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1.
J Environ Sci (China) ; 148: 107-115, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095149

RESUMO

The evaluation of toxicity related to polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) and dioxin-like polychlorinated biphenyls (DL-PCBs) is crucial for a comprehensive risk assessment in real-world exposure scenarios. This study employed a controlled feeding experiment to investigate the metabolic effects of dioxin-like compounds (DLCs) on laying hens via feed exposure. Diets enriched with two concentrations (1.17 and 5.13 pg toxic equivalents (TEQ)/g dry weight (dw)) were administered over 14 days, followed by 28 days of clean feed. Metabolomics analyses of blood samples revealed significant metabolic variations between PCDD/Fs and DL-PCBs exposed groups and controls, reflecting the induced metabolic disruption. Distinct changes were observed in sphingosine, palmitoleic acid, linoleate, linolenic acid, taurocholic acid, indole acrylic acid, and dibutyl phthalate levels, implying possible connections between PCDD/Fs and DL-PCBs toxic effects and energy-neuronal imbalances, along with lipid accumulation and anomalous amino acid metabolism, impacting taurine metabolism. Moreover, we identified three differential endogenous metabolites-L-tryptophan, indole-3-acetaldehyde, and indole acrylic acid-as potential ligands for the aryl hydrocarbon receptor (AhR), suggesting their role in mediating PCDD/Fs and DL-PCBs toxicity. This comprehensive investigation provides novel insights into the metabolic alterations induced by PCDD/Fs and DL-PCBs in laying hens, thereby enhancing our ability to assess risks associated with their exposure in human populations.


Assuntos
Galinhas , Animais , Dioxinas e Compostos Semelhantes a Dioxinas/metabolismo , Dioxinas e Compostos Semelhantes a Dioxinas/toxicidade , Feminino , Poluentes Ambientais/toxicidade , Poluentes Ambientais/metabolismo , Bifenilos Policlorados/toxicidade , Metabolômica , Metaboloma/efeitos dos fármacos , Ração Animal/análise , Dibenzodioxinas Policloradas/toxicidade
2.
Environ Pollut ; 361: 124882, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-39241952

RESUMO

Historical chlor-alkali production has led to substantial concentrations of persistent organic pollutant residues in the environment. This study systematically investigated the distribution of polycyclic aromatic hydrocarbons (PAHs), chlorinated/brominated-PAHs (Cl/Br-PAHs), polychlorinated naphthalenes (PCNs), and hexachlorobutadiene (HCBD) in sediment, lotus (Nelumbo nucifera), and fish samples from Ya-Er Lake, which is a site in China with historical chlor-alkali contamination. The average concentrations [(4.97-1.47) × 103 ng/g dry weight (dw)] of these pollutants in backfill sediments, which were dredged from the lake after chlor-alkali production stopped, were 2.68-70.87 times those in fresh lake sediments (0.622-218 ng/g dw) and reported concentrations in other areas. Correlation analyses indicated that Cl-PAHs, Br-PAHs, and PCNs likely originated from halogenation of parent PAHs in the study area, and the chlorination ratios were larger than those of bromination. The Cl(1/2/3)-PAHs/PAHs and Br(1)-PAHs/PAHs ratios were higher than those for PAHs with more halogen atoms. This contamination extended into the biota, with notable pollutant burdens found in lotus (Nelumbo nucifera, 0.305-77.3 ng/g dw) and even higher concentrations in fish (2.20-345 ng/g lipid weight). Estimated biological soil accumulation factors revealed significant enrichment in lotus organs (mean: 7.19) and fish muscle (mean: 10.65), especially the latter, which highlighted bioaccumulation and potential food chain transfer risks. The estimated daily intakes of PAHs, Cl/Br-PAHs, and HCBD through fish consumption currently pose negligible risks, while dietary intake of PCNs may present health concerns. Continuous monitoring and impact assessments are crucial for developing appropriate risk management strategies to safeguard public health.

3.
Neurosci Biobehav Rev ; 165: 105868, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39218048

RESUMO

As a central molecule in complement system (CS), complement (C) 3 is upregulated in the patients and animal models of Alzheimer's disease (AD). C3 will metabolize to iC3b and C3a. iC3b is responsible for clearing ß-amyloid protein (Aß). In this scenario, C3 exerts neuroprotective effects against the disease via iC3b. However, C3a will inhibit microglia to clear the Aß, leading to the deposition of Aß and impair the functions of synapses. To their effects on AD, activation of C3a and C3a receptor (C3aR) will impair the mitochondria, leading to the release of reactive oxygen species (ROS), which activates the NOD-like receptor thermal protein domain associated protein 3 (NLRP3) inflammasomes. The overloading of NLRP3 inflammasomes activate microglia, leading to the formation of inflammatory environment. The inflammatory environment will facilitate the deposition of Aß and abnormal synapse pruning, which results in the progression of AD. Therefore, the current review will decipher the mechanisms of C3a inducing the synapse loss via C3aR in mitochondria-dependent NLRP3 activating mechanisms, which facilitates the understanding the AD.


Assuntos
Doença de Alzheimer , Complemento C3a , Mitocôndrias , Proteína 3 que Contém Domínio de Pirina da Família NLR , Receptores de Complemento , Sinapses , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Humanos , Sinapses/metabolismo , Sinapses/patologia , Animais , Mitocôndrias/metabolismo , Receptores de Complemento/metabolismo , Complemento C3a/metabolismo , Progressão da Doença , Complemento C3/metabolismo
4.
EClinicalMedicine ; 75: 102791, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39286636

RESUMO

Background: This was a multicenter, single-arm dose-ranging phase 2 study aimed to assess the efficacy and safety of LY01610, a liposomal irinotecan, at various doses for patients with relapsed small cell lung cancer (SCLC). Methods: This study (NCT04381910) enrolled patients with relapsed SCLC at 10 hospitals across China, who have failed with previous platinum-based treatments. LY01610 was administered at doses of 60 mg/m2, 80 mg/m2, and 100 mg/m2. Primary endpoints were investigator-assessed objective response rate (ORR) and investigator-assessed duration of response (DoR). Secondary endpoints included investigator-assessed disease control rate (DCR), investigator-assessed progression-free survival (PFS), overall survival (OS), and safety. Findings: From September 3, 2020 to March 3, 2022, a total of 66 patients were enrolled, with 6, 30, and 30 allocated to the 60 mg/m2, 80 mg/m2, and 100 mg/m2 dose groups, respectively, with 68% (45/66) having a chemotherapy-free interval <90 days. In all 66 patients, the ORR was 32% (21/66, 95% confidence interval [CI], 21-44), with a median DoR of 5.2 months (95% CI, 3.0-8.3). Median PFS and OS were 4.0 (95% CI, 2.9-5.5) and 9.7 (95% CI, 7.2-12.3) months, respectively. The ORR of 60 mg/m2, 80 mg/m2, and 100 mg/m2 dose group were 33% (2/6), 33% (10/30), and 30% (9/30), respectively. The median DoR of 60 mg/m2, 80 mg/m2, and 100 mg/m2 dose group were 4.2 (95% CI, 2.8-not reached), 6.9 (95% CI, 2.5-9.9), and 4.0 (95% CI, 2.7-6.8) months, respectively. The incidence of ≥ grade 3 treatment-related adverse events (TRAEs) in the 60 mg/m2, 80 mg/m2, and 100 mg/m2 dose group were 33% (2/6), 47% (14/30), and 50% (15/30), respectively. The most common ≥ grade 3 TRAEs of all 66 patients were neutropenia (27%), leukopenia (24%) and anemia (15%). Interpretation: LY01610 exhibited promising clinical efficacy and manageable safety profiles in patients with relapsed SCLC, the 80 mg/m2 dose group had the best benefit-risk ratio. Funding: This study was supported by Luye Pharma Group Ltd.

6.
PeerJ ; 12: e17776, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39224820

RESUMO

Background: The tcdA gene codes for an important toxin produced by Clostridioides difficile (C. difficile), but there is currently no simple and cost-effective method of detecting it. This article establishes and validates a rapid and visual loop-mediated isothermal amplification (LAMP) assay for the detection of the tcdA gene. Methods: Three sets of primers were designed and optimized to amplify the tcdA gene in C. difficile using a LAMP assay. To evaluate the specificity of the LAMP assay, C. difficile VPI10463 was used as a positive control, while 26 pathogenic bacterial strains lacking the tcdA gene and distilled water were utilized as negative controls. For sensitivity analysis, the LAMP assay was compared to PCR using ten-fold serial dilutions of DNA from C. difficile VPI10463, ranging from 207 ng/µl to 0.000207 pg/µl. The tcdA gene of C.difficile was detected in 164 stool specimens using both LAMP and polymerase chain reaction (PCR). Positive and negative results were distinguished using real-time monitoring of turbidity and chromogenic reaction. Results: At a temperature of 66 °C, the target DNA was successfully amplified with a set of primers designated, and visualized within 60 min. Under the same conditions, the target DNA was not amplified with the tcdA12 primers for 26 pathogenic bacterial strains that do not carry the tcdA gene. The detection limit of LAMP was 20.700 pg/µl, which was 10 times more sensitive than that of conventional PCR. The detection rate of tcdA in 164 stool specimens using the LAMP method was 17% (28/164), significantly higher than the 10% (16/164) detection rate of the PCR method (X2 = 47, p < 0.01). Conclusion: LAMP method is an effective technique for the rapid and visual detection of the tcdA gene of C. difficile, and shows potential advantages over PCR in terms of speed, simplicity, and sensitivity. The tcdA-LAMP assay is particularly suitable for medical diagnostic environments with limited resources and is a promising diagnostic strategy for the screening and detection of C. difficile infection in populations at high risk.


Assuntos
Toxinas Bacterianas , Clostridioides difficile , Infecções por Clostridium , Enterotoxinas , Fezes , Técnicas de Amplificação de Ácido Nucleico , Sensibilidade e Especificidade , Clostridioides difficile/genética , Clostridioides difficile/isolamento & purificação , Técnicas de Amplificação de Ácido Nucleico/métodos , Humanos , Toxinas Bacterianas/genética , Infecções por Clostridium/diagnóstico , Infecções por Clostridium/microbiologia , Fezes/microbiologia , Fezes/química , Enterotoxinas/genética , Primers do DNA/genética , Técnicas de Diagnóstico Molecular/métodos , Reação em Cadeia da Polimerase/métodos , Adulto , Pessoa de Meia-Idade
7.
J Phys Chem Lett ; 15(36): 9216-9225, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39225489

RESUMO

Gold nanoclusters are ideal fluorescent labels for biological imaging, disease diagnosis, and treatment. Understanding the origin of the photoluminescence phenomenon in ligand-protected gold nanoclusters is crucial for both basic science and practical applications. In this study, density functional theory (DFT) and time-dependent DFT (TD-DFT) calculations were performed to study the mechanism of excited state deactivation of Au38S2(S-Adm)20 and Au30(S-Adm)18 (S-Adm = adamantanethiolate) clusters, which have similar sizes and compositions. The computational results indicate that the differences in structural symmetry and peripheral ligand layer lead to quite different excited state deactivation mechanisms and excited state lifetimes in Au38S2(S-Adm)20 and Au30(S-Adm)18. Specifically, the µ3-S atoms and bridging thiolate (SR) in the ligand layer of Au38S2(S-Adm)20 significantly suppress the structural relaxation of ligand motifs, resulting in a prolonged excited state lifetime and higher quantum yield. For the Au30(S-Adm)18, due to the symmetry forbidden and large structural relaxation of the ligand shell, a rapid nonradiative transition process resulted. This study provides new insights into how the photoluminescence of ligand-protected gold nanoclusters is influenced by their structure and symmetry.

8.
Sci Total Environ ; 953: 176095, 2024 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-39245376

RESUMO

Perfluoroalkyl and polyfluoroalkyl substances (PFAS) are widely used across a spectrum of industrial and consumer goods. Nonetheless, their persistent nature and tendency to accumulate in biological systems pose substantial environmental and health threats. Consequently, striking a balance between maximizing product efficiency and minimizing environmental and health risks by tailoring the molecular structure of PFAS has become a pivotal challenge in the fields of environmental chemistry and sustainable development. To address this issue, a computational workflow was proposed for designing an environmentally friendly PFAS by incorporating deep learning (DL) and molecular generative models. The hybrid DL architecture MolHGT+ based on heterogeneous graph neural network with transformer-like attention was applied to predict the surface tension, bioaccumulation, and hepatotoxicity of the molecules. Through virtual screening of the PFAS master database using MolHGT+, the findings indicate that incorporating the siloxane group and betaine fragment can effectively decrease both the bioaccumulation and hepatotoxicity of PFAS while preserving low surface tension. In addition, molecular generative models were employed to create a structurally diverse pool of novel PFASs with the aforementioned hit molecules serving as the initial template structures. Overall, our study presents a promising AI-driven method for advancing the development of environmentally friendly PFAS.

9.
J Int Med Res ; 52(9): 3000605241274236, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39246066

RESUMO

OBJECTIVE: In this study, we aimed to explore the potential association between COVID-19 infection, hospitalization, severe COVID-19, and erection dysfunction (ED) using the two-sample Mendelian randomization (MR) method. METHODS: Data pertaining to COVID-19 were extracted from the latest version of the COVID-19 Host Genetics Initiative genome-wide association study (GWAS) meta-analyses (Round 7, April 2022), and outcome data were obtained from the Open GWAS database. We applied various MR analysis methods, including the inverse variance weighted method, weighted median method, and MR-Egger regression. RESULTS: Our investigation revealed a negative causal association between COVID-19 hospitalization and ED (total testosterone levels: beta = -0.026; 95% confidence interval: -0.049 to -0.001). However, no evidence supported causal relationships between COVID-19 infection, hospitalization for COVID-19, or severe COVID-19 and other ED risk factors. CONCLUSION: The results of this comprehensive MR analysis suggest a negative causal link between COVID-19 hospitalization and total testosterone levels. Nonetheless, COVID-19 (comprising infection, hospitalization, and severe illness) may not directly correlate with an increased risk of ED. These findings imply that COVID-19 may exert a distinct impact on ED through indirect pathways.


Assuntos
COVID-19 , Disfunção Erétil , Estudo de Associação Genômica Ampla , Hospitalização , Análise da Randomização Mendeliana , SARS-CoV-2 , Testosterona , Humanos , COVID-19/genética , COVID-19/complicações , COVID-19/virologia , Masculino , Disfunção Erétil/genética , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/genética , Testosterona/sangue , Fatores de Risco , Polimorfismo de Nucleotídeo Único
10.
Hum Immunol ; 85(6): 111092, 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39255559

RESUMO

PURPOSE: The objective of this research is to analyze the clinical progression and identify prognostic factors among elderly patients with sepsis admitted to the emergency intensive care unit (EICU). METHODS: A total of 211 patients with sepsis, aged 65 years or above, were selected for inclusion in the study. These patients were admitted to the EICU of the Emergency Department at Harrison International Peace Hospital Affiliated to Hebei Medical University from August 2018 to June 2023. The clinical features, Acute Physiology and Chronic Health Evaluation (APACHE) Π score, Sequential Organ Failure Assessment (SOFA) score, and routine laboratory test indicators were documented. All patients were followed up for 28 days. The factors associated with mortality in both the sepsis group and septic shock group were analyzed by receiver operating characteristic (ROC) curve, MedCalc software, and Kaplan-Meier curve. RESULTS: Among the 211 patients, 101 were identified as having septic shock. A significant elevation in blood urea nitrogen-to-albumin ratio (BAR) and inflammatory indicators, APACHE II score, and SOFA score was observed in the septic shock group compared to the sepsis group (P<0.001). Moreover, the sepsis group exhibited a higher proportion of males (P=0.002), while there was no statistically significant difference in age (P=0.467). Further analysis revealed that BAR within 24 h after admission exhibited a positive correlation with infection indicators procalcitonin (PCT) and C-reactive protein (CRP), as well as disease severity scores APACHE Π and SOFA. Additionally, BAR was found to be positively associated with the 28-day mortality rate in patients with sepsis (r = 0.169, P=0.001). The results of the ROC curve analysis showed that BAR exhibited the highest predictive capability for 28-day mortality in elderly patients with sepsis who were admitted to the EICU (AUC=0.614). The Kaplan-Meier survival curve, which identified the optimal cut-off value (≥0.3) of BAR as the most accurate predictor of 28-day mortality in this individual, revealed a significantly higher mortality rate among patients with BAR≥0.3 (χ2 = 12.340, P=0.000). CONCLUSION: The elderly patients with sepsis in the EICU are generally over the age of 70, with a higher prevalence of males than females, and the albumin level is generally low on admission. Furthermore, BAR is significantly and positively correlated with infectious indexes and has a high predictive value for their mortality outcomes.

11.
Int J Surg ; 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39116453

RESUMO

IMPORTANCE: Successful needle puncture of the renal collecting system is a critical but difficult procedure in percutaneous nephrolithotomy (PCNL). Although fluoroscopy and ultrasound are the standard imaging techniques to guide puncture during PCNL, both have known limitations. OBJECTIVE: To assess the feasibility and safety of a new navigation system for needle puncture in ultrasound-guided PCNL. DESIGN: This study employed a single-center randomized controlled trial (RCT) design to assess the feasibility and safety of a new navigation system for needle puncture in ultrasound-guided PCNL. Conducted between May 2021 and November 2021, the trial utilized computer-generated random numbers for participant allocation to control for selection bias. SETTING: The trial was executed at the *********, which serves as an academic medical center. PARTICIPANTS: All patients who met the inclusion criteria were randomly divided into two groups, with 29 patients in each group. One group underwent PCNL procedures using the new navigation system, while the control group underwent standard ultrasound-guided PCNL procedures. Included patients had renal pelvis or caliceal calculi larger than 2.0 cm in diameter or had multiple or staghorn stones. The puncture procedure was performed with the support of real-time ultrasound imaging and visual guidance displayed on the screen. MAIN OUTCOMES AND MEASURES: The primary outcome was system feasibility and puncture success rate. Secondary outcomes included puncture time, total surgical time, number of attempts, post-procedure complications, and one-year and three-year stone recurrence rates. Stone clearance was defined by postoperative CT. Descriptive statistics summarized patient demographics, stone size, and location. Independent samples t-tests analyzed puncture time and total surgical time. Chi-square or Fisher's exact tests compared stone clearance, complications, socioeconomic status, renal hydronephrosis, stone location, race, and medical history. Linear regression examined the correlation between BMI and puncture time. Significance was set at P<0.05. RESULTS: For all 58 patients undergoing PCNL, needle punctures of the renal collecting system were completed with a success rate of 100%. The average time from planning the puncture protocol to successful puncture was significantly shorter in the AcuSee guidance system group (3.12 min, range 0.2-6.88 min) compared to the standard ultrasound-guided group (7.58 min, range 5.41-10.68 min), representing a reduction of approximately 59%. The total surgical time was also shorter in the AcuSee group for patients with no and mild hydronephrosis (P<0.05). Complication rates were lower in the AcuSee group, with no major complications observed. However, 3 patients in the standard ultrasound-guided group have adverse effects after the PCNL procedure. The one-year stone recurrence rate was significantly lower in the AcuSee group (3.4%) compared to the standard group (24.1%), and the three-year recurrence rate was also lower (6.9% vs. 41.4%). Patient-specific factors such as BMI, renal morphology, and prior surgical history did not significantly affect the performance of the AcuSee system. CONCLUSIONS AND RELEVANCE: We report the first clinical application of a new navigation system for needle puncture in ultrasound-guided PCNL. It has been demonstrated that it is feasible and safe compared to the standard ultrasound-guided group in percutaneous renal puncture. This technology provides intuitive and easy-to-use visual guidance, which may facilitate safe, accurate and fast needle puncture of the kidney.

12.
Phys Rev Lett ; 133(3): 033202, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39094146

RESUMO

We conducted a joint theoretical and experimental study to investigate the collisional dissipation of molecular alignment. By comparing experimental measurements to the quantum simulations, the nonsecular effect in the collision dissipation of molecular alignment was unveiled from the gas-density-dependent decay rates of the molecular alignment revival signals. Different from the conventional perspective that the nonsecular collisional effect rapidly fades within the initial few picoseconds following laser excitation, our simulations of the time-dependent decoherence process demonstrated that this effect can last for tens of picoseconds in the low-pressure regime. This extended timescale allows for the distinct identification of the nonsecular effect from molecular alignment signals. Our findings present the pioneering evidence that nonsecular molecular collisional dissipation can endure over an extended temporal span, challenging established concepts and strengthening our understanding of molecular dynamics within dissipative environments.

13.
Angew Chem Int Ed Engl ; : e202409465, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39196822

RESUMO

Developing efficient electrocatalyst in sulfides for hydrogen evolution reaction (HER) still poses challenges due to the lack of understanding the role of sulfide heterointerface. Here, we report a sulfide heterostructure RuSx/NbS2, which is composed of 3R-type NbS2 loaded by amorphous RuSx nanoparticles with S-S bonds formed at the interface. As HER electrocatalyst, the RuSx/NbS2 shows remarkable low overpotential of 38 mV to drive a current density of 10 mA cm-2 in acid, and also low Tafel slope of 51.05 mV dec-1. The intrinsic activity of RuSx/NbS2 is much higher than that of Ru/NbS2 reference as well as the commercial Pt/C. Both experiments and theoretical calculations unveil a reversed charge transfer at the interface from NbS2 to RuSx that driven by the formation of S-S bonds, resulting in electron-rich Ru configuration for strong hydrogen adsorption. Meanwhile, electronic redistribution induced by the sulfide heterostructure facilitates hydrogen spillover (HSo) effect in this system, leading to accelerated hydrogen desorption at the basal plane of NbS2. This study provides an effective S-S bond strategy in sulfide heterostructure to synergistically modulate the charge transfer and adsorption thermodynamics, which is very valuable for the development of efficient electrocatalysts in practical applications.

14.
Anal Chim Acta ; 1323: 343077, 2024 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-39182976

RESUMO

BACKGROUND: Mercury (Hg), especially methylmercury (MeHg) as a most toxic format of Hg in the environment, has been paid widely concern due to its high bioaccumulative capability and great risk to humans. Great efforts have been made to develop ethylation-purge and trap-gas chromatography-inductively coupled plasma mass spectrometry system for MeHg analysis and Hg biogeochemical cycling investigation. However, the generally manual operation limits the analytical efficiency, and the lack of applications in the real environmental samples restricts the future study. There is a great need for a rapid and accurate method to determine MeHg and Hg methylation/demethylation processes in environmental samples. RESULTS: Herein, an automatic ethylation-purge and trap-GC-ICP-MS system based on isotope dilution method for MeHg analysis was developed. The results showed that the limit of detection of the developed method was 0.01 ng L-1, the MeHg can be analyzed within 6 min with a relative standard deviation of 4.3 %. The accuracy of this proposed method was verified by the satisfying recoveries of certified reference materials (99.0 ± 0.35 % in ECM-CC580, sediment; 98.0 ± 0.67 % in DORM-4, Fish protein). In addition, comparable concentrations of MeHg in natural water were measured using both of the developed and classical distillation methods. Subsequently, the developed method was adapted for measuring concentrations of MeHg in the water, sediment, and fish muscle collected from the coastal and freshwater systems. Finally, the photic demethylation and biotic methylation/demethylation rate constants in natural surface water and sediment were determined using isotope dilution/tracing methods by automatic ethylation-purge and trap-GC-ICP-MS. SIGNIFICANCE AND NOVELTY: The developed automatic ethylation-purge and trap-GC-ICP-MS system is promising for accurate and convenient MeHg analysis and Hg biogeochemical cycling investigation in real environmental samples with isotope dilution and tracing methods.


Assuntos
Cromatografia Gasosa-Espectrometria de Massas , Mercúrio , Compostos de Metilmercúrio , Compostos de Metilmercúrio/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Metilação , Mercúrio/análise , Animais , Desmetilação , Poluentes Químicos da Água/análise , Monitoramento Ambiental/métodos
15.
Adv Mater ; : e2405233, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39091054

RESUMO

Light-induced ferroelectric polarization in 2D layered ferroelectric materials holds promise in photodetectors with multilevel current and reconfigurable capabilities. However, translating this potential into practical applications for high-density optoelectronic information storage remains challenging. In this work, an α-In2Se3/Te heterojunction design that demonstrates spatially resolved, multilevel, nonvolatile photoresponsivity is presented. Using photocurrent mapping, the spatially localized light-induced poling state (LIPS) is visualized in the junction region. This localized ferroelectric polarization induced by illumination enables the heterojunction to exhibit enhanced photoresponsivity. Unlike previous reports that observe multilevel polarization enhancement in electrical resistance, the device shows nonvolatile photoresponsivity enhancement under illumination. After polarization saturation, the photocurrent increases up to 1000 times, from 10-12 to 10-9 A under the irradiation of a 520 nm laser with a power of 1.69 nW, compared to the initial state in a self-driven mode. The photodetector exhibits high detectivity of 4.6×1010 Jones, with a rise time of 27 µs and a fall time of 28 µs. Furthermore, the device's localized poling characteristics and multilevel photoresponse enable spatially multiplexed optical information storage. These results advance the understanding of LIPS in 2D ferroelectric materials, paving the way for optoelectronic information storage technologies.

16.
Opt Lett ; 49(17): 4922-4925, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39207998

RESUMO

Mid-infrared hollow-core fiber (HCF) gas lasers based on a population inversion regime of gas molecules have made advanced development in recent years, but mostly with single-pass cavity-free structures. Here, we demonstrated a 3.1 µm high-power acetylene-filled HCF continuous wave (CW) laser and a self-Q-switched pulse laser with a linear-cavity structure. This configuration not only facilitates the transformation of amplified spontaneous emission into the laser output but also enhances the coherence of the light source and imparts distinct cavity mode characteristics. Harnessing a homemade high-power 1535 nm single-frequency fiber laser that served as the pump source, a CW laser output of 8.23 W at 3.1 µm was achieved, which is over three orders of magnitude higher than those in reported works so far. The corresponding slope efficiency of 31.8% and beam quality of Mx 2 = 1.18 and My 2 = 1.15 were characterized. When the gas pressure was up to 50 mbar, the laser generated a 3.1 µm self-Q-switched pulse with an output power of 1.98 W as well as a pulse width of 45 ns under the repetition rate of 4.59 MHz. To the best of our knowledge, this is the first time that an HCF gas laser achieves a self-Q-switched pulse. Future studies will aim to further optimize the experimental setup, potentially enabling the direct generation of picosecond pulses in the mid-infrared wavelength band.

17.
Toxics ; 12(8)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39195661

RESUMO

Glyphosate is the most widely used herbicide in the world. This study aimed to evaluate the relationships among urinary glyphosate, all-cause mortality and cardiovascular diseases (CVD)-related mortality in the general US population of adults, and to determine the role of alkaline phosphatase (ALP), an inflammation marker that is associated with glyphosate exposure, in these relationships. Subjects from the National Health and Nutrition Examination Survey (NHANES) 2013-2018 cycles were included. Survey-weighted Cox regression analysis was applied to estimate the relationship of glyphosate with overall and CVD mortalities. Restricted cubic spline (RCS) analysis was utilized to detect the linearity of associations. The intermediary role of ALP was explored by mediation analysis. Our results found consistent and positive associations of glyphosate with all-cause mortality (HR: 1.29, 95%CI: 1.05-1.59) and CVD mortality (HR: 1.32, 95%CI: 1.02-1.70). RCS curves further validated linear and positive dose-dependent relationships between glyphosate and mortality-related outcomes. Moreover, serum ALP was identified as a mediator in these associations and explained 12.1% and 14.0% of the total associations between glyphosate and all-cause death and CVD death risk, respectively. Our study indicated that glyphosate was associated with increased all-cause and CVD mortality in humans. Increased ALP may play an essential role in these associations.

18.
Viruses ; 16(8)2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39205202

RESUMO

Oncolytic viruses combined with immunotherapy offer significant potential in tumor therapy. In this study, we engineered a further attenuated pseudorabies virus (PRV) vaccine strain that incorporates a PD-L1 inhibitor and demonstrated its promise as an oncolytic virus in tumor therapy. We first showed that the naturally attenuated PRV vaccine strain Bartha can efficiently infect tumor cells from multiple species, including humans, mice, and dogs in vitro. We then evaluated the safety and anti-tumor efficacy of this vaccine strain and its different single-gene deletion mutants using the B16-F10 melanoma mouse model. The TK deletion strain emerged as the optimal vector, and we inserted a PD-L1 inhibitor (iPD-L1) into it using CRISPR/Cas9 technology. Compared with the control, the recombinant PRV (rPRV-iPD-L1) exhibited more dramatic anti-tumor effects in the B16-F10 melanoma mouse model. Our study suggests that PRV can be developed not only as an oncolytic virus but also a powerful vector for expressing foreign genes to modulate the tumor microenvironment.


Assuntos
Antígeno B7-H1 , Herpesvirus Suídeo 1 , Melanoma Experimental , Terapia Viral Oncolítica , Vírus Oncolíticos , Animais , Camundongos , Vírus Oncolíticos/genética , Herpesvirus Suídeo 1/genética , Herpesvirus Suídeo 1/fisiologia , Terapia Viral Oncolítica/métodos , Melanoma Experimental/terapia , Humanos , Antígeno B7-H1/antagonistas & inibidores , Antígeno B7-H1/genética , Linhagem Celular Tumoral , Camundongos Endogâmicos C57BL , Feminino , Cães , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Vetores Genéticos/genética , Imunoterapia/métodos , Microambiente Tumoral
19.
Opt Lett ; 49(13): 3636-3639, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950228

RESUMO

We report a 20-W-level acetylene-filled nested hollow-core anti-resonant fiber (nested HC-ARF) amplified spontaneous emission (ASE) source at 3.1 µm. A 1535 nm hundred-watt wavelength tunable single-frequency fiber laser with a high signal-to-noise ratio and narrow linewidth is built for pumping acetylene molecules. Simultaneously, a homemade 120 µm core diameter eight-tube nested HC-ARF is used as a gas chamber to obtain high pump laser coupling efficiency. The mid-infrared (mid-IR) ASE source output power of 21.8 W is achieved at 3.1 µm through the low-pressure acetylene gas-filled nested HC-ARF, and the slope efficiency is 25.1%. In addition, the ASE source features an excellent beam quality of Mx 2 = 1.16 and My 2 = 1.13. To the best of our knowledge, for the first time, it is a record output power for such mid-infrared ASE sources while maintaining excellent beam quality. This work provides a new way to achieve high-power mid-infrared emission.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 322: 124834, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-39032231

RESUMO

Iron ion (Fe3+) detection is crucial for human health since it plays a crucial role in many physiological activities. In this work, a novel Schiff-base functionalized cyanine derivative (CyPy) was synthesized, which was successfully assembled on the surface of upconversion nanoparticles (UCNPs) through an amphiphilic polymer encapsulation method. In the as-designed nanoprobe, CyPy, a recognizer of Fe3+, is served as energy donor and ß-NaYF4:Yb,Er upconversion nanoparticles are adopted as energy acceptor. As a result, a 93-fold enhancement of upconversion luminescence is achieved. The efficient energy transfer from CyPy to ß-NaYF4:Yb,Er endows the nanoprobe a high sensitivity for Fe3+ in water with a low detection limit of 0.21 µM. Moreover, the nanoprobe has been successfully applied for Fe3+ determination in human serum and tap water samples with recovery ranges of 95 %-105 % and 97 %-106 %, respectively. Moreover, their relative standard deviations are all below 3.72 %. This work provides a sensitive and efficient methodology for Fe3+ detection in clinical and environmental testing.


Assuntos
Ferro , Elementos da Série dos Lantanídeos , Limite de Detecção , Nanopartículas , Humanos , Ferro/análise , Ferro/química , Ferro/sangue , Nanopartículas/química , Elementos da Série dos Lantanídeos/química , Água Potável/análise , Corantes/química , Água/química
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