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1.
Chem Soc Rev ; 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-39007174

ABSTRACT

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.

2.
BMJ Open ; 14(6): e084703, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38950988

ABSTRACT

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.


Subject(s)
Hypertrophy , Malocclusion, Angle Class III , Palatal Expansion Technique , Palatine Tonsil , Tonsillectomy , Humans , Tonsillectomy/methods , Child , Malocclusion, Angle Class III/surgery , Malocclusion, Angle Class III/therapy , Palatine Tonsil/pathology , Palatine Tonsil/surgery , Female , Extraoral Traction Appliances , Randomized Controlled Trials as Topic , Male , Treatment Outcome , Sleep Quality , Adolescent
3.
Phytochemistry ; 226: 114206, 2024 Jul 05.
Article in English | MEDLINE | ID: mdl-38972440

ABSTRACT

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.

4.
Angew Chem Int Ed Engl ; : e202409779, 2024 Jul 11.
Article in English | MEDLINE | ID: mdl-38989722

ABSTRACT

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.

5.
Front Zool ; 21(1): 15, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38863001

ABSTRACT

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.

6.
Int J Biol Macromol ; 272(Pt 1): 132843, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38830489

ABSTRACT

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 %.


Subject(s)
Digestion , Starch , Triticum , Whey Proteins , Whey Proteins/chemistry , Starch/chemistry , Triticum/chemistry , Porosity , Capsules , Chemical Phenomena , Plant Oils/chemistry , Hydrophobic and Hydrophilic Interactions , Drug Compounding , Garlic/chemistry
7.
Digit Health ; 10: 20552076241256861, 2024.
Article in English | MEDLINE | ID: mdl-38832099

ABSTRACT

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.

8.
Midwifery ; 136: 104068, 2024 Jun 15.
Article in English | MEDLINE | ID: mdl-38909554

ABSTRACT

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.

9.
Heliyon ; 10(9): e30014, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38699009

ABSTRACT

Electroacupuncture (EA) is a neuroregulatory therapy for depression. Nonetheless, the effects of EA on the gut microbiome in mice models of depression are not well established. Here, using a chronic unpredictable mild stress (CUMS) model in mice, we evaluated the antidepressant effects of EA and changes in gut microbiota with behavioral tests and 16S rRNA gene sequencing. The results found that EA increased the time spent in the center area of the open-field test and the percentage of sucrose preference and reduced the immobility time in the tail suspension test in CUMS-treated mice. Furthermore, the genus Lachnoclostridium, Ruminococcaceae_UCG-002 and Rikenellaceae_RC9_gut_group were enriched in the CUMS group, which was positively correlated with depressive-like behaviors. Whereas phylum Actinobacteria and genus Allobaculum, Bifidobacterium, Dubosiella, Rikenella and Ileibacterium were enriched in the EA and CUMS + EA groups, all of which were negatively correlated with depressive-like behaviors. This study characterizes gut microbiota under EA treatment and provides new insights into the association of anti-depressive-like effects of EA and gut microbiota.

10.
Eur J Orthod ; 46(3)2024 Jun 01.
Article in English | MEDLINE | ID: mdl-38733349

ABSTRACT

OBJECTIVES: The biomechanics in achieving molar distalization may differ between fixed appliances and clear aligners in the control of tooth movement. The objective of this study was to compare the treatment effects between clear aligners (CA) and fixed appliances (FA) in patients treated with miniscrew-assisted molar distalization. METHODS: The sample consisted of 46 subjects with mild-to-moderate crowding. A total of 22 patients treated with clear aligners (age, 25.66 ±â€…6.11 years old) and 24 patients treated with fixed appliances (age, 24.04 ±â€…4.95 years old) for miniscrew-assisted molar distalization were included in this study. The dental and skeletal changes were evaluated by the pre- and post-treatment lateral cephalograms. RESULTS: Significant changes were found with the vertical variables SN-OP angle (2.24 ±â€…3.22°, P < .05) and SN-MP angle (0.73 ±â€…1.15°, P < .05) for the FA group when compared with the CA group (SN-OP angle 0.41 ±â€…2.26° and SN-MP angle -0.21 ±â€…1.38°, P > .05). Both treatment groups achieved a 2-3 mm. molar distalization with significant intrusion of the upper molars. The CA group showed significantly less distal tipping of molars (U6^PP angle -2.29 ±â€…3.29° and L6^MP angle -2.92 ±â€…2.49°, P < .05) compared to the FA group (-5.24 ±â€…4.28° and -5.53 ±â€…5.03°, P < .05). In addition, significant retraction and lingual inclination of the upper and lower incisors were found in both groups. LIMITATIONS: The changes of tooth position were evaluated by 2D lateral cephalograms, not 3D measurements. CONCLUSIONS: Compared to fixed appliances, clear aligners seemed to have better control of vertical dimension and distal tipping of molars in patients treated with miniscrew-assisted molar distalization.


Subject(s)
Bone Screws , Cephalometry , Molar , Orthodontic Anchorage Procedures , Orthodontic Appliances, Fixed , Tooth Movement Techniques , Humans , Tooth Movement Techniques/instrumentation , Tooth Movement Techniques/methods , Male , Female , Adult , Orthodontic Anchorage Procedures/instrumentation , Orthodontic Anchorage Procedures/methods , Young Adult , Orthodontic Appliance Design , Malocclusion/therapy , Treatment Outcome , Maxilla , Mandible , Orthodontic Appliances, Removable , Incisor , Vertical Dimension
11.
Sci China Life Sci ; 2024 May 09.
Article in English | MEDLINE | ID: mdl-38733513

ABSTRACT

Atmospheric vapor pressure deficit (VPD) increases with climate warming and may limit plant growth. However, gross primary production (GPP) responses to VPD remain a mystery, offering a significant source of uncertainty in the estimation of global terrestrial ecosystems carbon dynamics. In this study, in-situ measurements, satellite-derived data, and Earth System Models (ESMs) simulations were analysed to show that the GPP of most ecosystems has a similar threshold in response to VPD: first increasing and then declining. When VPD exceeds these thresholds, atmospheric drought stress reduces soil moisture and stomatal conductance, thereby decreasing the productivity of terrestrial ecosystems. Current ESMs underscore CO2 fertilization effects but predict significant GPP decline in low-latitude ecosystems when VPD exceeds the thresholds. These results emphasize the impacts of climate warming on VPD and propose limitations to future ecosystems productivity caused by increased atmospheric water demand. Incorporating VPD, soil moisture, and canopy conductance interactions into ESMs enhances the prediction of terrestrial ecosystem responses to climate change.

12.
Nat Commun ; 15(1): 3874, 2024 May 08.
Article in English | MEDLINE | ID: mdl-38719826

ABSTRACT

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.

13.
J Nurs Scholarsh ; 56(4): 563-584, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38703352

ABSTRACT

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.


Subject(s)
Posttraumatic Growth, Psychological , Humans , Nurses/psychology , Workplace/psychology
14.
Biochim Biophys Acta Mol Basis Dis ; 1870(6): 167236, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38740225

ABSTRACT

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.


Subject(s)
B7-H1 Antigen , Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , p21-Activated Kinases , p21-Activated Kinases/metabolism , p21-Activated Kinases/antagonists & inhibitors , p21-Activated Kinases/genetics , Humans , Animals , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/metabolism , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/immunology , B7-H1 Antigen/metabolism , B7-H1 Antigen/antagonists & inhibitors , Mice , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/metabolism , Carcinoma, Pancreatic Ductal/immunology , Cell Line, Tumor , Female , Male , Immune Checkpoint Inhibitors/pharmacology , Immune Checkpoint Inhibitors/therapeutic use , Programmed Cell Death 1 Receptor/antagonists & inhibitors , Programmed Cell Death 1 Receptor/metabolism , Proteolysis/drug effects , Tumor Microenvironment/drug effects , Tumor Microenvironment/immunology , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , CD8-Positive T-Lymphocytes/drug effects , Ubiquitination/drug effects , Mice, Inbred C57BL
15.
J Org Chem ; 89(11): 7531-7540, 2024 Jun 07.
Article in English | MEDLINE | ID: mdl-38761155

ABSTRACT

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.

16.
Environ Sci Technol ; 58(23): 10357-10367, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38728016

ABSTRACT

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.


Subject(s)
Iridium , Methane , Nanoparticles , Oxidation-Reduction , Methane/chemistry , Iridium/chemistry , Catalysis , Nanoparticles/chemistry , Zeolites/chemistry , Palladium/chemistry
17.
Environ Sci Technol ; 58(23): 10175-10184, 2024 Jun 11.
Article in English | MEDLINE | ID: mdl-38771930

ABSTRACT

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.


Subject(s)
Reactive Oxygen Species , Sulfur Dioxide , Sulfur Dioxide/chemistry , Ferric Compounds/chemistry , Hydroxyl Radical/chemistry , Oxidation-Reduction , Hydrogen Peroxide/chemistry , Humidity
18.
Nat Prod Res ; : 1-7, 2024 May 24.
Article in English | MEDLINE | ID: mdl-38785383

ABSTRACT

Preliminary pharmacological studies revealed that the EtOAc fraction (BGEA) might be the main active fraction with anti-inflammatory and antinociceptive effects in Beaumontia grandiflora Wall. Further assays on BGEA at doses of 200, 400, and 800 mg/kg using four animal models showed that it could inhibit the xylene-induced ear edema, carrageenan-induced paw edema, and acetic acid-induced writhing and prolong the latency time in the hot-plate test. ELISA analysis revealed that the anti-inflammatory activity of BGEA might be associated with the decrease of TNF-α, IL-1ß, and IL-6 levels and the increase of the IL-10 level. The acute toxicity test showed that except for the n-BuOH fraction, the LD50 values of the extract and other three fractions were higher than 2000 mg/kg bw. Finally, 14 compounds were identified from BGEA by LC-MS. This research provides some basis for the folk use of B. grandiflora in the treatment of inflammation and pain-related diseases.

19.
Cell Commun Signal ; 22(1): 287, 2024 May 27.
Article in English | MEDLINE | ID: mdl-38797819

ABSTRACT

BACKGROUND: Pancreatic ductal adenocarcinoma (PDA) is one of the most lethal types of cancer, and KRAS oncogene occurs in over 90% of cases. P21-activated kinases (PAK), containing six members (PAK1 to 6), function downstream of KRAS. PAK1 and PAK4 play important roles in carcinogenesis, but their combinational effect remains unknown. In this study, we have determined the effect of dual inhibition of PAK1 and PAK4 in PDA progression using knockout (KO) cancer cell lines. METHODS: Murine wild-type (WT) and PAK1KO pancreatic cancer cell lines were isolated from PAK1+/+ and PAK1-/- KPC (LSL-KrasG12D/+; LSL-Trp53 R172H/+; Pdx-1-Cre) mice. KPC PAK4KO and KPC PAK1&4 KO cell lines were generated from KPC WT and KPC PAK1KO cell lines respectively using the CRISPR-CAS9 gene knockout technique. PAK WT and KO cell lines were used in mouse models of pancreatic tumours. Cells and tumour tissue were also used in flow cytometry and proteomic studies. A human PDA tissue microarray was stained by immunohistochemistry. RESULTS: Double knock out of PAK1 and PAK4 caused complete regression of tumour in a syngeneic mouse model. PAK4KO inhibited tumour growth by stimulating a rapid increase of cytotoxic CD8+ T cell infiltration. PAK1KO synergistically with PAK4KO increased cytotoxic CD8+ T cell infiltration and stimulated a sustained infiltration of CD8+ T cells at a later phase to overcome the immune evasion in the PAK4KO tumour. The human PDA tissue microarray study showed the important role of PAK1 and PAK4 in intra-tumoral T-cell function. CONCLUSION: Our results demonstrated that dual inhibition of PAK1 and PAK4 synergistically suppressed PDA progression by stimulating cytotoxic CD8 + T cell response.


Subject(s)
Pancreatic Neoplasms , p21-Activated Kinases , p21-Activated Kinases/metabolism , p21-Activated Kinases/genetics , p21-Activated Kinases/antagonists & inhibitors , Animals , Pancreatic Neoplasms/pathology , Pancreatic Neoplasms/immunology , Pancreatic Neoplasms/genetics , Mice , Cell Line, Tumor , Humans , Cell Proliferation , Carcinoma, Pancreatic Ductal/pathology , Carcinoma, Pancreatic Ductal/immunology , Carcinoma, Pancreatic Ductal/genetics , Mice, Knockout
20.
Environ Sci Technol ; 58(21): 9381-9392, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38747138

ABSTRACT

Designing suitable catalysts for efficiently degrading volatile organic compounds (VOCs) is a great challenge due to the distinct variety and nature of VOCs. Herein, the suitability of different typical VOCs (toluene and acetone) over Pt-based catalysts and Mn2O3 was investigated carefully. The activity of Mn2O3 was inferior to Pt-loaded catalysts in toluene oxidation but showed superior ability for destroying acetone, while Pt loading could boost the catalytic activity of Mn2O3 for both acetone and toluene. This suitability could be determined by the physicochemical properties of the catalysts and the structure of the VOC since toluene destruction activity is highly reliant on Pt0 in the metallic state and linearly correlated with the amount of surface reactive oxygen species (Oads), while the crucial factor that affects acetone oxidation is the mobility of lattice oxygen (Olat). The Pt/Mn2O3 catalyst shows highly active Pt-O-Mn interfacial sites, favoring the generation of Oads and promoting Mn-Olat mobility, leading to its excellent performance. Therefore, the design of abundant active sites is an effective means of developing highly adaptive catalysts for the oxidation of different VOCs.


Subject(s)
Oxidation-Reduction , Platinum , Volatile Organic Compounds , Volatile Organic Compounds/chemistry , Catalysis , Platinum/chemistry , Oxides/chemistry , Manganese Compounds/chemistry
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