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41.
The generation of human induced pluripotent stem cells (hiPSCs) from an individual patient provides a unique tool for disease modeling, drug discovery, and cell replacement therapies. Patient-specific pluripotent stem cells can be expanded in vitro and are thus suitable for genetic manipulations. To date, several genetic liver disorders have been modeled using patient-specific hiPSCs. Here, we present the generation of corrected hepatocyte-like cells (HLCs) from hiPSCs of a familial hypercholesterolemia (FH) patient with a homozygous mutation in the low-density lipoprotein receptor (LDLR) gene. We generated hiPSCs from a patient with FH with the mutated gene encoding a truncated non-functional receptor. In order to deliver normal LDLR to the defective cells, we used a plasmid vector carrying the normal receptor ORF to genetically transform the hiPSCs. The transformed cells were expanded and directed toward HLCs. Undifferentiated defective hiPSCs and HLCs differentiated from the defective hiPSCs did not have the ability to uptake labeled low-density lipoprotein (LDL) particles. The differentiated transformed hiPSCs showed LDL-uptake ability and the correction of disease phenotype as well as expressions of hepatocyte-specific markers. The functionality of differentiated cells was also confirmed by indo-cyanine green (ICG) uptake assay, PAS staining, inducible cyp450 activity, and oil red staining. These data suggest that hiPSC technology can be used for generation of disease-corrected, patient-specific HLCs with potential value for disease modeling and drug discovery as well as cell therapy applications in future.  相似文献   
42.

Background

Alveolar echinococcosis is a zoonotic disease caused by the metacestode of Echinococcus multilocularis. Many species of small mammals, including arvicolid rodents or Ochotona spp., are natural intermediate hosts of the cestode. The main aim of this study was to identify natural intermediate hosts of E. multilocularis in Chenaran County, Razavi Khorasan Province, northeastern Iran, where the prevalence of infected wild and domestic carnivores is high.

Methodology/Principal Findings

A program of trapping was carried out in five villages in which this cestode was reported in carnivores. The livers of 85 small mammals were investigated for the presence of E. multilocularis infection using multiplex PCR of mitochondrial genes. Infections were identified in 30 specimens: 23 Microtus transcaspicus, three Ochotona rufescens, two Mus musculus, one Crocidura gmelini, and one Apodemus witherbyi.

Conclusions/Significance

A range of small mammals therefore act as natural intermediate hosts for the transmission of E. multilocularis in Chenaran County, and the prevalence suggested that E. multilocularis infection is endemic in this region. The existence of the life cycle of this potentially lethal cestode in the vicinity of human habitats provides a significant risk of human infection.  相似文献   
43.

Background

Echinococcus multilocularis is the source of alveolar echinococcosis, a potentially fatal zoonotic disease. This investigation assessed the presence of E. multilocularis infection in definitive hosts in the Chenaran region of Razavi Khorasan Province, northeastern Iran.

Methodology/Principal Findings

Fecal samples from 77 domestic and stray dogs and 14 wild carnivores were examined using the flotation/sieving method followed by multiplex PCR of mitochondrial genes. The intestinal scraping technique (IST) and the sedimentation and counting technique (SCT) revealed adult Echinococcus in the intestines of five of 10 jackals and of the single wolf examined. Three jackals were infected only with E. multilocularis but two, and the wolf, were infected with both E. multilocularis and E. granulosus. Multiplex PCR revealed E. multilocularis, E. granulosus, and Taenia spp. in 19, 24, and 28 fecal samples, respectively. Echinococcus multilocularis infection was detected in the feces of all wild carnivores sampled including nine jackals, three foxes, one wolf, one hyena, and five dogs (6.5%). Echinococcus granulosus was found in the fecal samples of 16.9% of dogs, 66.7% of jackals, and all of the foxes, the wolf, and the hyena. The feces of 16 (21.8%) dogs, 7 of 9 (77.8%) jackals, and all three foxes, one wolf and one hyena were infected with Taenia spp.

Conclusions/Significance

The prevalence of E. multilocularis in wild carnivores of rural areas of the Chenaran region is high, indicating that the life cycle is being maintained in northeastern Iran with the red fox, jackal, wolf, hyena, and dog as definitive hosts.  相似文献   
44.
New amphiphilic chitosan derivatives of all trans retinoic acid-chitosan (RA-chitosan) with different molar feeding ratios of all trans retinoic acid (ATRA) were synthesized. The degree of ATRA substitution ranged from 8.72% to 18.78%. The RA-chitosan formed micelles with an average size of 142.14-208.4 nm, and zeta potential of +27.25 to 34.48 mV. The critical association concentration (CAC) was found to range from 1.3 × 10−2 to 2.13 × 10−2 mg ml−1. Upon evaluation, the RA-chitosan shows no significant cytotoxicity on Hela and HepG2 cells. Analysis of micelles loaded with ATRA revealed that the size of micelles decreased by increasing loaded drug content while zeta potential did not change. ATRA was released slowly over 3-day period, and drug content had no effect on the release rate. These phenomena make RA-chitosan micelles as a candidate for drug carrier.  相似文献   
45.
The Wnt pathway is the most important cascade in the nervous system; evidence has indicated that deregulation of the Wnt pathway induced pathogenic hallmarks of neurodegenerative diseases. Glycogen synthase kinase-3β (GSK-3β) as the main member of the Wnt pathway increases tau inclusions, the main marker in the neurodegenerative diseases. Phosphorylated tau is observed in the pre-tangle of the neurons in the early stage of neurodegenerative diseases. The researchers always try to improve pharmacological approaches of new therapeutic strategies to the treatment of neurodegenerative diseases that are required to represent a significant entry point by understanding the theoretical interactions of the molecular pathways. In this review, we have discussed the recent knowledge about the canonical and non-canonical Wnt signalling pathway, GSK-3β, Wnt/β-catenin antagonists, tau phosphorylation, and their important roles in the neurodegenerative diseases.  相似文献   
46.
The phagocytic activity of neuroglial cells in adult feline degenerating optic nerve was investigated by immunocytochemistry at both light and electron microscopy levels. Degeneration was initiated by unilateral eye enucleation and the segment distal to the transection showing true Wallerian degeneration was examined. Following enucleation, twelve adult domestic cats were examined over a period of seven to 215 days. All cases showed slow clearance of myelin debris and absence of proliferating monocytes throughout the post-enucleation period. All phagocytic cells present were neuroglial cells, and many of these cells expressed oligodendroglial antigens. These findings demonstrate the persistence of an active population of oligodendrocytes that might play an additional functional role during Wallerian degeneration of feline optic nerve.  相似文献   
47.
Gastric cancer is one of the major causes of death due to cancer in the world. It is a multi-factorial disease with epigenetic factors being also involved in its development. FAT4 is a tumor suppressor gene exerting an important role in cell adhesion. This study aimed at analyzing FAT4 expression and promoter methylation in gastric cancer. FAT4 expression was studied in 30 tumoral tissues and their non-tumoral counterparts using Taqman real time PCR method. Promoter methylation was assessed using bisulfite conversion method followed by sequencing. Tumor tissues showed reduced FAT4 expression (P = 0.04). FAT4 downregulation was associated with tumor grade, with higher repression at advanced grades. Significant increase of promoter methylation was observed in tumoral tissues. Reduced expression of FAT4 and increased methylation of its promoter may be one of the effective processes in turning a healthy stomach tissue into a tumor tissue.  相似文献   
48.
49.
Long noncoding RNAs (lncRNAs) have been demonstrated to regulate a variety of cell processes and involve in the development and progression of colorectal cancer (CRC). Recently, the circulating lncRNAs have emerged as minimally invasive biomarkers for cancer diagnosis and prognosis. We aimed to examine the plasma expression level of long noncoding RNAs lnc-ATB, lnc-CCAT1, and lnc-OCC-1 in CRC patients and evaluate the clinical values. A total of 74 pretreatment CRC and 74 healthy blood biopsies were subjected to differentially evaluate the expression levels of three lncRNAs (OCC-1, CCAT1, and ATB). Briefly, after plasma separation and total RNA extraction, RNAs were reversely transcribed to complementary DNA followed by amplification using a quantitative real-time polymerase chain reaction technique for lncRNA expression analysis. The results showed that the expression levels of lnc-ATB (p < 0.001) and CCAT1 (p = 0.024), but not OCC-1 (p = 0.24), were significantly upregulated in the CRC compared with the healthy group. The calculated AUC of ROC was 0.78 (95% confidence interval [CI]: 0.811–0.94) for lnc-ATB and 0.64 (95% CI: 0.811–0.94) for CCAT1, which were indicative of a high discriminatory power (p < 0.001). The highest accuracy for lncRNA-ATB was obtained at a cutoff point of 2.5, which corresponded to sensitivity and specificity of 82% and 75%, respectively. Our results suggested a significant accuracy of lncRNA-ATB and lncRNA-CCAT1 in distinguishing CRC patients from healthy individuals.  相似文献   
50.
It is well known that embryo implantation is a critical process in which embryo should be able to reach and attach to endometrium. Until now, various types of factors are involved in the regulation of this process. S100 proteins are calcium-binding proteins, which have vital roles in embryo implantation and have been considered as possible candidate markers for endometrial receptivity. However, studies regarding mode of actions of these proteins are scarce and more mechanistic insights are needed to clarify exact roles of each one of the S100 protein family. Understanding of function of these proteins in different compartments, stages, and phases of endometrium, could pave the way for conducting studies regarding the therapeutic significance of these proteins in some disorders such as recurrent implantation failure. In this review, we outlined roles and possible underlying mechanisms of S100 protein family in embryo implantation.  相似文献   
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