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1.
Med Biol Eng Comput ; 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38558351

RESUMO

Unplanned readmission after primary total knee arthroplasty (TKA) costs an average of US $39,000 per episode and negatively impacts patient outcomes. Although predictive machine learning (ML) models show promise for risk stratification in specific populations, existing studies do not address model generalizability. This study aimed to establish the generalizability of previous institutionally developed ML models to predict 30-day readmission following primary TKA using a national database. Data from 424,354 patients from the ACS-NSQIP database was used to develop and validate four ML models to predict 30-day readmission risk after primary TKA. Individual model performance was assessed and compared based on discrimination, accuracy, calibration, and clinical utility. Length of stay (> 2.5 days), body mass index (BMI) (> 33.21 kg/m2), and operation time (> 93 min) were important determinants of 30-day readmission. All ML models demonstrated equally good accuracy, calibration, and discriminatory ability (Brier score, ANN = RF = HGB = NEPLR = 0.03; ANN, slope = 0.90, intercept = - 0.11; RF, slope = 0.93, intercept = - 0.12; HGB, slope = 0.90, intercept = - 0.12; NEPLR, slope = 0.77, intercept = 0.01; AUCANN = AUCRF = AUCHGB = AUCNEPLR = 0.78). This study validates the generalizability of four previously developed ML algorithms in predicting readmission risk in patients undergoing TKA and offers surgeons an opportunity to reduce readmissions by optimizing discharge planning, BMI, and surgical efficiency.

2.
Materials (Basel) ; 17(3)2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38591389

RESUMO

Specimens made of various materials with different geometric features were investigated to predict the failure loads using the recently proposed criterion comprised of both stress and stress gradient conditions. The notch types were cracks and holes, and the materials were brittle, ductile, isotropic, orthotropic, or fibrous composites. The predicted failure stresses or loads were compared to experimental results, and both experimental and theoretically predicted results agreed well for all the different cases. This suggests that the stress and stress-gradient-based failure criterion is both versatile and accurate in predicting the failure of various materials and geometric features.

3.
Sports Biomech ; : 1-15, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38623642

RESUMO

Vertical and horizontal rhythms are crucial aspects of a dynamic golf swing, and the two-step swing drills (TSSD) were specifically designed to promote rhythmic unloading and loading of the legs. The purpose of this study was to evaluate the effects of a TSSD training session on the swing rhythm and clubhead speed (CHS) among competitive junior golfers (3.1 ± 4.4 hcp). The driver swings (7 swings each) of 10 competitive junior golfers (aged 15-18) were captured before and after a TSSD session consisting of four stages (lasting less than 45 minutes). Post-TSSD training, there were significant increases in CHS (p < .001), maximum unweighting (p = .006), the trail-side push (p = .009), the horizontal motion ranges of the body and pelvis (p = .005-.031), the upward/downward motion range of the body in the backswing (p = .042/.024), and the backswing/downswing angular velocity peaks of the axle-chain system (p < .033). The stepping-like leg actions primarily facilitated horizontal motion rhythm over vertical motion and unweighting over push in terms of ground interaction. These findings suggest that TSSD can serve as an effective method for developing a rhythmic and dynamic motion pattern while increasing CHS.

4.
JMIR Public Health Surveill ; 10: e50466, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630526

RESUMO

BACKGROUND: Smoking ban policies (SBPs) are potent health interventions and offer the potential to influence antismoking behavior. The Korean government completely prohibited smoking in indoor sports facilities, including billiard halls, since the government revised the National Health Promotion Act in December 2017. OBJECTIVE: This study aimed to examine the impact of the SBP on the economic outcomes of indoor sports facilities, particularly billiard halls. METHODS: This study used credit card sales data from the largest card company in South Korea. Data are from January 2017 to December 2018. Monthly sales data were examined across 23 administrative neighborhoods in Seoul, the capital city of South Korea. We conducted the interrupted time series model using the fixed effects model and the linear regression with panel-corrected standard errors (PCSE). RESULTS: The sales and transactions of billiard halls were not significantly changed after the introduction of the SBP in the full PCSE models. The R2 of the full PCSE model was 0.967 for sales and 0.981 for transactions. CONCLUSIONS: The introduction of the SBP did not result in substantial economic gains or losses in the sales of billiard halls. In addition to existing price-based policies, the enhanced SBP in public-use facilities, such as billiard halls, can have a positive synergistic effect on reducing smoking prevalence and preventing secondhand smoke. Health policy makers can actively expand the application of SBPs and make an effort to enhance social awareness regarding the necessity and benefits of public SBPs for both smokers and the owners of hospitality facilities.


Assuntos
Política Antifumo , Política de Saúde , Mentol , Política Pública , República da Coreia/epidemiologia , Política Antifumo/economia
5.
Opt Express ; 32(6): 8736-8750, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38571124

RESUMO

A hyperspectral push-broom imager has been designed, constructed, and tested. The narrow angular selectivity of a weakly index modulated volume Bragg grating is utilized to replace the objective lens, slit, and collimating lens of a conventional slit-based hyperspectral push-broom imager. The imager comprises a dispersion grating, an angular filter grating, a focusing lens, and an image sensor. The imager has a field of view (FOV) of 17 degrees in the spatial direction, a spectral range from 400 nm to 900 nm, and a spectral resolution of 2.1 nm. The acquired hyperspectral data cubes are presented, and the influence of wavelength-dependent incident angle errors is analyzed.

6.
J Vet Sci ; 25(2): e22, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38568824

RESUMO

BACKGROUND: Achilles tendon is composed of dense connective tissue and is one of the largest tendons in the body. In veterinary medicine, acute ruptures are associated with impact injury or sharp trauma. Healing of the ruptured tendon is challenging because of poor blood and nerve supply as well as the residual cell population. Platelet-rich plasma (PRP) contains numerous bioactive agents and growth factors and has been utilized to promote healing in bone, soft tissue, and tendons. OBJECTIVE: The purpose of this study was to evaluate the healing effect of PRP injected into the surrounding fascia of the Achilles tendon after allograft in rabbits. METHODS: Donor rabbits (n = 8) were anesthetized and 16 lateral gastrocnemius tendons were fully transected bilaterally. Transected tendons were decellularized and stored at -80°C prior to allograft. The allograft was placed on the partially transected medial gastrocnemius tendon in the left hindlimb of 16 rabbits. The allograft PRP group (n = 8) had 0.3 mL of PRP administered in the tendon and the allograft control group (n = 8) did not receive any treatment. After 8 weeks, rabbits were euthanatized and allograft tendons were transected for macroscopic, biomechanical, and histological assessment. RESULTS: The allograft PRP group exhibited superior macroscopic assessment scores, greater tensile strength, and a histologically enhanced healing process compared to those in the allograft control group. CONCLUSIONS: Our results suggest administration of PRP on an allograft tendon has a positive effect on the healing process in a ruptured Achilles tendon.


Assuntos
Tendão do Calcâneo , Plasma Rico em Plaquetas , Traumatismos dos Tendões , Coelhos , Animais , Tendão do Calcâneo/cirurgia , Tendão do Calcâneo/lesões , Tendão do Calcâneo/patologia , Traumatismos dos Tendões/terapia , Traumatismos dos Tendões/veterinária , Traumatismos dos Tendões/patologia , Cicatrização , Aloenxertos/patologia
7.
Poult Sci ; 103(6): 103681, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38603932

RESUMO

Cellulitis is an important disease in commercial turkey farms associated with significant economic loss. Although the etiology of cellulitis is not fully elucidated, Clostridium septicum (C. septicum) is one of the main causes of this infectious disease. In this study, we report the development of a quantitative real-time PCR (qRT PCR) assay targeting the alpha-toxin gene (csa), which involves a prior 15-cyle PCR using a nested pair of primers to increase the detection sensitivity. Additionally, the TaqMan probe was employed to increase the target-specificity of the assay. The performance of our nested qRT-PCR assay was evaluated using Clostridium isolates from turkey farms, representing both septicum and non-septicum species, as well as sponge swab samples from turkey farms. Our step-by-step development of the assay showed that the csa gene is a suitable target for specific detection of C. septicum strains and that the inclusion of nested PCR step significantly increased the detection sensitivity of the final qRT PCR assay. The performance of the assay was also validated by a high correlation of the threshold cycle numbers of the qRT PCR assay with the relative abundance of C. septicum read counts in 16S rRNA gene microbiota profiles of the C. septicum-containing samples from turkey farms.

8.
Anal Biochem ; 691: 115533, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38642818

RESUMO

For irreversible denaturation transitions such as those exhibited by monoclonal antibodies, differential scanning calorimetry provides the denaturation temperature, Tm, the rate of denaturation at Tm, and the activation energy at Tm. These three quantities are essential but not sufficient for an accurate extrapolation of the rate of denaturation to temperatures of 25 °C and below. We have observed that the activation energy is not constant but temperature dependent due to the existence of an activation heat capacity, Cp,a. It is shown in this paper that a model that incorporates Cp,a is able to account for previous observations like, for example, that increasing the Tm does not always improve the stability at low temperatures; that some antibodies exhibit lower stabilities at 5 °C than at 25 °C; or that low temperature stabilities do not follow the rank order derived from Tm values. Most importantly, the activation heat capacity model is able to reproduce time dependent stabilities measured by size exclusion chromatography at low temperatures.

9.
Artigo em Inglês | MEDLINE | ID: mdl-38657581

RESUMO

INTRODUCTION: End-stage renal disease (ESRD) is a growing disease in Korea and worldwide and is an important condition that affects patient outcomes. In order to provide optimal management for mineral disturbance, vascular calcification, and bone disease of ESRD patients, the ORCHESTRA study (Korean dialysis cohort for mineral, vascular calcification, and fracture) was conducted and enrolled Korean dialysis patients. METHODS: Sixteen university-affiliated hospitals and one Veterans Health Service Medical Center participated in this study. This prospective cohort study enrolled approximately 900 consecutive dialysis patients between May 2019 and January 2021. Enrolled subjects were evaluated at baseline for demographic information, laboratory tests, radiologic imaging, and bone mineral densitometry (BMD) scans. After enrollment, regular assessments of patients were performed and their biospecimens were collected according to the study protocol. Primary outcomes were occurrence of major adverse cardiovascular events (MACE), invasive treatment for peripheral artery disease (PAD), and osteoporotic fractures. Secondary outcomes were hospitalization for cerebro-cardiovascular disease or progression of abdominal aortic calcification (AAC). Participants will be assessed for up to three years to determine whether primary or secondary outcomes occur. RESULTS: From May 2019 to January 2021, all participating centers recruited 900 consecutive dialysis patients, including 786 undergoing hemodialysis (HD) and 114 undergoing peritoneal dialysis (PD). The mean age of subjects was 60.4 ± 12.3 years. Males accounted for 57.7%. The mean dialysis vintage was 6.1 ± 6.0 years. The HD group was significantly older, had a longer dialysis vintage, and more comorbidities. Overall, the severity of vascular calcification was higher and the level of BMD was lower in the HD group than in the PD group. CONCLUSION: This is a nationwide, multicenter, prospective cohort study that focuses on CKD-mineral and bone disorder (CKD-MBD) and aims to provide clinical evidence to establish optimal treatment guidelines for Asian dialysis patients.

10.
JCI Insight ; 9(7)2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38587079

RESUMO

BACKGROUNDBroadly neutralizing monoclonal antibodies (bNAbs) represent a promising strategy for HIV-1 immunoprophylaxis and treatment. 10E8VLS and VRC07-523LS are bNAbs that target the highly conserved membrane-proximal external region (MPER) and the CD4-binding site of the HIV-1 viral envelope glycoprotein, respectively.METHODSIn this phase 1, open-label trial, we evaluated the safety and pharmacokinetics of 5 mg/kg 10E8VLS administered alone, or concurrently with 5 mg/kg VRC07-523LS, via s.c. injection to healthy non-HIV-infected individuals.RESULTSEight participants received either 10E8VLS alone (n = 6) or 10E8VLS and VRC07-523LS in combination (n = 2). Five (n = 5 of 8, 62.5%) participants who received 10E8VLS experienced moderate local reactogenicity, and 1 participant (n = 1/8, 12.5%) experienced severe local reactogenicity. Further trial enrollment was stopped, and no participant received repeat dosing. All local reactogenicity resolved without sequelae. 10E8VLS retained its neutralizing capacity, and no functional anti-drug antibodies were detected; however, a serum t1/2 of 8.1 days was shorter than expected. Therefore, the trial was voluntarily stopped per sponsor decision (Vaccine Research Center, National Institute of Allergy and Infectious Diseases [NIAID], NIH). Mechanistic studies performed to investigate the underlying reason for the reactogenicity suggest that multiple mechanisms may have contributed, including antibody aggregation and upregulation of local inflammatory markers.CONCLUSION10E8VLS resulted in unexpected reactogenicity and a shorter t1/2 in comparison with previously tested bNAbs. These studies may facilitate identification of nonreactogenic second-generation MPER-targeting bNAbs, which could be an effective strategy for HIV-1 immunoprophylaxis and treatment.TRIAL REGISTRATIONClinicaltrials.gov, accession no. NCT03565315.FUNDINGDivision of Intramural Research, National Institute of Allergy and Infectious Diseases, NIH.


Assuntos
Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Infecções por HIV/tratamento farmacológico , Infecções por HIV/prevenção & controle , Anticorpos Anti-HIV , Anticorpos Amplamente Neutralizantes/farmacologia , Anticorpos Monoclonais/farmacologia
11.
STAR Protoc ; 5(2): 102946, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38470911

RESUMO

Drosophila intestinal tumors show an extended cellular heterogeneity. We devise a protocol to assess tumor cell heterogeneity by employing nuclear size measurement and immunofluorescence-based cell lineage analysis. We describe steps for intestinal dissection, staining, and imaging, followed by detailed procedures for nuclear size analysis. This approach detects overall heterogeneity across the entire tumor cell population and deviations within specific cell populations. The procedure is also applicable for analyzing the heterogeneity of wild-type intestinal cells in various contexts. For complete details on the use and execution of this protocol, please refer to Pranoto et al.1.

12.
J Neurochem ; 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38515326

RESUMO

As persistent elevation of transforming growth factor-ß (TGF-ß) promotes fibrosis of muscles and joints and accelerates disease progression in amyotrophic lateral sclerosis (ALS), we investigated whether inhibition of TGF-ß would be effective against both exacerbations. The effects of TGF-ß and its inhibitor on myoblasts and fibroblasts were tested in vitro and confirmed in vivo, and the dual action of a TGF-ß inhibitor in ameliorating the pathogenic role of TGF-ß in ALS mice was identified. In the peripheral neuromuscular system, fibrosis in the muscles and joint cavities induced by excessive TGF-ß causes joint contracture and muscular degeneration, which leads to motor dysfunction. In an ALS mouse model, an increase in TGF-ß in the central nervous system (CNS), consistent with astrocyte activity, was associated with M1 microglial activity and pro-inflammatory conditions, as well as with neuronal cell death. Treatment with the TGF-ß inhibitor halofuginone could prevent musculoskeletal fibrosis, resulting in the alleviation of joint contracture and delay of motor deterioration in ALS mice. Halofuginone could also reduce glial cell-induced neuroinflammation and neuronal apoptosis. These dual therapeutic effects on both the neuromuscular system and the CNS were observed from the beginning to the end stages of ALS; as a result, treatment with a TGF-ß inhibitor from the early stage of disease delayed the time of symptom exacerbation in ALS mice, which led to prolonged survival.

13.
Acute Crit Care ; 39(1): 127-137, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38476065

RESUMO

BACKGROUND: The Controlling Nutritional Status (CONUT) score and the prognostic nutritional index (PNI) have emerged as important nutritional indices because they provide an objective assessment based on data. We aimed to investigate how these nutritional indices relate to outcomes in patients with sepsis. METHODS: Data were collected retrospectively at five hospitals for patients aged ≥18 years receiving treatment for sepsis between January 1, 2017, and December 31, 2021. Serum albumin and total cholesterol concentrations, and peripheral lymphocytes were used to calculate the CONUT score and PNI. To identify predictors correlated with 30-day mortality, analyses were conducted using univariate and multivariate Cox proportional hazards models. RESULTS: The 30-day mortality rate among 9,763 patients was 15.8% (n=1,546). The median CONUT score was 5 (interquartile range [IQR], 3-7) and the median PNI score was 39.6 (IQR, 33.846.4). Higher 30-day mortality rates were associated with individuals with moderate (CONUT score: 5-8; PNI: 35-38) or severe (CONUT: 9-12; PNI: <35) malnutrition compared with those with no malnutrition (CONUT: 0-1; PNI: >38). With CONUT scores, the hazard ratio (HR) associated with moderate malnutrition was 1.52 (95% confidence interval [CI], 1.24-1.87; P<0.001); for severe, HR=2.42 (95% CI, 1.95-3.02; P<0.001). With PNI scores, the HR for moderate malnutrition was 1.29 (95% CI, 1.09-1.53; P=0.003); for severe, HR=1.88 (95% CI, 1.67-2.12; P<0.001). CONCLUSIONS: The nutritional indices CONUT score and PNI showed significant associations with mortality of sepsis patients within 30 days.

14.
J Nutr ; 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38484978

RESUMO

BACKGROUND: Substantial evidence has demonstrated that maternal high-fat (HF) consumption during gestation and lactation plays as a risk factor for neurodevelopmental alterations and subsequent neurological disorders. OBJECTIVE: We investigated the regulatory mechanisms of maternal fat consumption on brain development and function in offspring at different ages. METHODS: Mouse dams were fed either a control diet [low-fat (LF)] or an HF diet for 3 wk before mating and throughout pregnancy and lactation. Offspring were killed at postnatal day (PD) 21 (LF21 and HF21), and the rest were fed an HF diet for 12 wk until the killing at PD 105 (LF105 and HF105). The expression levels of genes and proteins in the brains of offspring were analyzed by microarray and immunoblotting, respectively. RESULTS: Maternal dietary fat content, offspring age, and their interaction affected the expression levels of 1215, 10,453, and 2105 genes, respectively. The 67 differentially expressed genes (DEGs) between the HF21 and LF21 groups were enriched in several Gene Ontology terms related to nervous system development. Among 45 DEGs of the HF105/LF105 comparison, several genes associated with neurotransmitter action are detected. In addition, we observed increased activation of the AMP-dependent protein kinase-cAMP response element binding protein signaling pathway in HF105/LF105 comparison. However, maternal fat content did not change the protein levels of amyloid-ß and tau hyperphosphorylation, the markers of neuropathogenesis. CONCLUSIONS: Maternal HF feeding altered the expression of genes involved in the development and neurotransmitter system in the brains of PD 21 and HF diet-fed PD 105 offspring, respectively. Especially, the absence of overlap between DEGs at each comparison highlights the dynamic nature of alterations in gene expression in offspring of dams fed an HF diet. Further investigation on older adult offspring is necessary to elucidate the effects of maternal fat intake on the brain pathophysiology of offspring.

16.
Bull Hosp Jt Dis (2013) ; 82(1): 110-47, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38431971

RESUMO

The evolution of total elbow arthroplasty (TEA) has laid the groundwork for modern day TEA and has contributed to our understanding of elbow biomechanics. Trends in the usage of TEA have also varied significantly over time. This article aims to review the history and evolution of the TEA implant with a focus on modern day implant biomechanics and the trends in TEA indications. Additionally, this review discusses various complications that can occur with modern day TEA and looks toward the future to identify innovation and future trends.


Assuntos
Articulação do Cotovelo , Cotovelo , Humanos , Articulação do Cotovelo/cirurgia , Fenômenos Biomecânicos , Artroplastia
17.
Med Biol Eng Comput ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38451418

RESUMO

Revision total knee arthroplasty (TKA) is associated with a higher risk of readmission than primary TKA. Identifying individual patients predisposed to readmission can facilitate proactive optimization and increase care efficiency. This study developed machine learning (ML) models to predict unplanned readmission following revision TKA using a national-scale patient dataset. A total of 17,443 revision TKA cases (2013-2020) were acquired from the ACS NSQIP database. Four ML models (artificial neural networks, random forest, histogram-based gradient boosting, and k-nearest neighbor) were developed on relevant patient variables to predict readmission following revision TKA. The length of stay, operation time, body mass index (BMI), and laboratory test results were the strongest predictors of readmission. Histogram-based gradient boosting was the best performer in distinguishing readmission (AUC: 0.95) and estimating the readmission probability for individual patients (calibration slope: 1.13; calibration intercept: -0.00; Brier score: 0.064). All models produced higher net benefit than the default strategies of treating all or no patients, supporting the clinical utility of the models. ML demonstrated excellent performance for the prediction of readmission following revision TKA. Optimization of important predictors highlighted by our model may decrease preventable hospital readmission following surgery, thereby leading to reduced financial burden and improved patient satisfaction.

18.
Heliyon ; 10(5): e26930, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38463804

RESUMO

A series of experimental studies were conducted for cylindrical structures subjected to underwater shock loading to understand their dynamic responses and failure characteristics. All tests were performed inside an anechoic water tank. The submerged test cylinders were freely suspended, and an underwater shock loading was generated by the Compressed Air Shock Pipe Underwater Release (CASPUR) system. Cylinders were made of two different materials. The first group of cylinders was fabricated from carbon fiber and resin using the filament winding technique. The winding angles were ± 45° resulting in the same properties along axial and hoop directions. The second group of cylinders was constructed using a 3-D printer with polylactic acid (PLA) material. The 3-D printed cylinders had an orthotropic material property with different values in the axial and hoop directions. Both single-wall and double-wall cylindrical structures were tested. The latter consisted of two concentric cylinders of different diameters with uniform spacing between them. In addition, within the single-wall cylinders and the annuli of double-wall cylinders, the water fill was varied at 0%, 50%, or 100%. Pressure and strain gages were used to measure the shock pressure and deformation of the cylinders. The number of cylinders such as single-wall or double-wall and the internal water resulted in significant effects on the measured dynamic response (i.e., strain gage response) as well as the failure loading and failure characteristics including major failure locations. Internal water reduced the strain on the cylinders and made them withstand greater shock loading for both single-wall and double-wall cylinders.

19.
Artigo em Inglês | MEDLINE | ID: mdl-38418215

RESUMO

BACKGROUND: Optic neuritis (ON) prognosis is influenced by various factors including attack severity, underlying aetiologies, treatments and consequences of previous episodes. This study, conducted on a large cohort of first ON episodes, aimed to identify unique prognostic factors for each ON subtype, while excluding any potential influence from pre-existing sequelae. METHODS: Patients experiencing their first ON episodes, with complete aquaporin-4 (AQP4) and myelin oligodendrocyte glycoprotein (MOG) antibody testing, and clinical data for applying multiple sclerosis (MS) diagnostic criteria, were enrolled. 427 eyes from 355 patients from 10 hospitals were categorised into four subgroups: neuromyelitis optica with AQP4 IgG (NMOSD-ON), MOG antibody-associated disease (MOGAD-ON), ON in MS (MS-ON) or idiopathic ON (ION). Prognostic factors linked to complete recovery (regaining 20/20 visual acuity (VA)) or moderate recovery (regaining 20/40 VA) were assessed through multivariable Cox regression analysis. RESULTS: VA at nadir emerged as a robust prognostic factor for both complete and moderate recovery, spanning all ON subtypes. Early intravenous methylprednisolone (IVMP) was associated with enhanced complete recovery in NMOSD-ON and MOGAD-ON, but not in MS-ON or ION. Interestingly, in NMOSD-ON, even a slight IVMP delay in IVMP by >3 days had a significant negative impact, whereas a moderate delay up to 7-9 days was permissible in MOGAD-ON. Female sex predicted poor recovery in MOGAD-ON, while older age hindered moderate recovery in NMOSD-ON and ION. CONCLUSION: This comprehensive multicentre analysis on first-onset ON unveils subtype-specific prognostic factors. These insights will assist tailored treatment strategies and patient counselling for ON.

20.
Dent Mater ; 40(4): 653-663, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38378372

RESUMO

OBJECTIVE: This study aimed to compare the four-point flexural strength of CAM-milled and sintered (as-sintered, AS) specimens with those of high-polished (HP) specimens using chairside polishing systems to simulate clinical surface conditions. METHODS: Seven full-contour zirconia CAM/CAM blanks with various yttria contents (3, 4, 5 mol%) including three high-translucent groups (5Y) were selected to prepare flexural specimens. The bend bar specimens (2.0 × 4.0 × 25.0 mm3) were fabricated by using STL file and dental CAM machine with the respective zirconia blanks (98 mm ϕ and 10-14 mm in height). Twelve bar specimens were machined from one zirconia puck and a total of 24 specimens were prepared from each group. The pre-sintered bar specimens were sintered by using a dental zirconia furnace at 1530-1550 °C for 2 h according to the instructions. All sintered specimens were divided into two groups: as-sintered (AS) group and high-polished (HP) groups (n = 12). HP groups were subjected to polishing one surface of specimens using a three-step polishing system and finally finished with diamond polishing. After cleaning and drying, the flexural strength of all specimens was determined by a fully articulating four-point flexure fixture consisting of a 1/4-point test configuration with an inner/outer span of 10/20 mm. Statistical differences between AS and HP groups were conducted with Weibull analysis. The fractured surfaces of zirconia specimens were observed using a field emission SEM and EDS to detect failure origins. RESULTS: The mean AS flexural strength values were significantly lower than those of HP counterparts. However, Weibull moduli expressing the reliability of HP groups were generally decreased although not significantly in comparison to their AS. The fracture of the AS specimens mostly originated from extrinsic CAM-milling defects, while the HP specimens were fractured from intrinsic subsurface or volume defects including pores, large grain clusters, inclusions, and corner-located critical flaws. Two high-translucent (5Y) zirconia groups were not affected in their strength and reliability after polishing, whereas one 5Y zirconia significantly increased its strength but significantly lowered its reliability. SIGNIFICANCE: The extrinsic and intrinsic strength-limiting defects should be considered in evaluating the flexural strength and reliability of dental CAD/CAM zirconia ceramics for full-contour restorations. For the materials tested in this study, more optimized processing of blanks and milling protocols of pre-sintered zirconia blanks should be developed including post-sintering surface finishing to reduce the flaw population regulating strength and reliability which will affect the survivability of dental zirconia prostheses.


Assuntos
Cerâmica , Materiais Dentários , Teste de Materiais , Reprodutibilidade dos Testes , Zircônio , Propriedades de Superfície , Ítrio
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