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A visible-light-initiated C-H trifluoromethylation of quinoxalin-2(1H)-ones was established using a Z-scheme V2O5/g-C3N4 heterojunction as a recyclable photocatalyst in an inert atmosphere at room temperature under additive-free and mild conditions. A variety of trifluoromethylated quinoxalin-2-(1H)-one derivatives were heterogeneously generated in moderate to high yields, exhibiting good functional group tolerance. Remarkably, the recyclable V2O5/g-C3N4 catalyst could be reused five times with a slight loss of catalytic activity.
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A simple and practical electron donor-acceptor (EDA) strategy to synthesize various 3-alkylated coumarins from easily available coumarins and naturally abundant carboxylic acids under photocatalyst-, oxidant-, and additive-free and mild conditions is reported. Using Na2S as the catalytic electron donor, a series of primary, secondary, and tertiary carbon radicals can be efficiently generated, and the EDA complex can be regenerated without an alkaline additive.
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A 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene (4-CzIPN)-photocatalyzed cascade arylation/cyclization reaction of 2-isocyanobiaryls and iodonium ylides was established for the synthesis of 6-arylated phenanthridines. This is the first example of employing iodonium ylides as aryl radical sources in a visible-light-induced radical cascade cyclization reaction.
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Luz , Fenantridinas , CiclizaçãoRESUMO
The first example of the electrocatalytic multicomponent synthesis of 4-chloro/bromo/iodopyrazoles from hydrazines, acetylacetones and sodium halides under chemical oxidant- and external electrolyte-free conditions has been developed. Sodium halides played a dual role as a halogenation reagent and a supporting electrolyte. Mechanism studies revealed that the bromination reaction proceeded via an ionic pathway, whereas both chlorination and iodination proceeded via a radical pathway.
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Halogênios , Sódio , Halogenação , Oxidantes , ÍonsRESUMO
LncRNAs exert comprehensive effects in regulating the initiation and deterioration of hepatocellular carcinoma (HCC). However, the specific expression profiles and functional mechanisms of LINC00536 in HCC need to be disclosed. The study is intended to clarify the leverage of LINC00536 in HCC and investigate the potential mechanisms for the regulatory role of LINC00536 in the progression of HCC. In our study, LINC00536 was overexpressed in tumor samples of HCC patients and was related to poor prognosis. LINC00536 knockdown impaired cell viability, proliferation, migration, and invasion. LINC00536 can directly bind with miR-203b-5p, trimming the miR-203b-5p expression levels. VEGFA designates as a target of miR-203b-5p. Rescue research indicated that the miR-203b-5p inhibition or VEGFA overexpression could reverse the impaired cell phenotypes induced by LINC00536 knockdown. The in vivo experiments upheld the LINC00536/miR-203b-5p/VEGFA axis in HCC. Conclusively, LINC00536 could promote HCC deterioration via tuning the miR-203b-5p/VEGFA axis. This research may provide theoretical evidence for LINC00536 to get a gratifying therapeutic target for HCC.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , RNA Longo não Codificante , Carcinoma Hepatocelular/genética , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Fator A de Crescimento do Endotélio VascularRESUMO
The effects of small organic molecule (SOM) adsorption with benzene (C6H6), hexafluorobenzene (C6F6), and p-difluorobenzene (C6H4F2) on the electronic properties of stanene under external electric fields are investigated through first-principles calculations. Different adsorption sites and molecular orientations are considered to determine the most stable configurations of small organic molecule (SOM) adsorption on the surface of stanene. The results show that the internal electric field caused by the adsorption of small organic molecules destroys the symmetry of the two sublattices of stanene in C6H6/stanene, C6F6/stanene and C6H4F2/stanene systems with the most stable configurations, opening the band gaps of stanene with 39.5, 18.9 and 14.5 meV, respectively. Under an external electric field, a wide range of linearly tunable and sizable direct band gaps (31.6-420.1 meV for the C6H6/stanene system, 14.8-587.2 meV for the C6F6/stanene system and 14.5-490.2 meV for the C6H4F2/stanene system) are merely determined by the strength of the composite electric field despite its direction. The mechanism of charge transfer between stanene and organic molecules under an external electric field can be revealed using an equivalent capacitor model to explain the tunable charge transfer. More importantly, the high carrier mobility of the stable SOM/stanene systems under an external electric field is largely retained due to the weak interactions at the interface. These results indicate that the electronic properties of stanene can be effectively modulated by the surface adsorption of organic molecules under an external electric field, providing effective and reversible routes to enhance the performance of stanene for novel electronic devices in the future.
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Enterocytozoon bieneusi is a zoonotic parasite which is considered to be an opportunistic pathogen of humans and animals. A number of studies have reported E. bieneusi infection in various animals. However, no information is available on the occurrence of E. bieneusi in Tan sheep, a unique indigenous sheep species in the Ningxia Hui Autonomous Region, China. The objectives of the present study were to examine the prevalence and identify the genotypes of E. bieneusi in Tan sheep in China. A total of 1014 fecal specimens of Tan sheep from six farms in the Ningxia Hui Autonomous Region were examined by nested PCR amplification of the internal transcribed spacer (ITS) of nuclear ribosomal DNA. The total prevalence of E. bieneusi was 12.2% (124/1014), ranging from 0.5 to 22.2% on six farms. Sequence analysis identified 10 genotypes of E. bieneusi, including three known genotypes, BEB6, COS-I, and CHG13, and seven novel genotypes designated as NX1 to NX7, which all belonged to group 2 by phylogenetic analysis. This is the first report describing the prevalence of E. bieneusi in Tan sheep, and the new genotypes identified in the current study expand the genotype distribution of E. bieneusi. These findings provide baseline data and have implications for the epidemiology and control of E. bieneusi infection in Tan sheep.
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Enterocytozoon/isolamento & purificação , Microsporidiose/veterinária , Doenças dos Ovinos/parasitologia , Animais , China/epidemiologia , Enterocytozoon/classificação , Enterocytozoon/genética , Genótipo , Microsporidiose/epidemiologia , Microsporidiose/parasitologia , Filogenia , Prevalência , Ovinos , Doenças dos Ovinos/epidemiologiaRESUMO
Herein, the spin-forbidden cooling of a gallium hydride molecule is investigated using ab initio quantum chemistry. The cooling transition and the corresponding potential energy curves including , a3Π0-, a3Π0+, a3Π1, a3Π2, A1Π1, , 13Σ, , , and 23Σ states are simulated based on the multi-reference configuration interaction approach plus Davidson corrections method. By solving the nuclear Schrödinger equation, we calculate the spectroscopic constants of these states, which are in good agreement with the available experimental values. Based on the transition data, there seems to be a theoretical puzzle: highly diagonally distributed Franck-Condon factor f00 for transitions , , and for the gallium hydride molecule but the intervening state A1Π1 for transition is prohibitive to laser cooling. In addition, the transition does not have a suitable rate of optical cycling owing to a large radiative lifetime for state. Our theoretical simulation indicates the solution to the puzzle: the transition has a high emission rate, and there is a suitable radiative lifetime for a3Π1 state, which can ensure rapid and efficient laser cooling of gallium hydride. The proposed laser drives transition by using three wavelengths (main pump laser λ00; two repumping lasers λ10 and λ21). These results demonstrate the possibility of laser-cooling the gallium hydride molecule, and a sub-microkelvin cool temperature can be reached for this molecule.
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BACKGROUND: Eimeria tenella is an obligate intracellular parasitic protozoan that invades the chicken cecum and causes coccidiosis, which induces acute lesions and weight loss. Elucidating the anticoccidial mechanism of action of green tea polyphenols could aid the development of anticoccidial drugs and resolve the problem of drug resistance in E. tenella. METHODS: We constructed a model of E. tenella infection in Wuliangshan black-boned chickens, an indigenous breed of Yunnan Province, China, to study the efficacy of green tea polyphenols against the infection. Alterations in gene expression and in the microbial flora in the cecum were analyzed by ribonucleic acid (RNA) sequencing and 16S ribosomal RNA (rRNA) sequencing. Quantitative real-time polymerase chain reaction was used to verify the host gene expression data obtained by RNA sequencing. Network pharmacology and molecular docking were used to clarify the interactions between the component green tea polyphenols and the targeted proteins; potential anticoccidial herbs were also analyzed. RESULTS: Treatment with the green tea polyphenols led to a reduction in the lesion score and weight loss of the chickens induced by E. tenella infection. The expression of matrix metalloproteinase 7 (MMP7), MMP1, nitric oxide synthase 2 and ephrin type-A receptor 2 was significantly altered in the E. tenella infection plus green tea polyphenol-treated group and in the E. tenella infection group compared with the control group; these genes were also predicted targets of tea polyphenols. Furthermore, the tea polyphenol (-)-epigallocatechin gallate acted on most of the targets, and the molecular docking analysis showed that it has good affinity with interferon induced with helicase C domain 1 protein. 16S ribosomal RNA sequencing showed that the green tea polyphenols had a regulatory effect on changes in the fecal microbiota induced by E. tenella infection. In total, 171 herbs were predicted to act on two or three targets in MMP7, MMP1, nitric oxide synthase 2 and ephrin type-A receptor 2. CONCLUSIONS: Green tea polyphenols can directly or indirectly regulate host gene expression and alter the growth of microbiota. The results presented here shed light on the mechanism of action of green tea polyphenols against E. tenella infection in chickens, and have implications for the development of novel anticoccidial products.
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Produtos Biológicos , Eimeria tenella , Animais , Transcriptoma , Galinhas , RNA Ribossômico 16S/genética , Eimeria tenella/genética , Metaloproteinase 1 da Matriz , Metaloproteinase 7 da Matriz , Simulação de Acoplamento Molecular , Farmacologia em Rede , China , Antioxidantes , Óxido Nítrico Sintase , EfrinasRESUMO
Enterocytozoon bieneusi is a fungus-like protist parasite that can cause diarrhea and enteric diseases. The infection of E. bieneusi has been reported in many host species, including cattle and humans. However, information on prevalence and genotype distribution of E. bieneusi in dairy cattle in Yunnan province in China is still absent. In this study, 490 Holstein Cows and 351 dairy buffalo fecal samples were collected from three regions in Yunnan province, China. By using nest-PCR that targets the internal transcribed spacer (ITS), we found that the prevalence of E. bieneusi was 0.59% (5/841). DNA sequence analysis showed that five E. bieneusi genotypes were identified in this study, including two novel genotypes, YNDCEB-90 and YNDCEB-174, and three known genotypes (I, J, BEB4). Phylogenetic analysis revealed that two novel genotypes, YNDCEB-90 and YNDCEB-174, were clustered into Group 1, representing the zoonotic potential. The remaining genotypes I, J, and BEB4, which are the most frequent genotypes of E. bieneusi infection in cattle and lead to E. bieneusi infection in humans, belonged to Group 2. Although the lower prevalence of E. bieneusi was detected in dairy cattle in Yunnan province, it indicates that dairy cattle should be considered to be one of the potential hosts for transmitting E. bieneusi to humans. These findings are important for the development of effective prevention strategies for microsporidiosis.
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The objective of the present study was to determine the characterization of Toxoplasma gondii in cats, rats, and chickens in the border areas of Yunnan Province. A total of 259 samples was collected from 10 border areas in Yunnan Province including 94 cats, 58 rats, and 107 chickens. Samples were screened by a nested polymerase chain reaction (PCR) assay and the positive products were analyzed by multilocus PCR-restriction fragment length polymorphism (RFLP) to determine the genotypes. Toxoplasma gondii deoxyribonucleic acid (DNA) was detected from 15.96% of 94 cats, 15.52% of 58 rats, and 6.54% of 107 chickens, respectively, and the average infection rate is 11.97%. Using the multilocus PCR-RFLP, we found that the genotype of T. gondii in cats and rats was ToxoDB#9. Because of low DNA concentration, no genotype was determined from chickens. These results fill the gaps of knowledge in the prevalence and genotype of T. gondii in the border areas of Yunnan Province and have implications for the better control of T. gondii infection in humans and animals.
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Doenças do Gato/epidemiologia , Galinhas/parasitologia , Doenças das Aves Domésticas/epidemiologia , Ratos/parasitologia , Doenças dos Roedores/epidemiologia , Toxoplasmose Animal/epidemiologia , Animais , Encéfalo/parasitologia , Doenças do Gato/parasitologia , Gatos , China/epidemiologia , DNA de Protozoário/química , DNA de Protozoário/isolamento & purificação , Marcadores Genéticos , Técnicas de Genotipagem/veterinária , Tipagem de Sequências Multilocus/veterinária , Reação em Cadeia da Polimerase/veterinária , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Prevalência , Doenças dos Roedores/parasitologia , Toxoplasma/classificação , Toxoplasma/genética , Toxoplasmose Animal/parasitologiaRESUMO
Giardia duodenalis is a common intestinal protozoa, which can cause the occurrence of diarrhea, weight loss, and even death in animals or human, this threatens the husbandry industry and public health. It can infect virtually humans and all domestic animals including sheep. Tan sheep is one of the most important sheep breeds, which is short-tailed indigenous sheep breed used for production of high quality meat and pelts in China. However, there are no report regarding the occurrence and multilocus genotyping of G. duodenalis in Tan sheep in northwestern China. Thus, the objective of the present study was to investigate the prevalence and multilocus genotypes of G. duodenalis in Tan sheep. 1014 fecal samples were collected from Tan sheep from Ningxia Hui Autonomous Region, and three loci (ß-giardin (bg), glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi) genes) were amplified by nested PCR. The prevalence of G. duodenalis in Tan sheep was 14.5% (147/1014), two assemblages (assemblage A, n = 43; and E, n = 90) were detected, including one novel assemblage A at bg locus, one novel assemblage A at tpi locus, and 10 and 11 novel subtypes of assemblage E were detected at the bg and gdh loci, respectively. One MLGs was formed based on sequence variation among the three loci. Moreover, 9 Tan sheep were infected with two assemblages (A and E) based on the three loci. These findings expand the host range of G. duodenalis and revealed genetic diversity of G. duodenalis assemblages in Tan sheep.
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Técnicas de Genotipagem , Giardia lamblia/classificação , Giardíase/veterinária , Tipagem de Sequências Multilocus , Carneiro Doméstico/parasitologia , Fatores Etários , Animais , China/epidemiologia , Fazendas , Fezes/parasitologia , Feminino , Genótipo , Giardíase/epidemiologia , Especificidade de Hospedeiro , Masculino , Filogenia , Prevalência , Proteínas de Protozoários/genética , Análise de Sequência de DNA , Carneiro Doméstico/classificaçãoRESUMO
Enterocytozoon bieneusi and Giardia duodenalis are important opportunistic enteric zoonotic pathogens that cause diarrhoea and intestinal diseases in animals and humans. China is the largest producer of pigs, but whether Tibetan pigs, a unique pig breed in Tibet, are infected with E. bieneusi and G. duodenalis is unknown. Therefore, we conducted a molecular epidemiological survey to determine the prevalence of E. bieneusi and G. duodenalis in Tibetan pigs in Tibet, China, and identified the genotypes of these causative agents. A total of 345 faecal specimens were collected from Tibetan pigs from three Tibet counties (Milin, Cuona and Gongbujiangda), examined by nested PCR and sequenced utilizing genetic markers in the ribosomal internal transcribed spacer (ITS) region of the rRNA and glutamate dehydrogenase (gdh) gene for E. bieneusi and G. duodenalis, respectively. Moreover, using multilocus sequence typing, the subtypes of E. bieneusi were identified based on four loci (MS1, MS3, MS4 and MS7). A total of 41 (11.88%) faecal samples from Tibetan pigs were E. bieneusi-positive, and 2 (0.58%) were G. duodenalis-positive. The multivariate logistic regression analysis showed that age was considered a risk factor for Tibetan pig infection of E. bieneusi. Two novel (GB11, GB31) and four known E. bieneusi genotypes (EbpC, EbpD, PigEBITS5 and CHS12) were identified and were all classified as zoonotic group 1 according to the phylogenetic analysis. Two MLGs (MLGI and MLGII) were further identified in the E. bieneusi EbpC genotype by multilocus sequence typing analysis. In addition, two G. duodenalis assemblages (D and E) were found in the present study. To our knowledge, the current study is the first to detect the prevalence and perform genetic characterization of G. duodenalis in Tibetan pigs in Tibet, China. The results could provide essential data for controlling E. bieneusi and G. duodenalis infections in Tibetan pigs that are in contact with other animals and humans, as Tibetan pigs could be a potential source for human infection by these pathogens.
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Enterocytozoon/genética , Giardia lamblia/genética , Giardíase/veterinária , Microsporidiose/veterinária , Doenças dos Suínos/epidemiologia , Animais , Enterocytozoon/classificação , Fezes/microbiologia , Genótipo , Geografia Médica , Giardia lamblia/classificação , Tipagem de Sequências Multilocus , Filogenia , Prevalência , Vigilância em Saúde Pública , Análise de Sequência de DNA , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/parasitologia , Tibet/epidemiologiaRESUMO
To gain insights into differences in the virulence among T. gondii strains at the post-translational level, we conducted a quantitative analysis of the phosphoproteome profile of T. gondii strains belonging to three different genotypes. Phosphopeptides from three strains, type I (RH strain), type II (PRU strain) and ToxoDB#9 (PYS strain), were enriched by titanium dioxide (TiO2) affinity chromatography and quantified using iTRAQ technology. A total of 1,441 phosphopeptides, 1,250 phosphorylation sites and 759 phosphoproteins were detected. In addition, 392, 298, and 436 differentially expressed phosphoproteins (DEPs) were identified in RH strain when comparing RH/PRU strains, in PRU strain when comparing PRU/PYS strains, and in PYS strain when comparing PYS/RH strains, respectively. Functional characterization of the DEPs using GO, KEGG, and STRING analyses revealed marked differences between the three strains. In silico kinase substrate motif analysis of the DEPs revealed three (RxxS, SxxE, and SxxxE), three (RxxS, SxxE, and SP), and five (SxxE, SP, SxE, LxRxxS, and RxxS) motifs in RH strain when comparing RH/PRU strains, in PRU strain when comparing PRU/PYS, and in PYS strain when comparing PYS/RH strains, respectively. This suggests that multiple overrepresented protein kinases including PKA, PKG, CKII, IKK, and MAPK could be involved in such a difference between T. gondii strains. Kinase associated network analysis showed that ROP5, ROP16, and cell-cycle-associated protein kinase CDK were the most connected kinase peptides. Our data reveal significant changes in the abundance of phosphoproteins between T. gondii genotypes, which explain some of the mechanisms that contribute to the virulence heterogeneity of this parasite.