Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 511
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
J Am Chem Soc ; 146(33): 23044-23053, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39126393

RESUMEN

Li-alloying reactions facilitate the incorporation of a large number of Li atoms into the crystalline structures of electrodes, such as black phosphorus (BP). However, the reactions inevitably induce multistep phase transitions characterized by drastic atomic rearrangements and lattice collapse. Despite many theoretical and experimental studies on alloying mechanisms, long-term debates persist regarding the structures of the intermediate phases, the accurate pathways of phase transitions, the formation of specific configurations, and alloying/dealloying reversibility. Here, through a combination of operando electron diffraction measurements and ab initio simulations at the atomic and electronic scales, we identify key factors that govern the severe structural changes during alloying-dealloying reactions in BP. P-P bonds of three-bond P atoms are continuously broken during lithiation, generating two-bond P atoms with a high ability to accept inserted electrons and Li ions. Consequently, the pristine layered structure in BP is transformed to P7 cages in Li3P7, which then evolve to chain configurations in LiP and finally to isolated P atoms in Li3P. Specifically, the preferential formation of the P7 cage results from its lowest binding energy with three Li ions compared to other cage isomers. Furthermore, only LiP can be reversibly transformed to the crystalline structure of Li3P7 during charge, but it is thermodynamically favorable for Li3P7 and Li3P intermediates to be delithiated to amorphous structures. Our findings offer unique insights into the alloying mechanisms and deepen the fundamental understanding of alloying anode systems.

2.
Environ Sci Technol ; 58(9): 4438-4449, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38330552

RESUMEN

Dechlorination of chloropyridines can eliminate their detrimental environmental effects. However, traditional dechlorination technology cannot efficiently break the C-Cl bond of chloropyridines, which is restricted by the uncontrollable nonselective species. Hence, we propose the carbonate species-activated hydrogen peroxide (carbonate species/H2O2) process wherein the selective oxidant (peroxymonocarbonate ion, HCO4-) and selective reductant (hydroperoxide anion, HO2-) controllably coexist by manipulation of reaction pH. Taking 2-chloropyridine (Cl-Py) as an example, HCO4- first induces Cl-Py into pyridine N-oxidation intermediates, which then suffer from the nucleophilic dechlorination by HO2-. The obtained dechlorination efficiencies in the carbonate species/H2O2 process (32.5-84.5%) based on the cooperation of HCO4- and HO2- are significantly higher than those in the HO2--mediated sodium hydroxide/hydrogen peroxide process (0-43.8%). Theoretical calculations confirm that pyridine N-oxidation of Cl-Py can effectively lower the energy barrier of the dechlorination process. Moreover, the carbonate species/H2O2 process exhibits superior anti-interference performance and low electric energy consumption. Furthermore, Cl-Py is completely detoxified via the carbonate species/H2O2 process. More importantly, the carbonate species/H2O2 process is applicable for efficient dehalogenation of halogenated pyridines and pyrazines. This work offers a simple and useful strategy to enhance the dehalogenation efficiency of halogenated organics and sheds new insights into the application of the carbonate species/H2O2 process in practical environmental remediation.


Asunto(s)
Peróxido de Hidrógeno , Piridinas , Peróxido de Hidrógeno/química , Oxidación-Reducción , Carbonatos
3.
BMC Infect Dis ; 24(1): 592, 2024 Jun 17.
Artículo en Inglés | MEDLINE | ID: mdl-38886634

RESUMEN

BACKGROUND: As an emerging infectious disease with a heterogenous and uncertain transmission pattern, coronavirus disease 2019 (COVID-19) has created a catastrophe in healthcare-associated infections (HAIs) and posed a significant challenge to infection control practices (ICPs) in healthcare settings. While the unique characteristics of psychiatric patients and clinical settings may make the implementation of ICPs difficult, evidence is lacking for compliance with ICPs among healthcare workers (HCWs) in a psychiatric setting during the COVID-19 pandemic. METHODS: A cross-sectional multi-method study based on participant unobtrusive observation coupled with the completion of a self-administered ICP survey was conducted to assess compliance with ICPs among HCWs in a psychiatric inpatient ward in a regional hospital. An online checklist, called eRub, was used to record the performance of HCWs in hand hygiene (HH) and other essential ICPs. Furthermore, a well-validated questionnaire (i.e., Compliance with Standard Precautions Scale, CSPS) was used to collect the participants' self-reported ICP compliance for later comparison. RESULTS: A total of 2,670 ICP opportunities were observed from January to April 2020. The overall compliance rate was 42.6%. HCWs exhibited satisfactory compliance to the wearing of mask (91.2%) and the handling of clinical waste (87.5%); suboptimal compliance to the handling of sharp objects (67.7%) and linen (72.7%); and poor compliance to HH (3.3%), use of gloves (40.9%), use of personal protective equipment (20%), and disinfection of used surface/area (0.4%). The compliance rates of the nurses and support staff to HH were significantly different (χ2 = 123.25, p < 0.001). In the self-reported survey, the overall compliance rate for ICPs was 64.6%. CONCLUSION: The compliance of HCWs in a psychiatric inpatient ward to ICPs during the COVID-19 pandemic ranged from poor to suboptimal. This result was alarming. Revisions of current ICP guidelines and policies that specifically target barriers in psychiatric settings will be necessary.


Asunto(s)
COVID-19 , Adhesión a Directriz , Personal de Salud , Control de Infecciones , Autoinforme , Humanos , COVID-19/prevención & control , COVID-19/epidemiología , Estudios Transversales , Control de Infecciones/métodos , Personal de Salud/psicología , Adhesión a Directriz/estadística & datos numéricos , Encuestas y Cuestionarios , Masculino , SARS-CoV-2 , Femenino , Infección Hospitalaria/prevención & control , Higiene de las Manos/estadística & datos numéricos , Adulto , Persona de Mediana Edad , Servicio de Psiquiatría en Hospital , Equipo de Protección Personal/estadística & datos numéricos
4.
Acta Pharmacol Sin ; 45(8): 1618-1631, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38641745

RESUMEN

Hypertension is a prominent contributor to vascular injury. Deubiquinatase has been implicated in the regulation of hypertension-induced vascular injury. In the present study we investigated the specific role of deubiquinatase YOD1 in hypertension-induced vascular injury. Vascular endothelial endothelial-mesenchymal transition (EndMT) was induced in male WT and YOD1-/- mice by administration of Ang II (1 µg/kg per minute) via osmotic pump for four weeks. We showed a significantly increased expression of YOD1 in mouse vascular endothelial cells upon Ang II stimulation. Knockout of YOD1 resulted in a notable reduction in EndMT in vascular endothelial cells of Ang II-treated mouse; a similar result was observed in Ang II-treated human umbilical vein endothelial cells (HUVECs). We then conducted LC-MS/MS and co-immunoprecipitation (Co-IP) analyses to verify the binding between YOD1 and EndMT-related proteins, and found that YOD1 directly bound to ß-catenin in HUVECs via its ovarian tumor-associated protease (OTU) domain, and histidine at 262 performing deubiquitination to maintain ß-catenin protein stability by removing the K48 ubiquitin chain from ß-catenin and preventing its proteasome degradation, thereby promoting EndMT of vascular endothelial cells. Oral administration of ß-catenin inhibitor MSAB (20 mg/kg, every other day for four weeks) eliminated the protective effect of YOD1 deletion on vascular endothelial injury. In conclusion, we demonstrate a new YOD1-ß-catenin axis in regulating Ang II-induced vascular endothelial injury and reveal YOD1 as a deubiquitinating enzyme for ß-catenin, suggesting that targeting YOD1 holds promise as a potential therapeutic strategy for treating ß-catenin-mediated vascular diseases.


Asunto(s)
Angiotensina II , Células Endoteliales de la Vena Umbilical Humana , Ratones Endogámicos C57BL , Ratones Noqueados , beta Catenina , Animales , beta Catenina/metabolismo , Humanos , Angiotensina II/farmacología , Angiotensina II/metabolismo , Masculino , Ratones , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Endotelial-Mesenquimatosa
5.
Ren Fail ; 46(2): 2384586, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39082695

RESUMEN

Peritoneal dialysis (PD) is a widely used sustainable kidney replacement therapy. Prolonged use of PD fluids is associated with mesothelial-mesenchymal transition, peritoneal fibrosis, and eventual ultrafiltration (UF) failure. However, the impact of pressure on the peritoneum remains unclear. In the present study, we hypothesized increased pressure is a potential contributing factor to peritoneal fibrosis and investigated the possible mechanisms. In vitro experiments found that pressurization led to a mesenchymal phenotype, the expression of fibrotic markers and inflammatory factors in human mesothelial MeT-5A cells. Pressure also increased cell proliferation and augmented cell migration potential in MeT-5A cells. The mouse PD model and human peritoneum equilibrium test (PET) data both showed a positive association between higher pressure and increased small solute transport, along with decreased net UF. Mechanistically, we found that significant upregulation of CD44 in mesothelial cells upon pressurization. Notably, the treatment of CD44 neutralizing antibodies prevented pressure-induced phenotypic changes in mesothelial cells, while a CD44 inhibitor oligo-fucoidan ameliorated pressure-induced peritoneal thickening, fibrosis, and inflammation in PD mice. To conclude, intraperitoneal pressure results in peritoneal fibrosis in PD via CD44-mediated mesothelial changes and inflammation. CD44 blockage can be utilized as a novel preventive approach for PD-related peritoneal fibrosis and UF failure.


Asunto(s)
Receptores de Hialuranos , Diálisis Peritoneal , Fibrosis Peritoneal , Peritoneo , Transducción de Señal , Fibrosis Peritoneal/metabolismo , Fibrosis Peritoneal/etiología , Fibrosis Peritoneal/patología , Animales , Ratones , Receptores de Hialuranos/metabolismo , Humanos , Peritoneo/patología , Peritoneo/metabolismo , Diálisis Peritoneal/efectos adversos , Modelos Animales de Enfermedad , Inflamación/metabolismo , Presión/efectos adversos , Masculino , Proliferación Celular , Transición Epitelial-Mesenquimal , Ratones Endogámicos C57BL , Línea Celular , Movimiento Celular
6.
J Formos Med Assoc ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38777672

RESUMEN

Kidney transplant recipients have an increased risk of cytomegalovirus (CMV) infection and disease. A strategy for mitigating the risk of CMV infection in kidney transplant recipients has not yet been established in Taiwan. The Transplantation Society of Taiwan aimed to develop a consensus by expert opinion on the prevention and management of CMV infection. Based on the results of Consensus Conference, we suggested low-dose valganciclovir prophylaxis (450 mg once daily) for kidney transplant recipients. The prophylaxis duration was ≥6 months for high-risk (D+/R-) patients and 3 months for moderate-risk (R+) patients. Even for low-risk (D-/R-) patients, prophylaxis for at least 3 months is recommended because of the high seroprevalence of CMV in Taiwan. CMV prophylaxis was suggested after anti-thymocyte globulin treatment but not after methylprednisolone pulse therapy. Routine surveillance after prophylaxis, secondary prophylaxis after CMV disease treatment, and mTOR inhibitors for primary CMV prophylaxis were not recommended. Letermovir and marabavir are emerging CMV agents used for prophylaxis and refractory CMV disease. CMV immunoglobulins have been used to treat refractory CMV disease in Taiwan. We hope this consensus will help professionals manage patients with CMV in Taiwan to improve the quality of care.

7.
Nano Lett ; 23(17): 8331-8338, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37647133

RESUMEN

The great interest in large-scale electrochemical water splitting toward clean hydrogen has spurred large numbers of studies on developing cost-efficient and high-performance bifunctional electrocatalysts. Here, a Prussian-blue-analogue-derived method is proposed to prepare honeycomb-like ultrathin and heterogeneous Co2P-Fe2P nanosheets on nickel foam, showing low overpotentials of 0.080, 0.088, and 0.109 V for the hydrogen evolution reaction (HER) at 10 mA cm-2 as well as 0.290, 0.370, and 0.730 V for the oxygen evolution reaction (OER) at 50 mA cm-2 in alkaline, acidic, and neutral electrolytes, respectively. When directly applied for universal-pH water electrolysis, excellent performances are achieved especially at ultralow voltages of 1.45 V at 10 mA cm-2, 1.66 V at 100 mA cm-2, and 1.79 V at 500 mA cm-2 under alkaline conditions. In situ Raman spectroscopy measurements demonstrate that the excellent HER performance can be attributed to heterogeneous Co2P-Fe2P while the ultrahigh alkaline OER performance originates from reconstruction-induced oxyhydroxides.

8.
Int J Nurs Pract ; 30(2): e13233, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38230568

RESUMEN

AIMS: This study aimed to (i) evaluate the effectiveness of mindfulness-based interventions in improving self-efficacy, reducing stress and anxiety among peritoneal dialysis patients, and (ii) compare the most effective method of mindfulness based interventions. METHODS: This randomized three-arm controlled trial recruited first-time peritoneal dialysis patients from the peritoneal dialysis outpatient clinic in Singapore. Patients were randomly allocated to either video-assisted mindfulness training, therapist-assisted mindfulness training or treatment-as-usual. All groups received 4.5 days of structured peritoneal dialysis training at the peritoneal dialysis centre, while video-assisted mindfulness training and therapist-assisted mindfulness training groups were taught additional mindfulness-based techniques. The perceived stress scale, self-efficacy, and anxiety (State and Trait Anxiety Inventory) were measured at baseline, 4- and 12 weeks post-randomization, using reliable and valid instruments. RESULTS: Thirty-nine patients were recruited (13 in each group). All the therapies showed a significant time trend in anxiety. Only therapist- and video-assisted mindfulness training showed a significant trend in perceived stress scale scores but not treatment-as-usual. All Intervention X Time interactions were not significant. Patients in therapist- and video-assisted mindfulness training groups had reduced perceived stress scale scores compared to treatment-as-usual at week 12. CONCLUSION: This study demonstrated the potential of mindfulness-based interventions in reducing stress among first-time PD patients.


Asunto(s)
Atención Plena , Diálisis Peritoneal , Pruebas Psicológicas , Autoinforme , Humanos , Atención Plena/métodos , Singapur , Instituciones de Atención Ambulatoria , Tecnología
9.
Small ; 19(36): e2301378, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37127873

RESUMEN

Flexible piezoresistive sensors with biological structures are widely exploited for high sensitivity and detection. However, the conventional bionic structure pressure sensors usually suffer from irreconcilable conflicts between high sensitivity and wide detection response range. Herein, a triple periodic minimum surface (TPMS) structure sensor is proposed based on parametric structural design and 3D printing techniques. Upon tailoring of the dedicated structural parameters, the resulting sensors exhibit superior compression durability, high sensitivity, and ultra-high detection range, that enabling it meets the needs of various scenes. As a model system, TPMS structure sensor with 40.5% porosity exhibits an ultra-high sensitivity (132 kPa-1 in 0-5.7 MPa), wide detection strain range (0-31.2%), high repeatability and durability (1000 cycles in 4.41 MPa, 10000 s in 1.32 MPa), and low detection limit (1% in 80 kPa). The stress/strain distributions have been identified using finite element analysis. Toward practical applications, the TPMS structural sensors can be applied to detect human activity and health monitoring (i.e., voice recognition, finger pressure, sitting, standing, walking, and falling down behaviors). The synergistic effects of MWCNTs and MXene conductive network also ensure the composite further being utilized for electromagnetic interference shielding applications.

10.
J Child Psychol Psychiatry ; 64(12): 1720-1734, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37222162

RESUMEN

BACKGROUND: Youth anxiety and depression have long been combined within the empirically derived internalizing syndrome. The two conditions show substantial comorbidity, symptom co-occurrence, and overlap in treatment procedures, but paradoxically diverge in psychotherapy outcomes: strong, positive effects for anxiety and weak effects for depression. METHODS: Drawing on recent research, we examine candidate explanations for this paradox to help identify strategies for addressing it by improving outcomes for youth depression. RESULTS: Candidate explanations include that youth depression, compared with youth anxiety, has more varied comorbidities and more heterogeneous symptom combinations, has greater uncertainty regarding mediators and mechanisms of change, is treated with more complex and potentially confusing protocols, and has characteristics that may impede client engagement. Candidate strategies for shrinking the psychotherapy effectiveness gap include personalizing through transdiagnostic modular treatment, simplifying therapy by focusing on empirically supported principles of change, developing effective strategies for engaging family members as intervention allies, using shared decision-making to inform clinical decisions and boost client engagement, capitalizing on youth-friendly technological advances, and shortening and digitizing treatments to enhance their accessibility and appeal. CONCLUSIONS: Recent advances suggest explanations for the internalizing paradox, which in turn suggest strategies for shrinking the youth anxiety-depression psychotherapy outcome gap; these form an agenda for a promising new era of research.


Asunto(s)
Ansiedad , Depresión , Humanos , Adolescente , Depresión/terapia , Ansiedad/terapia , Trastornos de Ansiedad/terapia , Psicoterapia/métodos , Comorbilidad
11.
J Org Chem ; 88(4): 2288-2295, 2023 Feb 17.
Artículo en Inglés | MEDLINE | ID: mdl-36738288

RESUMEN

A simple and practical electron donor-acceptor (EDA) strategy to synthesize various 3-alkylated coumarins from easily available coumarins and naturally abundant carboxylic acids under photocatalyst-, oxidant-, and additive-free and mild conditions is reported. Using Na2S as the catalytic electron donor, a series of primary, secondary, and tertiary carbon radicals can be efficiently generated, and the EDA complex can be regenerated without an alkaline additive.

12.
Fish Shellfish Immunol ; 136: 108703, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36948366

RESUMEN

NK-lysin (NKL) is a positively charged antimicrobial peptide with broad-spectrum bactericidal activities. In this study, the cDNA sequence of NKL (TmNKL) from black scraper (Thamnaconus modestus) was cloned, which encodes a predicted polypeptide of 150 amino acids that contains a surfactant protein B domain with three disulfide bonds. Phylogenetically, TmNKL was most closely related to its teleost counterpart from tiger puffer (Takifugu rubripes). Expression analysis demonstrated that TmNKL transcripts were constitutively expressed in all tested tissues, with the highest expression levels in the gills. Its expression was significantly upregulated in the gills, head kidney, and spleen after infection with Vibrio parahaemolyticus. A linear peptide (TmNKLP40L) and a disulfide-type peptide (TmNKLP40O) were further synthesized and results showed that disulfide bonds are not essential for bactericidal activities of TmNKL, and that both forms of TmNKL exhibited potent bactericidal activities against 4 gram- negative bacteria, including V. parahaemolyticus, V. alginolyticus, Edwardsiella tarda, and V. harveyi. Observed antimicrobial activities are likely due to the effects of TmNKLP40L and TmNKLP40O treatment on disrupting the integrity of both inner and outer membrane of V. parahaemolyticus, resulting in hydrolysis of bacterial genomic DNA. Damaged cell membranes and leakage of intracellular contents were further confirmed using scanning and transmission microscopy. Moreover, administration of 1.0 µg/g TmNKLP40L or TmNKLP40O significantly decreased bacterial load in tissues and thus, pronouncedly enhanced the survival of V. parahaemolyticus-infected fish. Overall, our results demonstrated that TmNKL is a potent innate effector and provides protective effects against bacterial infection.


Asunto(s)
Antiinfecciosos , Enfermedades de los Peces , Tetraodontiformes , Animales , Proteínas de Peces/química , Péptidos , Bacterias Gramnegativas , Antiinfecciosos/farmacología , Enfermedades de los Peces/microbiología
13.
Nanotechnology ; 34(16)2023 Feb 06.
Artículo en Inglés | MEDLINE | ID: mdl-36657162

RESUMEN

Staphylococcus aureus (S. aureus)forms biofilm that causes periprosthetic joint infections and osteomyelitis (OM) which are the intractable health problems in clinics. The silver-containing nanoparticles (AgNPs) are antibacterial nanomaterials with less cytotoxicity than the classic Ag compounds. Likewise, gold nanoparticles (AuNPs) have also been demonstrated as excellent nanomaterials for medical applications. Previous studies have showed that both AgNPs and AuNPs have anti-microbial or anti-inflammatory properties. We have developed a novel green chemistry that could generate the AuAg nanocomposites, through the reduction of tannic acid (TNA). The bioactivity of the nanocomposites was investigated inS. aureusbiofilm-exposed human osteoblast cells (hFOB1.19). The current synthesis method is a simple, low-cost, eco-friendly, and green chemistry approach. Our results showed that the AuAg nanocomposites were biocompatible with low cell toxicity, and did not induce cell apoptosis nor necrosis in hFOB1.19 cells. Moreover, AuAg nanocomposites could effectively inhibited the accumulation of reactive oxygen species (ROS) in mitochondria and in rest of cellular compartments after exposing to bacterial biofilm (by reducing 0.78, 0.77-fold in the cell and mitochondria, respectively). AuAg nanocomposites also suppressed ROS-triggered inflammatory protein expression via MAPKs and Akt pathways. The current data suggest that AuAg nanocomposites have the potential to be a good therapeutic agent in treating inflammation in bacteria-infected bone diseases.


Asunto(s)
Nanopartículas del Metal , Nanocompuestos , Humanos , Oro/farmacología , Nanopartículas del Metal/química , Staphylococcus aureus , Especies Reactivas de Oxígeno/metabolismo , Antibacterianos/farmacología , Antibacterianos/química , Bacterias , Nanocompuestos/química , Biopelículas , Inflamación/tratamiento farmacológico , Pruebas de Sensibilidad Microbiana
14.
Environ Sci Technol ; 57(12): 5034-5045, 2023 03 28.
Artículo en Inglés | MEDLINE | ID: mdl-36916663

RESUMEN

Traditional methods cannot efficiently recover Cu from Cu(II)-EDTA wastewater and encounter the formation of secondary contaminants. In this study, an ozone/percarbonate (O3/SPC) process was proposed to efficiently decomplex Cu(II)-EDTA and simultaneously recover Cu. The results demonstrate that the O3/SPC process achieves 100% recovery of Cu with the corresponding kobs value of 0.103 min-1 compared with the typical •OH-based O3/H2O2 process (81.2%, 0.042 min-1). The carbonate radical anion (CO3•-) is generated from the O3/SPC process and carries out the targeted attack of amino groups of Cu(II)-EDTA for decarboxylation and deamination processes, resulting in successive cleavage of Cu-O and Cu-N bonds. In comparison, the •OH-based O3/H2O2 process is predominantly responsible for the breakage of Cu-O bonds via decarboxylation and formic acid removal. Moreover, the released Cu(II) can be transformed into stable copper precipitates by employing an endogenous precipitant (CO32-), accompanied by toxic-free byproducts in the O3/SPC process. More importantly, the O3/SPC process exhibits excellent metal recovery in the treatment of real copper electroplating wastewater and other metal-EDTA complexes. This study provides a promising technology and opens a new avenue for the efficient decomplexation of metal-organic complexes with simultaneous recovery of valuable metal resources.


Asunto(s)
Complejos de Coordinación , Ozono , Contaminantes Químicos del Agua , Aguas Residuales , Cobre , Ácido Edético/química , Peróxido de Hidrógeno , Oxidación-Reducción , Carbonatos , Contaminantes Químicos del Agua/química
15.
Environ Sci Technol ; 57(46): 18172-18182, 2023 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-37129473

RESUMEN

China's nitrogen oxide (NOx) emissions have undergone significant changes over the past few decades. However, nonfossil fuel NOx emissions are not yet well constrained in urban environments, resulting in a substantial underestimation of their importance relative to the known fossil fuel NOx emissions. We developed an approach using machine learning that is accurate enough to generate a long time series of the nitrogen isotopic composition (δ15N) of atmospheric nitrate using high-level accuracies of air pollutants and meteorology data. Air temperature was found to be the critical driver of the variation of nitrate δ15N at daily resolution based on this approach, while significant reductions of aerosol and its precursor emissions played a key role in the change of nitrate δ15N on the yearly scale. Predictions from this model found a significant decrease in nitrate δ15N in Chinese megacities (Beijing and Guangzhou as representative cities in the north and south, respectively) since 2013, implying an enhanced contribution of nonfossil fuel NOx emissions to nitrate aerosols (up to 22%-26% in 2021 from 18%-22% in 2013 quantified by an isotope mixing model), as confirmed by the Weather Research and Forecasting model coupled with online chemistry (WRF-Chem) simulation. Meanwhile, the declining contribution in coal combustion (34%-39% in 2013 to 31%-34% in 2021) and increasing contribution of natural gas combustion (11%-14% in 2013 to 14%-17% in 2021) demonstrated the transformation of China's energy structure from coal to natural gas. This approach provides missing records for exploring long-term variability in the nitrogen isotope system and may contribute to the study of the global reactive nitrogen biogeochemical cycle.


Asunto(s)
Contaminantes Atmosféricos , Nitratos , Nitratos/análisis , Gas Natural , Estaciones del Año , Monitoreo del Ambiente/métodos , China , Contaminantes Atmosféricos/análisis , Carbón Mineral/análisis , Óxido Nítrico , Isótopos de Nitrógeno/análisis , Aerosoles/análisis , Material Particulado/análisis
16.
Phys Chem Chem Phys ; 25(12): 8934-8947, 2023 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-36916876

RESUMEN

The mechanism of Sn and Nb influence on the fraction of tetragonal ZrO2 in oxide films on Zr alloys and their influence mechanism on corrosion resistance of Zr alloys, despite decades of research, are ambiguous due to the lack of kinetic knowledge of phase evolution of ZrO2 with doping. Using stochastic surface walking and density functional theory calculations, we investigate the influence of Nb and Sn on the stability of tetragonal (t) and monoclinic (m) ZrO2, and t-m phase transition in oxide films. We found that though Nb and Sn result in similar apparent variation trends in the t-phase fraction in oxide films, their influences on t-m phase transition differ significantly, which is the underlying origin of different influences of the t-phase fraction in oxide films on the corrosion resistance of Zr alloys with Sn and Nb alloying. These results clarify an important aspect of the relationship between the microstructure and corrosion resistance of Zr alloys.

17.
Int J Med Sci ; 20(4): 444-454, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37057216

RESUMEN

The development of endocrine therapy resistance in the luminal A subtype of breast cancer is related to the appearance of protective autophagy. The bioactive component from the root of licorice, 18ß-glycyrrhetinic acid (18ß-GA), has many antitumor properties. Whether 18ß-GA can modulate autophagy to inhibit proliferation of the luminal A subtype is still unclear. The proportion of apoptosis caused by 18ß-GA in MCF-7 and T-47D cells was determined using flow cytometry. The autophagy marker, LC3-II conversion, was investigated using Western blotting, and a PremoTM Tandem Autophagy Sensor Kit. We found that the concentration (150-µM) of 18ß-GA caused caspase-dependent apoptosis and LC3-II accumulation or blocked autophagic flux. Moreover, 18ß-GA-mediated apoptosis was improved using rapamycin but reversed by 3-methyladenine (3-MA) addition. The phosphorylation level of Jun-amino-terminal kinase (JNK) was increased significantly in the 18ß-GA treatment and combined incubation using rapamycin. A JNK inhibitor (SP600125) significantly inhibited 18ß-GA-mediated apoptosis, LC3-II accumulation and rescued the numbers of MCF-7 and T-47D colony formation. Especially, 18ß-GA can inhibit xenograft tumor growth in BALB/c nude mice. These data indicate the combination of 18ß-GA with rapamycin or 3-MA can sensitize or decrease MCF-7 and T-47D cells to 18ß-GA-induced apoptosis, respectively. 18ß-GA modulated autophagy is cytotoxic to luminal A subtype breast cancer cells through apoptosis promotion and JNK activation.


Asunto(s)
Antineoplásicos , Ácido Glicirretínico , Neoplasias , Animales , Ratones , Humanos , Ratones Desnudos , Ácido Glicirretínico/farmacología , Ácido Glicirretínico/uso terapéutico , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Apoptosis , Sirolimus/farmacología , Autofagia
18.
Annu Rev Clin Psychol ; 19: 79-105, 2023 05 09.
Artículo en Inglés | MEDLINE | ID: mdl-36750262

RESUMEN

Intervention scientists have published more than 600 randomized controlled trials (RCTs) of youth psychotherapies. Four decades of meta-analyses have been used to synthesize the RCT findings and identify scientifically and clinically significant patterns. These meta-analyses have limitations, noted herein, but they have advanced our understanding of youth psychotherapy, revealing (a) mental health problems for which our interventions are more and less successful (e.g., anxiety and depression, respectively); (b) the beneficial effects of single-session interventions, interventions delivered remotely, and interventions tested in low- and middle-income countries; (c) the association of societal sexism and racism with reduced treatment benefit in majority-girl and majority-Black groups; and, importantly, (d) the finding that average youth treatment benefit has not increased across five decades of research, suggesting that new strategies may be needed. Opportunities for the future include boosting relevance to policy and practice and using meta-analysis to identify mechanisms of change and guide personalizing of treatment.


Asunto(s)
Psicoterapia , Telemedicina , Femenino , Humanos , Adolescente , Ansiedad , Trastornos de Ansiedad
19.
Nanomedicine ; 48: 102652, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36623714

RESUMEN

Metal-organic frameworks (MOFs) have emerged as attractive candidates in cancer theranostics due to their ability to envelop magnetic nanoparticles, resulting in reduced cytotoxicity and high porosity, enabling chemodrug encapsulation. Here, FeAu alloy nanoparticles (FeAu NPs) are synthesized and coated with MIL-100(Fe) MOFs to fabricate FeAu@MOF nanostructures. We encapsulated Doxorubicin within the nanostructures and evaluated the suitability of this platform for medical imaging and cancer theranostics. FeAu@MOF nanostructures (FeAu@MIL-100(Fe)) exhibited superparamagnetism, magnetic hyperthermia behavior and displayed DOX encapsulation and release efficiency of 69.95 % and 97.19 %, respectively, when stimulated with alternating magnetic field (AMF). In-vitro experiments showed that AMF-induced hyperthermia resulted in 90 % HSC-3 oral squamous carcinoma cell death, indicating application in cancer theranostics. Finally, in an in-vivo mouse model, FeAu@MOF nanostructures improved image contrast, reduced tumor volume by 30-fold and tumor weight by 10-fold, which translated to enhancement in cumulative survival, highlighting the prospect of this platform for oral cancer treatment.


Asunto(s)
Carcinoma , Hipertermia Inducida , Estructuras Metalorgánicas , Neoplasias de la Boca , Nanoestructuras , Animales , Ratones , Estructuras Metalorgánicas/química , Medicina de Precisión , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Doxorrubicina/química , Neoplasias de la Boca/diagnóstico por imagen , Neoplasias de la Boca/tratamiento farmacológico , Diagnóstico por Imagen , Fenómenos Magnéticos , Nanomedicina Teranóstica
20.
J Formos Med Assoc ; 122(10): 976-985, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37183074

RESUMEN

Solid organ transplant recipients have an increased risk of tuberculosis (TB). Due to the use of immunosuppressants, the incidence of TB among solid organ transplant recipients has been consistently reported to be higher than that among the general population. TB frequently develops within the first year after transplantation when a high level of immunosuppression is maintained. Extrapulmonary TB and disseminated TB account for a substantial proportion of TB among solid organ transplant recipients. Treatment of TB among recipients is complicated by the drug-drug interactions between anti-TB drugs and immunosuppressants. TB is associated with an increased risk of graft rejection, graft failure and mortality. Detection and management of latent TB infection among solid organ transplant candidates and recipients have been recommended. However, strategy to mitigate the risk of TB among solid organ transplant recipients has not yet been established in Taiwan. To address the challenges of TB among solid organ transplant recipients, a working group of the Transplantation Society of Taiwan was established. The working group searched literatures on TB among solid organ transplant recipients as well as guidelines and recommendations, and proposed interventions to strengthen TB prevention and care among solid organ transplant recipients.


Asunto(s)
Trasplante de Órganos , Tuberculosis , Humanos , Taiwán/epidemiología , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Tuberculosis/epidemiología , Trasplante de Órganos/efectos adversos , Antituberculosos/uso terapéutico , Inmunosupresores/efectos adversos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA