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1.
Environ Sci Technol ; 2024 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-38956968

RESUMO

Elevated levels of atmospheric molecular chlorine (Cl2) have been observed during the daytime in recent field studies in China but could not be explained by the current chlorine chemistry mechanisms in models. Here, we propose a Cl2 formation mechanism initiated by aerosol iron photochemistry to explain daytime Cl2 formation. We implement this mechanism into the GEOS-Chem chemical transport model and investigate its impacts on the atmospheric composition in wintertime North China where high levels of Cl2 as well as aerosol chloride and iron were observed. The new mechanism accounts for more than 90% of surface air Cl2 production in North China and consequently increases the surface air Cl2 abundances by an order of magnitude, improving the model's agreement with observed Cl2. The presence of high Cl2 significantly alters the oxidative capacity of the atmosphere, with a factor of 20-40 increase in the chlorine radical concentration and a 20-40% increase in the hydroxyl radical concentration in regions with high aerosol chloride and iron loadings. This results in an increase in surface air ozone by about 10%. This new Cl2 formation mechanism will improve the model simulation capability for reactive chlorine abundances in the regions with high emissions of chlorine and iron.

2.
Sci Total Environ ; 941: 173782, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-38848916

RESUMO

The pollution burdens and compositions of atmospheric brown carbon (BrC) that determine their impacts on climate-health-ecosystems have not been well studied, particularly in some mega-economic coastal areas. Herein, atmospheric BrC samples synchronously collected from urban Shanghai (SH) and Huaniao Island (HNI) in the East China Sea during winter were characterized through ultrahigh-performance liquid chromatography-diode array detector-high resolution mass spectrometry (UHPLC-DAD-HRMS). The three polarity-dependent BrC fractions exhibited significant differences in both light absorption and chromophore composition. The average light absorption coefficients of BrC subfractions at 365 nm in SH were 2.6-3.7 times higher than those in HNI. The water-insoluble BrC (WIS-BrC) and humic-likes BrC (HULIS-BrC) dominated the total BrC absorption in SH (45 ± 7 %) and HNI (43 ± 6 %), respectively. Compared with SH, the higher O/Cw, lower molecule conjugation degree, and reduced mass absorption efficiency at 365 nm (MAE365) in HNI imply a potential bleaching mechanism during the transportation oxidation process. Thousands of BrC chromophores were detected at both sites. >20 major chromophores with strong absorption were unambiguously identified in HULIS-BrC and accounted for ∼40 % of the HULIS light absorption at 365 nm at both sites. These chromophores in SH HULIS-BrC featured oxygenated aromatics and nitroaromatics, while alkyl benzenesulfonic acids with emissions from cargo ships were found in HNI HULIS-BrC. Moreover, 22 major chromophores identified in WIS-BrC included alkaloids, polyaromatic hydrocarbons (PAHs), and carbonyl oxygenated PAHs, contributing 39 % and 49 % of the WIS-BrC light absorption at 365 nm in SH and HNI, respectively. Ascertaining the molecular-specific optical properties of BrC chromophores over the mega-economic coastal area is helpful for the predictive understanding of the sources and evolution of BrC, as well as its atmospheric behavior from land to sea.

3.
J Hazard Mater ; 474: 134697, 2024 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-38823102

RESUMO

Airborne pathogens severely threaten public health worldwide. Air disinfection is essential to ensure public health. However, excessive use of disinfectants may endanger environmental and ecological security due to the residual disinfectants and their by-products. This study systematically evaluated disinfection efficiency, induction of multidrug resistance, and the underlying mechanisms of disinfectants (NaClO and H2O2) on airborne bacteria. The results showed that airborne bacteria were effectively inactivated by atomized NaClO (>160 µg/L) and H2O2 (>320 µg/L) after 15 min. However, some bacteria still survived after disinfection by atomized NaClO (0-80 µg/L) and H2O2 (0-160 µg/L), and they exhibited significant increases in antibiotic resistance. The whole-genome sequencing of the resistant bacteria revealed distinct mutations that were responsible for both antibiotic resistance and virulence. This study also provided evidences and insights into possible mechanisms underlying the induction of antibiotic resistance by air disinfection, which involved intracellular reactive oxygen species formation, oxidative stress responses, alterations in bacterial membranes, activation of efflux pumps, and the thickening of biofilms. The present results also shed light on the role of air disinfection in inducing antibiotic resistance, which could be a crucial factor contributing to the global spread of antibiotic resistance through the air.


Assuntos
Bactérias , Desinfetantes , Desinfecção , Peróxido de Hidrogênio , Peróxido de Hidrogênio/farmacologia , Desinfetantes/farmacologia , Desinfecção/métodos , Bactérias/efeitos dos fármacos , Bactérias/genética , Microbiologia do Ar , Biofilmes/efeitos dos fármacos , Hipoclorito de Sódio/farmacologia , Farmacorresistência Bacteriana/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Antibacterianos/farmacologia , Cloro/farmacologia , Espécies Reativas de Oxigênio/metabolismo
4.
Sci Total Environ ; 931: 172918, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38697522

RESUMO

The source apportionment and main formation pathway of nitrate aerosols in China are not yet fully understood. In this study, PM2.5 samples were collected in Shanghai in the summer and winter of 2019. Water-soluble inorganic ions and isotopic signatures of stable nitrogen (δ15N-NO3-) and stable oxygen (δ18O-NO3-) in PM2.5 were determined. The results showed that NO3- was less important in summer (NO3-/SO42- = 0.4 ± 0.8), while it became the dominant species in winter (52.1 %). The average values of δ15N-NO3- and δ18O-NO3- in summer were + 2.0 ± 6.1 ‰ and 63.3 ± 9.4 ‰ respectively, which were significantly lower than those in winter (+7.2 ± 3.4 ‰ and 88.3 ± 12.1 ‰), indicating discrepancies between NOx sources and nitrate formation pathways. Both δ15N-NO3- and δ18O-NO3- were elevated at night, demonstrating that N2O5 hydrolysis contributed to the nocturnal nitrate increase even in summer. The contribution of the OH oxidation pathway to nitrate aerosols averaged at 70.5 ± 17.0 % in summer and N2O5 hydrolysis dominated the nitrate production in winter (approximately 80 %). On average, vehicle exhaust, coal combustion, natural gas burning, and soil emission contributed 50.7 %, 21.5 %, 15.9 %, and 11.9 %, respectively, to nitrate aerosols in summer, and contributed 56.8 %, 23.9 %, 13.6 %, and 5.7 %, respectively, to nitrate production in winter. Notably, natural gas burning is a non-negligible source of nitrate aerosols in Shanghai. In contrast to an inverse correlation between δ15N-NO3- and PM2.5, the value of δ18O-NO3- was positively correlated with nitrate concentration and aerosol liquid water content (ALWC) in winter, suggesting that explosive growth of nitrate was driven by continuous accumulation of N-depleted NOx and rapid N2O5 hydrolysis under calm and humid conditions. To continuously improve air quality, priority control should be given to vehicle emissions as the dominant source of NOx and volatile organic compounds (VOCs) in Shanghai.

5.
Sci Total Environ ; 939: 173636, 2024 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-38821278

RESUMO

Low-molecular-weight (LMW) organic acids are among the most abundant water-soluble organic compounds, but their gas-particle partitioning mechanism remains unclear. In the present study, LMW organic acids were measured using a URG 9000D Ambient Ion Monitor in suburban Shanghai. The average concentrations of formic acid, acetic acid, oxalic acid, and methanesulfonic acid (MSA) in PM2.5 were 405 ± 116, 413 ± 11, 475 ± 266, and 161 ± 54 ng m-3, respectively. The particle fraction exceeded 30 % for formic acid and acetic acid. Model predictions underestimated the particle-phase monocarboxylic acids (MCAs) from the factor of 102 at the highest RH to 107 at the lowest RH. The average measured intrinsic Henry's law constants (Hmea) for formic acid, acetic acid, oxalic acid, and MSA were 3.8 × 107, 4.5 × 107, 8.7 × 108, and 3.4 × 107 mol L-1 atm-1, respectively, approximately four orders of magnitude higher than their literature-based intrinsic Henry's law constants (Hlit) for MCAs and approximately four orders of magnitude lower than Hlit, MSA. The ratio of Hmea /Hlit for MCAs ranged over three orders of magnitude, depending on relative humidity. The strong deviations at low RHs are attributed to the dominance of absorption by the organic phase. The discrepancy at the highest RH possibly relates to surfactant effects and dimer formation. We used Hmea as a model input for the first time to estimate the phase partitioning of particulate MCAs, finding that >80 % of MCAs resided in the organic phase under dry conditions. We propose parameterizing Hmea as model input to predict the multiphase partitioning of MCAs.

6.
Eur J Oncol Nurs ; 70: 102549, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38692158

RESUMO

OBJECTIVE: To evaluate the effectiveness of Orem's self-care model in preparing hospitals for the discharge of patients with colorectal cancer who undergo enterostomy. METHODS: 92 patients with enterostomy were recruited between February 2022 and February 2023 from a general tertiary hospital. The participants were assigned to either the intervention group or the control group randomly. The intervention group received Orem's self-care program and a three-month follow-up, whereas the control group received only routine care and a three-month follow-up. Discharge readiness, self-care ability, and stoma-quality-of-life data were collected at hospital discharge (T1), 30 days (T2), and 90 days (T3) after discharge. RESULTS: The intervention group had substantially higher discharge readiness (knowledge, p < 0.001; coping ability, p = 0.006; personal status, p = 0.001; expected support, p = 0.021; total score, p < 0.001), better self-care ability at T1 (self-care knowledge, p < 0.001; self-care skills, p = 0.010), better total quality of life (QoL) at T1, T2, and T3 (p < 0.001; p = 0.006; p = 0.014); better stoma management and daily routine at T1 (p = 0.004; p < 0.001); and better daily routine at T2 (p = 0.009) than the control group. CONCLUSIONS: The designed discharge readiness program based on Orem's self-care could promote effective patient discharge readiness, self-care knowledge, self-care skills, and QoL. TRIAL REGISTRATION: The trial number ChiCTR2200056302 registered on ClinicalTrials.gov.


Assuntos
Neoplasias Colorretais , Enterostomia , Alta do Paciente , Qualidade de Vida , Autocuidado , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Idoso , Neoplasias Colorretais/cirurgia , Adulto , Adaptação Psicológica
7.
Environ Sci Technol ; 58(23): 10185-10194, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38804824

RESUMO

The relaxation of restrictions on Chinese Spring Festival (SF) firework displays in certain regions has raised concerns due to intensive emissions exacerbating air quality deterioration. To evaluate the impacts of fireworks on air quality, a comparative investigation was conducted in a city between 2022 (restricted fireworks) and 2023 SF (unrestricted), utilizing high time-resolution field observations of particle chemical components and air quality model simulations. We observed two severe PM2.5 pollution episodes primarily triggered by firework emissions and exacerbated by static meteorology (contributing approximately 30%) during 2023 SF, contrasting with its absence in 2022. During firework displays, freshly emitted particles containing more primary inorganics (such as chloride and metals like Al, Mg, and Ba), elemental carbon, and organic compounds (including polycyclic aromatic hydrocarbons) were predominant; subsequently, aged particles with more secondary components became prevalent and continued to worsen air quality. The primary emissions from fireworks constituted 54% of the observed high PM2.5 during the displays, contributing a peak hourly PM2.5 concentration of 188 µg/m3 and representing over 70% of the ambient PM2.5. This study underscores that caution should be exercised when igniting substantial fireworks under stable meteorological conditions, considering both the primary and potential secondary effects.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/análise , Monitoramento Ambiental , Férias e Feriados , Hidrocarbonetos Policíclicos Aromáticos/análise
8.
Adv Skin Wound Care ; 37(6): 319-327, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38767424

RESUMO

OBJECTIVE: To examine the factors influencing hospital discharge readiness among Chinese patients who have undergone enterostomy. METHODS: In this descriptive, cross-sectional study, researchers recruited patients with colorectal cancer who underwent enterostomy at a tertiary hospital in Guangdong Province, China, via convenience sampling between January 2021 and January 2023. Participants completed the Readiness for Hospital Discharge Scale, Ostomy Self-care Ability Scale, and Stoma-Quality of Life-Chinese Questionnaire (Chinese version) at the time of hospital discharge. Univariate, correlation, and multiple linear regression analyses were performed to explore the impact of self-care ability, quality of life, and other clinicodemographic characteristics on patients' readiness for hospital discharge. RESULTS: Of the 200 questionnaires distributed, 177 (88.5%) were completed and included in the final analysis. The median scores for the factors considered in this study were as follows: Readiness for Hospital Discharge Scale was 148.00 (interquartile range [IQR], 117.50, 164.00), self-care intention of the Ostomy Self-care Ability Scale was 36.00 (IQR, 34.00, 40.00), self-care knowledge of the Ostomy Self-care Ability Scale was 17.00 (IQR, 15.00, 19.00), self-care skill of the Ostomy Self-care Ability Scale was 5.00 (IQR, 3.00, 6.00), and the total score for quality of life was 60.00 (IQR, 49.00, 69.00). Multiple linear regression analysis identified several key factors explaining 48.2% of the variance in global readiness for hospital discharge: global quality of life (ß = .347, P < .001), self-care knowledge (ß = .259, P < .001), leakage during hospitalization (ß = -0.241, P < .001), monthly family income (ß = .148, P = .008), stoma siting before surgery (ß = .130, P = .020), and self-care intention (ß = .127, P = .035). CONCLUSIONS: The readiness for hospital discharge among patients undergoing enterostomy in this study was high. Factors such as quality of life, self-care knowledge, leakage during hospitalization, monthly family income, stoma siting before surgery, and self-care intention after undergoing enterostomy influenced the patients' readiness for hospital discharge. Therefore, future studies should focus on developing interventions to enhance patients' readiness for hospital discharge.


Assuntos
Enterostomia , Alta do Paciente , Qualidade de Vida , Autocuidado , Humanos , Estudos Transversais , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Qualidade de Vida/psicologia , China , Inquéritos e Questionários , Autocuidado/métodos , Adulto , Neoplasias Colorretais/cirurgia
9.
Technol Cancer Res Treat ; 23: 15330338241256814, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38773777

RESUMO

Objective: This prospective study aims to evaluate acute irradiation-induced xerostomia during radiotherapy by utilizing the normalized iodine concentration (NIC) derived from energy spectrum computed tomography (CT) iodine maps. Methods: In this prospective study, we evaluated 28 patients diagnosed with nasopharyngeal carcinoma. At 4 distinct stages of radiotherapy (0, 10, 20, and 30 fractions), each patient underwent CT scans to generate iodine maps. The NIC of both the left and right parotid glands was obtained, with the NIC at the 0-fraction stage serving as the baseline measurement. After statistically comparing the NIC obtained in the arterial phase, early venous phase, late venous phase, and delayed phase, we chose the late venous iodine concentration as the NIC and proceeded to analyze the variations in NIC at each radiotherapy interval. Using the series of NIC values, we conducted hypothesis tests to evaluate the extent of change in NIC within the parotid gland across different stages. Furthermore, we identified the specific time point at which the NIC decay exhibited the most statistically significant results. In addition, we evaluated the xerostomia grades of the patients at these 4 stages, following the radiation therapy oncology group (RTOG) xerostomia evaluation standard, to draw comparisons with the changes observed in NIC. Results: The NIC in the late venous phase exhibited the highest level of statistical significance (P < .001). There was a noticeable attenuation in NIC as the RTOG dry mouth grade increased. Particularly, at the 20 fraction, the NIC experienced the most substantial attenuation (P < .001), a significant negative correlation was observed between the NIC of the left, right, and both parotid glands, and the RTOG evaluation grade of acute irradiation-induced xerostomia (P < .001, r = -0.46; P < .001, r = -0.45; P < .001, r = -0.47). The critical NIC values for the left, right, and both parotid glands when acute xerostomia occurred were 0.175, 0.185, and 0.345 mg/ml, respectively, with AUC = 0.73, AUC = 0.75, and AUC = 0.75. Conclusion: The NIC may be used to evaluate changes in parotid gland function during radiotherapy and acute irradiation-induced xerostomia.


Assuntos
Iodo , Carcinoma Nasofaríngeo , Neoplasias Nasofaríngeas , Glândula Parótida , Tomografia Computadorizada por Raios X , Xerostomia , Humanos , Xerostomia/etiologia , Masculino , Glândula Parótida/efeitos da radiação , Feminino , Carcinoma Nasofaríngeo/radioterapia , Pessoa de Meia-Idade , Adulto , Idoso , Neoplasias Nasofaríngeas/radioterapia , Estudos Prospectivos , Lesões por Radiação/etiologia , Lesões por Radiação/diagnóstico , Dosagem Radioterapêutica
10.
Bioengineering (Basel) ; 11(5)2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38790385

RESUMO

A novel H-shaped miniplate (HSM) was specifically designed for restorative laminoplasties to restore patients' posterior elements after laminectomies. A validated finite element (FE) model of L2/4 was utilized to create a laminectomy model, as well as three restorative laminoplasty models based on the fixation of different miniplates after a laminectomy (the RL-HSM model, the RL-LSM model, and the RL-THM model). The biomechanical effects of motion and displacement on a laminectomy and restorative laminoplasty with three different shapes for the fixation of miniplates were compared under the same mechanical conditions. This study aimed to validate the biomechanical stability, efficacy, and feasibility of a restorative laminoplasty with the fixation of miniplates post laminectomy. The laminectomy model demonstrated the greatest increase in motion and displacement, especially in axial rotation, followed by extension, flexion, and lateral bending. The restorative laminoplasty was exceptional in preserving the motion and displacement of surgical segments when compared to the intact state. This preservation was particularly evident in lateral bending and flexion/extension, with a slight maintenance efficacy observed in axial rotation. Compared to the laminectomy model, the restorative laminoplasties with the investigated miniplates demonstrated a motion-limiting effect for all directions and resulted in excellent stability levels under axial rotation and flexion/extension. The greatest reduction in motion and displacement was observed in the RL-HSM model, followed by the RL-LSM model and then the RL-THM model. When comparing the fixation of different miniplates in restorative laminoplasties, the HSMs were found to be superior to the LSMs and THMs in maintaining postoperative stability, particularly in axial rotation. The evidence suggests that a restorative laminoplasty with the fixation of miniplates is more effective than a conventional laminectomy due to the biomechanical effects of restoring posterior elements, which helps patients regain motion and limit load displacement responses in the spine after surgery, especially in axial rotation and flexion/extension. Additionally, our evaluation in this research study could benefit from further research and provide a methodological and modeling basis for the design and optimization of restorative laminoplasties.

11.
Neural Regen Res ; 19(12): 2723-2734, 2024 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38595290

RESUMO

JOURNAL/nrgr/04.03/01300535-202412000-00028/figure1/v/2024-04-08T165401Z/r/image-tiff Immune changes and inflammatory responses have been identified as central events in the pathological process of spinal cord injury. They can greatly affect nerve regeneration and functional recovery. However, there is still limited understanding of the peripheral immune inflammatory response in spinal cord injury. In this study, we obtained microRNA expression profiles from the peripheral blood of patients with spinal cord injury using high-throughput sequencing. We also obtained the mRNA expression profile of spinal cord injury patients from the Gene Expression Omnibus (GEO) database (GSE151371). We identified 54 differentially expressed microRNAs and 1656 differentially expressed genes using bioinformatics approaches. Functional enrichment analysis revealed that various common immune and inflammation-related signaling pathways, such as neutrophil extracellular trap formation pathway, T cell receptor signaling pathway, and nuclear factor-κB signal pathway, were abnormally activated or inhibited in spinal cord injury patient samples. We applied an integrated strategy that combines weighted gene co-expression network analysis, LASSO logistic regression, and SVM-RFE algorithm and identified three biomarkers associated with spinal cord injury: ANO10, BST1, and ZFP36L2. We verified the expression levels and diagnostic performance of these three genes in the original training dataset and clinical samples through the receiver operating characteristic curve. Quantitative polymerase chain reaction results showed that ANO10 and BST1 mRNA levels were increased and ZFP36L2 mRNA was decreased in the peripheral blood of spinal cord injury patients. We also constructed a small RNA-mRNA interaction network using Cytoscape. Additionally, we evaluated the proportion of 22 types of immune cells in the peripheral blood of spinal cord injury patients using the CIBERSORT tool. The proportions of naïve B cells, plasma cells, monocytes, and neutrophils were increased while the proportions of memory B cells, CD8+ T cells, resting natural killer cells, resting dendritic cells, and eosinophils were markedly decreased in spinal cord injury patients increased compared with healthy subjects, and ANO10, BST1 and ZFP26L2 were closely related to the proportion of certain immune cell types. The findings from this study provide new directions for the development of treatment strategies related to immune inflammation in spinal cord injury and suggest that ANO10, BST1, and ZFP36L2 are potential biomarkers for spinal cord injury. The study was registered in the Chinese Clinical Trial Registry (registration No. ChiCTR2200066985, December 12, 2022).

12.
Artigo em Inglês | MEDLINE | ID: mdl-38607749

RESUMO

BACKGROUND: After undergoing fibula-free flap harvest, patients may experience complications such as ankle instability. It remains unclear whether these patients have deficits of proprioception, and the recovery process is also uncertain. OBJECTIVE: This study aimed to objectively evaluate proprioception on the donor and normal side of surgical patients during long-term follow-up using the Pro-kin system. METHODS: This study enrolled 36 patients who underwent reconstruction of the head and neck using osseous free flaps harvested from the fibula. Each patient underwent pre-operative evaluations and was subsequently evaluated at postoperative months 1, 3, 6, and 12. The study assessed the proprioceptive evaluation of the lower limbs, muscle function, range of motion of the ankle, and donor side complications. RESULTS: On the donor side, the average trace error (ATE) at postoperative month 1 was significantly higher than pre-operation, postoperative months 6 and 12 (P< 0.05). The test execution time (TTE) at postoperative month 1 was significantly increased by 9.875s compared to the pre-operative levels (P= 0.012, 95% confidence interval [CI] 4: 1.877-17.873) and by 11.583s compared to postoperative month 12 (P= 0.007, 95% CI: 2.858-20.309). The reduction in range of motion of ankle dorsiflexion was most pronounced at postoperative month 1, exhibiting an 11.25∘ decrease compared to pre-operative levels (P< 0.001, 95% CI: 6.304-16.16). Although the range of motion of ankle dorsiflexion gradually improved over time at postoperative months 3, 6, and 12, it remained lower than pre-operative levels (P< 0.05). CONCLUSION: The study revealed that the patients exhibited proprioceptive disturbances in both lower limbs at postoperative month 1. The proprioceptive function gradually improved over time, with a gradual decrease in donor site complications.

13.
Environ Sci Technol ; 58(17): 7516-7528, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38629947

RESUMO

Field observations of daytime HONO source strengths have not been well explained by laboratory measurements and model predictions up until now. More efforts are urgently needed to fill the knowledge gaps concerning how environmental factors, especially relative humidity (RH), affect particulate nitrate photolysis. In this work, two critical attributes for atmospheric particles, i.e., phase state and bulk-phase acidity, both influenced by ambient RH, were focused to illuminate the key regulators for reactive nitrogen production from typical internally mixed systems, i.e., NaNO3 and dicarboxylic acid (DCA) mixtures. The dissolution of only few oxalic acid (OA) crystals resulted in a remarkable 50-fold increase in HONO production compared to pure nitrate photolysis at 85% RH. Furthermore, the HONO production rates (PHONO) increased by about 1 order of magnitude as RH rose from <5% to 95%, initially exhibiting an almost linear dependence on the amount of surface absorbed water and subsequently showing a substantial increase in PHONO once nitrate deliquescence occurred at approximately 75% RH. NaNO3/malonic acid (MA) and NaNO3/succinic acid (SA) mixtures exhibited similar phase state effects on the photochemical HONO production. These results offer a new perspective on how aerosol physicochemical properties influence particulate nitrate photolysis in the atmosphere.


Assuntos
Nitratos , Fotólise , Nitratos/química , Ácidos Dicarboxílicos/química , Ácido Nitroso/química , Umidade , Malonatos/química , Poluentes Atmosféricos/química
14.
Environ Sci Technol ; 58(15): 6736-6743, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38564367

RESUMO

Acidity is an important property of particulate matter (PM) in the atmosphere, but its association with PM toxicity remains unclear. Here, this study quantitively reports the effect of the acidity level on PM toxicity via pH-control experiments and cellular analysis. Oxidative stress and cytotoxicity potencies of acidified PM samples at pH of 1-2 were up to 2.8-5.2 and 2.1-13.2 times higher than those at pH of 8-11, respectively. The toxic potencies of PM samples from real-world smoke plumes at the pH of 2.3 were 9.1-18.2 times greater than those at the pH of 5.6, demonstrating a trend similar to that of acidified PM samples. Furthermore, the impact of acidity on PM toxicity was manifested by promoting metal dissolution. The dramatic increase by 2-3 orders of magnitude in water-soluble metal content dominated the variation in PM toxicity. The significant correlation between sulfate, the pH value, water-soluble Fe, IC20, and EC1.5 (p < 0.05) suggested that acidic sulfate could enhance toxic potencies by dissolving insoluble metals. The findings uncover the superficial association between sulfate and adverse health outcomes in epidemiological research and highlight the control of wet smoke plume emissions to mitigate the toxicity effects of acidity.


Assuntos
Poluentes Atmosféricos , Material Particulado , Material Particulado/análise , Poluentes Atmosféricos/toxicidade , Poluentes Atmosféricos/análise , Metais/toxicidade , Metais/análise , Fumaça/análise , Sulfatos/análise , Água , Monitoramento Ambiental
15.
Lipids Health Dis ; 23(1): 92, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38561841

RESUMO

BACKGROUND: Lipoprotein lipase (LPL) plays a crucial role in triglyceride hydrolysis. Rare biallelic variants in the LPL gene leading to complete or near-complete loss of function cause autosomal recessive familial chylomicronemia syndrome. However, rare biallelic LPL variants resulting in significant but partial loss of function are rarely documented. This study reports a novel occurrence of such rare biallelic LPL variants in a Chinese patient with hypertriglyceridemia-induced acute pancreatitis (HTG-AP) during pregnancy and provides an in-depth functional characterization. METHODS: The complete coding sequences and adjacent intronic regions of the LPL, APOC2, APOA5, LMF1, and GPIHBP1 genes were analyzed by Sanger sequencing. The aim was to identify rare variants, including nonsense, frameshift, missense, small in-frame deletions or insertions, and canonical splice site mutations. The functional impact of identified LPL missense variants on protein expression, secretion, and activity was assessed in HEK293T cells through single and co-transfection experiments, with and without heparin treatment. RESULTS: Two rare LPL missense variants were identified in the patient: the previously reported c.809G > A (p.Arg270His) and a novel c.331G > C (p.Val111Leu). Genetic testing confirmed these variants were inherited biallelically. Functional analysis showed that the p.Arg270His variant resulted in a near-complete loss of LPL function due to effects on protein synthesis/stability, secretion, and enzymatic activity. In contrast, the p.Val111Leu variant retained approximately 32.3% of wild-type activity, without impacting protein synthesis, stability, or secretion. Co-transfection experiments indicated a combined activity level of 20.7%, suggesting no dominant negative interaction between the variants. The patient's post-heparin plasma LPL activity was about 35% of control levels. CONCLUSIONS: This study presents a novel case of partial but significant loss-of-function biallelic LPL variants in a patient with HTG-AP during pregnancy. Our findings enhance the understanding of the nuanced relationship between LPL genotypes and clinical phenotypes, highlighting the importance of residual LPL function in disease manifestation and severity. Additionally, our study underscores the challenges in classifying partial loss-of-function variants in classical Mendelian disease genes according to the American College of Medical Genetics and Genomics (ACMG)'s variant classification guidelines.


Assuntos
Hiperlipidemias , Hipertrigliceridemia , Pancreatite , Humanos , Lipase Lipoproteica/genética , Doença Aguda , Células HEK293 , Pancreatite/genética , Heparina
16.
Environ Sci Technol ; 58(19): 8194-8206, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38683689

RESUMO

Phenolic compounds are largely emitted from biomass burning (BB) and have a significant potential to form SOA (Phc-SOA). However, the toxicological properties of Phc-SOA remain unclear. In this study, phenol and guaiacol were chosen as two representative phenolic gases in BB plumes, and the toxicological properties of water-soluble components of their SOA generated under different photochemical ages and NOx levels were investigated. Phenolic compounds contribute greatly to the oxidative potential (OP) of biomass-burning SOA. OH-adducts of guaiacol (e.g., 2-methoxyhydroquinone) were identified as components of guaiacol SOA (GSOA) with high OP. The addition of nitro groups to 2,5-dimethyl-1,4-benzoquinone, a surrogate quinone compound in Phc-SOA, increased its OP. The toxicity of both phenol SOA (PSOA) and GSOA in vitro in human alveolar epithelial cells decreased with aging in terms of both cell death and cellular reactive oxygen species (ROS), possibly due to more ring-opening products with relatively low toxicity. The influence of NOx was consistent between cell death and cellular ROS for GSOA but not for PSOA, indicating that cellular ROS production does not necessarily represent all processes contributing to cell death caused by PSOA. Combining different acellular and cellular assays can provide a comprehensive understanding of aerosol toxicological properties.


Assuntos
Aerossóis , Biomassa , Fenóis , Espécies Reativas de Oxigênio , Espécies Reativas de Oxigênio/metabolismo , Fenóis/toxicidade , Humanos , Oxirredução , Poluentes Atmosféricos/toxicidade
17.
BMC Med Educ ; 24(1): 473, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38685015

RESUMO

BACKGROUND: Studies has suggested that receiving social support improves the professional identity of health professional students. According to the two-way social support theory, social support includes receiving social support and giving social support. However, the effect of the two-way social support on health professional students' professional identity has not been clarified yet. METHODS: To explore the mechanism of how two-way social support affects health professional students' professional identity, an observational, cross-sectional study was conducted among a convenience and cluster sample of 1449 health professional students from two medical schools in western China. Measures included a short version of the two-way social support scale, a health professional students' professional identity questionnaire, an achievement motivation scale, and a meaning in life scale. Data were analyzed by use of SPSS26.0 software and PROCESSv4.0 plug-in. RESULTS: Receiving social support, giving social support, achievement motivation, meaning in life, and professional identity were positively correlated with each other. Receiving and giving social support not only directly predicted health professional students' professional identity, but also indirectly predicted health professional students' professional identity through the mediating roles of achievement motivation and meaning in life, and the chain mediating roles of achievement motivation and meaning in life, respectively. The effectiveness of predicting health professional students' professional identity varied among different types of two-way social support, which could be depicted as two-way social support > mainly giving social support > mainly receiving social support > low two-way social support. CONCLUSION: In the medical education, the awareness and ability of health professional students to receive and give social support should be strengthened. More attention should be drawn on the chain mediating effect of achievement motivation and meaning in life between two-way social support and professional identity. The current results shed new light on exploring effective ways of improving health professional students' professional identity, which suggested that more attention should be paid to the positive effects of mainly giving social support and two-way social support rather than only on the effects of receiving social support.


Assuntos
Motivação , Identificação Social , Apoio Social , Humanos , Estudos Transversais , Masculino , Feminino , Adulto Jovem , China , Estudantes de Medicina/psicologia , Adulto , Inquéritos e Questionários , Estudantes de Ciências da Saúde/psicologia
18.
PeerJ ; 12: e16985, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38436009

RESUMO

Tillering/branching pattern plays a significant role in determining the structure and diversity of grass, and trimming has been found to induce tillering in turfgrass. Recently, it has been reported that hydrogen peroxide (H2O2) regulates axillary bud development. However, the role of H2O2 in trimming-induced tillering in bermudagrass, a kind of turfgrass, remains unclear. Our study unveils the significant impact of trimming on promoting the sprouting and growth of tiller buds in stolon nodes, along with an increase in the number of tillers in the main stem. This effect is accompanied by spatial-temporal changes in cytokinin and sucrose content, as well as relevant gene expression in axillary buds. In addition, the partial trimming of new-born tillers results in an increase in sucrose and starch reserves in their leaves, which can be attributed to the enhanced photosynthesis capacity. Importantly, trimming promotes a rapid H2O2 burst in the leaves of new-born tillers and axillary stolon buds. Furthermore, exogenous application of H2O2 significantly increases the number of tillers after trimming by affecting the expression of cytokinin-related genes, bolstering photosynthesis potential, energy reserves and antioxidant enzyme activity. Taken together, these results indicate that both endogenous production and exogenous addition of H2O2 enhance the inductive effects of trimming on the tillering process in bermudagrass, thus helping boost energy supply and maintain the redox state in newly formed tillers.


Assuntos
Cynodon , Peróxido de Hidrogênio , Oxirredução , Antioxidantes , Citocininas , Sacarose
19.
J Am Chem Soc ; 146(10): 6580-6590, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38427385

RESUMO

The multiphase oxidation of sulfur dioxide (SO2) to form sulfate is a complex and important process in the atmosphere. While the conventional photosensitized reaction mainly explored in the bulk medium is reported to be one of the drivers to trigger atmospheric sulfate production, how this scheme functionalizes at the air-water interface (AWI) of aerosol remains an open question. Herein, employing an advanced size-controllable microdroplet-printing device, surface-enhanced Raman scattering (SERS) analysis, nanosecond transient adsorption spectrometer, and molecular level theoretical calculations, we revealed the previously overlooked interfacial role in photosensitized oxidation of SO2 in humic-like substance (HULIS) aerosol, where a 3-4 orders of magnitude increase in sulfate formation rate was speculated in cloud and aerosol relevant-sized particles relative to the conventional bulk-phase medium. The rapid formation of a battery of reactive oxygen species (ROS) comes from the accelerated electron transfer process at the AWI, where the excited triplet state of HULIS (3HULIS*) of the incomplete solvent cage can readily capture electrons from HSO3- in a way that is more efficient than that in the bulk medium fully blocked by water molecules. This phenomenon could be explained by the significantly reduced desolvation energy barrier required for reagents residing in the AWI region with an open solvent shell.

20.
Pancreatology ; 24(4): 511-521, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38485544

RESUMO

BACKGROUND & AIMS: Protease-sensitive PNLIP variants were recently associated with chronic pancreatitis (CP) in European populations. The pathological mechanism yet remains elusive. Herein, we performed a comprehensive genetic and functional analysis of PNLIP variants found in a large Chinese cohort, aiming to further unravel the enigmatic association of PNLIP variants with CP. METHODS: All coding and flanking intronic regions of the PNLIP gene were analyzed for rare variants by targeted next-generation sequencing in 1082 Chinese CP patients and 1196 controls. All novel missense variants were subject to analysis of secretion, lipase activity, and proteolytic degradation. One variant was further analyzed for its potential to misfold and induce endoplasmic reticulum (ER) stress. p.F300L, the most common PNLIP variant associated with CP, was used as a control. RESULTS: We identified 12 rare heterozygous PNLIP variants, with 10 being novel. The variant carrier frequency did not differ between the groups. Of them, only the variant p.A433T found in a single patient was considered pathologically relevant. p.A433T exhibited increased susceptibility to proteolytic degradation, which was much milder than p.F300L. Interestingly, both variants exhibited an increased tendency to misfold, leading to intracellular retention as insoluble aggregates, reduced secretion, and elevated ER stress. CONCLUSIONS: Our genetic and functional analysis of PNLIP variants identified in a Chinese CP cohort suggests that the p.A433T variant and the previously identified p.F300L variant are not only protease-sensitive but also may be potentially proteotoxic. Mouse studies of the PNLIP p.F300L and p.A433T variants are needed to clarify their role in CP.


Assuntos
Povo Asiático , Predisposição Genética para Doença , Pancreatite Crônica , Humanos , Pancreatite Crônica/genética , Masculino , Povo Asiático/genética , Feminino , Estudos de Coortes , Pessoa de Meia-Idade , Adulto , Lipase/genética , Estresse do Retículo Endoplasmático/genética , China/epidemiologia , Mutação de Sentido Incorreto , Idoso , Variação Genética , População do Leste Asiático
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