Biomedical subjects

T Kitamura

Publications and source records attributed to T Kitamura.

At least 289 records · Page 16Linked to original sources

PubMed1998

Hopelessness in a community population: factorial structure and psychosocial correlates.

The factorial structure of the Beck Hopelessness Scale (BHS; A. T. Beck, A. Weissman, D. Lester, & L. Trexler, 1974) was examined in a nonclinical sample (N = 154) in Japan, and the relationships between dimensions of hopelessness and psychosocial variables were analyzed. A semistructured interview was used, as well as a questionnaire consisting of the BHS, the Eysenck Personality Questionnaire (EPQ; H. J. Eysenck & S. B. Eysenck, 1975), and the Parental Bonding Instrument (PBI; G. Parker, H. Tupling, & L. B. Brown, 1979). A factor analysis with principal components solution after oblimin rotation yielded 2 factors--Doubt About a Hopeful Future (Factor 1) and Belief About a Hopeless Future (Factor 2). Significant, positive correlations were found between Factor 2 and (a) the number of emotional symptoms of depression in a 4-day depressive episode and (b) scores on the Neuroticism subscale of the EPQ. The Factor 1 score was significantly and negatively correlated with the Extraversion subscale of the EPQ and the Paternal Care subscale of the PBI.

Adolescent↗

PubMed1998

Endoscopic and transcutaneous ultrasonographic findings and grey-scale histogram analysis in dogs with caerulein-induced pancreatitis.

Endoscopic ultrasonography (EUS), grey-scale histogram analysis of EUS images, and transcutaneous ultrasonography (TUS) were done in four dogs with caerulein-induced pancreatitis. One other dog was subjected to laparotomy and biopsy specimens were collected for histopathology. By EUS, the pancreatic lesions were first detected at 60 minutes after the start of caerulein infusion. They were detected after 120 to 150 minutes when using TUS. EUS findings included swelling, a more distinct lobular pattern, subcapsular hypoechoic areas, and anechoic stripes through the pancreatic tissue. No marked changes in the histogram analysis was seen until 30 minutes. From 30 to 60 minutes, a decrease in the mean brightness of the pancreatic tissue was observed. These changes in mean brightness reflected histopathological findings showing vacuolization of acinar cells and interstitial oedema of the pancreas. These findings indicated that EUS can detect slight and diffuse changes in pancreatic tissue. Furthermore, grey-scale histogram analysis detects histopathological changes more sensitively than endoscopic ultrasound images.

Animals↗

PubMed1998

Expression of interferon receptor genes (IFNAR1 and IFNAR2 mRNA) in the liver may predict outcome after interferon therapy in patients with chronic genotype 2a or 2b hepatitis C virus infection.

Hepatitis C virus (HCV) genotype 2a or 2b is associated with a favorable outcome after interferon therapy. However, 19% to 33% of patients do not respond to therapy. We investigated whether interferon receptor gene (IFNAR1 and IFNAR2 mRNA) expression in the liver before interferon therapy predicts long-term response to therapy in patients with genotype 2a or 2b HCV infection. Twenty-seven patients who subsequently received interferon-alpha therapy underwent liver biopsies before interferon therapy. Hepatic IFNAR1 and IFNAR2 mRNA were determined using a reverse transcription-polymerase chain reaction assay. Twenty (74%) patients responded to interferon therapy, while the remaining seven (26%) patients were nonresponders. The expression rates of IFNAR1 and IFNAR2 mRNA in the liver were significantly higher in responders than nonresponders (p < 0.01, by chi-square test). The presence of either IFNAR1 or IFNAR2 mRNA predicted complete response to interferon treatment, with a positive predictive value of 100%. Multiple logistic regression analysis showed that IFNAR1 and/or IFNAR2 mRNA expression was the only significant predictor of the effectiveness of IFN therapy (p = 0.0002). We conclude that expression of interferon receptor genes in the liver is a useful index for predicting the long-term efficacy of interferon therapy in patients with chronic genotype 2a or 2b HCV infection.

Adult↗

PubMed1998

Four geographically distinct genotypes of JC virus are prevalent in China and Mongolia: implications for the racial composition of modern China.

JC polyomavirus (JCV) is ubiquitous in humans, persisting in renal tissue and excreting progeny in urine. It has been shown that the genotyping of urinary JCV offers a novel means of tracing human migrations. This approach was used to elucidate the racial composition of modern China. JCV isolates in the Old World were previously classified into nine distinct genotypes. One of them (B1) has a wide domain, encompassing part of Europe and the entirety of Asia. By constructing a neighbour-joining phylogenetic tree, all B1 isolates detected so far were classified into four distinct groups (B1-a to -d), each occupying unique domains in the world. According to this revised classification system of JCV DNAs, four genotypes (CY, SC, B1-a and -b) were found to be prevalent in China and Mongolia (Mongolia was studied instead of Inner Mongolia, which is part of China). There was a remarkable variation in the incidence of genotypes among the sites of sample collection. CY was more frequently detected in Northern China, SC was predominant in Southern China and B1-b was detected only in Mongolia. B1-a was spread throughout China. These data were statistically analysed and the observed regional differences in the incidence of genotypes were found to be significant. It is likely that these differences in JCV distribution in China reflect the intermingling of different population groups that constitute modern China.

Base Sequence↗

PubMed1998

A case of congenital infantile fibrosarcoma of the right hand.

Congenital infantile fibrosarcoma is a rare soft-tissue malignant tumor that usually presents as a mass involving the arm or leg. We report a case of congenital fibrosarcoma on the right hand of a newborn infant. The patient was a 12-day-old male. From the time of delivery, he had a red tumor on his dorsal right hand. The tumor was initially associated with bleeding within a hemangioma and compressed. The course was observed. It appeared that the tumor might be malignant because it increased in size to 10 x 8 x 3 cm, and ulceration and bleeding appeared on the surface after 10 days. A biopsy suggested a fibrosarcoma. The tumor was resected 32 days after birth at the narrow margin in consideration of preservation of function. However, a recurrence was observed under the graft after 2 weeks and another resection was performed. Because the tumor had passed through the interosseous muscle and invaded the palm of the hand, the middle finger, ring finger, and little finger had to be amputated. One year and 7 months postoperatively, no recurrence or metastasis has been observed.

Fibrosarcoma↗

PubMed1998

Social support and pregnancy: I. Factorial structure and psychosocial correlates of perceived social support.

In a questionnaire survey among 1329 first-trimester pregnant women, social support providers were divided by factor analysis into husband, 'premarital network' (parents and friends) and 'postmarital network' (children and mother-in-law), while social support contents were divided into 'given' (emotional, informational and instrumental support) and 'giving' (nurturing opportunity and general confiding). The husband was most frequently nominated by the woman as the support provider in both of these categories. Multiple regression analyses revealed that a husband's poor 'given' support was predicted by the presence of premenstrual irritability, a lower level of the woman's own education, her smoking habits and past experience of pregnancy termination, while a husband's poor 'giving' support was predicted by current older age, smoking habits and past experience of delivery.

Adolescent↗

PubMed1998

Social support and pregnancy: II. Its relationship with depressive symptoms among Japanese women.

In a questionnaire survey among 1329 first-trimester pregnant women, both the husband support measures and unwanted pregnancy ('stressor' agent in pregnancy) showed significant effects on an elevated score of the cognitive disturbance subscale of the Zung's self-rating depression scale (SDS), while only unwanted pregnancies showed an effect on an elevated score of the dysphoric mood subscale of the SDS. However, no interaction was observed between the husband support measures and unwanted pregnancy, therefore the effect of the husband's social support on the cognitive disturbance score was not that of a buffer, but rather a main effector. Finally, multiple regression analyses showed that the dysphoric mood score was preceded by unwanted pregnancy, premenstrual irritability, public self-consciousness, and maternal overprotection; while the cognitive disturbance score was preceded by unwanted pregnancy, husband reduced 'given' and 'giving' support, maternal reduced care and overprotection, paternal reduced care, low annual income, low private self-consciousness, and smoking. These findings suggest that the husband's support for a pregnant woman is effective only in reducing cognitive symptoms, and that different symptomatic constellations have different sets of psychosocial correlates.

Adaptation, Psychological↗

PubMed1998

Psychiatric epidemiology in Japan: towards psychological understanding of the etiology of minor psychiatric disorders.

Epidemiological studies of psychiatric disorders using structured interviews and operational diagnostic criteria in a community population are rare in Japan. In our community study with mainly middle-aged people (Kofu Study), the lifetime prevalence of Major Depressive Episode was 19%. The prevalence was about twice as high in women as in men. The prevalence of Major Depressive Episode showed a tendency to increase as the subjects became younger. No sex difference in the lifetime prevalence of Major Depressive Episode was observed among an adolescent population (Gotemba Study), due to the equally high prevalence of this disorder among male adolescents. The figures were 24% for men and 23% for women. In a follow-up study of pregnant women (Kawasaki Study), risk factors of depression during pregnancy and after childbirth are different and, in some instances, reversed. Therefore, we speculate that the combination of psychological risk factors of the onset of depression may differ from one situation to another. Specificity of the combination of risk factors may be more important than single risk factors in the etiology of mild-form depression.

Adolescent↗

PubMed1998

Childhood parental loss and alcohol dependence among Japanese men: a case-control study. Group for Longitudinal Affective Disorders Study (GLADS).

There have been many studies in the literature examining childhood parental loss as a risk factor for adult psychiatric disorders such as depression, schizophrenia or anxiety disorders. However, with regard to alcohol dependence, only a limited number of such studies exists, and these have reported inconsistent findings. The present paper aims to examine the relationship between early parental loss and subsequent development of alcohol dependence among Japanese men. We directly interviewed 75 men with alcohol dependence (according to DSM-III-R), who were visiting 23 psychiatric hospitals and clinics all over Japan, and 52 healthy controls without any lifetime psychiatric diagnosis, drawn from a general population. When stratified for sex and age, there was no statistically significant difference between the patients and the controls in the rates of maternal or paternal death or separation before the age of 16 years. These findings and the review of the literature suggest that the relationship between childhood parental loss and alcohol dependence is not a straightforward one.

Adult↗

PubMed1998

Cross-cultural comparison of attitudes and opinions on fluorides and fluoridation between Australia and Japan.

This paper reports on two studies exploring similarities and contrasts in knowledge, attitudes and opinions on fluorides and fluoridation of two culturally different population groups. The first study compares the attitudes and opinions of parents of primary (elementary) schoolchildren in Melbourne, Australia, and Yokohama, Japan, and the second study compares the attitudes and opinions of dentists drawn from the same geographic areas. A self-administered questionnaire collected data on 517 parents and 629 dentists. The questionnaires were of similar design and content for both parents and dentists. They included a series of knowledge and attitudinal statements on preventive dentistry and use of fluorides. Attitudinal responses were measured on a 5-point agree-disagree Likert scale. Data were analyzed using both bivariate and multivariate techniques. Australian parents appeared better informed on the benefits of water fluoridation and held more favorable opinions on fluorides and fluoridation than their Japanese counterparts. Similarly, Australian dentists held more positive attitudes toward the use of fluorides and fluoridation than their Japanese peers. Cultural norms and experiences appear to shape parental attitudes, whereas the focus of dental education and dental practice on restorative treatments in Japan appears to be a substantial influence on the attitudes and opinions held by Japanese dentists.

Adolescent↗

PubMed1998

Archetype JC virus efficiently replicates in COS-7 cells, simian cells constitutively expressing simian virus 40 T antigen.

JC polyomavirus (JCV), the causative agent of progressive multifocal leukoencephalopathy (PML), is ubiquitous in humans, infecting children asymptomatically and then persisting in the kidney. Renal JCV is not latent but replicates to excrete progeny in the urine. The renal-urinary JCV DNAs carry the archetype regulatory region that generates various rearranged regulatory regions occurring in JCVs derived from the brains of PML patients. Tissue cultures that support the efficient growth of archetype JCV have not been reported. We studied whether archetype JCV could replicate in COS-7 cells, simian cells transformed with an origin-defective mutant of simian virus 40 (SV40). Efficient JCV replication, as detected by a hemagglutination assay, was observed in cultures transfected with five of the six archetype DNAs. The progeny JCVs could be passaged to fresh COS-7 cells. However, when the parental cells of COS-7 not expressing T antigen were transfected with archetype JCV DNAs, no viral replication was detected, indicating that SV40 T antigen is essential for the growth of JCV in COS-7 cells. The archetype regulatory region was conserved during viral growth in COS-7 cells, although a small proportion of JCV DNAs underwent rearrangements outside the regulatory region. We then attempted to recover archetype JCV from urine by viral culture in COS-7 cells. Efficient JCV production was observed in COS-7 cells infected with five of the six JCV-positive urine samples examined. Thus, COS-7 cells should be of use not only for the production of archetype JCV on a large scale but also for the isolation of archetype JCV from urine.

Aged↗

PubMed1998

Requirement of atypical protein kinase clambda for insulin stimulation of glucose uptake but not for Akt activation in 3T3-L1 adipocytes.

Phosphoinositide (PI) 3-kinase contributes to a wide variety of biological actions, including insulin stimulation of glucose transport in adipocytes. Both Akt (protein kinase B), a serine-threonine kinase with a pleckstrin homology domain, and atypical isoforms of protein kinase C (PKCzeta and PKClambda) have been implicated as downstream effectors of PI 3-kinase. Endogenous or transfected PKClambda in 3T3-L1 adipocytes or CHO cells has now been shown to be activated by insulin in a manner sensitive to inhibitors of PI 3-kinase (wortmannin and a dominant negative mutant of PI 3-kinase). Overexpression of kinase-deficient mutants of PKClambda (lambdaKD or lambdaDeltaNKD), achieved with the use of adenovirus-mediated gene transfer, resulted in inhibition of insulin activation of PKClambda, indicating that these mutants exert dominant negative effects. Insulin-stimulated glucose uptake and translocation of the glucose transporter GLUT4 to the plasma membrane, but not growth hormone- or hyperosmolarity-induced glucose uptake, were inhibited by lambdaKD or lambdaDeltaNKD in a dose-dependent manner. The maximal inhibition of insulin-induced glucose uptake achieved by the dominant negative mutants of PKClambda was approximately 50 to 60%. These mutants did not inhibit insulin-induced activation of Akt. A PKClambda mutant that lacks the pseudosubstrate domain (lambdaDeltaPD) exhibited markedly increased kinase activity relative to that of the wild-type enzyme, and expression of lambdaDeltaPD in quiescent 3T3-L1 adipocytes resulted in the stimulation of glucose uptake and translocation of GLUT4 but not in the activation of Akt. Furthermore, overexpression of an Akt mutant in which the phosphorylation sites targeted by growth factors are replaced by alanine resulted in inhibition of insulin-induced activation of Akt but not of PKClambda. These results suggest that insulin-elicited signals that pass through PI 3-kinase subsequently diverge into at least two independent pathways, an Akt pathway and a PKClambda pathway, and that the latter pathway contributes, at least in part, to insulin stimulation of glucose uptake in 3T3-L1 adipocytes.

3T3 Cells↗

PubMed1998

Requirement for activation of the serine-threonine kinase Akt (protein kinase B) in insulin stimulation of protein synthesis but not of glucose transport.

A wide variety of biological activities including the major metabolic actions of insulin is regulated by phosphatidylinositol (PI) 3-kinase. However, the downstream effectors of the various signaling pathways that emanate from PI 3-kinase remain unclear. Akt (protein kinase B), a serine-threonine kinase with a pleckstrin homology domain, is thought to be one such downstream effector. A mutant Akt (Akt-AA) in which the phosphorylation sites (Thr308 and Ser473) targeted by growth factors are replaced by alanine has now been shown to lack protein kinase activity and, when overexpressed in CHO cells or 3T3-L1 adipocytes with the use of an adenovirus vector, to inhibit insulin-induced activation of endogenous Akt. Akt-AA thus acts in a dominant negative manner in intact cells. Insulin-stimulated protein synthesis, which is sensitive to wortmannin, a pharmacological inhibitor of PI 3-kinase, was abolished by overexpression of Akt-AA without an effect on amino acid transport into the cells, suggesting that Akt is required for insulin-stimulated protein synthesis. Insulin activation of p70 S6 kinase was inhibited by approximately 75% in CHO cells and approximately 30% in 3T3-L1 adipocytes, whereas insulin-induced activation of endogenous Akt was inhibited by 80 to 95%, by expression of Akt-AA. Thus, Akt activity appears to be required, at least in part, for insulin stimulation of p70 S6 kinase. However, insulin-stimulated glucose uptake in both CHO cells and 3T3-L1 adipocytes was not affected by overexpression of Akt-AA, suggesting that Akt is not required for this effect of insulin. These data indicate that Akt acts as a downstream effector in some, but not all, of the signaling pathways downstream of PI 3-kinase.

3T3 Cells↗

PubMed1998

Identification and characterization of a constitutively active STAT5 mutant that promotes cell proliferation.

STAT (signal transducers and activators of transcription) proteins are transcription factors which are activated by phosphorylation on tyrosine residues upon stimulation by cytokines. Seven members of the STAT family are known, including the closely related STAT5A and STAT5B, which are activated by various cytokines. Except for prolactin-dependent beta-casein production in mammary gland cells, the biological consequences of STAT5 activation in various systems are not clear. We applied PCR-driven random mutagenesis and a retrovirus-mediated expression screening system to identify constitutively active forms of STAT5. By this strategy, we have identified a constitutively active STAT5 mutant which has two amino acid substitutions; one is located upstream of the putative DNA binding domain (H299R), and the other is located in the transactivation domain (S711F). The mutant STAT5 was constitutively phosphorylated on tyrosine residues, localized in the nucleus, and was transcriptionally active. Expression of the mutant STAT5 partially dispenses with interleukin 3 (IL-3) as a growth stimulant of IL-3-dependent cell lines. Further analyses of the mutant STAT5 have demonstrated that both of the mutations are required for nuclear localization, efficient transcriptional activation, and induction of IL-3-independent growth of an IL-3-dependent cell line, Ba/F3, and have indicated that a molecular basis for the constitutive activation is the stability of the phosphorylated form of the mutant STAT5.

Animals↗

PubMed1998

Comparison of effects of restraint, cage transportation, anaesthesia and repeated bleeding on plasma glucose levels between mice and rats.

We examined the effects of handling, cage transportation, anaesthesia and repeated bleeding on plasma glucose levels in mice and rats. Plasma glucose was determined using a compact glucose analyser Antsense, which provides a quick and accurate method without the necessity for special specimen preparation. In mice, plasma glucose was significantly elevated after primary handling or cage transportation. Anaesthesia increased plasma glucose levels two-fold, whilst repeated bleeding induced a rapid but transient increase. However, it was found to be possible to sample plasma glucose levels at one-hour intervals without any apparent effect on plasma glucose level as a result of stress from the sampling procedure. In contrast, the same set of procedures i.e. handling, cage transportation and anaesthesia, when performed on rats, seemed to have small or no observable effect on levels of plasma glucose. These results show the importance of the sampling procedure when determining plasma glucose in mice. It is recommended that the procedure which causes the least influence on endogenous glucose levels should be the method of choice and that animals should be acclimatized to the procedure, by appropriate handling, prior to sampling.

Anesthesia↗

PubMed1998

Prevalence of chronic fatigue syndrome in a community population in Japan.

In order to know the prevalence of chronic fatigue syndrome (CFS) in a community population in Japan, we analyzed data from a population-based interview survey. Two cases out of 137 respondents experienced chronic fatigue during a period of nine months, suffered from 50% or more reduction of daily activity due to fatigue and had no other physical or psychiatric diagnosis. Both of the two cases fulfilled the 1994 Centers for Disease Control (CDC) criteria and the British criteria. The point and nine-month prevalence rates of CFS were both 1.5% (95% confidence intervals, 0.4-5.2%). None fulfilled the 1989 CDC criteria for CFS. The prevalence rate of CFS was higher than those in previous studies in the Western countries, suggesting a need for future research on cross-cultural differences in the definition, prevalence and symptomatology of CFS.

Adolescent↗

PubMed1998

Nonasthmatic case of Churg-Strauss syndrome with rapidly progressive glomerulonephritis.

A 61-year-old man developed mononeuritis multiplex accompanied by eosinophilia in 1993. Approximately 3 years later, acute renal dysfunction, a subendocardial tumor, and a high peripheral anti-neutrophil cytoplasmic antibody titer were also detected. Renal biopsy revealed glomerular crescents and interstitial infiltration of eosinophils, so allergic granulomatosis and angiitis was diagnosed. These clinical abnormalities regressed with steroid therapy. He had no history of asthma. This was therefore considered to be an atypical form of Churg-Strauss syndrome with rapidly progressive glomerulonephritis.

Anti-Inflammatory Agents↗

PubMed1998

Japanese psychology students as psychiatric diagnosticians: application of criteria of mood and anxiety disorders to written case vignettes using the RDC and DSM-IV.

It is commonly believed in Japan that only psychiatrists are capable of providing reliable psychiatric diagnosis. The present study, therefore, examined using a case vignette design, how well Japanese psychology students agreed with a psychiatrist on the diagnoses of mood disorders (major depressive disorder and bipolar disorder) and anxiety disorders (pain disorder, obsessive-compulsive disorder, phobic disorder, and generalized anxiety disorder). The results suggest that appropriately trained Japanese psychology students can apply reliably the diagnostic criteria for these disorders, except for generalized anxiety disorder. It appeared that the students did not identify symptoms of restlessness and nervous tension, which may explain the relatively low reliability of the diagnosis for generalized anxiety disorder. The cross-cultural variation in the experience of anxiety is suggested as an explanation. The present study argues that it is feasible that Japanese nonmedical mental health professionals become familiar with the psychiatric diagnoses.

Adult↗