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1.
Nucleic Acids Res ; 51(22): e112, 2023 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-37941145

RESUMEN

We presented an experimental method called FLOUR-seq, which combines BD Rhapsody and nanopore sequencing to detect the RNA lifecycle (including nascent, mature, and degrading RNAs) in cells. Additionally, we updated our HIT-scISOseq V2 to discover a more accurate RNA lifecycle using 10x Chromium and Pacbio sequencing. Most importantly, to explore how single-cell full-length RNA sequencing technologies could help improve the RNA velocity approach, we introduced a new algorithm called 'Region Velocity' to more accurately configure cellular RNA velocity. We applied this algorithm to study spermiogenesis and compared the performance of FLOUR-seq with Pacbio-based HIT-scISOseq V2. Our findings demonstrated that 'Region Velocity' is more suitable for analyzing single-cell full-length RNA data than traditional RNA velocity approaches. These novel methods could be useful for researchers looking to discover full-length RNAs in single cells and comprehensively monitor RNA lifecycle in cells.


Asunto(s)
Secuenciación de Nanoporos , Análisis de Secuencia de ARN , Análisis de la Célula Individual , Algoritmos , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Secuenciación de Nanoporos/métodos , Análisis de Secuencia de ARN/métodos
2.
Org Biomol Chem ; 22(11): 2182-2186, 2024 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-38390690

RESUMEN

Three novel phragmalin-type limonoids, swieteliacates S-U (1-3), were isolated from Swietenia macrophylla leaves, alongside four previously identified limonoids (4-7). The structures, encompassing absolute configurations, were delineated through 1D and 2D NMR analyses, high-resolution mass spectrometry (HR-MS), and NMR and ECD calculations. Swieteliacate S (1) is a distinctive cryptate comprising a tricyclo[4.2.110,30.11,4]decane fragment and an additional five-membered oxygen ring. Compounds 3 and 5 exhibited inhibition rates of 26.08 ± 2.26% and 15.42 ± 3.66%, respectively, on triglyceride (TG) production in Hep G2 cells at 40 µM.


Asunto(s)
Limoninas , Meliaceae , Limoninas/química , Limoninas/farmacología , Estructura Molecular , Espectroscopía de Resonancia Magnética , Meliaceae/química
3.
BMC Med Educ ; 24(1): 709, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38951842

RESUMEN

OBJECTIVE: In this study, we added laboratory animal ethics education into both didactic sessions and practical sessions the general surgery laboratory course, with the didactic sessions focus on teaching the fundamental principles of laboratory animal ethics, while the practical sessions emphasize the application of these principles in laboratory classes and have assessed the changes in medical students' perception of laboratory animal ethics following medical students exposure to such education. METHODS: One hundred and eighty-nine third-year medical students from Wuhan University's Second Clinical College completed a laboratory animal ethics awareness questionnaire and a laboratory animal ethics written examination before and after laboratory animal ethics education. RESULTS: After receiving laboratory animal ethics education, the percentage of students who supported euthanasia for the execution of animals and humane treatment of laboratory animals were 95.2% and 98.8%, respectively, which did not differ from the 94.9% and 96.4% observed before the education. Moreover, there was a notable increase in the proportion of students who knew about regulations related to laboratory animals (from 39.9% to 57.1%), welfare issues (from 31.9% to 50.0%), and the 3R principle (from 30.4% to 58.9%) post-education, all statistically significant at P < 0.05. Test scores also showed improvement, with students scoring (93.02 ± 11.65) after education compared to (67.83 ± 8.08) before, a statistically significant difference. CONCLUSIONS: This research helps to provide information for the good practices of laboratory animal ethics education. After receiving laboratory animal ethics education, students are better able to treat laboratory animals in a correct animal ethical manner. Laboratory animal ethics education helps improve students' knowledge of laboratory animal ethics. Students' perception towards how the laboratory animal ethics course should be delivered may vary. Still, new courses or better organized courses on laboratory animal ethics education are required in order to provide students an in-depth understanding.


Asunto(s)
Estudiantes de Medicina , Humanos , Estudiantes de Medicina/psicología , Animales , Educación de Pregrado en Medicina , Masculino , Femenino , Curriculum , Animales de Laboratorio , Encuestas y Cuestionarios , Ciencia de los Animales de Laboratorio/educación , Ciencia de los Animales de Laboratorio/ética , Bienestar del Animal/ética , Experimentación Animal/ética , China , Evaluación Educacional , Adulto Joven , Concienciación
4.
Behav Sci Law ; 2024 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-38840489

RESUMEN

Cyberbullying is considered a major threat to adolescent anxiety. In this study, we aim to explore the simultaneous effects of cyberbullying victimization and perpetration on youth anxiety. Building on the childhood adversity model and the vulnerability-stress model, we test the model wherein cyberbullying exposure is linked with cyberostracism, which in turn is expected to be associated with an increase in anxiety. We collected data from 1115 Chinese youth aged 11-19 years based on the stratified random sampling method. Structure equation modelling was conducted in Amos 26.0 to examine the proposed theoretical model. The findings suggested that compared with cyberbullying perpetration, the experience of cyberbullying victimization led to a significantly higher risk of youth anxiety. Multiple mediation analyses revealed that the three dimensions of cyberostracism, namely cyber direct excluded, cyber indirect excluded and cyber ignored, mediated the association of cyberbullying victimization and perpetration with youth anxiety. These results indicate that cyberostracism could be a risk factor for youth anxiety, thus providing new direction regarding intervention programs to reduce anxiety symptoms in adolescents.

5.
Microb Ecol ; 86(2): 1200-1212, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-36068360

RESUMEN

Intestinal microbes are essential participants in host vital activities. The composition of the microbiota is closely related to the environmental factors. Predator presence may impact on intestinal microbiota of prey. In the present study, stone crab Charybdis japonica was used as potential predator, an external stress on mussel Mytilus coruscus, to investigate the intestinal microbiota alteration in M. coruscus. We set up two forms of predator presence including free crab and trapped crab, with a blank treatment without crab. The composition of intestinal microbiota in mussels among different treatments showed significant differences by 16S rRNA techniques. The biodiversity increased with trapped crab presence, but decreased with free crab presence. Neisseria, the most abundant genus, fell with the presence of crabs. Besides, the Arcobacter, a kind of pathogenic bacteria, increased with free crab presence. Regarding PICRUTs analysis, Environmental Information Processing, Genetic Information Processing and Metabolism showed differences in crab presence treatments compared with the blank, with a bit higher in the presence of free crab than trapped crab. In conclusion, trapped crab effects activated the metabolism and immunity of the intestinal flora, but free crabs made mussels more susceptible to disease and mortality, corresponding to the decreased biodiversity and the increased Arcobacter in their intestine.


Asunto(s)
Braquiuros , Microbioma Gastrointestinal , Mytilus , Animales , Humanos , ARN Ribosómico 16S/genética , Biodiversidad
6.
Acta Neurochir (Wien) ; 165(10): 3077-3087, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37488398

RESUMEN

BACKGROUND: Visual instruments are essential to ensure high-quality surgical outcomes for minimally invasive procedures and have gradually become the focus of research. Recently, a novel visual auxiliary instrument, a 3-dimensional exoscope (EX), has been applied for spinal surgery. However, its advantages over other auxiliary means (OAMs) in anterior cervical surgery need to be assessed. OBJECTIVE: To compare and evaluate the clinical outcomes of EX and OAMs in anterior cervical spine surgery using a meta-analysis and to provide the latest clinical evidence. METHODS: PubMed, Embase, Cochrane Library, Web of Science, CNKI, and Wanfang Database were systematically reviewed for relevant literature published prior to January 21, 2023. Two researchers independently screened the literature, extracted data, and assessed bias risk in the included literature. Review Manager software (version 5.4; the Cochrane Collaboration) was used to conduct the meta-analysis. RESULTS: five studies, one prospective and four retrospective cohort studies, with a total of 349 patients (154 in the EX group and 195 in the OAMs group) were included. A meta-analysis showed that compared to OAMs, EX-assisted anterior cervical spine surgery resulted in less intraoperative hemorrhage [WMD = -8.96, 95% CI (-14.21, -3.71), P = 0.0008]. Nevertheless, no significant differences in VAS scores, JOA scores, operation time, hospitalization time, and complication rate were observed between the two groups (P > 0.05). CONCLUSION: EX and OAMs are equally safe and effective for anterior cervical spine surgery; however, compared to OAMs, EX results in less intraoperative hemorrhage.


Asunto(s)
Vértebras Cervicales , Fusión Vertebral , Humanos , Vértebras Cervicales/diagnóstico por imagen , Vértebras Cervicales/cirugía , Estudios Retrospectivos , Estudios Prospectivos , Fusión Vertebral/métodos , Pérdida de Sangre Quirúrgica , Resultado del Tratamiento
7.
Sensors (Basel) ; 23(3)2023 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-36772577

RESUMEN

To achieve automatic disc cutter replacement of shield machines, measuring the accurate pose of the disc cutter holder by machine vision is crucial. However, under polluted and restricted illumination conditions, achieving pose estimation by vision is a great challenge. This paper proposes a line-features-based pose estimation method for the disc cutter holder of the shield machine by using a monocular camera. For the blurring effect of rounded corners on the image edge, a rounded edge model is established to obtain edge points that better match the 3D model of the workpiece. To obtain the edge search box corresponding to each edge, a contour separation method based on an adaptive threshold region growing method is proposed. By preprocesses on the edge points of each edge, the efficiency and the accuracy of RANSAC linear fitting are improved. The experimental result shows that the proposed pose estimation method is highly reliable and can meet the measurement accuracy requirements in practical engineering applications.

8.
Sensors (Basel) ; 22(2)2022 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-35062428

RESUMEN

The visual measurement system plays a vital role in the disc cutter changing robot of the shield machine, and its accuracy directly determines the success rate of the disc cutter grasping. However, the actual industrial environment with strong noise brings a great challenge to the pose measurement methods. The existing methods are difficult to meet the required accuracy of pose measurement based on machine vision under the disc cutter changing conditions. To solve this problem, we propose a monocular visual pose measurement method consisting of the high precision optimal solution to the PnP problem (OPnP) method and the highly robust distance matching (DM) method. First, the OPnP method is used to calculate the rough pose of the shield machine's cutter holder, and then the DM method is used to measure its pose accurately. Simulation results show that the proposed monocular measurement method has better accuracy and robustness than the several mainstream PnP methods. The experimental results also show that the maximum error of the proposed method is 0.28° in the direction of rotation and 0.32 mm in the direction of translation, which can meet the measurement accuracy requirement of the vision system of the disc cutter changing robot in practical engineering application.

9.
J Hepatol ; 75(5): 1058-1071, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34171437

RESUMEN

BACKGROUND & AIMS: Current antiviral therapies control but rarely eliminate HBV, leaving chronic HBV carriers at risk of developing hepatocellular carcinoma (HCC). Lacking or dysfunctional virus-specific adaptive immunity prevents control of HBV and allows the virus to persist. Restoring antiviral T-cell immunity could lead to HBV elimination and cure of chronically infected patients. METHODS: We constructed bispecific T-cell engager antibodies that are designed to induce antiviral immunity through simultaneous binding of HBV envelope proteins (HBVenv) on infected hepatocytes and CD3 or CD28 on T cells. T-cell engager antibodies were employed in co-cultures with healthy donor lymphocytes and HBV-infected target cells. Activation of the T-cell response was determined by detection of pro-inflammatory cytokines, effector function (by cytotoxicity) and antiviral effects. To study in vivo efficacy, immune-deficient mice were transplanted with HBVenv-positive and -negative hepatoma cells. RESULTS: The 2 T-cell engager antibodies synergistically activated T cells to become polyfunctional effectors that in turn elicited potent antiviral effects by killing infected cells and in addition controlled HBV via non-cytolytic, cytokine-mediated antiviral mechanisms. In vivo in mice, the antibodies attracted T cells specifically to the tumors expressing HBVenv resulting in T-cell activation, tumor infiltration and reduction of tumor burden. CONCLUSION: This study demonstrates that the administration of HBVenv-targeting T-cell engager antibodies facilitates a robust T-cell redirection towards HBV-positive target cells and provides a feasible and promising approach for the treatment of chronic viral hepatitis and HBV-associated HCC. LAY SUMMARY: T-cell engager antibodies are an interesting, novel therapeutic tool to restore immunity in patients with chronic hepatitis B. As bispecific antibodies, they bind envelope proteins on the surface of the hepatitis B virus (HBV) and CD3 or CD28 on T cells. This way, they induce a potent antiviral and cytotoxic T-cell response that leads to the elimination of HBV-positive cells. These bispecific T-cell engager antibodies are exciting therapeutic candidates for chronic hepatitis B and HBV-associated hepatocellular carcinoma.


Asunto(s)
Antígenos de la Hepatitis B/sangre , Hepatitis B/sangre , Linfocitos T/inmunología , Animales , Modelos Animales de Enfermedad , Citometría de Flujo/métodos , Citometría de Flujo/estadística & datos numéricos , Hepatitis B/epidemiología , Antígenos de la Hepatitis B/análisis , Antígenos de la Hepatitis B/metabolismo , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/patogenicidad , Ratones , Estadísticas no Paramétricas , Linfocitos T/fisiología
10.
Small ; 16(36): e2002019, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32761797

RESUMEN

Titanium dioxide nanoparticles (nano-TiO2 ) are widely used in consumer products, raising environmental and health concerns. An overview of the toxic effects of nano-TiO2 on human and environmental health is provided. A meta-analysis is conducted to analyze the toxicity of nano-TiO2 to the liver, circulatory system, and DNA in humans. To assess the environmental impacts of nano-TiO2 , aquatic environments that receive high nano-TiO2 inputs are focused on, and the toxicity of nano-TiO2 to aquatic organisms is discussed with regard to the present and predicted environmental concentrations. Genotoxicity, damage to membranes, inflammation and oxidative stress emerge as the main mechanisms of nano-TiO2 toxicity. Furthermore, nano-TiO2 can bind with free radicals and signal molecules, and interfere with the biochemical reactions on plasmalemma. At the higher organizational level, nano-TiO2 toxicity is manifested as the negative effects on fitness-related organismal traits including feeding, reproduction and immunity in aquatic organisms. Bibliometric analysis reveals two major research hot spots including the molecular mechanisms of toxicity of nano-TiO2 and the combined effects of nano-TiO2 and other environmental factors such as light and pH. The possible measures to reduce the harmful effects of nano-TiO2 on humans and non-target organisms has emerged as an underexplored topic requiring further investigation.


Asunto(s)
Organismos Acuáticos , Nanopartículas , Titanio , Toxicología , Animales , Organismos Acuáticos/efectos de los fármacos , Daño del ADN , Humanos , Nanopartículas/toxicidad , Estrés Oxidativo , Titanio/toxicidad , Toxicología/normas , Toxicología/tendencias
11.
Int J Syst Evol Microbiol ; 70(4): 2560-2568, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32129736

RESUMEN

A piezotolerant, H2O2-tolerant, heavy-metal-tolerant, slightly halophilic bacterium (strain NBT06E8T) was isolated from a deep-sea sediment sample collected from the New Britain Trench at depth of 8900 m. The strain was aerobic, motile, Gram-stain-negative, rod-shaped, oxidase-positive and catalase-positive. Growth of the strain was observed at 4-45 °C (optimum, 30 °C), at pH 5-11 (optimum, pH 8-9) and in 0.5-21 % (w/v) NaCl (optimum, 3-7 %). The optimum pressure for growth was 0.1-30 MPa with tolerance up to 60 MPa. Under optimum growth conditions, the strain could tolerate 15 mM H2O2. Resuls of 16S rRNA gene sequence analysis showed that strain NBT06E8T is closely related to Halomonas aquamarina DSM 30161T (99.5%), Halomonas meridiana DSM 5425T (99.43%) and Halomonas axialensis Althf1T (99.35%). The digital DNA-DNA hybridization values between strain NBT06E8T and the three related type strains, H. aquamarina, H. meridiana and H. axialensis, were 30.5±2.4 %, 30.7±2.5% and 31.5±2.5 %, respectively. The average nucleotide identity values between strain NBT06E8T and the three related type strains were 86.26, 86.26 and 83.63 %, respectively. The major fatty acids were summed feature 8 (C18 : 1 ω7c and/or C18 : 1 ω6c) and C16 : 0. The predominant respiratory quinone detected was ubiquinone-9 (Q-9). Based on its phenotypic and phylogenetic characteristics, we conclude that strain NBT06E8T represents a novel species of the genus Halomonas, for which the name Halomonas piezotolerans sp. nov. is proposed (type strain NBT06E8T= MCCC 1K04228T=KCTC 72680T).


Asunto(s)
Sedimentos Geológicos/microbiología , Halomonas/clasificación , Filogenia , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Halomonas/aislamiento & purificación , Hibridación de Ácido Nucleico , Océano Pacífico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Ubiquinona/química
12.
Int J Syst Evol Microbiol ; 70(7): 4315-4320, 2020 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-32579094

RESUMEN

A novel marine Gram-stain-negative, non-motile, aerobic and rod-shaped bacterium, designated as strain MT-229T, was isolated from the deep seawater in the Mariana Trench and characterized phylogenetically and phenotypically. Bacterial optimal growth occurred at 30 °C (ranging 10-40 °C), pH 6 (ranging 3-11) and with 11 % (w/v) NaCl (ranging 0-17 %). Strain MT-229T was a piezophile, growing optimally at 20 MPa (range 0.1-70 MPa). The nearest phylogenetic neighbours were Muricauda antarctica CGMCC 1.2174T and Muricauda taeanensis JCM 17757T with 16S rRNA gene similarity of 98.7 %. The sole respiratory quinone was menaquinone-6 (MK-6). The major polar lipids were phosphatidylethanolamine (PE), two unidentified aminolipids (AL) and ten unidentified lipids. The major fatty acids of strain MT-229T were iso-C15 : 0, iso-C17 : 0 3-OH and iso-C15 : 1 G. The G+C content of the genomic DNA was 45.6 mol%. The combined genotypic and phenotypic data indicated that strain MT-229T represents a novel species of the genus Muricauda, for which the name Muricauda hadalis sp. nov. is proposed, with the type strain MT-229T (=DSM 109894T=MCCC 1K04201T). In addition, the whole-genome-based comparisons revealed that the type strains of Muricauda antarctica and Muricauda teanensis belong to a single species. It is, therefore, proposed that M. antarctica be recognized as a heterotypic synonym of M. teanensis.


Asunto(s)
Flavobacteriaceae/clasificación , Filogenia , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Flavobacteriaceae/aislamiento & purificación , Océano Pacífico , Fosfatidiletanolaminas/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Vitamina K 2/análogos & derivados , Vitamina K 2/química
13.
J Digit Imaging ; 33(5): 1144-1154, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32705434

RESUMEN

The early stage lung cancer often appears as ground-glass nodules (GGNs). The diagnosis of GGN as preinvasive lesion (PIL) or invasive adenocarcinoma (IA) is very important for further treatment planning. This paper proposes an automatic GGNs' invasiveness classification algorithm for the adenocarcinoma. 1431 clinical cases and a total of 1624 GGNs (3-30 mm) were collected from Shanghai Cancer Center for the study. The data is in high-resolution computed tomography (HRCT) format. Firstly, the automatic GGN detector which is composed by a 3D U-Net and a 3D multi-receptive field (multi-RF) network detects the location of GGNs. Then, a deep 3D convolutional neural network (3D-CNN) called Attention-v1 is used to identify the GGNs' invasiveness. The attention mechanism was introduced to the 3D-CNN. This paper conducted a contract experiment to compare the performance of Attention-v1, ResNet, and random forest algorithm. ResNet is one of the most advanced convolutional neural network structures. The competition performance metrics (CPM) of automatic GGN detector reached 0.896. The accuracy, sensitivity, specificity, and area under curve (AUC) value of Attention-v1 structure are 85.2%, 83.7%, 86.3%, and 92.6%. The algorithm proposed in this paper outperforms ResNet and random forest in sensitivity, accuracy, and AUC value. The deep 3D-CNN's classification result is better than traditional machine learning method. Attention mechanism improves 3D-CNN's performance compared with the residual block. The automatic GGN detector with the addition of Attention-v1 can be used to construct the GGN invasiveness classification algorithm to help the patients and doctors in treatment.


Asunto(s)
Neoplasias Pulmonares , Tomografía Computarizada por Rayos X , China , Humanos , Pulmón , Neoplasias Pulmonares/diagnóstico por imagen , Invasividad Neoplásica
14.
J Med Syst ; 44(5): 96, 2020 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-32193703

RESUMEN

Optic disc (OD) and optic cup (OC) segmentation are important steps for automatic screening and diagnosing of optic nerve head abnormalities such as glaucoma. Many recent works formulated the OD and OC segmentation as a pixel classification task. However, it is hard for these methods to explicitly model the spatial relations between the labels in the output mask. Furthermore, the proportion of the background, OD and OC are unbalanced which also may result in a biased model as well as introduce more noise. To address these problems, we developed an approach that follows a coarse-to-fine segmentation process. We start with a U-Net to obtain a rough segmenting boundary and then crop the area around the boundary to form a boundary contour centered image. Second, inspired by sequence labeling tasks in natural language processing, we regard the OD and OC segmentation as a sequence labeling task and propose a novel fully convolutional network called SU-Net and combine it with the Viterbi algorithm to jointly decode the segmentation boundary. We also introduced a geometric parameter-based data augmentation method to generate more training samples in order to minimize the differences between training and test sets and reduce overfitting. Experimental results show that our method achieved state-of-the-art results on 2 datasets for both OD and OC segmentation and our method outperforms most of the ophthalmologists in terms of achieving agreement out of 6 ophthalmologists on the MESSIDOR dataset for both OD and OC segmentation. In terms of glaucoma screening, we achieved the best cup-to-disc ratio (CDR) error and area under the ROC curve (AUC) for glaucoma classification on the Drishti-GS dataset.


Asunto(s)
Glaucoma , Procesamiento de Imagen Asistido por Computador , Redes Neurales de la Computación , Disco Óptico/diagnóstico por imagen , Fondo de Ojo , Glaucoma/diagnóstico , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Procesamiento de Lenguaje Natural
15.
Zhongguo Yi Liao Qi Xie Za Zhi ; 44(6): 471-475, 2020 Dec 08.
Artículo en Zh | MEDLINE | ID: mdl-33314851

RESUMEN

A clinical information navigation system based on 3D human body model is designed. The system extracts the key information of diagnosis and treatment of patients by searching the historical medical records, and stores the focus information in a predefined structured patient instance. In addition, the rule mapping is established between the patient instance and the three-dimensional human body model, the focus information is visualized on the three-dimensional human body model, and the trend curve can be drawn according to the change of the focus, meanwhile, the key diagnosis and treatment information and the original report reference function are provided. The system can support the analysis, storage and visualization of various types of reports, improve the efficiency of doctors' retrieval of patient information, and reduce the treatment time.


Asunto(s)
Aplicaciones de la Informática Médica , Modelos Anatómicos , Diagnóstico por Computador , Humanos , Programas Informáticos
16.
Antonie Van Leeuwenhoek ; 112(10): 1545-1552, 2019 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-31114973

RESUMEN

A Gram-stain negative, non-motile and short rod shaped bacterium, designated strain DSL-12T, was isolated from seawater of the East China Sea and characterised phylogenetically and phenotypically. Optimal growth was found to occur at 28 °C (range 4-40 °C), pH 7 (range 6-12) and with 3% (w/v) NaCl (range 0-8%). Phylogenetic analysis based on the 16S rRNA gene sequence showed that strain DSL-12T is related to members of the genus Algoriphagus and shares high sequence similarities with Algoriphagus boritolerans DSM 17298T (97.6%) and Algoriphagus alkaliphilus DSM 22703T (97.6%). The 16S rRNA gene sequence identities between strain DSL-12T and other current members of the genus Algoriphagus were below 96.4%. The digital DNA-DNA hybridization values between strain DSL-12T and the type strains A. boritolerans DSM 17298T and A. alkaliphilus DSM 22703T were found to be 21.2 ± 2.4% and 20.2 ± 2.4%, respectively. The average nucleotide identity (ANI) values between strain DSL-12T and A. boritolerans DSM 17298T and A. alkaliphilus DSM 22703T were found to be 83.2% and 82.8%, respectively. The sole respiratory quinone was identified as MK-7. The major polar lipids were identified as phosphatidylethanolamine, diphosphatidylglycerol, one unidentified phospholipid and two unidentified lipids. The major fatty acids identified as were iso-C15:0, summed feature 8 (C18:1ω7c and/or C18:1ω6c), C16:0, summed feature 3 (C16:1ω7c and/or C16:1ω6c) and iso-C17:0. The G+C content of the genomic DNA was determined to be 43.3 mol%. The combined genotypic and phenotypic data indicate that strain DSL-12T represents a novel species of the genus Algoriphagus, for which the name Algoriphagus litoralis sp. nov. is proposed, with the type strain DSL-12T (= KCTC 62647T = MCCC 1K03536T).


Asunto(s)
Bacteroidetes/clasificación , Bacteroidetes/aislamiento & purificación , Agua Dulce/microbiología , Agua de Mar/microbiología , Técnicas de Tipificación Bacteriana , Bacteroidetes/genética , Bacteroidetes/fisiología , Composición de Base , China , Análisis por Conglomerados , Citosol/química , ADN Bacteriano/química , ADN Bacteriano/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Ácidos Grasos/análisis , Concentración de Iones de Hidrógeno , Lagos , Locomoción , Hibridación de Ácido Nucleico , Océanos y Mares , Fosfolípidos/análisis , Filogenia , Quinonas/análisis , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Cloruro de Sodio/metabolismo , Temperatura
17.
Appl Environ Microbiol ; 84(5)2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29269502

RESUMEN

Oxidative stresses commonly exist in natural environments, and microbes have developed a variety of defensive systems to counteract such events. Although increasing evidence has shown that high hydrostatic pressure (HHP) and low temperature (LT) induce antioxidant defense responses in cells, there is no direct evidence to prove the connection between antioxidant defense mechanisms and the adaptation of bacteria to HHP and LT. In this study, using the wild-type (WT) strain of a deep-sea bacterium, Shewanella piezotolerans WP3, as an ancestor, we obtained a mutant, OE100, with an enhanced antioxidant defense capacity by experimental evolution under H2O2 stress. Notably, OE100 exhibited better tolerance not only to H2O2 stress but also to HHP and LT (20 MPa and 4°C, respectively). Whole-genome sequencing identified a deletion mutation in the oxyR gene, which encodes the transcription factor that controls the oxidative stress response. Comparative transcriptome analysis showed that the genes associated with oxidative stress defense, anaerobic respiration, DNA repair, and the synthesis of flagella and bacteriophage were differentially expressed in OE100 compared with the WT at 20 MPa and 4°C. Genetic analysis of oxyR and ccpA2 indicated that the OxyR-regulated cytochrome c peroxidase CcpA2 significantly contributed to the adaptation of WP3 to HHP and LT. Taken together, these results confirmed the inherent relationship between antioxidant defense mechanisms and the adaptation of a benthic microorganism to HHP and LT.IMPORTANCE Oxidative stress exists in various niches, including the deep-sea ecosystem, which is an extreme environment with conditions of HHP and predominantly LT. Although previous studies have shown that HHP and LT induce antioxidant defense responses in cells, direct evidence to prove the connection between antioxidant defense mechanisms and the adaptation of bacteria to HHP and LT is lacking. In this work, using the deep-sea bacterium Shewanella piezotolerans WP3 as a model, we proved that enhancement of the adaptability of WP3 to HHP and LT can benefit from its antioxidant defense mechanism, which provided useful insight into the ecological roles of antioxidant genes in a benthic microorganism and contributed to an improved understanding of microbial adaptation strategies in deep-sea environments.


Asunto(s)
Antioxidantes/metabolismo , Evolución Biológica , Frío , Presión Hidrostática , Shewanella/fisiología , Adaptación Fisiológica , Peróxido de Hidrógeno/farmacología , Shewanella/genética , Estrés Fisiológico , Activación Transcripcional
18.
Toxicol Appl Pharmacol ; 352: 107-118, 2018 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-29660438

RESUMEN

Accumulating evidence has shown that the impact of prenatal environmental factors on the organs of the offspring could last until the adulthood. Here, we aimed to investigate these effects and the potential mechanism of prenatal nicotine exposure (PNE) on the female adult cartilage of the first generation (PNE-F1) and the second generation (PNE-F2). Pregnant Wistar rats were injected with 2.0 mg/kg.d nicotine from gestational day (GD) 9 to 20. Then their F1 generation at GD20 and postnatal week (PW) 12, and F2 generation at PW12 were harvested. The expression of extracellular matrix (ECM) and transforming growth factor ß (TGFß) signaling genes were analyzed by real-time quantitative PCR, and the histone acetylation was examined by chromatin immunoprecipitation assay. The results showed that PNE reduced the ECM and TGFß signaling gene expressions in both PNE-F1 and PNE-F2 female adult articular cartilage. In the F1 generation, PNE inhibited the acetylation at H3K9 of TGFß, TGFß receptor 1 (TGFßR1), SRY-type high mobility group box 9 (SOX9), a1 chain of type II collagen (COL2A1) and aggrecan (ACAN) gene promoters at both GD20 and PW12. In PNE-F2 at PW12, the obvious deacetylation at H3K9 of the TGFßR1 and COL2A1 promoters still existed. Moreover, in rat fetal chondrocytes, corticosterone rather than nicotine directly induced the hypoacetylation of H3K9 of TGFßR1 and COL2A1 genes, which might be the main cause of imperfect cartilage for PNE-F2. This study may be helpful to elucidate the developmental variability of articular cartilage quality and useful for the early prevention of articular damage.


Asunto(s)
Cartílago Articular/efectos de los fármacos , Condrogénesis/efectos de los fármacos , Histonas/metabolismo , Nicotina/toxicidad , Agonistas Nicotínicos/toxicidad , Efectos Tardíos de la Exposición Prenatal , Acetilación , Factores de Edad , Agrecanos/genética , Agrecanos/metabolismo , Animales , Cartílago Articular/metabolismo , Cartílago Articular/patología , Células Cultivadas , Condrocitos/efectos de los fármacos , Condrocitos/metabolismo , Condrocitos/patología , Condrogénesis/genética , Colágeno Tipo II/genética , Colágeno Tipo II/metabolismo , Femenino , Regulación del Desarrollo de la Expresión Génica/efectos de los fármacos , Edad Gestacional , Masculino , Nicotina/administración & dosificación , Agonistas Nicotínicos/administración & dosificación , Embarazo , Ratas Wistar , Receptor Tipo I de Factor de Crecimiento Transformador beta/genética , Receptor Tipo I de Factor de Crecimiento Transformador beta/metabolismo , Transducción de Señal/efectos de los fármacos
19.
BMC Infect Dis ; 18(1): 254, 2018 06 04.
Artículo en Inglés | MEDLINE | ID: mdl-29866105

RESUMEN

BACKGROUND: Female gender and favorable IFNL3 genotypes are the primary independent predictors of spontaneous clearance of HCV infection. However, chronic hepatitis C infection occurs in numerous women carrying favorable IFNL3 genotypes, indicating that other host and/or virological factors contribute to the prognosis of infection. METHODS: A cohort of 137 anti-HCV-positive female Han Chinese cases, including 64 chronic HCV carriers and 73 HCV spontaneous resolvers, was recruited in the study. 111 SNPs in 23 genes encoding HCV co-receptors, transcription factors, Toll-like receptors, co-stimulating molecules, and cytokines were selected for SNP analysis. RESULTS: After comparison of genotypes and allelotype frequencies of 111 SNPs in 23 genes in the primary cohort, the SNPs rs9826 (P = 0.024 for CC/TT/CT; P = 0.015 for C allele/T allele) and rs1521177 (P = 0.017 for GG/TT/GT; P = 0.006 for G allele/T allele) in the RORC gene were significantly associated with spontaneous HCV clearance. In the sub-cohort carrying favorable IFNL3 genotypes (rs12979860CC, rs8099917 TT, rs12980275 AA), rs1521177 (genotype: P = 0.040; allelotype: P = 0.021) remained significantly associated with spontaneous HCV clearance. Importantly, the most common RORC haplotype rs9826-T/rs1521177-T was presented at significantly different frequencies in resolvers and carriers in both the primary cohort (P = 0.0027) and the IFNL3 favorable sub-cohort (P = 0.0117). CONCLUSIONS: This study indicates that genetic polymorphisms in human Th17-related RORC gene are associated with different natural prognosis of HCV infection. The RORC haplotype, rs9826-T/rs1521177-T, was favorable for spontaneous clearance of HCV infection.


Asunto(s)
Hepatitis C Crónica/genética , Miembro 3 del Grupo F de la Subfamilia 1 de Receptores Nucleares/genética , Polimorfismo de Nucleótido Simple , Células Th17/fisiología , Alelos , Pueblo Asiatico/genética , Femenino , Genotipo , Haplotipos , Humanos , Interferones , Interleucinas/genética , Persona de Mediana Edad , Remisión Espontánea , Células Th17/virología
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