The antiulcerative effect of Thai Musa species in rats.

Bananas are reported to have an antipeptic ulcer effect, however, the beneficial action can be affected by many factors, including the variety. Our study was undertaken to investigate the antipeptic ulcer effect of the Palo and Horn varieties of banana, grown and consumed in the northeast of Thailand. Indomethacin and acetic acid-induced gastric lesions in rats were employed as models of peptic ulcer disease. The lengths of gastric lesions in the glandular part of the stomach were measured for the assessment of the protective effect of bananas. The healing effect was studied by histological examination of the ulcerated area. The lesions in rats treated with the extract of banana were significantly less dominant than those of the control. The average length of total lesions of rats treated with an extract of Palo or Horn bananas at a dose of 1.0 g/kg/d for 3 days prior to indomethacin administration were 4.47+/-1.2 and 1.87+/-0.44 mm, respectively, whereas those observed in the control rats were 14.56+/-2.43 mm. In the ulcer-healing model, only the Hom-banana-extract-treated group showed a beneficial effect which manifested as a milder degree of histological change than that of the indomethacin-induced-chronic-ulcer control group. However, in acetic acid-induced ulcers, the histological changes of every group were similar. The present findings indicate that bananas of different varieties have varying antipeptic ulcer effects. The extracts of Palo and Hom bananas have a prominent gastroprotective effect, whereas only the extract of Hom banana had an observed ulcer-healing effect.

Silver aids healing in the sterile skin wound: experimental studies in the laboratory rat.

Incisional wounds 15 mm long were induced surgically in the back skin of young adult Wistar rats. They were sutured and used as an experimental model in the therapeutic evaluation of daily applications of 0.5 mL of silver nitrate (SN) at 0.01, 0.1 or 1.0% w/v aqueous solution, or 0.5 g silver sulphadiazine (SSD) over a 10-day period. Control wounds received deionized water only. The silver preparations were not toxic but SN did stain the hair and superficial layers of the stratum corneum. The wounds remained microbiologically clean. Wounds exposed to SN (0.1 or 1.0%) or SSD healed more rapidly than controls. From about the fourth day of treatment, we noted a more rapid exteriorization of sutures, improved wound closure and an earlier loss of scabs and wound debris. Silver treatment appeared to reduce the inflammatory and granulation tissue phases of healing and enhance epidermal repair. Silver from SN was deposited as silver sulphide in extrafollicular hair shafts and superficial aspects of the skin and wound debris but not at deeper levels. Silver uptake was four-fold higher in damaged skin than in intact tissue. SSD was absorbed by intact and wounded skin but the silver did not precipitate as silver sulphide and its localization in the tissue is not known. Uptake of silver from SN or SSD was associated with changes in the concentrations of zinc and calcium in the skin. Zinc levels were depressed during the inflammatory and proliferative phases of healing and then increased. Zinc concentrations had normalized by 10 days when wound healing was achieved. Calcium levels remained higher than normal throughout the observation period. The mechanism of action of silver in advancing wound healing in the rat is unclear. Its ability to reduce the inflammatory and granulation phases of healing, and to invoke metallothionein production and influence metal ion binding are possibly important.

Experimental evaluation of local reactions due to Dacron used in Tenckhoff catheters for peritoneal dialysis.

Inbred male Wistar rats were implanted subcutaneously with samples of Dacron and Silastic tubing as used in Tenckhoff catheters for peritoneal dialysis, to evaluate their capacity to evoke toxic reactions. Implants of Dacron induced a modest to severe granulomatous reaction with giant cell formation persisting for at least 30 days. Thereafter, this reaction subsided, with Dacron fibers being surrounded by fibrous sheaths. Silastic tubing induced a mild local reaction that regressed by day 10. Predictably, adverse reactions, including erosions, abscesses, and prolonged inflammatory changes noted in clinical patients implanted with Tenckhoff catheters may be attributable to misplacements of the catheters, recurrent infections, or toxic materials from extraneous sources, but not the materials used.

The primary nephrotic syndrome in children and histopathologic study.

A retrospective study of 91 primary nephrotic syndrome with renal biopsies from January 1979 to February 1988 was done. The age of onset is divided into three groups, there are 23.0 per cent in age group 1- less than 5 years, 44.0 per cent in group 5-10, and 33.0 per cent in age group greater than 10-15 years. The ratio male to female is 2.1:1. The histopathologic findings are 16.5 per cent MCNS, 12.0 per cent FGN, 33.0 per cent MesPGN, 30.8 per cent MPGN and 7.7 per cent MGN. This study showed that 77.7 per cent of children with primary nephrotic syndrome have the age of onset older than 5 years. The most common histopathologic finding is MesPGN which is reported to be an interchangeable form with MCNS. The result of low incidence of MCNS may be related to the high percentage of MesPGN. The high incidence of MesPGN and MPGN may result from environmental factors such as chronic infection and malnutrition. (MCNS = minimal change nephrotic syndrome, FGN = focal glomerulonephritis, MPGN = membranoproliferative glomerulonephritis, MesPGN = mesangial proliferative glomerulonephritis, MGN = membranous glomerulonephropathy).