The ventromedial hypothalamic nucleus is not essential for the prefeeding corticosterone peak in rats under restricted daily feeding

The role of the ventromedial hypothalamic nucleus (VMH) in the generation of the prefeeding corticosterone peak was examined in rats under restricted daily feeding, under which daily meal supply was restricted to a fixed time in the early light period. Rats were lesioned in the VMH bilaterally and subjected to restricted daily feeding during two different post-operative phases and with two different durations of food presentation. A restricted feeding with free access to meal for 4 hr was imposed on the VMH-lesioned rats from 2 to 4 weeks after the lesion, when the daily food intake increased significantly (dynamic phase). The restricted feeding induced the prefeeding hormone peak in sham operated rats, but failed to develop it in the VMH-lesioned rats. On the other hand, the hormone peak appeared in the VMH-lesioned rats subjected to the feeding schedule from 8 to 10 weeks after the lesion, when the daily food intake was not different from the control (static phase). Moreover, the VMH-lesioned rats showed the hormone peak even in the dynamic phase when the access to meal was shortened to 1 hr. These results indicate that the VMH is not essential for the generation of the prefeeding corticosterone peak under restricted daily feeding, and suggest that a special metabolic state observed during the dynamic phase of VMH lesion prevents the development of the feeding-associated oscillation or its expression upon plasma corticosterone level.     

MCM2 and Ki-67 expression in human lung adenocarcinoma: prognostic implications.

OBJECTIVE: The expressions of minichromosome maintenance protein 2 (MCM2), Ki-67, and p53 were examined to analyze their pathobiological significance in human lung adenocarcinomas. METHODS: We performed Western blot analysis in six human lung adenocarcinoma cell lines and immunohistochemistry in 145 surgically removed adenocarcinomas to examine the MCM2 expression. Labeling indices (LIs; %) of MCM2, Ki-67, and p53 in the tumor cells were compared with clinicopathological profiles and overall survival rates. RESULTS: MCM2 protein was detected in all cell lines examined, with specific bands. MCM2 LIs were significantly correlated with sex, histological type, differentiation, pathological stage, and LIs of Ki-67 and p53 (p < 0.05). Significantly higher LIs of MCM2 and Ki-67 were noted in the 122 non-pure bronchioloalveolar carcinomas than in the 23 pure bronchioloalveolar carcinomas (p < 0.01), and the prognosis was poorer in the former than in the latter (p < 0.01). Sex, pathological stage, and high LIs of MCM2 and/or Ki-67 were independent prognostic factors (p < 0.05). CONCLUSION: High LIs of MCM2 and/or Ki-67 suggest a poor prognosis in patients with lung adenocarcinoma (non-pure bronchioloalveolar carcinoma).     

Adherence to, invasion by, and cytokine production in response to serotype VIII group B Streptococci

The adherence to and invasion of the human epithelial cell line A549 by group B streptococcus (GBS) serotype VIII strains were compared with those of serotype III strains by a conventional method and the dynamic in vitro attachment and invasion system. Twenty GBS strains, including nine vaginal isolates and one invasive isolate each of serotypes III and VIII, were used in the conventional attachment and invasion assay. Adherence to and invasion of A549 cells by serotype VIII GBS strains were significantly greater (P < 0.0001) than those by serotype III strains for both the invasive strain and vaginal isolates. Cytokine production by A549 cells following stimulation with GBS serotypes III and VIII or their purified capsular polysaccharides (CPS) was measured. Serotype III strains stimulated significantly greater tumor necrosis factor alpha (TNF-alpha) (P < 0.0001) and interleukin-10 (IL-10) (P < 0.05) production than did serotype VIII strains. IL-8 production in response to serotype VIII was significantly higher (P < 0.001) than that in response to serotype III. TNF-alpha, IL-8, and IL-10 production was greater in A549 cells infected with GBS than in the untreated control cells. TNF-alpha production was significantly greater (P < 0.005) after stimulation with purified GBS serotype III CPS than after stimulation with serotype VIII CPS, a result similar to that after stimulation with whole GBS. IL-12 production by A549 cells was observed only in response to infection with GBS serotype III, resulting in the possibility of a greater TH1 response in serotype III GBS. These results suggest differences in immune responses to infection with GBS serotypes III and VIII.     

Methamphetamine effects on rat circadian clock depend on actograph

Methamphetamine effects on the rest-activity rhythm were examined in 12 blinded rats using two different actographs, an Animex and a running-wheel. D-Methamphetamine was administered chronically by dissolving it in drinking water. During methamphetamine treatment, the rest-activity rhythm measured by an Animex showed a clear sign of relative coordination in addition to the general enhancement of activity level. Analyses of pre- and posttreatment activity rhythms revealed that neither the phase nor the period was affected by methamphetamine treatment. On the other hand, the circadian period was lengthened by methamphetamine treatment when locomotor activity was measured by a running-wheel. These results confirmed our previous findings that the chronic treatment of methamphetamine modified the expression of the circadian rhythms but did not affect the underlying oscillation when measured by an Animex, and further indicated that methamphetamine could affect the underlying oscillation when rats had free access to a running-wheel. It is concluded that the effects of methamphetamine on the circadian clock depend on actograph.     

Activity rhythms in the circadian domain appear in suprachiasmatic nuclei lesioned rats given methamphetamine

Female rats were lesioned in the suprachiasmatic nuclei (SCN) electrolytically and treated with methamphetamine. The SCN lesions abolished the circadian locomotor rhythm completely. When methamphetamine was administered in the drinking water, robust rhythmicities in locomotor activity appeared in the SCN lesioned rats, which did not entrain to the 24 hr light cycle. The period of the activity rhythm was dose-dependent; the lower the concentration of methamphetamine was, the shorter the period of the rhythm became. When rats were treated with 0.005% methamphetamine, the mean period was 26.4 hours. In addition, activity time () became shorter, rest time () longer and / ratio lower, when methamphetamine concentration was decreased. After methamphetamine withdrawal, the rhythmicity disappeared and locomotor activity became aperiodic again. When methamphetamine was administered continuously by means of an osmotic minipump, similar rhythmicities appeared in locomotor activity of the SCN lesioned rats. It is concluded that methamphetamine manifests an activity rhythm whose period is in the circadian range. The rhythmicity is independent of the SCN and is not entrained by the light-dark cycle.     

A novel auxiliary partial orthotopic liver transplantation model in rats

BACKGROUND: Although auxiliary partial orthotopic liver transplantation (APOLT) has become a well-accepted procedure recently, a practical experiment model in APOLT using small animals has yet to be developed. METHODS: Male Lewis rats were used for both donors and recipients. An auxiliary partial graft was obtained by ex vivo resection of the donor right and caudate lobes, and was transplanted orthotopically into the recipient after resection of the recipient medial and left hepatic lobes. Portal vein and hepatic duct reconstructions were by the cuff technique, and supra- and intrahepatic vena cava were sutured continuously. Operative outcomes, serum chemistry, liver tissue blood flow, angiographic and histopathological findings were then examined. Conventional orthotopic liver transplantation (OLT) procedures were also undertaken as a control. RESULTS: One-day, 1-week and 1-month survival rate of APOLT group was 100, 85 and 85%, respectively. AST in the APOLT group on the 1st postoperative day was significantly higher than in the OLT group. No significant differences were recognized in serum albumin and total bilirubin levels between the two groups. Although the portogram of an APOLT rat showed slight narrowing at the cuff anastomosis site, both the graft and the native liver were opacified similarly. The liver tissue blood flow on the 5th postoperative day in the native liver and the graft returned to as high as 95 and 74% of the values on laparotomy, respectively. Histological examinations of the auxiliary graft 1 month after transplantation showed mild ductular proliferation and mononuclear cell infiltration around the portal triads. CONCLUSION: This novel APOLT model in rats allows practical and reproducible results, and may be of value in the basic study of APOLT procedures.     

Bronchoplastic lobectomy with wide wedge resection for lung cancer with long-term steroid medication

A 57-year-old man with erythrodermia, who was given 5-10 mg/day of prednisolone for 2.5 years, was admitted to our hospital for squamous cell lung carcinoma of the right upper lobe. A bronchoscopy revealed a tumor nearly obstructing the right upper lobe bronchus. A bronchoplastic lobectomy was performed with wide wedge resection of the main bronchus and truncus intermedius. A postoperative bronchoscopy revealed good healing of the anastomosis and a 3-dimensional construction of the bronchus with chest computed tomography demonstrated no stenotic change and no kinking change in the anastomosis. One year and 6 months after surgery, no local recurrence was seen in the region of bronchoplasty. Bronchoplastic lobectomy with wide wedge resection is a useful procedure in cases with risk factors of anastomotic dehiscence, such as after induction therapy or during long-term administration of adrenal cortical steroids.