The effect of exogenous nitric oxide on endothelial dysfunction in two-kidney, one-clip renovascular hypertensive rats

Previous studies have shown that hypertension causes endothelial dysfunction. To study the influence of exogenous nitric oxide(NO) on endothelial dysfunction produced by hypertension, we administered a non-depressor dose of nipradilol to two-kidney, one-clip renovascular hypertensive rats(2K1C). Sprague-Dawley rats underwent either sham surgery(G-1) or clipping of the left renal artery. From day seven, 2K1C were randomized into 3 groups, placebo treatment(G-2), nipradilol treatment(G-3,) and propranolol treatment(G-4). Urinary NO2- + NO3-(NOx) excretion (UNOx V) was measured 4 weeks after clipping, and then, acetylcholine(Ach), A23187, or sodium nitroprusside(SNP)-induced relaxation were measured in the aorta. Blood pressure was increased in G-2, G-3, and G-4 compared to G-1. UNOx V was lower in G-2, G-3, and G-4 compared to G-1, but UNOx V was higher in G-3 compared to G-2 and G-4. Although Ach or A23187-induced relaxation was significantly decreased in isolated artery from G-2, G-3, and G-4 compared with those from G-1. Ach- or A23187-induced relaxation was improved in G-3. SNP-induced relaxation did not differ among the 4 groups. These results suggest that exogenous NO from nipradilol reduces the endothelial dysfunction caused by hypertension without changing the blood pressure.     

Oral supplementation with gamma-linolenic acid extracted from Mucor circinelloides improves the deformability of red blood cells in hemodialysis patients

BACKGROUND: The development of abnormalities in red blood cell (RBC) deformability in patients undergoing hemodialysis remains a major problem, because it is related to peripheral microcirculation, oxygen supply, and various complications in such patients. gamma-Linolenic acid (GLA; 18:3n-6), one of the polyunsaturated fatty acids and a precursor of prostaglandin E(1), is reported to have a favorable effect on the deformability of circulating blood cells in diabetic patients. METHODS: In order to clarify the efficacy of GLA on RBC deformability in 7 patients undergoing maintenance hemodialysis, we examined in a pilot study the changes in the deformability of RBC and the changes in the phospholipid fatty acid composition in both plasma and RBC membrane before and after high-dose oral supplementation with GLA derived from Mucor circinelloides for 12 weeks. RESULTS: Before supplementation, the micropore passage time of RBC suspension, which is an indicator of RBC deformability, in these patients was markedly longer than that in healthy control subjects. After administering GLA, the prolonged passage time of the patients both rapidly and steadily decreased and nearly reached control levels. Light microscopic observations of RBCs using Giemsa stain revealed a decreased number of poikilocytes after supplementation. An analysis of the fatty acid composition before treatment and 8 weeks after starting the treatment showed the dihomo-gamma-linolenic acid (DGLA; 20:3n-6) level in the plasma to have increased (p < 0.05), while the arachidonic acid (AA; 20:4n-6) concentration in the RBC membrane decreased (p < 0.05). The level of DGLA in the RBC membrane, the level of GLA, and the ratio of GLA + DGLA/AA in plasma and RBC membrane did not change significantly; however, these all tended to increase. CONCLUSION: The results of this pilot study indicate that the oral supplementation of GLA extracted from M. circinelloides improves the poor RBC deformability in hemodialysis patients, partly by inducing changes in the composition of fatty acids in plasma and RBC membrane.     

Allelotype and replication error phenotype of small cell lung carcinoma

Allelotype and replication error (RER) phenotype analyses were performed to clarify the pathogenetic significance of inactivation of tumor suppressor genes and genomic instability in the genesis and progression of small cell lung carcinoma (SCLC). We examined 37 cases of SCLC for loss of heterozygosity (LOH) and microsatellite instability at 49 loci on all 39 nonacrocentric chromosomal arms. LOH was frequently (>70%) detected on chromosomes 3p (29/32, 90.6%), 5q (15/21, 71.4%), 13q (25/26, 96.2%), 17p (22/25, 88.0%), and 22q (24/33, 72.7%). Frequent LOH (>70%) on these loci was observed even among seven cases of stage I tumors. The incidence of LOH on all 39 nonacrocentric chromosomal arms was not significantly different between primary tumors and metastases. These results suggest that inactivation of multiple tumor suppressor genes accumulates relatively early during progression of SCLC and it may be responsible for clinically and biologically aggressive phenotype of SCLC. RER was observed in 6/37 (16.2%) of SCLC, however, RER at multiple loci was observed only in two cases. Therefore, it was indicated that genomic instability is uncommon, but might play a role in the genesis of a small subset of SCLC.      

The pineal gland is not essential for circadian expression of rat period homologue (rper2) mRNA in the suprachiasmatic nucleus and peripheral tissues

To investigate the functional involvement of the pineal gland in circadian expression of the rat period homolog gene (rPer2) in the suprachiasmatic nucleus (SCN) and peripheral tissues, we performed Northern blot analysis in tissues from pinealectomized rats. The ectomy did not have any significant effects on rPer2 mRNA expression patterns both in a daily light-dark condition and in a constant darkness. These results suggest that the rhythmic secretion of pineal melatonin is not essential for the circadian expression of clock genes in the SCN and other peripheral tissues of rats.     

A hybrid supported employment program for persons with schizophrenia in Japan

INTRODUCTION BY THE COLUMN EDITORS: Because the mental health system in Japan has emphasized hospital-based treatment (1), patients with schizophrenia often remain institutionalized for long periods, even after their symptoms have stabilized. In addition, the introduction of modern community-based methods of treatment and rehabilitation was delayed by an antipsychiatry movement in the 1970s and the ascendance of a reductionistic biological approach to services (2). Lack of adequate outpatient services and community residential care in Japan has been a serious obstacle to destigmatization of mental disorders and has contributed to the heavy burden and stress experienced by families of mentally ill persons (3). More than 80 percent of patients discharged from mental hospitals return to live with their families, who are ill prepared to provide the supportive services required for community tenure.Involvement in work activities can facilitate community reentry for people with serious and persistent mental illness because employment displaces symptoms, provides structure and meaning in daily life, offers socialization with peers, and permits workers to earn income for shelter and food. In this issue's Rehab Rounds column, the authors describe an innovative vocational rehabilitation program for patients with schizophrenia that was designed to overcome obstacles to discharge and community adjustment. The program at Yabuki Prefecture Psychiatric Hospital, in the northern prefecture of Fukushima, Japan, has been successful in training patients for competitive work while capitalizing on the importance of work in Japanese culture and its traditionally supportive employer-employee relationships. The program is termed "hybrid" because it combines elements of transitional employment with supported employment (4).     

Radical resection of hilar bile duct carcinoma and predictors of survival

BACKGROUND: Patients with carcinoma of the main hepatic duct have a poor prognosis. This study attempted to identify clinicopathological predictors of survival after resection. METHODS: A retrospective review was performed of 114 patients who presented with hepatic ductal carcinoma between 1976 and 1998. Of the 114 patients, 98 had a radical resection, three underwent palliative resection and 13 were not treated surgically. Forty-six patients with stage IVA disease had microscopic tumour residue after resection. Of these, 28 patients were treated with radiotherapy and the remaining 18 had resection alone. RESULTS: The overall operative morbidity and mortality rates were 14 and 4 per cent respectively. The overall 5-year survival rate after resection was 28 per cent. Nineteen patients survived for more than 5 years, including ten with stage IVA disease. The main prognostic factors were performance status; jaundice; tumour location; gross appearance; histological grade; T, N and M categories in tumour node metastasis (TNM) classification; TNM stage; and residual tumour. Adjuvant radiotherapy, tumour extension into the hepatic ducts, histological grade, N and residual tumour were independent predictive factors by multivariate Cox analysis. CONCLUSION: This study suggests that radical resection provides the best survival rate for patients with hilar bile duct carcinoma. For patients with stage IVA disease, following complete gross resection radiotherapy improved treatment outcome.     

Beta-hydroxybutyrate,a cerebral function improving agent,protects rat brain against ischemic damage caused by permanent and transient focal cerebral ischemia

In our previous study, beta-hydroxybutyrate (BHB) was found to prolong survival time and to inhibit cerebral edema by improving energy metabolism in the hypoxia, anoxia and global cerebral ischemia models. In this study, the cerebroprotective effect of BHB was examined in rats with permanent (p)-occlusion and transient (t)-occlusion of middle cerebral artery (MCA). BHB (30 mg x kg(-1) x h(-1) was continuously administered through the femoral vein. In rats with p-MCA occlusion, BHB significantly reduced infarct area at 24 h after the occlusion, but not at 72 h after the occlusion. In rats with 2-h t-MCA occlusion followed by 22-h reperfusion, BHB significantly reduced cerebral infarct area, edema formation, lipid peroxidation and neurological deficits. Moreover, in the t-MCA occlusion model, delayed administration of BHB started at 1 h after the initiation of the MCA occlusion also significantly reduced cerebral infarct area. Taking together the results obtained in our previous study into account, these results indicate that BHB decreased cerebral edema formation and infarct area by improving of the cerebral energy metabolism during ischemia and by inhibition of lipid peroxidation after reperfusion.     

Strain differences in cadmium-mediated suppression of lymphocyte proliferation in mice

Strain differences were investigated on the proliferative responses of splenic lymphocytes obtained from C3H/He, BALB/c, and DBA/2 mice that were treated with cadmium (Cd) for 5 days (0.5 or 1.0 mg Cd/kg/day, sc), and the results were compared with those of in vitro treatment of spleen cells with Cd. Following in vivo treatment, splenocytes from the C3H strain were significantly more susceptible to suppressive effects of Cd exposure on all indices for proliferative responses to mitogens (concanavalin A, phytohemagglutinin, and lipopolysaccharide) and allogeneic lymphocytes, while those from DBA and BALB strains were fairly resistant. Among the three strains, the highest Cd concentrations in plasma and spleen were obtained in the C3H strain with the lowest hepatic concentration of Cd. On the other hand, the Cd exposure hardly affected the splenic concentration of zinc in the C3H strain in contrast to its decrease in the others. When spleen cells obtained from normal mice were treated in vitro with Cd, the C3H strain was more resistant to the suppressive effect of Cd than the other strains. These results indicate that the mouse strain variations in Cd-mediated suppression of lymphocyte proliferation are not based on intrinsic lymphocyte sensitivities, but likely are due to differences in the metabolism of Cd, which is under genetic control.