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1.
Proc Natl Acad Sci U S A ; 121(15): e2320505121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38568977

RESUMO

The presynaptic SNARE-complex regulator complexin (Cplx) enhances the fusogenicity of primed synaptic vesicles (SVs). Consequently, Cplx deletion impairs action potential-evoked transmitter release. Conversely, though, Cplx loss enhances spontaneous and delayed asynchronous release at certain synapse types. Using electrophysiology and kinetic modeling, we show that such seemingly contradictory transmitter release phenotypes seen upon Cplx deletion can be explained by an additional of Cplx in the control of SV priming, where its ablation facilitates the generation of a "faulty" SV fusion apparatus. Supporting this notion, a sequential two-step priming scheme, featuring reduced vesicle fusogenicity and increased transition rates into the faulty primed state, reproduces all aberrations of transmitter release modes and short-term synaptic plasticity seen upon Cplx loss. Accordingly, we propose a dual presynaptic function for the SNARE-complex interactor Cplx, one as a "checkpoint" protein that guarantees the proper assembly of the fusion machinery during vesicle priming, and one in boosting vesicle fusogenicity.


Assuntos
Sinapses , Vesículas Sinápticas , Sinapses/metabolismo , Vesículas Sinápticas/metabolismo , Potenciais de Ação , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteínas SNARE/genética , Proteínas SNARE/metabolismo , Transmissão Sináptica/fisiologia
2.
Environ Res ; 252(Pt 2): 118919, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631468

RESUMO

The escalation of global water pollution due to emerging pollutants has gained significant attention. To address this issue, catalytic peroxymonosulfate (PMS) activation technology has emerged as a promising treatment approach for effectively decontaminating a wide range of pollutants. Recently, modified biochar has become an increasingly attractive as PMS activator. Metal-heteroatom-co-doped biochar (MH-BC) has emerged as a promising catalyst that can provide enhanced performance over heteroatom-doped and metal-doped biochar due to the synergism between metal and heteroatom in promoting PMS activation. Therefore, this review aims to discuss the fabrication pathways (i.e., internal vs external doping and pre-vs post-modification) and key parameters (i.e., source of precursors, synthesis methods, and synthesis conditions) affecting the performance of MH-BC as PMS activator. Subsequently, an overview of all the possible PMS activation pathways by MH-BC is provided. Subsequently, Also, the detection, identification, and quantification of several reactive species (such as, •OH, SO4•-, O2•-, 1O2, and high valent oxo species) generated in the catalytic PMS system by MH-BC are also evaluated. Lastly, the underlying challenges associated with poor stability, the lack of understanding regarding the interaction between metal and heteroatom during PMS activation and quantification of radicals in multi-ROS system are also deliberated.

3.
EJNMMI Radiopharm Chem ; 9(1): 27, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563872

RESUMO

BACKGROUND: Tau pathology plays a crucial role in neurodegeneration diseases including Alzheimer's disease (AD) and non-AD diseases such as progressive supranuclear palsy. Tau positron emission tomography (PET) is an in-vivo and non-invasive medical imaging technique for detecting and visualizing tau deposition within a human brain. In this work, we aim to investigate the biodistribution of the dosimetry in the whole body and various organs for the [18F]Florzolotau tau-PET tracer. A total of 12 healthy controls (HCs) were enrolled at Chang Gung Memorial Hospital. All subjects were injected with approximately 379.03 ± 7.03 MBq of [18F]Florzolotau intravenously, and a whole-body PET/CT scan was performed for each subject. For image processing, the VOI for each organ was delineated manually by using the PMOD 3.7 software. Then, the time-activity curve of each organ was acquired by optimally fitting an exponential uptake and clearance model using the least squares method implemented in OLINDA/EXM 2.1 software. The absorbed dose for each target organ and the effective dose were finally calculated. RESULTS: From the biodistribution results, the elimination of [18F]Florzolotau is observed mainly from the liver to the intestine and partially through the kidneys. The highest organ-absorbed dose occurred in the right colon wall (255.83 µSv/MBq), and then in the small intestine (218.67 µSv/MBq), gallbladder wall (151.42 µSv/MBq), left colon wall (93.31 µSv/MBq), and liver (84.15 µSv/MBq). Based on the ICRP103, the final computed effective dose was 34.9 µSv/MBq with CV of 10.07%. CONCLUSIONS: The biodistribution study of [18F]Florzolotau demonstrated that the excretion of [18F]Florzolotau are mainly through the hepatobiliary and gastrointestinal pathways. Therefore, a routine injection of 370 MBq or 185 MBq of [18F]Florzolotau leads to an estimated effective dose of 12.92 or 6.46 mSv, and as a result, the radiation exposure to the whole-body and each organ remains within acceptable limits and adheres to established constraints. TRIAL REGISTRATION: Retrospectively Registered at Clinicaltrials.gov (NCT03625128) on 12 July, 2018, https://clinicaltrials.gov/study/NCT03625128 .

4.
Environ Sci Pollut Res Int ; 31(18): 26773-26789, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38456975

RESUMO

In this study, CoCr layered double hydroxide material (CoCr-LDH) was prepared and used as an effective catalyst for peroxymonosulfate (PMS) activation to degrade organics in water. The prepared CoCr-LDH material had a crystalline structure and relatively porous structure, as determined by various surface analyses. In Rhodamine B (RhB) removal, the most outstanding PMS activation ability belongs to the material with a Co:Cr molar ratio of 2:1. The removal of RhB follows pseudo-first-order kinetics (R2 > 0.99) with an activation energy of 38.23 kJ/mol and efficiency of 98% after 7 min of treatment, and the total organic carbon of the solution reduced 47.2% after 10 min. The activation and oxidation mechanisms were proposed and the RhB degradation pathways were suggested with the key contribution of O2•- and 1O2. Notably, CoCr-LDH can activate PMS over a wide pH range of 4 - 9, and apply to a wide range of organic pollutants and aqueous environments. The material has high stability and good recovery, which can be reused for 5 cycles with a stable efficiency of above 88%, suggesting a high potential for practical recalcitrant water treatment via PMS activation by heterogeneous catalysts.


Assuntos
Peróxidos , Poluentes Químicos da Água , Purificação da Água , Poluentes Químicos da Água/química , Peróxidos/química , Purificação da Água/métodos , Rodaminas/química , Cinética , Oxirredução , Catálise
5.
Clin Nucl Med ; 49(5): 387-396, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38465965

RESUMO

BACKGROUND: Progressive supranuclear palsy (PSP) is a tauopathy that involves subcortical regions but also extends to cortical areas. The clinical impact of different tau protein sites and their influence on glymphatic dysfunction have not been investigated. PATIENTS AND METHODS: Participants (n = 55; 65.6 ± 7.1 years; 29 women) with PSP (n = 32) and age-matched normal controls (NCs; n = 23) underwent 18 F-Florzolotau tau PET, MRI, PSP Rating Scale (PSPRS), and Mini-Mental State Examination. Cerebellar gray matter (GM) and parametric estimation of reference signal intensity were used as references for tau burden measured by SUV ratios. Glymphatic activity was measured by diffusion tensor image analysis along the perivascular space (DTI-ALPS). RESULTS: Parametric estimation of reference signal intensity is a better reference than cerebellar GM to distinguish tau burden between PSP and NCs. PSP patients showed higher cortical and subcortical tau SUV ratios than NCs ( P < 0.001 and <0.001). Cortical and subcortical tau deposition correlated with PSPRS, UPDRS, and Mini-Mental State Examination scores (all P 's < 0.05). Cortical tau deposition was further associated with the DTI-ALPS index and frontal-temporal-parietal GM atrophy. The DTI-ALPS indexes showed a significantly negative correlation with the PSPRS total scores ( P < 0.01). Finally, parietal and occipital lobe tau depositions showed mediating effects between the DTI-ALPS index and PSPRS score. CONCLUSIONS: Cortical tau deposition is associated with glymphatic dysfunction and plays a role in mediating glymphatic dysfunction and clinical severity. Our results provide a possible explanation for the worsening of clinical severity in patients with PSP.


Assuntos
Paralisia Supranuclear Progressiva , Proteínas tau , Humanos , Feminino , Proteínas tau/metabolismo , Paralisia Supranuclear Progressiva/metabolismo , Imageamento por Ressonância Magnética , Processamento de Imagem Assistida por Computador
6.
Nanoscale ; 16(13): 6708-6719, 2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38488127

RESUMO

Hypertrophic scar (HS) is characterized by an abnormal fibroblast-myofibroblast transformation; non-apoptosis of fibroblasts; and redundant expression of TGF-ß1, VEGF, α-SMA, and collagen I/III. An HS affects patients' physical and psychological quality of life, leading to joint dysfunction and skin cancer. However, there is currently no satisfactory drug to treat this disorder. In this study, we constructed methylprednisolone sodium succinate (MPSS) encapsulated ZIF-90 (MPSS@ZIF-90) for the effective treatment of an HS. The encapsulation of MPSS in ZIF-90 can achieve the controllable drug release of MPSS and prolong its effective treatment time. MPSS@ZIF-90 enhanced the apoptosis of human hypertrophic scar fibroblasts and downregulated the overexpression of TGF-ß1, VEGF, α-SMA, and collagen I/III both in vitro and in vivo. The instant injection of MPSS@ZIF-90 effectively intervened with the formation of the HS after 28 days. On the contrary, MPSS@ZIF-90 greatly reduced the HS with two injections and 14 days of treatment after the HS was formed. This work provides evidence of effective intervention in the formation of an HS and the therapeutic effectiveness of MPSS@ZIF-90 with short treatment periods in vivo. It suggests that MPSS@ZIF-90 can be used as a biomedical option in the treatment of skin wounds and may reveal the potential molecular basis for promising future antifibrotic agents against scarring.


Assuntos
Cicatriz Hipertrófica , Estruturas Metalorgânicas , Nanopartículas , Humanos , Cicatriz Hipertrófica/tratamento farmacológico , Fator de Crescimento Transformador beta1/metabolismo , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/uso terapêutico , Hemissuccinato de Metilprednisolona/metabolismo , Hemissuccinato de Metilprednisolona/farmacologia , Hemissuccinato de Metilprednisolona/uso terapêutico , Qualidade de Vida , Fator A de Crescimento do Endotélio Vascular/metabolismo , Fibroblastos/metabolismo , Colágeno Tipo I
7.
Chem Sci ; 15(10): 3721-3729, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38455009

RESUMO

Overcoming thermal quenching is generally essential for the practical application of luminescent materials. It has been recently found that frameworks with negative thermal expansion (NTE) could be a promising candidate to engineer unconventional luminescence thermal enhancement. However, the mechanism through which luminescence thermal enhancement can be well tuned remains an open issue. In this work, enabled by altering ligands in a series of UiO-66 derived Eu-based metal-organic frameworks, it was revealed that the changes in the thermal expansion are closely related to luminescence thermal enhancement. The NTE of the aromatic ring part favors luminescence thermal enhancement, while contraction of the carboxylic acid part plays the opposite role. Modulation of functional groups in ligands can change the thermal vibration of aromatic rings and then achieve luminescence thermal enhancement in a wide temperature window. Our findings pave the way to manipulate the NTE and luminescence thermal enhancement based on ligand engineering.

8.
Nat Commun ; 15(1): 2252, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38480744

RESUMO

Zero thermal expansion (ZTE) alloys with high mechanical response are crucial for their practical usage. Yet, unifying the ZTE behavior and mechanical response in one material is a grand obstacle, especially in multicomponent ZTE alloys. Herein, we report a near isotropic zero thermal expansion (αl = 1.10 × 10-6 K-1, 260-310 K) in the natural heterogeneous LaFe54Co3.5Si3.35 alloy, which exhibits a super-high toughness of 277.8 ± 14.7 J cm-3. Chemical partition, in the dual-phase structure, assumes the role of not only modulating thermal expansion through magnetic interaction but also enhancing mechanical properties via interface bonding. The comprehensive analysis reveals that the hierarchically synergistic enhancement among lattice, phase interface, and heterogeneous structure is significant for strong toughness. Our findings pave the way to tailor thermal expansion and obtain prominent mechanical properties in multicomponent alloys, which is essential to ultra-stable functional materials.

9.
J Orthop Surg Res ; 19(1): 183, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491545

RESUMO

Osteonecrosis of the femoral head (ONFH) is a elaborate hip disease characterized by collapse of femoral head and osteoarthritis. RNA N6-methyladenosine (m6A) plays a crucial role in a lot of biological processes within eukaryotic cells. However, the role of m6A in the regulation of ONFH remains unclear. In this study, we identified the m6A regulators in ONFH and performed subtype classification. We identified 7 significantly differentially expressed m6A regulators through the analysis of differences between ONFH and normal samples in the Gene Expression Omnibus (GEO) database. A random forest algorithm was employed to monitor these regulators to assess the risk of developing ONFH. We constructed a nomogram based on these 7 regulators. The decision curve analysis suggested that patients can benefit from the nomogram model. We classified the ONFH samples into two m6A models according to these 7 regulators through consensus clustering algorithm. After that, we evaluated those two m6A patterns using principal component analysis. We assessed the scores of those two m6A patterns and their relationship with immune infiltration. We observed a higher m6A score of type A than that of type B. Finally, we performed a cross-validation of crucial m6A regulatory factors in ONFH using external datasets and femoral head bone samples. In conclusion, we believed that the m6A pattern could provide a novel diagnostic strategy and offer new insights for molecularly targeted therapy of ONFH.


Assuntos
Adenina/análogos & derivados , Necrose da Cabeça do Fêmur , Cabeça do Fêmur , Humanos , Fêmur , Necrose da Cabeça do Fêmur/genética , Metilação
10.
ACS Appl Mater Interfaces ; 16(10): 12754-12764, 2024 Mar 13.
Artigo em Inglês | MEDLINE | ID: mdl-38382473

RESUMO

Developing high-performance organic-inorganic ultraviolet (UV) photodetectors (PDs) has attracted considerable attention. However, this development has been hindered due to poor directional charge-transfer ratios in transport layers, excessive costs, and an ambiguous underlying mechanism. To tackle these challenges, we constructed a heterojunction of economic Mg-doped ZnO (MgZnO) nanorods and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) [PEDOT:PSS (P:P)] that utilizes dipole field-driven spontaneous polarization to enhance photogenerated charge kinetics. As a result, the proposed heterojunction has an improved noise equivalent power of 3.16 × 10-11 W Hz-1/2), a normalized detection rate (D*) of 8.96 × 109 jones, and external quantum efficiency comparable to other ZnO-based devices. Notably, the prepared PDs showed a photocurrent of 4.8 × 10-3 µA under a faint UV light having an intensity of 1 × 10-5 W cm-2, exceeding the performance of the most state-of-the-art ZnO-based UV sensors. The introduction of Mg into ZnO is responsible for the high performance, as it causes a lattice mismatch and distortion of the Mg-doped ZnO unit cell. It results in improved dipole movement and the creation of a dipole field, accelerating the directional electron-transfer process. Using a dipole field to manipulate the migration and transport of photogenerated carriers represents a promising approach for achieving outstanding performance in UV PDs.

11.
World J Diabetes ; 15(1): 81-91, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-38313851

RESUMO

BACKGROUND: In recent years, the prevalence of obesity and metabolic syndrome in type 1 diabetes (T1DM) patients has gradually increased. Insulin resistance in T1DM deserves attention. It is necessary to clarify the relationship between body composition, metabolic syndrome and insulin resistance in T1DM to guide clinical treatment and intervention. AIM: To assess body composition (BC) in T1DM patients and evaluate the relationship between BC, metabolic syndrome (MS), and insulin resistance in these indi-viduals. METHODS: A total of 101 subjects with T1DM, aged 10 years or older, and with a disease duration of over 1 year were included. Bioelectrical impedance analysis using the Tsinghua-Tongfang BC Analyzer BCA-1B was employed to measure various BC parameters. Clinical and laboratory data were collected, and insulin resistance was calculated using the estimated glucose disposal rate (eGDR). RESULTS: MS was diagnosed in 16/101 patients (15.84%), overweight in 16/101 patients (15.84%), obesity in 4/101 (3.96%), hypertension in 34/101 (33.66%%) and dyslipidemia in 16/101 patients (15.84%). Visceral fat index (VFI) and trunk fat mass were significantly and negatively correlated with eGDR (both P < 0.001). Female patients exhibited higher body fat percentage and visceral fat ratio compared to male patients. Binary logistic regression analysis revealed that significant factors for MS included eGDR [P = 0.017, odds ratio (OR) = 0.109], VFI (P = 0.030, OR = 3.529), and a family history of diabetes (P = 0.004, OR = 0.228). Significant factors for hypertension included eGDR (P < 0.001, OR = 0.488) and skeletal muscle mass (P = 0.003, OR = 1.111). Significant factors for dyslipidemia included trunk fat mass (P = 0.033, OR = 1.202) and eGDR (P = 0.037, OR = 0.708). CONCLUSION: Visceral fat was found to be a superior predictor of MS compared to conventional measures such as body mass index and waist-to-hip ratio in Chinese individuals with T1DM. BC analysis, specifically identifying visceral fat (trunk fat), may play an important role in identifying the increased risk of MS in non-obese patients with T1DM.

12.
bioRxiv ; 2024 Jan 27.
Artigo em Inglês | MEDLINE | ID: mdl-38328123

RESUMO

With the increasing prevalence of antimicrobial-resistant bacterial infections, there is great interest in using lytic bacteriophages (phages) to treat such infections. However, the factors that govern bacteriophage pharmacokinetics in vivo remain poorly understood. Here, we have examined the contribution of neutrophils, the most abundant phagocytes in the body, to the pharmacokinetics of intravenously administered bacteriophage in uninfected mice. A single dose of LPS-5, an antipseudomonal bacteriophage recently used in human clinical trials, was administered intravenously to both wild-type BALB/c and neutropenic ICR mice. Phage concentrations were assessed in peripheral blood and spleen at 0.5, 1, 2, 4, 8, 12, and 24 hours after administration by plaque assay and qPCR. We observed that the phage clearance is only minimally affected by neutropenia. Indeed, the half-life of phages in blood in BALB/c and ICR mice is 3.45 and 3.66 hours, respectively. These data suggest that neutrophil-mediated phagocytosis is not a major determinant of phage clearance. Conversely, we observed a substantial discrepancy in circulating phage levels over time when measured by qPCR versus plaque assay, suggesting that substantial functional inactivation of circulating phages occurs over time. These data indicate that circulating factors, but not neutrophils, inactivate intravenously administered phages.

13.
Chem Asian J ; 19(6): e202300955, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38332680

RESUMO

Activation of inert CO2 molecules for the reverse water gas shift (RWGS) reaction is tackled by incorporating magnesium oxide as a support material for copper, forming a Cu/MgO supported catalyst. The RWGS performance is greatly improved when compared with pure Cu or carbon supported Cu (Cu/C). Operating under a weight hourly space velocity (WHSV) of 300,000 mL ⋅ g-1 ⋅ h-1, the Cu/MgO catalyst demonstrates high activity, maintaining over 70 % equilibrium conversion and nearly 100 % CO selectivity in a temperature range of 300-600 °C. In contrast, both Cu/C and commercial Cu, even at ten-times lower WHSV, can only achieve up to 40 % of the equilibrium conversion and quickly deactivated due to sintering. Based on the studies of in-situ temperature resolved infrared spectroscopy and temperature programmed desorption, the improved RWGS performance is attributed to the unique adsorption behavior of CO2 on Cu/MgO. Density functional theory studies provides a plausible explanation from a surface reaction perspective and reveals the spill-over property of CO2 from MgO to Cu being critical.

14.
Front Neurosci ; 18: 1269577, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38389789

RESUMO

Stem cells offer new therapeutic avenues for the repair and replacement of damaged tissues and organs owing to their self-renewal and multipotent differentiation capabilities. In this paper, we conduct a systematic review of the characteristics of various types of stem cells and offer insights into their potential applications in both cellular and cell-free therapies. In addition, we provide a comprehensive summary of the technical routes of stem cell therapy and discuss in detail current challenges, including safety issues and differentiation control. Although some issues remain, stem cell therapy demonstrates excellent potential in the field of regenerative medicine and provides novel tactics and methodologies for managing a wider spectrum of illnesses and traumas.

15.
Diagnostics (Basel) ; 14(4)2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38396404

RESUMO

Alzheimer's disease (AD) and vascular dementia (VaD) are the two most common forms of dementia. However, their neuropsychological and pathological features often overlap, making it difficult to distinguish between AD and VaD. In addition to clinical consultation and laboratory examinations, clinical dementia diagnosis in Taiwan will also include Tc-99m-ECD SPECT imaging examination. Through machine learning and deep learning technology, we explored the feasibility of using the above clinical practice data to distinguish AD and VaD. We used the physiological data (33 features) and Tc-99m-ECD SPECT images of 112 AD patients and 85 VaD patients in the Taiwanese Nuclear Medicine Brain Image Database to train the classification model. The results, after filtering by the number of SVM RFE 5-fold features, show that the average accuracy of physiological data in distinguishing AD/VaD is 81.22% and the AUC is 0.836; the average accuracy of training images using the Inception V3 model is 85% and the AUC is 0.95. Finally, Grad-CAM heatmap was used to visualize the areas of concern of the model and compared with the SPM analysis method to further understand the differences. This research method can quickly use machine learning and deep learning models to automatically extract image features based on a small amount of general clinical data to objectively distinguish AD and VaD.

16.
Asian J Surg ; 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38383186

RESUMO

BACKGROUND: We aimed to assess the prognostic importance of perinephric fat features in images of patients with non-metastatic renal cell carcinoma (RCC) undergoing surgery. METHODS: We enrolled RCC patients who underwent surgical treatment between 2011 and 2019. Two characteristics, including perinephric fat thickness and perinephric fat stranding, were evaluated using preoperative computed tomography or magnetic resonance images. The association between perinephric fat characteristics and disease progression was examined by Kaplan-Meier survival analysis and Cox regression model. RESULTS: In a multivariate Cox proportional hazards model adjusting for tumor stage, intratumoral necrosis, and neutrophil-to-lymphocyte ratio, we found that patients in the thin perinephric fat group (<1 cm) had a poorer progression-free survival (PFS) compared to the thick perinephric fat group (≥1 cm) (HR 2.8; 95% CI 1.175-6.674, p = 0.02). Additionally, the fat stranding group had a poorer PFS than the non-stranding group (HR 3.852; 95% CI 1.082-13.704, p = 0.037). The non-stranding with thick perinephric fat group exhibits the highest cumulative PFS while the stranding with thin perinephric fat group has the lowest cumulative PFS. In receiver operating characteristic curve analysis, combing these two perinephric fat characteristics with tumor stage can achieve a better discriminatory power than tumor stage alone. CONCLUSIONS: Our study indicates that the evaluation of image-based perinephric fat features is a simple, straightforward, reproducible tool for predicting RCC prognosis and may assist in preoperative risk stratification.

17.
Environ Res ; 246: 118154, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38218520

RESUMO

The management of plastic waste (PW) has become an indispensable worldwide issue because of the enhanced accumulation and environmental impacts of these waste materials. Thermo-catalytic pyrolysis has been proposed as an emerging technology for the valorization of PW into value-added liquid fuels. This review provides a comprehensive investigation of the latest advances in thermo-catalytic pyrolysis of PW for liquid fuel generation, by emphasizing polyethylene, polypropylene, and polystyrene. To this end, the current strategies of PW management are summarized. The various parameters affecting the thermal pyrolysis of PW (e.g., temperature, residence time, heating rate, pyrolysis medium, and plastic type) are discussed, highlighting their significant influence on feed reactivity, product yield, and carbon number distribution of the pyrolysis process. Optimizing these parameters in the pyrolysis process can ensure highly efficient energy recovery from PW. In comparison with non-catalytic PW pyrolysis, catalytic pyrolysis of PW is considered by discussing mechanisms, reaction pathways, and the performance of various catalysts. It is established that the introduction of either acid or base catalysts shifts PW pyrolysis from the conventional free radical mechanism towards the carbonium ion mechanism, altering its kinetics and pathways. This review also provides an overview of PW pyrolysis practicality for scaling up by describing techno-economic challenges and opportunities, environmental considerations, and presenting future outlooks in this field. Overall, via investigation of the recent research findings, this paper offers valuable insights into the potential of thermo-catalytic pyrolysis as an emerging strategy for PW management and the production of liquid fuels, while also highlighting avenues for further exploration and development.


Assuntos
Poliestirenos , Pirólise , Polienos , Polietileno , Plásticos
18.
Colloids Surf B Biointerfaces ; 234: 113760, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38244484

RESUMO

Recently, carbon quantum dots (CQDs) have become popular because of their simple synthesis and potential applications. Although CQDs have high biocompatibility, their biotoxicity must be verified to reduce the possible risks associated with large-scale application. In this study, the hepatotoxicity of three CQD types, namely diammonium citrate (AC)-based (CQDs-AC), spermidine trihydrochloride (Spd)-based (CQDs-Spd), and AC- and Spd-based CQDs (CQDs-AC/Spd), were evaluated in vivo and in vitro. It was observed in vivo that CQDs-Spd and CQDs-AC/Spd, but not CQDs-AC, caused histopathological damage, including liver steatosis and mild mixed inflammatory cell infiltration; however, reduced liver function was only observed in CQD-Spd-treated mice. The in vitro results revealed that only CQDs-Spd significantly decreased the number of viable HepG2 cells (NADH depletion) and induced oxidative stress (heme oxygenase-1 activation) after 24 h of exposure, which promoted inflammatory factor secretion (NF-κB activation). Additionally, decreasing zonula occludens-2 and α1-antitrypsin protein expression in HepG2 cells suggested that CQD-Spd exposure increases the risk of liver diseases. Our results revealed that CQDs-Spd had greater hepatotoxic potential than CQDs-AC and CQDs-AC/Spd, which might be attributable to their high positive surface charge. Overall, the risk of CQD-induced hepatotoxic risk must be considered when applying positively charged CQDs.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Pontos Quânticos , Camundongos , Animais , Humanos , Pontos Quânticos/toxicidade , Carbono/farmacologia , Espermidina , Células Hep G2 , Doença Hepática Induzida por Substâncias e Drogas/etiologia
19.
Ecotoxicol Environ Saf ; 271: 115846, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38242045

RESUMO

As a key component of plant nitrogen-fixing enzymes and a variety of human coenzyme factors, molybdenum (Mo) plays an essential role in supporting both plant growth and human health. Soil is a key medium for the cycling of Mo in the biosphere. However, the driving anthropogenic and natural factors governing the spatial distribution of Mo in soil and their interactions are not well understood. To determine the factors that affect the spatial patterns of Mo in topsoil, 6980 samples were collected from the Longitudinal Range-Gorge Region (Linshui County, Sichuan Province, China). In this area, tall mountains are adjacent to deep valleys. Topsoil with enriched Mo is mostly distributed in mountainous areas. The most important factors influencing Mo in topsoil are soil parent materials (q = 0.482), altitude (q = 0.256), and soil type (q = 0.259). There are synergistic effects among the various driving factors [q(X1 âˆ© X2) > Max[q(X1), q(X2)]]. The Geodetector model was used to validate the magnitude of the interaction effects. The contribution to interacting factors is nonlinearly enhanced when the contribution of a single factor was low (any two factors of aspect, road distance, land use type, and S). The contribution to interacting factors is enhanced bidirectionally when the contribution of a single factor was high (any two factors of altitude, soil type, soil parent material, OM, and TFe2O3). When the contribution of one factor is high and the other is low, the contributing to interacting factors is mostly enhanced bidirectionally and a few are nonlinearly enhanced.


Assuntos
Molibdênio , Poluentes do Solo , Humanos , Molibdênio/análise , China , Solo , Altitude , Poluentes do Solo/análise
20.
Bioresour Technol ; 395: 130339, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244936

RESUMO

Using edible lipids for biodiesel production has been criticized, causing biodiesel production from inedible food resources to be desirable. Lipid extraction must be prioritized to produce biodiesel using an acid/base-catalyzed transesterification process, but this conversion process suffers from technical reliability. Therefore, this study introduced non-catalytic conversion of oil-bearing biomass into biodiesel. Apricot seeds were used as a model compound (oil content 44.3 wt%). The non-catalytic transesterification of apricot seed oil recovered 98.28 wt% biodiesel at 360 °C for 1 min, while alkali-catalysis of apricot seed oil recovered 91.84 wt% at 63 °C for 60 min. The direct conversion of apricot seeds into biodiesel was attempted. The trends in the yields of biodiesel from apricot seeds and seed oil obtained by non-catalytic transesterification as a function of reaction temperature were similar. The yield of biodiesel from apricot seed was 43.06 wt%, suggesting that 97.20 wt% of lipids were converted into biodiesel.


Assuntos
Prunus armeniaca , Biocombustíveis , Reprodutibilidade dos Testes , Esterificação , Ácidos Graxos , Sementes , Óleos de Plantas , Catálise
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