Highly efficient recyclable bismuth nanocatalysts fabricated using a facile one-step aqueous method for faster reduction of azo dye contaminants.

Easily accessible robust synthesis of metallic nanoparticles (NPs) and their colloidal stabilization via successive surface functionalization with desired molecules are crucial for catalytic applications. In this research, tannic acid (TA)-functionalized bismuth (Bi)-based novel NPs were prepared via a simple in situ aqueous reduction of Bi3+ ions for the catalytic reduction of azo groups. The synthesis, morphology, and structure of Bi/TANPs were confirmed through spectroscopic, electron microscopic and X-ray diffraction analyses. The Bi/TANPs comprise Bi, carbon, oxygen and sodium as building components and possess a high negative surface charge of -58 mV, colloidal dispersity, thermal stability and crystalline structure. The Bi/TANPs are almost spherical shaped with an average diameter of 33 nm. The surface of the catalyst is mesoporous with a high specific surface area of 267 m2 g-1. The designed Bi/TANPs exhibit pH-specific affinity for azo dye molecules and reduced azo moieties in the presence of aqueous NaBH4 without requiring any hydrogen gas supply. The catalytic reduction efficiencies of Bi/TANPs against methylene blue and Congo red are almost 100%. These reduction reactions are very fast owing to the presence of TA moieties on the catalyst surface, which facilitate direct electron transfer to azo groups, and follow a pseudo-first-order kinetic model. The catalyst is mechanically recyclable, and shows a minimal loss (<3%) of its initial efficiency until the fifth cycle. This study not only developed an efficient catalyst for the remediation of azo dye-contaminated water, but also offers novel insights into the synergistic effects of TA and glycerin on the reduction mechanism of aqueous Bi3+ ions and the concomitant colloidal stabilization of Bi NPs.

The Versatile and Strategic O-Carbamate Directed Metalation Group in the Synthesis of Aromatic Molecules: An Update.

The aryl O-carbamate (ArOAm) group is among the strongest of the directed metalation groups (DMGs) in directed ortho metalation (DoM) chemistry, especially in the form Ar-OCONEt2. Since the last comprehensive review of metalation chemistry involving ArOAms (published more than 30 years ago), the field has expanded significantly. For example, it now encompasses new substrates, solvent systems, and metalating agents, while conditions have been developed enabling metalation of ArOAm to be conducted in a green and sustainable manner. The ArOAm group has also proven to be effective in the anionic ortho-Fries (AoF) rearrangement, Directed remote metalation (DreM), iterative DoM sequences, and DoM-halogen dance (HalD) synthetic strategies and has been transformed into a diverse range of functionalities and coupled with various groups through a range of cross-coupling (CC) strategies. Of ultimate value, the ArOAm group has demonstrated utility in the synthesis of a diverse range of bioactive and polycyclic aromatic compounds for various applications.

Serum Uric Acid and Serum Lipid Levels in Patients with Acute Ischemic Stroke Admitted in Mymensingh Medical College Hospital.

Stroke is the second-leading cause of death and also a leading cause of combined death and disability. In Bangladesh, stroke prevalence is 11.39 per 1000 population, but highest prevalence of stroke is 14.71 per 1000 population in the Mymensingh division. Hyperuricemia has been reported as an independent risk factor for stroke in different studies and a significant association between serum uric acid and dyslipidemia has also been stated. On the contrary, some studies suggest that uric acid has a neuroprotective role. This cross-sectional study was completed in the Medicine Department of Mymensingh Medical College Hospital, Mymensingh, Bangladesh from March 2021 to January 2023. In this cross-sectional study, 352 adult acute ischemic stroke patients were included from the Medicine Department of Mymensingh Medical College Hospital. Serum uric acid and fasting serum lipid levels were measured within 48 hours of admission. The mean age ±SD of the respondents was 61.9±12.8 years. Hyperuricemia was found among 18.2% of respondents, whose mean ±SD serum uric acid was 5.7±1.9 mg/dl. Dyslipidemia was present in 88.4% of patients. The mean ±SD of the National Institutes of Health Stroke Scale (NIHSS) score was 12.0±5.9. Most of the patients (65.6%) were suffering from moderate stroke, followed by moderate to severe stroke (15.1%), severe stroke (10.8%) and minor stroke (8.5%). After multiple linear regressions, the independent variables age, gender, serum uric acid and total cholesterol were found to be significant predictors of the NIHSS score of the respondents. In conclusion, the majority of acute ischemic stroke patients have an association with dyslipidemia, but only around one-fifth of patients have hyperuricemia. There is a significant association of high serum uric acid and high serum total cholesterol with stroke severity (NIHSS score). But low-density lipoprotein cholesterol, high-density lipoprotein cholesterol and, triglycerides have no association with stroke severity.

Fertilizer use gaps of women-headed households under diverse rice-based cropping patterns: Survey-based evidence from the Eastern Gangetic Plain, South Asia.

Women-headed households (WHHs) have limited access to agricultural inputs and extension services relative to male-headed households (MHHs) which may lead to yield gaps, poorer livelihoods and greater food insecurity. Since lower fertilizer use by WHHs will restrict crop yield, we examined how limited access to fertilizer inputs and extension services was reflected in nutrient use gaps relative to Government recommendations. A total of 80 WHHs were randomly selected for interview from four Agro-ecological Zones (AEZs) covering five representative districts of Bangladesh to assess, for the first time, nutrient use gaps of WHHs under five rice-based cropping patterns. Data collected from 576 MHHs (reported elsewhere) was also utilized to examine nutrient use gaps, crop yields and farm income between MHHs and WHHs. The nutrient use rates were compared with the government Fertilizer Recommendation Guides (FRG): FRG-2012 and FRG-2018. The WHHs underuse N, P, K, S and Zn under fully rice-based cropping patterns, while MHHs overuse those nutrients, but WHH tend to overuse N, P, and K for patterns with potato and watermelon crops. WHHs seem to prioritize high-value crops for fertilizer use, but even yield was 14%, 11%, 17% and 15% lower for irrigated rice, maize, potato and watermelon, respectively compared to smallholder MHHs under diverse rice-based cropping patterns. Overall, WHHs had 10% and 14% lower farm incomes than MHHs under fully rice-based and high-value cropping patterns, respectively. Financial losses for both WHHs and the government due to overuse of NPK on high-value potato crops were estimated at around 63 and 115 USD ha-1, respectively. However, the socio-demographic information suggested that effective extension services targeted to WHH, easing of social restrictions on their mobility, access of WHHs to fertilizers at Govt. fixed price and improved financial capability through better credit access could bring WHHs towards balanced fertilizer use practices in the EGP.

Unbalanced fertilizer use in the Eastern Gangetic Plain: The influence of Government recommendations, fertilizer type, farm size and cropping patterns.

Intensive cropping systems with diverse cropping patterns present a challenge for nutrient management on smallholder farms. Government-endorsed recommendations for crop fertilizer use are designed to assist farmers achieve profitable and balanced nutrient inputs, but it is unclear how closely farmers follow these recommendations. We identified farmers' current nutrient use gaps (overuse or underuse) relative to the Government-endorsed recommended nutrient doses in two cropping patterns in three representative Agro-ecological Zones of Bangladesh. A total of 330 farms were surveyed in 2019 from three farm size categories (referred to as large-, medium and small-scale) and their gaps in nutrient use were assessed relative to Government-endorsed Fertilizer Recommendation Guides (FRG) published in 2012 and in 2018: FRG-2012 and FRG-2018. The large- and medium-scale farms used 11-16%, 80-90% and 21-30%, respectively, over-doses of NPK in the cropping season under fully rice-based cropping pattern relative to FRG-2012 recommendations, while the over-dose levels were much lower for small-scale farms. Small-scale farms used much less than recommended S, Mg, Zn, B and organic manure (OM) rates relative to FRG-2012. The FRG-2018, which increased N and K recommendations but decreased the P recommendation for rice crops relative to FRG-2012, shows that all farms can decrease the dose of P (by 50%) while small-scale farms need to increase the dose of N (7%), K (16%), S (20%) and to apply Zn in the fully rice-based cropping pattern. On the other hand, the farms could greatly reduce NPK (19%, 86% and 44%, respectively) use while increasing S (14%), Mg, Zn, B and OM use relative to FRG-2018 in the pattern with the high-value potato crop. To increase crop profitability, enhance food security and save Government treasury in the Eastern Gangetic Plain enabling approaches are needed to effectively communicate the benefits of balanced nutrient use practices to farmers.

Farmers' fertilizer use gaps relative to government recommendations in the saline coastal zone of the Ganges Delta.

Overuse or underuse of nutrients relative to recommendations is a likely cause of crop yield gaps and an impediment to the achievement of food security. Government-endorsed recommendations are developed to deliver the best evidence-based advice on balanced fertilizer; however, deviations of farmers' nutrient use from the recommendations are rarely examined. This study chose the salt-affected coastal zone of the Ganges Delta, where low crop productivity and cropping intensity by smallholders limit their income, to determine current nutrient use gaps for the first time of three cropping patterns in two representative districts of Bangladesh. A total of 246 farms were surveyed from three farm sizes. Farmers' nutrient use gaps were compared with Fertilizer Recommendation Guides published in 2012 (FRG-2012) and 2018 (FRG-2018). Relative to FRG-2012 recommendations, farmers used 12%, 70%, and 11% overdoses of N, P, and K, respectively, under two fully rice-based cropping patterns, but the level of overdoses increased with farm size. Rates of K (14%), S (28%), and Zn use were below the FRG-2012 recommendations, especially for the smallest category of farms. However, the FRG-2018, increased recommended N (5%), K (62%), S (12%), and Zn rates but reduced P (25%) rates for fully rice-based cropping patterns. In contrast with rice, regardless of farm size, farmers applied overdose nutrients to watermelon but compensated with underdoses in the subsequent monsoon rice implying that farmers prioritized fertilizer expenditure on the most profitable crop. For the cropping pattern with watermelon, farmers could reduce the use of N (69%) and P (46%) and increase the use of K (48%), S (5%), and B. Reducing NPK use gaps can save treasury for both the farmers and the governments by 39.1 and 73.8 USD ha-1, respectively, under fully rice-based cropping patterns. Finally, our findings suggest there is scope to promote crop yields and sustainable intensification through balanced fertilizer use in a vulnerable saline region. Supplementary Information: The online version contains supplementary material available at 10.1007/s13593-022-00797-1.

Theoretical background, first stage development and adaptation of a novel Integrative Adapt Therapy (IAT) for refugees.

AIMS: Refugees are confronted with the task of adapting to the long-term erosion of psychosocial systems and institutions that in stable societies support psychological well-being and mental health. We provide an overview of the theoretical principles and practical steps taken to develop a novel psychotherapeutic approach, Integrative Adapt Therapy (IAT), which aims to assist refugees to adapt to these changes. This paper offers the background informing ongoing trials of IAT amongst refugees from Myanmar. METHODS: A systematic process was followed in formulating the therapy and devising a treatment manual consistent with the principles of the Adaptation and Development After Persecution and Trauma (ADAPT) model. The process of development and refinement was based on qualitative research amongst 70 refugees (ten from West Papua and 60 Rohingya from Myanmar). The therapeutic process was then piloted by trained interventionists amongst a purposively selected sample of 20 Rohingya refugees in Malaysia. RESULTS: The final formulation of IAT represented an integration of the principles of the ADAPT model and evidence-based techniques of modern therapies in the field, including a transdiagnostic approach and the selective use of cognitive behavioural treatment elements such as problem-solving and emotional regulation techniques. The steps outlined in refining the manual are outlined in relation to work amongst West Papuan refugees, and the process of cultural and contextual modifications described during early piloting with Rohingya refugees in Malaysia. CONCLUSIONS: IAT integrates universal principles of the ADAPT model with the particularities of the culture, history of conflict and living context of each refugee community; this synthesis of knowledge forms the basis for participants gaining insights into their personal patterns of psychosocial adaptation to the refugee experience. Participants then apply evidence-based techniques to improve their capacity to adapt to the serial psychosocial changes they have encountered in their lives as refugees. The overarching goal of IAT is to provide refugees with a coherent framework that assists in making sense of their experiences and their emotional and interpersonal reactions to the challenges they confront within the family and community context. As such, the principles of a general model (ADAPT) are used as a springboard for making concrete, manageable and meaningful life changes at the individual level, a potentially novel approach for psychosocial interventions in the field.

First molecular identification of two Leptospira species (Leptospira interrogans and Leptospira wolffii) in Bangladesh.

Leptospiral 16S rRNA genes were detected in 13 blood samples from 74 febrile patients in north-central Bangladesh, and their sequences phylogenetically clustered with those of Leptospira interrogans or Leptospira wolffii. Genetic diversity in O-antigen polymerase (wzy) was found in an L. interrogans sample.

Prenatal nutrition among rural Bangladeshi pregnant women.

The expected outcome of pregnancy is a healthy mother with a healthy child. The single most important care which could prevent the negative outcomes of pregnancy is Antenatal Care (ANC). Proper and timely antenatal care can significantly reduce the risks of maternal mortality. In pregnancy, total cost is about 80,000 Kcal, and above normal energy requirements. To find out prenatal nutrition an exploratory study was carried out in seven villages of the Ward-2 of Jamtoil Union of Kamarkhand Upazila under Sirajganj District. Thirty pregnant women of different trimesters, gravida and parity had been studied employing the methods and techniques of "Ethnographic Field Work." Mean daily calorie consumption of the Key Informants (KIs) was 1480.49 Kcal without reference to their religious affiliation, family resource base, education, occupation, gravidity, parity and duration of pregnancy. This is indicated that the mean calorie intake of the Key Informants did not meet not only their prenatal nutritional need but also their requirement during pre-pregnancy period. It was observed that food intake was in no way different from that of the non-pregnant status. Antenatal care of rural inhabitants analyzed almost exclusively from biomedical perspectives, its cultural, socio-economic, gender, ecological and other relevant perspectives are mostly ignored. In order to have safe motherhood up through compliance of prenatal advice, nutritional one in particular, these factors should be taken into consideration.

Association between morphological changes of nail and nail arsenic level in patients with arsenicosis.

This case-control type of analytical study was conducted in the Department of Dermatology and Venereology, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh to find out the association between morphological changes of nail and nail arsenic level in arsenicosis patients. Majority of arsenicosis patients were male (56.67%). The mean age of the cases was 43.07+/-13.73 years. Nail changes were found in 26.67% of cases, most were nail dystrophy (23.33%) and rest were Mee's line (3.34%). There was significant difference between cases with or without nail changes and nail arsenic level. But cases with or with out nail changes had a significant difference between duration of intake of arsenic contaminated water. There was no correlation between nail changes and nail arsenic level for nail dystrophy and Mee's line. The study result failed to establish association between the morphological changes of nail and nail arsenic level.

Fixed drug eruptions due to cotrimoxazole.

This prospective study on Fixed Drug Eruption (FDE) was carried out between January 2003 to December 2006 in Dermatology department of Mymensingh Medical College Hospital & private chambers. This study was carried out with an objective to see the specific site of involvement and other clinical parameters in FDE due to cotrimoxazole. In each case, a detailed history was taken and a thorough physical examination was done by at least one dermatologist. Patients with suspected FDE, who had consented, were included in the study. Oral re-challenge test was done in each case after written or verbal consent of the patient or legal guardian. For oral re-challenge, usually half of the usual therapeutic dose of the suspected drug (s) was given first and reactions were observed and if no reaction, then full therapeutic dose was given and then again reactions were observed. In case of no reaction to one drug, the next drug was tested after 2 to 7 days. Age & sex distribution, number of attacks of FDE, number of lesions, distribution of sites of involvement were determined in each case of FDE. All informations were recorded in pre-tested data sheet. Among 93 patients of suspected FDE, 61 patients were confirmed as FDE with identified causes, of which 36 cases were due to cotrimoxazole (59.02%). Age range of patients was from 5 years to 65 years with mean of 24.92 years. Male was predominantly affected (M:F=6.2:1). In 50% cases presenting attack was the 2nd attack. Rest 50% had 3 to more than 10 attacks. Number of lesions was: 2-5 lesions in 50%, solitary lesion in 16.67%, 6-10 lesions in 13.89% and more than 10 lesions in 19.44% cases. Sites of involvement in cases of FDE due to cotrimoxazole (n=36) were as follows: lips 58.33%, genitalia 33.33%, oral 13.89%, trunk 38.89%, limbs 55.56%, hands 16.67%, feet 19.44%, face 19.44% and conjunctiva 2.78%.

Unusual presentation of progressive systemic sclerosis.

A female 38 years old, housewife, presented to the Department of Dermatology and Venereology, Mymensingh Medical College Hospital (MMCH) on 08.04.07 with the complaints of i) pain and reduced movement of hand, knee, shoulder and neck joints for 1 year and 9 months ii) tightness of skin over face, neck, limbs and trunk for 1 year and 6 months iii) patchy depigmentation over same areas for 1 year and 3 months iv) deformity of hands with flexion contractures for 6 months and v) dysphagia to solid food for 3 months. She had no complaints of Raynaud's phenomenon. On general examination, she was ill looking, anemic and nutritionally poor. Examination of integumentary system showed smooth, shiny, thick, hard and hidebound skin with pigmentary alteration of 'salt and pepper' appearance over fingers, hands, limbs, face, neck and trunk. Hands appear claw like but more on the right side than the left and there were no other obvious changes suggestive of digital ischaemia (atrophy, ulceration, scarring, gangrene etc). Face has got suggestive features of scleroderma. Examination of the respiratory system showed restriction of chest movement and reduced expansibility of chest wall. No other abnormality was found on examination of other systems. Laboratory investigations showed histopathology typical of scleroderma. X-ray of hands and feet showed suggestive changes, lung function test-showed restrictive lung disease. Barium swallow x-ray of esophagus in supine position showed mild dilation of lower oesophagus. But serology was non-reactive (negative ANA, Negative RA test, Negative VDRL). So, she was diagnosed as a case of progressive systemic sclerosis (PSS) with some atypicality.

Arsenic accumulation in rice (Oryza sativa L.): human exposure through food chain.

Although human exposure to arsenic is thought to be caused mainly through arsenic-contaminated underground drinking water, the use of this water for irrigation enhances the possibility of arsenic uptake into crop plants. Rice is the staple food grain in Bangladesh. Arsenic content in straw, grain and husk of rice is especially important since paddy fields are extensively irrigated with underground water having high level of arsenic concentration. However, straw and husk are widely used as cattle feed. Arsenic concentration in rice grain was 0.5+/-0.02 mg kg(-1) with the highest concentrations being in grains grown on soil treated with 40 mg As kg(-1) soil. With the average rice consumption between 400 and 650 g/day by typical adults in the arsenic-affected areas of Bangladesh, the intake of arsenic through rice stood at 0.20-0.35 mg/day. With a daily consumption of 4 L drinking water, arsenic intake through drinking water stands at 0.2mg/day. Moreover, when the rice plant was grown in 60 mg of As kg(-1) soil, arsenic concentrations in rice straw were 20.6+/-0.52 at panicle initiation stage and 23.7+/-0.44 at maturity stage, whereas it was 1.6+/-0.20 mg kg(-1) in husk. Cattle drink a considerable amount of water. So alike human beings, arsenic gets deposited into cattle body through rice straw and husk as well as from drinking water which in turn finds a route into the human body. Arsenic intake in human body from rice and cattle could be potentially important and it exists in addition to that from drinking water. Therefore, a hypothesis has been put forward elucidating the possible food chain pathways through which arsenic may enter into human body.

Mixed micellar nanoparticle of amphotericin B and poly styrene-block-poly ethylene oxide reduces nephrotoxicity but retains antifungal activity.

Mixed micellar nanoparticle consisting of amphotericin B (AmB) and poly styrene-block-poly ethylene oxide (PS-block-PEO) was prepared by high pressure homogenizer. Nephrotoxicity of the nanoparticle was investigated along with antifungal activity and self-aggregation status of the drug in the nanoparticle. Nephrotoxicity was markedly reduced when AmB was intravenously administered to rats as mixed micellar nanoparticle with PS-block-PEO in terms of transmission electron microscopy of tubular cells and creatinine clearance. Antifungal activity of AmB was not altered when the drug was in the form of mixed micellar nanoparticle compared to both conventional formulation and AmB micelle treated by same procedure without PS-block-PEO. Self-aggregation status of AmB molecules revealed monomeric in the mixed micellar nanoparticle with PS-block-PEO up to the therapeutic level of the drug (1-3 mM). The reduced nephrotoxicity of AmB in mixed micellar nanoparticle may be associated with the existence of the drug as monomeric form in the nanoparticle. Based on our result, formulation of AmB as mixed micellar nanoparticle with PS-block-PEO may be a promising alternative for the treatment of fungal diseases in patients who are at risk of renal dysfunction.

Accumulation of arsenic in tissues of rice plant (Oryza sativa L.) and its distribution in fractions of rice grain.

A study was conducted to investigate the accumulation and distribution of arsenic in different fractions of rice grain (Oryza sativa L.) collected from arsenic affected area of Bangladesh. The agricultural soil of study area has become highly contaminated with arsenic due to the excessive use of arsenic-rich underground water (0.070+/-0.006 mg l(-1), n=6) for irrigation. Arsenic content in tissues of rice plant and in fractions of rice grain of two widely cultivated rice varieties, namely BRRI dhan28 and BRRI hybrid dhan1, were determined. Regardless of rice varieties, arsenic content was about 28- and 75-folds higher in root than that of shoot and raw rice grain, respectively. In fractions of parboiled and non-parboiled rice grain of both varieties, the order of arsenic concentrations was; rice hull>bran-polish>brown rice>raw rice>polish rice. Arsenic content was higher in non-parboiled rice grain than that of parboiled rice. Arsenic concentrations in parboiled and non-parboiled brown rice of BRRI dhan28 were 0.8+/-0.1 and 0.5+/-0.0 mg kg(-1) dry weight, respectively while those of BRRI hybrid dhan1 were 0.8+/-0.2 and 0.6+/-0.2 mg kg(-1) dry weight, respectively. However, parboiled and non-parboiled polish rice grain of BRRI dhan28 contained 0.4+/-0.0 and 0.3+/-0.1 mg kg(-1) dry weight of arsenic, respectively while those of BRRI hybrid dhan1 contained 0.43+/-0.01 and 0.5+/-0.0 mg kg(-1) dry weight, respectively. Both polish and brown rice are readily cooked for human consumption. The concentration of arsenic found in the present study is much lower than the permissible limit in rice (1.0 mg kg(-1)) according to WHO recommendation. Thus, rice grown in soils of Bangladesh contaminated with arsenic of 14.5+/-0.1 mg kg(-1) could be considered safe for human consumption.

Simultaneous occurrence of multiple types of cutaneous tuberculosis (TVC and PNT) with internal organ tuberculosis (PTB).

A 40 years old male patient of poor socioeconomic condition presented with a well circumscribed rough surfaced and fissured, verrucous plaque on left axilla and a similar lesion on right foot- which were clinically diagnosed as tuberculosis verrucosa cutis. He also had necrotic papular eruption with varioliform scarring in some lesions on upper back clinically diagnosed as papulonecrotic tuberculid. He had fever and cough and mild weight loss suspicious of pulmonary tuberculosis. On investigation ESR was raised, mild anaemia was present, MT was strongly positive, chest x-ray was suggestive of tuberculosis. So, he was diagnosed as a case of simultaneous occurrence of tuberculosis verrucosa cutis (TVC) with papulonecrotic tuberculid (PNT) with pulmonary tuberculosis (PTB). Standard anti tuberculosis chemotherapy already started to offer cure of all lesions.

Effect of arsenic on photosynthesis, growth and yield of five widely cultivated rice (Oryza sativa L.) varieties in Bangladesh.

A glass house experiment was conducted to investigate the effect of soil arsenic on photosynthetic pigments, chlorophyll-a and -b, and their correlations with rice yield and growth. The experiment was designed with three replications of six arsenic treatments viz. control, 10, 20, 30, 60, 90 mg of As kg(-1) soil. Arsenic concentration in initial soil, to which the above mentioned concentrations of arsenic were added, was 6.44+/-0.24 mg kg(-1). Both chlorophyll-a and -b contents in rice leaf decreased significantly (p<0.05) with the increase of soil arsenic concentrations. No rice plant survived up to maturity stage in soil treated with 60 and 90 mg of As kg(-1). The highest chlorophyll-a and -b contents were observed in control treatment (2.62+/-0.24 and 2.07+/-0.14 mg g(-1) were the average values of chlorophyll-a and -b, respectively of the five rice varieties) while 1.50+/-0.20 and 1.04+/-0.08 mg g(-1) (average of five rice varieties) of chlorophyll-a and -b, respectively were the lowest. The content of photosynthetic pigments in these five rice varieties did not differ significantly (p>0.05) from each other in control treatment though they differed significantly (p<0.05) from each other in 30 mg of As kg(-1) soil treatment. Among the five rice varieties, chlorophyll content in BRRI dhan 35 was found to be mostly affected with the increase of soil arsenic concentration while BRRI hybrid dhan 1 was least affected. Well correlations were observed between chlorophyll content and rice growth and yield suggesting that arsenic toxicity affects the photosynthesis which ultimately results in the reduction of rice growth and yield.

Influence of cooking method on arsenic retention in cooked rice related to dietary exposure.

Arsenic concentration in raw rice is not only the determinant in actual dietary exposure. Though there have been many reports on arsenic content in raw rice and different tissues of rice plant, little is known about arsenic content retained in cooked rice after being cooked following the traditional cooking methods employed by the people of arsenic epidemic areas. A field level experiment was conducted in Bangladesh to investigate the influence of cooking methods on arsenic retention in cooked rice. Rice samples were collected directly from a severely arsenic affected area and also from an unaffected area, to compare the results. Rice was cooked according to the traditional methods employed by the population of subjected areas. Arsenic concentrations were 0.40+/-0.03 and 0.58+/-0.12 mg/kg in parboiled rice of arsenic affected area, cooked with excess water and 1.35+/-0.04 and 1.59+/-0.07 mg/kg in gruel for BRRI dhan28 and BRRI hybrid dhan1, respectively. In non-parboiled rice, arsenic concentrations were 0.39+/-0.04 and 0.44+/-0.03 mg/kg in rice cooked with excess water and 1.62+/-0.07 and 1.74+/-0.05 mg/kg in gruel for BRRI dhan28 and BRRI hybrid dhan1, respectively. Total arsenic content in rice, cooked with limited water (therefore gruel was absorbed completely by rice) were 0.89+/-0.07 and 1.08+/-0.06 mg/kg (parboiled) and 0.75+/-0.04 and 1.09+/-0.06 mg/kg (non-parboiled) for BRRI dhan28 and BRRI hybrid dhan1, respectively. Water used for cooking rice contained 0.13 and 0.01 mg of As/l for contaminated and non-contaminated areas, respectively. Arsenic concentrations in cooked parboiled and non-parboiled rice and gruel of non-contaminated area were significantly lower (p<0.01) than that of contaminated area. The results imply that cooking of arsenic contaminated rice with arsenic contaminated water increases its concentration in cooked rice.

Synthesis of decapeptide of L-aspartic acid and benzyl-L-aspartic acid by solid phase peptide synthesis.

Polyene macrolide amphotericin B (AmB) is the drug of choice for the treatment of disseminated fungal infections. However, because of its pronounced side effects, the drug has limited applicability. There are few interesting reports, which state that co-administration of the drug with homo-peptide of polyaspartic acid reduces the side effects of the drug. In our present study, an approach has been made to systematically synthesize low molecular weight heteropeptides consisting of L-aspartic acid and its derivative. It was hypothesized that such heteropeptides will reduce the toxic side effects of the drug by facile hydrophobic binding between the polymer and the drug. We have employed the strategy of solid phase peptide synthesis (SPPS) to synthesize low molecular weight hetero-peptides by using L-aspartic acid and benzyl-L-aspartic acid to induce the hydrophobic binding between the peptide and the drug. In future, the proposed methodology can be employed to tailor other polypeptides substituted with benzyl groups to reduce the nephrotoxicity of AmB.