Endotoxins of Enteric Pathogens Are Chemotactic Factors for Human Neutrophils

Islam, Laila N.,Nabi, A.H.M. Nurun,Ahmed, K. Mokim,Sultana, Novera Korean Society for Biochemistry and Molecular Biol 2002 Journal of biochemistry and molecular biology Vol.35 No.5

Early activation of human peripheral blood polymorphonuclear neutrophils is characterized by their morphological changes from spherical to polarized shapes. The endotoxins from enteric pathogens (S. dysenteriae type 1, V. cholerae Inaba 569B, S. typhimurium, and K. pneumoniae) were assessed by their ability to induce morphological polarization of the neutrophils as measures of early activation. Phagocytic activity, adhesion, chemokinetic locomotion, and nitroblue tetrazolium (NBT) dye-reduction ability measured the later activation of the cells. Neutrophils showed distinct morphological polarization in suspension over a wide range of concentrations of these endotoxins when were compared with those that were induced by the standard chemotactic factor, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). It was discovered that all of the endotoxins induced locomotor responses in neutrophils in suspension that were dose- and time-dependent. The optimum concentration for the endotoxins of S. dysenteriae, V. cholerae, and K. pneumoniae was 1 mg/ml in which 71, 69, and 66% of the neutrophils were polarized. However, the S. typhimurium dose was 2 mg/ml in which 50% of the cells responded. Neutrophils that were stimulated with endotoxins also showed increased random locomotion (p<0.005) through cellulose nitrate filters, but an enhanced adhesion of the cells to glass surfaces (p<0.03). These are important functions of these cells to reach and phagocytose damaged cells, as well as invading microorganisms. Interestingly, the endotoxins had a highly-significant inhibitory effect upon the proportions of neutrophils phagocytosing opsonized yeast (p<0.01) with a small number of yeast that were engulfed by the cells (p<0.02). Further, endotoxin-treated cells showed an enhanced ability to reduce NBT dye (p<0.03). Therefore, we concluded that endotoxins of enteric pathogens are neutrophil chemotactic factors.

Endotoxins of Enteric Pathogens Are Chemotactic Factors for Human Neutrophils

(Laila N. Islam),(A. H. M. Nurun Nabi),(K. Mokim Ahmed),(Novera Sultana) 생화학분자생물학회 2002 BMB Reports Vol.35 No.5

Early activation of human peripheral blood polymorphonudear neutrophils is characterized by their morphological changes from spherical to polarized shapes. The endotoxins from enteric pathogens (S. dysenteriae type 1, V cholerae Inaba 569B, S. typhimurium, and K. pneumoniae) were assessed by their ability to induce morphological polarization of the neutrophils as measures of early activation. Phagocytic activity, adhesion, chemokinetic locomotion, and nitroblue tetrazolium (NBT) dyereduction ability measured the later activation of the cells. Neutrophils showed distinct morphological polarization in suspension over a wide range of concentrations of these endotoxins when were compared with those that were induced by the standard chemotactic factor, N-formyl-L-methionyl-L-leucyl-L-phenylalanine (FMLP). It was discovered that all of the endotoxins induced locomotor responses in neutrophils in suspension that were dose- and time-dependent. The optimum concentration for the endotoxins of S. dysenteriae, V. cholerae, and K pneumoniae was 1 mg/ml in which 71, 69, and 66% of the neutrophils were polarized. However, the S. typhimurium dose was 2 mg/ml in which 50% of the cells responded. Neutrophils that were stimulated with endotoxins also showed increased random locomotion (p<0.005) through cellulose nitrate filters, but an enhanced adhesion of the cells to glass surfaces (p<0.03). These are important functions of these cells to reach and phagocytose damaged cells, as well as invading microorganisms. Interestingly, the endotoxins had a highly-significant inhibitory effect upon the proportions of neutrophils phagocytosing opsonized yeast (p<0.01) with a small number of yeast that were engulfed by the cells (p<0.02). Further, endotoxin-treated cells showed an enhanced ability to reduce NBT dye (p<0.03). Therefore, we concluded that endotoxins of enteric pathogens are neutrophil chemotactic factors.

Polymorphonuclear Neutrophil Dysfunctions in Streptozotocin-induced Type 1 Diabetic Rats

Nabi, A.H.M. Nurun,Islam, Laila N.,Rahman, Mohanmmad Mahfuzur,Biswas, Kazal Boron Korean Society for Biochemistry and Molecular Biol 2005 Journal of biochemistry and molecular biology Vol.38 No.6

Since conflicting results have been reported on non-specific immune response in type 1 diabetes, this study evaluates polymorphonuclear neutrophil (PMN) functions in the infection free Long Evan diabetic rats (type 1) by using tests that include: polarization assay, phagocytosis of baker's yeasts (Saccharomyces cerevisiae) and nitroblue tetrazolium (NBT) dye reduction. Polarization assay showed that neutrophils from diabetic rats were significantly activated at the basal level compared to those from the controls (p < 0.001). After PMN activation with N-formyl-methionyl-leucyl-phenylalanine (FMLP), control neutrophils were found to be more polarized than those of the diabetic neutrophils and the highest proportions of polarization were found to be 67% and 57% at $10^{-7}\;M$ FMLP, respectively. In the resting state, neutrophils from the diabetic rats reduced significantly more NBT dye than that of the controls (p < 0.001). The percentages of phagocytosis of opsonized yeast cells by the neutrophils from control and diabetic rats were 87% and 61%, respectively and the difference was statistically significant (p < 0.001). Evaluation of the phagocytic efficiency of PMNs revealed that control neutrophils could phagocytose $381{\pm}17$ whereas those from the diabetic rats phagocytosed $282{\pm}16$ yeast cells, and the efficiency of phagocytosis varied significantly (p < 0.001). Further, both the percentages of phagocytosis and the efficiency of phagocytosis by the diabetic neutrophils were inversely related with the levels of their corresponding plasma glucose (p = 0.02; r = -0.498 and p < 0.05; r = -0.43, respectively), which indicated that increased plasma glucose reduced the phagocytic ability of neutrophils. Such relationship was not observed with the control neutrophils. These data clearly indicate that PMN functions are altered in the streptozotocin (STZ) - induced diabetic rats, and hyperglycemia may be the cause for the impairment of their functions leading to many infectious episodes.

Aspects of Structural and Multiferroic Properties of A- (15% Gd) and B-Site (5–15% Cr) Doped Perovskite BiFeO3 Nanoparticles

M. N. Hossain,M. A. Matin,M. A. Islam,M. M. Rhaman,M. A. Hakim,M. F. Islam 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.4

This report focuses on the investigation of multiferroic properties of 15% Gd and (5–15) % Cr co-doped Bismuth Ferrite (BFO) nanoparticles prepared by sol–gel method. The synthesized pure BFO has shown to be R3c rhombohedral crystal structure which partially transforms to Pnma orthorhombic crystal structure with increasing Cr dopant in co-doped samples. The crystallite size was found to vary from 68 to 22 nm depending on doping level. SEM images exhibited uniform nanoparticles and the average size of particles was shown to vary from 263 to 114 nm which is comparatively higher than that obtained from XRD results due to agglomeration eff ects. Ferroelectric tests exhibited a signifi cant reduction in polarization in doped BFO under an applied fi eld of ± 15 kV/cm. In contrast, the magnetic measurement showed a substantial improvement in ferromagnetic properties of the synthesized samples compared to un-doped one. A prominent exchange anisotropy eff ect was also observed in all the samples at room temperature. In addition, co-doped BFO samples demonstrated a signifi cant reduction in band gap energy from 1.88 to 1.68 eV.

Optical and Ferroelectric Properties of Bi0.95Gd0.05Fe1−xCrxO3

M. A. Matin,M. N. Hossain,M. M. Islam,M. A. Hakim,M. F. Islam 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.3

In this paper, optical and ferroelectric properties were investigated for gadolinium, Gd3+ (5 at.%) and chromium, Cr3+ (0–8at.%) co-doped of BiFeO3 . Chemical solution deposition (CSD) method was employed as compatible device fabrication technology to synthesize Gd and Cr co-doped multiferroic BiFeO3 (Bi0.95Gd0.05Fe1−xCrxO3 with x = 0–0.08). X-ray diffraction (XRD) analysis confirmed a well-defined crystalline phase with a tendency towards structural change from rhombohedral to orthorhombic symmetry. Crystallite size was found to reduce substantially from 34 to 13.5 nm with increasing the doping concentration of Cr3+ . The field emission scanning electron microscopy (FESEM) demonstrated a significant reduction in grain size of doped BiFeO3 compared to un-doped one following the trend obtained from XRD results. Ferroelectric nature of samples was obtained from polarization versus electric field measurements. Improved ferroelectric order was displayed in co-doped BiFeO3 with a maximum remnant polarization of 0.23 μ C∕cm2 . Diffuse reflectance measurement by UV–Vis–NIR spectroscopy of Gd 3+ and Cr3+ co-doped BiFeO3 has shown a significant reduction in the optical band-gap energy (Eg) to 1.71 eV compared to 2.03 eV of pure BiFeO 3 counterpart.

Effect of Variety and Stage of Maturity on Nutritive Value of Whole Crop Rice Silage for Ruminants: In situ Dry Matter and Nitrogen Degradability and Estimation of Metabolizable Energy and Metabolizable Protein

Islam, M.R.,Ishida, M.,Ando, S.,Nishida, T.,Yoshida, N.,Arakawa, M. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.11

The effect of eight varieties of whole crop rice silage (WCRS) harvested at four stages of maturity were investigated for in situ DM and N degradability, ME and MP yield and content in an 8${\times}$4 factorial experiment. The varieties were Akichikara, Fukuhibiki, Habataki, Hamasari, Hokuriku 168, Kusanami, Tamakei 96 and Yumetoiro. Hamasari and Kusanami were forage varieties while all others were grain varieties. Forages were harvested on 10, 22, 34 and 45 days after flowering, ensiled and kept in airtight condition. Between 45 and 49 days after ensiling, silages opened, chopped and milled green to pass through 4 mm screen. Samples were incubated in the rumen of two Holstein steers for 0, 3, 6, 9, 12, 24, 48, 72 and 96 h over eight 4 d periods. Bags at 0 h were washed in a washing machine. Variety affected DM (p<0.001: except 'a+b', p<0.01) and N (p<0.001) degradability characteristics of WCRS. Stages of maturity also affected DM (p<0.001: except 'a+b', p<0.05; 'c', p<0.08) and N (p<0.01: except 'c', p<0.05) degradability characteristics of WCRS. Interactions between variety and stages of maturity occurred in all DM (p<0.001) and N (p<0.001) degradability characteristics except (p>0.05) for DM 'b', DM 'c', DM 'a+b' nd N 'c'. Effective DM degradability was higher in grain varieties than forage varieties and degradability increased with maturity. N availability decreased only slightly with maturity. Variety was the key factor for N degradability characteristics of WCRS since variety accounted for most of the total variation for degradability characteristics. Both ME and MP content and yield were higher (p<0.001) in grain varieties, and they increased (p<0.001) with the maturity. The results clearly demonstrated that the grain type varieties contained higher ME and MP content than forage varieties, and increase in maturity increases both ME and MP content of WCRS.

Estimation of Nutritive Value of Whole Crop Rice Silage and Its Effect on Milk Production Performance by Dairy Cows

Islam, M.R.,Ishida, M.,Ando, S.,Nishida, T.,Yoshida, N. Asian Australasian Association of Animal Productio 2004 Animal Bioscience Vol.17 No.10

The nutritive value and utilization of whole crop rice silage (WCRS), Hamasari, at yellow mature stage was determined by three studies. In first study, chemical composition, in vivo digestibility and metabolizable energy (ME) content of WCRS was determined by Holstein steers. WCRS contains 6.23% CP, its digestibility is 48.4% and estimated TDN is 56.4%. Its ME content was 1.91 Mcal/kg DM. Gross energy (GE) retention (% of GE intake) in steers is only 22.7% most of which was lost through feces (44.7% of GE intake). It takes 81 minutes to chew a kg of WCRS by steers. In another study, the effect of Hamasari at yellow mature stage at three stages of lactation (early, mid and late lactation) and two levels of concentrate (40 or 60%) on voluntary intake, ME content and ME intake, milk yield and composition using lactating Holstein dairy cows were investigated. Total intake increased with the concentrate level in early and mid lactation, but was similar irrespective of concentrate level in late lactation. WCRS intake was higher with 40% concentrate level than with 60% concentrate. ME intake by cows increased with the concentrate level and WCRS in early lactating cows with 40% concentrate can support only 90% of the ME requirement. Milk production in accordance with ME intake increased with the increase in concentrate level in early and mid lactating cows but was similar in late lactating cows irrespective of concentrate level. Fat and protein percent of milk in mid and late lactating cows were higher with for 60% concentrate than 40%, but reverse was in early lactating cows. Solids-not-fat was higher with for 60% concentrate than 40% concentrate. Finally in situ degradability of botanical fractions such as leaf, stem, head and whole WCRS, Hamasari at yellow mature stage was incubated from 0 to 96 h in Holstein steers to determine DM and N degradability characteristics of botanical fractions and whole WCRS. Both DM and N solubility, rate of degradation and effective degradability of leaf of silage was lower, but slowly degradable fraction was higher compared to stem and head. Solubility of DM and N of stem was higher than other fractions. The 48 h degradability, effective degradability and rate of degradation of leaf were always lower than stem or head. In conclusion, voluntary intake of silage ranged from 5 to 12 kg/d and was higher with low levels of concentrate, but milk yield was higher with high levels of concentrate. Fat corrected milk yield ranged from 19 to 37 kg per day. For consistency of milk, early lactating cows should not be allowed more than 40% whole crop rice silage in the diet, but late lactating cows may be allowed 60% whole crop rice silage.

A Bacteriological Assessment for Salmonella and Escherichia coli in Some Selected Fresh Water Prawn (Macrobrachium rosenbergii) Farms and Depots

M. N. Haider,M. Faridullah,M. Kamal,M. N. Islam,M. N. A. Khan 한국해양바이오학회 2007 한국해양바이오학회지 Vol.2 No.1

Biogas production from food waste using semi-continuous anaerobic digester

이슬람 ( M. N. Islam ),윤형선 ( H. S. Yoon ),송형운 ( H. W. Song ),박금주 ( K. J. Park ) 한국농업기계학회 2011 한국농업기계학회 학술발표논문집 Vol.16 No.1

Incineration is not suitable due to the high moisture contents and low heating value of food waste. So, mesophilic anaerobic digestion has been one of the most favorable options for food waste disposal. In this study, the biogas production from food waste was investigated using lab scale semi-continuous stirred tank reactor (SCSTR) at 35℃ with 30d HRT and 30L working volume. The mesophilic digestion test was performed with three different feed materials (food waste) and food to microorganism (F/M) ratios (0.13, 0.34, and 0.27) in the same experiment. The results showed that the F/M ratios significantly affected the biogas production rate. The highest production rate was obtained at F/M ratio of 0.13. Biogas produced in anaerobic digestion consists of 68.7% CH4 and 31.2% CO₂. The average biogas and methane production of digester were 29.96 L/Kg VS day^-1 and 20.58 L/Kg VS day^-1, respectively. The CH₄ could be calculated as the heat energy 1.85 Kcal/Kg VS day^-1. The digestion was operated without addition of chemicals or nutrients into the system.

Effect of Preparation Routes on the Crystal Purity and Properties of BiFeO3 Nanoparticles

M. A. Matin,M. M. Rhaman,M. N. Hossain,F. A. Mozahid,M. A. Hakim,M. H. Rizvi,M. F. Islam 한국전기전자재료학회 2019 Transactions on Electrical and Electronic Material Vol.20 No.6

Sol–gel as a chemical solution deposition technique is compatible with functional device fabrication technology. Single-phase bismuth ferrite (BiFeO3) mutiferroic with its multi-functionality has extensively been studied for a variety of prospective novel device applications. However, the synthesis of BiFeO3 is confronted with a challenge to produce pure state without any secondary phase. Scarcity of unified process parameters impede justifi cation of best synthesis techniques. In this work, sol–gel methods with and without auto-combustion reactions were used to synthesize bismuth ferrite (BiFeO3) nanoparticles. Different techniques UV–Vis–NIR spectroscopy, XRD, EDS, and SEM were used to investigate the effect of preparation routes on the crystal purity and properties of prepared samples. Synthesized nanoparticles were calcined at temperature between 400 and 800 ◦ C and an optimal calcination temperature was found to be 600 ◦ C. Band-gap was determined by UV–Vis–NIR spectroscopy and found to vary from 1.93 to 2.07 eV. X-ray diff raction (XRD) has confi rmed single phase rhombohedral crystal structure with R3c symmetry. Avg crystallite size was found to be higher (40–68 nm) in auto-combustion reaction compared to that of 23–42 nm obtained in sol–gel method without auto-combustion reaction. The band-gap energy was found to reduce with decreasing crystallite size (above the critical size of 10 nm) following Brus’s eff ective mass model. Induced strain was found to exhibit an inverse relation with crystallite size and displayed substantial reduction in auto-combustion reaction route. The microstructural features were investigated by fi eld emission scanning electronic microscopy and avgparticle size was shown to vary from 107 to 197 nm depending on adopted synthesis route. A low reaction temperature (70 ◦ C–80 ◦ C) without auto-combustion and calcination temperature at 600◦ C were found to be optimal conditions for the preparation of low impurity un-doped bismuth ferrite nanaoparticles.