Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 502
Filtrar
1.
J Org Chem ; 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38940361

RESUMO

A palladium-catalyzed/copper-mediated cross-coupling of S-pyrimidinyl thioesters with arylboronic acids to yield biaryls is described. The reaction is likely to proceed via cleavage of the S-C(O) bond and subsequent release of CO, rather than via cleavage of the S-C(pyrimidine) bond and release of SCO, as supported by the results of both experimental and computational studies. The investigation of the reaction scope with various S-pyrimidinyl thioesters and arylboronic acids showed that the reaction is significantly affected by the substituent of the thioester and the presence of a chelatable ortho substituent was found to increase reaction efficiency.

3.
Clin Orthop Surg ; 16(3): 374-381, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38827757

RESUMO

Background: Hemiarthroplasty is frequently used to treat displaced femoral neck fractures in elderly patients, but it has a higher risk of postoperative dislocation. We introduced the posterior approach and inferior capsulotomy (PAICO) to enhance joint stability after bipolar hemiarthroplasty for femoral neck fracture. We evaluated whether the PAICO would have a lower dislocation rate than the conventional posterior approach with superior capsulotomy. Methods: From January 2021 to December 2021, we prospectively recruited 25 patients (25 hips) aged 50 years or older who underwent bipolar hemiarthroplasty for femoral neck fractures due to low-energy trauma as the PAICO group. We compared the PAICO group with a historical control group who had undergone hemiarthroplasty in 7 institutes between 2010 and 2020. The primary endpoint was dislocation within 1 year after the surgery. We compared data from the PAICO group with the data from the historical control group from the Korean Hip Fracture Registry which was carried out in South Korea. Results: A total of 25 patients (25 hips) were enrolled in the present study; 3,477 patients (3,571 hips) who underwent bipolar hemiarthroplasty were reviewed as the historical control group. In the PAICO group, we observed no dislocation, whereas the dislocation rate in the control group was 1.3%. Conclusions: In patients with displaced femoral neck fractures, the PAICO approach demonstrated comparable results in operation time and complication rates when compared to bipolar hemiarthroplasty using superior capsulotomy. Notably, there were no observed cases of dislocation among patients who underwent the PAICO approach. We recommend this PAICO approach to surgeons using the posterior approach, hoping to prevent dislocation in bipolar hemiarthroplasty.


Assuntos
Fraturas do Colo Femoral , Hemiartroplastia , Humanos , Fraturas do Colo Femoral/cirurgia , Hemiartroplastia/métodos , Feminino , Masculino , Idoso , Pessoa de Meia-Idade , Estudos Prospectivos , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/epidemiologia , Cápsula Articular/cirurgia
4.
BMC Complement Med Ther ; 24(1): 217, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38844985

RESUMO

BACKGROUND: Atopic dermatitis (AD) is a chronic inflammatory condition characterized by the accumulation of reactive oxygen species and the expression of inflammatory factors. Regarding its anti-atopic activity, numerous traditional medicinal materials and secondary metabolic products play pivotal roles in modulating the associated mechanisms. METHODS: This study aimed to utilize Salvia miltiorrhiza Bunge (SMB) as an anti-AD source. In-vitro activity assessments and qualitative and quantitative analyses using UPLC-TQ-MS/MS and HPLC-DAD were conducted in two cultivars ('Dasan' and 'Kosan'). Statistical analysis indicated that the profiles of their secondary metabolites contribute significantly to their pharmacological properties. Consequently, bio-guided fractionation was undertaken to figure out the distinct roles of the secondary metabolites present in SMB. RESULTS: Comparative study of two cultivars indicated that 'Dasan', having higher salvianolic acid A and B, exhibited stronger antioxidant and anti-inflammatory activities. Meanwhile, 'Kosan', containing higher tanshinones, showed higher alleviating activities on anti-AD related genes in mRNA levels. Additionally, performed bio-guided fractionation re-confirmed that the hydrophilic compounds of SMB can prevent AD by inhibiting accumulation of ROS and suppressing inflammatory factors and the lipophilic components can directly inhibit AD. CONCLUSIONS: SMB was revealed as a good source for anti-AD activity. Several bioactive compounds were identified from the UPLC-TQ-MS/MS and different compounds content was linked to biological activities. Characterization of these compounds may be helpful to understand differential role of secondary metabolites from SMB on alleviation of AD.


Assuntos
Anti-Inflamatórios , Dermatite Atópica , Extratos Vegetais , Salvia miltiorrhiza , Salvia miltiorrhiza/química , Dermatite Atópica/tratamento farmacológico , Extratos Vegetais/farmacologia , Humanos , Anti-Inflamatórios/farmacologia , Espectrometria de Massas em Tandem , Cromatografia Líquida de Alta Pressão , Antioxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo
5.
Restor Dent Endod ; 49(2): e20, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38841379

RESUMO

Objectives: This study investigated the nanoleakage of root canal obturations using calcium silicate-based sealer according to different drying methods. Materials and Methods: Fifty-two extracted mandibular premolars with a single root canal and straight root were selected for this study. After canal preparation with a nickel-titanium rotary file system, the specimens were randomly divided into 4 groups according to canal drying methods (1: complete drying, 2: blot drying/distilled water, 3: blot drying/NaOCl, 4: aspiration only). The root canals were obturated using a single-cone filling technique with a calcium silicate-based sealer. Nanoleakage was evaluated using a nanoflow device after 24 hours, 1 week, and 1 month. Data were collected twice per second at the nanoscale and measured in nanoliters per second. Data were statistically analyzed using the Kruskal-Wallis and Mann-Whitney U-tests (p < 0.05). Results: The mean flow rate measured after 24 hours showed the highest value among the time periods in all groups. However, the difference in the flow rate between 1 week and 1 month was not significant. The mean flow rate of the complete drying group was the highest at all time points. After 1 month, the mean flow rate in the blot drying group and the aspiration group was not significantly different. Conclusions: Within the limitations of this study, the canal drying method had a significant effect on leakage and sealing ability in root canal obturations using a calcium silicate-based sealer. Thus, a proper drying procedure is critical in endodontic treatment.

6.
Cleft Palate Craniofac J ; : 10556656241261846, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38881285

RESUMO

OBJECTIVE: Narrowing of the palatal cleft is often observed in infants with Robin sequence (RS) treated with the Stanford Orthodontic Airway Plate treatment (SOAP) even though SOAP is utilized primarily to establish airway patency. The current study quantified dimensional changes of the cleft palate (CP) in infants with RS treated with SOAP. DESIGN: A retrospective chart review. PATIENTS: Infants with RS and CP who completed SOAP and had maxillary arch models at both pre- and post-treatment time points at a single tertiary referral hospital between September 2019 and July 2023. SETTING AND OUTCOME MEASURE: Maxillary arch models were measured and analyzed using Bivariate statistical analysis. RESULTS: Seventeen infants were included in the study. The median age (min, max) was 6.7 weeks (1.1, 21.9) at pre-treatment and 26.6 weeks (18.7, 37.0) at post-treatment. The median Obstructive Apnea Hypopnea Index was 36.2 events/hour (8.1, 103.1) at pre-treatment and 4.1 events/hour (1.9, 8.6) at post-treatment. The pre-treatment width of CP decreased by an average (± standard diviation) of 6.37 mm (± 3.55, p < 0.001) at post-treatment. The ratio of the posterior cleft width to the total maxillary arch width decreased from 40% (± 9.1) at pre-treatment to 22% (± 11) at post-treatment (p < 0.001). CONCLUSION: The dimensions of CP reduced significantly during SOAP in infants with RS and CP treated for their severe upper airway obstruction. The findings highlight a potential benefit of SOAP that may contribute favorably to the palate repair surgery.

7.
Sensors (Basel) ; 24(9)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38732859

RESUMO

Vehicular ad hoc networks (VANETs) use multiple channels to communicate using wireless access in vehicular environment (WAVE) standards to provide a variety of vehicle-related applications. The current IEEE 802.11p WAVE communication channel structure is composed of one control channel (CCH) and several service channels (SCHs). SCHs are used for non-safety data transmission, while the CCH is used for broadcasting beacons, control, and safety. WAVE devices transmit data that alternate between CCHs and SCHs, and each channel is active for a duration called the CCH interval (CCHI) and SCH interval (SCHI), respectively. Currently, both intervals are fixed at 50 ms. However, fixed-length intervals cannot effectively respond to dynamically changing traffic loads. Additionally, when many vehicles are simultaneously using the limited channel resources for data transmission, the network performance significantly degrades due to numerous packet collisions. Herein, we propose an adaptive resource allocation technique for efficient data transmission. The technique dynamically adjusts the SCHI and CCHI to improve network performance. Moreover, to reduce data collisions and optimize the network's backoff distribution, the proposed scheme applies reinforcement learning (RL) to provide an intelligent channel access algorithm. The simulation results demonstrate that the proposed scheme can ensure high throughputs and low transmission delays.

8.
J Korean Assoc Oral Maxillofac Surg ; 50(2): 103-109, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38693133

RESUMO

Teriparatide has been effective in treating people diagnosed with medication-related osteonecrosis of the jaw (MRONJ). However, its efficacy is not well established to be accepted as a standard of care. The objective of this paper was to investigate the efficacy of recombinant human parathyroid hormone for the treatment of MRONJ. We report three cases of MRONJ patients with osteoporosis as the primary disease who were treated with a teriparatide agent along with other adjunctive measures. Each patient was administered a teriparatide injection subcutaneously for 16 weeks, 36 weeks, or 60 weeks. Surgical intervention including partial resection, sequestrectomy, decortication, and saucerization took place during the teriparatide administration. Complete lesion resolution was identified clinically and radiographically in all three patients. In patients diagnosed with MRONJ, teriparatide therapy is an efficacious and safe therapeutic option to improve healing of bone lesions. These findings demonstrate that teriparatide in combination with another therapy, especially bone morphogenetic protein, platelet-rich fibrin, or antibiotic therapy, can be an effective protocol for MRONJ.

9.
Medicina (Kaunas) ; 60(5)2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38792863

RESUMO

Introduction: Basicervical femoral neck fracture (FNF) is an uncommon type of femoral neck fracture and is associated with an increased risk of fixation failure due to its inherent instability. The purpose of this study was to compare the surgical parameters and reoperation rate between the use of a multiple cannulated screw (MCS) and fixed angle device (FAD) in treating basicervical FNFs. Methods: We retrospectively reviewed the records of 885 patients who underwent internal fixation between May 2004 and August 2019 to determine basicervical FNF with at least 12 months of follow-up. Among the identified 77 patients with basicervical FNF, 17 patients who underwent multiple cannulated screw (MCS) fixation and 36 patients who underwent fixed angle device (FAD) fixation were included. We compared the rates of fracture-site collapse and reoperations according to the fixation device. Results: Among the 53 patients with basicervical FNF, 13 patients (24.5%) sustained surgical complications (8 collapses of fracture site and 5 reoperations). The reoperation rate in the MCS group was significantly higher than that in the FAD group (23.5% vs. 2.8%, p = 0.016), without any significant difference in the collapse of the fracture site (11.8% vs. 16.7%, p = 0.642). Conclusions: Although basicervical FNF was rare among hip fractures, fracture site collapse was prevalent and prone to fixation failure. Surgeons should keep this in mind, and consider FAD for basicervical FNF.


Assuntos
Parafusos Ósseos , Fraturas do Colo Femoral , Fixação Interna de Fraturas , Humanos , Fraturas do Colo Femoral/cirurgia , Feminino , Masculino , Estudos Retrospectivos , Fixação Interna de Fraturas/métodos , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/estatística & dados numéricos , Idoso , Pessoa de Meia-Idade , Resultado do Tratamento , Reoperação/estatística & dados numéricos , Idoso de 80 Anos ou mais , Complicações Pós-Operatórias/epidemiologia
10.
Cell Mol Immunol ; 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38806623

RESUMO

Type 2 innate lymphoid cells (ILC2s) have emerged as key regulators of the immune response in renal inflammatory diseases such as lupus nephritis. However, the mechanisms underlying ILC2 adhesion and migration in the kidney remain poorly understood. Here, we revealed the critical role of integrin α4ß7 in mediating renal ILC2 adhesion and function. We found that integrin α4ß7 enables the retention of ILC2s in the kidney by binding to VCAM-1, E-cadherin, or fibronectin on structural cells. Moreover, integrin α4ß7 knockdown reduced the production of the reparative cytokine amphiregulin (Areg) by ILC2s. In lupus nephritis, TLR7/9 signaling within the kidney microenvironment downregulates integrin α4ß7 expression, leading to decreased Areg production and promoting the egress of ILC2s. Notably, IL-33 treatment upregulated integrin α4ß7 and Areg expression in ILC2s, thereby enhancing survival and reducing inflammation in lupus nephritis. Together, these findings highlight the potential of targeting ILC2 adhesion as a therapeutic strategy for autoimmune kidney diseases.

11.
Polymers (Basel) ; 16(8)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675055

RESUMO

Three-dimensional microextrusion bioprinting technology uses pneumatics, pistons, or screws to transfer and extrude bioinks containing biomaterials and cells to print biological tissues and organs. Computational fluid dynamics (CFD) analysis can simulate the flow characteristics of bioinks in a control volume, and the effect on cell viability can be predicted by calculating the physical quantities. In this study, we developed an analysis system to predict the effect of a screw-based dispenser system (SDS) on cell viability in bioinks through rheological and CFD analyses. Furthermore, carboxymethylcellulose/alginate-based bioinks were used for the empirical evaluation of high-viscous bioinks. The viscosity of bioinks was determined by rheological measurement, and the viscosity coefficient for the CFD analysis was derived from a correlation equation by non-linear regression analysis. The mass flow rate derived from the analysis was successfully validated by comparison with that from the empirical evaluation. Finally, the cell viability was confirmed after bioprinting with bioinks containing C2C12 cells, suggesting that the developed SDS may be suitable for application in the field of bioengineering. Consequently, the developed bioink analysis system is applicable to a wide range of systems and materials, contributing to time and cost savings in the bioengineering industry.

12.
Sci Rep ; 14(1): 8723, 2024 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-38622273

RESUMO

The Alpha stent is an intracranial closed-cell stent with a unique mesh design to enhance wall apposition. It recently underwent structural modifications to facilitate easier stent deployment. This study aimed to evaluate the safety and efficacy of stent-assisted coil embolization for unruptured intracranial aneurysms using the Alpha stent. Between January 2021 and November 2021, 35 adult patients with 35 unruptured intracranial aneurysms in the distal internal carotid artery were prospectively enrolled. For efficacy outcomes, magnetic resonance angiography at the 6-month follow-up was evaluated using the Raymond-Roy occlusion classification (RROC). The safety outcome evaluated the occurrence of symptomatic procedure-related neurological complications up to 6 months postoperatively. Technical success was achieved in 34/35 (97.1%). Six months postoperatively, aneurysm occlusion showed RROC I in 32/35 (91.4%) and RROC II in 3/35 (8.6%) patients. Procedure-related neurologic complications occurred in one patient (2.9%) who experienced hemiparesis due to acute lacunar infarction, which resulted in a 6-month mRS score of 1. The Alpha stent demonstrated excellent efficacy and safety outcomes in stent-assisted coil embolization of unruptured distal ICA aneurysms. The recent structural modifications allowed for easier stent delivery and deployment.Clinical trial registration number: KCT0005841; registration date: 28/01/2021.


Assuntos
Embolização Terapêutica , Aneurisma Intracraniano , Adulto , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Resultado do Tratamento , Embolização Terapêutica/efeitos adversos , Embolização Terapêutica/métodos , Stents/efeitos adversos , Prótese Vascular , Angiografia Cerebral/métodos , Estudos Retrospectivos
13.
Korean J Radiol ; 25(5): 481-492, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38627873

RESUMO

OBJECTIVE: To evaluate the clinical and imaging characteristics of SARS-CoV-2 breakthrough infection in hospitalized immunocompromised patients in comparison with immunocompetent patients. MATERIALS AND METHODS: This retrospective study analyzed consecutive adult patients hospitalized for COVID-19 who received at least one dose of the SARS-CoV-2 vaccine at two academic medical centers between June 2021 and December 2022. Immunocompromised patients (with active solid organ cancer, active hematologic cancer, active immune-mediated inflammatory disease, status post solid organ transplantation, or acquired immune deficiency syndrome) were compared with immunocompetent patients. Multivariable logistic regression analysis was performed to evaluate the effect of immune status on severe clinical outcomes (in-hospital death, mechanical ventilation, or intensive care unit admission), severe radiologic pneumonia (≥ 25% of lung involvement), and typical CT pneumonia. RESULTS: Of 2218 patients (mean age, 69.5 ± 16.1 years), 274 (12.4%), and 1944 (87.6%) were immunocompromised an immunocompetent, respectively. Patients with active solid organ cancer and patients status post solid organ transplantation had significantly higher risks for severe clinical outcomes (adjusted odds ratio = 1.58 [95% confidence interval {CI}, 1.01-2.47], P = 0.042; and 3.12 [95% CI, 1.47-6.60], P = 0.003, respectively). Patient status post solid organ transplantation and patients with active hematologic cancer were associated with increased risks for severe pneumonia based on chest radiographs (2.96 [95% CI, 1.54-5.67], P = 0.001; and 2.87 [95% CI, 1.50-5.49], P = 0.001, respectively) and for typical CT pneumonia (9.03 [95% CI, 2.49-32.66], P < 0.001; and 4.18 [95% CI, 1.70-10.25], P = 0.002, respectively). CONCLUSION: Immunocompromised patients with COVID-19 breakthrough infection showed an increased risk of severe clinical outcome, severe pneumonia based on chest radiographs, and typical CT pneumonia. In particular, patients status post solid organ transplantation was specifically found to be associated with a higher risk of all three outcomes than hospitalized immunocompetent patients.


Assuntos
COVID-19 , Hospedeiro Imunocomprometido , SARS-CoV-2 , Tomografia Computadorizada por Raios X , Humanos , COVID-19/diagnóstico por imagem , Masculino , Feminino , Estudos Retrospectivos , Idoso , Tomografia Computadorizada por Raios X/métodos , Pessoa de Meia-Idade , Hospitalização , Idoso de 80 Anos ou mais , Vacinas contra COVID-19 , Pulmão/diagnóstico por imagem , Infecções Irruptivas
14.
Bioengineering (Basel) ; 11(4)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38671749

RESUMO

Templating is essential in hip arthroplasty preparation, facilitating implant size prediction and surgical rehearsal. It ensures the selection of suitable implants according to patient anatomy and disease, aiming to minimize post-operative complications. Various templating methods exist, including traditional acetate templating on both analog and digital images, alongside digital templating on digital images, which is categorized into 2D and 3D approaches. Despite the popularity of acetate templating on digital images, challenges such as the requirement for physical templates and result preservation persist. To address these limitations, digital templating with software like OrthoSize and Orthoview has been suggested, although not universally accessible. This technical note advocates for Microsoft PowerPoint as an effective alternative for 2D digital templating, highlighting its user-friendly features for image manipulation without needing specialized software. The described method involves scanning acetate templates, adjusting the images in PowerPoint 365 for size, position, and calibration on patient radiographs, and demonstrating reliability through preliminary assessments, with intraclass correlation coefficient (ICC) values indicating a high level of agreement for cup and stem size (ICC = 0.860, 0.841, respectively) but moderate for neck length (ICC = 0.592). We have introduced a method for performing 2D digital templating in the clinical field without the need for specialized software dedicated to digital templating. We believe this method significantly improves the accessibility to 2D digital templating, which was previously limited by the need for digital templating software. Additionally, it enables surgeons to easily establish arthroplasty plans and share them, overcoming the limitations of acetate templates.

15.
Diseases ; 12(4)2024 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-38667523

RESUMO

There have been previous studies conducted to predict postoperative lung function with pulmonary function tests (PFTs). Computing tomography (CT) can quantitatively measure small airway walls' thickness, lung volume, pulmonary vessel volume, and emphysema area, which reflect the severity of respiratory diseases. These measurements are considered imaging biomarkers. This study aimed to predict postoperative lung function with imaging biomarkers. A retrospective analysis of 79 patients with lung cancer who had undergone lung surgery was completed. Postoperative lung function measured by forced expiratory volume in one second (FEV1) was defined as an outcome. Preoperative clinico-pathological parameters and imaging biomarkers representing airway walls' thickness, severity of emphysema, total lung volume, and pulmonary vessel volume were measured quantitatively in chest CT by an automated segmentation software, AVIEW COPD. Pi1 was defined as the first percentile along the histogram of lung attenuation that represents the degree of emphysema. Wafw was defined as the airway thickness, which was calculated by the full-width at half-maximum method. Logistic and linear regressions were used to assess these variables. If the actual postoperative FEV1 was higher than the postoperative FEV1 projected by a formula, the group was considered to be preserved. Among the 79 patients, 16 of the patients were grouped as a non-preserved group, and 63 of them were grouped as a preserved group. The patients in the preserved FEV1 group had a higher vessel volume than the non-preserved group. Pi1 and Wafw were independent predictors of postoperative lung function. Imaging biomarkers can be considered significant variables in predicting postoperative lung function in patients with lung cancer.

16.
Front Psychiatry ; 15: 1348319, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38666089

RESUMO

Background: Depression and anxiety are prevalent mental health concerns among children and adolescents. The application of conventional assessment methods, such as survey questionnaires to children, may lead to self-reporting issues. Digital biomarkers provide extensive data, reducing bias in mental health self-reporting, and significantly influence patient screening. Our primary objectives were to accurately assess children's mental health and to investigate the feasibility of using various digital biomarkers. Methods: This study included a total of 54 boys and girls aged between 7 to 11 years. Each participant's mental state was assessed using the Depression, Anxiety, and Stress Scale. Subsequently, the subjects participated in digital biomarker collection tasks. Heart rate variability (HRV) data were collected using a camera sensor. Eye-tracking data were collected through tasks displaying emotion-face stimuli. Voice data were obtained by recording the participants' voices while they engaged in free speech and description tasks. Results: Depressive symptoms were positively correlated with low frequency (LF, 0.04-0.15 Hz of HRV) in HRV and negatively associated with eye-tracking variables. Anxiety symptoms had a negative correlation with high frequency (HF, 0.15-0.40 Hz of HRV) in HRV and a positive association with LF/HF. Regarding stress, eye-tracking variables indicated a positive correlation, while pNN50, which represents the proportion of NN50 (the number of pairs of successive R-R intervals differing by more than 50 milliseconds) divided by the total number of NN (R-R) intervals, exhibited a negative association. Variables identified for childhood depression included LF and the total time spent looking at a sad face. Those variables recognized for anxiety were LF/HF, heart rate (HR), and pNN50. For childhood stress, HF, LF, and Jitter showed different correlation patterns between the two grade groups. Discussion: We examined the potential of multimodal biomarkers in children, identifying features linked to childhood depression, particularly LF and the Sad.TF:time. Anxiety was most effectively explained by HRV features. To explore reasons for non-replication of previous studies, we categorized participants by elementary school grades into lower grades (1st, 2nd, 3rd) and upper grades (4th, 5th, 6th). Conclusion: This study confirmed the potential use of multimodal digital biomarkers for children's mental health screening, serving as foundational research.

17.
Nano Lett ; 24(14): 4224-4232, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38557115

RESUMO

In this study, we identify the local structures of ex-solved nanoparticles using machine-learned potentials (MLPs). We develop a method for training machine-learned potentials by sampling local structures of heterointerface configurations as a training set with its efficacy tested on the Ni/MgO system, illustrating that the error in interface energy is only 0.004 eV/Å2. Using the developed scheme, we train an MLP for the Ni/La0.5Ca0.5TiO3 ex-solution system and identify the local structures for both exo- and endo-type particles. The established model aligns well with the experimental observations, accurately predicting a nucleation size of 0.45 nm. Lastly, the density functional theory calculations on the established atomistic model verify that the kinetic barrier for the dry reforming of methane are substantially reduced by 0.49 eV on the ex-solved catalysts compared to that on the impregnated catalysts. Our findings offer insights into the local structures, growth mechanisms, and underlying origin of the catalytic properties of ex-solved nanoparticles.

18.
World Neurosurg ; 186: 87-94, 2024 06.
Artigo em Inglês | MEDLINE | ID: mdl-38522785

RESUMO

BACKGROUND: Trigeminal neuralgia (TN) is a debilitating condition characterized by sudden, excruciating facial pain due to neurovascular compression of the trigeminal nerve. Stent deployment can change the course of the superior cerebellar artery upwards, possibly releasing the root entry zone of the trigeminal nerve. We developed a novel stent, the Transform stent, for TN treatment, and evaluated its mechanical properties using benchtop and in vitro hemocompatibility tests. METHODS: We compared the performance of Transform and Enterprise stents in treating TN because they share similar self-expanding closed-cell features in the manufacturing process, are derived from nitinol tubes, and are fabricated through a laser-cutting process, but also because only the safety of Enterprise stents deployed in intracranial arteries has been reported clinically. All benchtop measurements, including radial force, trackability, bending stiffness, and conformability, were performed thrice for each stent model, and their average values are presented. RESULTS: Transform stents showed higher radial forces in vessels of diameters ranging from 1.0 mm than Enterprise stents. The trackability of the Transform stent was better than that of the Enterprise stent in a neurovascular model. Bending stiffness was stronger in the Transform stent whereas conformability was superior in the Enterprise stent. No significant thrombogenic issues were observed in the in vitro hemocompatibility tests. CONCLUSIONS: This study demonstrated the Transform stent as a potential option and paved the way for innovative endovascular approaches for the future TN treatment. Namely, the study confirmed that the characteristics of Transform stents at benchtop and in vitro evaluations may be used as a first step for studies such as in vivo pre- and clinical studies.


Assuntos
Stents , Neuralgia do Trigêmeo , Neuralgia do Trigêmeo/cirurgia , Humanos , Ligas , Teste de Materiais , Desenho de Prótese
19.
J Med Internet Res ; 26: e56417, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38509662

RESUMO

BACKGROUND: Dysarthria is a common poststroke speech disorder affecting communication and psychological well-being. Traditional speech therapy is effective but often poses challenges in terms of accessibility and patient adherence. Emerging smartphone-based therapies may offer promising alternatives for the treatment of poststroke dysarthria. OBJECTIVE: This study aimed to assess the efficacy and feasibility of smartphone-based speech therapy for improving speech intelligibility in patients with acute and early subacute poststroke dysarthria. This study also explored the impact of the intervention on psychological well-being, user experience, and overall feasibility in a clinical setting. METHODS: Participants were divided into 2 groups for this randomized, evaluator-blinded trial. The intervention group used a smartphone-based speech therapy app for 1 hour per day, 5 days per week, for 4 weeks, with guideline-based standard stroke care. The control group received standard guideline-based stroke care and rehabilitation. Speech intelligibility, psychological well-being, quality of life, and user acceptance were assessed using repeated measures ANOVA. RESULTS: In this study, 40 patients with poststroke dysarthria were enrolled, 32 of whom completed the trial (16 in each group). The intervention group showed significant improvements in speech intelligibility compared with the control group. This was evidenced by improvements from baseline (F1,30=34.35; P<.001), between-group differences (F1,30=6.18; P=.02), and notable time-by-group interactions (F1,30=6.91; P=.01). Regarding secondary outcomes, the intervention led to improvements in the percentage of correct consonants over time (F1,30=5.57; P=.03). In addition, significant reductions were noted in the severity of dysarthria in the intervention group over time (F1,30=21.18; P<.001), with a pronounced group effect (F1,30=5.52; P=.03) and time-by-group interaction (F1,30=5.29; P=.03). Regarding quality of life, significant improvements were observed as measured by the EQ-5D-3L questionnaire (F1,30=13.25; P<.001) and EQ-VAS (F1,30=7.74; P=.009) over time. The adherence rate to the smartphone-based app was 64%, with over half of the participants completing all the sessions. The usability of the app was rated high (system usability score 80.78). In addition, the intervention group reported increased self-efficacy in using the app compared with the control group (F1,30=10.81; P=.003). CONCLUSIONS: The smartphone-based speech therapy app significantly improved speech intelligibility, articulation, and quality of life in patients with poststroke dysarthria. These findings indicate that smartphone-based speech therapy can be a useful assistant device in the management of poststroke dysarthria, particularly in the acute and early subacute stroke stages. TRIAL REGISTRATION: ClinicalTrials.gov NCT05146765; https://clinicaltrials.gov/ct2/show/NCT05146765.


Assuntos
Disartria , Estudos de Viabilidade , Smartphone , Fonoterapia , Acidente Vascular Cerebral , Humanos , Disartria/terapia , Disartria/etiologia , Fonoterapia/métodos , Masculino , Feminino , Projetos Piloto , Pessoa de Meia-Idade , Acidente Vascular Cerebral/complicações , Idoso , Qualidade de Vida , Reabilitação do Acidente Vascular Cerebral/métodos , Aplicativos Móveis , Resultado do Tratamento
20.
ACS Nano ; 18(11): 8180-8189, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38450652

RESUMO

Polymer particles capable of dynamic shape changes in response to light have received substantial attention in the development of intelligent multifunctional materials. In this study, we develop a light-responsive block copolymer (BCP) particle system that exhibits fast and reversible shape and color transitions. The key molecular design is the integration of spiropyran photoacid (SPPA) molecules into the BCP particle system, which enables fast and dynamic transformations of polystyrene-b-poly(4-vinylpyridine) (PS-b-P4VP) particles in response to light. The SPPA photoisomerization, induced by 420 nm light irradiation, lowers the pH of the aqueous surroundings from 5.5 to 3.3. The protonated P4VP block substantially increases in domain size from 14 to 39 nm, resulting in significant elongation of the BCP particles (i.e., an increase in the aspect ratio (AR) of the particles from 1.8 to 3.4). Moreover, SPPA adsorbed onto the P4VP surface induces significant changes in the luminescent properties of the BCP particles via photoisomerization of SPPA. Notably, the BCP particles undergo fast, dynamic shape and color transitions within a period of 10 min, maintaining high reversibility over multiple light exposures. Functional dyes are selectively incorporated into different domains of the light-responsive BCP particles to achieve different ranges of color responses. Thus, this study showcases a light-responsive hydrogel display capable of reversible and multicolor photopatterning.

SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...