Cross-Sectional Inverse Association of Regular Soy Intake with Insulin Resistance in Japanese Elderly.

Levels of isoflavones, biomarkers of soy intake, in 24-hour urine (24U) were inversely related to coronary heart disease (CHD) mortality in the World Health Organization's Cardiovascular Disease and Alimentary Comparison Study. Considering 24 U isoflavone levels were highest and CHD mortality was lowest in the Japanese, who maintained the world's longest life expectancy, the association of regular soy intake with cardiometabolic risk was investigated in Japanese adults (20-49 years old) and elderly (50-79 years old). In multivariate analysis adjusted for age, sex, and drug treatments, mean 24 U isoflavone excretion was significantly inversely associated with insulin resistance in the elderly and significantly associated with blood folate and potassium in the elderly, but also positively associated with 24 U salt in the elderly. These findings indicate that low-salt soy should be recommended to improve glucose metabolism in elderly Japanese.

Long-term effects of hepatocyte growth factor gene therapy in rat myocardial infarct model.

We investigated the long-term effects of human hepatocyte growth factor (HGF) gene therapy in a rat myocardial infarct model. Treatment adenovirus coexpressing the HGF therapeutic gene and the human sodium/iodide symporter (NIS) reporter gene or control adenovirus expressing the NIS gene alone were injected directly into the infarct border zone immediately after permanent coronary ligation in rats (n=6 each). A uniform disease state was confirmed in the acute phase in terms of impaired left ventricular (LV) function by cine magnetic resonance imaging (MRI), large infarct extent by (99m)Tc-tetrofosmin single-photon emission computed tomography (SPECT) and successful gene transfer and expression by (99m)TcO(4)(-) SPECT. After a 10-week follow-up, repeated cine MRI demonstrated no significant difference in the LV ejection fraction between the time points or groups, but a significantly increased end-diastolic volume from the acute to the chronic phase without a significant difference between the groups. Capillary density was significantly higher in the treatment group, whereas arteriole density remained unchanged. Two-photon excitation fluorescence microscopy revealed extremely thin capillaries (2-5 µm), and their irregular networks increased in the infarct border zone of the treated myocardium. Our results indicated that single HGF gene therapy alone induced an immature and irregular microvasculature.

Asef2 and Neurabin2 cooperatively regulate actin cytoskeletal organization and are involved in HGF-induced cell migration.

The tumor suppressor adenomatous polyposis coli (APC) is mutated in sporadic and familial colorectal tumors. APC interacts with the Rac1- and Cdc42-specific guanine-nucleotide exchange factors (GEF), Asef and Asef2, which contain an APC-binding region (ABR) in addition to Dbl homology, Pleckstrin homology (PH) and Src homology 3 (SH3) domains. APC stimulates the GEF activity of Asef and Asef2, and thereby regulates cell adhesion and migration. Here we show that Asef2, but not Asef, interacts with Neurabin2/Spinophilin, a scaffold protein that binds to Filamentous actin (F-actin). In response to hepatocyte growth factor (HGF) treatment of HeLa cells, Asef2, Neurabin2 and APC were induced to accumulate and colocalize in lamellipodia and membrane ruffles. Neurabin2 did not affect the GEF activity of Asef2. RNA interference experiments showed that Asef2, Neurabin2 and APC are involved in HGF-induced cell migration. Furthermore, knockdown of Neurabin2 resulted in the suppression of Asef2-induced filopodia formation. These results suggest that Asef2, Neurabin2 and APC cooperatively regulate actin cytoskeletal organization and are required for HGF-induced cell migration.

Expression of pentraxin 3 (PTX3) in human atherosclerotic lesions.

Pentraxin 3 (PTX3) and C-reactive protein (CRP) are members of the pentraxin superfamily. PTX3 expression is induced in response to inflammatory signals, and is produced at sites of inflammation by several types of cell, primarily monocytes/macrophages, dendritic cells (DCs), endothelial cells, smooth muscle cells (SMCs), and fibroblasts, but is not produced by hepatocytes, which are a major source of CRP. The aim of our study was to investigate the expression pattern of PTX3 in human atherosclerotic lesions using a novel monoclonal antibody against PTX3. We examined coronary arterial thrombi containing an atherosclerotic plaque component removed from patients with acute myocardial infarction and human aortic tissues with various degrees of atherosclerosis sampled from autopsy cases. Immunohistochemical study of paraffin and frozen sections indicated that macrophages, mainly foam cells, expressed PTX3 in advanced atherosclerotic lesions. Interestingly, we also clearly observed PTX3-positive neutrophils infiltrating into atherosclerotic plaques, suggesting that PTX3 derived from neutrophils as well as macrophages plays an important role in atherogenesis.

Identification and characterization of Asef2, a guanine-nucleotide exchange factor specific for Rac1 and Cdc42.

The tumor suppressor adenomatous polyposis coli (APC) is mutated in sporadic and familial colorectal tumors. APC interacts with the Rac1-specific guanine-nucleotide exchange factor (GEF) Asef, which contains an APC-binding region (ABR) in addition to Dbl homology (DH), Pleckstrin (PH) and Src homology 3 (SH3) domains. APC stimulates the GEF activity of Asef, and thereby regulates cell adhesion and migration. Here, we have identified a second Asef, termed Asef2, that shows significant structural and functional similarities to Asef. We found that both the N-terminal ABR and SH3 domains of Asef2 are responsible for its interaction with APC. When expressed in HeLa cells, a mutant Asef2 lacking the ABR and SH3 domains, Asef2-DeltaABR/SH3, induced increases in the levels of the active forms of Rac1 and Cdc42. Full-length Asef2 also showed this activity when co-transfected with truncated mutant APC expressed in colorectal tumor cells. Consistent with this, either Asef2-DeltaABR/SH3 or Asef2 plus truncated mutant APC stimulated lamellipodia formation in MDCK cells and filopodia formation in HeLa cells. Furthermore, RNA interference experiments showed that Asef2 is required for migration of colorectal tumor cells expressing truncated APC. These results suggest that similar to Asef, Asef2 plays an important role in cell migration, and that Asef2 activated by truncated mutant APC is required for aberrant migration of colorectal tumor cells.

Brain oxidation is an initial process in sleep induction.

CNS activity is generally coupled to the vigilance state, being primarily active during wakefulness and primarily inactive during deep sleep. During periods of high neuronal activity, a significant volume of oxygen is used to maintain neuronal membrane potentials, which subsequently produces cytotoxic reactive oxygen species (ROS). Glutathione, a major endogenous antioxidant, is an important factor protecting against ROS-mediated neuronal degeneration. Glutathione has also been proposed to be a sleep-promoting substance, yet the relationship between sleep and cerebral oxidation remains unclear. Here we report that i.c.v. infusion of the organic peroxide t-butyl-hydroperoxide at a concentration below that triggering neurodegeneration (0.1 micromol/100 microl/10 h) promotes sleep in rats. Also, microinjection (2 nmol, 2 microl) or microdialysis (100 microM, 20 min) of t-butyl-hydroperoxide into the preoptic/anterior hypothalamus (POAH) induces the release of the sleep-inducing neuromodulators, nitric oxide and adenosine, without causing neurodegeneration. Nitric oxide and adenosine release was inhibited by co-dialysis of the N-methyl-D-aspartate receptor antagonist, d(-)-2-amino-5-phosphonopentanoic acid (D-AP5; 1 mM), suggesting that glutamate-induced neuronal excitation mediates the peroxide-induced release of nitric oxide and adenosine. Indeed, Ca2+ release from mitochondria and delayed-onset Ca2+ influx via N-methyl-D-aspartate receptors was visualized during peroxide exposure using Ca2+ indicator proteins (YC-2.1 and mitochondrial-targeted Pericam) expressed in organotypic cultures of the POAH. In the in vitro models, t-butyl-hydroperoxide (50 microM) causes dendritic swelling followed by the intracellular Ca2+ mobilization, and D-AP5 (100 microM) or glutathione (500 microM) inhibited t-butyl-hydroperoxide-induced intracellular Ca2+ mobilization and protected POAH neurons from oxidative stress. These data suggest that low-level subcortical oxidation under the control of an antioxidant system may trigger sleep via the Ca(2+)-dependent release of sleep-inducing neuromodulators in the POAH, and thus we propose that a moderate increase of ROS during wakefulness in the neuronal circuits regulating sleep may be an initial trigger in sleep induction.

Can foods with added soya-protein or fish-oil reduce risk factors for coronary disease? A factorial randomised controlled trial.

BACKGROUND AND AIMS: To develop functional foods which are capable of reducing key risk factors for coronary heart disease in an at risk population. The specific hypothesis tested here was that providing bread, cracker biscuits and snack bars fortified with DHA (long-chain omega 3) and soya-protein would havd a positive impact on cholesterol and blood pressure. METHODS AND RESULTS: A pragmatic, double-blind, factorial placebo-controlled randomised trial recruiting 213 middle-aged men and women with untreated elevated total cholesterol or blood pressure. The factors examined were the effect of giving supplies of bread, cereal bars and cracker biscuits fortified with 2 g fish oils (DHA, 22: 6n-3), or 25 g soya-protein (containing 50 mg of isoflavonoids) for five weeks. Primary and secondary outcomes included total, low-density and high-density cholesterol (HDL-C), and systolic and diastolic blood pressure. Compliance was assessed using biomarkers and food intake histories. DHA enriched foods increased HDL-C by 6.0% (95% CI 2.5%, 9.6%) but had no effect on total or low-density cholesterol or blood pressure. Overall, soya-protein did not influence any of the outcomes assessed. However, in women only, soya-protein increased systolic blood pressure by 5.9% (95% CI 1.73, 9.9%). CONCLUSIONS: Adding DHA (fish-oils) to staple foods might supplement existing methods to help reduce CVD morbidity and mortality. However, these findings highlight the importance of ensuring that functional foods do not present any harms to particular subgroups within a general population, if they are to be made freely available to consumers. This latter point requires further attention by the research community in relation to soya-protein.

The sulphydryl reagent, N-ethylmaleimide, disrupts sleep and blocks A1 adenosine receptor-mediated inhibition of intracellular calcium signaling in the in vitro ventromedial preoptic nucleus.

To explore the neuronal signaling mechanisms underlying sleep regulation in the rat, the present study examined continuous intra-third ventricle infusion of N-ethylmaleimide (NEM), a sulphydryl reagent that inhibits G(i/o) protein-coupled receptor-mediated signaling pathways. The diurnal infusion of NEM (0.01-10 micromol/10 h) dose-dependently inhibited both non-rapid eye movement sleep and rapid eye movement sleep. A maximal dose of NEM (10 micromol/10 h) dramatically inhibited day-time sleep (-57% for non-rapid eye movement sleep and -89% for rapid eye movement sleep) with a compensatory increase of sleep during the subsequent night-time (+33% for non-rapid eye movement sleep and +259% for rapid eye movement sleep). The day-time brain temperature was also increased by NEM, demonstrating effects of NEM on both sleep and body temperature levels. Immunostaining of the rat hypothalamus with a monoclonal antibody against the A1 adenosine receptor (A1R) was used to explore the distribution of a sleep-related G(i/o) protein-coupled receptor. Robust A1R-like immunoreactivity was found in the ventromedial preoptic nucleus and the supraoptic nucleus. Fura-2-based Ca(2+) imaging analysis of acute hypothalamic slices further demonstrated that the A1R agonist N(6)-cyclopentyladenosine (CPA; 200 nM) inhibited spontaneous Ca(2+) oscillations and high potassium (80 mM)-induced Ca(2+) flux in the ventromedial preoptic nucleus, while NEM (100-300 microM) and an A1R antagonist 8-cyclopentyl-dipropylxanthine (300 nM) blocked the CPA actions and increased the high potassium-induced Ca(2+) flux. From these results we suggest that NEM-sensitive G protein-coupled receptor(s) may play an important role in the regulation of sleep and body temperature in the rat and one possible mechanism is an A1R-mediated regulation of intracellular Ca(2+) concentrations in the ventromedial preoptic nucleus.

Leisure-time physical activity and other factors in relation to blood pressure in Japanese-Americans in Hawaii, USA.

To examine physical activity at work and during leisure-time as well as other factors related to blood pressure (BP) in Japanese-Americans living in Hilo, Hawaii, USA, we performed a population-based cross-sectional study with a sample of 238 participants aged 42-64 years old. This survey was carried out between 19 February and 1 March 2000 in Hilo. All participants were invited to Hilo Medical Center for a free physical examination and experimental tests including an examination of blood and urine samples. A self-administered health questionnaire was used that included items related to demographics, smoking, alcohol consumption, and habitual physical activity at work and during leisure-time. A summary score of physical activity (PA) was calculated. BP was measured using an automated BP measurement system (Khi machine, VINE Co., Ltd., Kyoto, Japan). The results showed the following. 1) Mean (SD) PA scores at work (WPA) and during leisure-time (LTPA) were 2.9 (0.5) and 2.5 (0.5) in men, and 3.0 (0.5) and 2.4 (0.3) in women, respectively; 2) Pearson correlation analyses (adjustment for age) indicated that WPA and LTPA in men show significant negative associations with SBP and DBP (p<0.05 and p<0.01), while LTPA shows significant negative associations with SBP and DBP in women (p<0.05 and p<0.01). After further adjustment for education, occupation, smoking, and alcohol consumption status, LTPA continued to show significant and negative associations with both SBP and DBP in men (p<0.01) and with DBP alone in women (p <0.01). 3) Hypertensive subjects had significantly lower mean LTPA scores than normotensive men (2.39 vs. 2.61, p<0.05) and women (2.32 vs. 2.45, p<0.05). 4) Body mass index and the ratio of sodium to potassium excretion showed significant and positive associations with SBP and DBP in multiple linear regression analyses. In conclusion, the results further emphasize that the health benefits of LTPA, control of body weight, and reduction in salt intake should continually receive strong attention in population-based high BP control.

Adjuvant-induced improvement of glucose intolerance in type 2 diabetic KK-Ay mice through interleukin-1 and tumor necrosis factor-alpha.

We reported that administration of complete Freund's adjuvant (CFA) improved glucose tolerance test (GTT) results in obese diabetic KK-Ay mice. In this study, we investigated its mechanism. An injection with CFA remarkably improved GTT for more than a week in KK-Ay mice, although insulin response was not changed compared with saline controls. The hypoglycemic effect of insulin was significantly, but partially, potentiated in the CFA-treated mice compared with the controls, suggesting that CFA stimulated insulin-mediated and non-insulin-mediated glucose disposal. Improvement in the GTT with CFA was partially transferable to nontreated mice by peritoneal exudative cells, but not spleen or lymph node cells. Pretreatment with anti-interleukin (IL)-1 alpha and -1 beta antibodies or anti-tumor necrosis factor (TNF)-alpha antibody significantly abrogated the improvement in the GTT with CFA. The results indicate that CFA-induced improvement in glucose intolerance in KK-Ay mice was mediated at least by IL-1 and TNF-alpha.

Assessment of in vivo oxidative stress in hypertensive rats and hypertensive subjects in Tanzania, Africa.

Oxidative stress has been reported to be involved in not only cardiovascular diseases but in hypertension, which is a major risk for cardiovascular diseases. Urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG) has been recognized as a sensitive biomarker of oxidative DNA damage and also of oxidative stress. In the present study, we assessed the oxidative stress in human subjects with hypertension and in hypertensive rats. In stroke-prone spontaneously hypertensive rats at the age of 14 weeks, the excretion of urinary 8-OHdG was significantly (p < 0.05) increased compared with that in age-matched normotensive Wistar-Kyoto rats. Next, we investigated the relationship between oxidative DNA damage and cardiovascular risk factors among Tanzanians aged 46-58 years in a population study carried out in 1998 in at Dar es Salaam, Tanzania, according to the WHO-CARDIAC Study Protocol. Sixty subjects (male/female, 28/32) were selected by SPSS Base 8.0 from those who completed a 24-h urine collection. The 24-h urinary 8-OHdG of the hypertensive subjects (SBP > or =140 mmHg and/or DBP > or =90 mmHg) was significantly (p < 0.05) higher than that of the normotensive subjects (SBP <140 mmHg and DBP <90 mmHg) after adjusting for age and gender (Hypertensives: 17.31 +/- 2.0 ng/mg creatinine, n=38; Normotensives: 10.10 +/- 2.64 ng/mg creatinine, n=22). Oxidative stress was thought to be involved in hypertensive subjects and in hypertensive rats.

Continuous exposure to dim illumination uncouples temporal patterns of sleep, body temperature, locomotion and drinking behavior in the rat.

Dissociable circadian rhythms of sleep and body temperature in primates are thought to be regulated by independent oscillators whereas the uncoupling of circadian rhythms has not been well described in other mammals. Therefore, we made simultaneous recordings of non-rapid-eye-movement-sleep (NREMS), rapid-eye-movement-sleep (REMS), brain temperature, intraperitoneal temperature, locomotion and drinking activity under light-dark (LD) and continuous dim illumination (dim LL) and analyzed their interrelations. The rhythmic patterns of body temperature, locomotion and drinking were modified on the 12th circadian day of dim LL, while the mean body temperature as well as mean occurrence of drinking and locomotor activities did not change significantly. In contrast, dim LL exposure significantly increased the total time spent in NREMS during the resting phase of dim LL and increased REMS episodes during the active phase of dim LL. The diverse effects of dim LL exposure on the recorded phenomena suggest that temporal patterns of sleep were the most sensitive to perturbations of lighting and that differential oscillatory mechanisms may regulate sleep and other circadian rhythms in the rat.

Increased oxidative DNA damage in stroke-prone spontaneously hypertensive rats.

1. The amount of urinary 8-hydroxy-2'-deoxyguanosine (8-OHdG), a biomarker of the total systemic oxidative stress in vivo, in stroke-prone spontaneously hypertensive rats (SHRSP) was not different from that in control normotensive Wistar-Kyoto (WKY) rats at 6 weeks of age, but became higher than control values after the development of severe hypertension at 14-17 weeks of age. 2. The amount of urinary 8-OHdG was not significantly different between SHRSP treated with anti-hypertensive agents and those not treated at 14 weeks of age. 3. Stroke-prone spontaneously hypertensive rats were exposed to DNA damage by oxidative stress at the early stage when they developed severe hypertension, but this increase in DNA damage was not the secondary effect of hypertension.

Expression of mucin 1 (MUC1) in esophageal squamous-cell carcinoma: its relationship with prognosis.

Using 2 anti-mucin 1 (MUC1) monoclonal antibodies (MAbs), DF3 and BCP8, we examined MUC1 expression immunohistochemically in 192 esophageal squamous-cell carcinomas (SCCs). In normal squamous epithelium of the esophagus, DF3 was not expressed, but BCP8 was expressed on the cell membrane, mainly in the surface layer. In esophageal SCCs, DF3 and BCP8 were expressed mainly on the cell membrane of SCC cells, but also in the cytoplasm in several cases. To analyze the correlation of MUC1 expression and the prognosis of the patients, the 192 cases were divided into 2 groups: high-expression group (HEG, > 50% of the neoplastic cells stained) and low-expression group (LEG, < 50% of neoplastic cells stained). DF3-HEG (24 patients) showed a significantly poorer survival rate than DF3-LEG (168 patients), whereas there was no significant difference in survival between BCP8-HEG (43 patients) and BCP8-LEG (149 patients). Also, in the analysis of 162 patients with advanced stage (submucosal or deeper invasion) to exclude the influence of low expression of DF3 and BCP8 in 30 patients with early stage (up to the level of muscularis mucosae), DF3-HEG (24 patients) showed significantly poorer survival than DF3-LEG (138 patients), whereas there was no significant difference in survival between BCP8-HEG (42 patients) and BCP8-LEG (120 patients). The results of our study on esophageal SCC suggest that the expression of sialyl oligosaccharides detected by DF3 is related to poor prognosis.

Gold alloys for resin bonding including small amount base metals--structural changes of alloy surface by the high-temperature oxidation.

To achieve durable bonding with adhesive resin, the surface roughness and the kinds of oxides, respectively to increase mechanical retention to enhance the chemical affinity of adhesive monomer with the gold alloy, were regulated by high-temperature oxidation together with the addition of small amounts of base metals. Alloys containing 2 mass% of Ni, In, or Cr with Cu were oxidized at 800 degrees C for 20 min in air, pickled in thioglycolic acid, and subsequently oxidized at 500 degrees C for 10 min in air. The morphology of the internal oxidation zone changed markedly according to the added base metals. Although the internal oxide particle composed of only Cu2O was removed by pickling, NiO, In2O3, and chromium oxides could not removed and remained on the alloy surface. The surface roughness was increased by addition of Ni, In, or Cr. Applying the present method can control the roughness and chemical states on a gold alloy surface to increase its adhesive ability with adhesive resins.

Inhibitory effect of troglitazone on diabetic neuropathy in streptozotocin-induced diabetic rats.

Free-radical scavengers and inhibitors of tumour necrosis factor-alpha (TNF-alpha) such as N-acetylcysteine and pentoxifylline have been shown to inhibit the development of peripheral neuropathy in streptozotocin(STZ)-induced diabetic rats. In this study we examined the effect of troglitazone, an anti-diabetic thiazolidinedione, on diabetic neuropathy, since it also is a free-radical scavenger and a TNF-alpha inhibitor. Rats were fed powder chow mixed with troglitazone at 0.5% and 0.125% ad libitum. Although blood glucose concentrations were remarkably higher and body weight lower in diabetic than in nondiabetic rats, troglitazone had no effect on these throughout the 24-week experiment. Serum lipoperoxide concentrations, tibial nerve lipoperoxide content and serum TNF-alpha activity induced by lipopolysaccharide was increased in diabetic rats, but inhibited in troglitazone-treated rats. Motor nerve conduction velocity (MNCV) of the tibial nerve slowed in diabetic rats, compared with that in nondiabetic rats. On the other hand, the slowed MNCV was (p < 0.05-0.01) inhibited after weeks 12 and 16 of the experiment in diabetic rats treated with high and low doses of troglitazone, respectively. Morphometric analysis showed that troglitazone suppressed the decrease of the myelinated fibre area (p < 0.05), axon/myelin ratio (p < 0.01) and fascicular area (p < 0.05) and suppressed the increase of myelinated fibre density (p < 0.001) in diabetic rats. These results indicate that troglitazone has a beneficial effect on peripheral neuropathy in STZ-induced diabetic rats irrespective of blood glucose concentrations.

Sociocultural influences and care of dying children in Japan and the United States.

Caring for dying children and their families is one of the most difficult and challenging aspects of professional nursing. An analysis of cultural influences provides insight into the diverse worldviews held by people in Japan and the United States that affect nursing care of dying children. Selected cultural aspects that influence behaviors in Japanese and American cultures are reviewed in this article. Characteristics of support models for dying children and their families established in Western cultures are discussed. This cross-cultural review of prevalent sociocultural influences on the care of dying children and their families in Japan and the United States clearly demonstrates numerous contrasts and parallels.

Gliclazide inhibits diabetic neuropathy irrespective of blood glucose levels in streptozotocin-induced diabetic rats.

N-acetylcysteine and pentoxifylline, free radical scavengers and inhibitors of tumor necrosis factor-alpha (TNF-alpha) production, inhibit the development of peripheral neuropathy in streptozotocin (STZ)-induced diabetic rats. This study was designed to elucidate the effect of gliclazide, an oral hypoglycemic sulfonylurea, on diabetic neuropathy, because it has been indicated to be a free radical scavenger and TNF-alpha inhibitor. Rats were fed with powder chow mixed with gliclazide or glibenclamide as a control ad libitum. Blood glucose levels and body weight were remarkably higher and lower in diabetic than in nondiabetic rats, respectively, while gliclazide and glibenclamide had no effect on these in both diabetic and nondiabetic rats throughout a 24-week experiment. Serum lipoperoxide levels and lipopolysaccharide (LPS)-induced serum TNF-alpha activities were significantly increased in diabetic rats, whereas these were significantly inhibited in gliclazide-treated rats. Motor nerve conduction velocity (MNCV) of the tibial nerve significantly slowed in diabetic rats compared with nondiabetic rats. On the other hand, the slowed MNCV was significantly inhibited in gliclazide-treated diabetic rats after 16 experimental weeks. Morphometric analysis showed that gliclazide prevented decreased myelinated fiber area (P < .05), increased fiber density (P < .001), and decreased axon/myelin ratio (P < .05) in diabetic rats. Glibenclamide treatment did not affect serum lipoperoxide, TNF-alpha, MNCV, or nerve morphology in this experiment. These results indicate that gliclazide has a beneficial effect on peripheral neuropathy in STZ-induced diabetic rats, irrespective of blood glucose levels.

Methylcobalamin amplifies melatonin-induced circadian phase shifts by facilitation of melatonin synthesis in the rat pineal gland.

Effects of methylcobalamin (methyl-B12), a putative drug for treating human circadian rhythm disorders, on the melatonin-induced circadian phase shifts were examined in the rat. An intraperitoneal injection of 1-100 microg/kg melatonin 2-h before the activity onset time (CT 10) induced phase advances of free-running activity rhythms in a dose-dependent manner (ED50=1.3 microg/kg). Injection of methyl-B12 (500 microg/kg) prior to melatonin (1 microg/kg) injection induced larger phase advances than saline preinjected controls, while the injection of methyl-B12 in combination with saline did not induce a phase advance. These results indicate amplification of melatonin-induced phase advances by methyl-B12. Pinealectomy abolished the phase alternating effect of methyl-B12, suggesting a site of action within the pineal gland. In fact, methyl-B12 significantly increased the content of melatonin in the pineal collected 2-h after activity onset (CT 14). In contrast, no difference in melatonin content was found at CT 10, indicating that the effect of methyl-B12 may be gated after the activity onset time when endogenous melatonin synthesis is known to increase. These results suggest that methyl-B12 amplifies melatonin-induced phase advances via an increase in melatonin synthesis during the early subjective night at a point downstream from the clock regulation.

Value of glutathione S-transferase pi and the oncogene products c-Jun, c-Fos, c-H-Ras, and c-Myc as a prognostic indicator in endometrial carcinomas.

OBJECTIVE: To examine the relationship between the expressions of glutathione S-transferase pi (GST-pi) and four oncogene products, c-Jun, c-Fos, c-H-Ras, and c-Myc, and clinicopathological prognostic factors and patients' prognosis in endometrial carcinomas, and to assess their prognostic value in endometrial carcinomas. METHODS: Specimens of endometrial carcinoma obtained from 63 patients were investigated immunohistochemically using respective specific antibodies. RESULTS: The overall positive rates in 63 carcinoma specimens were 34.9% for GST-pi, 44.4% for c-Jun, 34.9% for c-Fos, 47.6% for c-H-Ras, and 54.0% for c-Myc. Multivariate analysis revealed that GST-pi expression correlated independently with paraaortic lymph node (PAN) metastasis, and c-Jun expression was independently related to pelvic lymph node (PLN) and PAN metastasis. The prognosis of patients with a GST-pi-positive tumor was significantly poorer than that of those with a GST-pi-negative tumor (P < 0.05). The patients with c-Jun-positive tumor also had a significantly worse prognosis than those with c-Jun-negative tumor (P < 0.05). No significant relationship between the expressions of the remaining three oncogene products, c-Fos, c-H-Ras, and c-Myc, and the examined prognostic factors and clinical outcome was apparent. CONCLUSION: These results suggest that the expressions of GST-pi and c-Jun may reflect the metastatic potential of endometrial carcinomas and that their expressions of endometrial carcinoma may be useful as a prognostic indicator for predictive testing.