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801.
Human induced pluripotent stem cells (hiPSCs) are a type of pluripotent stem cells artificially derived from an adult somatic cell (typically human fibroblast) by forced expression of specific genes. In recent years, different feeders like inactivated mouse embryonic fibroblasts (MEFs), human dermal fibroblasts (HDFs), and feeder free system have commonly been used for supporting the culture of stem cells in undifferentiated state. In the present work, the culture of hiPSCs and their characterizations on BD Matrigel (feeder-and serum-free system), MEF and HDF feeders using cell culture methods and molecular techniques were evaluated and compared. The isolated HDFs from foreskin samples were reprogrammed to hiPSCs using gene delivery system. Then, the pluripotency ability of hiPSCs cultured on each layer was determined by teratoma formation and immunohistochemical staining. After EBs generation the expression level of three germ layers genes were evaluated by Q-real-time PCR. Also, the cytogenetic stability of hiPSCs cultured on each condition was analyzed by karyotyping and comet assay. Then, the presence of pluripotency antigens were confirmed by Immunocytochemistry (ICC) test and alkaline phosphatase staining. This study were showed culturing of hiPSCs on BD Matrigel, MEF and HDF feeders had normal morphology and could maintain in undifferentiated state for prolonged expansion. The hiPSCs cultured in each system had normal karyotype without any chromosomal abnormalities and the DNA lesions were not observed by comet assay. Moreover, up-regulation in three germ layers genes in cultured hiPSCs on each layer (same to ESCs) compare to normal HDFs were observed (p < 0.05). The findings of the present work were showed in stem cells culturing especially hiPSCs both MEF and HDF feeders as well as feeder free system like Matrigel are proper despite benefits and disadvantages. Although, MEFs is suitable for supporting of stem cell culturing but it can animal pathogens transferring and inducing immune response. Furthermore, HDFs have homologous source with hiPSCs and can be used as feeder instead of MEF but in therapeutic approaches the cells contamination is a problem. So, this study were suggested feeder free culturing of hiPSCs on Matrigel in supplemented media (without using MEF conditioned medium) resolves these problems and could prepare easy applications of hiPSCs in therapeutic approaches of regenerative medicine such as stem-cell therapy and somatic cell nuclear in further researches.  相似文献   
802.

Background:

Neisseria meningitidis, a life-threatening human pathogen with the potential to cause large epidemics, can be isolated from the nasopharynx of 5–15% of adults. The aim of the current study was to evaluate biophysical and biochemical properties and immunological aspects of chimeric acyl-carrier protein-macrophage infectivity potentiator protein-type IV pilus biogenesis protein antigen (ACP-MIP-PilQ) from N. meningitidis serogroup B strain.

Methods:

Biochemical properties and multiple alignments were predicted by appropriate web servers. Secondary molecular structures were predicted based on Chou and Fasman, Garnier-Osguthorpe-Robson, and Neural Network methods. Tertiary modeling elucidated conformational properties of the chimeric protein. Proteasome cleavage and transporter associated with antigen processing (TAP) binding sites, and T- and B-cell antigenic epitopes, were predicted using bioinformatic web servers.

Results:

Based on our in silico and immunoinformatics analyses, the ACP-MIP-PilQ protein (AMP) can induce high-level cross-strain bactericidal activity. In addition, several immune proteasomal cleavage sites were detected. The 22 epitopes associated with MHC class I and class II (DR) alleles were confirmed in the AMP. Thirty linear B-cell epitopes as antigenic regions were predicted from the full-length protein.

Conclusion:

All predicted properties of the AMP indicate it could be a good candidate for further immunological in vitro and in vivo studies.Key Words: Chimeric protein, In silico, Neisseria meningitides, serogroup B, Vaccine  相似文献   
803.
Journal of Plant Growth Regulation - This study was conducted to explore the capability of seed priming with the cold plasma and multi-walled carbon nanotubes (MWCNT), in order to improve growth...  相似文献   
804.
Molecular Biology Reports - Timely and successful resolution of acute inflammation plays a crucial role in preventing the development of chronic airway inflammation in allergic rhinitis (AR). This...  相似文献   
805.
International Journal of Peptide Research and Therapeutics - Irisin is a soluble and exercise-induced myokine and/or adipokine hormone; generated by FNDC5 (a gene precursor) and also, it can...  相似文献   
806.
International Journal of Peptide Research and Therapeutics - One of the main challenges in oral disease is prevention of bacterial infections considering antibiotic resistance as a result of...  相似文献   
807.
Gastric cancer (GC) is one of the prevalent human malignancies and the third most common cause of cancer‐related death worldwide. The doxorubicin hydrochloride is one of the important chemotherapeutic anticancer agents, with a limited therapeutic efficacy for treatment of GC. Therefore, taking advantage of synergistic effects by strategies like combination therapy seems appropriate and promising in treatment of GC. The aim of this study was to investigate a novel method to enhance the therapeutic efficacy of doxorubicin (as a chemotherapeutic agent) by co‐administration of curcumin (as a bioactive herbal compound) in GC treatment. In the present study, the effects of curcumin, doxorubicin, and their combinations (Dox‐Cur) were evaluated on the viability, morphological features, tumor spheroid formation, migration, invasion, and apoptosis of gastric adenocarcinoma cell line (AGS). Moreover, expression levels of BAX, BCL‐2, and CASP9 genes were assessed among AGS cells treated with curcumin, doxorubicin, and Dox‐Cur. The obtained results showed that all of curcumin, doxorubicin, and Dox‐Cur treatments significantly decreased the viability, tumor spheroid formation, migration, and invasion in the GC model cells. Furthermore, apoptosis rates in AGS cells were increased in a concentration‐ and time‐dependent manner in all of the treatment groups. Moreover, the anticancer activity of the Dox‐Cur combination was significantly more than curcumin and doxorubicin treatments alone. According to the results, Dox‐Cur combination therapy exerts more profound apoptotic and anticancer effects on the AGS cell line than curcumin or doxorubicin monotherapy.  相似文献   
808.
In the present study, beneficial effect of S‐allyl cysteine (SAC) was evaluated in the lipopolysaccharide/d ‐galactosamine (LPS/d ‐Gal) model of acute liver injury (ALI). To mimic ALI, LPS and d ‐Gal (50 μg/kg and 400 mg/kg, respectively) were intraperitoneally administered and animals received SAC per os (25 or 100 mg/kg/d) for 3 days till 1 hour before LPS/d ‐Gal injection. Pretreatment of LPS/d ‐Gal group with SAC‐lowered activities of alkaline phosphatase, alanine aminotransferase, and aspartate aminotransferase and partially reversed inappropriate alterations of hepatic oxidative stress‐ and inflammation‐related biomarkers including liver reactive oxygen species, malondialdehyde, and hepatic activity of the defensive enzyme superoxide dismutase, ferric reducing antioxidant power (FRAP), toll‐like receptor‐4 (TLR4), cyclooxygenase 2, NLR family pyrin domain containing 3 (NLRP3), caspase 1, nuclear factor κB (NF‐κB), interleukin 1β (IL‐1β), IL‐6, tumor necrosis factor‐α, and myeloperoxidase activity. Additionally, SAC was capable to ameliorate apoptotic biomarkers including caspase 3 and DNA fragmentation. In summary, SAC can protect liver against LPS/d ‐Gal by attenuation of neutrophil infiltration, oxidative stress, inflammation, apoptosis, and pyroptosis which is partly linked to its suppression of TLR4/NF‐κB/NLRP3 signaling.  相似文献   
809.
810.
Rahmani  Amir Masoud  Babaei  Zahra  Souri  Alireza 《Cluster computing》2021,24(2):1347-1360
Cluster Computing - Internet of Things (IoT) is enhancing the intelligence of the societies through a rapid transition to a smarter, automatic, responsive world due to the dramatic increase in the...  相似文献   
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