finally, PDGF increased RNA and protein synthesis, and this response was not enhanced by IGF-1. In summary, human mesangial cells and whole glomeruli possess IGF-1-specific receptors and IGF-1 was found to act as a progression factor in the cell cycle.

Cells, Cultured↗
PubMed1989

[A case report of multiple intracranial tuberculoma associated with miliary tuberculosis and review of the literature].

We reported a case of multiple intracranial tuberculoma associated with miliary tuberculosis and reviewed the cases reported as intracranial tuberculoma in the past 11 years. A 41-year-old diabetic man was admitted to our hospital for the treatment of miliary tuberculosis and respiratory insufficiency. On admissIon, he had no neurological deficits except mild consciousness disturbance due to respiratory failure. He developed headache and mental confusion three weeks after the beginning of antituberculous therapy with isoniazid, streptomycin, rifampicin, and ethambutol. Neurological examination revealed that he had progressive right hemiparesis and was in a confusional state. Enhanced CT showed multiple intracranial nodular lesions. During 6 weeks, he had progressive neurological manifestations in spite of his initial antituberculous treatment. He responded well, however, to the chemotherapy with combination of isoniazid, kanamycin, pyrazinamide and ethionamide that were sensitive to tuberculous bacilli separated from his sputum. He became minimally right-hemiparetic by 6 weeks after the change of antituberculous medication. Serial enhanced CT scan proved to be of great value in the diagnosis and follow-up study of intracranial tuberculoma. From 1978 to 1988, there were 72 reported cases of intracranial tuberculoma in Japan; 37 were male, 32 were female and 3 were uncertain because of no detailed document. The age of onset was distributed from 6 month to 81 years in age and 2 peaks were seen in the second decade and fifth to seventh decade. Thirty-three (48%) out of 69 cases had multiple intracranial lesions. A few reports commented that neurological complications tended to appear even if they were under antituberculous therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1989

Autoimmune abnormalities in a murine model of accelerated senescence.

Immunopathological abnormalities in senescence-accelerated mice (SAM) were studied by comparison of senescence-prone (SAM-P/1) and senescence-resistant (SAM-R/1) mice. Sera from SAM-P/1 mice contained a number of autoantibodies, including natural thymocytotoxic autoantibody (NTA), anti-nuclear antibodies (ANA) and IgG anti-single-stranded and anti-double-stranded (ss and ds) DNA antibodies. Furthermore, an earlier increase in serum IgG2 levels and an earlier appearance of IgG circulating immune-complexes (CIC) associated with low C3 levels, were observed in SAM-P/1 mice. These serological findings were distinctive features in SAM-P/1 mice, which could almost discriminate these mice from SAM-R/1 mice. In addition, age-associated glomerular mesangial and capillary lesions with granular IgG and C3 deposition were frequently observed in SAM-P/1 mice, whereas SAM-R/1 mice even at 10 months of age showed only mild mesangial lesions. These findings suggest that autoimmune abnormalities may contribute to the accelerated senescence in these mice.

Aging↗
PubMed1989

[A case of gastric carcinoid with transient features of tubular adenocarcinoma].

A 51-year-old male sought a medical advice because of gastric lesion that had been detected by a mass screening though the man felt no symptoms. Gastrofiberscopy revealed a superficially elevated, depressed lesion on the lesser curvature of the antrum. Biopsy specimens showed a moderately differentiated adenocarcinoma, and surgically obtained material, about 1.5 cm in diameter, revealed a carcinoid and tubular adenocarcinoma. The tumor consisted mainly of carcinoid tissue while the surface of the tumor manifested, histologically, an adenocarcinoma, though the margins of the two histologies were unclear. The carcinoid tissue revealed a positive Grimerius-staining and a negative Fontana-Silver staining. Fifteen patients having a gastric lesion containing a carcinoid and a carcinoma have been reported in Japan. Five of these 15 cases were pointed out as having existing transient features between the cancer and carcinoid.

Adenocarcinoma↗
PubMed1989

The contribution of glomerular mesangial cells to progressive glomerulosclerosis.

These data from in vitro studies, partially confirmed on intact glomeruli, suggest that glomerular cells are not only responsive to a number of growth-regulatory peptides but they are also important sources of several of these agents. The studies on transgenic mice confirm the potential role of the insulin-like peptides. This model also provides clear evidence that genetically directed modifications of cell behavior are important in the pathogenesis of glomerulosclerosis. The ability of glomerular cells to undergo proliferation and participate in hypertrophy of the glomerulus may be a critical determinant in the development of progressive glomerulosclerosis. That this ability is controlled by genetic differences between species and individuals seems well-established in both animal studies and clinical experience.

Animals↗
PubMed1989

[Telling the patient the diagnosis of cancer].

Four cases are presented for discussion. In the first case, the patient believed the doctor for a while when his suspicion of cancer was forcibly denied. But when radiotherapy followed the operation, he became convinced that he had been deceived and confronted the doctor aggressively to force him into a confession. In the second case, the patient, a resident of the U.S. for many years, was told on completion of tests the true diagnosis even before his American wife learned of it. He became very depressed, while his wife kept urging him to fight the cancer. In the third case, the doctor thought better of the earlier decision by another doctor not to tell the truth. The doctor called the patient's relatives to discuss the advisability of telling the truth and when he secured their confidence, he visited the patient with them and told him the true diagnosis. The patient recovered from the initial shock and lived peacefully for several months enjoying the new union he felt with his wife. In the fourth case, it is as if there were a kind of silent conspiracy between the doctor and the patient's relatives who kept her in the dark about her condition. When her illness went downhill, she became completely withdrawn, though she accepted religious ministering to the end. It is cruel to deceive the patient with false hopes. But to tell the patient the truth needs tact. The doctor in the third case gives a very good model of it. First, he assesses the patient's personality. Second, he convinces the patient's relatives of the advisability of truth-telling. Third, he assures the patient that he is in charge no matter what happens to him. Perhaps it was easier to tell the patient the diagnosis of cancer or its poor prognosis in bygone days than nowadays, when the wonders of modern medicine are too much publicized.

Humans↗
PubMed1989

The role of culture and family in mental illness.

A case is presented of a 25-year-old Oriental man who shocked his family by revealing his homosexuality, choosing atheism over his family's traditional Christian religion, and attempting suicide. The discussant examines the cultural implications of the family's reactions to the patient's clinical picture.

Adult↗
PubMed1988

Multivariate analysis for histologic prognostic factors in soft tissue sarcomas.

To investigate histologic prognostic factors in soft tissue sarcomas (STS), multivariate analysis was performed on 236 patients with complete clinical information. These included 141 males and 95 females with an age range from 1 to 85 years (median, 47.6 years). Histologically, malignant fibrous histiocytoma (33.5%) was the most common type followed by synovial sarcoma (11%), liposarcoma (10%), rhabdomyosarcoma (7%), and leiomyosarcoma (7%). Monofactorial analysis revealed that sex, depth, location, histologic grade, cellularity, frequency of mitosis, and necrosis were significant prognostic factors. By multivariate analysis, only frequency of mitosis and depth of tumors were proved to be of prognostic significance. The prognostic importance of the frequency of mitosis as shown in previous and the present studies indicates that further investigation of the cell proliferation in patients with STS is required.

Age Factors↗
PubMed1988

Ossification of the ligamentum flavum. A case report and its MRI finding.

A case of thoracic myelopathy due to ossification of the ligamentum flavum is presented. A fifty-five year old female complained of sensory and motor disturbance of lower limbs. Neuroradiologically, in addition to ossification of the posterior longitudinal ligament throughout the spines, ossified ligamenta flava were found at the Th10-11 level and magnetic resonance imaging (MRI) clearly showed the spinal cord compressed at the same level by a low-intensity-signal lesion. Laminectomy and removal of the ossfied ligamenta flava improved her neurological dysfunction. The usefulness of the MRI in the neuroradiological diagnosis was confirmed.

Female↗
PubMed1988

Study on the receptor subtypes mediating the analgesic action of an enkephalin analog, Tyr-D-Met(O)-Gly-EtPhe-NHNHCOCH3.AcOH (EK-399).

The analgesic action of the enkephalin analog EK-399 (Tyr-D-Met(O)-Gly-EtPhe-NHNHCOCH3.AcOH) and the subtypes of the opiate receptors mediating the action were studied. The analgesic effect of subcutaneously injected EK-399 was ten times as potent as that of morphine in the rat tail flick test. EK-399 had a longer latency time and duration time than morphine. The analgesic action of EK-399 injected into the rat spinal subarachnoid space was about 800 (1800 in molar ratio) times as potent as that of morphine in the hot plate test. EK-399 had high affinities for both mu and delta opiate receptors in the rat brain receptor binding assay. The apparent pA2 values with naloxone were 7.65 for morphine and 5.98 for EK-399 in the rat tail flick test; the difference was significant. A cross tolerance between EK-399 and morphine was examined in the rat tail flick test. Although morphine tolerant rats showed no tolerance to EK-399, EK-399 tolerant rats showed a clear tolerance to morphine. These results indicate that EK-399 has a potent and long lasting analgesic effect via opiate receptors in rats. In addition to mu-receptors, delta-receptors may be involved in its analgesic mechanism.

Analgesics↗
PubMed1988

Progressive glomerulosclerosis develops in transgenic mice chronically expressing growth hormone and growth hormone releasing factor but not in those expressing insulinlike growth factor-1.

An increase in glomerular size occurs in normal maturation after subtotal renal ablation and disease states such as diabetes mellitus. The role that growth hormone (GH), growth hormone releasing factor (GHRF), and insulinlike growth factor-1 (IGF-1) play in these processes has been investigated using transgenic mice chronically expressing these hormones. The glomeruli were enlarged in all 3 strains of mice. Mesangial proliferation followed by progressive glomerulosclerosis was observed in the GH and GHRF animals only. In the IGF-1 mice the large glomeruli remained morphologically normal except for the enlargement. These data suggest that the glomerulosclerosis was due, in part, to disordered mesangial cell growth in response to circulating GH. The mesangial lesions in mice with chronically high plasma GH levels mimicked those in human diabetes mellitus. These models provide a means to study the hormonal regulation of glomerular growth and the role that specific hormones might play in the pathogenesis of glomerulosclerosis.

Animals↗
PubMed1988

Sudan I as a cause of pigmented contact dermatitis in "kumkum" (an Indian cosmetic).

"Kumkums" are coloured cosmetics frequently applied to the center of the forehead by Hindu women. Pigmented allergic contact dermatitis to "kumkum" was reported recently. It was associated with Brilliant Lake Red R and Sudan I allergy. These might be the causative allergens. Three of 7 brands of red "kumkums" analyzed by gas chromatography-mass spectrophotometry were found to contain various concentrations of Sudan I. They ranged from 2.789 mg/gm to 8.694 mg/gm. Sudan I is probably the cause of pigmented allergic contact dermatitis in red "kumkum".

Cosmetics↗