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1.
Front Genet ; 13: 891665, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35711928

RESUMO

Tumor metastasis and invasion are the main impediments to lung adenocarcinoma successful treatment. Previous studies demonstrate that chemotherapeutic agents can elevate the malignancy of cancer cells other than their therapeutic effects. In this study, the effects of transient low-dose cisplatin treatment on the malignant development of lung adenocarcinoma cells (A549) were detected, and the underlying epigenetic mechanisms were investigated. The findings showed that A549 cells exhibited epithelial-mesenchymal transition (EMT)-like phenotype along with malignant progression under the transient low-dose cisplatin treatment. Meanwhile, low-dose cisplatin was found to induce contactin-1 (CNTN-1) upregulation in A549 cells. Subsequently, we found that further overexpressing CNTN-1 in A549 cells obviously activated the EMT process in vitro and in vivo, and caused malignant development of A549 cells in vitro. Taken together, we conclude that low-dose cisplatin can activate the EMT process and resulting malignant progression through upregulating CNTN-1 in A549 cells. The findings provided new evidence that a low concentration of chemotherapeutic agents could facilitate the malignancy of carcinoma cells via activating the EMT process other than their therapeutic effects.

2.
Cell Death Differ ; 29(10): 2070-2088, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35430615

RESUMO

The proper orientation of centrosome and spindle is essential for genome stability; however, the mechanism that governs these processes remains elusive. Here, we demonstrated that polo-like kinase 1 (Plk1), a key mitotic kinase, phosphorylates residue Thr76 in VCP/p97 (an AAA-ATPase), at the centrosome from prophase to anaphase. This phosphorylation process recruits VCP to the centrosome and in this way, it regulates centrosome orientation. VCP exhibits strong co-localization with Eg5 (a mitotic kinesin motor), at the mitotic spindle, and the dephosphorylation of Thr76 in VCP is required for the enrichment of both VCP and Eg5 at the spindle, thus ensuring proper spindle architecture and chromosome segregation. We also showed that the phosphatase, PTEN, is responsible for the dephosphorylation of Thr76 in VCP; when PTEN was knocked down, the normal spread of VCP from the centrosome to the spindle was abolished. Cryo-EM structures of VCPT76A and VCPT76E, which represent dephosphorylated and phosphorylated states of VCP, respectively, revealed that the Thr76 phosphorylation modulates VCP by altering the inter-domain and inter-subunit interactions, and ultimately the nucleotide-binding pocket conformation. Interestingly, the tumor growth in nude mice implanted with VCPT76A-reconstituted cancer cells was significantly slower when compared with those implanted with VCPWT-reconstituted cancer cells. Collectively, our findings demonstrate that the phosphorylation and dephosphorylation switch of VCP regulates the architecture of centrosome and spindle for faithful chromosome segregation.


Assuntos
Cinesinas , PTEN Fosfo-Hidrolase , Animais , Proteínas de Ciclo Celular/metabolismo , Centrossomo/metabolismo , Células HeLa , Humanos , Cinesinas/genética , Camundongos , Camundongos Nus , Mitose , Nucleotídeos/metabolismo , PTEN Fosfo-Hidrolase/genética , Fosforilação , Fuso Acromático/metabolismo , Proteína com Valosina/genética , Proteína com Valosina/metabolismo
3.
Emerg Microbes Infect ; 10(1): 1418-1428, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34176434

RESUMO

Chlamydia psittaci infection in humans, also known as psittacosis, is usually believed to be an uncommon disease which mainly presents as community-acquired pneumonia (CAP). It is usually sporadic, but outbreaks of infection may occasionally occur. In outbreaks, diagnosis and investigations were usually hampered by the non-specificity of laboratory testing methods to identify C. psittaci. In this study, we use metagenomic next-generation sequencing (mNGS) in the diagnosis of a family outbreak of psittacosis under COVID-19. Three members of an extended family of 6 persons developed psittacosis with pneumonia and hepatic involvement with common symptoms of fever and weakness. Two newly purchased pet parrots, which had died successively, were probably the primary source of infection. Imagings show lung consolidations and infiltrates, which are difficult to be differentiated from CAP caused by other common pathogens. mNGS rapidly identified the infecting agent as C. psittaci within 48 h. The results of this work suggest that there are not characteristic clinical manifestations and imagings of psittacosis pneumonia which can differentiate from CAP caused by other pathogens. The use of mNGS can improve accuracy and reduce the delay in the diagnosis of psittacosis especially during the outbreak, which can shorten the course of the disease control. Family outbreak under COVID-19 may be related to the familial aggregation due to the epidemic. To our knowledge, this is the first reported family outbreak of psittacosis in China, and the first reported psittacosis outbreak identified by the method of mNGS in the world.


Assuntos
Chlamydophila psittaci/genética , Família , Sequenciamento de Nucleotídeos em Larga Escala , Metagenômica , Pneumonia/microbiologia , Psitacose/diagnóstico por imagem , Adulto , Idoso , Animais , COVID-19/epidemiologia , China/epidemiologia , Chlamydophila psittaci/isolamento & purificação , Surtos de Doenças , Feminino , Humanos , Masculino , Metagenoma , Pessoa de Meia-Idade , Papagaios/microbiologia , Pneumonia/diagnóstico por imagem , Psitacose/microbiologia , Psitacose/transmissão , Estudos Retrospectivos , Tomografia Computadorizada por Raios X
4.
Environ Sci Pollut Res Int ; 27(3): 2926-2934, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31838688

RESUMO

To screen out plants with hyperaccumulation of heavy metals and explore the effects of root exudates on the phytoremediation in contaminated soils. The germination rates of five plants including Lolium perenne L. (L. perenne), Sorghum sudanense (Piper) Stapf. (S. sudanense), Pennisetum alopecuroides (L.) Spreng. (P. alopecuroides), Medicago sativa L. (M. sativa), and Trifolium repens L. (T. repens) in different concentrations of cadmium ion solution (0-100 mg/kg) were determined. The growth adaptability of these five plants under conditions of contaminated soils with the above cadmium ion concentrations was also evaluated. S. sudanense and P. alopecuroides had higher germination rates and better growth than the three other plants and were selected as the latter experimental varieties. The activation amounts of cadmium ion in soils were measured using AAS in the presence of three types of root secretions (citric acid, glycine, and maltose) with different concentrations (10-500 mmol/L). The activation amounts decrease in the following order: citric acid > glycine > maltose. The effect of these three root exudates on the removal of cadmium-contaminated soils in combination with S. sudanense and P. alopecuroides was also tested. For S. sudanense and P. alopecuroides, the maximum biomass and removal rate reaches the maximum at 100 mmol/L of citric acid. Conversely, low concentrations (approximately 10-50 mmol/L) of glycine and maltose are more effective for plant growth and phytoremediation. The addition of citric acid at 100 mmol/L and approximately 10-50 mmol/L of glycine and maltose can effectively promote the transfer of cadmium ion from roots to leaves and the accumulation of cadmium ion in leaves.


Assuntos
Cádmio/análise , Recuperação e Remediação Ambiental/métodos , Metais Pesados , Poluentes do Solo , Biodegradação Ambiental , Raízes de Plantas , Solo
5.
Mediators Inflamm ; 2019: 4927430, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31073274

RESUMO

Asthma is characterized by airway inflammation and mucus hypersecretion. Curcumin possessed a potent anti-inflammatory property involved in the PPARγ-dependent NF-κB signaling pathway. Then, the aim of the current study was to explore the value of curcumin in asthmatic airway inflammation and mucus secretion and its underlying mechanism. In vivo, mice were sensitized and challenged by ovalbumin (OVA) to induce chronic asthma. Airway inflammation and mucus secretion were analyzed. In vitro, BEAS-2B cells were obtained. MCP-1, MUC5AC, and PPARγ expression and the phosphorylation of NF-κB p65 and NF-κB p65 DNA-binding activity were measured in both the lungs and BEAS-2B cells. shRNA-PPARγ was used to knock down PPARγ expression. We found that OVA-induced airway inflammation and mucus hypersecretion in mice, OVA and IL-4-induced upregulation of MCP-1 and MUC5AC, suppression of PPARγ, and activation and translocation of NF-κB p65 were notably improved by curcumin both in vivo and in vitro. Our data also showed that these effects of curcumin were significantly abrogated by shRNA-PPARγ. Taken together, our results indicate that curcumin attenuated OVA-induced airway inflammation and mucus hypersecretion in mice and suppressed OVA- and IL-4-induced upregulation of MCP-1 and MUC5AC both in vivo and in vitro, most likely through a PPARγ-dependent NF-κB signaling pathway.


Assuntos
Asma/tratamento farmacológico , Curcumina/uso terapêutico , NF-kappa B/metabolismo , PPAR gama/metabolismo , Transdução de Sinais/efeitos dos fármacos , Animais , Asma/induzido quimicamente , Western Blotting , Linhagem Celular , Humanos , Interleucina-13/metabolismo , Interleucina-4/metabolismo , Interleucina-5/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Ovalbumina/toxicidade , RNA Interferente Pequeno/genética , Fator de Necrose Tumoral alfa/metabolismo
6.
Langmuir ; 33(9): 2378-2386, 2017 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-28178781

RESUMO

The inhibitory effects of CdTe/ZnS quantum dots (QDs) modified with 3-mercaptopropionic acid (negatively charged) or cysteamine (positively charged) on the metabolic activity of Escherichia coli were investigated using biological microcalorimetry. Results show that the inhibitory ratio of positive QDs is higher than that of negative QDs. Transmission electron microscopy images indicate that QDs are prone to be adsorbed on the surface of E. coli. This condition disturbs the membrane structure and function of E. coli. Fluorescence anisotropy results demonstrate that positive QDs show a significant increase in the membrane fluidity of E. coli and dipalmitoylphosphatidylcholine (DPPC) model membrane. Furthermore, fluorescence anisotropy values of DPPC membrane in the gel phase decreased upon the addition of positive QDs. By contrast, anisotropy values in the liquid-crystalline phase are almost constant. The change in membrane fluidity is associated with the increased permeability of the membrane. Finally, the kinetics of dye leakage from liposomes demonstrate that the surface charge of QDs is crucial to the interaction between QDs and membrane.


Assuntos
Compostos de Cádmio/farmacologia , Membrana Celular/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Pontos Quânticos/química , Sulfetos/farmacologia , Telúrio/farmacologia , Compostos de Zinco/farmacologia , Compostos de Cádmio/química , Membrana Celular/química , Escherichia coli/citologia , Escherichia coli/crescimento & desenvolvimento , Microscopia Eletrônica de Transmissão , Tamanho da Partícula , Sulfetos/química , Propriedades de Superfície , Telúrio/química , Compostos de Zinco/química
7.
Biochem Biophys Res Commun ; 473(4): 1229-1234, 2016 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-27079235

RESUMO

Autophagy plays a crucial role in the progress of Mycobacterium tuberculosis (MTB) infection. Recently, MTB enhanced intracellular survival (EIS) protein was reported to be secreted from MTB cells and linked to the inhibition of autophagy and the intracellular persistence of the pathogen. Here, we investigated the mechanism of EIS-mediated inhibition of autophagy in a human phorbol myristate acetate (PMA)-treated THP-1 cell line as well as in murine macrophages. We confirmed that the presence of EIS led to the inhibition of rapamycin (Rapa)-induced autophagy, while IL-10 gene expression was increased and Akt/mTOR/p70S6K pathway was activated during the process. IL-10 gene silencing led to a significant recovery of EIS-mediated autophagy suppression and decreased activity of the Akt/mTOR/p70S6K pathway. IL-10 promoter activity was unaffected by EIS. Remarkably, EIS increased the acetylation level of histone H3 (Ac-H3), which binds to the SP1 and STAT3 region of the human IL-10 gene promoter sequence. Thus, EIS protein possibly increased IL-10 expression through the regulation of Ac-H3 of its promoter. Our data demonstrated that one possible mechanism of the MTB evasion of autophagy is that the EIS protein up-regulates IL-10 via Ac-H3 and thus activates Akt/mTOR/p70S6K pathway.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Regulação Bacteriana da Expressão Gênica/fisiologia , Histonas/metabolismo , Interleucina-10/metabolismo , Macrófagos/microbiologia , Mycobacterium tuberculosis/fisiologia , Acetilação , Acetiltransferases , Autofagia/fisiologia , Mycobacterium tuberculosis/citologia , Regulação para Cima/fisiologia
8.
ISME J ; 10(6): 1527-39, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26943622

RESUMO

Predicting the dynamics of community composition and functional attributes responding to environmental changes is an essential goal in community ecology but remains a major challenge, particularly in microbial ecology. Here, by targeting a model system with low species richness, we explore the spatial distribution of taxonomic and functional structure of 40 acid mine drainage (AMD) microbial communities across Southeast China profiled by 16S ribosomal RNA pyrosequencing and a comprehensive microarray (GeoChip). Similar environmentally dependent patterns of dominant microbial lineages and key functional genes were observed regardless of the large-scale geographical isolation. Functional and phylogenetic ß-diversities were significantly correlated, whereas functional metabolic potentials were strongly influenced by environmental conditions and community taxonomic structure. Using advanced modeling approaches based on artificial neural networks, we successfully predicted the taxonomic and functional dynamics with significantly higher prediction accuracies of metabolic potentials (average Bray-Curtis similarity 87.8) as compared with relative microbial abundances (similarity 66.8), implying that natural AMD microbial assemblages may be better predicted at the functional genes level rather than at taxonomic level. Furthermore, relative metabolic potentials of genes involved in many key ecological functions (for example, nitrogen and phosphate utilization, metals resistance and stress response) were extrapolated to increase under more acidic and metal-rich conditions, indicating a critical strategy of stress adaptation in these extraordinary communities. Collectively, our findings indicate that natural selection rather than geographic distance has a more crucial role in shaping the taxonomic and functional patterns of AMD microbial community that readily predicted by modeling methods and suggest that the model-based approach is essential to better understand natural acidophilic microbial communities.


Assuntos
Bactérias/classificação , Água Subterrânea/microbiologia , Consórcios Microbianos , Ácidos , Bactérias/efeitos dos fármacos , Bactérias/genética , Bactérias/metabolismo , Biodiversidade , China , Análise por Conglomerados , Ecologia , Ambientes Extremos , Concentração de Íons de Hidrogênio , Mineração , Nitrogênio/metabolismo , Filogenia , RNA Ribossômico 16S/química , RNA Ribossômico 16S/genética , Águas Residuárias/química , Águas Residuárias/microbiologia
9.
Eur J Cancer Prev ; 25(4): 255-8, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-26061994

RESUMO

Autophagy acts as a double-edged sword in cancer. Over the years, there has been growing evidence of the involvement of autophagy-related genes (ATGs) in the etiology and progression of cancer. Importantly, lung cancer is one of the most common cancers and represents the leading cause of cancer-related mortality in developing countries. The genomic variant has emerged as an important factor in the risk of lung cancer. Here, we hypothesize that the intron single-nucleotide polymorphism (SNP) of rs807185 in ATG4A is associated with the risk of lung cancer. In this case-control study, we genotyped the SNP rs807185 with PCR-restriction fragment length polymorphism. Our data suggest that the variant A allele frequency of rs807185 in controls is higher than that in cases (37.7 vs. 24.9%, P=0.006). The adjusted odds ratio is 1.989 (95% confidence interval 1.223-3.236). Compared with the wild T allele, the variant A allele of rs807185 in ATG4A is associated with a decreased risk of lung cancer (adjusted odds ratio=0.605, 95% confidence interval 0.456-0.803, P<0.001). Furthermore, stratified analysis in a recessive model suggests that the homozygous variant genotype (AA) of rs807185 could decrease the risk of lung cancer in smoking or nonsmoking groups. In conclusion, the variant of intron SNP rs807185 in ATG4A is associated significantly with a decreased risk of lung cancer in a southwest Chinese population. The results show that the variant rs807185 of ATG4A might be a protective factor for lung cancer.


Assuntos
Povo Asiático/genética , Proteínas Relacionadas à Autofagia/genética , Cisteína Endopeptidases/genética , Íntrons , Neoplasias Pulmonares/genética , Polimorfismo de Nucleotídeo Único , Adenocarcinoma/epidemiologia , Adenocarcinoma/genética , Adenocarcinoma/patologia , Idoso , Carcinoma Pulmonar de Células não Pequenas/epidemiologia , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , China/epidemiologia , Feminino , Seguimentos , Predisposição Genética para Doença , Genótipo , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Carcinoma de Pequenas Células do Pulmão/epidemiologia , Carcinoma de Pequenas Células do Pulmão/genética , Carcinoma de Pequenas Células do Pulmão/patologia
10.
Ultrasound Med Biol ; 41(10): 2677-89, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26119460

RESUMO

Needle entry site localization remains a challenge for procedures that involve lumbar puncture, for example, epidural anesthesia. To solve the problem, we have developed an image classification algorithm that can automatically identify the bone/interspinous region for ultrasound images obtained from lumbar spine of pregnant patients in the transverse plane. The proposed algorithm consists of feature extraction, feature selection and machine learning procedures. A set of features, including matching values, positions and the appearance of black pixels within pre-defined windows along the midline, were extracted from the ultrasound images using template matching and midline detection methods. A support vector machine was then used to classify the bone images and interspinous images. The support vector machine model was trained with 1,040 images from 26 pregnant subjects and tested on 800 images from a separate set of 20 pregnant patients. A success rate of 95.0% on training set and 93.2% on test set was achieved with the proposed method. The trained support vector machine model was further tested on 46 off-line collected videos, and successfully identified the proper needle insertion site (interspinous region) in 45 of the cases. Therefore, the proposed method is able to process the ultrasound images of lumbar spine in an automatic manner, so as to facilitate the anesthetists' work of identifying the needle entry site.


Assuntos
Anestesia Epidural/métodos , Interpretação de Imagem Assistida por Computador/métodos , Vértebras Lombares/diagnóstico por imagem , Reconhecimento Automatizado de Padrão/métodos , Máquina de Vetores de Suporte , Ultrassonografia de Intervenção/métodos , Algoritmos , Feminino , Humanos , Aumento da Imagem/métodos , Gravidez , Punções , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
11.
Arch Oral Biol ; 60(9): 1283-98, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26099663

RESUMO

BACKGROUND: Acacetin (5,7-dihydroxy-40-methoxyflavone), present in safflower seeds, plants, flowers, Cirisium rhinoceros Nakai, has been reported to be able to exert anti-peroxidative, anti-inflammatory, anti-plasmodial, and anti-proliferative activities by inducing apoptosis and blocking the progression of cell cycles. OBJECTIVE AND DESIGN: The objective of this study is to investigate the mechanism of acacetin-induced apoptosis of oral squamous cell carcinoma cell line (HSC-3). RESULTS: Acacetin caused 50% growth inhibition (IC50) of HSC-3 cells at 25µg/mL over 24h in the MTT assay. Apoptosis was characterized by DNA fragmentation and increase of sub-G1 cells and involved activation of caspase-3 and PARP (poly-ADP-ribose polymerase). Maximum caspase-3 activity was observed with 100µg/mL of acacetin for 24h. Caspase-8 and -9 activation cascades mediated the activation of caspase-3. Acacetin caused reduction of Bcl-2 expression leading to an increase of the Bax:Bcl-2 ratio. It also caused a loss of mitochondrial membrane potential that induced release of cytochrome c into the cytoplasm. Pretreatment with casapse-3 (Z-DEVD-FMK), -8 (Z-IETD-FMK), and 9 inhibitor (z-LEHD-fmk) inhibited the acacetin-induced loss of mitochondrial membrane potential and release of cytochrome c. The mitogen-activated protein kinases (MAPKs) were activated by acacetin. Moreover, pretreating the cells with each of the caspase inhibitor or MAPKs specific inhibitors apparently inhibited acacetin-induced cytotoxicity of HSC-3 cells. CONCLUSION: In conclusion, acacetin induce the apoptosis of oral squamous cell carcinoma cell line, which is closely related to its ability to activate the MAPK-mediated signaling pathways with the subsequent induction of a mitochondria- and caspase-dependent mechanism. These results strongly suggest that acacetin might have cancer inhibition and therapeutic potential.


Assuntos
Apoptose/efeitos dos fármacos , Carcinoma de Células Escamosas/tratamento farmacológico , Flavonas/farmacologia , Neoplasias Bucais/tratamento farmacológico , Western Blotting , Carcinoma de Células Escamosas/enzimologia , Caspase 3/metabolismo , Caspase 8/metabolismo , Caspase 9/metabolismo , Ciclo Celular , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Citocromos c/metabolismo , Fragmentação do DNA , Citometria de Fluxo , Humanos , Marcação In Situ das Extremidades Cortadas , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Neoplasias Bucais/enzimologia , Oligopeptídeos/farmacologia , Poli(ADP-Ribose) Polimerases/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Transdução de Sinais
12.
ISME J ; 9(6): 1280-94, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25361395

RESUMO

High-throughput sequencing is expanding our knowledge of microbial diversity in the environment. Still, understanding the metabolic potentials and ecological roles of rare and uncultured microbes in natural communities remains a major challenge. To this end, we applied a 'divide and conquer' strategy that partitioned a massive metagenomic data set (>100 Gbp) into subsets based on K-mer frequency in sequence assembly to a low-diversity acid mine drainage (AMD) microbial community and, by integrating with an additional metatranscriptomic assembly, successfully obtained 11 draft genomes most of which represent yet uncultured and/or rare taxa (relative abundance <1%). We report the first genome of a naturally occurring Ferrovum population (relative abundance >90%) and its metabolic potentials and gene expression profile, providing initial molecular insights into the ecological role of these lesser known, but potentially important, microorganisms in the AMD environment. Gene transcriptional analysis of the active taxa revealed major metabolic capabilities executed in situ, including carbon- and nitrogen-related metabolisms associated with syntrophic interactions, iron and sulfur oxidation, which are key in energy conservation and AMD generation, and the mechanisms of adaptation and response to the environmental stresses (heavy metals, low pH and oxidative stress). Remarkably, nitrogen fixation and sulfur oxidation were performed by the rare taxa, indicating their critical roles in the overall functioning and assembly of the AMD community. Our study demonstrates the potential of the 'divide and conquer' strategy in high-throughput sequencing data assembly for genome reconstruction and functional partitioning analysis of both dominant and rare species in natural microbial assemblages.


Assuntos
Betaproteobacteria/genética , Ecologia , Poluentes Ambientais/química , Mineração , Ácidos , Carbono , Perfilação da Expressão Gênica , Regulação da Expressão Gênica , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Concentração de Íons de Hidrogênio , Metagenômica , Metais Pesados/química , Fixação de Nitrogênio , Estresse Oxidativo , Enxofre/química , Transcriptoma
13.
ISME J ; 9(7): 1579-92, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25535937

RESUMO

The microbial communities in acid mine drainage have been extensively studied to reveal their roles in acid generation and adaption to this environment. Lacking, however, are integrated community- and organism-wide comparative gene transcriptional analyses that could reveal the response and adaptation mechanisms of these extraordinary microorganisms to different environmental conditions. In this study, comparative metagenomics and metatranscriptomics were performed on microbial assemblages collected from four geochemically distinct acid mine drainage (AMD) sites. Taxonomic analysis uncovered unexpectedly high microbial biodiversity of these extremely acidophilic communities, and the abundant taxa of Acidithiobacillus, Leptospirillum and Acidiphilium exhibited high transcriptional activities. Community-wide comparative analyses clearly showed that the AMD microorganisms adapted to the different environmental conditions via regulating the expression of genes involved in multiple in situ functional activities, including low-pH adaptation, carbon, nitrogen and phosphate assimilation, energy generation, environmental stress resistance, and other functions. Organism-wide comparative analyses of the active taxa revealed environment-dependent gene transcriptional profiles, especially the distinct strategies used by Acidithiobacillus ferrivorans and Leptospirillum ferrodiazotrophum in nutrients assimilation and energy generation for survival under different conditions. Overall, these findings demonstrate that the gene transcriptional profiles of AMD microorganisms are closely related to the site physiochemical characteristics, providing clues into the microbial response and adaptation mechanisms in the oligotrophic, extremely acidic environments.


Assuntos
Bactérias/genética , Metagenômica/métodos , Mineração , Acidithiobacillus , Ácidos/metabolismo , Biodiversidade , Microbiologia Ambiental , Concentração de Íons de Hidrogênio
14.
Sci Rep ; 4: 6205, 2014 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-25158668

RESUMO

Evolutionary analysis of microbes at the community level represents a new research avenue linking ecological patterns to evolutionary processes, but remains insufficiently studied. Here we report a relative evolutionary rates (rERs) analysis of microbial communities from six diverse natural environments based on 40 metagenomic samples. We show that the rERs of microbial communities are mainly shaped by environmental conditions, and the microbes inhabiting extreme habitats (acid mine drainage, saline lake and hot spring) evolve faster than those populating benign environments (surface ocean, fresh water and soil). These findings were supported by the observation of more relaxed purifying selection and potentially frequent horizontal gene transfers in communities from extreme habitats. The mechanism of high rERs was proposed as high mutation rates imposed by stressful conditions during the evolutionary processes. This study brings us one stage closer to an understanding of the evolutionary mechanisms underlying the adaptation of microbes to extreme environments.


Assuntos
Evolução Molecular , Interação Gene-Ambiente , Consórcios Microbianos/genética , Microbiologia da Água , Archaea/genética , Bactérias/genética , Análise por Conglomerados , Ecossistema , Genes Arqueais , Genes Bacterianos , Fontes Termais/microbiologia , Interações Microbianas , Taxa de Mutação , Filogenia
15.
Ultrasound Med Biol ; 40(9): 1980-90, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24972502

RESUMO

Ultrasound imaging was used to detect the anatomic structure of lumbar spine from the transverse view, to facilitate needle insertion in epidural anesthesia. The interspinous images that represent proper needle insertion sites were identified automatically with image processing and pattern recognition techniques. On the basis of ultrasound video streams obtained in pregnant patients, the image processing and identification procedure in a previous work was tested and improved. The test results indicate that the pre-processing algorithm performs well on lumbar spine ultrasound images, whereas the classifier is not flexible enough for pregnant patients. To improve the accuracy of identification, we propose a cascading classifier that successfully located the proper needle insertion site on all of the 36 video streams collected from pregnant patients. The results indicate that the proposed image identification procedure is able to identify the ultrasound images of lumbar spine in an automatic manner, so as to facilitate the anesthetists' work to identify the needle insertion point precisely and effectively.


Assuntos
Anestesia Epidural/métodos , Anestesia Obstétrica/métodos , Processamento de Imagem Assistida por Computador/métodos , Reconhecimento Automatizado de Padrão/métodos , Ultrassonografia de Intervenção/métodos , Adulto , Anestesia Epidural/instrumentação , Espaço Epidural/diagnóstico por imagem , Feminino , Humanos , Região Lombossacral/diagnóstico por imagem , Agulhas , Gravidez , Reprodutibilidade dos Testes
16.
Appl Environ Microbiol ; 80(12): 3677-86, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24727268

RESUMO

Recent molecular surveys have advanced our understanding of the forces shaping the large-scale ecological distribution of microbes in Earth's extreme habitats, such as hot springs and acid mine drainage. However, few investigations have attempted dense spatial analyses of specific sites to resolve the local diversity of these extraordinary organisms and how communities are shaped by the harsh environmental conditions found there. We have applied a 16S rRNA gene-targeted 454 pyrosequencing approach to explore the phylogenetic differentiation among 90 microbial communities from a massive copper tailing impoundment generating acidic drainage and coupled these variations in community composition with geochemical parameters to reveal ecological interactions in this extreme environment. Our data showed that the overall microbial diversity estimates and relative abundances of most of the dominant lineages were significantly correlated with pH, with the simplest assemblages occurring under extremely acidic conditions and more diverse assemblages associated with neutral pHs. The consistent shifts in community composition along the pH gradient indicated that different taxa were involved in the different acidification stages of the mine tailings. Moreover, the effect of pH in shaping phylogenetic structure within specific lineages was also clearly evident, although the phylogenetic differentiations within the Alphaproteobacteria, Deltaproteobacteria, and Firmicutes were attributed to variations in ferric and ferrous iron concentrations. Application of the microbial assemblage prediction model further supported pH as the major factor driving community structure and demonstrated that several of the major lineages are readily predictable. Together, these results suggest that pH is primarily responsible for structuring whole communities in the extreme and heterogeneous mine tailings, although the diverse microbial taxa may respond differently to various environmental conditions.


Assuntos
Bactérias/isolamento & purificação , Biodiversidade , Ecossistema , Águas Residuárias/microbiologia , Bactérias/classificação , Bactérias/genética , Concentração de Íons de Hidrogênio , Mineração , Dados de Sequência Molecular , Filogenia , Águas Residuárias/química
17.
Artigo em Inglês | MEDLINE | ID: mdl-25571031

RESUMO

In this paper, we proposed a feature extraction and machine learning method for the classification of ultrasound images obtained from lumbar spine of pregnant patients in the transverse plane. A group of features, including matching values and positions, appearance of black pixels within predefined windows along the midline, are extracted from the ultrasound images using template matching and midline detection. Support vector machine (SVM) with Gaussian kernel is utilized to classify the bone images and interspinous images with optimal separation hyperplane. The SVM is trained with 800 images from 20 pregnant subjects and tested with 640 images from a separate set of 16 pregnant patients. A high success rate (97.25% on training set and 95.00% on test set) is achieved with the proposed method. The trained SVM model is further tested on 36 videos collected from 36 pregnant subjects and successfully identified the proper needle insertion site (interspinous region) on all of the cases. Therefore, the proposed method is able to identify the ultrasound images of lumbar spine in an automatic manner, so as to facilitate the anesthetists' work to identify the needle insertion point precisely and effectively.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Vértebras Lombares/diagnóstico por imagem , Máquina de Vetores de Suporte , Anestesia , Feminino , Humanos , Gravidez , Ultrassonografia
18.
Clin Biochem ; 46(12): 1093-1098, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23665439

RESUMO

OBJECTIVES: Buprenorphine (BUP) is the primary treatment for narcotic addiction, but it is often abused by opioid-dependent patients in many countries. For timely and effective detection and controlling the amount of BUP used in therapy, a rapid and sensitive test is needed. In the present study, we describe the development of test strips using monoclonal antibodies (MAbs) for the detection of BUP. DESIGN AND METHODS: The MAbs were generated from hybridomas, and purified MAbs were used to create colloidal gold-antibody conjugates that were placed in the test strips. RESULTS: The BUP test strips had a limit of detection (LOD) of 12.5 ng/mL and did not cross-react with other drugs tested at physiological levels. CONCLUSIONS: Therefore, this assay has sufficient sensitivity and specificity for BUP detection in urine specimens so that the dosage of BUP given to individuals being treated for opioid dependence can be monitored.


Assuntos
Buprenorfina/urina , Química Clínica/métodos , Fitas Reagentes , Animais , Anticorpos Monoclonais/imunologia , Cromatografia de Afinidade , Eletroforese em Gel de Poliacrilamida , Gravitação , Concentração de Íons de Hidrogênio , Limite de Detecção , Camundongos , Camundongos Endogâmicos BALB C
19.
ISME J ; 7(5): 1038-50, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23178673

RESUMO

A wide array of microorganisms survive and thrive in extreme environments. However, we know little about the patterns of, and controls over, their large-scale ecological distribution. To this end, we have applied a bar-coded 16S rRNA pyrosequencing technology to explore the phylogenetic differentiation among 59 microbial communities from physically and geochemically diverse acid mine drainage (AMD) sites across Southeast China, revealing for the first time environmental variation as the major factor explaining community differences in these harsh environments. Our data showed that overall microbial diversity estimates, including phylogenetic diversity, phylotype richness and pairwise UniFrac distance, were largely correlated with pH conditions. Furthermore, multivariate regression tree analysis also identified solution pH as a strong predictor of relative lineage abundance. Betaproteobacteria, mostly affiliated with the 'Ferrovum' genus, were explicitly predominant in assemblages under moderate pH conditions, whereas Alphaproteobacteria, Euryarchaeota, Gammaproteobacteria and Nitrospira exhibited a strong adaptation to more acidic environments. Strikingly, such pH-dependent patterns could also be observed in a subsequent comprehensive analysis of the environmental distribution of acidophilic microorganisms based on 16S rRNA gene sequences previously retrieved from globally distributed AMD and associated environments, regardless of the long-distance isolation and the distinct substrate types. Collectively, our results suggest that microbial diversity patterns are better predicted by contemporary environmental variation rather than geographical distance in extreme AMD systems.


Assuntos
Bactérias/classificação , Bactérias/isolamento & purificação , Água Subterrânea/microbiologia , Mineração , Bactérias/genética , Betaproteobacteria/genética , Betaproteobacteria/isolamento & purificação , Biodiversidade , China , Filogenia , RNA Ribossômico 16S/genética
20.
Head Neck ; 34(7): 929-36, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22128038

RESUMO

BACKGROUND: An accurate system for predicting the survival of patients with oral squamous cell carcinoma (OSCC) will be useful for deciding appropriate therapies. The prediction accuracy of prediction models can be improved by using molecular biomarkers. We constructed a nomogram for predicting the survival of patients with OSCC using clinical variables and molecular markers. METHODS: Protein 53 (p53), insulin-like growth factor II mRNA-binding protein 3 (IMP3), cyclooxygenase 2 (COX2), and HuR were localized immunohistochemistry in 96 patients with primary OSCC who underwent surgical resection between January 1994 and June 2003 at the Yonsei Dental Hospital in Seoul, Korea. RESULTS: On univariate and multivariate analysis, the expression of IMP3 was significantly associated with the risk of death. P53 was also significantly associated with survival of OSCC in the case of negative IMP3 and the prediction accuracy was improved by including these 2 factors in the prediction model. CONCLUSION: Survival in OSCC can be predicted more accurately by using biomarkers. The constructed nomogram predicted survival after treatment for an individual patient with OSCC, and it can be practically used as a tool to help decide which adjuvant treatment is most appropriate.


Assuntos
Biomarcadores Tumorais/metabolismo , Carcinoma de Células Escamosas/metabolismo , Neoplasias Bucais/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteína Supressora de Tumor p53/metabolismo , Carcinoma de Células Escamosas/mortalidade , Ciclo-Oxigenase 2/metabolismo , Proteínas ELAV/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Neoplasias Bucais/mortalidade , Análise Multivariada , Prognóstico , República da Coreia , Estudos Retrospectivos
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