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1.
BMC Nephrol ; 24(1): 90, 2023 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-37020293

RESUMO

BACKGROUND: Fabry disease is a rare hereditary disease involving multiple organs, and there are few reports on how the initial manifestations and renal involvement of these patients with classical and late-onset phenotype evolve with sexes and ages. To improve clinicians' understanding of Fabry disease and avoid misdiagnoses by discussing the initial manifestations, first medical specialties visited and renal involvement development in patients. METHODS: This study collected relevant data from 311 Chinese Fabry disease patients (200 males, 111 females) and descriptive statistical analysis was used to analyze the evolution of the initial manifestations and renal involvement of patients with classical and late-onset phenotype at different sexes and ages. RESULTS: Regarding the age at manifestation onset, age at the first medical specialty visited and age at the diagnosis of Fabry disease, males were earlier than females, and males with classical phenotype were earlier than males with late-onset and females with classical phenotype. In both male and female patients, the initial manifestations of classical patients were mainly acroparesthesia, and the first medical specialty visited were mainly pediatrics and neurology. The initial manifestations of late-onset patients were mainly renal and cardiovascular involvement, and the first medical specialty visited were mainly nephrology and cardiology. In classical patients, both male and female, the initial manifestations of the preschool and the juvenile groups were mainly acroparesthesia, and the frequency of renal and cardiovascular involvement in the young group was higher than that in the preschool and juvenile groups. There was no obvious renal involvement in the preschool group, renal involvement was most common in the young group and the middle-aged and elderly group. Proteinuria can appear in classical male patients as early as approximately 20 years, and renal insufficiency can occur at approximately 25 years. With age, over 50% of classical male patients can develop varying degrees of proteinuria at the age of 25 and renal insufficiency at the age of 40. 15.94% of the patients progressed to dialysis or kidney transplantation, mainly classical males. CONCLUSIONS: The initial manifestation of Fabry disease is affected by sex, age and classical/late-onset phenotype. The initial manifestations were mainly acroparesthesia and the frequency and degree of renal involvement increased gradually with aging in classical male patients.


Assuntos
Doença de Fabry , Insuficiência Renal , Criança , Pré-Escolar , Feminino , Humanos , Masculino , alfa-Galactosidase/genética , População do Leste Asiático , Doença de Fabry/diagnóstico , Proteinúria , Diálise Renal , Adolescente , Adulto Jovem , Adulto
2.
Environ Sci Technol ; 55(9): 5763-5771, 2021 05 04.
Artigo em Inglês | MEDLINE | ID: mdl-33818073

RESUMO

Coal and coal gangue spontaneous combustion (CGSC) occurs globally, causing significant environmental pollution. However, its emissions are poorly quantified and are overlooked in global or regional air pollutant emission inventories in previous studies, resulting in the underestimation of its impacts on climate, environment, and public health. This study quantified the emissions of various air pollutants originating from CGSC in Wuhai, a city in China, investigated emission characteristics, and estimated the contribution of CGSC emissions to fine particulate matter (PM2.5) air pollution and related health impacts on a regional scale. The results revealed that the CGSC-related PM2.5 emissions were approximately 4643 t a-1 (95% confidence interval (95% CI): 721; 10447), accounting for 26.3% of the total PM2.5 emissions. Alkanes, alkenes, and aromatics accounted for 69.4, 17.9, and 2.9%, respectively, of the total emissions of volatile organic compounds (VOCs). Due to CGSC emissions, the ambient PM2.5 concentration in Wuhai increased by 5.7 µg m-3 on average, while the nitrate concentration decreased. The number of premature deaths caused by exposure to ambient PM2.5 associated with CGSC reached 381 (95% CI: 290; 452) in Wuhai and surrounding cities in 2017. Urgent control strategies and engineering techniques are needed to mitigate CGSC to protect public health.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Cidades , Carvão Mineral/análise , Monitoramento Ambiental , Material Particulado/análise , Combustão Espontânea
3.
BMC Nephrol ; 20(1): 467, 2019 12 16.
Artigo em Inglês | MEDLINE | ID: mdl-31842785

RESUMO

BACKGROUND: The goal of this study was to investigate the clinical and pathological features and prognosis of idiopathic membranous nephropathy (IMN) with focal segmental lesions. METHODS: In our hospital, 305 patients with nephrotic syndrome confirmed as IMN by renal biopsy were divided into a non-focal segmental lesion group (FSGS- group) and a focal segmental glomerulosclerosis (FSGS) group (FSGS+ group) and retrospectively analyzed. In all, 180 patients were followed for periods ranging from 6 months to 2 years. The general clinicopathological data of both groups were compared, and the effects of different treatment schemes on the prognosis of both groups were observed. RESULTS: The FSGS+ group had a longer disease course, higher blood pressure levels, and higher serum creatinine and ß2-microglobulin levels than did the FSGS- group (all P < 0.05). Pathologically, the FSGS+ group had increased glomerular sclerosis, glomerular mesangial hyperplasia, and acute and chronic tubular lesion rates (all P < 0.05). The remission rate was lower in the FSGS+ group than in the FSGS- group (64.7% vs 82.2%) and, among patients in the FSGS+ group, was lower in patients treated with calmodulin inhibitors than in those treated with cyclophosphamide (P < 0.01). Survival analysis showed that the FSGS+ group had a poor prognosis (χ2 = 4.377, P = 0.036), and risk factor analysis suggested that age at renal biopsy (P = 0.006), 24-h urinary protein quantity (P = 0.01), chronic tubulointerstitial lesions (P = 0.055), and FSGS lesions (P = 0.062) were risk factors for worsening renal condition; furthermore, 24-h urinary protein quantity was an independent risk factor for worsening renal condition. CONCLUSIONS: Membranous nephropathy with FSGS is a risk factor, but not an independent risk factor, for IMN. Patients with membranous nephropathy with FSGS often present hypertension and tubule injury. The nonselective drug cyclophosphamide is preferred, and calcineurin inhibitors should be used with caution.


Assuntos
Glomerulonefrite Membranosa/sangue , Glomerulonefrite Membranosa/patologia , Glomerulosclerose Segmentar e Focal/sangue , Glomerulosclerose Segmentar e Focal/patologia , Adulto , Feminino , Seguimentos , Glomerulonefrite Membranosa/epidemiologia , Glomerulosclerose Segmentar e Focal/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade
4.
Chin J Integr Med ; 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38850479

RESUMO

OBJECTIVE: To explore the potential of metanephric mesenchymal cells (MMCs) for osteogenesis and naringin's ability to enhance this process and its molecular mechanism. METHODS: Porcine MMCs at 70 days of gestation were used as tool cells, cultured in osteogenic induction medium, identified by immunocytochemistry staining. Osteogenic potential of porcine MMCs and naringin's ability to enhance this process was tested by detecting changes in cell viability, alkaline phosphatase (ALP) activity, the expression of runt-related transcription factor 2 (Runx2), osteopontin (OPN) and osteocalcin (OCN), and the formation of mineralized nodules, and the application of the p38 signaling pathway inhibitor SB203580 vitiated the osteogenesis-promoting effect of naringin. RESULTS: Immunocytochemical staining showed that the cells were Vimentin and Six2(+), E-cadherin and CK-18(-). Naringin can activate the p38 signaling pathway to enhance the osteogenesis of porcine MMCs by increasing cell viability, ALP activity, the expressions of Runx2, OPN and OCN, and the formation of mineralized nodules (P<0.05). The application of p38 signaling pathway inhibitor SB203580 vitiated the osteogenesis-promoting effect of naringin, manifested by decreased ALP activity, the expressions of Runx2, OPN and OCN, and the formation of mineralized nodules (P<0.05). CONCLUSION: Naringin, the active ingredient of Chinese herbal medicine Rhizoma Drynariae for nourishing Shen (Kidney) and strengthening bone, enhances the osteogenic differentiation of renal MMCs through the p38 signaling pathway.

5.
J Nephrol ; 36(2): 575-591, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-35994232

RESUMO

Renal tubules play an important role in maintaining water, electrolyte, and acid-base balance. Renal tubule dysfunction can cause electrolyte disorders and acid-base imbalance. Clinically, hypokalemic renal tubular disease is the most common tubule disorder. With the development of molecular genetics and gene sequencing technology, hereditary renal tubular diseases have attracted attention, and an increasing number of pathogenic genes related to renal tubular diseases have been discovered and reported. Inherited renal tubular diseases mainly occur due to mutations in genes encoding various specific transporters or ion channels expressed on the tubular epithelial membrane, leading to dysfunctional renal tubular reabsorption, secretion, and excretion. An in-depth understanding of the molecular genetic basis of hereditary renal tubular disease will help to understand the physiological function of renal tubules, the mechanism by which the kidney maintains water, electrolyte, and acid-base balance, and the relationship between the kidney and other systems in the body. Meanwhile, understanding these diseases also improves our understanding of the pathogenesis of hypokalemia, alkalosis and other related diseases and ultimately promotes accurate diagnostics and effective disease treatment. The present review summarizes the most common hereditary renal tubular diseases (Bartter syndrome, Gitelman syndrome, EAST syndrome and Liddle syndrome) characterized by hypokalemia and alkalosis. Further detailed explanations are provided for pathogenic genes and functional proteins, clinical manifestations, intrinsic relationship between genotype and clinical phenotype, diagnostic clues, differential diagnosis, and treatment strategies for these diseases.


Assuntos
Alcalose , Síndrome de Bartter , Hipopotassemia , Nefropatias , Humanos , Hipopotassemia/etiologia , Hipopotassemia/genética , Síndrome de Bartter/diagnóstico , Síndrome de Bartter/genética , Síndrome de Bartter/terapia , Nefropatias/complicações , Alcalose/diagnóstico , Alcalose/genética , Alcalose/terapia , Água
6.
Kidney Dis (Basel) ; 9(5): 371-383, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37901710

RESUMO

Background: Renal tubular acidosis (RTA) is caused by various disruptions to the secretion of H+ by distal renal tubules and/or dysfunctional reabsorption of HCO3- by proximal renal tubules, which causes renal acidification dysfunction, ultimately leading to a clinical syndrome characterized by hyperchloremic metabolic acidosis with a normal anion gap. With the development of molecular genetics and gene sequencing technology, inherited RTA has also attracted attention, and an increasing number of RTA-related pathogenic genes have been discovered and reported. Summary: This paper focuses on the latest progress in the research of inherited RTA and systematically reviews the pathogenic genes, protein functions, clinical manifestations, internal relationship between genotypes and clinical phenotypes, diagnostic clues, differential diagnosis, and treatment strategies associated with inherited RTA. This paper aims to deepen the understanding of inherited RTA and reduce the missed diagnosis and misdiagnosis of RTA. Key Messages: This review systematically summarizes the pathogenic genes, pathophysiological mechanisms, differential diagnosis, and treatment of different types of inherited RTA, which has good clinical value for guiding the diagnosis and treatment of inherited RTA.

7.
Nat Commun ; 14(1): 5932, 2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37739948

RESUMO

The responses of the East Asian summer monsoon (EASM) to the Indian summer monsoon (ISM) have been the subject of extensive investigation. Nevertheless, it remains uncertain whether the ISM can serve as a predictor for the EASM. Here, on the basis of both observations and a large-ensemble climate model experiment, we show that the subseasonal variability of abnormal diabatic heating over India enhances precipitation over central East China, the Korean Peninsula, and southern Japan in June. ISM heating triggers Rossby wave propagation along the subtropical jet, promoting southerly winds over East Asia. The southerly winds helps steer anomalous mid-tropospheric warm advection and lower-tropospheric moisture advection toward East Asia, providing conditions preferential for rainband formation. Cluster analysis shows that, depending on jet structures, ISM heating can serve as a trigger as well as a reinforcer of the rainband.

8.
Environ Sci Pollut Res Int ; 30(13): 37055-37075, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36565426

RESUMO

Urban renewal can transform areas that are not adapted to modern urban life, allowing them to redevelop and flourish; however, the renewal process generates many new construction sites, producing environmentally harmful construction dust. The widespread use of urban green plastic cover (GPC) at construction sites and the development of high-resolution satellites have made it possible to extract the spatial distribution of construction sites and provide a basis for environmental protection authorities to protect against dust sources. Existing GPC extraction methods based on remote sensing images are either difficult to obtain the exact boundary of GPC or cannot provide corresponding algorithms according to different application scenarios. In order to determine the distribution of green plastic cover in the built-up area, this paper selects a variety of typical machine learning algorithms to classify the land cover of the test area image and selects K-nearest neighbor as the best machine learning algorithm through accuracy evaluation. Then multiple deep learning methods were used and the top networks with high overall scores were selected by comparing various aspects. Then these networks were used to predict the GPC of the test area image, and the accuracy evaluation results showed that the segmentation accuracy of deep learning was much higher than that of machine learning methods, but it took more time to predict. Therefore, combining different application scenarios, this paper gives the corresponding suggested methods for GPC extraction.


Assuntos
Algoritmos , Tecnologia de Sensoriamento Remoto , Tecnologia de Sensoriamento Remoto/métodos , Aprendizado de Máquina , Conservação dos Recursos Naturais , Reforma Urbana
9.
Sci Total Environ ; 857(Pt 2): 159500, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36265629

RESUMO

Chemical boundary conditions (BCs) are important inputs for regional chemical transport models. In this study, we use the brute-force method (BFM), process analysis (PA) and response surface model (RSM) to quantify the effects of BCs on simulated O3 concentrations in different regions of China by the weather research and forecasting with chemistry (WRF-Chem) model. We combine the model with an integrated gas-phase reaction rate (IRR) tool to further analyze the changes in the O3 chemical mechanisms. Our results show that the simulated O3 concentrations in western cities are significantly affected by the O3 in the BCs (BC-O3), which can increase the maximum simulated O3 concentration, such as in Lanzhou (36.6 µg/m3, 26.3 %), Wuhai (30.1 µg/m3, 25.5 %) and Urumqi (50.7 µg/m3, 41.2 %). In contrast, O3 generation in the eastern region is dominated by emissions. Subsequently, we compare the reaction rate changes in O3 generation and consumption under the effects of BC-O3 in the western city of Urumqi and the eastern city of Beijing. The results show that in Beijing, the O3 concentration and the related chemical reaction rates undergo little change, while in Urumqi, the concentration and reaction rates have significant differences. The BC-O3 significantly accelerates the O3 photochemical reaction process in Urumqi, resulting in increased O3 generation and consumption reaction rates; additionally, there may be a chemical reaction pathway for the formation of O3: BC-O3 + NO → NO2 + hv → O + O2 → O3. BC-O3 transmission is the main pathway of changes in the simulated O3 concentration in the study area, and the chemical reactions between BC-O3 and local pollutants are primarily characterized by O3 consumption. In conclusion, the study shows the importance of BCs for regional model simulation while providing supporting information for O3 formation in model studies.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Ozônio/análise , Monitoramento Ambiental/métodos , Tempo (Meteorologia) , China , Poluição do Ar/análise
10.
Sci Total Environ ; 858(Pt 3): 159903, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36334656

RESUMO

The aim of this study was to better understand the characteristics of volatile organic compounds (VOCs) and secondary organic aerosol (SOA) pollution in different functional areas of petrochemical industrial cities. In Lanzhou, a typical petrochemical industrial city in Northwest China, with the use of an Integrated Atmospheric Mobile Monitoring Vehicle (IAMMV), various real-time online monitoring instruments, including a VOC monitoring instrument (TH-300B) and single-particle aerosol mass spectrometer (SPAMS), were used in combination. These instruments were employed to determine PM2.5, VOCs and other factors at monitoring sites in Xigu (XG) and Chengguan (CG) districts in September 2020 and 2021, respectively. The results revealed that during the monitoring period, the average VOC concentrations at the XG and CG monitoring sites were 102.3 and 35.8 ppb, respectively. Benzene (45.58 %) and toluene (24.47 %) significantly contributed to the SOA formation potential at the XG site. M/P-xylene (27.88 %) and toluene (23.64 %) more notably contributed to the SOA formation potential at the CG site. The PM2.5 mass concentration at the XG site (24.1 µg·m-3) was similar to that at the CG site (21.2 µg·m-3), but the proportion of particulate matter components greatly differed. The proportion of organic carbon (OC) at the XG site (19.00 %) was higher than that at the CG site (9.97 %). The number of particles containing C2H3O+ (m/z = 43) accounted for 36.96 % and 15.41 % of the total particles at the XG and CG sites, respectively. The mixing ratios of OC and hybrid carbon (OCEC) with C2H3O+ (m/z = 43) were 0.81 and 0.53, respectively, at the XG site and reached only 0.48 and 0.25, respectively, at the CG site. The secondary ageing degree of particles in XG district was high. These results could provide a reference for ambient air quality improvement and the formulation of governance measures in different functional areas of petrochemical industrial cities.


Assuntos
Compostos Orgânicos Voláteis , Cidades , China , Tolueno , Carbono
11.
Environ Pollut ; 333: 122070, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37331578

RESUMO

The accuracy of determining atmospheric chemical mechanisms is a key factor in air pollution prediction, pollution-cause analysis and the development of control schemes based on air quality model simulations. However, the reaction of NH3 and OH to generate NH2 and its subsequent reactions are often ignored in the MOZART-4 chemical mechanism. To solve this problem, the gas-phase chemical mechanism of NH3 was updated in this study. Response surface methodology (RSM), integrated gas-phase reaction rate (IRR) diagnosis and process analysis (PA) were used to quantify the influence of the updated NH3 chemical mechanism on the O3 simulated concentration, the nonlinear response relationship of O3 and its precursors, the chemical reaction rate of O3 generation and the meteorological transport process. The results show that the updated NH3 chemical mechanism can reduce the error between the simulated and observed O3 concentrations and better simulate the O3 concentration. Compared with the Base scenario (original chemical mechanism simulated), the first-order term of NH3 in the Updated scenario (updated NH3 chemical mechanism simulated) in RSM passed the significance test (p < 0.05), indicating that NH3 emissions have an influence on the O3 simulation, and the effects of the updated NH3 chemical mechanism on NOx-VOC-O3 in different cities are different. In addition, the analysis of chemical reaction rate changes showed that NH3 can affect the generation of O3 by affecting the NOx concentration and NOx circulation with radicals of OH and HO2 in the Updated scenario, and the change of pollutant concentration in the atmosphere leads to the change of meteorological transmission, eventually leading to the reduction of O3 concentration in Beijing. In conclusion, this study highlights the importance of atmospheric chemistry for air quality models to model atmospheric pollutants and should attract more research focus.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Ambientais , Ozônio , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Ozônio/toxicidade , Ozônio/análise , Poluição do Ar/análise , Simulação por Computador , Poluição Ambiental/análise , Poluentes Ambientais/análise , Monitoramento Ambiental/métodos , China
12.
Huan Jing Ke Xue ; 43(2): 707-713, 2022 Feb 08.
Artigo em Zh | MEDLINE | ID: mdl-35075844

RESUMO

VOCs are the key precursors of ozone and secondary organic aerosols. The results of source apportionment for VOCs are very important for the coordinated control of ozone and second organic particulate matter. However, VOCs do not fully meet the assumption of the receptor model because the VOCs released from each source are relatively unstable in the transmission process for their reactivity. As a result, we do not accurately obtain the actual source contribution when the receptor model is used for the source apportionment of VOCs. In order to solve the problem that the relative changes in the components caused by VOCs reactivity are not consistent with the PMF model hypothesis, the aging degree of VOCs was introduced to distinguish the state characteristics after their photochemical reactions in the ambient air. According to the ratio of ethylbenzene to m/p-xylene, VOCs monitored at Wuhai were divided into three aging states:high, medium, and low. The results showed that the model parameters, such as regression equation parameters (slope and intercept), standard error, determination coefficient, and pass rate of residual error, were improved obviously compared to the sample set after classification. Because the degree of aging is closely related to the transport time of air mass and the atmospheric oxidation in the atmosphere, it also reflects the different sources of air mass to some extent. In the high-aging VOCs samples, the coking source occupied a high proportion (up to 47.20%). In the low-aging VOCs samples, the combustion source and coking source accounted for a higher proportion, 28.67% and 24.39%, respectively. After the classification according to the aging degree, the results of VOCs source apportionment by PMF are more consistent with the actual contribution of emission sources.


Assuntos
Poluentes Atmosféricos , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental , Emissões de Veículos/análise , Compostos Orgânicos Voláteis/análise
13.
Korean J Intern Med ; 37(1): 154-166, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32972118

RESUMO

BACKGROUND/AIMS: Anti-phospholipase A2 receptor (PLA2R) autoantibody is the main biomarker of idiopathic membranous nephropathy (IMN). We aimed to find a new cutoff value of anti-PLA2R for patients with IMN and to explore the relevance between this antibody and baseline clinical parameters. METHODS: A total of 670 subjects including 374 IMN cases and 296 non-IMN controls were included between January 2017 and January 2020. All clinical parameters were collected at the time of renal biopsy. The levels of anti-PLA2R were detected by a commercial enzyme-linked immunosorbent assay (ELISA) kit. The optimal cutoff value was calculated by a receiver operating characteristic curve and compared in diagnostic efficiency. RESULTS: The optimal cutoff value of anti-PLA2R for IMN was 7.45 RU/mL with the highest Youden index, and the corresponding sensitivity, specificity, positive predictive value and negative predictive value were 80.75%, 97.97%, 98.05% and 80.11%, respectively. Anti-PLA2R levels in IMN patients demonstrated a significant positive correlation with serum creatinine and 24-hour urinary protein, while they showed a negative correlation with serum albumin and estimated glomerular filtration rate. CONCLUSION: The recommended cutoff value of anti-PLA2R is 7.45 RU/mL using ELISA detection for distinguishing IMN from non-IMN nephropathy. The level of anti-PLA2R is related to baseline renal function in IMN. This new threshold can improve the diagnostic efficiency and facilitate early diagnosis of IMN.


Assuntos
Glomerulonefrite Membranosa , Autoanticorpos , Biomarcadores , Feminino , Glomerulonefrite Membranosa/diagnóstico , Glomerulonefrite Membranosa/patologia , Humanos , Masculino , Fosfolipases , Receptores da Fosfolipase A2 , Estudos Retrospectivos
14.
Sci Total Environ ; 839: 155901, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35569665

RESUMO

Measurements of ozone (O3) and its precursors were performed in the summer of 2019 in Lanzhou, a petrochemical industrial city, to better understand the reactivity of volatile organic compounds (VOCs) and their effects on O3 production. During the campaign, the daily maximum 8-hour average (MDA8) O3, NO2, and total VOC (TVOC) concentrations reached 72.2 ± 19.9 ppb, 24.9 ± 10.8 ppb, and 50.8 ± 46.1 ppb, respectively. Alkanes, alkenes, halocarbons, aromatics, and alkynes contributed 45.3%, 24.0%, 16.5%, 10.0%, and 4.2% to TVOCs, respectively. The OH reactivity and relative incremental reactivity (RIR) of VOCs at different times were calculated. The results indicated that alkenes played a predominant role, accounting for an average of 68.5% of the initial VOC reactivity. Compared to other regions, alkenes are relatively more important for O3 formation in the petrochemical industry area of Lanzhou, while aromatics are relatively less important. Generally, O3 formation occurred in a VOC-limited regime in the morning and in a transitional regime in the afternoon. The response surface methodology (RSM) combined with a chemical box model was applied to obtain relationships between O3 and its precursors and determine the most effective way to reduce the O3 concentration. Reduction in the non-alkene concentration slightly affected the O3 concentration. In contrast, the effect of nitrogen oxides (NOx) was closely related to the alkene concentration, and NOx concentration reduction could lead to an increase in the O3 concentration when alkenes were abated to less than 80% of the present concentration. To mitigate O3 pollution near the petrochemical industrial area of Lanzhou, reducing the alkene concentration, especially the C4 alkene concentration (1,3-butadiene, cis-2-butene, and trans-2-butene), was the fastest and most effective control strategy. The results of this study serve as a reference for O3 pollution control in petrochemical industrial areas.


Assuntos
Poluentes Atmosféricos , Ozônio , Compostos Orgânicos Voláteis , Poluentes Atmosféricos/análise , Alcenos , China , Monitoramento Ambiental/métodos , Ozônio/análise , Compostos Orgânicos Voláteis/análise
15.
Drug Metab Dispos ; 39(12): 2305-13, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21918037

RESUMO

The carboxylesterases (CESs) are a family of serine hydrolases that hydrolyze compounds containing an ester, amide, or thioester. In humans, two dominant forms, CES1 and CES2, are highly expressed in organs of first-pass metabolism and play an important role in xenobiotic metabolism. The current study was conducted to better understand species-related differences in substrate selectivity and tissue expression of these enzymes. To elucidate potential similarities and differences among these enzymes, a series of 4-nitrophenyl esters and a series of gemcitabine prodrugs were evaluated using enzyme kinetics as substrates of expressed and purified CESs from beagle dog, cynomolgus monkey, and human genes. For the substrates examined, human and monkey CES2 more efficiently catalyzed hydrolysis compared with CES1, whereas CES1 was the more efficient enzyme in dog. Quantitative real-time polymerase chain reaction and Western blot analyses indicate that the pattern of CES tissue expression in monkey is similar to that of human, but the CES expression in dog is unique, with no detectable expression of CES in the intestine. Loperamide, a selective human CES2 inhibitor, was also found to be a CES2-selective inhibitor in both dog and monkey. This is the first study to examine substrate specificity among dog, human, and monkey CESs.


Assuntos
Hidrolases de Éster Carboxílico/metabolismo , Animais , Sequência de Bases , Western Blotting , Hidrolases de Éster Carboxílico/genética , Cães , Humanos , Macaca fascicularis , Dados de Sequência Molecular , Reação em Cadeia da Polimerase em Tempo Real , Especificidade por Substrato
16.
Huan Jing Ke Xue ; 42(2): 616-623, 2021 Feb 08.
Artigo em Zh | MEDLINE | ID: mdl-33742855

RESUMO

There is a highly nonlinear relationship between ozone concentrations and its precursor emissions in different regions and at different times, which makes developing effective prevention and control measures difficult. An orthogonal experimental method was introduced to assess the influence of ozone precursors and their interactions on ozone formation, clarify the sensitivity of ozone generation, and propose an optimal control scheme. Based on the WRF-Chem air quality model and an emission inventory of air pollutants in Wuhai City in 2018, this study used an ozone pollution event in the Haibowan urban area (August 17 to 20 2018) to investigate the nonlinear response of ozone formation to its precursors. The orthogonal experiment shows that NOx, VOCs interactions with CO, CO, and interactions between pollutants and meteorological factors are the main factors affects ozone concentrations in the Haibowan urban area. Ozone generation was most sensitive to NOx concentrations during the hours 12:00-18:00 when standard values were exceeded. The ozone concentrations decreased significantly by 12.6 µg·m-3 (7.8%) as NOx, VOCs, and CO were reduced by 60%, 30%, and 30%, respectively. Through the analysis of chemical reaction mechanisms, it is concluded that VOCs and CO affect the photochemical reaction by reacting with·OH, HO2·and other free radicals, which causes the significant interaction between VOCs and CO in the generation of ozone. This method provides a new approach for researching the nonlinear response of ozone formation to its precursors and for proposing ozone pollution control schemes.

17.
Huan Jing Ke Xue ; 42(2): 634-642, 2021 Feb 08.
Artigo em Zh | MEDLINE | ID: mdl-33742857

RESUMO

City-scale high-resolution anthropogenic emission inventories are an important tool for ambient air quality forecasting and early warning, the analysis of underlying causes, and policy making. At present, city-scale anthropogenic emissions inventories for use in air quality models are scarce for West China. By studying the literature on emission inventories, this paper establishes a city-scale anthropogenic emission inventory for Lanzhou (HEI-LZ16) as the basis for an air quality model. The weather research and forecasting with chemistry (WRF-Chem) model was used to evaluate the applicability of the emission inventory at different resolutions in Lanzhou. The results showed that the emission amounts of SO2, NOx, CO, NH3, VOCs, PM10, PM2.5, BC, and OC in Lanzhou were 25642, 53998, 319003, 10475, 35289, 49250, 19822, 2476, and 1482 t·a-1 in 2016,respectively. Compared with the simulation scenario of multi-resolution emission inventory for China (MEIC), normalized mean error (NME) of O3 and PM2.5 under the HEI-LZ16 scenario decreased by 140.2% and 28.8%, respectively. The HEI-LZ16 inventory is more suitable for application in air pollution research in Lanzhou, which was verified by the WRF-Chem model and the observational data. The spatiotemporal distributions of PM2.5 and O3 were also analyzed using the HEI-LZ16 scenario. The ozone concentration of the maximum daily 8-h average (MDA8) in Lanzhou was low in urban areas and high in the suburbs during winter and spring, and high in the west of the urban valley and its downwind areas during summer and autumn. MDA8 in summer and autumn was influenced by easterly winds and photochemical reactions. In winter, ozone concentrations in urban areas are suppressed by NOx emissions but the concentration decreases. High PM2.5 concentrations are mainly concentrated within the Yellow River Valley. This study shows that there is a pollutant transmission channel along the western side of the Baiyin-Lanzhou Yellow River Valley, which has a greater impact on the ambient air quality in Lanzhou.

18.
Huan Jing Ke Xue ; 42(9): 4180-4190, 2021 Sep 08.
Artigo em Zh | MEDLINE | ID: mdl-34414716

RESUMO

In recent years, summer O3 pollution has become more severe in Wuhai, where the terrain is complex and industrial parks are densely distributed. However, the characteristics and formation mechanisms of this pollution have not yet been investigated and remain unclear. Analyzing the variation and formation mechanisms of O3 is crucial to the prevention and control of air pollution in this region. By analyzing characteristics and using a WRF-CMAQ model to simulate three O3 pollution periods in Wuhai from June to August 2018, this study explored the causes of O3 pollution based on in-depth process analysis, and the effects of regional transportation and local photochemical reaction on O3 were also discussed. The diurnal variation of ozone exhibited a single-peak distribution, and near-surface O3 was positively correlated with short-wave radiation and temperature, and negatively correlated with relative humidity. The areas of Shizuishan in Ningxia and the Ulanbuhe desert exhibited high O3 values during the day, while the three industrial parks in Wuhai exhibited low values during both the day and night. Process analysis showed that transportation, chemical processes, and their relative magnitudes had a significant impact on O3. Local photochemical reactions and transport during the pollution period in June and July led to an obvious increase in O3, while the impact of chemical processes was about twice as large as that of transport. The increase of O3 in August was mainly caused by transport. Further decomposition of the transportation effect showed that transportation in the south and northwest directions had a remarkable effects on the increase of O3. Together with the emission of O3 precursors, the main sources of transportation were the Yinchuan, Shizuishan, and Bayannaoer regions. Therefore, Wuhai and neighboring cities should strengthen regional joint prevention and control by jointly formulating and implementing control measures for air pollution to reduce the impact of regional transmission on O3.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Monitoramento Ambiental , Poluição Ambiental , Ozônio/análise
19.
PeerJ ; 8: e8650, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32117644

RESUMO

BACKGROUND: To discuss the clinicopathological features and prognosis of patients with idiopathic membranous nephropathy (IMN) who are serum-negative for the anti-PLA2R antibody. METHOD: Overall, 229 IMN patients were retrospectively collected in this study and classified into anti-PLA2R antibody-negative (PLA2R-, 59 cases) and antibody-positive (PLA2R+, 170 cases) groups. The clinical and pathological features of the PLA2R- group were analyzed; 162 patients in both groups were followed up, and the PLA2R antigen was detected in renal biopsies from the PLA2R- group. Kaplan-Meier and survival analyses were used to compare differences in prognosis. RESULTS: Serum albumin levels were higher and 24-hour urine protein, creatinine, and beta 2-microglobulin (BMG) levels were lower in the PLA2R- group than in the PLA2R+ group; the proportion of acute and chronic tubular lesions was also significantly lower in the PLA2R- group than in in the PLA2R+ group. After treatment, the remission rate was significantly higher in the negative group than in the positive group (93.02% vs 74.78%,), especially the rate of complete remission (51.16% vs 23.47%). Furthermore, the PLA2R antigen-positive staining rate of 43 patients in the PLA2R- group was 62.79%. Although not significant, the survival rate was higher in the PLA2R- group than in the PLA2R+ group. BMG, 24-hour urine protein and acute and chronic tubular lesions were risk factors for kidney death, and 24-hour urine protein was an independent risk factor for kidney death. CONCLUSIONS: Compared with the PLA2R+ group, the PLA2R- group had mild clinical manifestations and pathological damage and a higher clinical treatment remission rate. Renal tissue PLA2R antigen testing can be considered for patients with seronegative IMN to increase the diagnostic rate.

20.
Huan Jing Ke Xue ; 40(5): 2069-2077, 2019 May 08.
Artigo em Zh | MEDLINE | ID: mdl-31087842

RESUMO

With the rapid development of China's industry and the acceleration of urbanization, the massive use of fossil fuels has increased the concentration of air pollutants such as sulfur dioxide, particulate matter, and volatile organic compounds (VOCs) in the cities. However, there is little research on the environmental impact of volatile organic compounds from fossil fuel combustion emissions. In this paper, ozone formation potential(OFP)and secondary organic aerosol formation potential (SOAFP) of VOCs from fossil fuel combustion in Lanzhou city were calculated. The OFP and SOAFP of the cement industry were the largest, representing 45.3% and 50.9%, respectively, followed by brick and tile industries. However, when the calculations were based on tons of standard coal equivalent, the largest contributors to OFP and SOAFP of VOCs emitted from combustion were the brick and tile industries, and the smallest was the natural gas industry. VOCs from fossil fuel combustion of power plants and industry enterprises in the Xigu District are the main contributors to the OFP and SOAFP in the urban district of Lanzhou city. The contribution rates of the aromatic hydrocarbons from fossil fuel to OFP and SOAFP account for 40.0% and 67.2%, respectively. Aromatic hydrocarbons are also the main component in the top 10 species that contribute to OFP and SOAFP. The mass ratio of OFP and SOAFP per VOCs from fossil fuel combustion (2.58 t·t-1, 3.16 kg·t-1) is larger than those from biomass combustion (2.22 t·t-1, 1.38 kg·t-1).

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