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Biomedical subjects

K Hara

Publications and source records attributed to K Hara.

At least 559 records · Page 31Linked to original sources
PubMed1993

Menatetrenone inhibits bone resorption partly through inhibition of PGE2 synthesis in vitro.

We studied the effect of menatetrenone, a vitamin K2 homolog, on bone resorption stimulated by interleukin-1 alpha (IL-1 alpha), prostaglandin E2 (PGE2), parathyroid hormone (PTH), and 1,25-dihydroxyvitamin D3 [1,25-(OH)2D3]. Bone-resorbing activity was assessed by measurement of calcium and hydroxyproline in the media and calvariae. IL-1 alpha (0.1-100 U/ml), 1,25-(OH)2D3 (10(-10)-10(-7) M), PGE2 (10(-9)-10(-6) M), and PTH (3 x 10(-8)-3 x 10(-7) M) dose dependently increased the levels of calcium and hydroxyproline in the medium. Indomethacin (10(-6) M) completely inhibited bone resorption induced by IL-1 alpha and partially inhibited bone resorption induced by 1,25-(OH)2D3. However, indomethacin did not affect the action of PGE2 or PTH. Menatetrenone (3 x 10(-6)-3 x 10(-5) M) inhibited the bone resorption induced by IL-1 alpha (2 U/ml), PGE2 (10(-7) M), PTH (3 x 10(-7) M), and 1,25-(OH)2D3 (3 x 10(-10) M) in a dose-dependent manner. Menatetrenone also inhibited the PGE2 production stimulated by IL-1 alpha. These results indicate that menatetrenone may inhibit bone resorption through at least two different mechanisms; one possibly is an inhibitory effect on prostaglandin production.

Animals↗
PubMed1993

Correlation between HPV positivity and state of the p53 gene in cervical carcinoma cell lines.

Human papillomavirus (HPV) infection is clearly associated with cervical carcinomas, yet it is also true that there are cervical carcinomas in which HPV DNA is absent. We examined eight established cell lines derived from cervical carcinomas for the presence of mutations of the p53 antioncogene in relation to the presence of HPV DNA sequences. Of these eight cell lines, seven were positive for HPV DNA and the remaining one was negative for HPV DNA. Single-strand conformation polymorphism analyses revealed a point mutation of the p53 gene in the cell line in which HPV DNA was absent. Sequencing analysis revealed a single-base mutation at codon 273 from CGT to CAT(Arg-->His) and immunocytochemical studies provided evidence that the p53 protein was overexpressed in this cell line. Our observations suggest that the loss of normal p53 gene function may be linked to the oncogenesis of cervical carcinoma.

Adenocarcinoma↗
PubMed1993

DNA-sequence rearrangement required for the adaptation of JC polyomavirus to growth in a human neuroblastoma cell line (IMR-32).

Infection of a human neuroblastoma cell line (IMR-32) with the JC polyomavirus (JCV) strain Mad-1 with subsequent serial passage results in the generation of a virus adapted to growth in IMR-32 (K. Akatani, M. Imai, M. Kimura, K. Nagashima, and N. Ikegami, J. Med. Virol., in press). To understand the basis of this adaptation, we molecularly cloned JCV DNAs from the adapted virus. The cloned JCV DNAs consisted of essentially three species (M1-IMRa, -IMRb, and -IMRc) with rearranged regulatory regions. Two TATA sequences are present in the regulatory region of the parental virus Mad-1, but one distal from the origin of replication was commonly deleted in M1-IMRa, -IMRb, and -IMRc. We showed that these regulatory regions were required for the efficient growth of JCV in IMR-32. Various JCV strains should be propagated in IMR-32, if their regulatory regions are replaced with those defined in this study. Since it is difficult to propagate JCV in cells other than primary human fetal glial cells, this system may be useful for structural and immunological studies of JCV.

Adaptation, Biological↗
PubMed1993

Degeneration of anterior horn cell in neuronal type of Charcot-Marie-Tooth disease (hereditary motor and sensory neuropathy type II): a Golgi study.

A morphological study using the Golgi impregnation method was carried out on the anterior horn cells at cervical (C), thoracic (Th), and lumbar (L) levels of the spinal cord in a patient with neuronal type of Charcot-Marie-Tooth disease (hereditary motor and sensory neuropathy type II) and an age-matched control. The present study demonstrated an uneven cell body surface, loss of cells (particularly large cells), loss of dendrites, reduced dendritic extent and an irregular surface and shape of dendrites at the C and L levels. In contrast, hematoxylin and eosin and Klüver-Barrera staining showed only simple atrophy or no change. The Th level of the patient showed none of these changes. Our results suggest that the degeneration or loss of dendrites of anterior horn cells by the Golgi staining method, which is most severe at the L level, is closely related to clinical findings such as muscle atrophy and weakness in neuronal type of Charcot-Marie-Tooth disease.

Aged↗
PubMed1993

Primary squamous cell carcinoma of the breast in a pregnant woman: report of a case.

Although reports on primary squamous cell carcinoma of the breast have been increasing in number, the morbidity rate of the disease is comparatively low. Its onset in pregnant women, especially, is quite rare. We herein report a case of primary squamous cell carcinoma of the breast in a pregnant woman. A 33-year-old woman was admitted with a lump in the right breast and an abnormal bloody nipple discharge. The breast mass was 5.6 x 5.4 cm in size, and both ultrasonogram and CT scanning showed that it consisted of a cystic tumor for the most part. A large amount of bloody cystic fluid was aspirated by fine-needle aspiration; squamous cell carcinoma of the breast was suspected by a cytological study on the fluid. Twelve days after an induced abortion was performed, a modified radical mastectomy was carried out. Histological findings of the resected specimen demonstrated that the tumor was squamous cell carcinoma which had been well differentiated with partial keratinization and cancer pearls. Noninvasive ductal carcinoma was also observed in a very small region of the specimen, which indicated that the tumor was probably originally adenocarcinoma which later transformed into squamous cell carcinoma.

Adult↗
PubMed1993

High detection rates of cryptococcal antigen in pulmonary cryptococcosis by Eiken latex agglutination test with pronase pretreatment.

Two different kits for the detection of serum cryptococcal antigen in patients with pulmonary cryptococcosis were evaluated. The Eiken test (the Eiken Co., Tokyo), which uses pronase for pretreatment of serum, was compared with the Crypto-LA test (International Biological Laboratories, Cranbury, NJ), which did not use pronase prior to testing. Cryptococcal antigen was detected in 21 of 23 patients (91%) with the Eiken test and in only 10 of 23 patients (43%) with the Crypto-LA test (p < 0.01 by McNemar test). However, the sensitivity of two tests was identical without use of pronase, as both tests could detect as little as 10(4) cells/ml of Cryptococcus neoformans and 10 ng/ml of capsular polysaccharide of C. neoformans. In those serum specimens for which both tests were positive, titers were much higher for the Eiken test, but there was a statistically significant correlation between the two tests (coefficient correlation 0.79, p < 0.01). Cryptococcal antigen titer levels measured by the Eiken test correlated well with clinical courses. There was one false-positive reaction among 82 sera of non-cryptococcal patients. Pronase enhanced the sensitivity of the Eiken test, which appeared to be useful in patients with pulmonary cryptococcal disease, and its use may prevent unneeded lung biopsies.

Adult↗
PubMed1993

Carcinoma of duodenal bulb arising from the Brunner's gland.

A 75-year-old man was diagnosed as having a sessile tumor measuring 1.4 x 1.0 cm in size in the duodenal bulb after upper gastroduodenal series. The biopsy specimens revealed a proliferation of the adenomatous glands showing an acinar structure with papillary infolding; type III mucus, which is characteristic of Brunner's glands. Antral glands and mucus neck cells of the fundic glands were also observed in the adenomatous glands by concanavalin A staining. Thus, it was clear that the tumor had originated from the Brunner's glands. Three years and four months later, the sessile tumor had developed into a fungating ulcerated tumor via a polypoid form. The biopsy specimens revealed a papillary adenocarcinoma with foci of undifferentiated carcinoma. Retrospectively, the adenomatous glands in the biopsy taken from the sessile tumor should have been regarded as low grade carcinoma. Therefore, we propose that when a polyp or tumor shows an increase in size or change in macroscopic appearance, surgery should be considered.

Adenocarcinoma, Mucinous↗
PubMed1993

A case of inflammatory malignant fibrous histiocytoma of the colon.

Primary malignant fibrous histiocytoma seldom occurs in the alimentary tract. This report documents a case in which a 50-year-old man presented with abdominal fullness and anorexia, together with inflammatory reactions such as fever, leukocytosis, an elevated erythrocyte sedimentation rate and positive CRP. Radiologic and endoscopic studies revealed a large mass in the ascending colon. The histology of the resected tumor revealed inflammatory malignant fibrous histiocytoma, a histologic subtype which is rare among not only soft tissue fibrous but also as gastrointestinal histiocytomas. The inflammatory reactions disappeared following resection of the tumor. Although we suspected that the tumor produced granulocyte colony-stimulating factor because of the slightly elevated serum level and the characteristics of the tumor histology, an immunohistochemical study failed to show the G-CSF production by the tumor cells.

Colon↗
PubMed1993

Differences in the assessment of postoperative pain when evaluated by patients and doctors.

This study was undertaken to compare the assessment of pain intensity by 59 patients and by their doctors according to a visual analogue scale (VAS) at rest and when coughing at 5 and 20 hr after major abdominal surgery. The rating given by the patients, who received epidural analgesia to relieve postoperative pain, was significantly above, and moreover, significantly correlated with that given by the doctors at any time or under any condition of the assessment. However, the correlation between the ratings given by patients and doctors at rest at 5 hr after surgery was low (r = 0.39, rs = 0.38) and significantly different from that when coughing at 20 hr after the operation (r = 0.79, rs = 0.80). Our findings indicate that the assessment of postoperative pain may be associated with some unreliability, especially during early periods, when using the subjective or objective-rated VAS at rest separately, and thus requires the combined use or the concomitant use of the VAS when coughing. Substitutional use of the objective-rated VAS for the subjective-rated VAS is not advised.

Journal Article↗
PubMed1993

Polymerase chain reaction analysis of human papillomavirus in adenocarcinoma and adenosquamous carcinoma of the uterine cervix.

Thirty-two cervical adenocarcinomas and adenosquamous carcinomas were examined to search for human papillomaviruses (HPVs) using the polymerase chain reaction system. Human papillomavirus type 16 (HPV16) and type 18 (HPV18) deoxyribonucleic acid was detected in 22% and 16% of these carcinomas, respectively. HPV16 was the most common type in both adenocarcinoma and adenosquamous carcinoma, and the mean age of the HPV negative patients was significantly higher than that of HPV positive patients. There may be an association between HPVs and the development of certain adenocarcinomas and adenosquamous carcinomas of the cervix.

Adenocarcinoma↗
PubMed1993

Isolation of a subclonal cell line of PC12 transfected with dexamethasone-regulated ras oncogene: morphological differentiation, biochemical properties, and tumorigenicity.

We have isolated and characterized a new subclonal cell line designated as MR31, which was obtained by transfection of PC12 cells with a glucocorticoid-regulated ras oncogene. The mRNA derived from the c-Ha-ras gene was proved to be expressed on exposure of the MR31 cells to dexamethasone, the highest value being attained at 8 h. MR31 cells rapidly extended neurite-like processes within 24 h in response to dexamethasone as well as nerve growth factor (NGF). The time of onset of neurite outgrowth induced by dexamethasone corresponded to the time when the highest ras mRNA level was observed. The catecholamine content of MR31 cells was found to be twice that of PC12 cells. A time course study on the effects of dexamethasone or NGF on cells showed that the former caused an increase in dopamine, a major catecholamine, to twofold the control level at 48 h after the treatment, while the latter caused a decrease in the dopamine level. These effects on catecholamines were almost the same in MR31 and PC12 cells. The acetylcholinesterase activity of MR31 cells was enhanced by both dexamethasone and NGF, whereas that of PC12 cells was enhanced by NGF, but not by dexamethasone. The changes in acetylcholinesterase activity were correlated with neurite outgrowth. Electron-microscopically, MR31 cells were not different from PC12 cells. MR31 cells exhibited extremely decreased tumorigenicity as compared with PC12 cells. The morphological and biochemical properties of MR31 cells remained constant, even after repeated passages.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed1993

Sympathoneural and haemodynamic characteristics of young subjects with mild essential hypertension.

OBJECTIVES: Whether muscle sympathetic nerve activity (MSNA) is increased in young subjects with mild essential hypertension has not been firmly established, and the potential haemodynamic correlates of any such increase have not been specifically investigated. The objectives of this study were to quantitate MSNA from the peroneal nerve of young subjects with mild hypertension, to determine the haemodynamic and neurohumoral correlates of sympathetic vasoconstrictor nerve traffic in such subjects, and to document the stability of these observations. DESIGN: Twelve young untrained subjects with mild essential hypertension (mean age 31 years, average clinic blood pressure 151/95 mmHg) and 11 age- and weight-matched normotensive subjects were studied on two sessions, at least 1 month apart, at the same time of day and under identical laboratory conditions. METHODS: Blood pressure (non-invasive), microneurography (MSNA; peroneal nerve), cardiac output and calculated total peripheral resistance (echocardiography and continuous-wave Doppler) and calf blood flow and resistance (plethysmography) were recorded during supine rest and assessed for condition and study order effects by two-way analysis of variance. Reproducibility of MSNA was quantified by the standard deviation of the mean difference (SDD) between the values obtained on the two study days. RESULTS: Muscle sympathetic nerve burst frequency and incidence, calf vascular resistance and cardiac output and index were significantly higher in hypertensive subjects, whereas heart rate, total peripheral resistance, plasma noradrenaline and plasma atrial natriuretic factor concentrations were similar in the two groups. There was no study order effect, in either group, on mean values for MSNA or these haemodynamic variables, but the SDD (day 1-day 2 variation) in muscle sympathetic burst frequency was significantly greater in hypertensive subjects. CONCLUSIONS: Mild essential hypertension in young subjects can be characterized by augmented MSNA as measured from the peroneal nerve, greater between-session variation in sympathetic burst frequency (but no study order effect), and increased calf vascular resistance and cardiac output. These sympathoneural and haemodynamic alterations are potential mechanisms of primary hypertension.

Adult↗
PubMed1993

Purification and immunohistochemical localization of aspartic proteinases in rat epidermis.

Investigation of skin cathepsin E (EC 3.4.23.-) has been totally ignored compared to skin cathepsin D (ED 3.4.23.5). In this study both cathepsins E and D were simultaneously purified to homogeneity up to 370 and 640 times, respectively, from 2-day-old rat epidermis. The total aspartic proteinase activity of rat epidermis detected after Q-Sepharose column chromatography was attributed to 27% cathepsin E, 63% cathepsin D, and 10% other enzymes. The purified enzymes showed that cathepsin E (90 kDa) is a dimer of 45 kDa subunits whereas cathepsin D is a monomer of 42 kDa. Other biochemical properties of epidermal cathepsins E and D were similar to those reported from other tissue sources. Immunologically cathepsins E and D were distinct from each other and localization of the two enzymes differed in both rat and human skin by immunohistochemistry. Cathepsin E was distributed diffusely in the cytoplasm of almost all epidermal cells, though its concentration increased above suprabasal cells, whereas cathepsin D appeared in particulate form only in cells of the granular layer. The findings indicate that two aspartic proteinases that have similar enzymatic properties exist in the epidermis. They are, however, differentially distributed in the organ, presumably for different functions during the process of keratinization.

Animals↗
PubMed1993

An evaluation of serodiagnostic tests in patients with candidemia: beta-glucan, mannan, candida antigen by Cand-Tec and D-arabinitol.

The serodiagnostic tests, beta-glucan, mannan, candida antigen by Cand-Tec, and D-arabinitol were evaluated in 10 patients with candidemia, 14 patients with suspected fungemia, and 10 healthy persons. By blood culture or lysis centrifugation, C. albicans was isolated from 5 patients, C. parapsilosis from 4, and C. tropicalis from 1 patient; no organisms were isolated from the 14 patients with suspected fungemia or the 10 healthy subjects. Beta-glucan was measured by the difference between two chromogenic limulus tests (Endotoxin test-D and Endospecy), which was more than 60 pg/ml in 7 of 9 (78%) candidemic patients and 1 of 12 (8%) patients with suspected fungemia. Mannan was positive in 6 of 10 (60%) candidemic patients and 1 of 13 (8%) patients with suspected fungemia. Both antigens were very sensitive and highly specific for candidemia. However, the Cand-Tec assay was less specific, because titers of more than 4 were observed in 5 of 14 (34%) patients with suspected fungemia. D-Arabinitol was the least sensitive, because a D-arabinitol/creatinine ratio greater than 2.0 mumol/mg was observed in only 2 of 7 (29%) candidemic patients. The titers of serodiagnostic tests decreased after successful treatment with an anti-fungal agent. Our results show that the combined use of the assays in necessary for accurate serological diagnosis of candidemia.

Adolescent↗
PubMed1993

Melanocytic lesions in lymph nodes associated with congenital naevus.

Two cases of melanocytic lesions in lymph node associated with congenital naevus are presented. The first was a 30-year-old man with a nodular melanoma arising in a small congenital naevus. The second was a 2-year-old male infant with a giant congenital naevus. In both cases, naevus cell aggregates were observed in the capsule, trabeculae, perisinusoidal areas and lymphatic vessels surrounding the nodes. In the first case, clusters of large atypical melanocytes were present amongst naevus cell aggregates in the perisinusoidal areas as well as in the lymphoid parenchyma. Between the naevus cells and large atypical melanocytes, transitional forms were observed which supports the idea that the presence of large atypical melanocytes is indicative of benign naevus cells. In the second case, marginal sinuses were packed with clusters of large melanin-rich cells. Immunohistochemically, these cells were S-100 protein negative, but ultrastructural studies proved them to be melanocytes. They were considered indicative of spread of benign naevus cells via lymphatic vessels. Arrested migration of naevus cells during embryogenesis and benign spread of naevus cells are possible explanations for the histogenesis of naevus cell aggregates in lymph nodes associated with congenital naevus.

Adult↗
PubMed1993

Intractable hiccups and sleep apnea syndrome in multiple sclerosis: report of two cases.

Two cases of multiple sclerosis associated with intractable hiccups (IH) and sleep apnea syndrome (SAS) are reported. Lesions were detected in the tegmentum of the medulla oblongata by magnetic resonance imaging. In one case, high dose methylprednisolone was remarkably effective for the IH. For the SAS, amitriptyline was effective in one case. The IH and SAS are thought to be important symptoms when a lesion occurs in the tegmentum of the medulla oblongata, including the paramedian and lateral reticular formations. If IH appears in conjunction with a lesion in the tegmentum of the medulla oblongata, one must be vigilant for the development of SAS.

Amitriptyline↗