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1.
Nature ; 620(7972): 200-208, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37407815

RESUMO

Cancer cells evade T cell-mediated killing through tumour-immune interactions whose mechanisms are not well understood1,2. Dendritic cells (DCs), especially type-1 conventional DCs (cDC1s), mediate T cell priming and therapeutic efficacy against tumours3. DC functions are orchestrated by pattern recognition receptors3-5, although other signals involved remain incompletely defined. Nutrients are emerging mediators of adaptive immunity6-8, but whether nutrients affect DC function or communication between innate and adaptive immune cells is largely unresolved. Here we establish glutamine as an intercellular metabolic checkpoint that dictates tumour-cDC1 crosstalk and licenses cDC1 function in activating cytotoxic T cells. Intratumoral glutamine supplementation inhibits tumour growth by augmenting cDC1-mediated CD8+ T cell immunity, and overcomes therapeutic resistance to checkpoint blockade and T cell-mediated immunotherapies. Mechanistically, tumour cells and cDC1s compete for glutamine uptake via the transporter SLC38A2 to tune anti-tumour immunity. Nutrient screening and integrative analyses show that glutamine is the dominant amino acid in promoting cDC1 function. Further, glutamine signalling via FLCN impinges on TFEB function. Loss of FLCN in DCs selectively impairs cDC1 function in vivo in a TFEB-dependent manner and phenocopies SLC38A2 deficiency by eliminating the anti-tumour therapeutic effect of glutamine supplementation. Our findings establish glutamine-mediated intercellular metabolic crosstalk between tumour cells and cDC1s that underpins tumour immune evasion, and reveal glutamine acquisition and signalling in cDC1s as limiting events for DC activation and putative targets for cancer treatment.


Assuntos
Sistema A de Transporte de Aminoácidos , Células Dendríticas , Glutamina , Neoplasias , Transdução de Sinais , Sistema A de Transporte de Aminoácidos/metabolismo , Fatores de Transcrição de Zíper de Leucina e Hélice-Alça-Hélix Básicos/metabolismo , Linfócitos T CD8-Positivos/imunologia , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Glutamina/metabolismo , Neoplasias/imunologia , Proteínas Proto-Oncogênicas/metabolismo , Proteínas Supressoras de Tumor/metabolismo
2.
Cell Rep ; 42(2): 112102, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36774548

RESUMO

Nutritional symbionts influence host reproduction, but the underlying molecular mechanisms are largely unclear. We previously found that the bacteriocyte symbiont Hamiltonella impacts the sex ratio of the whitefly Bemisia tabaci. Hamiltonella synthesizes folate by cooperation with the whitefly. Folate deficiency by Hamiltonella elimination or whitefly gene silencing distorted whitefly sex ratio, and folate supplementation restored the sex ratio. Hamiltonella deficiency or gene silencing altered histone H3 lysine 9 trimethylation (H3K9me3) level, which was restored by folate supplementation. Genome-wide chromatin immunoprecipitation-seq analysis of H3K9me3 indicated mitochondrial dysfunction in symbiont-deficient whiteflies. Hamiltonella deficiency compromised mitochondrial quality of whitefly ovaries. Repressing ovary mitochondrial function led to distorted whitefly sex ratio. These findings indicate that the symbiont-derived folate regulates host histone methylation modifications, which thereby impacts ovary mitochondrial function, and finally determines host sex ratio. Our study suggests that a nutritional symbiont can regulate animal reproduction in a way that differs from reproductive manipulators.


Assuntos
Hemípteros , Animais , Feminino , Hemípteros/genética , Razão de Masculinidade , Simbiose/genética , Enterobacteriaceae/genética , Ácido Fólico
3.
Adv Healthc Mater ; 11(14): e2200041, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35481899

RESUMO

As a typical tumor microenvironment-responsive therapy, chemodynamic therapy (CDT), producing hydroxyl radicals (• OH) to eliminate tumor cells, has demonstrated great promise. Nevertheless, there are still major challenges: • OH generated from endogenous H2 O2 is usually insufficient; the CDT effect is strongly dependent on the pre-reaction with glutathione. Addressing the challenges, Au@MnSe2 core-shell nanoagent for synergetic chemodynamic-photothermo-photocatalytic therapy combined with tetramodal imaging, including magnetic resonance imaging, computed tomography, photoacoustic, and infrared thermal imaging is reported. Distinct from the reported glutathione-depleting agents, Mn2+ in MnSe2 allows immediate generation of • OH, independent of pre-reaction. Meanwhile, Mn3+ consumes glutathione by its conversion to Mn2+ . The Au-MnSe2 combination promotes photothermal conversion and photocatalytic reaction, resulting in largely enhanced • OH generation from endogenous H2 O2 and significant hyperthermia. Meanwhile, immune response is effectively activated: the intratumoral expression of programmed cell death-1 and proinflammatory cytokines increase to 4-7 folds; the cytotoxic and helper T lymphocytes cells in the tumor area increase to more than 2.5-folds; an evident, temporary systemic immunostimulatory effect is demonstrated. High tumor inhibition rate (≈97.3%) and greatly prolonged survival are obtained. This highly-integrated design coordinating three different therapies with four different imaging modals provide new possibilities for high-performance theranostic nanoagents.


Assuntos
Hipertermia Induzida , Nanopartículas , Linhagem Celular Tumoral , Glutationa/metabolismo , Radical Hidroxila/metabolismo , Imunidade
4.
World J Clin Cases ; 9(29): 8740-8748, 2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34734052

RESUMO

BACKGROUND: Insomnia is the most common sleep disorder. It disrupts the patient's life and work, increases the risk of various health issues, and often requires long-term intervention. The financial burden and inconvenience of treatments discourage patients from complying with them, leading to chronic insomnia. AIM: To investigate the long-term home-practice effects of mindful breathing combined with a sleep-inducing exercise as adjunctive insomnia therapy. METHODS: A quasi-experimental design was used in the present work, in which the patients with insomnia were included and grouped based on hospital admission: 40 patients admitted between January and April 2020 were assigned to the control group, and 40 patients admitted between May and August 2020 were assigned to the treatment group. The control group received routine pharmacological and physical therapies, while the treatment group received instruction in mindful breathing and a sleep-inducing exercise in addition to the routine therapies. The Pittsburgh Sleep Quality Index (PSQI), Generalized Anxiety Disorder 7-item (GAD-7) scale, and Insomnia Severity Index (ISI) were utilized to assess sleep-quality improvement in the patient groups before the intervention and at 1 wk, 1 mo, and 3 mo postintervention. RESULTS: The PSQI, GAD-7, and ISI scores before the intervention and at 1 wk postintervention were not significantly different between the groups. However, compared with the control group, the treatment group exhibited significant improvements in sleep quality, daytime functioning, negative emotions, sleep latency, sleep duration, sleep efficiency, anxiety level, and insomnia severity at 1 and 3 mo postintervention (P < 0.05). The results showed that mindful breathing combined with the sleep-inducing exercise significantly improved the long-term effectiveness of insomnia treatment. At 3 mo, the PSQI scores for the treatment vs the control group were as follows: Sleep quality 0.98 ± 0.48 vs 1.60 ± 0.63, sleep latency 1.98 ± 0.53 vs 2.80 ± 0.41, sleep duration 1.53 ± 0.60 vs 2.70 ± 0.56, sleep efficiency 2.35 ± 0.58 vs 1.63 ± 0.49, sleep disturbance 1.68 ± 0.53 vs 2.35 ± 0.53, hypnotic medication 0.53 ± 0.64 vs 0.93 ± 0.80, and daytime dysfunction 1.43 ± 0.50 vs 2.48 ± 0.51 (all P < 0.05). The GAD-7 scores were 2.75 ± 1.50 vs 7.15 ± 2.28, and the ISI scores were 8.68 ± 2.26 vs 3.38 ± 1.76 for the treatment vs the control group, respectively (all P < 0.05). CONCLUSION: These simple, cost-effective, and easy-to-implement practices used in clinical or home settings could have profound significance for long-term insomnia treatment and merit wide adoption in clinical practice.

5.
Science ; 372(6538): 171-175, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33833120

RESUMO

Sexual reproduction in angiosperms relies on precise communications between the pollen and pistil. The molecular mechanisms underlying these communications remain elusive. We established that in Arabidopsis, a stigmatic gatekeeper, the ANJEA-FERONIA (ANJ-FER) receptor kinase complex, perceives the RAPID ALKALINIZATION FACTOR peptides RALF23 and RALF33 to induce reactive oxygen species (ROS) production in the stigma papillae, whereas pollination reduces stigmatic ROS, allowing pollen hydration. Upon pollination, the POLLEN COAT PROTEIN B-class peptides (PCP-Bs) compete with RALF23/33 for binding to the ANJ-FER complex, leading to a decline of stigmatic ROS that facilitates pollen hydration. Our results elucidate a molecular gating mechanism in which distinct peptide classes from pollen compete with stigma peptides for interaction with a stigmatic receptor kinase complex, allowing the pollen to hydrate and germinate.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Flores/metabolismo , Peptídeos/metabolismo , Pólen/fisiologia , Polinização , Proteínas Quinases/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Estado de Hidratação do Organismo , Espécies Reativas de Oxigênio/metabolismo
6.
Ann Palliat Med ; 10(4): 3783-3792, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33752429

RESUMO

BACKGROUND: This study aimed to explore the mechanism of Bushen Huoxue decoction (BHD) in treating intervertebral disc degeneration using the network pharmacology method. METHODS: Using of oral bioavailability >30% and drug-likeness >0.18 as the screening standards, the effective components and targets of BHD were retrieved from the TCMSP database and the BATMAN-TCM database. The disease targets of intervertebral disc degeneration were retrieved from the GeneCards database. The Wayne map of the interaction targets of the effective components of BHD and intervertebral disc degeneration were drawn using R software. The protein-protein interaction (PPI) network of common targets was constructed using STRING software. The network map of the interaction targets of the effective components of BHD-intervertebral disc degeneration was drawn using Cytoscape3.7.2 software. The GO and KEGG enrichment analysis of the common targets of BHD and intervertebral disc degeneration was performed using R software and the related plug-ins to screen the potential pathways and analyze its mechanism. RESULTS: This study screened 164 effective components of BHD, 131 interaction targets, 626 targets for degenerative disc disease, and 31 common interaction targets. IL6, VEGFA, CASP3, EGFR, ESR1, and MAPK8 appeared more frequently. These were mainly enriched in the AGE-RAGE, TNF, PI3K Akt, and MAPK signaling pathways. CONCLUSIONS: BHD mainly intervenes in intervertebral disc degeneration through IL6, VEGFA, CASP3, EGFR, ESR1, and MAPK8. The mechanism of the intervention of BHD on intervertebral disc degeneration may be related to AGE-RAGE, TNF, PI3K Akt, MAPK, and other signal pathways.


Assuntos
Medicamentos de Ervas Chinesas , Degeneração do Disco Intervertebral , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Degeneração do Disco Intervertebral/tratamento farmacológico , Medicina Tradicional Chinesa , Fosfatidilinositol 3-Quinases
7.
ISME J ; 15(6): 1655-1667, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33432136

RESUMO

Intracellular symbionts in insects often have reduced genomes. Host acquisition of genes from bacteria is an important adaptation that supports symbionts. However, the function of horizontally transferred genes in insect symbiosis remains largely unclear. The primary symbiont Portiera housed in bacteriocytes lacks pantothenate synthesis genes: panB and panC, which is presumably complemented by a fused gene panB-panC (hereafter panBC) horizontally transferred from bacteria in Bemisia tabaci MEAM1. We found panBC in many laboratory cultures, and species of B. tabaci shares a common evolutionary origin. We demonstrated that complementation with whitefly panBC rescued E. coli pantothenate gene knockout mutants. Portiera elimination decreased the pantothenate level and PanBC abundance in bacteriocytes, and reduced whitefly survival and fecundity. Silencing PanBC decreased the Portiera titer, reduced the pantothenate level, and decreased whitefly survival and fecundity. Supplementation with pantothenate restored the symbiont titer, PanBC level, and fitness of RNAi whiteflies. These data suggest that pantothenate synthesis requires cooperation and coordination of whitefly PanBC expression and Portiera. This host-symbiont co-regulation was mediated by the pantothenate level. Our findings demonstrated that pantothenate production, by the cooperation of a horizontally acquired, fused bacteria gene and Portiera, facilitates the coordination of whitefly and symbiont fitness. Thus, this study extends our understanding on the basis of complex host-symbiont interactions.


Assuntos
Hemípteros , Complexo Vitamínico B , Animais , Bactérias/genética , Escherichia coli , Simbiose
8.
J Med Chem ; 64(1): 385-403, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33382613

RESUMO

Synthetic cannabinoids, as exemplified by SDB-001 (1), bind to both CB1 and CB2 receptors and exert cannabimimetic effects similar to (-)-trans-Δ9-tetrahydrocannabinol, the main psychoactive component present in the cannabis plant. As CB1 receptor ligands were found to have severe adverse psychiatric effects, increased attention was turned to exploiting the potential therapeutic value of the CB2 receptor. In our efforts to discover novel and selective CB2 receptor agonists, 1 was selected as a starting point for hit molecule identification and a class of 1H-pyrazole-3-carboxamide derivatives were thus designed, synthesized, and biologically evaluated. Systematic structure-activity relationship investigations resulted in the identification of the most promising compound 66 as a selective CB2 receptor agonist with favorable pharmacokinetic profiles. Especially, 66 treatment significantly attenuated dermal inflammation and fibrosis in a bleomycin-induced mouse model of systemic sclerosis, supporting that CB2 receptor agonists might serve as potential therapeutics for treating systemic sclerosis.


Assuntos
Drogas Desenhadas/química , Descoberta de Drogas , Receptor CB2 de Canabinoide/agonistas , Escleroderma Sistêmico/tratamento farmacológico , Drogas Desenhadas/farmacocinética , Humanos , Relação Estrutura-Atividade
9.
ISME J ; 14(12): 2923-2935, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32690936

RESUMO

Symbionts can regulate animal reproduction in multiple ways, but the underlying physiological and biochemical mechanisms remain largely unknown. The presence of multiple lineages of maternally inherited, intracellular symbionts (the primary and secondary symbionts) in terrestrial arthropods is widespread in nature. However, the biological, metabolic, and evolutionary role of co-resident secondary symbionts for hosts is poorly understood. The bacterial symbionts Hamiltonella and Arsenophonus have very high prevalence in two globally important pests, the whiteflies Bemisia tabaci and Trialeurodes vaporariorum, respectively. Both symbionts coexist with the primary symbiont Portiera in the same host cell (bacteriocyte) and are maternally transmitted. We found that elimination of both Hamiltonella and Arsenophonous by antibiotic treatment reduced the percentage of female offspring in whiteflies. Microsatellite genotyping and cytogenetic analysis revealed that symbiont deficiency inhibited fertilization in whiteflies, leading to more haploid males with one maternal allele, which is consistent with distorted sex ratio in whiteflies. Quantification of essential amino acids and B vitamins in whiteflies indicated that symbiont deficiency reduced B vitamin levels, and dietary B vitamin supplementation rescued fitness of whiteflies. This study, for the first time, conclusively demonstrates that these two intracellular symbionts affect sex ratios in their whitefly hosts by regulating fertilization and supplying B vitamins. Our results reveal that both symbionts have the convergent function of regulating reproduction in phylogenetically-distant whitefly species. The 100% frequency, the inability of whiteflies to develop normally without their symbiont, and rescue with B vitamins suggests that both symbionts may be better considered co-primary symbionts.


Assuntos
Hemípteros , Complexo Vitamínico B , Animais , Feminino , Fertilização , Masculino , Razão de Masculinidade , Simbiose
10.
ISME J ; 14(10): 2542-2553, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32572143

RESUMO

Insect symbionts are widespread in nature and lateral gene transfer is prevalent in insect symbiosis. However, the function of horizontally transferred genes (HTGs) in insect symbiosis remains speculative, including the mechanism that enables insects to feed on plant phloem deficient in B vitamins. Previously, we found there is redundancy in biotin synthesis pathways from both whitefly Bemisia tabaci and symbiotic Hamiltonella due to the presence of whitefly HTGs. Here, we demonstrate that elimination of Hamiltonella decreased biotin levels but elevated the expression of horizontally transferred biotin genes in whiteflies. HTGs proteins exhibit specific expression patterns in specialized insect cells called bacteriocytes housing symbionts. Complementation with whitefly HTGs rescued E. coli biotin gene knockout mutants. Furthermore, silencing whitefly HTGs in Hamiltonella-infected whiteflies reduced biotin levels and hindered adult survival and fecundity, which was partially rescued by biotin supplementation. Each of horizontally transferred biotin genes are conserved in various laboratory cultures and species of whiteflies with geographically diverse distributions, which shares an evolutionary origin. We provide the first experimental evidence that biotin synthesized through acquired HTGs is important in whiteflies and may be as well in other animals. Our findings suggest that B vitamin provisioning in animal-microbe symbiosis frequently evolved from bacterial symbionts to animal hosts through horizontal gene transfer events. This study will also shed light on how the animal genomes evolve through functional transfer of genes with bacterial origin in the wider contexts of microbial ecology.


Assuntos
Biotina , Hemípteros , Animais , Bactérias/genética , Escherichia coli , Simbiose
11.
Fish Shellfish Immunol ; 98: 312-317, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31968268

RESUMO

Inactivated vaccines are often applied with adjuvants in commercial fish farming. Although some mineral or non-mineral oil adjuvants show efficient improvement with inactivated vaccines, but sometimes bring side effects such as tissue adhesion and granulomatous lesion at the injection site. CpG ODN is a novel type of soluble adjuvant which has been proved to possess excellent advantages in fish vaccine development. In this study, we designed a tandem sequence of CpG ODN synthesized in plasmid pcDNA 3.1, and an inactivated Vibrio anguillarum vaccine developed in our previous work was chosen for determining the efficiency of the CpG-riched plasmids (pCpG) as an adjuvant. Results showed that pCpG we designed can offer higher immunoprotection with the vaccine. Interestingly, even below the minimum immune dosage of the vaccine, a high RPS of 84% was observed once the vaccine was administrated with the pCpG. Serum specific antibody titer, superoxide dismutase and total protein were enhanced and some immune genes related to both innate and adaptive immune response were upregulated, implying an effective auxiliary function of the pCpG. Totally, our study suggested that the pCpG is a potential and available adjuvant for turbot vaccine development.


Assuntos
Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Linguados/imunologia , Oligodesoxirribonucleotídeos/imunologia , Vibrioses/veterinária , Vibrio/imunologia , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/síntese química , Animais , Vacinas Bacterianas/administração & dosagem , Doenças dos Peixes/microbiologia , Linguados/microbiologia , Regulação da Expressão Gênica/imunologia , Imunidade Humoral , Oligodesoxirribonucleotídeos/administração & dosagem , Plasmídeos/administração & dosagem , Plasmídeos/imunologia , Taxa de Sobrevida , Vacinação/veterinária , Vacinas de Produtos Inativados/administração & dosagem , Vacinas de Produtos Inativados/imunologia , Vibrioses/microbiologia , Vibrioses/prevenção & controle
12.
Mol Med Rep ; 19(2): 1238-1247, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30569113

RESUMO

High-performance liquid chromatography (HPLC) is an efficient method that is widely used to assess the quality of traditional Chinese medicine (TCM). It is well known that the quality of TCM has a direct effect on its efficacy; therefore, in order to thoroughly explain how TCM exerts its efficacy, it is necessary to characterize its active ingredients and assess their quality. The application of the spectrum­effect method is crucial for determining the pharmacological basis of materials. The aim of the present study was to examine the correlation between chemical spectra and estrogenic activity of Cuscuta chinensis Lam., in order to reveal active compounds with potential therapeutic effects. The spectra of Cuscuta chinensis Lam. were recorded using HPLC, and estrogenic activity was determined using a uterus growth test and MTT assay. Combination of the results of bivariate analysis, principal component analysis and Gray relational analysis identified 19 active compounds, as follows: Quercetin­3­O­(2'­O­α­rhamnosy­6'­O­malony)­â€‹ß­D­glucoside, ka-empferol­3­O­ß­D­aplosyl­(1→2)­â€‹[­α­â€‹L­rhamnosy­(1→6)]­ß-wD-glucoside, 6­O­(E)­P­coumaroyl)­ß­â€‹D­fructofuranosyl­(2→1)­α­D­glucopyranoside, kaempferol­7­rhamnosy, kaempferol­3­ß­D-glucuronide, apigenin, 4­caffeoyl­5­coumaroylquinic acid, kaempferol­3­arabofuranoside, quercetin­3­O-ß­D-apiofuranosyl-(1→2)-ß­D­galactoside, dicaffeoylquinic acid, hyperin, quercitin, isorhamnetin, chlorogenic acid, quercetin, quercltrin­2''­gallate, quercetin­3, 7­α­L­dirhamnoside and stigmasterol, as well as one unknown compound. The present study laid a foundation for in vivo metabolic studies regarding Cuscuta chinensis Lam. and for the development of its clinical application.


Assuntos
Cuscuta/química , Estrogênios/química , Extratos Vegetais/química , Animais , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química , Feminino , Espectrometria de Massas/métodos , Camundongos
13.
Huan Jing Ke Xue ; 39(3): 1129-1140, 2018 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965457

RESUMO

The proliferation of diatoms is an ecological disaster that harms the water quality of many reservoirs in China. In order to reveal the driving factors of abnormal algal blooms in reservoirs, phytoplankton community structure and the associated environmental factors from 2009 to 2016 from Shahe Reservoir in Tianmuhu were analyzed. Results showed that diatoms and there dominant genus were predominately driven by temperature, and the relationship between hydrology and nutrition was insignificant. Distinct relationships were recorded between different diatom genera and temperature over the past eight years. The optimum growth temperature of diatoms and Synedra were both 27℃, while that for Cyclotella and Achnanthes were both 19℃. Low temperature was suitable for the growth of Melosira, and its growth was compromised with increasing temperature. In a multivariable statistical analysis of the dominant diatom genus and the associated environmental factors, we found that the dominant diatom genus responded differently to the associated environmental factors. The total biomass of the diatom and the biomass of Synedra and Achnanthes were significantly and positively correlated with rainfall (P<0.05). The biomass of Cyclotella was significantly and positively correlated with total phosphorus, rainfall, and water level (P<0.05) and significantly and negatively correlated with water exchange rate (P<0.05). The biomass of Melosira was significantly and positively correlated with total phosphorus. The annual peak biomass of diatoms can be predicted by a multiple regression model with independent variables, including rainfall intensity, dissolved total phosphorus, and the accumulated temperature in winter and spring. Our results indicated that the proliferation of diatoms responds significantly to hydrological and meteorological factors while insignificantly to nitrogen and phosphorus loading. External load reduction is needed to maintain a good water quality in the reservoir. In addition, extreme weather conditions should be given attention to provide an early warning for diatom proliferation.


Assuntos
Diatomáceas/crescimento & desenvolvimento , Proliferação Nociva de Algas , Fósforo/análise , Temperatura , Biomassa , China , Água Doce/análise , Fitoplâncton/crescimento & desenvolvimento , Estações do Ano
14.
Huan Jing Ke Xue ; 39(5): 2145-2153, 2018 May 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965514

RESUMO

The effects of Myriophyllum spicatum L. with developed root systems and rootless Ceratophyllum demersum on the concentration and proportion of different phosphorus fractions in the overlying water and the interstitial water were investigated by batch simulation experiments. The effects of different types of submerged macrophytes on the phosphorus fraction in the overlying water and interstitial water were explored. The results indicated a significant influence on the concentration of dissolved phosphorus in the overlying water and interstitial water by the growth of Myriophyllum spicatum L. and Ceratophyllum demersum. ① The absorptivities of DTP, SRP, and DOP by Myriophyllum spicatum L. in the overlying water were 7.0%, 11.7%, and 3.5%, respectively, and in the interstitial water were 20.8%, 12.5%, and 48.4%, respectively. ② The absorptivities of DTP, SRP, and DOP by Ceratophyllum demersum in the overlying water were 30.3%, 54.9%, and 13.2%, respectively, and in the interstitial water were 19.3%, 3.8%, and 30.4%, respectively. ③ The content of SRP in Myriophyllum spicatum L. group, Ceratophyllum demersum group, and the control group decreased 13.0%, 34.0%, and -0.9%, respectively; the PP increased 18.2%, 33.1%, and 4.2%, respectively; and the DOP increased 7.2%, 17.68%, and -4.35%, respectively. The results provide reference for eutrophic lake ecologic restoration.


Assuntos
Lagos/química , Magnoliopsida/metabolismo , Fósforo/análise , Poluentes Químicos da Água/análise , Água
15.
Environ Sci Pollut Res Int ; 25(10): 10014-10028, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29380198

RESUMO

Reducing external nutrient loads is the first step for controlling eutrophication. Here, we identified external nutrient reduction requirements and potential of strategies for achieving reductions to remediate a eutrophic water body, Lake Taihu, China. A mass balance approach based on the entire lake was used to identify nutrient reduction requirements; an empirical export coefficient approach was introduced to estimate the nutrient reduction potential of the overall program on integrated regulation of Taihu Lake Basin (hereafter referred to as the "Guideline"). Reduction requirements included external total nitrogen (TN) and total phosphorus (TP) loads, which should be reduced by 41-55 and 25-50%, respectively, to prevent nutrient accumulation in Lake Taihu and to meet the planned water quality targets. In 2010, which is the most seriously polluted calendar year during the 2008-2014 period, the nutrient reduction requirements were estimated to be 36,819 tons of N and 2442 tons of P, and the potential nutrient reduction strategies would reduce approximately 25,821 tons of N and 3024 tons of P. Since there is a net N remaining in the reduction requirements, it should be the focus and deserves more attention in identifying external nutrient reduction strategies. Moreover, abatement measures outlined in the Guideline with high P reduction potential required large monetary investments. Achieving TP reduction requirement using the cost-effective strategy costs about 80.24 million USD. The design of nutrient reduction strategies should be enacted according to regional and sectoral differences and the cost-effectiveness of abatement measures.


Assuntos
Monitoramento Ambiental , Lagos , Nitrogênio/análise , Fósforo/análise , Poluentes Químicos da Água/análise , China , Eutrofização , Qualidade da Água
16.
Lancet ; 389(10081): 1799-1808, 2017 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-28325638

RESUMO

BACKGROUND: Dual antiplatelet therapy (DAPT), aspirin plus a P2Y12 inhibitor, is the standard antithrombotic treatment following acute coronary syndromes. The factor Xa inhibitor rivaroxaban reduced mortality and ischaemic events when added to DAPT, but caused increased bleeding. The safety of a dual pathway antithrombotic therapy approach combining low-dose rivaroxaban (in place of aspirin) with a P2Y12 inhibitor has not been assesssed in acute coronary syndromes. We aimed to assess rivaroxaban 2·5 mg twice daily versus aspirin 100 mg daily, in addition to clopidogrel or ticagrelor (chosen at investigator discretion before randomisation), for patients with acute coronary syndromes started within 10 days after presentation and continued for 6-12 months. METHODS: In this double-blind, multicentre, randomised trial (GEMINI-ACS-1) done at 371 clinical centres in 21 countries, eligible patients were older than 18 years with unstable angina, non-ST segment elevation myocardial infarction (NSTEMI) or ST segment elevation myocardial infarction (STEMI), with positive cardiac biomarkers and either ischaemic electrocardiographic changes or an atherosclerotic culprit lesion identified during angiography. Participants were randomly assigned (1:1) within 10 days after admission for the index acute coronary syndromes event to either aspirin or rivaroxaban based on a computer-generated randomisation schedule. Randomisation was balanced by using randomly permuted blocks with size of four and was stratified based on the background P2Y12 inhibitor (clopidogrel or ticagrelor) intended to be used at the time of randomisation. Investigators and patients were masked to treatment assignment. Patients received a minimum of 180 days of double-blind treatment with rivaroxaban 2·5 mg twice daily or aspirin 100 mg daily. The choice of clopidogrel or ticagrelor during trial conduct was not randomised and was based on investigator preference. The primary endpoint was thrombolysis in myocardial infarction (TIMI) clinically significant bleeding not related to coronary artery bypass grafting (CABG; major, minor, or requiring medical attention) up to day 390. Primary analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT02293395. FINDINGS: Between April 22, 2015, and Oct 14, 2016, 3037 patients with acute coronary syndromes were randomly assigned; 1518 to receive aspirin and 1519 to receive rivaroxaban. 1704 patients (56%) were in the ticagrelor and 1333 (44%) in the clopidogrel strata. Median duration of treatment was 291 days (IQR 239-354). TIMI non-CABG clinically significant bleeding was similar with rivaroxaban versus aspirin therapy (total 154 patients [5%]; 80 participants [5%] of 1519 vs 74 participants [5%] of 1518; HR 1·09 [95% CI 0·80-1·50]; p=0·5840). INTERPRETATION: A dual pathway antithrombotic therapy approach combining low-dose rivaroxaban with a P2Y12 inhibitor for the treatment of patients with acute coronary syndromes had similar risk of clinically significant bleeding as aspirin and a P2Y12 inhibitor. A larger, adequately powered trial would be required to definitively assess the efficacy and safety of this approach. FUNDING: Janssen Research & Development and Bayer AG.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Aspirina/uso terapêutico , Hemorragia/induzido quimicamente , Antagonistas do Receptor Purinérgico P2Y/uso terapêutico , Rivaroxabana/uso terapêutico , Adenosina/administração & dosagem , Adenosina/análogos & derivados , Adenosina/uso terapêutico , Idoso , Aspirina/administração & dosagem , Clopidogrel , Angiografia Coronária/métodos , Método Duplo-Cego , Quimioterapia Combinada/métodos , Eletrocardiografia/métodos , Inibidores do Fator Xa/uso terapêutico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/diagnóstico por imagem , Infarto do Miocárdio/tratamento farmacológico , Infarto do Miocárdio/fisiopatologia , Inibidores da Agregação Plaquetária/uso terapêutico , Antagonistas do Receptor Purinérgico P2Y/administração & dosagem , Rivaroxabana/administração & dosagem , Terapia Trombolítica/métodos , Ticagrelor , Ticlopidina/administração & dosagem , Ticlopidina/análogos & derivados , Ticlopidina/uso terapêutico , Resultado do Tratamento
17.
Huan Jing Ke Xue ; 38(10): 4160-4168, 2017 Oct 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965199

RESUMO

Monthly investigations of the phytoplankton community and the associated environmental drivers during the past eight years in the Shahe Reservoir, Jiangsu Province, China revealed the spatial and temporal variations of phytoplankton and the associated driving factors in the reservoir. The results show that the concentrations of total nitrogen (TN), total phosphorous (TP), turbidity (Turb), suspended solids (SS), and chlorophyll-a (CHL) were the highest in the upstream tributaries and the lowest in the downstream-linked reservoir. In contrast, the highest Secchi disk depth (SDD) was recorded in the Shahe Reservoir and that the lowest in the upstream tributaries. Significant differences in water quality indices were recorded among the upstream tributaries, the transition region, and the downstream-linked reservoir area (ANOVA, P<0.05). The biomass of phytoplankton was the highest in the upstream tributaries and the lowest in the reservoir. The highest biomass of phytoplankton was recorded in the summer and the lowest in the winter. Synedra, Cyclotella, Cryptomonas, and Achnanthes were the dominant genera in the spring; Synedra, Cryptomonas, Raphidiopsis, and Phormidium were dominant in the summer; Cryptomonas, Synedra, Raphidiopsis, and Aphanizomenon were dominant in the autumn; and Cryptomonas, Synedra, Achnanthes, and Cyclotella were dominant in the winter. Synedra and Cryptomonas were the dominant genera throughout the year. The correlation analysis shows that TP, water temperature, and SDD were the most important driving factors for the spatial and temporal variations of phytoplankton. Notable spatial differences were recorded for Cryptomonas, while minimal variations were recorded for the remaining species. A smaller number sampling sites and a higher sampling frequency are needed to characterize the phytoplankton community in the Shahe Reservoir.


Assuntos
Monitoramento Ambiental , Eutrofização , Água Doce , Fitoplâncton/crescimento & desenvolvimento , Biomassa , China , Cianobactérias , Nitrogênio/análise , Fósforo/análise , Estações do Ano , Análise Espaço-Temporal
18.
ChemMedChem ; 11(19): 2188-2193, 2016 10 06.
Artigo em Inglês | MEDLINE | ID: mdl-27624789

RESUMO

Iron chelation therapy has been recognized as a promising antitumor therapeutic strategy. Herein we report a novel theranostic agent for targeted iron chelation therapy and near-infrared (NIR) optical imaging of cancers. The theranostic agent was prepared by incorporation of a polyaminocarboxylate-based cytotoxic chelating agent (N-NE3TA; 7-[2-[(carboxymethyl)amino]ethyl]-1,4,7-triazacyclononane-1,4-diacetic acid) and a NIR fluorescent cyanine dye (Cy5.5) onto a tumor-targeting transferrin (Tf). The N-NE3TA-Tf conjugate (without Cy5.5) was characterized and evaluated for antiproliferative activity in HeLa, HT29, and PC3 cancer cells, which have elevated expression levels of the transferrin receptor (TfR). The N-NE3TA-Tf conjugate displayed significant inhibitory activity against all three cancer cell lines. The NIR dye Cy5.5 was then incorporated into N-NE3TA-Tf, and the resulting cytotoxic and fluorescent transferrin conjugate N-NE3TA-Tf-Cy5.5 was shown by microscopy to enter TfR-overexpressing cancer cells. This theranostic conjugate has potential application for dual use in targeted iron chelation cancer therapy and NIR fluorescence imaging.


Assuntos
Antineoplásicos/farmacologia , Carbocianinas/química , Ácidos Carboxílicos/química , Quelantes/farmacologia , Imagem Óptica/métodos , Poliaminas/química , Transferrina/química , Antineoplásicos/síntese química , Antineoplásicos/química , Carbocianinas/farmacologia , Ácidos Carboxílicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Quelantes/síntese química , Quelantes/química , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Estrutura Molecular , Poliaminas/farmacologia , Espectroscopia de Luz Próxima ao Infravermelho , Relação Estrutura-Atividade , Transferrina/farmacologia , Células Tumorais Cultivadas
19.
Clin Trials ; 13(3): 344-51, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-26908543

RESUMO

BACKGROUND: The potential impact of missing data on the results of clinical trials has received heightened attention recently. A National Research Council study provides recommendations for limiting missing data in clinical trial design and conduct, and principles for analysis, including the need for sensitivity analyses to assess robustness of findings to alternative assumptions about the missing data. A Food and Drug Administration advisory committee raised missing data as a serious concern in their review of results from the ATLAS ACS 2 TIMI 51 study, a large clinical trial that assessed rivaroxaban for its ability to reduce the risk of cardiovascular death, myocardial infarction or stroke in patients with acute coronary syndrome. This case study describes a variety of measures that were taken to address concerns about the missing data. METHODS: A range of analyses are described to assess the potential impact of missing data on conclusions. In particular, measures of the amount of missing data are discussed, and the fraction of missing information from multiple imputation is proposed as an alternative measure. The sensitivity analysis in the National Research Council study is modified in the context of survival analysis where some individuals are lost to follow-up. The impact of deviations from ignorable censoring is assessed by differentially increasing the hazard of the primary outcome in the treatment groups and multiply imputing events between dropout and the end of the study. Tipping-point analyses are described, where the deviation from ignorable censoring that results in a reversal of significance of the treatment effect is determined. A study to determine the vital status of participants lost to follow-up was also conducted, and the results of including this additional information are assessed. RESULTS: Sensitivity analyses suggest that findings of the ATLAS ACS 2 TIMI 51 study are robust to missing data; this robustness is reinforced by the follow-up study, since inclusion of data from this study had little impact on the study conclusions. CONCLUSION: Missing data are a serious problem in clinical trials. The methods presented here, namely, the sensitivity analyses, the follow-up study to determine survival of missing cases, and the proposed measurement of missing data via the fraction of missing information, have potential application in other studies involving survival analysis where missing data are a concern.


Assuntos
Síndrome Coronariana Aguda/tratamento farmacológico , Inibidores do Fator Xa/uso terapêutico , Perda de Seguimento , Pacientes Desistentes do Tratamento , Rivaroxabana/uso terapêutico , Doenças Cardiovasculares/mortalidade , Método Duplo-Cego , Humanos , Estudos Multicêntricos como Assunto , Infarto do Miocárdio/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Acidente Vascular Cerebral/epidemiologia , Análise de Sobrevida
20.
J Food Sci ; 80(9): H2079-87, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26243042

RESUMO

As a famous health food in China, Cistanche deserticola (C. deserticola) suggested an estrogenic activity according to our previous study. However, no one clarifies its active material basis to date. To find more potentially active constituents and elucidate metabolic pathways of metabolites, a method to simultaneously analyze multiple absorbed constituents and metabolites from C. deserticola in rat serum and urine was established using high-performance liquid chromatography/quadrupole time-of-flight mass spectrometry (HPLC/Q-TOF-MS). Based on HPLC/Q-TOF-MS method, a total of 24 components, involving 9 prototype constituents and 15 metabolites in rat serum and urine samples, were tentatively identified based on retention time, ultraviolet spectrum, MS data, compound fragmentation laws, published literatures, and reference substances. Most of the compounds existed in the form of metabolites. The proposed metabolic pathways of main metabolites were discussed, including methylation, demethylation, hydrolysis, hydroxylation, acetoxylation, glucuronidation, dehydrogenation, sulfation, esterification, and so on. Phenylethanoid glycosides were extensively metabolized and mutually transformed in vivo. This investigation provided valuable information for further study of the active ingredients and action mechanism of C. deserticola.


Assuntos
Cistanche/química , Medicamentos de Ervas Chinesas/farmacocinética , Administração Oral , Animais , China , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Medicamentos de Ervas Chinesas/metabolismo , Glicosídeos/metabolismo , Espectrometria de Massas/métodos , Álcool Feniletílico/metabolismo , Ratos
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