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To solve the common issue of transverse thickness variation in finished strip steel during the sevenstand hot continuous rolling process, the deformation of rolls in the rolling process of beam Steel 700L and the genetic characteristics of plate thickness distribution were analysed by finite element simulation. Using actual process parameters from the production of beam Steel 700L, a dynamic rolling finite element model was established. The equivalent stress field between the working rolls and strip steel in each stand and the exit thickness distribution of beam Steel 700L were investigated. Results show that the equivalent stress indicates a gradual increase despite a decreasing reduction rate during rolling. Deviations in thickness between the centre and edges of the strip steel at the exit of each stand become apparent from the second stand onwards, demonstrating a hereditary phenomenon during the rolling process. A comparison of measured and simulated thickness reveals errors within 5 %, validating the accuracy of the simulation. The obtained findings provide a foundational understanding for addressing thickness defects in subsequent beam Steel 700L production. [ABSTRACT FROM AUTHOR]

Abstract: The study was designed to evaluate the effects of diethyldithiocarbamate (DDC), an superoxide dismutase (SOD) blocker on endothelial function in db/db mice. The db/db and wild-type (WT) mice were randomly divided into low intensity exercise, moderate intensity exercise and control (sedentary) groups. Mice were exercised daily, 5 days per week. After 6 weeks, ring segments of aortae were mounted in wire myograph and acetylcholine (ACh) concentration response curves were recorded in absence or presence of DDC and DDC plus SOD. Results showed that ACh concentration response curve was similar in WT and WT exercised groups. Incubation of aorta rings of WT mice with DDC suppressed the maximum ACh response (p <0.05). Subsequent incubation with SOD restored vasodilatory response in WT mice. The vasodilatation to ACh was significantly reduced in sedentary db/db mice compare to WT (p <0.05) and incubation with DDC did not further decrease this response, however, addition of SOD restored the vasodilatation to ACh to that observed in WT mice. Mild and moderate exercised db/db mice had ACh response similar to that in WT mice. Incubation with DDC incubation reduced ACh induced vasodilatation and addition of SOD restored this response. Our results support the conclusion that SOD mimetics can be used to improve superoxide-mediated endothelial dysfunction in diabetic db/db mice. [Copyright &y& Elsevier]

Paraquat (PQ) is a highly toxic herbicide that is used in most of the countries without restriction. The cytotoxic effect of PQ is mediated by radicals, which are the products of PQ reduction in cells. The anti-oxidative action of captopril, an angiotensin-converting enzyme inhibitor, appears to be through its ability to scavenge reactive oxygen species. In this study, the heptoprotective effect of captopril against PQ-induced hepatotoxicity was evaluated using primary cultured rat hepatocytes. Hepatocytes were isolated from male Wistar rats using a two-step collagenase perfusion, following incubation in the presence of captopril at 0.1, 0.2, 0.4 and 0.8 mM with or without PQ (5 mM). Hepatoprotective effects of captopril were studied indicating glutathione level intensity, thiobarbituric acid reactive substances (TBARs) formation, lactate dehydrogenase (LDH) leakage and cell viability every 70 min for 210 min. Captopril at 0.2 mM concentration maintained the LDH leakage, glutathione level and cell viability in the presence of 5 mM PQ. In spite of a significant elevation in TBARs formation in the PQ group, captopril did not show any significant protection. In conclusion, our data reveals that incubation of freshly isolated rat hepa-tocytes with captopril (0.2 mM) significantly protected the hepatocytes against the cytotoxicity of PQ (P < 0.05). [ABSTRACT FROM AUTHOR]

We have carried out an open clinical study in Somalia to evaluate the efficacy and safety of a simplified dosage schedule of metrifonate in the treatment of Schistosoma haematobium infection. The doses used were: We screened a total of 550 subjects in four villages for egg excretion in urine, and selected patients with more than 200 eggs per 10 ml of urine. In the initial phase of the study eight patients were assigned to each of the three dose schedules. In an extended study 38 additional patients were treated with regimen II which gave the best outcome in the initial study. Dosage Schedules I and III turned out to be toxic, and none of the patients was treated with all three doses. Adverse effects, such as abdominal colic, nausea, salivation, dizziness, and headache, were seen in almost all the patients in those two groups. Two patients from Group I reported that they fainted within 2 h after the second dose. None of the patients in Group II reported adverse effects. After 4-6 weeks follow-up, egg reduction was 96-100% for Groups I and II and the cure rate was around 60%. This study has shown that a shorter course of treatment with metrifonate might be equally effective and safer than the recommended dosage schedule with three doses of 7.5-10 mg · kg fortnightly. [ABSTRACT FROM AUTHOR]