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51.
Adipose tissue‐derived mesenchymal stem cells (AD‐MSCs) have been shown to be capable of differentiating into multiple cell type and exert immunomodulatory effects. Since the selection of ideal stem cell is apparently crucial for the outcome of experimental stem cell therapies, therefore, in this study we compared AD‐MSCs conditioned media (CM) from BALB/c, C57BL/6, and DBA mouse strains. No significant difference was found in the morphology, cell surface markers, in vitro differentiation and proliferation potentials of AD‐MSCs isolated from C57BL/6, BALB/c, and DBA mice. The immunological assays showed some variation among the strains in the cytokines, nitric oxide (NO), and indoleamine 2,3‐dioxygenase (IDO) production and immunomodulatory effects on splenocytes functions. Our results indicated a suppression of splenocytes proliferation in the presence of AD‐MSC CM from the three inbred mouse strains. However, BALB/c CM exerted a higher suppression of splenocytes proliferation. AD‐MSCs isolated from C57BL/6 and BALB/c mice produced higher levels of TGF‐β than those from DBA mice. Furthermore, IL‐17 and IDO production was higher in AD‐MSCs isolated from BALB/c mice. Our results indicated an increased production of TGF‐β, IL‐4, IL‐10, NO, and IDO by splenocytes in response to CM from BALB/c AD‐MSCs. In conclusion, our results showed that the immunomodulatory properties of mouse AD‐MSCs is strain‐dependent and this variation should be considered during selection of appropriate stem cell source for in vivo experiments and stem cell therapy strategies. J. Cell. Biochem. 114: 955–965, 2013. © 2012 Wiley Periodicals, Inc.  相似文献   
52.
Five patients, four brothers and their paternal aunt, presented with a history of overt hyperthyroidism and goiter. Hyperthyroidism in this family was remarkable for its poor response to carbimazole (30–50 mg/d). The thyroid ultrasound showed a diffusely enlarged gland in all the affected members, and thyroid stimulating antibodies (TSAB) were negative. Screening for germline mutations in thyroid stimulating hormone (TSH) receptor (TSHR) gene was performed by direct sequencing of genomic DNA extracted from peripheral blood leukocytes of all family members. The sequence analysis of all TSHR gene exons and intron borders revealed two genomic variants. The first was a single nucleotide polymorphism (SNP) within exon seven (Asn187Asn), whereas the other was located in intron seven (IVS7+68T>G). All affected members, two asymptomatic brothers with sub-clinical hyperthyroidism, and their father were heterozygous for those two genomic variants. Anti-thyroid drug treatment for several months successfully relieved symptoms in one subject, whereas the remaining patients required total thyroidectomy to control their disease. This is the first Jordanian family with familial non-autoimmune hyperthyroidism, with mutations affecting the TSHR gene.  相似文献   
53.
Distinct metastasis is one of the main causes of breast cancer (BC)-related mortality and epithelial-mesenchymal transition (EMT) is a primary step in metastasis dissemination. On the other hand, doxorubicin (DOX) is an effective chemotherapeutic agent against BC; unfortunately, its clinical use is limited by dose-dependent side effects. Therefore, extensive efforts have been dedicated to suppressing metastasis of BC and also to overcome DOX side effects together with keeping its antitumor efficacy. Studies supported the role of oleuropein (OLEU) in reducing DOX-induced side effects besides its antitumor actions. In this study, the antimigratory effect of OLEU was assessed and real-time PCR (RT-PCR) was used to detect OLEU effect on the expression level of EMT markers, in MCF-7 cells. The cytotoxic effect of OLEU and DOX was assessed by MTT assay, whereas the ratio of apoptosis was investigated by flow cytometry. The results showed that migration ability of MCF-7 cells remarkably decreased in OLEU treated group and RT-PCR results showed that OLEU may exert its antimigratory action by suppressing EMT through downregulation of sirtuin1 (SIRT1). Also, the results indicated that both OLEU and DOX were cytotoxic to MCF-7 cells, whereas DOX-OLEU cotreatment led to additive cytotoxicity and apoptosis rate. This study provides evidence regarding the suppressive role of OLEU on MCF-7 cells migration ability through suppression of EMT, and for the first time, it was proposed that SIRT1 downregulation can be involved in the OLEU antimigratory effect. Also, the findings demonstrated that OLEU can reduce DOX-induced side effects by reducing its effective dose.  相似文献   
54.
Of the eight members of the herpes family of viruses, HSV1, HSV2, and varicella zoster are the most common and are mainly involved in cutaneous disorders. These viruses usually are not life-threatening, but in some cases they might cause serious infections to the eyes and the brain that can lead to blindness and possibly death. An effective drug (acyclovir and its derivatives) is available against these viruses. Therefore, early detection and identification of these viral infections is highly important for an effective treatment. Raman spectroscopy, which has been widely used in the past years in medicine and biology, was used as a powerful spectroscopic tool for the detection and identification of these viral infections in cell culture, due to its sensitivity, rapidity and reliability. Our results showed that it was possible to differentiate, with a 97% identification success rate, the uninfected Vero cells that served as a control, from the Vero cells that were infected with HSV-1, HSV-2, and VZV. For that, linear discriminant analysis (LDA) was performed on the Raman spectra after principal component analysis (PCA) with a leave one out (LOO) approach. Raman spectroscopy in tandem with PCA and LDA enable to differentiate among the different herpes viral infections of Vero cells in time span of few minutes with high accuracy rate. Understanding cell molecular changes due to herpes viral infections using Raman spectroscopy may help in early detection and effective treatment.  相似文献   
55.
The aim of this investigation was to evaluate the semen quality traits of purebred male rabbits and their crosses under subtropical Egyptian conditions. A full 3 x 3 diallel crossing was performed for producing the first generation progeny of New Zealand White (N), Flander (F) and Rex (R) breeds. The highest ejaculate volume (p< 0.05) and percentage of live sperms (p<0.01) with the lowest percentage of sperm cell morphological abnormalities (p<0.05) had been recorded in the NF bucks. Moreover, they possessed positive estimates of direct heterosis for ejaculate volume, mass motility (Mm), individual motility (Im) and sperm cell concentration (SCC). On the contrary, pH had negative estimates of direct heterosis in all crosses and their reciprocal. Semen pH was negatively correlated with SCC (r = -0.18), Mm (r = -0.13) and Im (r = -0.23). In conclusion, the superiority of crossbreeding was particularly obvious in the New Zealand White x Flander males, which cumulated heterosis and favorable maternal effects of the Flander dams.  相似文献   
56.
For decades, mesenchymal stem (MSCs) cells have been used for cardiovascular diseases as regenerative therapy. This review is an attempt to summarize the types of MSCs involved in myocardial infarction (MI) therapy, as well as its possible mechanisms effects, especially the paracrine one in MI focusing on the studies (human and animal) conducted within the last 10 years. Recently, reports showed that MSC therapy could have infarct‐limiting effects after MI in both experimental and clinical trials. In this context, various types of MSCs can help cardiac regeneration by either revitalizing the cardiac stem cells or revascularizing the arteries and veins of the heart. Furthermore, MSCs could produce paracrine growth factors that increase the survival of nearby cardiomyocytes, as well as increase angiogenesis through recruitment of stem cell from bone marrow or inducing vessel growth from existing capillaries. Recent research suggests that the paracrine effects of MSCs could be mediated by extracellular vesicles including exosomes. Exosomal microRNAs (miRNAs) released by MSCs are promising therapeutic hotspot target for MI. This could be attributed to the role of miRNA in cardiac biology, including cardiac regeneration, stem cell differentiation, apoptosis, neovascularization, cardiac contractility and cardiac remodeling. Furthermore, gene‐modified MSCs could be a recent promising therapy for MI to enhance the paracrine effects of MSCs, including better homing and effective cell targeted tissue regeneration. Although MSC therapy has achieved considerable attention and progress, there are critical challenges that remains to be overcome to achieve the most effective successful cell‐based therapy in MI.  相似文献   
57.
This study was conducted to determine the effects of dietary supplementation with Cr nicotinate and Cr chloride and their optimum inclusion rate on performance, carcass traits, meat oxidative stability, serum metabolites, hematological parameters, and liver chromium concentration in heat-stressed broilers. A total number of 420, 1-day-old male broiler chicks were randomly assigned to seven treatments with four replicates of 15 chicks. The dietary treatments consisted of the basal diet supplemented with 0 (control), 500, 1,000, and 1,500 μg/kg Cr in the form of Cr nicotinate and Cr chloride. Chicks were raised for 6 weeks in heat stress condition (33 ± 2°C). Supplements of organic and inorganic Cr particularly at 1,500 μg/kg incorporation increased feed consumption (P < 0.05) and body mass gain of broilers (P < 0.01). Cr supplementation increased carcass yield and decreased abdominal fat (P < 0.01). Supplementation of 1,500 μg/kg Cr nicotinate (P < 0.05) enhanced liver Cr concentration. Storage time increased lipid oxidation of meat (P < 0.01). Cr decreased lipid oxidation of breast and thigh muscles over 2 (P < 0.01) or 6 (P < 0.05) days of storage time. Birds fed 1,500 μg/kg Cr nicotinate, had lower concentration of serum glucose and triglyceride at 21 days (P < 0.05). Hematological parameters tested at 21 and 42 days, were not influenced. The results suggested that dietary Cr supplementation regardless of its source have a positive effect on productive, and carcass traits, also enhances oxidative stability of refrigerated meat in broilers reared under heat stress conditions.  相似文献   
58.
Summary This paper describes a new fully differentiated Type-II alveolar epithelial cell line designated T7, derived from transgenic H-2Kb-tsA58 mice, capable of being passaged as an immortalized cloned cell line in culture. H-2Kb-tsA58 mice harbor a temperature-sensitive (ts) mutant of the simian virus 40 (SV40) large tumor antigen (T antigen) under the control of the γ-interferon (INF)-inducible mouse major histocompatibility complex H-2Kb promoter. When cultured under permissive conditions (33°C and in the presence of γ-INF) cells isolated from H-2Kb-tsA58 mice express the large T antigen, which drives the cells to proliferate. However, upon withdrawal of the γ-INF and transfer of the cells to a higher temperature (39°C), T antigen expression is turned off, the cells stop proliferating and differentiate. The T7 cell line is a clonal cell line originally derived from a Type-II cell-rich fraction isolated from lungs of H-2Kb-tsA58 mice. The T7 cells form confluent monolayers, and have a polarized epithelial cell morphology with tight junctions and apical microvilli. In addition, the T7 cells have distinct cytoplasmic lamellar bodies, which become more numerous and pronounced when the cells are grown under nonpermissive conditions. The T7 cells synthesize and secrete phosphatidylcholine and the three surfactant proteins, SP-A, SP-B, and SP-C. The T7 cell line is unique in that it is the first non-tumor-derived Type-II cell line capable of synthesizing and secreting the major components of surfactant. Based on the criteria studied, the T7 cell line is phenotypically very similar to normal Type-II cells. The T7 cell line, therefore, should prove a valuable experimental system to advance the study of the cell biology/physiology of surfactant metabolism and secretion as well as serve as a model for other studies of Type-II cell physiology.  相似文献   
59.
A persistent challenge in the treatment of non‐small cell lung cancer (NSCLC) with EGFR is the emergence of drug‐resistant caused by somatic mutations. The EGFR L858R/T790 M double mutant (EGFRDM) was found to be the most alarming variant. Despite the development of a wide range of inhibitors, none of them could inhibit EGFRDM effectively. Recently, 11h and 45a , have been found to be potent inhibitors against EGFRDM through two distinctive mechanisms, non‐covalent and covalent binding, respectively. However, the structural and dynamic implications of the two modes of inhibitions remain unexplored. Herein, two molecular dynamics simulation protocols, coupled with free‐energy calculations, were applied to gain insight into the atomistic nature of each binding mode. The comparative analysis confirmed that there is a significant difference in the binding free energy between 11h and 45a (ΔΔGbind=?21.17 kcal/mol). The main binding force that governs the binding of both inhibitors is vdW, with a higher contribution for 45a . Two residues ARG841 and THR854 were found to have curtailed role in the binding of 45a to EGFRDM by stabilizing its flexible alcohol chain. The 45a binding to EGFRDM induces structural rearrangement in the active site to allow easier accessibility of 45a to target residue CYS797. The findings of this work can substantially shed light on new strategies for developing novel classes of covalent and non‐covalent inhibitors with increased specificity and potency.  相似文献   
60.
Prevention of viral-induced respiratory disease begins with an understanding of the factors that increase or decrease susceptibility to viral infection. The primary receptor for most adenoviruses is the coxsackievirus and adenovirus receptor (CAR), a cell-cell adhesion protein normally localized at the basolateral surface of polarized epithelia and involved in neutrophil transepithelial migration. Recently, an alternate isoform of CAR, CAREx8, has been identified at the apical surface of polarized airway epithelia and is implicated in viral infection from the apical surface. We hypothesized that the endogenous role of CAREx8 may be to facilitate host innate immunity. We show that IL-8, a proinflammatory cytokine and a neutrophil chemoattractant, stimulates the protein expression and apical localization of CAREx8 via activation of AKT/S6K and inhibition of GSK3β. Apical CAREx8 tethers infiltrating neutrophils at the apical surface of a polarized epithelium. Moreover, neutrophils present on the apical-epithelial surface enhance adenovirus entry into the epithelium. These findings suggest that adenovirus evolved to co-opt an innate immune response pathway that stimulates the expression of its primary receptor, apical CAREx8, to allow the initial infection the intact epithelium. In addition, CAREx8 is a new target for the development of novel therapeutics for both respiratory inflammatory disease and adenoviral infection.  相似文献   
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