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1.
Angew Chem Int Ed Engl ; : e202409779, 2024 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-38989722

RESUMO

Bromine chemistry is responsible for the catalytic ozone destruction in the atmosphere. The heterogeneous reactions of sea-salt aerosols are the main abiotic sources of reactive bromine in the atmosphere. Here, we present a novel mechanism for the activation of bromide ions (Br-) by O2 and H2O in the absence of additional oxidants. The laboratory and theoretical calculation results demonstrated that under dark conditions, Br-, O2 and H3O+ could spontaneously generate Br and HO2 radicals through a proton-electron transfer process at the air‒water interface and in the liquid phase. Our results also showed that light and acidity could significantly promote the activation of Br- and the production of Br2. The estimated gaseous Br2 production rate under light conditions was up to 1.55×1010 molecules·cm-2·s-1 under light and acidic conditions; these results showed a significant contribution to the atmospheric reactive bromine budget. The reactive oxygen species (ROS) generated during Br- activation could promote the multiphase oxidation of SO2 to produce sulfuric acid, while the increase in acidity had a positive feedback effect on Br- activation. Our findings highlight the crucial role of the proton-electron transfer process in Br2 production.

2.
Phytochemistry ; 226: 114206, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38972440

RESUMO

Eighteen compounds including eleven previously undescribed diterpenes were isolated from the leaves of Croton mangelong. The structures were determined by HRESIMS, IR, NMR, X-ray diffraction and ECD spectroscopic analysis. All isolates were assayed for their anti-hyperglycemic activities in insulin resistance (IR) 3T3-L1 adipocytes, and compound 4 was tested for its anti-diabetic activity in vivo. Results suggested compound 4 could effectively reduce blood glucose level in diabetic SD rats in a dose of 30 mg/kg.

3.
Cell Signal ; : 111301, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019338

RESUMO

Ischemic stroke is one of the most disabling and fatal diseases around the world. The damaged brain tissues will undergo excessive autophagy, vascular endothelial cells injury, blood-brain barrier (BBB) impairment and neuroinflammation after ischemic stroke. However, there is no unified viewpoint on the underlying mechanism of brain damage. Transforming growth factor-ß1 (TGF-ß1), as a multi-functional cytokine, plays a crucial role in the intricate pathological processes and helps maintain the physiological homeostasis of brain tissues through various signaling pathways after ischemic stroke. In this review, we summarize the protective role of TGF-ß1 in autophagic flux, BBB, vascular remodeling, neuroinflammation and other aspects after ischemic stroke. Based on the review, we believe that TGF-ß1 could serve as a key target for treating ischemic stroke.

4.
Cytotherapy ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-39033444

RESUMO

BACKGROUND AIMS: Hu8F4 is a T-cell receptor-like antibody with high affinity for the leukemia-associated antigen PR1/HLA-A2 epitope. Adapted into a chimeric antigen receptor (CAR) format, Hu8F4-CAR is composed of the Hu8F4 single-chain variable fragment, the human IgG1 CH2CH3 extracellular spacer domain, a human CD28 costimulatory domain and the human CD3ζ signaling domain. We have demonstrated high efficacy of Hu8F4-CAR-T cells against PR1/HLA-A2-expressing cell lines and leukemic blasts from patients with acute myeloid leukemia in vitro. Previous studies have shown that modification of the Fc domains of IgG4 CH2CH3 spacer regions can eliminate activation-induced cell death and off-target killing mediated by mouse Fc gamma receptor-expressing cells. METHODS: We generated Hu8F4-CAR(PQ) with mutated Fc receptor binding sites on the CH2 domain of Hu8F4-CAR to prevent unwanted interactions with Fc gamma receptor-expressing cells in vivo. RESULTS: The primary human T cells transduced with Hu8F4-CAR(PQ) can specifically lyse HLA-A2+ PR1-expressing leukemia cell lines in vitro. Furthermore, both adult donor-derived and cord blood-derived Hu8F4-CAR(PQ)-T cells are active and can eliminate U937 leukemia cells in NSG mice. CONCLUSIONS: Herein, we demonstrate that modification of the IgG1-based spacer can eliminate Fc receptor binding-induced adverse effects and Hu8F4-CAR(PQ)-T cells can kill leukemia in vivo.

5.
Artigo em Inglês | MEDLINE | ID: mdl-39034437

RESUMO

Family caregivers living with patients with dementia (PwD) face psychological challenges due to care burden. Technology-delivered psychosocial interventions (TPIs) have played a promising role in improving health outcomes among family caregivers living with PwD. This review aims to synthesise evidence of the effectiveness of TPIs on primary (burden and depression) and secondary outcomes (self-efficacy, stress and anxiety) for family caregivers living with PwD. Random-effects meta-analyses were performed to determine effect size. Using Cochran's Q and I2 tests, statistical heterogeneity was evaluated. Sensitivity, subgroup analyses and meta-regression were employed to explain statistical heterogeneity. Twenty-eight trials comprising 4160 family caregivers from eight countries were included. Our meta-analysis revealed that TPIs resulted in slight reduction in depression, probably resulted in a slight reduction in burden and anxiety and slight increase in self-efficacy. Subgroup differences were detected in geographical regions (Western Pacific and Southeast Asia) for burden. While there were no significant subgroup differences in other factors, TPIs with preventive function and mobile applications had a more prominent larger effect size. Meta-regression analysis showed that attrition rate was a significant moderator on depression. Results are limited by the high risk of bias of included trials, which may reduce certainty of evidence. This review suggest TPIs are recommended as an adjunct treatment for alleviating burden and depressive outcomes in healthcare institutions. PROSPERO Registration Number: PROSPERO (CRD42023387962).

6.
BMJ Open ; 14(7): e078461, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-39019626

RESUMO

OBJECTIVES: To assess the impact of a patient-based self-assessed fatigue intervention aimed at promoting early postoperative ambulation. DESIGN: Prospective randomised controlled trial. SETTING: Single-centre, conducted at the Obstetrics and Gynaecology Department of the Xiangyang Central Hospital, China. PARTICIPANTS: Eligible were adult patients undergoing elective gynaecologic oncologic surgery. INTERVENTIONS: The intervention group utilised a modified Borg Rating of Perceived Experience (RPE) scale for self-assessment of fatigue levels. The control group followed fixed-activity distance guidelines postoperatively. PRIMARY AND SECONDARY OUTCOME MEASURES: The primary outcome was the self-reported the time to first flatus postoperatively. Secondary outcomes encompassed the time to first defecation, incidence of moderate-to-severe abdominal distention, ileus, postambulation adverse events (nausea, vomiting and dizziness), patient satisfaction with early ambulation instructions, compliance with early ambulation and average hospital costs and length of stay. RESULTS: Between June 2021 and October 2022, 552 patients were enrolled. The self-assessed fatigue intervention group demonstrated non-inferior the time to first flatus compared with the fixed-activity distance assessment group (25.59±14.59 hours vs 26.10±14.19 hours, pnon-inferiority<0.001). Compliance with activity was higher in the intervention group (49.40% vs 36.02%, p<0.001), although it did not reach 50%. The intervention group also exhibited significantly higher mean hospital costs, length of stay and incidence of moderate-to-severe abdominal distention (p<0.001). CONCLUSIONS: The self-assessed fatigue intervention for early postoperative ambulation in gynaecologic oncology patients shows promise as an effective strategy; however, compliance is suboptimal. An intervention based on mandatory, yet reasonable, fixed-activity distance may represent the most viable current approach. Further research is warranted to confirm these findings. TRIAL REGISTRATION NUMBER: CTR2100046035.


Assuntos
Deambulação Precoce , Fadiga , Neoplasias dos Genitais Femininos , Procedimentos Cirúrgicos em Ginecologia , Complicações Pós-Operatórias , Humanos , Feminino , Fadiga/etiologia , Pessoa de Meia-Idade , Neoplasias dos Genitais Femininos/cirurgia , Estudos Prospectivos , Adulto , Idoso , Satisfação do Paciente , China , Autoavaliação (Psicologia)
7.
BMJ Open ; 14(6): e084703, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38950988

RESUMO

INTRODUCTION: Orthodontic treatment using face mask protraction combined with an alternate rapid maxillary expansion and constriction/protraction face mask (Alt-RAMEC/PFM) protocol is effective in the early treatment of patients with class III malocclusion, but the stability of treatment outcomes represents a major concern. Previous studies have suggested that tonsillar hypertrophy can be a risk factor for class III malocclusion and tonsillectomy may prompt the normalisation of dentofacial growth. However, these studies had a low-to-moderate level of evidence. This study was designed to identify the impact of tonsillectomy before orthodontic treatment on the efficacy and stability of Alt-RAMEC/PFM protocols and the sleep quality and oral health in children with anterior crossbite and tonsillar hypertrophy. METHODS AND ANALYSIS: This is a two-arm, parallel-group, superiority cluster randomised controlled trial, with four clinics randomly assigned to the surgery-first arm and the orthodontic-first arm in a 1:1 ratio. The Alt-RAMEC protocol involves alternate activation and deactivation of the expander's jet screw over 6 weeks to stimulate maxillary suture distraction. Patients will be instructed to wear the PFM for a minimum of 14 hours per day. The primary outcomes are changes in Wits appraisal and the degree of maxillary advancement from baseline to the end of orthodontic treatment. Lateral cephalometric radiographs, polysomnography, Obstructive Sleep Apnoea-18 questionnaire and Oral Health Impact Profile-14 questionnaire will be traced, collected and measured. We will recruit 96 patients intofor the study. To assess differences, repeated multilevel linear mixed modelling analyses will be used. ETHICS AND DISSEMINATION: This study has been granted ethical approval by the Ethics Committee of the School & Hospital of Stomatology, Wuhan University (approval No. 2023-D10). Written informed consent will be obtained from the participants and their guardians. The results of the trial will be disseminated through academic conferences and journal publications. TRIAL REGISTRATION NUMBER: ChiCTR2300078833.


Assuntos
Hipertrofia , Má Oclusão Classe III de Angle , Técnica de Expansão Palatina , Tonsila Palatina , Tonsilectomia , Humanos , Tonsilectomia/métodos , Criança , Má Oclusão Classe III de Angle/cirurgia , Má Oclusão Classe III de Angle/terapia , Tonsila Palatina/patologia , Tonsila Palatina/cirurgia , Feminino , Aparelhos de Tração Extrabucal , Ensaios Clínicos Controlados Aleatórios como Assunto , Masculino , Resultado do Tratamento , Qualidade do Sono , Adolescente
8.
Chem Soc Rev ; 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39007174

RESUMO

Nitrous oxide (N2O) decomposition is increasingly acknowledged as a viable strategy for mitigating greenhouse gas emissions and addressing ozone depletion, aligning significantly with the UN's sustainable development goals (SDGs) and carbon neutrality objectives. To enhance efficiency in treatment and explore potential valorization, recent developments have introduced novel N2O reduction catalysts and pathways. Despite these advancements, a comprehensive and comparative review is absent. In this review, we undertake a thorough evaluation of N2O treatment technologies from a holistic perspective. First, we summarize and update the recent progress in thermal decomposition, direct catalytic decomposition (deN2O), and selective catalytic reduction of N2O. The scope extends to the catalytic activity of emerging catalysts, including nanostructured materials and single-atom catalysts. Furthermore, we present a detailed account of the mechanisms and applications of room-temperature techniques characterized by low energy consumption and sustainable merits, including photocatalytic and electrocatalytic N2O reduction. This article also underscores the extensive and effective utilization of N2O resources in chemical synthesis scenarios, providing potential avenues for future resource reuse. This review provides an accessible theoretical foundation and a panoramic vision for practical N2O emission controls.

9.
Front Neurol ; 15: 1375587, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39036634

RESUMO

Background: Many systematic reviews (SRs) and meta-analysis (MAs) have reported the efficacy of acupuncture treatment for primary trigeminal neuralgia (PTN), but the quality of evidence is unknown and therefore needs to be evaluated comprehensively. Methods: Eight electronic databases were searched from their inception until January 5, 2024. The methodological quality, reporting quality, and risk of bias of the included SRs were assessed by the assessment of multiple systematic reviews 2 (AMSTAR-2), the Risk of Bias in Systematic Reviews (ROBIS) tool, and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). The quality of evidence for outcome measures was evaluated using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE). Results: We identified 13 SRs/MAs met inclusion criteria. According to the results of the AMSTAR-2, six were rated as critically low quality and seven as low quality. According to ROBIS assessment, 8 SRs/MAs were classified as low risk, and 5 SRs/MAs were found to be high risk. The PRISMA report still has some reporting deficiencies in aspects such as protocol and registration, search strategy, risk of bias, additional analyzes and funding. According to the GRADE system, no high-quality evidence was found, 1 was of moderate quality, 4 were of low quality, and 8 were of critical low quality. Conclusion: Based on the evidence collected, acupuncture shows promise as a treatment for PTN patients. However, it is important to note that the included SRs/MAs generally have low methodological quality and evidence quality. Therefore, caution must be exercised when interpreting this conclusion. To enhance future research in this area, it is recommended to adequately report methodological details and adhere to guidelines for conducting SRs/MAs.Systematic review registration: https://www.crd.york.ac.uk/prospero/, identifier CRD42024499280.

10.
Int J Biol Macromol ; 272(Pt 1): 132843, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38830489

RESUMO

The study aimed to inhibit the stimulating impact of garlic oil (GO) on the stomach and attain high release in the intestine during digestion. So, wheat porous starch (WPS) was modified with octenyl succinic acid (OSA) and malic acid (MA) to obtain esterified WPS, OWPS and MWPS, respectively. The differences in physicochemical, encapsulation, and digestive properties of two GO microcapsules, WPI/OWPS/GO and WPI/MWPS/GO microcapsules produced by using OWPS and MWPS as variant carrier materials and whey protein isolate (WPI) as the same coating agent, were compared. The results found that OWPS had greater amphiphilicity, while MWPS had better hydrophobicity and anti-digestive ability than WPS. Encapsulation efficiency of WPI/OWPS/GO (94.67 %) was significantly greater than WPI/MWPS/GO (91.44 %). The digestion inhibition and low GO release (approximately 23 %) of WPI/OWPS/GO and WPI/MWPS/GO microcapsules in the gastric phase resulted from the protective effect of WPI combined with the good adsorption and lipophilicity of OWPS and MWPS. Especially, WPI/OWPS/GO microcapsule was relatively stable in the gastric phase and had sufficient GO release (67.24 %) in the intestinal phase, which was significantly higher than WPI/MWPS/GO microcapsule (56.03 %), benefiting from the adsorption and digestive properties of OWPS, and resulting in a total cumulative GO release rate of 90.86 %.


Assuntos
Digestão , Amido , Triticum , Proteínas do Soro do Leite , Proteínas do Soro do Leite/química , Amido/química , Triticum/química , Porosidade , Cápsulas , Fenômenos Químicos , Óleos de Plantas/química , Interações Hidrofóbicas e Hidrofílicas , Composição de Medicamentos , Alho/química
11.
Midwifery ; 136: 104068, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38909554

RESUMO

AIMS: To explore the underlying beliefs of preventive health behaviours among women with a history of GDM who had low levels of preventive health behaviours during their postpartum period in Singapore. METHODS: This paper reports on the qualitative arm of a mixed method study. The qualitative descriptive design was adopted. Individual interviews were conducted between 7th September 2020 and 25th September 2020 using a semi-structured interview guide. Data collected were analysed using thematic analysis. RESULTS: A total of 18 women completed the interview. The participants' ages ranged from 26 to 40 years with a mean age of 33.17 years (SD= 4.09). The duration since childbirth was 8.78 months (SD = 1.35). Through thematic analysis, five themes were developed: lifestyle adjustment, self-motivation, supportive environment, barriers to practising a healthy lifestyle, and risk perception. A total of 14 subthemes emerged from the five main themes. The beliefs of women with a history of GDM were described according to the Theory of Planned Behaviour. CONCLUSIONS: Having a newborn brings changes to the lifestyle of a woman and her family, which can affect the health behaviours in the postpartum period. This study revealed several novel findings relating to the unmet needs of women who had GDM, specifically to the need for information and emotional support to safely resume healthy behaviours after childbirth, for which participants have provided suggestions on how to enhance the continuity of care in the postpartum period.

12.
Front Zool ; 21(1): 15, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38863001

RESUMO

The most extraordinary systems of symbiosis in insects are found in the suborder Auchenorrhyncha of Hemiptera, which provide unique perspectives for uncovering complicated insect-microbe symbiosis. We investigated symbionts associated with bacteriomes and fat bodies in six cicada species, and compared transmitted cell number ratio of related symbionts in ovaries among species. We reveal that Sulcia and Hodgkinia or a yeast-like fungal symbiont (YLS) are segregated from other host tissues by the bacteriomes in the nymphal stage, then some of them may migrate to other organs (i.e., fat bodies and ovaries) during host development. Particularly, YLS resides together with Sulcia in the "symbiont ball" of each egg and the bacteriomes of young-instar nymphs, but finally migrates to the fat bodies of adults in the majority of Hodgkinia-free cicadas, whereas it resides in both bacteriome sheath and fat bodies of adults in a few other species. The transmitted Sulcia/YLS or Sulcia/Hodgkinia cell number ratio in ovaries varies significantly among species, which could be related to the distribution and/or lineage splitting of symbiont(s). Rickettsia localizes to the nuclei of bacteriomes and fat bodies in some species, but it was not observed to be transmitted to the ovaries, indicating that this symbiont may be acquired from environments or from father to offspring. The considerable difference in the transovarial transmission process of symbionts suggests that cellular mechanisms underlying the symbiont transmission are complex. Our results may provide novel insights into insect-microbe symbiosis.

13.
Digit Health ; 10: 20552076241256861, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832099

RESUMO

Objective: Stroke survivors often experience residual impairments and motor decline post-discharge. While digital home rehabilitation combined with supervision could be a promising approach for reducing human resources, increasing motor ability, and supporting rehabilitation persistence there is a lack of reviews synthesizing the effects. Thus, this systematic review and meta-analysis aimed to synthesize the effect of digital home rehabilitation and supervision in improving motor ability of upper limb, static balance, stroke-related quality of life, and self-reported arm function among stroke survivors. Methods: Six electronic databases, grey literature, ongoing studies, and reference lists were searched for relevant studies. Two investigators independently reviewed titles, abstracts, screened full texts for eligibility and performed data extraction. Meta-analysis of 13 independent studies were grouped into four separate meta-analyses. The Grading of Recommendations, Assessments, Development and Evaluations (GRADE) tool was used for evaluating the overall quality of the evidence. Results: Meta-analyses showed no statistically significant difference between intervention (digital home rehabilitation) and control groups (home training/clinic-based) of all outcomes including motor ability of upper limb, static balance, stroke-related quality of life, and self-reported arm function. In the sub-group analysis digital home rehabilitation was associated with better quality of arm use (standardized mean difference = 0.68, 95% confidence interval: [0.27, 1.09], p = 0.001). Conclusions: This result indicated that digital home rehabilitation has similar effects and could potentially replace home training or clinic-based services. This review highlights better-targeted digital motor interventions to examine the effects of interventions further. The quality of evidence was moderate to high in motor and self-reported arm outcomes, and low for balance and quality of life.

14.
Environ Sci Technol ; 58(23): 10175-10184, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38771930

RESUMO

The interplay between sulfur and iron holds significant importance in their atmospheric cycle, yet a complete understanding of their coupling mechanism remains elusive. This investigation delves comprehensively into the evolution of reactive oxygen species (ROS) during the interfacial reactions involving sulfur dioxide (SO2) and iron oxides under varying relative humidity conditions. Notably, the direct activation of water by iron oxide was observed to generate a surface hydroxyl radical (•OH). In comparison, the aging of SO2 was found to markedly augment the production of •OH radicals on the surface of α-Fe2O3 under humid conditions. This augmentation was ascribed to the generation of superoxide radicals (•O2-) stemming from the activation of O2 through the Fe(II)/Fe(III) cycle and its combination with the H+ ion to produce hydrogen peroxide (H2O2) on the acidic surface. Moreover, the identification of moderate relative humidity as a pivotal factor in sustaining the surface acidity of iron oxide during SO2 aging underscores its crucial role in the coupling of iron dissolution, ROS production, and SO2 oxidation. Consequently, the interfacial reactions between SO2 and iron oxides under humid conditions are elucidated as atmospheric processes that enhance oxidation capacity rather than deplete ROS. These revelations offer novel insights into the mechanisms underlying •OH radical generation and oxidative potential within atmospheric interfacial chemistry.


Assuntos
Espécies Reativas de Oxigênio , Dióxido de Enxofre , Dióxido de Enxofre/química , Compostos Férricos/química , Radical Hidroxila/química , Oxirredução , Peróxido de Hidrogênio/química , Umidade
15.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167236, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38740225

RESUMO

Pancreatic ductal adenocarcinoma (PDA) is a common malignancy with a 5-year survival <10 %. Immunosuppressive tumor microenvironment (TME) plays a critical role in the progression of PDA. In recent years, programmed death-ligand 1 (PD-L1)/programmed cell death protein-1 (PD-1) blockade has emerged as a potent anti-tumor immunotherapy, while is yet to achieve significant clinical benefits for PDA patients. P21-Activated kinase 1 (PAK1) is highly upregulated in PDA and has been reported to be involved in the regulation of anti-tumor immunity. This study aims to investigate the combined effect of PAK1 inhibition and anti-PD-1 therapy on PDA and the underlying mechanisms. We have shown that PAK1 expression positively correlated with PD-L1 in PDA patients, and that inhibition of PAK1 downregulated PD-L1 expression of PDA cells. More importantly, we have demonstrated that PAK1 competed with PD-L1 in binding to tripartite motif-containing protein 21 (TRIM21), a ubiquitin E3 ligase, resulting in less ubiquitination and degradation of PD-L1. Moreover, PAK1 inhibition promoted CD8+ T cells activation and infiltration. In a murine PDA model, the combination of PAK1 inhibition and anti-PD-1 therapy showed significant anti-tumor effects compared with the control or monotherapy. Our results indicated that the combination of PAK1 inhibition and anti-PD-1 therapy would be a more effective treatment for PDA patients.


Assuntos
Antígeno B7-H1 , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Quinases Ativadas por p21 , Quinases Ativadas por p21/metabolismo , Quinases Ativadas por p21/antagonistas & inibidores , Quinases Ativadas por p21/genética , Humanos , Animais , Neoplasias Pancreáticas/tratamento farmacológico , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas/imunologia , Antígeno B7-H1/metabolismo , Antígeno B7-H1/antagonistas & inibidores , Camundongos , Carcinoma Ductal Pancreático/tratamento farmacológico , Carcinoma Ductal Pancreático/patologia , Carcinoma Ductal Pancreático/metabolismo , Carcinoma Ductal Pancreático/imunologia , Linhagem Celular Tumoral , Feminino , Masculino , Inibidores de Checkpoint Imunológico/farmacologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Receptor de Morte Celular Programada 1/antagonistas & inibidores , Receptor de Morte Celular Programada 1/metabolismo , Proteólise/efeitos dos fármacos , Microambiente Tumoral/efeitos dos fármacos , Microambiente Tumoral/imunologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/efeitos dos fármacos , Ubiquitinação/efeitos dos fármacos , Camundongos Endogâmicos C57BL
16.
J Org Chem ; 89(11): 7531-7540, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38761155

RESUMO

An organocatalyzed photoelectrochemical method for the generation of acyl and phosphoryl radicals from formamides, aldehydes, and phosphine oxides has been developed. This protocol utilizes 9,10-phenanthrenequinone (PQ) as both a molecular catalyst and a hydrogen atom-transfer (HAT) reagent, eliminating the requirement for external metal-based reagents, HAT reagents, and oxidants. The generated acyl radicals can be applied to a range of radical-mediated transformation reactions, including C-H carbamoylation of heteroarenes, intermolecular tandem radical cyclization of CF3-substituted N-arylacrylamides, as well as intramolecular cyclization reactions. The use of acyl radicals in these transformations offers an efficient and sustainable approach to accessing structurally diverse carbonyl compounds.

17.
Tree Physiol ; 44(6)2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38769900

RESUMO

The effects of rising atmospheric CO2 concentrations (Ca) with climate warming on intrinsic water-use efficiency and radial growth in boreal forests are still poorly understood. We measured tree-ring cellulose δ13C, δ18O, and tree-ring width in Larix dahurica (larch) and Betula platyphylla (white birch), and analyzed their relationships with climate variables in a boreal permafrost region of northeast China over past 68 years covering a pre-warming period (1951-1984; base period) and a warm period (1985-2018; warm period). We found that white birch but not larch significantly increased their radial growth over the warm period. The increased intrinsic water-use efficiency in both species was mainly driven by elevated Ca but not climate warming. White birch but not larch showed significantly positive correlations between tree-ring δ13C, δ18O and summer maximum temperature as well as vapor pressure deficit in the warm period, suggesting a strong stomatal response in the broad-leaved birch to temperature changes. The climate warming-induced radial growth enhancement in white birch is primarily associated with a conservative water-use strategy. In contrast, larch exhibits a profligate water-use strategy. It implies an advantage for white birch over larch in the warming permafrost regions.


Assuntos
Betula , Larix , Pergelissolo , Água , Larix/crescimento & desenvolvimento , Larix/fisiologia , Betula/crescimento & desenvolvimento , Betula/fisiologia , Água/metabolismo , China , Mudança Climática , Taiga , Aquecimento Global
18.
J Nurs Scholarsh ; 56(4): 563-584, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38703352

RESUMO

INTRODUCTION: Nurses, assuming a wide range of clinical and patient care responsibilities in a healthcare team, are highly susceptible to direct and indirect exposure to traumatic experiences. However, literature has shown that nurses with certain traits developed a new sense of personal strength in the face of adversity, known as post-traumatic growth (PTG). This review aimed to synthesize the best available evidence to evaluate personal and work-related factors associated with PTG among nurses. DESIGN: Mixed studies systematic review. METHODS: Studies examining factors influencing PTG on certified nurses from all healthcare facilities were included. Published and unpublished studies were identified by searching 12 databases from their inception until 4th February 2023. Two reviewers independently screened, appraised, piloted a data collection form, and extracted relevant data. Meta-summary, meta-synthesis, meta-analysis, as well as subgroup and sensitivity analyses were performed. Integration of results followed result-based convergent design. RESULTS: A total of 98 studies with 29,706 nurses from 18 countries were included. These included 49 quantitative, 42 qualitative, and seven mixed-methods studies. Forty-six influencing factors were meta-analyzed, whereas nine facilitating factors were meta-summarized. A PTG conceptual map was created. Four constructs emerged from the integration synthesis: (a) personal system, (b) work-related system, (c) event-related factors, and (d) cognitive transformation. CONCLUSION: The review findings highlighted areas healthcare organizations could do to facilitate PTG in nurses. Practical implications include developing intervention programs based on PTG facilitators. Further research should examine the trend of PTG and its dynamic response to different nursing factors. CLINICAL RELEVANCE: Research on trauma-focused therapies targeting nurses' mental health is lacking. Therefore, findings from this review could inform healthcare organizations on the PTG phenomenon and developing support measures for nurses through healthcare policies and clinical practice.


Assuntos
Crescimento Psicológico Pós-Traumático , Humanos , Enfermeiras e Enfermeiros/psicologia , Local de Trabalho/psicologia
19.
Environ Sci Technol ; 58(23): 10357-10367, 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38728016

RESUMO

The urgent environmental concern of methane abatement, attributed to its high global warming potential, necessitates the development of methane oxidation catalysts (MOC) with enhanced low-temperature activity and durability. Herein, an iridium-doped PdOx nanoparticle supported on silicalite-1 zeolite (PdIr/S-1) catalyst was synthesized and applied for methane catalytic combustion. Comprehensive characterizations confirmed the atomically dispersed nature of iridium on the surface of PdOx nanoparticles, creating an Ir4f-O-Pdcus microstructure. The atomically doped Ir transferred more electrons to adjacent oxygen atoms, modifying the electronic structure of PdOx and thus enhancing the redox ability of the PdIr/S-1 catalysts. This electronic modulation facilitated methane adsorption on the Pd site of Ir4f-O-Pdcus, reducing the energy barrier for C-H bond cleavage and thereby increasing the reaction rate for methane oxidation. Consequently, the optimized PdIr0.1/S-1 showed outstanding low-temperature activity for methane combustion (T50 = 276 °C) after aging and maintained long-term stability over 100 h under simulated exhaust conditions. Remarkably, the novel PdIr0.1/S-1 catalyst demonstrated significantly enhanced activity even after undergoing harsh hydrothermal aging at 750 °C for 16 h, significantly outperforming the conventional Pd/Al2O3 catalyst. This work provides valuable insights for designing efficient and durable MOC catalysts, addressing the critical issue of methane abatement.


Assuntos
Irídio , Metano , Nanopartículas , Oxirredução , Metano/química , Irídio/química , Catálise , Nanopartículas/química , Zeolitas/química , Paládio/química
20.
Nat Commun ; 15(1): 3874, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38719826

RESUMO

The "terminal hydroxyl group anchoring mechanism" has been studied on metal oxides (Al2O3, CeO2) as well as a variety of noble and transition metals (Ag, Pt, Pd, Cu, Ni, Fe, Mn, and Co) in a number of generalized studies, but there is still a gap in how to regulate the content of terminal hydroxyl groups to influence the dispersion of the active species and thus to achieve optimal catalytic performance. Herein, we utilized AlOOH as a precursor for γ-Al2O3 and induced the transformation of the exposed crystal face of γ-Al2O3 from (110) to (100) by controlling the calcination temperature to generate more terminal hydroxyl groups to anchor Ag species. Experimental results combined with AIMD and DFT show that temperature can drive the atomic rearrangement on the (110) crystal face, thereby forming a structure similar to the atomic arrangement of the (100) crystal face. This resulted in the formation of more terminal hydroxyl groups during the high-temperature calcination of the support (Al-900), which can capture Ag species to form single-atom dispersions, and ultimately develop a stable and efficient single-atom Ag-based catalyst.

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