32 research outputs found
The triphenylmethane dye brilliant blue G is only moderately effective at inhibiting amyloid formation by human amylin or at disaggregating amylin amyloid fibrils, but interferes with amyloid assays; Implications for inhibitor design.
The development of inhibitors of islet amyloid formation is important as pancreatic amyloid deposition contributes to type-2 diabetes and islet transplant failure. The Alzheimer's Aβ peptide and human amylin (h-amylin), the polypeptide responsible for amyloid formation in type-2 diabetes, share common physio-chemical features and some inhibitors of Aβ also inhibit amyloid formation by h-amylin and vice versa. Thus, a popular and potentially useful strategy to find lead compounds for anti-amylin amyloid agents is to examine compounds that have effects on Aβ amyloid formation. The triphenylmethane dye, brilliant blue G (BBG, Sodium;3-[[4-[(E)-[4-(4-ethoxyanilino)phenyl]-[4-[ethyl-[(3-sulfonatophenyl)methyl]azaniumylidene]-2-methylcyclohexa-2,5-dien-1-ylidene]methyl]-N-ethyl-3-methylanilino]methyl]benzenesulfonate) has been shown to modulate Aβ amyloid formation and inhibit Aβ induced toxicity. However, the effects of BBG on h-amylin have not been examined, although other triphenylmethane derivatives inhibit h-amylin amyloid formation. The compound has only a modest impact on h-amylin amyloid formation unless it is added in significant excess. BBG also remodels preformed h-amylin amyloid fibrils if added in excess, however BBG has no significant effect on h-amylin induced toxicity towards cultured β-cells or cultured CHO-T cells except at high concentrations. BBG is shown to interfere with standard thioflavin-T assays of h-amylin amyloid formation and disaggregation, highlighting the difficulty of interpreting such experiments in the absence of other measurements. BBG also interferes with ANS based assays of h-amylin amyloid formation. The work highlights the differences between inhibition of Aβ and h-amylin amyloid formation, illustrates the limitation of using Aβ inhibitors as leads for h-amylin amyloid inhibitors, and reinforces the difficulties in interpreting dye binding assays of amyloid formation
Role of credit in maize (Zea mays L.) production and assessment of food security in a selected area of Bangladesh
Credit provides the means for many farmers to adjust their operations to keep up with the constant changes and, by doing so, to improve their operations. It also contributes to achieve food security of households. Tabular method is used to analyze credit profile, multiple regression analyses are used to determine the impact of credit on maize production and “Modified” OECD scale is used to measure calorie intake level of the 60 maize farming households who has got agricultural credit from Rajshahi Krishi Unnayan Bank in Lalmonirhat district of Bangladesh. Data were collected through field survey by using pre-designed and pre-tested interview schedule. TK.10500, 26333.33, 92103.77 (US 59553.57) and at 9% interest it became TK. 54, 52,725 (US$ 64913.39). The repayment performance of the households was about 100%. It is also revealed from the study that credit had a positive impact on fertilizer demand and irrigation demand and overall a positive impact on maize production. The coefficient of maize production with respect to agricultural credit was 0.081. The elasticity of fertilizer and irrigation demand with respect to credit was 0.016 and 0.543 respectively. The calorie intake situation of the sample households depicts that about 6.67% of the respondents belonged to the ultra-poor whose per day calorie intake was 1481.991 k.cal. About 20% of respondents were hardcore poor whose per day calorie intake was 1722.133 k.cal. The persons belonged to the absolute poor about 21.67% and per capita calorie intake was 1934.605 k.cal. The rest 51.67% belonged to the non-poor group. Different financial institutions should disburse sufficient agricultural credit to fulfill the requirement of the farmers
ANTIHYPERGLYCAEMIC AND ANTINOCICEPTIVE ACTIVITY EVALUATION OF METHANOLIC EXTRACT OF WHOLE PLANT OF AMARANTHUS TRICOLOUR L. (AMARANTHACEAE)
Amaranthus tricolor whole plants are used by folk medicinal practitioners of Bangladesh for treatment of pain, anaemia, dysentery, skin diseases, diabetes, and as a blood purifier. Thus far, no scientific studies have evaluated the antihyperglycaemic and antinociceptive effects of the plant. The present study was carried out to evaluate the possible glucose tolerance efficacy of methanolic extracts of A. tricolour whole plants using glucose-induced hyperglycaemic mice, and antinociceptive effects with acetic acid-induced gastric pain models in mice. In antihyperglycaemic activity tests, the extract at different doses was administered one hour prior to glucose administration and blood glucose level was measured after two hours of glucose administration (p.o.) using glucose oxidase method. The statistical data indicated the significant oral hypoglycaemic activity on glucose-loaded mice at all doses of the extracts tested. Maximum antihyperglycaemic activity was shown at 400 mg extract per kg body weight, which was comparable to that of a standard drug, glibenclamide (10 mg/kg body weight). In antinociceptive activity tests, the extract also demonstrated a dose-dependent significant reduction in the number of writhings induced in mice through intraperitoneal administration of acetic acid. Maximum antinociceptive activity was observed at a dose of 400 mg extract per kg body weight, which compared favourably with that of a standard antinociceptive drug, aspirin, when administered at a dose of 200 mg per kg body weight. The results validate the folk medicinal use of the plant for reduction of blood sugar in diabetic patients as well as the folk medicinal use for alleviation of pain. The results suggest that this plant may possess further potential for scientific studies leading to possible discovery of efficacious antihyperglycaemic and antinociceptive components
Molecular detection of atypical microorganisms in patients with ventilator associated pneumonia
Ventilator-associated pneumonia (VAP) is one of the major causes of morbidity and mortality among the critically ill patients of intensive care units (ICU). The present cross sectional study was conducted to isolate and identify bacterial causes of VAP among the patients admitted in intensive care unit (ICU) of Dhaka Medical College Hospital. The study was conducted between July, 2013 to June 2014. A total of 65 endotracheal aspirate (ETA) and blood samples were collected from patients with clinically suspected ventilator associated peumonia(VAP). Samples were collected from patients on mechanical ventilation for more than 48 hours. ETA and blood samples were cultured aerobically. Multiplex PCR was performed with ETA to detect Mycoplasma pneumoniae, Legionella pneumophila and Chlamydia pneumoniae. Among the atypical bacteria, M. pneumoniae were detected in 5 (7.69%), L. pneumophila in 4 (6.15%) cases by multiplex PCR in ETA from VAP cases. No C. pneumoniae was detected. The study revealed that in VAP cases atypical bacteria should be considered as a possible bacterial agents.
Ibrahim Med. Coll. J. 2015; 9(1): 22-2
Differential effects of serine side chain interactions in amyloid formation by islet amyloid polypeptide
Islet amyloid polypeptide (IAPP), a 37 residue polypeptide, is the main protein component of islet amyloid deposits produced in the pancreas in Type 2 diabetes. Human IAPP contains five serine residues at positions 19, 20, 28, 29, and 34. Models of the IAPP amyloid fibril indicate a structure composed of two closely aligned columns of IAPP monomers with each monomer contributing to two intermolecular β-strands. Ser 19 and Ser 20 are in the partially ordered β-turn region, which links the two strands, whereas Ser 28, Ser 29, and Ser 34 are in the core region of the amyloid fibril. Ser 29 is involved in contacts between the two columns of monomers and is the part of the steric zipper interface. We undertook a study of individual serine substitutions with the hydrophobic isostere 2-aminobutyric acid (2-Abu) to examine the site-specific role of serine side chains in IAPP amyloid formation. All five variants formed amyloid. The Ser 19 to 2-Abu mutant accelerates amyloid formation by a factor of 3 to 4, while the Ser 29 to 2-Abu mutation modestly slows the rate of amyloid formation. 2-Abu replacements at the other sites had even smaller effects. The data demonstrate that the cross-column interactions made by residue 29 are not essential for amyloid formation and also show that cross-strand networks of hydrogen-bonded Ser side chains, so called Ser-ladders, are not required for IAPP amyloid formation. The effect of the Ser 19 to 2-Abu mutant suggests that residues in this region are important for amyloid formation by IAPP
The triphenylmethane dye brilliant blue G is only moderately effective at inhibiting amyloid formation by human amylin or at disaggregating amylin amyloid fibrils, but interferes with amyloid assays; Implications for inhibitor design.
The development of inhibitors of islet amyloid formation is important as pancreatic amyloid deposition contributes to type-2 diabetes and islet transplant failure. The Alzheimer's Aβ peptide and human amylin (h-amylin), the polypeptide responsible for amyloid formation in type-2 diabetes, share common physio-chemical features and some inhibitors of Aβ also inhibit amyloid formation by h-amylin and vice versa. Thus, a popular and potentially useful strategy to find lead compounds for anti-amylin amyloid agents is to examine compounds that have effects on Aβ amyloid formation. The triphenylmethane dye, brilliant blue G (BBG, Sodium;3-[[4-[(E)-[4-(4-ethoxyanilino)phenyl]-[4-[ethyl-[(3-sulfonatophenyl)methyl]azaniumylidene]-2-methylcyclohexa-2,5-dien-1-ylidene]methyl]-N-ethyl-3-methylanilino]methyl]benzenesulfonate) has been shown to modulate Aβ amyloid formation and inhibit Aβ induced toxicity. However, the effects of BBG on h-amylin have not been examined, although other triphenylmethane derivatives inhibit h-amylin amyloid formation. The compound has only a modest impact on h-amylin amyloid formation unless it is added in significant excess. BBG also remodels preformed h-amylin amyloid fibrils if added in excess, however BBG has no significant effect on h-amylin induced toxicity towards cultured β-cells or cultured CHO-T cells except at high concentrations. BBG is shown to interfere with standard thioflavin-T assays of h-amylin amyloid formation and disaggregation, highlighting the difficulty of interpreting such experiments in the absence of other measurements. BBG also interferes with ANS based assays of h-amylin amyloid formation. The work highlights the differences between inhibition of Aβ and h-amylin amyloid formation, illustrates the limitation of using Aβ inhibitors as leads for h-amylin amyloid inhibitors, and reinforces the difficulties in interpreting dye binding assays of amyloid formation