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161.
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163.
This paper presents results on anaerobic degradation of the azo dye blue HFRL in a bench scale Upflow anaerobic sludge blanket
(UASB) reactor operated at ambient temperature. The results show that the addition of yeast extract (500 mg/L) increased color
removal (P < 0.05) from 62 to 93% despite the low chemical oxygen demand (COD) removal (~35%) which happened due to volatile fatty acids
(VFA) accumulation. There were no differences in color removal (~91%) when yeast extract (500 mg/L) was used in the presence
or absence of glucose, suggesting that yeast extract acted as source of redox mediator (riboflavin) and carbon. The specific
rate of dye removal increased along the operational phases and depended on the presence of yeast extract, suggesting progressive
biomass acclimatization. Analysis of bacterial diversity by Polymerase Chain Reaction-Denaturing Gradient Gel Electrophoresis
(PCR–DGGE) method showed there was biomass selection along the bioreactor operation and no evidence of azo dye degrading bacteria
predominance. This strengthens the hypothesis that color removal happens extracellularly by the reduction of azo bond by reduced
redox mediators, such as riboflavin, which is present in high amount in the yeast extract. 相似文献
164.
Mycoplasma bovis pneumonia in cattle has been epidemic in China since 2008. To investigate M. bovis pathogenesis, we completed genome sequencing of strain HB0801 isolated from a lesioned bovine lung from Hubei, China. The genomic plasticity was determined by comparing HB0801 with M. bovis strain ATCC? 25523?/PG45 from cow mastitis milk, Chinese strain Hubei-1 from lesioned lung tissue, and 16 other Mycoplasmas species. Compared to PG45, the genome size of HB0801 was reduced by 11.7 kb. Furthermore, a large chromosome inversion (580 kb) was confirmed in all Chinese isolates including HB0801, HB1007, a strain from cow mastitis milk, and Hubei-1. In addition, the variable surface lipoproteins (vsp) gene cluster existed in HB0801, but contained less than half of the genes, and had poor identity to that in PG45, but they had conserved structures. Further inter-strain comparisons revealed other mechanisms of gene acquisition and loss in HB0801 that primarily involved insertion sequence (IS) elements, integrative conjugative element, restriction and modification systems, and some lipoproteins and transmembrane proteins. Subsequently, PG45 and HB0801 virulence in cattle was compared. Results indicated that both strains were pathogenic to cattle. The scores of gross pathological assessment for the control group, and the PG45- and HB0801-infected groups were 3, 13 and 9, respectively. Meanwhile the scores of lung lesion for these three groups were 36, 70, and 69, respectively. In addition, immunohistochemistry detection demonstrated that both strains were similarly distributed in lungs and lymph nodes. Although PG45 showed slightly higher virulence in calves than HB0801, there was no statistical difference between the strains (P>0.05). Compared to Hubei-1, a total of 122 SNP loci were disclosed in HB0801. In conclusion, although genomic plasticity was thought to be an evolutionary advantage, it did not apparently affect virulence of M. bovis strains in cattle. 相似文献
165.
Gökbel H Okudan N Gül I Belviranli M Gergerlioğlu HS Başaral MK 《Journal of strength and conditioning research / National Strength & Conditioning Association》2012,26(6):1675-1679
The objective of the study was to determine the effects of repeated bouts of supramaximal exercise on plasma adiponectin, interleukin (IL)-6 and tumor necrosis factor (TNF)-α levels in sedentary men. Fourteen healthy, nonsmoking, and sedentary men aged between 18.4 and 21.4 years participated in the study. All the subjects performed 5 Wingate tests (WTs) with 75 g per kilogram body weight load with 2-minute intervals between the tests. Blood samples were collected at preexercise, immediately after, 15 and 60 minutes after the fifth WT. Serum and plasma samples were stored at -80°C until the time of analysis for myoglobin, adiponectin, IL-6, and TNF-α. Plasma adiponectin levels decreased, whereas IL-6 levels increased postexercise compared with that preexercise. The TNF-α levels were not changed with supramaximal exercise. In conclusion, repeated bouts of supramaximal exercise cause an inflammatory response in exercised muscle and increase in plasma IL-6 levels and decrease in adiponectin concentrations. 相似文献
166.
Muthuraman Pandurangan Dawoon Jeong Touseef Amna Hoa Van Ba Inho Hwang 《In vitro cellular & developmental biology. Animal》2012,48(9):577-582
The present study was carried out to understand the co-culture effect of C2C12 and 3T3-L1 preadipocyte cells on calpain, caspase, and heat shock protein (Hsp) systems. Calpains, caspases, and heat shock proteins play critical roles in the growth and development of mammalian cells. Cells were co-cultured using transwell inserts with a 0.4-??m porous membrane to separate C2C12 and 3T3-L1 preadipocyte cells. Each cell type was grown independently on the transwell plates. Following cell differentiation, inserts containing 3T3-L1 cells were transferred to C2C12 plates and inserts containing C2C12 transferred to 3T3-L1 plates. Following co-culture for 24 and 48?h, the cells in the lower well were harvested for analysis. Calpains include ??-calpain, m-calpain, and their specific inhibitor calpastatin. The expression pattern of ??-calpain did not change in the co-cultured C2C12 and 3T3-L1 cells, whereas m-capain mRNA expression significantly reduced in the 48-h co-cultured 3T3-L1 cells. Calpastatin mRNA expression significantly increased in the 48-h co-cultured C2C12 cells. Caspase-7 mRNA expression did not change in the 24- and 48-h co-cultured C2C12 and 3T3-L1 cells. Caspase-3 mRNA expression significantly reduced in the 24- and 48-h co-cultured 3T3-L1 cells; caspase-9 mRNA had a significant reduction only at 48?h, whereas caspase-9 mRNA expression significantly increased in the 48-h co-cultured C2C12 cells. Hsp27 and Hsp90 mRNA expressions are significantly reduced in the 24- and 48-h co-cultured C2C12 and 3T3-L1 cells, whereas Hsp70 mRNA expression significantly increased in the 48-h co-cultured 3T3-L1 cells. The co-culture reflects three-dimensional views of C2C12 and 3T3-L1 cell types as in vivo, which is quite distinct from the one-dimensional monocultured C2C12 and 3T3-L1 cells. 相似文献
167.
S100A6, a calcium-binding protein also known as calcyclin, was detected in human umbilical cord by immunoblotting. Immunohistochemical studies showed an intensive reaction for S100A6 in the walls of vessels and Wharton's jelly. In the latter, S100A6 was found not only in the myofibroblasts but also in the ECM (extracellular matrix) surrounding these cells. Affinity chromatography of S100A6 resin indicated that Wharton's jelly contains some proteins that could bind to S100A6. Thus these novel results show the presence of S100A6 in umbilical cord and suggest the involvement of this protein in intra- and extra-cellular signalling pathways in this tissue. 相似文献
168.
Prudhomme J Gunay F Rahola N Ouanaimi F Guernaoui S Boumezzough A Ba?uls AL Sereno D Alten B 《Journal of vector ecology》2012,37(1):137-147
The wing shape and size morphology of populations of the medically important phlebotomine sand fly, Phlebotomus papatasi, were examined in two endemic (south of the Atlas Mountains) and nonendemic (north of the Atlas Mountains) foci of cutaneous leishmaniasis by using geometric morphometrics in Morocco. Although it is present in all of Morocco, P. papatasi is the main vector of Leishmania major in only southern part of the Atlas Mountains. There are four major mountain ranges that serve as geographical barriers for species distribution in the study area and at least four gaps were recognized among these barriers. We found statistically significant differences in wing shape morphology between southern and northern populations. Analysis clearly recognized two main groups of populations on both sides of the mountains. The graphical depiction of Principal Component Analysis (PCA) and Canonical Variates Analysis (CVA) confirmed our morphometric study suggesting that the difference in wing morphology between the populations indicates that the population of P. papatasi shows phenotypic plasticity in the study area. According to centroid size analyses, which were used as measures of wing size differences among different sites, the north population of P. papatasi had relatively larger wings than the south population. 相似文献
169.
Rey-Cuille MA Seck A Njouom R Chartier L Sow HD Mamadou Ka AS Njankouo M Rousset D Giles-Vernick T Unal G Sire JM Garin B Simon F Vray M 《PloS one》2012,7(5):e38153
HBV vaccine was introduced into the Expanded Programme on Immunization (EPI) in Senegal and Cameroon in 2005. We conducted a cross-sectional study in both countries to assess the HBV immune protection among children. All consecutive children under 4 years old, hospitalized for any reason between May 2009 and May 2010, with an immunisation card and a complete HBV vaccination, were tested for anti-HBs and anti-HBc. A total of 242 anti-HBc-negative children (128 in Cameroon and 114 in Senegal) were considered in the analysis. The prevalence of children with anti-HBs ≥ 10 IU/L was higher in Cameroon with 92% (95% CI: 87%-97%) compared to Senegal with 58% (95% CI: 49%-67%), (p<0.001). The response to vaccination in Senegal was lower in 2006-2007 (43%) than in 2008-2009 (65%), (p = 0.028). Our results, although not based on a representative sample of Senegalese or Cameroonian child populations, reveal a significant problem in vaccine response in Senegal. This response problem extends well beyond hepatitis B: the same children who have not developed an immune response to the HBV vaccine are also at risk for diphtheria, tetanus, pertussis (DTwP) and Haemophilus influenzae type b (Hib). Field biological monitoring should be carried out regularly in resource-poor countries to check quality of the vaccine administered. 相似文献
170.
Diphtheria toxin (DT) and its N-terminal fragment A (FA) catalyse the transfer of the ADP-ribose moiety of nicotinamide adenine
dinucleotide (NAD) into a covalent linkage with eukaryotic elongation factor 2 (eEF2). DT-induced cytotoxicity is versatile,
and it includes DNA cleavage and the depolymerisation of actin filaments. The inhibition of the ADP-ribosyltransferase (ADPrT)
activity of FA did not affect the deoxyribonuclease activity of FA or its interaction with actin. The toxin entry rate into
cells (HUVEC) was determined by measuring the ADP-ribosyltransferase activity. DT uptake was nearly 80% after 30 min. The
efficiency was determined as Km = 2.2 nM; Vmax = 0.25 pmol.min−1. The nuclease activity was tested with hyperchromicity experiments, and it was concluded that G-actin has an inhibitory effect
on DT nuclease activity. In thepresence of DT and mutant of diphtheria toxin (CRM197), F-actin depolymerisation was determined
with gel filtration, WB and fluorescence techniques. In the presence of DT and CRM197, 60–65% F-actin depolymerisation was
observed. An in vitro FA-actin interaction and F-actin depolymerisation were reported in our previous paper. The present study thus confirms the
depolymerisation of actin cytoskeleton in vivo. 相似文献