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Urease-producing bacteria (UPB) are widely present in soil and play an important role in soil ecosystems. In this study, 65 UPB strains were isolated from cadmium (Cd)-polluted soil around a lead-zinc mine in Yunnan Province, China. The Cd tolerance, removal of Cd from aqueous solution, production of indoleacetic acid (IAA) and plant growth-promoting effects of these materials were investigated. The results indicate that among the 65 UPB strains, four strains with IAA-producing ability were screened and identified as Bacillus thuringiensis W6-11, B. cereus C7-4, Serratia marcescens W11-10, and S. marcescens C5-6. Among the four strains, B. cereus C7-4 had the highest Cd tolerance, median effect concentration (EC50) of 59.94 mg/L. Under Cd 5 mg/L, S. marcescens C5-6 had the highest Cd removal from aqueous solution, up to 69.83%. Under Cd 25 mg/kg, inoculation with B. cereus C7-4 significantly promoted maize growth in a sand pot by increasing the root volume, root surface area, and number of root branches by 22%, 29%, and 20%, respectively, and plant height and biomass by 16% and 36%, respectively, and significantly increasing Cd uptake in the maize roots. Therefore, UPB is a potential resource for enhancing plant adaptability to Cd stress in plants with Cd-polluted habitats.
This study utilized urease-producing bacteria screened from the soil of lead zinc mining areas in Yunnan, China as the research object, enriching the microbial resources in Yunnan. In addition, this article verified the IAA production ability and cadmium removal ability of urease-producing bacteria, and screened out bifunctional urease-producing bacteria that have potential in cadmium pollution control and plant growth promotion.
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Biodegradación Ambiental , Cadmio , Microbiología del Suelo , Contaminantes del Suelo , Ureasa , Zea mays , Cadmio/metabolismo , Contaminantes del Suelo/metabolismo , Zea mays/metabolismo , Ureasa/metabolismo , China , Ácidos Indolacéticos/metabolismo , Serratia marcescens/fisiología , Reguladores del Crecimiento de las Plantas/metabolismoRESUMEN
Myocardial fibrosis (MF) is involved in hypertension, myocardial infarction and heart failure. It has been reported that circular RNA (circRNA) is a key regulatory factor of MF progression. In this study, we revealed that circ_0002295 and CXCR2 were elevated, and miR-1287 was reduced in MF patients. Knockdown of circ_0002295 effectively suppressed the proliferation, migration and MF progression. Circ_0002295 was the molecular sponge of miR-12878, and miR-1287 inhibitor reversed the biological functions of circ_0002295 on the myocardial fibrosis. CXCR2 was a target gene of miR-1287, and CXCR2 silencing relieved the impacts of miR-1287 inhibitor on cardiac myofibroblasts. Circ_0002295 promoted MF progression by regulating the miR-1287/CXCR2 axis, providing a possible circRNA-targeted therapy for MF.
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Insuficiencia Cardíaca , MicroARNs , Infarto del Miocardio , Humanos , Línea Celular Tumoral , Proliferación Celular/genética , Corazón , MicroARNs/genética , Receptores de Interleucina-8B/genética , ARN Circular/genéticaRESUMEN
The identification of additional Echinococcus granulosus sensu lato (s.l.) complex species/genotypes in recent years raises the possibility that there might be more variation among this species in China than is currently understood. The aim of this study was to explore intra- and inter-species variation and population structure of Echinococcus species isolated from sheep in three areas of Western China. Of the isolates, 317, 322, and 326 were successfully amplified and sequenced for cox1, nad1, and nad5 genes, respectively. BLAST analysis revealed that the majority of the isolates were E. granulosus s.s., and using the cox1, nad1, and nad5 genes, respectively, 17, 14, and 11 isolates corresponded to Elodea canadensis (genotype G6/G7). In the three study areas, G1 genotypes were the most prevalent. There were 233 mutation sites along with 129 parsimony informative sites. A transition/transversion ratio of 7.5, 8, and 3.25, respectively, for cox1, nad1, and nad5 genes was obtained. Every mitochondrial gene had intraspecific variations, which were represented in a star-like network with a major haplotype with observable mutations from other distant and minor haplotypes. The Tajima's D value was significantly negative in all populations, indicating a substantial divergence from neutrality and supporting the demographic expansion of E. granulosus s.s. in the study areas. The phylogeny inferred by the maximum likelihood (ML) method using nucleotide sequences of cox1-nad1-nad5 further confirmed their identity. The nodes assigned to the G1, G3, and G6 clades as well as the reference sequences utilized had maximal posterior probability values (1.00). In conclusion, our study confirms the existence of a significant major haplotype of E. granulosus s.s. where G1 is the predominant genotype causing of CE in both livestock and humans in China.
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Equinococosis , Echinococcus granulosus , Animales , Humanos , Ovinos , Echinococcus granulosus/genética , Tibet , Equinococosis/epidemiología , Equinococosis/veterinaria , China , Genotipo , Haplotipos , Mutación , Filogenia , Variación GenéticaRESUMEN
Temozolomide (TMZ) can cross the blood-brain barrier (BBB) and deliver methyl groups to the purine (guanine) bases of DNA, leading to mispairing during DNA replication and subsequent cell death. However, increased expression of the repair enzyme methyl guanine methyltransferase (MGMT), which removes methyl groups from purine bases, counteracts methylation by TMZ. We evaluated the anticancer potential of thymoquinone (TQ), a hydrophobic flavonoid that inhibits resistance and induces apoptosis in various cancer cells, both in vitro and in vivo. In vitro experiments showed that compared with the Hs683 and M059J cell lines, U251 cells were more sensitive to TMZ. Compared to U251 cells, U251R cells, a TMZ drug-resistant strain established in this study, are characterized by increased expression of phosphorylated extracellular signal-regulated kinase (p-ERK) and MGMT. TQ treatments induced apoptosis in all cell lines. The p38 mitogen-activated protein kinase signal pathway was mainly activated in U251 and U251R cells; however, p-ERK and MGMT upregulation could not suppress TQ effects. Furthermore, si-p38 pretreatment of U251R cells in TQ treatments inhibited cell apoptosis. We speculate that TQ contributed to the phosphorylation and activation of p38, but not of ERK-induced apoptosis (irrespective of TMZ resistance). In vivo, U251R-derived tumors subcutaneously inoculated in nude mice exhibited significant tumor volume reduction after TQ or TQ + TMZ cotreatments. High-performance liquid chromatography assay confirmed the presence of TQ in murine brain tissues. Our findings demonstrate that TQ can effectively cross the BBB and function alone or in combination with TMZ to treat glioblastoma.
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Neoplasias Encefálicas , Glioblastoma , Ratones , Animales , Temozolomida/farmacología , Temozolomida/uso terapéutico , Glioblastoma/patología , Dacarbazina/farmacología , Dacarbazina/uso terapéutico , Ratones Desnudos , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Línea Celular Tumoral , Resistencia a Antineoplásicos , Apoptosis , Transducción de Señal , Purinas/farmacología , Purinas/uso terapéutico , Guanina/farmacología , Guanina/uso terapéutico , Antineoplásicos Alquilantes/farmacología , Neoplasias Encefálicas/metabolismoRESUMEN
BACKGROUND The digestive tract is the most common site of extranodal involvement in diffuse large B cell lymphoma (DLBCL) and its prognostic evaluation is different from that of ordinary DLBCL. Currently, for gastrointestinal lymphoma, in addition to the Ann Arbor staging system, the Lugano and the TNM staging systems are commonly used. However, there is no effective prognostic model to identify poor prognosis in patients with localized gastrointestinal diffuse large B cell lymphoma (GI-DLBCL). MATERIAL AND METHODS This study included 82 patients with GI-DLBCL that had a median follow-up of 75 months, and developed a model (HLAMA) with 5 variables: hemoglobin, age, lactate dehydrogenase (LDH), serum albumin, and the maximum intra-abdominal lesion diameter (MIALD). The specific indicators are: HGB <105 g/L (2 points); LDH ≥300 U/L; age ≥75 years, ALB <38 g/L, MIALD ≥4 cm (each scoring 1 point). We also developed a simplified model, which includes only 3 variables (HGB, LDH, and age). RESULTS HLAMA model and the simplified model both demonstrated good ability to predict prognosis of patients with GI-DLBCL (P<0.001), performing better than the IPI score as it could distinguish low-risk groups in relatively elderly patients (60-75 years old). CONCLUSIONS This study established a prognostic model for diffuse large B cell lymphoma of the gastrointestinal tract. Both the HLAMA model and its simplified version are similar to the IPI score, but could be considered better as they can provide a simpler and more accurate prognostic assessment in patients with GI-DLBCL. For patients with localized GI-DLBCL, our model could distinguish high-risk patients.
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Neoplasias Gastrointestinales/patología , Linfoma de Células B Grandes Difuso/patología , Modelos Estadísticos , Estadificación de Neoplasias/normas , Anciano , Terapia Combinada , Femenino , Estudios de Seguimiento , Neoplasias Gastrointestinales/terapia , Humanos , Linfoma de Células B Grandes Difuso/terapia , Masculino , Persona de Mediana Edad , Pronóstico , Tasa de SupervivenciaRESUMEN
Although enormous achievements have been made in targeted molecular therapies against hepatocellular carcinoma (HCC), the treatments can only prolong the life of patients with extrahepatic metastases. We evaluated thymoquinone (TQ), a compound from Nigella sativa Linn., for its anti-cancer effect on SK-Hep1 cells and HCC-xenograft nude mice. TQ effectively triggered cell death and activated p38 and extracellular signal-regulated kinases (Erk) pathways up to 24 h after treatment in cells. TQ-induced cell death was reversed by p38 inhibitor; however, it was enhanced by si-Erk. The caspase3 activation and TUNEL assay revealed a stronger toxic effect upon co-treatment with TQ and si-Erk. Our study suggested that phosphorylation of p38 in SK-Hep1 cells constituted the major factor leading to cell apoptosis, whereas phosphorylation of Erk led to drug resistance. Furthermore, TQ therapeutic effect was improved upon Erk inhibition in HCC-xenograft nude mice. TQ could present excellent anti-HCC potential under suitable p-Erk inhibiting conditions.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Animales , Apoptosis , Benzoquinonas , Carcinoma Hepatocelular/tratamiento farmacológico , Línea Celular Tumoral , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Humanos , Neoplasias Hepáticas/tratamiento farmacológico , Ratones , Ratones Desnudos , FosforilaciónRESUMEN
A field experiment in which a hyperaccumulator (Arabis alpina) was intercropped with winter crop (Vicia faba), was conducted to understand effect of the root exudates on the content and accumulated amounts, sub-cellular distribution of Cd and Pb of the intercropped plants during the ripening period of V. faba (120 d after sowing). The results showed that contents of soluble sugars exuded from the roots of intercropped A. alpina were 67.6% less than that of the monocropped plant, whereas contents of free amino acids was 57.9% greater. The total contents of organic acids exuded from roots of intercropped A. alpina and V. faba were 578.8% and 37.8% greater than that of monocropped plants, respectively. The contents of tartaric acid and malic acid exuded by roots of intercropped A. alpina were greater 31.9 times and 15.9 times than those of monocropped A. alpina, respectively. The contents and accumulated amounts of Cd and Pb in intercropped A. alpina were greater than those of monocropped A. alpina. The contents of Pb bound to organic matter in cell walls, cytoplasm and organelles of intercropped plants were greater than those of monocropped plants. These results demonstrate that increases in accumulated amounts of Pb and Cd caused by intercropping were closely related to migration of Cd and Pb in plants mediated by the composition and content of the root exudates.
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Arabis , Vicia faba , Biodegradación Ambiental , Cadmio , Plomo , Raíces de Plantas , TriticumRESUMEN
Based on the structural scaffolds of natural products, two series of flavonoid derivatives, for a total of twelve compounds, were designed and synthesized as potential human telomerase inhibitors. Using a modified TRAP-PCR assay, compound 5c exhibited the most potent inhibitory activity against human telomerase with an IC50 value of less than 50 µM. In vitro, the results demonstrated that compound 5c had potent anticancer activity against five classes of tumor cell lines. The molecular docking and molecular dynamics analyses binding to the human telomerase holoenzyme were performed to elucidate the binding mode of active compound 5c. This finding helps the rational design of more potent telomerase inhibitors based on the structural scaffolds of natural products.
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Diseño de Fármacos , Inhibidores Enzimáticos/síntesis química , Inhibidores Enzimáticos/farmacología , Flavonoides/síntesis química , Flavonoides/farmacología , Simulación del Acoplamiento Molecular , Telomerasa/antagonistas & inhibidores , Sitios de Unión , Línea Celular Tumoral , Proliferación Celular/efectos de los fármacos , Inhibidores Enzimáticos/química , Flavonoides/química , Humanos , Concentración 50 Inhibidora , Ligandos , Telomerasa/metabolismoRESUMEN
Proline-rich transmembrane protein 2 gene (PRRT2) mutations are reported to cause common paroxysmal neurological disorders and show a remarkable pleiotropy. Benign epilepsy with centrotemporal spikes (BECTS) is considered to be the most common epilepsy syndrome in childhood. It is placed among the idiopathic localization related epilepsies. Recently, it was reported that a girl with a PRRT2 mutation c.649_650insC developed infantile focal epilepsy with bilateral spikes which resembled the rolandic spikes. Hereby we performed a comprehensive genetic mutation screening of PRRT2 gene in a cohort of 53 sporadic BECTS patients. None of the 53 sporadic BECTS patients and other 250 controls carried mutations including c.649_650insC in PRRT2. Our data indicated that the PRRT2 mutations might most likely not be associated with BECTS in Chinese mainland population.
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Epilepsia Rolándica/genética , Proteínas de la Membrana/genética , Proteínas del Tejido Nervioso/genética , Adolescente , Niño , Preescolar , China , Femenino , Humanos , Masculino , MutaciónRESUMEN
A series of novel N-substituted-ß-d-glucosamine derivatives that incorporate benzenesulfonamides were designed using a fragment-based drug design strategy. Each derivative was synthesized and evaluated in vitro for its inhibitory activity against human carbonic anhydrase (hCA) IX; several derivatives displayed desirable potency profiles against this enzyme. The molecular docking studies provided the design rationale and predicted potential binding modes for carbonic anhydrase (CA) IX and three target compounds, including the most potent inhibitor, compound 7f (IC50 = 10.01 nM). Moreover, the calculated Log P (cLog P) values showed that all the compounds tended to be hydrophilic. In addition, topological polar surface area (TPSA) value-based predictions highlighted the selectivity of these carbohydrate-based inhibitors for membrane-associated CA IX.
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Anhidrasa Carbónica IX/antagonistas & inhibidores , Inhibidores de Anhidrasa Carbónica/farmacología , Galactosamina/análogos & derivados , Glucosamina/análogos & derivados , Sulfonamidas/síntesis química , Antígenos de Neoplasias/metabolismo , Anhidrasa Carbónica IX/metabolismo , Diseño de Fármacos , Galactosamina/síntesis química , Galactosamina/química , Galactosamina/farmacología , Humanos , Simulación del Acoplamiento Molecular , Estructura Molecular , Relación Estructura-Actividad , Sulfonamidas/química , Sulfonamidas/farmacología , BencenosulfonamidasRESUMEN
Multiple system atrophy, a sporadic neurodegenerative disease, is characterized by the presence of high numbers of glial cytoplasmic inclusions mainly formed by α-synuclein protein, which is encoded by the SNCA gene. To date, however, few studies have investigated the plasma α-synuclein levels in patients with multiple system atrophy. We studied plasma α-synuclein concentrations by using an enzyme-linked immunosorbent assay in 74 patients with multiple system atrophy and 90 healthy controls. The plasma α-synuclein levels were significantly elevated in patients who had multiple system atrophy compared with the control group (P = 0.000). In a subgroup of 48 patients who had probable multiple system atrophy, there was a weakly negative correlation between plasma α-synuclein levels and subscores on Unified Multiple System Atrophy Rating Scale item VI (r(s) = -0.307; P = 0.034). Plasma α-synuclein levels were elevated in patients with multiple system atrophy, and these levels may be decreased with the development of disease.
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Atrofia de Múltiples Sistemas/sangre , alfa-Sinucleína/sangre , Adulto , Anciano , Encéfalo/metabolismo , Encéfalo/patología , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Expresión Génica/fisiología , Humanos , Cuerpos de Inclusión/patología , Masculino , Persona de Mediana Edad , Atrofia de Múltiples Sistemas/genética , alfa-Sinucleína/genéticaRESUMEN
Sensitizers are responsible for the light harvesting and the charge injection in dye-sensitized solar cells (DSSCs). A fast dye-regeneration process is necessary to obtain highly efficient DSSC devices. Herein, dye-regeneration rates of two DSSC device types, that is, the reduction of immediately formed photo-oxidized sensitizers (ruthenium complex C106TBA and porphyrin LD14, k(ox)') by iodide ions (I(-)) and [Co(bpy)3](2+), and the oxidation of formed photo-reduced sensitizers (organic dye P1, k(re)') by triiodide ions (I3(-)) and the disulfide dimer (T2) are investigated by scanning electrochemical microscopy (SECM). We provide a thorough experimental verification of the feedback mode to compare the kinetics for dye-regeneration by using the above mentioned mediators. The charge recombination at the dye/semiconductor/electrolyte interface is further investigated by SECM. A theoretical model is applied to interpret the current response at the tip under short-circuit conditions, providing important information on factors that govern the dynamics of dye-regeneration onto the dye-sensitized heterojunction.
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Over the past decades, the immune responses have been suspected of participating in the mechanisms for epilepsy. To assess the immune related pathway in temporal lobe epilepsy (TLE), we explored the altered immune pathways in TLE patients with and without hippocampal sclerosis (HS). We analyzed RNA-seq data from 3 TLE-HS and 3 TLE-nonHS patients, including identification of differentially expressed RNA, function pathway enrichment, the protein-protein interaction network and construction of ceRNA regulatory network. We illustrated the immune related landscape of molecules and pathways on human TLE-HS. Also, we identified several differential immune related genes like HSP90AA1 and SOD1 in TLE-HS patients. Further ceRNA regulatory network analysis found SOX2-OT connected to miR-671-5p and upregulated the target gene SPP1 in TLE-HS patients. Also, we identified both SOX2-OT and SPP1 were significantly upregulated in five different databases including TLE-HS patients and animal models. Our findings established the first immune related genes and possible regulatory pathways in TLE-HS patients and animal models, which provided a novel insight into disease pathogenesis in both patients and animal models. The immune related SOX2-OT/miR-671-5p/SPP1 axis may be the potential therapeutic target for TLE-HS.
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Epilepsia del Lóbulo Temporal , Redes Reguladoras de Genes , Esclerosis del Hipocampo , MicroARNs , Factores de Transcripción SOXB1 , Adulto , Animales , Femenino , Humanos , Masculino , Epilepsia del Lóbulo Temporal/genética , Epilepsia del Lóbulo Temporal/inmunología , Epilepsia del Lóbulo Temporal/fisiopatología , Perfilación de la Expresión Génica , Esclerosis del Hipocampo/inmunología , Esclerosis del Hipocampo/fisiopatología , MicroARNs/genética , MicroARNs/metabolismo , Osteopontina/genética , Osteopontina/metabolismo , Mapas de Interacción de Proteínas , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismoRESUMEN
Moniezia benedeni and M. expansa are common ruminant tapeworms of worldwide distribution, causing gastrointestinal disorders and even death in sheep and goats. In this study, a polymerase chain reaction- (PCR-) based approach for precise species identification was developed and also applied to faecal DNA diagnosis of the tapeworm infection. Since nuclear ribosomal DNA (rDNA) appears to be a useful target for species and/or strain markers, the 18S regions of the rDNA of M. benedeni and M. expansa were amplified and sequenced. The lengths and GC contents of the regions sequenced were 2476-2487 bp and 51.9-52.1% for M. benedeni and 2473 bp and 51.9-52.0% for M. expansa, respectively. Alignment and comparison of the 18S sequences of the two species showed 92.5-93.3% homology. No matches for the 18S regions of M. benedeni and M. expansa were found with other species by BLAST search, which made the 18S sequences appropriate markers for the design of distinctive primers for the two Moniezia species. Our 18S-based PCR could detect as low levels as 0.5 pg genomic DNA or the DNA extracted from 0.2 g faecal sample collected from the rectum of an M. expansa-infected goat. The results indicate that this PCR approach is a reliable alternative for the differential diagnosis of Moniezia species in faecal samples.
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Cestodos , ADN Ribosómico , Animales , Secuencia de Bases , Infecciones por Cestodos , Diagnóstico Diferencial , Datos de Secuencia Molecular , Reacción en Cadena de la Polimerasa , ARN Ribosómico 18SRESUMEN
Metastasis of osteosarcoma is an important adverse factor affecting patients' survival, and cancer stemness is the crucial cause of distant metastasis. Capsaicin, the main component of pepper, has been proven in our previous work to inhibit osteosarcoma proliferation and enhance its drug sensitivity to cisplatin at low concentrations. This study aims to further explore the anti-osteosarcoma effect of capsaicin at low concentrations (100[Formula: see text][Formula: see text]M, 24[Formula: see text]h) on stemness and metastasis. The stemness of human osteosarcoma (HOS) cells was decreased significantly by capsaicin treatment. Additionally, the capsaicin treatment's inhibition of cancer stem cells (CSCs) was dose-dependent on both sphere formation and sphere size. Meanwhile, capsaicin inhibited invasion and migration, which might be associated with 25 metastasis-related genes. SOX2 and EZH2 were the most two relevant stemness factors for capsaicin's dose-dependent inhibition of osteosarcoma. The mRNAsi score of HOS stemness inhibited by capsaicin was strongly correlated with most metastasis-related genes of osteosarcoma. Capsaicin downregulated six metastasis-promoting genes and up-regulated three metastasis-inhibiting genes, which significantly affected the overall survival and/or disease-free survival of patients. In addition, the CSC re-adhesion scratch assay demonstrated that capsaicin inhibited the migration ability of osteosarcoma by inhibiting its stemness. Overall, capsaicin exerts a significant inhibitory effect on the stemness expression and metastatic ability of osteosarcoma. Moreover, it can inhibit the migratory ability of osteosarcoma by suppressing its stemness via downregulating SOX2 and EZH2. Therefore, capsaicin is expected to be a potential drug against osteosarcoma metastasis due to its ability to inhibit cancer stemness.
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Neoplasias Óseas , Osteosarcoma , Humanos , Capsaicina/farmacología , Capsaicina/uso terapéutico , Capsaicina/metabolismo , Proliferación Celular/genética , Línea Celular Tumoral , Osteosarcoma/tratamiento farmacológico , Osteosarcoma/genética , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Células Madre Neoplásicas/patología , Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Proteína Potenciadora del Homólogo Zeste 2/farmacología , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , Factores de Transcripción SOXB1/farmacologíaRESUMEN
PM2.5 and ozone co-pollution, which are harmful to not only human health but also the social economy, has become the pivotal issue in air pollution prevention and synergistic control, especially in Beijing-Tianjin-Hebei and its surrounding areas and "2+26" cities. It is necessary to analyze the correlation between PM2.5 and ozone concentration and explore the mechanism of PM2.5 and ozone co-pollution. In order to study the characteristics of PM2.5 and ozone co-pollution in Beijing-Tianjin-Hebei with its surrounding area, ArcGIS and SPSS software were used to analyze the correlation between air quality data and meteorological data of the "2+26" cities in Beijing-Tianjin-Hebei and its surrounding areas from 2015 to 2021. The results indicated:â PM2.5 pollution constantly decreased from 2015 to 2021, and the pollution was concentrated in the central and southern parts of the region; ozone pollution showed a trend of fluctuation and presented a pattern of "low in the southwest and high in the northeast" spatially. In terms of seasonal variation, PM2.5concentration was mainly in the order of winter>spring ≈ autumn>summer, and O3-8h concentration was in the order of summer>spring>autumn>winter. â¡ In the research area, days with PM2.5 exceeding the standard continued to decline, whereas days with ozone exceeding the standard fluctuated, and days with co-pollution decreased significantly; there was a strong positive correlation between PM2.5 and ozone concentration in summer, with the highest correlation coefficient of 0.52, and a strong negative correlation in winter. ⢠Comparing the meteorological conditions of typical cities during the ozone pollution period with that of the co-pollution period, the co-pollution occurred under the temperature range of 23.7-26.5â, humidity of 48%-65%, and S-SE wind direction.
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Vanadium compounds were studied during recent years to be considered as a representative of a new class of nonplatinum metal anticancer agents in combination to its low toxicity. Here, we found a vanadium compound Van-7 as an inhibitor of Topo I other than Topo II using topoisomerase-mediated supercoiled DNA relaxation assay. Agarose gel electrophoresis and comet assay showed that Van-7 treatment did not produce cleavable complexes like HCPT, thereby suggesting that Topo I inhibition occurred upstream of the relegation step. Further studies revealed that Van-7 inhibited Topo I DNA binding involved in its intercalating DNA. Van-7 did not affect the catalytic activity of DNase I even up to100 µM. Van-7 significantly suppressed the growth of cancer cell lines with IC(50) at nanomolar concentrations and arrested cell cycle of A549 cells at G2/M phase. All these results indicate that Van-7 is a potential selective Topo I inhibitor with anticancer activities as a kind of Topo I suppressor, not Topo I poison.
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Gesture recognition utilizes deep learning network model to automatically extract deep features of data; however, traditional machine learning algorithms rely on manual feature extraction and poor model generalization ability. In this paper, a multimodal gesture recognition algorithm based on convolutional long-term memory network is proposed. First, a convolutional neural network (CNN) is employed to automatically extract the deeply hidden features of multimodal gesture data. Then, a time series model is constructed using a long short-term memory (LSTM) network to learn the long-term dependence of multimodal gesture features on the time series. On this basis, the classification of multimodal gestures is realized by the SoftMax classifier. Finally, the method is experimented and evaluated on two dynamic gesture datasets, VIVA and NVGesture. Experimental results indicate that the accuracy rates of the proposed method on the VIVA and NVGesture datasets are 92.55% and 87.38%, respectively, and its recognition accuracy and convergence performance are better than those of other comparison algorithms.
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Gestos , Memoria a Corto Plazo , Algoritmos , Memoria a Largo Plazo , Redes Neurales de la ComputaciónRESUMEN
This paper aims to investigate the mechanism by which dark septate endophytes (DSEs) enhance cadmium (Cd) tolerance in there host plants. Maize (Zea mays L.) was inoculated with a DSE, Exophiala pisciphila, under Cd stress at different concentrations (0, 5, 10, and 20 mg·kg-1). The results show that, under 20 mg/kg Cd stress, DSE significantly increased maize biomass and plant height, indicating that DSE colonization can be utilized to increase the Cd tolerance of host plants. More Cd was retained in DSE-inoculated roots, especially that fixed in the root cell wall (RCW). The capability of DSE to induce a higher Cd holding capacity in the RCW is caused by modulation of the total sugar and uronic acid of DSE-colonized RCW, mainly the pectin and hemicellulose fractions. The fourier-transform spectroscopy analysis results show that carboxyl, hydroxyl, and acidic groups are involved in Cd retention in the DSE-inoculated RCW. The promotion of the growth of maize and improvement in its tolerance to Cd due to DSEs are related to restriction of the translocation of Cd from roots to shoots; resistance of Cd uptake Cd inside cells; and the increase in RCW-integrated Cd through modulating RCW polysaccharide components.
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Composite pile foundation has been widely used in ground engineering. This composite pile foundation system has complex pile-soil interactions under seismic loading. The calculation of vertical bearing capacity of composite pile foundation is still an unsolved problem if the soil around piles is partially or completely liquefied under seismic loading. We have completed indoor shaking table model tests to measure the vertical bearing capacity in a liquefiable soil foundation under seismic loading. This paper will use a numerical approach to analyze the change of this vertical bearing capacity under seismic loading. Firstly, the Goodman contact element is improved to include the Rayleigh damping. Such an improvement can well describe the reflection and absorption of seismic waves at the interface of soil and piles. Secondly, the Biot's dynamic consolidation theory incorporated an elastoplastic model is applied to simulate the soil deformation and the generation and accumulation of pore water pressure under seismic loading. Thirdly, after verification with our indoor shaking table test data, this approach is used to investigate the effects of pile spacing on liquefaction resistance of the composite pile foundation in liquefiable soil. The time histories of pore water pressure ratio (PPR') are calculated for the liquefiable soil and the vertical bearing capacity in partially liquefied soil is calculated and compared with our indoor shaking table test data at the 3D, 3.5D, 4D, 5D and 6D cases (D is the pile diameter). It is found that the pile spacing has some influence on the extent of soil liquefaction between piles. The vertical bearing capacity varies with liquefaction extent of inter-pile soil. The optimization of pile spacing varies with liquefaction extent. These results may provide some reference for the design of composite pile foundation under seismic loading.