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1.
J Am Chem Soc ; 146(10): 6936-6946, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38414423

RESUMEN

Here, we describe a cooperative Pd(0)/chiral phosphoric acid catalytic system that allows us to realize the first chemo-, regio-, and enantioselective sequential cross-[4 + 2]-cycloaddition/decarboxylation reaction between 2-pyrones and unactivated acyclic 1,3-dienes. The key to the success of this transformation is the utilization of an achiral N-heterocyclic carbene (NHC) as the ligand and a newly developed chiral phosphoric acid as the cocatalyst. Experimental investigations and computational studies support the idea that the Pd(0)/NHC complex acts as a π-Lewis base to increase the nucleophilicity of 1,3-dienes via η2 coordination, while the chiral phosphoric acid simultaneously increases the electrophilicity of 2-pyrones by hydrogen bonding. By this synergistic catalysis, the sequential cross-[4 + 2]-cycloaddition and decarboxylation reaction proceeds efficiently, enabling the preparation of a wide range of chiral vinyl-substituted 1,3-cyclohexadienes in good yields and enantioselectivities. The synthetic utility of this reaction is demonstrated by synthetic transformations of the product to various valuable chiral six-membered carbocycles.

2.
BMC Microbiol ; 24(1): 206, 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38858614

RESUMEN

OBJECTIVE: This study aims to examine the impact of PE/PPE gene mutations on the transmission of Mycobacterium tuberculosis (M. tuberculosis) in China. METHODS: We collected the whole genome sequencing (WGS) data of 3202 M. tuberculosis isolates in China from 2007 to 2018 and investigated the clustering of strains from different lineages. To evaluate the potential role of PE/PPE gene mutations in the dissemination of the pathogen, we employed homoplastic analysis to detect homoplastic single nucleotide polymorphisms (SNPs) within these gene regions. Subsequently, logistic regression analysis was conducted to analyze the statistical association. RESULTS: Based on nationwide M. tuberculosis WGS data, it has been observed that the majority of the M. tuberculosis burden in China is caused by lineage 2 strains, followed by lineage 4. Lineage 2 exhibited a higher number of transmission clusters, totaling 446 clusters, of which 77 were cross-regional clusters. Conversely, there were only 52 transmission clusters in lineage 4, of which 9 were cross-regional clusters. In the analysis of lineage 2 isolates, regression results showed that 4 specific gene mutations, PE4 (position 190,394; c.46G > A), PE_PGRS10 (839,194; c.744 A > G), PE16 (1,607,005; c.620T > G) and PE_PGRS44 (2,921,883; c.333 C > A), were significantly associated with the transmission of M. tuberculosis. Mutations of PE_PGRS10 (839,334; c.884 A > G), PE_PGRS11 (847,613; c.1455G > C), PE_PGRS47 (3,054,724; c.811 A > G) and PPE66 (4,189,930; c.303G > C) exhibited significant associations with the cross-regional clusters. A total of 13 mutation positions showed a positive correlation with clustering size, indicating a positive association. For lineage 4 strains, no mutations were found to enhance transmission, but 2 mutation sites were identified as risk factors for cross-regional clusters. These included PE_PGRS4 (338,100; c.974 A > G) and PPE13 (976,897; c.1307 A > C). CONCLUSION: Our results indicate that some PE/PPE gene mutations can increase the risk of M. tuberculosis transmission, which might provide a basis for controlling the spread of tuberculosis.


Asunto(s)
Mutación , Mycobacterium tuberculosis , Polimorfismo de Nucleótido Simple , Tuberculosis , Secuenciación Completa del Genoma , Mycobacterium tuberculosis/genética , Mycobacterium tuberculosis/clasificación , Mycobacterium tuberculosis/aislamiento & purificación , China/epidemiología , Humanos , Tuberculosis/transmisión , Tuberculosis/microbiología , Tuberculosis/epidemiología , Genoma Bacteriano , Femenino , Masculino , Proteínas Bacterianas/genética , Adulto
3.
Angew Chem Int Ed Engl ; 62(32): e202303876, 2023 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-37286494

RESUMEN

Herein, we show that the combination of the Birch reduction of readily available anisole derivatives and the catalytic asymmetric inverse-electron-demand Diels-Alder reaction of 2-pyrones can serve as a powerful platform for the diverse synthesis of synthetically important cis-decalin scaffolds. Enabled by a well-modified chiral bis(oxazoline) ligand/CuII complex, a wide range of polysubstituted cis-decalin scaffolds with up to six contiguous stereocenters were generated efficiently. The synthetic potential of this method is demonstrated by the concise synthesis of the sesquiterpene (+)-occidentalol and a key intermediate for seven triterpenes. Mechanistic studies suggest the 1,3-cyclohexadienes formed in situ are the key intermediates, and efficient kinetic resolution occurs when C2- and/or C3-substituted 1,4-cyclohexadienes are utilized as substrates. DFT calculations elucidated that the Diels-Alder reaction proceeds in a stepwise fashion and revealed the origins of the stereoselectivities.

4.
J Am Chem Soc ; 144(50): 22858-22864, 2022 12 21.
Artículo en Inglés | MEDLINE | ID: mdl-36480794

RESUMEN

We report herein an efficient approach for the enantioselective synthesis of inherently chiral calix[4]arenes via palladium-catalyzed asymmetric intramolecular C-H arylations. Using a chiral bifunctional phosphine-carboxylate ligand, the inherent chirality on macrocyclic scaffolds was induced successfully, from which a wide range of calix[4]arenes with fluorenone motifs were obtained with good yields and excellent enantioselectivities (up to >99% ee). The synthetic utility of this method was demonstrated by diverse transformations of the products, thus substantially expanding the chemical space of chiral calix[4]arenes. Further investigations of photophysical and chiroptical properties revealed that calix[4]arenes bearing two fluorenone moieties displayed remarkable glum values (up to 0.019), highlighting the great potential of inherent chirality in the development of organic optoelectronic materials.


Asunto(s)
Gastrópodos , Poríferos , Animales , Paladio , Estereoisomerismo , Ácidos Carboxílicos , Flores , Catálisis
5.
J Am Chem Soc ; 143(24): 8993-9001, 2021 06 23.
Artículo en Inglés | MEDLINE | ID: mdl-34106720

RESUMEN

The enantioselective synthesis of axially chiral biaryls by a copper-catalyzed Diels-Alder/retro-Diels-Alder reaction of 2-pyrones with alkynes is reported herein. Using electron-deficient 2-pyrones and electron-rich 1-naphthyl acetylenes as the reaction partners, a broad range of axially chiral biaryl esters are obtained in excellent yields (up to 97% yield) and enantioselectivities (up to >99% ee). DFT calculations reveal the reaction mechanism and provide insights into the origins of the stereoselectivities. The practicality and robustness of this reaction are showcased by gram-scale synthesis. The synthetic utilizations are demonstrated by the amenable transformations of the products.

6.
Org Biomol Chem ; 18(20): 3832-3837, 2020 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-32396933

RESUMEN

An environmentally benign electrochemically enabled site-selective functionalization of indole or aniline derivatives with hexafluoroisopropanol in the presence of tetrabutyl ammonium hexafluorophosphate as the redox catalyst and electrolyte was demonstrated in this work. Under mild electro-oxidation conditions, a series of hexafluoroisopropoxy indole and aniline derivatives with pharmacological activity were obtained. This conversion does not need transition metals and oxidants, and has good functional group tolerance. The in vitro cytotoxicity of all compounds was evaluated by the MTT assay against four human cancer cell lines. The results revealed that hexafluoroisopropoxy indoles have good antitumor activity and compound 2i increased the intracellular levels of ROS and inhibited apoptosis in HeLa cells.

7.
Am J Physiol Cell Physiol ; 317(2): C253-C261, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-30649914

RESUMEN

Myocardial ischemia-reperfusion (I/R) is a common and lethal disease that threatens people's life worldwide. The underlying mechanisms are under intensive study and yet remain unclear. Here, we explored the function of miR-322/503 in myocardial I/R injury. We used isolated rat perfused heart as an in vivo model and H9c2 cells subjected with the oxygen and glucose deprivation followed by reperfusion as in vitro model to study myocardial I/R injury. 2,3,5-Triphenyltetrazolium chloride (TTC) staining was used to measure the infarct size, and terminal deoxynucleotidyl transferase dUTP-mediated nick-end label (TUNEL) staining was used to examine apoptosis. Quantitative RT-PCR and Western blot were used to determine expression levels of miR-322/503, Smad ubiquitin regulatory factor 2 (Smurf2), enhancer of zeste homolog 2 (EZH2), p-Akt, and p-GSK3ß. Overexpression of miR-322/503 decreased infarct size, inhibited cell apoptosis, and promoted cell proliferation through upregualtion of p-Akt and p-GSK3ß. Thus the expression of miR-322/503 was reduced during I/R process. On the molecular level, miR-322/503 directly bound Smurf2 mRNA and suppressed its translation. Smurf2 ubiquitinated EZH2 and degraded EZH2, which could activate Akt/GSK3ß signaling. Our study demonstrates that miR-322/503 plays a beneficial role in myocardial I/R injury. By inhibition of Smurf2 translation, miR-322/503 induces EZH2 expression and activates Akt/GSK3ß pathway, thereby protecting cells from ischemia reperfusion injury.


Asunto(s)
Proteína Potenciadora del Homólogo Zeste 2/metabolismo , Glucógeno Sintasa Quinasa 3 beta/metabolismo , MicroARNs/metabolismo , Infarto del Miocardio/prevención & control , Daño por Reperfusión Miocárdica/prevención & control , Miocitos Cardíacos/enzimología , Proteínas Proto-Oncogénicas c-akt/metabolismo , Ubiquitina-Proteína Ligasas/metabolismo , Animales , Apoptosis , Sitios de Unión , Hipoxia de la Célula , Línea Celular , Proliferación Celular , Modelos Animales de Enfermedad , Glucosa/deficiencia , Preparación de Corazón Aislado , Masculino , MicroARNs/genética , Infarto del Miocardio/enzimología , Infarto del Miocardio/genética , Infarto del Miocardio/patología , Daño por Reperfusión Miocárdica/enzimología , Daño por Reperfusión Miocárdica/genética , Daño por Reperfusión Miocárdica/patología , Miocitos Cardíacos/patología , Fosforilación , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas Sprague-Dawley , Transducción de Señal , Ubiquitina-Proteína Ligasas/genética
8.
J Sep Sci ; 41(15): 3060-3068, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29878532

RESUMEN

Thermo-responsive magnetic molecularly imprinted polymers were prepared by simple surface molecular imprinting polymerization for the selective adsorption and enrichment of formononetin from Trifolium pretense by temperature regulation. Using formononetin as a template, N-isopropylacrylamide as the thermo-responsive functional monomer, and methacrylic acid as an assisting functional monomer, the polymers were synthesized on the surface of the magnetic substrate. The results show that imprinted polymers attained controlled adsorption of formononetin in response to the temperature change, with large adsorption capacity (16.43 mg/g), fast kinetics (60 min) and good selectivity at 35°C compared with that at 25 and 45°C. The selectivity experiment indicated that the materials had excellent recognition ability for formononetin and the selectivity factors were between 1.32 and 2.98 towards genistein and daidzein. The excellent linearity was attained in the range of 5-100 µg/mL, with low detection limits and low quantitation limits of 0.017 and 0.063 µg/mL, respectively. Furthermore, the thermo-responsive magnetic molecularly imprinted polymers were successfully utilized for enriching and purifying formononetin from Trifolium pretense. The analytical results indicate that the imprinted polymers are promising materials for selective identification and enrichment of formononetin in complicated herbal medicines by simple temperature-responsive regulation.


Asunto(s)
Isoflavonas/química , Impresión Molecular , Polímeros/química , Temperatura , Adsorción , Isoflavonas/aislamiento & purificación , Fenómenos Magnéticos , Polimerizacion , Polímeros/síntesis química , Propiedades de Superficie , Trifolium/química
9.
Cell Physiol Biochem ; 43(6): 2226-2241, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29069652

RESUMEN

BACKGROUND/AIMS: The study aimed to investigate the protective effect of curcumin against oxidative stress-induced injury of Parkinson's disease (PD) through the Wnt/ß-catenin signaling pathway in rats. METHODS: The successfully established PD rat models and normal healthy rats were randomly assigned into the 6-hydroxydopamine (6-OHDA), the curcumin (Cur) and the control groups. Immunohistochemistry was used to detect the positive expression of tyrosine hydroxylase (TH), dopamine transporter (DAT) and glial fibrillary acidic protein (GFAP). Deutocerebrum primary cells were extracted and classified into the control, 6-OHDA, Cur (5, 10, 15 µmol/L), Dickkopf-1 (DKK-1) and Cur + DKK-1 groups. MTT assays, adhesion tests and TUNEL staining were used to assess cell viability, adhesion and apoptosis, respectively. Western blotting and qRT-PCR were used to examine the protein and mRNA expressions of Wnt3a and ß-catenin and the c-myc and cyclinD1 mRNA expressions. RESULTS: TH and DAT expressions in the Cur group were elevated and GFAP was reduced compared with the 6-OHDA group. Curcumin enhanced viability, survival and adhesion and attenuated apoptosis of deutocerebrum primary cells by activating the Wnt/ß-catenin signaling pathway. Higher Wnt3a and ß-catenin mRNA and protein expressions and c-myc and cyclinD1 mRNA expressions, enhanced superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) contents, decreased malondialdehyde (MDA) content and elevated mitochondrial membrane potential (∆ψm) were found in the 10 and 15 µmol/L Cur groups compared with the 6-OHDA group. However, opposite tendencies were found in the Cur + DKK-1 group compared to the 10 µmol/L Cur group. CONCLUSION: This study suggests that curcumin could protect against oxidative stress-induced injury in PD rats via the Wnt/ß-catenin signaling pathway.


Asunto(s)
Curcumina/farmacología , Estrés Oxidativo/efectos de los fármacos , Sustancias Protectoras/farmacología , Vía de Señalización Wnt/efectos de los fármacos , Animales , Apoptosis/efectos de los fármacos , Astrocitos/citología , Astrocitos/efectos de los fármacos , Astrocitos/metabolismo , Conducta Animal/efectos de los fármacos , Adhesión Celular/efectos de los fármacos , Células Cultivadas , Ciclina D1/genética , Ciclina D1/metabolismo , Modelos Animales de Enfermedad , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/genética , Proteínas de Transporte de Dopamina a través de la Membrana Plasmática/metabolismo , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/metabolismo , Glutatión Peroxidasa/metabolismo , Inmunohistoquímica , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Masculino , Malondialdehído/metabolismo , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Oxidopamina/farmacología , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/veterinaria , Proteínas Proto-Oncogénicas c-myc/genética , Proteínas Proto-Oncogénicas c-myc/metabolismo , Ratas , Ratas Sprague-Dawley , Superóxido Dismutasa/metabolismo , Tirosina 3-Monooxigenasa/genética , Tirosina 3-Monooxigenasa/metabolismo , Proteína Wnt3/genética , Proteína Wnt3/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
10.
Biomed Chromatogr ; 31(5)2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27761923

RESUMEN

Pulsatilla chinensis (Bunge) Regel is commonly used in Asia, and anemoside B4 (AB4) is its major saponin, with diverse pharmaceutical effects. Previous studies showed that intestinal flora plays an important role in the metabolism of herbs administered orally. In this study, the metabolic profile of AB4 with microflora in rat small and large intestines in vitro was investigated. Gut microflora was collected from different intestinal segments and anaerobically incubated with AB4 at 37°C for 24, 48, 72 and 96 h, respectively. A total of 10 metabolites were detected and identified by ultra- performance liquid chromatography/quadrupole time-of-flight mass spectrometry, involving the products of oxygenation and deglycosylation reactions. Gut microflora in the large intestine generated more comprehensive metabolic pathways, which appears to be attributable to the wider range of bacterial types and numbers of bacteria. Human cancer cell lines SMMC-7721, Hela and MCF-7 were treated with metabolite pools by MTT assay, together with M6 as the greatest deglycosylation product. As a result, M6 exhibited a reduction in cell viability of SMMC-7721 with an IC50 value of 22.28 ± 1.26 µg/mL. The present study provided scientific evidence for AB4 metabolism in small and large intestines, which is helpful to reveal the active forms of AB4 in vivo.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Intestino Grueso/microbiología , Intestino Delgado/microbiología , Saponinas/farmacocinética , Espectrometría de Masas en Tándem/métodos , Animales , Biotransformación , Línea Celular , Proliferación Celular/efectos de los fármacos , Microbioma Gastrointestinal , Humanos , Intestino Grueso/efectos de los fármacos , Intestino Grueso/metabolismo , Intestino Delgado/efectos de los fármacos , Intestino Delgado/metabolismo , Masculino , Estructura Molecular , Ratas Sprague-Dawley , Saponinas/química , Saponinas/metabolismo , Saponinas/farmacología
11.
J Virol ; 89(20): 10532-47, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26269185

RESUMEN

UNLABELLED: Despite the identification of horseshoe bats as the reservoir of severe acute respiratory syndrome (SARS)-related coronaviruses (SARSr-CoVs), the origin of SARS-CoV ORF8, which contains the 29-nucleotide signature deletion among human strains, remains obscure. Although two SARS-related Rhinolophus sinicus bat CoVs (SARSr-Rs-BatCoVs) previously detected in Chinese horseshoe bats (Rhinolophus sinicus) in Yunnan, RsSHC014 and Rs3367, possessed 95% genome identities to human and civet SARSr-CoVs, their ORF8 protein exhibited only 32.2 to 33% amino acid identities to that of human/civet SARSr-CoVs. To elucidate the origin of SARS-CoV ORF8, we sampled 348 bats of various species in Yunnan, among which diverse alphacoronaviruses and betacoronaviruses, including potentially novel CoVs, were identified, with some showing potential interspecies transmission. The genomes of two betacoronaviruses, SARSr-Rf-BatCoV YNLF_31C and YNLF_34C, from greater horseshoe bats (Rhinolophus ferrumequinum), possessed 93% nucleotide identities to human/civet SARSr-CoV genomes. Although these two betacoronaviruses displayed lower similarities than SARSr-Rs-BatCoV RsSHC014 and Rs3367 in S protein to civet SARSr-CoVs, their ORF8 proteins demonstrated exceptionally high (80.4 to 81.3%) amino acid identities to that of human/civet SARSr-CoVs, compared to SARSr-BatCoVs from other horseshoe bats (23.2 to 37.3%). Potential recombination events were identified around ORF8 between SARSr-Rf-BatCoVs and SARSr-Rs-BatCoVs, leading to the generation of civet SARSr-CoVs. The expression of ORF8 subgenomic mRNA suggested that the ORF8 protein may be functional in SARSr-Rf-BatCoVs. The high Ka/Ks ratio among human SARS-CoVs compared to that among SARSr-BatCoVs supported that ORF8 is under strong positive selection during animal-to-human transmission. Molecular clock analysis using ORF1ab showed that SARSr-Rf-BatCoV YNLF_31C and YNLF_34C diverged from civet/human SARSr-CoVs in approximately 1990. SARS-CoV ORF8 originated from SARSr-CoVs of greater horseshoe bats through recombination, which may be important for animal-to-human transmission. IMPORTANCE: Although horseshoe bats are the primary reservoir of SARS-related coronaviruses (SARSr-CoVs), it is still unclear how these bat viruses have evolved to cross the species barrier to infect civets and humans. Most human SARS-CoV epidemic strains contain a signature 29-nucleotide deletion in ORF8, compared to civet SARSr-CoVs, suggesting that ORF8 may be important for interspecies transmission. However, the origin of SARS-CoV ORF8 remains obscure. In particular, SARSr-Rs-BatCoVs from Chinese horseshoe bats (Rhinolophus sinicus) exhibited <40% amino acid identities to human/civet SARS-CoV in the ORF8 protein. We detected diverse alphacoronaviruses and betacoronaviruses among various bat species in Yunnan, China, including two SARSr-Rf-BatCoVs from greater horseshoe bats that possessed ORF8 proteins with exceptionally high amino acid identities to that of human/civet SARSr-CoVs. We demonstrated recombination events around ORF8 between SARSr-Rf-BatCoVs and SARSr-Rs-BatCoVs, leading to the generation of civet SARSr-CoVs. Our findings offer insight into the evolutionary origin of SARS-CoV ORF8 protein, which was likely acquired from SARSr-CoVs of greater horseshoe bats through recombination.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Genoma Viral , ARN Viral/genética , Recombinación Genética , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/genética , Proteínas de la Matriz Viral/genética , Secuencia de Aminoácidos , Animales , Secuencia de Bases , China , Quirópteros/virología , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/transmisión , Infecciones por Coronavirus/virología , Evolución Molecular , Expresión Génica , Humanos , Datos de Secuencia Molecular , Filogenia , Filogeografía , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Viral/metabolismo , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/clasificación , Coronavirus Relacionado al Síndrome Respiratorio Agudo Severo/metabolismo , Alineación de Secuencia , Homología de Secuencia de Ácido Nucleico , Síndrome Respiratorio Agudo Grave/genética , Síndrome Respiratorio Agudo Grave/metabolismo , Síndrome Respiratorio Agudo Grave/transmisión , Síndrome Respiratorio Agudo Grave/virología , Proteínas de la Matriz Viral/metabolismo , Viverridae/virología
12.
Emerg Infect Dis ; 20(9): 1433-42, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25144604

RESUMEN

Yunnan Province in China borders 3 countries (Vietnam, Laos, and Myanmar) in Southeast Asia. In the 1980s, a large-scale rabies epidemic occurred in this province, which subsided by the late 1990s. However, 3 human cases of rabies in 2000 indicated reemergence of the disease in 1 county. In 2012, rabies was detected in 77 counties; 663 persons died of rabies during this new epidemic. Fifty two rabies virus strains obtained during 2008-2012 were identified and analyzed phylogenetically by sequencing the nucleoprotein gene. Of the 4 clades identified, clades YN-A and YN-C were closely related to strains from neighboring provinces, and clade YN-B was closely related to strains from Southeast Asia, but formed a distinct branch. Rabies virus diversity might be attributed to dog movements among counties, provinces, and neighboring countries. These findings suggest that Yunnan Province is a focal point for spread of rabies between Southeast Asia and China.


Asunto(s)
Enfermedades Transmisibles Emergentes/epidemiología , Virus de la Rabia/genética , Rabia/epidemiología , Animales , Antígenos Virales/inmunología , Asia Sudoriental/epidemiología , China/epidemiología , Enfermedades de los Perros/virología , Perros , Femenino , Genes Virales , Variación Genética , Geografía Médica , Humanos , Masculino , Datos de Secuencia Molecular , Filogenia , Rabia/virología , Virus de la Rabia/clasificación , Virus de la Rabia/inmunología , Estaciones del Año , Vigilancia de Guardia , Análisis de Secuencia de ADN , Análisis Espacial
13.
Environ Sci Pollut Res Int ; 31(18): 27240-27258, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38509309

RESUMEN

Growing evidence has found the health protective effects of greenness exposure on tuberculosis (TB) and the impact of ambient air pollutants on TB drug-resistance. However, it remains unclear whether residential greenness is also beneficial to reduce TB drug-resistance, and whether air pollution modify the greenness-TB resistance relationship. We enrolled 5006 newly-diagnosed TB patients from Shandong, China, during 2014 to 2021. Normalized Difference Vegetation Index (NDVI) in 250 m and 500 m buffer around individuals' residential zone was used to assess greenness exposure. All patients were divided by quartiles of NDVI250-m and NDVI500-m (from low to high: Q1, Q2, Q3, Q4) respectively. Six logistic regression models (NDVI, NDVI + PM2.5/PM10/SO2/NO2/O3) were used to estimate the association of NDVI and TB drug-resistance when adjusting different air pollutants or not. All models were adjusted for age, gender, body mass index, complications, smoking, drinking, population density, nighttime light index, road density. Compared with participants in NDVI250-m Q1 and NDVI500-m Q1, other groups had lower rates of MDR-TB, PDR-TB, RFP-resistance, SM-resistance, RFP + SM resistance, INH + RFP + EMB + SM resistance. NDVI500-m reduced the risk of multidrug resistant tuberculosis (MDR-TB) and the adjusted odds ratio (aOR, 95% confidence interval, CI) compared with NDVI500-m Q1 were 0.736 (0.547-0.991) in NDVI + PM10 model, 0.733 (0.544-0.986) in NDVI + PM2.5 model, 0.735(0.546-0.99) in NDVI + SO2 model, 0.736 (0.546-0.991) in NDVI + NO2 model, respectively, P < 0.05. NDVI500-m contributed to a decreased risk of streptomycin (SM)-resistance. The aOR of rifampicin (RFP) + SM resistance were 0.132 (NDVI250-m, Q4 vs Q1, 95% CI: 0.03-0.578), 0.199 (NDVI500-m, Q3 vs. Q1, 95% CI: 0.057-0.688) and 0.264 (NDVI500-m, Q4 vs. Q1, 95% CI: 0.087-0.799). The adjusted ORs (Q2 vs. Q1, 95% CI) of isoniazid (INH) + RFP + ethambutol (EMB) + SM resistance in 500 m buffer were 0.276 (0.119-0.639) in NDVI model, 0.279 (0.11-0.705) in NDVI + PM10 model, 0.281 (0.111-0.713) in NDVI + PM2.5 model, 0.279 (0.11-0.709) in NDVI + SO2 model, 0.296 (0.117-0.754) in NDVI + NO2 model, 0.294 (0.116-0.748) in NDVI + O3 model, respectively. The study showed, for the first time, that residential greenness exposure in 500 m buffer is beneficial for reducing newly-diagnosed DR-TB (including PDR-RB, MDR-TB, MR-TB), and ambient air pollutants may partially mediate this association.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire , Exposición a Riesgos Ambientales , Tuberculosis Resistente a Múltiples Medicamentos , Humanos , China , Masculino , Femenino , Adulto , Persona de Mediana Edad
14.
Food Chem ; 424: 136133, 2023 Oct 30.
Artículo en Inglés | MEDLINE | ID: mdl-37267649

RESUMEN

Rapid detection of genistein in soya products has remained difficult. Current methods necessitate sample handling and use of costly instruments. Here, using a simple one-pot reverse microemulsion method, a sensor based on N-doped carbon dots conjugated molecularly imprinted polymers (N-CDs@MIPs) was synthesized to analyze genistein. N-doped carbon dots were used as fluorescent component, genistein as the template molecule, and molecularly imprinted polymers as the selective sorbent in this fluorescence sensor. The sensor was then examined and optical studies demonstrated that N-CDs@MIPs not only had strong fluorescence emission and outstanding optical stability, but also had good sensitivity (detection limit 35.7 nM) and selectivity to genistein. Furthermore, the N-CDs@MIPs materials were used to analyze genistein in soya products, and the findings (which ranged from 99.77% to 106.11%) show that the N-CDs@MIPs has high potential for quickly detecting the amount of genistein in complicated food samples.


Asunto(s)
Impresión Molecular , Puntos Cuánticos , Carbono , Polímeros Impresos Molecularmente , Genisteína , Impresión Molecular/métodos , Espectrometría de Fluorescencia/métodos , Polímeros , Límite de Detección , Colorantes Fluorescentes
15.
Front Genet ; 14: 1217255, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38259610

RESUMEN

Introduction: Tuberculosis (TB) is an infectious disease caused by a bacterium called Mycobacterium tuberculosis (Mtb). Previous studies have primarily focused on the transmissibility of multidrug-resistant (MDR) or extensively drug-resistant (XDR) Mtb. However, variations in virulence across Mtb lineages may also account for differences in transmissibility. In Mtb, polyketide synthase (PKS) genes encode large multifunctional proteins which have been shown to be major mycobacterial virulence factors. Therefore, this study aimed to identify the role of PKS mutations in TB transmission and assess its risk and characteristics. Methods: Whole genome sequences (WGSs) data from 3,204 Mtb isolates was collected from 2011 to 2019 in China. Whole genome single nucleotide polymorphism (SNP) profiles were used for phylogenetic tree analysis. Putative transmission clusters (≤10 SNPs) were identified. To identify the role of PKS mutations in TB transmission, we compared SNPs in the PKS gene region between "clustered isolates" and "non-clustered isolates" in different lineages. Results: Cluster-associated mutations in ppsA, pks12, and pks13 were identified among different lineage isolates. They were statistically significant among clustered strains, indicating that they may enhance the transmissibility of Mtb. Conclusion: Overall, this study provides new insights into the function of PKS and its localization in M. tuberculosis. The study found that ppsA, pks12, and pks13 may contribute to disease progression and higher transmission of certain strains. We also discussed the prospective use of mutant ppsA, pks12, and pks13 genes as drug targets.

16.
Abdom Imaging ; 37(5): 738-45, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22310902

RESUMEN

OBJECTIVES: To enhance diagnosis of gastrointestinal neuroendocrine carcinomas using CT and contrast-enhanced CT images. METHODS: A total of 44 patients with gastrointestinal neuroendocrine carcinomas, as confirmed by clinical pathology and immunohistochemistry in the Sixth Affiliated People's Hospital of Shanghai Jiao Tong University Shanghai China, were included in the study. CT and enhanced CT scanning were performed, and the resulting images were reviewed and analyzed. RESULTS: Twenty-seven males and 17 females were enrolled. Gastrointestinal involvement included the following: 5 cases located in the middle or inferior segment of the esophagus; 5 in the gastric cardia, 15 in the body of stomach, 6 located in the gastric antrum; 5 located in the Vater papilla of the duodenum; and 8 located in the colon. Among the 44 cases 80%-90% of the lesions had homogeneous density. Totally 81.8% (36/44) cases demonstrated homogeneous enhancement in arterial phases, most of the cases (n = 33) moderately or obviously enhanced. Only 17.2% (8/44) cases appeared as heterogeneous enhancement. And 86.4% cases (n = 38) were further enhanced in the venous phase. The CT images also revealed some of the metastases. Some liver metastasis cases have obvious homogeneous enhancement. CONCLUSIONS: CT and enhanced CT provide useful information regarding gastrointestinal neuroendocrine carcinomas' location, density, enhancement pattern, and some metastasis. These features are helpful to increase the diagnostic accuracy.


Asunto(s)
Carcinoma Neuroendocrino/diagnóstico por imagen , Neoplasias Gastrointestinales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Anciano , Anciano de 80 o más Años , Medios de Contraste , Femenino , Humanos , Inmunohistoquímica , Yohexol/análogos & derivados , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
17.
Acta Radiol ; 53(3): 312-7, 2012 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-22416261

RESUMEN

BACKGROUND: Diffusion tensor imaging (DTI) is a form of functional magnetic resonance imaging (MRI) that allows examination of the microstructural integrity of white matter in the brain. Dementia is a neurodegenerative disease, and DTI can provide indirect insights of the microstructural characteristics of brains in individuals with different forms of dementia. PURPOSE: To evaluate the value of DTI in the diagnosis and differential diagnosis of patients with subcortical ischemic vascular dementia (SIVD) and Alzheimer's disease (AD). MATERIAL AND METHODS: The study included 40 patients (20 AD patients and 20 SIVD patients) and 20 normal controls (NC). After routine MRI and DTI, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were measured and compared in regions of interest (ROI). RESULTS: Compared to NC and AD patients, SIVD patients had lower FA values and higher ADC values in the inferior-fronto-occipital fascicles (IFOF), genu of the corpus callosum (GCC), splenium of the corpus callosum (SCC), and superior longitudinal fasciculus (SLF). Compared to controls and SIVD patients, AD patients had lower FA values in the anterior frontal lobe, temporal lobe, hippocampus, IFOF, GCC, and CF; and higher ADC values in the temporal lobe and hippocampus. CONCLUSION: DTI can be used to estimate the white matter impairment in dementia patients. There were significant regional reductions of FA values and heightened ADC values in multiple regions in SIVD patients compared to AD patients. When compared with conventional MRI, DTI may provide a more objective method for the differential diagnosis of SIVD and AD disease patients who have only mild white matter alterations on T2-weighted imaging.


Asunto(s)
Enfermedad de Alzheimer/patología , Demencia Vascular/patología , Imagen de Difusión por Resonancia Magnética/métodos , Fibras Nerviosas Mielínicas/patología , Anciano , Anisotropía , Encéfalo/patología , Mapeo Encefálico/métodos , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Índice de Severidad de la Enfermedad
18.
Neurol India ; 60(1): 29-35, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22406776

RESUMEN

CONTEXT: There are currently few published studies that compare hippocampal volume (HCV) in children with temporal lobe epilepsy (TLE). Aims : T0 o compare HCVs in children with TLE and in relation to normal controls (NC), and to analyze HCV change in the acute phase in pediatric subjects using magnetic resonance imaging (MRI). Setting and Design : T0 he case group (n=24) was matched in gender and age range with NC subjects (n=24). Subjects were divided into three groups according to age: 2-5.9 years, 6-8.9 years and 9-13 years. MATERIALS AND METHODS: M0 anual measurements were used to obtain HCVs on oblique coronary MRI images obtained by three-dimensional magnetization-prepared rapid gradient-echo (3D-MPRAGE) sequence. Statistical Analyses : T0 he HCV was calculated and normalized. Paired t-tests were used to compare the right and left HCVs within each study group. Analysis of covariance (ANCOVA) was used to consider the impact of age and gender on HCVs. RESULTS: T0 wenty-two patients were diagnosed with definite/probable TLE, and two were non-syndromic focal epilepsy which was distributed in the 2-5.9 years group. The range of left to right mean HCVs of the case and NC group aged 2-13 years was 2014.14 ± 54.32 mm 3 to 2165.31 ± 80.99 mm 3 and 2015.46 ± 26.97 mm 3 to 2100.93 ± 57.33 mm 3 respectively. There were age-related differences in left and right HCV, but no effect of gender. Relative to NC subjects, cases group aged 2-5.9 years had significantly different HCVs, while no significant difference was found in the other two groups. There was significant difference in the right to left HCVs in the case subjects aged 2-5.9 years, but not in the other age groups. CONCLUSIONS: T0 he heterogeneity in the 2-5.9 years age cohort may relate to the increased HCVs. The HCV data from NC subjects may be used as a reference to assess hippocampal abnormalities in clinical practice.


Asunto(s)
Epilepsia del Lóbulo Temporal/patología , Hipocampo/patología , Imagen por Resonancia Magnética , Adolescente , Factores de Edad , Análisis de Varianza , Anticonvulsivantes/farmacología , Anticonvulsivantes/uso terapéutico , Niño , Preescolar , Imagen de Difusión por Resonancia Magnética , Epilepsia del Lóbulo Temporal/tratamiento farmacológico , Femenino , Lateralidad Funcional , Hipocampo/efectos de los fármacos , Humanos , Imagenología Tridimensional , Masculino , Factores Sexuales
19.
Arch Pharm Res ; 45(6): 367-389, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35713852

RESUMEN

The Astragalus polysaccharide is an important bioactive component derived from the dry root of Astragalus membranaceus. This review aims to provide a comprehensive overview of the research progress on the immunomodulatory effect of Astragalus polysaccharide and provide valuable reference information. We review the immunomodulatory effect of Astragalus polysaccharide on central and peripheral immune organs, including bone marrow, thymus, lymph nodes, spleen, and mucosal tissues. Furthermore, the immunomodulatory effect of Astragalus polysaccharide on a variety of immune cells is summarized. Studies have shown that Astragalus polysaccharide can promote the activities of macrophages, natural killer cells, dendritic cells, T lymphocytes, B lymphocytes and microglia and induce the expression of a variety of cytokines and chemokines. The immunomodulatory effect of Astragalus polysaccharide makes it promising for the treatment of many diseases, including cancer, infection, type 1 diabetes, asthma, and autoimmune disease. Among them, the anticancer effect is the most prominent. In short, Astragalus polysaccharide is a valuable immunomodulatory medicine, but further high-quality studies are warranted to corroborate its clinical efficacy.


Asunto(s)
Astragalus propinquus , Polisacáridos , Astragalus propinquus/metabolismo , Citocinas/metabolismo , Macrófagos , Polisacáridos/farmacología , Polisacáridos/uso terapéutico , Linfocitos T/metabolismo
20.
J Ethnopharmacol ; 292: 115165, 2022 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-35247475

RESUMEN

ETHNOPHARMACOLOGICAL RELEVANCE: Fufang Zhenzhu Tiaozhi capsule (FTZ) is a patented preparation of Chinese herbal medicine that has been used to treat hyperlipidemia, nonalcoholic fatty liver disease, atherosclerosis, and other glucolipid metabolic diseases (GLMDs) in the clinic for almost 10 years. However, how FTZ reduces albuminuria and attenuates diabetic kidney disease (DKD) progression is unknown. AIM OF THE STUDY: To clarify the effects of FTZ on DKD mice model and to explore the underlying mechanisms. MATERIALS AND METHODS: We used streptozotocin (STZ) (40 mg/kg/d, i.p. for 5 days, consecutively) combined with a high-fat diet (HFD) to induce a DKD mouse model, followed by FTZ (1, 2 g/kg/d, i.g.) treatment for 12 weeks. Losartan (30 mg/kg/d, i.g.) was used as a positive control. Measurements of 24 h proteinuria, serum creatinine (SCr), fasting blood glucose (FBG), total cholesterol (TC), triglyceride (TG), and low density lipoprotein cholesterol (LDL-C) levels and expression levels of fibronectin (FN), collagen IV, inflammatory cytokines, inflammatory cells, interleukin-17A (IL-17A) and the nuclear transcription factor-κB (NF-κB) signaling pathway in the kidney were examined. RESULTS: FTZ effectively decreased 24 h proteinuria, Scr, FBG, TC, TG, and LDL-C levels, inhibited mesangial cell expansion, reduced FN and collagen IV accumulation, and F4/80+ macrophage cell infiltration and Ly-6G+ neutrophil infiltration in glomerulus and tubulointerstitium. Furthermore, IL-17A production and the NF-κB signaling pathway were also downregulated after the administration of FTZ. CONCLUSION: FTZ might attenuate DKD progression, and inhibited kidney inflammation and fibrosis by inhibiting the expression of RORγT and IL-17A in vivo, offering novel insights for the clinical application of FTZ.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Medicamentos Herbarios Chinos , Animales , LDL-Colesterol , Colágeno , Diabetes Mellitus/tratamiento farmacológico , Nefropatías Diabéticas/tratamiento farmacológico , Medicamentos Herbarios Chinos/farmacología , Medicamentos Herbarios Chinos/uso terapéutico , Femenino , Humanos , Inflamación/tratamiento farmacológico , Interleucina-17 , Riñón , Masculino , Medicina Tradicional China , Ratones , FN-kappa B , Proteinuria/tratamiento farmacológico
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