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1.
Small ; 19(38): e2300122, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37144423

RESUMO

As a clean and effective approach, the introduction of external magnetic fields to improve the performance of catalysts has attracted extensive attention. Owing to its room-temperature ferromagnetism, chemical stability, and earth abundance, VSe2 is expected to be a promising and cost-effective ferromagnetic electrocatalyst for the accomplishment of high-efficient spin-related OER kinetics. In this work, a facile pulsed laser deposition (PLD) method combined with rapid thermal annealing (RTA) treatment is used to successfully confine monodispersed 1T-VSe2 nanoparticles in amorphous carbon matrix. As expected, with external magnetic fields of 800 mT stimulation, the confined 1T-VSe2 nanoparticles exhibit highly efficient oxygen evolution reaction (OER) catalytic activity with an overpotential of 228 mV for 10 mA cm-2 and remarkable durability without deactivation after >100 h OER operation. The experimental results together with theoretical calculations illustrate that magnetic fields can facilitate the surface charge transfer dynamics of 1T-VSe2 , and modify the adsorption-free energy of *OOH, thus finally improving the intrinsic activity of the catalysts. This work realizes the application of ferromagnetic VSe2 electrocatalyst in highly efficient spin-dependent OER kinetics, which is expected to promote the application of transition metal chalcogenides (TMCs) in external magnetic field-assisted electrocatalysis.

2.
Environ Res ; 231(Pt 3): 116251, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37245569

RESUMO

High phosphorus (P) concentrations are commonly observed in lakes during algal blooms despite massive efforts on external nutrient reduction. However, the knowledge about the relative contribution of internal P loading linked with algal blooms on lake phosphorus (P) dynamics remains limited. To quantify the effect of internal loading on P dynamics, we conducted extensive spatial and multi-frequency nutrient monitoring from 2016 to 2021 in Lake Taihu, a large shallow eutrophic lake in China, and its tributaries (2017-2021). The in-lake P stores (ILSP) and external loading were estimated and then internal P loading was quantified from the mass balance equation. The results showed that the in-lake total P stores (ILSTP) ranged from 398.5 to 1530.2 tons (t), and exhibited a dramatic intra- and inter-annual variability. The annual internal TP loading released from sediment ranged from 1054.3 to 1508.4 t, which was equivalent to 115.6% (TP loading) of the external inputs on average, and responsible for the fluctuations of ILSTP on a weekly scale. High-frequency observations exemplified that ILSTP increased by 136.4% during algal blooms in 2017, while by only 47.2% as a result of external loading after heavy precipitation in 2020. Our study demonstrated that both bloom-induced internal loading and storm-induced external loading are likely to run counter significantly to watershed nutrient reduction efforts in large shallow lakes. More importantly, bloom-induced internal loading is higher than storm-induced external loading over the short term. Given the positive feedback loop between internal P loadings and algal bloom in eutrophic lakes, which explains the significant fluctuation of P concentration while nitrogen concentration decreased. It is emphasized that internal loading and ecosystem restoration are unignorable in shallow lakes, particularly in the algal-dominated region.


Assuntos
Ecossistema , Lagos , Fósforo/análise , Monitoramento Ambiental/métodos , Nitrogênio/análise , Eutrofização , China
3.
J Environ Manage ; 306: 114476, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35051816

RESUMO

Eutrophication and its associated algal blooms are principal environmental challenges confronting lakes worldwide. The empirical relationships between nutrient (total nitrogen, TN; total phosphorus, TP) and chlorophyll a (Chla) level are widely used as a theoretical basis for lake eutrophication management. Here, seasonal environmental variables and Chla from 2005 to 2020 in Chinese shallow eutrophic Lake Taihu were examined and Chla-nutrient equations in the entire period and annually from 2005 to 2020 were explored using 95% quantile regression model. The results showed robust linear relationships of logChla-logTN and logChla-logTP in the vast majority of cases. Based on Chla-nutrient equations in the entire study period, 0.69 mg/L TN and 52 µg/L TP are recommended as nutrient threshold in Lake Taihu. Furthermore, the results revealed increasing Chla sensitivity to nutrient for each study month (i.e. February, May, August, and November) from 2005 to 2020, whose drivers included increase in water temperature and water level, decrease in wind speed, mass ratio of nitrogen to phosphorus, and grazing effect. It is noteworthy that atmospheric stilling is likely to be the key climatic factor promoting annual peak Chla in Lake Taihu. For one, the deviations of the sub-index of Trophic State Index indicated that light is a critical limiting factor of summer Chla in Lake Taihu. For another, calmer water mainly due to atmospheric stilling decreased near 40% non-algal turbidity and a substantially increased buoyant cyanobacteria during the study period, improving phytoplankton "light niche". Thus, increasing algal sensitivity to nutrient occurred until the additional algal-turbidity induce further light limitations or the exhaustion of TN (or TP) cause nutrient limitation. Given atmospheric stilling is a global phenomenon, this study would affect future algal bloom mitigation efforts in shallow lakes as temperature is always the focus in the recent literatures on global climate change.


Assuntos
Monitoramento Ambiental , Lagos , China , Clorofila , Clorofila A , Eutrofização , Nitrogênio/análise , Nutrientes , Fósforo/análise
4.
J Environ Manage ; 318: 115542, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35763998

RESUMO

Knowledge of phytoplankton limiting factors is essential for cost-efficient lake eutrophication management. Herein, we propose a statistical framework to explore site-specific phytoplankton limiting factors and their dependence on water depth (WD) in 54 lakes in the Chinese Eastern Plains ecoregion. First, the maximal chlorophyll a (Chla) response to total N (TN) or P (TP), representing a region-specific "standard" model where phytoplankton were primarily N- or P-limited, was quantified using a 95% quantile regression. Second, site-specific limiting factors were identified using analogical residual analysis. N- or P-limitation was inferred if FractionTN (i.e. fraction of Chla observed and predicted by the "standard" model for a given TN) > 0.95 or FractionTP >0.95; if both FractionTN and FractionTP <0.95 in a specific environmental condition (e.g. high non-algal turbidity), light limitation was suggested. As a result, 5%, 7%, 4%, 36%, 16%, 2%, and 30% of the sampling sites were limited by N, P, N+P, light availability, rapid flushing, abundant macrophytes, and unmeasured factors, respectively. Bloom control suggestions in the short run are proposed considering these actual limiting factors. Furthermore, the maximal FractionTN or FractionTP response to WD was explored, reflecting the effect of WD on FractionTN (or FractionTP) without significant confounders. The results indicated that phytoplankton in the studied freshwaters would be potentially light-limited, N-limited, N+P-co-limited, or P-limited depending on WD (<1.8, 1.8-2.1, 2.1-5.2, or >5.2 m, respectively), because N will gradually become surplus with increasing WD, while at very shallow depths, strong sediment re-suspension induces light limitation. This finding implies that long-term nutrient management strategies in the studied freshwaters that have WDs of 0-2.1, 2.1-5.2, and >5.2 m can entail control of N, N+P, and P, respectively. This study provides essential information for formulating context-dependent bloom control for lakes in our study area and serves as a valuable reference for developing a cost-efficient eutrophication management framework for other regions.


Assuntos
Cianobactérias , Lagos , China , Clorofila A , Monitoramento Ambiental , Eutrofização , Nitrogênio/análise , Fósforo/análise , Fitoplâncton , Água
5.
J Environ Sci (China) ; 111: 229-239, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34949352

RESUMO

Eutrophication and harmful cyanobacterial blooms threaten water resources all over the world. There is a great controversy about controlling only phosphorus or controlling both nitrogen and phosphorus in the management of lake eutrophication. The primary argument against the dual nutrients control of eutrophication is that nitrogen fixation can compensate the nitrogen deficits. Thus, it is of great necessary to study the factors that can significantly affect the nitrogen fixation. Due to the difference of climate and human influence, the water quality of different lakes (such as water temperature, N:P ratio and water residence time) is also quite different. Numerous studies have reported that the low N:P ratio can intensify the nitrogen fixation capacities. However, the effects of temperature and water residence time on the nitrogen fixation remain unclear. Thus, 30 shallows freshwater lakes in the eastern plain of China were selected to measure dissolved N2 and Ar concentrations through N2: Ar method using a membrane inlet mass spectrometer to quantify the nitrogen fixation capacities and investigate whether the temperature and water residence time have a great impact on nitrogen fixation. The results have shown that the short lake water residence time can severely inhibit the nitrogen fixation capacities through inhibiting the growth of nitrogen-fixing cyanobacteria, changing the N:P ratio and resuspending the solids from sediments. Similarly, lakes with low water temperature also have a low nitrogen fixation capacity, suggesting that controlling nitrogen in such lakes is feasible if the growth of cyanobacteria is limited by nitrogen.


Assuntos
Cianobactérias , Eutrofização , China , Humanos , Lagos , Nitrogênio/análise , Fósforo/análise , Temperatura
6.
Cell Commun Signal ; 19(1): 83, 2021 08 09.
Artigo em Inglês | MEDLINE | ID: mdl-34372855

RESUMO

BACKGROUND: The positive transcription elongation factor b (P-TEFb) kinase activity is involved in the process of transcription. Cyclin-dependent kinase 9 (CDK9), a core component of P-TEFb, regulates the process of transcription elongation, which is associated with differentiation and apoptosis in many cancer types. Wogonin, a natural CDK9 inhibitor isolated from Scutellaria baicalensis. This study aimed to investigate the involved molecular mechanisms of wogonin on anti- chronic myeloid leukemia (CML) cells. MATERIALS AND METHODS: mRNA and protein levels were analysed by RT-qPCR and western blot. Flow cytometry was used to assess cell differentiation and apoptosis. Cell transfection, immunofluorescence analysis and co-immunoprecipitation (co-IP) assays were applied to address the potential regulatory mechanism of wogonin. KU-812 cells xenograft NOD/SCID mice model was used to assess and verify the mechanism in vivo. RESULTS: We reported that the anti-CML effects in K562, KU-812 and primary CML cells induced by wogonin were regulated by P-TEFb complex. We also confirmed the relationship between CDK9 and erythroid differentiation via knockdown the expression of CDK9. For further study the mechanism of erythroid differentiation induced by wogonin, co-IP experiments were used to demonstrate that wogonin increased the binding between GATA-1 and FOG-1 but decreased the binding between GATA-1 and RUNX1, which were depended on P-TEFb. Also, wogonin induced apoptosis and decreased the mRNA and protein levels of MCL-1 in KU-812 cells, which is the downstream of P-TEFb. In vivo studies showed wogonin had good anti-tumor effects in KU-812 xenografts NOD/ SCID mice model and decreased the proportion of human CD45+ cells in spleens of mice. We also verified that wogonin exhibited anti-CML effects through modulating P-TEFb activity in vivo. CONCLUSIONS: Our study indicated a special mechanism involving the regulation of P-TEFb kinase activity in CML cells, providing evidences for further application of wogonin in CML clinical treatment. Video Abstract.


Assuntos
Quinase 9 Dependente de Ciclina/genética , Flavanonas/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Fator B de Elongação Transcricional Positiva/genética , Animais , Apoptose/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quinase 9 Dependente de Ciclina/antagonistas & inibidores , Fator de Transcrição GATA1/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Camundongos , Terapia de Alvo Molecular , Complexos Multiproteicos/antagonistas & inibidores , Complexos Multiproteicos/genética , Proteínas Nucleares/genética , Fosforilação/efeitos dos fármacos , Fator B de Elongação Transcricional Positiva/antagonistas & inibidores , Fatores de Transcrição/genética , Ensaios Antitumorais Modelo de Xenoenxerto
7.
Acta Pharmacol Sin ; 42(2): 290-300, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32747719

RESUMO

Cutaneous T-cell lymphoma (CTCL) is characterized by a heterogeneous group of extranodal non-Hodgkin lymphomas, in which monoclonal T lymphocytes infiltrate the skin. LW-213, a derivative of wogonin, was found to induce cell apoptosis in chronic myeloid leukemia (CML). In this study, we investigated the effects of LW-213 on CTCL cells and the underlying mechanisms. We showed that LW-213 (1-25 µM) dose-dependently inhibited human CTCL cell lines (Hut-102, Hut-78, MyLa, and HH) with IC50 values of around 10 µM, meanwhile it potently inhibited primary leukemia cells derived from peripheral blood of T-cell lymphoma patients. We revealed that LW-213-induced apoptosis was accompanied by ROS formation and the release of calcium from endoplasmic reticulum (ER) through IP3R-1channel. LW-213 selectively activated CHOP and induced apoptosis in Hut-102 cells via activating PERK-eIF2α-ATF4 pathway. Interestingly, the degree of apoptosis and expression of ER stress-related proteins were alleviated in the presence of either N-acetyl cysteine (NAC), an ROS scavenger, or 2-aminoethyl diphenylborinate (2-APB), an IP3R-1 inhibitor, implicating ROS/calcium-dependent ER stress in LW-213-induced apoptosis. In NOD/SCID mice bearing Hut-102 cell line xenografts, administration of LW-213 (10 mg/kg, ip, every other day for 4 weeks) markedly inhibited the growth of Hut-102 derived xenografts and prolonged survival. In conclusion, our study provides a new insight into the mechanism of LW-213-induced apoptosis, suggesting the potential of LW-213 as a promising agent against CTCL.


Assuntos
Antineoplásicos/farmacologia , Flavanonas/farmacologia , Linfoma Cutâneo de Células T/tratamento farmacológico , Neoplasias Cutâneas/tratamento farmacológico , Fator 4 Ativador da Transcrição/metabolismo , Animais , Antineoplásicos/administração & dosagem , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Relação Dose-Resposta a Droga , Fator de Iniciação 2 em Eucariotos/metabolismo , Feminino , Flavanonas/administração & dosagem , Flavanonas/química , Humanos , Concentração Inibidora 50 , Linfoma Cutâneo de Células T/patologia , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Espécies Reativas de Oxigênio/metabolismo , Neoplasias Cutâneas/patologia , Fator de Transcrição CHOP/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto , eIF-2 Quinase/metabolismo
8.
Scand J Immunol ; 91(2): e12841, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31833575

RESUMO

Tumour-associated macrophages (TAMs) comprise an important part of the tumour microenvironment and play a key role in malignant tumours progression. Tumour-derived extracellular vesicles (EVs) modulated TAMs polarization and reprogrammed TAMs to influence the progression of various tumours. Here, we hypothesized that diffuse large B cell lymphoma (DLBCL)-derived EVs can regulate macrophages polarization and thus contribute to tumour progression. Our results demonstrated that EVs, released from DLBCL, augment the M2 polarization effects of macrophages. Moreover, conditional medium derived from macrophages by DLBCL-derived EVs stimulation revealed the superior effects of promoting tumour proliferation, migration and invasion. Further analysis demonstrated that DLBCL-derived EVs regulated the metabolism of macrophages by increasing the expression of PGC-1ß protein, thereby reprogramming the macrophage phenotype of promoting tumour progression. In conclusion, our findings signify that the DLBCL-derived EVs mediated the increasing of functional PGC-1ß protein in macrophages to promote the tumour progression.


Assuntos
Vesículas Extracelulares/metabolismo , Linfoma Difuso de Grandes Células B/imunologia , Macrófagos/fisiologia , Proteínas de Ligação a RNA/metabolismo , Carcinogênese , Diferenciação Celular , Linhagem Celular Tumoral , Proliferação de Células , Reprogramação Celular , Meios de Cultivo Condicionados , Progressão da Doença , Humanos , Ativação de Macrófagos , MicroRNAs/genética , Fenótipo , Microambiente Tumoral , Regulação para Cima
9.
Pharmacol Res ; 159: 104961, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32474086

RESUMO

Cardiovascular diseases are recognized to be a major cause of people morbidity and mortality. A host of stress signals contribute to the pathogenesis of cardiovascular disorders. Deficiency of hydrogen sulfide (H2S) or nitric oxide (NO) coordinately plays essential roles in the development of cardiovascular diseases. Recent studies have shown that interaction between the two gaseostransmitters, H2S and NO, may give rise to nitroxyl (HNO), one-electron-reduced product of NO. HNO is found to exhibit a variety of biological and pharmacological properties including positive inotropy and cardiovascular protective effects, etc. In this review, recent progresses regarding HNO generation, detection, biochemical and pharmacological functions are discussed.


Assuntos
Fármacos Cardiovasculares/uso terapêutico , Doenças Cardiovasculares/tratamento farmacológico , Sistema Cardiovascular/efeitos dos fármacos , Óxidos de Nitrogênio/uso terapêutico , Animais , Fármacos Cardiovasculares/efeitos adversos , Doenças Cardiovasculares/metabolismo , Doenças Cardiovasculares/fisiopatologia , Sistema Cardiovascular/metabolismo , Sistema Cardiovascular/fisiopatologia , Humanos , Sulfeto de Hidrogênio/metabolismo , Óxido Nítrico/metabolismo , Doadores de Óxido Nítrico/uso terapêutico , Óxidos de Nitrogênio/efeitos adversos , Óxidos de Nitrogênio/metabolismo
10.
Acta Pharmacol Sin ; 41(2): 249-259, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31316178

RESUMO

Chronic myeloid leukemia (CML) is a clonal hematopoietic stem cell neoplasm characterized by an uncontrolled proliferation of moderately and well differentiated cells of the granulocytic lineage. LW-213, a newly synthesized flavonoid compound, was found to exert antitumor effects against breast cancer through inducing G2/M phase arrest. We investigated whether LW-213 exerted anti-CML effects and the underlying mechanisms. We showed that LW-213 inhibited the growth of human CML cell lines K562 and imatinid-resistant K562 (K562r) in dose- and time-dependent manners with IC50 values at the low µmol/L levels. LW-213 (5, 10, 15 µM) caused G2/M phase arrest of K562 and K562r cells via reducing the activity of G2/M phase transition-related proteins Cyclin B1/CDC2 complex. LW-213 treatment induced apoptosis of K562 and K562r cells via inhibiting the expression of CDK9 through lysosome degradation, thus leading to the suppression of RNAPII phosphorylation, down-regulation of a short-lived anti-apoptic protein MCL-1. The lysosome inhibitor, NH4Cl, could reverse the anti-CML effects of LW-213 including CDK9 degradation and apoptosis. LW-213 treatment also degraded the downstream proteins of BCR-ABL1, such as oncoproteins AKT, STAT3/5 in CML cells, which was blocked by NH4Cl. In primary CML cells and CD34+ stem cells, LW-213 maintained its pro-apoptotic activity. In a K562 cells-bearing mice model, administration of LW-213 (2.5, 5.0 mg/kg, ip, every other day for 4 weeks) dose-dependently prolonged the survival duration, and significantly suppressed huCD45+ cell infiltration and expression of MCL-1 in spleens. Taken together, our results demonstrate that LW-213 may be an efficient agent for CML treatment.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Flavonoides/farmacologia , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Animais , Antineoplásicos/administração & dosagem , Relação Dose-Resposta a Droga , Resistencia a Medicamentos Antineoplásicos , Feminino , Flavonoides/administração & dosagem , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Humanos , Mesilato de Imatinib/farmacologia , Concentração Inibidora 50 , Células K562 , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Pontos de Checagem da Fase M do Ciclo Celular/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Fatores de Tempo
11.
Arch Toxicol ; 94(1): 305-323, 2020 01.
Artigo em Inglês | MEDLINE | ID: mdl-31760435

RESUMO

Mitotic catastrophe of cancer cells induced by drugs is characterized by low dosage and low toxicity, representing a significant advantage in the cancer treatment. Effective therapeutic options are limited for T-cell malignancies patients who are still treated by high-dose multiagent chemotherapy, potentially followed by hematopoietic stem cell transplantation, highlighting the urgency for identification of more effective anti-T-cell malignancies drugs. The use of antineoplastic drugs which induced tumor cell mitotic catastrophe would be a new strategy for cancer therapy. Nevertheless, there is still no effective mitotic catastrophe agent in T-cell malignancies. Our study showed that nonlethal dosage (ND) of GL-V9 (5-hydroxy-8-methoxy-2-phenyl-7-(4-(pyrrolidin-1-yl) butoxy) 4 H-chromen-4-one) (2 µM), a potential anticancer drug, not only attenuated cell growth and survival, but also arrested the cell cycle in G2/M phase and induced multipolar spindles, nuclear alterations (micronucleation and multinucleation), which are the most prominent morphological characteristics of mitotic catastrophe, in T-cell malignancies cell lines including Jurkat, HuT-102, and HuT-78. Moreover, ND GL-V9 could trigger DNA damage, and significantly influence several mitosis-associated proteins. Besides, results showed that ND GL-V9 increased the activity of senescence-associated ß-galactosidase (SA-ß-Gal) following the induction of mitotic catastrophe in Jurkat and HuT-102 cells with intact p53, while causing apoptosis in p53-deficient HuT-78 cells. We concluded that the anti-T-cell malignancies effects of ND GL-V9 and clarified the precise regulation in the process of mitosis under the action of GL-V9 in T-cell malignancies. Our data provided new evidence for the study of T-cell malignancies treatment associated with mitotic catastrophe and cellular senescence induction.


Assuntos
Antineoplásicos/farmacologia , Flavonoides/farmacologia , Linfoma/tratamento farmacológico , Mitose/efeitos dos fármacos , Linfócitos T/efeitos dos fármacos , Apoptose/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Senescência Celular/efeitos dos fármacos , Humanos , Células Jurkat , Linfoma/patologia , Linfócitos T/patologia , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
12.
J Environ Manage ; 260: 109923, 2020 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-32090794

RESUMO

Eutrophication and associated algal blooms are principal environmental challenges confronting lakes in China, particularly in the Eastern Plains ecoregion. The empirical relationships between nutrient and chlorophyll a (Chla) level and Secchi depth (SD) are widely used as a theoretical basis for lake eutrophication management. However, these relationships are largely influenced by hydromorphological conditions and biogeochemical processes. Thus, there is a need to establish a type-specific understanding of these interactions. In the current study, lakes in the Chinese Eastern Plains ecoregion were subdivided into four lake types according to water retention time (LRT), water depth, and water area. Regression analyses indicated that the impacts of nutrient (total nitrogen, TN; total phosphorus, TP) concentrations on summer Chla were significantly reduced in lakes with high inorganic suspended solids (ISS) (P<0.05). Meanwhile, the decrease in SD in these lakes were found to relate mainly to non-algal turbidity. In lakes characterized by both short LRT and high ISS content, the Chla exhibited limited response to nutrients. In contrast, in lakes with low ISS content and long LRT, the observed slopes of both Chla=f(TP) and SD=f(Chla) were significantly steeper (P < 0.05). The factors limiting summer algal growth and the development of type-specific nutrient criteria (TN and TP) of all four investigated lake types in the Eastern Plains ecoregion are discussed in the context of specific nutrients. Based on these results, we establish type-specific eutrophication assessment equations of TN, TP, Chla, and SD in our study lakes. Our results may provide essential information for achieving the cost-effective eutrophication management of lakes both in the Eastern Plains ecoregion and elsewhere with similar climatic and hydromorphological conditions. Moreover, we believe that the subdivision of lakes to allow type-specific eutrophication management framework may prove valuable for other ecoregions where the interpretation of empirical nutrient-Chla and SD relationships suffer from similar serious limitations.


Assuntos
Clorofila A , Lagos , China , Clorofila , Monitoramento Ambiental , Eutrofização , Nitrogênio , Nutrientes , Fósforo
13.
J Cell Mol Med ; 23(3): 1798-1812, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30565390

RESUMO

RD-N, an aminomethylated derivative of riccardin D, is a lysosomotropic agent that can trigger lysosomal membrane permeabilization followed by cathepsin B (CTSB)-dependent apoptosis in prostate cancer (PCa) cells, but the underlying mechanisms remain unknown. Here we show that RD-N treatment drives CTSB translocation from the lysosomes to the nucleus where it promotes DNA damage by suppression of the breast cancer 1 protein (BRCA1). Inhibition of CTSB activity with its specific inhibitors, or by CTSB-targeting siRNA or CTSB with enzyme-negative domain attenuated activation of BRCA1 and DNA damage induced by RD-N. Conversely, CTSB overexpression resulted in inhibition of BRCA1 and sensitized PCa cells to RD-N-induced cell death. Furthermore, RD-N-induced cell death was exacerbated in BRCA1-deficient cancer cells. We also demonstrated that CTSB/BRCA1-dependent DNA damage was critical for RD-N, but not for etoposide, reinforcing the importance of CTSB/BRCA1 in RD-N-mediated cell death. In addition, RD-N synergistically increased cell sensitivity to cisplatin, and this effect was more evidenced in BRCA1-deficient cancer cells. This study reveals a novel molecular mechanism that RD-N promotes CTSB-dependent DNA damage by the suppression of BRCA1 in PCa cells, leading to the identification of a potential compound that target lysosomes for cancer treatment.


Assuntos
Aminas/química , Proteína BRCA1/metabolismo , Catepsina B/metabolismo , Dano ao DNA/efeitos dos fármacos , Lisossomos/efeitos dos fármacos , Éteres Fenílicos/farmacologia , Neoplasias da Próstata/patologia , Estilbenos/farmacologia , Apoptose/efeitos dos fármacos , Proteína BRCA1/genética , Catepsina B/genética , Permeabilidade da Membrana Celular/efeitos dos fármacos , Humanos , Lisossomos/metabolismo , Masculino , Metilação , Éteres Fenílicos/química , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Proteólise , Estilbenos/química , Células Tumorais Cultivadas
14.
Ann Hum Genet ; 83(5): 299-309, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31222730

RESUMO

BACKGROUND: The association between interleukin-10 (IL-10)-1082 (-1087) A > G polymorphism and either chronic (CP) or aggressive periodontitis (AgP) susceptibility was conflicting. This meta-analysis aimed to quantitatively estimate the association. METHODS: Pubmed, Embase, Web of Science, and WANFAN databases were searched for relevant studies that were submitted prior to January 31, 2018, and meta-analyses were performed using STATA 14.0. RESULTS: Database mining yielded 26 studies of interest. For the IL-10-1082 (-1087) A > G (rs1800896) polymorphism and its relation to CP susceptibility, the overall analysis showed no significant estimates, but subgroup analysis revealed significant associations in the AA versus GG + GA model in the Caucasian population (odds ratio [OR] = 1.274, 95% confidence interval [CI] = 1.069-1.518, P = 0.007; I2  = 0.0%, P = 0.483) and in the GG versus AA + AG model in the Han population (OR = 6.66, 95% CI = 7.72-9.41, P = 0.000; I2  = 0.0%, P = 0.82), which all showed no obvious publication bias by Egger's linear regression test. For the association between an IL-10-1082 (-1087) A > G polymorphism and AgP susceptibility, the overall analysis and Caucasian subgroup analysis yielded nonsignificant estimates. CONCLUSIONS: Our meta-analysis indicated that the IL-10-1082 (-1087) AA genotype in the Caucasian population, and the GG genotype in the Han population might be putative risk factors for CP. PRACTICAL IMPLICATIONS: The IL-10-1082 (-1087) AA genotype and the GG genotype might be potential biomarkers for Caucasian CP and for Han CP, respectively. However, additional research will be required to validate the findings of this meta-analysis.


Assuntos
Predisposição Genética para Doença , Interleucina-10/genética , Periodontite/genética , Povo Asiático/genética , Humanos , Razão de Chances , Polimorfismo de Nucleotídeo Único , População Branca/genética
15.
J Environ Manage ; 233: 499-512, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30594115

RESUMO

Due to rapid urbanization and modernization, the construction sector now generates one third of all greenhouse gas emissions in China. Using an equilibrium strategy combined with the carbon allowance allocation, this study presents a synergistic Stackelberg model based on a construction project planning framework to deal with cumulative CO2 emissions. The bi-level model simultaneously considers the sequential decision-making relationship between the authority (leader) and the enterprises' interactive objectives and constraints. Unlike previous research, this bi-level model gives a holistic analysis of the interactivity of multiple stakeholders, thereby enabling the inherent conflicts and equilibrium between environmental protection and decision makers' profits to be reconciled and balanced. To deal with the bi-level model complexity, an interactive solution method that integrates an evolutionary mechanism and improved particle swarm optimization (IPSO) is designed for solving a construction supply planning problem. The robustness and practicality of the proposed methodology are then validated in a real world case, and sensitivity analyses under different carbon emissions quotas are also given. The results indicate that the methodology can systematically reduce carbon emissions in the Chinese construction sector, and when the authority has a strict emissions reduction altitude, construction practitioners are able to attain high carbon efficiencies; therefore, the model provides valuable strategy guidance for policymakers and business executives.


Assuntos
Carbono , Conservação dos Recursos Naturais , China , Comércio
16.
Molecules ; 24(15)2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31390847

RESUMO

Diabetic kidney disease develops in approximately 40% of diabetic patients and is a major cause of chronic kidney diseases (CKD) and end stage kidney disease (ESKD) worldwide. Hydrogen sulfide (H2S), the third gasotransmitter after nitric oxide (NO) and carbon monoxide (CO), is synthesized in nearly all organs, including the kidney. Though studies on H2S regulation of renal physiology and pathophysiology are still in its infancy, emerging evidence shows that H2S production by renal cells is reduced under disease states and H2S donors ameliorate kidney injury. Specifically, aberrant H2S level is implicated in various renal pathological conditions including diabetic nephropathy. This review presents the roles of H2S in diabetic renal disease and the underlying mechanisms for the protective effects of H2S against diabetic renal damage. H2S may serve as fundamental strategies to treat diabetic kidney disease. These H2S treatment modalities include precursors for H2S synthesis, H2S donors, and natural plant-derived compounds. Despite accumulating evidence from experimental studies suggests the potential role of the H2S signaling pathway in the treatment of diabetic nephropathy, these results need further clinical translation. Expanding understanding of H2S in the kidney may be vital to translate H2S to be a novel therapy for diabetic renal disease.


Assuntos
Sulfeto de Hidrogênio/metabolismo , Animais , Nefropatias Diabéticas/tratamento farmacológico , Nefropatias Diabéticas/etiologia , Nefropatias Diabéticas/metabolismo , Nefropatias Diabéticas/patologia , Avaliação Pré-Clínica de Medicamentos , Fibrose , Humanos , Sulfeto de Hidrogênio/química , Sulfeto de Hidrogênio/farmacologia , Sulfeto de Hidrogênio/uso terapêutico , Glomérulos Renais/efeitos dos fármacos , Glomérulos Renais/metabolismo , Glomérulos Renais/patologia , Redes e Vias Metabólicas/efeitos dos fármacos , Óxido Nítrico/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/metabolismo , Podócitos/metabolismo , Podócitos/patologia , Sistema Renina-Angiotensina
17.
Mol Cell Biochem ; 441(1-2): 191-199, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28875388

RESUMO

IgA nephropathy (IgAN), the most common glomerulonephritis, has an unclear pathogenesis. The role of Th22 cells, which are intimately related to proteinuria and progression in IgAN, in mediating infection-related IgAN is unclear. This study aimed to characterize the association between intrinsic renal cells (tubular epithelial cells and mesangial cells) and Th22 cells in immune regulation of infection-related IgAN and to elucidate the impact of Th22 lymphocytosis; the proinflammatory cytokines IL-1, IL-6, and TNF-α; and CCL chemokines on kidney fibrosis. Hemolytic streptococcus infection induced an increase in IL-1, IL-6, and TNF-α, resulting in Th22 cell differentiation from T lymphocytes obtained from patients with IgAN, and the CCL20-CCR6, CCL22-CCR4, and/or CCL27-CCR10 axes facilitated Th22 cell chemotaxis. The increased amount of Th22 cells caused an increase in TGF-ß1 levels, and anti-CD80, anti-CD86, and CTLA-4Ig treatment reduced TGF-ß1 levels by inhibiting Th22 lymphocytosis and secretion of cytokines and chemokines, thus potentially relieving kidney fibrosis. Our data suggest that Th22 cells might be recruited into the kidneys via the CCL20-CCR6, CCL22-CCR4, and/or CCL27-CCR10 axes by mesangial cells and tubular epithelial cells in infection-related IgAN. Th22 cell overrepresentation was attributed to stimulation of the B7-CTLA-4Ig antigen-presenting pathway and IL-1, IL-6, and TNF-α.


Assuntos
Antígeno B7-1/imunologia , Antígeno CTLA-4/imunologia , Quimiocina CCL1/imunologia , Glomerulonefrite por IGA/imunologia , Linfocitose/imunologia , Receptores CCR/imunologia , Transdução de Sinais/imunologia , Linfócitos T Auxiliares-Indutores/imunologia , Adolescente , Adulto , Feminino , Glomerulonefrite por IGA/patologia , Humanos , Linfocitose/patologia , Masculino , Pessoa de Meia-Idade , Linfócitos T Auxiliares-Indutores/patologia
19.
Ren Fail ; 40(1): 364-370, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29708439

RESUMO

The existing therapies of IgA nephropathy are unsatisfying. Acteoside, the main component of Rehmannia glutinosa with anti-inflammatory and anti-immune effects, can improve urinary protein excretion and immune disorder. Th22 cell is involved in IgA nephropathy progression. This study was determined to explore the effect of acteoside on mesangial injury underlying Th22 cell disorder in IgA nephropathy. Serum Th22 cells and urine total protein of patients with IgA nephropathy were measured before and after six months treatment of Rehmannia glutinosa acteoside or valsartan. Chemotactic assay and co-culture assay were performed to investigate the effect of acteoside on Th22 cell chemotaxis and differentiation. The expression of CCL20, CCL22 and CCL27 were analyzed. To explore the effect of acteoside on mesangial cell injury induced by inflammation, IL-1, IL-6, TNF-α and TGF-ß1 were tested. Results showed that the proteinuria and Th22 lymphocytosis of patients with IgA nephropathy significantly improved after combination treatment of Rehmannia glutinosa acteoside and valsartan, compared with valsartan monotherapy. In vitro study further demonstrated that acteoside inhibit Th22 cell chemotaxis by suppressing the production of Th22 cell attractive chemokines, i.e., CCL20, CCL22 and CCL27. In addition, acteoside inhibited the Th22 cell proliferation. Co-culture assay proved that acteoside could relieve the overexpression of pro-inflammatory cytokines, and prevent the synthesis of TGF-ß1. TGF-ß1 level in mesangial cells was positively correlated with the Th22 cell. This research demonstrated that acteoside can alleviate mesangial cell inflammatory injury by modulating Th22 lymphocytes chemotaxis and proliferation.


Assuntos
Glomerulonefrite por IGA/tratamento farmacológico , Glucosídeos/farmacologia , Imunossupressores/farmacologia , Células Mesangiais/efeitos dos fármacos , Fenóis/farmacologia , Linfócitos T Auxiliares-Indutores/efeitos dos fármacos , Adulto , Biópsia , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Quimiocina CCL20/imunologia , Quimiocina CCL20/metabolismo , Quimiocina CCL22/imunologia , Quimiocina CCL22/metabolismo , Quimiocina CCL27/imunologia , Quimiocina CCL27/metabolismo , Quimiotaxia/efeitos dos fármacos , Quimiotaxia/imunologia , Técnicas de Cocultura , Progressão da Doença , Quimioterapia Combinada/métodos , Feminino , Glomerulonefrite por IGA/imunologia , Glomerulonefrite por IGA/patologia , Glucosídeos/uso terapêutico , Humanos , Imunossupressores/uso terapêutico , Masculino , Células Mesangiais/imunologia , Células Mesangiais/patologia , Pessoa de Meia-Idade , Fenóis/uso terapêutico , Proteinúria/tratamento farmacológico , Rehmannia/química , Linfócitos T Auxiliares-Indutores/imunologia , Linfócitos T Auxiliares-Indutores/metabolismo , Fator de Crescimento Transformador beta1/imunologia , Fator de Crescimento Transformador beta1/metabolismo , Resultado do Tratamento , Valsartana/uso terapêutico , Adulto Jovem
20.
Molecules ; 23(4)2018 04 17.
Artigo em Inglês | MEDLINE | ID: mdl-29673187

RESUMO

The FAD8 gene catalyzes the conversion of diene fatty acids to triene fatty acids and is a key enzyme that determines the synthesis of alpha-linolenic acid. In this study, the full-length cDNAs of FAD8-1, FAD8-2, and FAD8-3 are cloned from Paeonia ostii T. Hong & J. X. Zhang and named as PoFAD8-1, PoFAD8-2, and PoFAD8-3. Their open reading frame is 1203 bp, 1152 bp, and 1353 bp which encoded 400, 371, and 450 amino acids. The molecular weights of the amino acids are 46 kDa, 43 kDa, and 51 kDa while the isoelectric points are 7.34, 8.74, and 9.23, respectively. Bioinformatics analysis shows that all three genes are hydrophobic-hydrophobic, PoFAD8-1 has three transmembrane domains, and PoFAD8-2 and PoFAD8-3 have two transmembrane domains. Multiple series alignment and phylogenetic analysis revealed that PoFAD8-1 and PoFAD8-2 are closely related while PoFAD8-3 is more closely related to Paeonia delavayi. Subcellular localization results showed that PoFAD8-1 was located on the ER membrane and PoFAD8-2 and PoFAD8-3 were located on the chloroplast membrane. The relative expression level of PoFAD8-1 in seeds is very high. PoFAD8-2 expressed more in the ovary than the other two genes. PoFAD8-3 was highly expressed in roots, stems, leaves, petals, and ovaries.


Assuntos
Ácidos Graxos Dessaturases/metabolismo , Paeonia/enzimologia , Paeonia/metabolismo , Proteínas de Plantas/metabolismo , Sementes/enzimologia , Sementes/metabolismo , Ácidos Graxos Dessaturases/genética , Regulação da Expressão Gênica de Plantas/genética , Paeonia/genética , Proteínas de Plantas/genética , Reação em Cadeia da Polimerase em Tempo Real , Sementes/genética
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