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1.
Radiology ; 306(1): 172-182, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36098642

RESUMO

Background Approximately 40% of pancreatic tumors smaller than 2 cm are missed at abdominal CT. Purpose To develop and to validate a deep learning (DL)-based tool able to detect pancreatic cancer at CT. Materials and Methods Retrospectively collected contrast-enhanced CT studies in patients diagnosed with pancreatic cancer between January 2006 and July 2018 were compared with CT studies of individuals with a normal pancreas (control group) obtained between January 2004 and December 2019. An end-to-end tool comprising a segmentation convolutional neural network (CNN) and a classifier ensembling five CNNs was developed and validated in the internal test set and a nationwide real-world validation set. The sensitivities of the computer-aided detection (CAD) tool and radiologist interpretation were compared using the McNemar test. Results A total of 546 patients with pancreatic cancer (mean age, 65 years ± 12 [SD], 297 men) and 733 control subjects were randomly divided into training, validation, and test sets. In the internal test set, the DL tool achieved 89.9% (98 of 109; 95% CI: 82.7, 94.9) sensitivity and 95.9% (141 of 147; 95% CI: 91.3, 98.5) specificity (area under the receiver operating characteristic curve [AUC], 0.96; 95% CI: 0.94, 0.99), without a significant difference (P = .11) in sensitivity compared with the original radiologist report (96.1% [98 of 102]; 95% CI: 90.3, 98.9). In a test set of 1473 real-world CT studies (669 malignant, 804 control) from institutions throughout Taiwan, the DL tool distinguished between CT malignant and control studies with 89.7% (600 of 669; 95% CI: 87.1, 91.9) sensitivity and 92.8% specificity (746 of 804; 95% CI: 90.8, 94.5) (AUC, 0.95; 95% CI: 0.94, 0.96), with 74.7% (68 of 91; 95% CI: 64.5, 83.3) sensitivity for malignancies smaller than 2 cm. Conclusion The deep learning-based tool enabled accurate detection of pancreatic cancer on CT scans, with reasonable sensitivity for tumors smaller than 2 cm. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Aisen and Rodrigues in this issue.


Assuntos
Aprendizado Profundo , Neoplasias Pancreáticas , Masculino , Humanos , Idoso , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodos , Pâncreas
2.
BMC Cancer ; 23(1): 58, 2023 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-36650440

RESUMO

BACKGROUND: CT is the major detection tool for pancreatic cancer (PC). However, approximately 40% of PCs < 2 cm are missed on CT, underscoring a pressing need for tools to supplement radiologist interpretation. METHODS: Contrast-enhanced CT studies of 546 patients with pancreatic adenocarcinoma diagnosed by histology/cytology between January 2005 and December 2019 and 733 CT studies of controls with normal pancreas obtained between the same period in a tertiary referral center were retrospectively collected for developing an automatic end-to-end computer-aided detection (CAD) tool for PC using two-dimensional (2D) and three-dimensional (3D) radiomic analysis with machine learning. The CAD tool was tested in a nationwide dataset comprising 1,477 CT studies (671 PCs, 806 controls) obtained from institutions throughout Taiwan. RESULTS: The CAD tool achieved 0.918 (95% CI, 0.895-0.938) sensitivity and 0.822 (95% CI, 0.794-0.848) specificity in differentiating between studies with and without PC (area under curve 0.947, 95% CI, 0.936-0.958), with 0.707 (95% CI, 0.602-0.797) sensitivity for tumors < 2 cm. The positive and negative likelihood ratios of PC were 5.17 (95% CI, 4.45-6.01) and 0.10 (95% CI, 0.08-0.13), respectively. Where high specificity is needed, using 2D and 3D analyses in series yielded 0.952 (95% CI, 0.934-0.965) specificity with a sensitivity of 0.742 (95% CI, 0.707-0.775), whereas using 2D and 3D analyses in parallel to maximize sensitivity yielded 0.915 (95% CI, 0.891-0.935) sensitivity at a specificity of 0.791 (95% CI, 0.762-0.819). CONCLUSIONS: The high accuracy and robustness of the CAD tool supported its potential for enhancing the detection of PC.


Assuntos
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico por imagem , Estudos Retrospectivos , Adenocarcinoma/diagnóstico por imagem , Taiwan/epidemiologia , Sensibilidade e Especificidade , Neoplasias Pancreáticas
3.
J Cell Physiol ; 236(5): 3979-3990, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33251599

RESUMO

Prostate cancer has high metastatic potential. Men with higher urinary levels of the sleep hormone melatonin are much less likely to develop advanced prostate cancer compared with men with lower levels of melatonin. Melatonin has shown anticancer activity in experimental investigations. Nevertheless, the therapeutic effect of melatonin in metastatic prostate cancer has largely remained a mystery. Analyses of Gene Expression Omnibus data and human tissue samples indicated that levels of matrix metallopeptidase 13 (MMP-13) expression are higher in prostate cancer patients than in healthy cancer-free individuals. Mechanistic investigations revealed that melatonin inhibits MMP-13 expression and the migratory and invasive capacities of prostate cancer cells via the MT1 receptor and the phospholipase C, p38, and c-Jun signaling cascades. Importantly, tumor growth rate and metastasis to distant organs were suppressed by melatonin in an orthotopic prostate cancer model. This is the first demonstration showing that melatonin impedes metastasis of prostate cancer by suppressing MMP-13 expression in both in vitro and in vivo models. Thus, melatonin is promising in the management of prostate cancer metastasis and deserves to undergo clinical investigations.


Assuntos
Metaloproteinase 13 da Matriz/metabolismo , Melatonina/farmacologia , Neoplasias da Próstata/enzimologia , Neoplasias da Próstata/patologia , Animais , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação para Baixo/efeitos dos fármacos , Humanos , Masculino , Camundongos SCID , Modelos Biológicos , Invasividade Neoplásica , Metástase Neoplásica , Proteínas Proto-Oncogênicas c-jun/metabolismo , Receptores de Melatonina/metabolismo , Fosfolipases Tipo C/metabolismo , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
4.
Int J Mol Sci ; 22(6)2021 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-33805784

RESUMO

Hepatocellular carcinoma (HCC) frequently shows early invasion into blood vessels as well as intrahepatic metastasis. Innovations of novel small-molecule agents to block HCC invasion and subsequent metastasis are urgently needed. Moscatilin is a bibenzyl derivative extracted from the stems of a traditional Chinese medicine, orchid Dendrobium loddigesii. Although moscatilin has been reported to suppress tumor angiogenesis and growth, the anti-metastatic property of moscatilin has not been elucidated. The present results revealed that moscatilin inhibited metastatic behavior of HCC cells without cytotoxic fashion in highly invasive human HCC cell lines. Furthermore, moscatilin significantly suppressed the activity of urokinase plasminogen activator (uPA), but not matrix metalloproteinase (MMP)-2 and MMP-9. Interestingly, moscatilin-suppressed uPA activity was through down-regulation the protein level of uPA, and did not impair the uPA receptor and uPA inhibitory molecule (PAI-1) expressions. Meanwhile, the mRNA expression of uPA was inhibited via moscatilin in a concentration-dependent manner. In addition, the expression of phosphorylated Akt, rather than ERK1/2, was inhibited by moscatilin treatment. The expression of phosphor-IκBα, and -p65, as well as κB-luciferase activity were also repressed after moscatilin treatment. Transfection of constitutively active Akt (Myr-Akt) obviously restored the moscatilin-inhibited the activation of NF-κB and uPA, and cancer invasion in HCC cells. Taken together, these results suggest that moscatilin impedes HCC invasion and uPA expression through the Akt/NF-κB signaling pathway. Moscatilin might serve as a potential anti-metastatic agent against the disease progression of human HCC.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Compostos de Benzil/farmacologia , Movimento Celular/efeitos dos fármacos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , Ativador de Plasminogênio Tipo Uroquinase/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Embrião de Galinha , Membrana Corioalantoide/irrigação sanguínea , Membrana Corioalantoide/efeitos dos fármacos , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , Regulação Neoplásica da Expressão Gênica , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , NF-kappa B/antagonistas & inibidores , NF-kappa B/metabolismo , Neovascularização Patológica/genética , Neovascularização Patológica/metabolismo , Neovascularização Patológica/prevenção & controle , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Quinases S6 Ribossômicas 70-kDa/genética , Proteínas Quinases S6 Ribossômicas 70-kDa/metabolismo , Transdução de Sinais , Serina-Treonina Quinases TOR/genética , Serina-Treonina Quinases TOR/metabolismo , Ativador de Plasminogênio Tipo Uroquinase/antagonistas & inibidores , Ativador de Plasminogênio Tipo Uroquinase/metabolismo
5.
Mol Plant Microbe Interact ; 31(12): 1257-1270, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-29877166

RESUMO

Plant viruses cause devastating diseases in plants, yet no effective viricide is available for agricultural application. We screened cultured filtrates derived from various soil microorganisms cultured in vegetable broth that enhanced plant viral resistance. A cultured filtrate, designated F8 culture filtrate, derived from a fungus belonging to the genus Trichosporon, induced strong resistance to various viruses on different plants. Our inoculation assay found the infection rate of Tobacco mosaic virus (TMV)-inoculated Nicotiana benthamiana with F8 culture filtrate pretreatment may decrease to 0%, whereas salicylic acid (SA)-pretreated N. benthamiana attenuated TMV-caused symptoms but remained 100% infected. Tracking Tobacco mosaic virus tagged with green fluorescence protein in plants revealed pretreatment with F8 culture filtrate affected the initial establishment of the virus infection. From F8 culture filtrate, we identified a previously unknown polysaccharide composed of D-mannose, D-galactose, and D-glucose in the ratio 1.0:1.2:10.0 with a α-D-1,4-glucan linkage to be responsible for the induction of plant resistance against viruses through priming of SA-governed immune-responsive genes. Notably, F8 culture filtrate only triggered local defense but was much more effective than conventional SA-mediated systematic acquired resistance. Our finding revealed that microbial cultured metabolites provided a rich source for identification of potent elicitors in plant defense.


Assuntos
Nicotiana/imunologia , Doenças das Plantas/imunologia , Imunidade Vegetal/efeitos dos fármacos , Polissacarídeos/farmacologia , Vírus do Mosaico do Tabaco/fisiologia , Trichosporon/metabolismo , Genes Reporter , Filogenia , Doenças das Plantas/virologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/imunologia , Folhas de Planta/virologia , Polissacarídeos/química , Polissacarídeos/imunologia , Ácido Salicílico/metabolismo , Ácido Salicílico/farmacologia , Plântula/efeitos dos fármacos , Plântula/imunologia , Plântula/virologia , Microbiologia do Solo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Nicotiana/efeitos dos fármacos , Nicotiana/virologia , Trichosporon/citologia , Trichosporon/genética , Trichosporon/isolamento & purificação
6.
Biochem Biophys Res Commun ; 477(4): 794-800, 2016 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-27369071

RESUMO

Helicobacter pylori is a notorious human pathogen and the appearance of antibiotic resistance of this bacterium has posed a serious threat to human health. Lipopolysaccharide (LPS) is a key virulence factor and plays important roles in pathogenesis of H. pylori infection. Sedoheptulose 7-phosphate isomerase (GmhA), as an enzyme participating in the first step of heptose biosynthesis, is indispensable for the formation of inner core oligosaccharide of LPS. In this study, we cloned one putative gmhA ortholog, hp0857, from H. pylori 26695 and overexpressed it in Eschericha coli. Based on the results of molecular weight determination, the recombinant HP0857 is likely a homodimer. Analysis of enzymatic kinetic properties of this protein confirmed that hp0857 is indeed encoded a phosphoheptose isomerase which can utilize sedoheptulose 7-phosphate as the substrate in the ADP-L-glycero-D-manno-heptose (ADP- L,D-Hep) biosynthesis pathway. We also generated an HP0857 knockout mutant and explored its phenotypic changes. This mutant exhibited a decreased growth rate and displayed a "deep rough" type of LPS structure. In addition, it also had a slight decrease in its motility and was more susceptible to hydrophobic antibiotic novobiocin and detergents Triton X-100 and SDS. Furthermore, the adhesive capacity of the HP0857 knockout mutant to AGS cells was reduced significantly, and most of the infected cells didn't show a classic hummingbird phenotype. However, complementation of the HP0857 knockout mutation restored most of these phenotypic changes. In conclusion, we demonstrated that HP0857 protein is essential for inner core biosynthesis of H. pylori LPS and is a potential target for developing new antimicrobial agents against H. pylori infection.


Assuntos
Aldose-Cetose Isomerases/metabolismo , Adesão Celular/fisiologia , Proteínas de Escherichia coli/metabolismo , Helicobacter pylori/metabolismo , Lipopolissacarídeos/biossíntese , Racemases e Epimerases/metabolismo , Fosfatos Açúcares/metabolismo , Helicobacter pylori/classificação , Especificidade da Espécie
7.
Biomedicines ; 10(1)2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-35052824

RESUMO

Helicobacter pylori infection is associated with several gastric diseases, including gastritis, peptic ulcer, gastric adenocarcinoma and mucosa-associated lymphatic tissue (MALT) lymphoma. Due to the prevalence and severeness of H. pylori infection, a thorough understanding of this pathogen is necessary. Lipopolysaccharide, one of the major virulence factors of H. pylori, can exert immunomodulating and immunostimulating functions on the host. In this study, the HP0044 and HP1275 genes were under investigation. These two genes potentially encode GDP-D-mannose dehydratase (GMD) and phosphomannomutase (PMM)/phosphoglucomutase (PGM), respectively, and are involved in the biosynthesis of fucose. HP0044 and HP1275 knockout mutants were generated; both mutants displayed a truncated LPS, suggesting that the encoded enzymes are not only involved in fucose production but are also important for LPS construction. In addition, these two gene knockout mutants exhibited retarded growth, increased surface hydrophobicity and autoaggregation as well as being more sensitive to the detergent SDS and the antibiotic novobiocin. Furthermore, the LPS-defective mutants also had significantly reduced bacterial infection, adhesion and internalization in the in vitro cell line model. Moreover, disruptions of the HP0044 and HP1275 genes in H. pylori altered protein sorting into outer membrane vesicles. The critical roles of HP0044 and HP1275 in LPS biosynthesis, bacterial fitness and pathogenesis make them attractive candidates for drug inventions against H. pylori infection.

8.
Int Arch Occup Environ Health ; 84(1): 91-103, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20431893

RESUMO

OBJECTIVES: Microelectronic engineers are considered valuable human capital contributing significantly toward economic development, but they may encounter stressful work conditions in the context of a globalized industry. The study aims at identifying risk factors of depressive disorders primarily based on job stress models, the Demand-Control-Support and Effort-Reward Imbalance models, and at evaluating whether depressive disorders impair work performance in microelectronics engineers in Taiwan. METHODS: The case-control study was conducted among 678 microelectronics engineers, 452 controls and 226 cases with depressive disorders which were defined by a score 17 or more on the Beck Depression Inventory and a psychiatrist's diagnosis. The self-administered questionnaires included the Job Content Questionnaire, Effort-Reward Imbalance Questionnaire, demography, psychosocial factors, health behaviors and work performance. Hierarchical logistic regression was applied to identify risk factors of depressive disorders. Multivariate linear regressions were used to determine factors affecting work performance. RESULTS: By hierarchical logistic regression, risk factors of depressive disorders are high demands, low work social support, high effort/reward ratio and low frequency of physical exercise. Combining the two job stress models may have better predictive power for depressive disorders than adopting either model alone. Three multivariate linear regressions provide similar results indicating that depressive disorders are associated with impaired work performance in terms of absence, role limitation and social functioning limitation. CONCLUSIONS: The results may provide insight into the applicability of job stress models in a globalized high-tech industry considerably focused in non-Western countries, and the design of workplace preventive strategies for depressive disorders in Asian electronics engineering population.


Assuntos
Transtorno Depressivo/epidemiologia , Engenharia , Indústrias , Sistemas Microeletromecânicos , Exposição Ocupacional/efeitos adversos , Adulto , Transtorno Depressivo/diagnóstico , Transtorno Depressivo/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Inquéritos e Questionários , Taiwan/epidemiologia , Adulto Jovem
9.
Virulence ; 12(1): 1610-1628, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34125649

RESUMO

Helicobacter pylori infection is linked to serious gastric-related diseases including gastric cancer. However, current therapies for treating H. pylori infection are challenged by the increased antibiotic resistance of H. pylori. Therefore, it is in an urgent need to identify novel targets for drug development against H. pylori infection. In this study, HP0860 gene from H. pylori predicted to encode a D-glycero-D-manno-heptose-1,7-bisphosphate phosphatase (GmhB) involved in the synthesis of ADP-L-glycero-D-manno-heptose for the assembly of lipopolysaccharide (LPS) in the inner core region was cloned and characterized. We reported HP0860 protein is monomeric and functions as a phosphatase by converting D-glycero-D-manno-heptose-1,7-bisphosphate into D-glycero-D-manno-heptose-1-phosphate with a preference for the ß-anomer over the α-anomer of sugar phosphate substrates. Subsequently, a HP0860 knockout mutant and its complementary mutant were constructed and their phenotypic properties were examined. HP0860 knockout mutant contained both mature and immature forms of LPS and could still induce significant IL-8 secretion after gastric AGS cell infection, suggesting other enzymatic activities in HP0860 knockout mutant might be able to partially compensate for the loss of HP0860 activity. In addition, HP0860 knockout mutant was much more sensitive to antibiotic novobiocin, had decreased adherence abilities, and caused less classic hummingbird phenotype on the infected AGS cells, indicating H. pylori lacking HP0860 is less virulent. Furthermore, the disruption of HP0860 gene altered the sorting of cargo proteins into outer membrane vesicles (OMVs). The above findings confirm the importance of HP0860 in LPS core biosynthesis and shed light on therapeutic intervention against H. pylori infection.


Assuntos
Helicobacter pylori , Heptoses/biossíntese , Monoéster Fosfórico Hidrolases/metabolismo , Virulência , Difosfato de Adenosina , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Inativação de Genes , Infecções por Helicobacter , Helicobacter pylori/enzimologia , Helicobacter pylori/genética , Humanos , Lipopolissacarídeos/biossíntese , Monoéster Fosfórico Hidrolases/genética
10.
Res Sq ; 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-33442676

RESUMO

'Federated Learning' (FL) is a method to train Artificial Intelligence (AI) models with data from multiple sources while maintaining anonymity of the data thus removing many barriers to data sharing. During the SARS-COV-2 pandemic, 20 institutes collaborated on a healthcare FL study to predict future oxygen requirements of infected patients using inputs of vital signs, laboratory data, and chest x-rays, constituting the "EXAM" (EMR CXR AI Model) model. EXAM achieved an average Area Under the Curve (AUC) of over 0.92, an average improvement of 16%, and a 38% increase in generalisability over local models. The FL paradigm was successfully applied to facilitate a rapid data science collaboration without data exchange, resulting in a model that generalised across heterogeneous, unharmonized datasets. This provided the broader healthcare community with a validated model to respond to COVID-19 challenges, as well as set the stage for broader use of FL in healthcare.

11.
Nat Med ; 27(10): 1735-1743, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34526699

RESUMO

Federated learning (FL) is a method used for training artificial intelligence models with data from multiple sources while maintaining data anonymity, thus removing many barriers to data sharing. Here we used data from 20 institutes across the globe to train a FL model, called EXAM (electronic medical record (EMR) chest X-ray AI model), that predicts the future oxygen requirements of symptomatic patients with COVID-19 using inputs of vital signs, laboratory data and chest X-rays. EXAM achieved an average area under the curve (AUC) >0.92 for predicting outcomes at 24 and 72 h from the time of initial presentation to the emergency room, and it provided 16% improvement in average AUC measured across all participating sites and an average increase in generalizability of 38% when compared with models trained at a single site using that site's data. For prediction of mechanical ventilation treatment or death at 24 h at the largest independent test site, EXAM achieved a sensitivity of 0.950 and specificity of 0.882. In this study, FL facilitated rapid data science collaboration without data exchange and generated a model that generalized across heterogeneous, unharmonized datasets for prediction of clinical outcomes in patients with COVID-19, setting the stage for the broader use of FL in healthcare.


Assuntos
COVID-19/fisiopatologia , Aprendizado de Máquina , Avaliação de Resultados em Cuidados de Saúde , COVID-19/terapia , COVID-19/virologia , Registros Eletrônicos de Saúde , Humanos , Prognóstico , SARS-CoV-2/isolamento & purificação
12.
Stem Cell Res ; 49: 102029, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33096384

RESUMO

Type 1 diabetes (T1D) is characterized by the autoimmune destruction of insulin-producing ß cells. Genetic studies have identified > 60 T1D risk loci that harbor genes with disease-causative alleles. However, determining the biological effects of such loci is often difficult due to limited tissue availability. Disease-specific human induced pluripotent stem cells (hiPSCs) are a valuable resource for modeling T1D pathogenesis. In particular, families with complete disease penetrance offer an opportunity to further dissect T1D risk loci. Here, we describe the generation of three hiPSC lines from a T1D family with sequence variants associated with autoimmunity.


Assuntos
Diabetes Mellitus Tipo 1 , Células-Tronco Pluripotentes Induzidas , Células Secretoras de Insulina , Alelos , Autoimunidade/genética , Diabetes Mellitus Tipo 1/genética , Humanos
13.
PeerJ ; 6: e4248, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29340247

RESUMO

AIM: To perform a systematic review and meta-analysis of the weekend effect on the mortality of patients with upper gastrointestinal bleeding(UGIB). METHODS: The review protocol has been registered in the PROSPERO International Prospective Register of Systematic Reviews (registration number: CRD42017073313) and was written according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. We conducted a search of the PUBMED, COCHRANE, EMBASE and CINAHL databases from inception to August 2017. All observational studies comparing mortality between UGIB patients with weekend versus weekday admissions were included. Articles that were published only in abstract form or not published in a peer-reviewed journal were excluded. The quality of articles was assessed using the Newcastle-Ottawa Scale. We pooled results from the articles using random-effect models. Heterogeneity was evaluated by the chi-square-based Q-test and I2 test. To address heterogeneity, we performed sensitivity and subgroup analyses. Potential publication bias was assessed via funnel plot. RESULTS: Eighteen observational cohort studies involving 1,232,083 study patients were included. Weekend admission was associated with significantly higher 30-day or in-hospital mortality in all studies (OR = 1.12, 95% CI [1.07-1.17], P < 0.00001). Increased in-hospital mortality was also associated with weekend admission (OR = 1.12, 95% CI [1.08-1.17], P < 0.00001). No significant difference in in-hospital mortality was observed between patients admitted with variceal bleeding during the weekend or on weekdays (OR = 0.99, 95% CI [0.91-1.08], P = 0.82); however, weekend admission was associated with a 15% increase in in-hospital mortality for patients with non-variceal bleeding (OR = 1.15, 95% CI [1.09-1.21], P < 0.00001). The time to endoscopy for weekday admission was significantly less than that obtained for weekend admission (MD = -2.50, 95% CI [-4.08--0.92], P = 0.002). CONCLUSIONS: The weekend effect is associated with increased mortality of UGIB patients, particularly in non-variceal bleeding. The timing of endoscopic intervention might be a factor that influences mortality of UGIB patients.

14.
Cell Death Dis ; 8(8): e2964, 2017 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-28771226

RESUMO

Chondrosarcoma is the second most common primary malignancy of bone, and one of the most difficult bone tumors to diagnose and treat. It is well known that increased levels of vascular endothelial growth factor-C (VEGF-C) promote active tumor lymphangiogenesis and lymphatic tumor spread to regional lymph nodes. Brain-derived neurotrophic factor (BDNF) is known to promote metastasis in human chondrosarcoma cells. Knowing more about the mechanism of BDNF in VEGF-C expression and lymphangiogenesis in human chondrosarcoma would improve our understanding as how to prevent chondrosarcoma angiogenesis and metastasis, which currently lacks effective adjuvant treatment. Here, we found that BDNF expression was at least 2.5-fold higher in the highly migratory JJ012(S10) cell line as compared with the primordial cell line (JJ012). In addition, VEGF-C expression and secretion was markedly increased in JJ012(S10) cells. Conditioned medium from JJ012(S10) cells significantly promoted migration and tube formation of human lymphatic endothelial cells (LECs), whereas knockdown of BDNF attenuated LEC migration and tube formation by suppressing VEGF-C production in JJ012(S10) cells. Mechanistic investigations indicated that BDNF facilitated VEGF-C-dependent lymphangiogenesis through the MEK/ERK/mTOR signaling pathway. We also showed that microRNA (miR)-624-3p expression was negatively regulated by BDNF via the MEK/ERK/mTOR cascade. Importantly, BDNF knockdown profoundly inhibited tumor-associated lymphangiogenesis in vivo. Further analyses identified that BDNF promoted tumor lymphangiogenesis by downregulating miR-624-3p in human chondrosarcoma tissues. In conclusion, this study is the first to reveal the mechanism underlying BDNF-induced lymphangiogenesis. We suggest that BDNF may serve as a promising therapeutic target for the restriction of VEGF-C-mediated tumor lymphangiogenesis and lymphatic metastasis.


Assuntos
Neoplasias Ósseas/metabolismo , Fator Neurotrófico Derivado do Encéfalo/farmacologia , Condrossarcoma/metabolismo , Linfangiogênese/efeitos dos fármacos , MicroRNAs/biossíntese , Proteínas de Neoplasias/biossíntese , RNA Neoplásico/biossíntese , Fator C de Crescimento do Endotélio Vascular/biossíntese , Adulto , Neoplasias Ósseas/genética , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Condrossarcoma/genética , Condrossarcoma/patologia , Feminino , Humanos , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Proteínas de Neoplasias/genética , RNA Neoplásico/genética
15.
Cancer Lett ; 388: 249-261, 2017 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-27965041

RESUMO

Pancreatic cancer is an aggressive malignancy, which generally responds poorly to chemotherapy. In this study, trichodermin, an endophytic fungal metabolite from Nalanthamala psidii, was identified as a potent and selective antitumor agent in human pancreatic cancer. Trichodermin exhibited antiproliferative effects against pancreatic cancer cells, especially p53-mutated cells (MIA PaCa-2 and BxPC-3) rather than normal pancreatic epithelial cells. We found that trichodermin induced caspase-dependent and mitochondrial intrinsic apoptosis. Trichodermin also increased apoptosis through mitotic arrest by activating Cdc2/cyclin B1 complex activity. Moreover, trichodermin promoted the activation of c-Jun N-terminal kinase (JNK), and inhibition of JNK by its inhibitor, shRNA, or siRNA significantly reversed trichodermin-mediated caspase-dependent apoptosis. Trichodermin triggered DNA damage stress to activate p53 function for executing apoptosis in p53-mutated cells. Importantly, we demonstrated that trichodermin with efficacy similar to gemcitabine, profoundly suppressed tumor growth through inducing intratumoral DNA damage and JNK activation in orthotopic pancreatic cancer model. Based on these findings, trichodermin is a potential therapeutic agent worthy of further development into a clinical trial candidate for treating cancer, especially the mutant p53 pancreatic cancer.


Assuntos
Proteínas Quinases JNK Ativadas por Mitógeno/antagonistas & inibidores , Neoplasias Pancreáticas/genética , Tricodermina/metabolismo , Animais , Apoptose , Linhagem Celular Tumoral , Dano ao DNA , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Masculino , Camundongos , Camundongos SCID , Mitose , Neoplasias Pancreáticas/patologia , Transdução de Sinais , Proteína Supressora de Tumor p53/metabolismo
16.
Cell Death Dis ; 8(4): e2750, 2017 04 13.
Artigo em Inglês | MEDLINE | ID: mdl-28406476

RESUMO

In recent years, much research has focused on the role of angiogenesis in osteosarcoma, which occurs predominantly in adolescents and young adults. The vascular endothelial growth factor-A (VEGF-A) pathway is the key regulator of angiogenesis and in osteosarcoma. VEGF-A expression has been recognized as a prognostic marker in angiogenesis. Aberrant WNT1-inducible signaling pathway protein-1 (WISP-1) expression is associated with various cancers. However, the function of WISP-1 in osteosarcoma angiogenesis is poorly understood. We demonstrate a positive correlation between WISP-1 and VEGF-A expression in human osteosarcoma. Moreover, we show that WISP-1 promotes VEGF-A expression in human osteosarcoma cells, subsequently inducing human endothelial progenitor cell (EPC) migration and tube formation. The focal adhesion kinase (FAK), Jun amino-terminal kinase (JNK), and hypoxia-inducible factor (HIF)-1α signaling pathways were activated after WISP-1 stimulation, while FAK, JNK, and HIF-1α inhibitors or small interfering RNA (siRNA) abolished WISP-1-induced VEGF-A expression and angiogenesis. In vitro and in vivo studies revealed down-regulation of microRNA-381 (miR-381) in WISP-1-induced VEGF-A expression and angiogenesis. Our findings reveal that WISP-1 enhances VEGF-A expression and angiogenesis through the FAK/JNK/HIF-1α signaling pathways, as well as via down-regulation of miR-381 expression. WISP-1 may be a promising target in osteosarcoma angiogenesis.


Assuntos
Neoplasias Ósseas , Proteínas de Sinalização Intercelular CCN/metabolismo , Regulação Neoplásica da Expressão Gênica , Neovascularização Patológica , Osteossarcoma , Proteínas Proto-Oncogênicas/metabolismo , Fator A de Crescimento do Endotélio Vascular/biossíntese , Adolescente , Adulto , Animais , Neoplasias Ósseas/irrigação sanguínea , Neoplasias Ósseas/metabolismo , Neoplasias Ósseas/patologia , Linhagem Celular Tumoral , Embrião de Galinha , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Feminino , Humanos , Masculino , MicroRNAs/biossíntese , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Osteossarcoma/irrigação sanguínea , Osteossarcoma/metabolismo , Osteossarcoma/patologia , RNA Neoplásico/biossíntese , Transdução de Sinais , Células-Tronco/metabolismo , Células-Tronco/patologia
17.
World J Gastroenterol ; 11(2): 171-5, 2005 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-15633210

RESUMO

AIM: To investigate whether the changes of gap junction gene connexin messenger RNA in the noncancerous liver tissue of patients with hepatocellular carcinoma (HCC) could play a significant role in its postresection recurrence. METHODS: Seventy-nine consecutive patients having undergone curative resection for HCC entered this study. Using a reverse-transcription polymerase chain reaction (RT-PCR)-based assay, connexin (Cx) 26, connexin (Cx) 32 and connexin (Cx) 43 mRNAs were determined prospectively in noncancerous liver tissues from these 79 patients and in the liver tissues from 15 controls. The correlations between connexin mRNA expression and the clinicopathological variables and outcomes (tumor recurrence and recurrence related mortality) were studied. RESULTS: Compared with liver tissues of control patients, the expression of Cx 32 mRNA in noncancerous liver tissues was significantly lower (mean: 0.715 vs control 1.225, P<0.01), whereas the decreased Cx 26 mRNA (mean: 0.700 vs of control 1.205, P>0.05) and increased Cx 43 mRNA (mean: 0.241 vs control 0.100, P>0.05) had no statistical significance. We defined the value of Cx 32 mRNA or Cx 26 mRNA below 0.800 as a lower value. By multivariate analysis for noncancerous livers, a lower value of Cx 32 mRNA correlated significantly with a risk of HCC recurrence and recurrence-related mortality. The lower value of Cx 26 mRNA did not correlate with recurrence and mortality. The increased value of Cx43 mRNA also did not correlate with postoperative recurrence and recurrence-related mortality. By multivariate analysis, other significant predictors of HCC recurrence included vascular permeation, cellular dedifferentiation, and less encapsulation. The other significant parameter of recurrence related mortality was vascular permeation. CONCLUSION: The decreased expression of Cx 32 mRNA in noncancerous liver tissues plays a significant role in the prediction of postoperative recurrence of HCC.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/cirurgia , Conexinas/genética , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/cirurgia , RNA Mensageiro/genética , Sequência de Bases , Biomarcadores Tumorais , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Primers do DNA , Feminino , Junções Comunicantes/genética , Hemorragia , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Necrose , Recidiva , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sobrevida , Resultado do Tratamento
18.
World J Gastroenterol ; 11(2): 187-92, 2005 Jan 14.
Artigo em Inglês | MEDLINE | ID: mdl-15633213

RESUMO

AIM: To investigate the prognostic role of isoform 165 vascular endothelial growth factor messenger RNA (VEGF165 mRNA) in noncancerous liver tissues from patients with primary hepatocellular carcinoma (HCC). METHODS: Using a reverse-transcription polymerase chain reaction (RT-PCR)-based assay, VEGF mRNA was determined prospectively in noncancerous liver tissues from 60 consecutive patients with HCC undergoing curative resection. We categorized the patients with VEGF165 mRNA over 0.500 in noncancerous liver tissues as group A, and those below 0.500 as group B. RESULTS: Among the isoforms of VEGF mRNA by multivariate analysis, a higher level of VEGF165 mRNA in noncancerous liver tissue correlated significantly with a higher risk of HCC recurrence (P = 0.039) and recurrence-related mortality (P = 0.048), but VEGF121 did not. The other significant predictors of recurrence consisted of vascular permeation (P = 0.022), daughter nodules (P = 0.033), cellular dedifferentiation (P = 0.033), an absent or incomplete capsule (P = 0.037). A significant variable of recurrence-related mortality was vascular permeation (P = 0.012). As to the clinical manifestations of 16 patients who developed recurrence, the recurrent tumor number over 2, recurrent extent over two-liver segments, and the median survival after recurrence, all significantly correlated with group A patients (P = 0.043, 0.043, and 0.048, respectively). However, the presence of extrahepatic metastasis was not (P>0.05). The difference in recurrence after treatment between the two groups had no statistical significance (P>0.05). CONCLUSION: The higher expression of isoform VEGF165 mRNA in noncancerous liver remnant of patients with HCC may be a significant biological indicator of the invasiveness of postoperative recurrence.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Fígado/patologia , RNA Mensageiro/genética , Fator A de Crescimento do Endotélio Vascular/genética , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Feminino , Humanos , Cirrose Hepática/patologia , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Invasividade Neoplásica , Isoformas de Proteínas/genética , Recidiva
19.
Sci Rep ; 5: 9693, 2015 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-25892370

RESUMO

Graphene thin films have great potential to function as transparent electrodes in organic electronic devices, due to their excellent conductivity and high transparency. Recently, organic light-emitting diodes (OLEDs)have been successfully demonstrated to possess high luminous efficiencies with p-doped graphene anodes. However, reliable methods to fabricate n-doped graphene cathodes have been lacking, which would limit the application of graphene in flexible electronics. In this paper, we demonstrate fully solution-processed OLEDs with n-type doped multilayer graphene as the top electrode. The work function and sheet resistance of graphene are modified by an aqueous process which can also transfer graphene on organic devices as the top electrodes. With n-doped graphene layers used as the top cathode, all-solution processed transparent OLEDs can be fabricated without any vacuum process.

20.
World J Gastroenterol ; 10(19): 2785-90, 2004 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-15334670

RESUMO

AIM: To investigate the prognostic value of the expression of connexin (Cx) 26, 32 and 43 messenger RNA (mRNA) in hepatocellular carcinoma (HCC) tissues. METHODS: Using a reverse-transcriptase polymerase chain reaction (RT-PCR), Cx 26, Cx 32 and Cx 43 mRNAs were determined in the liver tissues of 15 controls and in HCC tissues of 25 patients undergoing curative hepatic resection. The patients were followed up clinically. RESULTS: Cx 26 and Cx 32 mRNAs were significantly lower in HCC tissues compared with controls (both P<0.01). By multivariate analysis, a lower level of Cx 26 and Cx 32 mRNA correlated significantly with a risk of HCC recurrence (P = 0.033) and recurrence-related mortality (P = 0.031, P = 0.031). Cx 43 mRNA was higher in HCC tissues compared with controls but did not correlate with postoperative recurrence or recurrence-related mortality. Other significant predictors of HCC recurrence included cellular dedifferentiation (P = 0.033), less encapsulation (P = 0.050), vascular permeation (P = 0.046), and daughter nodules (P = 0.046). Significant variables related to recurrence-related mortality consisted of cell dedifferentiation (P = 0.031), vascular permeation (P = 0.048), and daughter nodules (P = 0.048). The levels of Cx 26 and Cx 32 mRNAs correlated significantly with cell differentiation (P = 0.031). CONCLUSION: A low expression of Cx 26 and Cx 32 mRNAs in HCC tissues is predictive of postoperative recurrence of HCCs.


Assuntos
Carcinoma Hepatocelular/genética , Conexinas/genética , Neoplasias Hepáticas/genética , Sequência de Bases , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/cirurgia , Conexina 26 , Primers do DNA , Feminino , Junções Comunicantes/genética , Humanos , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/cirurgia , Masculino , Pessoa de Meia-Idade , Recidiva , Proteína beta-1 de Junções Comunicantes
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