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1.
New Phytol ; 243(2): 567-579, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38812270

RESUMO

Aerosols could significantly influence ecosystem carbon and water fluxes, potentially altering their interconnected dynamics, typically characterized by water-use efficiency (WUE). However, our understanding of the underlying ecophysiological mechanisms remains limited due to insufficient field observations. We conducted 4-yr measurements of leaf photosynthesis and transpiration, as well as 3-yr measurements of stem growth (SG) and sap flow of poplar trees exposed to natural aerosol fluctuation, to elucidate aerosol's impact on plant WUE. We found that aerosol improved sun leaf WUE mainly because a sharp decline in photosynthetically active radiation (PAR) inhibited its transpiration, while photosynthesis was less affected, as the negative effect induced by declined PAR was offset by the positive effect induced by low leaf vapor pressure deficit (VPDleaf). Conversely, diffuse radiation fertilization (DRF) effect stimulated shade leaf photosynthesis with minimal impact on transpiration, leading to an improved WUE. The responses were further verified by a strong DRF on SG and a decrease in sap flow due to the suppresses in total radiation and VPD. Our field observations indicate that, contrary to the commonly assumed coupling response, carbon uptake and water use exhibited dissimilar reactions to aerosol pollution, ultimately enhancing WUE at the leaf and canopy level.


Assuntos
Aerossóis , Carbono , Fotossíntese , Folhas de Planta , Transpiração Vegetal , Populus , Água , Água/metabolismo , Fotossíntese/efeitos da radiação , Fotossíntese/efeitos dos fármacos , Carbono/metabolismo , Folhas de Planta/fisiologia , Folhas de Planta/efeitos da radiação , Folhas de Planta/efeitos dos fármacos , Transpiração Vegetal/fisiologia , Transpiração Vegetal/efeitos da radiação , Populus/fisiologia , Populus/efeitos da radiação , Populus/efeitos dos fármacos , Caules de Planta/efeitos da radiação , Caules de Planta/efeitos dos fármacos , Caules de Planta/fisiologia
2.
BMC Cancer ; 24(1): 764, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918786

RESUMO

OBJECTIVE: Clinically significant portal hypertension (CSPH) seriously affects the feasibility and safety of surgical treatment for hepatocellular carcinoma (HCC) patients. The aim of this study was to establish a new surgical scheme defining risk classification of post-hepatectomy liver failure (PHLF) to facilitate the surgical decision-making and identify suitable candidates for individual hepatectomy among HCC patients with CSPH. BACKGROUNDS: Hepatectomy is the preferred treatment for HCC. Surgeons must maintain a balance between the expected oncological outcomes of HCC removal and short-term risks of severe PHLF and morbidity. CSPH aggravates liver decompensation and increases the risk of severe PHLF thus complicating hepatectomy for HCC. METHODS: Multivariate logistic regression and stochastic forest algorithm were performed, then the independent risk factors of severe PHLF were included in a nomogram to determine the risk of severe PHLF. Further, a conditional inference tree (CTREE) through recursive partitioning analysis validated supplement the misdiagnostic threshold of the nomogram. RESULTS: This study included 924 patients, of whom 137 patients (14.8%) suffered from mild-CSPH and 66 patients suffered from (7.1%) with severe-CSPH confirmed preoperatively. Our data showed that preoperative prolonged prothrombin time, total bilirubin, indocyanine green retention rate at 15 min, CSPH grade, and standard future liver remnant volume were independent predictors of severe PHLF. By incorporating these factors, the nomogram achieved good prediction performance in assessing severe PHLF risk, and its concordance statistic was 0.891, 0.850 and 0.872 in the training cohort, internal validation cohort and external validation cohort, respectively, and good calibration curves were obtained. Moreover, the calculations of total points of diagnostic errors with 95% CI were concentrated in 110.5 (range 76.9-178.5). It showed a low risk of severe PHLF (2.3%), indicating hepatectomy is feasible when the points fall below 76.9, while the risk of severe PHLF is extremely high (93.8%) and hepatectomy should be rigorously restricted at scores over 178.5. Patients with points within the misdiagnosis threshold were further examined using CTREE according to a hierarchic order of factors represented by the presence of CSPH grade, ICG-R15, and sFLR. CONCLUSION: This new surgical scheme established in our study is practical to stratify risk classification in assessing severe PHLF, thereby facilitating surgical decision-making and identifying suitable candidates for individual hepatectomy.


Assuntos
Carcinoma Hepatocelular , Hepatectomia , Hipertensão Portal , Neoplasias Hepáticas , Nomogramas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Hepatectomia/métodos , Hepatectomia/efeitos adversos , Masculino , Feminino , Pessoa de Meia-Idade , Hipertensão Portal/cirurgia , Hipertensão Portal/etiologia , Idoso , Fatores de Risco , Complicações Pós-Operatórias/etiologia , Falência Hepática/etiologia , Falência Hepática/cirurgia , Estudos Retrospectivos , Adulto
3.
J Nanobiotechnology ; 22(1): 353, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38902759

RESUMO

Chemotherapy and immunotherapy have shown no significant outcome for unresectable pancreatic ductal adenocarcinoma (PDAC). Multi-drug combination therapy has become a consensus in clinical trials to explore how to arouse anti-tumor immunity and meanwhile overcome the poorly tumoricidal effect and the stroma barrier that greatly hinders drug penetration. To address this challenge, a comprehensive strategy is proposed to fully utilize both the ferroptotic vulnerability of PDAC to potently irritate anti-tumor immunity and the desmoplasia-associated focal adhesion kinase (FAK) to wholly improve the immunosuppressive microenvironment via sustained release of drugs in an injectable hydrogel for increasing drug penetration in tumor location and averting systematic toxicity. The injectable hydrogel ED-M@CS/MC is hybridized with micelles loaded with erastin that exclusively induces ferroptosis and a FAK inhibitor defactinib for inhibiting stroma formation, and achieves sustained release of the drugs for up to 12 days. With only a single intratumoral injection, the combination treatment with erastin and defactinib produces further anti-tumor performance both in xenograft and KrasG12D-engineered primary PDAC mice and synergistically promotes the infiltration of CD8+ cytotoxic T cells and the reduction of type II macrophages. The findings may provide a novel promising strategy for the clinical treatment of PDAC.


Assuntos
Carcinoma Ductal Pancreático , Hidrogéis , Neoplasias Pancreáticas , Animais , Hidrogéis/química , Carcinoma Ductal Pancreático/tratamento farmacológico , Camundongos , Neoplasias Pancreáticas/tratamento farmacológico , Humanos , Linhagem Celular Tumoral , Microambiente Tumoral/efeitos dos fármacos , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Sinergismo Farmacológico , Micelas , Imunoterapia/métodos
4.
Langenbecks Arch Surg ; 409(1): 97, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38488934

RESUMO

BACKGROUND: This study was recruited to compare the efficacy and safety of radiotherapy (RT) and transarterial chemoembolization (TACE) as postoperative adjuvant therapy after narrow-margin hepatectomy in hepatocellular carcinoma (HCC) patients. METHODS: This single-center prospective randomized study was conducted in the Cancer Hospital, Guang Xi Medical University, Nanning. A total of 72 patients who received treatment in this hospital between August 2017 and July 2019 were included and randomly allocated to TACE group (n = 48) and RT group (n = 24). Next, overall survival (OS) and progression-free survival (PFS) rates, recurrence patterns, financial burden, and safety were evaluated. RESULTS: The difference between the RT and TACE groups was not significant in one-, three-, and five-year OS (87.5%, 79.0%, and 62.5% vs. 93.8%, 75.9%, and 63.4%, respectively, P = 0.071) and PFS rates (79.0%, 54.2%, and 22.6% vs. 75.0%, 47.9%, and 32.6%, respectively, P = 0.071). Compared to the TACE group, the RT group had significantly lower intrahepatic recurrence rate (20.8% vs. 52.1%, P = 0.011), higher extrahepatic recurrence rate (37.5% vs. 14.6%, P = 0.034), and no marginal and diffuse recurrences (0% vs. 16.7%, P < 0.05). The mean overall treatment cost was higher (¥62,550.59 ± 4397.27 vs. ¥40,732.56 ± 9210.54, P < 0.01), the hospital stay (15.1 ± 3.7 vs. 11.8 ± 4.1 days, P < 0.01) was longer, and the overall treatment stay (13.3 ± 5.3 vs. 41.29 ± 12.4 days, P < 0.01) was shorter in the TACE group than in the RT group. Besides, both groups did not exhibit significant differences in the frequency and severity of adverse events. CONCLUSION: Both adjuvant TACE and RT can better the OS and PFS of patients with HCC. However, RT has a significantly better performance than TACE in terms of improving intrahepatic recurrence rate, treatment cost and hospital stay.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Hepatectomia , Estudos Prospectivos , Quimioembolização Terapêutica/efeitos adversos , Resultado do Tratamento , Estudos Retrospectivos
5.
Br J Cancer ; 127(2): 237-248, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35637410

RESUMO

BACKGROUND: Histone deacetylases (HDACs) have been shown to be involved in tumorigenesis, but their precise role and molecular mechanisms in gastric cancer (GC) have not yet been fully elucidated. METHODS: Bioinformatics screening analysis, qRT-PCR, and immunohistochemistry (IHC) were used to identify the expression of HDAC4 in GC. In vitro and in vivo functional assays illustrated the biological function of HDAC4. RNA-seq, GSEA pathway analysis, and western blot revealed that HDAC4 activated p38 MAPK signalling. Immunofluorescence, western blot, and IHC verified the effect of HDAC4 on autophagy. ChIP and dual-luciferase reporter assays demonstrated that the transcriptional regulation mechanism of HDAC4 and ATG4B. RESULTS: HDAC4 is upregulated in GC and correlates with poor prognosis. In vitro and in vivo assays showed that HDAC4 contributes to the malignant phenotype of GC cells. HDAC4 inhibited the MEF2A-driven transcription of ATG4B and prevented MEKK3 from p62-dependent autophagic degradation, thus activating p38 MAPK signalling. Reciprocally, the downstream transcription factor USF1 enhanced HDAC4 expression by regulating HDAC4 promoter activity, forming a positive feedback loop and continuously stimulating HDAC4 expression and p38 MAPK signalling activation. CONCLUSION: HDAC4 plays an oncogenic role in GC, and HDAC4-based targeted therapy would represent a novel strategy for GC treatment.


Assuntos
MAP Quinase Quinase Quinase 3/metabolismo , MicroRNAs , Neoplasias Gástricas , Autofagia/genética , Carcinogênese , Linhagem Celular Tumoral , Proliferação de Células , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , MicroRNAs/farmacologia , Proteínas Repressoras/genética , Neoplasias Gástricas/patologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética
6.
Glob Chang Biol ; 28(15): 4655-4667, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35567539

RESUMO

Seasonal differences in plant and microbial nitrogen (N) acquisition are believed to be a major mechanism that maximizes ecosystem N retention. There is also a concern that climate change may interrupt the delicate balance in N allocation between plants and microbes. Yet, convincing experimental evidence is still lacking. Using a 15 N tracer, we assessed how deepened snow affects the temporal coupling between plant and microbial N utilization in a temperate Mongolian grassland. We found that microbial 15 N recovery peaked in winter, accounting for 22% of the total ecosystem 15 N recovery, and then rapidly declined during the spring thaw. By stimulating N loss via N2 O emission and leaching, deepened snow reduced the total ecosystem 15 N recovery by 42% during the spring thaw. As the growing season progresses, the 15 N released from microbial biomass was taken up by plants, and the competitive advantage for N shifted from microbes to plants. Plant 15 N recovery reached its peak in August, accounting for 17% of the total ecosystem 15 N recovery. The Granger causality test showed that the temporal dynamics of plant 15 N recovery can be predicted by microbial 15 N recovery under ambient snow but not under deepened snow. In addition, plant 15 N recovery in August was positively correlated with and best explained by microbial 15 N recovery in March. The lower microbial 15 N recovery under deepened snow in March reduced plant 15 N recovery by 73% in August. Together, our results provide direct evidence of seasonal differences in plant and microbial N utilization that are conducive to ecosystem N retention; however, deepened snow disrupted the temporal coupling between plant-microbial N use and turnover. These findings suggest that changes in snowfall patterns may significantly alter ecosystem N cycling and N-based greenhouse gas emissions under future climate change. We highlight the importance of better representing winter processes and their response to winter climate change in biogeochemical models when assessing N cycling under global change.


Assuntos
Ecossistema , Neve , Nitrogênio/análise , Plantas , Estações do Ano , Solo
7.
Nanotechnology ; 34(3)2022 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-36219885

RESUMO

The serious side effects of cisplatin hindered its clinical application and the nanotechnology might be the potential strategy to address the limitation. However, rapid clearance in the blood circulation and ineffective controlled drug release from nanocarriers hamper the therapeutic efficacy of the nano-delivery system. We constructed a tumor microenvironment and redox dual stimuli-responsive nano-delivery system PEG-c-(BPEI-SS-Pt) by cross-linking the disulfide-containing polymeric conjugate BPEI-SS-Pt with the dialdehyde group-modified PEG2000via Schiff base. After optimized the cross-linking time, 72 h was selected to get the nano-delivery system.1H NMR and drug release assays showed that under the acidic tumor microenvironment (pH 6.5-6.8), the Schiff base can be broken and detached the PEG cross-linked outer shells, displaying the capability to release the drugs with a sequential pH- and redox-responsive manner. Moreover, PEG-c-(BPEI-SS-Pt) showed more effective anti-tumor therapeutic efficacyin vivowith no significant side effects when compared with the drug of cisplatin used in the clinic. This strategy highlights a promising platform with the dual stimuli-responsive profile to achieve better therapeutic efficacy and minor side effects for platinum-based chemotherapy.


Assuntos
Nanopartículas , Neoplasias , Humanos , Cisplatino/farmacologia , Cisplatino/uso terapêutico , Microambiente Tumoral , Bases de Schiff , Nanopartículas/química , Polímeros/química , Sistemas de Liberação de Medicamentos , Oxirredução , Neoplasias/tratamento farmacológico , Concentração de Íons de Hidrogênio , Linhagem Celular Tumoral
8.
Future Oncol ; 18(21): 2683-2694, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35699041

RESUMO

Background & aims: Finding a way to comprehensively integrate the presence and grade of clinically significant portal hypertension, amount of preserved liver function and extent of hepatectomy into the guidelines for choosing appropriate candidates to hepatectomy remained challenging. This study sheds light on these issues to facilitate precise surgical decisions for clinicians. Methods: Independent risk factors associated with grade B/C post-hepatectomy liver failure were identified by stochastic forest algorithm and logistic regression in hepatitis B virus-related hepatocellular carcinoma patients. Results: The artificial neural network model was generated by integrating preoperative pre-ALB, prothrombin time, total bilirubin, AST, indocyanine green retention rate at 15 min, standard future liver remnant volume and clinically significant portal hypertension grade. In addition, stratification of patients into three risk groups emphasized significant distinctions in the risk of grade B/C post-hepatectomy liver failure. Conclusion: The authors' artificial neural network model could provide a reasonable therapeutic option for clinicians to select optimal candidates with clinically significant portal hypertension for hepatectomy and supplement the hepatocellular carcinoma surgical treatment algorithm.


Hepatectomy involves removing the tumor from the liver and is considered the most effective treatment for hepatocellular carcinoma (HCC). Clinically significant portal hypertension is characterized by the presence of gastric and/or esophageal varices and a platelet count <100 × 109/l with the presence of splenomegaly, which would aggravate the risk of post-hepatectomy liver failure, and is therefore regarded as a contraindication to hepatectomy. Over the past few decades, with improvement in surgical techniques and perioperative care, the morbidity of postoperative complications and mortality have decreased greatly. Current HCC guidelines recommend the expansion of hepatectomy to HCC patients with clinically significant portal hypertension. However, determining how to select optimal candidates for hepatectomy remains challenging. The authors' artificial neural network is a mathematical tool developed by simulating the properties of neurons with large-scale information distribution and parallel structure. Here the authors retrospectively enrolled 871 hepatitis B virus-related HCC patients and developed an artificial neural network model to predict the risk of post-hepatectomy liver failure, which could provide a reasonable therapeutic option and facilitate precise surgical decisions for clinicians.


Assuntos
Carcinoma Hepatocelular , Hipertensão Portal , Falência Hepática , Neoplasias Hepáticas , Carcinoma Hepatocelular/patologia , Hepatectomia/efeitos adversos , Humanos , Hipertensão Portal/complicações , Hipertensão Portal/cirurgia , Falência Hepática/complicações , Falência Hepática/cirurgia , Neoplasias Hepáticas/patologia , Redes Neurais de Computação , Complicações Pós-Operatórias/etiologia , Estudos Retrospectivos
9.
Ann Surg ; 274(6): e1209-e1217, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32097166

RESUMO

OBJECTIVE: To develop a nomogram to estimate the risk of SPLD (International Study Group of Liver Surgery definition grade B or C) and long-term survival in patients with HCC before hepatectomy. BACKGROUND: SPLD is the leading cause of post-hepatectomy mortality. The decision to refer an HCC patient for hepatectomy is mainly based on the survival benefit and SPLD risk. Prediction of SPLD risk before hepatectomy is of great significance. METHODS: A total of 2071 consecutive patients undergoing hepatectomy for HCC were recruited and randomly divided into the development cohort (n = 1036) and internal validation cohort (n = 1035). Five hundred ninety patients from another center were enrolled as the external validation cohort. A nomogram was developed based on independent preoperative predictors of SPLD determined in multivariable logistic regression analysis. RESULTS: The SPLD incidences in the development, internal, and external validation cohorts were 10.1%, 9.5%, and 8.6%, respectively. Multivariable analysis identified total bilirubin, albumin, gamma-glutamyl transpeptidase, prothrombin time, clinically significant portal hypertension, and major resection as independent predictors for SPLD. Incorporating these variables, the nomogram showed good concordance statistics of 0.883, 0.851, and 0.856, respectively in predicting SPLD in the 3 cohorts. Its predictive performance in SPLD, 90-day mortality, and overall survival (OS) outperformed Child-Pugh, model for end-stage liver disease, albumin-bilirubin, and European Association for the Study of the Liver recommended algorithm. With a nomogram score of 137, patients were stratified into low and high risk of SPLD. High-risk patients also had decreased OS. CONCLUSIONS: The nomogram showed good performance in predicting both SPLD and OS. It could help surgeons select suitable HCC patients for hepatectomy.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia , Falência Hepática/etiologia , Neoplasias Hepáticas/cirurgia , Complicações Pós-Operatórias/etiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Nomogramas , Valor Preditivo dos Testes , Fatores de Risco , Índice de Gravidade de Doença
10.
New Phytol ; 229(5): 2601-2610, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33112419

RESUMO

Forest canopies can retain nitrogen (N) from atmospheric deposition. However, most empirical and modeling studies do not consider the processing of the N deposited in the canopy. To assess whether N deposition through canopy will alter the plant's N uptake and retention, we conducted a 3-yr mesocosm experiment by applying (15 NH4 )2 SO4 solution to aspen sapling canopies or directly to the soil. We found that 15 N-NH4+ applied to the canopy was directly taken up by leaves. Compared with the soil N application, the canopy N application resulted in higher photosynthesis but lower N retention of the plant-soil system in the first growing season. Plant biomass, N concentration, and leaf N resorption were not significantly different between the canopy and soil N applications. The partitioning of retained 15 N among plant components and soil layers was similar between the two treatments 3 yr after the N application. Our findings indicated that the canopy N processing could alter leaf N supply and photosynthesis in the short term but not N retention in the long term. Under natural conditions, the chronic N deposition could continuously refill the canopy N pool, causing a sustained increase in canopy carbon uptake. Canopy N processing needs to be considered for accurately predicting the impact of N deposition.


Assuntos
Fotossíntese , Plântula , Florestas , Nitrogênio , Folhas de Planta
11.
BMC Cancer ; 21(1): 283, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33726693

RESUMO

BACKGROUND: The accurate prediction of post-hepatectomy early recurrence (PHER) of hepatocellular carcinoma (HCC) is vital in determining postoperative adjuvant treatment and monitoring. This study aimed to develop and validate an artificial neural network (ANN) model to predict PHER in HCC patients without macroscopic vascular invasion. METHODS: Nine hundred and three patients who underwent curative liver resection for HCC participated in this study. They were randomly divided into derivation (n = 679) and validation (n = 224) cohorts. The ANN model was developed in the derivation cohort and subsequently verified in the validation cohort. RESULTS: PHER morbidity in the derivation and validation cohorts was 34.8 and 39.2%, respectively. A multivariable analysis revealed that hepatitis B virus deoxyribonucleic acid load, γ-glutamyl transpeptidase level, α-fetoprotein level, tumor size, tumor differentiation, microvascular invasion, satellite nodules, and blood loss were significantly associated with PHER. These factors were incorporated into an ANN model, which displayed greater discriminatory abilities than a Cox's proportional hazards model, preexisting recurrence models, and commonly used staging systems for predicting PHER. The recurrence-free survival curves were significantly different between patients that had been stratified into two risk groups. CONCLUSION: When compared to other models and staging systems, the ANN model has a significant advantage in predicting PHER for HCC patients without macroscopic vascular invasion.


Assuntos
Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Recidiva Local de Neoplasia/epidemiologia , Redes Neurais de Computação , Nomogramas , Carcinoma Hepatocelular/diagnóstico , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Intervalo Livre de Doença , Feminino , Seguimentos , Hepatectomia , Humanos , Fígado/diagnóstico por imagem , Fígado/patologia , Fígado/cirurgia , Neoplasias Hepáticas/diagnóstico , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/prevenção & controle , Estadiamento de Neoplasias , Período Pós-Operatório , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Fatores de Risco
12.
Curr Microbiol ; 78(4): 1648-1655, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33651189

RESUMO

Phycosphere hosts the boundary of unique holobionts harboring dynamic algae-bacteria interactions. During our investigating the microbial consortia composition of phycosphere microbiota (PM) derived from diverse harmful algal blooms (HAB) dinoflagellates, a novel rod-shaped, motile and faint yellow-pigmented bacterium, designated as strain LZ-6 T, was isolated from HAB Alexandrium catenella LZT09 which produces high levels paralytic shellfish poisoning toxins. Phylogenetic analysis based on 16S rRNA gene and two housekeeping genes, rpoA and pheS sequences showed that the novel isolate shared the highest gene similarity with Marinobacter shengliensis CGMCC 1.12758 T (99.6%) with the similarity values of 99.6%, 99.9% and 98.5%, respectively. Further phylogenomic calculations of average nucleotide identity (ANI), average amino acid identity (AAI) and digital DNA-DNA hybridization (dDDH) values between strains LZ-6 T and the type strain of M. shengliensis were 95.9%, 96.4% and 68.5%, respectively. However, combined phenotypic and chemotaxonomic characterizations revealed that the new isolate was obviously different from the type strain of M. shengliensis. The obtained taxonomic evidences supported that strain LZ-6 T represents a novel subspecies of M. shengliensis, for which the name is proposed, Marinobacter shengliensis subsp. alexandrii subsp. nov. with the type strain LZ-6 T (= CCTCC AB 2018388TT = KCTC 72197 T). This proposal automatically creates Marinobacter shengliensis subsp. shengliensis for which the type strain is SL013A34A2T (= LMG 27740 T = CGMCC 1.12758 T).


Assuntos
Dinoflagellida , Microbiota , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Dinoflagellida/genética , Ácidos Graxos/análise , Marinobacter , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Pestic Biochem Physiol ; 177: 104892, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34301354

RESUMO

Ralstonia solanacearum (R. solanacearum) is one of the most devastating bacterial pathogens and leads to serious economic losses in crops worldwide. In this study, the antibacterial activities of novel plant-derived coumarins against R. solanacearum and their underlying mechanisms were initially investigated. The bioactivity assay results showed that certain coumarins had significant in vitro inhibitory effects against R. solanacearum. Notably, 6-methylcoumarin showed the best in vitro antibacterial activity with 76.79%. Interestingly, 6-methylcoumarin was found to cause cell elongation, disrupt cell division, and suppress the expression of the bacterial division protein coding genes ftsZ. Compared with the control treatment, the ∆ftsZ mutant inhibited bacterial growth and caused the bacteria to be more sensitive to 6-methylcoumarin. The application of 6-methylcoumarin effectively suppressed the development of tobacco bacterial wilt in pot and field experiments, and significantly reduced the bacterial population in tobacco stems. The control efficiency of 6-methylcoumarin treatment was 35.76%, 40.51%, 38.99% at 10, 11, and 12 weeks after tobacco transplantation in field condition. All of these results demonstrate that 6-methylcoumarin has potential as an eco-friendly and target specificity agent for controlling tobacco bacterial wilt.


Assuntos
Ralstonia solanacearum , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Doenças das Plantas , Nicotiana
14.
J Cell Mol Med ; 24(13): 7637-7651, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32436333

RESUMO

The mechanism by which miR-605-3p regulates hepatocellular carcinoma (HCC) metastasis has not been clarified. In this study, we found that miR-605-3p was down-regulated in HCC and that low miR-605-3p expression was associated with tumour thrombus and tumour satellites. HCC patients with low miR-605-3p expression showed shorter overall survival and disease-free survival after surgery. Overexpression of miR-605-3p inhibited epithelial-mesenchymal transition and metastasis of HCC through NF-κB signalling by directly inhibiting expression of TRAF6, while silencing of miR-605-3p had the opposite effect. We also found that SNHG16 directly bound to miR-605-3p as a competing endogenous RNA. Mechanistically, high expression of SNHG16 promoted binding to miR-605-3p and inhibited its activity, which led to up-regulation of TRAF6 and sustained activation of the NF-κB pathway, which in turn promoted epithelial-mesenchymal transition and metastasis of HCC. TRAF6 increased SNHG16 promoter activity by activating NF-κB, thereby promoting the transcriptional expression of SNHG16 and forming a positive feedback loop that aggravated HCC malignancy. Our findings reveal a mechanism for the sustained activation of the SNHG16/miR-605-3p/TRAF6/NF-κB feedback loop in HCC and provide a potential target for a new HCC treatment strategy.


Assuntos
Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Retroalimentação Fisiológica , Neoplasias Hepáticas/genética , MicroRNAs/metabolismo , NF-kappa B/metabolismo , RNA Longo não Codificante/metabolismo , Fator 6 Associado a Receptor de TNF/metabolismo , Sequência de Bases , Linhagem Celular Tumoral , Sobrevivência Celular/genética , Intervalo Livre de Doença , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Masculino , MicroRNAs/genética , Pessoa de Meia-Idade , Análise Multivariada , Metástase Neoplásica , Prognóstico , RNA Longo não Codificante/genética
15.
Glob Chang Biol ; 26(5): 3015-3027, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32107822

RESUMO

Global warming has greatly altered winter snowfall patterns, and there is a trend towards increasing winter snow in semi-arid regions in China. Winter snowfall is an important source of water during early spring in these water-limited ecosystems, and it can also affect nutrient supply. However, we know little about how changes in winter snowfall will affect ecosystem productivity and plant community structure during the growing season. Here, we conducted a 5-year winter snow manipulation experiment in a temperate grassland in Inner Mongolia. We measured ecosystem carbon flux from 2014 to 2018 and plant biomass and species composition from 2015 to 2018. We found that soil moisture increased under deepened winter snow in early growing season, particularly in deeper soil layers. Deepened snow increased the net ecosystem exchange of CO2 (NEE) and reduced intra- and inter-annual variation in NEE. Deepened snow did not affect aboveground plant biomass (AGB) but significantly increased root biomass. This suggested that the enhanced NEE was allocated to the belowground, which improved water acquisition and thus contributed to greater stability in NEE in deep-snow plots. Interestingly, the AGB of grasses in the control plots declined over time, resulting in a shift towards a forb-dominated system. Similar declines in grass AGB were also observed at three other locations in the region over the same time frame and are attributed to 4 years of below-average precipitation during the growing season. By contrast, grass AGB was stabilized under deepened winter snow and plant community composition remained unchanged. Hence, our study demonstrates that increased winter snowfall may stabilize arid grassland systems by reducing resource competition, promoting coexistence between plant functional groups, which ultimately mitigates the impacts of chronic drought during the growing season.


Assuntos
Ecossistema , Neve , China , Pradaria , Estações do Ano
16.
BMC Cancer ; 20(1): 1036, 2020 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-33115425

RESUMO

BACKGROUND: To develop a nomogram for predicting the International Study Group of Liver Surgery (ISGLS) grade B/C posthepatectomy liver failure (PHLF) in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) patients. METHODS: Patients initially treated with hepatectomy were included. Univariate regression analysis and stochastic forest algorithm were applied to extract the core indicators and reduce redundancy bias. The nomogram was then constructed by using multivariate logistic regression, and validated in internal and external cohorts, and a prospective clinical application. RESULTS: There were 900, 300 and 387 participants in training, internal and external validation cohorts, with the morbidity of grade B/C PHLF were 13.5, 11.0 and 20.2%, respectively. The nomogram was generated by integrating preoperative total bilirubin, platelet count, prealbumin, aspartate aminotransferase, prothrombin time and standard future liver remnant volume, then achieved good prediction performance in training (AUC = 0.868, 95%CI = 0.836-0.900), internal validation (AUC = 0.868, 95%CI = 0.811-0.926) and external validation cohorts (AUC = 0.820, 95%CI = 0.756-0.861), with well-fitted calibration curves. Negative predictive values were significantly higher than positive predictive values in training cohort (97.6% vs. 33.0%), internal validation cohort (97.4% vs. 25.9%) and external validation cohort (94.3% vs. 41.1%), respectively. Patients who had a nomogram score < 169 or ≧169 were considered to have low or high risk of grade B/C PHLF. Prospective application of the nomogram accurately predicted grade B/C PHLF in clinical practise. CONCLUSIONS: The nomogram has a good performance in predicting ISGLS grade B/C PHLF in HBV-related HCC patients and determining appropriate candidates for hepatectomy.


Assuntos
Carcinoma Hepatocelular/cirurgia , Hepatectomia/efeitos adversos , Hepatite B/complicações , Falência Hepática/diagnóstico , Neoplasias Hepáticas/cirurgia , Nomogramas , Complicações Pós-Operatórias/diagnóstico , Adolescente , Adulto , Idoso , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Feminino , Seguimentos , Hepatite B/patologia , Hepatite B/virologia , Vírus da Hepatite B , Humanos , Falência Hepática/etiologia , Falência Hepática/patologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/patologia , Prognóstico , Estudos Prospectivos , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
17.
Fish Shellfish Immunol ; 104: 222-227, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32531332

RESUMO

Cryptocaryon irritans is an extremely harmful ciliated obligate parasite that is responsible for large economic losses in aquaculture. C. irritans infection can cause an insect-resistant immune response in fish, and many immune cells can be observed in the local infection site. However, it is unclear whether macrophages are involved in the host defense against C. irritans infection. The Mpeg1 protein can form pores and destroy the cell membrane of invading pathogens, and is also used as a macrophage-specific marker in mammals. Therefore, a polyclonal antibody against grouper recombinant Mpeg1a was produced to mark macrophages in this study, which could recognize both isoforms of Mpeg1 (Mpeg1a/b). Immunofluorescence revealed that EcMpeg1 positive cells were mostly distributed in the head kidney and spleen in healthy grouper. Immunofluorescence and immunohistochemistry showed that the number of EcMpeg1 positive cells increased in the gills after infection with C. irritans, implying that EcMpeg1 positive cells may be involved in the process of grouper resistance against C. irritans infection.


Assuntos
Infecções por Cilióforos/imunologia , Cilióforos , Doenças dos Peixes/imunologia , Proteínas de Peixes/imunologia , Proteínas de Membrana/imunologia , Perciformes/imunologia , Animais , Infecções por Cilióforos/veterinária , Resistência à Doença/imunologia , Proteínas de Peixes/genética , Brânquias/imunologia , Macrófagos/imunologia , Proteínas de Membrana/genética , Perciformes/microbiologia
18.
Exp Cell Res ; 385(2): 111691, 2019 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-31678170

RESUMO

Rafoxanide is commonly used as anti-helminthic medicine in veterinary medicine, a main compound of salicylanilide. Previous studies have reported that rafoxanide, as an inhibitor of BRAF V600E mutant protein, inhibits the growth of colorectal cancer, multiple myeloma, and skin cancer. However, its therapeutic effect on gastric cancer (GC) and the potential mechanism has not been investigated. Here, we have found that rafoxanide inhibited the proliferation of GC cells in vitro, arrested the cell cycle in the G0/G1 phase, and promoted apoptosis and autophagy in GC cells. Treatment with specific autophagy inhibitor 3-methyladenine drastically inhibited the apoptotic cell death effect by suppressing the switch from autophagy to apoptosis. Mechanistically, we found that rafoxanide inhibited the growth of GC cells in vitro by inhibiting the activity of the PI3K/Akt/mTOR signaling pathway. This process induced autophagy, which essentially resulted in the apoptosis of GC cells. Results from subcutaneous implanted tumor models in nude mice also indicated that rafoxanide inhibited the growth of GC cells in vivo. Taken together, our findings revealed that rafoxanide inhibited the growth of GC cells both in vitro and vivo, indicating a potential drug candidate for the treatment of GC.


Assuntos
Antineoplásicos/uso terapêutico , Antiplatelmínticos/uso terapêutico , Apoptose , Autofagia , Rafoxanida/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Animais , Antineoplásicos/farmacologia , Antiplatelmínticos/farmacologia , Linhagem Celular Tumoral , Proliferação de Células , Humanos , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Rafoxanida/farmacologia , Serina-Treonina Quinases TOR/metabolismo
19.
J Fish Dis ; 43(12): 1541-1552, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32924190

RESUMO

Cryptocaryon irritans, a pathogen model for fish mucosal immunity, causes skin mucosal and systematic humoral immune response. Where and how MHC II antigen presentation occurs in fish infected with C. irritans remain unknown. In this study, the full-length cDNA of the grouper cysteine protease CTSS was cloned. The expression distributions of six genes (CTSB, CTSL, CTSS, GILT, MHC IIA and MHC IIB) involved in MHC II antigen presentation pathway were tested. These genes were highly expressed in systematic immune tissues and skin and gill mucosal-associated immune tissues. All six genes were upregulated in skin at most time points. Five genes expected CTSS was upregulated in spleen at most time points. CTSB, CTSL and MHC IIA were upregulated in the gill and head kidney at some time points. These results indicate that the presentation of MHC II antigen intensively occurred in local infected skin and gill. Spleen, not head kidney, had the most extensive systematic antigen presentation. In skin, six genes most likely peaked at day 2, earlier than in spleen (5-7 days), marking an earlier skin antibody peak than any recorded in serum previously. This significant and earlier mucosal antigen presentation indicates that specific immune response occurs in local mucosal tissues.


Assuntos
Bass , Infecções por Cilióforos/imunologia , Doenças dos Peixes/parasitologia , Complexo Principal de Histocompatibilidade/genética , Animais , Antígenos de Protozoários , Doenças dos Peixes/genética , Doenças dos Peixes/imunologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/imunologia , Hymenostomatida/fisiologia , Imunidade Humoral , Imunidade nas Mucosas/genética
20.
Fish Shellfish Immunol ; 86: 1081-1087, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30593900

RESUMO

Antimicrobial peptides (AMPs) are small proteins showing broad-spectrum antimicrobial activity that have been known to be powerful agents against a variety of pathogens (bacteria, fungi and viruses). In this study, the effects of AMPs from Bacillus subtilis on Epinephelus coioides were examined. E. coioides were fed with diets containing AMPs (0, 100, 200, 400 or 800 mg/kg) for four weeks. Results showed that the levels of total protein (TP), albumin (ALB), alanine aminotransferase (ALT), aspartate aminotransferase (AST), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and blood glucose (GLU) and lipopolysaccharide (LPS) in the serum of E. coioides changed than those of the control group; compared to the control group, the levels of total antioxidant capacity (T-AOC), superoxide dismutase (SOD), catalase (CAT), malondialdehyde (MDA) and lysozyme (LZM) levels in E. coioides fed with different dosages AMP diets were also different; in addition, the mRNA expression of tumor necrosis factor alpha (TNF-α), interleukin-1-beta (IL-1ß), and heat shock protein 90 (Hsp90) in the tissues of E. coioides were measured, the three genes in the tissues examined were significantly upregulated. The results demonstrated that diets containing AMPs can enhance the antioxidant capacity and innate immune ability of E. coioides, indicating that AMPs might be a potential alternative to antibiotics in E. coioides.


Assuntos
Peptídeos Catiônicos Antimicrobianos/farmacologia , Antioxidantes/metabolismo , Bass/imunologia , Imunidade Inata , Ração Animal/análise , Animais , Peptídeos Catiônicos Antimicrobianos/administração & dosagem , Bacillus subtilis/química , Bass/metabolismo , Análise Química do Sangue/veterinária , Dieta/veterinária
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