Effect of aqueous extracts of black and green teas in arsenic-induced toxicity in rabbits.

Arsenic causes oxidative stress in the body. Its administration (3 mg/kg/day) for 14 days in rabbits resulted in a significant reduction of whole blood glutathione (GSH), and elevation of thiobarbituric acid reactive substances (TBARS) and the index of nitrite/nitrate (NOx) levels. These are the markers of oxidative stress. Both black tea (BT) and green tea (GT) (Camellia sinensis), when administered to the arsenic-treated rabbits for 14 days, caused a significant elevation of the depleted GSH level to 53.12% and 57.47%, respectively. On the contrary, in the placebo group the level was 26.59%. The BT and GT reduced the elevated TBARS level to 43.27% and 62.28%, respectively, whereas the corresponding level in the placebo groups was 21.24%. The NOx levels were also reduced to 63.62%, 67.67% and 58.94% in BT, GT and the placebo groups, respectively. When arsenic and black tea were given concurrently to another group the results were even more pronounced. The polyphenol components of black and green tea were 27.69% and 29.71% of the dry weight of the total extracts, respectively. These results indicated that arsenic-induced toxicities in rabbits were significantly reversed by the black and green tea polyphenols. The greater activity of green tea than that of black tea correlates with the slightly higher content of polyphenols in green tea.

Excessive use of avoidable therapeutic injections in the upazilla health complexes of Bangladesh.

Injection use problem in the hospitals of upazilla health complexes (UHCs) of Dhaka and Noakhali districts was studied through small group discussion with the health personnel of each the UHCs. The group discussion revealed that in the hospitals of UHCs of Dhaka, the antibiotic injections were used in 70% to 100% of the encounters in ARI/pneumonia. In dehydration, I.V. fluid and antimicrobial injections were used in 60% to 100% of the encounters. Similarly 60% to 70 % of the encounters received analgesic and antibiotic injections in injury. Injections were used in > or =30% of the encounters in pyrexia of unknown origin. The use of injections in the hospitals of the UHCs of Noakhali was comparatively less than that of Dhaka, but was still too high. In ARI/pneumonia antibiotic injections were used in 60% to 80% of the encounters. In dehydration, I.V. fluid and antimicrobial injections and in injury, analgesic and antibiotic injections were used in 60% to 80% of the encounters in each of the health conditions. In weakness, I.V. fluid and amino acid injections were used in 100% and 50% of the encounters respectively. In undiagnosed fever antibiotic injections were use in 60% of the encounters. The findings of the retrospective prescribing survey in those health complexes of the two districts corroborated the findings of the small group discussion. In the UHCs of Dhaka districts excessive injections were used in (i) ARI/pneumonia, (ii) dehydration and (iii) in injury. In ARI/pneumonia antibiotic injections were used in 100%, 94%, and 75% of the encounters in Dohar, Savar and Nawabgonj UHCs respectively. In dehydration, I.V. fluid was used in 100% and 89% of the encounters in Dhamrai and Keranigonj UHCs respectively. The I.V. fluid was also used in 76% of the encounters in injury. In the UHCs of Noakhali the injection use was somewhat less than that of Dhaka. Ceftriaxone injection was used in 87% and 77% of the encounters in ARI/pneumonia in Companygonj and Sonaimuri UHCs respectively. In the other three UHCs, analgesic injections were used in 80%, 67% and 67% of the encounters in Subarnochar, Chatkhil and Senbag respectively.

Microbial keratitis: aetiological diagnosis and clinical features in patients admitted to Hospital Universiti Sains Malaysia.

INTRODUCTION: Corneal ulceration remains one of the major causes of blindness in developing countries, including Malaysia. Our objective is to determine the epidemiological characteristics, clinical features, risk factors and the aetiology of microbial keratitis in patients admitted to Hospital Universiti Sains Malaysia (HUSM). METHODS: All patients with microbial keratitis admitted to our hospital over a 16-month period from January 2004 to April 2005 were included in the study. Sociodemographic data and information pertaining to risk factors were recorded. All patients underwent examination with slit lamp biomicroscopy and corneal scrapings were sent for microbiological diagnosis. RESULTS: 42 patients were included in the study; 26 were male and 16 were female, with mean age of 44.5 (+/- 20.9) years. History of previous corneal trauma was present in 26 (61.9 percent) patients. Central location ulcers were more predominant (69 percent) than peripheral ulcers. Cultures from corneal scrapings were positive in 29 cases (69 percent). Of those individuals with positive cultures, 23 (79.3 percent) had pure bacterial infection, four (13.8 percent) had pure fungal infection and two (6.9 percent) had mixed growth. The most common bacterial pathogen isolated was Pseudomonas aeruginosa (40.5 percent), followed by Streptococcus pneumoniae (7.5 percent). Fungal pathogens which were isolated include Fusarium spp. (4.7 percent) and Aspergillus spp. (2.4 percent). CONCLUSION: Central corneal ulceration is a problem among patients presenting with microbial keratitis in HUSM. It often occurs after corneal trauma. These findings have important public health implications for the treatment and prevention of visual morbidity due to an infective cause.

Immobilisation of whole bacterial cells for anaerobic biotransformations.

Anaerobically grown cells of Escherichia coli were immobilised within a range of entrapment matrices and packed into a column under standard conditions, and the ability of the immobilised cells to reduce nitrite (0.5 mM) was measured at a range of flow rates using sodium formate (20 mM) as the electron donor for nitrite reduction. A flow-rate/activity plot was constructed for each flow-through reactor and RA1/2 values (residence time corresponding to 50% nitrite removal) calculated for each reactor type. Cells immobilised in flat and hollow-fibre membranes were the most effective (RA1/2 = 0.35 h and 0.47 h respectively), with cells entrapped by dialysis membrane (1.53 h), alginate beads (1.93 h), Hypol foam (2.31 h) and polyacrylamide gel (50% nitrite not removed at maximum residence time tested: 4.9 h) performing progressively less effectively. Cells grown as a biofilm on a range of support materials were also tested in comparable packed-bed reactors. Cell loss from these supports was extensive and contributed to poor performance of the reactors despite high initial biomass loadings (RA1/2 values using raschig rings, coke and activated-carbon supports: 1.6 h, 2.3 h and 1.0 h respectively). Biofilms grown on Pharmacia microcarrier supports and used in packed and also fluidised beds were more stable and the performance of these reactors was superior to that of biofilm reactors using other supports, and comparable to that of the membrane reactors (RA1/2 values for Cytoline 2, Cytopore 2 and Cytodex 3: 0.76 h, 0.56 h, 0.68 h respectively).