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The aim of current study is to tailor chitosan derivate which is water-soluble while presents original biological features of chitosan. For this purpose, the 6-O chitosan sulfate (CS) with naked amine groups was synthesized via regioselective modification of chitosan (C) during which both crosslinking capacity and antibacterial properties of the C were remained intact. This was achieved by sulfation the C under controlled acidic conditions using chlorosulfonic acid/sulfuric acid mixture. Subsequently, a chemically crosslinked hydrogel of the CS was used as a wound dressing substrate. The modified sulfate groups retained the biocompatibility of C and showed antibacterial effects against gram-positive and gram-negative bacteria. In addition, the presence of sulfate groups in the CS chemical structure improved its anticoagulant activity compared to the unmodified C. Both in vitro and in vivo enzyme-linked immunosorbent assay (ELISA) measurements showed that CS had a higher potential to bind and scavenger anti-inflammatory cytokines, including IL-6 and transforming growth factor-ß (TGF-ß), both of which play critical roles in the early stage of the wound healing process. After treatment of full-thickness wounds with CS hydrogels, the macrophage cells (c.a. 6 × 104 cells) expressed significantly more M2 phenotype markers compared to the C group (4.2 × 104 cells). Furthermore, the CS hydrogel induced better re-epithelialization and vascularization of full-thickness wounds in mice compared to the C hydrogel during 30 days.
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Quitosana , Animais , Antibacterianos/farmacologia , Bandagens/microbiologia , Quitosana/farmacologia , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Hidrogéis/farmacologia , Camundongos , SulfatosRESUMO
In this article which was published in Cell J, Vol 17, No 2, Summer 2015, on pages 211-220, the authors found that Figures 3 and 4 had some errors that accidentally happened during organizing figures as well as because of mislabeling of some images and saving them in an incorrect folder. The following figures are corrected. The authors would like to apologies for any inconvenience caused.
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OBJECTIVE: This study was performed to evaluate the correlation of hyaluronic acid binding assay (HBA) with conventional semen parameters, lipid peroxidation (LPO), intracellular reactive oxygen species (ROS), DNA fragmentation (DF), DNA maturity and mitochondrial membrane potential (MMP) level in human spermatozoa. METHODS: The semen samples were obtained from 98 patients. The seminal plasma was separated for the study of LPO, and the pellet was employed for evaluation of intracellular ROS, DF, nuclear maturity (sperm chromatin structure assay) and MMP through flowcytometry. RESULTS: The correlation and strength of HBA with respect to the studied parameters were estimated by the Pearson coefficient and multiple liner regression tests. While HBA indicated a positive correlation with progressive motility (ß-coefficients = 0.449, p < 0.05) and normal morphology (ß-coefficients = 2.722, p < 0.01), it had only negative relationship with DNA integrity (high DNA stain ability; ß-coefficients = -0.517, p < 0.05). HBA also did not show any important correlation with other conventional and intracellular sperm parameters. CONCLUSIONS: The HBA is sensitive to morphological integrity, high progressive motility and nuclear maturation. Nonetheless, HBA is not a reliable test for prediction of sperm intracellular ROS, DF and MMP risks and healthy spermatozoa selection.
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Núcleo Celular/ultraestrutura , Ácido Hialurônico/metabolismo , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Separação Celular/métodos , Cromatina/ultraestrutura , Fragmentação do DNA , Humanos , Peroxidação de Lipídeos , Masculino , Potencial da Membrana Mitocondrial , Espécies Reativas de Oxigênio/análise , Contagem de Espermatozoides , Espermatozoides/química , Espermatozoides/ultraestruturaRESUMO
OBJECTIVE: Genetic modification of human embryonic stem cells (hESCs) is critical for their extensive use as a fundamental tool for cell therapy and basic research. Despite the fact that various methods such as lipofection and electroporation have been applied to transfer the gene of interest (GOI) into the target cell line, however, there are few re- ports that compare all parameters, which influence transfection efficiency. In this study, we examine all parameters that affect the efficiency of electroporation and lipofection for transient and long-term gene expression in three different cell lines to introduce the best method and determinant factor. MATERIALS AND METHODS: In this experimental study, both electroporation and lipofection approaches were employed for genetic modification. pCAG-EGFP was applied for tran- sient expression of green fluorescent protein in two genetically different hESC lines, Roy- an H5 (XX) and Royan H6 (XY), as well as human foreskin fibroblasts (hFF). For long-term EGFP expression VASA and OLIG2 promoters (germ cell and motoneuron specific genes, respectively), were isolated and subsequently cloned into a pBluMAR5 plasmid backbone to drive EGFP expression. Flow cytometry analysis was performed two days after trans- fection to determine transient expression efficiency. Differentiation of drug resistant hESC colonies toward primordial germ cells (PGCs) was conducted to confirm stable integration of the transgene. RESULTS: Transient and stable expression suggested a variable potential for different cell lines against transfection. Analysis of parameters that influenced gene transformation ef- ficiency revealed that the vector concentrations from 20-60 µg and the density of the sub- jected cells (5×10(5)and 1×10(6)cells) were not as effective as the genetic background and voltage rate. The present data indicated that in contrast to the circular form, the linearized vector generated more distinctive drug resistant colonies. CONCLUSION: Electroporation was an efficient tool for genetic engineering of hESCs compared to the chemical method. The genetic background of the subjected cell line for transfection seemed to be a fundamental factor in each gene delivery method. For each cell line, optimum voltage rate should be calculated as it has been shown to play a crucial role in cell death and rate of gene delivery.
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The human Y chromosome has an inevitable role in male fertility because it contains many genes critical for spermatogenesis and the development of the male gonads. Any genetic variation or epigenetic modification affecting the expression pattern of Y chromosome genes may thus lead to male infertility. In this study, we performed isoform-level gene expression profiling of Y chromosome genes within the azoospermia factor (AZF) regions, their X chromosome counterparts, and few autosomal paralogues in testicular biopsies of 12 men with preserved spermatogenesis and 68 men with nonobstructive azoospermia (NOA) (40 Sertoli-cell-only syndrome (SCOS) and 28 premiotic maturation arrest (MA)). This was undertaken using quantitative real-time PCR (qPCR) at the transcript level and Western blotting (WB) and immunohistochemistry (IHC) at the protein level. We profiled the expression of 41 alternative transcripts encoded by 14 AZFa, AZFb, and AZFc region genes (USP9Y, DDX3Y, XKRY, HSFY1, CYORF15A, CYORF15B, KDM5D, EIF1AY, RPS4Y2, RBMY1A1, PRY, BPY2, DAZ1, and CDY1) as well as their X chromosome homologue transcripts and a few autosomal homologues. Of the 41 transcripts, 18 were significantly down-regulated in men with NOA when compared with those of men with complete spermatogenesis. In contrast, the expression of five transcripts increased significantly in NOA patients. Furthermore, to confirm the qPCR results at the protein level, we performed immunoblotting and IHC experiments (based on 24 commercial and homemade antibodies) that detected 10 AZF-encoded proteins. In addition, their localization in testis cell types and organelles was determined. Interestingly, the two missing proteins, XKRY and CYORF15A, were detected for the first time. Finally, we focused on the expression patterns of the significantly altered genes in 12 MA patients with successful sperm retrieval compared to those of 12 MA patients with failed sperm retrieval to predict the success of sperm retrieval in azoospermic men. We showed that HSFY1-1, HSFY1-3, BPY2-1, KDM5C2, RBMX2, and DAZL1 transcripts could be used as potential molecular markers to predict the presence of spermatozoa in MA patients. In this study, we have identified isoform level signature that can be used to discriminate effectively between MA, SCOS, and normal testicular tissues and suggests the possibility of diagnosing the presence of mature sperm cell in azoospermic men to prevent additional testicular sperm extraction (TESE) surgery.
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Azoospermia/genética , Cromossomos Humanos X , Cromossomos Humanos Y , Perfilação da Expressão Gênica , Testículo/patologia , Adulto , Azoospermia/patologia , Humanos , Masculino , Pessoa de Meia-IdadeRESUMO
OBJECTIVE: Pancreatic stroma plays an important role in the induction of pancreatic cells by the use of close range signaling. In this respect, we presume that pancreatic mesenchymal cells (PMCs) as a fundamental factor of the stromal niche may have an effective role in differentiation of umbilical cord blood cluster of differentiation 133(+) (UCB-CD133(+)) cells into newly-formed ß-cells in vitro. MATERIALS AND METHODS: This study is an experimental research. The UCB-CD133(+)cells were purified by magnetic activated cell sorting (MACS) and differentiated into insulin producing cells (IPCs) in co-culture, both directly and indirectly with rat PMCs. Immunocytochemistry and enzyme linked immune sorbent assay (ELISA) were used to determine expression and production of insulin and C-peptide at the protein level. RESULTS: Our results demonstrated that UCB-CD133(+)differentiated into IPCs. Cells in islet-like clusters with (out) co-cultured with rat pancreatic stromal cells produced insulin and C-peptide and released them into the culture medium at the end of the induction protocol. However they did not respond well to glucose challenges. CONCLUSION: Rat PMCs possibly affect differentiation of UCB-CD133(+)cells into IPCs by increasing the number of immature ß-cells.
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Flow cytometers designed to analyze large particles are enabling new applications in biology. Data analysis is a critical component of the process FCM. In this article we compare features of four free software packages including WinMDI, Cyflogic, Flowing software, and Cytobank.