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51.
Objectives
Donor specific antibodies (DSA) and a positive cross‐match are contraindications for kidney transplantation. Trials of allograft transplantation across the HLA barrier have employed desensitization strategies, including the use of plasmapheresis, intravenous immunoglobulins, anti‐B‐cell monoclonal antibodies and splenectomy, associated with high‐intensity immunosuppressive regimens. Our case 1 report suffered from repeatedly positive lymphocyte cross match after 1st renal transplantation. Graft nephrectomy could not correct the state of sensitization. Splenectomy was done in a trial to get rid of the antibody producing clone. Furthermore plasmapheresis with low dose IVIG could not as well revert the state of sensitization for the patient.Material and methods
About 50 millions donor specific MSCs were injected to the patient.Results
MSCs transfusion proved to be the only procedure which could achieve successful desensitization before performing the second transplantation owing to their immunosuppressive properties.Conclusion
This case indicates that DS‐MSCs is a potential option for anti‐HLA desensitization. In cases 2 and 3 IV DS‐MSCs transfusion was selected from the start as a successful line of treatment for pre renal transplantation desensitization to save other unnecessary lines of treatment that were tried in case 1.52.
Zahra?Asadi?Kalmeh Negar?AzarpiraEmail author Mahnaz?Mosallaei Hamid?Hosseini Zahra?Malekpour 《Molecular biology reports》2013,40(7):4613-4618
Retinopathy of prematurity (ROP) is a multifactorial disease, that cause visual impairment in premature children. The exact pathogenesis and etiology of ROP is unknown and genetic susceptibility is considered as risk factor. Vascular endothelial growth factor (VEGF) plays a major role in retinal neovascularization and subsequently retinal detachment. VEGF polymorphism is associated with proliferative ROP in some studies. We examined the possible association of the VEGF gene polymorphisms with ROP in preterm infants in south of Iran. A total of 111 preterm infants were examined by ophthalmologist and after that were genotyped. Genotyping of the VEGF +405 (rs2010963) and VEGF +936 (rs3025039) was done by the polymerase chain reaction and restriction fragment length polymorphism methods. The frequency of VEGF alleles, genotypes and haplotype distribution were compared between groups. The patients were divided in three groups: 66 to the normal group (normal fundoscopy), and 45 to the ROP group; 30 infants were not treated with Lasertherapy (Regressive group) and 15 treated with Lasertherapy. The frequency of VEGF +405 and VEGF +936 G/C genotypes as well as allele frequencies was not different between groups. No significant difference was found between ROP with treatment and ROP without lasertherapy. Our report indicate that there is no association between the carrier states of gene polymorphisms VEGF +405, VEGF +936 and progression or spontaneous regression of ROP in preterm infants in Iranian population. However, it should be considered that angiogenesis is a complex process and genetic factors in addition to environmental factors are contributed in this pathway. 相似文献
53.
Umesh C. S. Yadav Amarjit S. Naura Leopoldo Aguilera-Aguirre Istvan Boldogh Hamid A. Boulares William J. Calhoun Kota V. Ramana Satish K. Srivastava 《PloS one》2013,8(2)
Background
Long-term and unresolved airway inflammation and airway remodeling, characteristic features of chronic asthma, if not treated could lead to permanent structural changes in the airways. Aldose reductase (AR), an aldo-sugar and lipid aldehyde metabolizing enzyme, mediates allergen-induced airway inflammation in mice, but its role in the airway remodeling is not known. In the present study, we have examined the role of AR on airway remodeling using ovalbumin (OVA)-induced chronic asthma mouse model and cultured human primary airway epithelial cells (SAECs) and mouse lung fibroblasts (mLFs).Methods
Airway remodeling in chronic asthma model was established in mice sensitized and challenged twice a week with OVA for 6 weeks. AR inhibitor, fidarestat, was administered orally in drinking water after first challenge. Inflammatory cells infiltration in the lungs and goblet cell metaplasia, airway thickening, collagen deposition and airway hyper-responsiveness (AHR) in response to increasing doses of methacholine were assessed. The TGFβ1-induced epithelial-mesenchymal transition (EMT) in SAECs and changes in mLFs were examined to investigate AR-mediated molecular mechanism(s) of airway remodeling.Results
In the OVA-exposed mice for 6 wks inflammatory cells infiltration, levels of inflammatory cytokines and chemokines, goblet cell metaplasia, collagen deposition and AHR were significantly decreased by treatment with AR inhibitor, fidarestat. Further, inhibition of AR prevented TGFβ1-induced altered expression of E-cadherin, Vimentin, Occludin, and MMP-2 in SAECs, and alpha-smooth muscle actin and fibronectin in mLFs. Further, in SAECs, AR inhibition prevented TGFβ1- induced activation of PI3K/AKT/GSK3β pathway but not the phosphorylation of Smad2/3.Conclusion
Our results demonstrate that allergen-induced airway remodeling is mediated by AR and its inhibition blocks the progression of remodeling via inhibiting TGFβ1-induced Smad-independent and PI3K/AKT/GSK3β-dependent pathway. 相似文献54.
N-(2-Hydroxypropyl)methacrylamide (HPMA) copolymers (pHPMA) containing 4-nitrophenyl ester (ONp) or thiazolidine-2-thione (TT) reactive groups in side chains and telechelic/semitelechelic pHPMA with TT groups were designed as highly hydrophilic biocompatible polymers suitable for chemical coating of polyelectrolyte-based DNA-containing nanoparticles bearing amino groups on the surface. The course of the coating reaction carried out in aqueous solution was evaluated on model self-assembling polyelectrolyte DNA/poly(L-lysine) (DNA/PLL) complexes either by monitoring the amount of residual polymer reactive groups by UV spectroscopy or by monitoring changes in the weight-average molecular weight and hydrodynamic size of the complexes using light scattering methods. Physicochemical stability of the coated complexes in buffered saline solution was also investigated. Contrary to uncoated particles, the coated complexes showed remarkable stability to aggregate in 0.15 M NaCl. Coating with pHPMA had practically no effect on the size distribution of the most stable complexes prepared by complexation of DNA with high-molecular-weight PLL (M(w) = 134 000) as shown by dynamic light scattering. The coating reaction was faster and more efficient with multivalent HPMA copolymers containing TT reactive groups than that with HPMA copolymers containing ONp groups. 相似文献
55.
The tissues of multicellular organisms are made of differentiated cells arranged in organized patterns. This organization emerges during development from the coupling of dynamic intra- and intercellular regulatory networks. This work applies the methods of information theory to understand how regulatory network structure both within and between cells relates to the complexity of spatial patterns that emerge as a consequence of network operation. A computational study was performed in which undifferentiated cells were arranged in a two dimensional lattice, with gene expression in each cell regulated by identical intracellular randomly generated Boolean networks. Cell–cell contact signalling between embryonic cells is modeled as coupling among intracellular networks so that gene expression in one cell can influence the expression of genes in adjacent cells. In this system, the initially identical cells differentiate and form patterns of different cell types. The complexity of network structure, temporal dynamics and spatial organization is quantified through the Kolmogorov-based measures of normalized compression distance and set complexity. Results over sets of random networks that operate in the ordered, critical and chaotic domains demonstrate that: (1) ordered and critical networks tend to create the most information-rich patterns; (2) signalling configurations in which cell-to-cell communication is non-directional mostly produce simple patterns irrespective of the internal network domain; and (3) directional signalling configurations, similar to those that function in planar cell polarity, produce the most complex patterns, but only when the intracellular networks function in non-chaotic domains. 相似文献
56.
The T cell-specific CXC chemokines IP-10, Mig, and I-TAC are expressed by activated human bronchial epithelial cells 总被引:32,自引:0,他引:32
Sauty A Dziejman M Taha RA Iarossi AS Neote K Garcia-Zepeda EA Hamid Q Luster AD 《Journal of immunology (Baltimore, Md. : 1950)》1999,162(6):3549-3558
Recruitment of activated T cells to mucosal surfaces, such as the airway epithelium, is important in host defense and for the development of inflammatory diseases at these sites. We therefore asked whether the CXC chemokines IFN-induced protein of 10 kDa (IP-10), monokine induced by IFN-gamma (Mig), and IFN-inducible T-cell alpha-chemoattractant (I-TAC), which specifically chemoattract activated T cells by signaling through the chemokine receptor CXCR3, were inducible in respiratory epithelial cells. The effects of proinflammatory cytokines, including IFN-gamma (Th1-type cytokine), Th2-type cytokines (IL-4, IL-10, and IL-13), and dexamethasone were studied in normal human bronchial epithelial cells (NHBEC) and in two human respiratory epithelial cell lines, A549 and BEAS-2B. We found that IFN-gamma, but not TNF-alpha or IL-1 beta, strongly induced IP-10, Mig, and I-TAC mRNA accumulation mainly in NHBEC and that TNF-alpha and IL-1 beta synergized with IFN-gamma induction in all three cell types. High levels of IP-10 protein (> 800 ng/ml) were detected in supernatants of IFN-gamma/TNF-alpha-stimulated NHBEC. Neither dexamethasone nor Th2 cytokines modulated IP-10, Mig, or I-TAC expression. Since IFN-gamma is up-regulated in tuberculosis (TB), using in situ hybridization we studied the expression of IP-10 in the airways of TB patients and found that IP-10 mRNA was expressed in the bronchial epithelium. In addition, IP-10-positive cells obtained by bronchoalveolar lavage were significantly increased in TB patients compared with normal controls. These results show that activated bronchial epithelium is an important source of IP-10, Mig, and I-TAC, which may, in pulmonary diseases such as TB (in which IFN-gamma is highly expressed) play an important role in the recruitment of activated T cells. 相似文献
57.
58.
Biosurfactant production by Mucor circinelloides: Environmental applications and surface‐active properties 下载免费PDF全文
Biosurfactants are structurally a diverse group of surface‐active molecules widely used for various purposes in industry. In this study, among 120 fungal isolates, M‐06 was selected as a superior biosurfactant producer, based on different standard methods, and was identified as Mucor circinelloides on the basis of its nucleotide sequence of the internal transcribed spacer (ITS) gene. M. circinelloides reduced the surface tension to 26 mN/m and its EI24 index was determined to be 66.6%. The produced biosurfactant exhibited a high degree of stability at a high temperature (121°C), salinity (40 g/L), and acidic pH (2–8). The fermentation broth's ability to recover oil from contaminated sand was 2 and 1.8 times higher than those of water and Tween 80, respectively. The ability of biosurfactant to emulsify crude oil in the sea and fresh water was 64.9 and 48% respectively. This strain could remove 87.6% of crude oil in the Minimal Salt Medium (MSM) crude oil as the sole carbon source. The results from a primary chemical characterization of crude biosurfactant suggest that it is of a glycolipid nature. The strain and its biosurfactant could be used as a potent candidate in bioremediation of oil‐contaminated water, soil, and for oil recovery processes. 相似文献
59.
60.
Abdul Hamid 《Plant and Soil》1972,36(1-3):709-711