High concentrations (greater than 5 lM) of arsenic trioxide (As 2 O 3) have been reported to be a... more High concentrations (greater than 5 lM) of arsenic trioxide (As 2 O 3) have been reported to be able to induce apoptosis in several malignant cells. We explored cell lines in which apoptosis was induced with a therapeutic concentration (1-2 lM) of As 2 O 3 , and found that 1 lM of As 2 O 3 induced apoptosis in the NKM-1 cell line, which was established from a patient with acute myeloid leukemia (M2). Apoptosis induced by 1 lM of As 2 O 3 in NKM-1 cells was accompanied by an increased cellular content of H 2 O 2 , a decreased mitochondrial membrane potential (Dwm), and activation of caspase-3. C-Junterminal kinase (JNK) was activated only in NKM-1 cells and arsenic-sensitive NB4 cells, but not in arsenic-insensitive HL-60 cells. Activation of JNK in NKM-1 was sustained from 6 to 24 h after As 2 O 3 treatment, and preceded changes in cellular H 2 O 2 , Dwm, and caspase-3 activation. Moreover, addition of a JNK inhibitor reduced the percentage of apoptotic cells after the As 2 O 3 treatment. Taken together, in the M2 cell line NKM-1, 1 lM of As 2 O 3 induced sustained activation of JNK and apoptosis. This finding may provide a basis to select a subgroup other than acute promyelocytic leukemia, which can benefit from As 2 O 3 treatment.
Intercultural operations including weeding were completed according to participatory discussion b... more Intercultural operations including weeding were completed according to participatory discussion between farmers and ITDG Research Assistants. Cobs with straw colour were harvested in Feb-March 2003 and after harvest maize cobs were sun dried for 2-3 days, then threshed mechanically by hand thresher (supported by RARS). Result and discussion: The average production rate was 2.4 tonnes per acre in all three situations. This was a low yield in comparison to standard production rates of other regions in Bangladesh. However, considering the low investment in sub-fertile soil the cost-benefit was reasonable. Maize cultivation appeared viable and valued. Source of quality seed, access to market and credit support were found to be very important issues. Mono-cropped maize was less susceptible to disease and less labour intensive in comparison with intercrop situation of maize and chilli. From farmers' opinions, maize dyke crop situation was better than intercrop situation in terms of yield. Therefore, mono-crop and dike-crop were found to be widely adopted by char land farmers. From farmers' experience, maize cultivation seemed to be profitable compared to other cereal crops like boro rice (gross income Tk3000-4000 per acre), wheat (gross income Tk2500-3000/acre) and millet (gross income Tk1500-2000/acre). Farmers also proposed changes to the traditional cropping pattern as-Traditional cropping pattern
International Journal of Infectious Diseases, 2012
Background: In Honduras, diarrhea is a major cause of pediatric morbidity and mortality. Worldwid... more Background: In Honduras, diarrhea is a major cause of pediatric morbidity and mortality. Worldwide, rotaviruses have consistently emerged as the single most important etiologic agent in infants and young children although other viruses such as norovirus and astrovirus have also been shown to be responsible for acute diarrhea among children in their first years of life. Unfortunately, there is limited information in the country concerning the etiologic role of these agents in acute gastroenteritis. Objective: To investigate the prevalence and to determine the genotypes and epidemiological characteristics of three of the major enteropathogenic virusesgroup A rotavirus, norovirus and human astrovirus-in preschool children. Methods: Between October 2010 and July 2011, fecal samples and their corresponding epidemiological data were collected from children under five years of age with acute diarrhea in three health care centers in Tegucigalpa, Honduras. Immunochromatographic and immunoenzymatic assays were applied to all samples to screen for rotavirus group A and astrovirus, respectively. Molecular characterization of the rotavirus-positive samples was done using reverse transcriptase polymerase chain reaction (RT-PCR) and genotyping assays. RT-PCR was also applied to confirm astrovirus positivity and to detect norovirus, followed by sequencing to assign their genotypes. Results: Of the 100 fecal samples collected, at least one viral agent was detected in 31% of the children. The prevalence of rotavirus, norovirus and astrovirus was 14%, 13% and 5%, respectively. The most frequent rotavirus type identified was G2P[4] occurring in 93% of cases. Of 13 norovirus positive samples, all belonged to genogroup II, being GII.4 and GII.2 the most common. Human astrovirus were clustered into three different genotypes: HAstV-1, HAstV-2 and HAstV-8. One sample showed co-infection with norovirus and human astrovirus. Conclusion: This comprehensive molecular characterization and epidemiological knowledge of enteric viruses in Tegucigalpa demonstrate the wide diversity of circulating genotypes of these agents, and describe for the first time that norovirus and human astrovirus are causatives agents of acute gastroenteritis in children in the country, suggesting that more extensive studies in infantile population are needed in Honduras for the development of efficient preventive measures.
You may download, copy and otherwise use the AAM for non-commercial purposes provided that your l... more You may download, copy and otherwise use the AAM for non-commercial purposes provided that your license is limited by the following restrictions: (1) You may use this AAM for non-commercial purposes only under the terms of the CC-BY-NC-ND license. (2) The integrity of the work and identification of the author, copyright owner, and publisher must be preserved in any copy.
Redistribution of arsenic (As) during silicidation of a 13-nm Ni film on an n1/p junction at 450°... more Redistribution of arsenic (As) during silicidation of a 13-nm Ni film on an n1/p junction at 450°C is investigated. NiSi formation is observed by x-ray dif-fraction, micro-Raman scattering spectroscopy, and Rutherford backscatter-ing spectroscopy (RBS). Both secondary ion ...
A simple, fast and economic reversed phase high performance liquid chromatographic (RP-HPLC) meth... more A simple, fast and economic reversed phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated for simultaneous and quantitative analyses of pioglitazone HCl and glimepiride in pharmaceutical dosage forms. The method was developed using the mobile phase comprising of potassium dihydrogen phosphate buffer (KH 2 PO 4) at pH 3.4 and acetonitrile in the ratio of 40:60 (v/v) over C-18 bonded silica column (250 x 4.6 mm, 5 um, Phenomenex Inc.) at ambient temperature. The flow rate was at 0.8 min/min and the eluent was monitored by UV detection at 235 nm. The recoveries were found to be >97% for pioglitazone and >99% for glimepiride, demonstrative of accuracy of the protocol. Inter-day and intra-day precision of the new method were less than the maximum allowable limit (RSD% ≤ 2.0) according to ICH, USP and FDA guidelines. The method showed linear response with correlation coefficient (r 2) values of 0.9991 for pioglitazone and 0.9999 for glimepiride. Therefore, the method was found to be accurate, reproducible, sensitive and less time consuming and can be successfully applied for the assay of pioglitazone and glimepiride in combined formulations.
ABSTRACT Arsenic contamination of groundwaters in the floodplain of the Ganges–Meghna river syste... more ABSTRACT Arsenic contamination of groundwaters in the floodplain of the Ganges–Meghna river system can represent a serious threat to human health and to the sustainability of irrigated rice cultivation. The extent of As accumulation in the soils irrigated with As-containing groundwater seems to vary among different study areas and the relationships between the pedoenvironmental conditions and As fixation/mobilization are not yet completely elucidated. This work was aimed to assess how soil and environmental properties interact in affecting the fixation/mobilization of As in the soils of the Ganges and Meghna agricultural zones. For this purpose, soil samples from different districts in the Ganges and Meghna floodplains have been characterized, different pools of As, Fe, Mn and P have been quantified and the results have been related to the main soil and environmental characteristics of the two areas. The As content in groundwater and the baseline As concentration in the parent material in the two zones would point to a higher As accumulation in the Meghna floodplain soils, however the Ganges floodplain soils had higher contents of As in all fractions, proving the key role of the factors controlling the release/fixation of As. The soils of the two floodplains, in fact, differed for most physicochemical properties. The ones from the Ganges floodplain were calcareous, with finer texture and generally richer in Fe but oxalate extractable Fe was higher in the Meghna floodplain soils, suggesting a higher degree of waterlogging. This is in agreement with the averagely longer duration and higher depth of submersion of the soils of this area, which enhanced Fe dynamics and favored the release of the less tightly bonded As forms. The competing effect of P was probably similar in the two areas, since P concentrations did not differ significantly among the two soil series. However, more P was Olsen extractable in the Meghna floodplain soils, in contrast with As, that was more easily extracted from the Ganges floodplain soils. The concentration and potential mobility of the retained As were hence greater in the soils of the Ganges floodplain.
High concentrations (greater than 5 lM) of arsenic trioxide (As 2 O 3) have been reported to be a... more High concentrations (greater than 5 lM) of arsenic trioxide (As 2 O 3) have been reported to be able to induce apoptosis in several malignant cells. We explored cell lines in which apoptosis was induced with a therapeutic concentration (1-2 lM) of As 2 O 3 , and found that 1 lM of As 2 O 3 induced apoptosis in the NKM-1 cell line, which was established from a patient with acute myeloid leukemia (M2). Apoptosis induced by 1 lM of As 2 O 3 in NKM-1 cells was accompanied by an increased cellular content of H 2 O 2 , a decreased mitochondrial membrane potential (Dwm), and activation of caspase-3. C-Junterminal kinase (JNK) was activated only in NKM-1 cells and arsenic-sensitive NB4 cells, but not in arsenic-insensitive HL-60 cells. Activation of JNK in NKM-1 was sustained from 6 to 24 h after As 2 O 3 treatment, and preceded changes in cellular H 2 O 2 , Dwm, and caspase-3 activation. Moreover, addition of a JNK inhibitor reduced the percentage of apoptotic cells after the As 2 O 3 treatment. Taken together, in the M2 cell line NKM-1, 1 lM of As 2 O 3 induced sustained activation of JNK and apoptosis. This finding may provide a basis to select a subgroup other than acute promyelocytic leukemia, which can benefit from As 2 O 3 treatment.
Intercultural operations including weeding were completed according to participatory discussion b... more Intercultural operations including weeding were completed according to participatory discussion between farmers and ITDG Research Assistants. Cobs with straw colour were harvested in Feb-March 2003 and after harvest maize cobs were sun dried for 2-3 days, then threshed mechanically by hand thresher (supported by RARS). Result and discussion: The average production rate was 2.4 tonnes per acre in all three situations. This was a low yield in comparison to standard production rates of other regions in Bangladesh. However, considering the low investment in sub-fertile soil the cost-benefit was reasonable. Maize cultivation appeared viable and valued. Source of quality seed, access to market and credit support were found to be very important issues. Mono-cropped maize was less susceptible to disease and less labour intensive in comparison with intercrop situation of maize and chilli. From farmers' opinions, maize dyke crop situation was better than intercrop situation in terms of yield. Therefore, mono-crop and dike-crop were found to be widely adopted by char land farmers. From farmers' experience, maize cultivation seemed to be profitable compared to other cereal crops like boro rice (gross income Tk3000-4000 per acre), wheat (gross income Tk2500-3000/acre) and millet (gross income Tk1500-2000/acre). Farmers also proposed changes to the traditional cropping pattern as-Traditional cropping pattern
International Journal of Infectious Diseases, 2012
Background: In Honduras, diarrhea is a major cause of pediatric morbidity and mortality. Worldwid... more Background: In Honduras, diarrhea is a major cause of pediatric morbidity and mortality. Worldwide, rotaviruses have consistently emerged as the single most important etiologic agent in infants and young children although other viruses such as norovirus and astrovirus have also been shown to be responsible for acute diarrhea among children in their first years of life. Unfortunately, there is limited information in the country concerning the etiologic role of these agents in acute gastroenteritis. Objective: To investigate the prevalence and to determine the genotypes and epidemiological characteristics of three of the major enteropathogenic virusesgroup A rotavirus, norovirus and human astrovirus-in preschool children. Methods: Between October 2010 and July 2011, fecal samples and their corresponding epidemiological data were collected from children under five years of age with acute diarrhea in three health care centers in Tegucigalpa, Honduras. Immunochromatographic and immunoenzymatic assays were applied to all samples to screen for rotavirus group A and astrovirus, respectively. Molecular characterization of the rotavirus-positive samples was done using reverse transcriptase polymerase chain reaction (RT-PCR) and genotyping assays. RT-PCR was also applied to confirm astrovirus positivity and to detect norovirus, followed by sequencing to assign their genotypes. Results: Of the 100 fecal samples collected, at least one viral agent was detected in 31% of the children. The prevalence of rotavirus, norovirus and astrovirus was 14%, 13% and 5%, respectively. The most frequent rotavirus type identified was G2P[4] occurring in 93% of cases. Of 13 norovirus positive samples, all belonged to genogroup II, being GII.4 and GII.2 the most common. Human astrovirus were clustered into three different genotypes: HAstV-1, HAstV-2 and HAstV-8. One sample showed co-infection with norovirus and human astrovirus. Conclusion: This comprehensive molecular characterization and epidemiological knowledge of enteric viruses in Tegucigalpa demonstrate the wide diversity of circulating genotypes of these agents, and describe for the first time that norovirus and human astrovirus are causatives agents of acute gastroenteritis in children in the country, suggesting that more extensive studies in infantile population are needed in Honduras for the development of efficient preventive measures.
You may download, copy and otherwise use the AAM for non-commercial purposes provided that your l... more You may download, copy and otherwise use the AAM for non-commercial purposes provided that your license is limited by the following restrictions: (1) You may use this AAM for non-commercial purposes only under the terms of the CC-BY-NC-ND license. (2) The integrity of the work and identification of the author, copyright owner, and publisher must be preserved in any copy.
Redistribution of arsenic (As) during silicidation of a 13-nm Ni film on an n1/p junction at 450°... more Redistribution of arsenic (As) during silicidation of a 13-nm Ni film on an n1/p junction at 450°C is investigated. NiSi formation is observed by x-ray dif-fraction, micro-Raman scattering spectroscopy, and Rutherford backscatter-ing spectroscopy (RBS). Both secondary ion ...
A simple, fast and economic reversed phase high performance liquid chromatographic (RP-HPLC) meth... more A simple, fast and economic reversed phase high performance liquid chromatographic (RP-HPLC) method has been developed and validated for simultaneous and quantitative analyses of pioglitazone HCl and glimepiride in pharmaceutical dosage forms. The method was developed using the mobile phase comprising of potassium dihydrogen phosphate buffer (KH 2 PO 4) at pH 3.4 and acetonitrile in the ratio of 40:60 (v/v) over C-18 bonded silica column (250 x 4.6 mm, 5 um, Phenomenex Inc.) at ambient temperature. The flow rate was at 0.8 min/min and the eluent was monitored by UV detection at 235 nm. The recoveries were found to be >97% for pioglitazone and >99% for glimepiride, demonstrative of accuracy of the protocol. Inter-day and intra-day precision of the new method were less than the maximum allowable limit (RSD% ≤ 2.0) according to ICH, USP and FDA guidelines. The method showed linear response with correlation coefficient (r 2) values of 0.9991 for pioglitazone and 0.9999 for glimepiride. Therefore, the method was found to be accurate, reproducible, sensitive and less time consuming and can be successfully applied for the assay of pioglitazone and glimepiride in combined formulations.
ABSTRACT Arsenic contamination of groundwaters in the floodplain of the Ganges–Meghna river syste... more ABSTRACT Arsenic contamination of groundwaters in the floodplain of the Ganges–Meghna river system can represent a serious threat to human health and to the sustainability of irrigated rice cultivation. The extent of As accumulation in the soils irrigated with As-containing groundwater seems to vary among different study areas and the relationships between the pedoenvironmental conditions and As fixation/mobilization are not yet completely elucidated. This work was aimed to assess how soil and environmental properties interact in affecting the fixation/mobilization of As in the soils of the Ganges and Meghna agricultural zones. For this purpose, soil samples from different districts in the Ganges and Meghna floodplains have been characterized, different pools of As, Fe, Mn and P have been quantified and the results have been related to the main soil and environmental characteristics of the two areas. The As content in groundwater and the baseline As concentration in the parent material in the two zones would point to a higher As accumulation in the Meghna floodplain soils, however the Ganges floodplain soils had higher contents of As in all fractions, proving the key role of the factors controlling the release/fixation of As. The soils of the two floodplains, in fact, differed for most physicochemical properties. The ones from the Ganges floodplain were calcareous, with finer texture and generally richer in Fe but oxalate extractable Fe was higher in the Meghna floodplain soils, suggesting a higher degree of waterlogging. This is in agreement with the averagely longer duration and higher depth of submersion of the soils of this area, which enhanced Fe dynamics and favored the release of the less tightly bonded As forms. The competing effect of P was probably similar in the two areas, since P concentrations did not differ significantly among the two soil series. However, more P was Olsen extractable in the Meghna floodplain soils, in contrast with As, that was more easily extracted from the Ganges floodplain soils. The concentration and potential mobility of the retained As were hence greater in the soils of the Ganges floodplain.
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