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The SnO2 was synthesized by precipitation method via tin chloride pentahydrate complexation with diethyldithiocarbamate then, calcined at temperatures 450, 600 and 750 °C and utilized for degradation of Sudan black B (SBB) dye. The calcination temperature 600 °C exhibited better degradation capability. Three light sources like visible, mercury and fluorescent were applied and fluorescent light exposed highest degradation of SBB dye. Degradation of SBB reached 90% with dosage of catalyst 15 mg at neutral pH 7 in 100 min. The 20 mg L−1 concentration of SBB dye was optimized for degradation but the degradation decreased at increased concentration of the dye. Synthesized SnO2 nanoparticles was characterized by SEM, XRD, DLS, EDX, zeta potential and FTIR to know their particles size, surface charge, morphology, structure and elemental composition of prepared nanoparticles. The SBB dye degradation followed pseudo second order kinetic model and Langmuir isotherm model. The impacts of factors were studied through factorial design using 18 experiments run, and interactions among different parameters were noted. [ABSTRACT FROM AUTHOR]

Significant autofluorescence (AF) of renal tissue is one of the major causes restricting the use of immunofluorescent staining. This study aimed at controlling renal tissue AF and testing an effective method for optimizing specific signals. In the present study, we observed emergence of strong AF in all renal cells under different fluorescent channels. Significant concentration-dependent reduction in AF of kidney tissue was observed with the use of sodium borohydride (NaBH4) and Sudan black B (SBB) alone (p < 0.05). Under maximum effective concentration, semi-quantitative analysis revealed that inhibitory effect of SBB on AF was superior to that of NaBH4 (P < 0.01). When the two chemicals were combined, we observed that background can be reduced, and specific staining can be optimized at optimum concentration. Intensity of renal tissue was examined by confocal λ scanning, which showed that peaks were located at the range of approximately 480 − 590 nm and similar to those of flavin and lipofuscin. These results indicated that combined use of NaBH4 and SBB, when targeted at different sources of AF in renal tissue, is the most effective means of reducing background and preserving specificity of fluorescent labels. In addition, this method does not interfere with various steps of immunofluorescence experiments. [ABSTRACT FROM AUTHOR]

During screening for poly-β-hydroxybutyrate (PHB) producing bacteria from distillery effluent sample, six out of 30 isolates comprising of three strains of Alcaligenes sp., two strains of Bacillus sp., and one strain of Pseudomonas sp. were found to accumulate varying levels of intracellular PHB. Amongst the various isolates, Alcaligenes sp. RZS4 was found as the potent PHB-producing organism, accumulating higher amounts of PHB. PHB productivity was further enhanced in the presence of oxygen, nitrogen-limiting conditions, and cloning of PHB synthesizing genes of Alcaligenes sp. RZS 4 into Escherichia coli. A twofold increase in PHB yield was obtained from recombinant E. coli vis-à-vis Alcaligenes sp.; the recombinant E. coli accumulated more PHB in NDMM, produced good amount of PHB in a single-stage cultivation process under both nutrient-rich and nutrient-deficient conditions. Extraction of PHB with acetone-alcohol (1:1) was found as suitable method for optimum extraction of PHB as this mixture selectively extracted PHB without affecting the non-PHB cell mass. PHB extract from recombinant E. coli showed the presence of C-H, =O stretching, =C-H deformation, =C-H, =CH, and =C-O functional groups characteristic of PHB. [ABSTRACT FROM AUTHOR]

Sudan black B (SBB) was used to investigate as the nonionic diazo dye-doped in polymer dispersed liquid crystal (PDLC) display, by polymerization-induced phase separation (PIPS) method. The maximum absorbance, contrast ratio, dichroic ratio and the order parameter of nonionic diazo dye in nemetic host (TL203) were investigated using UV-Vis polarized spectroscopy. The orientation of the dye molecules was controlled by electric field, which enabled the contrast ratio of the dye to be obtained by electrically switching. The change occurring on droplet morphologies and electro-optical properties of PDLC film with the change in contents of Sudan black dye and liquid crystals (LC) contents was investigated. We found an increase in LC droplet sizes with the increase of diazo dye and LC contents. Moreover the addition of small amount of nonionic diazo dye reduced the threshold voltage (V $_{\boldsymbol{\rm th}})$, increased off-state transmittance, enhanced the contrast ratio and decreased the response time of dye-doped PDLC. Additionally the change in transition temperature of LC and changes in LC droplet morphologies with the addition of dye were also observed. Such changes were observed with the images taken by polarized optical microscope (POM). The detail discussions on such behaviours were also made. [ABSTRACT FROM AUTHOR]

Cell adhesion plays a key role during various physiological and pathological processes. Many studies have been performed to understand the interaction of platelets with endothelial cells (ECs) during the past decades. Modulation of their interaction has been shown to be therapeutically useful in thrombotic diseases. Some methods of labeling platelets such as counting and radiolabeling have been applied in the study of the platelets-ECs interaction, but these methods did not obtain full approval. A rapid, simple and sensitive assay for platelets-ECs interaction was developed in this paper. Platelets were labeled with Sudan Black B (SBB) before adding to confluent ECs monolayer. Non-adherent platelets were removed by washing with PBS. The adherent platelets were lysed with dimethylsulfoxide (DMSO) and the absorbance was recorded at 595 nm by spectrophotometer. A linear correlation was observed between the absorbance of SBB and the number of platelets. By employing the SBB method, the influence of heparin on platelets-ECs interactions was observed. Heparin (3–100 units/mL) obviously reduced platelets adhering to ECs in a concentration-dependent manner. [ABSTRACT FROM AUTHOR]

Triacylglycerol is accumulated by Streptomyces spp. when grown in submerged culture. Ultrastructural studies using transmission electron microscopy (TEM), staining and freeze-fracture/freeze-etch procedures, and light microscopy confirmed the accumulation of neutral lipid by S. lividans and S. coelicolor during the stationary phase and its storage within membrane-bound globular structures within the cytoplasm. There structures were of various sizes and occupied up to approximately 80% of the total cell volume at that time. There was no evidence of such material within cells examined during the early exponential phase of growth. The globules visualised by TEM were electron-transparent since they comprised lipids containing saturated fatty acids that did not react with osmium tetroxide. The globules appeared to be bounded by a single membrane. [ABSTRACT FROM AUTHOR]

Cytochemical analysis of leukemic blasts from 46 patients with acute myeloblastic M2 leukemia (according to the FAB classification) was performed before and after cytostatic therapy, and compared with findings obtained in 20 age- and sex-matched control subjects. Cytochemical findings for myeloperoxidase (MPO), Sudan black B, acid phosphatase and alpha-naphthyl-acetate esterase (ANAE) were related to the achievement of the first complete remission (CR), i.e. data were compared after the patients had been divided into CR and non-CR groups. The analysis clearly showed that a high proportion of myeloperoxidase- and, to a lesser extent, Sudan black B-positive blasts before treatment may have constituted a significantly unfavourable prognostic factor. [ABSTRACT FROM AUTHOR]