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131.
Transforming growth factor-β (TGF-β) is known to promote tumor migration and invasion. Bone morphogenetic proteins (BMPs) are members of the TGF-β family expressed in a variety of human carcinoma cell lines. The role of bone morphogenetic protein 9 (BMP9), the most powerful osteogenic factor, in osteosarcoma (OS) progression has not been fully clarified. The expression of BMP9 and its receptors in OS cell lines was analyzed by RT-PCR. We found that BMP9 and its receptors were expressed in OS cell lines. We further investigated the influence of BMP9 on the biological behaviors of OS cells. BMP9 overexpression in the OS cell lines 143B and MG63 inhibited in vitro cell migration and invasion. We further investigated the expression of a panel of cancer-related genes and found that BMP9 overexpression increased the phosphorylation of Smad1/5/8 proteins, increased the expression of ID1, and reduced the expression and activity of matrix metalloproteinase 9 (MMP9) in OS cells. BMP9 silencing induced the opposite effects. We also found that BMP9 may not affect the chemokine (C-X-C motif) ligand 12 (CXCL12)/C-X-C chemokine receptor type 4 (CXCR4) axis to regulate the invasiveness and metastatic capacity of OS cells. Interestingly, CXCR4 was expressed in both 143B and MG63 cells, while CXCL12 was only detected in MG63 cells. Taken together, we hypothesize that BMP9 inhibits the migration and invasiveness of OS cells through a Smad-dependent pathway by downregulating the expression and activity of MMP9.  相似文献   
132.
133.
The most remarkable developmental event during metamorphosis in flatfish (Pleuronectiformes) is the migration of their eyes; one eye migrates upwards, then passes through the dorsal midline, and finally stops on the other side. In this study, we determined that the ratio of the movable eye diameter on the transverse axis (DTA) to that on the vertical axis (DVA) increased during the metamorphosis of Paralichthys olivaceus and Solea senegalensis. Based on the recently proposed hypothesis that eye migration of flatfishes is caused by the push force from the proliferated tissue of the suborbital region, we postulated that the eye shape change is a result of the same force. Measurements of eye proportions in 20 species of adult flatfishes revealed that the DTA is constantly larger than the DVA, suggesting that the mechanisms of eye shape change and eye migration driven by proliferating cells in the suborbital tissue are universal among flatfishes.  相似文献   
134.
Powdery mildew is the most widespread disease of pea (Pisum sativum L.) and causes severe economic losses worldwide. Recessively inherited er1 powdery mildew resistance, successfully used for decades in pea breeding programs, has recently been shown to originate from the loss of function of the PsMLO1 gene. Five er1 alleles, each corresponding to a different PsMLO1 null mutation, have been characterized to date in pea germplasm. In order to aid er1 selection, we aimed to identify functional markers which target PsMLO1 polymorphisms directly responsible for the resistant phenotype. Highly informative cleaved amplified polymorphic sequence (CAPS), derived cleaved amplified polymorphic sequence (dCAPS), sequence tagged site (STS) and high-resolution melting (HRM) markers were developed which enable the selection of each of the five er1 alleles. Taken together, the results described here provide a powerful tool for breeders, overcoming limitations of previously reported er1-linked markers due to the occurrence of recombination with the resistance locus and/or the lack of polymorphism between parental genotypes. The HRM marker er1-5/HRM54 reported here, targeting a mutagenesis-induced er1 allele recently described by us, does not require manual processing after PCR amplification, and is therefore suitable for large-scale breeding programs based on high-throughput automated screening.  相似文献   
135.
136.

Background

Dental agenesis is the most common, often heritable, developmental anomaly in humans. Although WNT10A gene mutations are known to cause rare syndromes associated with tooth agenesis, including onycho-odontodermal dysplasia (OODD), Schöpf-Schulz-Passarge syndrome (SSPS), hypohidrotic ectodermal dysplasia (HED), and more than half of the cases of isolated oligodontia recently, the genotype-phenotype correlations and the mode of inheritance of WNT10A mutations remain unclear. The phenotypic expression with WNT10A mutations shows a high degree of variability, suggesting that other genes might function with WNT10A in regulating ectodermal organ development. Moreover, the involvement of mutations in other genes, such as EDA, which is also associated with HED and isolated tooth agenesis, is not clear. Therefore, we hypothesized that EDA mutations interact with WNT10A mutations to play a role in tooth agenesis. Additionally, EDA, EDAR, and EDARADD encode signaling molecules in the Eda/Edar/NF-κB signaling pathways, we also checked EDAR and EDARADD in this study.

Methods

WNT10A, EDA, EDAR and EDARADD were sequenced in 88 patients with isolated oligodontia and 26 patients with syndromic tooth agenesis. The structure of two mutated WNT10A and two mutated EDA proteins was analyzed.

Results

Digenic mutations of both WNT10A and EDA were identified in 2 of 88 (2.27%) isolated oligodontia cases and 4 of 26 (15.38%) syndromic tooth agenesis cases. No mutation in EDAR or EDARADD gene was found.

Conclusions

WNT10A and EDA digenic mutations could result in oligodontia and syndromic tooth agenesis in the Chinese population. Moreover, our results will greatly expand the genotypic spectrum of tooth agenesis.  相似文献   
137.
This study aims to evaluate the effects of Remifemin (isopropanolic extract of Cimicifuga Racemosa) on postmenopausal osteoporosis. 120 female Sprague-Dawley rats were randomly assigned to four groups: sham surgery with vehicle, ovariectomy with vehicle, ovariectomy with estradiol valerate, or ovariectomy with Remifemin. Daily oral administrations of the vehicle, estradiol valerate, or Remifemin began 2 weeks after surgery and lasted to 4, 8, or 12 weeks. Ten rats in each group were sacrificed at each timestep with assessment of bone mineral density, trabecular bone structure, and biomechanical parameters of the femur and lumbar vertebra. Bone turnover markers were evaluated 12 weeks after surgery. Both drugs prevented bone density loss in the distal end of the femur and preserved the trabecular bone structure in both the lumbar vertebra and distal end of the femur following ovariectomy. Both drugs protected bone stiffness at the tested regions and reduced bone reabsorption in ovariectomized rats. The preventive effects of Remifemin against bone-loss can rival those of estradiol valerate if treatment duration is adequately extended. In conclusion, Remifemin may demonstrate equivalent effects to estradiol valerate in terms of preventing postmenopausal osteoporosis.  相似文献   
138.

Background

The world’s first reported patient infected with avian influenza H7N9 was treated at the Fifth People’s Hospital of Shanghai. Shortly thereafter, several other cases emerged in the local area. Here, we describe the detailed epidemiological and clinical data of 6 cases of avian influenza H7N9.

Methods and Findings

We analyzed the epidemiologic and clinical data from clustered patients infected with H7N9 in the Minhang District of Shanghai during a 2-week period. Of the 6 patients, 2 were from a single family. In addition, 3 patients had a history of contact with poultry; however, all 6 patients lived in the proximity of 2 food markets where the H7N9 virus was detected in chickens and pigeons. The main symptoms were fever, cough, and hemoptysis. At onset, a decreased lymphocyte count and elevated creatine kinase, lactate dehydrogenase, procalcitonin, and C-reactive protein levels were observed. As the disease progressed, most patients developed dyspnea and hypoxemia. Imaging studies revealed lung consolidation and multiple ground-glass opacities in the early stage, rapidly extending bilaterally. All patients were treated with oseltamivir tablets beginning on days 3–8 after onset. The main complications were as follows: acute respiratory distress syndrome (ARDS; 83.3%), secondary bacterial infection (66.7%), pleural effusion (50%), left ventricular failure (33.3%), neuropsychiatric symptoms (33.3%), and rhabdomyolysis (16.7%). Of the 6 patients, 4 died of ARDS, with 2 patients recovering from the infection.

Conclusions

An outbreak of H7N9 infection occurred in the Minhang District of Shanghai that easily progressed to acute respiratory distress syndrome. Two cases showed family aggregation, which led us to identify the H7N9 virus and indicated that human transmission may be involved in the spread of this infection.  相似文献   
139.

Background

Fusarium head blight (FHB), mainly caused by Fusarium graminearum, substantially reduces wheat grain yield and quality worldwide. Proteins play important roles in defense against the fungal infection. This study characterized differentially expressed proteins between near-isogenic lines (NILs) contrasting in alleles of Fhb1, a major FHB resistance gene in wheat, to identify proteins underlining FHB resistance of Fhb1.

Methods

The two-dimensional protein profiles were compared between the Fusarium-inoculated spikes of the two NILs collected 72 h after inoculation. The protein profiles of mock- and Fusarium-inoculated Fhb1+NIL were also compared to identify pathogen-responsive proteins.

Results

Eight proteins were either induced or upregulated in inoculated Fhb1+NIL when compared with mock-inoculated Fhb1+NIL; nine proteins were either induced or upregulated in the Fusarium-inoculated Fhb1+NIL when compared with Fusarium-inoculated Fhb1NIL. Proteins that were differentially expressed in the Fhb1+NIL, not in the Fhb1NIL, after Fusarium inoculation included wheat proteins for defending fungal penetration, photosynthesis, energy metabolism, and detoxification.

Conclusions

Coordinated expression of the identified proteins resulted in FHB resistance in Fhb1+NIL. The results provide insight into the pathway of Fhb1-mediated FHB resistance.  相似文献   
140.

Objective

This study evaluated the effects of ultrasound combined with the homemade nitric oxide (NO) micro-bubble destruction on the in vitro proliferation, apoptosis, and migration of mesenchymal stem cells (MSCs). Furthermore, we studied whether or not irradiation of the NO micro-bubble combined with bone-marrow derived MSC infusion had a better effect on treating myocardial infarction. The possible mechanism of MSC delivery into the infarcted myocardium was also investigated.

Methods

The murine bone marrow-derived MSCs were isolated, cultured, irradiated, and combined with different concentrations of NO microbubbles. MTT proliferation assay, annexin V-FITC apoptosis detection, migration assay, and RT-PCR were performed 24 h after the irradiation. The NO micro-bubbles was a intravenously injected, followed by the infusion of MSCs, which were labeled by CM-Dil. Myocardium was harvested 48 h later and the distribution of MSCs was observed by laser scanning confocal microscope after frozen sectioning. Echocardiography, histological examination, RT-PCR, and western blotting were performed four weeks after the cell transplantation.

Results

Ultrasound combined with 1:70 NO micro-bubbles had no significant impact on the proliferation or apoptosis of MSCs. Transwell chamber findings demonstrated that MSCs migrated more efficiently in group that underwent ultrasound combined with 1:70 NO micro-bubbles. The Real-time PCR results indicated that the expression of CXCR4 was much higher in the group undergoing ultrasound combined with 1:70 NO micro-bubbles. The normalized fluorescence intensity greatly increased in the group of US+NO micro-bubbles and the cardiac function was also markedly improved. Immunohistochemical staining showed that the capillary density was much greater in the group of US+NO micro-bubbles as compared to that of the other groups. RT-PCR and western blotting also revealed a higher SDF-1 and VEGF expression in the group of US+NO micro-bubbles.

Conclusions

NO micro-bubbles could be used in the cell transplantation, which efficiently promoted the MSC homing into the infarcted myocardium.  相似文献   
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