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I Oshima

Publications and source records attributed to I Oshima.

At least 19 recordsLinked to original sources
PubMed2006

Age-related changes in the intramuscular distribution of melanocytes in the Silky fowl.

1. The characteristics of melanocyte distribution in skeletal muscles in the Silky fowl were investigated in association with growth. 2. Pectoralis (PT) and iliotibialis lateralis (ITL) muscles from 1-, 3-, 5-, 10-, 20- and 30-week-old Silky males were weighed and collagen type I was detected in frozen sections immunohistochemically. 3. Melanocytes were observed in the collagen type I-immunopositive endomysium and perimysium in both muscles. 4. Image analysis indicated that the total area occupied by melanocytes in histological sections sharply decreased from 0.61% to 0.16% in PT muscle and from 1.67% to 0.33% in ITL muscle at 1 to 3 weeks, and then gradually decreased. The melanocyte area was larger in ITL muscle than in PT muscle until 10 weeks of age. 5. We concluded that the proportion of intramuscular melanocytes in the Silky fowl differs between types of muscles in the early stages of development, and it decreases with growth.

Aging↗
PubMed2006

Effects of nutritional level on muscle development, histochemical properties of myofibre and collagen architecture in the pectoralis muscle of male broilers.

1. The effects of nutritional level on muscle development, histochemical properties of myofibre and collagen architecture in the pectoralis muscle were evaluated using male broilers of Red Cornish x New Hampshire stock, reared on diets of high nutritional value for up to 80 d (H80d) and low nutritional value for up to 80 d (L80d, same age as H80d) or 95 d (L95d, same body weight as H80d). 2. The total live weight and the weight of pectoralis muscle were lower in L80d than in both H80d and L95d. The muscle weight as a percentage of live weight was 8.7% in L80d, 10.7% in H80d and 11.5% in L95d. 3. Pectoralis muscle was composed only of type IIB myofibres and showed no differences in myofibre type composition among the chicken groups. The largest diameter of type IIB myofibres was observed in L95d, followed by H80d and the smallest in L80d. 4. The total amount of intramuscular collagen did not differ among the chicken groups (1.92 to 1.99 mg/g). Types I and III collagens were immunohistochemically detected in both the perimysia and endomysia. The thin perimysia around the primary myofibre fascicles showed larger width in H80d than L80d and L95d, and also the thick perimysia around the secondary fascicles in H80d than L80d. 5. The collagen structure of the perimysium was most developed in H80d, followed by L95d and on the least in L80d. The development of perimysial collagen fibres could be enhanced by a rapid growth rate of the muscle induced by high nutritional level and depressed by a slow growth rate with low nutritional foods. 6. The endomysial collagen architecture was observed as a felt-like tissue of the fibril bundles with many slits. The thinnest endomysial wall was observed in L80d, followed by H80d and the thickest in L95d. 7. From these results, it was indicated that foods of high nutritional value could enhance growth of the pectoralis muscle of broilers, and this is accompanied by hypertrophy of the type IIB myofibres and development of the perimysial collagen architecture.

Animal Feed↗
PubMed2005

Alterations in follicular dynamics and steroidogenic abilities induced by heat stress during follicular recruitment in goats.

We investigated the changes in follicular dynamics and steroidogenic activity during heat stress in goats. Adult female goats were exposed to heat stress at 36 degrees C and 70% relative humidity for 48 h and then injected with prostaglandin (PG) F2alpha (the time of PGF2alpha injection was designated as 0 h). In experiment 1, every follicle greater than 2 mm in diameter was monitored by ultrasonography to investigate the follicular dynamics, and plasma concentrations of FSH, LH, progesterone, and oestradiol were measured from -48 h to 120 h. In experiment 2, the follicles were recovered from the goats at 48 h, and the concentration of oestradiol, the aromatase activity, and the LH receptor level in the follicles were determined. In control (non-heat-stressed) goats, ovulatory follicles were mainly recruited from -24 h to 0 h, whereas no follicles recruited during that period were ovulated in the heat-stressed goats. The timing of the recruitment of ovulatory follicles was delayed by heat stress by approximately 24 h. The plasma concentration of oestradiol in the heat-stressed goats was significantly lower from 36 to 54 h compared with the controls, although the concentrations of FSH and progesterone did not differ between the treatments. In addition, the concentration of oestradiol, the aromatase activity, and the LH receptor level in the follicles from heat-stressed goats were significantly lower compared with the controls. These results indicate that heat stress during follicular recruitment suppresses subsequent growth to ovulation, accompanied by decreased LH receptor level and oestradiol synthesis activity in the follicles.

Animals↗
PubMed2001

A newly established strain of spontaneously hypertensive rat with a defect of ascorbic acid biosynthesis.

To investigate the effects of ascorbic acid deficiency on the pathogenesis of hypertension and/or its complications, we established a rat strain with both genetic hypertension and a defect of ascorbic acid biosynthesis. The od gene (L-gulono-gamma-lactone oxidase gene) of the ODS (Osteogenic Disorder Shionogi) rat, which is a rat mutant unable to synthesize ascorbic acid, was introduced into spontaneously hypertensive rats (SHR), and a novel congenic strain, SHR-od, was established. SHR-od showed scurvy when fed an ascorbic acid-free diet. Systolic blood pressure of male SHR-od began to increase at 9 weeks of age and reached 190-200 mmHg at 20 weeks of age. In 25-week-old SHR-od, ascorbic acid deficiency when fed an ascorbic acid-free diet for 6 weeks caused a remarkable reduction of blood pressure to lower than 110 mmHg. The wall to lumen ratio of the testicular artery in ascorbic acid-deficient SHR-od was lower than that of the control rats. When rats were fed a diet supplemented with ascorbic acid (300 mg/kg), ascorbic acid concentration in SHR-od was lower in the serum and liver than that in ODS rats. These results indicate that ascorbic acid could be closely related to the development of hypertension in SHR-od. We believe that SHR-od will be a useful model for experimental studies on hypertension and its complications, since all of them suffer from hypertension spontaneously and the level of ascorbic acid deficiency in these rats could be controlled at will both in concentration and duration.

Aging↗
PubMed2000

Administration of melatonin in drinking water promotes the phase advance of light-dark cycle in senescence-accelerated mice, SAMR1 but not SAMP8.

We analyzed effects of aging on behavioral rhythms in the mouse showing senescence acceleration, SAMP8 strains. The free-running rhythms had longer free-running periods (tau) in SAMP8 than in the control strain (SAMR1). Drinking of melatonin promoted the adaptation to advanced LD in SAMR1 but not in SAMP8, although both strains exhibited melatonin MT1 and MT2 receptors. The present results suggest that melatonin promotes the adaptation to advanced LD cycles in normal aging mice.

Adaptation, Physiological↗
PubMed2000

Seasonality of birth in patients with mood disorders in Japan.

BACKGROUND: Findings about seasonality of birth in individuals with mood disorders have been inconsistent. METHODS: Data were collected from the governmental statistics, the Patient Survey in Japan in 1996. The number of patients with mood disorders was 13,969. We obtained information about each patient's date of birth, sex, and diagnosis according to ICD-10. Distributions of monthly birth numbers of patients with mood disorders were compared to those of the general population. RESULTS: Birth excess was observed from winter to early-spring in both sexes, compared to births of the general population. The magnitude of the excess was larger in females than in males. Although the same tendencies were observed in patients with bipolar disorder and depressive disorder, the differences were more marked in females. LIMITATIONS: Insufficient birth data in the general population before 1940 and hospital diagnosis. CONCLUSION: Among Japanese patients with mood disorders, there are excess births from winter to early-spring, compared to the general population. This difference is more marked in females than in males.

Adult↗
PubMed2000

Intra-uterine physical growth in schizophrenia: evidence confirming excess of premature birth.

BACKGROUND: Many studies have suggested a possible aetiological role for obstetric complications in the development of schizophrenia. We focused on prenatal physical growth in schizophrenia, a contentious issue in the literature. METHODS: We compared gestational age at birth, birth weight (BW) and birth head circumference (BHC) between 312 schizophrenics and 517 controls, and between 187 schizophrenics and their matched healthy siblings. Information on obstetric histories was obtained from the Maternal and Child Health Handbooks (i.e. contemporaneous records). RESULTS: Gestational age at birth was significantly earlier in the schizophrenics than in the controls (P = 0.017). Pre-term birth (gestational age of 36 weeks or less) was more common in schizophrenics than in controls (8.0% v. 3.4%, P = 0.005, odds ratio 2.5). Low BW (2500 g or less) was more frequent in schizophrenics than in controls (9.6% v. 4.6%, P = 0.005, odds ratio 2.2). The schizophrenics had significantly lighter BW (P = 0.0003) and tended to have smaller BHC (P = 0.081) compared with controls. However, multiple regression analysis showed that there was no significant difference in BW or BHC between the schizophrenics and controls when gestational age and maternal weight were controlled. There was no significant difference in BW or BHC between schizophrenics and their siblings, although the schizophrenics tended to be born at earlier gestational age than their siblings. CONCLUSIONS: Our results suggest that prematurity at birth is associated with a risk of developing schizophrenia in adulthood. When gestational age and maternal body weight were allowed for, there was no evidence that schizophrenics tend to have lower mean BW or smaller BHC.

Adult↗
PubMed2000

Mood disorders and influenza epidemics in Japan.

The finding that influenza epidemics are associated with an increased risk of adult mood disorder has been controversial. In this study, data were collected from governmental statistics, the Patient Survey in Japan, in 1996. Index years were defined as 1957/58, 1962, and 1965, and comparison years were defined as 2 years before and 2 years after the index year. The subjects were 361 patients with mood disorders who were born in the index years of influenza epidemics. In order to isolate patients exposed to an influenza epidemic during their second prenatal trimester, the months of birth 5 months after the influenza epidemics were defined as risk exposure months. The proportions of patients born during the exposure period in the index years were compared with those of patients born in the corresponding months in the comparison years. The same procedures were conducted for the periods 2 and 8 months after the epidemics. For female inpatients only, the proportion of patients born in the A2 influenza-exposure months in 1965 with second-trimester exposure was smaller than that of patients born in the corresponding months in the comparison years; the same phenomenon was observed for third-trimester exposure in 1957-58. However, no differences were observed in other comparisons. These findings suggest that prenatal exposure to influenza might decrease the risk for adult mood disorders in females. However, whether there is a causal relationship is still unproven.

Adult↗
PubMed2000

[A study of the guideline of case management for persons with mental disorders analyzed with fidelity index. The conditions of effective implementation].

OBJECTIVE: The present study examines the condition of effective case management based on the guideline of case management for persons with mental disorders. METHODS: A total of 295 clients were admitted to a case management trial for about 2 months. A fidelity index of program implementation and outcome measures of case management were developed. The relationship between implementation of critical program components measured by fidelity index, and outcome was analyzed. RESULTS: Fidelity Index was significantly correlated with outcome measures of clients, staffs and the care system. Effective but not-easily-feasible elements of program were having case-conference, application, of informal support and development of services. CONCLUSION: It is necessary to facilitate application of informal support with liaison with public health nurses, to standardize case-conference and to place development of care services in the core of programs for ensuring effective implementation of case management for persons with mental disorders in Japan.

Adult↗
PubMed2000

[The effects of family interventions for the patients with mental illness in health centers focusing on the relatives' own life].

Recently, the burden on relatives of patients with mental illness has been recognized and the need for support to reduce such burden has increased. In Japan, family interventions have been conducted at Health Centers, most of them focusing on the family functioning as a caregiver. However, it is also important to focus on the relative's functioning to live their own life in family interventions. In this study, we executed a program focusing on relatives' life and health, and investigated the effects of this program on both family functioning. Family intervention programs were conducted at 10 Health Centers including both urban and rural areas in Japan. A total of 102 relatives responded to the self-administered questionnaire at the first and the last session of the family interventions. We measured functioning as a caregiver using the Support for the Disabled Score and Rejective Feeling Score, and functioning to live their own life by GHQ Distress in Daily life Score, Perceived Health Condition Score and Life Satisfaction Score. During interventions, GHQ score and Distress in Daily Life score which indicate the disfunction in living their own life decreased, and Support score increased in all sample. In the short-term illness group (n = 35), only the GHQ score decreased, while in long-term illness group (n = 44) Distress score decreased and Support Score increased. The intervention program focusing on relatives' life and health may improve both family functionings to give adequate care for patients, and to live their own daily life. Results suggested that the short-term illness group requires more intensive and personal advices, and the long-term illness group need continuous support focusing on the relative's own life. Expected roles of Health Centers are cooperation with family interventions provided at hospitals and coordination of the services in the community, as well as providing family interventions in terms of relatives' life.

Aged↗
PubMed1999

The FLS mouse: a new inbred strain with spontaneous fatty liver.

BACKGROUND AND PURPOSE: A new strain of mouse, named FLS (fatty liver Shionogi), which develops spontaneous fatty liver without obesity, was established by inbreeding. Morphologic, physiologic, and genetic characterization of the strain was done. METHODS: Characteristics of male FLS mice were compared with those of the sister strain, dd Shionogi (DS), which does not develop spontaneous fatty liver. A genetic cross experiment was performed by mating FLS with C3H/He/Shi mice. RESULTS: The hepatocytes of neonatal FLS mice contained fine lipid droplets throughout the lobules, and large lipid droplets appeared as mice aged. Liver triglyceride concentrations of FLS mice were fivefold higher than those of DS mice, but serum lipid concentrations and the lipoprotein profile did not indicate abnormalities. Higher plasma aspartate transaminase and alanine transaminase activities in FLS, compared with DS mice, suggested hepatocellular lesions. The genetic cross experiment suggested that the fatty liver formation is a complex polygenic trait. CONCLUSION: The FLS mice develop a progressive hepatic steatosis without obesity and diabetes. The FLS mouse might be a good model for investigating hepatic disorders accompanied by fatty liver unrelated to alcoholism or obesity.

Adipose Tissue↗
PubMed1998

Nitroblue tetrazolium reduction of neutrophils in heat stressed goats is not influenced by selenium and vitamin E injection.

Experiment was designed to determine whether heat stress suppresses neutrophil function and injections of selenium and vitamin E prior to heat stress prevent suppression of neutrophil function in goats. Twelve female goats were divided into 2 groups of 6 each and were kept at 25 degrees C. Goats in the treatment group were injected intramuscularly with 0.1 mg/kg of selenium and 2.72 IU/kg of vitamin E at 8 and 1 day prior to the initiation of heat stress. The other group was kept as control. All goats were exposed to hot environment at 38 degrees C from day 0 through 8. Decreased tendency in plasma cortisol concentrations and temporary increase in plasma glucose concentrations were shown in both groups. In the control group, plasma selenium concentration gradually increased and alpha-tocopherol concentration decreased during the first 2 days. After the second injection with selenium and vitamin E, plasma selenium and alpha-tocopherol concentration significantly increased and remained higher than those in the control group. Whole blood glutathione peroxidase (GSH-Px) activity in the treatment group tended to be greater than that in the control group, but no significant difference was observed between 2 groups. The nitroblue tetrazolium (NBT) reduction by activated neutrophils significantly decreased on day 6 in the control group but not in the treatment group. The NBT reduction by resting neutrophils significantly decreased in both groups. These data suggest that heat stress depresses neutrophil function, and selenium and vitamin E injection prior to heat stress has no apparent effect on neutrophil function during the stress.

Animals↗