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1.
Biomaterials ; 313: 122814, 2025 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-39243672

RESUMEN

Radiotherapy as a mainstay of in-depth cervical cancer (CC) treatment suffers from its radioresistance. Radiodynamic therapy (RDT) effectively reverses radio-resistance by generating reactive oxygen species (ROS) with deep tissue penetration. However, the photosensitizers stimulated by X-ray have high toxicity and energy attenuation. Therefore, X-ray responsive diselenide-bridged mesoporous silica nanoparticles (DMSNs) are designed, loading X-ray-activated photosensitizer acridine orange (AO) for spot blasting RDT like Trojan-horse against radio-resistance cervical cancer (R-CC). DMSNs can encapsulate a large amount of AO, in the tumor microenvironment (TME), which has a high concentration of hydrogen peroxide, X-ray radiation triggers the cleavage of diselenide bonds, leading to the degradation of DMSNs and the consequent release of AO directly at the tumor site. On the one hand, it solves the problems of rapid drug clearance, adverse distribution, and side effects caused by simple AO treatment. On the other hand, it fully utilizes the advantages of highly penetrating X-ray responsive RDT to enhance radiotherapy sensitivity. This approach results in ROS-induced mitochondria damage, inhibition of DNA damage repair, cell cycle arrest and promotion of cancer cell apoptosis in R-CC. The X-ray responsive DMSNs@AO hold considerable potential in overcoming obstacles for advanced RDT in the treatment of R-CC.


Asunto(s)
Nanopartículas , Dióxido de Silicio , Humanos , Animales , Rayos X , Nanopartículas/química , Femenino , Dióxido de Silicio/química , Ratones , Neoplasias del Cuello Uterino/terapia , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/patología , Especies Reactivas de Oxígeno/metabolismo , Fármacos Fotosensibilizantes/farmacología , Fármacos Fotosensibilizantes/uso terapéutico , Tolerancia a Radiación/efectos de los fármacos , Microambiente Tumoral/efectos de los fármacos , Ratones Desnudos , Células HeLa , Ratones Endogámicos BALB C , Apoptosis/efectos de los fármacos , Línea Celular Tumoral
2.
Onco Targets Ther ; 17: 755-763, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39282132

RESUMEN

Objective: PIK3CA-mutant non-small-cell lung cancer (NSCLC) is associated with other genetic mutations and may influence treatment strategies and clinical outcomes. We aimed to characterize PIK3CA mutations co-occurring with several major driver mutations using data from published cohorts and our medical center. Materials and Methods: We analyzed NSCLC patients harboring PIK3CA mutations from The Cancer Genome Atlas (TCGA) and Memorial Sloan Kettering (MSK) databases and retrospectively identified NSCLC patients with PIK3CA-mutants at a single medical center from our electronic records. The Log rank test was used to determine the association between PIK3CA mutations and overall survival (OS) in NSCLC patients. Results: Common hotspot mutations in PIK3CA were found in exon 9 (c.1633G > A, E545K, and c.1624G > A, E542K) and exon 20 (c.3140A > G, H1047R) in all cohorts. Co-occurring mutations of PIK3CA with EGFR, KRAS, and TP53 have been frequently observed in patients with NSCLC, with different percentages in these datasets generated by different background. PIK3CA mutations were observed to be significantly associated with poor OS in lung adenocarcinomas patients in the MSKCC cohort (hazard ratio [HR] = 0.519, 95% confidence interval [CI] = 0.301-0.896; P <0.05). Conclusion: PIK3CA co-occurring mutations in other genes may represent distinct subsets of NSCLC. Further elucidation of the roles of PIK3CA hotspot mutations combined with other driver mutations, including EGFR and KRAS, is needed to guide effective treatment in patients with advanced NSCLC.

3.
J Am Heart Assoc ; : e036555, 2024 Sep 18.
Artículo en Inglés | MEDLINE | ID: mdl-39291488

RESUMEN

Engaging in regular exercise and physical activity contributes to delaying the onset of cardiovascular diseases (CVDs). However, the physiological mechanisms underlying the benefits of regular exercise or physical activity in CVDs remain unclear. The disruption of mitochondrial homeostasis is implicated in the pathological process of CVDs. Exercise training effectively delays the onset and progression of CVDs by significantly ameliorating the disruption of mitochondrial homeostasis. This includes improving mitochondrial biogenesis, increasing mitochondrial fusion, decreasing mitochondrial fission, promoting mitophagy, and mitigating mitochondrial morphology and function. This review provides a comprehensive overview of the benefits of physical exercise in the context of CVDs, establishing a connection between the disruption of mitochondrial homeostasis and the onset of these conditions. Through a detailed examination of the underlying molecular mechanisms within mitochondria, the study illuminates how exercise can provide innovative perspectives for future therapies for CVDs.

4.
ACS Chem Neurosci ; 2024 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-39276340

RESUMEN

The dopamine D3 receptor (D3R) is important in the pathophysiology of various neuropsychiatric disorders, such as depression, bipolar disorder, schizophrenia, drug addiction, and Parkinson's disease. Positron emission tomography (PET) with innovative radioligands provides an opportunity to assess D3R in vivo and to elucidate D3R-related disease mechanisms. Herein, we present the synthesis of eight 18F-labeled phenylpiperazine-like D3R-selective radioligands possessing good radiochemical purity (>97%), in vitro stability (>95%), and befitting lipophilicity. Based on in vitro binding assays and static microPET studies, the phenylpiperazine-like radioligands [18F]FBPC01 and [18F]FBPC03 were chosen as lead radioligands targeting D3R. Molecular docking further elucidated their binding mechanism. Radiolabeling conditions were optimized and then applied to an automated radiolabeling process, affording products with high specific activity (>112 GBq/µmol). Dynamic rat PET study demonstrated the specific binding of [18F]FBPC01 and [18F]FBPC03 to D3R in the brain ventricles and the pituitary gland. Validated by dynamic PET data analysis, biodistribution study, and metabolism analysis, [18F]FBPC03 exhibited the highest PET signal-to-noise ratio, good D3R-specific binding in the brain ventricles and pituitary gland of rats with few off-target binding, negligible defluorination, and stable brain metabolism, which indicated that [18F]FBPC03 was a promising D3R radioligand.

5.
J Clin Lipidol ; 2024 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-39278776

RESUMEN

BACKGROUND: Patients suffering from sitosterolemia with ABCG5/8 mutation typically present with early-onset or rapidly progressive atherosclerosis. Their kindreds with partial genetic deficiencies of ABCG5/8 are often considered healthy. However, discerning sitosterolemia from its familial kindreds and hyperlipidemia subjects has remained challenging. METHODS: Here we retrospectively recruited seven families including 8 individuals diagnosed with sitosterolemia subjects, and 14 kindreds carrying single gene mutations. Additionally, 17 individuals with hyperlipidemia and 130 healthy controls served as positive and negative controls, respectively. A total of 6 phytosterols combined with cholesterol absorption indices (including sitosterol, campesterol, stigmasterol, and cholestanol) and cholesterol synthesis markers (desmosterol and 7-dehydrocholesterol), was compared across the aforementioned four groups. RESULTS: As expected, the sitosterolemia subjects with double mutations demonstrated significantly elevated levels of sitosterol and other cholesterol absorption indices. Meanwhile, sitosterolemia kindreds with single gene mutation showed a similar pattern of activated cholesterol-absorption ability to the hyperlipidemia group, but not as high as the double mutation group. Notably, the cholesterol-synthesis enzyme 7-dehydrocholesterol reductase displayed an increase in the hyperlipidemia group but a decrease in the sitosterolemia kindred group, suggesting a potential discriminative role of 7-dehydrocholesterol in distinguishing between these two groups. The combination of phytosterols was more valuable than clinical lipid index for sitosterolemia diagnosis. CONCLUSION: Our study revealed mild disruptions of cholesterol absorption capacities in sitosterolemia kindreds with single mutations. Furthermore, the combination of 6 phytosterols proved effective in distinguishing between sitosterolemia, its single mutation carriers, and hyperlipidemia patients.

6.
J Glaucoma ; 2024 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-39283689

RESUMEN

PRCIS: This research presents the burden and clinical characteristics of NVG in Zhongshan Ophthalmic Center, employing the most extensive sample size and the longest uninterrupted temporal duration so far, which may provide a theoretical reference for the effective prevention and diagnosis of NVG. PURPOSE: To summarize the burden and clinical characteristics of neovascular glaucoma (NVG) in a major tertiary care center in China. METHODS: The clinical data of NVG patients in Zhongshan Ophthalmic Center (ZOC) between 2012 and 2021 were collected retrospectively, including their age, sex, affected eye, best-corrected visual acuity (BCVA), intraocular pressure (IOP), clinical stage and aetiology. RESULTS: In this study, we included 1877 eyes of 1749 patients who developed NVG, with 2.01:1 ratio of male to female. Their mean age was 53.14±16.69 years and those aged 41-70 years (65.2%) were most affected. Monocular patients were more predominant in most of them (92.7%), while 7.3% were binocular and 1667 eyes (88.8%) were at the angle­closure stage. The BCVA and IOP were 2.42±0.70 logMAR and 38.6±12.2 mmHg, respectively. Over the decade, the number of NVG patients and the proportion of NVG patients among glaucoma patients showed an increasing trend, with annual percentage changes (APCs) of 9.1% (95% CI: 5.0-13.3%, P=0.001) and 4.8% (95% CI: 2.2-7.4%, P=0.003), respectively. The top three primary conditions were diabetic retinopathy (DR), retinal vein occlusion (RVO), and retinal detachment (RD). Moreover, the APCs for the constituent ratio of DR and RVO were 4.4% (95% CI: 0.5-8.4%, P=0.031) and ï¹£4.6% (95% CI: ï¹£8.4% to ï¹£0.7%, P=0.028), respectively. However, the first and second causes of NVG in minors (<18 years old) were Coat's disease and ocular tumours, followed by RD and RVO in third place. The top cause of NVG in patients aged 65 years and older was RVO. CONCLUSIONS: The burden of NVG is increasing, emphasizing the need to improve preventive strategies focusing on primary diseases such as DR, RVO, and RD, particularly the increasing proportion of DR cases and the previously underemphasized RD patients, while also highlighting the differences in primary diseases across different age groups.

7.
Appl Ergon ; 122: 104373, 2024 Sep 03.
Artículo en Inglés | MEDLINE | ID: mdl-39232339

RESUMEN

The metro is susceptible to disruption risks and requires a system response capability to build resilience to manage disruptions. Achieving such resilient response state requires readiness in both the technology side, e.g., utilizing digital technologies (DTs) to monitor system components, and the human factors side, e.g., fostering positive human coping capabilities; however, these two sides are usually considered independently, without sufficient integration. This paper aims to develop and empirically test a model in which monitoring-enabled DTs, employees' reactions, and their positive capabilities are simultaneously considered in terms of their interplay and impact on system response capability. The results showed that while DTs for monitoring physical components enhanced perceived management commitment and fostered collective efficacy, DTs for monitoring human components increased psychological strain and inhibited improvisation capability, creating a "double-edged sword" effect on system response capability. Additionally, explicit management commitment buffered the adverse effect of DTs-induced psychological strain on individual improvisation.

8.
Mar Biotechnol (NY) ; 2024 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-39235651

RESUMEN

As human activities increase and environmental changes persist, increased ultraviolet B (UVB) radiation in aquatic ecosystems poses significant threats to aquatic life. This study, through transcriptomic analysis of the mantle tissue of Crassostrea gigas following UVB radiation exposure, identified and validated two key transcription factors, CgRunx1 and CgCBFß. The highest expression levels of CgRunx1 and CgCBFß in the mantle suggest their pivotal roles in this tissue. Co-immunoprecipitation experiments revealed that CgRunx1 and CgCBFß could form heterodimers and interact with each other. Furthermore, this study assessed the impact of UVB radiation on the levels of reactive oxygen species of the C. gigas, speculating that CgRunx1, as a potential redox-sensitive transcription factor, might be regulated by intracellular ROS. Through screening and binding site prediction analysis of target genes, coupled with dual-luciferase reporter assays, we verified that CgRunx1 might participate in regulating the biomineralization and autophagy processes in C. gigas by activating the transcriptional expression of target genes Transport and Golgi organization 1 and V-type proton ATPase catalytic subunit A. These findings provide new insights into the molecular response mechanisms of the C. gigas to UVB radiation and lay an important foundation for studying the adaptive evolution of bivalves to environmental stress.

9.
Org Lett ; 2024 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-39230394

RESUMEN

Re-examination of the claimed isolation and X-ray characterization of di-p-tolyl and dimesityl 1,2-disulfoxides from thermolysis of the corresponding aryl sulfinimines and thiosulfinates showed that the isolated disulfide dioxides are instead the well-known isomeric thiosulfonates, as confirmed by XAS, DART-MS, X-ray, IR and NMR methods. Concerns with the original X-ray structures are addressed. Our results agree with the DFT prediction of very weak diaryl 1,2-disulfoxide S-S bond dissociation enthalpies. For now, room-temperature-stable noncyclic 1,2-disulfoxides remain unknown.

10.
Artículo en Inglés | MEDLINE | ID: mdl-39222277

RESUMEN

PURPOSE: This research aimed to assess the impact of ticagrelor and clopidogrel on coronary microvascular dysfunction (CMD) and prognosis following acute myocardial infarction (AMI), using the angiography-derived index of microcirculatory resistance (angio-IMR) as a non-invasive assessment tool. METHODS: In this retrospective study, angio-IMR was performed to evaluate CMD before and after dual antiplatelet therapy (DAPT) with either ticagrelor (90 mg twice daily, n = 184) or clopidogrel (75 mg once daily, n = 72). The primary endpoint is the improvement of CMD evaluated by angio-IMR (delta angio-IMR) following DAPT. Secondary endpoints included myocardial reinfarction and readmission for heart failure during 2-year follow-up. RESULTS: Compared with clopidogrel, ticagrelor exhibited a significantly higher delta angio-IMR [- 3.09 (5.14) versus - 1.99 (1.91), P = 0.008], indicating a superior improvement of CMD with ticagrelor treatment. Multivariate Cox regression indicated that ticagrelor treatment was related to a reduced risk of readmission for heart failure [8 (4.3) versus 9 (12.5), adjusted HR = 0.329; 95% CI = 0.116-0.934; P = 0.018] and myocardial reinfarction [7 (3.8) versus 8 (11.1), adjusted HR = 0.349; 95% CI = 0.125-0.975; P = 0.026]. Furthermore, ticagrelor treatment serves as an independent predictor of readmission for heart failure (HR = 0.322; 95% CI = 0.110-0.943; P = 0.039). CONCLUSION: The results of this study indicate a potential association between ticagrelor treatment and improved CMD, as well as a reduced risk of cardiovascular events, including myocardial reinfarction and readmission for heart failure in AMI patients. Further randomized controlled trials are necessary to confirm the potential benefits of ticagrelor on CMD and cardiovascular prognosis. This clinical trial was registered in www. CLINICALTRIALS: gov (NCT05978726).

11.
BMC Rheumatol ; 8(1): 36, 2024 Aug 21.
Artículo en Inglés | MEDLINE | ID: mdl-39164762

RESUMEN

BACKGROUND: This study aimed to investigate the accuracy of identifying enthesitis along with other inflammatory lesions and structural lesions on the MRI of the sacroiliac joints (SIJ) by readers of varying experience and how training sessions and workshops could help improve the accuracy. METHODS: A total of 224 patients with clinical diagnosis of axial spondyloarthritis who underwent SIJ MRI examinations were retrospectively included in this study. Three readers with 5 years, 3 years and 1 year of experience in musculoskeletal imaging were invited to review the SIJ MRI images independently, while the imaging reports of a senior radiologist (> 10 years' experience) were used as reference. After the first round of image review, a training session and a workshop on the imaging of SIJ in spondyloarthritis were held and the three readers were asked to review the images in the second round. We calculated the accuracy of identifying inflammatory and structural lesions of the three readers as well as the intra-reader agreement. RESULTS: Enthesitis could be observed in 52.23% of the axial spondyloarthritis patients, while 81.58% of the patients with enthesitis were accompanied with bone marrow edema. All the three readers showed better accuracy at identifying structural lesions than inflammatory lesions. In the first round of image review, the three readers only correctly identified 15.07%, 2.94% and 0.74% of the enthesitis sites. After the training session and workshop, the accuracy rose to 61.03%, 39.34% and 20.22%. The intra-reader agreement of enthesitis calculated as Cohen's kappa was 0.23, 0.034 and 0.014, respectively. CONCLUSION: Readers with less experience in musculoskeletal imaging showed lower accuracy of identifying inflammatory lesions, notably enthesitis. Training sessions and workshops could help improve the diagnostic accuracy of the junior readers.

12.
Artículo en Inglés | MEDLINE | ID: mdl-39120987

RESUMEN

Multi-instance learning (MIL) is a widely applied technique in practical applications that involve complex data structures. MIL can be broadly categorized into two types: traditional methods and those based on deep learning. These approaches have yielded significant results, especially regarding their problem-solving strategies and experiment validation, providing valuable insights for researchers in the MIL field. However, considerable knowledge is often trapped within the algorithm, leading to subsequent MIL algorithms that rely solely on the model's data fitting to predict unlabeled samples. This results in a significant loss of knowledge and impedes the development of more powerful models. In this article, we propose a novel data-driven knowledge fusion for deep MIL (DKMIL) algorithm. DKMIL adopts a completely different idea from existing deep MIL methods by analyzing the decision-making of key samples in the dataset (referred to as the data-driven) and using the knowledge fusion module designed to extract valuable information from these samples to assist the model's learning. In other words, this module serves as a new interface between data and the model, providing strong scalability and enabling prior knowledge from existing algorithms to enhance the model's learning ability. Furthermore, to adapt the downstream modules of the model to more knowledge-enriched features extracted from the data-driven knowledge fusion (DDKF) module, we propose a two-level attention (TLA) module that gradually learns shallow-and deep-level features of the samples to achieve more effective classification. We will prove the scalability of the knowledge fusion module and verify the efficiency of the proposed architecture by conducting experiments on 62 datasets across five categories.

13.
Cardiovasc Diabetol ; 23(1): 300, 2024 Aug 16.
Artículo en Inglés | MEDLINE | ID: mdl-39152477

RESUMEN

BACKGROUND: Diabetes mellitus (DM) and coronary microvascular dysfunction (CMD) increase the risk of adverse cardiac events in patients with non-ST-segment elevation myocardial infarction (NSTEMI). This study aimed to evaluate the combined risk estimates of DM and CMD, assessed by the angiography-derived index of microcirculatory resistance (angio-IMR), in patients with NSTEMI. METHODS: A total of 2212 patients with NSTEMI who underwent successful percutaneous coronary intervention (PCI) were retrospectively enrolled from three centers. The primary outcome was a composite of cardiac death or readmission for heart failure at a 2-year follow-up. RESULTS: Post-PCI angio-IMR did not significantly differ between the DM group and the non-DM group (20.13 [17.91-22.70] vs. 20.19 [18.14-22.77], P = 0.530). DM patients exhibited a notably higher risk of cardiac death or readmission for heart failure at 2 years compared to non-DM patients (9.5% vs. 5.4%, P < 0.001). NSTEMI patients with both DM and CMD experienced the highest cumulative incidence of cardiac death or readmission for heart failure at 2 years (24.0%, P < 0.001). The combination of DM and CMD in NSTEMI patients were identified as the most powerful independent predictor for cardiac death or readmission for heart failure at 2 years (adjusted HR: 7.894, [95% CI, 4.251-14.659], p < 0.001). CONCLUSIONS: In patients with NSTEMI, the combination of DM and CMD is an independent predictor of cardiac death or readmission for heart failure. Angio-IMR could be used as an additional evaluation tool for the management of NSTEMI patients with DM. TRIAL REGISTRATION: URL: https://www. CLINICALTRIALS: gov ; Unique identifier: NCT05696379.


Asunto(s)
Angiografía Coronaria , Circulación Coronaria , Diabetes Mellitus , Microcirculación , Infarto del Miocardio sin Elevación del ST , Readmisión del Paciente , Intervención Coronaria Percutánea , Valor Predictivo de las Pruebas , Resistencia Vascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Infarto del Miocardio sin Elevación del ST/diagnóstico por imagen , Infarto del Miocardio sin Elevación del ST/mortalidad , Infarto del Miocardio sin Elevación del ST/terapia , Infarto del Miocardio sin Elevación del ST/fisiopatología , Anciano , Medición de Riesgo , Estudios Retrospectivos , Intervención Coronaria Percutánea/efectos adversos , Factores de Riesgo , Factores de Tiempo , Diabetes Mellitus/epidemiología , Diabetes Mellitus/diagnóstico , Resultado del Tratamiento , Insuficiencia Cardíaca/fisiopatología , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/diagnóstico , Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/terapia , Insuficiencia Cardíaca/epidemiología , China/epidemiología
14.
BMC Med Educ ; 24(1): 830, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-39090574

RESUMEN

INTRODUCTION: Radiological imaging has played an important role in diagnostic medicine for over a century, though it is known to contribute to dermatological conditions, cataracts, and cancer. The associated risk of harm has led to the introduction of protective regulations around the world. Present-day NHS clinicians are increasingly requesting and relying on diagnostic imaging. Knowledge surrounding the radiation doses of common radiological investigations and the associated risks is imperative, and on a global level has been found to be inadequate. Consequently, there is a need for the formal inclusion of teaching within training programmes. AIMS/OBJECTIVES: This prospective audit aims to establish the knowledge of radiation doses and risks of common radiological investigations of both medical students and referrers within four NHS Health Boards based in the North of Scotland. It also seeks to establish prior teaching and the preference for further educational interventions. AUDIT STANDARD: Referrers should have adequate knowledge of radiation doses and the risks associated with common radiological investigations. AUDIT TARGET: The standard should be achieved by 90% of referrers. METHODS: A 19-question online survey was devised to include subjective and objective questions on ionising radiation awareness, education preference, and respondent demographics, based on RCR (Royal College of Radiologists) audit criteria and previous studies. Data collection was conducted between the 22/02/23 to the 22/03/2023 and the questionnaire was distributed to senior medical students and radiological referrers of different grades within NHS Grampian, NHS Highland, NHS Shetland, and NHS Orkney. A descriptive analysis of the data was undertaken using Microsoft Excel Version 16.71. RESULTS: Two hundred eight questionnaires were completed. 22.11% (n = 46) of the sample population had received no prior teaching on the topic of ionising radiation. Over half of the respondents (51.92%, n = 108) rated the importance of radiation risks as either important or extremely important, with 69.71% (n = 145) of participants rating their perceived knowledge as limited or average. Most correctly identified that a CT scan (n = 203), PET-CT scan (n = 199) and a chest x-ray (n = 196) exposed patients to ionising radiation. A small proportion of the participants incorrectly thought that an MRI scan (n = 21) and an ultrasound scan (n = 2) involved ionising radiation. The results obtained failed to meet the RCR audit target, which states that 90% of doctors should be aware of common radiological doses. It was observed that only 17.79% (n = 37) of survey respondents scored over 50% in the knowledge assessment, with the median knowledge score of the whole cohort being 2.5 out of 9 (27.78%). Respondents who had prior teaching on the topic performed better those who had no prior teaching, with average scores of 3.19 (35.44%) and 2.04 (22.67%) respectively. Senior clinicians performed better when compared to junior clinicians and medical students. CONCLUSION & FUTURE RECOMMENDATIONS: This audit found that the knowledge of radiation risks within the North of Scotland in the selected sample population was insufficient across all levels of the clinical team. Further, continuous education around the topic and future audit opportunities may help to optimise knowledge and training.


Asunto(s)
Conocimientos, Actitudes y Práctica en Salud , Dosis de Radiación , Estudiantes de Medicina , Humanos , Escocia , Estudios Prospectivos , Femenino , Derivación y Consulta , Masculino , Encuestas y Cuestionarios , Adulto , Auditoría Médica
15.
Materials (Basel) ; 17(15)2024 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-39124485

RESUMEN

The low delamination tendency and high damage tolerance of three-dimensional (3D) braided composites highlight their significant potential in handling defects. To enhance the engineering potential of three-dimensional four-directional (3D4d) braided composites and assess the failure mode of hole defects, this study introduces a series of 3D4d braided composites with prefabricated holes, studying their compressive properties and failure mechanisms through experimental and finite element methods. Digital image correlation (DIC) was used to monitor the compressive strain on the surface of materials. Scanning acoustic microscope (SAM) and scanning electron microscopy (SEM) were used to characterize the longitudinal compression failure mode inside the material. A macroscopic model is established, and the porous materials are predicted by using the general braided composite material prediction theory. While reducing the forecast cost, the error is also controlled within 21%. The analysis of failure mechanisms elucidates the damage extension mode, and the porous damage tolerance ability aligns closely with the bearing mode of braided material structure. Different braiding angles will lead to different bearing modes of materials. Under longitudinal compression, the average strength loss of 15° specimens is 38.21%, and that of 30° specimens is 8.1%. The larger the braided angle, the stronger the porous damage tolerance. Different types of prefabricated holes will also affect their mechanical properties and damage tolerance.

16.
JACC Cardiovasc Interv ; 17(16): 1874-1886, 2024 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-39115479

RESUMEN

BACKGROUND: The index of microcirculatory resistance is a reliable measure for evaluating coronary microvasculature, but its prognostic value in patients with non-ST-segment elevation myocardial infarction (NSTEMI) remains unclear. OBJECTIVES: This study aimed to evaluate the prognostic impact of postpercutaneous coronary intervention (PCI) angiography-derived index of microcirculatory resistance (angio-IMR) in patients with NSTEMI. METHODS: The culprit vessel's angio-IMR was measured after PCI in 2,212 NSTEMI patients at 3 sites. The primary endpoint was 2-year major adverse cardiac events (MACEs), defined as a composite of cardiac death, readmission for heart failure, myocardial reinfarction, and target vessel revascularization. RESULTS: The mean post-PCI angio-IMR was 20.63 ± 4.17 in NSTEMI patients. A total of 206 patients were categorized as the high post-PCI angio-IMR group according to maximally selected log-rank statistics. Patients with angio-IMR >25 showed a higher rate of MACEs than those with angio-IMR ≤25 (32.52% vs 9.37%; P < 0.001). Post-PCI angio-IMR >25 was an independent predictor of MACEs (HR: 4.230; 95% CI: 3.151-5.679; P < 0.001) and showed incremental prognostic value compared with conventional risk factors (AUC: 0.774 vs 0.716; P < 0.001; net reclassification index: 0.317; P < 0.001; integrated discrimination improvement: 0.075; P < 0.001). CONCLUSIONS: In patients undergoing PCI for NSTEMI, an increased post-PCI angio-IMR is associated with a higher risk of MACEs. The addition of post-PCI angio-IMR into conventional risk factors significantly improves the ability to reclassify patients and estimate the risk of MACEs. (Angiograph-Derived Index of Microcirculatory Resistance in Patients With Acute Myocardial Infarction; NCT05696379).


Asunto(s)
Angiografía Coronaria , Circulación Coronaria , Microcirculación , Infarto del Miocardio sin Elevación del ST , Intervención Coronaria Percutánea , Valor Predictivo de las Pruebas , Resistencia Vascular , Humanos , Masculino , Femenino , Persona de Mediana Edad , Anciano , Infarto del Miocardio sin Elevación del ST/diagnóstico por imagen , Infarto del Miocardio sin Elevación del ST/terapia , Infarto del Miocardio sin Elevación del ST/fisiopatología , Infarto del Miocardio sin Elevación del ST/mortalidad , Intervención Coronaria Percutánea/efectos adversos , Factores de Riesgo , Resultado del Tratamiento , Medición de Riesgo , Factores de Tiempo , Recurrencia , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Readmisión del Paciente , China
17.
Adv Sci (Weinh) ; : e2406008, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39136135

RESUMEN

Designing high-entropy oxyhydroxides (HEOs) electrocatalysts with controlled nanostructures is vital for efficient and stable water-splitting electrocatalysts. Herein, a novel HEOs material (FeCoNiWCuOOH@Cu) containing five non-noble metal elements derived by electrodeposition on a 3D double-continuous porous Cu support is created. This support, prepared via the liquid metal dealloying method, offers a high specific surface area and rapid mass/charge transfer channels. The resulting high-entropy FeCoNiWCuOOH nanosheets provide a dense distribution of active sites. The heterostructure between Cu skeletons and FeCoNiWCuOOH nanosheets enhances mass transfer, electronic structure coupling, and overall structural stability, leading to excellent activities in the oxygen evolution reaction (OER), hydrogen evolution reaction (HER), and water splitting reaction. At 10 mA cm-2, the overpotentials for OER, HER, and water splitting in 1.0 m KOH solution are 200, 18, and 1.40 V, respectively, outperforming most current electrocatalysts. The catalytic performance remains stable even after operating at 300 mA cm-2 for 100, 100, and over 1000 h, correspondingly. This material has potential applications in integrated hydrogen energy systems. More importantly, density functional theory (DFT) calculations demonstrate the synergy of the five elements in enhancing water-splitting activity. This work offers valuable insights for designing industrial water electrolysis systems.

18.
J Chem Theory Comput ; 20(15): 6971-6979, 2024 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-39088397

RESUMEN

Cation ordering in multication perovskites is related to many important material properties and performances, but computational determination of the cation ordering remains a major challenge. Here, we propose a new computational approach by introducing a machine learning recommender system into the basin-hopping framework (RBH) for optimizing cation ordering. Taking the electrocatalyst Ba0.5Sr0.5Co0.8Fe0.2O3 (BSCF5582) as a showcase example, we found that the efficiency of RBH in identifying low-energy configurations outperforms the methods of cluster expansion and conventional basin-hopping. The RBH results revealed that the BSCF5582 catalyst tended to have a layered ordering of A-site cations and disordered B-site cations both in bulk and on the surfaces. Further, on the A-site-terminated surface, we found the segregation of large Ba atoms. Similarly, on the A-site- terminated surface of the recently developed Cs0.2Sr0.8Co0.4Fe0.6O3 (CSCF2846) catalyst, layered ordering at the A-site and surface enrichment of large Cs atoms were also found. The layered ordering was robust against thermal effects, as found from molecular dynamics simulations at 800 K. This work provides a new approach for thermodynamic global optimization of chemical ordering in multicomponent materials.

19.
Sci Rep ; 14(1): 18870, 2024 08 14.
Artículo en Inglés | MEDLINE | ID: mdl-39143137

RESUMEN

The characteristics of dopamine self-polymerization were used to cover the nano-titanium dioxide (TiO2) surface and produce nano-titanium dioxide-polydopamine (TiO2-PDA). The reducing nature of dopamine was then used to reduce silver nitrate to silver elemental particles on the modified nano-titanium dioxide: The resulting TiO2-PDA-Ag nanoparticles were used as antimicrobial agents. Finally, the antibacterial agent was mixed with silicone to obtain an antibacterial silicone composite material. The composition and structure of antibacterial agents were analyzed by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron energy spectroscopy, and X-ray diffraction. Microscopy and the antibacterial properties of the silicone antibacterial composites were studied as well. The TiO2-PDA-Ag antimicrobial agent had good dispersion versus nano-TiO2. The three were strongly combined with obvious characteristic peaks. The antibacterial agents were evenly dispersed in silicone, and the silicone composite has excellent antibacterial properties. Bacillus subtilis (B. subtilis) adhesion was reduced from 246 × 104 cfu/cm2 to 2 × 104 cfu/cm2, and colibacillus (E. coli) reduced from 228 × 104 cfu/cm2 leading to bacteria-free adhesion.


Asunto(s)
Bacillus subtilis , Escherichia coli , Siliconas , Plata , Titanio , Titanio/química , Titanio/farmacología , Siliconas/química , Plata/química , Plata/farmacología , Escherichia coli/efectos de los fármacos , Bacillus subtilis/efectos de los fármacos , Nanopartículas del Metal/química , Antibacterianos/farmacología , Antibacterianos/química , Antiinfecciosos/farmacología , Antiinfecciosos/química , Polímeros/química , Polímeros/farmacología , Difracción de Rayos X , Pruebas de Sensibilidad Microbiana , Adhesión Bacteriana/efectos de los fármacos , Indoles
20.
Microorganisms ; 12(8)2024 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-39203480

RESUMEN

Wheat production is intrinsically linked to global food security. However, wheat cultivation is constrained by the progressive degradation of soil conditions resulting from the continuous application of fertilizers. This study aimed to examine the effects of deep tillage on rhizosphere soil microbial communities and their potential role in improving soil quality, given that the specific mechanisms driving these observed benefits remain unclear. Soil fertility in this research was evaluated through the analysis of various soil parameters, including total nitrogen, total phosphorus, total potassium, available phosphorus, and available potassium, among others. The high-throughput sequencing technique was utilized to examine the rhizosphere microbial community associated with deep tillage wheat. The findings indicated that deep tillage cultivation of wheat led to reduced fertility levels in the 0-20 cm soil layer in comparison with non-deep tillage cultivation. A sequencing analysis indicated that Acidobacteria and Proteobacteria are the dominant bacterial phyla, with Proteobacteria being significantly more abundant in the deep tillage group. The dominant fungal phyla identified were Ascomycota, Mortierellomycota, and Basidiomycota. Among bacterial genera, Arthrobacter, Bacillus, and Nocardioides were predominant, with Arthrobacter showing a significantly higher presence in the deep tillage group. The predominant fungal genera included Mortierella, Alternaria, Schizothecium, and Cladosporium. Deep tillage cultivation has the potential to enhance soil quality and boost crop productivity through the modulation of soil microbial community structure.

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