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1.
Sci Total Environ ; 931: 172926, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697519

RESUMO

Flash droughts characterized by rapid onset and intensification are expected to be a new normal under climate change and potentially affect vegetation photosynthesis and terrestrial carbon sink. However, the effects of flash drought on vegetation photosynthesis and their potential dominant driving factors remain uncertain. Here, we quantify the susceptibility and response magnitude of vegetation photosynthesis to flash drought across different ecosystems (i.e., forest, shrubland, grassland, and cropland) in China based on reanalysis and satellite observations. By employing the extreme gradient boosting model, we also identify the dominant factors that influence these flash drought-photosynthesis relationships. We show that over 51.46 % of ecosystems across China are susceptible to flash drought, and grasslands are substantially suppressed, as reflected in both sensitivity and response magnitude (with median gross primary productivity anomalies of -0.13). We further demonstrate that background climate differences (e.g., mean annual temperature and aridity) predominantly regulate the response variation in forest and shrubland, with hotter/colder or drier ecosystems being more severely suppressed by flash drought. However, in grasslands and croplands, the differential vegetation responses are attributed to the intensity of abnormal hydro-meteorological conditions during flash drought (e.g., vapor pressure deficit (VPD) and temperature anomalies). The effects of flash droughts intensify with increasing VPD and nonmonotonically relate to temperature, with colder or hotter temperatures leading to more severe vegetation loss. Our results identify the vulnerable ecological regions under flash drought and enable a better understanding of vegetation photosynthesis response to climate extremes, which may be useful for developing effective management strategies.


Assuntos
Mudança Climática , Secas , Ecossistema , Fotossíntese , China , Florestas
2.
Sci Total Environ ; 926: 172130, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38569962

RESUMO

Climate change has a discernible influence on rainfall patterns, thus potentially affecting the intricate dynamics of soil respiration (Rs) and soil carbon storage. However, we still lack a profound understanding of the determinants of Rs response to rainfall events. Here, utilizing a comprehensive 10-year dataset (2004-2013), we explored the direction and magnitude of Rs response to rainfall events and the underlying determinants in a temperate forest. Based on the identified 368 rainfall events over the study period, we demonstrate that rainfall suppresses Rs when the soil moisture is optimal and moist in the growing season, whereas its effect on Rs during the non-growing season is minimal. Notably, antecedent soil moisture, rather than rainfall amount, shows a substantial impact on Rs during the growing season (coefficient of determination (R2) = 0.37 for antecedent soil moisture, and R2 < 0.01 for rainfall amount). Incorporating antecedent soil moisture significantly enhances the explanatory power (R2) from 0.09 to 0.45 regarding the relative changes in Rs following rainfall events. Our results highlight the environmental dependency of Rs response to rainfall events and suggest that incorporating the role of antecedent soil moisture could enhance predictability and reduce uncertainty in ecosystem modeling.

3.
Thorax ; 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38388490

RESUMO

BACKGROUND: There is growing interest in the joint effects of hazardous trace elements (HTEs) on lung function deficits, but the data are limited. This is a critical research gap given increased global industrialisation. METHODS: A national cross-sectional study including spirometry was performed among 2112 adults across 11 provinces in China between 2020 and 2021. A total of 27 HTEs were quantified from urine samples. Generalised linear models and quantile-based g-computation were used to explore the individual and joint effects of urinary HTEs on lung function, respectively. RESULTS: Overall, there were negative associations between forced expiratory volume in 1 s (FEV1) and urinary arsenic (As) (z-score coefficient, -0.150; 95% CI, -0.262 to -0.038 per 1 ln-unit increase), barium (Ba) (-0.148, 95% CI: -0.258 to -0.039), cadmium (Cd) (-0.132, 95% CI: -0.236 to -0.028), thallium (Tl) (-0.137, 95% CI: -0.257 to -0.018), strontium (Sr) (-0.147, 95% CI: -0.273 to -0.022) and lead (Pb) (-0.121, 95% CI: -0.219 to -0.023). Similar results were observed for forced vital capacity (FVC) with urinary As, Ba and Pb and FEV1/FVC with titanium (Ti), As, Sr, Cd, Tl and Pb. We found borderline associations between the ln-quartile of joint HTEs and decreased FEV1 (-20 mL, 95% CI: -48 to +8) and FVC (-14 mL, 95% CI: -49 to+2). Ba and Ti were assigned the largest negative weights for FEV1 and FVC within the model, respectively. CONCLUSION: Our study investigating a wide range of HTEs in a highly polluted setting suggests that higher urinary HTE concentrations are associated with lower lung function, especially for emerging Ti and Ba, which need to be monitored or regulated to improve lung health.

4.
Anal Chem ; 95(25): 9453-9461, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-37310205

RESUMO

Nanotheranostic platforms integrated with diagnostic and therapeutic functions have been widely developed for tumor medicine. However, the "always-on" nanotheranostic platforms suffer from poor tumor specificity, which may largely restrict therapeutic efficacy and prevent precise theranostics. Here, we develop an in situ transformable pro-nanotheranostic platform (ZnS/Cu2O@ZIF-8@PVP) by encapsulating ZnS and Cu2O nanoparticles in a metal-organic framework (MOF) nanomaterial of ZIF-8 that allows activable photoacoustic (PA) imaging and synergistic photothermal/chemodynamic therapy (PTT/CDT) of tumors in vivo. It is shown that the pro-nanotheranostic platform gradually decomposes and releases ZnS nanoparticles and Cu+ ions in acidic conditions, which spontaneously trigger a cation exchange reaction and synthesize Cu2S nanodots in situ with activated PA signals and PTT effects. Moreover, the excessive Cu+ ions function as Fenton-like catalysts and catalyze the production of highly reactive hydroxyl radicals (•OH) for CDT using elevated levels of H2O2 in tumor microenvironments (TMEs). In vivo studies demonstrate that the in situ transformable pro-nanotheranostic platform can specifically image tumors via PA and photothermal imaging and efficiently ablate tumors through synergistic CDT/PTT. Our in situ transformable pro-nanotheranostic platform could provide a new arsenal for precise theranostics in cancer therapy.


Assuntos
Nanopartículas , Neoplasias , Técnicas Fotoacústicas , Humanos , Nanomedicina Teranóstica/métodos , Técnicas Fotoacústicas/métodos , Peróxido de Hidrogênio , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Nanopartículas/uso terapêutico , Linhagem Celular Tumoral , Microambiente Tumoral
5.
Virol Sin ; 38(3): 409-418, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37028598

RESUMO

Folate receptor alpha (FOLR1) is vital for cells ingesting folate (FA). FA plays an indispensable role in cell proliferation and survival. However, it is not clear whether the axis of FOLR1/FA has a similar function in viral replication. In this study, we used vesicular stomatitis virus (VSV) to investigate the relationship between FOLR1-mediated FA deficiency and viral replication, as well as the underlying mechanisms. We discovered that FOLR1 upregulation led to the deficiency of FA in HeLa cells and mice. Meanwhile, VSV replication was notably suppressed by FOLR1 overexpression, and this antiviral activity was related to FA deficiency. Mechanistically, FA deficiency mainly upregulated apolipoprotein B mRNA editing enzyme catalytic subunit 3B (APOBEC3B) expression, which suppressed VSV replication in vitro and in vivo. In addition, methotrexate (MTX), an FA metabolism inhibitor, effectively inhibited VSV replication by enhancing the expression of APOBEC3B in vitro and in vivo. Overall, our present study provided a new perspective for the role of FA metabolism in viral infections and highlights the potential of MTX as a broad-spectrum antiviral agent against RNA viruses.


Assuntos
Receptor 1 de Folato , Vírus da Estomatite Vesicular Indiana , Humanos , Animais , Camundongos , Células HeLa , Receptor 1 de Folato/farmacologia , Vírus da Estomatite Vesicular Indiana/genética , Antivirais/farmacologia , Replicação Viral , Ácido Fólico/farmacologia , Citidina Desaminase/genética , Antígenos de Histocompatibilidade Menor/genética , Antígenos de Histocompatibilidade Menor/farmacologia , Desaminases APOBEC
6.
ACS Nano ; 16(11): 19053-19066, 2022 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-36349982

RESUMO

The critical role of transition metal dyshomeostasis in Alzheimer's disease (AD) pathology poses demands of in vivo imaging for brain copper levels. Nanostructured probes afford prolonged retention time, increased accumulation, and enhanced photostability; however, their development for activatable photoacoustic (PA) imaging remains largely unexplored. We develop a principle of concept for activable PA imaging using in situ cation exchange of ultrathin zinc selenide (ZnSe) nanoplatelets for monitoring brain copper levels in AD mice. We start from quantitative modeling of optical absorption, time-resolved temperature field, and thermal expansion of copper selenide (CuSe) nanocrystals of different morphologies and reveal that ultrathin nanoplatelets afford substantial enhancement of near-infrared (NIR) absorption and PA pressures as compared to nanodots and nanoparticles. By tethering with a blood-brain barrier (BBB)-targeting peptide ligand, the ultrathin ZnSe nanoplatelet probe efficiently transports across the BBB and rapidly exchanges with endogenous copper ions, boosting activatable PA imaging of brain copper levels. We also demonstrate that the efficient exchange of ZnSe nanoplatelets with copper ions can reduce oxidative stress of neurons and protect neuronal cells from apoptosis. The nanoplatelet probe provides a paradigm for activatable PA imaging of brain copper levels, highlighting its potential for pathophysiologic study of AD.


Assuntos
Doença de Alzheimer , Técnicas Fotoacústicas , Animais , Camundongos , Cobre , Doença de Alzheimer/diagnóstico por imagem , Técnicas Fotoacústicas/métodos , Compostos de Zinco
7.
Chemosphere ; 290: 133360, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34929275

RESUMO

Organochlorine pesticide lindane in the environment and biota results in the potential risks on ecosystem and human health. Lindane can adversely affect the locomotion and nervous system, yet the potential neurotoxicity of lindane over generations remains uncertain. In this study, the neurotoxicity and underlying mechanisms in Caenorhabditis elegans (C. elegans) were investigated after parental (P0) exposure to lindane at environmentally relevant concentrations over generations. Exposure to lindane at concentrations of 10-100 ng/L significantly decreased body bends and head thrashes in P0 generation. Significant decrease of fluorescence labeled different neurotransmitters, and clear morphological changes by exposure to lindane at 10-100 ng/L suggested that lindane could induce the neuronal damage in C. elegans. During the transgenerational process, decreased locomotive behaviors were also observed in F1-F3 generations, and head thrashes returned to normal levels in F4 generation. Moreover, lindane exposure down-regulated the expression of dat-1, dop-1, glr-1 and mod-1genes, while up-regulated unc-30 gene in P0 generation, which recovered to normal levels in F4 generation. Interestingly, eat-4 continued to be regulated from inhibition to stimulation in P0-F4 generations, suggesting that glutamatergic transmission may more contribute to the neurotoxicity of lindane over generations.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Caenorhabditis elegans/genética , Proteínas de Caenorhabditis elegans/genética , Ecossistema , Hexaclorocicloexano/toxicidade , Humanos , Locomoção
8.
Sci Total Environ ; 791: 148097, 2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34412405

RESUMO

The Bohai Sea has recently suffered several seasonal oxygen-deficiency, even hypoxia events during the summer. To better understand effects of dissolved oxygen (DO) concentration on the bacterial composition in particle attached (PA) and free living (FL) fractions during the transition from oxic water to low oxygen conditions, the bacterial communities under three different oxygen levels, i.e., high oxygen (HO, close to 100% O2 saturation), medium oxygen (MO, close to 75% O2 saturation), and low oxygen (LO, close to 50% O2 saturation) in the Bohai Sea were investigated using 16S rRNA amplicon sequencing. Fourteen water samples from 5 stations were collected during a cruise from August to September in 2018. The results showed that the sequences of Proteobacteria and Actinobacteriota jointly accounted for up to 74% across all 14 samples. The Shannon index in HO samples were significantly higher than in LO samples (P < 0.05), especially in PA communities. The composition of bacterial communities varied by oxygen concentration in all samples, and the effect was more pronounced in the PA fraction, which indicates that the PA fraction was more sensitive to the change in oxygen concentration, possibly due to the tighter interactions in this community than in the FL fraction. This study provides novel insights into the distribution of bacterial communities, and clues for understanding the responses of bacterial communities in the Bohai Sea during the transition from the oxic to oxygen-deficient zones.


Assuntos
Bactérias , Água do Mar , Bactérias/genética , Humanos , Hipóxia , Oxigênio , Filogenia , RNA Ribossômico 16S/genética
9.
J Hazard Mater ; 403: 124036, 2021 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-33265051

RESUMO

Aquatic products are an important source of environmental pollutants to humans. This study was conducted to assess the bioaccessibility of selected brominated flame retardants and heavy metals in common aquatic products from the Pearl River Delta, South China, as well as associated human health risks. Based on a questionnaire survey, ten of the most consumed aquatic products were collected from local markets. The bioaccessibility of polybrominated diphenyl ethers (PBDEs), hexabromocyclododecane (HBCDDs), and heavy metals was assessed using an in vitro gastrointestinal model. Bioaccessibility of heavy metals (33.0-84.0%) and HBCDDs (38.5-68.4%) was significantly higher than that of PBDEs (13.4-65.4%). Total non-carcinogenic and carcinogenic risks from heavy metal consumption were much higher than the threshold values due to excessive abundances of arsenic in shellfish (HQ = 2.45, CR = 1.1 ×10-3). Furthermore, middle-aged populations and females were subjected to greater health risks due to different intakes of aquatic products among age and gender groups. Significant difference in bioaccessibility among analytes indicated that bioaccessibility of pollutants is non-negligible in health risk assessment. This is the first study systematically investigating health risks of aquatic products consumption and concludes that shellfish is a great cause for concern for the PRD residents.


Assuntos
Retardadores de Chama , Hidrocarbonetos Bromados , Metais Pesados , China , Monitoramento Ambiental , Feminino , Retardadores de Chama/análise , Éteres Difenil Halogenados/análise , Éteres Difenil Halogenados/toxicidade , Humanos , Hidrocarbonetos Bromados/análise , Metais Pesados/análise , Pessoa de Meia-Idade , Rios
10.
Environ Pollut ; 264: 114731, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32416425

RESUMO

Lindane, a lipophilic pollutant, may be toxic to organisms. To explore the toxic effects of lindane and the underlying mechanisms of this toxicity, the animal model Caenorhabditis elegans (C. elegans) was exposed to lindane for 3 d at environmentally relevant concentrations (0.01-100 ng/L) and the physiological, biochemical, and molecular indices were evaluated. Subacute exposure to 10-100 ng/L of lindane caused adverse physiological effects on the development, reproduction, and locomotion behaviors in C. elegans. Exposure to 1-100 ng/L of lindane increased the accumulation of Nile red and blue food dye, which suggested high permeability of the intestine in nematodes. Lindane exposure also significantly influenced the expression of genes related to intestinal development (e.g., mtm-6 and opt-2). Moreover, reactive oxygen species production, lipofuscin accumulation, and expression of oxidation resistance genes (e.g., sod-5 and isp-1) were significantly increased in C. elegans exposed to 10-100 ng/L of lindane, which indicated that lindane exposure induced oxidative stress. According to Pearson correlation analyses, oxidative stress and intestinal damage were significantly correlated with the adverse physiological effects of lindane. Therefore, the adverse effects of lindane may have been induced by intestinal damage and oxidative stress, and mtm-6, opt-2, sod-5, isp-1, and mev-1 might play important roles in the toxicity of lindane.


Assuntos
Proteínas de Caenorhabditis elegans , Caenorhabditis elegans , Animais , Hexaclorocicloexano , Intestinos , Estresse Oxidativo , Espécies Reativas de Oxigênio
11.
Sci Total Environ ; 726: 138679, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32320865

RESUMO

To understand the toxicity and mechanism of polystyrene microplastics (PS-MPs) exposure, Caenorhabditis elegans (C. elegans) was exposed to various concentrations (0, 0.1, 1, 10, and 100 µg/L) of PS-MPs, and the levels physiological, biochemical, and molecular parameters were measured as endpoints. Subacute exposure to 1-100 µg/L of PS-MPs resulted in adverse physiological effects in C. elegans, and PS-MPs were ingested and accumulated in the intestine of C. elegans. Exposure to 100 µg/L of PS-MPs significantly increased reactive oxygen species (ROS) production, lipofuscin accumulation, and the expression oxidative stress-related genes, which suggests that PS-MPs exposure induced oxidative stress by ROS. In addition, exposure to 100 µg/L of PS-MPs caused a hyperpermeable state of the intestinal barrier and altered the expression of genes related to intestinal development, which indicates intestinal damage in C. elegans. According to Pearson correlation analyses, oxidative stress and intestinal damage were significantly correlated with adverse effects of PS-MPs in C. elegans. Therefore, it was speculated that the toxicity induced by PS-MPs resulted from the combination of oxidative stress and intestinal injury.


Assuntos
Caenorhabditis elegans , Poliestirenos , Animais , Microplásticos , Estresse Oxidativo , Plásticos , Espécies Reativas de Oxigênio
12.
Bioact Mater ; 5(2): 201-209, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32123773

RESUMO

Bacterial infection and related diseases are threatening the health of human beings. Photocatalytic disinfection as a simple and low-cost disinfection strategy is attracting more and more attention. In this work, TiO2 nanoparticles (NPs) were modified by co-doping of Ce and Er using the sol-gel method, which endowed TiO2 NPs with enhanced visible light photocatalytic performance but not pure ultraviolet photocatalytic properties compared the untreated TiO2. Our results disclosed that as the doping content of Er increased, the photocatalytic activity of modified TiO2 NPs initially increased and subsequently decreased. The same trend occurred for Ce doping. When the doping dose of Er and Ce is 0.5 mol% and 0.2 mol%, the 0.5Ce0.2Ti-O calcined at 800 °C presented the best antibacterial properties, with the antibacterial efficiency of 91.23% and 92.8% for Staphylococcus aureus and Escherichia coli, respectively. The existence of Er ions is thought to successfully turn the near-infrared radiation into visible region, which is easier to be absorbed by TiO2 NPs. Meanwhile, the addition of Ce ions can effectively extend spectral response range and inhibit the recombination of electrons and holes, enhancing the photocatalytic disinfection activity of co-doped TiO2.

13.
J Hazard Mater ; 393: 122423, 2020 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-32135368

RESUMO

As the environment deterioration is becoming more serious, bacterial pollution is threatening the health of human beings. Hence, it is vital to develop rapid and safe sterilization strategy. Herein, CuS/protonated g-C3N4(CuS/PCN) composites were synthesized by simple hydrothermal method and electrostatic adsorption. This heterostructured system exhibited enhanced photocatalytic properties under visible light compared with CuS or g-C3N4 alone, ascribing to the rapid separation of photogenerated electron-hole pairs. Meanwhile, the obvious photothermal effects of CuS/PCN were achieved and the temperature increased with the increased amount of CuS in the composites due to the more light absorption. However, when the CuS content is more than 10 %, photocurrent density is decreased with increasing the amount of CuS, indicating the increased recombination of photogenerated electron-hole pairs. When the CuS content is 20 %, the composite can perform the optimized synergistic effects of both photothermal action and photocatalysis under light irradiation for 20 min. The corresponding bacteria-killing efficiency against Staphylococcus aureus and Escherichia coli is 98.23 % and 99.16 %, respectively. The underlying mechanism is that the bacterial membrane can be weakened by reactive oxygen species and bacterial activities are inhibited by hyperthermia. This CuS/PCN heterojunction is promising for environmental disinfection including water and public facilities sterilization.


Assuntos
Antibacterianos/toxicidade , Cobre/toxicidade , Desinfecção/métodos , Escherichia coli/efeitos dos fármacos , Luz , Nitrilas/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Adsorção , Animais , Antibacterianos/química , Catálise , Sobrevivência Celular/efeitos dos fármacos , Cobre/química , Temperatura Alta , Camundongos , Células NIH 3T3 , Nitrilas/química , Processos Fotoquímicos , Eletricidade Estática
14.
J Hazard Mater ; 390: 122126, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32006853

RESUMO

Some new kinds of antibiotics-free antibacterial agents are required to deal with bacterial infections due to the occurrence of drug-resistance. In this work, Cu-based metal-organic framework (HKUST-1) embedded with CuS NPs were fabricated via a simple in-situ sulfuration process. The synthesized MOFs exhibited an highly effective disinfection efficacy of 99.70 % and 99.80 % against Staphylococcus aureus and Escherichia coli within 20 min irradiation of near-infrared (NIR) light, respectively, which was ascribed to the cooperative effects of photodynamic and photothermal effects of the composites. A certain amount of Cu2+ ions of the MOFs were reacted to form CuS NPs, which endowed this composite with outstanding photocatalytic and photothermal performance during NIR light irradiation. Moreover, HKUST-1 that composed of low toxic organic ligand 1,3,5-benzenetricarboxylic acid (H3BTC) coordinating copper ions could be a controllable carrier that imposed certain constraint on the NPs. Hence, these CuS@HKUST-1 would be a promising bioplatform for rapid bacteria-killing.


Assuntos
Cobre/efeitos da radiação , Escherichia coli/crescimento & desenvolvimento , Raios Infravermelhos , Estruturas Metalorgânicas/efeitos da radiação , Staphylococcus aureus/crescimento & desenvolvimento , Animais , Sobrevivência Celular , Cobre/química , Estruturas Metalorgânicas/química , Camundongos , Células NIH 3T3 , Esterilização/métodos
15.
Toxicol In Vitro ; 62: 104698, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31669364

RESUMO

Both PM2.5 and respiratory viruses are part of the atmospheric constituents. Respiratory viruses are often associated with PM2.5 exposure, but the mechanism of toxicity remains to be explored. The vitro models that adequately reproduce healthy cells or diseased cells exposing to PM2.5 and infecting VSV can provide a useful tool for studying innate immune mechanisms and investigating new therapeutic focus. In the environment of PM2.5, an infection model in which VSV infected A549 cells was established, that mimics the state in which the antiviral innate immune pathways are activated after the respiratory system is infected with RNA viruses. Subsequently, the model was exposed to PM2.5 for 24 h. PM2.5 could be ingested by A549 cells and synergize with VSV to inhibit cell viability and promote apoptosis. The expression of VSV-G were more abundant after VSV-infected A549 cells were exposed to PM2.5. Furthermore, PM2.5 inhibits VSV-induced IFN-ß expression in A549 cells. ISG15, CCL-5, and CXCL-10 had the same expression tendency with IFN-ß mRNA, consistently. Interestingly, when MG132 was applied, the expression of p-IRF-3 and IFN-ß proteins reduced by PM2.5 were refreshed. Conversely, the expression of VSV-G proteins were decreased. PM2.5 could degrade p-IRF-3 proteins by ubiquitination pathway to inhibit VSV-induced IFN-ß expression in A549 cells. Therefore, replication of the VSV viruses was promoted.


Assuntos
Poluentes Atmosféricos/toxicidade , Fator Regulador 3 de Interferon/metabolismo , Material Particulado/toxicidade , Ubiquitinação/efeitos dos fármacos , Vesiculovirus/efeitos dos fármacos , Células A549 , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Humanos , Fator Regulador 3 de Interferon/efeitos dos fármacos , Interferon beta/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Estomatite Vesicular/prevenção & controle , Estomatite Vesicular/virologia
16.
ACS Appl Mater Interfaces ; 12(1): 288-297, 2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31834761

RESUMO

Developing highly efficient chemodynamic therapy (CDT)-based theranostic technology for cancer treatment is highly desired but still challenging. A novel nanotheranostic platform is constructed for enhanced CDT by engineering hybrid CaO2 and Fe3O4 nanoparticles with a hyaluronate acid (HA) stabilizer and NIR fluorophore label. This design not only enables the nanotheranostic agent to afford highly efficient CDT against tumor cells but also confers NIR fluorescence (NIRF) and magnetic resonance (MR) bimodal imaging for in vivo visualization of CDT. Moreover, the use of the HA stabilizer allows for the facile synthesis of the nanotheranostic agent with excellent biocompatibility and active targetability. The nanotheranaostic agent possesses a high capacity of self-supplying H2O2 and producing •OH in acidic conditions, while retaining the desired stability under physiological conditions. It also demonstrates high selectivity to tumor cells via CDT with minimized toxicity to normal cells. In vivo studies reveal that our nanotheranaostic agent exhibits efficacious tumor growth inhibition via a CDT mechanism with favorable biosafety. Moreover, in vivo visualization of the CDT progress via NIRF and MR bimodal imaging demonstrates specific targeting and treatment of tumors. The developed H2O2 self-supplying, active targeting, and bimodal imaging nanotheranostic platform holds the potential as a highly efficient strategy for CDT of cancer.


Assuntos
Compostos de Cálcio , Óxido Ferroso-Férrico , Peróxido de Hidrogênio/metabolismo , Nanopartículas , Neoplasias Experimentais/tratamento farmacológico , Óxidos , Fotoquimioterapia , Animais , Compostos de Cálcio/química , Compostos de Cálcio/farmacologia , Linhagem Celular Tumoral , Óxido Ferroso-Férrico/química , Óxido Ferroso-Férrico/farmacologia , Camundongos , Camundongos Endogâmicos BALB C , Células NIH 3T3 , Nanopartículas/química , Nanopartículas/uso terapêutico , Neoplasias Experimentais/diagnóstico por imagem , Neoplasias Experimentais/metabolismo , Óxidos/química , Óxidos/farmacologia , Nanomedicina Teranóstica , Microambiente Tumoral/efeitos dos fármacos
17.
Front Genet ; 10: 1123, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31803230

RESUMO

A case-control study was used to explore the association between the methylation status in the promoter regions of the cGAS, MAVS, and TRAF3 genes and the diseases of cervical precancerous lesions (CPL) and cervical cancer (CC) in a Southern Chinese population, and to further explore their interaction effects with high-risk human papillomavirus (hrHPV) infection and environmental factors in these diseases. The study protocol was approved by the ethics committee of The First Affiliated Hospital of Jinan University, and this study was performed in 97 healthy controls, 75 patients with CPL and 33 patients with CC, while each participant has read and signed the informed consent forms before enrolment. The promoter methylation status genes were detected from the bisulfite-treated DNA by the bisulfite sequencing PCR (BSP) technique, which was carried out using MethPrimer. The cGAS, MAVS, and TRAF3 promoter methylation levels in CPL (CPL cGAS = 35.40%, CPL MAVS = 24.26%, and CPL TRAF3 = 96.76%) were significantly higher than those in the control (Control cGAS = 31.87%, Control MAVS = 21.16%, and Control TRAF3 = 96.26%, PcGAS < 0.001, PMAVS < 0.001, and PTRAF3 = 0.001); however, there was no significant differences between the CC and control. In the logistic regression model with adjusted covariates, compared with the individuals whose cGAS methylation levels were less than or equal to 31.87%, the women with the levels more than 31.87% increased the risk of CPL by 2.49 times (ORa = 2.49, 95% CI = 1.31-4.75, P a = 0.006). The women with MAVS methylation levels above 21.16% were 1.97 times more likely to have CPL than the those with the levels less than 21.16% (ORa = 1.97, 95% CI = 1.06-3.69, P a = 0.033). A synergistic interaction was found between hrHPV and gene promoter methylation levels of cGAS and MAVS in CPL; however, no potential interaction was observed in CC. The promoter methylation levels in cGAS, MAVS, and TRAF3 genes are higher in CPL than in control, indicating that hypermethylation might be an early event in the progression of cervical intraepithelial neoplasia (CIN). The interaction between the promoter methylation levels in cGAS and MAVS genes and hrHPV infection might play a role in the development of CPL.

19.
Environ Pollut ; 253: 909-917, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31351299

RESUMO

Tetrabromobisphenol A (TBBPA) is a nonregulated brominated flame retardant with a high production volume, and it is applied in a wide variety of consumer products. TBBPA is ubiquitous in abiotic matrices, wildlife and humans around the world. This paper critically reviews the published scientific data concerning the disposition, metabolism or kinetics and toxicity of TBBPA in animals and humans. TBBPA is rapidly absorbed and widely distributed among tissues, and is excreted primarily in the feces. In rats, TBBPA and its metabolites have limited systemic bioavailability. TBBPA has been detected in human milk in the general population. It is available to both the developing fetus and the nursing pups following maternal exposure. It has been suggested that TBBPA causes acute toxicity, endocrine disruptor activity, immunotoxicity, neurotoxicity, nephrotoxicity, and hepatotoxicity in animals. Cell-based assays have shown that TBBPA can induce reactive oxygen species in a concentration-dependent manner, and it promotes the production of inflammatory factors such as TNF α, IL-6, and IL-8. Cells exposed to high levels of TBBPA exhibit seriously injured mitochondria and a dilated smooth endoplasmic reticulum. This review will enhance the understanding of the potential risks of TBBPA exposure to ecological and human health.


Assuntos
Retardadores de Chama/toxicidade , Bifenil Polibromatos/toxicidade , Animais , Animais Selvagens , Disponibilidade Biológica , Fezes , Feminino , Retardadores de Chama/metabolismo , Halogenação , Humanos , Cinética , Masculino , Exposição Materna , Ratos
20.
Immunopharmacol Immunotoxicol ; 41(2): 199-206, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30724633

RESUMO

Objective: The industrial production and combustion of coal can produce silica nanoparticles (nano-SiO2). It enters the human body mainly through the respiratory tract and exerts a toxic effect. However, whether nano-SiO2 can increase the IL-1ß-induced inflammatory expression in A549 cells has not been tested. Therefore, the synergistic toxicity of nano-SiO2 and IL-1ß to A549 was observed in our study. Materials and methods: We exposed A549 cells to nano-SiO2 (0, 100, 500, and 1000 µg/ml) for 12 and 24 h. The effect of nano-SiO2 on the viability of A549 cells was observed by the CCK-8 method. The A549 cells were exposed to nano-SiO2 (1 mg/mL) and cytokine IL-1ß (10 ng/mL) for 4 h, and we detected the expression of IL-1ß and IL-6 cytokines by real time quantitative polymerase chain (RT-qPCR) and enzyme linked immunosorbent assay (ELISA). The expression of ß-Actin, I-κB, phospho-ERK1/2 (P-ERK1/2), total-ERK1/2 (T-ERK1/2), phospho-JNK (P-JNK), total-JNK (T-JNK), phospho-P38 (P-P38), and total-P38 (T-P38) in A549 cells was detected by the Western Blot method. Results: The nano-SiO2 treatment resulted in a time-dependent decrease in the viability of A549 cells. The synergistic effect of nano-SiO2 and IL-1ß was observed on the new production of IL-1ß and IL-6 in A549 cells. The Western blot results showed that nano-SiO2 can increase the expression of IL-1ß and IL-6 by promoting the phosphorylation of ERK1/2 and elevating the phosphorylation of I-κB by IL-1ß. IL-1ß and IL-6 were induced by nano-SiO2, and the IL-1ß treatment with 20 µM of I-κBα phosphorylation inhibitor (PD98059) and 20 µM of ERK1/2 inhibitor (BAY11-7082) for 1 h was significantly lower than that of the control group in A549 cells. Discussion and conclusion: These results indicated that nano-SiO2 had a toxic effect on A549 cells, and this effect could increase IL-1ß on the A549 cell-induced inflammatory response. The results suggested that the release of IL-1ß and IL-6 in A549 was enhanced by the synergistic IL-1ß-induced phosphorylation of ERK1/2 and I-κB. This process is similar to a snowball, and it is possible that IL-1ß is continuously produced and repeatedly superimposed in A549 cells to produce an inflammatory effect; then, a vicious circle occurs, and an inflammatory storm is accelerated.


Assuntos
Interleucina-1beta/toxicidade , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Nanopartículas/efeitos adversos , Dióxido de Silício/toxicidade , Células A549 , Humanos , Inflamação/induzido quimicamente , Inflamação/imunologia , Inflamação/patologia , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Sistema de Sinalização das MAP Quinases/imunologia , Proteína Quinase 1 Ativada por Mitógeno/imunologia , Proteína Quinase 3 Ativada por Mitógeno/imunologia , Fatores de Tempo
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