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Potassium bromate (KBrO3) is widely used as a food additive and is a major water disinfection by-product. It induces multiple organ toxicity in humans and experimental animals and is a probable human carcinogen. The present study reports the protective effect of dietary antioxidant taurine on KBrO3-induced damage to the rat intestine. Animals were randomly divided into four groups: control, KBrO3 alone, taurine alone and taurine+ KBrO3. Administration of KBrO3 alone led to decrease in the activities of intestinal brush border membrane enzymes while those of antioxidant defence and carbohydrate metabolism were also severely altered. There was increase in DNA damage and DNA-protein cross-linking. Treatment with taurine, prior to administration of KBrO3, resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. Histological studies supported these biochemical results showing extensive intestinal damage in KBrO3-treated animals and greatly reduced tissue injury in the taurine+ KBrO3 group. These results show that taurine ameliorates bromate induced tissue toxicity and oxidative damage by improving the antioxidant defence, tissue integrity and energy metabolism. Taurine can, therefore, be potentially used as a therapeutic/protective agent against toxicity of KBrO3 and related compounds.

In the present study, we have studied the effect of KBrO3 on human erythrocytes under in vitro conditions. Erythrocytes were isolated from the blood of healthy nonsmoking volunteers and incubated with different concentrations of KBrO3 at 37°C for 60 min. This resulted in marked hemolysis in a KBrO3 -concentration dependent manner. Lysates were prepared from KBrO3 -treated and control erythrocytes and assayed for various parameters. KBrO3 treatment caused significant increase in protein oxidation, lipid peroxidation, hydrogen peroxide levels, and decrease in total sulfhydryl content, which indicates induction of oxidative stress in human erythrocytes. Methemoglobin levels and methemoglobin reductase activity were significantly increased while the total antioxidant power of lysates was greatly reduced upon KBrO3 treatment. Intracellular production of reactive oxygen species increased in a dose dependent manner. Exposure of erythrocytes to KBrO3 also caused decrease in the activities of catalase, glutathione peroxidase, thioredoxin reductase, glucose 6-phosphate dehydrogenase and glutathione reductase whereas the activities of Cu-Zn superoxide dismutase and glutathione-S-transferase were increased. These results show that KBrO3 induces oxidative stress in human erythrocytes through the generation of reactive oxygen species and alters the cellular antioxidant defense system.

Wounds are a commonly encountered and complex entity in healthcare, and often require multidisciplinary involvement for their management. Wound care and healing are affected by a range of factors of which nutrition, a modifiable factor, plays an integral part. Familiarity with the phases of wound healing and the differing nutritional requirements at each stage is fundamental to managing wounds. Additionally, awareness of the signs of malnutrition, screening tools and educational resources for managing malnutrition in primary care settings are all vital to minimising malnutrition and its adverse effects on wound healing. This article reviews the phases of wound healing and the associated nutritional requirements required for optimal healing, the clinical signs of malnutrition and screening resources for identifying at-risk groups, as well as reviewing current guidelines for managing malnutrition in the inpatient and outpatient setting.

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Potassium bromate (KBrO3 ) is widely used as a food-additive and is a major water disinfection by-product. KBrO3 causes severe toxicity in humans and experimental animals. Bromate is considered a probable human carcinogen and a complete carcinogen in animals. We have investigated the potential role of taurine in protecting against KBrO3 -induced oxidative stress in rat blood. Animals were given taurine for 5 days prior to KBrO3 and then sacrificed. Blood was collected and used to prepare hemolysates and plasma, which were then used for the analysis of several biochemical parameters. Administration of single oral dose of KBrO3 alone induced hepato- and nephro-toxicity as evident by elevated marker levels in plasma. Lipid peroxidation and protein oxidation were increased both in plasma and erythrocytes, suggesting the induction of oxidative stress. KBrO3 increased methemoglobin, nitric oxide, and hydrogen peroxide levels. It also altered the activities of the major antioxidant enzymes and lowered the antioxidant power of blood. Administration of taurine, prior to treatment with KBrO3 , resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. These results show that taurine is effective in mitigating the oxidative insult induced in rat blood by KBrO3 .

Potassium bromate (KBrO3) is widely used as a food additive and is a major water disinfection by-product. Several studies have shown that it causes nephrotoxicity in humans and experimental animals. We have investigated the potential role of the sulfonic amino acid taurine in protecting the kidney from KBrO3-induced damage in rats. Animals were randomly divided into four groups: control, KBrO3 alone, taurine alone and taurine + KBrO3. Administration of single oral dose of KBrO3 alone caused nephrotoxicity as evident by elevated serum creatinine and urea levels. Renal lipid peroxidation and protein carbonyls were increased while total sulfhydryl groups and reduced glutathione levels were decreased suggesting the induction of oxidative stress. The enzymes of renal brush border membrane were inhibited and those of carbohydrate metabolism were altered. There was an increase in DNA damage and DNA-protein cross-linking. Treatment with taurine, prior to administration of KBrO3, resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. Histological studies supported these biochemical results showing extensive renal damage in KBrO3-treated animals and greatly reduced tissue injury in the taurine + KBrO3 group. These results show that taurine is an effective chemoprotectant against bromate-induced renal damage and this amino acid could prove to be useful in attenuating the toxicity of this compound.

Sodium chlorate (NaClO) is a widely used non-selective herbicide. It is also generated as a byproduct during disinfection of drinking water by chlorine dioxide. In the present work, the effects of NaClO on human erythrocytes were studied under in vitro conditions. Incubation of erythrocytes with different concentrations of NaClO at 37 °C for 90 min resulted in significant hemolysis. Cell lysates were prepared from NaClO-treated and untreated (control) erythrocytes and assayed for various biochemical parameters. Methemoglobin levels were significantly increased and methemoglobin reductase activity was reduced upon NaClO treatment. There was a significant increase in protein oxidation and lipid peroxidation with a decrease in reduced glutathione and total sulfhydryl content. This suggests the induction of oxidative stress in erythrocytes upon exposure to NaClO. The occurrence of oxidative stress was confirmed by significantly increased generation of reactive oxygen species and lowered antioxidant response of the cells. NaClO treatment also increased nitric oxide levels showing induction of nitrosative stress. The activities of major antioxidant and membrane-bound and metabolic enzymes were significantly altered upon incubation of erythrocytes with NaClO. The erythrocytes became more osmotically fragile while electron microscopic images showed gross morphological alterations in NaClO-treated cells. These results show that NaClO induces oxidative stress in human erythrocytes, which results in extensive membrane damage and lowers the antioxidant response.