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1.
Cell Mol Life Sci ; 80(11): 317, 2023 Oct 06.
Artículo en Inglés | MEDLINE | ID: mdl-37801106

RESUMEN

Hox genes orchestrate the segmental specification of the muscular circulatory system in invertebrates but it has not proven straightforward to decipher segmental parallels in the vertebrate heart. Recently, patients with HOXB gene cluster deletion were found to exhibit abnormalities including atrioventricular canal defects. Using CRISPR, we established a mutant with the orthologous hoxbb cluster deletion in zebrafish. The mutant exhibited heart failure and atrioventricular regurgitation at 5 days. Analyzing the four genes in the hoxbb cluster, isolated deletion of hoxb1b-/- recapitulated the cardiac abnormalities, supporting hoxb1b as the causal gene. Both in situ and in vitro data indicated that hoxb1b regulates gata5 to inhibit hand2 expression and ultimately is required to pattern the vertebrate atrioventricular boundary. Together, these data reveal a role for segmental specification in vertebrate cardiac development and highlight the utility of CRISPR techniques for efficiently exploring the function of large structural genomic lesions.


Asunto(s)
Proteínas de Pez Cebra , Pez Cebra , Animales , Humanos , Pez Cebra/genética , Pez Cebra/metabolismo , Proteínas de Pez Cebra/genética , Proteínas de Pez Cebra/metabolismo , Corazón , Factores de Transcripción/metabolismo , Regulación del Desarrollo de la Expresión Génica
2.
J Clin Pharm Ther ; 46(5): 1373-1381, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34101878

RESUMEN

WHAT IS KNOWN AND OBJECTIVE: We have previously shown that the saponins of Sanguisorba parviflora (Maxim.) Takeda (Sp. T) relieved cyclophosphamide-induced myelosuppression in leukopenic mice. Haematopoietic cell-specific protein 1-associated protein X-1 (HAX-1) participated in the survival of neutrophils through the regulation of mitochondrial function. The aim of the present study was to comprehensively identify the role of HAX-1 in the mechanism of leukopenia alleviation by Sp. T. METHODS: HAX-1 gene and protein expression levels in peripheral blood neutrophils were examined using real-time quantitative reverse transcription-polymerase chain reaction, western blot and immunohistochemical assays. Neutrophil apoptosis was measured using flow cytometry. Mitochondrial function was determined via assessments of the reactive oxygen species (ROS) generation and mitochondrial membrane potential (ΔΨm) integrity levels. RESULTS AND DISCUSSION: The HAX-1 gene expression level in the peripheral blood neutrophils was significantly lower in patients with leukopenia than in healthy donors. The saponins of Sp. T induced HAX-1 expression and promoted myeloid progenitor cell (mEB8-ER cell) viability. HAX-1 overexpression reduced the production of ROS and maintained ΔΨm integrity. Cyclophosphamide-induced mitochondrial dysfunction and apoptosis could be abrogated by treatment with Sp. T or metformin. WHAT IS NEW AND CONCLUSION: Our data suggest a mechanism through which Sp. T protects against chemotherapy-induced leukopenia by regulating HAX-1 gene expression in a mitochondrial-dependent manner.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Ciclofosfamida/efectos adversos , Leucopenia/inducido químicamente , Leucopenia/tratamiento farmacológico , Sanguisorba/química , Saponinas/farmacología , Adulto , Apoptosis/efectos de los fármacos , Femenino , Humanos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Persona de Mediana Edad , Células Progenitoras Mieloides/efectos de los fármacos , Neutrófilos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
3.
J Clin Pharm Ther ; 46(5): 1334-1342, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34075619

RESUMEN

WHAT IS KNOWN AND THE OBJECTIVE: Our previous studies have shown that saponins of Sanguisorba parviflora (Maxim) Takeda (Sp. T) relieved cyclophosphamide-induced myelosuppression in mice with leukopenia. The hematopoietic cell-specific protein 1-associated protein X-1 (HAX-1) participated in the survival of neutrophils through the regulation of mitochondrial function. This study aimed to comprehensively identify the role of HAX-1 in Sp. T to alleviate leukopenia. METHODS: HAX-1 expression was examined in the peripheral blood neutrophils using real-time polymerase chain reaction (PCR), Western blot analysis and immunohistochemical staining. Neutrophil apoptosis was measured by flow cytometry. Mitochondrial function was evaluated via reactive oxygen species (ROS) generation and mitochondrial membrane potential (ΔΨm) integrity. RESULTS AND DISCUSSION: Our study indicated that the expression of the HAX-1 gene was significantly decreased in the peripheral blood neutrophils of leukopenia patients compared with healthy donors. The saponins of Sp. T induced HAX-1 expression and promoted myeloid progenitor cell (mEB8-ER cell) viability, while overexpression of HAX-1 reduced the production of reactive oxygen species (ROS) and maintained the integrity of the mitochondrial membrane potential. Cyclophosphamide-induced mitochondrial dysfunction and apoptosis could be abrogated by treatment with Sp. T or the addition of metformin. WHAT IS NEW AND OUR CONCLUSION: Our data support a mechanism where Sp. T protects against chemotherapy-induced leukopenia by regulating HAX-1 gene expression in a mitochondrial-dependent manner.


Asunto(s)
Proteínas Adaptadoras Transductoras de Señales/biosíntesis , Ciclofosfamida/efectos adversos , Leucopenia/inducido químicamente , Leucopenia/tratamiento farmacológico , Sanguisorba/química , Saponinas/farmacología , Adulto , Apoptosis/efectos de los fármacos , Femenino , Humanos , Masculino , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Persona de Mediana Edad , Neutrófilos/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo
4.
J Card Surg ; 36(7): 2510-2517, 2021 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-33928681

RESUMEN

BACKGROUND: Patients with aortic dissection during pregnancy and postpartum period exhibit a high mortality. At present, a complete overview of aortic dissection during pregnancy and postpartum period is lacking. ​Methods: This systematic review included 80 reports published from 2000 to 2020, comprising a total study population of 103 patients with aortic dissection. ​Results: We found that Stanford Type A aortic dissection was more common in prepartum cases, especially in the third trimester, while postpartum cases of aortic dissection were more common in Stanford Type B. The most common risk factor was connective tissue disease, with no other known risk factors. The mode of delivery had no significant effect on the type of postpartum aortic dissection. Reduced maternal and fetal mortality was observed when patients with Stanford Type A aortic dissection occurring after 28 gestational weeks underwent cesarean section followed by aortic replacement. Patients with Stanford Type B aortic dissection were treated mainly with medication and/or endovascular repair. ​Conclusion: Contemporary management of patients during pregnancy and within 12 weeks postpartum requires multidisciplinary cooperation and includes serial, noninvasive imaging, biomarker testing, and genetic risk profiling for aortopathy. Early diagnosis and accurate treatment are essential to reduce maternal and fetal mortality.


Asunto(s)
Disección Aórtica , Complicaciones Cardiovasculares del Embarazo , Disección Aórtica/diagnóstico por imagen , Disección Aórtica/cirugía , Cesárea , Femenino , Humanos , Periodo Posparto , Embarazo , Tercer Trimestre del Embarazo
5.
J Cell Biochem ; 121(2): 1901-1910, 2020 02.
Artículo en Inglés | MEDLINE | ID: mdl-31633244

RESUMEN

PURPOSE: The aim of this study was to screen survival-related genes for glioblastoma (GBM). METHODS: GSE53733 was downloaded from Gene Expression Omnibus (GEO) database, including 16 short-term (ST), 31 intermediate (IM), and 23 long-term (LT) survivors. Analysis of variance was used to analyze the expression in three groups. The genes with P < .01 were screened as differentially expressed genes (DEGs). Soft clustering was performed using Mfuzz to mine the expression patterns of differential genes in three groups of overall survival (OS) classification. The cytoscape plugin clueGO was used for functional enrichment analysis. The protein interaction between differential genes was extracted from the STRING V10 database, and the protein-protein interaction (PPI) network was constructed and displayed with cytoscape. The hub genes were verified by quantitative reverse-transcription polymerase chain reaction. RESULTS: Total 662 DEGs were obtained among three groups and enriched in 12 clusters. The overlap analysis between clusters could classify these 12 clusters Cluster A and B. Total 264 OS.DEGs were contained in Cluter A and Cluster B, and enriched in 28 Gene Ontology terms, such as trophoblast giant cell differentiation (P value = 6.18E-04), muscle fiber development (P value = 9.09E-04), and negative regulation of stem cell differentiation (P value = 1.76E-03). The top five nodes with highest degree in OS.PPI were HDAC1, DECR1, RASL11A, PDIA3, and POLR2F. The expression of DECR1 and POLR2F was significantly lower, while the levels of HDAC1 and PDIA3 were highly expressed in GBM tissues. CONCLUSION: DECR1, POLR2F, HDAC1, and PDIA3 might be potential key genes affected the overall survival time of patients with GBM.


Asunto(s)
Biomarcadores de Tumor/genética , Regulación Neoplásica de la Expresión Génica , Redes Reguladoras de Genes , Glioblastoma/mortalidad , Femenino , Perfilación de la Expresión Génica , Glioblastoma/genética , Glioblastoma/patología , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Mapas de Interacción de Proteínas , Tasa de Supervivencia
6.
Exp Cell Res ; 379(1): 30-47, 2019 06 01.
Artículo en Inglés | MEDLINE | ID: mdl-30894280

RESUMEN

Pancreatic cancer is one of the most malignant tumors. Invasion and metastasis can occur in the early stage of pancreatic cancer, contributing to the poor prognosis. Accordingly, in this study, we evaluated the molecular mechanisms underlying invasion and metastasis. Using mass spectrometry, we found that Integrin alpha 6 (ITGA6) was more highly expressed in a highly invasive pancreatic cancer cell line (PC-1.0) than in a less invasive cell line (PC-1). Through in vitro and in vivo experiments, we observed significant decreases in invasion and metastasis in pancreatic cancer cells after inhibiting ITGA6. Based on data in TCGA, high ITGA6 expression significantly predicted poor prognosis. By using Co-IP combined mass spectrometry, we found that ribosomal protein SA (RPSA), which was also highly expressed in PC-1.0, interacted with ITGA6. Similar to ITGA6, high RPSA expression promoted invasion and metastasis and indicated poor prognosis. Interestingly, although ITGA6 and RPSA interacted, they did not mutually regulate each other. ITGA6 and RPSA affected invasion and metastasis via the PI3K and MAPK signaling pathways, respectively. Inhibiting ITGA6 significantly reduced the expression of p-AKT, while inhibiting RPSA led to the downregulation of p-ERK1/2. Compared with the inhibition of ITGA6 or RPSA alone, the downregulation of both ITGA6 and RPSA weakened invasion and metastasis to a greater extent and led to the simultaneous downregulation of p-AKT and p-ERK1/2. Our research indicates that the development of drugs targeting both ITGA6 and RPSA may be an effective strategy for the treatment of pancreatic cancer.


Asunto(s)
Integrina alfa6/genética , Sistema de Señalización de MAP Quinasas/genética , Metástasis de la Neoplasia/genética , Neoplasias Pancreáticas/genética , Fosfatidilinositol 3-Quinasas/genética , Receptores de Laminina/genética , Proteínas Ribosómicas/genética , Transducción de Señal/genética , Línea Celular Tumoral , Movimiento Celular/genética , Proliferación Celular/genética , Regulación hacia Abajo/genética , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Invasividad Neoplásica/genética , Invasividad Neoplásica/patología , Metástasis de la Neoplasia/patología , Neoplasias Pancreáticas/patología , Pronóstico , Proteínas Proto-Oncogénicas c-akt/genética
7.
Int J Syst Evol Microbiol ; 69(11): 3485-3491, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31460856

RESUMEN

Two novel, Gram-stain-positive, non-motile, facultatively anaerobic, rod-shaped bacteria (strains 2129T and 2119) were isolated from the faeces of Tibetan antelopes (Pantholops hodgsonii) on the Qinghai-Tibet Plateau, PR China. The 16S rRNA gene sequences of the strains showed highest similarity values to Actinomyces timonensis DSM 23838T (92.9 and 92.8 %, respectively), and phylogenetic analysis based on 16S rRNA gene and genomic sequences indicated that strains 2129T and 2119 represent a new lineage. Strains 2129T and 2119 could ferment d-adonitol and d-xylose, but were unable to utilize d-mannose and d-melibiose nor produce esterase (C4) and proline arylamidase. The G+C contents of the two strains were both 69.0 mol%. Their genomes exhibited less than 40.4 % relatedness in DNA-DNA hybridization tests (below 70 % as the recommended threshold for new species) with all available genomes of the genus Actinomyces in the NCBI database. The major fatty acids of the two strains were C18 : 1ω9c and C16 : 0, and the major polar lipids were diphosphatidylglycerol, glycolipid, phosphatidylinositol, phosphatidyl inositol mannoside and phosphoglycolipid. Based on the results of genotypic, phenotypic and biochemical analyses, it is proposed that the two unidentified bacteria be classified as representing a novel species, Actinomyces lilanjuaniae sp. nov. The type strain is 2129T (=CGMCC 4.7483T=DSM 106426T).


Asunto(s)
Actinomyces/clasificación , Antílopes/microbiología , Filogenia , Actinomyces/aislamiento & purificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Heces/microbiología , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tibet
8.
Cancer Sci ; 109(9): 2946-2956, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30007115

RESUMEN

Pancreatic cancer is one of the deadliest cancers with rapid disease progression. Further elucidation of its underlying molecular mechanisms and novel biomarkers for early detection is necessary. Exosomes are small extracellular vesicles that are released by multiple cell types acting as message carriers during intercellular communication and are promising biomarker candidates. However, the role of pancreatic cancer cell-derived exosomes in cancer progression and the application of these vesicles as novel diagnostic biomarkers have not been fully studied. In this study, we found that PC-1.0 (a highly malignant pancreatic cell line) cell-derived exosomes could be taken up by and enhance PC-1 (a moderately malignant pancreatic cell line) cell proliferation, migration and invasion abilities. We identified ZIP4 as the most upregulated exosomal protein in PC-1.0 cells from our proteomic analysis. In vitro and in vivo (a subcutaneous BALB/c nude mouse model) studies showed that exosomal ZIP4 can significantly promote pancreatic cancer growth. Using clinical blood samples, we compared the diagnostic values of serum exosomal ZIP4 levels between malignant pancreatic cancer patients (n = 24) and benign pancreatic disease patients (n = 32, AUC = .89), and between biliary disease patients (n = 32, AUC = .8112) and healthy controls (n = 46, AUC = .8931). In conclusion, exosomal ZIP4 promotes cancer growth and is a novel diagnostic biomarker for pancreatic cancer.


Asunto(s)
Biomarcadores de Tumor/sangre , Proteínas de Transporte de Catión/fisiología , Exosomas , Neoplasias Pancreáticas/diagnóstico , Animales , Proteínas de Transporte de Catión/sangre , Línea Celular Tumoral , Movimiento Celular , Proliferación Celular , Femenino , Humanos , Mesocricetus , Ratones , Ratones Endogámicos BALB C , Invasividad Neoplásica , Neoplasias Pancreáticas/patología , Proteómica
9.
Mol Cell Biochem ; 446(1-2): 43-52, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29322353

RESUMEN

Impaired myocardial contractile function, one of the well-documented features of sepsis, contributes greatly to the high rate of mortality. Quercetin is widely accepted as a potential antioxidant and free radical scavenger. Epidemiologic studies have suggested that an increase in the intake of dietary Quercetin can reduce the risk of cardiac disease. However, presently there is no report yet on the influence of Quercetin on LPS-induced myocardial dysfunction in vivo. Cardiovascular protective effects of Quercetin on LPS-induced sepsis in mice were measured after intragastric administration, using normal saline as a positive control. Quercetin pretreatment significantly alleviated LPS-induced cardiac abnormalities in mice. The histopathologic findings in the present study justify the findings reported from the biochemical analyses. Our observation from the present research work reveals that Quercetin suppressed the production of proinflammatory cytokines at different levels, such as TNF-α and IL-1ß, and inhibits the activation of I-κB phosphorylation, whereas the total content was not affected. Apoptotic pathways are related to Quercetin protection in the development of myocardial dysfunction. In conclusion, our findings demonstrate the adjuvant potentials of Quercetin for clinical sepsis treatment.


Asunto(s)
Cardiotónicos/farmacología , Regulación de la Expresión Génica/efectos de los fármacos , Interleucina-1beta/metabolismo , Lipopolisacáridos/toxicidad , Miocardio/metabolismo , FN-kappa B/metabolismo , Quercetina/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Apoptosis/efectos de los fármacos , Inflamación/inducido químicamente , Inflamación/metabolismo , Inflamación/patología , Masculino , Ratones , Ratones Endogámicos BALB C , Miocardio/patología , Sepsis/inducido químicamente , Sepsis/metabolismo , Sepsis/patología , Sepsis/prevención & control
10.
Int J Syst Evol Microbiol ; 68(12): 3701-3706, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30351263

RESUMEN

A novel, Gram-stain-positive, catalase-positive, non-spore-forming, short rod-shaped strain (VUL4_3T) was isolated from rectal swabs of Old World vultures (Aegypius monachus) from the Tibet-Qinghai Plateau, China. Based on the results of biochemical tests and 16S rRNA gene sequence comparison, strain VUL4_3T was determined to be a member of the genus Actinomyces that is closely related to the type strains of Actinomyces liubingyangii (97.7 % 16S rRNA gene sequence similarity) and Actinomyces marimammalium (96.5 %). Optimal growth occurred at 37 °C, pH 6-7 and with 1 % (w/v) NaCl. The typical major cellular fatty acids of strain VUL4_3T were C18 : 1ω9c, C16 : 0 and C18 : 0. The VUL4_3T genome contained 2 207 832 bp with an average G+C content of 51.9 mol%. DNA-DNA hybridization values between strain VUL4_3T and the above two species of the genus Actinomyces showed less than 32 % DNA-DNA relatedness, supporting a novel species status of strain VUL4_3T. Based on the phenotypic data and phylogenetic inference, the novel species Actinomycestangfeifanii sp. nov. is proposed. The type strain is VUL4_3T (=CGMCC 4.7369T=DSM 103436T).


Asunto(s)
Actinomyces/clasificación , Falconiformes/microbiología , Filogenia , Actinomyces/genética , Actinomyces/aislamiento & purificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Recto/microbiología , Análisis de Secuencia de ADN
11.
Echocardiography ; 35(2): 153-161, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29178142

RESUMEN

OBJECTIVE: Pulmonary hypertension (PH) impairs right ventricular (RV) systolic and diastolic function, which in turn induces compensatory changes in right atrial (RA) function; the diverse effects on RA function are subject to much debate. We hypothesized that RA function plays a more important role in compensating RV dysfunction, than mere prevention of clinical failure in patients with PH. METHODS: We studied 54 patients with PH and 23 healthy controls. RA volume, including maximum RA volume, minimum RA volume, and the volume before atrial systole, was evaluated by 3DE. RA maximum volume index (Vmax I), total emptying volume index (TotEVI), passive emptying volume index (PassEVI), and active ejection fraction (ActEF) were calculated. Receiver operating characteristic curve analysis was used to determine the sensitivity and specificity of various cutoff levels of the variables measured for predicting World Health Organization functional class (WHO-FC) IV in patients with PH. RESULTS: RAVmax I in patients with PH was higher than that in controls. In patients with PH, the TotEVI was significantly higher, while PassEVI was significantly lower as compared to that in controls. ActEF was increased in patients with WHO functional class (WHO-FC) III PH as compared to that in controls (P = .003) but was reduced in more advanced cases (WHO-FC IV). In addition, the area under the curve of 3D RA ActEF was larger than those of 2D RA ActEF, RA GLS, RA area, FAC, TAPSE, and RIMP (P < .01 for all) for predicting WHO-FC IV. CONCLUSION: We demonstrated that RA function plays a more important role in compensating RV dysfunction then mere prevention of clinical failure in PH.


Asunto(s)
Ecocardiografía Tridimensional/métodos , Hipertensión Pulmonar/fisiopatología , Disfunción Ventricular Derecha/diagnóstico por imagen , Disfunción Ventricular Derecha/fisiopatología , Adulto , Femenino , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Humanos , Hipertensión Pulmonar/complicaciones , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Disfunción Ventricular Derecha/complicaciones
12.
Artículo en Inglés | MEDLINE | ID: mdl-29667273

RESUMEN

An administrative border might hinder the optimal allocation of a given set of resources by restricting the flow of goods, services, and people. In this paper, we address the question: Do administrative borders lead to poor accessibility to public service? In answering the question, we have examined the case of Sweden and its regional administrative borders and hospital accessibility. We have used detailed data on the Swedish road network, its hospitals, and its geo-coded population. We have assessed the population's spatial accessibility to Swedish hospitals by computing the inhabitants' distance to the nearest hospital. We have also elaborated several scenarios ranging from strongly confining regional borders to no confinements of borders and recomputed the accessibility. Our findings imply that administrative borders are only marginally worsening the accessibility.

13.
Int J Syst Evol Microbiol ; 67(9): 3363-3368, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-28857023

RESUMEN

Two strains (pika_113T and pika_114) of a previously undescribed Actinomyces-like bacterium were recovered from the intestinal contents of plateau pika (Ochotona curzoniae) on the Tibet-Qinghai Plateau, China. Results from biochemical characterization indicated that the two strains were phenotypically homogeneous and distinct from other previously described species of the genus Actinomyces. Based on the comparison of 16S rRNA gene sequences and genome analysis, the bacteria were determined to be a hitherto unknown subline within the genus Actinomyces, being most closely related to type strains of Actinomyces denticolens and Actinomyces timonensis with a respective 97.2 and 97.1 % similarity in their 16S rRNA gene sequences. Phylogenetic analyses confirmed that pika_113T was well separated from any other recognized species of the genus Actinomyces and within the cluster with A. denticolens and A. timonensis. The genome of strain pika_113T displayed less than 42 % relatedness in DNA-DNA hybridization with all the available genomes of existing species of the genus Actinomyces in the NCBI database. Collectively, based on the phenotypic characteristics and phylogenetic analyses results, we propose the novel isolates as representatives of Actinomyces gaoshouyii sp. nov. The type strain of Actinomyces gaoshouyii is pika_113T (=CGMCC 4.7372T=DSM 104049T), with a genomic DNA G+C content of 71 mol%.


Asunto(s)
Actinomyces/clasificación , Intestinos/microbiología , Lagomorpha/microbiología , Filogenia , Actinomyces/genética , Actinomyces/aislamiento & purificación , Animales , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Tibet
14.
Int J Syst Evol Microbiol ; 67(6): 1873-1879, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28629506

RESUMEN

Two strains (VUL4_1T and VUL4_2) of Gram-staining-positive, catalase-negative, non-spore-forming short rods were isolated from rectal swabs of Old World vultures (Gypaetus barbatus) in the Tibet-Qinghai Plateau, China. Analysis of morphological characteristics and biochemical tests indicated that the two strains closely resembled each other but were distinct from other species of the genus Actinomyces previously described. Based on the results of 16S rRNA gene sequence comparison and genome analysis, strains were determined to be members of the genus Actinomyces, closely related to the type strains of Actinomyces marimammalium (96.4 % 16S rRNA gene sequence similarity), Actinomyceshongkongensis (92.4 %), Actinomyceshordeovulneris (92.3 %) and Actinomycesnasicola (92.2 %), respectively. Optimal growth conditions were 37 °C, pH 6-7, with 1 % (w/v) NaCl. Strain VUL4_1T contained C18 : 1ω9c and C16 : 0 as the major cellular fatty acids and diphosphatidylglycerol as the major component of the polar lipids. The genomic DNA G+C content of VUL4_1T was 54.9 mol%. Strain VUL4_1T showed less than 70 % DNA-DNA relatedness with other species of the genus Actinomyces, further supporting strain VUL4_1T as a representative of a novel species. Based on the phenotypic data and phylogenetic inference, a novel species, Actinomyces liubingyangii sp. nov., is proposed with VUL4_1T (=CGMCC 4.7370T=DSM 104050T) as the type strain.


Asunto(s)
Falconiformes/microbiología , Filogenia , Recto/microbiología , Actinomyces/genética , Actinomyces/aislamiento & purificación , Animales , Técnicas de Tipificación Bacteriana , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , Fosfolípidos/química , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Compuestos de Espiro , Tibet
15.
Int J Syst Evol Microbiol ; 67(6): 1720-1726, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28629509

RESUMEN

Two strains of Gram-stain-positive, facultatively anaerobic, non-spore-forming short rods (VUL7T and VUL8) were isolated from rectal swabs of Old World vultures, namely Gyps himalayensis, in Tibet-Qinghai Plateau, China. Optimal growth occurred at 37 °C, pH 6-7, with 1 % (w/v) NaCl. Phylogenetic analysis based on 16S rRNA gene sequences classified the two strains to the genus Actinomyces, with highest 16S rRNA gene sequence similarity (95 %) to type strains of Actinomyces haliotis, Actinomyces radicidentis and Actinomyces urogenitalis. The major cellular fatty acids were C18 : 1ω9c and C16 : 0. MK-10(H4) was the major respiratory quinone. The genomic DNA G+C content of the isolate was 54.4 mol%. DNA-DNA hybridization values with the most closely related species ofthe genusActinomyces was 24.6 %. The two strains can be differentiated from the most closely related species such as A. haliotis, A. radicidentis, A. graevenitzii and A. urogenitalis by a list of carbohydrate fermentations and enzyme activities. On the basis of physiological, biochemical and phylogenetic analysis, strains VUL7T and VUL8 represent novel species of the genus Actinomyces, for which the name Actinomyces vulturis sp. nov. is proposed. The type strain is VUL7T (=CGMCC 4.7366T=DSM 103437T).


Asunto(s)
Actinomyces/clasificación , Falconiformes/microbiología , Filogenia , Actinomyces/genética , Actinomyces/aislamiento & purificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , ADN Bacteriano/genética , Ácidos Grasos/química , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Recto/microbiología , Análisis de Secuencia de ADN , Tibet , Ubiquinona/química
16.
Int J Syst Evol Microbiol ; 66(9): 3281-3286, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27226124

RESUMEN

Two bacterial strains were isolated from faecal samples of Tibetan antelopes. The isolates were Gram-stain-positive, catalase-negative, coccus-shaped organisms that were tentatively identified as representing a novel streptococcal species based on their morphological features, biochemical test results and phylogenomic findings. Comparative 16S rRNA gene sequencing studies confirmed that the organisms were members of the genus Streptococcus, but they did not correspond to any recognized species of the genus. The nearest phylogenetic relative of the unknown coccus was Streptococcus ursoris NUM 1615T (93.4 % 16S rRNA gene sequence similarity). Analysis of groEL and rpoB gene sequences of the novel isolates showed interspecies divergence of 27.0 and 22.2 %, respectively, from the type strain of its closest 16S rRNA gene phylogenetic relative, S. ursoris. The complete genome of strain TA 26T has been sequenced. Digital DNA-DNA hybridization studies between strain TA 26T and other species of the genus Streptococcus deposited in the GenBank database showed less than 70 % DNA-DNA relatedness, supporting a novel species status of the strain. On the basis of their genotypic and phenotypic differences from recognized Streptococcus species, the two isolates represent a novel species of the genus Streptococcus, for which the nameStreptococcus pantholopis sp. nov. (type strain TA 26T=CGMCC 1.15667T=DSM 102135T) is proposed.


Asunto(s)
Antílopes/microbiología , Filogenia , Streptococcus/clasificación , Animales , Técnicas de Tipificación Bacteriana , Composición de Base , China , ADN Bacteriano/genética , ADN Ribosómico/genética , Ácidos Grasos/química , Heces/microbiología , Genes Bacterianos , Hibridación de Ácido Nucleico , ARN Ribosómico 16S/genética , Análisis de Secuencia de ADN , Streptococcus/genética , Streptococcus/aislamiento & purificación
17.
Polymers (Basel) ; 16(3)2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38337305

RESUMEN

Temperature-responsive separation membranes can significantly change their permeability and separation properties in response to changes in their surrounding temperature, improving efficiency and reducing membrane costs. This study focuses on the modification of polyvinylidene fluoride (PVDF) membranes with amphiphilic temperature-responsive copolymer and inorganic nanoparticles. We prepared an amphiphilic temperature-responsive copolymer in which the hydrophilic poly(N-isopropyl acrylamide) (PNIPAAm) was side-linked to a hydrophobic polyvinylidene fluoride (PVDF) skeleton. Subsequently, PVDF-g-PNIPAAm polymer and graphene oxide (GO) were blended with PVDF to prepare temperature-responsive separation membranes. The results showed that temperature-responsive polymers with different NIPAAm grafting ratios were successfully prepared by adjusting the material ratio of NIPAAm to PVDF. PVDF-g-PNIPAAm was blended with PVDF with different grafting ratios to obtain separate membranes with different temperature responses. GO and PVDF-g-PNIPAAm formed a relatively stable hydrogen bond network, which improved the internal structure and antifouling performance of the membrane without affecting the temperature response, thus extending the service life of the membrane.

18.
ACS Omega ; 9(7): 7937-7957, 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38405476

RESUMEN

In the context of global climate change, significant attention is being directed toward renewable energy and the pivotal role of carbon capture and storage (CCS) technologies. These innovations involve secure CO2 storage in deep saline aquifers through structural and capillary processes, with the interfacial tension (IFT) of the CO2-brine system influencing the storage capacity of formations. In this study, an extensive data set of 2811 experimental data points was compiled to model the IFT of impure and pure CO2-brine systems. Three white-box machine learning (ML) methods, namely, genetic programming (GP), gene expression programming (GEP), and group method of data handling (GMDH) were employed to establish accurate mathematical correlations. Notably, the study utilized two distinct modeling approaches: one focused on impurity compositions and the other incorporating a pseudocritical temperature variable (Tcm) offering a versatile predictive tool suitable for various gas mixtures. Among the correlation methods explored, GMDH, employing five inputs, exhibited exceptional accuracy and reliability across all metrics. Its mean absolute percentage error (MAPE) values for testing, training, and complete data sets stood at 7.63, 7.31, and 7.38%, respectively. In the case of six-input models, the GEP correlation displayed the highest precision, with MAPE values of 9.30, 8.06, and 8.31% for the testing, training, and total data sets, respectively. The sensitivity and trend analyses revealed that pressure exerted the most significant impact on the IFT of CO2-brine, showcasing an adverse effect. Moreover, an impurity possessing a critical temperature below that of CO2 resulted in an elevated IFT. Consequently, this relationship leads to higher impurity concentrations aligning with lower Tcm values and subsequently elevated IFT. Also, monovalent and divalent cation molalities exhibited a growing influence on the IFT, with divalent cations exerting approximately double the influence of monovalent cations. Finally, the Leverage approach confirmed both the reliability of the experimental data and the robust statistical validity of the best correlations established in this study.

19.
Psych J ; 12(3): 421-429, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37186458

RESUMEN

Accurately predicting whether a short video will be liked by viewers is a topic of interest to media researchers. This study used an electroencephalogram (EEG) to record neural activity in 109 participants as they watched short videos (16 clips per person) to see which neural signals reflected viewers' preferences. The results showed that, compared with the short videos they disliked, individuals would experience positive emotions [indexed by a higher theta power, lower (beta - theta)/(beta + theta) score], more relaxed states (indexed by a lower beta power), lower levels of mental engagement and alertness [indexed by a lower beta/(alpha + theta) score], and devote more attention (indexed by lower alpha/theta) when watching short videos they liked. We further used artificial neural networks to classify the neural signals of different preferences induced by short videos. The classification accuracy was the highest when using data from bands over the whole brain, which was 75.78%. These results may indicate the potential of EEG measurement to evaluate the subjective preferences of individuals for short videos.


Asunto(s)
Electroencefalografía , Emociones , Humanos , Electroencefalografía/métodos , Encéfalo
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