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91.
There is a growing research interest on products with antimicrobial activity. Antimicrobial polymers are one of the most surefire procedures to combat microbes. In the present study, the ability of Βeta-casein- one of the milk major self assembly proteins with high polymeric film production capability—as a fusion partner of Ib-AMP4 antimicrobial peptide was investigated. Also, the antimicrobial activities of Βeta-casein- IbAMP4 fusion protein antimicrobial against common food pathogens were assessed. The pET21a-BCN-Ib-AMP 4 construct was transformed to Escherichia coli BL21 (DE3), and protein expression was induced under optimized conditions. Purified protein obtained from nickel affinity chromatography was refolded under optimized dialysis circumstances and concentrated to 1600 µg mL?1 fusion protein by ultrafiltration. 5 μg mL?1 H2O2 was applied for accelerating the formation of two necessary disulfide bonds. Antimicrobial assays were performed against E. coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus, Aspergillus flavus and Candida albicans. Results of antimicrobial tests confirmed the efficiency of BCN-IbAMP4 against all tested microorganisms. Overall, the combination of thymol plus BCN-IbAMP4 increased their antimicrobial activities. MIC, MBC, MFC, FICI and FBCI values showed strong synergistic activity between the two examined compounds. Time kill and growth kinetic studies indicated significant reduction of cell viability during first period of exposure to BCN-IbAMP4 and thymol combination.  相似文献   
92.
Human papillomavirus (HPV) is a common viral infection worldwide associated with a variety of cancers. The integration of the HPV genome in these patients causes chromosomal instability and triggers carcinogenesis. The aim of this study was to investigate the HPV-16 genome physical status in four major cancers related to HPV infection. Formalin-fixed paraffin-embedded blocks from our previous projects on head and neck, colorectal, penile, and cervical cancers were collected, and HPV-16–positive specimens were used for further analysis. The DNA extraction copy number of E2 and E7 genes was calculated by qualitative real-time PCR method. Serially diluted standards that were cloned in PUC57 plasmid were used. Standard curve and melting curve analysis was used for quantification. Of the 672 specimens studied, 76 (11.3%) were HPV-16 positive. We found that 35.6% (16/45) were integrated. Statistical analysis showed that there were significant correlations between integration of HPV-16 and cervical cancer end-stage carcinogenesis (P < .0001), episomal form, and ASCUS lesions (P = .045). Significant correlation in penile cancer patients was seen between the episomal form and high-grade cancer stage (P = .037). Integration is a major factor in the carcinogenesis mechanism of HPV and has different prevalence in various cancers with a higher rate in progression except in penile cancer.  相似文献   
93.
Several pathways involved in regulation of intracellular protein integrity are known as the protein quality control (PQC) system. Molecular chaperones as the main players are engaged in various aspects of PQC system. According to the importance of these proteins in cell survival, in the present study, we traced endoplasmic reticulum-specific markers and chaperone-mediated autophagy (CMA)-associated factors as two main arms of PQC system in intra-hippocampal amyloid beta (Aβ)-injected rats during 10 days running. Data analysis from Western blot indicated that exposure to Aβ activates immunoglobulin heavy-chain-binding protein (Bip) which is the upstream regulator of unfolded protein responses (UPR). Activation of UPR system eventually led to induction of pro-apoptotic factors like CHOP, calpain, and caspase-12. Moreover, our data revealed that protein disulfide isomerase activity dramatically decreased after Aβ injection, which could be attributed to the increased levels of nitric oxide. Besides, Aβ injection induced levels of 2 members of heat shock proteins (Hsp) 70 and 90. Elevated levels of Hsps family members are accompanied by increased levels of lysosome-associated membrane protein type-2A (Lamp-2A) that are involved in CMA. Despite the reduction in CHOP, calpain, caspase-12, and Lamp-2A protein levels, the levels of molecular chaperones Bip, Hsps70, and 90 increased 10 days after Aβ injection in comparison to the control group. Based on our results, 10 days after Aβ injection, despite the activation of protective chaperones, markers associated with neurotoxicity were still elevated.  相似文献   
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It has recently been reported that bilirubin forms a complex with Cu(II). In this paper we show that the formation of the complex results in the reduction of Cu(II) to Cu(I) and the redox cycling of the metal gives rise to the formation of reactive oxygen species, particularly hydroxyl radical. The bilirubin-Cu(II) complex causes strand breakage in calf thymus DNA and supercoiled plasmid DNA. Cu(I) was shown to be an essential intermediate in the DNA cleavage reaction by using the Cu(I) specific sequestering reagent neocuproine. Bilirubin-Cu(II) produced hydroxyl radical and the involvement of active oxygen species was established by the inhibition of DNA breakage by various oxygen radical quenchers.  相似文献   
97.
Despite differences in the anatomical and physiological characteristics of the medial gastrocnemius (MG), lateral gastrocnemius (LG), and soleus (Sol) muscles, it is common practice to investigate them as single triceps surae H-reflex recordings. The aim of this study was to compare the latencies of H-reflex recordings from the Sol, MG, and LG in patients with explicit magnetic resonance imaging (MRI) evidence of unilateral S1 radiculopathy and also compare their diagnostic yield in varied clinical characteristics (i.e., symptom duration and severity of involvement). We found a significant difference between H-reflex latencies of Sol and the two others (p?相似文献   
98.
This study addresses the biodiversity profile of bacterial community in the intestinal lumen and mucosa of snow trout fish by applying 16S rRNA gene 454-pyrosequencing. A total of 209,106 sequences with average length 689 (±53) were filtered, denoised, trimmed, and then sorted into OTUs based on 97 % sequence similarity using the USEARCH software pipeline. Bacteria representing 10 phyla were found in the samples investigated. Fimicutes ribotypes were present in intestinal-mucosa and lumen in all fish and often dominated the libraries (average 43 and 38 %, respectively). Proteobacteria were also prevalent, but at a lower relative abundance, at 22 and 29 % in mucosa and lumen, respectively. The autochthonous microbiota was dominated by sequences belonging to the Bacilli (mean sequence abundance 24 %), in particular the Lactobacillaceae, with Lactobacillus and Pediococcous being the most abundant genera. Fewer Bacilli (mean sequence abundance 22 %) and Actinobacteria (2 %) were present in the lumen, and allochthonous communities consisted of a more even split among the bacterial classes, with increases in sequences assigned to members of the γ-Proteobacteria (16 %) and Fusobacteriia (8 %). The principal bacterial genera recorded in the lumen belonged to the lactic acid bacteria group, Cetobacterium, Clostridium and Synechococcus. Results obtained suggest that the lumen and mucosal layer of the snow trout intestine may host different microbial communities. Moreover, both regions harbour a diverse microbiome with a greater microbial diversity in the intestinal mucus compared with the luminal communities of the fish. Many of these microbes might be of high physiological relevance for the fish and may play key roles in the functioning of its gut.  相似文献   
99.
According to our analysis of literature sources on the family Hydraenidae (Coleoptera: Staphylinoidea) of Iran, it is represented by 67 species and three genera: Hydraena Kugelann, 1794 (21 species), Limnebius Leach, 1815 (six species) and Ochthebius Leach, 1815 (40 species). Twenty-two species are supposed to be endemic to Iran. Here, for the first time, we summarize species distribution data in Iranian provinces and present them in a checklist of Iranian Hydraenidae. We also present two additional species lists: one with incorrect records (one species and one subspecies) and the other with unidentified species.  相似文献   
100.
Well-defined polymer scaffolds convertible to (multi)functional polymer structures via selective and efficient modifications potentially provide an easy, versatile, and useful approach for a wide variety of applications. Considering this, a homopolymer scaffold, poly(pyridyldisulfide ethylmethacrylate) (poly(PDSM)), having pendant groups selectively reactive with thiols, was synthesized by reversible addition fragmentation chain transfer (RAFT) polymerization. Soluble polymers with controlled molecular weights and narrow PDIs were generated efficiently. The versatility of the scaffold to generate random co- and ter-polymers combining multiple functionalities with controlled-composition was shown by separate and simultaneous conjugation of different mercapto-compounds, including a tripeptide in one-step. Conversion of water-insoluble scaffold to peptide-containing water-soluble copolymers was observed to yield nanometer-size particles with narrow polydispersity. The overall results suggest that the well-defined PDSM homopolymer scaffold generated via RAFT polymerization can be a versatile building block for generation of new structures having potential for drug delivery applications via a straightforward synthetic approach.  相似文献   
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