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1.
Phage therapy is considered an alternative modality in the treatment of different bacterial diseases. However, their therapeutic and preventive roles against infections caused by Salmonella Kentucky and Escherichia coli O119 were of little attention. In this study, two phages were isolated, characterized and assessed for their potential therapeutic and preventive roles against S. Kentucky and E. coli O119 infections in broilers. Commercial 1-day-old arboacres broiler chicks were assigned to seven groups: Group Ӏ was as a negative control, groups (П and Ш) were assigned as positive controls by the challenge of S. Kentucky and E. coli O119, respectively. The remaining four groups (IV, V, VI and VII) were administrated with five repeated phage doses to determine the effect of multiple doses. Phages were administrated in groups (IV and VI) after challenging with S. Kentucky and E. coli O119, respectively to assess their therapeutic role; moreover, their preventive role was evaluated through administration in groups (V and VII) before challenging with S. Kentucky and E. coli O119, respectively. Sampling was done from different organs at three time points and revealed that phage-treated groups had lower colony forming units of S. Kentucky and E. coli. Our results suggest that bacteriophages are efficient in the treatment and prevention of salmonellosis and colibacillosis in broiler farms.  相似文献   
2.
In an attempt to obtain biological control agents for controlling bacterial spot of cucumber, over 250 bacterial strains were isolated from agricultural soil samples, collected from different localities in Giza Governorate (Egypt) and screened for in vitro antibiosis towards Xanthomonas campestris. Only 2 strains showed antagonistic activity. They and their culture filtrates restricted the growth of a number of G- and G(+)-indicator bacteria. On Chrome Azurol S agar, both strains exhibited a marked siderophore production. Biolog plates identified these strains as Rahnella aquatilis. Their characteristics were studied and compared with literature data on R. aquatilis. This antagonistic bacterium has not been previously isolated in Egypt.  相似文献   
3.
The prevalence of resistance to high levels of gentamicin among 182 isolates of Enterococcus faecalis from 2 Iranian hospitals was 42%. Gentamicin resistance was associated with conjugative plasmids (>70 kb) in most strains. Fingerprinting using EcoRI and HindIII showed genetic variation among these plasmids and gave evidence of nosocomial outbreaks and persistence of infection in different wards of the study hospitals, as well as transfer of plasmids between genetically diverse isolates. Using EcoRI, hospital-based specific plasmid fingerprints were detected for the isolates that had previously proved to be unrelated by multilocus enzyme electrophoresis, suggesting the persistence of related plasmids at each hospital, though minor changes in these related plasmids could be detected with HindIII.  相似文献   
4.
The distribution of atrial natriuretic peptide (ANP) in blood plasma and cardiac muscle and its effects on ventricular myocyte contraction and intracellular free calcium concentration [Ca2+]i in the streptozotocin (STZ)-induced diabetic rat have been investigated. Blood plasma concentration and heart atrial and ventricular contents of ANP were significantly increased in STZ-treated rats compared to age-matched controls. STZ treatment increased the number of ventricular myocytes immunolabeled with antibodies against ANP. In control myocytes the percentage of cells that labeled positively and negatively were 17% versus 83%, respectively. However, in myocytes from STZ-treated rat the percentages were 52% versus 53%. Time to peak (TPK) shortening was significantly and characteristically prolonged in myocytes from STZ-treated rats (360+/-5 ms) compared to controls (305+/-5 ms). Amplitude of the Ca2+ transient was significantly increased in myocytes from STZ-treated rats compared to controls (0.39+/-0.02 versus 0.29+/-0.02 fura-2 RU in controls) and treatment with ANP reduced the amplitude of the Ca2+ transient to control levels. ANP may have a protective role in STZ-induced diabetic rat heart.  相似文献   
5.
The Protein Journal - As a safe substitute for hydroquinone, β-arbutin, a natural plant substance, and its synthetic counterpart, α-arbutin, are used in depigmentation formulations....  相似文献   
6.
International Journal of Peptide Research and Therapeutics - β-secretase 1 (BACE1) plays a pivotal role in the pathology of Alzheimer?s disease via accumulation beta amyloid in the...  相似文献   
7.
It has been suggested that mood disorders and depressive status may be accompanied by lowered zinc status in the body, and adequate consumption of zinc increases a general perceived well-being. The main objective of this study was to assess the correlation between serum zinc concentrations and dietary zinc intakes with depression scores in university female students. In the first phase, Beck's depression questionnaire was applied in a random sampling of 308 selected 20–25-year-old female students (one third of total students in Ahvaz Jondi-Shapour University of Medical Sciences Golestan dormitories) to assess the major depressive disorder (MDD) scales. Then, in the second phase, 23 students who identified as having moderate and severe depression were selected as the case group, and 23 healthy age matched were chosen as the controls. Each of them completed a 12-item semiquantitative food frequency questionnaire containing the main food sources of zinc in the usual dietary patterns and also a 24-h food recall questionnaire to assure the daily zinc intakes. Daily zinc intakes were obtained by multiplying each portion size by its zinc content using food tables. A 5-ml blood sample was taken for further serum zinc status using flame atomic absorption spectrophotometry technique. Pearson's r was used to show the correlation between quantitative variables. Both daily zinc intake and serum zinc concentrations of MDD group were about two thirds of healthy index (p < 0.01). Depressed individuals used to eat lower servings of red meats and chicken as the main food sources of zinc in students' usual diets (p < 0.001). Consumption of other foods as the sources of zinc was not significantly different in two groups. A linear significant correlation between dietary zinc intakes and its serum levels was seen in samples (r = 0.62; p < 0.001) and MDD students (r = 0.55; p < 0.001). There was a linear inverse correlation between Beck questionnaire scores and serum zinc concentrations in all of the investigated students(r = -0.65; p < 0.001) and MDD girls (r = −0.71; p < 0.001). Beck questionnaire scores and diatary zinc intakes were also inversly correlated (r = −0.58; p < 0.001). However, no statistical correlation was seen between these two variables in MDD cases. In depressed female students, dietary zinc intake is correlated to its serum concentrations; however, the serum zinc levels are inversely correlated to depression scales. Consumption of the main dietary sources of zinc such as red meats and chicken should be encouraged in young depressed girls.  相似文献   
8.
A Short cut graphical procedure has been developed analogous to stepwise for the design of continuous flow sedimentation or thickening tanks.In this technique, several computer programs have been set up in order to reduce the data input, necessary for performing all intermediate calculations by computer. The data describing the settling of particles and movement of the particle-liquid interface as a function of time and operating conditions are the only data required. The method predicts the time required to attain the prescribed underflow concentration, the rate of hindered settling subsidence, the area required for clarification, the thickener area and dimensions. The proposed method has been applied to illustrate the effect of different chemical treatment doses on a typical industrial effluent from the manufacture of starch and byproducts from American yellow corn.List of Symbols A1 cm First falling zone line intercept - A2 cm Settling zone curve intercept - A3 cm Compression zone line intercept - A4 cm Angle bisector intercept - A5 cm Tangent interception at the compression point - ACL m2 Minimum clarification area - ALPHA() Angle between line 1 and line 2, radians - ATH m2 Minimum thickening area - ATH1 m2 Area of each individual tank - B1 cm · min–1 First falling zone line slope - B2 Settling zone curve power - B3 cm · min–1 Compression zone line slope - B4 cm · min–1 Angle bisector slope - B5 cm · min–1 Tangent slope at the compression point - BT m Approximate width of the tank - BT1 m Actual width of the tank - CC Conversion criteria - CO mg/dm3 Initial solid concentration - CU mg/dm3 Underflow solid concentration - D m Basin depth - DIAM m Diameter of circular tank - DMIN m Minimum allowable liquid depth - DT h Minimum allowable detention time - DT1 h Calculated detention time - HT cm Subsiding particle-liquid interface height - HT1 min Subsiding particle-liquid interface coordinate for line 1 and line 2 intersection - HTR cm Subsiding particle-liquid interface coordinate for compression point - L m Approximate length of the tank - L1 m Actual length of the tank - LMAX m Maximum allowable tank length - LMIN m Minimum allowable tank length - NI Number of iterations - NO Number of tanks - PI Const. - Q m3/h Wastewater flowrate - SL m3/(m2 · d) Surface loading - T1 Tan() - T3 Tan (/2) - TM min Time of measuring subsiding particle-liquid interface - TM1 min Time coordinate for line 1 and line 2 intersection - TML min Lower limit of the root - TMR min Time coordinate for compression point - TMU min Upper limit of the root - TU min Time required to attain underflow concentration - ZO cm Initial height of sludge - ZU cm Settled height of sludge interface - FI m Inert depth (typically taken as 1 m)  相似文献   
9.
The enzymatic synthesis of phenolic lipids (PLs) by transesterification of flaxseed oil with 3,4-dihydroxyphenyl acetic acid (DHPA) was investigated in solvent-free medium (SFM), using Novozym 435 from Candida antarctica as the biocatalyst. The effects of selected reaction parameters, water activity (aw), enzyme concentration and agitation speed, were studied and optimized. Increasing the aw of the reaction mixture from 0.18 to 0.38 resulted in a significant increase in the bioconversion yield from 62 to 77%. APCI–MS analysis confirmed the formation of six 3,4-dihydroxyphenyl acetoylated lipids, which were monolinolenyl, dioleyl, dilinolenyl, linoleyl linolenyl, oleyl linolenyl and oleyl linoleyl dihydroxyphenyl acetates. The highest enzymatic activity (178 nmol of PLs/g solid enzyme/min) was obtained using 40 mg of solid enzyme (400 PLU)/mL at agitation speed 150 rpm. Using the optimized conditions, the phenolic lipids showed a high relative proportion of linolenic acid (C18:3 n?3) that increased from 57% in the flaxseed oil to 75 and 64% in the produced phenolic mono- and diacylglycerols, respectively. In addition, the synthesized phenolic lipids demonstrated a 7.2-fold lower radical scavenging activity than that of DHPA but half that of α-tocopherol.  相似文献   
10.
Grafting of monomer onto polymer backbone is one of the effective and accessible methods for the chemical modification of polysaccharides. Grafting of acrylamide (AAm) onto polysaccharides blend (PsB) composed of starch, chitosan and alginate has been carried out using potassium persulfate (KPS) as an initiator. The kinetics of the grafting polymerization also has been studied. The grafting parameters have been evaluated by changing the initial concentrations of AAm from 8 to 16 g, PsB from 6 to 14 g and KPS from 0.2 to 1 g. Evidence of grafting has been obtained from FTIR, XRD and TGA. The kinetics of the grafting polymerization also has been studied. The grafting rate equation of the produced hydrogel (PsB-g-AAm) hydrogel has been expressed by: Rg = k[AAm] [PsB]0.5 [KPS]0.5. The grafting rate is a first order dependence to [AAm] initial concentration and square root to [PsB] and [KPS] initial concentrations in the used concentrations range.  相似文献   
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