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821.
Medicinal plant-derived bioactive compounds have recently gained more interest in biological research as an important source of novel drug candidates. Phyllanthus acidus (L.) is a widely distributed herbal medicinal plant naturally used in Ayurvedic medicine in Bangladesh. The present study focused on exploring the biological potential as well as the inhibitory effect of EAC cell growth with a comparative analysis between Phyllanthus acidus fruit pulp and seed. Crude methanol extract of P. acidus (MEPA) fruit pulp and seed was assessed as DPPH and NO free radical scavengers. While Brine Shrimp lethality bioassay, the standard protocol of phytochemical screening and hemagglutination assay were performed successively to determine the toxic effect on normal cells, the identification of some crucial phytochemicals, and the existence of lectin protein. EAC (Ehrlich’s Ascites Carcinoma) cell growth inhibition was determined by hemocytometer and morphological changes of EAC cells were observed by a fluorescence microscope using Swiss albino mice. The IC50 value of MEPA fruit pulp and seed was obtained as 57.159 µg/ml and 288.743 µg/ml respectively where minimal toxic effects on Brine Shrimp nauplii demonstrates that it is a good source of natural antioxidant compounds. Again, MEPA fruit pulp and seed-mediated effective agglutination of mouse blood erythrocyte strongly support the presence of lectin protein. Furthermore, MEPA fruit pulp and seed extract-treated EAC cells showed 65.71% and 28.57% growth inhibition respectively. The fluorescent microscopic examination of EAC cells treated with MEPA fruit pulp has shown more remarkable structural changes in the nucleus than that of seed. Based on the above findings, the present study reveals that MEPA fruit pulp can be considered as a novel biological candidate for the treatment of fatal diseases shortly.  相似文献   
822.
International Journal of Peptide Research and Therapeutics - Epsilon toxin (ETX) is one of four lethal toxins of Clostridium perfringens produced by types B and D of the pathogen. This pore-forming...  相似文献   
823.

Early-stage gastrointestinal (GI) carcinomas are amenable malignancies, however, due to late diagnosis or lack of proper medication, alternative treatment necessitates new approaches such as dendritic cell (DC) therapy. Our previous microarray study indicated Lymphocyte antigen-6 (LY6E) as a commonly overexpressed biomarker in three lethal GI cancers, colon, gastric, and pancreatic. Therefore, we examined the antigenic potency of LY6E in stimulating DCs to elicit tumor-specific responses against human colorectal cancer (CRC) and gastric cancer (GC) cell lines HT-29 and AGS, respectively. LY6E peptide-pulsed DCs stimulated lymphocytes up to 55.9% in comparison with mature DCs (48.3%). Also, flow cytometry analysis of lymphocyte proliferation illustrated that the populations CD4+ and CD8+ were increased after treating by peptide-pulsed DCs (62.9% and 48.7% respectively). Furthermore, the cytotoxicity assay demonstrated that the 40:1 ratio of stimulated lymphocytes on AGS and HT29 cell lines was 65.1% and 66.2%, respectively. The research exposed that LY6E loaded DCs had substantial impact stimulation, proliferation, and lineage differentiation of lymphocytes. Besides, co-cultured of primed lymphocytes with AGS and HT29 cell lines exhibited cytotoxic activity. These data suggest LY6E as a potential candidate in developing DC therapy against CRC and AGS.

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824.

S3E3 is a new variant of S3 antimicrobial peptide (AMP) derived from factor C of horseshoe hemolymph and features a high binding affinity for endotoxin. In this research, site-specific conjugated S3E3 AMP onto Sepharose 6% solid phase support (S3E3-S-Sepharose) was applied for endotoxin removal from protein solutions. The bovine serum albumin (BSA) was chosen as a protein model due to its acidic-sticky nature interfering with the endotoxin removal process. The batch process parameters including, endotoxin concentration, pH, and ionic strength of the sample were optimized by response surface methodology to reach maximum endotoxin binding capacity and protein recovery. The predicted optimal conditions for enhanced endotoxin removal performance were as follows: pH 4.5, 25 mM NaCl, and 68,500 EU/ml endotoxin leading to a maximum endotoxin binding capacity of 3.114?×?10+6 EU/ml of resin and a 95.89% protein recovery. S3E3-S-Sepharose could be applied as an efficient endotoxin removal affinity chromatography matrix at downstream processes of recombinant therapeutics due to its high capacity and protein recovery.

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825.
A cell surface display system with metalbinding properties was previously developed using CS3 fimbriae, which are hollow tubes 20 nm-thick and 2 nm in diameter. In this study, hybrid CS3 pili were separated from recombinant Escherichia coli and entrapped in calcium alginate gel beads in order to improve their stabilization and also adsorption of heavy metals. The surface morphology of the gel beads containing pili was investigated by scanning electron microscopy (SEM). Immunofluorescence microscopy was employed to confirm the attachment of nanobiofibers to the alginate beads. The effects of three variables (sodium alginate concentration, protein to alginate mass ratio, and bead size) at two levels each on Cd2+ biosorption efficiency were investigated by full factorial experimental design. A second-order polynomial equation modeled the design space for the process response of cadmium removal capacity. The optimal values of the factors were obtained as follows: 1% sodium alginate concentration, 0.25 protein to alginate mass ratio, and a 6 mm bead size. Under these conditions, Cd2+ was adsorbed at 45.45 mg/g to the nanobiofiber. The results indicate that the immobilized recombinant hybrid CS3 pili may be an appropriate biosorbent for removal of heavy metals from polluted aquatic environments.  相似文献   
826.
Uropathogenic Escherichia coli (UPEC) bacteria are the principal cause of urinary tract infections (UTI). Because these bacteria propagate intracellularly, the cellular immune response is an important factor in UTIs. Therefore, we designed a genetic construct to induce a cellular immune response. In order to develop a genetic construct that induces strong cellular immunity against this pathogen, we used the fimH synthetic gene according to mammalian codon usage, and the gene expression was compared with wild type codon usage. Initially, we designed two constructs, pVAX/fimH mam and pVAX/fimH wt, which contain mammalian and wild type codon usage, respectively. The Cos-7 cell line was transfected separately with a complex of pVAX/fimH mam-ExGene 500 poly cationic polymer and pVAX/fimH wt-ExGene 500 poly cationic polymer. Expression of the fimH gene in both constructs in COS7 cells was confirmed by RT-PCR, SDS-PAGE, and Western blotting. Both of the pVAX/fimH cassettes expressed inserted fimH genes (mam and wt) in Cos-7 cells. Our results suggest that codon optimization successfully expressed the fimH gene because the fimH gene with mammalian codon usage is compatible with the eukaryotic expression system. Therefore, mammalian codon usage could be appropriate in a pVAX/fimH construct as a DNA vaccine.  相似文献   
827.
Increasing the level of physical fitness for competition is the primary goal of any conditioning program for wrestlers. Wrestlers often need to peak for competitions several times over an annual training cycle. Additionally, the scheduling of these competitions does not always match an ideal periodization plan and may require a modified training program to achieve a high level of competitive fitness in a short-time frame. The purpose of this study was to examine the effects of 4 weeks of sprint-interval training (SIT) program, on selected aerobic and anaerobic performance indices, and hormonal and hematological adaptations, when added to the traditional Iranian training of wrestlers in their preseason phase. Fifteen trained wrestlers were assigned to either an experimental (EXP) or a control (CON) group. Both groups followed a traditional preparation phase consisting of learning and drilling technique, live wrestling and weight training for 4 weeks. In addition, the EXP group performed a running-based SIT protocol. The SIT consisted of 6 35-m sprints at maximum effort with a 10-second recovery between each sprint. The SIT protocol was performed in 2 sessions per week, for the 4 weeks of the study. Before and after the 4-week training program, pre and posttesting was performed on each subject on the following: a graded exercise test (GXT) to determine VO(2)max, the velocity associated with V(2)max (νVO(2)max), maximal ventilation, and peak oxygen pulse; a time to exhaustion test (T(max)) at their νVO(2)max; and 4 successive Wingate tests with a 4-minute recovery between each trial for the determination of peak and mean power output (PPO, MPO). Resting blood samples were also collected at the beginning of each pre and posttesting period, before and after the 4-week training program. The EXP group showed significant improvements in VO(2)max (+5.4%), peak oxygen pulse (+7.7%) and T(max) (+32.2%) compared with pretesting. The EXP group produced significant increases in PPO and MPO during the Wingate testing compared with pretesting (p < 0.05). After the 4-week training program, total testosterone and the total testosterone/cortisol ratio increased significantly in the EXP group, whereas cortisol tended to decrease (p = 0.06). The current findings indicate that the addition of an SIT program with short recovery can improve both aerobic and anaerobic performances in trained wrestlers during the preseason phase. The hormonal changes seen suggest training-induced anabolic adaptations.  相似文献   
828.
Hutchinson-Gilford progeria syndrome (HGPS) is a premature aging syndrome caused by the expression and accumulation of a mutant form of lamin A, Δ50 lamin A. As a component of the cell's nucleoskeleton, lamin A plays an important role in the mechanical stabilization of the nuclear envelope and in other nuclear functions. It is largely unknown how the characteristic 50 amino acid deletion affects the conformation of the mostly intrinsically disordered tail domain of lamin A. Here we perform replica exchange molecular dynamics simulations of the tail domain and determine an ensemble of semi-stable structures. Based on these structures we show that the ZMPSTE 24 cleavage site on the precursor form of the lamin A tail domain orients itself in such a way as to facilitate cleavage during the maturation process. We confirm our simulated structures by comparing the thermodynamic properties of the ensemble structures to in vitro stability measurements. Using this combination of experimental and computational techniques, we compare the size, heterogeneity of size, thermodynamic stability of the Ig-fold, as well as the mechanisms of force-induced denaturation. Our data shows that the Δ50 lamin A tail domain is more compact and displays less heterogeneity than the mature lamin A tail domain. Altogether these results suggest that the altered structure and stability of the tail domain can explain changed protein-protein and protein-DNA interactions and may represent an etiology of the disease. Also, this study provides the first molecular structure(s) of the lamin A tail domain, which is confirmed by thermodynamic tests in experiment.  相似文献   
829.
Atherosclerosis and its consequences remain the main cause of mortality in industrialized and developing nations. Plaque burden and progression have been shown to be independent predictors for future cardiac events by intravascular ultrasound. Routine prospective imaging is hampered by the invasive nature of intravascular ultrasound. A noninvasive technique would therefore be more suitable for screening of atherosclerosis in large populations. Here we introduce an elastin-specific magnetic resonance contrast agent (ESMA) for noninvasive quantification of plaque burden in a mouse model of atherosclerosis. The strong signal provided by ESMA allows for imaging with high spatial resolution, resulting in accurate assessment of plaque burden. Additionally, plaque characterization by quantifying intraplaque elastin content using signal intensity measurements is possible. Changes in elastin content and the high abundance of elastin during plaque development, in combination with the imaging properties of ESMA, provide potential for noninvasive assessment of plaque burden by molecular magnetic resonance imaging (MRI).  相似文献   
830.
An ecosystem is a complex composition of physical, chemical and biological components. This complex system remains in a healthy state if the system can maintain the ecological equilibrium among its components. Anthropogenic disturbances are the prime stressors that affect this equilibrium through creating fragmentation, ecosystem sensitivity, loosening landscape connectivity and disrupting ecological integrity. As different types of ecosystem are interconnected, a comprehensive monitoring and evaluating criteria is needed for measuring its integrity at regional level for conservation planning. A Regional Index of Ecological Integrity can be a suitable approach for sustainable management of regional ecosystem. Therefore, this paper presents (i) the characteristics of ecological integrity, (ii) the spatial processes induced by anthropogenic stressors and (iii) an approach to develop a composite Regional Index of Ecological Integrity (RIEI). The prime objective is to establish a thought and a way to develop a composite index of ecological integrity at the regional level. Here, we demonstrate different compositional, structural and functional indicators/indices related to fragmentation, representativeness of protected area, ecosystem sensitivity, and landscape connectivity for the development of a Regional Index of Ecological Integrity (RIEI).  相似文献   
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