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1.
Small ; : e2400374, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38566523

RESUMEN

Highly efficient water splitting electrocatalyst for producing hydrogen as a renewable energy source offers potential to achieve net-zero. However, it has significant challenges in using transition metal electrocatalysts as alternatives to noble metals due to their low efficiency and durability, furthermore, the reliance on electricity generation for electrocatalysts from fossil fuels leads to unavoidable carbon emissions. Here, a highly efficient self-powered water splitting system integrated is designed with triboelectric nanogenerator (TENG) and Ni3FeN@Fe24N10 catalyst with improved catalytic activity and durability. First, the durability of the Ni3FeN catalyst is improved by forming N, P carbon shell using melamine, polyetherimide, and phytic acid. The catalyst activity is improved by generating Fe24N10 in the carbon shell through the Kirkendall effect. The synthesized Ni3FeN@Fe24N10 catalyst exhibited excellent bifunctional catalytic activity (ηOER = 261.8 mV and ηHER = 151.8 mV) and remarkable stability (91.7% in OER and 90.5% in HER) in 1 m KOH. Furthermore, to achieve ecofriendly electricity generation, a rotation-mode TENG that sustainably generate high-performance is realized using butylated melamine formaldehyde. As a result, H2 is successfully generated using the integrated system composed of the designed TENG and catalyst. The finding provides a promising approach for energy generation to achieve net-zero.

2.
Crit Care ; 28(1): 138, 2024 04 25.
Artículo en Inglés | MEDLINE | ID: mdl-38664807

RESUMEN

BACKGROUND: This study aimed to validate apparent diffusion coefficient (ADC) values and thresholds to predict poor neurological outcomes in out-of-hospital cardiac arrest (OHCA) survivors by quantitatively analysing the ADC values via brain magnetic resonance imaging (MRI). METHODS: This observational study used prospectively collected data from two tertiary academic hospitals. The derivation cohort comprised 70% of the patients randomly selected from one hospital, whereas the internal validation cohort comprised the remaining 30%. The external validation cohort used the data from another hospital, and the MRI data were restricted to scans conducted at 3 T within 72-96 h after an OHCA experience. We analysed the percentage of brain volume below a specific ADC value at 50-step intervals ranging from 200 to 1200 × 10-6 mm2/s, identifying thresholds that differentiate between good and poor outcomes. Poor neurological outcomes were defined as cerebral performance categories 3-5, 6 months after experiencing an OHCA. RESULTS: A total of 448 brain MRI scans were evaluated, including a derivation cohort (n = 224) and internal/external validation cohorts (n = 96/128, respectively). The proportion of brain volume with ADC values below 450, 500, 550, 600, and 650 × 10-6 mm2/s demonstrated good to excellent performance in predicting poor neurological outcomes in the derivation group (area under the curve [AUC] 0.89-0.91), and there were no statistically significant differences in performances among the derivation, internal validation, and external validation groups (all P > 0.5). Among these, the proportion of brain volume with an ADC below 600 × 10-6 mm2/s predicted a poor outcome with a 0% false-positive rate (FPR) and 76% (95% confidence interval [CI] 68-83) sensitivity at a threshold of > 13.2% in the derivation cohort. In both the internal and external validation cohorts, when using the same threshold, a specificity of 100% corresponded to sensitivities of 71% (95% CI 58-81) and 78% (95% CI 66-87), respectively. CONCLUSIONS: In this validation study, by consistently restricting the MRI types and timing during quantitative analysis of ADC values in brain MRI, we observed high reproducibility and sensitivity at a 0% FPR. Prospective multicentre studies are necessary to validate these findings.


Asunto(s)
Paro Cardíaco Extrahospitalario , Humanos , Femenino , Masculino , Persona de Mediana Edad , Anciano , Paro Cardíaco Extrahospitalario/diagnóstico por imagen , Estudios Prospectivos , Pronóstico , Sobrevivientes/estadística & datos numéricos , Estudios de Cohortes , Imagen por Resonancia Magnética/métodos , Imagen de Difusión por Resonancia Magnética/métodos , Valor Predictivo de las Pruebas , Encéfalo/diagnóstico por imagen , Encéfalo/fisiopatología
3.
Am J Emerg Med ; 78: 22-28, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38181542

RESUMEN

BACKGROUND: To determine if the density distribution proportion of Hounsfield unit (HUdp) in head computed tomography (HCT) images can be used to quantitatively measure cerebral edema in survivors of out-of-hospital cardiac arrest (OHCA). METHODS: This retrospective observational study included adult comatose OHCA survivors who underwent HCT within 6 h (first) and 72-96 h (second), all performed using the same CT scanner. Semi-automated quantitative analysis was used to identify differences in HUdp at specific HU ranges across the intracranial component based on neurological outcome. Cerebral edema was defined as the increased displacement of the sum of HUdp values (ΔHUdp) at a specific range between two HCT scans. Poor neurological outcome was defined as cerebral performance categories 3-5 at 6 months after OHCA. RESULTS: Twenty-three (42%) out of 55 patients had poor neurological outcome. Significant HUdp differences were observed between good and poor neurological outcomes in the second HCT scan at HU = 1-14, 23-35, and 39-56 (all P < 0.05). Only the ΔHUdp = 23-35 range showed a significant increase and correlation in the poor neurological outcome group (4.90 vs. -0.72, P < 0.001) with the sum of decreases in the other two ranges (r = 0.97, P < 0.001). Multivariate logistic regression analysis demonstrated a significant association between ΔHUdp = 23-35 range and poor neurological outcomes (adjusted OR, 1.12; 95% CI: 1.02-1.24; P = 0.02). CONCLUSION: In this cohort study, the increased displacement in ΔHUdp = 23-35 range is independently associated with poor neurological outcome and provides a quantitative assessment of cerebral edema formation in OHCA survivors.


Asunto(s)
Edema Encefálico , Paro Cardíaco Extrahospitalario , Adulto , Humanos , Edema Encefálico/etiología , Edema Encefálico/complicaciones , Estudios de Cohortes , Pronóstico , Paro Cardíaco Extrahospitalario/diagnóstico por imagen , Paro Cardíaco Extrahospitalario/terapia , Paro Cardíaco Extrahospitalario/complicaciones , Tomografía Computarizada por Rayos X/métodos , Estudios Retrospectivos , Sobrevivientes
4.
Medicina (Kaunas) ; 60(2)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38399609

RESUMEN

Background and Objectives: The purpose of this study was to compare clinical outcomes and polyethylene (PE) insert thickness between total knee arthroplasty (TKA) systems providing 1 mm and 2 mm increments. Materials and Methods: In this randomized controlled trial, 50 patients (100 knees) undergoing same-day or staggered bilateral TKA were randomized to receive a TKA system providing 1 mm increments in one knee (1 mm group) and a TKA system providing 2 mm increments in the other knee (2 mm group). At 2 years postoperatively, Knee Society Score (KSS), Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score, Forgotten Joint Score (FJS), range of motion (ROM), and insert thicknesses were compared between the groups. Results: A total of 47 patients (94 knees) participated in follow-up analysis. In each group, patient-reported outcomes improved significantly after TKA (all, p < 0.05). There were no significant differences in patient-reported outcomes. The mean ROM was not significantly different between groups at preoperative and 2-year points. The rate of postoperative flexion contracture ≥ 5° was 2.1% and 4.3%, and the rate of postoperative recurvatum ≥ 5° was 4.3% and 2.1% in the 1 mm group and 2 mm, respectively (all, p = 1.000). Mean insert thickness was significantly thinner in the 1 mm group than the 2 mm group (p = 0.001). The usage rate of a thick insert (≥14 mm) was 12.7% and 38.3% in the 1 mm group and 2 mm group (p = 0.005). Conclusions: The use of a TKA system providing 1 mm PE insert thickness increments offered no clinical benefit in terms of patient reported outcomes over systems with 2 mm increments at 2 years of follow-up. However, the TKA system with 1 mm increments showed significantly thinner PE insert usage. As a theoretical advantage of 1 mm increments has yet to be proven, the mid- to long-term effects of thinner PE insert usage must be determined.


Asunto(s)
Prótesis de la Rodilla , Osteoartritis de la Rodilla , Humanos , Polietileno/uso terapéutico , Resultado del Tratamiento , Articulación de la Rodilla/cirugía , Rodilla , Osteoartritis de la Rodilla/cirugía , Rango del Movimiento Articular
5.
Crit Care ; 27(1): 16, 2023 01 13.
Artículo en Inglés | MEDLINE | ID: mdl-36639809

RESUMEN

BACKGROUND: This study aimed to investigate the association between ultra-early (within 6 h after return of spontaneous circulation [ROSC]) brain diffusion-weighted magnetic resonance imaging (DW-MRI) and neurological outcomes in comatose survivors after out-of-hospital cardiac arrest. METHODS: We conducted a registry-based observational study from May 2018 to February 2022 at a Chungnam national university hospital in Daejeon, Korea. Presence of high-signal intensity (HSI) (PHSI) was defined as a HSI on DW-MRI with corresponding hypoattenuation on the apparent diffusion coefficient map irrespective of volume after hypoxic ischemic brain injury; absence of HSI was defined as AHSI. The primary outcome was the dichotomized cerebral performance category (CPC) at 6 months, defined as good (CPC 1-2) or poor (CPC 3-5). RESULTS: Of the 110 patients (30 women [27.3%]; median (interquartile range [IQR]) age, 58 [38-69] years), 48 (43.6%) had a good neurological outcome, time from ROSC to MRI scan was 2.8 h (IQR 2.0-4.0 h), and the PHSI on DW-MRI was observed in 46 (41.8%) patients. No patients in the PHSI group had a good neurological outcome compared with 48 (75%) patients in the AHSI group. In the AHSI group, cerebrospinal fluid (CSF) neuron-specific enolase (NSE) levels were significantly lower in the group with good neurological outcome compared to the group with poor neurological outcome (20.1 [14.4-30.7] ng/mL vs. 84.3 [32.4-167.0] ng/mL, P < 0.001). The area under the curve for PHSI on DW-MRI was 0.87 (95% confidence interval [CI] 0.80-0.93), and the specificity and sensitivity for predicting a poor neurological outcome were 100% (95% CI 91.2%-100%) and 74.2% (95% CI 62.0-83.5%), respectively. A higher sensitivity was observed when CSF NSE levels were combined (88.7% [95% CI 77.1-95.1%]; 100% specificity). CONCLUSIONS: In this cohort study, PHSI findings on ultra-early DW-MRI were associated with poor neurological outcomes 6 months following the cardiac arrest. The combined CSF NSE levels showed higher sensitivity at 100% specificity than on DW-MRI alone. Prospective multicenter studies are required to confirm these results.


Asunto(s)
Paro Cardíaco Extrahospitalario , Femenino , Humanos , Persona de Mediana Edad , Encéfalo , Estudios de Cohortes , Imagen de Difusión por Resonancia Magnética/métodos , Paro Cardíaco Extrahospitalario/complicaciones , Paro Cardíaco Extrahospitalario/diagnóstico por imagen , Fosfopiruvato Hidratasa , Pronóstico , Estudios Prospectivos , Masculino , Adulto , Anciano
6.
Crit Care ; 27(1): 407, 2023 10 25.
Artículo en Inglés | MEDLINE | ID: mdl-37880777

RESUMEN

BACKGROUND: This study aimed to quantitatively analyse ultra-early brain diffusion-weighted magnetic resonance imaging (DW-MRI) findings to determine the apparent diffusion coefficient (ADC) threshold associated with neurological outcomes in comatose survivors of out-of-hospital cardiac arrest (OHCA). METHODS: This retrospective study included adult survivors of comatose OHCA who underwent DW-MRI imaging scans using a 3-T MRI scanner within 6 h of the return of spontaneous circulation (ROSC). We investigated the association between neurological outcomes and ADC values obtained through voxel-based analysis on DW-MRI. Additionally, we constructed multivariable logistic regression models with pupillary light reflex (PLR), serum neuron-specific enolase (NSE), and ADC values as independent variables to predict poor neurological outcomes. The primary outcome was poor neurological outcome 6 months after ROSC, determined by the Cerebral Performance Category 3-5. RESULTS: Overall, 131 patients (26% female) were analysed, of whom 74 (57%) showed poor neurological outcomes. The group with a poor neurological outcome had lower mean whole brain ADC values (739.1 vs. 787.1 × 10-6 mm/s) and higher percentages of voxels with ADC below threshold in all ranges (250-1150) (all P < 0.001). The mean whole brain ADC values (area under the receiver operating characteristic curve [AUC] 0.83) and the percentage of voxels with ADC below 600 (AUC 0.81) had the highest sensitivity of 51% (95% confidence interval [CI] 39.4-63.1; cut-off value ≤ 739.2 × 10-6 mm2/s and > 17.2%, respectively) when the false positive rate (FPR) was 0%. In the multivariable model, which also included PLR, NSE, and mean whole brain ADC values, poor neurological outcome was predicted with the highest accuracy (AUC 0.91; 51% sensitivity). This model showed more accurate prediction and sensitivity at an FPR of 0% than did the combination of PLR and NSE (AUC 0.86; 30% sensitivity; P = 0.03). CONCLUSIONS: In this cohort study, early voxel-based quantitative ADC analysis after ROSC was associated with poor neurological outcomes 6 months after cardiac arrest. The mean whole brain ADC value demonstrated the highest sensitivity when the FPR was 0%, and including it in the multivariable model improved the prediction of poor neurological outcomes.


Asunto(s)
Paro Cardíaco Extrahospitalario , Adulto , Humanos , Femenino , Masculino , Paro Cardíaco Extrahospitalario/complicaciones , Paro Cardíaco Extrahospitalario/diagnóstico por imagen , Imagen de Difusión por Resonancia Magnética/métodos , Coma , Estudios de Cohortes , Estudios Retrospectivos , Pronóstico , Sobrevivientes
7.
Microsc Microanal ; 29(5): 1618-1627, 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37584512

RESUMEN

The growing demands of nanoscience require the continuous improvement of visualization methods. The imaging performance of scanning electron microscopy (SEM) is fundamentally limited by the point spread function of the electron beam and degrades because of noise. This paper proposes an auto-optimization algorithm based on deconvolution for the restoration of SEM images. This algorithm uses a constrained least squares filter and does not dependent on the user's experience or the availability of nondegraded images. The proposed algorithm improved the quality of the SEM images of 10-nm Au nanoparticles, and achieved balance among the sharpness, contrast-to-noise ratio (CNR), and image artifacts. For the SEM image of 100-nm pitched line patterns, the analysis of the spatial frequencies allowed the 2.5-fold improvement of the intensity of 4-nm information, and the noise floor decreased approximately 32 times. Along with the results obtained by the application of the proposed algorithm to images of tungsten disulfide (WS2) flakes, carbon nanotubes (CNTs), and HeLa cells, the evaluation results confirm that the proposed algorithm can enhance the SEM imaging of nanoscale features that lie close to the microscope's resolution limit.

8.
Microsc Microanal ; 29(6): 2004-2013, 2023 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-37855685

RESUMEN

To date, lanthanum hexaboride (LaB6) thermionic electron sources have not been able fully to capitalize on their inherent potential, resulting in an ambiguous position within the application area. Although they exhibit higher brightness compared with a tungsten filament source, they still fall short of the performance of Schottky electron sources. This study aims to explore the capabilities of the LaB6 electron source under different operating conditions to bridge the gap, ultimately to realize its untapped potential. Simulations in virtual source mode indicated enhanced beam brightness and a reduced beam half-angle with an increase the extraction voltage, promising up to tenfold times higher beam brightness compared with the crossover mode. The energy distribution measured using a prelens retarding field energy analyzer revealed an energy distribution of 0.55 eV and a high angular current density of 33 mA/sr in the virtual source mode. Therefore, the virtual source mode of LaB6 can provide a narrow energy distribution akin to that of a ZrO/W Schottky electron gun (1600 K) while having an angular current density over 2,000 times higher. In addition, the stability of the virtual source mode is ±0.022%, while that of the crossover mode is ±0.138%.

9.
J Arthroplasty ; 38(1): 78-84, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35934188

RESUMEN

BACKGROUND: Given higher component conformity, rotational availability of polyethylene insert, and more physiologic patellofemoral tracking, mobile-bearing (MB) total knee arthroplasty (TKA) is supposed to offer advantages in joint perception and crepitus. The purpose of this study was to investigate whether MB TKA offers superior outcomes over fixed-bearing (FB) TKA in terms of joint awareness and crepitus. METHODS: This prospective, randomized, controlled trial included 49 FB and 49 MB TKAs that shared the same posterior-stabilized femoral component. Primary outcomes included joint awareness assessed with the Forgotten Joint Score and crepitus graded according to severity and sound at 3 years postoperatively. Secondary outcomes were the range of motion, the Knee Society Score, Western Ontario and McMaster Universities Osteoarthritis Index, component position, and joint line level on radiographs. RESULTS: The Forgotten Joint Score showed no significant difference between the FB (67 points; range, 0-100) and MB groups (63 points; range, 13-100) (P = .440). For crepitus, no significant differences were found in the overall incidence rate (FB group, 18%; MB group, 12%; P = .386) and grade (grade 1, 6 versus 5; grade 2, 2 versus 1; grade 3, 1 versus 0, respectively). There were no significant differences in range of motion, Knee Society Score, and Western Ontario and McMaster Universities Osteoarthritis Index, as well as radiographic outcomes between the two groups (all, P > .05). CONCLUSION: MB TKA offers no benefits in terms of joint awareness and crepitus compared with FB TKA at mean 3 years postoperatively. The theoretical advantages of MB TKA have yet to be demonstrated in practice, leaving the selection of bearing type to the surgeon's judgment. LEVEL OF EVIDENCE: Level II.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Prótesis de la Rodilla , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/cirugía , Estudios Prospectivos , Diseño de Prótesis , Articulación de la Rodilla/cirugía , Rango del Movimiento Articular
10.
J Arthroplasty ; 38(4): 662-667, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36309143

RESUMEN

BACKGROUND: The purpose of this study was to investigate whether generalized joint laxity affects the postoperative alignment and clinical outcomes of medial opening-wedge high tibial osteotomy (MOWHTO). METHODS: A total of 198 patients who underwent MOWHTO was divided into two groups according to absence or presence of generalized joint laxity. Generalized joint laxity was measured using the Beighton and Horan criteria, and a score of 4 or more out of 9 was defined as generalized joint laxity. A weight bearing line (WBL) ratio of 55% to 70% was considered an acceptable postoperative lower limb alignment range; WBL over 70% was defined as overcorrection and less than 55% as undercorrection. The WBL ratio was investigated before and 2 years after surgery, and the Western Ontario McMaster University Osteoarthritis Index scale score (WOMAC) was evaluated for patient-reported outcomes (PRO) of MOWHTO. There were 147 (73.7%) patients in the nongeneralized joint laxity group and 51 (26.3%) in the generalized joint laxity group. Preoperatively, there was no difference between the two groups in hip-knee-ankle (HKA) angle or WBL ratio (all P > .05). RESULTS: At 2 years postoperatively, the generalized joint laxity group showed significantly higher HKA angle and WBL ratio than the nongeneralized joint laxity group (all P < .05). There was a significant difference in the distribution ratio of undercorrection, normocorrection, and overcorrection patients between the two groups (P < .05). There were no differences between the two groups in preoperative and postoperative WOMAC scores (all, P > .05). CONCLUSION: The generalized joint laxity significantly affected postoperative over correction of alignment following MOWHTO. However, there was no significant difference in PRO between the patients who did and did not have generalized joint laxity after MOWHTO until 2 years.


Asunto(s)
Inestabilidad de la Articulación , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/cirugía , Tibia/cirugía , Estudios Retrospectivos , Articulación de la Rodilla/cirugía , Osteotomía
11.
Int J Mol Sci ; 24(10)2023 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-37239986

RESUMEN

Let-7 miRNAs have pleiotropic cellular functions in cell proliferation, migration, and regenerative processes. Here, we investigate whether the inhibition of let-7 miRNAs with antisense oligonucleotides (ASOs) can be a transient and safe strategy enhancing the therapeutic potential of mesenchymal stromal cells (MSCs) to overcome their limitations in cell therapeutic trials. We first identified major subfamilies of let-7 miRNAs preferentially expressed in MSCs, and efficient ASO combinations against these selected subfamilies that mimic the effects of LIN28 activation. When let-7 miRNAs were inhibited with an ASO combination (anti-let7-ASOs), MSCs exhibited higher proliferation with delayed senescence during the passaging into a culture. They also exhibited increased migration and enhanced osteogenic differentiation potential. However, these changes in MSCs were not accompanied by cell-fate changes into pericytes or the additional acquisition of stemness, but instead occurred as functional changes accompanied by changes in proteomics. Interestingly, MSCs with let-7 inhibition exhibited metabolic reprogramming characterized by an enhanced glycolytic pathway, decreased reactive oxygen species, and lower transmembrane potential in mitochondria. Moreover, let-7-inhibited MSCs promoted the self-renewal of neighboring hematopoietic progenitor cells, and enhanced capillary formation in endothelial cells. These findings together show that our optimized ASO combination efficiently reprograms the MSC functional state, allowing for more efficient MSC cell therapy.


Asunto(s)
Células Madre Mesenquimatosas , MicroARNs , Osteogénesis , Oligonucleótidos Antisentido/genética , Oligonucleótidos Antisentido/farmacología , Oligonucleótidos Antisentido/metabolismo , Células Endoteliales/metabolismo , Células Madre Mesenquimatosas/metabolismo , Diferenciación Celular/genética , MicroARNs/metabolismo
12.
Medicina (Kaunas) ; 59(2)2023 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-36837570

RESUMEN

Background and Objectives Perioperative distal femoral fracture is rare in patients undergoing total knee arthroplasty (TKA). In such rare cases, additional fixation might be required, and recovery can be delayed. Several studies have focused on perioperative distal femoral fractures in TKA, but there remains a lack of information on risk factors. The purpose of this study was to investigate risk factors for perioperative distal femoral fractures in patients undergoing TKA and suggest preventive strategies. Materials and Methods: This retrospective study included a total of 5364 TKA cases in a single institution from 2011 to 2022. Twenty-four distal femoral fractures occurred during TKA or within one month postoperatively (0.45%). Patient demographics, intraoperative findings, and postoperative progress were obtained from patient medical records and radiographs. Risk factors for fractures were analyzed using multivariate Firth logistic regression analysis. Results: Although all 24 distal femoral fractures occurred in female patients (24 of 4819 patients, 0.50%), the incidence rate of fracture between male and female patients was not significantly different (p = 0.165). The presence of osteoporosis and insertion of a polyethylene (PE) insert with knee dislocation were statistically significant risk factors (p = 0.009 and p = 0.046, respectively). However, multivariate logistic regression analysis showed that only osteoporosis with bone mineral density (BMD) < -2.8 (odds ratio (2.30), 95% CI (1.03-5.54), p = 0.043) was an independent risk factor for perioperative distal femoral fracture in TKA patients. Conclusions: Our results suggest that osteoporosis with BMD < -2.8 is a risk factor for distal femoral fractures in patients undergoing TKA. In these patients, careful bone cutting, adequate gap balancing, and especially the use of the sliding method for insertion of a PE insert are recommended as preventive strategies.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Fracturas Femorales Distales , Fracturas del Fémur , Osteoporosis , Fracturas Periprotésicas , Humanos , Masculino , Femenino , Artroplastia de Reemplazo de Rodilla/efectos adversos , Estudios Retrospectivos , Fracturas Periprotésicas/complicaciones , Fracturas Periprotésicas/cirugía , Factores de Riesgo , Osteoporosis/etiología
13.
Medicina (Kaunas) ; 59(3)2023 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-36984635

RESUMEN

Background and objectives: Cartilage regeneration using mesenchymal stem cells (MSCs) has been attempted to improve articular cartilage regeneration in varus knee osteoarthritis (OA) patients undergoing high tibial osteotomy (HTO). Bone marrow aspirate concentrate (BMAC) and human umbilical cord blood-derived MSCs (hUCB-MSCs) have been reported to be effective. However, whether BMAC is superior to hUCB-MSCs remains unclear. This systematic review and meta-analysis aimed to determine the clinical efficacy of cartilage repair procedures with BMAC or hUCB-MSCs in patients undergoing HTO. Materials and Methods: A systematic search was conducted using three global databases, PubMed, EMBASE, and the Cochrane Library, for studies in which the clinical outcomes after BMAC or hUCB-MSCs were used in patients undergoing HTO for varus knee OA. Data extraction, quality control, and meta-analysis were performed. To compare the clinical efficacy of BMAC and hUCB-MSCs, reported clinical outcome assessments and second-look arthroscopic findings were analyzed using standardized mean differences (SMDs) with 95% confidence intervals (CIs). Results: The present review included seven studies of 499 patients who received either BMAC (BMAC group, n = 169) or hUCB-MSCs (hUCB-MSC group, n = 330). Improved clinical outcomes were found in both BMAC and hUCB-MSC groups; however, a significant difference was not observed between procedures (International Knee Documentation Committee score; p = 0.91, Western Ontario and McMaster Universities OA Index; p = 0.05, Knee Society Score (KSS) Pain; p = 0.85, KSS Function; p = 0.37). On second-look arthroscopy, the hUCB-MSC group showed better International Cartilage Repair Society Cartilage Repair Assessment grade compared with the BMAC group (p < 0.001). Conclusions: Both BMAC and hUCB-MSCs with HTO improved clinical outcomes in varus knee OA patients, and there was no difference in clinical outcomes between them. However, hUCB-MSCs were more effective in articular cartilage regeneration than BMAC augmentation.


Asunto(s)
Cartílago Articular , Células Madre Mesenquimatosas , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/cirugía , Médula Ósea , Sangre Fetal , Cartílago Articular/cirugía , Resultado del Tratamiento , Osteotomía/métodos
14.
Medicina (Kaunas) ; 59(4)2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37109740

RESUMEN

Background: prosthetic loosening after hip and knee arthroplasty is one of the most common causes of joint arthroplasty failure and revision surgery. Diagnosis of prosthetic loosening is a difficult problem and, in many cases, loosening is not clearly diagnosed until accurately confirmed during surgery. The purpose of this study is to conduct a systematic review and meta-analysis to demonstrate the analysis and performance of machine learning in diagnosing prosthetic loosening after total hip arthroplasty (THA) and total knee arthroplasty (TKA). Materials and Methods: three comprehensive databases, including MEDLINE, EMBASE, and the Cochrane Library, were searched for studies that evaluated the detection accuracy of loosening around arthroplasty implants using machine learning. Data extraction, risk of bias assessment, and meta-analysis were performed. Results: five studies were included in the meta-analysis. All studies were retrospective studies. In total, data from 2013 patients with 3236 images were assessed; these data involved 2442 cases (75.5%) with THAs and 794 cases (24.5%) with TKAs. The most common and best-performing machine learning algorithm was DenseNet. In one study, a novel stacking approach using a random forest showed similar performance to DenseNet. The pooled sensitivity across studies was 0.92 (95% CI 0.84-0.97), the pooled specificity was 0.95 (95% CI 0.93-0.96), and the pooled diagnostic odds ratio was 194.09 (95% CI 61.60-611.57). The I2 statistics for sensitivity and specificity were 96% and 62%, respectively, showing that there was significant heterogeneity. The summary receiver operating characteristics curve indicated the sensitivity and specificity, as did the prediction regions, with an AUC of 0.9853. Conclusions: the performance of machine learning using plain radiography showed promising results with good accuracy, sensitivity, and specificity in the detection of loosening around THAs and TKAs. Machine learning can be incorporated into prosthetic loosening screening programs.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Estudios Retrospectivos , Falla de Prótesis , Artroplastia de Reemplazo de Cadera/efectos adversos , Aprendizaje Automático , Reoperación
15.
Biochem Biophys Res Commun ; 629: 128-134, 2022 11 12.
Artículo en Inglés | MEDLINE | ID: mdl-36116375

RESUMEN

Chronic Kidney Disease (CKD) is increasingly recognized as a global public health issue. Diabetic nephropathy (DN), also known as diabetic kidney disease, is a leading cause of CKD. Regenerative medicine strategy employing nephron progenitor cells (NPCs) is worthy of consideration as an alternative to shortage of donor organs for kidney transplantation. In previous study, we successfully generated induced NPCs (iNPCs) from human urine-derived cells that resembled human embryonic stem cell-derived NPCs. Here, we aimed to investigate the therapeutic potential of iNPCs in DN animal model. The results revealed the therapeutic effect of iNPCs as follows: (1) diminished glomerular hypertrophy, (2) reduced tubulointerstitial fibrosis, (3) low blood urea nitrogen, serum creatinine and albuminuria value, (4) decreased inflammation/fibrosis, (5) enhanced renal regeneration and (6) confirmed safety. This study demonstrates that human iNPCs have a therapeutic potential as a cell source for transplantation in patients with kidney diseases.


Asunto(s)
Diabetes Mellitus , Nefropatías Diabéticas , Insuficiencia Renal Crónica , Animales , Creatinina , Diabetes Mellitus/patología , Nefropatías Diabéticas/tratamiento farmacológico , Fibrosis , Humanos , Riñón/patología , Ratones , Nefronas , Insuficiencia Renal Crónica/patología , Células Madre
16.
Microsc Microanal ; : 1-13, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35164889

RESUMEN

Low-voltage scanning electron microscopes (LV-SEMs) are widely used in nanoscience. However, image resolution for SEMs is restricted by chromatic aberration due to energy spread of the electron beam at low acceleration voltage. This study introduces a new monochromator (MC) with offset cylindrical lenses (CLs) as one solution for LV-SEMs. The MC optics, with highly excited CLs in offset layouts, has advantageous high performance and simple experimental setup, making it suitable for field emission LV-SEMs. In a preliminary evaluation, our MC reduced the energy spread from 770 to 67 meV. The MC was integrated into a commercial SEM equipped with an out-lens (a conventional objective lens without immersion magnetic or retarding electric fields) and an Everhart­Thornley detector. Comparing SEM images under two conditions with the MC turned on or off, the spatial resolution was improved by 58% at 0.5 and 1 keV. The filtering effect of the MC decreased the probe current with a ratio (i.e., transmittance) of 5.7%, which was consistent with estimations based on measured energy spreads. To the best of our knowledge, this is the first report on an effective MC with higher-energy resolution than 100 meV and the results offer encouraging prospects for LV-SEM technology.

17.
Microsc Microanal ; : 1-9, 2022 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-36062359

RESUMEN

The energy distribution of an electron gun is one of the most important characteristics determining the performance of electron beam-based instruments, such as electron microscopes and electron energy loss spectroscopes. For accurate measurements of the energy distribution, this study presents a novel retarding field energy analyzer (RFEA) with the feature of an additional integrated pre-lens, which enables an adjustment of beam trajectory into the analyzer. The advantages of this analyzer are its compact size and simple electrode configuration. According to trajectory simulation theories, the optimum condition arises when the incident electron beam inside the RFEA is focused on the center of a retarding electrode. Comparing I­V curves depending on whether the pre-lens working or not, it is confirmed that the use of the pre-lens dramatically improves the energy resolution and efficiency of the signal acquisition process. The pre-lens RFEA was applied to characterize a Schottky electron gun under various temperatures and extraction voltages as operational conditions. When the tip temperature was increased by 50 K, we were able to measure an energy distribution broadening of 13.8 meV with the proposed pre-lens RFEA. The relative standard deviation of energy distribution was 0.7% for each working condition.

18.
Knee Surg Sports Traumatol Arthrosc ; 30(4): 1257-1265, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33837809

RESUMEN

PURPOSE: The goal of this retrospective observational study is to determine whether patients with and without central sensitization (CS) undergoing total knee arthroplasty (TKA) have similar preoperative expectations. It was hypothesized that the degree of preoperative expectations is higher in patients with CS than in those without. METHODS: The data of 324 patients who underwent primary unilateral TKA for knee osteoarthritis were reviewed and CS was measured using the Central Sensitization Inventory (CSI), which is a validated self-reported questionnaire consisting of a total of 25 questions. CS was defined as a CSI score of 40 or more. Patient expectations were investigated using the Hospital for Special Surgery Knee Replacement Expectations Survey (HSS-KRES) comprising five categories including pain relief, baseline activity, high flexion activity, social activity, and psychological well-being. The expectations of patients, the Western Ontario and McMaster Universities arthritis index (WOMAC) and American Society of Anesthesiologists (ASA) classification scores were compared between the CS and non-CS groups. RESULTS: The top three patient expectations in both groups were pain relief, psychological well-being, and walking ability. The total score for the expectations was 55.0 ± 8.3 in the CS group and 52.3 ± 10.4 in the non-CS group, indicating that the expectations of the CS group were higher than the non-CS group before TKA (p < 0.05). When the items on the HSS-KRES scale and the five categories were compared, the CS group had significantly higher expectations for pain relief and psychological well-being than did the non-CS group (all p < 0.05). CONCLUSION: The expectations of patients with CS before TKA were higher than those without CS. Given the limited improvement in patient-reported outcome measures of patients with CS undergoing TKA, they should be counseled to be realistic especially with their preoperative expectations of pain relief and psychological well-being. LEVEL OF EVIDENCE: III.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Artroplastia de Reemplazo de Rodilla/efectos adversos , Sensibilización del Sistema Nervioso Central , Humanos , Motivación , Osteoartritis de la Rodilla/etiología , Dolor/cirugía , Satisfacción del Paciente , Resultado del Tratamiento
19.
Knee Surg Sports Traumatol Arthrosc ; 30(3): 782-790, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33486560

RESUMEN

PURPOSE: The purpose of this study was to discover whether increased pain sensitivity was associated with postoperative pain and patient-reported outcome measures (PROMs) after total knee arthroplasty (TKA). METHODS: Pain sensitivity was evaluated preoperatively using a pain sensitivity questionnaire (PSQ). Resting, walking, nighttime, and average pain visual analog scale (VAS) were measured before surgery and 6 weeks, 3 months, 6 months, and 1 year after surgery. PROMs were also evaluated based on the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) score and patient satisfaction. The association between pain VAS average score, WOMAC total score, and PSQ score (minor, moderate, and total score) was assessed at each stage. RESULTS: There were 59 patients with a high PSQ score (≥ 5.2) and 53 with a low PSQ score (< 5.2). Up to 1 year postoperatively, the group with high PSQ scores had higher resting, walking, nighttime, and average pain VAS scores than the group with low scores (all p < 0.05). Worse preoperative WOMAC pain, function, and total scores continued until 1 year after surgery in the high-scoring PSQ group (all p < 0.05). The group with low PSQ scores was more satisfied with surgery than the group with high scores (p = 0.027). There was a positive correlation between preoperative PSQ score and pain VAS average score at all time points (all p < 0.05). A relationship between PSQ score and WOMAC total score was also observed (all p < 0.05). CONCLUSION: Increased pain sensitivity is a factor related to higher postoperative pain levels and inferior PROMs in patients undergoing primary TKA. LEVEL OF EVIDENCE: Case-controlled study, III.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Osteoartritis de la Rodilla , Humanos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/cirugía , Dolor Postoperatorio/cirugía , Medición de Resultados Informados por el Paciente , Estudios Retrospectivos , Resultado del Tratamiento
20.
Arch Orthop Trauma Surg ; 142(4): 561-569, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33130934

RESUMEN

PURPOSE: To investigate risk factors and suggest preventive strategy for excessive coronal inclination of tibial plateau following medial opening-wedge high tibial osteotomy (MOWHTO). METHODS: A total of 133 consecutive patients who underwent MOWHTO were retrospectively enrolled. Patients were divided into two groups based on postoperative medial proximal tibial angle (post-MPTA) of 95°: control group (n = 111, 83.5%) with post-MPTA less than 95° and excessive MPTA group (n = 22, 16.5%) with post-MPTA 95° or more. Demographics, radiographic parameters [mechanical lateral distal femoral angle (mLDFA), MPTA, posterior tibial slope, joint line obliquity (JLO), hip-knee-ankle angle, joint line convergence angle (JLCA), weight bearing line ratio, and correction angle], and clinical outcomes of patients were compared. Multiple logistic regression analysis was performed to determine risk factors for post-MPTA 95° or more. RESULTS: Multiple logistic regression analysis showed that preoperative JLO ≥ 3° [odds ratio (OR) 6.940, 95% confidence interval (CI) 2.373-20.296, p < 0.001] and preoperative JLCA ≥ 5° (OR 5.723, 95% CI 1.833-17.865, p = 0.008) were statistically significant risk factors for post-MPTA ≥ 95°. Incidences of excessive MPTA following MOWHTO in patients with none, one, and two risk factors preoperatively were 3.7%, 26.7%, and 77.8%, respectively. CONCLUSION: Preoperative JLO ≥ 3° and JLCA ≥ 5° were two significant risk factors for excessive MPTA following MOWHTO. Thus, surgeon should consider other types of osteotomy if these two risk factors are present together preoperatively in MOWHTO candidates. LEVEL OF EVIDENCE: Level III.


Asunto(s)
Osteoartritis de la Rodilla , Humanos , Articulación de la Rodilla/cirugía , Osteoartritis de la Rodilla/cirugía , Osteotomía , Estudios Retrospectivos , Factores de Riesgo , Tibia/cirugía
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