Time filter

Source Type

Long Y.,Xiamen University | Long Y.,Translational Medicine Center | Cao B.,Xiamen University | Wang Y.,Xiamen University | Luo D.,Xiamen University
Parasites and Vectors | Year: 2016

Background: Angiostrongyliasis caused by the rat lungworm, Angiostrongylus cantonensis (A. cantonensis), has globally spread from the traditional epidemic areas. The small intestine is the site where the third-stage larvae (L3) of this worm entered the host body, and parasite proteases are involved in this process. Ac-cathB-2, a cathepsin B-like cysteine of A. cantonensis, was formerly isolated from the insoluble part of fragmentised Escherichia coli without activity. The unplanned low activity of prokaryotic expression proteins and difficulties in genetic modification hindered understanding the function of this protein. Methods: The recombinant Ac-cathB-2 was expressed and harvested from 293 T cells and the enzymatic property and the effects of processing on the activity of the recombinant protease were investigated in vitro. The expression of Ac-cathB-2 in response to external stimulation was assessed, and the function of this protease during host gut penetration was observed by using antiserum for inhibition. Results: Of the life-cycle stages studied, L3 expressed the highest level of Ac-cathB-2 gene and released the corresponding gene product from the body. The expression of this gene was rapidly upregulated after incubating L3 in small intestine homogenate of rat. Recombinant Ac-cathB-2 was harvested from 293 T cell culture medium. This protease was activated by pepsin-HCl and the enabled Ac-cathB-2 could subsequently digest laminin and fibronectin readily. Moreover, the small intestine isolated from rat was disrupted after incubating with the activated Ac-cathB-2, resulting in the detachment of epithelial cells. Antiserum treatment inhibited the hydrolytic ability of recombinant Ac-cathB-2 by 82.7 %, and also reduced the tissue penetration of activated L3 by 41.2 %. Additionally, pre-incubation of L3 with artificial gastric acid increased the number of penetrating larvae by 53.2 %, and this alteration could be partly blocked by antiserum treatment. Conclusion: We believe that Ac-cathB-2 from A. cantonensis might help the worm to penetrate the rat gut, because the protease was able to degrade the tissue components of host. Nevertheless, our results further indicated that host pepsin played a beneficial role in this process by cleaving Ac-cathB-2 for activation. Thus, Ac-cathB-2 may probably represent an important target for the control of A. cantonensis infection. © 2016 Long et al. Source

Fang C.,Nanjing Medical University | Li L.,Translational Medicine Center | Li J.,Nanjing Medical University
International Journal of Molecular Sciences | Year: 2016

The epidermis is an important tissue in Homo sapines and other animals, and an abnormal epidermis will cause many diseases. Phosphatase 2A (PP2A) is an important serine and threonine phosphatase. The α isoform of the PP2A catalytic subunit (Ppp2ca gene encoding PP2Acα) is critical for cell proliferation, growth, metabolism and tumorigenesis. However, to date, no study has revealed its roles in epidermis development. To specifically investigate the roles of PP2Acα in epidermis development, we first generated Ppp2caflox/flox transgenic mice, and conditionally knocked out Ppp2ca in the epidermis driven by Krt14-Cre. Our study showed that Ppp2caflox/flox; Krt14-Cre mice had significant hair loss. In addition, histological analyses showed that the morphogenesis and hair regeneration cycle of hair follicles were disrupted in these mice. Moreover, Ppp2caflox/flox; Krt14-Cre mice had smaller size, melanin deposition and hyperproliferation at the base of the claws. Accordingly, our study demonstrates that PP2Acα plays important roles in both hair follicle and epidermis development. Additionally, the Ppp2caflox/flox mice generated in this study can serve as a useful transgene model to study the roles of PP2Acα in other developmental processes and diseases. © 2016 by the authors; licensee MDPI, Basel, Switzerland. Source

Zhang R.,Harbin Medical University | Chen X.,Harbin Medical University | Li P.,Harbin Medical University | Lu X.,Harbin Medical University | And 5 more authors.
Molecular Cytogenetics | Year: 2016

Background: Karyotyping is the gold standard cytogenetic method for detection of ring chromosomes. In this study we report the molecular characterization of a novel ring 6 (r6) chromosome in a six-year-old girl with severe mental retardation, congenital heart disease and craniofacial abnormalities. Methods: Cytogenetic analysis was performed by conventional karyotyping. Molecular genetic analyses were performed using high-resolution chromosome microarray analysis (CMA) and next generation sequencing (NGS). OMIM, UCSC and PubMed were used as reference databases to determine potential genotype to phenotype associations. Results: Peripheral blood and skin fibroblast karyotyping revealed the presence of a dominant cell line, 46,XX,(r6)(p25.3;q27) and a minor cell line 45,XX,-6. Molecular karyotyping using NGS identified 6p25.3 and 6q27 subtelomeric deletions of 1.78 Mb and a 0.56 Mb, respectively. Based on the known genes located within the r6 deletion interval 6q25.3-pter, genotype to phenotype association studies found compelling evidence to suggest that hemizygous expression of disease genes FOXC1, FOXF2, IRF4 and GMDS was the main underlying cause of the patient's phenotype. We further speculate that the severity of the patient's symptoms may have been exacerbated by low-level instability of the r6 chromosome. Conclusion: This is the first report of a novel r6 chromosome characterized at the molecular level using NGS. © 2016 Zhang et al. Source

Yang J.,Breast Disease Center | Yu H.,Breast Disease Center | Zhang L.,Translational Medicine Center | Deng H.,Translational Medicine Center | And 5 more authors.
Oncology Reports | Year: 2016

Although human breast ducts and terminal ductal lobular units (TDLUs) share the same cell types, ample evidence shows that TDLUs are the predominant site for the origin of breast cancer. Yet, there is still limited information concerning the molecular mechanisms. Analysis of transcriptomic profiles in TDLUs may provide insight into early breast tumorigenesis. We compared genome-wide expression profiles of 8 matched sets of breast main duct and TDLU samples, using significance analysis of microarray (SAM) software to screen differentially expressed genes (DEGs) with fold-change >2.0 and q-value <0.05. Moreover, we used Gene Ontology for functional enrichment analysis. We identified 472 DEGs between the two tissue types, and confirmed 17 randomly chosen DEGs by quantitative reverse transcription-PCR (qRT-PCR). Notably, hormone-related pathways were highly enriched in the TDLU samples, including various hormone-related DEGs that are associated with breast carcinogenesis and tumor progression. Oncogenic upregulation in TDLUs indicates a potential inappropriate or excessive response to successive hormone stimulus during the proliferation, differentiation and lactation cycles of the human mammary gland. Imbalanced hormone reactions may finally result in the early onset of neoplastic transformation that occurs mostly in breast TDLUs. Source

Gao B.-X.,PUMC Hospital | Gao B.-X.,Translational Medicine Center | Li M.-X.,PUMC Hospital | Li M.-X.,Translational Medicine Center | And 11 more authors.
Acta Academiae Medicinae Sinicae | Year: 2011

Objective: To determine the potential urinary biomarkers of metabolic syndrome (MS) with early renal injury and establish diagnostic models by magnetic bead-based separation and matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS). Methods: Participants were selected from the epidemiologic study on MS and renal involvement among residents in Pinggu district, Beijing. Eight-hour overnight urine samples were fractionated by means of magnetic bead-based weak cation exchange chromatography and subsequently analyzed with MALDI-TOF-MS. Wilcoxon test and random forests were used to screen differential protein peaks of MS patients with early renal injury, then combined with genetic algorithm and support vector machine, respectively, to establish diagnostic models. Results: Totally 54 cases of MS without renal injury and 46 cases of MS with early renal injury were enrolled. Totally twenty protein peaks were up-regulated in the urine of MS patients with early renal injury by Wilcoxon test (P < 0.05); random forests algorithm revealed twelve protein peaks up-regulated in the urine of MS patients with early renal injury (importance value of mean decrease in accuracy >0.005). Genetic algorithm based model showed 82.6% sensitivity, 84.3% specificity, and 83.5% accuracy by a 10-fold cross-validation in identifying MS patients with early renal injury; correspondingly, the support vector machine based model reported 89.2% sensitivity, 81.1% specificity and 85.5% accuracy. Four protein peaks were included in two diagnostic models with mass-to-charge ratios of 2756.98, 3019.11, 9077.04, and 10054.26. Conclusions: The urinary proteome patterns of MS with early renal injury were successfully established with magnetic bead-based separation and MALDI-TOF-MS technology. A series of urinary differential expressing protein peaks were identified with bioinformatics tools. Diagnostic models combining cluster of protein peaks are capable of differentiating MS patients with early renal injury from those without renal injury. The different urine protein excretion patterns revealed in this study provide urinary candidate biomarkers of MS patients with early renal injury for future identification and biological roles investigation. Source

Discover hidden collaborations