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951.
海栖热袍菌极端耐热木聚糖酶B的提纯 总被引:6,自引:0,他引:6
克隆并在大肠杆菌中表达的海栖热袍菌的 xyn B基因 ,其表达产物木聚糖酶 B的 C 末端带有 6×His标签 ,研究了这种基因重组酶的提纯方法。通过对粗酶提取液的热变性处理 ,Ni NTA亲和柱层析和离子柱层析 ,最终得到了电泳纯的木聚糖酶 B,提纯倍数 4 4.4 ,得率 11。SDS PAGE法测定木聚糖酶 B的相对分子质量为 4 2 ku,与理论推算值 4 2 333u相吻合 相似文献
952.
953.
Mehdi Ghahartars Shabnam Abtahi Zahra Zeinali Mohammad Javad Fattahi Abbas Ghaderi 《Iranian Biomedical Journal》2021,25(2):88
Background:TNF-α and IL-6 are both pleiotropic cytokines playing major roles in cancer-associated cytokine networks. They have previously been investigated for their function in skin malignancies, mostly melanomas, and studies on NMSC patients are relatively rare. In this study, we aimed to assess the associations of serum levels of IL-6 and TNF-α with NMSCs and its clinicopathological features. Methods:This cases-control study was carried out to investigate the serum levels of TNF-α and IL-6 in 70 NMSC patients, in comparison with 30 healthy individuals, by means of flow cytometric bead-based immuneoassay. Results:Serum levels of both TNF-α and IL-6 were significantly higher in NMSC patients (6.470 vs. 4.355 pg/ml; p = 0.0468, respectively), compared to healthy individuals (3.205 vs. 0.000 pg/ml; p = 0.0126, respectively). In the subgroup analysis, SCC patients had higher serum levels of IL-6 compared to healthy individuals (3.445 vs. 0.000 pg/ml; p = 0.0432). No other significant differences were observed in the serum levels of these two cytokines among different clinicopathological subgroups of the patients. Conclusion:The increased levels of TNF-α and IL-6 in NMSC patients can be introduced as an epiphenomenon of a complex cancer-induced cytokine cascade. Key Words: Biomarkers, Cytokines, Interleukin-6, Tumor Necrosis Factor-alpha 相似文献
954.
Multifunctional modification of wool fabric using graphene/TiO<Subscript>2</Subscript> nanocomposite
Mohammad?Ali?Shirgholami Loghman?KarimiEmail author Mohammad?Mirjalili 《Fibers and Polymers》2016,17(2):220-228
In this study, a new finishing technique is introduced through treatment of wool fabric with graphene/TiO2 nanocomposite. Graphene oxide/titanium dioxide nanocomposite first applied on the wool fabric by hydrolysis of titanium isopropoxide in graphene oxide suspension and then this coating chemically converted by sodium hydrosulfite to graphene/TiO2 nanocomposite. The homogenous distribution of the graphene/TiO2 nanocomposite on the fiber surface was confirmed by field emission scanning electron microscopy (FE-SEM), Energy-dispersive X-ray spectroscopy (EDS) and X-ray mapping. X-ray diffraction patterns proved the presence of titanium dioxide nanoparticles with a crystal size of 127 Å on the treated wool fabric. Also, the defect analysis based on X-ray photoelectron spectroscopy (XPS) established the composition of the nanocomposite. Other characteristics of treated fabrics such as antibacterial activity, photo-catalytic self-cleaning, electrical resistivity, ultraviolet (UV) blocking activity and cytotoxicity were also assessed. The treated wool fabrics possess significant antibacterial activity and photo-catalytic self-cleaning property by degradation of methylene blue under sunlight irradiation. Moreover, this process has no negative effect on cytotoxicity of the treated fabric even reduces electrical resistivity and improves UV blocking activity. 相似文献
955.
In this paper, the surface of magnetic manganese ferrite nanoparticles (MFN) was modified using cetyl trimethylammonium bromide (CTAB). The modified MFN was studied using Fourier transform infrared spectroscopy (FTIR). The adsorption capacity of surface modified MFN (MFN-CTAB) was investigated for dye removal for single and ternary systems. Three anionic dyes, C.I. Direct Red 80 (DR80), C.I. Direct Red 31 (DR31), and C.I. Acid Blue 92 (AB92), were used as model compounds. The effects of operational parameters on dye removal (i.e. adsorbent dosage, dye concentration and salt) and the kinetic and isotherm of dye adsorption were studied. The adsorption kinetic for the dyes was found to be well described by the pseudo-second order model. The maximum dye adsorption capacity (Q 0) of MFN-CTAB for DR80, DR31 and AB92 was 83 mg/g, 59 mg/g and 70 mg/g, respectively. The adsorption isotherm data were analyzed using the Langmuir, Freundlich, and Temkin equations. The results revealed that the Langmuir model fitted the adsorption data better. The results showed that the MFN-CTAB as a magnetic adsorbent might be a suitable alternative to remove dyes from colored aqueous solutions. 相似文献
956.
Exon Sequencing of PKD1 Gene in an Iranian Patient with Autosomal-Dominant Polycystic Kidney Disease
Atousa Hafizi Saeid Reza Khatami Hamid Galehdari Gholamreza Shariati Ali Hossein Saberi Mohammad Hamid 《Iranian Biomedical Journal》2014,18(3):143-150
Introduction: Autosomal dominant polycystic kidney disease (ADPKD) is one of the most common genetic kidney disorders with the incidence of 1 in 1,000 births. ADPKD is genetically heterogeneous with two genes identified: PKD1 (16p13.3, 46 exons) and PKD2 (4q21, 15 exons). Eighty five percent of the patients with ADPKD have at least one mutation in the PKD1 gene. Genetic studies have demonstrated an important allelic variability among patients, but very few data are known about the genetic variation among Iranian populations. Methods: In this study, exon direct sequencing of PKD1 was performed in a seven-year old boy with ADPKD and in his parents. The patient’s father was ADPKD who was affected without any kidney dysfunction, and the patient’s mother was congenitally missing one kidney. Results: Molecular genetic testing found a mutation in all three members of this family. It was a missense mutation GTG>ATG at position 3057 in exon 25 of PKD1. On the other hand, two novel missense mutations were reported just in the 7-year-old boy: ACA>GCA found in exon 15 at codon 2241 and CAC>AAC found in exon 38 at codon 3710. For checking the pathogenicity of these mutations, exons 15, 25, and 38 of 50 unrelated normal cases were sequenced. Conclusion: our findings suggested that GTG>ATG is a polymorphism with high frequency (60%) as well as ACA>GCA and CAC>AAC are polymorphisms with frequencies of 14% and 22%, respectively in the population of Southwest Iran. Key Words: Autosomal dominant polycystic kidney disease (ADPKD), Polycystic kidney diseases (PKD), PKD1 gene, Iran 相似文献
957.
Fatemeh Mohammadi Mohammad Shafiei Dlnya Assad Golale Rostami Mohammad Hamid Ali Mohammad Foroughmand 《Iranian Biomedical Journal》2021,25(1):54
Background:IM, a strong and selective TKI, has been approved as the front line of treatment in CML patients. In spite of satisfactory results of imatinib in the treatment of patients with CML, patients with treatment failure or suboptimal response developed resistance that might be because of pharmacogenetic variants. This study attempted to evaluate the influence of ABCB1 gene polymorphisms and smoking on CML risk and resistance to imatinib. Methods: ABCB1 (c.1236C>T, c.3435C>T) polymorphisms were genotyped in 98 CML patients and 100 sex- and age-matched healthy subjects by PCR-RFLP method, followed by sequencing. The patients were evaluated for cytogenetic response by the standard chromosome banding analysis in regular intervals. Results:Our results showed that c.1236CC genotype was significantly associated with imatinib resistance (OR = 3.94; p = 0.038). Analysis of the joint of SNP-smoking combination showed that smokers with c.1236TT/CT and c.1236CC genotypes had the increased risk of CML (OR = 6.04; p = 0.00 and OR = 4.95, p = 0.005) and treatment failure (OR = 5.36, p = 0.001 and OR = 15.7, p = 0.002), respectively. Smokers with c.3435TT/CT and c.3435CC genotypes also displayed the elevated risk of CML development (OR = 6.01, p = 0 and OR = 4.36, p = 0.011) and IM resistance (OR = 5.61, p = 0.001 and OR = 13.58, p = 0.002), respectively. Conclusion:Our findings suggest that c.1236CC genotype has clinical importance in the prediction of treatment outcome with IM, and smoking could have a synergistic role in CML risk and IM resistance. Key Words: ATP binding cassette transporter subfamily B, Imatinib mesylate, Smoking 相似文献
958.
Asemi Z Jazayeri S Najafi M Samimi M Mofid V Shidfar F Foroushani AR Shahaboddin ME 《Pakistan journal of biological sciences: PJBS》2011,14(8):476-482
Previous studies have shown that inflammatory factors increases in pregnancy and is associated with several complications of pregnancy. The aim of this study was to assess effects of daily consumption of probiotic yoghurt on inflammatory factors in pregnant women. In a randomized clinical trial, seventy primigravid (the first pregnancy) and singleton pregnant women aged 18-30 years were assigned to two groups. Subjects consumed daily 200 g probiotic yoghurt containing Lactobacillus acidophilus La5 and Bifidobacterium animalis BB12 (10(7) CFU g(-1) for each) or 200 g conventional yoghurt for 9 weeks. Fasting blood samples were collected at baseline (28 weeks of gestation) and after intervention (37 weeks of gestation). Inflammatory factors, hs-CRP and TNF-alpha, were measured by Enzyme-linked Immunosorbent Assay (ELISA). Independent t-test was used to compare the two groups after intervention and paired-sample t-test compared variables before and after treatment. The results showed that the probiotic yogurt brought about a decrease in the serum hs-CRP level, from 10.44 +/- 1.56 to 7.44 +/- 1.03 microg mL(-1) (p = 0.041). There was no significant change in the conventional yogurt group in the serum hs-CRP level (12.55 +/- 1.57 to 14.51 +/- 1.62 microg mL(-1), p = 0.202). The probiotic yogurt had no effect on TNF-alpha (from 73.75 +/- 6.59 to 77.91 +/- 5.61 pg mL(-1), p = 0.633). Serum TNF-alpha did not change in the conventional yogurt group (p = 0.134). In conclusion probiotic yogurt significantly decreased hs-CRP in pregnant women but had no effect on TNF-alpha. 相似文献
959.
960.
BACKGROUND: Progressive cognitive decline is one of the hallmark symptoms of Alzheimer's disease (AD) which can be modeled by beta-amyloid injection into specific regions of brain. Since epigallocatechin-3-gallate (EGCG) is a potent antioxidant agent which its role against oxidative stress and inflammation has been shown in prior studies, we tried to determine whether EGCG administration protects against beta-amyloid-induced memory and coordination impairment in rats. METHODS: Animals (male Wistar rats) were divided into four groups: sham operated, EGCG-pretreated sham operated (sham+EGCG), untreated lesion (lesion), and EGCG-pretreated lesion (lesion+EGCG). Animals in lesion, lesion+EGCG, and sham+EGCG groups received sterile saline or saline plus EGCG (10 mg/kg) intraperitoneally one day pre-surgery and every other day for three weeks. The lesion was induced one day after EGCG pretreatment by injection of 4 microl of sterile saline or water containing 2 nmol/microl beta-amyloid (1-40) into the hippocampal fissure. For behavioral analysis, psychomotor coordination (PMC) index and spontaneous alternation behavior were assessed using Rota-rod Treadmill and Y-maze, respectively at the third week post-lesion. RESULTS: We found that beta-amyloid (1-40) injection into hippocampus can decrease these behavioral indexes in lesion group in comparison with sham group which is similar to behavioral changes in AD. On the other hand, pretreatment with EGCG can improve the PMC index and spatial Y-maze alternation in the lesion+EGCG group in comparison with lesion group. CONCLUSION: We concluded that EGCG can be effective in restoring beta-amyloid-induced behavioral derangements in rats regarding coordination and memory abilities. 相似文献