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Peanut scorch spot caused by Leptosphaerulina arachidicola is one of the most severe leaf diseases of peanut that causes significant yield loss. Here, we report the first high-quality genome sequence of L. arachidicola JB313 isolated from an infected peanut leaf in China. The genome size is 47.66 Mb, consisting of 65 scaffolds (N50 length = 1.58 Mb) with a G+C content of 49.05%. The information in this report will provide a reference genome for future studies on the peanut scorch spot pathogen in peanut.
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Arachis , Ascomicetos , Genoma Fúngico , Doenças das Plantas/microbiologia , Arachis/microbiologia , Ascomicetos/genética , China , Folhas de PlantaRESUMO
Root-knot nematode (Meloidogyne spp.) is one of the important disease of medicinal plant cultivation and seriously hinders the sustainable development of traditional Chinese medicine industry. We introduced the main species, identification methods and control strategies of root-knot nematode diseases in the medicinal plants in this study. Identifications of morphology and molecular were the main tools for the distinction of root-knot nematodes at present. This study stated that integrated system was established for root-knot nematode control, including that integrated control technique was the first step, disease-resistant varieties with high yield were the basis, and normalized patterns of cultivation and management were the measure. These strategies would improve the sustainable development of medicinal plants and environmental protection.
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Doenças das Plantas/prevenção & controle , Doenças das Plantas/parasitologia , Plantas Medicinais/parasitologia , Tylenchoidea , Animais , Raízes de Plantas/parasitologiaRESUMO
Background: Newly identified as a radiological concept, interstitial lung abnormalities (ILA) is emerging as a prognostic factor for lung cancer. Yet, debates persist regarding the prognostic significance of ILA in lung cancer. Our inaugural meta-analysis aimed to investigate the correlation between ILA and lung cancer outcomes, offering additional insights for clinicians in predicting patient prognosis. Methods: Articles meeting the criteria were found through PubMed, the Cochrane Library, EMBASE, and Web of Science by February 29, 2024. The outcomes evaluated were the survival rates such as overall survival (OS), disease-free survival (DFS), progression-free survival (PFS), and cancer-specific survival (CSS). Results: A total of 12 articles with 4416 patients were included in this meta-analysis. The pooled results showed that lung cancer patients with interstitial lung abnormalities had an inferior OS (n=11; HR=2.22; 95% CI=1.68-2.95; P<0.001; I2 = 72.0%; Ph<0.001), PFS (n=3; HR=1.59; 95% CI=1.08-2.32; P=0.017; I2 = 0%; Ph=0.772), and CSS (n=2; HR=4.00; 95% CI=1.94-8.25; P<0.001; I2 = 0%; Ph=0.594) than those without, however, the ILA was not significantly associated with the DFS (n=2; HR=2.07; 95% CI=0.94-7.02; P=0.066; I2 = 90.4%; Ph=0.001). Moreover, lung cancer patients with ILA were significantly correlated with male (OR=2.43; 95% CI=1.48-3.98; P<0.001), smoking history (OR=2.11; 95% CI=1.37-3.25; P<0.001), advanced age (OR=2.50; 95% CI=1.56-4.03; P<0.001), squamous carcinoma (OR=0.42; 95% CI=0.24-0.71; P=0.01), and EGFR mutation (OR=0.50; 95% CI=0.32-0.78; P=0.002). The correlation between ILA and race, stage, ALK, however, was not significant. Conclusion: ILA was a availability factors of prognosis in patients with lung cancers. These findings highlight the importance of early pulmonary fibrosis, namely ILA for prognosis in patients with lung cancer, and provide a partial rationale for future clinical work.
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Introduction: Early and accurate identification of pathogens is essential for improved outcomes in patients with viral encephalitis (VE) and/or viral meningitis (VM). Methods: In our research, Metagenomic next-generation sequencing (mNGS) which can identify viral pathogens unbiasedly was performed on RNA and DNA to identify potential pathogens in cerebrospinal fluid (CSF) samples from 50 pediatric patients with suspected VEs and/or VMs. Then we performed proteomics analysis on the 14 HEV-positive CSF samples and another 12 CSF samples from health controls (HCs). A supervised partial least squaresdiscriminant analysis (PLS-DA) and orthogonal PLS-DA (O-PLS-DA) model was performed using proteomics data. Results: Ten viruses in 48% patients were identified and the most common pathogen was human enterovirus (HEV) Echo18. 11 proteins overlapping between the top 20 DEPs in terms of P value and FC and the top 20 proteins in PLS-DA VIP lists were acquired. Discussion: Our result showed mNGS has certain advantages on pathogens identification in VE and VM and our research established a foundation to identify diagnosis biomarker candidates of HEV-positive meningitis based on MS-based proteomics analysis, which could also contribute toward investigating the HEV-specific host response patterns.
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Encefalite Viral , Enterovirus , Meningite Viral , Vírus , Humanos , Criança , Proteômica , Encefalite Viral/diagnóstico , Vírus/genética , Meningite Viral/diagnóstico , Enterovirus/genética , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Alpha-L-fucosidase-1 (FUCA1) has been demonstrated to play opposing regulatory roles in adenocarcinoma and non-adenocarcinoma. Moreover, recent studies reported that FUCA1 could decrease the invasion capability by downregulating matrix metalloproteinase 9 (MMP-9) expression. However, the potential role and prognostic significance of FUCA1 in esophageal squamous cell carcinoma (ESCC) have not yet been explored. AIM: To evaluate the status, association, and prognostic value of FUCA1 and MMP-9 expression in ESCC. METHODS: Patients who underwent esophagectomy for ESCC between January 1, 2014, and December 31, 2014 at Sun Yat-Sen University Cancer Center were enrolled. The expression status of FUCA1 and MMP-9 in cancerous tissues was detected using immunohistochemistry. In addition, the expression profiles of the FUCA1 and MMP-9 genes in non-metastatic ESCC were extracted from The Cancer Genome Atlas (TCGA) database. RESULTS: High expression of FUCA1 and MMP-9 was found in 90 patients (75.6%) and 62 patients (52.1%), respectively. In the high FUCA1 expression group, the constituent ratios of patients with stage III disease (61.1% vs 37.9%, P = 0.029), lymphatic invasion (62.2% vs 31.0%, P = 0.003), and high MMP-9 expression (60.0% vs 27.6%, P = 0.002) were significantly higher than those in the low FUCA1 expression group. In Kaplan-Meier univariate analysis, advanced tumor-node-metastasis stage (III, P = 0.001), positive regional lymph node metastasis (N+, P = 0.002), high FUCA1 expression (P = 0.001), and high MMP-9 expression (P = 0.002) were potential predictors of shorter overall survival (OS), which was similar to the results analyzed based on the TCGA database. Further Cox multivariate regression analyses still demonstrated that FUCA1 and MMP-9 expression levels were independent prognostic factors of OS [hazard ratio (HR): 0.484, 95% confidence interval (CI): 0.239-0.979; P = 0.044; and HR: 0.591, 95%CI: 0.359-0.973, P = 0.039, respectively]. CONCLUSION: FUCA1 cooperation with MMP-9 may have a major role in affecting the ESCC invasion and metastatic capability, and serve as a valuable prognostic biomarker in ESCC.
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BACKGROUND: Myelin oligodendrocyte glycoprotein (MOG) antibody-associated disease (MOGAD) is an autoimmune demyelinating disorder of the central nervous system. METHODS: Extracted proteins from 34 cerebrospinal fluid (CSF) samples [patients with MOGAD (MOG group, n = 12); healthy controls (HC group, n = 12); patients with MOG seronegative and metagenomics next-generation sequencing-negative inflammatory neurological diseases (IND group, n = 10)] were processed and subjected to label-free quantitative proteomics. Supervised partial least squares-discriminant analysis (PLS-DA) and orthogonal PLS-DA (O-PLS-DA) models were also performed based on proteomics data. Functional analysis of differentially expressed proteins (DEPs) was performed using Gene Ontology, InterPro, and Kyoto Encyclopedia Genes and Genomes. An enzyme-linked immunosorbent assay was used to determine the complement levels in serum from patients with MOGAD. RESULTS: Four hundred and twenty-nine DEPs (149 upregulated and 280 downregulated proteins) were identified in the MOG group compared to the HC group according to the P value and fold change (FC). Using the O-PLS-DA model, 872 differentially abundant proteins were identified with variable importance projection (VIP) scores > 1. Five proteins (gamma-glutamyl hydrolase, cathepsin F, interalpha-trypsin inhibitor heavy chain 5, latent transforming growth factor beta-binding protein 4 and leukocyte-associated immunoglobulin-like receptor 1) overlapping between the top 30 DEPs with top-ranked P value and FC and top 30 proteins in PLS-DA VIP lists were acquired. Functional analysis revealed that the dysregulated proteins in the MOG group were primarily involved in complement and coagulation cascades, cell adhesion, axon guidance, and glycosphingolipid biosynthesis compared to the HC group. CONCLUSION: The proteomic alterations in CSF samples from children with MOGAD identified in the current study might provide opportunities for developing novel biomarker candidates.
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Objective: This study sought to establish the diagnostic utility of performing a second biopsy using an magnetic resonance (MR)-guided percutaneous transthoracic needle biopsy (PTNB) approach in patients with suspicious malignant lung lesions that had already undergone an initial negative computed tomography (CT)-guided biopsy. Materials and Methods: This study evaluated 31 patients with suspicious lung lesions (18 males, 13 females; mean age: 62.1 ± 11.3 years) that had previously undergone CT-guided PTNB with negative pathological findings January 2015-November 2020. A final histopathological diagnosis was made based on resected lung lesion specimens or, when resection was not conducted, on clinical diagnosis following a ≥6-month follow-up. The diagnostic accuracy of MR-guided secondary lung biopsy was determined by comparing the lung biopsy results for each patient to their final diagnosis. Results: 1.0T open MR-guided secondary lung biopsy was performed for 31 lesions (20 central, 11 peripheral; mean size, 5.3 ± 2.0 cm). The pathological results revealed 20/31 (64.5%) lesions to be malignant (14 adenocarcinoma, 4 squamous cell carcinoma, and 2 small-cell lung cancer) as detected by 1.0T open MR-guided PTNB and confirmed by surgical pathology and clinical follow-up. There were three instances of biopsy-induced complications including hemorrhage in 6.5% of the patients (2/31) and pneumothorax in 3.2% of the patients (1/31). No patients experienced severe complications. Conclusion: For individuals with clinically suspicious lung lesions that initially received negative CT-guided PTNB findings, 1.0T open MR-guided secondary lung biopsy is a safe and effective secondary diagnostic approach.
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Biópsia Guiada por Imagem , Neoplasias Pulmonares , Idoso , Biópsia por Agulha/efeitos adversos , Feminino , Humanos , Biópsia Guiada por Imagem/métodos , Pulmão/diagnóstico por imagem , Pulmão/patologia , Neoplasias Pulmonares/patologia , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodosRESUMO
The aroma of peach fruit is predominantly determined by the accumulation of γ-decalactone and ester compounds. A previous study showed that the biosynthesis of these aroma compounds in peach fruit is catalyzed by PpAAT1, an alcohol acyltransferase. In this work, we investigated the key active site residues responsible for γ-decalactone and ester biosynthesis. A total of 14 candidate amino acid residues possibly involved in internal esterification and 9 candidate amino acid residues possibly involved in esterification of PpAAT1 were assessed via site-directed mutagenesis. Analyses of the in vitro enzyme activities of PpAAT1 and its site-directed mutant proteins (PpAAT1-SMs) with different amino acid residue mutations as well as the contents of γ-decalactone in transgenic tobacco leaves and peach fruits transiently expressing PpAAT1 and PpAAT1-SMs revealed that site-directed mutation of H165 in the conserved HxxxD motif led to lost enzymatic activity of PpAAT1 in both internal esterification and its reactions, whereas mutation of the key amino acid residue D376 led to the total loss of γ-decalactone biosynthesis activity of PpAAT1. Mutations of 9 and 7 other amino acid residues also dramatically affected the enzymatic activity of PpAAT1 in the internal esterification and esterification reactions, respectively. Our findings provide a biochemical foundation for the mechanical biosynthesis of γ-decalactone and ester compounds catalyzed by PpAAT1 in peach fruits, which could be used to guide the molecular breeding of new peach species with more favorable aromas for consumers.
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Plants in the juvenile state are more tolerant to adverse conditions. Constitutive expression of MicroRNA156 (miR156) prolonged the juvenile phase and increased resistance to abiotic stress, but also affected the architecture of transgenic plants. In this study, we investigated the possibility of subtle manipulation of miR156 expression in flowering plants, with the goal to increase tolerance to abiotic stress without altering the normal growth and development of transgenic plants. Transgenic tobacco plants expressing ZmmiR156 from maize were generated, driven either by the cauliflower mosaic virus (CaMV) 35S promoter or the stress-inducible ZmRab17 promoter. Expression of ZmmiR156 led to improved drought and salt tolerance in both 35S::MIR156 and Rab17::MIR156 transgenic plants, as shown by more vigorous growth, greater biomass production and higher antioxidant enzyme expression after a long period of drought or salt treatment, when compared to wild type and transgenic vector control plants. However, constitutive expression of ZmmiR156 also resulted in retarded growth, increased branching and delayed flowering of transgenic plants. These undesirable developmental changes could be mitigated by using the stress-inducible ZmRab17 promoter. Furthermore, under drought or salt stress conditions, expression of ZmmiR156 reduced the transcript level of NtSPL2 and NtSPL9, the genes potentially targeted by ZmmiR156, as well as that of CP1, CP2, and SAG12, the senescence-associated genes in tobacco. Collectively, our results indicate that ZmmiR156 can be temporally manipulated for the genetic improvement of plants resistant to various abiotic stresses.
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A series of AuPd/C catalysts were prepared and tested for the first time for active and stable dehydrogenation of a formic acid-ammonium formate (FA-AF) mixture. The catalysts with different Au-to-Pd molar ratios were prepared using a facile simultaneous reduction method and characterized using transmission electron microscopy (TEM), high-resolution TEM, energy dispersive X-ray spectroscopy, X-ray diffraction, and X-ray photoelectron spectroscopy. It was found that the catalytic activity and stability of the Au3Pd1/C catalyst was the best. The initial turnover frequency for the dehydrogenation of the FA-AF mixture over the Au3Pd1/C catalyst can reach 407.5 h-1 at 365 K. The reaction order with respect to FA and AF is 0.25 and 0.55, respectively. The apparent activation energy of dehydrogenation is 23.3 ± 1.3 kJ mol-1. The catalytic activity of the Au3Pd1/C catalyst remains ca. 88.0% after 4 runs, which is much better than the single Pd/C catalyst. The mechanism for the dehydrogenation is also discussed.
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Angiogenesis play a key roles in tumor growth, invasion and metastasis, and has become an attractive target for anticancer drug development. Though a number of anti-angiogenic agents had entered clinical trials, few of them could reproduce the spectacular results in cancer patients as that had been seen in pre-clinical tumor models. Therefore, exploring novel anti-angiogenic agents is highly deserved. SOX18, a member of the Sry-related HMG box-containing family of transcription factors, is expressed transiently in endothelial cells during the development of blood vessels. And mutations resulting in expression of dominant negative SOX18 have been shown to severely impair the vascular development. Recent research demonstrated that SOX18 is expressed during the initial steps of tumor vascularization and involved in regulation of the expression of the VEGF receptor Flk-1 and the vascular cell adhesion molecule-1 (VCAM-1). Moreover, allograft tumor growth in mice heterozygous for Ra(Op) (RaOp mice) which express a dominant negative mutant form of SOX18 (SOX18RaOp) that does not interact effectively with the endothelial partner protein MEF2C, was dramatically slower than that of wild-type mice. In this article, we postulate that recombinant cell-permeable dominant negative SOX18 mutants, prepared by fusion with protein transduction domains, would inhibit tumor angiogenesis with high efficiency by impairing endothelial tube formation. If the hypothesis was proved to be practical, the fusion proteins would show promise as single anti-angiogenic agents in cancer therapy.
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Proteínas de Grupo de Alta Mobilidade/genética , Mutação , Neoplasias/patologia , Neovascularização Patológica , Fatores de Transcrição/genética , Animais , Endotélio/patologia , Genes Dominantes , Proteínas HMGB/metabolismo , Heterozigoto , Camundongos , Modelos Biológicos , Modelos Teóricos , Proteínas Recombinantes/química , Fatores de Transcrição SOXF , Fatores de Transcrição/metabolismo , Molécula 1 de Adesão de Célula Vascular/genéticaRESUMO
OBJECTIVE: To evaluate dendritic cells induced immune response against hepatocellular carcinoma by pulsed CD34+ hematopoietic stem cells originated dendritic cells with p53 gene. METHODS: CD34+ hematopoietic stem cells were harvested after mobilization by chemotherapy and G-CSF. CD34+ hematopoietic stem cell apheresis was induced to differentiate into dendritic cells by cytokine cocktail IL-4,GM-CSF and TNF-alpha. On day 7, dendritic cells were transfected with plasmid pEGFP-C3/p53 DNA. The CTL response triggered by p53 pulsed dendritic cells was assayed by MTT method. RESULTS: Dendritic cells originated from CD34+ cell apheresis had typical dendritic stick and expressed high level CD1a, CD11c, CD80, CD86, and HLA-DR molecules. After being pulsed with p53 gene, dendritic cells expressed green fluorescence protein and immunofluorescence assay (Cy3 labeled anti-P53 antibody) showed that transfected dendritic cells emitted red fluorescence. Dendritic cells inducing CTL response against HMCC97 cells (P53 positive) and HepG2 cells (P53 negative) were assessed by MTT method. P53 pulsed dendritic cells could induce P53 specific immune response against HMCC97 cells and the cytotoxin rate was (49.3+/-4.6)% compared with pEGFP-C3 transfection group [(25.4+/-4.1)%] and control group [(24.8+/-3.8)%] (P < 0.05). However, P53 pulsed dendritic cells could not induce specific CTL against P53 expression negative HepG2 cells, which the cytotoxin rates were (30.8+/-4.6)%, (27.3+/-4.3)%, and (28.5+/-5.1)% respectively in pEGFP-C3/P53 transfection group, pEGFP-C3 transfection group and control group (P > 0.05). CONCLUSION: P53 gene transfecting hematopoietic stem cell apheresis originated dendritic cells could induce specific CTL response against P53-expressing hepatocellular carcinoma cells. P53 may be a potential candidate for dendritic cell based immunotherapy of cancer.
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Células Dendríticas/imunologia , Células-Tronco Hematopoéticas/citologia , Neoplasias Hepáticas/patologia , Proteína Supressora de Tumor p53/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Células Dendríticas/citologia , Humanos , Imunoterapia , Neoplasias Hepáticas/imunologia , Linfócitos T Citotóxicos/imunologia , TransfecçãoRESUMO
Epidermal growth receptor (EGFR)-targeted tyrosine kinase inhibitors (TKIs) have emerged as first-line drugs for advanced non-small-cell lung cancer (NSCLC) patients with EFGR mutations. However, most patients with NSCLC show acquired resistance to EGFR-TKIs, and low expression of NF1 is a mechanism of EGFR-TKI resistance in lung cancer. However, the mechanism by which NF1 is downregulated in EGFR-TKI-resistant NSCLC is unclear. Here, we found the increased expression of miR-641 in NSCLC cells and human NSCLC samples with resistance to TKI compared to those with sensitive to TKI. In addition, our in vitro experiments show that overexpression of miR-641 induces TKI resistance in NSCLC cells. Furthermore, we identified that miR-641 activates ERK signaling by direct targeting of neurofibromatosis 1 (NF1) in NSCLC cells. Our data show that overexpression of NF1 or silencing of ERK can block miR-641-induced resistance of NSCLC cells to erlotinib treatment. Importantly, our animal experiments show that combination of miR-641 inhibition and erlotinib treatment can significantly inhibit erlotinib-resistant NSCLC growth, inhibit proliferation and induce apoptosis compared to single-drug treatment. Our findings suggest that increased expression of miR-641 significantly contributes to erlotinib resistance development in NSCLC cells through activating ERK signaling by targeting NF1 and that inhibition of miR-641 may reverse acquired resistance of NSCLC cells to erlotinib treatment.
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Carcinoma Pulmonar de Células não Pequenas/genética , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/genética , MicroRNAs/genética , Neurofibromatose 1/genética , Interferência de RNA , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Modelos Animais de Doenças , Cloridrato de Erlotinib/farmacologia , Feminino , Humanos , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Sistema de Sinalização das MAP Quinases , Masculino , Pessoa de Meia-Idade , MutaçãoRESUMO
A nanocomposite with multi-walled carbon nanotubes (MWCNTs) coated with surface molecularly imprinted polymers (MIPs) poly(3-aminophenylboronic acid) (PAPBA) was successfully prepared via potentiodynamic electropolymerization and tested as an effective electrochemical material for epinephrine (EP) detection. The morphology and properties of the sensing material were characterized with scanning electron microscopy and electrochemical impedance spectroscopy. Compared with MWCNTs or non-imprinted polymers PAPBA modified MWCNTs electrodes, the PAPBA(MIPs)/MWCNTs modified electrode showed a lower charge transfer resistance and enhanced electrochemical performance for EP detection. The improved performance can be attributed to the large amount of specific imprinted cavities with boric acid group which can selectively adsorb EP molecule and the synergistic effect between MWCNTs and PAPBA(MIPs). The effects of pH, the molar ratio between monomer and template molecule, the cycle number of electropolymerization, and the accumulation time of the modified electrode on the sensing performance were investigated. It was found that under the optimal conditions, the PAPBA(MIPs)/MWCNTs sensor could effectively recognize EP from many possible interferents of higher concentration within a wide linear range of 0.2-800⯵mol·L-1, with low detection limit of 35â¯nmol·L-1, high sensitivity and good discrimination. The detection of EP in human serum and real injection samples using the PAPBA(MIPs)/MWCNTs sensor also gave satisfactory results.
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Ácidos Borônicos/química , Técnicas Eletroquímicas/métodos , Epinefrina/análise , Impressão Molecular/métodos , Nanocompostos/química , Nanotubos de Carbono/química , Carbono/química , Eletrodos , Epinefrina/sangue , Vidro/química , Humanos , Concentração de Íons de Hidrogênio , Nanotubos de Carbono/ultraestrutura , Polimerização , Reprodutibilidade dos TestesRESUMO
BACKGROUND: Previous studies have demonstrated that survival of patients with non-small cell lung cancer (NSCLC) with oligometastasis may benefit from local treatment. The purpose of this study was to compare the efficacy of local surgical treatment with systematic chemoradiotherapy in NSCLC with oligometastasis. METHODS: Data from a total of 172 patients with NSCLC with oligometastasis were collected at our Cancer Hospital from January 2006 to December 2016. The patients were divided into two groups: group A (82 cases) underwent primary surgical treatment and adjuvant chemotherapy was performed after operation, while group B (90 cases) received systematic chemotherapy and local radiotherapy. The median survival time (MST) and the 5-year survival rate of the two groups were compared and analyzed. The effects of various pathological types, surgical methods of the primary tumors and the site of oligometastasis were also analyzed. RESULTS: The MSTs in groups A and group B were 48 months and 18 months, respectively, and the 5-year survival rates were 21.1% and 7.6%, respectively (P<0.05). In group A, the survival rates were higher in patients with adrenal metastasis than patients with metastasis in the brain, bone, the liver or in other oligometastatic patients (P<0.05). There was no significant difference in the survival rate among the various pathological types or surgical methods of primary tumors (P>0.05). CONCLUSIONS: Local surgical treatment of primary lesions in NSCLC significantly prolonged overall survival and 5-year survival rates of patients with NSCLC with oligometastasis.
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Radiotherapy is frequently applied to control local tumors by mechanisms of direct killing tumor cells and inducing tumor vascular endothelial cells apoptosis. Recently, it has been demonstrated that survivin, an intracellular molecule with anti-apoptotic function, is widely expressed in human malignancies and its expression correlates with radioresistance in several tumors. Moreover, VEGF, which is highly expressed in solid tumors and further up-regulated by irradiation, has been shown to induce survivin expression in both tumor cells and vascular endothelial cells. Thus provide a survival signal to these cells and induce radioresistance to the subsequent irradiation exposure. Knocking down the expression of survivin by RNA interference or transfecting with a gene coding for a dominant negative survivin has been proved to be efficient in enhancing tumor cell radiosensitivity and improving tumor response to radiotherapy. The development of protein transduction technology made it possible to deliver large molecules into mammalian cells. We postulate that dominant negative mutants of survivin could fuse with protein transduction domain and the fusion proteins could cross cellular membranes and generate their biological activity to serve as tumor radiosensilizers. If the hypothesis proved to be practical, it would provide us an alternate method to enhance tumor radiosensitivity and the fusion proteins would be widely applicated in clinical settings because they were safer than gene therapy.
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Proteínas Associadas aos Microtúbulos/antagonistas & inibidores , Proteínas Associadas aos Microtúbulos/genética , Modelos Biológicos , Neoplasias/radioterapia , Tolerância a Radiação , Terapia Genética , Vetores Genéticos , Humanos , Interferência de RNA , TransfecçãoRESUMO
Hypoxia is a common phenomenon in human solid tumors and has been considered as an important, independent negative prognostic factor for response to treatment and survival of tumor patients. Hypoxia-inducible factor-1 (HIF-1) is the central transcription factor which is activated by hypoxia and modulates the expression of many genes involved in cell metabolism, proliferation, apoptosis, angiogenesis. Recently, it has been reported that HIF-1 contributes to tumor radioresistance by upregulating survivin expression under hypoxic conditions. Moreover, in hypoxic tumor cells, HIF-1 dependent signal transduction pathway is activated and could be further enhanced by radiation, thereby providing survival signals to adjacent vascular endothelial cells by upregulation of VEGF and bFGF and resulting in tumor radioresistance through vascular radioprotection. Recent research revealed that the stability of HIF-1alpha, one of the two subunits of HIF-1, determines the whole HIF-1 activity and the C-terminal transactivation domain of HIF-1alpha could reduce HIF-1 activity when overexpressed in tumor cells by disruption of the assembly of HIF-1 transcription complex. Therefore, we postulate that fusion with protein transduction domains would overcome the inability of C-terminal transactivation domain of HIF-1alpha to cross cellular membrane. Thus the recombinant fusion proteins could serve as cell-permeable HIF-1 antagonists, function as both inhibitors of tumor angiogenesis and tumor radiosensitizers, and would be widely used in clinical settings to improve tumor response to radiotherapy.
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Antineoplásicos/administração & dosagem , Fator 1 Induzível por Hipóxia/antagonistas & inibidores , Fator 1 Induzível por Hipóxia/metabolismo , Neoplasias/metabolismo , Neoplasias/radioterapia , Radiossensibilizantes/administração & dosagem , Hipóxia Celular/efeitos dos fármacos , Hipóxia Celular/efeitos da radiação , Permeabilidade da Membrana Celular , Humanos , Modelos Biológicos , Neoplasias/tratamento farmacológicoRESUMO
Hematopoietic stem cells transplantation has been wildly used in clinical settings and has shown exciting results in treating a wide variety of diseases. However, the relative small number of hematopoietic stem cells in bone marrow, even lower in peripheral or umbilical cord blood limits its clinical utility. There are several protocols, which have been developed to expand hematopoietic stem cells to reach clinical goal. With the recent insights into the mechanisms of hematopoietic stem cells self-renewal, we postulate that Cdx4, which is coded by one of the caudal related homeobox genes and regulates the expression of hox genes, could fuse with protein transduction domains, thereby get the ability to cross cellular membrane. And the recombinant fusion proteins could be used in expanding hematopoietic stem cells. Meanwhile, Cdx4 fusion proteins would be more efficient than other methods that had been developed for it can up-regulate a cocktail of hox genes, which has been proved to be capable of amplifying hematopoietic stem cells. It would provide us an alternative protocol to amplify hematopoietic stem cells if the hypothesis proved to be practical.
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Hematopoese/genética , Células-Tronco Hematopoéticas/metabolismo , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/metabolismo , Modelos Biológicos , Animais , Técnicas de Transferência de Genes , Genes Homeobox , Células-Tronco Hematopoéticas/citologia , Camundongos , Proteínas Recombinantes de Fusão/metabolismo , Transdução GenéticaRESUMO
Skin grafts, including skin flaps, are widely used in plastic and reconstructive surgery to cover wounds and tissue defects resulting from mechanic or burn injury. Ischemic necrosis is the main complication in skin graft surgery due to inefficient revascularization. Though the surgical delay procedure has been proved to be the only effective technique to prevent skin flap ischemic necrosis by mechanism of inducing adaption to hypoxia, but it is time consuming, costly, and having high risk of infection due to repeated surgery. Recent research demonstrated that, in addition to protecting cells against apoptosis, the expression of survivin correlates with intratumoral microvessel density in several different types of tumors and survivin could upregulate several proangiogenic factors, including VEGF, Egr-1 and Siah-1. Moreover, Survivin DeltaEx3, one of the survivin alternative splice variants, is necessary for activating the small GTPase Rac1 during endothelial tube formation and required for in vivo endothelial cell invasion. Therefore, we postulate that intracellular delivery of survivin or Survivin DeltaEx3 by fusion with protein transduction domain would enhance skin flap survival through accelerating revascularization by both inhibiting the apoptosis of microvascular endothelial cells and promoting skin flap angiogenesis. If the hypothesis was proved to be practical, the fusion proteins would be widely used in plastic and reconstructive surgery to prevent skin flap from ischemic necrosis in the future.
Assuntos
Permeabilidade da Membrana Celular/fisiologia , Sobrevivência de Enxerto , Proteínas Associadas aos Microtúbulos/fisiologia , Proteínas de Neoplasias/fisiologia , Transplante de Pele/fisiologia , Retalhos Cirúrgicos , Humanos , Proteínas Inibidoras de Apoptose , Modelos Biológicos , Neovascularização Fisiológica , Pele/irrigação sanguínea , SurvivinaRESUMO
OBJECTIVE: To investigate the role of nicotinamide adenine dinucleotide phosphate 4 (NADPH4,NOX4) and transforming growth factor-beta (TGF-ß) involve in pathogenesis of airway remodeling in chronic obstructive pulmonary disease (COPD). METHODS: Lung tissues from 36 COPD patients and 19 patients with normal lung function were enrolled in this study. The volume of airway smooth muscle (ASM)mass was evaluated. The expressions of NOX4, collagen â £ (Col â £) and TGF-ß were tested by a semi-quantitative morphological and/or immunohistochemistry staining method and Western blot, and their correlations with pulmonary functions were analyzed. RESULTS: â Index of the percentage of the thickness of ASM/external diameter of small airway (WT%) and the percentage of the area of ASM/transverse area of small airway (WA%) were significantly higher in the COPD group than those in controls(P<0.05).â¡In COPD patients,epithelial cells metaplasia were found and α-SMA and Col â £were expressed in a part of epithelial cells. The expressions of α-small muscle actin (α-SMA) and Col â were increased in COPD patients in comparison with the patients without obstructive airway disorders(P<0.05).â¢The expression of NOX4 in ASM and epithelial cells of COPD patients was significantly higher in comparison with the patients without COPD. The expression of NOX4 in ASM of small airway were statistically different among different COPD grade (P<0.05). Correlation analysis demonstrated that the level of NOX4 protein in ASM of small airway was inversely associated with pulmonary functions. â£The expression of TGF-ß in COPD was significantly higher than that in patients without COPD. ⤠Correlation analysis demonstrated that the level of NOX4 protein in ASM of small airway, WT% and WA% were inversely associated with pulmonary functions. CONCLUSIONS: â The airway remodeling of COPD is characterized by increasing hyperplasia of small airway smooth muscle.â¡Remodeling of airway smooth muscle associats with severity of airflow limitation in COPD patients. â¢The expressions of NOX4, TGF-ß and α-SMA in COPD epithelial cells and small airway smooth muscle cells are significantly enhanced. The expressions of NOX4, α-SMA and TGF-ß are positively correlated with the severity of chronic obstructive pulmonary air flow, suggesting that TGF-ß and NOX4 signaling may be involved in the development of chronic obstructive pulmonary disease airway remodeling.