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1.
Appl Environ Microbiol ; 90(4): e0227423, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38470181

RESUMO

Vibrio species are prevalent in ocean ecosystems, particularly Vibrio coralliilyticus, and pose a threat to corals and other marine organisms under global warming conditions. While microbiota manipulation is considered for coral disease management, understanding the role of commensal bacteria in stress resilience remains limited. Here, a single bacterial species (Ruegeria profundi) rather than a consortium of native was used to combat pathogenic V. coralliilyticus and protect corals from bleaching. R. profundi showed therapeutic activity in vivo, preventing a significant reduction in bacterial diversity in bleached corals. Notably, the structure of the bacterial community differed significantly among all the groups. In addition, compared with the bleached corals caused by V. coralliilyticus, the network analysis revealed that complex interactions and positive correlations in the bacterial community of the R. profundi protected non-bleached corals, indicating R. profundi's role in fostering synergistic associations. Many genera of bacteria significantly increased in abundance during V. coralliilyticus infection, including Vibrio, Alteromonas, Amphritea, and Nautella, contributing to the pathogenicity of the bacterial community. However, R. profundi effectively countered the proliferation of these genera, promoting potential probiotic Endozoicomonas and other taxa, while reducing the abundance of betaine lipids and the type VI section system of the bacterial community. These changes ultimately influenced the interactive relationships among symbionts and demonstrated that probiotic R. profundi intervention can modulate coral-associated bacterial community, alleviate pathogenic-induced dysbiosis, and preserve coral health. These findings elucidated the relationship between the behavior of the coral-associated bacterial community and the occurrence of pathological coral bleaching.IMPORTANCEChanges in the global climate and marine environment can influence coral host and pathogen repartition which refers to an increased likelihood of pathogen infection in hosts. The risk of Vibrio coralliilyticus-induced coral disease is significantly heightened, primarily due to its thermos-dependent expression of virulent and populations. This study investigates how coral-associated bacterial communities respond to bleaching induced by V. coralliilyticus. Our findings demonstrate that Ruegeria profundi exhibits clear evidence of defense against pathogenic bacterial infection, contributing to the maintenance of host health and symbiont homeostasis. This observation suggests that bacterial pathogens could cause dysbiosis in coral holobionts. Probiotic bacteria display an essential capability in restructuring and manipulating coral-associated bacterial communities. This restructuring effectively reduces bacterial community virulence and enhances the pathogenic resistance of holobionts. The study provides valuable insights into the correlation between the health status of corals and how coral-associated bacterial communities may respond to both pathogens and probiotics.


Assuntos
Antozoários , Rhodobacteraceae , Vibrio , Animais , Branqueamento de Corais , Ecossistema , Disbiose , Antozoários/microbiologia , Recifes de Corais
2.
BMC Cancer ; 24(1): 321, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454345

RESUMO

BACKGROUND: Definitive concurrent chemoradiotherapy (dCCRT) is the gold standard for the treatment of locally advanced esophageal squamous cell carcinoma (ESCC). However, the potential benefits of consolidation chemotherapy after dCCRT in patients with esophageal cancer remain debatable. Prospective randomized controlled trials comparing the outcomes of dCCRT with or without consolidation chemotherapy in patients with ESCC are lacking. In this study, we aim to generate evidence regarding consolidation chemotherapy efficacy in patients with locally advanced, inoperable ESCC. METHODS: This is a multicenter, prospective, open-label, phase-III randomized controlled trial comparing non-inferiority of dCCRT alone to consolidation chemotherapy following dCCRT. In total, 600 patients will be enrolled and randomly assigned in a 1:1 ratio to receive either consolidation chemotherapy after dCCRT (Arm A) or dCCRT alone (Arm B). Overall survival will be the primary endpoint, whereas progression-free survival, locoregional progression-free survival, distant metastasis-free survival, and treatment-related toxicity will be the secondary endpoints. DISCUSSION: This study aid in further understanding the effects of consolidation chemotherapy after dCCRT in patients with locally advanced, inoperable ESCC. TRIAL REGISTRATION: ChiCTR1800017646.


Assuntos
Neoplasias Esofágicas , Carcinoma de Células Escamosas do Esôfago , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Quimiorradioterapia , Quimioterapia de Consolidação , Neoplasias Esofágicas/tratamento farmacológico , Neoplasias Esofágicas/radioterapia , Carcinoma de Células Escamosas do Esôfago/terapia , Carcinoma de Células Escamosas do Esôfago/patologia , Estudos Prospectivos , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase III como Assunto , Estudos de Equivalência como Asunto
3.
Eur Radiol ; 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844619

RESUMO

OBJECTIVES: Despite some existing studies on the safety of high static magnetic fields (SMFs), the effects of ultra-high SMFs above 20.0 T for embryonic development in early pregnancy are absent. The objective of this study is to evaluate the influence of 16.8-22.0 T SMF on the development of zebrafish embryos, which will provide important information for the future application of ultra-high field magnetic resonance imaging (MRI). METHODS: Two-hour exposure to homogenous (0 T/m) 22.0 T SMF, or 16.8 T SMFs with 123.25 T/m spatial gradient of opposite magnetic force directions was examined in the embryonic development of 200 zebrafish. Their body length, heart rate, spontaneous tail-wagging movement, hatching and survival rate, photomotor response, and visual motor response (VMR) were analyzed. RESULTS: Our results show that these ultra-high SMFs did not significantly affect the general development of zebrafish embryos, such as the body length or spontaneous tail-wagging movement. However, the hatching rate was reduced by the gradient SMFs (p < 0.05), but not the homogenous 22.0 T SMF. Moreover, although the zebrafish larva activities were differentially affected by these ultra-high SMFs (p < 0.05), the expression of several visual and neurodevelopmental genes (p < 0.05) was generally downregulated in the eyeball. CONCLUSIONS: Our findings suggest that exposure to ultra-high SMFs, especially the gradient SMFs, may have adverse effects on embryonic development, which should cause some attention to the future application of ultra-high field MRIs. CLINICAL RELEVANCE STATEMENT: As technology advances, it is conceivable that very strong magnetic fields may be adapted for use in medical imaging. Possible dangers associated with these higher Tesla fields need to be considered and evaluated prior to human use. KEY POINTS: Ultra-High static magnetic field may affect early embryonic development. High strength gradient static magnetic field exposure impacted zebrafish embryonic development. The application of very strong magnetic fields for MR technologies needs to be carefully evaluated.

4.
Environ Res ; 252(Pt 2): 118813, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38574985

RESUMO

After the second industrial revolution, social productivity developed rapidly, and the use of fossil fuels such as coal, oil, and natural gas increased greatly in industrial production. The burning of these fossil fuels releases large amounts of greenhouse gases such as CO2, which has caused greenhouse effects and global warming. This has endangered the planet's ecological balance and brought many species, including animals and plants, to the brink of extinction. Thus, it is crucial to address this problem urgently. One potential solution is the use of syngas fermentation with microbial cell factories. This process can produce chemicals beneficial to humans, such as ethanol as a fuel while consuming large quantities of harmful gases, CO and CO2. However, syngas-fermenting microorganisms often face a metabolic energy deficit, resulting in slow cell growth, metabolic disorders, and low product yields. This problem limits the large-scale industrial application of engineered microorganisms. Therefore, it is imperative to address the energy barriers of these microorganisms. This paper provides an overview of the current research progress in addressing energy barriers in bacteria, including the efficient capture of external energy and the regulation of internal energy metabolic flow. Capturing external energy involves summarizing studies on overexpressing natural photosystems and constructing semiartificial photosynthesis systems using photocatalysts. The regulation of internal energy metabolic flows involves two parts: regulating enzymes and metabolic pathways. Finally, the article discusses current challenges and future perspectives, with a focus on achieving both sustainability and profitability in an economical and energy-efficient manner. These advancements can provide a necessary force for the large-scale industrial application of syngas fermentation microbial cell factories.


Assuntos
Fermentação , Bactérias/metabolismo , Metabolismo Energético , Biocombustíveis
5.
Mol Biol Rep ; 50(6): 5425-5438, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37101007

RESUMO

Since cells are the basic structural and functional units of organisms, the detection or quantitation of cells is one of the most common basic problems in life science research. The established cell detection techniques mainly include fluorescent dye labeling, colorimetric assay, and lateral flow assay, all of which employ antibodies as cell recognition elements. However, the widespread application of the established methods generally dependent on antibodies is limited, because the preparation of antibodies is complicated and time-consuming, and unrecoverable denaturation is prone to occur with antibodies. By contrast, aptamers that are generally selected through the systematic evolution of ligands by exponential enrichment can avoid the disadvantages of antibodies due to their controllable synthesis, thermostability, and long shelf life, etc. Accordingly, aptamers may serve as novel molecular recognition elements like antibodies in combination with various techniques for cell detection. This paper reviews the developed aptamer-based cell detection methods, mainly including aptamer-fluorescent labeling, aptamer-isothermal amplification assay, electrochemical aptamer sensor, aptamer-based lateral flow analysis, and aptamer-colorimetric assay. The principles, advantages, progress of application in cell detection and future development trend of these methods were specially discussed. Overall, different assays are suitable for different detection purposes, and the development of more accurate, economical, efficient, and rapid aptamer-based cell detection methods is always on the road in the future. This review is expected to provide a reference for achieving efficient and accurate detection of cells as well as improving the usefulness of aptamers in the field of analytical applications.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Aptâmeros de Nucleotídeos/química , Corantes Fluorescentes , Ligantes , Anticorpos/química , Tecnologia , Técnicas Biossensoriais/métodos
6.
Phys Chem Chem Phys ; 25(13): 9225-9237, 2023 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-36919457

RESUMO

With excellent physical and chemical properties, 2D TMDC materials have been widely used in engineering applications, but they inevitably suffer from the dual effects of strain and device size. As typical 2D TMDCs, HfSe2 and ZrS2 are reported to have excellent thermoelectric properties. Thermal transport properties have great significance for exerting the performance of materials, ensuring device lifetime and stable operation, but current research is not detailed enough. Here, first-principles combined with the phonon Boltzmann transport equation are used to study the phonon transport inside monolayer HfSe2 and ZrS2 under tensile strain and finite size, and explore the band structure properties. Our research shows that they have similar phonon dispersion curve structures, and the band gap of HfSe2 increases monotonically with the increase of tensile strain, while the bandgap of ZrS2 increases and then decreases with the increase of tensile strain. Thermal conductivity has obvious strain dependence: with the increase of tensile strain, the thermal conductivity of HfSe2 gradually decreases, while that of ZrS2 increases slightly, and then gradually decreases. Reducing the system size can limit the contribution of phonons with a long mean free path, significantly decreasing thermal conductivity through the controlling effect of tensile strain. The mode contribution of thermal conductivity is systematically investigated, and anharmonic properties including mode and frequency-level scattering rates, group velocity and Grüneisen parameters are used to explain the associated mechanism. Phonon scattering processes and channels in various cases are discussed in detail. Our research provides a detailed understanding of the phonon transport and electronic structural properties of low thermal conductivity monolayers of HfSe2 and ZrS2, and further completes the study of thermal transport of the two materials under strain and size tuning, which will provide a foundation for further popularization and application.

7.
Environ Res ; 220: 115099, 2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36563978

RESUMO

Harmful algal blooms (HABs) caused by Prorocentrum minimum have seriously posed economic losses and ecological disasters. To reduce these losses, aptamers are used as a new molecular probe to establish rapid methods. Herein, to improve the affinity and application of aptamers in the detection of harmful algae, the optimization was performed on the previously reported aptamers against P. minimum. First, a total of seven candidate aptamers, including three truncated aptamers (TA1, TA2 and TA3) and four mutant aptamers (MA1, MA2, MA3 and MA4), were obtained by truncation and G-quadruplex (GQ)-forming mutation. Next, the specificity and affinity test by flow cytometry revealed that except for TA1 and TA2, all of the candidate aptamers are specific with the equilibrium dissociation constant of (40.4 ± 5.5) nM for TA3, (63.3 ± 24.0) nM for MA1, (71.7 ± 14.6) nM for MA2, (365.9 ± 74.4) nM for MA3, and (21.1 ± 0.5) nM for MA4, respectively. The circular dichroism analysis of the mutant aptamers demonstrated that the GQ structures formed by MA1/MA2, MA3 and MA4 were antiparallel, mixed parallel and parallel, respectively. The affinity of aptamers with various GQ is in the order of parallel structure > antiparallel structure > mixed parallel structure. In addition, to further improve binding ability, the binding conditions of MA4 were optimized as follows: binding time, 60 min; binding temperature, 37 °C; pH of the binding buffer, 7.5; and Na+/Mg2+ concentration in the binding buffer, 100 mM/0.5 mM. The binding examination by fluorescence microscopy showed that MA4 had a stronger binding ability to P. minimum than the original aptamer. Taken together, this study not only obtained an aptamer with higher affinity than the original aptamer, which laid a good foundation for subsequent application, but also may provide a feasible reference method for aptamer optimization.


Assuntos
Aptâmeros de Nucleotídeos , Quadruplex G , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/genética , Sondas Moleculares
8.
Environ Res ; 238(Pt 2): 117221, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37775014

RESUMO

Quorum sensing (QS) and quorum quenching (QQ) are two antagonistic processes that may regulate the composition, function and structure of bacterial community. In coral holobiont, autoinducers signaling mediate the communication pathways between interspecies and intraspecies bacteria, which regulate the expression of the virulence factors that can damage host health. However, under environmental stressors, the interaction between the QS/QQ gene and virulence factors and their role in the bacterial communities and coral bleaching is still not fully clear. To address this question, here, metagenomics method was used to examine the profile of QS/QQ and virulence genes from a deeply sequenced microbial database, obtained from three bleached and non-bleached corals species. The prediction of bacterial genes of bleached samples involved in functional metabolic pathways were remarkably decreased, and the bacterial community structure on bleached samples was significantly different compared to non-bleached samples. The distribution and significant difference in QS/QQ and virulence genes were also carried out. We found that Proteobacteria was dominant bacteria among all samples, and AI-1 system is widespread within this group of bacteria. The identified specific genes consistently exhibited a trend of increased pathogenicity in bleached corals relative to non-bleached corals. The abundance of pathogenicity-associated QS genes, including bapA, pfoA and dgcB genes, were significantly increased in bleached corals and can encode the protein of biofilm formation and the membrane damaging toxins promoting pathogenic adhesion and infection. Similarly, the virulence genes, such as superoxide dismutase (Mn-SOD gene), metalloproteinase (yme1, yydH and zmpB), glycosidases (malE, malF, malG, and malK) and LodAB (lodB) genes significantly increased. Conversely, QQ genes that inhibit QS activity and virulence factors to defense the pathogens, including blpA, lsrK, amiE, aprE and gmuG showed a significant decrease in bleached groups. Furthermore, the significant correlations were found among virulence, QS/QQ genes, and coral associated bacterial community, and the virulence genes interact with key QS/QQ genes, directly or indirectly influence symbiotic bacterial communities homeostasis, thereby impacting coral health. It suggested that the functional and structural divergence in the symbiont bacteria may be partially attribute to the interplay, involving interactions among the host, bacterial communication signal systems, and bacterial virulence factors. In conclusion, these data helped to reveal the characteristic behavior of coral symbiotic bacteria, and facilitated a better understanding of bleaching mechanism from a chemical ecological perspective.


Assuntos
Antozoários , Percepção de Quorum , Animais , Percepção de Quorum/genética , Virulência , Bactérias/metabolismo , Fatores de Virulência
9.
Int Wound J ; 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37779328

RESUMO

The application of a tourniquet (TNQ) for haemostasis in total knee arthroplasty (TKA) is controversial and lacking systematic evaluation. This meta-analysis assessed relevant international data to quantitatively evaluate the implications of using TNQ in TKA, further guide clinical diagnosis and treatment, and improve postoperative outcomes. A comprehensive computerised search of PubMed, Embase, Cochrane Library, Chinese National Knowledge Infrastructure, VIP, and Wanfang databases was conducted to retrieve randomised controlled trials on the application of TNQ in TKA published from database inception to August 2023. The included data, ultimately comprising 1482 patients in 16 studies, were collated and subjected to meta-analysis using Stata 17.0 software. The results showed that the use of TNQ during TKA led to significantly higher rates of postoperative surgical site wound infection (3.96% vs. 1.79%, odds ratio: 2.15, 95% confidence intervals [CIs]: 1.11-4.16, p = 0.023) and wound pain scores on the first (standardised mean difference [SMD]: 0.65, 95% CI: 0.35-0.94, p < 0.001), second (SMD: 0.66, 95% CI: 0.01-1.31, p = 0.045), and third (SMD: 0.68, 95% CI: 0.31-1.05, pP < 0.001) day after the procedure. In conclusion, the application of TNQ in TKA increases the risk of postoperative surgical site wound infection and worsens short-term postoperative wound pain; therefore, TNQ should be used sparingly during TKA, or its use should be decided in conjunction with the relevant clinical indications and the surgeon's experience.

10.
Mol Biol Rep ; 49(8): 7979-7993, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35274201

RESUMO

BACKGROUND: Aptamers refer to the artificially synthesized nucleic acid sequences (DNA/RNA) that can bind to a wide range of targets with high affinity and specificity, which are generally generated from systematic evolution of ligands by exponential enrichment (SELEX). As a novel method of aptamers screening, whole-cell-SELEX (WC-SELEX) has gained more and more attention in many fields such as biomedicine, analytical chemistry, and molecular diagnostics due to its ability to screen multiple potential aptamers without knowing the detailed structural information of target molecules. METHODS AND RESULTS: In recent years, with the deepening of research on application of aptamers, the traditional WC-SELEX cannot meet the practical application because of long experimental period, complicated operation process and low specificity, etc. Therefore, the development of more efficient methods for screening aptamer is always on the road. This paper summarizes the current research status of WC-SELEX for bacteria, parasites and animal cells, and reviews the latest advances of WC-SELEX techniques that are dependent on novel instruments, materials and microelectronics, including fluorescence-activated cell sorting-assisted SELEX, three-dimensional assisted WC-SELEX, and microfluidic chip system-assisted WC-SELEX. In addition, the application of aptamers targeting cells was discussed. CONCLUSION: Taken together, this review is aimed at providing a reference for WC-SELEX selection and application of aptamer targeting cells.


Assuntos
Aptâmeros de Nucleotídeos , Técnica de Seleção de Aptâmeros , Animais , Aptâmeros de Nucleotídeos/química , Citometria de Fluxo , Ligantes , Técnica de Seleção de Aptâmeros/métodos
11.
Environ Res ; 212(Pt C): 113443, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35550809

RESUMO

In the marine environment, the interactions among various species based on chemical signals play critical roles in influencing microbial structure and function. Quorum sensing (QS), the well-known signal-dependent communication autoinducer, is an important regulator in complex microbial communities. Here, we explored the QS gene profiles of phycosphere bacteria during a microcosmic phytoplankton bloom using metagenomic sequence data. More than fifteen subtypes of QS systems and 211,980 non-redundant amino acid sequences were collected and classified for constructing a hierarchical quorum-sensing database. The abundance of the various QS subtypes varied at different bloom stages and showed a strong correlation with phycosphere microorganisms. This suggested that QS is involved in regulating the phycosphere microbial succession during an algal bloom. A neutral community model revealed that the QS functional gene community assemblies were driven by stochastic processes. Co-occurrence model analysis showed that the QS gene networks of phycospheric microbes had similar topological structure and functional composition, which is a potential cornerstone for maintaining signal communication and population stabilization among microorganisms. Overall, QS systems have a strong relationship with the development of algal blooms and participate in regulating algal-associated microbial communities as chemical signals. This research reveals the chemical and ecological behavior of algal symbiotic bacteria and expands the current understanding of microbial dynamics in marine algal blooms.


Assuntos
Microbiota , Percepção de Quorum , Bactérias/metabolismo , Eutrofização , Fitoplâncton/genética
12.
Phys Chem Chem Phys ; 23(2): 1627-1638, 2021 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-33410842

RESUMO

Through the first-principles density functional theory and the phonon Boltzmann transport equation, we investigated the phonon transport characteristics inside 1T-TiSe2. The calculation results of the lattice thermal conductivity (κl) show that the κl of TiSe2 is extremely low (1.28 W (m K)-1, 300 K) and decreases with the shrinkage of the sample size. Moreover, the results also prove the isotropic nature of thermal transport. By decomposing the contribution of the thermal conductivity according to the frequency, the κl of the single-layer TiSe2 is primarily attributed to the acoustic phonons and a small portion of optical phonons, with the frequency range of 0-4.5 THz. The calculation of the scattering rate further illustrates the competition of different scattering modes in this frequency range to verify the change in thermal conductivity of different sample sizes. The high scattering rate and low group velocity lead to the low thermal conductivity of the optical phonon mode in TiSe2. In addition, reducing the size of the system can significantly limit the thermal conductivity by eliminating the contribution of long mean free path phonons. When the characteristic length of the single-layer TiSe2 is about 14.92 nm, κl reduces to half. Our results also show that TiSe2 has an extremely high Grüneisen parameter (about 2.62). Further decomposition of the three-phonon scattering phase space and scattering rate demonstrates that in the range 0-4.5 THz, the absorption process is the main conversion form of phonons. We conclude that, due to the high Grüneisen parameter, the high anharmonicity in TiSe2 leads to the extremely low κl. This study provides κl related to the temperature, frequency, and MFP, and deeply discusses the phonon transport in TiSe2, which has great significance to further adjust the thermal conductivity to develop highly efficient thermoelectric materials and promote the application of devices based on TiSe2.

13.
Med Sci Monit ; 26: e922980, 2020 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-32703926

RESUMO

BACKGROUND Colorectal cancer (CRC), the most common gastrointestinal cancer, is associated with high mortality rates. Enolase is a major enzyme present in the glycolytic pathway. However, the functional significance of the enolase (ENO) gene family in the pathogenesis of CRC has been unclear. MATERIAL AND METHODS The data associated with 438 CRC patients from The Cancer Genome Atlas database were extracted for analysis. Survival analyses with Cox regression was performed to construct a prognostic signature. We investigated the processes that underlies the correlation between ENO genes and overall survival (OS) using gene set enrichment analysis (GSEA). We then developed a connectivity map to identify candidate target drugs for CRC. RESULTS The multivariate survival analysis showed that low expression of ENO2 and ENO3 had a significant correlation with longer OS. The joint-effects survival analysis indicated that the combined low expression of ENO2 and ENO3 was highly correlated with favorable OS. As indicated by the gene set enrichment analysis (GSEA), the ENO gene is involved in various biological pathways and has multiple roles. Potential pharmacological targets of ENO2 and ENO3 were constructed as well. CONCLUSIONS Low expression levels of both ENO2 and ENO3 were linked to a positive prognosis for CRC. Both ENO2 and ENO3 show promise as prognostic biomarkers for colon cancer patients.


Assuntos
Neoplasias do Colo/genética , Fosfopiruvato Hidratase/genética , Biomarcadores Tumorais/genética , Neoplasias do Colo/enzimologia , Neoplasias do Colo/mortalidade , Bases de Dados Genéticas , Feminino , Expressão Gênica , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Masculino , Prognóstico , Modelos de Riscos Proporcionais , Análise de Sobrevida , Resultado do Tratamento
14.
Biochem Biophys Res Commun ; 519(1): 113-120, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31474334

RESUMO

Gastric cancer (GC) is still a major lethal gastrointestinal tumor. In this study, we clarified that RAB13, which is a member of Rab GTPase family and responsible for cargos delivery between the Golgi and the plasma membrane, plays critical roles in the proliferation and the chemotherapeutic resistance in GC cells. Analyzing RAB13 expression in GC specimens, we found that its mRNA level was higher in cancerous tissues compared with normal counterparts and this increase was further associated with malignant progression of GC. Moreover, increased RAB13 indicated poor overall survival (OS) and progression free survival (PFS) in GC patients. We then found that deletion of RAB13 inhibited the proliferation and promoted the apoptosis in AGS and NCI-N87 cells, the impairments of viability which was due to reduced amount of RAB13 anchoring the plasma membrane and attenuated cellular response to EGF treatment and the activation of downstream Akt/ERK/mTOR signaling pathways accordingly. Moreover, in vitro experiments showed that RAB13 deletion enhanced the sensitization of AGS and NCI-N87 cells toward cisplatin (CDDP) and 5-fluorouracil (5-FU) treatment respectively. Together, these data demonstrate that RAB13 promotes the proliferation and confers CDDP and 5-FU resistance to GC cells, which provides experimental support to target this protein in future clinical practice.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais/metabolismo , Cisplatino/farmacologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fluoruracila/farmacologia , Neoplasias Gástricas/tratamento farmacológico , Proteínas rab de Ligação ao GTP/metabolismo , Biomarcadores Tumorais/análise , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Biologia Computacional , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Neoplasias Gástricas/metabolismo , Neoplasias Gástricas/patologia , Células Tumorais Cultivadas , Proteínas rab de Ligação ao GTP/análise , Proteínas rab de Ligação ao GTP/deficiência
15.
Appl Environ Microbiol ; 85(15)2019 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-31126952

RESUMO

Given the ecological significance of microorganisms in algal blooming events, it is critical to understand the mechanisms regarding their distribution under different conditions. We tested the hypothesis that microbial community succession is strongly associated with algal bloom stages, and that the assembly mechanisms are cocontrolled by deterministic and stochastic processes. Community structures and underlying ecological processes of microbial populations (attached and free-living bacteria) at three algal bloom stages (pre-, during, and postbloom) over a complete dinoflagellate Scrippsiella trochoidea bloom were investigated. Both attached and free-living taxa had a strong response to the bloom event, and the latter was more sensitive than the former. The contribution of environmental parameters to microbial variability was 40.2%. Interaction analysis showed that complex positive or negative correlation networks exist in phycosphere microbes. These relationships were the potential drivers of mutualist and competitive interactions that impacted bacterial succession. Null model analysis showed that the attached bacterial community primarily exhibited deterministic processes at pre- and during-bloom stages, while dispersal-related processes contributed to a greater extent at the postbloom stage. In the free-living bacterial community, homogeneous selection and dispersal limitation dominated in the initial phase, which gave way to more deterministic processes at the two later stages. Relative contribution analyses further demonstrated that the community turnover of attached bacteria was mainly driven by environmental selection, while stochastic factors had partial effects on the assembly of free-living bacteria. Taken together, these data demonstrated that a robust link exists between bacterioplankton community structure and bloom progression, and phycosphere microbial succession trajectories are cogoverned by both deterministic and random processes.IMPORTANCE Disentangling the mechanisms shaping bacterioplankton communities during a marine ecological event is a core concern for ecologists. Harmful algal bloom (HAB) is a typical ecological disaster, and its formation is significantly influenced by alga-bacterium interactions. Microbial community shifts during the HAB process are relatively well known. However, the assembly processes of microbial communities in an HAB are not fully understood, especially the relative influences of deterministic and stochastic processes. We therefore analyzed the relative contributions of deterministic and stochastic processes during an HAB event. Both free-living and attached bacterial groups had a dramatic response to the HAB, and the relative importance of determinism versus stochasticity varied between the two bacterial groups at various bloom stages. Environmental factors and biotic interactions were the main drivers impacting the microbial shift process. Our results strengthen the understanding of the ecological mechanisms controlling microbial community patterns during the HAB process.


Assuntos
Organismos Aquáticos/isolamento & purificação , Dinoflagellida/isolamento & purificação , Proliferação Nociva de Algas , Microbiota
16.
BMC Cancer ; 19(1): 583, 2019 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-31200687

RESUMO

BACKGROUND: An accurate, reproducible, and comfortable immobilization device is essential for stereotactic radiotherapy (SBRT) in patients with lung cancer. This study compared thermoplastic masks (TMP) and vacuum cushion (VCS) system to assess the differences in interfraction and intrafraction setup accuracy and the impact of body mass index (BMI) with respect to the immobilization choice. METHODS: This retrospective study was conducted on patients treated with lung SBRT between 2012 and 2015 at the Zhejiang cancer hospital. The treatment setup accuracy was analyzed in 121 patients. A total of 687 cone beam computed tomography (CBCT) scans before treatment and 126 scans after treatment were recorded to determine the uncertainties, and plan target volume margins. Data were further stratified and analyzed by immobilization methods and patients' BMI. The t-test (Welch) was used to assess the differences between the two immobilization systems when stratified by the patients' BMI. RESULTS: For patients with BMI ≥ 24, the mean displacements for the TMP and VCS systems were 1.4 ± 1.2 vs. 2.4 ± 2.0 mm at medial-lateral (ML) direction (p < 0.001); 2.0 ± 1.9 vs. 2.0 ± 1.9 mm at cranial-caudal (CC) direction (p = 0.917); and 2.4 ± 1.4 vs. 2.6 ± 2.1 mm at anterior-posterior (AP) direction, (p = 0.546). The rate of acceptable errors increased dramatically when immobilized by TMP. In the case of patients with BMI < 24, the mean displacements for the TMP and VCS systems were 1.8 ± 1.4 vs. 2.1 ± 1.8 mm at ML direction (p = 0.098); 2.9 ± 2.3 vs. 2.2 ± 2.2 mm at CC direction (p = 0.001); and 1.8 ± 1.8 vs. 2.3 ± 2.0 mm at CC direction, (p = 0.006). The proportion of acceptable errors increased after immobilization by VCS. No difference was detected in the intrafraction setup error by different immobilization methods. CONCLUSIONS: The immobilization choice of SBRT for lung tumors depends on the BMI of the patients. For patients with BMI ≥ 24, TMP offers a better reproducibility with significantly less interfractional setup displacement than VCS, resulting in fewer CBCT scans. However, VCS may be preferred over TMP for the patients with BMI < 24. Therefore, an optimal immobilization system needs to be considered in different BMI groups for lung SBRT.


Assuntos
Índice de Massa Corporal , Neoplasias Pulmonares/radioterapia , Radiocirurgia/métodos , Idoso , Carcinoma Pulmonar de Células não Pequenas/radioterapia , Tomografia Computadorizada de Feixe Cônico , Tomografia Computadorizada Quadridimensional , Humanos , Posicionamento do Paciente , Planejamento da Radioterapia Assistida por Computador/métodos , Estudos Retrospectivos
17.
Mol Cell Probes ; 43: 72-79, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30419277

RESUMO

Frequent outbreaks of toxic algal blooms devastate marine ecosystems, marine fisheries, and public health. Monitoring toxic algae is crucial to reduce losses caused by imminent algal blooms. However, traditional detection techniques relying on morphological examination are tedious and time-consuming. Therefore, the development of convenient strategies to detect toxin-producing microalgae is necessary. In this study, a novel method for the rapid, sensitive detection of Amphidinium carterae by loop-mediated isothermal amplification (LAMP) combined with a chromatographic lateral-flow dipstick (LFD) was established. The partial internal transcribed spacer gene was PCR amplified, cloned, and sequenced to design four LAMP primers and a detection probe for A. carterae detection. The LAMP detection conditions were optimized, and the optimum parameters were determined to be the following: dNTP concentration, 1.2 mM; betaine concentration, 1.2 M; magnesium ion concentration, 8 mM; ratio of inner primer to outer primer, 8:1; amplification temperature, 59 °C; and amplification time, 60 min. The specificity of LAMP-LFD was confirmed by cross-reactivity tests with other algal species. LAMP-LFD was 100 times more sensitive than regular PCR and similarly sensitive as LAMP and SYBR Green I. LAMP-LFD can be completed within 70 min and did not require special detection equipment. The convenience of the established LAMP-LFD assay was further validated by tests with simulated field-water samples. In conclusion, the developed LAMP-LFD assay can be used as a reliable and simple method of detecting A. carterae.


Assuntos
Cromatografia/métodos , Microalgas/genética , Microalgas/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Reologia , Sequência de Bases , Sensibilidade e Especificidade
18.
Microb Ecol ; 76(3): 592-609, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29442157

RESUMO

A central goal in marine microecology is to understand the ecological factors shaping spatiotemporal microbial patterns and the underlying processes. We hypothesized that abiotic and/or biotic interactions are probably more important for explaining the distribution patterns of marine bacterioplankton than environmental filtering. In this study, surface seawater samples were collected about 7000 miles from the Mediterranean Sea, transecting the North Atlantic Ocean, to the Brazilian marginal sea. In bacterial biosphere, SAR11, SAR86, Rhodobacteraceae, and Rhodospiriaceae were predominant in the Mediterranean Sea; Prochlorococcus was more frequent in Atlantic Ocean; whereas in the Brazilian coastal sea, the main bacterial members were Synechococcus and SAR11. With respect to archaea, Euryarchaeota were predominant in the Atlantic Ocean and Thaumarchaeota in the Mediterranean Sea. With respect to the eukaryotes, Syndiniales, Spumellaria, Cryomonadida, and Chlorodendrales were predominant in the open ocean, while diatoms and microzooplankton were dominant in the coastal sea. Distinct clusters of prokaryotes and eukaryotes displayed clear spatial heterogeneity. Among the environmental parameters measured, temperature and salinity were key factors controlling bacterial and archaeal community structure, respectively, whereas N/P/Si contributed to eukaryotic variation. The relative contribution of environmental parameters to the microbial distribution pattern was 45.2%. Interaction analysis showed that Gammaproteobacteria, Alphaproteobacteria, and Flavobacteriia were the keystone taxa within the positive-correlation network, while Thermoplasmata was the main contributor in the negative-correlation network. Our study demonstrated that microbial communities are co-governed by environmental filtering and biotic interactions, which are the main deterministic driving factors modulating the spatiotemporal patterns of marine plankton synergistically at the regional or global levels.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Biodiversidade , Água do Mar/microbiologia , Archaea/classificação , Archaea/genética , Archaea/crescimento & desenvolvimento , Oceano Atlântico , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , Brasil , Mar Mediterrâneo , Filogenia , Água do Mar/química
20.
Contemp Oncol (Pozn) ; 21(1): 35-41, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28435396

RESUMO

AIM OF THE STUDY: To investigate the effects of P27RF-Rho on hepatocellular carcinoma (HCC) cell growth and explore the possibility of using it as a novel therapeutic target for liver cancer treatment. MATERIAL AND METHODS: P27RF-Rho in HCC cells was silenced by lentivirus-mediated RNA interference, and the silencing effect was verified by RT-PCR. Cell proliferation was determined by MTT and clone formation assay. Cell cycle phase and apoptosis were detected through FACS. The expression level of cell growth, apoptosis, and metastasis associated genes was detected by quantitative PCR. RESULTS: Lentivirus-mediated P27RF-Rho knockdown inhibited HCC cell growth and clone formation. P27RF-Rho silence induced cell cycle arrest and apoptosis. The mRNA level of genes associated with cell cycle, apoptosis, and invasion also significantly altered after P27RF-Rho knockdown. Cyclin A, CDK2, BCL-2, and MMP-9 were down-regulated. P27 and Bax were up-regulated. CONCLUSIONS: P27RF-Rho knockdown inhibits HCC cell growth, and P27RF-Rho is probably a promising target for HCC treatment.

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