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1.
Artigo em Inglês | MEDLINE | ID: mdl-38805025

RESUMO

Three psychrophilic bacteria, designated as strains SQ149T, SQ345T, and S1-1T, were isolated from deep-sea sediment from the South China Sea. All three strains were the most closely related to Thalassotalea atypica RZG4-3-1T based on the 16S rRNA gene sequence analysis (similarity ranged from 96.45 to 96.67 %). Phylogenetic analysis based on the 16S rRNA gene and core-genome sequences showed that three strains formed a cluster within the genus Thalassotalea. The average amino acid identity, average nucleotide identity, and digital DNA-DNA hybridization values among the three strains and closest Thalassotalea species were far below the cut-off value recommended for delineating species, indicating they each represented a novel species. All three strains were Gram-stain-negative, rod-shaped, and contained summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c) as the predominant fatty acid, Q-8 as the major respiratory quinone, and phosphatidylethanolamine and phosphatidylglycerol as predominant polar lipids. Based on the genomic, phylogenetic, and phenotypic characterizations, each strain is considered to represent a novel species within the genus Thalassotalea, for which the names Thalassotalea psychrophila sp. nov. (type strain SQ149T=MCCC 1K04231T=JCM 33807T), Thalassotalea nanhaiensis sp. nov. (type strain SQ345T=MCCC 1K04232T=JCM 33808T), and Thalassotalea fonticola sp. nov. (type strain S1-1T=MCCC 1K06879T=JCM 34824T) are proposed.


Assuntos
Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano , Ácidos Graxos , Sedimentos Geológicos , Hibridização de Ácido Nucleico , Filogenia , RNA Ribossômico 16S , Água do Mar , Análise de Sequência de DNA , Sedimentos Geológicos/microbiologia , RNA Ribossômico 16S/genética , DNA Bacteriano/genética , Ácidos Graxos/química , China , Água do Mar/microbiologia
2.
Eur Arch Otorhinolaryngol ; 281(1): 419-425, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37673830

RESUMO

OBJECTIVE: The ultrasonic diagnosis of cervical and facial cystic masses, as well as cases of missed diagnosis and misdiagnosis, was examined, to improve the diagnosis of branchial cleft anomalies. METHODS: A retrospective analysis was conducted on 17 patients with branchial cleft cyst anomalies, including 11 males and 6 females, aged 12-53 years, with an average age of 33 ± 2 years, were unilateral single. All patients who underwent an ultrasound examination and image storage for retrospective analysis, and both longitudinal and transverse sections were scanned to observe the shape, size, boundary, peripheral relationship, and blood flow signal of the masses. All cases were examined with an enhanced CT scan, and pathological reports were generated. RESULTS: Among the 17 cases of branchial cleft anomalies, 15 cases were branchial cleft cysts, while one case involved fistula formation and one case involved sinus tract formation. Based on the type of branchial cleft, the first, second, and third cysts were classified in 4, 12, and 1 case, respectively. The sensitivity rate and specificity of ultrasonic diagnosis were 14/17 (82.4%) and 4/6 (66.7%), respectively. Ultrasonic characteristic analysis for the masses can be found in simple cystic masses or hypoechoic masses, most of them are of a regular shape and have a distinct boundary, and almost no blood flow signal. All patients who were misdiagnosed exhibited blood flow signals, including 1 patient with an abundant blood flow signal, 1 patient suspected of having ectopic thyroid with an abnormal function due to the rat-tail sign, 2 patients misdiagnosed as local inflammatory focus, and 1 patient misdiagnosed with tuberculous lymphadenitis. CONCLUSION: Ultrasound has a detection rate of up to 100% for cervical and facial masses, providing a fundamental determination of lesion characteristics and specific guidance for preoperative diagnosis. If the blood flow signals can be identified and carefully considered their peripheral relationship, the diagnostic rate can be improved.


Assuntos
Branquioma , Fístula , Neoplasias de Cabeça e Pescoço , Masculino , Feminino , Humanos , Animais , Ratos , Adulto , Branquioma/diagnóstico por imagem , Branquioma/cirurgia , Estudos Retrospectivos , Região Branquial/diagnóstico por imagem , Região Branquial/cirurgia , Região Branquial/anormalidades , Neoplasias de Cabeça e Pescoço/diagnóstico por imagem , Neoplasias de Cabeça e Pescoço/cirurgia , Fístula/cirurgia , Ultrassonografia
3.
Front Microbiol ; 14: 1291578, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38029070

RESUMO

High hydrostatic pressure (HHP) regulated gene expression is one of the most commonly adopted strategies for microbial adaptation to the deep-sea environments. Previously we showed that the HHP-inducible trimethylamine N-oxide (TMAO) reductase improves the pressure tolerance of deep-sea strain Vibrio fluvialis QY27. Here, we investigated the molecular mechanism of HHP-responsive regulation of TMAO reductase TorA. By constructing torR and torS deletion mutants, we demonstrated that the two-component regulator TorR and sensor TorS are responsible for the HHP-responsive regulation of torA. Unlike known HHP-responsive regulatory system, the abundance of torR and torS was not affected by HHP. Complementation of the ΔtorS mutant with TorS altered at conserved phosphorylation sites revealed that the three sites were indispensable for substrate-induced regulation, but only the histidine located in the alternative transmitter domain was involved in pressure-responsive regulation. Taken together, we demonstrated that the induction of TMAO reductase by HHP is mediated through the TorRS system and proposed a bifurcation of signal transduction in pressure-responsive regulation from the substrate-induction. This work provides novel knowledge of the pressure regulated gene expression and will promote the understanding of the microbial adaptation to the deep-sea HHP environment.

4.
Artigo em Inglês | MEDLINE | ID: mdl-37755238

RESUMO

A novel bacterium, strain QS115T, was isolated from deep-sea sediment collected from the South China Sea at a depth of 1151 m. Phylogenetic analyses based on 16S rRNA gene sequences indicated that QS115T was most closely related to Parasedimentitalea marina W43T, with similarity of 98.21 %. Strain QS115T shared 82.39 % average nucleotide identity, 26.3 % digital DNA-DNA hybridization and 85.32 % average amino acid identity with P. marina W43T. Cells of strain QS115T were Gram-stain-negative, rod-shaped and grew optimally at 10 °C, pH 7.5 and 2 % (w/v) NaCl. The principal fatty acids were summed feature 8 (C18 : 1 ω7c/ω6c), the major respiratory quinone was ubiquinone-10 and predominant polar lipids were diphosphatidylglycerol, phosphatidylethanolamine, glycophospholipid, phosphatidylglycerol and phosphatidylcholine. Polyphasic analyses of physiological and phenotypic characteristics and genomic studies suggested that strain QS115T represents a novel species of the genus Parasedimentitalea, for which the name Parasedimentitalea psychrophila sp. nov. is proposed (type strain QS115T=MCCC 1K04395T=JCM 34219T).


Assuntos
Ácidos Graxos , Fosfolipídeos , Ácidos Graxos/química , Fosfolipídeos/química , Água do Mar/microbiologia , DNA Bacteriano/genética , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Composição de Bases , Técnicas de Tipagem Bacteriana , Ubiquinona/química , Bactérias/genética
5.
Microorganisms ; 11(6)2023 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-37374864

RESUMO

Bioluminescence is a common phenomenon in nature, especially in the deep ocean. The physiological role of bacterial bioluminescence involves protection against oxidative and UV stresses. Yet, it remains unclear if bioluminescence contributes to deep-sea bacterial adaptation to high hydrostatic pressure (HHP). In this study, we constructed a non-luminescent mutant of ΔluxA and its complementary strain c-ΔluxA of Photobacterium phosphoreum ANT-2200, a deep-sea piezophilic bioluminescent bacterium. The wild-type strain, mutant and complementary strain were compared from aspects of pressure tolerance, intracellular reactive oxygen species (ROS) level and expression of ROS-scavenging enzymes. The results showed that, despite similar growth profiles, HHP induced the accumulation of intracellular ROS and up-regulated the expression of ROS-scavenging enzymes such as dyp, katE and katG, specifically in the non-luminescent mutant. Collectively, our results suggested that bioluminescence functions as the primary antioxidant system in strain ANT-2200, in addition to the well-known ROS-scavenging enzymes. Bioluminescence contributes to bacterial adaptation to the deep-sea environment by coping with oxidative stress generated from HHP. These results further expanded our understanding of the physiological significance of bioluminescence as well as a novel strategy for microbial adaptation to a deep-sea environment.

6.
Microorganisms ; 11(3)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36985211

RESUMO

Alteration of respiratory components as a function of pressure is a common strategy developed in deep-sea microorganisms, presumably to adapt to high hydrostatic pressure (HHP). While the electron transport chain and terminal reductases have been extensively studied in deep-sea bacteria, little is known about their adaptations for ATP generation. In this study, we showed that the deep-sea bacterium Photobacterium profundum SS9 exhibits a more pronounced piezophilic phenotype when grown in minimal medium supplemented with glucose (MG) than in the routinely used MB2216 complex medium. The intracellular ATP level varied with pressure, but with opposite trends in the two culture media. Between the two ATPase systems encoded in SS9, ATPase-I played a dominant role when cultivated in MB2216, whereas ATPase-II was more abundant in the MG medium, especially at elevated pressure when cells had the lowest ATP level among all conditions tested. Further analyses of the ΔatpI, ΔatpE1 and ΔatpE2 mutants showed that disrupting ATPase-I induced expression of ATPase-II and that the two systems are functionally redundant in MB2216. Collectively, we provide the first examination of the differences and relationships between two ATPase systems in a piezophilic bacterium, and expanded our understanding of the involvement of energy metabolism in pressure adaptation.

7.
Artigo em Inglês | MEDLINE | ID: mdl-36951905

RESUMO

A novel moderately thermophilic heterotrophic bacterium, designated strain 143-21T, was isolated from a deep-sea hydrothermal chimney sample collected from the Central Indian Ridge at a depth of 2 440 m. Phylogenetic analysis indicated that strain 143-21T belongs to the genus Crassaminicella. It was most closely related to Crassaminicella thermophila SY095T (96.79 % 16S rRNA gene sequence similarity) and Crassaminicella profunda Ra1766HT (96.52 %). Genomic analysis showed that strain 143-21T shares 79.79-84.45 % average nucleotide identity and 23.50-29.20 % digital DNA-DNA hybridization with the species of the genus Crassaminicella, respectively. Cells were rod-shaped, non-motile, Gram-positive-staining. Terminal endospores were observed in stationary-phase cells when strain 143-21T was grown on Thermococcales rich medium. Strain 143-21T was able to grow at 30-60 °C (optimum, 50 °C), pH 6.5-8.5 (optimum, pH 7.0) and in 1.0-7.0 % NaCl (w/v; optimum 2.0 %, w/v). Strain 143-21T utilized fructose, glucose, maltose, mannose, ribose, N-acetyl-d-(+)-glucosamine and casamino acids, as well as amino acids including glutamate, lysine, histidine and cysteine. The main fermentation products from glucose were acetate (2.07 mM), H2 and CO2. It did not reduce elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and Fe (III). The predominant cellular fatty acids were C14 : 0 (48.8 %), C16 : 0 (12.9 %), and summed feature 3 (C16 : 1 ω7c and/or C16 : 1 ω6c; 10.2 %). The major polar lipids were diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylglycerol, as well as two unidentified phospholipids and four unidentified aminolipids. No respiratory quinones were detected. Based on its phylogenetic analysis and physiological characteristics, strain 143-21T is considered to represent a novel species of the genus Crassaminicella, for which the name Crassaminicella indica sp. nov. is proposed. The type strain is strain 143-21T (=DSM 114408T= MCCC 1K06400T).


Assuntos
Ácidos Graxos , Fontes Hidrotermais , Ácidos Graxos/química , Filogenia , RNA Ribossômico 16S/genética , Composição de Bases , Fontes Hidrotermais/microbiologia , Anaerobiose , Análise de Sequência de DNA , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Fosfolipídeos/química , Bactérias Anaeróbias
8.
Mar Genomics ; 65: 100982, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36096633

RESUMO

Gilvimarinus sp. DA14, a putative new species isolated from mangrove sediment in the South China Sea (Beihai, Guangxi province), is an aerobic and heterotrophic agar degrading bacterium. Here, we present the complete genome sequence of strain DA14, which comprises 3.96 Mb sequences with 53.39% GC content. In total, 3391 CDSs, 6 rRNA genes and 44 tRNA genes were obtained. Genomic analysis of strain DA14 revealed that 218 CAZymes classes were identified and they were organized in 371 CAZymes in PULs involved in polysaccharides degradation, transport and regulation. Further, we performed the genome comparison among Gilvimarinus strains and analysis the diversity of CAZymes and PULs. Meanwhile, ability of agar and alginate degradation in strain DA14 were analyzed. This study represents a thorough genomic characterization of CAZymes repertoire of Gilvimarinus, provides insight into diversity of polysaccharide degrading enzymes existing in Gilvimarinus sp. DA14 and their biotechnological applications.


Assuntos
Gammaproteobacteria , Genoma Bacteriano , Ágar/metabolismo , China , Gammaproteobacteria/genética , Análise de Sequência de DNA
9.
Mar Genomics ; 62: 100899, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35246304

RESUMO

Crassaminicella sp. 143-21, a putative new species isolated from deep-sea hydrothermal vent chimney on the Central Indian Ridge (CIR), is an anaerobic, thermophilic and rod-shaped bacterium belonging to the family Clostridiaceae. In this study, we present the complete genome sequence of strain 143-21, comprising 2,756,133 bp with a G + C content of 31.1%. In total, 2427 protein coding genes, 121 tRNA genes and 33 rRNA genes were obtained. Genomic analysis of strain 143-21 revealed that numerous genes related to organic matter transport and catabolism, including peptide transport, amino acid transport, saccharide transport, ethanolamine transport and corresponding metabolic pathways. Further, the genome contains a large proportion of genes involved in translation, ribosomal structure, and signal transduction. These genes might facilitate microbial survival in deep-sea hydrothermal vent environment. The genome of strain 143-21 will be helpful for further understanding its adaptive strategies in the deep-sea hydrothermal vent environment.


Assuntos
Fontes Hidrotermais , Composição de Bases , Clostridiaceae/genética , Genoma Bacteriano , Fontes Hidrotermais/microbiologia , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA
10.
Mar Life Sci Technol ; 4(2): 255-267, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-37073225

RESUMO

Deep-sea hydrothermal vents are known as chemosynthetic ecosystems. However, high temperature vents emit light that hypothetically can drive photosynthesis in this habitat. Metagenomic studies have sporadically reported the occurrence of phototrophic populations such as cyanobacteria in hydrothermal vents. To determine how geographically and taxonomically widespread phototrophs are in deep-sea hydrothermal vents, we collected samples from three niches in a hydrothermal vent on the Southwest Indian Ridge and carried out an integrated metagenomic analysis. We determined the typical community structures of microorganisms found in active venting fields and identified populations of known potential chlorophototrophs and retinalophototrophs. Complete chlorophyll biosynthetic pathways were identified in all samples. By contrast, proteorhodopsins were only found in active beehive smoker diffusers. Taxonomic groups possessing potential phototrophy dependent on semiconductors present in hydrothermal vents were also found in these samples. This systematic comparative metagenomic study reveals the widespread distribution of phototrophic bacteria in hydrothermal vent fields. Our results support the hypothesis that the ocean is a seed bank of diverse microorganisms. Geothermal vent light may provide energy and confer a competitive advantage on phototrophs to proliferate in hydrothermal vent ecosystems. Supplementary Information: The online version contains supplementary material available at 10.1007/s42995-021-00121-y.

11.
Int J Syst Evol Microbiol ; 71(11)2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34825884

RESUMO

A novel moderately thermophilic, anaerobic, heterotrophic bacterium (strain SY095T) was isolated from a hydrothermal vent chimney located on the Southwest Indian Ridge at a depth of 2730 m. Cells were Gram-stain-positive, motile, straight to slightly curved rods forming terminal endospores. SY095T was grown at 45-60 °C (optimum 50-55 °C), pH 6.0-7.5 (optimum 7.0), and in a salinity of 1-4.5 % (w/v) NaCl (optimum 2.5 %). Substrates utilized by SY095T included fructose, glucose, maltose, N-acetyl glucosamine and tryptone. Casamino acid and amino acids (glutamate, glutamine, lysine, methionine, serine and histidine) were also utilized. The main end products from glucose fermentation were acetate, H2 and CO2. Elemental sulphur, sulphate, thiosulphate, sulphite, fumarate, nitrate, nitrite and Fe(III) were not used as terminal electron acceptors. The predominant cellular fatty acids were C14 : 0 (60.5%) and C16 : 0 (7.6 %). The main polar lipids consisted of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, five unidentified phospholipids and two unidentified aminophospholipids. No respiratory quinones were detected. The chromosomal DNA G+C content was 30.8 mol%. The results of phylogenetic analysis of the 16S rRNA gene sequences indicated that SY095T was closely related to Crassaminicella profunda Ra1766HT (95.8 % 16S rRNA gene sequence identity). SY095T exhibited 78.1 % average nucleotide identity (ANI) to C. profunda Ra1766HT. The in silico DNA-DNA hybridization (DDH) value indicated that SY095T shared 22.7 % DNA relatedness with C. profunda Ra1766HT. On the basis of its phenotypic, genotypic and phylogenetic characteristics, SY095T is suggested to represent a novel species of the genus Crassaminicella, for which the name Crassaminicella thermophila sp. nov. is proposed. The type strain is SY095T (=JCM 34213=MCCC 1K04191). An emended description of the genus Crassaminicella is also proposed.


Assuntos
Clostridiaceae/classificação , Fontes Hidrotermais , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , Clostridiaceae/isolamento & purificação , DNA Bacteriano/genética , Ácidos Graxos/química , Fontes Hidrotermais/microbiologia , Oceano Índico , Hibridização de Ácido Nucleico , Fosfolipídeos/química , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA
12.
Artigo em Inglês | MEDLINE | ID: mdl-34343062

RESUMO

A hyperthermophilic, strictly anaerobic archaeon, designated strain SY113T, was isolated from a deep-sea hydrothermal vent chimney on the Southwest Indian Ridge at a water depth of 2770 m. Enrichment and isolation of strain SY113T were performed at 85 °C at 0.1 MPa. Cells of strain SY113T were irregular motile cocci with peritrichous flagella and generally 0.8-2.4 µm in diameter. Growth was observed at temperatures between 50 and 90 °C (optimum at 85 °C) and under hydrostatic pressures of 0.1-60 MPa (optimum, 27 MPa). Cells of SY113T grew at pH 4.0-9.0 (optimum, pH 5.5) and a NaCl concentration of 0.5-5.5 % (w/v; optimum concentration, 3.0 % NaCl). Strain SY113T was an anaerobic chemoorganoheterotroph and grew on complex proteinaceous substrates such as yeast extract and tryptone, as well as on maltose and starch. Elemental sulphur stimulated growth, but not obligatory for its growth. The G+C content of the genomic DNA was 55.0 mol%. Phylogenetic analysis of the 16S rRNA sequence of strain SY113T showed that the novel isolate belonged to the genus Thermococcus. On the basis of physiological characteristics, average nucleotide identity values and in silico DNA-DNA hybridization results, we propose a novel species, named Thermococcus aciditolerans sp. nov. The type strain is SY113T (=MCCC 1K04190T=JCM 39083T).


Assuntos
Fontes Hidrotermais , Filogenia , Água do Mar/microbiologia , Thermococcus , Composição de Bases , DNA Arqueal/genética , Fontes Hidrotermais/microbiologia , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , Thermococcus/classificação , Thermococcus/isolamento & purificação
13.
Microb Genom ; 7(7)2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34319226

RESUMO

Hadal trenches are the deepest but underexplored ecosystems on the Earth. Inhabiting the trench bottom is a group of micro-organisms termed obligate piezophiles that grow exclusively under high hydrostatic pressures (HHP). To reveal the genetic and physiological characteristics of their peculiar lifestyles and microbial adaptation to extreme high pressures, we sequenced the complete genome of the obligately piezophilic bacterium Moritella yayanosii DB21MT-5 isolated from the deepest oceanic sediment at the Challenger Deep, Mariana Trench. Through comparative analysis against pressure sensitive and deep-sea piezophilic Moritella strains, we identified over a hundred genes that present exclusively in hadal strain DB21MT-5. The hadal strain encodes fewer signal transduction proteins and secreted polysaccharases, but has more abundant metal ion transporters and the potential to utilize plant-derived saccharides. Instead of producing osmolyte betaine from choline as other Moritella strains, strain DB21MT-5 ferments on choline within a dedicated bacterial microcompartment organelle. Furthermore, the defence systems possessed by DB21MT-5 are distinct from other Moritella strains but resemble those in obligate piezophiles obtained from the same geographical setting. Collectively, the intensive comparative genomic analysis of an obligately piezophilic strain Moritella yayanosii DB21MT-5 demonstrates a depth-dependent distribution of energy metabolic pathways, compartmentalization of important metabolism and use of distinct defence systems, which likely contribute to microbial adaptation to the bottom of hadal trench.


Assuntos
Aclimatação/genética , Metabolismo Energético/genética , Genoma Bacteriano/genética , Moritella/genética , Colina/metabolismo , Ecossistema , Fermentação/genética , Fermentação/fisiologia , Pressão Hidrostática , Moritella/fisiologia , Oceanos e Mares , Microbiologia da Água , Sequenciamento Completo do Genoma
14.
Ultrasound Med Biol ; 47(4): 910-918, 2021 04.
Artigo em Inglês | MEDLINE | ID: mdl-33483161

RESUMO

The purpose of this study was to evaluate the role of 2-D speckle tracking imaging in assessing left ventricular diastolic function in patients with connective tissue disease (CTD). A total of 98 CTD patients and 32 healthy controls were prospectively recruited. Early (E) and late (A) diastolic velocities of the transmitral flow were measured by pulsed Doppler echocardiography. Peak early diastolic myocardial velocity (E') was calculated on tissue Doppler echocardiography. The longitudinal strain rate (SR) was calculated as the average of three apical views, while circumferential and radial SRs were measured in three short-axis views. Pulmonary arterial hypertension (PAH) was defined as systolic pulmonary arterial pressure (sPAP) >36 mm Hg. Compared with the control group, CTD patients exhibited significant impairment of left ventricular diastolic function, manifested as lower global SR during early diastole (SRe) in the longitudinal deformation and higher E/SRe in both longitudinal and radial deformation. CTD-PAH patients had significantly lower SRe and higher E/SRe values in both the longitudinal and radial deformation compared with the patients with CTD without PAH. Pearson's correlation analysis revealed that sPAP levels correlated positively with E/E', longitudinal E/SRe, circumferential E/SRe and radial SRe, and it correlated negatively with septal E' and radial E/SRe. Receiver operating characteristic curve analysis suggested that E/E', longitudinal E/SRe and radial SRe could be used to predict PAH. The present study indicates that 2-D speckle tracking imaging is a useful method for evaluation of left ventricular diastolic function, and these derived parameters can serve as good predictors of PAH, but it may not be superior to the commonly used E/E' in CTD patients.


Assuntos
Doenças do Tecido Conjuntivo/fisiopatologia , Ecocardiografia/métodos , Hipertensão Arterial Pulmonar/fisiopatologia , Disfunção Ventricular Esquerda/diagnóstico por imagem , Disfunção Ventricular Esquerda/fisiopatologia , Adulto , Velocidade do Fluxo Sanguíneo , Estudos de Casos e Controles , Doenças do Tecido Conjuntivo/complicações , Diástole , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Variações Dependentes do Observador , Estudos Prospectivos , Hipertensão Arterial Pulmonar/etiologia , Curva ROC , Reprodutibilidade dos Testes , Disfunção Ventricular Esquerda/etiologia
15.
Mar Genomics ; 52: 100733, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32571576

RESUMO

Crassaminicella sp. strain SY095 is an anaerobic mesophilic marine bacterium that was recently isolated from a deep-sea hydrothermal vent on the Southwest Indian Ridge. Here, we present the complete genome sequence of strain SY095. The genome consists of a chromosome of 3,046,753 bp (G + C content of 30.81%) and a plasmid of 36,627 bp (G + C content of 31.29%), encodes 2966 protein, 135 tRNA genes, and 34 rRNA genes. Numerous genes are related to peptide transport, amino acid metabolism, motility, and sporulation. This agrees with the observation that strain SY095 is a spore-forming, motile, and chemoheterotrophic bacterium. Further, the genome harbors multiple prophages that carry all the genes necessary for viral particle synthesis. Some prophages carry additional genes that may be involved in the regulation of sporulation. This is the first reported genome of a bacterium from the genus Crassaminicella, providing insights into the microbial adaptation strategies to the deep-sea hydrothermal vent environment.


Assuntos
Clostridiaceae/genética , Genoma Bacteriano , Fontes Hidrotermais/microbiologia , Anaerobiose , Clostridiaceae/metabolismo , Oceano Índico , Sequenciamento Completo do Genoma
16.
Front Microbiol ; 9: 3173, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30622525

RESUMO

Shewanella species are widely distributed in marine environments, from the shallow coasts to the deepest sea bottom. Most Shewanella species possess two isoforms of periplasmic nitrate reductases (NAP-α and NAP-ß) and are able to generate energy through nitrate reduction. However, the contributions of the two NAP systems to bacterial deep-sea adaptation remain unclear. In this study, we found that the deep-sea denitrifier Shewanella piezotolerans WP3 was capable of performing nitrate respiration under high hydrostatic pressure (HHP) conditions. In the wild-type strain, NAP-ß played a dominant role and was induced by both the substrate and an elevated pressure, whereas NAP-α was constitutively expressed at a relatively lower level. Genetic studies showed that each NAP system alone was sufficient to fully sustain nitrate-dependent growth and that both NAP systems exhibited substrate and pressure inducible expression patterns when the other set was absent. Biochemical assays further demonstrated that NAP-α had a higher tolerance to elevated pressure. Collectively, we report for the first time the distinct properties and contributions of the two NAP systems to nitrate reduction under different pressure conditions. The results will shed light on the mechanisms of bacterial HHP adaptation and nitrogen cycling in the deep-sea environment.

17.
Front Microbiol ; 8: 2646, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29375513

RESUMO

High hydrostatic pressure (HHP) exerts severe effects on cellular processes including impaired cell division, abolished motility and affected enzymatic activities. Transcriptomic and proteomic analyses showed that bacteria switch the expression of genes involved in multiple energy metabolism pathways to cope with HHP. We sought evidence of a changing bacterial metabolism by supplying appropriate substrates that might have beneficial effects on the bacterial lifestyle at elevated pressure. We isolated a piezosensitive marine bacterium Vibrio fluvialis strain QY27 from the South China Sea. When trimethylamine N-oxide (TMAO) was used as an electron acceptor for energy metabolism, QY27 exhibited a piezophilic-like phenotype with an optimal growth at 30 MPa. Raman spectrometry and biochemistry analyses revealed that both the efficiency of the TMAO metabolism and the activity of the TMAO reductase increased under high pressure conditions. Among the two genes coding for TMAO reductase catalytic subunits, the expression level and enzymatic activity of TorA was up-regulated by elevated pressure. Furthermore, a genetic interference assay with the CRISPR-dCas9 system demonstrated that TorA is essential for underpinning the improved pressure tolerance of QY27. We extended the study to Vibrio fluvialis type strain ATCC33809 and observed the same phenotype of TMAO-metabolism improved the pressure tolerance. These results provide compelling evidence for the determinant role of metabolism in the adaption of bacteria to the deep-sea ecosystems with HHP.

18.
Diagn Pathol ; 11(1): 136, 2016 Nov 24.
Artigo em Inglês | MEDLINE | ID: mdl-27881141

RESUMO

BACKGROUND: The origin and heterogeneity of hepatic progenitor cells (HPCs) remain unclear. This study aimed to investigate the involvement of epithelial-mesenchymal transition (EMT) in the histogenesis of HPCs. METHODS: Surgical liver specimens from patients with HBV-related hepatitis and cirrhosis were investigated with double immunofluorescence labeling to detect antigens associated with HPCs and EMT. Ductular reactions were subjected to quantitative reverse transcription PCR following isolation by laser capture microdissection. Electron microscopic examination was performed to find an ultrastructural evidence of EMT. RESULTS: The number of EpCAM-positive HPCs was proportional to the disease severity. The S100A4 expression of HPCs was firstly observed in mild hepatitis and increased significantly in moderate hepatitis, but decreased in severe hepatitis and cirrhosis. The levels of MMP-2, Twist, and Snail increased in direct proportion to the number of HPCs. Some hepatocytes adjacent to portal tracts in cirrhosis showed positivity for MMP-2. Although CK7 and E-cadherin levels decreased in mild and moderate hepatitis, HPCs re-expressed both of them in severe hepatitis and cirrhosis. However, HPCs expressed neither vimentin nor αSMA. The relative mRNA expression levels of EpCAM and EMT-associated markers supported immunohistochemical results. Electron microscopic examination demonstrated the existence of intercellular junctions among HPCs, cholangiocytes, and intermediate hepatocyte-like cells. CONCLUSION: We provided preliminary evidence for the involvement of EMT in the histogenesis of HPCs from cholangiocytes in HBV-related liver diseases. HPCs may re-transdifferentiate into hepatocytes, and the differentiation direction depends, at least in part, on interactions between HPCs and the surrounding microenvironment, especially the non-resolving inflammation caused by HBV infection.


Assuntos
Transição Epitelial-Mesenquimal , Hepatite B/patologia , Hepatócitos/patologia , Células-Tronco/citologia , Adulto , Biomarcadores/análise , Feminino , Imunofluorescência , Humanos , Microdissecção e Captura a Laser , Cirrose Hepática/patologia , Masculino , Microscopia Eletrônica de Transmissão , Pessoa de Meia-Idade
19.
Diagn Pathol ; 11: 36, 2016 Apr 11.
Artigo em Inglês | MEDLINE | ID: mdl-27066782

RESUMO

BACKGROUND: The clear cell/signet-ring cell variant of cutaneous squamous cell carcinoma (cSCC) is extremely rare. Its carcinogenesis has consistently been linked to ultraviolet radiation and HPV in the literature. However, there is little definite information about the contribution of diabetes mellitus (DM) to cSCC. CASE PRESENTATION: A 78-year-old Chinese woman with type 2 DM presented with a mushroom-like lump in her right thigh. Histological findings revealed that the lesion was mainly composed of clear cells and signet-ring cells. The septa of vacuoles in cytoplasm displayed positivity for periodic acid schiff (PAS) and cytokeratins such as AE1/AE3, CK5/6, CK14, and CK19. Malignant cells did not express CK7, CK8, CK18, CK20, p16, p53, or c-erbB-2, and the Ki-67 index was less than 5 %. We further explored the etiology of clear cell/signet-ring cell cSCC using human papillomavirus (HPV) type-specific PCR and genotyping and confirmed that the patient was not infected with HPV. Nucleus positivity for p63 indicated the involvement of the p53 family in the lesion. Meanwhile, the expression of fibroblast growth factor receptor-2 (FGFR2), a downstream effector of p63, was upregulated in tumor cells. CONCLUSIONS: This study provides the first report on the clear cell/signet-ring cell variant of cSCC found in the right thigh of a patient with type 2 DM. Metabolic imbalance in addition to conventional pathogens such as UV and HPV may contribute to the development of the lesion via p63/FGFR2 axis.


Assuntos
Biomarcadores Tumorais/análise , Carcinoma de Células em Anel de Sinete/etiologia , Carcinoma de Células Escamosas/etiologia , Diabetes Mellitus Tipo 2/complicações , Imuno-Histoquímica , Neoplasias Cutâneas/complicações , Idoso , Biópsia , Carcinoma de Células em Anel de Sinete/química , Carcinoma de Células em Anel de Sinete/patologia , Carcinoma de Células em Anel de Sinete/cirurgia , Carcinoma de Células Escamosas/química , Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Humanos , Valor Preditivo dos Testes , Fatores de Risco , Neoplasias Cutâneas/química , Neoplasias Cutâneas/patologia , Neoplasias Cutâneas/cirurgia , Coxa da Perna
20.
Biomed Rep ; 2(3): 331-334, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24748969

RESUMO

Metastasis, a cascade of events beginning with epithelial-to-mesenchymal transition (EMT), is the main cause of cancer-related mortality. EMT endows circulating cancer cells (CTCs) with invasive and anti-apoptotic properties. These transitioning cells leave the primary tumor site and travel through the circulation to populate remote organs, even prior to the onset of clinical symptoms. During this journey, CTCs activate platelets, which in turn secrete α-granules. These α-granules contain high levels of transforming growth factor-ß (TGF-ß) and platelet-derived growth factor (PDGF), both considered to be powerful activators of EMT. Recently, regular aspirin use was associated with a reduced risk of cancer metastasis. However, the molecular mechanism underlying the chemotherapeutic effects of aspirin on metastasis has not been fully elucidated. As platelets lack a nucleus, regular aspirin use may exert long-lasting effects on irreversible inhibition of cyclooxygenase (COX)-1 and, subsequently, the secretion of α-granules, which contributes to the maintenance of the EMT state of CTCs. Thus, we hypothesized that the inhibition of platelet-induced EMT of CTCs through the COX-1 signaling pathway may contribute to the intriguing antimetastatic potential of aspirin.

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