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F. Mollaamin*, Sh. Momeni, M. Movahedi and M. Monajjemi
Abstract: Carbon nanotubes (CNTs) are very common in medical research and are being highly studied in the fields of biosensing methods for disease treatment and efficient drug delivery and health monitoring. The transportation of open-end Single wall carbon nanotube (SWCNT) through the cell membrane widely investigated because of many advantages. In our recent study, extensive quantum mechanical (QM) calculation of electronic structure of open-end of SWCNT and transportation of single wall carbon nanotube through the cell membrane have been administered in vacuum media using GAUSSIAN 98 software. Our results manifested that the interaction of open-end of SWCNT has minimum value of energy interaction and then most structural stability in vacuum. We assayed effects of vacuum on transportation of SWCNT through the cell membrane with using B1LYP and Hartree Fock (HF) methods at STO-3G, 3-21G, 6-31G levels of theory. Also, we demonstrated the total atomic charges of dense region calculated STO-3G, 3-21G and 6-31G basis sets in vacuum with HF method. The calculated values showed negative charge at this site. The O and S atoms at interaction site produced negative charge because they have high electron affinity.[...] Read More.
Keywords: Single wall carbon nanotube (SWCNT), quantum mechanical (QM), STO-3G, 3-21G and 6-31G basis.
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Salari Hassan*, Afzali Daryoush and Oliaie Mohammad Sadegh
Abstract: Bioremediation is a simple and effective technology for metal extraction from low-grade contaminated soils and mineral concentrates. Metal remove from sulfide minerals is based on the activity of mesophilic and chemolithotrophic bacteria, mainly ACIDITHIOBACILLUS FERROOXIDANS which convert insoluble metal sulfides into soluble metal sulfates. In this study bioremediation experiments carried out in 1 L Erlenmeyer flasks containing 300 ml basal medium of A. FERROOXIDANS and 5% (w/v) PbS with 45 and 75 meshes and also this condition repeated for ACIDITHIOBACILLUS THIOOXIDANS. The results showed that A. FERROOXIDANS had grown on the galena and obtained energy from it. Also, the galena was oxidized to form lead sulfate. The most important species for oxidizing galena concentrate showed A. FERROOXIDANS, because these species were more effective than A. THIOOXIDANS in our bioremediation experiments. Anglesite (PbSO4) was the important product of the galena bacterial oxidation. In these experiments the highest quantity of dissolute lead was 34% approximately in A. FERROOXIDANS cultures. The low solubility of lead sulphate indicated that this process is not commercially feasible for the recovery of lead on mines. In view of these results, bioremediation appears to have some potential for remediation of Pb contaminated soils.[...] Read More.
Keywords: Galena, acidithiobacillus ferrooxidans, acidithiobacillus thiooxidans, Ganat Marvan.
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Rose Koffi-Nevry*, Ama Lethicia Manizan, Kablan Tano, Yao Clément Yué Bi, Mathias K. Oulé and Marina Koussémon
Abstract: The antifungal activity of the Polyhexamethylene-guanidine hydrochloride (PHMGH)-based disinfectant against fungi isolated from papaya fruit was evaluated. The aim of this work was to show that the PHMGH can be used as a disinfectant for papaya preservation. Thirty one strains of fungi were isolated as Mucor sp., Botrytis sp., Penicillium sp., Geotrichum sp., Aspergillus sp. and Colletotrichum sp. Mucor sp. was the most isolated with a frequency of 52.77% followed by Botrytis (47.22%), Aspergillus and Penicillium (8.33%), Colletotrichum (5.56%) then, Geotrichum (2.78%). The antifungal activity of the PHMGH was tested through the determination of the minimal inhibitory concentrations (MICs) and the minimal fungicidal concentrations (MFCs). All the strains tested were sensitive to the disinfectant. However, the activity of PHMGH varies according to the strain tested. The values of the MIC and the MFC were between[...] Read More.
Keywords: Antifungal activity, minimum inhibitory concentrations (MICs), minimum fungicidal concentrations (MFCs), papaya preservation, polyhexamethylene-guanidine hydrochloride.
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N. Sri Kumaran, S. Bragadeeswaran* and S. Thangaraj
Abstract: The aim of this study was to screen the presence of antimicrobial activities in the marine mollusc Thais tissoti and Babylonia spirata. In this study, the human bacterial pathogen Klebsiella pneumonia (10.02 ± 0.11 mm) and fungal pathogen Aspergillus niger (12.09 ± 0.06 mm) showed most sensitive to ethyl acetate extracts of T. tissoti. In B. spirata extracts, bacterial pathogen Proteus mirabilis (7.02 ± 0.04 mm) and fungal pathogen Candida albicans (8.13 ± 0.15* mm) exhibit high zone of inhibition against n-butanol extracts. Among the fish bacterial pathogens assayed, Aeromonas hydrophila (9.22 ± 0.03* mm) and fungal pathogen Ichthyophonus sp. (5.21 ± 0.11 mm) showed more sensitivity to n- butanol extract of T. tissoti. In B. spirata extracts, bacterial pathogen A. hydrophila (11.2 ± 0.6* mm) and fungal pathogens A. niger (15.12 ± 0.23* mm) showed most sensitive to n-butanol extracts. From biofilm bacteria, Micrococcus luteus (7.02 ± 0.11* mm), Micrococcus sp. (7.25 ± 0.03* mm) showed high sensitivity to n-butanol extracts of molluscs T. tissoti and B. spirata. These results signify that the marine mollusc extracts express remarkable antimicrobial activity against isolated microbes. The result strongly suggests that the molluscs extracts can be used as antimicrobial agents and further studies for purification and structural elucidation of antimicrobial drugs.[...] Read More.
Keywords: Antibacterial, antifungal, human pathogen, fish pathogen, biofilm, marine mollusks.
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A. E. Ajiboye*, O. M. Kolawole, T. O. Oladosu, M. R. Adedayo and J. K. Akintunde
Abstract: Dried meat (Tinko) samples obtained from the Oja-Oba market in Ilorin metropolis during the rainy season were investigated for their microbial flora and the sensitivity of the bacterial isolates to different chemotherapeutic antibiotics under two different storage conditions (Cupboard and Refrigerator) for a period of five weeks revealed that the moisture content of dried meat samples stored in the cupboard increased from 35 to 65%, while those in the refrigerator had an initial increase from 50 to 55% for the first two weeks of storage and became constant through the period of storage. Bacteria and Fungi isolated include Staphylococcus aureus, Micrococcus luteus, Neisseria sp., Acinetobacter sp., Aspergillus niger, Aspergillus flavus, Penicillium sp. and Rhizopus sp. Bacterial isolates showed resistance to selected antibiotics (erythromycin, tetracycline, chloramphenicol, gentamycin, streptomycin, ofloxacin, nitrofurantoin, ciprofloxacin, azithromycin and clindamycin) except for Neisseria sp. which was sensitive to the antibiotics. The total bacterial count increased in the dried meat stored in the cupboard (2.5 × 107 to 3.3 × 107 cfu/ml) while it decreased in the meat samples stored in the refrigerator (2.0 × 107 to 1.4 × 107 cfu/ml).[...] Read More.
Keywords: Antibiotics, dried meat, bacteria, fungi, storage.
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Full Length Research Paper
Abstract: GB virus C (GBV-C)/hepatitis G virus (HGV) by infecting and encourage proliferative process of the mononuclear cells, may implicate in lymphomagenesis including non-Hodgkin’s lymphoma (NHL). Therefore, in this study the prevalence of GBV-C/HGV and HBV infections were evaluated in patients with NHL and controls. In a cross sectional study, blood samples were collected from 70 patients with NHL and 100 healthy controls. The infective markers of GBV-C/HGV and HBV viruses were evaluated in both studied groups by enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR) protocols, respectively. Anti-E2-Ab was detected in 1.4 of 70(1%) of NHL patients who has not the history of HBV infections. HGV-RNA was diagnosed in 2 of 70 (2.9%) of NHL patients and one of them was also shown the history of HBV infection. HGV-RNA was diagnosed in 1of 100 (1%) of controls but none of them was shown seroconversion to GBV-C/ HGV. HBV-DNA was found in 8 of 70 (11.6%) of NHL patients and 2 of 100 (2%) of controls. Significant differences were found in the prevalence of: HBV-DNA (P=0.013), HBsAb (P=0.001), and HBc-IgG-Ab (P=0.002) between NHL and controls. Determination of active and persistent infections of GBV-C/ HGV with or without HBV infection in NHL patients compared with control population proposed an association between viral hepatitis infections and NHL.[...] Read More.
Keywords: Non-Hodgkin’s lymphoma (NHL), GB virus C (GBV-C), hepatitis G virus (HGV).
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Mulissa Jida,* and Fassil Assefa
Abstract: Lentil (Lens culnaris Medik.) is an invaluable source of protein for the vast majority of Ethiopian people. It also maintains soil fertility through symbiotic nitrogen-fixation in association with Rhizobium leguminosarum bv. viciae. The aim of this study was selecting symbiotically efficient native lentil nodulating rhizobia endowed with different plant growth-promoting (PGP) characteristics. Hence, 30 lentil nodulating rhizobial isolates were isolated from soils collected from different farmer fields found in Central and Northern parts of the country. All isolates were characterized based on morphological, physiological, symbiotic and PGP characteristics. The result of this study showed that these isolates have exhibited interesting features such as wide range of carbon-sources and nitrogen sources utilization, tolerance to acidic and alkaline pH, metal toxicity and antibiotics. Symbiotic characterization indicated that all tested isolates have showed great diversity in their capacity to nodulate their host plant and produce shoot dry matter yield under glasshouse conditions. In addition, they showed PGP characteristics such as IAA production and inorganic phosphate solubilization. Out of all tested isolates 36.7% of them were IAA producer while only 16.7% were insoluble inorganic phosphate solubilizer. In general, from the present study, it can be concluded that Ethiopian soils harbor highly efficient nitrogen-fixing lentil nodulating rhizobia which are diverse in their morphological, physiological and symbiotic characteristics.[...] Read More.
Keywords: Lentil, Rhizobium, Ethiopia, IAA production, phosphate solubilization.
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S. Bragadeeswaran*, R. Jeevapriya, K. Prabhu, S. Sophia Rani, S. Priyadharsini and T. Balasubramanian
Abstract: The aim of the study was to isolate the exopolysaccharides (EPS) from the active biofilm bacterium Bacillus cereus GU 812900 which was isolated from the stainless steel test panel and deployed in the Vellar estuary for a period of about four weeks. The deployed stainless steel test panels when analyzed revealed a direct relationship between the rate of corrosion and the concentration of EPS that is, the rate of corrosion increased with an increase in the concentration of EPS and the period of immersion. Growth and EPS production by B. cereus strain GU812900 was studied in a basalt salt solution (BSS) containing (g/1); NaCl, 30.0; KCl 0.75; MgSO4.7H2O, 7.0; NH4Cl, 1.0; K2HPO4, 0.7; KH2PO4. 0.3; glucose, 10.0 and 1 ml of trace metal solution. The rate of EPS production in batch cultures was highest during the late log phase of the growth then stationary phase. The EPS was recovered from the culture supernatant by using ethanol precipitation – dialysis procedure. Chemical composition of EPS revealed that it is primarily composed of natural sugars, proteins, phosphates and sulphates. The EPS production was influenced by carbon, nitrogen and phosphate concentrations in the growth medium. EPS produced by B. cereus GU812900 is a heteropolysaccharide which influence the corrosion. The FTIR analysis revealed the functional groups of the EPS. The results of the study was expressed the relationship between biocorrosion and biofilm formation of the stainless steel test panels. Key  words:  Biofilm,  exopolysaccharides  (EPS),  sequencing,  secondary  metabolite,  characterization, FTIR analysis.[...] Read More.
Keywords:
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Full Length Research Paper
Abstract: In our previous studies, Rat-1 cells treated with Vibrio parahaemolyticus thermostable direct hemolysin (TDH) developed morphological changes including shrinkage and rounding of the cells. Such alterations suggest that TDH stimulates reorganization of the cellular cytoskeleton. In the current study, the effects of TDH on actin cytoskeleton, chromatin, and caspase-3 were evaluated. Rat-1 cells treated with TDH 5 µg/ml showed redistribution of actin with loss of stress fibers, a floccular staining pattern, cellular membrane blebbing, and cell rounding as assessed by fluorescent actin-staining. This actin redistribution was time dependent. Actin was rapidly disappeared within 10 min after TDH exposure, and the maximal effect was detected by 30 min. TDH-treated cells also showed chromatin condensation which is time dependent. The changes were also detected by as early as 10 min, with the maximal effect by 20 min. Moreover, caspase-3 was activated in TDH-treated Rat-1 cells by time-dependent manner. Pretreatment with a caspase inhibitor (ZVAD-FMK) partially reduced the activation of caspase-3 in the TDH-treated cells. All of the changes found in this study appear to be linked, and the findings, especially activation of caspase-3 in TDH-treated Rat-1 cells, provide a new insight into TDH-mediated cytotoxicity.[...] Read More.
Keywords: Thermostable direct hemolysin (TDH), Vibrio parahaemolyticus, Rat-1 cells, actin disruption, caspase-3 activation, chromatin condensation.
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Majid Sadeghi*, Mohammad Hasan Bozorgemehrifard, Hadi keyvanfar, Hassan Momtaz, Abdolhamid Shooshtari and Saied Charkhkar
Abstract: Avian infectious laryngotracheitis (ILT) is a severe clinical respiratory disease of chickens and causes the clinical symptoms of difficulty in breathing and bloody coughing and as if involves laying hens affect the egg production. Two different regions of the infected cell protein 4 (ICP4) gene of infectious laryngotrucheitis virus (ILTV) were amplified and sequenced for characterization of field isolates and tissue culture-origin (TCO) and chicken embryo-origin (CEO) vaccine strains. Phylogenetic analysis of the two regions showed no differences in nucleotide and amino acid sequences between Iranian field isolates with high morbidity and nearly 30% mortality and CEO attenuated vaccines. These findings suggest that modified-Live (ML) ILT vaccine viruses may increase in virulence after bird-to-bird passages.[...] Read More.
Keywords: Avian infectious laryngotracheitis, infected cell protein 4, phylogenetic analysis.
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