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1.
BMC Pregnancy Childbirth ; 24(1): 22, 2024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38172701

RESUMO

OBJECTIVE: To explore the feasibility of the golden-angle radial sparse parallel (GRASP) dynamic magnetic resonance imaging (MRI) technique in predicting the intraoperative bleeding risk of scar pregnancy. METHODS: A total of 49 patients with cesarean scar pregnancy (CSP) who underwent curettage and GRASP-MRI imaging were retrospectively selected between January 2021 and July 2022. The pharmacokinetic parameters, including Wash-in, Wash-out, time to peck (TTP), initial area under the curve (iAUC), the transfer rate constant (Ktrans), constant flow rate (Kep), and volume of extracellular space (Ve), were calculated. The amount of intraoperative bleeding was recorded by a gynecologist who performed surgery, after which patients were divided into non-hemorrhage (blood loss ≤ 200 mL) and hemorrhage (blood loss > 200 mL) groups. The measured pharmacokinetic parameters were statistically compared using the t-test or Mann-Whitney U test with a significant level set to be p < 0.05. The receiver operating characteristic (ROC) curve was constructed, and the area under the curve (AUC) was calculated to evaluate each parameter's capability in intraoperative hemorrhage subgroup classification. RESULTS: Twenty patients had intraoperative hemorrhage (blood loss > 200 mL) during curettage. The hemorrhage group had larger Wash-in, iAUC, Ktrans, Ve, and shorter TTP than the non-hemorrhage group (all P > 0.05). Wash-in had the highest AUC value (0.90), while Ktrans had the lowest value (0.67). Wash-out and Kep were not significantly different between the two groups. CONCLUSION: GRASP DCE-MRI has the potential to forecast intraoperative hemorrhage during curettage treatment of CSP, with Wash-in exhibiting the highest predictive performance. This data holds promise for advancing personalized treatment. However, further study is required to compare its effectiveness with other risk factors identified through anatomical MRI and ultrasound.


Assuntos
Cicatriz , Gravidez Ectópica , Gravidez , Feminino , Humanos , Estudos Retrospectivos , Cicatriz/diagnóstico por imagem , Cicatriz/etiologia , Cicatriz/cirurgia , Meios de Contraste , Imageamento por Ressonância Magnética/métodos , Gravidez Ectópica/diagnóstico por imagem , Gravidez Ectópica/etiologia , Gravidez Ectópica/cirurgia , Perda Sanguínea Cirúrgica , Curetagem
2.
Environ Sci Technol ; 57(9): 4039-4049, 2023 03 07.
Artigo em Inglês | MEDLINE | ID: mdl-36808991

RESUMO

Nitric oxide (NO) is an atmospheric pollutant and climate forcer as well as a key intermediary in the marine nitrogen cycle, but the ocean's NO contribution and production mechanisms remain unclear. Here, high-resolution NO observations were conducted simultaneously in the surface ocean and the lower atmosphere of the Yellow Sea and the East China Sea; moreover, NO production from photolysis and microbial processes was analyzed. The NO sea-air exchange showed uneven distributions (RSD = 349.1%) with an average flux of 5.3 ± 18.5 × 10-17 mol cm-2 s-1. In coastal waters where nitrite photolysis was the predominant source (89.0%), NO concentrations were remarkably higher (84.7%) than the overall average of the study area. The NO from archaeal nitrification accounted for 52.8% of all microbial production (11.0%). We also examined the relationship between gaseous NO and ozone which helped identify sources of atmospheric NO. The sea-to-air flux of NO in coastal waters was narrowed by contaminated air with elevated NO concentrations. These findings indicate that the emissions of NO from coastal waters, mainly controlled by reactive nitrogen inputs, will increase with the reduced terrestrial NO discharge.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Água do Mar , Óxido Nítrico , Poluentes Atmosféricos/análise , Oceanos e Mares , China , Monitoramento Ambiental
3.
Environ Res ; 238(Pt 1): 117110, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37696322

RESUMO

Understanding the control mechanisms of carbon dioxide (CO2) emissions in intertidal wetland sediments is beneficial for the concern of global carbon biogeochemistry and climate change. Nevertheless, multiple controls on CO2 emissions from intertidal wetland sediments to the atmosphere still need to be clarified. This study investigated the effect of tidal action on CO2 emissions from salt marsh sediments covered by Spartina alterniflora in the Jiaozhou Bay wetland using the static chamber method combined with an infrared CO2 detector. The results showed that the CO2 emission fluxes from the sediment during ebb tides were higher than those during flood tides. The whole wetland sediment acted as a weak source of atmospheric CO2 (average flux: 24.44 ± 16.80 mg C m-2 h-1) compared to terrestrial soils and was affected by the cycle of seawater inundation and exposure. The tidal influence on vertical dissolved inorganic carbon (DIC) transport in the sediment was also quantitated using a two-end member mixing model. The surface sediment layer (5-15 cm) with maximum DIC concentration during ebb tides became the one with minimum DIC concentration during flood tides, indicating the DIC transport from the surface sediment to seawater. Furthermore, aerobic respiration by microorganisms was the primary process of CO2 production in the sediment according to 16 S rDNA sequencing analysis. This study revealed the strong impact of tidal action on CO2 emissions from the wetland sediment and provided insights into the source-sink pattern of CO2 and DIC at the land-ocean interface.


Assuntos
Dióxido de Carbono , Áreas Alagadas , Dióxido de Carbono/análise , Metano/análise , Água do Mar , Solo/química
4.
Plant Foods Hum Nutr ; 78(4): 776-782, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37668768

RESUMO

Phytochemical investigation of 70% EtOH extract of the seeds of Capsella bursa-pastoris led to the isolation of a new cyclobutane organic acid (1), and fourteen known compounds, including two organosulfur compounds (2, 3), two quinonoids (4, 5), five flavonoids (6-10), three sterols (11-13) and two other types (14, 15). The structures of the compounds were elucidated by extensive spectroscopic analyses as well as comparison of their spectroscopic data with those reported in the literature. The antioxidant capacities of all compounds and extractive fractions were evaluated by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging test and ferric reducing antioxidant power (FRAP) assay. Then the antioxidative substances were evaluated for their neuroprotective effects against H2O2-induced HT22 cell injury. The results indicated the strong scavenging ability to free radical of the extractive fractions and compounds 1-3, 8-10 and 13, and the ferric reducing antioxidant power of the extractive fractions and compounds 1-3, 8 and 10, which were close to or higher than that of the positive control trolox. The EtOAc fraction, n-BuOH fraction, and compounds 1, 3 and 8 can protect HT-22 cells from oxidative damage.


Assuntos
Antioxidantes , Capsella , Antioxidantes/análise , Peróxido de Hidrogênio , Extratos Vegetais/química , Compostos Fitoquímicos/farmacologia , Sementes/química
5.
Environ Sci Technol ; 55(6): 3668-3675, 2021 03 16.
Artigo em Inglês | MEDLINE | ID: mdl-33620205

RESUMO

Nitric oxide (NO) is a short-lived intermediate of the oceanic nitrogen cycle, and it is produced by biological and photochemical processes in the ocean. Nitrogen dioxide (NO2) is a reactive atmospheric compound which has not been determined in the ocean so far. Here, we present the setup and validation of a novel continuous underway measurement system to measure dissolved NO and NO2 in the surface ocean. The system consists of a seawater/gas equilibration component coupled to a chemiluminescence detector. It was successfully deployed during a 12 day cruise to the East China Sea in May 2018. Dissolved NO and NO2 surface concentrations ranged from

Assuntos
Óxido Nítrico , Dióxido de Nitrogênio , China , Medições Luminescentes , Oceanos e Mares , Água do Mar
6.
Zhongguo Dang Dai Er Ke Za Zhi ; 23(4): 402-409, 2021 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-33840414

RESUMO

OBJECTIVE: To study the effect of astragaloside IV (AS-IV) on NOD-like receptor protein 3 (NLRP3) inflammasome in neonatal rats with hypoxic-ischemic brain damage (HIBD). METHODS: A total of 24 Sprague-Dawley rats, aged 7 days, were randomly divided into a sham-operation group, an HIBD group, and an AS-IV treatment group, with 8 rats in each group. After 24 hours of modeling, brain tissue was collected for hematoxylin-eosin staining, yo-PRO-1 staining, and EthD-2 immunofluorescent staining in order to observe the cerebral protection effect of AS-IV in vivo. HT22 cells were used to prepare a model of oxygen-glycogen deprivation (OGD), and a concentration gradient (50-400 µmol/L) was established for AS-IV. CCK-8 assay was used to measure the viability of HT22 cells. RT-PCR and Western blot were used to observe the effect of different concentrations of AS-IV on the mRNA and protein expression of NLRP3, gasdermin D (GSDMD), caspase-1, and interleukin-1ß (IL-1ß). RESULTS: Yo-Pro-1 and EthD-2 staining showed that compared with the sham-operation group, the HIBD group had an increase in pyroptotic cells with a small number of necrotic cells, and the AS-IV group had reductions in both pyroptotic and necrotic cells. Compared with the sham-operation group, the HIBD group had significantly higher protein expression levels of NLRP3, IL-1ß, caspase-1, and GSDMD (P < 0.05). Compared with the HIBD group, the AS-IV group had significant reductions in the protein expression levels of NLRP3, caspase-1, and GSDMD (P < 0.05). HT22 cell experiment showed that compared with the OGD group, the AS-IV group had inhibited mRNA and protein expression of NLRP3, GSDMD, caspase-1, and IL-1ß, with the best therapeutic effect at the concentration of 200 µmol/L (P < 0.05). CONCLUSIONS: AS-IV may alleviate HIBD in neonatal rats by inhibiting the expression of NLRP3, GSDMD, caspase-1, and IL-1ß.


Assuntos
Hipóxia-Isquemia Encefálica , Inflamassomos , Animais , Animais Recém-Nascidos , Encéfalo , Hipóxia-Isquemia Encefálica/tratamento farmacológico , Proteínas NLR , Ratos , Ratos Sprague-Dawley , Saponinas , Triterpenos
7.
Exp Parasitol ; 187: 59-66, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29496524

RESUMO

The aim of this study was to identify the biological characteristics and functions of a putative Trichinella spiralis glutathione S-transferase (TspGST). The results of real-time PCR and immunofluorescent test (IFT) showed that the TspGST gene was expressed at all of T. spiralis different developmental stages (muscle larvae, intestinal infective larvae, adult worms and newborn larvae). When anti-rTspGST serum, mouse infection serum, and pre-immune serum were added to the medium, the inhibition rate of the larvae penetrated into the intestinal epithelial cells (IECs) was 25.72%, 49.55%, and 4.51%, respectively (P < 0.01). The inhibition of anti-rTspGST serum on larval invasion of IECs was dose-dependent (P < 0.05). Anti-rTspGST antibodies killed T. spiralis newborn larvae by an ADCC-mediated mechanism. Our results showed that the TspGST seemed to be an indispensable protein for T. spiralis invasion, growth and survival in host.


Assuntos
Glutationa Transferase/metabolismo , Trichinella spiralis/enzimologia , Triquinelose/parasitologia , Animais , Western Blotting , Relação Dose-Resposta Imunológica , Feminino , Regulação Enzimológica da Expressão Gênica , Glutationa Transferase/genética , Glutationa Transferase/imunologia , Soros Imunes , Mucosa Intestinal/citologia , Mucosa Intestinal/parasitologia , Larva , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Proteínas Recombinantes/metabolismo , Organismos Livres de Patógenos Específicos , Suínos , Transcrição Gênica , Trichinella spiralis/genética , Trichinella spiralis/crescimento & desenvolvimento , Trichinella spiralis/imunologia
8.
Zhongguo Zhong Yao Za Zhi ; 42(4): 725-730, 2017 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-28959844

RESUMO

This study was aimed to explore the effects of Buzhong Yiqi decoction on the expression levels of Bad, NF-κB, caspase-9, Survivin, and mTOR in nude mice with A549/DDP transplantation tumors.Sixty BALB/C mice were randomly divided into blank control group, tumor-bearing control group, cisplatin group and Buzhong Yiqi decoction of high, medium and low doses+cisplatin groups (hereinafter referred to as the high,medium and low combined groups). A549/DDP cells (concentration of 5×106 cells/mL)were cultured and inoculated in various groups, then the tumor-forming situations were observed. Corresponding treatment was given in all groups. Fourteen days later, immunohistochemistry and Real-time PCR methods were used to detect the expression levels of Bad, NF-κB, caspase-9, Survivin, mTOR protein and mRNA in tumors.Results showed that Buzhong Yiqi decoction combined with cisplatin could reduce the volume of transplanted tumors, and there was significant difference between medium combined group and high combined group(P<0.05). As compared with the tumor-bearing control group, the expression levels of Bad, NF-κB, Survivin and mTOR were significantly reduced in medium and high combined groups(P<0.05); the protein and mRNA expression levels of caspase-9 were gradually increased in medium combined and high combined groups(P<0.05), with statistical difference with tumor-bearing control group(P<0.05). There were statistical difference in mRNA expression of Bad, NF-κB and caspase-9 between medium combined group, high combined group and cisplatin group, low-combined group, tumor-bearing control group(P<0.05), but there was no statistical difference between cisplatin group, low-combined group, and tumor-bearing control group. In addition, there was no statistical difference between medium combined group and high combined group in protein and mRNA expression levels of various factors. Experimental results showed that Buzhong Yiqi decoction combined with cisplatin can inhibit the growth of A549/DDP transplanted tumors, and the mechanism may be associated with regulating Bad, NF-κB, caspase-9, Survivin, and mTOR levels as well as promoting apoptosis.


Assuntos
Caspase 9/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Proteínas Inibidoras de Apoptose/metabolismo , NF-kappa B/metabolismo , Proteínas Repressoras/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Proteína de Morte Celular Associada a bcl/metabolismo , Células A549 , Animais , Antineoplásicos , Apoptose , Cisplatino/farmacologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Transplante de Neoplasias , Survivina
9.
Parasitol Res ; 115(2): 615-22, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-26468148

RESUMO

The excretory-secretory (ES) antigens from Trichinella spiralis muscle larvae are the most commonly used diagnostic antigens for trichinellosis, but specific IgG antibodies were not detected in early stage of infection. The aim of this study was to identify early diagnostic antigens from ES proteins of intestinal infective larvae (IIL), the first invasive stage of T. spiralis. Six bands (92, 52, 45, 35, 32, and 29 kDa) of IIL ES proteins were recognized by infection sera in Western blotting as early as 10 days post infection. Total of 54 T. spiralis proteins in six bands were identified by shotgun LC-MS/MS, 30 proteins were annotated, and 27 had hydrolase activity. Several proteins (serine protease, putative trypsin, deoxyribonuclease II family protein, etc.) could be considered as the potential early diagnostic antigens for trichinellosis. Our study provides new insights for screening early diagnostic antigens from intestinal worms of T. spiralis.


Assuntos
Antígenos de Helmintos/imunologia , Proteínas de Helminto/imunologia , Proteômica , Trichinella spiralis/imunologia , Triquinelose/diagnóstico , Animais , Anticorpos Anti-Helmínticos/sangue , Western Blotting , Eletroforese em Gel de Poliacrilamida , Cromatografia Gasosa-Espectrometria de Massas , Proteínas de Helminto/metabolismo , Larva/imunologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Músculos/metabolismo , Músculos/parasitologia , Serina Proteases/imunologia , Organismos Livres de Patógenos Específicos , Suínos , Triquinelose/imunologia
10.
Nitric Oxide ; 42: 54-61, 2014 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-25218514

RESUMO

Dimethylsulfoniopropionate (DMSP) and nitric oxide (NO) in marine microalgae are considered as two important compounds involved in a variety of physiological functions. We examined the NO responses and the growth of Isochrysis galbana Parke and Gymnodinium sp. when supplemented with different concentrations of DMSP solutions in the cultures. Production of DMSP and dimethylsulfide (DMS) in Amphidinium carterae and Emiliania Huxleyi was investigated after the addition of NO donor sodium nitroprusside (SNP) and NO solution to algal media. The release peaks of NO were observed in cell suspensions of I. galbana Parke and Gymnodinium sp. immediately after the injection of DMSP solutions. The growth of these two microalgae was found to be significantly promoted or inhibited caused by exogenous DMSP. There was a decrease of DMSP concentrations in algal cultures within 24 h, accompanied with an increase in DMS, due to the effect of NO. The results provided direct evidence to confirm that there exist mutual effects of DMSP and NO during the growth of marine microalgae, which is speculated to be related to their roles as signaling molecules in planktonic communities.


Assuntos
Biologia Marinha , Microalgas/crescimento & desenvolvimento , Óxido Nítrico/farmacologia , Compostos de Sulfônio/farmacologia
11.
Zhongguo Zhong Xi Yi Jie He Za Zhi ; 34(10): 1250-5, 2014 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-25509271

RESUMO

OBJECTIVE: To analyze the reversal effect of Buzhong Yiqi Decoction (BYD) on multidrug resistance of human adenocarcinoma of lung cell line A549/DDP, and to study its effect on the expression of survivin by using serum pharmacological methods in vitro. Methods Totally 24 SD rats were divided into the high, medium and low dose groups, and the blank control group by randomized controlled method. The high dose BYD containing serum (1. 134 g/mL, 2 mL), the middle dose BYD containing serum (0.576 g/mL, 2 mL), and the low dose BYD containing serum (0.284 g/mL, 2 mL) were prepared. The inhibitory effects of different dose and concentrations BYD on the proliferation of A549 and A549/DDP cells were detected by MTT assay, and the drug resistance reversal fold was calculated. The expression of Survivin in the two cell strains were detected respectively by immunohistochemical assay, Western blot, and immunofluorescence method. RESULTS: BYD containing serum showed obvious inhibitory effect on the growth of A549 and 549/DDP. The inhibition rates of 10% dose groups were higher than those of 5% dose groups. Besides, it gradually increased along with increased concentrations. Compared with 10% blank control group, the inhibition rate increased in 10% middle and low dose groups (P <0.05). After acted with 10% middle dose BYD containing serum, IC50, of A549 and A549/DDP were both reduced (P <0.05), reversal fold (RF) both increased. Its reversal ratio on A549/DDP cells was 2. 46, decreasing the resistance of A549/DDP to DDP. Compared with A549 in the same group, the expression of Survivin was detected to decrease by immunocytochemical assay, Western blot, and immunofluorescence method (P<0.05). Compared with 10% blank control group, the inhibition rate decreased in 10% middle dose group (P <0. 05). CONCLUSIONS: 10% middle dose BYD containing serum could significantly inhibit the apoptosis of A549 and A549/DDP. Besides, it could moderately reverse the multidrug resistance of A549/DDP cells to DDP possibly through reducing the intracellular expression of Survivin and enhancing the sensitivity 549/DDP to chemotherapeutics.


Assuntos
Adenocarcinoma/metabolismo , Cisplatino/farmacologia , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias Pulmonares/metabolismo , Adenocarcinoma de Pulmão , Animais , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Proteínas Inibidoras de Apoptose/metabolismo , Proteínas Associadas aos Microtúbulos/farmacologia , Ratos
12.
Zhongguo Zhong Yao Za Zhi ; 39(10): 1869-73, 2014 May.
Artigo em Chinês | MEDLINE | ID: mdl-25282897

RESUMO

OBJECTIVE: To explore the effect of Buzhong Yiqi decoction on PI3K/AKT signaling pathway in spleen, stomach and lung of nude mice with lung adenocarcinoma transplantation tumor. METHOD: Totally 60 nude mice were randomly divided into the blank control group, the tumor-bearing control group, the cisplatin group, the low-dose Buzhong Yiqi decoction group, the middle-dose Buzhong Yiqi decoction group and the high-dose Buzhong Yiqi decoction group. After the corresponding interventions, efforts were made to measure the transplanted tumor volume and calculate the tumor inhibiting rate. The immunohistochemical method and real time PCR were used to detect the expression of PI3K and AKT level in nude mice spleen, stomach and lung. RESULT: Buzhong Yiqi decoction of different concentrations combined with cisplatin could inhibit the growth of the transplanted tumor, with the strongest inhibitory effect in the middle-dose Buzhong Yiqi decoction group and the high-dose Buzhong Yiqi decoction group. All of the expressions of PI3K and AKT protein and gene in the spleen, stomach and lung increased, with the most significant increase in the tumor-bearing group. Along with the increase of the concentration of cisplatin and Buzhong Yiqi decoction, the expressions of PI3K and AKT gradually reduced. Compared with the tumor-bearing control group, there were statistical differences in spleen and stomach tissues (P < 0.05). Compared with the cisplatin group, the middle-dose Buzhong Yiqi decoction group and the high-dose Buzhong Yiqi decoction group showed statistical differences (P < 0.05), but without statistical difference compared with the blank control group. CONCLUSION: Among nude mice with lung adenocarcinoma transplantation tumor, the PI3K and AKT protein and gene expressions in spleen, stomach and lung tissues increased, which might indicated the effect of cisplatin and Buzhong Yiqi decoction in reducing PI3K and AKT expressions and the relations between the reduction degree and the concentrations of Buzhong Yiqi decoction. Cisplatin combined with Buzhong Yiqi decoction could decrease the PI3K and AKT protein and gene expression in spleen, stomach and lung, and make the pathway closer to normal, so as to protect the functions of spleen, stomach and lung, there may be target spots of Buzhong Yiqi decoction in PI3K/AKT signal pathway.


Assuntos
Adenocarcinoma/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Neoplasias Pulmonares/tratamento farmacológico , Proteína Oncogênica v-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Baço/enzimologia , Adenocarcinoma/enzimologia , Adenocarcinoma/genética , Adenocarcinoma de Pulmão , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteína Oncogênica v-akt/genética , Fosfatidilinositol 3-Quinases/genética , Transdução de Sinais/efeitos dos fármacos , Baço/efeitos dos fármacos
13.
Mar Pollut Bull ; 200: 116095, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38325205

RESUMO

An integrated observation of NOx that included coastal cities and oceanic cruises covering the Qingdao coastal waters sites (QDCW) and the Yellow Sea and East China Sea sites (YECS) was conducted in spring. The average concentrations of the coastal cities, the QDCW, and the YECS were 5.4 ± 4.1, 4.2 ± 3.5, and 2.9 ± 6.8 ppb for NO while 18.5 ± 7.2, 9.4 ± 5.2, and 4.9 ± 6.4 ppb for NO2, depicting lowest levels in the open seas. Atmospheric NO and NO2 showed similar spatial variations over the seas, the stations where the air masses originated from land or nearshore regions showed higher levels, but the decisive influencing factors were not the same in the different study areas. The calculated NOx flux value in the YECS (-8.7 × 10-17 mol N cm-2) indicated that the sea surface was a net sink of atmospheric NOx.


Assuntos
Poluentes Atmosféricos , Água do Mar , Poluentes Atmosféricos/análise , Dióxido de Nitrogênio , Monitoramento Ambiental , Oceanos e Mares , Óxidos de Nitrogênio , China
14.
J Colloid Interface Sci ; 661: 700-708, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38320406

RESUMO

The incorporation of high-valence transition metal atoms into FeNi (oxy)hydroxides may be a promising strategy to regulate the intrinsic electronic states, thereby reducing the thermodynamic barrier and accelerating oxygen evolution reaction (OER). Here, a high-valence Mo atoms doping route is proposed by an efficient self-reconstruction strategy to prepare MoFeNi (oxy)hydroxides for efficient alkaline OER. By using borides (MoNiB) as sacrificial template and Mo source, FeNi (oxy)hydroxides nanoflakes embedded with high-valence Mo atoms (MoFeNi) is successfully synthesized, which can modulate the electron coordination to improve the intrinsic catalytic activity. Remarkably, the obtained MoFeNi exhibits extremely low overpotential (η100 = 252 mV and η500 = 288 mV) and small Tafel slope (18.35 mV dec-1). The robust catalyst can run stably for hours at 500 mA cm-2. Characterization results and theoretical calculations confirmed that the addition of high-valence Mo effectively modulated the intrinsic electronic structure of metal sites and optimized the adsorption/desorption energy of the intermediates, accelerating OER reactions kinetics. By coupling MoFeNi anode with Pt/C cathode, anion exchange membrane (AEM) electrolyser can operate stably at 500 mA cm-2 with about less than 2.2 V. This research introduces a novel approach to develop ideal electrocatalysts through the incorporation of high-valence molybdenum species.

15.
J Colloid Interface Sci ; 664: 704-715, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38492371

RESUMO

The rational design and optimization of heterogeneous interface for low loading noble metal HER eletrocatalysts to facilitate the upscaling of alkaline water/seawater electrolysis is highly challenging. Herein, we present a facile deep corrosion strategy induced by NaBH4 to precisely construct an ultrasmall Ru nanoparticle-decorated Ni/NiO hybrid (r-Ru-Ni/NiO) with highly dispersed triple-phase heterostructures. Remarkably, it exhibits superior activity with only 53 mV and 70 mV at 100 mA cm-2 for hydrogen evolution reaction (HER) in alkaline water and seawater, respectively, surpassing the performance of Pt/C (109.7 mV, 100 mA cm-2, 1 M KOH). It is attributed to collaborative optimization of electroactive interfaces between well-distributed ultrasmall Ru nanoparticles and Ni/NiO hybrid. Moreover, the assembled r-Ru-Ni/NiO system just require 2.03 V at 1000 mA cm-2 in anion exchange membrane (AEM) electrolyzer, outperforming a RuO2/NF || Pt/C system, while exhibiting outstanding stability at high current densities. This study offers a logical design for accurate construction of interfacial engineering, showing promise for large-scale hydrogen production via electrochemical water splitting.

16.
Mar Environ Res ; 198: 106496, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38640691

RESUMO

The carbonate chemistry in river-dominated marginal seas is highly heterogeneous, and there is ongoing debate regarding the definition of atmospheric CO2 source or sink. On this basis, we investigated the carbonate chemistry and air-sea CO2 fluxes in a hotspot estuarine area: the Changjiang Estuary during winter and summer. The spatial characteristics of the carbonate system were influenced by water mixing of three end-members in winter, including the Changjiang freshwater with low total alkalinity (TA) concentration, the less saline Yellow Sea Surface Water with high TA, and the saline East China Sea (ECS) offshore water with moderate TA. While in summer with increased river discharge, the carbonate system was regulated by simplified two end-member mixing between the Changjiang freshwater and the ECS offshore water. By performing the end-member mixing model on DIC variations in the river plume region, significant biological addition of DIC was found in winter with an estimation of -120 ± 113 µmol kg-1 caused by wintertime organic matter remineralization from terrestrial source. While this biological addition of DIC shifted to DIC removal due to biological production in summer supported by the increased nutrient loading from Changjiang River. The pCO2 dynamics in the river plume and the ECS offshore were both subjected to physical mixing of freshwater and seawater, whether in winter and summer. In the inner estuary without horizontal mixing, the pCO2 dynamics were mainly influenced by biological uptake in winter and temperature in summer. The inner estuary, the river plume, and the ECS offshore were sources of atmospheric CO2, with their contributions varying seasonally. The Changjiang runoff enhanced the inner estuary's role as a CO2 source in summer, while intensive biological uptake reduced the river plume's contribution.


Assuntos
Dióxido de Carbono , Carbonatos , Monitoramento Ambiental , Estuários , Rios , Estações do Ano , Água do Mar , Dióxido de Carbono/análise , Carbonatos/análise , China , Rios/química , Água do Mar/química , Poluentes Químicos da Água/análise , Poluentes Atmosféricos/análise
17.
EBioMedicine ; 105: 105209, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38908099

RESUMO

BACKGROUND: Mapping gut microecological features to serum metabolites (SMs) will help identify functional links between gut microbiome and cardiometabolic health. METHODS: This study encompassed 836-1021 adults over 9.7 year in a cohort, assessing metabolic syndrome (MS), carotid atherosclerotic plaque (CAP), and other metadata triennially. We analyzed mid-term microbial metagenomics, targeted fecal and serum metabolomics, host genetics, and serum proteomics. FINDINGS: Gut microbiota and metabolites (GMM) accounted for 15.1% overall variance in 168 SMs, with individual GMM factors explaining 5.65%-10.1%, host genetics 3.23%, and sociodemographic factors 5.95%. Specifically, GMM elucidated 5.5%-49.6% variance in the top 32 GMM-explained SMs. Each 20% increase in the 32 metabolite score (derived from the 32 SMs) correlated with 73% (95% confidence interval [CI]: 53%-95%) and 19% (95% CI: 11%-27%) increases in MS and CAP incidences, respectively. Among the 32 GMM-explained SMs, sebacic acid, indoleacetic acid, and eicosapentaenoic acid were linked to MS or CAP incidence. Serum proteomics revealed certain proteins, particularly the apolipoprotein family, mediated the relationship between GMM-SMs and cardiometabolic risks. INTERPRETATION: This study reveals the significant influence of GMM on SM profiles and illustrates the intricate connections between GMM-explained SMs, serum proteins, and the incidence of MS and CAP, providing insights into the roles of gut dysbiosis in cardiometabolic health via regulating blood metabolites. FUNDING: This study was jointly supported by the National Natural Science Foundation of China, Key Research and Development Program of Guangzhou, 5010 Program for Clinical Research of Sun Yat-sen University, and the 'Pioneer' and 'Leading goose' R&D Program of Zhejiang.

18.
Nitric Oxide ; 33: 88-96, 2013 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-23810732

RESUMO

As an important signaling molecule, nitric oxide (NO) plays diverse physiological functions in plants, which has gained particular attention in recent years. We investigated the roles of NO in the growth of marine phytoplankton Platymonas subcordiforms and Skeletonema costatum under abiotic stresses. The growth of these two microalgae was obviously inhibited under non-metal stress (sodium selenium, Na2SeO3), heavy metal stress (lead nitrate, Pb(NO3)2), pesticide stress (methomyl) and UV radiation stress. After the addition of different low concentrations of exogenous NO (10(-10)-10(-8) mol L(-1)) twice each day during cultivation, the growth of these two microalgae was obviously promoted. Results showed that NO could relieve the oxidative stresses to protect the growth of the two microalgae. For different environmental stress, there is a different optimum NO concentration for marine phytoplankton. It is speculated that the protective effect of NO is related to its antioxidant ability.


Assuntos
Antioxidantes/farmacologia , Óxido Nítrico/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Fitoplâncton/efeitos dos fármacos , Análise de Variância , Proliferação de Células/efeitos dos fármacos , Peróxido de Hidrogênio/metabolismo , Metais Pesados/toxicidade , Metomil/toxicidade , Estresse Oxidativo/efeitos da radiação , Fitoplâncton/crescimento & desenvolvimento , Fitoplâncton/metabolismo , Fitoplâncton/efeitos da radiação , Superóxido Dismutase/metabolismo , Raios Ultravioleta
19.
Ying Yong Sheng Tai Xue Bao ; 34(10): 2619-2628, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-37897268

RESUMO

Determining the differences of water use characteristics of a tree species with different origins (natural forests and introduced plantations) is significantly important for forest sustainable management. Pinus sylvestris var. mongolica is an important tree species of afforestation in the 'Three North' project in China. In this study, with Pinus sylvestris var. mongolica from two origins, we monitored the sap flow velocity of sapwood (Js) of trees by thermal dissipation sap flow probes, and analyzed the relationship between water transportation and the environmental factors during the growing season. The results showed that under the typical sunny day, daily sap flow velocity (Js-daily) of trees from plantations was significantly higher than that from natural forests. The mean value of Js-daily was 132.98 and 114.86 cm·d-1 for the two origins, respectively. Trees from plantations showed higher water transportation potential than natural forests. Vapor pressure deficit (VPD) mainly showed the driving effect on the water use process of trees from natural forests. In the plantations, there was an obvious threshold effect, and the inflection point of VPD was about 1.91 kPa, with the boundary function of Js-hour increased to the maximum of 17.88 cm·h-1. Atmospheric driven transpiration potential (Js-hour/VPD) of P. sylvestris var. mongolica trees with two origins decreased with the aggravation of soil drought, but sensitivity to drought was higher in the plantations than in the natural forests, suggesting the strong ability of Pinus sylvestris var. mongolica to regulate water use process.


Assuntos
Pinus sylvestris , Pinus , Pinus sylvestris/fisiologia , Água/análise , Florestas , Árvores , Solo , China
20.
Water Res ; 247: 120770, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37897991

RESUMO

Intertidal wetland sediments are an important source of atmospheric nitrogen oxides (NOx), but their contribution to the global NOx budget remains unclear. In this work, we conducted year-round and diurnal observations in the intertidal wetland of Jiaozhou Bay to explore their regional source-sink patterns and influence factors on NOx emissions (initially in the form of nitric oxide) and used a dynamic soil reactor to further extend the mechanisms underlying the tidal pulse of nitric oxide (NO) observed in our investigations. The annual fluxes of NOx in the vegetated wetland were significantly higher than those in the wetland without vegetation. Their annual variations could be attributed to changes in temperature and the amount of organic carbon in the sediment, which was derived from vegetated plants and promoted the carbon-nitrogen cycle. Anaerobic denitrifiers had advantages in the intertidal wetland sediment and accounted for the major NO production (63.8 %) but were still limited by nitrite and nitrate concentrations in the sediment. Moreover, the tidal pulse was likely a primary driver of NOx emissions from intertidal wetlands over short periods, which was not considered in previous investigations. The annual NO exchange flux considering the tide pulse contribution (8.93 ± 1.72 × 10-2 kg N ha-1 yr-1) was significantly higher than that of the non-pulse period (4.14 ± 1.13 × 10-2 kg N ha-1 yr-1) in our modeling result for the fluxes over the last decade. Therefore, the current measurement of NOx fluxes underestimated the actual gas emission without considering the tidal pulse.


Assuntos
Óxido Nítrico , Áreas Alagadas , Ciclo do Nitrogênio , Óxidos de Nitrogênio , Nitrogênio , Carbono
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