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Herpes Simplex Virus Type 1 (HSV-1) is a ubiquitous pathogen. Other than known diseases, HSV-1 may have an important role in the pathogenesis of atopy by causing immortality of th2 cells. From June 1st to July 31st 2006, seventy five blood samples were collected from atopic children referred to the allergy clinic of the hospital. The bloods samples were used to detect HSV-1 IgG antibodies by Enzyme-Linked Immunosorbent Assay and Virus Neutralization Test. HSV-1 IgG antibody seroprevalence in atopic children was found high, 62.6% by Enzyme-Linked Immunosorbent Assay and 57.3% by Virus Neutralization Test. Thus Virus Neutralization Test sensitivity was 92.15% and specificity was 100% regarding to the Enzyme-Linked Immunosorbent Assay technic. Although Enzyme-Linked Immunosorbent Assay was more sensitive than Virus Neutralization Test, there was no significant difference between two technics (p > 0.05) in detecting HSV-1 IgG antibodies in serum.  相似文献   
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Protection of the patients against the side effects of chemotherapy and radiotherapy regimens has attracted increasing interest of clinicians and practitioners. Caffeic acid phenethyl ester (CAPE), which is extracted from the propolis of honeybee hives as an active component, specifically inhibits nuclear factor κB at micromolar concentrations and show ability to stop 5‐lipoxygenase‐catalysed oxygenation of linoleic acid and arachidonic acid. CAPE has antiinflammatory, antiproliferative, antioxidant, cytostatic, antiviral, antibacterial, antifungal and antineoplastic properties. The purpose of this review is to summarize in vivo and in vitro usage of CAPE to prevent the chemotherapy‐induced and radiotherapy‐induced damages and side effects in experimental animals and to develop a new approach for the potential usage of CAPE in clinical trial as a protective agent during chemotherapy and radiotherapy regimens. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
4.
Prostate cancer is a common malignancy that develops by structural mutation(s) and/or other genetic alterations in specific genes.The G to T transversions in codon 12 and C to T transitions in codon 13 of KRAS proto-oncogene are predominant point mutations that occur in about 20% of different cancers in human. In the current study it was aimed to investigate the prevalence and predictive significance of KRAS mutations in patients with prostate carcinomas. In a total of 30 fresh tumoural tissue specimens were investigated in patients with prostate carcinoma. All tumoural specimens were histo-pathologically diagnosed and genotyped for codon 12, 13 KRAS point mutations by reverse hybridisation and direct sequencing methods. KRAS mutations were found in 12 (40%) samples with 29 samples deriving from adenocarcinomas and 1 sample was small cell prostate carcinoma. In 1 (3.44%) sample codon 12 was found to be mutated and in 2 (6.8%) samples codon 13 and in 9 (31%) samples combined codon 12 and 13 were found to be mutated particularly in higher grade of tumoural tissues. Our study, based on representative collection of human prostate tumours, indicates that combined mutations in codons 12 and 13 KRAS are relatively infrequent and most commonly occur in prostate carcinomas.  相似文献   
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A novel gene sequence, with two exons and one intron, encoding a metallothionein (MT) has been identified in durum wheat Triticum durum cv. Balcali85 genomic DNA. Multiple alignment analyses on the cDNA and the translated protein sequences showed that T. durum MT (dMT) can be classified as a type 1 MT. dMT has three Cys-X-Cys motifs in each of the N- and C-terminal domains and a 42-residue-long hinge region devoid of cysteines. dMT was overexpressed in Escherichia coli as a fusion protein (GSTdMT), and bacteria expressing the fusion protein showed increased tolerance to cadmium in the growth medium compared with controls. Purified GSTdMT was characterized by SDS- and native-PAGE, size exclusion chromatography, and matrix-assisted laser desorption ionization time-of-flight mass spectrometry. It was shown that the recombinant protein binds 4 +/- 1 mol of cadmium/mol of protein and has a high tendency to form stable oligomeric structures. The structure of GSTdMT and dMT was investigated by synchrotron x-ray solution scattering and computational methods. X-ray scattering measurements indicated a strong tendency for GSTdMT to form dimers and trimers in solution and yielded structural models that were compatible with a stable dimeric form in which dMT had an extended conformation. Results of homology modeling and ab initio solution scattering approaches produced an elongated dMT structure with a long central hinge region. The predicted model and those obtained from x-ray scattering are in agreement and suggest that dMT may be involved in functions other than metal detoxification.  相似文献   
6.
Ozturk Urek  Raziye  Ilgin  Seda 《Annals of microbiology》2019,69(11):1201-1210
Microbial exopolysaccharides (EPSs) are very important because they are used in biotechnological applications in different industrial areas. The aim of the study was to determine the best EPS producer Pleurotus sp., to optimize EPS production and to perform partial purification and characterization of the produced EPS. After the production conditions were optimized, the EPS was isolated and partially purified. EPS was characterized by HP-TLC, 1H-NMR, FT-IR, and TGA. Hydroxyl, superoxide, and DPPH radical scavenging activities of the EPS were also investigated spectrophotometrically. The best EPS producer and its incubation period in submerged fermentation were determined as Pleurotus sajor caju and on 5 days, respectively. Culture conditions to increase EPS production were optimized as follows (in per liter): 90 g of glucose, 10 g of yeast extract, 10 g of peptone, and 100 mM of Mg2+. The optimal initial pH, temperature, and an agitation rate of culture were determined as 5.0, 25 °C, and 150 rate min−1, respectively. The highest EPS production was determined as 33.32 ± 1.6 g L−1. After isolation of EPS, one active fraction was obtained by gel filtration chromatography. EPS is composed mainly of glucose according to HP-TLC analysis. To the results, EPS had a complex structure by having carbohydrate and protein contents. The produced EPS had high degradation temperature as well as high antioxidant activity.  相似文献   
7.
Engineering challenges in high density cell culture systems   总被引:2,自引:0,他引:2  
Ozturk SS 《Cytotechnology》1996,22(1-3):3-16
High density cell culture systems offer the advantage of production of bio-pharmaceuticals in compact bioreactors with high volumetric production rates; however, these systems are difficult to design and operate. First of all, the cells have to be retained in the bioreactor by physical means during perfusion. The design of the cell retention is the key to performance of high density cell culture systems. Oxygenation and media design are also important for maximizing the cell number. In high density perfusion reactors, variable cell density, and hence the metabolic demand, require constant adjustment of perfusion rates. The use of cell specific perfusion rate (CSPR) control provides a constant environment to the cells resulting in consistent production. On-line measurement of cell density and metabolic activities can be used for the estimation of cell densities and the control of CSPR. Issues related to mass transfer and mixing become more important at high cell densities. Due to the difference in mass transfer coefficients for oxygen and CO2, a significant accumulation of dissolved CO2 is experienced with silicone tubing aeration. Also, mixing is observed to decrease at high densities. Base addition, if not properly done, could result in localized cell lysis and poor culture performance. Non-uniform mixing in reactors promotes the heterogeneity of the culture. Cell aggregation results in segregation of the cells within different mixing zones. This paper discusses these issues and makes recommendations for further development of high density cell culture bioreactors.  相似文献   
8.
The embryonic poly(A)-binding protein (EPAB) functions in the translational regulation of the maternal messenger RNAs (mRNAs) required during oocyte maturation, fertilization, and early embryo development. Since there is no antibody specific to mammalian EPAB protein, all studies related to the Epab gene could be performed at the mRNA levels except for the investigations in the Xenopus. In this study, we have produced an EPAB-specific antibody. When we examined its expressional distribution in the mouse gonadal and somatic tissues, the EPAB protein was found to be expressed only in the mouse ovary and testis tissues, but it is undetectable level in the somatic tissues including stomach, liver, heart, small intestine, and kidney. Additionally, the spatial and temporal expression patterns of the EPAB and poly(A)-binding protein cytoplasmic 1 (PABPC1) proteins were analyzed in the mouse germinal vesicle (GV) and metaphase II (MII) oocytes, one-cell, and two-cell embryos. While EPAB expression gradually decreased from GV oocytes to two-cell embryos, the PABPC1 protein level progressively increased from GV oocytes to one-cell embryos and remarkably declined in the two-cell embryos ( P < 0.05). We have also described herein that the EPAB protein interacted with Epab, Pabpc1, Ccnb1, Gdf9, and Bmp15 mRNAs dependent upon the developmental stages of the mouse oocytes and early embryos. As a result, we have first produced an EPAB-specific antibody and characterized its expression patterns and interacting mRNAs in the mouse oocytes and early embryos. The findings suggest that EPAB in cooperation with PABPC1 implicate in the translational control of maternal mRNAs during oogenesis and early embryo development.  相似文献   
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We tested whether zoledronic acid, a biphosphonate with proposed apoptotic activity, augmented the cytotoxicity of cisplatin and/or gemcitabine in A549 lung cancer cell line. This cell line was subjected to different concentrations of the above chemotherapeutic agents and zoledronic acid. Cytotoxicity was assessed by the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide) assay. Particularly, zoledronic acid in 100 micromolar (microM) concentration augmented the cytotoxicity by cisplatin 1microg/ml from 25% to 70% (Z=3.22, P=0.0072). A significant portion of cells underwent apoptosis with or without zoledronic acid, but more so with the combination treatment as assessed by an Annexin V-FITC apoptosis detection kit. However, 100microM zoledronic acid showed 50% cytotoxicity on its own, but failed to improve cytotoxicity by Gemcitabine. Thus, we show for the first time in a lung cancer cell line that zoledronic acid bears cytotoxic potential on its own and in conjunction with cisplatin. The clinical potential of this finding should be further studied.  相似文献   
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