Effect of magnolol on in vitro mitochondrial lipid peroxidation and isolated cold-preserved warm-reperfused rat livers

BACKGROUND/AIM: A mechanism suggested to cause injury to preserved organs is the generation of oxygen free radicals. Lipid peroxidation is one of the biological damages caused by oxygen free radicals. It is our aim to investigate whether magnolol, a strong antioxidant, suppresses the generation of oxygen free radicals and improves the viability of cold-preserved warm-reperfused rat livers. MATERIALS AND METHODS: In vitro lipid peroxidation was induced in rat hepatic mitochondria with ADP and FeSO4. The inhibitory effect of magnolol on lipid peroxidation was measured with oxygen consumption and malondialdehyde (MDA) formation. Subsequently, we preserved and reperfused rat livers in preservation solutions that contained magnolol. The hepatic enzymes and liver MDA were measured to assess the protective effect of magnolol on isolated rat livers. RESULTS: In rat hepatic mitochondria, magnolol was 470 times more potent than alpha-tocopherol in inhibiting oxygen consumption and 340 times more potent than alpha-tocopherol in inhibiting MDA formation. Addition of magnolol to Ringer's lactate solution had a protective effect, in terms of MDA formation and leakage of hepatic enzymes, on warm-reperfused but not cold-stored liver tissue. Addition of magnolol to University of Wisconsin (UW) solution, a widely used preservation solution, did not modify the effect of this solution on isolated liver tissues. CONCLUSIONS: We conclude that magnolol is an effective antioxidant and suppresses lipid peroxidation in rat liver mitochondria and can be used as a rinsing solution in protecting transplanted organs from lipid peroxidation during reperfusion, especially for those organs not preserved with UW solution.     

An open study of sertraline in patients with major depression who failed to respond to moclobemide

OBJECTIVES: The aim of this study is to evaluate the efficacy and tolerability of sertraline in patients with major depression who have failed to respond to an adequate trial of moclobemide. METHOD: Sixty-three patients with major depression who had discontinued moclobemide within the last 6 weeks due to lack of efficacy were recruited from multiple psychiatric services in Victoria and Queensland. After a wash-out period, patients were treated with sertraline 50 mg once daily for 4 weeks. If there was an insufficient response, the dose was titrated upwards to a maximum of 200 mg/day, with 2 weeks at each dosage level. By the end of the study, patients had received a fixed dose of sertraline for 8 weeks. The main outcome measures were the 17-item Hamilton Rating Scale for Depression (HAMD) and Clinical Global Impression (CGI) scales. Secondary outcome measures included the Montgomery-Asberg Depression Rating Scale (MADRS) and Beck Depression Inventory (BDI). RESULTS: Of the 62 intention-to-treat patients enrolled, 48 (77%) responded to sertraline (i.e. experienced > or =50% reduction in HAMD total score from baseline and had a final HAMD score of < or =17). Fifty-four (87%) patients were at least 'minimally improved' on the CGI scale. There were also significant improvements in mean total MADRS and BDI scores. Sertraline was well tolerated. Adverse events were reported by 84% of patients, but only 5% withdrew due to adverse events. CONCLUSIONS: This study shows that patients with major depression who have failed to respond to moclobemide can generally be treated successfully with sertraline.     

No association between an intronic presenilin-1 gene polymorphism and schizophrenia in a Chinese population

We investigated the association between schizophrenic psychosis and an intronic polymorphism of the presenilin-1 (PS1) gene in a Chinese population. Schizophrenic and control groups had similar PS1 genotype distributions and allele frequencies, indicating that this polymorphism may not be involved in the development of schizophrenia.     

Autogenous venous nerve conduits. A review

Autogenous venous nerve conduit (AVNC) has evolved from an experimental idea to a clinical reality over the last two decades. The effectiveness of AVNC for reconstruction of a peripheral nerve with a nerve gap of less than 3 cm has been established and confirmed. An exciting application of this technique in the near future is to use the conduit as a vehicle for moderation and modulation of the cellular and molecular ambience for nerve regeneration.     

Balancing the equation: The significance of professional and lay perceptions in the promotion of cervical screening amongst minority ethnic women

Studies of minority ethnic women and cancer screening have, in the past, suffered from many theoretical and methodological weaknesses. In addition, no attempts have been made to study the complexity of the issue involved in the intercultural context, or the possible contribution of women's experiences to low uptake rates. In order to further our understanding of the issues, an alternative approach, participatory action research (PAR), was adopted to identify factors that might have contributed to the persistently low participation of minority ethnic women in the cervical screening programme, and address them collaboratively. This paper presents the key findings of the ‘problem identification' phase of the project. Using mainly the focus-group method, it explores both smear takers' and minority ethnic women's perceptions and experiences of cervical screening. Data suggest that there was a divergence in perceptions held by these groups regarding cervical screening, which contributed to negative experiences for both groups. There is also clear evidence of dysfunctional clinical communication arising from these differing perceptions. Opportunistic screening at post-natal examination adopted by many general practices appeared to have perpetuated the perceptions that the majority of minority ethnic women held about the purpose of the smear test. Compounded by language differences, the majority of women who had undergone smear testing understood neither the purpose of screening programme nor the procedure of the test. This has clear implications for promoting regular uptake, and more importantly for informed consent and choice.     

Design and synthesis of novel alpha(1)(a) adrenoceptor-selective antagonists. 1. Structure-activity relationship in dihydropyrimidinones

Dihydropyrimidinones such as compound 12 exhibited high binding affinity and subtype selectivity for the cloned human alpha(1a) receptor. Systematic modifications of 12 led to identification of highly potent and subtype-selective compounds such as (+)-30 and (+)-103, with high binding affinity (K(i) = 0.2 nM) for alpha(1a) receptor and greater than 1500-fold selectivity over alpha(1b) and alpha(1d) adrenoceptors. The compounds were found to be functional antagonists in human, rat, and dog prostate tissues. Compound (+)-103 exhibited excellent selectively to inhibit intraurethral pressure (IUP) as compared to lowering diastolic blood pressure (DBP) in mongrel dogs (K(b)(DBP)/K(b)(IUP) = 40) suggesting uroselectivity for alpha(1a)-selective compounds.     

Lorazepam for chronic catatonia: a randomized, double-blind, placebo-controlled cross-over study

Acute catatonic syndromes occurring in the context of various medical and neuropsychiatric conditions, including schizophrenia, have been shown to respond well to benzodiazepines (BZD). However, there have been no studies specifically designed to address the BZD treatment response of persistent catatonic states. Eighteen patients with clinically stable chronic schizophrenia, who also displayed enduring catatonic features, underwent a 12-week long, random assignment, double-blind, placebo-controlled cross-over trial with lorazepam (6 mg/day). A comprehensive assessment, including the subjects’ clinical and motor (catatonic as well as drug-induced movement disorders) condition, was performed at baseline and four weekly intervals thereafter. Pre-existing medication was kept constant throughout the study. Lorazepam had no effect on the subjects’catatonic signs and symptoms, suggesting that acute and chronic catatonic syndromes associated with schizophrenic illness might have a different neurobiological basis. Received: 25 May 1998/Final version: 22 September 1998     

PREVALENCE OF MICROALBUMINURIA IN NON-INSULIN-DEPENDENT DIABETES MELLITUS

The prevalence of microalbuminuria was assessed in 50 patients of non-insulin dependent diabetes mellitus. The mean age of patients was 52.1 ± 11.6 years and the duration of diabetes was 8.3 ± 6.8 years. Twenty (40%) patients had microalbuminuria. Microalbuminuria was more common in patients with a longer duration of diabetes (more than 5 years), a poor glycaemic control, and higher systolic blood pressure.KEY WORDS: Microalbuminuria, Diabetes mellitus, Diabetic nephropathy, Chronic renal failure     

Mechanism of activation of an N-ras oncogene of SW-1271 human lung carcinoma cells.

An N-ras-related transforming gene was detected in the human lung carcinoma cell line SW-1271 and molecularly cloned. The lesion responsible for its acquisition of transforming activity was localized to a single nucleotide transition from A to G in codon 61 of the predicted protein. This lesion in the second exon results in the substitution of arginine for glutamine at this position. These findings, together with previous studies, indicate that the activation of ras oncogenes in human tumors is most commonly due to point mutations at one of two major "hot spots" in the ras coding sequence.