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1.
Artigo em Inglês | MEDLINE | ID: mdl-39344047

RESUMO

Recent studies have revealed that the integration of metal nanoparticles (NPs) with photocatalysts allows the metal NPs to serve as cocatalysts, significantly enhancing reactant efficiency near nanostructures through the surface plasmon resonance (SPR) effect. On this basis, we synthesized highly reactive FePt quantum dots (FePt QDs) with tailored configurations, manipulating the Pt coordination environment and combining FePt QDs with ultrathin two-dimensional nickel metal-organic layer (Ni-MOL) nanosheets. X-ray absorption fine spectroscopy (XAFS) confirmed the distinctive Pt-Fe configuration after photoactivation. The optimized loading amount of FePt QDs led to a hydrogen evolution reaction (HER) yield of 113 mmol·g-1·h-1 after activation, with the catalyst remaining stable over five cycles. The improved reaction efficiency stemmed from Pt coordination adjustments and a localized SPR effect, supported by ultraviolet-visible (UV-vis), infrared (IR), Raman, and XAFS characterizations. A comparative analysis was conducted with Ni-MOL deposited with platinum NPs, further underscoring the distinct advantages of FePt QDs and corroborating by density functional theory (DFT) calculations, which revealed favorable d-band center properties. These findings offer a promising avenue for the development of highly efficient and stable nanoalloy photocatalysts.

2.
Artigo em Inglês | MEDLINE | ID: mdl-39264394

RESUMO

BACKGROUND: Catheter ablation has obtained class 1 indication in ablation of young, healthy patients with symptomatic paroxysmal atrial fibrillation (AF). Anti-arrhythmic drugs (AADs) remain first-line therapy before ablating persistent AF (PersAF). We sought to evaluate the efficacy of a direct-to-catheter ablation approach against catheter ablation post AADs in PersAF. METHODS: In this DECAAF II subanalysis, patients were stratified into two subgroups: 'Direct-to-catheter' group comprising patients who had not received AADs prior to ablation, and'second-line ablation' group, comprising patients who had been on any AAD therapy at any time before ablation. Patients were followed over 18 months. The primary outcome was AF recurrence. Secondary outcomes included AF burden, quality of life (QoL) that assessed by the AFSS and SF-36 scores, and changes in the left atrial volume index (LAVI) assessed by LGE-MRI scans. RESULTS: The analysis included 815 patients, with 279 classified as'direct-to-catheter' group and 536 classified as'Second-line ablation' group. The primary outcome was similar between both groups (44.8% vs 44.4%, p > 0.05), as was AF burden (20% vs 16%, p > 0.05). Early remodeling, reflected by LAVI reduction, was similar between the groups (9.1 [1.6-18.0] in the second-line ablation group and 9.5 [2.5-19.7] in the direct-to-catheter group, p > 0.05). QoL pre/post ablation was also similar (p > 0.05). On multivariate analysis, history of AAD was not predictive of AF recurrence(p > 0.05). CONCLUSION: Prior AAD therapy demonstrated minimal impact on atrial remodeling and QoL improvement, in addition to limited benefit on AF recurrence and burden post-ablation in patients with PersAF. Additional studies are warranted to explore the efficacy of catheter ablation as a first-line therapy in PersAF.

3.
Virology ; 600: 110214, 2024 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-39243656

RESUMO

Pseudorabies virus is a swine alpha-herpesvirus. We demonstrated that alpha-herpesvirus infection downregulates HSF1, a master transcription factor in the heat shock response. The serine/threonine protein kinase activity of late viral protein UL13 is indispensable for HSF1 depletion and phosphorylation, and UL13 does not degrade HSF1 posttranslationally but inhibits the HSF1 mRNA level. Importantly, UL13 increased HSF1 activity even though it reduced HSF1 mRNA. Furthermore, viral replication markedly decreased in the HSF1 knockout cell line or in the presence of an HSF1-specific inhibitor. Interestingly, HSF1 knockout accelerated the activation of NF-κB and p38MAPK. The K96 loci of UL13 are important to induce high levels of IL-6, TNF-α, and IL-ß cytokines while playing a crucial role in promoting mild interstitial pneumonia, liver necrosis, and severe inflammatory cell infiltration in the footpad. Thus, UL13 steers the heat shock response to promote viral replication and the inflammatory response. IMPORTANCE: PRV is a ubiquitous pathogen that infects a variety of mammals, such as pigs, ruminants, carnivores, and rodents as well as human beings, causing enormous economic losses in the swine industry. Here, we employed PRV as a model to determine the relationship between α-herpesvirus and the inflammatory response. Overall, our findings indicated that PRV infection inhibits the level of HSF1 mRNA via the serine/threonine protein kinase activity of UL13. Additionally, we discovered that HSF1 was involved in NF-κB activation upon PRV infection. PRV UL13 orchestrates the level of HSF1 mRNA, HSF1 protein phosphorylation, and priming of the inflammatory response. Our study reveals a novel mechanism employed by UL13 serine/threonine protein kinase activity to promote the inflammatory response, providing novel clues for therapy against alpha-herpesvirus infection.

4.
J Colloid Interface Sci ; 677(Pt A): 909-917, 2024 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-39126809

RESUMO

Since the intensification of global environmental pollution and energy shortages, photocatalytic CO2 reduction reaction (CO2RR) has emerged as a promising strategy to convert solar energy into clean chemical energy. Herein, we construct a robust and efficient heterojunction construction photocatalyst for CO2RR, composed of the highly reactive CeNi quantum dots (CeNi QDs) and nickel metal-organic layer (Ni-MOL) ultrathin nanosheets. This design facilitates the rapid separation of photogenerated charge carriers, as confirmed by X-ray photoelectron spectroscopy (XPS), photoluminescence spectroscopy (PL) and other characterizations. Mechanistic studies with in situ diffuse reflectance Fourier transform infrared spectroscopy (in situ DRIFTS) and the d-band center calculation indicate that the propensity of photocatalyst for CO2 absorption and CO desorption, leading to high performance and selectivity. The optimized loading amount of CeNi quantum dots and modified structure result in a CO yield of 30.53 mmol·g-1 within 6 h under irradiation. This work not only paves a new and convenient way for developing high-activity quantum dot materials for CO2RR but also exploits novel avenues to fabricate more heterojunction composites for solar energy conversion.

5.
Environ Pollut ; 358: 124533, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-38996994

RESUMO

Electrocatalytic coupled biofilter (EBF) technology organically integrates the characteristics of electrochemistry and microbial redox, providing ideas for effectively improving biological treatment performance. In this study, an EBF system was developed for enhanced degradation of cyclohexanone in contaminated water. Experimental results show that the system can effectively remove cyclohexanone in contaminated water. Under the optimal parameters, the removal rates of cyclohexanone, TP, NH4+-N and TN were 97.61 ± 1.31%, 76.31 ± 1.67%, 94.14 ± 2.13% and 95.87 ± 1.01% respectively. Degradation kinetics studies found that electrolysis, adsorption, and biodegradation pathways play a major role in the degradation of cyclohexanone. Microbial community analysis indicates that voltage can affect the structure of the microbial community, with the dominant genera shifting from Acidovorax (0 V) to Brevundimonas (0.7 V). Additionally, Acidovorax, Cupriavidus, Ralstonia, and Hydrogenophaga have high abundance in the biofilm and can effectively metabolize cyclohexanone and its intermediates, facilitating the removal of cyclohexanone. In summary, this research can guide the development and construction of highly stable EBF systems and is expected to be used for advanced treatment of industrial wastewater containing cyclohexanone.


Assuntos
Biodegradação Ambiental , Cicloexanonas , Filtração , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Cicloexanonas/química , Cicloexanonas/metabolismo , Águas Residuárias/química , Eliminação de Resíduos Líquidos/métodos , Filtração/métodos , Poluentes Químicos da Água/metabolismo
6.
Materials (Basel) ; 17(14)2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-39063681

RESUMO

In this paper, the deformation behavior of UNS S32750 (S32750) duplex stainless steel during low cycle fatigue was studied by controlling the number of cycles. The microstructure of the specimens under different cycles was characterized by optical microscope (OM), scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscope (TEM). The microhardness of the two phases was measured by a digital microhardness instrument. The results showed that the microhardness of ferrite increases significantly after the first 4000 cycles, while the austenite shows a higher strain hardening rate after fatigue fracture, and the microhardness of ferrite and austenite increases by 23 HV and 87 HV, respectively. The two-phase kernel average misorientation (KAM) diagram showed that the continuous accumulation of plastic deformation easily leads to the initiation of cracks inside the austenite and at the phase boundaries. The evolution of dislocation morphology in the two phases was obviously different. With the increase in cycle number, the dislocation in ferrite gradually transforms from dislocation bundles and a dislocation array to a sub-grain structure, while the dislocation in austenite gradually develops from dipole array to an ordered Taylor lattice network structure.

7.
J Endocr Soc ; 8(8): bvae120, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38974987

RESUMO

Context: Cardiovascular disease (CVD) in transgender women (TW) may be affected by gender-affirming hormone therapy (GAHT) and HIV, but few data compare TW on contemporary GAHT to well-matched controls. Objective: We compared CVD burden and biomarker profiles between TW and matched cisgender men (CM). Methods: Adult TW on GAHT (n = 29) were recruited for a cross-sectional study (2018-2020). CM (n = 48) from the former Multicenter AIDS Cohort Study were matched 2:1 to TW on HIV serostatus, age ±5 years, race/ethnicity, BMI category and antiretroviral therapy (ART) type. Cardiac parameters were measured by CT and coronary atherosclerosis by coronary CT angiography; sex hormone and biomarker concentrations were measured centrally from stored samples. Results: Overall, median age was 53 years and BMI 29 kg/m2; 69% were non-white. All participants with HIV (71%) had viral suppression on ART. Only 31% of TW had testosterone suppression (<50 ng/dL, TW-S). Traditional CVD risk factors were similar between groups, except that TW-S had higher BMI than TW with non-suppressed testosterone (TW-T). TW-S had no evidence of non-calcified coronary plaque or advanced coronary stenosis, whereas TW-T and CM had similar burden. TW had lower prevalence of any coronary plaque, calcified plaque and mixed plaque than CM, regardless of testosterone concentrations and HIV serostatus. Estradiol but not testosterone concentrations moderately and negatively correlated with the presence of coronary plaque and stenosis. Small sample size limited statistical power. Conclusion: Older TW with suppressed total testosterone on GAHT had no CT evidence of non-calcified coronary plaque or advanced coronary stenosis. Longitudinal studies to understand relationships between GAHT and CVD risk in TW are needed.

8.
Artigo em Inglês | MEDLINE | ID: mdl-38848006

RESUMO

BACKGROUND: Catheter ablation is recognized as an effective treatment for atrial fibrillation (AF). Despite its effectiveness, significant sex-specific differences have been observed, which influence the outcomes of the procedure. This study explores these differences in a cohort of patients with persistent AF. We aim to assess sex differences in baseline characteristics, symptoms, quality of life, imaging findings, and response to catheter ablation in patients with persistent AF. METHODS: This post hoc analysis of the DECAAF II trial evaluated 815 patients (161 females, 646 males). Between July 2016 and January 2020, participants were enrolled and randomly assigned to receive either personalized ablation targeting left atrial (LA) fibrosis using DE-MRI in conjunction with pulmonary vein isolation (PVI) or PVI alone. In this analysis, we aimed to compare female and male patients in the full cohort in terms of demographics, risk factors, medications, and outcomes such as AF recurrence, AF burden, LA volume reduction assessed by LGE-MRI before and 3 months after ablation, quality of life assessed by the SF-36 score, and safety outcomes. Statistical methods included t-tests, chi-square, and multivariable Cox regression. RESULTS: Females were generally older with more comorbidities and experienced higher rates of arrhythmia recurrence post-ablation (53.3% vs. 40.2%, p < 0.01). Females also showed a higher AF burden (21% vs. 16%, p < 0.01) and a smaller reduction in left atrial volume indexed to body surface area post-ablation compared to male patients (8.36 (9.94) vs 11.35 (13.12), p-value 0.019). Quality of life scores were significantly worse in females both pre- and post-ablation (54 vs. 66 pre-ablation; 69 vs. 81 post-ablation, both p < 0.01), despite similar improvements across sexes. Safety outcomes and procedural parameters were similar between male and female patients. CONCLUSION: The study highlights significant differences in the outcomes of catheter ablation of persistent AF between sexes, with female patients showing worse quality of life, higher recurrence of AF and AF burden after ablation, and worse LA remodeling.

9.
Heart Lung ; 68: 107-115, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943717

RESUMO

BACKGROUND: Heart failure (HF) imposes a substantial burden on older adults, and healthy diets and lifestyles may bring with benefits. However, quantifiable studies on the dietary and lifestyle risk factors for HF are scant. The Oxidative Balance Score (OBS) reflects the oxidative stress status of dietary components and lifestyle factors, but its relationship with HF risk is unclear. OBJECTIVE: We aims to explore the association between OBS and the prevalence of HF. METHODS: Using data from the National Health and Nutrition Examination Survey (NHANES) 2005-2018, the association between OBS and the HF prevalence was analyzed by weighted logistic regression and restricted cubic splines (RCS). Subgroup and sensitivity analyses assessed the stability of the results. RESULTS: The prevalence of HF in the cohort of 6238 older adults was 5.55 %. Compared to the lowest quintile, the adjusted ORs for HF in the highest quintile of OBS and lifestyle OBS were 0.57 (95 % CI: 0.33,0.97) and 0.21 (95 %CI: 0.09,0.50), respectively. The association between OBS and HF prevalence remained stable across different models and subgroups. RCS revealed a potential inflection point. Sensitivity analysis validated the negative association between OBS and HF prevalence, and the correlation analysis between OBS and serum γ-glutamyltransferase (γ-GGT) confirmed the reliability of the study design. CONCLUSION: The OBS is negatively associated with HF prevalence in older adults, and may help prevent HF in this population.

10.
Nat Immunol ; 25(8): 1383-1394, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38942990

RESUMO

The immunological mechanisms underlying chronic colitis are poorly understood. T follicular helper (TFH) cells are critical in helping B cells during germinal center reactions. In a T cell transfer colitis model, a lymphoid structure composed of mature dendritic cells (DCs) and TFH cells was found within T cell zones of colonic lymphoid follicles. TFH cells were required for mature DC accumulation, the formation of DC-T cell clusters and colitis development. Moreover, DCs promoted TFH cell differentiation, contributing to colitis development. A lineage-tracing analysis showed that, following migration to the lamina propria, TFH cells transdifferentiated into long-lived pathogenic TH1 cells, promoting colitis development. Our findings have therefore demonstrated the reciprocal regulation of TFH cells and DCs in colonic lymphoid follicles, which is critical in chronic colitis pathogenesis.


Assuntos
Diferenciação Celular , Colite , Células Dendríticas , Células T Auxiliares Foliculares , Animais , Células Dendríticas/imunologia , Colite/imunologia , Colite/patologia , Células T Auxiliares Foliculares/imunologia , Camundongos , Diferenciação Celular/imunologia , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , Células Th1/imunologia , Colo/imunologia , Colo/patologia , Camundongos Knockout , Centro Germinativo/imunologia , Camundongos Transgênicos
11.
Animal Model Exp Med ; 7(3): 337-346, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38859745

RESUMO

BACKGROUND: This study aimed to construct and characterize a humanized influenza mouse model expressing hST6GAL1. METHODS: Humanized fragments, consisting of the endothelial cell-specific K18 promoter, human ST6GAL1-encoding gene, and luciferase gene, were microinjected into the fertilized eggs of mice. The manipulated embryos were transferred into the oviducts of pseudopregnant female mice. The offspring were identified using PCR. Mice exhibiting elevated expression of the hST6GAL1 gene were selectively bred for propagation, and in vivo analysis was performed for screening. Expression of the humanized gene was tested by performing immunohistochemical (IHC) analysis. Hematologic and biochemical analyses using the whole blood and serum of humanized hST6GAL1 mice were performed. RESULTS: Successful integration of the human ST6GAL1 gene into the mouse genome led to the overexpression of human SiaT ST6GAL1. Seven mice were identified as carrying copies of the humanized gene, and the in vivo analysis indicated that hST6GAL1 gene expression in positive mice mirrored influenza virus infection characteristics. The IHC results revealed that hST6GAL1 was expressed in the lungs of humanized mice. Moreover, the hematologic and biochemical parameters of the positive mice were within the normal range. CONCLUSION: A humanized influenza mouse model expressing the hST6GAL1 gene was successfully established and characterized.


Assuntos
Modelos Animais de Doenças , Sialiltransferases , Animais , Humanos , Camundongos , Feminino , Sialiltransferases/genética , Sialiltransferases/metabolismo , Antígenos CD/metabolismo , Antígenos CD/genética , Infecções por Orthomyxoviridae , Camundongos Transgênicos , Antígenos de Superfície/metabolismo , Antígenos de Superfície/genética , beta-D-Galactosídeo alfa 2-6-Sialiltransferase
12.
Bioresour Technol ; 403: 130883, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38788807

RESUMO

Electrodes with superior stability and sensitivity are highly desirable in advancing the toxicity detection efficiency of microbial fuel cells (MFCs). Herein, boron-doped reduced graphene oxide (B-rGO) was synthesized and utilized as an efficient cathode candidate in an MFCs system for sensitive sodium dodecylbenzene sulfonate (SDBS) detection. Boron doping introduces additional defects and improves the dispersibility and oxygen permeability, thereby enhancing the oxygen reduction reaction (ORR) efficiency. The B-rGO-based cathode has demonstrated significantly improved output voltage and power density, marking improvements of 75 % and 58 % over their undoped counterparts, respectively. Furthermore, it also exhibited remarkable linear sensitivity to SDBS concentrations across a broad range (0.2-15 mg/L). Notably, the cathode maintained excellent stability within the test range and showed significant reversibility for SDBS concentrations between 0.2 and 3 mg/L. The highly sensitive and stable B-rGO-based cathode is inspiring for developing more practical and cost-effective toxicant sensing devices.


Assuntos
Fontes de Energia Bioelétrica , Boro , Eletrodos , Grafite , Grafite/química , Boro/química , Benzenossulfonatos/química , Oxirredução , Óxidos/química
13.
J Ethnopharmacol ; 331: 118330, 2024 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-38740109

RESUMO

ETHNOPHARMACOLOGICAL RELEVANCE: Chromolaenaodorata (L.) R.M. King & H. Rob, a perennial herb, has been traditionally utilized as a herbal remedy for treating leech bites, soft tissue wounds, burn wounds, skin infections, and dento-alveolitis in tropical and subtropical regions. AIM OF THE STUDY: The present study was to analyze the active fraction of C. odorata ethanol extract and investigate its hemostatic, anti-inflammatory, wound healing, and antimicrobial properties. Additionally, the safety of the active fraction as an external preparation was assessed through skin irritation and allergy tests. MATERIALS AND METHODS: The leaves and stems of C. odorata were initially extracted with ethanol, followed by purification through AB-8 macroporous adsorption resin column chromatography to yield different fractions. These fractions were then screened for hemostatic activity in mice and rabbits to identify the active fraction. Subsequently, the hemostatic effect of the active fraction was assessed through the bleeding time of the rabbit ear artery in vivo and the coagulant time of rabbit blood in vitro. The anti-inflammatory activity of the active fraction was tested on mice ear edema induced by xylene and rat paw edema induced by carrageenin. Furthermore, the active fraction's promotion effect on wound healing was evaluated using a rat skin injury model, and skin safety tests were conducted on rabbits and guinea pigs. Lastly, antimicrobial activities against two Gram-positive bacteria (G+, Staphylococcus aureus and S. epidermidis) and three Gram-negative bacteria (G-, Escherichia coli, Klebsiella pneumoniae, and Pseudomonas aeruginosa) were determined using the plate dilution method. RESULTS: The ethanol extract of C. odorata leaves and stems was fractionated into 30%, 60%, and 90% ethanol eluate fractions. These fractions demonstrated hemostatic activity, with the 30% ethanol eluate fraction (30% EEF) showing the strongest effect, significantly reducing bleeding time (P < 0.05). A concentration of 1.0 g/mL of the 30% EEF accelerated cutaneous wound healing in rats on the 3rd, 6th, and 9th day post-operation, with the healing effect increasing over time. No irritation or allergy reactions were observed in rabbits and guinea pigs exposed to the 30% EEF. Additionally, the 30% EEF exhibited mild inhibitory effect on mice ear and rat paw edema, as well as antimicrobial activity against tested bacteria, with varying minimal inhibitory concentration (MIC) values. CONCLUSIONS: The 30% EEF demonstrated a clear hemostatic effect on rabbit bleeding time, a slight inhibitory effect on mice ear edema and rat paw edema, significant wound healing activity in rats, and no observed irritation or allergic reactions. Antibacterial activity was observed against certain clinically isolated bacteria, particularly the G- bacteria. This study lays the groundwork for the potential development and application of C. odorata in wound treatment.


Assuntos
Anti-Inflamatórios , Chromolaena , Edema , Etanol , Hemostáticos , Extratos Vegetais , Cicatrização , Animais , Coelhos , Cicatrização/efeitos dos fármacos , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/isolamento & purificação , Camundongos , Masculino , Hemostáticos/farmacologia , Etanol/química , Chromolaena/química , Edema/tratamento farmacológico , Edema/induzido quimicamente , Ratos , Pele/efeitos dos fármacos , Feminino , Anti-Infecciosos/farmacologia , Anti-Infecciosos/isolamento & purificação , Folhas de Planta/química , Hipersensibilidade/tratamento farmacológico , Xilenos , Caules de Planta/química
14.
Bioact Mater ; 39: 1-13, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38783924

RESUMO

Irregular articular cartilage injury is a common type of joint trauma, often resulting from intense impacts and other factors that lead to irregularly shaped wounds, the limited regenerative capacity of cartilage and the mismatched shape of the scaffods have contributed to unsatisfactory therapeutic outcomes. While injectable materials are a traditional solution to adapt to irregular cartilage defects, they have limitations, and injectable materials often lack the porous microstructures favorable for the rapid proliferation of cartilage cells. In this study, an injectable porous polyurethane scaffold named PU-BDO-Gelatin-Foam (PUBGF) was prepared. After injection into cartilage defects, PUBGF forms in situ at the site of the defect and exhibits a dynamic microstructure during the initial two weeks. This dynamic microstructure endows the scaffold with the ability to retain substances within its interior, thereby enhancing its capacity to promote chondrogenesis. Furthermore, the chondral repair efficacy of PUBGF was validated by directly injecting it into rat articular cartilage injury sites. The injectable PUBGF scaffold demonstrates a superior potential for promoting the repair of cartilage defects when compared to traditional porous polyurethane scaffolds. The substance retention ability of this injectable porous scaffold makes it a promising option for clinical applications.

15.
Materials (Basel) ; 17(9)2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38730882

RESUMO

Duplex stainless steels are widely used in many fields due to their excellent corrosion resistance and mechanical properties. However, it is a challenge to achieve duplex microstructure and excellent properties through additive manufacturing. In this work, a 0.09% N 25Cr-type duplex stainless steel was prepared by additive manufacturing (AM) and heat treatment, and its corrosion resistance was investigated. The results show that, compared with S32750 duplex stainless steel prepared by a conventional process, the combination value of film resistance and charge transfer resistance of AM duplex stainless steel was increased by 3.2-5.5 times and the pitting potential was increased by more than 100 mV. The disappearance of residual thermal stress and the reasonable distribution of Cr and N elements in the two phases are the reasons for the improvement of the corrosion resistance of AM duplex stainless steel after heat treatment. In addition, the extremely high purity of AM duplex stainless steel with no visible inclusions resulted in a higher corrosion resistance exhibited at lower pitting-resistance-equivalent number values.

16.
J Biomed Opt ; 29(4): 046008, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38659998

RESUMO

Significance: Optical imaging is a non-invasive imaging technology that utilizes near-infrared light, allows for the image reconstruction of optical properties like diffuse and absorption coefficients within the tissue. A recent trend is to use signal processing techniques or new light sources and expanding its application. Aim: We aim to develop the reflective optical imaging using the chaotic correlation technology with chaotic laser and optimize the quality and spatial resolution of reflective optical imaging. Approach: Scattering medium was measured using reflective configuration in different inhomogeneous regions to evaluate the performance of the imaging system. The accuracy of the recovered optical properties was investigated. The reconstruction errors of absorption coefficients and geometric centers were analyzed, and the feature metrics of the reconstructed images were evaluated. Results: We showed how chaotic correlation technology can be utilized for information extraction and image reconstruction. This means that a higher signal-to-noise ratio and image reconstruction of inhomogeneous phantoms under different scenarios successfully were achieved. Conclusions: This work highlights that the peak values of correlation of chaotic exhibit smaller reconstruction error and better reconstruction performance in optical imaging compared with reflective optical imaging with the continuous wave laser.


Assuntos
Processamento de Imagem Assistida por Computador , Lasers , Imagem Óptica , Imagens de Fantasmas , Espalhamento de Radiação , Imagem Óptica/métodos , Processamento de Imagem Assistida por Computador/métodos , Razão Sinal-Ruído , Dinâmica não Linear , Algoritmos , Desenho de Equipamento
17.
Europace ; 26(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38646912

RESUMO

AIMS: Traditional atrial fibrillation (AF) recurrence after catheter ablation is reported as a binary outcome. However, a paradigm shift towards a more granular definition, considering arrhythmic or symptomatic burden, is emerging. We hypothesize that ablation reduces AF burden independently of conventional recurrence status in patients with persistent AF, correlating with symptom burden reduction. METHODS AND RESULTS: Ninety-eight patients with persistent AF from the DECAAF II trial with pre-ablation follow-up were included. Patients recorded daily single-lead electrocardiogram (ECG) strips, defining AF burden as the proportion of AF days among total submitted ECG days. The primary outcome was atrial arrhythmia recurrence. The AF severity scale was administered pre-ablation and at 12 months post-ablation. At follow-up, 69 patients had atrial arrhythmia recurrence and 29 remained in sinus rhythm. These patients were categorized into a recurrence (n = 69) and a no-recurrence group (n = 29). Both groups had similar baseline characteristics, but recurrence patients were older (P = 0.005), had a higher prevalence of hyperlipidaemia (P = 0.007), and had a larger left atrial (LA) volume (P = 0.01). There was a reduction in AF burden in the recurrence group when compared with their pre-ablation burden (65 vs. 15%, P < 0.0001). Utah Stage 4 fibrosis and diabetes predicted less improvement in AF burden. The symptom severity score at 12 months post-ablation was significantly reduced compared with the pre-ablation score in the recurrence group, and there was a significant correlation between the reduction in symptom severity score and the reduction in AF burden (R = 0.39, P = 0.001). CONCLUSION: Catheter ablation reduces AF burden, irrespective of arrhythmia recurrence post-procedure. There is a strong correlation between AF burden reduction and symptom improvement post-ablation. Notably, elevated LA fibrosis impedes AF burden decrease following catheter ablation.


Assuntos
Fibrilação Atrial , Ablação por Cateter , Recidiva , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fibrilação Atrial/cirurgia , Fibrilação Atrial/fisiopatologia , Fibrilação Atrial/diagnóstico , Ablação por Cateter/métodos , Eletrocardiografia , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Estudos Prospectivos
18.
J Muscle Res Cell Motil ; 45(3): 95-113, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38625452

RESUMO

We examined the integrity of flash-frozen and cryo-sectioned cardiac muscle preparations (introduced by Feng and Jin, 2020) by assessing tension transients in response to sinusoidal length changes at varying frequencies (1-100 Hz) at 25 °C. Using 70-µm-thick sections, we isolated fiber preparations to study cross-bridge (CB) kinetics: preparations were activated by saturating Ca2+ as well as varying concentrations of ATP and phosphate (Pi). Our results showed that, compared to ordinary skinned fibers, in-series stiffness decreased to 1/2, which resulted in a decrease of isometric tension to 62%, but CB kinetics and Ca2+ sensitivity were little affected. The pCa study demonstrated that the rate constant of the force generation step (2πb) is proportionate to [Ca2+] at < 5 µM, suggesting that the activation mechanism can be described by a simple second order reaction. We also found that tension, stiffness, and magnitude parameters are related to [Ca2+] by the Hill equation, with a cooperativity coefficient of 4-5, which is consistent with the fact that Ca2+ activation mechanisms involve cooperative multimolecular interactions. Our results support the long-held hypothesis that Process C (Phase 2) represents the CB detachment step, and Process B (Phase 3) represents the force generation step. Moreover, we discovered that constant H may represent the work-performing step in cardiac preparations. Our experiments demonstrate excellent CB kinetics with two well-defined exponentials that can be more distinguished than those found using ordinary skinned fibers. Flash-frozen and cryo-sectioned preparations are especially suitable for multi-institutional collaborations nationally and internationally because of their ease of transportation.


Assuntos
Cálcio , Músculos Papilares , Cálcio/metabolismo , Animais , Cinética , Músculos Papilares/metabolismo , Músculos Papilares/fisiologia , Fenômenos Biomecânicos/fisiologia
19.
Nat Commun ; 15(1): 3200, 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38615014

RESUMO

Histone lysine crotonylation (Kcr), as a posttranslational modification, is widespread as acetylation (Kac); however, its roles are largely unknown in kidney fibrosis. In this study, we report that histone Kcr of tubular epithelial cells is abnormally elevated in fibrotic kidneys. By screening these crotonylated/acetylated factors, a crotonyl-CoA-producing enzyme ACSS2 (acyl-CoA synthetase short chain family member 2) is found to remarkably increase histone 3 lysine 9 crotonylation (H3K9cr) level without influencing H3K9ac in kidneys and tubular epithelial cells. The integrated analysis of ChIP-seq and RNA-seq of fibrotic kidneys reveal that the hub proinflammatory cytokine IL-1ß, which is regulated by H3K9cr, play crucial roles in fibrogenesis. Furthermore, genetic and pharmacologic inhibition of ACSS2 both suppress H3K9cr-mediated IL-1ß expression, which thereby alleviate IL-1ß-dependent macrophage activation and tubular cell senescence to delay renal fibrosis. Collectively, our findings uncover that H3K9cr exerts a critical, previously unrecognized role in kidney fibrosis, where ACSS2 represents an attractive drug target to slow fibrotic kidney disease progression.


Assuntos
Histonas , Nefropatias , Humanos , Lisina , Ativação de Macrófagos , Rim , Senescência Celular , Células Epiteliais , Interleucina-1beta , Acetato-CoA Ligase
20.
IEEE Trans Neural Netw Learn Syst ; 35(9): 11634-11648, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38466605

RESUMO

The nature of heterophilous graphs is significantly different from that of homophilous graphs, which causes difficulties in early graph neural network (GNN) models and suggests aggregations beyond the one-hop neighborhood. In this article, we develop a new way to implement multiscale extraction via constructing Haar-type graph framelets with desired properties of permutation equivariance, efficiency, and sparsity, for deep learning tasks on graphs. We further design a graph framelet neural network model permutation equivariant graph framelet augmented network (PEGFAN) based on our constructed graph framelets. The experiments are conducted on a synthetic dataset and nine benchmark datasets to compare the performance with other state-of-the-art models. The result shows that our model can achieve the best performance on certain datasets of heterophilous graphs (including the majority of heterophilous datasets with relatively larger sizes and denser connections) and competitive performance on the remaining.

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