RESUMO
BACKGROUND: Scientific research ability (SRA) is very important for clinical postgraduates. However, the factors affecting students' SRA are constantly changing with the development of medicine. The aim of this study was to investigate the current situation of SRA in clinical postgraduates and exploring the potential factors and the corresponding countermeasures under the background of new medical science. METHODS: A total of 133 postgraduates (first- or second-year) were investigated by questionnaire in the Second Affiliated Hospital of Fujian Medical University. All results were analyzed by R software. RESULTS: In terms of the SRA, academic-degree postgraduate students (ADPSs) were significantly better than professional-degree postgraduate students (PDPSs) (P = 0.001), the students with scientific research interest were remarkably better than those without scientific research interest (P = 0.004), the students who mastered statistical analysis methods were more prominent than those who did not (P = 0.007), the students with paper-writing skills were obviously superior to those without it (P = 0.003), and the second-year students were notably better than the first-year students (P = 0.003). Stratified analysis by the above factors except the degree type showed no significant difference in the first-year postgraduates. In the second-year postgraduates, the ADPSs were remarkably superior to the PDPSs (P = 0.002), the students with scientific research interest were obviously better than those without scientific research interest (P = 0.014), the students with more time investment in scientific research were more prominent than those with less time investment in scientific research (P = 0.025), the students with paper-writing skills were notably superior to those without it (P = 0.031), and the students with plotting ability were better than those without it (P = 0.013). CONCLUSION: The important factors affecting the SRA of clinical postgraduates include the degree type, the grade of student, scientific research interest, time investment in scientific research, statistical analysis methods, paper-writing skills, plotting ability. In short, earlier systematic SRA training contributes to the improvement of SRA in clinical postgraduates, especially in PDPSs.
Assuntos
Medicina , Estudantes , Humanos , Inquéritos e Questionários , Currículo , Educação de Pós-Graduação em Medicina/métodosRESUMO
Nucleotide-binding oligomerization domain-like receptors (NLRs) are crucial types of innate immune sensors and well known for their critical roles in the immune system. However, how NLRP2 functions in the progression of cancer is largely unknown. Here, we identified NLRP2 as an antioncogene in lung adenocarcinoma (LUAD) cells. Gain- and loss-of-function studies revealed that NLRP2 silencing promoted cell proliferation and migration by stimulating NF-kB signaling in the microenvironment, which induced epithelial-to-mesenchymal transition (EMT) phenotype and cytoskeleton reorganization in LUAD cells. The addition of the NF-kB inhibitor rescued the function of NLRP2 on EMT. Moreover, NLRP2 increased the level of cofilin phosphorylation and repressed subsequent F-actin reorganization. Consistently, the in vivo study showed that NLRP2 played an inhibitory role in forming metastasis foci. Taken together, NLRP2 inhibited cell proliferation and migration by regulating EMT in LUAD cells, demonstrating the essential function of NLRP2 in the development of LUAD.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Adenocarcinoma de Pulmão , Proteínas Reguladoras de Apoptose , Neoplasias Pulmonares , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adenocarcinoma de Pulmão/genética , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Humanos , Neoplasias Pulmonares/patologia , Microambiente TumoralRESUMO
Nucleotide-binding oligomerization domain (NOD)-like receptor type 2 protein (NLRP2) was reported to inhibit NF-κB in response to inflammatory stimuli, but its role in tumors remains elusive. We screened out NLRP2 from mouse models of breast cancer metastasis. Bioinformatics analysis showed NLRP2 expression was positively correlated with survival rate and negatively correlated with the potential of cancer metastasis. Its significance in Triple-Negative Breast Cancer (TNBC) was investigated by gain- and loss-of-function studies in vivo and vitro. Re-expression of NLRP2 dramatically inhibited the growth and metastasis of the xenograft model of MDA-MB-231 cells. Mechanically, NLRP2 confined hnRNPK within cytoplasm, which in turn blocked vimentin mRNA production. Not only that, NLRP2 further enhanced the H2O2-induced high level of p53&Bax and hence dramatically increased the apoptosis rate (fivefold). Likewise, carboplatin-treated cells showed decreased cell viability, suggesting that patients of TNBC with high level of NLRP2 respond well to chemotherapeutics. Under the stimulus of H2O2, NLRP2-hnRNPK no longer stayed in the cytoplasm, but entered the nucleus to increase the expression of p53 and hence enhanced corresponding apoptosis effect, increasing Bax expression. It suggested that NLRP2 helps p53 enter the nucleus to induce apoptosis. This study revealed a novel function of NLRP2 that modulated oncogenic and anti-oncogenic characteristics of hnRNPK, and provided a new biomarker for TNBC chemotherapy.
Assuntos
Neoplasias de Mama Triplo Negativas , Animais , Camundongos , Humanos , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/patologia , Proteína Supressora de Tumor p53 , Proteína X Associada a bcl-2/metabolismo , Peróxido de Hidrogênio/metabolismo , NF-kappa B/metabolismo , Apoptose , Linhagem Celular Tumoral , Proliferação de Células , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismoRESUMO
Corticotrophin-releasing hormone (CRH) has been demonstrated to participate in vascular inflammation and permeability. Our previous studies have shown that blockade of S1PR2 or CRHR1 inhibited H2O2-induced brain endothelial hyperpermeability via inhibiting cPLA2 phosphorylation. However, little is known about the linkage between S1PRs and CRHR1 in oxidative stress-induced cerebrovascular endothelial hyperpermeability. Here we observed the opposite effects of S1PR2 to those of S1PR3 on the monolayer permeability of bEnd3 cells in response to H2O2. Interestingly, activation of CRHR1 was found to reverse the effects resulting from blockade/silencing of both S1PR2 and S1PR3. In bEnd3 monolayer, blockade/knockdown of S1PR2 reduced the endothelial hyperpermeability and suppressed the tight junction protein ZO-1 redistribution caused by H2O2, along with the inhibition of p38, ERK and cPLA2 phosphorylation. On the contrary, suppression/silencing of S1PR3 further promoted H2O2-induced endothelial hyperpermeability and ZO-1 redistribution, accompanied by the increased phosphorylation of p38, ERK and cPLA2. In the presence of CRH, the effects resulting from the suppression of both S1PR2 and S1PR3 were abolished. Our results elucidate a possible linkage between CRHR1 and S1PR2/S1PR3 involving in the regulation of endothelial monolayer permeability under oxidative stress condition.
Assuntos
Hormônio Liberador da Corticotropina , Peróxido de Hidrogênio , Estresse Oxidativo , Animais , Linhagem Celular , Hormônio Liberador da Corticotropina/metabolismo , Células Endoteliais/metabolismo , Peróxido de Hidrogênio/farmacologia , Camundongos , Permeabilidade , Receptores de Hormônio Liberador da Corticotropina/metabolismo , Receptores de Esfingosina-1-Fosfato/metabolismoRESUMO
Supervillin (SVIL) is an actin-binding and membrane-associated protein, which belongs to villin/gelsolin family. It has been reported that SVIL was involved in the regulation of macrophages' movement and lipopolysaccharide (LPS) increased the SVIL mRNA expression in neutrophils, but the underlying mechanisms remain unknown. This work investigated the underlying molecular mechanisms of LPS regulating SVIL expression in macrophages and hence the possible role of SVIL in LPS-induced inflammation. We found that in THP-1-derived macrophages, LPS obviously increased SVIL mRNA and protein expression. Inhibition of TLR4 by Resatorvid (Res) remarkably reversed the LPS-induced SVIL expression. Additionally, inhibition of ERK1/2 signaling pathway (by U0126 or GDC-0994) and NF-κB (by BAY) significantly reduced the LPS-induced SVIL expression. Interestingly, down-regulation of SVIL by SVIL-specific shRNAs significantly attenuated the expression of IL-6, IL-1ß & TNF-α induced by LPS at both mRNA and protein levels. Furthermore, we also observed that SVIL knockdown decreased the proportion of cells in G2/M phase and increased the proportion of cells in S & G0-1 phase of THP-1 derived macrophages, but did not influence the cell viability. Taken together, we demonstrated that LPS induced the expression of SVIL via activating TLR4/NF-κB and ERK1/2 MAPK pathways, and SVIL participated in the inflammatory response of LPS-induced IL-6, IL-1ß and TNF-α upregulation in macrophages.
Assuntos
Inflamação/imunologia , Lipopolissacarídeos/imunologia , Macrófagos/imunologia , Proteínas de Membrana/imunologia , Proteínas dos Microfilamentos/imunologia , Humanos , Células THP-1RESUMO
The difference in compatibility at the molecular level can lead to a change of microphase separation structure of thermoplastic polyurethanes blend systems, which will improve their thermal and mechanical properties. In this study, TDI-polyester based TPU was blended with MDI-polyether-based TPU and MDI-polyester based TPU, with different ratios. In the blend system, the obvious reduction of the melting temperature of the high-temperature TDI-polyester based TPU component indicates its hard segments can be mutually integrated with the other component. For TDI-polyester based TPU/MDI-polyether based TPU blends, their similar hard segment ratio and similar chemical structure of the soft segment give the molecular chains of the two components better compatibility. The aggregation structure of the two kinds of chains can rearrange at the molecular level which makes the hard domains mutually integrate to form a new phase separation structure with larger phase region distance. As a result, the yield strength of this blend increased by almost 143% when the elongation at break was only reduced by 12%. In contrast, the other group of blends still partly maintain their respective micro domains, forming a weak interface and leading to a decreased of elongation at break.