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81.
Russian Journal of Bioorganic Chemistry - In the present research work, a new series of N-(substituted-phenyl)-3-(4-phenyl-1-piperazinyl)propanamides were synthesized. The synthesis was initiated...  相似文献   
82.
Liver disorders may occur as a result of exposure to chemical compounds capable of inducing the oxidative stress and hepatic injuries. The aim of present study was to investigate the effects of flower extracts of B. Variegata for the treatment of liver injury induced by the CCl4. About 1 ml/kg body weight (b.w) of CCl4 was induced to experimental mice by intraperitoneal way for 14 days. The methanol and chloroform extracts (100, 200 and 300 mg/kg b.w) were administered to experimental animals for 14 days along with standard drug Silymarine (100 mg/kg b.w). The extracts alone showed no evidence of hepatic toxicity but animals exposed to CCl4 without the treatment with B. Variegata presented variations in levels of liver enzymes, antioxidant enzymes, proteins and blood cells as well as injuries in liver cells were also observed during histopathological study. However, after the treatments especially with 300 mg/kg b.w of methanol flower extracts levels of liver markers (ALT, AST and ALP), antioxidant enzymes and blood cells decreases and turned towards normal levels. Whereas level of total proteins and bilirubin was improved and damaged liver cells were repaired. The curative activity of flower extracts can be correlated to the higher potential of antioxidants and occurrence of Quercetin and some other organic compounds those were investigated from flower extracts of B. Variegata during HPLC and GC-MS analysis. The finding of this study supports the use of B. Variegata flower formulation in folk medicines.  相似文献   
83.
The cytotoxicity in freshwater fishes due to different industrial dyes in industrial effluents is a major worldwide issue. Hematoxylin dye has a wide range of uses in textile industries and laboratories. This study was aimed to evaluate the toxic effects of hematoxylin's sublethal effect in vitro in Cirrhinus mrigala. The fish was exposed to different grading concentrations of dye in the aquarium. Fish were sacrificed and dissected to remove the kidney after exposure to hematoxylin dye for specific time intervals. Nephrotoxicity and cytotoxicity induced by this dye were detected through histopathology by using the paraffin wax method. Immediate mortality of fish was noticed against the exposure to 0.08 g/L (LC50) concentration of dye, but at 0.008 mg/L and 0.018 mg/L, it showed tremendous tissue damage in the kidneys, significant reduction in fish growth. This dye induced many alterations in the kidney such as tubular degeneration, vacuolation, shrinkage of a glomerulus, reduced lumen, congestion in the kidney, glomerulonephritis, absence of Bowmen space, necrosis of the hematopoietic interstitial tissues, clogging of tubules, necrosis in the glomerulus and increased space between glomerulus and bowmen's capsule. Although this dye has a wide range of biological and industrial applications, a minute amount of hematoxylin released in effluents is quite toxic to aquatic fauna.  相似文献   
84.
Background & objectivesRosuvastatin calcium (RC) is a potent and competitive synthetic inhibitor of HMG-CoA reductase used for the treatment of dyslipidemia. Guggulipid obtained from Commiphora mukul is used in the treatment of a wide variety of diseases such as atherosclerosis, hypercholesterolemia, rheumatism, and obesity. The present study evaluates the pharmacokinetic and pharmacodynamic interactions between RC and the standardized guggulipid extract in rats.Materials and methodsThe guggulipid extract was standardized for the presence of guggulsterones. The pharmacokinetic interaction was determined after a single dose administration of RC alone or in combination with the guggulipid extract or after multiple-dose administration of RC alone or RC along with the guggulipid extract for 14 days. To determine the pharmacodynamic interaction, RC and guggulipid extract were administered to hyperlipidemic rats for 14 days. The level of significance was determined using unpaired student’s t-test, one way ANOVA, the post-ANOVA Tukey test.ResultsStandardization of guggulipid extract showed it contains 7.5%w/w of guggulsterones. Guggulipid extract increased the bioavailability of RC in both single-dose and multiple-dose studies. Guggulipid extract reduced the rate of absorption (Ka) of RC but showed an increase in maximum serum concentration (Cmax). An in-vitro study using isolated rat intestine revealed that guggulipid extract decreased the rate of absorption of RC in the intestinal lumen. The hypolipidemic activity of RC was augmented by the guggulipid extract in hyperlipidemic rats.Interpretation & conclusionTherefore it is concluded that guggulipid extract increases the bioavailability of RC by delaying its Ka and augments its hypolipidemic action. However, it is recommended that a combination of RC with guggulipid extract should be used only after an adverse effect(s) of this combination are determined.  相似文献   
85.
Honey bee is vital for pollination and ecological services, boosting crops productivity in terms of quality and quantity and production of colony products: wax, royal jelly, bee venom, honey, pollen and propolis. Honey bees are most important plant pollinators and almost one third of diet depends on bee’s pollination, worth billions of dollars. Hence the role that honey bees have in environment and their economic importance in food production, their health is of dominant significance. Honey bees can be infected by various pathogens like: viruses, bacteria, fungi, or infested by parasitic mites. At least more than 20 viruses have been identified to infect honey bees worldwide, generally from Dicistroviridae as well as Iflaviridae families, like ABPV (Acute Bee Paralysis Virus), BQCV (Black Queen Cell Virus), KBV (Kashmir Bee Virus), SBV (Sacbrood Virus), CBPV (Chronic bee paralysis virus), SBPV (Slow Bee Paralysis Virus) along with IAPV (Israeli acute paralysis virus), and DWV (Deformed Wing Virus) are prominent and cause infections harmful for honey bee colonies health. This issue about honey bee viruses demonstrates remarkably how diverse this field is, and considerable work has to be done to get a comprehensive interpretation of the bee virology.  相似文献   
86.
Due to their inexpensive and eco-friendly nature, and existence of manganese in various oxidation states and their natural abundance have attained significant attention for the formation of Mn3O4 nanoparticles (Mn3O4 NPs). Herein, we report the preparation of Mn3O4 nanoparticles using manganese nitrate as a precursor material by utilization of a precipitation technique. The as-prepared Mn3O4 nanoparticles (Mn3O4 NPs) were characterized by using X-ray powder diffraction (XRD), UV–Visible spectroscopy (UV–Vis), High-Resolution Transmission electron microscopy (HRTEM), Field emission scanning electron microscopy (FESEM), Thermal gravimetric analysis (TGA) and Fourier-transform infrared spectroscopy (FT-IR). The antimicrobial properties of the as-synthesized Mn3O4 nanoparticles were investigated against numerous bacterial and fungal strains including S. aureus, E. coli, B. subtilis, P. aeruginosa, A. flavus and C. albicans. The Mn3O4 NPs inhibited the growth of S. aureus with a minimum inhibitory concentration (MIC) of 40 μg/ml and C. albicans with a MIC of 15 μg/ml. Furthermore, the Mn3O4 NPs anti-cancer activity was examined using MTT essay against A549 lung and MCF-7 breast cancer cell lines. The Mn3O4 NPs revealed significant activity against the examined cancer cell lines A549 and MCF-7. The IC50 values of Mn3O4 NPs with A549 cell line was found at concentration of 98 µg/mL and MCF-7 cell line was found at concentration of 25 µg/mL.  相似文献   
87.
Cell–cell and cell–matrix adhesions are fundamental to numerous physiological processes, including angiogenesis, tumourigenesis, metastatic spreading and wound healing. We use cellular potts model to computationally predict the organisation of cells within a 3D matrix. The energy potentials regulating cell–cell (JCC) and cell–matrix (JMC) adhesive interactions are systematically varied to represent different, biologically relevant adhesive conditions. Chemotactically induced cell migration is also addressed. Starting from a cluster of cells, variations in relative cell adhesion alone lead to different cellular patterns such as spreading of metastatic tumours and angiogenesis. The combination of low cell–cell adhesion (high JCC) and high heterotypic adhesion (low JMC) favours the fragmentation of the original cluster into multiple, smaller cell clusters (metastasis). Conversely, cellular systems exhibiting high-homotypic affinity (low JCC) preserve their original configuration, avoiding fragmentation (organogenesis). For intermediate values of JCC and JMC (i.e. JCC/JMC ~ 1), tubular and corrugated structures form. Fully developed vascular trees are assembled only in systems in which contact-inhibited chemotaxis is activated upon cell contact. Also, the rate of secretion, diffusion and sequestration of chemotactic factors, cell deformability and motility do not significantly affect these trends. Further developments of this computational model will predict the efficacy of therapeutic interventions to modulate the diseased microenvironment by directly altering cell cohesion.  相似文献   
88.
In the vermicomposting of paper mill sludge, the activity of earthworms is very dependent on dietetic polysaccharides including cellulose as energy sources. Most of these polymers are degraded by the host microbiota and considered potentially important source for cellulolytic enzymes. In the present study, a metagenomic library was constructed from vermicompost (VC) prepared with paper mill sludge and dairy sludge (fresh sludge, FS) and functionally screened for cellulolytic activities. Eighteen cellulase expressing clones were isolated from about 89,000 fosmid clones libraries. A short fragment library was constructed from the most active positive clone (cMGL504) and one open reading frame (ORF) of 1,092 bp encoding an endo-β-1,4-glucanase was indentified which showed 88% similarity with Cellvibrio mixtus cellulase A gene. The endo-β-1,4-glucanase cmgl504 gene was overexpressed in Escherichia coli. The purified recombinant cmgl504 cellulase displayed activities at a broad range of temperature (25–55°C) and pH (5.5–8.5). The enzyme degraded carboxymethyl cellulose (CMC) with 15.4 U, while having low activity against avicel. No detectable activity was found for xylan and laminarin. The enzyme activity was stimulated by potassium chloride. The deduced protein and three-dimensional structure of metagenome-derived cellulase cmgl504 possessed all features, including general architecture, signature motifs, and N-terminal signal peptide, followed by the catalytic domain of cellulase belonging to glycosyl hydrolase family 5 (GHF5). The cellulases cloned in this work may play important roles in the degradation of celluloses in vermicomposting process and could be exploited for industrial application in future.  相似文献   
89.
Sets of tetrasubstituted thiophene esters 4a-4g, 5a-5f and 6a-6e were synthesized by reaction of 1-(α-Carbomethoxy-β-aminothiocrotonoyl)-aryl/aroyl amines (3) with 3-(bromoacetyl)coumarin, 1,4-dibromodiacetyl and chloroacetone respectively. The compound 3 were synthesized by nucleophilic addition of aryl/aroylisothiocyanate and enamine (2). The synthesized targeted compounds (4a-4g, 5a-5f and 6a-6e) were evaluated for their in vivo anti-inflammatory activity in carrageenin-induced rat hind paw oedema model at three graded doses employed at 10, 20 and 40 mg/kg body weight using mefanamic acid, ibuprofen and in vivo analgesic activity in acetic acid induced writhing response model at 10 mg/kg dose using ibuprofen as standard drug. The compounds 4a-4f, 5c, 5f, 6c and 6e were evaluated for their in vitro antioxidant nitric oxide radical scavenging assay at the concentrations of 5, 10, 15, 20, 25, 30 and 35 μg/mL using ascorbic acid as standard drug. Among all the targeted compounds 4c showed maximum anti-inflammatory activity of 71% protection at 10 mg/kg and 77% protection at 20 mg/kg to inflamed paw and analgesic activity of 56% inhibition and also maximum in vitro nitric oxide radical scavenging activity having IC50 value 31.59 μg/mL.  相似文献   
90.
In this study, a sensitive and simple flow‐injection chemiluminescence (CL) method was developed for the quantitative analysis of haemoglobin. The method is based on the ability of haemoglobin to enhance the CL signal generated by a H2O2–K4Fe(CN)6–fluorescein alkaline system enhanced by CdTe quantum dots. Under the optimized conditions, haemoglobin can be detected in concentration range 7.35 × 10–9–2.5 × 10–6 mol/L, with a detection limit (3σ) of 1.8 × 10–9 mol/L and a relative standard deviation (RSD; for 5 × 10–7 mol/L haemoglobin) of 2.06% (n = 11). The present CL method was successfully applied for the determination of haemoglobin in three kinds of blood samples taken from an infant, an adult man, an adult woman and two reference samples. Compared with previous reports, the CL method described in this work is simple and rapid, with high sensitivity. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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