Decolourization and Detoxification of Azo Dye, Malachite Green by Pseudomonas monteilii Strain RZT1, a Bacterium Isolated from Textile Wastewater

Discharge of textile industrial effluent without proper treatment has become a severe hazard for the animal health and environment worldwide. Therefore, this study was designed to isolate azo dye-degrading bacteria from textile wastewater and evaluate their ability to biodegrade reactive dyes into non-toxic products. The potent bacterial strain which was isolated from textile wastewater was identified as Pseudomonas monteilii strain RZT1 on the basis of 16S rDNA sequence. The isolated bacterial strain exhibited good decolorization ability with yeast extract supplementation as cosubstrate in static conditions for Malachite Green dye. The optimal condition for the decolorization of Malachite Green dye by P. monteilii strain RZT1 were at pH 7.0 and 28癈. Decolorization rates of Malachite Green dye by P. monteilii strain RZT1 were varied with initial dye concentration as follow: 84.8%, 75.4%, 63.4% and 45.5% decolorization for 100ppm, 200ppm, 300ppm and 400ppm initial dye concentration respectively. We investigated the effects of dyes used in the textile industry on the seed germination of Five crops - Rice (Oryza sativa), Wheat (Triticum aestivum L.), Khesari (Lathyrus sativus), Mustard (Brassica nigra) and Bitter Melon (Momordica charantia). It was found that textile dye Malachite Green had negative effect on seed germination and seedling growth in test cultures. The harmful effects of dye on seed germination and early seedling growth parameters were augmented with increase of dye concentration. Interestingly, treatment of the Malachite Green dye with isolated bacteria reduced the adverse effects of that dye on seed germination and seedling growth. Thus, it indicated the potentiality of P. monteilii strain RZT1 for bioremediation of textile effluents into a non-toxic form for plants.

Reduction of Toxic Effects of Textile Dye, Basic Red-18 on Tilapia Fish by Bioremediation with a Novel Bacterium, Mangrovibacter yixingensis Strain AKS2 Isolated from Textile Wastewater

Due to rapid industrialization and market demand of vibrant textile products, the natural textile dyes have been replaced by the synthetic textile dyes. These synthetic dyes are released in environment with textile wastewater resulting in a major environmental pollution, especially in aquatic ecosystem. Hence, aquatic organisms like fish are highly vulnerable to the pollution caused by dyes of textile wastewater. This study was designed to evaluate the deleterious effects of Basic Red-18 (BR-18) dye on behavior, survivability, haematology and histology of Tilapia fish (Tilapia mossambica) and to minimize these deleterious effects of BR-18 dye by bioremediation with the novel bacteria isolated from textile wastewater. The isolated novel bacteria was identified as Mangrovibacter yixingensis strain AKS2 by 16s rRNA sequencing (Accession no. OM189530). The 30% and 70% mortality rates were observed in fish exposed to commercial BR-18 dye at concentrations of 100 and 200 ppm respectively. Interestingly, the mortality rate of fish was decreased significantly to 10% and 20% when fish were exposed to 100 and 200 ppm BR-18 dye respectively after bioremediation with M. yixingensis strain AKS2. Fish exposed to tap water and bioremediated BR-18 dye solution exhibited typical behavioral responses, whereas fish exposed to commercial BR-18 dye solution exhibited anomalous behavior. Fish subjected to commercial BR-18 dye solution displayed decreased RBC, Hb, but increased WBC levels, demonstrating the dye's haemotoxicity. Contrary, no remarkable haematological toxic effect was found when fish were exposed to bioremediated BR-18 dye indicating the non-toxic character of the bioremediated dye metabolites. Similarly, extensive histological abnormalities in the gill, liver, intestinal, stomach, and heart tissues were seen when fish was cultured in commercial BR-18 dye, but the abnormalities were less significant when fish were raised in bioremediated BR-18 dye. Altogether, it can be concluded that BR-18 dye are toxic to fish, but this toxicity can be minimized by bioremediation with M. yixingensis strain AKS2.

Anesthesia for emergency cesarean section.

Caesarean Section is one of the most common of all surgical procedures. Common indications for caesarean section may include foetal distress, Cephalopelvic disproportion and failure of labour to progress. Both regional and general anesthesia may be employed for caesarean section. Each is relatively safe and they have their own advantages and disadvantages. Actual decision to adopt one technique over another depends on maternal and foetal status and skill and ability of the anesthesiologist to tackle the situation with the aim of patient and baby safely. Among these, many of the cases come to the hospital as emergency basis. The Anesthesiologists have to face the challenge in providing anesthesia for emergency caesarean section, being the last member in the perinatal team. The challenge faces the risks in involvement of maternal changes in pregnancy, presence of foetal distress and various anesthetic complications arising in perioperative period. Still now anesthetic mishaps are considered as the sixth most frequent cause of maternal mortality. The use of regional Anesthesia reduced the number of deaths at about 80% but deaths involving general anesthesia has not decreased and the incidence is 17 times more than the regional anesthesia. Most of the deaths or complications are related to the airway management (also failed intubation). Better skill and knowledge in physiology, pharmacology and use of modern Anesthetic technique is essential to face the problems.

Management of dengue by the WHO guided national guidelines.

A total of 90 adult patients of Dengue admitted in Sir Salimullah Medical College and Mitford Hospital, Dhaka during the period from July 2002 to December 2002 were studied to see the presentation, spectrum of disease and outcome of management. Majority (52%) of cases was in the age group 21-30 years. Out of 90 patients 74 patients (82.22%) were male and 16 (17.78%) were female. Maximum number of cases (43%) was found in the month of August. Most of the cases (77%) were from Dhaka City. Classical type of Dengue fever was the commonest (80%) variety. Thrombocytopenia was found in 80% cases. Platelet count came down below 10000/cumm only in 1.1% of the patients. The patients were diagnosed mainly by clinical criteria. Serological tests were done only in selected cases. Majority (80%) of the patients was managed by sponging, paracetamol and Oral Rehydration Salt (ORS). Blood transfusion was required in 18% cases and platelet concentrate was given only in 1.1% cases. There was no mortality in this study.

Breast-feeding counselling and its effect on the prevalence of exclusive breast-feeding.

This prospective intervention study was undertaken to assess the impact of repeated breast-feeding counselling on the rate of exclusive breast-feeding up to five months. The study was carried out in two breast-feeding counselling sub-centres, established at the community level in the vicinity of two maternity facilities and one main centre established in an urban children hospital. Eighty-four pregnant mothers who attended the maternity facilities for delivery of babies were randomly selected and repeatedly counselled regarding breast-feeding--once just before delivery and subsequently at the completion of 1, 2, 3, 4, 5, 6, 9, and 12 month(s) of age of the child. These child-mother pairs comprised the intervention group. Another group of 90 child-mother pairs was selected from the maternity facilities. Mothers in this group (comparison group) received a single session of breast-feeding counselling just before delivery of babies. Fifty-nine and 55 child-mother pairs in the intervention and the comparison groups respectively completed the one-year follow-up. In the intervention group, 54.2% and in the comparison group 36.4% of the babies were exclusively breastfed up to five months of age. Forty-two (88%) children in the intervention group and 29 (53%) in the comparison group were given complementary foods at the optimum time, e.g. after completion of five months, and 81% of the children in the intervention group and 100% of the children in the comparison group were given complementary foods in the first year of life. It was observed that repeated organized breast-feeding counselling significantly improved the prevalence of exclusive breast-feeding to 54% which is much above the existing national prevalence (12.7%) in Bangladesh.

Oxygen free radicals in idiopathic facial pain.

Chronic idiopathic oro-facial pain has become a common complaint, resulting increasingly in referral to the pain clinics world-wide, about 90% of the psychologically stress-related patients of the psychiatric clinic of Eastman Dental Hospital, London have been found to have associated idiopathic oro-facial pain. Psychological stress may produce a situation where oxidative stress might enhance the production of free radicals, especially OH radicals, in human biological fluids. Furthermore, it has been suggested that. OH radicals are responsible for the production of many systemic and local tissue injury diseases which may initially manifest as pain syndrome. It has been suggested that the oxygen free radical production of sailcloth, 2,3-dihydroxybenzoic acid (DHB) is a biological marker for the detection and quantification of OH radicals. Analyses of plasma samples collected from patients with chronic idiopathic orofacial pain and an equal number of age and sex matched control subjects revealed that the patient group had significantly increased evidence for circulating levels of 2,3-DHB after aspirin ingestion than control subjects. There was no significant difference in 2,5-DHB levels between the two groups. The urine samples from the same individuals showed evidence of measurable amounts of 2,3 and 2,5-DHB in both pre- and post-aspirin samples. These results suggest that OFRs may be involved in the aetiology of pain in patients that present with facial pain.