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S Mikami

Publications and source records attributed to S Mikami.

At least 19 recordsLinked to original sources
PubMed1998

Hepatocellular carcinoma with chondrosarcomatous variation: case report with immunohistochemical findings, and review of the literature.

Hepatocellular carcinoma with chondrosarcomatous variation is very rare. We report a case with the results of pathology examination, and review the literature. The patient, a 72-year-old may had a very large tumor in the liver revealed during follow-up for diabetes mellitus. The liver mass, which was 14 cm in diameter, was diagnosed as hepatocellular carcinoma by abdominal ultrasonography. Anterior segmentectomy and partial liver resection were performed. Histopathology examination revealed that the tumor consisted of two different components: the major one was hepatocellular carcinoma (HCC), which occupied most of the tumor; and a sarcomatous component, which occupied a smaller area, and included spindle-shaped cells with chondroscarcomatous variation. Intrahepatic metastases and tumor thrombi of HCC were also found in portal and hepatic veins. Investigations of the immunohistochemical localization of keratin (KRT), vimentin (VMT), and S-100 protein (S 100) were performed by the avidin-biotin complex method. Some of the spindle cells were immunohistochemically positive for both KRT and VMT, and the chondrosarcomatous cells were positive for S 100. These results strongly suggested that the sarcomatous lesion resulted from a sarcomatous change of HCC.

Aged↗
PubMed1998

Immunohistochemical analysis of TrkA neurotrophin receptor expression in human non-neuronal carcinomas.

The Trk family of tyrosine protein kinase receptors plays a significant role in the development and maintenance of neural tissues. It has been recently shown that Trk receptors are also expressed by a wide range of normal non-neuronal tissues in humans in a cell type-specific manner. In the present study, the expression patterns of TrkA in 337 non-neuronal invasive carcinomas of 15 different human tissues were investigated immunohistochemically. Overall, 133 (39%), 101 (30%) and 103 (31%) tumors exhibited strong, moderate and no TrkA immunoreactivity, respectively. Esophageal and thyroid carcinomas expressed high levels of TrkA, whereas the levels in gastric and colon cancers were low. TrkA expression was detected not only in carcinomas originating from TrkA-positive normal counterpart tissues, including the esophagus, breast, lung and uterus, but also in those from TrkA-negative tissues/cells of the thyroid, liver and ovary. Immunostaining for nerve growth factor-beta, the specific ligand for TrkA, in esophageal and breast carcinomas demonstrated its immunoreactivity in stromal fibroblasts and some TrkA-expressing tumor cells. These results suggest that paracrine/autocrine regulation via stromal/tumoral NGF-tumoral TrkA interaction may be involved in the growth of certain non-neuronal carcinomas.

Breast Neoplasms↗
PubMed1998

G370C mutation in the FGFR3 gene in a Japanese patient with thanatophoric dysplasia.

Thanatophoric dysplasia (TD) is a sporadic lethal skeletal dysplasia with micromelic shortening of the limbs, relative macrocephaly, platyspondyly and reduced thoracic cavity. It has recently been reported that TD is caused by mutations in the FGFR3 gene. In the present study, we report a missense mutation in the FGFR3 gene in a Japanese patient with TD. The patient was noticed to have typical features of TD type 1 (TD1) at birth. The genomic DNAs of the patient and his parents were isolated from whole blood. DNA fragments of the FGFR3 gene were amplified by polymerase chain reaction, and directly sequenced. The patient was revealed to be heterozygous for a missense mutation G370C, changing codon 370 (GGC) encoding Gly to TGC encoding Cys, but his parents did not have the G370C mutation. The G370C mutation introduces an unpaired cysteine residue in the extracellular domain of FGFR3, which may result in formation of an intermolecular disulfide bond between two mutant FGFR3 monomers and their constitutive activation. In conclusion, we have identified the G370C mutation in the FGFR3 gene in a Japanese TD1 patient.

Alleles↗
PubMed1998

[Percutaneous transhepatic portal vein embolization for hepatocellular carcinoma].

We report on the significance of percutaneous transhepatic portal vein embolization (PTPE) for hepatocellular carcinoma based on the results in 111 patients who underwent PTPE in our hospital. All patients tolerated the procedure without major complications, although transient elevations in serum transaminase levels were noted. Immediately after PTPE, the portal pressure increased. Portal venous flow at the main portal trunk decreased, but the flow in the nonembolized part of the liver increased. PTPE produced regenerative hypertrophy in the nonembolized part of the liver, which was mainly predicted by the volume of the embolized area and the morphological score of the hepatitis or cirrhosis. PTPE increased the safety of subsequent hepatectomy and expanded the indications for hepatectomy. PTPE is also useful as a type of multiplicative therapy for hepatocellular carcinoma.

Carcinoma, Hepatocellular↗
PubMed1997

Low-dose N omega-nitro-L-arginine methyl ester treatment improves survival rate and decreases myocardial injury in a murine model of viral myocarditis induced by coxsackievirus B3.

Recent reports demonstrated the expression of inducible-type NO synthase in the heart of viral myocarditis. Since NO has multiple biological actions, a substantial amount of NO produced in the diseased heart may act either as a cytotoxic or as a cytoprotective molecule in the process of myocarditis. In the present study, we examined the effect of inhibition of NO synthesis on the mortality and the extent of myocardial injury in a murine model of coxsackievirus B3-induced myocarditis. We fed the infected mice drinking water containing a relatively low concentration (0.37 mmol/L) of N omega-nitro-L-arginine methyl ester (L-NAME) for 14 days after virus inoculation. This dose of L-NAME did not change virus titers in the heart. However, L-NAME-fed mice showed a significant reduction in mortality compared with those fed normal drinking water (nontreated mice). On the contrary, mice given a higher concentration of L-NAME (3.7 mmol/L) exhibited increased mortality. In addition, mice fed a low concentration of L-NAME showed reductions in the severity of heart failure and in the area of myocardial necrosis. Although systemic blood pressure was reduced in nontreated mice, in mice fed a low concentration of L-NAME, it was maintained at a level similar to that in uninfected control mice, L-NAME-treated mice also exhibited a reduction in the degree of inflammatory cell infiltration associated with decreased production of tissue prostaglandin E2 levels in the heart compared with nontreated mice. Therefore, NO is likely to be involved in the pathogenic mechanisms of myocardial injury and resultant cardiac dysfunction in a murine model of coxsackievirus B3-induced viral myocarditis.

Animals↗
PubMed1996

Expression of nitric oxide synthase in a murine model of viral myocarditis induced by coxsackievirus B3.

Nitric oxide is known to participate in the immune and inflammatory processes. In this study, we investigated the production of nitric oxide (NO) in murine viral myocarditis induced by coxsackievirus B3. The expression of inducible NO synthase (iNOS) mRNA in the heart first appeared on day 4 after virus inoculation and it was detectable for one month by reverse transcriptase-polymerase chain reaction (RT-PCR) methods. iNOS activity which was determined by the conversion of L-[3H]arginine to L-[3H]citrulline was increased on day 4 and revealed its peak on day 8. Immunohistochemistry on day 7 showed increased iNOS staining mainly in infiltrating macrophages and polymorphonuclear leukocytes. Thus, NO is thought to be produced in the heart and play an important role in a murine model of coxsackievirus B3-induced viral myocarditis.

Animals↗
PubMed1996

Immunohistochemistry and angiography in adenomatous hyperplasia and small hepatocellular carcinomas.

The sinusoidal structure and blood supply of 38 liver nodules less than 2 cm in diameter were investigated. There were 18 cases of adenomatous hyperplasia (AH) and 20 cases of hepatocellular carcinoma (HCC). Growth pattern, encapsulation and vascularity were examined, and immunohistochemistry performed for factor VIII related antigen (factor VIII), type IV collagen (collagen IV), laminin and CD68. There were significant differences between AH and small HCC, except for the expression of CD68. There were differences in tumor size, vascularity and the components of the basement membrane between AH and small, well differentiated HCC. The cases of AH were supplied by the portal system and maintained the sinusoidal structure, but small well-differentiated' HCC were supplied by a mixture of portal and arterial vessels. In spite of their small size, moderately and poorly differentiated HCC had capillary and were supplied by branches of the hepatic artery.

Aged↗
PubMed1996

Endothelial constitutive nitric oxide synthase protein and mRNA increased in rabbit atherosclerotic aorta despite impaired endothelium-dependent vascular relaxation.

Atherosclerotic arteries are well known to exhibit impaired endothelium-dependent relaxation (EDR), but the exact mechanism of this impairment remains unclear. Recently, endothelial constitutive nitric oxide synthase (ECNOS), which generates nitric oxide and mediates EDR, was cloned, and ECNOS mRNA expression was reported to be modified by various cytokines, lipoproteins, and shear stress. To investigate the expression of ECNOS mRNA and protein in atherosclerotic arteries with impaired EDR, thoracic aortas isolated from Watanabe heritable hyperlipidemic (WHHL) rabbits were examined by using in situ hybridization and immunohistochemistry. Compared with thoracic aortas from Japanese White rabbits, WHHL aortas exhibited significantly impaired EDRs, although both in situ hybridization and immunohistochemistry exhibited enhanced expression of ECNOS mRNA and protein in WHHL aortas. There was no significant relationship between expression of ECNOS mRNA and protein of endothelial cells and age of the examined WHHL aortas. These data suggest that the mechanism of impaired EDR in atherosclerotic arteries is not due to the decrease in ECNOS mRNA and protein.

Acetylcholine↗
PubMed1995

A case of multiple osteochondroma in the rat.

The occurrence of spontaneous osteochondroma in rats is extremely rare and only a few cases have been reported. Spontaneous multiple osteochondroma was found in a male SD strain rat, at the age of 58 weeks from the control group in a toxicity study. Histological findings of both a walnut-sized mass involving the humerus and scapula of right forelimb and a soybean-sized mass adjacent to the costochondrial junction of the right posterior rib were similar in appearance. The outer layer of the tumors consisted of hyaline cartilage and the core of the tumors consisted of trabecular bone with abundant fatty bone marrow. The periosteum of the surface was continuous with that of the parent bone, and cortical bone and the medullary cavity of the parent bone communicated with those of the tumors. Because of showing progressive enlargement, multiple osteochondromas in the rat were considered to be neoplastic in nature.

Animals↗
PubMed1995

[Pregnenolone].

Explore the source record for details and available documents.

Adolescent↗
PubMed1993

Relationship of urinary sodium and potassium and of urinary sodium/creatinine, potassium/creatinine and sodium/potassium ratios to stomach cancer and cerebrovascular disease mortalities in Japanese women.

To test Joossens's hypothesis that salt is a common cause of both cerebrovascular disease (CVD) and stomach cancer (SC), the standardized mortality ratios (SMRs) of SC and CVD were related to urinary Na and K and urinary Na/creatinine (Cr), K/Cr, and Na/K ratios. Fifty spot urine of females between 40 to 69 years was collected from each of 169 municipalities (88 urban and 81 rural) covering all prefectures in Japan using the filter paper sampling technique in 1985. While the SMR levels of CVD correlated significantly with Na, Na/Cr and Na/K, the SMR levels of SC showed no correlation with Na, K, Na/Cr, K/Cr or Na/K. It was therefore concluded that the geographical distribution of female SMR for SC could not be explained using only the urinary Na excretion as an index of Na intake, and that multiple risk factors and risk reducing factors should be taken into account to explain the distribution.

Adult↗
PubMed1990

The third nationwide survey in Japan of vitamin K deficiency in infancy.

The occurrence of hemorrhagic disease due to vitamin K (VK) deficiency beyond the neonatal period has come under investigation in Japan. In 1980 the 1st nationwide survey was conducted in Japan by Nakayama and others, and was followed by the 2nd nationwide survey in 1985 by Hanawa. The present survey was designed to further monitor the incidence of this disease in Japan during the 3-year period from July 1985 to June 1988. Questionnaires were sent to 1,315 hospitals having more than 200 beds, located throughout Japan. Responses were received from 775 hospitals, for an answer rate of 58.9%. The total number of reported cases was 175, including 129 idiopathic type, 28 secondary type and 18 near-miss type. In this survey it was revealed that the incidence rate of the idiopathic type of vitamin K deficiency in infancy (VKDI) has decreased remarkably, to about one-fourth that reported in the first survey. The declining incidence rate of VK deficiency in Japan is considered to be the result of ever more widespread prophylactic administration of VK during the neonatal period, as most occurrences of VK deficiency in infancy are preventable by prophylactic administration of VK from the neonatal period. However, in 16 cases of the idiopathic type of VK deficiency found in the present survey, VK had been administered at least once during or after the neonatal period. This shows the heterogeneity of this condition.

Female↗
PubMed1990

Immunohistochemical studies on the development of endocrine cells in the thyroid and parathyroid glands in the golden hamster.

The development of endocrine cells in the thyroid and parathyroid glands in the golden hamster was studied immunohistochemically in relation to the formation of these glands. The thyroid was formed on day 9 of gestation by the ventral outpocketing of the foregut between the first and second branchial pouches. The thyroid epithelial cells were faintly thyroglobulin-immunoreactive on day 10.5 of gestation. This immunoreaction became intense thereafter, but was almost confined to the cytoplasm of epithelial cells until birth. It appeared in the follicular lumen in newborn animals. The ultimobranchial body was derived from the fifth pouch and fused with the thyroid on day 12 of gestation. Calcitonin-immunoreactive cells first appeared on day 14 of gestation in the dorsomedial part of the thyroid derived from the ultimobranchial body and increased in number and intensity thereafter. Somatostatin-immunoreactive cells also appeared in the dorsomedial part of the thyroid derived from the ultimobranchial body on day 13 of gestation, and increased in number in newborn animals, but decreased thereafter. The parathyroid was derived from the third pouch, situated on day 13 of gestation on the dorsolateral side of the thyroid, and surrounded by a common capsule with the thyroid. Parathormone-immunoreactive cells first appeared on day 15 of gestation in the parathyroid and increased in number and intensity after birth.

Animals↗
PubMed1990

Evaluation of the individual effects of a health education program for sodium restriction by a simple method for measuring 24-hour urinary sodium excretion.

A simple method for measuring 24-hr urinary sodium excretion was applied to the evaluation of the individual effects of a health education program for sodium restriction in a rural community in Japan. Eighteen subjects (6 males and 12 females) between 35 and 72 years of age were advised to reduce their sodium intake. Twenty-four-hour urinary sodium, potassium excretion, and sodium/potassium ratio were measured using the simple method for seven consecutive days in three periods which were before the sodium restriction, 6 months after the sodium restriction, and 6 months after the end of the program. Mean sodium excretion of 18 subjects significantly decreased (p less than 0.05) after the end of the program. The reduced level was maintained until six months after the end of the program. Within individual cases, sodium excretion decreased significantly in subjects who had levels higher than 170 mmol at the initial stage. The reduced levels of sodium excretion were maintained until six months after the end of the program except for one subject. The subjects who had an initial level lower than 170 mmol of sodium, which is the upper limit of present recommendation for Japanese adults, did not change their levels.

Adult↗
PubMed1989

First trimester prenatal diagnosis of haemophilia A using factor VIII gene probe.

Accurate first-trimester prenatal diagnosis was achieved in a Japanese haemophilia A family by the use of a restriction fragment length polymorphism (RFLP) located within the F.VIII gene. Since the pregnant woman's heterozygosity for BclI polymorphism in F.VIII/intron 18 (F8A) probe was informative, chorionic villus sampling (CVS) was performed at 9 weeks of gestation. Restriction analysis showed that the fetus was heterozygous for the BclI site and had received a normal paternal X chromosome (0.9 kb) and a normal maternal X (1.2 kb). Therefore, we concluded that the fetus was a non-carrier female. Pregnancy went to term and woman gave birth to an apparently healthy female. At one week after birth a coagulation study confirmed that the newborn infant is not a carrier. The first-trimester prenatal diagnosis of haemophilia A is possible by CVS due to a RFLP in the F.VIII gene.

Blotting, Southern↗
PubMed1989

Effects of vitamin A deficiency on the function of pituitary-gonadal system in male rats.

The effects of vitamin A deficiency on the pituitary-gonadal function were examined by measurements of serum and pituitary level of pituitary hormones and serum testosterone concentration, and by investigations of histological changes in the testis and the pituitary gland in vitamin A-deficient (VAD) and supplemented (VAS) rats. The growth of VAD rats was retarded and their body weights were decreased after 9 weeks of experiments and attained about one half of the weight of control animals at 12 weeks. In the VAD rats, serum testosterone concentrations were decreased significantly compared with those in the VAS controls. Serum and pituitary concentrations of GH were significantly lower but those of LH were slightly lower in the VAD rats than those in the controls, while the serum FSH concentration was significantly higher than that in the control rats. The seminiferous tubules in the testes of VAD rats were comprised largely of Sertoli cells and a reduced number of spermatogonia and contained fibrous formation in their lumen. In the pituitary gland, GH cells were significantly reduced in number in the VAD rats, but gonadotropic (GTH) cells were increased remarkably in size and number, showing hypertrophy and vacuolation similar to those in castration cells. The cytological changes in the pituitary gland and the increased discharge of FSH represent a secondary and compensatory change similar to that seen following castration and vitamin E deficiency.

Animals↗