Biomedical subjects

K Murata

Publications and source records attributed to K Murata.

At least 181 records · Page 10Linked to original sources

PubMed1999

Multi-clonal expansion of unique human T-lymphotropic virus type-I-infected T cells with high growth potential in response to interleukin-2 in prodromal phase of adult T cell leukemia.

We established a simple IL-2-dependent colony-forming assay for T cells infected with human T-lymphotropic virus type-I (HTLV-I). IL-2-dependent cell lines were subsequently established by expanding individual colonies in liquid cultures. Lymphocyte-rich fractions were prepared from 31 HTLV-I carriers, 12 patients with smoldering ATL, 11 chronic ATL, 12 crisis ATL and 10 acute ATL. Primary colonies of CD4+ p19+ T cells were formed in all cases of carriers, smoldering and chronic ATL, and in 10 of 12 crisis cases. In contrast, no colony was formed from cells of patients with acute ATL. The rate of establishment of cell lines in HTLV-I carriers was significantly lower than that in patients of prodromal phase ATL. Cell lines established from cells of three prodromal cases were clonally identical to the parent ATL cells, while others had clonally distinct cell lines. Our results indicated the presence of four components of HTLV-I-infected T cells: (1) normal carrier T cells capable of forming colonies but not cell lines; (2) pre-malignant T cells capable of forming colonies as well as cell lines; (3) malignant T cells capable of forming colonies as well as cell lines; (4) fully malignant T cells unresponsive to IL-2. Our results suggest the presence of a multiclonal expansion of unique T cells in the prodromal phase of ATL, which have a high growth potential in response to IL-2. The coexistence of multiclonality with a dominant ATL clone may be closely related to the underlying pathology in HTLV-I leukemogenesis.

Case-Control Studies↗

PubMed1999

An assessment of the immunological environment based on intratumoral cytokine production in renal cell carcinoma.

OBJECTIVE: To assess the immunological relationship between tumour and host, focusing on the production of T-cell helper (Th) subset-derived cytokines in patients with renal cell carcinoma (RCC). PATIENTS AND METHODS: The study comprised 35 patients (19 men and 16 women, mean age 56.9 years, range 39-78) with RCC, who had undergone nephrectomy. Using enzyme-linked immunosorbent assays, the levels of Th1-derived cytokines were measured, including interleukin (IL)-2 and interferon (IFN)-gamma, and Th2-derived cytokines, including IL-4, IL-5, IL-6, IL-10 and others. RESULTS: There was no detectable IL-2 or IFN-gamma production (below the detection limit) except in two patients; IL-4 was produced in 18 patients (51%) and of these, 15 (43%) showed a higher level than the mean. IL-5 was produced in 12 patients (34%), all of whom showed a higher level than the mean, and IL-6 was produced in 32 (91%) of whom 10 (29%) showed a higher level than the mean. IL-10 was detected in 28 patients (80%) of whom 14 (40%) showed a higher level than the mean. The production of these cytokines was closely related to the stage and grade of malignancy. Furthermore, there were significant correlations between the levels of production of IL-4 and IL-5 (r2=0.92), IL-4 and IL-10 (r2=0.91), and IL-5 and IL-10 (r2=0.85). CONCLUSION: The intratumoral immunological environment in patients with RCC shows a tendency to produce Th2-related cytokines in accordance with the stage and grade; this suggests a role in humoral but not in cellular immunity.

Adult↗

PubMed1999

Codon 54 polymorphism of the fatty acid binding protein gene and insulin resistance in the Japanese population.

AIM: To determine the relationship of the polymorphism at codon 54 of the intestinal fatty acid binding protein gene (FABP2) with insulin resistance and susceptibility to Type 2 diabetes mellitus (DM) in the Japanese population. METHODS: We evaluated the polymorphism by the polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) in 150 Type 2 DM patients and 147 healthy control subjects. The frequency of alleles encoding threonine (Thr54) and alanine (Ala54) at codon 54 of FABP2 in Type 2 DM patients was compared with that of healthy controls. Insulin sensitivity was assessed by the hyperinsulinaemic euglycaemic clamp in Type 2 DM patients with Ala54 homozygotes, Ala54/Thr54 heterozygotes and Thr54 homozygotes and by homeostasis model assessment (HOMA) in the nondiabetic group. RESULTS: The frequency of alleles encoding Ala54 and Thr54 was 0.59 and 0.41 in Type 2 DM patients, respectively, similar to that observed in nondiabetic controls (0.64 for Ala54 and 0.36 for Thr54). Insulin sensitivity was not significantly different between subjects with and without Thr54 allele either within the DM group or healthy controls. CONCLUSIONS: The allele encoding threonine in the FABP2 does not predispose to Type 2 DM or insulin resistance in the Japanese population.

Carrier Proteins↗

PubMed1999

Transfer of a pedicled venous flap containing perivenous areolar tissue and nerve: an experimental study.

In this paper, we evaluated experimentally the feasibility of transferring a pedicled venous flap with perivenous areolar tissue into an ectopic site and investigated the role of each vein, the perivenous areolar tissue and nerve in the viability of pedicled venous flaps. Three groups of flaps were created using a rabbit-ear model: Group 1 (n = 11), containing perivenous areolar tissue and a draining vein; Group 2 (n = 10), perivenous areolar tissue, a draining vein and nerve; Group 3 (n = 10), only perivenous areolar tissue. Macroscopic, angiographic and histological assessments were performed 14 days after transfer. The total survival areas including superficial necrosis of Groups 1, 2 and 3 were 52.7%, 82.5% and 0%, respectively. There were significant differences in mean survival area and mean total survival area including superficial necrosis between Group 1 and Group 2 (P < 0.05). In contrast, all flaps in Group 3 became necrotic. These data suggest that a preserved vein is the necessary condition, and additional arterial flow through the preserved nerve and a small vascular network within the areolar tissue may play an important role in flap survival.

Animals↗

PubMed1999

Formation of mature egg envelope subunit proteins from their precursors (choriogenins) in the fish, Oryzias latipes: loss of partial C-terminal sequences of the choriogenins.

The inner layer of egg envelope of the medaka, Oryzias latipes, comprises two major groups of glycoprotein subunits, ZI-1,2 and ZI-3. Their precursor proteins, choriogenin H (Chg H) and choriogenin L (Chg L), respectively, are synthesized in spawning female liver. In the present study, the primary structures of the precursors and the corresponding mature subunits were compared by peptide mapping and amino acid sequencing to find what difference in their molecular structures is relevant to the assembly of the soluble precursors into the insoluble inner layer. The primary structures of the solubilized subunits were mostly identical to those of the respective precursors, but they lacked C-terminal partial sequences that their precursors possessed, namely, ZI-1,2 subunit was shorter than Chg H by 34 amino acid residues and ZI-3 was shorter than Chg L by 27 residues. In addition, a consensus amino acid sequence, Arg-Lys-X-Arg, was found at the putative cleavage sites in the C-terminal region of the precursors. It is conjectured that the truncation of the precursor proteins is prerequisite for formation of mature chorion subunit proteins and their assembly into chorion.

Amino Acid Sequence↗

PubMed1999

Trehalose embedding technique for high-resolution electron crystallography: application to structural study on bacteriorhodopsin.

Trehalose was compared with glucose in its use as an embedding medium for the preparation of two-dimensional crystals for electron crystallographic structure analysis. Purple membranes (two-dimensional crystals of bacteriorhodopsin) embedded in either sugar were studied in a 'partially hydrated' state as well as after 'drying' of the specimen. Diffraction patterns of the four conditions, all showing spots to a resolution better than 3.0 A, were analysed and merged. In the case of glucose embedded specimens, the merging R-factor obtained from the diffraction patterns of dried specimens was significantly better than the one obtained from partially hydrated specimens. In the case of trehalose embedding, the merging R-factor for partially hydrated specimens was significantly better than the dried one. The trehalose embedded, partially hydrated specimens gave the best merging R-factor in all four cases.

Bacteriorhodopsins↗

PubMed1999

Cardiovascular dysfunction due to shift work.

Electrocardiographic, biochemical, and physical data obtained from 237 shift and 115 day workers without any obvious disorders were assessed to clarify the impact of shift work on cardiovascular functions. The heart-rate corrected QT interval (QTc) was significantly longer in the shift workers than in the day workers. However, blood pressure, working duration, and biochemical and other data were comparable between the two work groups. When multiple regression analysis was used, shift/day work was significantly related to the QTc in all of the workers. The adjusted odds ratio of shift work to the prolonged QTc (> or = 440 ms1/2) was 8.15. The prolonged QTc has been thought to contribute to an increased risk of cardiac death. These findings, therefore, suggest that the increased risk for cardiovascular mortality in shift workers may be attributable to prolongation of the QTc.

Adult↗

PubMed1999

A case of Werner's syndrome associated with osteosarcoma.

We described a case of Werner's syndrome associated with osteosarcoma. A 37-year-old Japanese man was diagnosed as having Werner's syndrome by the presence of juvenile cataracts, skin sclerosis and hyperpigmentation of the feet, high-pitched voice, characteristic bird-like appearance of the face with beak-shaped nose, thinning of the entire skin and hyperkeratoses on soles, hyperlipemia, hyperuricemia, diabetes melitus, and the mutated responsible gene (WRN). He had a 3-month history of a tumor on his left forearm. Histologically, the tumor included four histological patterns; a malignant fibrous histiocytoma-like, a desmoid-like, a dermatofibrosarcoma protuberans-like, and a chondrosarcoma-like pattern. Tumoral osteoid formation was also found in the tumor. Therefore, the tumor was diagnosed as osteosarcoma.

Adult↗

PubMed1999

Assessment of ego state in anorexia nervosa and bulimia nervosa.

To clarify the effects of ego states on anorexia nervosa (AN) and bulimia nervosa (BN), the questionnaire of the Tokyo University Egogram (TEG) with critical parent, nurturing parent, adult, free child and adapted child scales was administered to 32 female AN patients aged 14 to 32 years (mean age 20 years) and 49 female BN patients aged 14 to 33 years (mean age 23 years). The scores on the critical parent and adapted child scales for AN were significantly lower than those for BN. A multiple logistic regression analysis including all of the TEG scales, age, duration of illness and education showed that the adapted child scale significantly discriminated between AN and BN. The adaptive ego state is suggested for differentiating between the two disorders.

Adaptation, Psychological↗

PubMed1999

Microbial system for polysaccharide depolymerization: enzymatic route for xanthan depolymerization by Bacillus sp. strain GL1.

An enzymatic route for the depolymerization of a heteropolysaccharide (xanthan) in Bacillus sp. strain GL1, which was closely related to Brevibacillus thermoruber, was determined by analyzing the structures of xanthan depolymerization products. The bacterium produces extracellular xanthan lyase catalyzing the cleavage of the glycosidic bond between pyruvylated mannosyl and glucuronyl residues in xanthan side chains (W. Hashimoto et al., Appl. Environ. Microbiol. 64:3765-3768, 1998). The modified xanthan after the lyase reaction was then depolymerized by extracellular beta-D-glucanase to a tetrasaccharide, without the terminal mannosyl residue of the side chain in a pentasaccharide, a repeating unit of xanthan. The tetrasaccharide was taken into cells and converted to a trisaccharide (unsaturated glucuronyl-acetylated mannosyl-glucose) by beta-D-glucosidase. The trisaccharide was then converted to the unsaturated glucuronic acid and a disaccharide (mannosyl-glucose) by unsaturated glucuronyl hydrolase. Finally, the disaccharide was hydrolyzed to mannose and glucose by alpha-D-mannosidase. This is the first complete report on xanthan depolymerization by bacteria. Novel beta-D-glucanase, one of the five enzymes involved in the depolymerization route, was purified from the culture fluid. This enzyme was a homodimer with a subunit molecular mass of 173 kDa and was most active at pH 6.0 and 45 degrees C. The enzyme specifically acted on xanthan after treatment with xanthan lyase and released the tetrasaccharide.

Bacillus↗

PubMed1999

[A study on the factors affecting friendship with HIV-infected students in high school: from the survey of AIDS related knowledge, information sources and attitudes in 1989 and 1992].

To clarify the factors affecting the friendship with human immunodeficiency virus (HIV)-infected persons, a self-reported questionnaire study was conducted in two high schools in Tokyo in 1989 and 1992. A complete set of responses was obtained from 541 (98%) and 517 (99%) students in 1989 and 1992, respectively. The following results were obtained: 1) The proportion of the students who received information on HIV/acquired immunodeficiency syndrome (AIDS) from school teachers in 1992 was higher than that in 1989 for both males and females. Similarly, for both males and females, the proportion of students with correct knowledge on HIV transmission was significantly higher in 1992. The proportion of the students who intended to have a friendship with a hypothetical HIV-infected classmate or close friend in 1992 was significantly higher. 2) The results of multiple logistic regression analysis indicated that such factors as having more correct knowledge on HIV transmission and considering the confidentiality of persons with HIV/AIDS were significantly related to having friendship with a hypothetical HIV-infected classmate for both 1989 and 1992; such factors as being a female and having an increasing risk of HIV infection were significantly related to the responses obtained for 1992.

Acquired Immunodeficiency Syndrome↗

PubMed1999

[Assessment of autonomic neurotoxicity of environmental and occupational factors as determined by heart rate variability: recent findings].

The measurement of heart rate variability (coefficient of variation of ECG R-R intervals) provides a promising approach for the objective assessment of the autonomic nervous function. It is noninvasive and clinically practical, although it tends to be distorted by confounding factors such as age, tobacco and alcohol. In particular, two components of the respiratory sinus arrhythmia with a high frequency (HF) of 0.15-0.4 Hz and Mayer wave related sinus arrhythmia with a low frequency (LF) of 0.04-0.15 Hz in the heart rate variability, which were computed by autoregressive spectral and component wave analyses, reflect parasympathetic and sympathetic activities, respectively. This article is intended to present an overview of research, utilizing this frequency domain method, in environmental and occupational health. The available literature, addressing the impact of some chemicals and work-related factors on the human autonomic nervous system, indicates that parasympathetic activity appears to be more vulnerable to these factors than does sympathetic activity. Since decreased cardiac vagal tone is associated with an increased risk of sudden cardiac death or coronary heart disease, attention should be directed to further discovery of hazardous factors in the environment and workplace, which may pose potential autonomic neurotoxic risks.

Autonomic Nervous System↗

PubMed1999

Safety assessment of transgenic potatoes with soybean glycinin by feeding studies in rats.

Feeding studies of transgenic potatoes with native and designed soybean glycinins in rats were done for four weeks. The designed glycinin has four additional methioninyl residues in the middle of the glycinin molecule. Rats were divided into four groups fed (I) only a commercial diet, (II) the diet plus non-transgenic potatoes, (III) the diet plus transgenic potatoes with native glycinin, and (IV) the diet plus transgenic potatoes with designed glycinin. Rats were fed 2,000 mg/kg-weight potatoes every day by oral administration. During the period tested, rats in each group (groups II, III, and IV) grew well without marked differences in appearance, food intake, body weight, or in cumulative body weight gain. No significant differences were also found in blood count, blood composition, and in internal organ weights among the rats after feeding potatoes (groups II, III, and IV) for four weeks. Necropsy at the end of experiment indicated neither pathologic symptoms in all rats tested nor histopathological abnormalities in liver and kidney. Judging from these results, the transgenic potatoes with glycinins are confirmed to have nearly the same nutritional and biochemical characteristics as non-transgenic one.

Animal Feed↗

PubMed1999

Quality and safety evaluation of genetically engineered rice with soybean glycinin: analyses of the grain composition and digestibility of glycinin in transgenic rice.

The composition of nutritionally and physiologically important molecules in transgenic rice with the soybean glycinin gene was determined and compared with that of a non-transgenic control. Except for the levels of protein, amino acids and moisture, no marked differences were found between the two kinds of rice. The protein content of the transgenic rice was about 20% higher than the control (control, 6.5 g/100 g; transgenic, 8.0 g/100 g) with a concomitantly lower moisture content. This increased protein content mainly resulted from the increased glycinin expressed in the transgenic rice, and the protein was susceptible to gastric and intestinal digestion juices. In parallel with the increased protein content, some important amino acids lacking in quantity in normal rice were replenished.

Amino Acids↗

PubMed1999

First report of Thelazia sp. from a captive Oriental white stork (Ciconia boyciana) in Japan.

Nematodes of the genus Thelazia were recovered from the cornea and inferior conjunctival sac of an immature Oriental white stork (Ciconia boyciana). The bird hatched and reared at the Toyooka Oriental White Stork Breeding Center, Hyogo Prefecture, Japan, but died of chlamydiosis. There were neither gross nor histopathologic ophthalmic lesions. The eye worm from a bird is believed to be first reported in Japan. As regarding reintroduction plan for the Oriental white stork, control measures for prevent further infection with the eye worm will be needed.

Animals↗

PubMed1999

Toxic shock-like syndrome resembling phlegmasia cerulea dolens.

A case of a 71-year-old Japanese woman with toxic shock-like syndrome is reported. She was admitted to the hospital because of swelling of the right leg. On admission, right lower leg was erythematous and swollen with an erosive lesion. On the second day, she rapidly fell into shock. Phlegmasia cerulea dolens caused by massive iliofemoral venous thrombosis was suspected because she had a history of deep venous thrombosis. But deep venous thrombus was not detected by venography at emergent surgery for thromboembolectomy. She died 38 hours after admission despite maximal supportive therapy. Group A beta-hemolytic streptococci were isolated from blood culture and soft tissue after the patient died.

Aged↗

PubMed1999

Effects of mailed advice on stress reduction among employees in Japan: a randomized controlled trial.

We conducted a randomized controlled trial (RCT) to examine the effects of mailed advice on reducing psychological distress, blood pressure, serum lipids, and sick leave of workers employed in a manufacturing plant in Japan. Those who indicated higher psychological distress (defined as having GHQ scores of three or greater) in the baseline questionnaire survey (n = 226) were randomly assigned to an intervention group or a control group. Individualized letters were sent to the subjects of the intervention group, informing them of their stress levels and recommending an improvement in daily habits and other behaviors to reduce stress. Eighty-one and 77 subjects in the intervention and control groups, respectively, responded to the one-year follow-up survey. No significant intervention effect was observed for the GHQ scores, blood pressure, serum lipids, or sick leave (p > 0.05). The intervention effect was marginally significant for changes in regular breakfasts and daily alcohol consumption (p = 0.09). The intervention effect was marginally significant for the GHQ scores among those who initially did not eat breakfast regularly (p = 0.06). The study suggests that only sending mailed advice is not an effective measure for worksite stress reduction. Mailed advice which focuses on a particular subgroup (e.g., those who do not eat breakfast regularly) may be more effective.

Absenteeism↗

PubMed1999

Job stressor-mental health associations in a sample of Japanese working adults: artifacts of positive and negative questions?

To examine whether positive and negative components of mental health were differently related to job stressors and life events, correlational analyses were conducted using data for the GHQ-12 and some scales of the NIOSH Generic Job Stress Questionnaire collected from 765 workers in Japan. Six positive items and six negative items of the GHQ-12 were summed up for positive and negative components of mental health (GHQ-POS, GHQ-NEG). The GHQ-POS was significantly correlated with only positively-oriented job stressors. The GHQ-NEG was significantly correlated with only negatively-oriented job stressors. Most correlations were significantly different between GHQ-POS and GHQ-NEG. This correlation pattern resulted in smaller, but significant, correlations between job stressors and the GHQ-12. These results may reflect "measuring similarity" due to item-wording. Detailed inspection suggested that GHQ-POS and GHQ-NEG, as well as positively- and negatively-oriented job stressors, were not attributable only to positive affectively or negative affectivity, respectively. Work-related events showed higher correlations with all mental health variables than their job stressors' counterparts. For females, mental health variables were seldom correlated with job stressors, but significantly correlated with life events. These results might indicate the superiority of "event-type stress measure" as compared to perceived rating scale in assessing job stressors. Further direction was discussed.

Adolescent↗