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1.
J Environ Sci (China) ; 149: 139-148, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181629

RESUMO

The dissolved organic matter (DOM) with high mobility and reactivity plays a crucial role in soil. In this study, the characteristics and phytotoxicity of DOM released from the hydrochars prepared from different feedstocks (cow manure, corn stalk and Myriophyllum aquaticum) under three hydrothermal carbonization (HTC) temperatures (180, 200 and 220°C) were evaluated. The results showed that the hydrochars had high dissolved organic carbon content (20.15 to 37.65 mg/g) and its content showed a gradual reduction as HTC temperature increased. Three fluorescent components including mixed substance of fulvic acid-like and humic acid-like substances (C1, 30.92%-58.32%), UVA humic acid-like substance (C2, 25.27%-29.94%) and protein-like substance (C3, 11.74%-41.92%) were identified in hydrochar DOM by excitation emission matrix spectra coupled with parallel factor analysis. High HTC temperature increased the relative proportion of aromatic substances (C1+C2) and humification degree of hydrochar DOM from cow manure, while it presented adverse effects on the hydrochar DOM from corn stalk and Myriophyllum. aquaticum. The principal component analysis suggested that feedstock type and HTC temperature posed significant effects on the characteristics of hydrochar DOM. Additionally, seed germination test of all hydrochar DOM demonstrated that the root length was reduced by 8.88%-26.43% in contrast with control, and the germination index values were 73.57%-91.12%. These findings provided new insights into the potential environmental effects for hydrochar application in soil.


Assuntos
Substâncias Húmicas , Substâncias Húmicas/análise , Solo/química , Temperatura , Poluentes do Solo/toxicidade , Poluentes do Solo/análise , Zea mays/efeitos dos fármacos , Esterco , Carvão Vegetal/química
2.
J Environ Sci (China) ; 149: 126-138, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181628

RESUMO

With the continuous control of anthropogenic emissions, China's air quality has improved significantly in recent years. Given this background, research on how the short-term exposure risks caused by air pollution in China have changed is insufficient. This study utilized hourly concentration data from ground observation stations and the official air quality guidelines of the Ministry of Ecology and Environment of China and the World Health Organization as standards to systematically investigate the spatiotemporal characteristics and short-term exposure risks of air pollution in China from 2015 to 2022. The results indicate that various atmospheric pollutants except for ozone showed a decreasing trend yearly. Nationwide, both single pollutant air pollution days (SAPDs) and multiple pollutant air pollution days (MAPDs) showed varying degrees of reduction within 15 and 25 days, respectively. SAPD was dominated mainly by excessive PM2.5 and PM10 pollutants, while MAPD was dominated mainly by excessive pollutant combinations, including PM2.5 + PM10, CO + PM2.5 + PM10, and SO2 + PM2.5 + PM10. As the concentration of atmospheric pollutants decreased, the total excess risk (ER) decreased yearly from 2015 to 2022, but there were significant regional differences. Now, the ER is less than 0.25% in southern China, in the range of 0.25%-0.5% in the North China Plain and some cities in the northeast, and higher than 1% in the northwest. Particulate matter is currently the primary pollutant posing short-term exposure risk in China, especially due to the impact of sandstorm weather. This study indicates that China's atmospheric cleaning action is significantly beneficial for reducing health risks.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Exposição Ambiental , Monitoramento Ambiental , Material Particulado , China , Poluição do Ar/estatística & dados numéricos , Poluentes Atmosféricos/análise , Material Particulado/análise , Humanos , Medição de Risco
3.
J Environ Sci (China) ; 149: 330-341, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181646

RESUMO

The emission of heavy-duty vehicles has raised great concerns worldwide. The complex working and loading conditions, which may differ a lot from PEMS tests, raised new challenges to the supervision and control of emissions, especially during real-world applications. On-board diagnostics (OBD) technology with data exchange enabled and strengthened the monitoring of emissions from a large number of heavy-duty diesel vehicles. This paper presents an analysis of the OBD data collected from more than 800 city and highway heavy-duty vehicles in China using remote OBD data terminals. Real-world NOx and CO2 emissions of China-6 heavy-duty vehicles have been examined. The results showed that city heavy-duty vehicles had higher NOx emission levels, which was mostly due to longer time of low SCR temperatures below 180°C. The application of novel methods based on 3B-MAW also found that heavy-duty diesel vehicles tended to have high NOx emissions at idle. Also, little difference had been found in work-based CO2 emissions, and this may be due to no major difference were found in occupancies of hot running.


Assuntos
Poluentes Atmosféricos , Dióxido de Carbono , Monitoramento Ambiental , Óxidos de Nitrogênio , Emissões de Veículos , Emissões de Veículos/análise , China , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Monitoramento Ambiental/métodos , Óxidos de Nitrogênio/análise , Cidades , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , Gasolina/análise
4.
J Environ Sci (China) ; 149: 386-393, 2025 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-39181651

RESUMO

To understand the smoke level and NOx emission characteristics of in-use construction machinery in Beijing, we selected 905 construction machines in Beijing from August 2022 to April 2023 to monitor the emission level of smoke and NOx. The exhaust smoke level and excessive emission situation of different machinery types were identified, and their NOx emission levels were monitored according to the free acceleration method. We investigated the correlation of NOx and smoke emission, and proposed suggestions for controlling pollution discharge from construction machinery in the future. The results show that the exhaust smoke level was 0-2.62 m-1, followed a log-normal distribution (µ = -1.73, δ = 1.09, R2 = 0.99), with a 5.64% exceedance rate. Differences were observed among machinery types, with low-power engine forklifts showing higher smoke levels. The NOx emission range was 71-1516 ppm, followed a normal distribution (µ = 565.54, δ = 309.51, R2 = 0.83). Differences among machinery types were relatively small. Engine rated net power had the most significant impact on NOx emissions. Thus, NOx emissions from construction machinery need further attention. Furthermore, we found a weak negative correlation (p < 0.05) between the emission level of smoke and NOx, that is the synergic emission reduction effect is poor, emphasizing the need for NOx emission limits. In the future, the oversight in Beijing should prioritize phasing out China Ⅰ and China Ⅱ machinery, and monitor emissions from high-power engine China Ⅲ machinery.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Fumaça , Pequim , Monitoramento Ambiental/métodos , Poluentes Atmosféricos/análise , Fumaça/análise , Emissões de Veículos/análise , Óxidos de Nitrogênio/análise , Indústria da Construção
5.
Biomaterials ; 313: 122771, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39190940

RESUMO

The notorious tumor microenvironment (TME) usually becomes more deteriorative during phototherapeutic progress that hampers the antitumor efficacy. To overcome this issue, we herein report the ameliorative and adaptive nanoparticles (TPASIC-PFH@PLGA NPs) that simultaneously reverse hypoxia TME and switch photoactivities from photothermal-dominated state to photodynamic-dominated state to maximize phototherapeutic effect. TPASIC-PFH@PLGA NPs are designed by incorporating oxygen-rich liquid perfluorohexane (PFH) into the intraparticle microenvironment to regulate the intramolecular motions of AIE photosensitizer TPASIC. TPASIC exhibits a unique aggregation-enhanced reactive oxygen species (ROS) generation feature. PFH incorporation affords TPASIC the initially dispersed state, thus promoting active intramolecular motions and photothermal conversion efficiency. While PFH volatilization leads to nanoparticle collapse and the formation of tight TPASIC aggregates with largely enhanced ROS generation efficiency. As a consequence, PFH incorporation not only currently promotes both photothermal and photodynamic efficacies of TPASIC and increases the intratumoral oxygen level, but also enables the smart photothermal-to-photodynamic switch to maximize the phototherapeutic performance. The integration of PFH and AIE photosensitizer eventually delivers more excellent antitumor effect over conventional phototherapeutic agents with fixed photothermal and photodynamic efficacies. This study proposes a new nanoengineering strategy to ameliorate TME and adapt the treatment modality to fit the changed TME for advanced antitumor applications.


Assuntos
Fluorocarbonos , Nanopartículas , Fotoquimioterapia , Fármacos Fotossensibilizantes , Espécies Reativas de Oxigênio , Microambiente Tumoral , Nanopartículas/química , Microambiente Tumoral/efeitos dos fármacos , Animais , Fotoquimioterapia/métodos , Espécies Reativas de Oxigênio/metabolismo , Fluorocarbonos/química , Fluorocarbonos/farmacologia , Linhagem Celular Tumoral , Fármacos Fotossensibilizantes/uso terapêutico , Fármacos Fotossensibilizantes/farmacologia , Fármacos Fotossensibilizantes/química , Humanos , Camundongos , Neoplasias/terapia , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Camundongos Endogâmicos BALB C , Terapia Fototérmica/métodos , Copolímero de Ácido Poliláctico e Ácido Poliglicólico/química , Fototerapia/métodos , Feminino
6.
J Environ Sci (China) ; 148: 221-229, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095159

RESUMO

Polychlorinated naphthalenes (PCNs) are detrimental to human health and the environment. With the commercial production of PCNs banned, unintentional releases have emerged as a significant environmental source. However, relevant information is still scarce. In this study, provincial emissions for eight PCNs homologues from 37 sources in the Chinese mainland during the period of 1960-2019 were estimated based on a source-specific and time-varying emission factor database. The results showed that the total PCNs emissions in 2019 reached 757.0 kg with Hebei ranked at the top among all the provinces and iron & steel industry as the biggest source. Low-chlorinated PCNs comprised 90% of emissions by mass, while highly chlorinated PCNs dominated in terms of toxicity, highlighting divergent priorities for mitigating emissions and safeguarding human health. The emissions showed an overall upward trend from 1960 to 2019 driven by emission increase from iron & steel industry in terms of source, and from North China and East China in terms of geographic area. Per-capita emissions followed an inverted U-shaped environmental Kuznets curve while emission intensities decreased with increasing per-capita Gross Domestic Product (GDP) following a nearly linear pattern when log-transformed.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Naftalenos , China , Naftalenos/análise , Poluentes Atmosféricos/análise , Poluição do Ar/estatística & dados numéricos
7.
J Environ Sci (China) ; 148: 665-682, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095198

RESUMO

Emission characteristics of biogenic volatile organic compounds (BVOCs) from dominant tree species in the subtropical pristine forests of China are extremely limited. Here we conducted in situ field measurements of BVOCs emissions from representative mature evergreen trees by using dynamic branch enclosures at four altitude gradients (600-1690 m a.s.l.) in the Nanling Mountains of southern China. Composition characteristics as well as seasonal and altitudinal variations were analyzed. Standardized emission rates and canopy-scale emission factors were then calculated. Results showed that BVOCs emission intensities in the wet season were generally higher than those in the dry season. Monoterpenes were the dominant BVOCs emitted from most broad-leaved trees, accounting for over 70% of the total. Schima superba, Yushania basihirsuta and Altingia chinensis had relatively high emission intensities and secondary pollutant formation potentials. The localized emission factors of isoprene were comparable to the defaults in the Model of Emissions of Gases and Aerosols from Nature (MEGAN), while emission factors of monoterpenes and sesquiterpenes were 2 to 58 times of those in the model. Our results can be used to update the current BVOCs emission inventory in MEGAN, thereby reducing the uncertainties of BVOCs emission estimations in forested regions of southern China.


Assuntos
Poluentes Atmosféricos , Monitoramento Ambiental , Florestas , Compostos Orgânicos Voláteis , Compostos Orgânicos Voláteis/análise , China , Poluentes Atmosféricos/análise , Árvores , Estações do Ano
8.
J Environ Sci (China) ; 148: 702-713, 2025 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-39095202

RESUMO

Chinese diesel trucks are the main contributors to NOx and particulate matter (PM) vehicle emissions. An increase in diesel trucks could aggravate air pollution and damage human health. The Chinese government has recently implemented a series of emission control technologies and measures for air quality improvement. This paper summarizes recent control technologies and measures for diesel truck emissions in China and introduces the comprehensive application of control technologies and measures in Beijing-Tianjin-Hebei and surrounding regions. Remote online monitoring technology has been adopted according to the China VI standard for heavy-duty diesel trucks, and control measures such as transportation structure adjustment and heavy pollution enterprise classification control continue to support the battle action plan for pollution control. Perspectives and suggestions are provided for promoting pollution control and supervision of diesel truck emissions: adhere to the concept of overall management and control, vigorously promote the application of systematic and technological means in emission monitoring, continuously facilitate cargo transportation structure adjustment and promote new energy freight vehicles. This paper aims to accelerate the implementation of control technologies and measures throughout China. China is endeavouring to control diesel truck exhaust pollution. China is willing to cooperate with the world to protect the global ecological environment.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Material Particulado , Emissões de Veículos , Emissões de Veículos/análise , China , Poluentes Atmosféricos/análise , Poluição do Ar/prevenção & controle , Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Material Particulado/análise , Veículos Automotores
9.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124952, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39137708

RESUMO

Novel styryl colorants based on anchoring methoxy with anthracene as a donor linked with various active methylene acceptor groups to derive a conjugated π-system along with push-pull geometry were synthesized and well characterized. Photophysical properties were studied in different polarity solvents. The impact of solvent polarizability is delivered in redshifts in absorption and emission spectra, in addition to enhancing the quantum yield. The benzoxazole and benzimidazole moieties in 4c and 4d demonstrated heat stability of more than 300 °C. Fluorescent intensity is directly proportional to the viscosity and 4a demonstrates a notable viscosity sensor through 1.36 fold increase in intensity. In comparison to other styryl dyes, 4c and 4d were shown to have higher values in DMSO for polarizability (53.3496 × 10-24 esu and 53.7459 × 10-24 esu) and first-order hyperpolarizability (86.3467 × 10-30 esu and 89.1941 × 10-30 esu) as well as second-order hyperpolarizability (1768.9121 × 10-36 esu and 1740.6940 × 10-36 esu) due to presence of heterocyclic character. NLO properties of all the styryl dyes 4a-4e are within the fundamental boundary limits. The 4d (benzoxazole) dye exhibited a small HOMO-LUMO energy gap of 2.8825 eV, whereas the 4b and 4e dyes had a larger band gap due to the presence of a carbonyl group.

10.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124963, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39151400

RESUMO

Sm3+ions doped Phospho-Borate glasses were synthesized and their physical and spectroscopic parameters were studied to evaluate its potential reddish-orange emission for photonic applications. Structural investigation made through XRD analysis confirms the amorphous nature. The evaluated bonding parameters from the absorption spectral analysis confirm the ionic bonding of the Sm-O network in the prepared glasses. Four emission bands were observed from the luminescence spectra, and the HT 4G5/2 → 6H7/2 is observed at 601 nm. The oscillator strength values elucidate the intensity of the absorption bands, and the PBKZnF:Sm sample exhibits a higher oscillator strength value. The Judd-Ofelt intensity parameters were observed to trail the trend Ω4 > Ω6. > Ω2 for the majority of the samples. The CIE 1931 color chromaticity investigation confirms that the present glass samples are suitable for reddish-orange media. Barium and strontium-incorporated glasses exhibit outstanding lasing potential, which was confirmed through the efficiency of the quantum yield and some of the radiative parameters like effective bandwidth, transition probability and stimulated emission cross-section. Radiative parameters have been calculated from the luminescence spectra. Amid all transitions, 4G5/2 →6H7/2 transition has higher transition probability and higher stimulated emission cross-section values for all the prepared glass samples. Barium-incorporated glass exhibits a higher emission cross-section of 30.55 × 10-22 cm2 and a transition probability of 30.89 s-1 compared to all other glasses. The non-exponential decay profiles of the fabricated samples were plotted by examining the excitation wavelength at 402 nm and emission wavelength at 600 nm. Of all the prepared glasses, the quantum efficiency is found to be higher for the glass sample PBKSrF:Sm (65 %).

11.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 124955, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39173323

RESUMO

Designing persistent dual-band afterglow materials with thermally activated delayed fluorescence (TADF) and room temperature phosphorescence (RTP) contributed to solving the problems of homogenization and singularity in long afterglow materials. Here, six aryl acetonitrile (CBM) and aryl dicyanoaniline (AMBT) derivatives, used as host and guest materials respectively, were successfully designed and synthesized based on the isomerization effect. Among of them, 0.1 % m-CBM/p-AMBT showed the longest dual-band TADF (540 ms) and RTP lifetimes (721 ms), as well as persistent afterglow over 8 s, whose fluorescence (ΦFL), TADF (ΦT) and RTP (ΦP) quantum yields were 0.11, 0.06 and 0.22 in sequence. More interestingly, some doping systems constructed by CBM and AMBT series compounds showed persistent triple-band emissions composed of TADF, unimolecular and aggregated AMBT series compounds. What's more, ΦFL, ΦT and ΦP of 1 % o-AMBT@PMMA film were up to 0.17, 0.17, 0.23 in turn, with TADF, RTP and afterglow lifetimes of 606 ms, 727 ms, and 10 s respectively. TADF and RTP emission of CBM/AMBT series doping systems was attributed to host sensitized guest emission. Besides, the comparison displayed AMBT series compounds had bigger intensity ratios between TADF and RTP emission in PMMA films compared to in CBM series compounds. Finally, a series of data encryption were successfully constructed based on different afterglow lifetimes of the doping systems, and a dynamic anti-counterfeiting pattern was prepared by using different temperature responses of TADF and RTP emissions.

12.
Spectrochim Acta A Mol Biomol Spectrosc ; 324: 125011, 2025 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-39213831

RESUMO

Thiols function as antioxidants in food, prolonging shelf life and enhancing flavor. Moreover, thiols are vital biomolecules involved in enzyme activity, cellular signal transduction, and protein folding among critical biological processes. In this paper, the fluorescent probe PYL-NBD was designed and synthesized, which utilized the fluorescent molecule pyrazoline, the lysosome-targeted morpholine moiety, and the sensing moiety NBD. Probe PYL-NBD was tailored for the recognition of biothiols through single-wavelength excitation, yielding distinct fluorescence emission signals: blue for Cys, Hcy, and GSH; green for Cys, Hcy. Probe PYL-NBD exhibited rapid reaction kinetics (<10 min), distinct fluorescence response signals, and low detection limits (15.7 nM for Cys, 14.4 nM for Hcy, and 12.6 nM for GSH). Probe PYL-NBD enabled quantitative determination of Cys content in food samples and L-cysteine capsules. Furthermore, probe PYL-NBD had been successfully applied for confocal imaging with dual-channel detection of biothiols in various biological specimens, including HeLa cells, zebrafish, tumor sections, and Arabidopsis thaliana.


Assuntos
Cisteína , Corantes Fluorescentes , Análise de Alimentos , Glutationa , Lisossomos , Espectrometria de Fluorescência , Peixe-Zebra , Humanos , Corantes Fluorescentes/química , Corantes Fluorescentes/síntese química , Lisossomos/química , Lisossomos/metabolismo , Células HeLa , Cisteína/análise , Animais , Análise de Alimentos/métodos , Glutationa/análise , Espectrometria de Fluorescência/métodos , Homocisteína/análise , Arabidopsis/química , Limite de Detecção , Microscopia Confocal
13.
J Colloid Interface Sci ; 677(Pt B): 504-512, 2025 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-39154443

RESUMO

The commonly used artificial light sources, such as fluorescent lamps and white light-emitting diodes, often have a high ratio of blue light emission, which poses potential blue light hazards, especially one of the main culprits leading to eye diseases. Therefore, developing novel white lighting sources with low blue-hazard is highly appreciated. In this work, an air-stable and color-tunable triplet-triplet annihilation upconversion (TTA-UC) mechanism was proposed to realize the low blue-hazard white-light emission. The proposed design was composed of three primary RGB colors from the annihilator (9,10-diphenylanthracene, DPA), the laser excitation source, and the photosensitizer (palladium (II) octaetylporphyrin, PdOEP), respectively. The introduction of oil-in-water (o/w) microemulsion can effectively block the potential oxygen-induced triplet-quenching and benefit high UC efficiency. Moreover, either raising ambient temperatures or adding isobutanol can activate the UC process to yield white-light emission. Notably, the white-light emission with a Commission Internationale de l'Eclairage (CIE) coordinate of (0.33, 0.33) as well as a low ratio of blue emission (14.2 %) was achieved at an ambient temperature of 42 °C. Therefore, the proposed air-stable TTA-UC mechanism can significantly lower the blue-hazard and provide a novel solution for applications in lighting and display.

14.
J Environ Sci (China) ; 150: 604-621, 2025 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-39306433

RESUMO

Recently, the transportation sector in China has gradually become the main source of urban air pollution and primary driver of carbon emissions growth. Considering air pollutants and greenhouse gases come from the same emission sources, it is necessary to establish an updated high-resolution emission inventory for the transportation sector in Central China, the most polluted region in China. The inventory includes on-road mobile, non-road mobile, oil storage and transportation, and covers 9 types of air pollutants and 3 types of greenhouse gases. Based on the Long-range Energy Alternatives Planning System (LEAP) model, the emissions of pollutants were predicted for the period from 2020 to 2035 in different scenarios. Results showed that in 2020, emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, NH3, BC, OC, CO2, CH4, and N2O in Henan Province were 27.5, 503.2, 878.6, 20.1, 17.4, 222.1, 21.5, 9.4, 2.9, 92,077.9, 6.0, and 10.4 kilotons, respectively. Energy demand and pollutant emissions in Henan Province are simulated under four scenarios (Baseline Scenario (BS), Pollution Abatement Scenario (PA), Green Transportation Scenario (GT), and Reinforcing Low Carbon Scenario (RLC)). The collaborative emission reduction effect is most significant in the RLC scenario, followed by the GT scenario. By 2035, under the RLC scenario, energy consumption and emissions of SO2, NOx, CO, PM10, PM2.5, VOCs, NH3, CO2, CH4, and N2O are projected to decrease by 72.0%, 30.0%, 55.6%, 56.0%, 38.6%, 39.7%, 51.5%, 66.1%, 65.5%, 55.4%, and 52.8%, respectively. This study provides fundamental data support for subsequent numerical simulations.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Monitoramento Ambiental , Gases de Efeito Estufa , China , Poluentes Atmosféricos/análise , Gases de Efeito Estufa/análise , Monitoramento Ambiental/métodos , Poluição do Ar/estatística & dados numéricos , Poluição do Ar/análise , Meios de Transporte , Emissões de Veículos/análise
15.
Eur Radiol ; 2024 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-39387873

RESUMO

Neuroendocrine neoplasms (NEN) originate from the secretory cells of the neuroendocrine system, with the majority arising in the gastrointestinal tract and pancreas. Given the heterogeneity in the biological behavior and morphological differentiation of these tumors, advanced imaging techniques are crucial for supporting the suspected diagnosis, accurate staging, and monitoring therapy. As most well-differentiated NEN demonstrate overexpression of somatostatin receptors (SSR) on the cell surface, SSR-directed PET/CT is considered the reference standard for imaging of this particular entity. SSR-PET/CT should be the imaging method of choice in every NEN G1 or G2 and considered for re-staging after both potentially curative and non-curative surgeries. The extent of SSR expression is also crucial for determining a patient's eligibility for peptide receptor radionuclide therapy (PRRT). PRRT utilizes [177Lu]Lu-DOTA-TATE to target the SSR receptor and can significantly prolong progression-free survival in patients with advanced, progressive neuroendocrine tumor of the gastroenteropancreatic system (GEP-NET). PET/CT is a central component of the multidisciplinary management of NEN. Variable follow-up intervals are recommended, considering that tumors with higher proliferation rates or advanced metastatic disease require more frequent assessments. The combination with other imaging modalities, like MRI, complements SSR-PET/CT, further enhancing overall diagnostic accuracy. KEY POINTS: Somatostatin receptor-PET/CT (SSR-PET/CT) is the guideline-recommended reference standard for imaging well-differentiated neuroendocrine tumors (NET). SSR-PET/CT should be the diagnostic imaging of choice for staging and post-therapy re-staging of grade 1 or 2 NET (G1 or G2). Variable follow-up intervals are recommended for NET G1 and G2. Tumors with higher proliferation rates or advanced metastatic disease necessitate more frequent assessments.

16.
EJNMMI Res ; 14(1): 88, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356393

RESUMO

BACKGROUND: Skeletal muscles are vital for daily function, yet assessing their injuries remain challenging. We aimed to elucidate the effectiveness of 68Ga-FAPI-04 in evaluating skeletal muscle remodeling. RESULTS: C2C12 cells were subjected to graded H2O2 stimulation in vitro, revealing an initial rise and subsequent decline in fibroblast activation protein (FAP) expression as H2O2 concentration increased. In vivo, a murine triceps surae injury model was created using various solutions to simulate normal repair, mild repair failure, and severe repair failure. Assessments were conducted on days 1, 3, 7, and 14 using PET, MRI, and ultrasound. With 68Ga-FAPI-04, the normal and mild repair failure groups showed significantly higher SUVmax and T/B ratios on day 1 compared to the severe repair failure group. These values gradually decreased in the normal repair group, becoming negligible after day 7. MRI results for the normal repair group showed low to moderate signal intensity by day 7. A clinical study retrospectively evaluated post-hip arthroplasty patient images at intervals of 1 month, 2-3 months, 5-6 months, and over 7 months. In these patients, 18F-FDG SUVmax and volume remained relatively stable over time, while 68Ga-FAPI-04 SUVmax initially increased, then decreased, with a consistent reduction in volume. CONCLUSION: In skeletal muscle injuries, FAP demonstrates a distinctive mechanism of action, and 68Ga-FAPI-04, in comparison to other tests, more precisely captures alterations in lesion site uptake intensity and volume. TRIAL REGISTRATION: Trial registration: ChiCTR2000041204. Registered 22 December 2020, https://www.chictr.org.cn/showproj.html?proj=66211.

17.
EJNMMI Res ; 14(1): 89, 2024 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-39356412

RESUMO

BACKGROUND: Severe large vessel disease may lead to cerebral hemodynamic failure that critically impairs cerebral blood flow (CBF) regulation elevating the risk of ischemic events. Assessment of the condition is often based on changes in CBF during vasodilatation; however, pharmacologically induced vasodilation does not reflect the physiological condition during an ischemic event caused by hemodynamic failure. We compared a [15O]H2O PET brain scan during vasodilation to a [99mTc]HMPAO SPECT brain scan during an ongoing transient ischemic attack (TIA). CASE PRESENTATION: A single patient presenting with limb-shaking TIA underwent CT, Digital Subtraction Angiography, and two different modalities of cerebral perfusion scans: [15O]H2O PET and [99mTc]HMPAO SPECT. Acetazolamide was used in the PET scan to induce vasodilatation, and during the SPECT scan physiological stress, standing up rapidly, was used to induce limb-shaking TIA. CT-angiography and Digital Subtraction Angiography revealed an occlusion in the distal part of the right A2 segment of the anterior cerebral artery, with a corresponding infarction in the watershed area. Collaterals supplied the main vascular territory of the anterior cerebral artery. During rest, neither perfusion modalities demonstrated reduced perfusion outside of the ischemic core. However, we found a pronounced difference between the PET utilizing acetazolamide and the SPECT during the TIA. The PET scan demonstrated relative hypoperfusion in vascular territory supplied by collaterals, while the area around the ischemic core was not affected. Contrary, the SPECT had only minor relative hypoperfusion in the collateral-supplied area, whereas the watershed area proximal to the infarct core had pronounced relative hypoperfusion. CONCLUSIONS: The observed discrepancy in compromised areas during physiological provocation compared to pharmacological induced vasodilation questions the use of an unphysiological stressor for assessment of cerebrovascular hemodynamics. A physiological provocation test may achieve more clinically relevant evaluation.

18.
Biomaterials ; 314: 122847, 2024 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-39357148

RESUMO

Organic photosensitizers (PSs) play important roles in phototheranostics, and contribute to the fast development of precision medicine. However, water-soluble and highly emissive organic PSs, especially those emitting in the short-wave infrared region (SWIR), are still challenging. Also, it's difficult to prepare self-reporting PSs for visualizing the treatment via stimulated emission depletion (STED) nanoscopy. Thus, in this work, a water-soluble molecule of DTPAP-TBZ-I with aggregation-induced emission features is designed for the self-reporting photodynamic therapy (PDT) in an ultra-high resolution. In contrast to single molecule, its complex (DTPAP-TBZ-I@BSA) shows much enhanced fluorescence properties and reactive oxygen species (ROS) generation in SWIR window. Their photoluminescence quantum yield is determined to be ∼20.6 % and the enhancement of ROS generation is ∼18-fold. During the PDT, immigration of the complex from cytoplasm to nucleus is also observed via STED nanoscopy with a resolution of 66.11 nm, which allows self-report in the PDT treatment. DTPAP-TBZ-I@BSA is finally utilized for the imaging-guided PDT in vivo with a tumor inhibition rate of 84 %. This is the first work in albumin-enhanced water-soluble organic PSs in SWIR window for self-reporting phototheranostics at ultra-high resolutions, providing an ideal solution for the next generation of photosensitizers for precise medicine.

19.
J Environ Manage ; 370: 122671, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39357443

RESUMO

Tailwater from wastewater treatment plants (WWTP) usually reduces the nitrogen (N) removal efficiency while simultaneously elevates nitrous oxide (N2O) emissions due to the low carbon-nitrogen (C/N) ratio. Conflicts between N removal and N2O emissions require mitigation by selecting appropriate aquatic plants for tailwater treatment. In this study, a simulated tailwater mesocosm was established using three aquatic plants including Eichhornia crassipes, Myriophyllum aquaticum and Pistia stratiotes. Results of the 15N isotope mass balance analysis revealed the considerable contributions from plant uptake and benthic retention to overall N removal. It was demonstrated that the N assimilation efficiency of aquatic plants depended more on the root-shoot ratio rather than on growth rate. Furthermore, aquatic plants indirectly influence microbial N removal and N2O emissions by altering the water quality parameters. Additionally, aquatic plants could regulate the N transformation through affecting the structure of bacterial community, including microbial abundance, diversity and association networks. Overall, the study underlined the enormous capacities of E. crassipes and P. stratiotes for N uptake and N2O mitigation in tailwater treatment. Utilizing these two aquatic plants for phytoremediation may help mitigate the conflict between tailwater purification and N2O production.

20.
J Environ Manage ; 370: 122700, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39357445

RESUMO

Forest transformation can markedly impact soil greenhouse gas emissions and soil environmental factors. Due to increasing labor costs and declining bamboo prices, the abandonment of Moso bamboo forests is sharply escalating in recent years, which weakens the carbon sequestration capacity and decreases the ecological function of forests. To improve the ecological quality of abandoned Moso bamboo forests, transformations of abandoned bamboo forests have occurred. However, the impact of such transformations on N2O emissions remains elusive. To bridge the knowledge gap, we conducted a 23-month field experiment to compare the effects of various forest management practices on soil N2O emissions and soil environmental factors in abandoned Moso bamboo forests in subtropical China. These practices included uncut abandonment as a control, intensive management, three intensities (light, moderate, and heavy) of strip clear-cutting with replanting local tree species, and clear-cutting with replanting transformation. During the experimental period, the mean soil N2O flux in abandoned Moso bamboo forests was 13.2 ± 0.1 µg m-2 h-1, representing a 44% reduction compared to intensive management forests. In comparison to the uncut control, light, moderate, and heavy strip clear-cutting and clear-cutting transformations increased soil N2O emission rates by 20%, 43%, 64%, and 94%, respectively. Soil temperature (69-71%), labile C (2-6%) and N (3-8%) were the main factors that explain N2O emissions following the transformation of abandoned Moso bamboo forests. Additionally, replanting could decrease soil N2O emissions by increasing the contribution of soil moisture. Overall, the light strip clear-cutting transformation is suggested to convert abandoned Moso bamboo forests to mitigate N2O emissions.

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