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144.
Alper Bayrakdar Erkan SahinkayaMurat Gungor Sinan UyanikA. Dilek Atasoy 《Bioresource technology》2009,100(19):4354-4360
The applicability of anaerobic baffled reactor (ABR) was investigated for the treatment of acidic (pH 4.5–7.0) wastewater containing sulfate (1000–2000 mg/L) and Zn (65–200 mg/L) at 35 °C. The ABR consisted of four equal stages and lactate was supplemented (COD/SO42− = 0.67) as carbon and energy source for sulfate reducing bacteria (SRB). The robustness of the system was studied by decreasing pH and increasing Zn, COD, and sulfate loadings. Sulfate-reduction efficiency quickly increased during the startup period and reached 80% within 45 days. Decreasing feed pH, increasing feed sulfate and Zn concentrations did not adversely affect system performance as sulfate reduction and COD removal efficiencies were within 62–90% and 80–95%, respectively. Although feed pH was steadily decreased from 7.0 to 4.5, effluent pH was always within 6.8–7.5. Over 99% Zn removal was attained throughout the study due to formation of Zn-sulfide precipitate. 相似文献
145.
Sulfur-containing 3,5-disubstituted boron dipyrromethene (Bodipy®) fluorescent probes with improved water solubility were synthesized. A dicarboxylic acid derivative that can be excited by the 543 nm HeNe laser line is very soluble in aqueous solution and retains high fluorescence quantum yield of the unionizable parent molecule. Conversion of the dicarboxylic acid to the succimidyl or sulfosuccinimidyl diester produces molecules capable of labeling proteins with a bright and stable fluorescence signal. 相似文献
146.
Background
The constant increase of cancer cell resistance to radio- and chemotherapy hampers improvement of patient survival and requires novel targeting approaches. Integrin-Linked Kinase (ILK) has been postulated as potent druggable cancer target. On the basis of our previous findings clearly showing that ILK transduces antisurvival signals in cells exposed to ionizing radiation, this study evaluated the impact of the small molecule inhibitor QLT0267, reported as putative ILK inhibitor, on the cellular radiation survival response of human head and neck squamous cell carcinoma cells (hHNSCC).Methodology/Principal Findings
Parental FaDu cells and FaDu cells stably transfected with a constitutively active ILK mutant (FaDu-IH) or empty vectors, UTSCC45 cells, ILK floxed/floxed(fl/fl) and ILK −/− mouse fibroblasts were used. Cells grew either two-dimensionally (2D) on or three-dimensionally (3D) in laminin-rich extracellular matrix. Cells were treated with QLT0267 alone or in combination with irradiation (X-rays, 0–6 Gy single dose). ILK knockdown was achieved by small interfering RNA transfection. ILK kinase activity, clonogenic survival, number of residual DNA double strand breaks (rDSB; γH2AX/53BP1 foci assay), cell cycle distribution, protein expression and phosphorylation (e.g. Akt, p44/42 mitogen-activated protein kinase (MAPK)) were measured. Data on ILK kinase activity and phosphorylation of Akt and p44/42 MAPK revealed a broad inhibitory spectrum of QLT0267 without specificity for ILK. QLT0267 significantly reduced basal cell survival and enhanced the radiosensitivity of FaDu and UTSCC45 cells in a time- and concentration-dependent manner. QLT0267 exerted differential, cell culture model-dependent effects with regard to radiogenic rDSB and accumulation of cells in the G2 cell cycle phase. Relative to corresponding controls, FaDu-IH and ILK fl/fl fibroblasts showed enhanced radiosensitivity, which failed to be antagonized by QLT0267. A knockdown of ILK revealed no change in clonogenic survival of the tested cell lines as compared to controls.Conclusions/Significance
Our data clearly show that the small molecule inhibitor QLT0267 has potent cytotoxic and radiosensitizing capability in hHNSCC cells. However, QLT0267 is not specific for ILK. Further in vitro and in vivo studies are necessary to clarify the potential of QLT0267 as a targeted therapeutic in the clinic. 相似文献147.
We aimed to evaluate the mutagenic effect of Anilofos, organophosphate pesticide, by using Ames/Salmonella/microsome test. Its cytotoxic and genotoxic effects were also determined by chromosome aberration (CA), sister chromatid exchange (SCE) and micronucleus (MN) test in human peripheral blood lymphocytes. In the Ames test, five different concentrations of Anilofos were examined on TA97, TA98, TA100 and TA102 strains in the absence and presence of S9 fraction. According to the results all concentrations of this pesticide have not shown any mutagenic activity on TA97, TA100 and TA102 strains in the absence and presence of S9 fraction. But, 10, 100 and 1000 µg/plate concentrations of Anilofos were determined to be mutagenic on TA98 strain without S9 fraction. Lymphocytes were treated with various concentrations (25, 50, 100 and 200 µg/ml) of Anilofos for 24 and 48 h. The results of the assays showed that Anilofos did not induce SCE frequency, replication index and MN formation at all concentrations for both treatment periods. Anilofos significantly increased CA frequency at 100 and 200 µg/ml concentrations at 24 h treatment periods and at 50, 100 and 200 µg/ml concentrations in 48 h treatment periods. Additionally, it was determined that this pesticide decreased mitotic index and nuclear division index significantly. It was concluded that Anilofos has genotoxic and cytotoxic effects in human peripheral lymphocytes. 相似文献
148.
The effects of operating conditions on the enzymatic hydrolysis of corn starch were investigated. A commercial α-amylase produced by Bacillus sp. was used for the hydrolysis experiments. The degree of starch hydrolysis (%) and residual α-amylase activity (%) was investigated versus process variables, including pH, temperature, viscosity, impeller speed, processing time and some materials added such as hydrolysate, maltose, glucose, ethanol and CaCl2 using a stirred batch reactor. The mathematical models depending on the operating conditions were also derived using the experimental data of residual starch concentration. Some inactivation models were tested to determine the relationship between process variables and enzyme stability during the hydrolysis process. 相似文献
149.
Naziroğlu M Uğuz AC Gokçimen A Bülbül M Karatopuk DU Türker Y Cerçi C 《Neurochemical research》2008,33(9):1832-1837
We investigated effects of two doses of Tenoxicam, a type 2 cyclooxygenase inhibitor, administration on lipid peroxidation
and antioxidant redox system in cortex of the brain in rats. Twenty-two male Wistar rats were randomly divided into three
groups. First group was used as control. 10 and 20 mg/kg body weight Tenoxicam were intramuscularly administrated to rats
constituting the second and third groups for 10 days, respectively. Both dose of Tenoxicam administration resulted in significant
increase in the glutathione peroxidase activity, reduced glutathione and vitamins C and E of cortex of the brain. The lipid
peroxidation levels in the cortex of the brain were significantly decreased by the administration. Vitamin A and β-carotene
concentration was not affected by the administration. There was no statistical difference in all values between 10 and 20 mg
Tenoxicam administrated groups. In conclusion, treatment of brain with 10 and 20 mg Tenoxicam has protective effects on the
oxidative stress by inhibiting free radical and supporting antioxidant redox system. 相似文献
150.
Dilek Gogas Yavuz Halil ?nder Ers?z Mürvet Tuncel Mustafa F. Sargon Belgin Kü?ükkaya Rengin Ahiskali Sema Akalin 《Experimental diabetes research》2001,2(3):225-232
We investigated the effect of aminoguanidine (AG)
administration on GBM thickness, glomerular heparan
sulfate (HS) content, and urinary albumin and
HS excretion in diabetic rats. After induction of
diabetes, female Wistar rats were divided into 2
groups: Group AGDM (n=11) received 1g/L aminoguanidine
bicarbonate in drinking water, group DC
(n=12) was given only tap water. Control rats received
AG (group AGH, n=8) or tap water (group
HC, n=8). At the end of a period of 8 weeks,
urinary albumin and glycosaminoglycan (GAG)
excretion was detected. GBM heparan sulfate distribution
and count was determined under the electron
microscope. The AGDM group had lower
urinary albumin and GAG excretion than diabetic
controls. GBM thickness was increased in diabetic
rats compared to groups of AGDM and HC. In
AGDM group alcian blue stained particle distribution
and count in the GBM was similar to healthy
controls. In conclusion AG prevents the decrease
of anionic charged molecules in the GBM and
GBM thickening. This can be one of the mechanisms
by which AG decreases albuminuria in diabetic
rats. 相似文献