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1.
Sci Total Environ ; 915: 170037, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38232856

RESUMO

Large missing sources of daytime atmospheric nitrous acid (HONO), a vital source of hydroxyl radicals (OH) through its photolysis, frequently exist in global coastal regions. In this study, ambient HONO and relevant species were measured at a coastal site in the Pearl River Delta (PRD), China, during October 2019. Relatively high concentrations (0.32 ± 0.19 ppbv) and daytime peaks at approximately 13:00 of HONO were observed, and HONO photolysis was found to be the dominant (55.5 %) source of the primary OH production. A budget analysis of HONO based on traditional sources suggested large unknown sources during the daytime (66.4 %), which had a significant correlation with the mass of coarse particles (PM2.5-10) and photolysis frequency (J(NO2)). When incorporating photolysis of the abundant nitrate measured in coarse particles with a reasonable enhancement factor relative to fine particles due to favorable aerosol conditions, the missing daytime sources of HONO could be fully compensated by coarse particles serving as the largest source at this coastal site. Our study revealed great potential of coarse particles as a strong daytime HONO source, which has been ignored before but can efficiently promote NOx recycling and thus significantly enhance atmospheric oxidation capacity.

2.
Talanta ; 270: 125524, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38128285

RESUMO

A newly constructed thermal dissociation cavity ring-down spectrometer (TD-CRDS) for the simultaneous measurement of ambient total peroxy nitrates (ΣPNs, RO2NO2), total alkyl nitrates (ΣANs, RONO2), and NO2 was presented in this work. ΣPNs and ΣANs were detected as NO2 with the CRDS instrument after thermal dissociation. PNs and ANs completely dissociated at 180 °C and 360 °C, with conversion efficiencies of 96 % and 99 %, respectively. The effects of NO2 and NO on measurement in different temperatures and two types of thermal dissociation inlet (TDI) were further explored. The influence of ambient NO2 and NO on PNs and ANs in the improved TDI (TDI-2) was significantly improved. To further enhance the measurement accuracy, the consistency of the observed NO2 in the three channels was tested, which achieved good agreement. The detection limits of the TD-CRDS instrument for NO2, ΣPNs, and ΣANs were determined as 6.5, 6.8, and 8.6 pptv (10 s, 1σ), respectively. Observations of PNs and ANs were conducted in a suburban site in Hefei, China, from September 2-30, 2021, using the TD-CRDS instrument, and the consecutive time series of PNs and ANs were derived, verifying the capability of the TD-CRDS instrument for continuous field observations of ΣPNs and ΣANs.

3.
J Med Virol ; 95(12): e29300, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-38063070

RESUMO

Little is known about antibody responses to natural Omicron infection and the risk factors for poor responders in patients with hematological malignancies (HM). We conducted a multicenter, prospective cohort study during the latest Omicron wave in Chongqing, China, aiming to compare the antibody responses, as assessed by IgG levels of anti-receptor binding domain of spike protein (anti-S-RBD), to Omicron infection in the HM cohort (HMC) with healthy control cohort (HCC), and solid cancer cohort (SCC). In addition, we intend to explore the risk factors for poor responders in the HMC. Among the 466 HM patients in this cohort, the seroconversion rate was 92.7%, no statistically difference compared with HCC (98.2%, p = 0.0513) or SCC (100%, p = 0.1363). The median anti-S-RBD IgG titer was 29.9 ng/mL, significantly lower than that of HCC (46.9 ng/mL, p < 0.0001) or SCC (46.2 ng/mL, p < 0.0001). Risk factors associated with nonseroconversion included no COVID-19 vaccination history (odds ratio [OR] = 4.58, 95% confidence interval [CI]: 1.75-12.00, p = 0.002), clinical course of COVID-19 ≤ 7 days (OR = 2.86, 95% CI: 1.31-6.25, p = 0.008) and severe B-cell reduction (0-10/µL) (OR = 3.22, 95% CI: 1.32-7.88, p = 0.010). Risk factors associated with low anti-S-RBD IgG titer were clinical course of COVID-19 ≤ 7 days (OR = 2.58, 95% CI: 1.59-4.18, p < 0.001) and severe B-cell reduction (0-10/µL) (OR = 2.87, 95% CI: 1.57-5.24, p < 0.001). This study reveals a poor antibody responses to Omicron (BA.5.2.48) infection in HM patients and identified risk factors for poor responders. Highlights that HM patients, especially those with these risk factors, may be susceptible to SARS-CoV-2 reinfection, and the postinfection vaccination strategies for these patients should be tailored. Clinical trial: ChiCTR2300071830.


Assuntos
COVID-19 , Neoplasias Hematológicas , Humanos , Formação de Anticorpos , SARS-CoV-2 , Estudos Prospectivos , Neoplasias Hematológicas/complicações , Progressão da Doença , Imunoglobulina G , Anticorpos Antivirais
4.
Sensors (Basel) ; 23(12)2023 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-37420809

RESUMO

Formaldehyde (HCHO) is a tracer of volatile organic compounds (VOCs), and its concentration has gradually decreased with the reduction in VOC emissions in recent years, which puts forward higher requirements for the detection of trace HCHO. Therefore, a quantum cascade laser (QCL) with a central excitation wavelength of 5.68 µm was applied to detect the trace HCHO under an effective absorption optical pathlength of 67 m. An improved, dual-incidence multi-pass cell, with a simple structure and easy adjustment, was designed to further improve the absorption optical pathlength of the gas. The instrument detection sensitivity of 28 pptv (1σ) was achieved within a 40 s response time. The experimental results show that the developed HCHO detection system is almost unaffected by the cross interference of common atmospheric gases and the change of ambient humidity. Additionally, the instrument was successfully deployed in a field campaign, and it delivered results that correlated well with those of a commercial instrument based on continuous wave cavity ring-down spectroscopy (R2 = 0.967), which indicates that the instrument has a good ability to monitor ambient trace HCHO in unattended continuous operation for long periods of time.


Assuntos
Formaldeído , Lasers Semicondutores , Incidência , Gases , Análise Espectral
5.
Small ; 19(40): e2300517, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37246277

RESUMO

Optical lenses require feature resolution and surface roughness that are beyond most (3D) printing methods. A new continuous projection-based vat photopolymerization process is reported that can directly shape polymer materials into optical lenses with microscale dimensional accuracy (< 14.7 µm) and nanoscale surface roughness (< 20 nm) without post-processing. The main idea is to utilize frustum layer stacking, instead of the conventional 2.5D layer stacking, to eliminate staircase aliasing. A continuous change of mask images is achieved using a zooming-focused projection system to generate the desired frustum layer stacking with controlled slant angles. The dynamic control of image size, objective and imaging distances, and light intensity involved in the zooming-focused continuous vat photopolymerization are systematically investigated. The experimental results reveal the effectiveness of the proposed process. The 3D-printed optical lenses with various designs, including parabolic lenses, fisheye lenses, and a laser beam expander, are fabricated with a surface roughness of 3.4 nm without post-processing. The dimensional accuracy and optical performance of the 3D-printed compound parabolic concentrators and fisheye lenses within a few millimeters are investiagted. These results highlight the rapid and precise nature of this novel manufacturing process, demonstrating a promising avenue for future optical component and device fabrication.

7.
Front Nutr ; 9: 1050139, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438738

RESUMO

Objective: To investigate the predictive value of nutritional status on the prognosis of patients with human immunodeficiency virus (HIV) infection-related lymphoma. Materials and methods: A total of 149 patients with HIV infection-related lymphoma who were admitted to our hospital from August 2012 to May 2022 were selected as research subjects. Based on the patient prognosis, they were divided into a poor prognosis group (n = 30) and a good prognosis group (n = 119). General data from patients in both groups were collected, and the nutritional status of the patients was evaluated using the Controlling Nutritional Status (CONUT) score. Factors affecting the prognosis of HIV infection-related lymphoma were analyzed using univariate and multivariate analyses, and a prediction model was developed based on the analyzed factors. The receiver operating characteristic (ROC) curve was used to analyze the prediction model of the CONUT score alone and included the CONUT score in the prognosis of patients with HIV infection-related lymphoma. The predictive value of the data was assessed, and a survival curve was drawn to compare the survival of patients with different nutritional statuses. Results: There were significant differences in age, B symptoms, treatment conditions, International Prognostic Index (IPI), pathological stage, Eastern Collaborative Tumor Group physical status score (ECOG PS), CD4+ cell count, ß2 microglobulin, and lactate dehydrogenase (LDH) between the poor prognosis group and the good prognosis group (p < 0.05). The CONUT score of the poor prognosis group was higher than that of the good prognosis group, and the difference was statistically significant (p < 0.05). A univariate analysis demonstrated that the age, B symptoms, treatment status, IPI, pathological stage, ECOG PS, CD4+ cell count, ß2 microglobulin, LDH, and CONUT score were prognostic factors for patients with HIV infection-related lymphoma (p < 0.05). The results of a multivariate regression analysis demonstrated that the age, B symptoms, treatment status, IPI, pathological stage, ECOG PS, and CONUT score were independent risk factors for the prognosis of patients with HIV infection-related lymphoma (p < 0.05). The prediction model was constructed according to the multivariate Cox regression analysis results. The model formula was as follows: Logit(p) = -10.687 + 1.728 × age + 1.713 × B symptoms + 1.682 × treatment status + 1.810 × IPI + 1.643 × pathological stage + 1.584 × ECOG PS + 1.779 × CONUT score. The ROC curve was used to analyze the predictive value of the CONUT score alone and the predictive model including the CONUT score on the prognosis of patients with HIV infection-related lymphoma. The predictive value of the prognosis of patients with tumors was higher (p < 0.05). According to the results of the ROC curve analysis, the patients were divided into a high CONUT group (CONUT > 6.00 points, n = 31) and a low CONUT group (CONUT ≤ 6.00 points, n = 118) based on the Optimum threshold of the CONUT score. The survival curve showed that the survival rate of the high CONUT group was lower than that of the low CONUT group (p < 0.05). Conclusion: The poor prognosis of HIV infection-related lymphoma is related to nutritional status, which is an independent risk factor affecting the prognosis of patients and can be used as a practical indicator to predict the prognosis of patients.

8.
J Oncol ; 2022: 4869732, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36213834

RESUMO

Hepatocellular carcinoma (HCC) is the seventh most common malignancy and the second most common cause of cancer-related deaths. Tumor mutational load, genomic instability, and tumor-infiltrating lymphocytes were associated with DNA damage response and repair gene changes. The goal of this study is to estimate the chances of patients with HCC surviving their disease by constructing a DNA damage repair- (DDR-) related gene profile. The International Cancer Genome Consortium (ICGC) and The Cancer Genome Atlas (TCGA) provided us with the mRNA expression matrix as well as clinical information relevant to HCC patients. Using Cox regression and LASSO analysis, DEGs strongly related to general survival were discovered in the differentially expressed gene (DEG) study. In order to assess the model's accuracy, Kaplan-Meier (KM) and receiver operating characteristic (ROC) were used. In order to compute the immune cell infiltration score and immune associated pathway activity, a single-sample gene set enrichment analysis was performed. A three-gene signature (CDC20, TTK, and CENPA) was created using stability selection and LASSO COX regression. In comparison to the low-risk group, the prognosis for the high-risk group was surprisingly poor. In the ICGC datasets, the predictive characteristic was confirmed. A receiver operating characteristic (ROC) curve was calculated for each cohort. The risk mark for HCC patients is a reliable predictor according to multivariate Cox regression analysis. According to ssGSEA, this signature was highly correlated with the immunological state of HCC patients. There was a significant correlation between the expression levels of prognostic genes and cancer cells' susceptibility to antitumor therapies. Overall, a distinct gene profile associated with DDR was identified, and this pattern may be able to predict HCC patients' long-term survival, immune milieu, and chemotherapeutic response.

9.
J Cell Mol Med ; 26(19): 5067-5077, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36056692

RESUMO

Little is known about the incidence, clinical characteristics and prognostic factors in HIV associated lymphoma as these are less common than HIV-negative lymphoma in China. Currently, there are no standard guidelines for treatment of these patients. Therefore, we performed a study to analyse the clinical characteristics and outcomes of newly diagnosed HIV-associated aggressive B-cell non-Hodgkin's lymphoma (NHL) patients in Chongqing University Cancer Hospital (CUCH). Totally 86 newly diagnosed HIV-associated aggressive B-cell NHL patients in CUCH, southwest China, from July 2008 to August 2021, were analysed. In the entire cohort, median age was 48 years (range, 23-87 years), and more patients were male (87.2%). Most patients had elevated lactate dehydrogenase (LDH) (82.6%), advanced ann arbor stage (80.2%) and high IPI score (IPI score, 3-5) (62.7%) at diagnosis. Median CD4+ T-cell count at diagnosis was 191/µl (range, 4-1022), 84 patients (97.7%) were on combination antiretroviral therapy (cART) at lymphoma diagnosis. In DLBCL patients, cox multivariate analysis showed that age ≥ 60 (HR = 2.251, 95%CI 1.122-4.516; p = 0.012), elevated LDH (HR = 4.452, 95%CI 1.027-19.297; p = 0.041) and received less than two cycles of chemotherapy (HR = 0.629, 95%CI 0.589-1.071; p = 0.012) were independent risk factors for adverse prognosis based on PFS. Age ≥ 60 (HR = 3.162, 95%CI 1.500-6.665; p = 0.002) and received less than two cycles of chemotherapy (HR = 0.524, 95%CI 0.347-0.791; p = 0.002) were also independent risk factor for adverse prognosis based on OS. In BL patients, cox multivariate analysis showed that elevated LDH and received less than two cycles of chemotherapy were independent risk factors for adverse prognosis. In the DLBCL group, median PFS times in the received rituximab and no received rituximab groups were not reached and 12 months, respectively (p = 0.006). Median OS times were not reached and 36 months, respectively (p = 0.021). In the BL group, median PFS times in the received rituximab and no received rituximab groups were not reached and 4.8 months, respectively (p = 0.046). Median OS times were not reached and 10.1 months, respectively (p = 0.035). Overall, these data indicated that standardized anti-lymphoma therapy and rituximab administration were significantly associated with improved outcomes in patients with HIV-associated DLBCL and BL.


Assuntos
Infecções por HIV , Adulto , Idoso , Idoso de 80 Anos ou mais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ciclofosfamida , Doxorrubicina , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Lactato Desidrogenases , Linfoma de Células B/diagnóstico , Linfoma de Células B/tratamento farmacológico , Linfoma de Células B/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Rituximab/uso terapêutico , Adulto Jovem
10.
Genes Dis ; 9(4): 1099-1113, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35685466

RESUMO

The regulation of ß-cell mass in the status of nondiabetic obesity remains not well understood. We aimed to investigate the role of circulating exosome-like vesicles (ELVs) isolated from humans with simple obesity in the regulation of islet ß-cell mass. Between June 2017 and July 2019, 81 subjects with simple obesity and 102 healthy volunteers with normal weight were recruited. ELVs were isolated by ultra-centrifugation. The proliferations of ß-cells and islets were measured by 5-ethynl-2'-deoxyuridine (EdU). Protein components in ELVs were identified by Quantitative Proteomic Analysis and verified by Western blot and ELISA. The role of specific exosomal protein was analyzed by gain-of-function approach in ELVs released by 3T3-L1 preadipocytes. Circulating ELVs from subjects with simple obesity inhibited ß-cell proliferation in vitro without affecting its apoptosis, secretion, and inflammation. The protein levels of Rictor and Omentin-1 were downregulated in circulating ELVs from subjects with simple obesity and associated with the obesity-linked pathologic conditions. The ELV-carried Omentin-1 and Omentin-1 protein per se were validated to increase ß-cell proliferation and activate Akt signaling pathway. Moreover, Omentin-1 in ELVs was downregulated by insulin. The circulating ELVs may act as a negative regulator for ß-cell mass in nondiabetic obesity through inhibiting ß-cell proliferation. This effect was associated with downregulated Omentin-1 protein in ELVs. This newly identified ELV-carried protein could be a mediator linking insulin resistance to impaired ß-cell proliferation and a new potential target for increasing ß-cell mass in obesity and T2DM.

11.
Sci Total Environ ; 838(Pt 1): 155924, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35577098

RESUMO

Atmospheric oxidation is a driving force of complex air pollution, and accurate hydroxyl radical (OH) measurement is helpful in investigating the radical-cored photooxidation mechanism in the troposphere. A self-developed laser-induced fluorescence instrument by the Anhui Institute of Optics Fine Mechanics, Chinese Academy of Sciences (AIOFM-LIF), was able to measure OH concentration with high sensitivity and good time resolution, and a detection limit of 1.7 × 105 cm-3 (1σ, 30 s). A long-period, multi-level intercomparison of hydroxyl radical (OH) measurements between AIOFM-LIF and PKU-LIF (the Peking University laser-induced fluorescence system) was conducted in Chengdu, China. The measurement between two instruments was in excellent agreement in the 5-min time resolution. Linear regression analysis reported a linear slope of 0.96 with a 0.68 × 106 cm-3 offset, and the correlation coefficient R2 was 0.85. The overall linearity with only a slight offset indicated a negligible influence on OH measurement. No noticeable artifacts from ozonolysis were observed under the condition of high ozone and ozonolysis-related compound concentrations. In addition to the subtraction of background signal through wavelength modulation, the dynamic correction on ozone photolysis interference ensured high intercomparison quality in both relatively constant and rapidly varying periods. Based on the reliability of OHAIOFM and OHPKU, comparisons under different oxidation-related species (NOx, VOCs, O3, PM2.5) levels and typical scenarios (rich-BVOC and high-reactivity) were carried out to evaluate the performance under complex atmospheres. A slightly higher drift was observed in a certain scenario, but the general data variability due to environmental changes did not affect the measurement accuracy. The intercomparison demonstrated that both systems are able to achieve reliable OH data under typical conditions of complex atmospheric pollution in China. Additional improvements are necessary for future intercomparisons in order to enhance the confidence in OH detection accuracy.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Ozônio , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Atmosfera/análise , Humanos , Radical Hidroxila , Ozônio/análise , Reprodutibilidade dos Testes
12.
J Environ Sci (China) ; 114: 376-390, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35459501

RESUMO

Comprehensive observations of the nocturnal atmospheric oxidation of NO3 and N2O5 were conducted at a suburban site in Changzhou in the YRD using cavity ring-down spectroscopy (CRDS) from 27 May to 24 June, 2019. High concentrations of NO3 precursors were observed, and the nocturnal production rate of NO3 was determined to be 1.7 ± 1.2 ppbv/hr. However, the nighttime NO3 and N2O5 concentrations were relatively low, with maximum values of 17.7 and 304.7 pptv, respectively, illustrating the rapid loss of NO3 and N2O5. It was found that NO3 dominated the nighttime atmospheric oxidation, accounting for 50.7%, while O3 and OH only contributed 34.1% and 15.2%, respectively. For the reactions of NO3 with volatile organic compounds (VOCs), styrene was found to account for 60.3%, highlighting its dominant role in the NO3 reactivity. In general, the contributions of the reactions between NO3 and VOCs and the N2O5 uptake to NO3 loss were found to be about 39.5% and 60.5%, respectively, indicating that N2O5 uptake also played an important role in the loss of NO3 and N2O5, especially under the high humidity conditions in China. The formation of nitrate at night mainly originated from N2O5 uptake, and the maximum production rate of NO3- reached 6.5 ppbv/hr. The average NOx consumption rate via NO3 and N2O5 chemistry was found to be 0.4 ppbv/h, accounting for 47.9% of the total NOx removal. The predominant roles of NO3 and N2O5 in nitrate formation and NOx removal in the YRD region was highlighted in this study.


Assuntos
Nitratos , Rios , China , Monitoramento Ambiental , Nitratos/análise , Óxidos de Nitrogênio/química
13.
Angew Chem Int Ed Engl ; 61(21): e202201638, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35275427

RESUMO

OH radicals in the air maintain the oxidizing power of the troposphere. A conventional view is that particulate matter (PM) in the atmosphere is a major sink of OH radicals, thereby lowering the oxidizing power of atmosphere in the event of high-level PM. By contrary, our joint experimental/theoretical study reveals a new mechanism for the generation of gaseous OH radicals by carbonaceous soot particles. We show that water and O2 react on carbonaceous surfaces and give rise to gaseous OH radicals under irradiation. With ample delocalized π electrons, carbonaceous surfaces enable the easy desorption of hydroxyl groups to produce gaseous OH radicals, evidenced by direct observation of the steady generation of OH radicals on a carbonaceous surface. Our results reveal a new chemical mechanism for the production of OH radicals.

14.
Natl Sci Rev ; 9(2): nwab103, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35145701

RESUMO

Smog chamber experimental systems, which have been widely used in laboratory simulation for studying atmospheric processes, are comprehensively reviewed in this paper. The components, development history, main research topics and main achievements of smog chambers are introduced. Typical smog chambers in the world, including their volumes, wall materials, light sources and features, are summarized and compared. Key factors of smog chambers and their influences on the simulation of the atmospheric environment are discussed, including wall loss, wall emission and background pollutants. The features of next-generation smog chambers and their application prospect in future studies of the atmospheric environment are also outlined in this paper.

15.
Sci Total Environ ; 823: 153425, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35090930

RESUMO

The research on the mechanism of combined air pollution in the Yangtze-Huaihe region, which is characterized by unique meteorological and geographical conditions and pollution emission characteristics, is still insufficient. We performed an experiment on key pollutants and an ozone formation study in Hefei, which is a pivotal city in the Yangtze-Huaihe region, from September 1 to 20, 2020. The aerosols retrieved via two-dimensional Multi-axis Differential Optical Absorption Spectroscopy (2D-MAX-DOAS) with a Boltzmann-shaped a priori profile had the best agreement with the results of Light Detection and Ranging (LIDAR) and sun-photometer measurements among the three typical a priori profiles (Gaussian, Boltzmann, and exponential shapes). The correlation coefficients of the near-surface gas concentrations retrieved using both 2D-MAX-DOAS and in situ measurements were 0.86 (NO2) and 0.61 (HCHO). The high NO2 and HCHO concentrations were observed at azimuths of 180° and 315° at heights of 0.8-1.5 km, and they may have been emitted by aircrafts. Importantly, the ratio of HCHO to NO2 during a typical pollution episode revealed that the factors controlling the O3 formation changed with altitude: VOCs (surface) to NOx (0.4 km) to transition (1.0 km) to VOCs (1.6 km). Moreover, the effect of VOCs on the O3 generation was stronger than that of NOx, especially in the downtown area of Hefei. When the ratio of HCHO to NO2 was 3.55-7.46, the ozone concentration in Hefei could be controlled well, especially at the optimal value of 5.50.


Assuntos
Poluentes Atmosféricos , Ozônio , Poluentes Atmosféricos/análise , China , Monitoramento Ambiental/métodos , Dióxido de Nitrogênio/análise , Ozônio/análise
16.
Sci Total Environ ; 810: 152275, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-34902401

RESUMO

A continuous wintertime observation of ambient OH and HO2 radicals was first carried out in Shanghai, in 2019. This effort coincided with the second China International Import Expo (CIIE), during which strict emission controls were implemented in Shanghai, resulting in an average PM2.5 concentration of less than 35 µg/m3. The self-developed instrument based on the laser-induced fluorescence (LIF) technique reported that the average OH radical concentration at noontime (11:00-13:00) was 2.7 × 106 cm-3, while the HO2 concentration was 0.8 × 108 cm-3. A chemical box model utilizing the Regional Atmospheric Chemical Mechanism 2 (RACM2), which is used to simulate pollutant reactions and other processes in the troposphere and which incorporates the Leuven isoprene mechanism (LIM1), reproduced the OH concentrations on most days. The HO2 concentration was underestimated, and the observed-to-modelled ratio demonstrated poor performance by the model, especially during the elevated photochemistry period. Missing primary peroxy radical sources or unknown behaviors of RO2 for high-NOx regimes are possible reasons for the discrepancy. The daytime ROx production was controlled by various sources. HONO photolysis accounted for more than one half (0.83 ppb/h), and the contribution from formaldehyde, OVOCs and ozone photolysis was relatively similar. Active oxidation paths accelerated the rapid ozone increase in winter. The average ozone production rate was 15.1 ppb/h, which is comparable to that of a Beijing suburb (10 ppb/h for the 'BEST-ONE') but much lower than that of Beijing's center (39 ppb/h in 'PKU' and 71 ppb/h in 'APHH') in wintertime. Cumulative local ozone based on observed peroxy radicals was five times higher than the value simulated by the current model due to the underprediction of HO2 and RO2 under the high-NOx regime. This analysis provides crucial information for subsequent pollution control policies in Shanghai.


Assuntos
Ozônio , China , Formaldeído , Oxirredução , Ozônio/análise , Fotólise
17.
Diabetes Metab Syndr Obes ; 14: 2717-2725, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34163199

RESUMO

OBJECTIVE: To explore the efficacy of the hospital glycemic management system with information integration in patients with malignant tumors and hyperglycemia. METHODS: Three hundred ninety-three patients diagnosed with malignant tumors with hyperglycemia and hospitalized in the non-endocrinology department of a specialized cancer hospital from March 2019 to November 2020 were recruited. All the patients were diagnosed and treated according to the clinical department and disease course. In total, 196 patients were divided into the control group, who received the conventional blood glucose management mode, and 197 patients were divided into the intervention group, who received the hospital glycemic management system with information integration. The average daily glucose levels were recorded before and after breakfast, lunch, and dinner, at bedtime and at night. The average glucose level, glucose compliance rate, hypoglycemia rate, hyperglycemia rate, glucose measurements per day, average number of hospitalization days and patient satisfaction were compared between the groups. RESULTS: In the intervention group, the average glucose level was significantly lower than that in the control group (P<0.05). The hyperglycemia and hypoglycemia rates in the intervention group were lower than those in the control group (P<0.05). The glucose compliance rate in the intervention group was higher than that in the control group (P<0.05). The highest blood glucose level in the intervention group was lower than that in the control group (P<0.05), and the lowest blood glucose level was higher than that in the control group (P<0.05). The glucose measurements per day in the intervention group were higher than those in the control group, and the average number of hospitalization days in the intervention group was lower than that in the control group (P<0.05). Patient satisfaction in the intervention group was higher than that in the control group (P<0.05). CONCLUSION: The hospital glycemic management system with information integration significantly improved the glycemic management of patients with malignant non-endocrine tumors and hyperglycemia, including their glucose level and glucose compliance rate, as well as patient satisfaction, and reduced the average number of hospitalization days and risk of hyperglycemia/hypoglycemia.

18.
Sci Total Environ ; 772: 144829, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33578154

RESUMO

This study reports on the first continuous measurements of ambient OH and HO2 radicals at a suburban site in Chengdu, Southwest China, which were collected during 2019 as part of a comprehensive field campaign 'CompreHensive field experiment to explOre the photochemical Ozone formation mechaniSm in summEr - 2019 (CHOOSE-2019)'. The mean concentrations (11:00-15:00) of the observed OH and HO2 radicals were 9.5 × 106 and 9.0 × 108 cm-3, respectively. To investigate the state-of-the-art chemical mechanism of radical, closure experiments were conducted with a box model, in which the RACM2 mechanism updated with the latest isoprene chemistry (RACM2-LIM1) was used. In the base run, OH radicals were underestimated by the model for the low-NO regime, which was likely due to the missing OH recycling. However, good agreement between the observed and modeled OH concentrations was achieved when an additional species X (equivalent to 0.25 ppb of NO mixing ratio) from one new OH regeneration cycle (RO2 + X â†’ HO2, HO2 + X â†’ OH) was added into the model. Additionally, in the base run, the model could reproduce the observed HO2 concentrations. Discrepancies in the observed and modeled HO2 concentrations were found in the sensitivity runs with HO2 heterogeneous uptake, indicating that the impact of the uptake may be less significant in Chengdu because of the relatively low aerosol concentrations. The ROx (= OH + HO2 + RO2) primary source was dominated by photolysis reactions, in which HONO, O3, and HCHO photolysis accounted for 34%, 19%, and 23% during the daytime, respectively. The efficiency of radical cycling was quantified by the radical chain length, which was determined by the NO to NO2 ratio successfully. The parameterization of the radical chain length may be very useful for the further determinations of radical recycling.

19.
J Environ Sci (China) ; 99: 40-50, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33183715

RESUMO

An instrument to detect atmospheric HO2 radicals using fluorescence assay by gas expansion (FAGE) technique has been developed. HO2 is measured by reaction with NO to form OH and subsequent detection of OH by laser-induced fluorescence at low pressure. The system performance has been improved by optimizing the expansion distance and pressure, the influence factors of HO2 conversion efficiency are also studied. The interferences of RO2 radicals were investigated by determining the conversion efficiency of RO2 to OH during the measurement of HO2. The dependence of the conversion of HO2 on NO concentration was investigated, and low HO2 conversion efficiency was selected to realize the ambient HO2 measurement, where the conversion efficiency of RO2 derived by propane, ethene, isoprene and methanol to OH has been reduced to less than 6% in the atmosphere. Furthermore, no significant interferences from PM2.5 and NO were found in the ambient HO2 measurement. The detection limits for HO2 (S/N = 2) are estimated to 4.8 × 105 cm-3 and 1.1 × 106 cm-3 ( [Formula: see text] = 20%) under night and noon conditions, with 60 sec signal integration time. The instrument was successfully deployed during STORM-2018 field campaign at Shenzhen graduate school of Peking University. The concentration of atmospheric HOx radical and the good correlation of OH with j(O1D) was obtained here. The diurnal variation of HOx concentration shows that the OH maximum concentration of those days is about 5.3 × 106 cm-3 appearing around 12:00, while the HO2 maximum concentration is about 4.2 × 108 cm-3 appearing around 13:30.


Assuntos
Atmosfera , Fluorescência
20.
Artigo em Inglês | MEDLINE | ID: mdl-32727744

RESUMO

INTRODUCTION: Aldosterone is a mediator of progressive renal disease, but the mechanisms for aldosterone-mediated renal impairment in mice with diabetes are not fully defined. METHODS: Aldosterone and/or mineralocorticoid receptor antagonist eplerenone were used to treat the db/db mice with diabetes. Proximal tubule epithelial cells (PTECs) and fibroblasts were cultured. Blood and kidney samples from patients with diabetes with or without diabetic kidney disease (DKD) were used to verify the findings from animals and cultured cells. RESULTS: We found that aldosterone promoted proteinuria and tubulointerstitial extracellular matrix (ECM) accumulation in db/db mice with diabetes while eplerenone mitigated the adverse effect of aldosterone. However, coculture of PTECs and fibroblasts found that when PTECs-derived extracellular vesicles (EVs) were taken up by fibroblasts, ECM production increased remarkably. Moreover, C57BL/6 mice injected with EVs from renal cortex of aldosterone-treated db/db mice showed increased ECM accumulation. Function of the ingredients of PTECs-derived EVs were analyzed, and RNAs were identified to be responsible for the EVs-induced fibroblast dysfunction. Furthermore, microRNA (miRNA) array analysis revealed that miR-196b-5p was the most remarkably increased miRNA in PTECs-derived EVs with aldosterone stimulation. Overexpression of miR-196b-5p in fibroblasts increased ECM production, accompanied by inhibition of the SOCS2 expression and enhanced STAT3 phosphorylation. In addition, plasma levels of miR-196b-5p was higher in patients with DKD as compared with patients without DKD and miR-196b-5p levels positively correlated with the albuminuria concentration. In kidney specimens from patients with diabetes, expression of miR-196b-5p, located mainly in PTECs, increased in patients with DKD as compared with the non-DKD. CONCLUSION: This study demonstrates the involvement of miR-196b-5p-EVs pathway as a novel mechanism in aldosterone-induced renal fibrosis in diabetes. EVs rich in miR-196b-5p mediate the crosstalk between PTECs and fibroblast during the development of renal fibrosis, which might be associated with STAT3/SOCO2 signaling pathway.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Vesículas Extracelulares , MicroRNAs , Aldosterona , Animais , Nefropatias Diabéticas/induzido quimicamente , Nefropatias Diabéticas/genética , Células Epiteliais , Fibrose , Humanos , Camundongos , Camundongos Endogâmicos C57BL , MicroRNAs/genética
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