Development and in vitro Evaluation of Enteric Coated Multiparticulate System for Resistant Tuberculosis

The multiparticulate formulation of sodium para aminosalicylate for oral administration was developed by extrusion spheronization technique. Microcrystalline cellulose was used as filler in concentration of 14.4% w/w. Pellets were coated with Eudragit L 30 D-55 using fluidized bed processor. Different weight gains of acrylic polymer were applied onto the pellets and evaluated for in vitro dissolution behavior in 0.1 N HCl for two hours and then media was changed to phosphate buffer pH 6.8. A 60% w/w coating level of Eudragit L30 D 55 has produced the most acceptable results against the gastric attack. 3% Seal coat of HPMC E5 was also applied in order to protect the drug from migration into the Eudragit coat and film coat was applied in order to prevent aggregation of pellets in the dissolution media. Morphological characteristics of developed pellets were also investigated by scanning electron microscopy and found to be smooth and spherical. Developed system was found to be suitable for the delivery of Sod PAS in to intestinal region.     

Effect of acute unilateral renal denervation on renal hemodynamics in spontaneously hypertensive rats

1 This study was undertaken to characterize the renal responses to acute unilateral renal denervation in anaesthetized spontaneously hypertensive rats (SHR) by examining the effect of acute unilateral renal denervation on the renal hemodynamic responses to a set of vasoactive agents and renal nerve stimulation. 2 Twenty-four male SHR rats underwent acute unilateral renal denervation and the denervation was confirmed by significant drop (P < 0.05) in renal vasoconstrictor response to renal nerve stimulation along with marked diuresis and natriuresis following denervation. After 7 days treatment with losartan, the overnight fasted rats were anaesthetized (sodium pentobarbitone, 60 mg kg(-1) i.p.) and renal vasoconstrictor experiments were performed. The changes in the renal vasoconstrictor responses were determined in terms of reductions in renal blood flow caused by renal nerve stimulation or intrarenal administration of noradrenaline, phenylephrine, methoxamine and angiotensin II. 3 The data showed that there was significantly (all P < 0.05) increased renal vascular responsiveness to the vasoactive agents in denervated rats compared to those with intact renal nerves. In losartan-treated denervated SHR rats, there were significant (all P < 0.05) reductions in the renal vasoconstrictor responses to neural stimuli and vasoactive agents as compared with that of untreated denervated SHR rats. 4 The data obtained in denervated rats suggested an enhanced sensitivity of the alpha(1)-adrenoceptors to adrenergic agonists and possible increase of AT(1) receptors functionality in the renal vasculature of these rats. These data also suggested a possible interaction between sympathetic nervous system and renin-angiotensin system in terms of a crosstalk relationship between renal AT(1) and alpha(1)-adrenoceptor subtypes.     

Applications of Azo-Based Probes for Imaging Retinal Hypoxia

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Spectrophotometric method for the determination of nifedipine with 4-(methylamino)phenol and potassium dichromate

A new simple, sensitive and reproducible spectrophotometric method for the determination of nifedipine in pure and dosage forms has been proposed. It is based on the reduction of nifedipine with Zn/NNH4Cl, followed by coupling with N-methyl-1,4-benzoquinoneimine--the oxidation product of 4-(methylamino)phenol, to give a chromophore which absorbed maximally at 525 nm. The experimental conditions were optimised and Beer's law was obeyed over the concentration range of 5-175 microg ml(-1). The molar absorptivity, detection limit, recovery and RSD were found to be 1.9 x 10(3) l mol(-1) cm(-1), 1.1 microg ml(-1), 99.7-100.5% and 0.3-0.8%, respectively. The proposed method was compared favourably with the official B.P. method.     

Bacteriological assessment of drinking water supply options in coastal areas of Bangladesh

This study was conducted to assess the bacteriological quality of alternative drinking water supply options in southwest coastal areas of Bangladesh. A total of 90 water samples were collected during both dry and wet seasons from household based rainwater harvesting systems (RWHSs), community based rain water harvesting systems (CRWHSs), pond-sand filters (PSFs) and ponds. The samples were evaluated for faecal coliform, Escherichia coli and Heterotrophic Plate Count, as well as Vibrio cholerae, Salmonella spp., Shigella spp. and Pseudomonas spp. Physico-chemical parameters (pH, electrical conductivity, and color) were also examined. In addition, sanitary inspections were conducted to identify faecal contamination sources. All options showed varying degrees of indicator bacterial contamination. The median E. coli concentrations measured for RWHSs, CRWHSs, PSFs, and ponds were 16, 7, 11, and 488 cfu/100 ml during the wet season, respectively. Vibrio cholerae O1/O139, Salmonella and Shigella spp. were not found in any samples. However, Vibrio cholerae Non-O1/Non-O139 and Pseudomonas spp. were isolated from 74.4% and 91.1% of the water samples collected during the wet season. A maximum pH of 10.4 was found in CRWHSs. Estimation of the disease burden for all options in disability adjusted life years (DALYs) showed an increased disease burden during the wet season. According to sanitary inspections, poor maintenance and unprotected ponds were responsible for rainwater and PSF water contamination, respectively. The findings of the present study suggest that alternative drinking water supply options available in southwest coastal Bangladesh pose a substantial risk to public health.     

Correlation between total phenolic and mineral contents with antioxidant activity of eight Malaysian bananas (Musa sp.)

Correlations between total phenolic and mineral contents with antioxidant activities of pulps and peels from eight banana (Musa sp.) cultivars were studied. The total phenolic contents were determined using Folin-Ciocalteu colorimetric method, and antioxidant activities were measured using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay and ferric reducing antioxidant potential (FRAP) assay. The highest total phenolic content (76.37 ± 1.79 mg GAE/g d.w.) was obtained from the freeze-dried extract of fresh pulps of Raja cultivar. The maximum activity of DPPH (19.39 ± 0.15 mg TE/g d.w.) was recorded for the chloroform extract of dried peels of Mas cultivar. Meanwhile, the highest activity of FRAP was shown by most of the chloroform extracts of dried pulps, dominated by Awak cultivar (22.57 ± 0.13 mg TE/g d.w.). With few exceptions, peel extracts exhibited higher total phenolic content and stronger antioxidant activities than that of the pulps. Very weak correlation between total phenolic content and FRAP activity was observed, yet it is higher (r² = 0.1614, p < 0.0001) than that of total phenolic content and DPPH activity (r² = 0.02339, p < 0.05). A moderate correlation between DPPH and FRAP activities was obtained (r² = 0.3533, p < 0.0001). For mineral analysis, potassium (K) is the major element found in both fresh pulps and peels followed by P, Mg and Na. Fresh peels of Raja consisted the highest amount of K (1387.5 mg/100 g f.w.). With exception of Mn, no correlation was found between mineral content and antioxidant activity. A moderate correlation between Mn content and DPPH activity was observed (r² = 0.2855, p < 0.0001).     

The Indian Ocean dipole and cholera incidence in Bangladesh: a time-series analysis

Background

It has been reported that the El Niño–Southern Oscillation (ENSO) influences the interannual variation of endemic cholera in Bangladesh. There is increased interest in the influence of the Indian Ocean dipole (IOD), a climate mode of coupled ocean–atmosphere variability, on regional ocean climate in the Bay of Bengal and on Indian monsoon rainfall.

Objectives

We explored the relationship between the IOD and the number of cholera patients in Bangladesh, controlling for the effects of ENSO.

Methods

Time-series regression was performed. Negative binomial models were used to estimate associations between the monthly number of hospital visits for cholera in Dhaka and Matlab (1993–2007) and the dipole mode index (DMI) controlling for ENSO index [NINO3, a measure of the average sea surface temperature (SST) in the Niño 3 region], seasonal, and interannual variations. Associations between cholera cases and SST and sea surface height (SSH) of the northern Bay of Bengal were also examined.

Results

A 0.1-unit increase in average DMI during the current month through 3 months before was associated with an increase in cholera incidence of 2.6% [(95% confidence interval (CI), 0.0–5.2; p = 0.05] in Dhaka and 6.9% (95% CI, 3.2–10.8; p < 0.01) in Matlab. Cholera incidence in Dhaka increased by 2.4% (95% CI, 0.0–5.0; p = 0.06) after a 0.1-unit decrease in DMI 4–7 months before. Hospital visits for cholera in both areas were positively associated with SST 0–3 months before, after adjusting for SSH (p < 0.01).

Conclusions

These findings suggest that both negative and positive dipole events are associated with an increased incidence of cholera in Bangladesh with varying time lags.     

Achieving the millennium development goal for under-five mortality in Bangladesh: current status and lessons for issues and challenges for further improvements

The study assessed the achievements in, critically reviewed the relevant issues of, and put forward recommendations for achieving the target of the Millennium Development Goal relating to mortality of children aged less than five years (under-five mortality) in Bangladesh within 2015. To materialize the study objectives, a thorough literature review was done. Mortality of under-five children and infants decreased respectively to 65 from 151 and to 52 from 94 per 1,000 livebirths during 1990-2006. The immunization coverage increased from 54% to 81.9% during the same period. The projection shows that Bangladesh will achieve targeted reduction in under-five mortality and infant mortality within the time limit, except immunization coverage. Neonatal mortality contributed to the majority of childhood deaths. Contribution of neonatal mortality to child mortality was the highest. There were remarkable differences in child mortality by sex, division, and residence. To progress further for achieving the target of MDG relating to child mortality, some issues, such as lower use of maternal healthcare services, hazardous environmental effects on childhood illness, high malnutrition among children, shorter duration of exclusive breastfeeding practices, various child injuries leading to death, low healthcare-use of children, probable future threat of financial shortage, and strategies lacking area-wise focus on child mortality, need to be considered. Without these, the achievement of MDG relating to child mortality may not be possible within 2015.     

Effects of xylitol as a sugar substitute on diabetes-related parameters in nondiabetic rats

Abstract The present study was examined the effects of xylitol feeding on diabetes-associated parameters in nondiabetic rats. Seven-week-old male Sprague-Dawley rats were randomly divided into three groups: control (five rats), sucrose (six rats), and xylitol (six rats). Animal had free access to a commercial rat pellet diet, and ad libitum water, 10% sucrose solution, and 10% xylitol solution were supplied to the control, sucrose, and xylitol groups, respectively. After 3 weeks of feeding of experimental diets, food intakes were significantly (P<.05) lower in the sucrose and xylitol groups compared with the control group. Drink intake was significantly higher in the sucrose group but significantly lower in the xylitol group compared with the control group. Body weight gain was significantly lower in the xylitol group compared with the sucrose group. Weekly nonfasting blood glucose was significantly increased, but fasting blood glucose was significantly decreased, in the sucrose group compared with the control and xylitol groups. Significantly better glucose tolerance was observed in the xylitol group compared with the control and sucrose groups. Serum insulin and fructosamine concentrations were not significantly influenced by the feeding of xylitol or sucrose. Relative liver weight and liver glycogen were significantly increased in the xylitol group compared with the sucrose group, whereas no difference was observed between the xylitol and control groups. Serum total cholesterol and low-density lipoprotein-cholesterol were significantly decreased in the sucrose and xylitol groups, and serum triglyceride of the xylitol group, but not the sucrose group, was significantly increased compared with the control group. Data of this study suggest that xylitol can be a better sweetener than sucrose to maintain diabetes-related parameters at a physiologically safer and stable condition.