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1.
Angew Chem Int Ed Engl ; : e202407766, 2024 May 22.
Artículo en Inglés | MEDLINE | ID: mdl-38778504

RESUMEN

Inverted perovskite solar cells (PSCs) are preferred for tandem applications due to their superior compatibility with diverse bottom solar cells. However, the solution processing and low formation energy of perovskites inevitably lead to numerous defects at both the bulk and interfaces. We report a facile and effective strategy for precisely modulating the perovskite by incorporating AlOx deposited by atomic layer deposition (ALD) on the top interface. We find that Al3+ can not only infiltrate the bulk phase and interact with halide ions to suppress ion migration and phase separation but also regulate the arrangement of energy levels and passivate defects on the perovskite surface and grain boundaries. Additionally, ALD-AlOx exhibits an encapsulation effect through a dense interlayer. Consequently, the ALD-AlOx treatment can significantly improve the power conversion efficiency (PCE) to 21.80 % for 1.66 electron volt (eV) PSCs. A monolithic perovskite-silicon TSCs using AlOx-modified perovskite achieved a PCE of 28.5 % with excellent photothermal stability. More importantly, the resulting 1.55 eV PSC and module achieved a PCE of 25.08 % (0.04 cm2) and 21.01 % (aperture area of 15.5 cm2), respectively. Our study provides an effective way to efficient and stable wide-band gap perovskite for perovskite-silicon TSCs and paves the way for large-area inverted PSCs.

2.
J Pediatr Orthop ; 44(7): e580-e587, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38676464

RESUMEN

OBJECTIVES: To assess the treatment and outcomes of supracondylar humeral fractures (SHFs) in children older than 10 years of age at the time of injury. METHODS: The study analyzed clinical data from 60 patients who sustained SHF, all over the age of 10 years, were analyzed. The patients included 49 males and 11 females with a mean age of 10.9 ± 0.9 years (range, 10 to 14.5). All patients underwent surgical treatment under general anesthesia. Closed reduction (CR) and percutaneous fixation were the primary treatment, with open reduction and internal fixation being employed only in cases CR was unsuccessful. The study assessed the healing of fractures by measuring the radiographic angles, including the carrying angle (RCA), Baumann's angle (BA), and metaphyseal-diaphyseal angle (MDA) on anteroposterior radiographs of the elbow joint. In addition, the study evaluated whether the anterior humeral line (AHL) appropriately passed through the middle third of the capitellum. The final follow-up visit used the Mayo Elbow Performance Index score (MEPI) and Flynn's criteria to analyze the recovery of elbow function. RESULTS: There were 15 (25%) SHF type II, 17 (28.3%) type III and 28 (46.7%) type IV. Of the 60 patients, 56 (93.3%) underwent successful CR, whereas 4 (6.7%) required open reduction and internal fixation because of an unsuccessful CR. The final follow-up showed the average BA as 72° ± 5.3°, the average MDA as 88.3° ± 2.8°, and the average RCA as 9.6° ± 3.9°. The AHL bisected accurately the capitellum in 59 cases (98.3%). The average range of elbow flexion-extension was 146.6° ± 8.6°, whereas the average MEPI score was 99.9 ± 0.6; 98.3% (n=59) were rated as excellent and 1.7% (n=1) were rated as good. According to Flynn's criteria, 86.7% had an excellent outcome (n=52), 10% had a good outcome (n=6), and 3.3% had a poor outcome (n=2). Only 1 patient (1.7%) experienced redisplacement. Eight cases of nerve injury were reported, with 7 involving the radial nerve and 1 involving the ulnar nerve; all resolved spontaneously. CONCLUSIONS: CR and percutaneous fixation have been shown to be effective in treating SHF in 93.3% of children aged 10 years old and older at the time of injury, with favorable radiographic and functional outcomes and a low risk of secondary displacement. Open reduction should only be considered when CR is ineffective.


Asunto(s)
Fijación Interna de Fracturas , Fracturas del Húmero , Humanos , Fracturas del Húmero/cirugía , Fracturas del Húmero/diagnóstico por imagen , Masculino , Femenino , Niño , Resultado del Tratamiento , Adolescente , Estudios Retrospectivos , Fijación Interna de Fracturas/métodos , Estudios de Seguimiento , Articulación del Codo/cirugía , Articulación del Codo/diagnóstico por imagen , Rango del Movimiento Articular , Curación de Fractura , Radiografía , Reducción Abierta/métodos
3.
IEEE Trans Image Process ; 32: 3507-3520, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37335800

RESUMEN

Recognizing human actions in dark videos is a useful yet challenging visual task in reality. Existing augmentation-based methods separate action recognition and dark enhancement in a two-stage pipeline, which leads to inconsistently learning of temporal representation for action recognition. To address this issue, we propose a novel end-to-end framework termed Dark Temporal Consistency Model (DTCM), which is able to jointly optimize dark enhancement and action recognition, and force the temporal consistency to guide downstream dark feature learning. Specifically, DTCM cascades the action classification head with the dark augmentation network to perform dark video action recognition in a one-stage pipeline. Our explored spatio-temporal consistency loss, which utilizes the RGB-Difference of dark video frames to encourage temporal coherence of the enhanced video frames, is effective for boosting spatio-temporal representation learning. Extensive experiments demonstrated that our DTCM has remarkable performance: 1) Competitive accuracy, which outperforms the state-of-the-arts on the ARID dataset by 2.32% and the UAVHuman-Fisheye dataset by 4.19% in accuracy, respectively; 2) High efficiency, which surpasses the current most advanced method (Chen et al., 2021) with only 6.4% GFLOPs and 71.3% number of parameters; 3) Strong generalization, which can be used in various action recognition methods (e.g., TSM, I3D, 3D-ResNext-101, Video-Swin) to promote their performance significantly.


Asunto(s)
Algoritmos , Reconocimiento de Normas Patrones Automatizadas , Humanos , Grabación en Video , Reconocimiento de Normas Patrones Automatizadas/métodos , Aprendizaje , Actividades Humanas
4.
Front Pediatr ; 11: 1286662, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38283404

RESUMEN

Objective: This study aimed (i) to evaluate the radiographic characteristics of patients with congenital thumb duplication (CTD) type C2 according to the classification of Wu et al., (ii) to describe the various subtypes of type C2 CTD, and (iii) to propose a classification system that allows the identification of different surgical strategies based on the radiographic anatomy of this specific subtype of duplication. Methods: We retrospectively reviewed 92 patients (92 thumbs) with type C2 CTD according to the Wu et al. classification in our institution between August 2015 and April 2021. All CTDs were classified according to the interphalangeal joint alignment of the main thumb at the posteroanterior radiograph of the thumb before operation: type I (no deviation), type II (ulnar deviation), and type III (radial deviation). Results: All CTDs (n = 92) could be classified according to the proposed classification system: 76 (82.6%) were type I, 10 (10.9%) were type II, and six were type III (6.5%). According to the Kim system of subtype classification, there were 55 (59.8%) type 1, 24 (26.1%) type 2, and 13 (14.1%) type 3 cases. Conclusions: The suggested classification completes the Wu et al. system and has the potential to guide surgical treatment in children with type C2 CTD. Level of evidence: III.

5.
Front Pediatr ; 10: 1027243, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36405832

RESUMEN

Objective: The objective of this study was to evaluate epidemiological and anatomical characteristics of children with congenital thumb duplication (CTD). Methods: We retrospectively reviewed 2108 children with CTD. Data regarding sex, age at the surgery, laterality, uni- or bilateral involvement, and dominant side were retrieved from the medical charts. Plain radiographs were used to classify all CTD according to Wassel-Flatt, Rotterdam and Chung classification systems and to evaluate the patho-anatomy of the duplication as well as the presence of associated anomaly. Results: A total of 796 girls and 1,312 boys with CTD (n = 2,300 thumbs) met the inclusion criteria. The male to female and unilateral to bilateral ratio were 1.6:1 and 10:1, respectively. Associated anomaly was found in 238/2108 patients (11.3%), and the middle phalanx deformity of the 5th finger was the most common one. A dominant thumb, larger and more developed, was on the ulnar side in 2270/2,300 cases (98.7%).According to the Wassel-Flatt classification, type IV (40.2%) was the most common deformity and the extra thumb was connected to the main thumb by a joint in most cases (437/780); overall, 15.7% of thumbs (n = 360) did not fit the Wassel-Flatt classification.According to the Rotterdam classification, type IV (51.3%) was the most common form; in most cases (363/1180) the thumb was hypoplastic or floating. Overall, 3/2,300 thumbs (0.1%) could not be classified according to Rotterdam classification.According to the Chung classification, type A was the most common subtype (44.1%); in most cases (716/1015) the duplication was at the level of the metacarpal bone. Overall, 2/2,300 thumbs (0.1%) did not fit the Chung classification. Conclusions: In patients from southern China, CTD shows male and right-sided predominance with ulnar-dominant thumb. Abnormalities of the middle phalanx of the 5th finger are more frequent in patients with associated anomaly. The development of a simple and comprehensive classification system is needed to guide treatment and to adequately assess the epidemiological characteristics of patients with CTD in order to facilitate comparison between different patients' populations. Level of evidence: III.

7.
J Hand Surg Am ; 2022 Aug 05.
Artículo en Inglés | MEDLINE | ID: mdl-35940999

RESUMEN

PURPOSE: The objectives of this study were to (1) evaluate the radiographic characteristics of children with congenital thumb duplication (CTD) seen in our institution between August 2015 and April 2021; (2) introduce a modified radiographic classification system (MCS) capable of including all cases of CTD based on their radiographic pathoanatomy; and (3) evaluate the inter- and intrarater reliability of the new classification system. METHODS: We retrospectively reviewed 2,108 patients with 2,300 CTDs. The MCS is based on the Wassel-Flatt and Chung et al classification systems and includes specific subtypes from the Rotterdam and modified Wassel-Flatt classifications. The MCS is characterized by 4 groups according to the anatomical morphology of the duplication: A (joint), B (epiphysis), C (bone), and D (soft tissues). Each group includes 4 subtypes according to the location of the CTD, with subtypes 1-3 extending from the distal phalanx to the metacarpal or interphalangeal joints, then to the carpometacarpal joint, and with subtype 4 only including the triphalangia of the main thumb. RESULTS: Among the 2,300 fingers, 360 (15.7%), 2 (0.1%), and 3 (0.1%) CTDs could not be classified according to the Wassel-Flatt, Chung et al, and Rotterdam classifications, respectively. According to the MCS, the 2 most common forms of CTD were A2 (680/2,300; 29.6%) and D2 (308/2,300; 13.4%). All cases could be classified according to this classification system. The MCS showed excellent intrarater (0.875) and interrater (0.851) reliability relative to the Wassel-Flatt (0.863 and 0.820, respectively), Chung et al (0.793 and 0.822, respectively), and Rotterdam (0.873 and 0.836, respectively) systems. CONCLUSIONS: The MCS is a potential radiographic classification for CTD that enables the classification of all patients and has excellent inter- and intrarater reliability. CLINICAL RELEVANCE: Existing classification systems do not allow classification of the full spectrum of CTD and are not always related to surgery, and some existing systems are complex, with many categories that are rarely encountered, or are difficult to use widely in clinical practice.

8.
IEEE Trans Image Process ; 31: 4104-4116, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35687626

RESUMEN

Action visual tempo characterizes the dynamics and the temporal scale of an action, which is helpful to distinguish human actions that share high similarities in visual dynamics and appearance. Previous methods capture the visual tempo either by sampling raw videos with multiple rates, which require a costly multi-layer network to handle each rate, or by hierarchically sampling backbone features, which rely heavily on high-level features that miss fine-grained temporal dynamics. In this work, we propose a Temporal Correlation Module (TCM), which can be easily embedded into the current action recognition backbones in a plug-in-and-play manner, to extract action visual tempo from low-level backbone features at single-layer remarkably. Specifically, our TCM contains two main components: a Multi-scale Temporal Dynamics Module (MTDM) and a Temporal Attention Module (TAM). MTDM applies a correlation operation to learn pixel-wise fine-grained temporal dynamics for both fast-tempo and slow-tempo. TAM adaptively emphasizes expressive features and suppresses inessential ones via analyzing the global information across various tempos. Extensive experiments conducted on several action recognition benchmarks, e.g. Something-Something V1&V2, Kinetics-400, UCF-101, and HMDB-51, have demonstrated that the proposed TCM is effective to promote the performance of the existing video-based action recognition models for a large margin. The source code is publicly released at https://github.com/zphyix/TCM.


Asunto(s)
Actividades Humanas , Programas Informáticos , Humanos
9.
Children (Basel) ; 9(5)2022 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-35626929

RESUMEN

Background: To analyze the clinical data of patients aged < 6 months with developmental dislocation of the hip (DDH) treated with Pavlik Harness (PH) in order to identify the best time to terminate PH treatment. Method: Fifty-four patients (47 females, 7 males; 63 hips) met the inclusion criteria and were included in the study; there were 33 (61.1%) left, 12 (22.2%) right and 9 (16.7%) bilateral DDH. The mean age at diagnosis was 11.8 ± 5.9 weeks (range, 1.4−25.5). All patients underwent fulltime PH treatment for about three months. At completion of PH treatment, patients were then divided into Group A, including patients with clinically stable hip joint and Graf type-I hip on ultrasound (US), and Group B, including patients with clinically stable hip joint and well-reduced hip on anterior-posterior (AP) radiographs without acetabular dysplasia. Six months after completion of PH treatment, the presence/absence of residual acetabular dysplasia (RAD) was evaluated on AP pelvis radiographs. The t-test and chi-square test were used to compare the differences in age, gender, side, Graf classification and RAD rate between the two groups of patients. Results: At completion of PH treatment, 45 hips were in Group A and 18 in Group B. There were no significant differences in age, gender, side, preoperative alpha angle and Graf classification between the two groups. Six months after discontinuation of PH, the AI in Group A (27.1° ± 6.8°) was significantly higher than that in Group B (21.9° ± 3.5°; p = 0.001); moreover 23 hips (51.1%) in Group A developed RAD compared to one hip in Group B (5.6%; p = 0.001). Among Group A patients, those with RAD were significantly older (13.7 ± 4.9 weeks) than those with normal hips (7.6 ± 3.8 weeks; p < 0.001); the incidence of RAD was significantly lower in patients with Graf type-II D hips (22.2%) than in patients with Graf type-III (70%) and type-IV hips (71.4%; p = 0.006). However, logistic regression analysis identified age as the only risk factor for RAD. All 24 hips with RAD (24/63, 38.1%) were treated with abduction braces. At final follow-up, AI in Group A (20.5° ± 3.3°) was not significantly different from that in Group B (21.9° ± 3.3°; p = 0.132). At the last follow-up visit, five hips (11.1%) in Group A still had RAD, compared to none in Group B (p = 0.31). Conclusions: In patients with DDH treated by PH, Graf type-I on US is not an absolute timing to terminate PH treatment. In addition, patients ≥ 13 weeks had a high risk of RAD despite PH treatment as 51.1% of infants developed RAD during follow up. Follow-up radiographs should be requested in all patients achieving Graf type-I hips at completion of PH treatment.

10.
J Child Orthop ; 16(1): 35-45, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35615392

RESUMEN

Purpose: To investigate the value of antero-posterior and lateral radiographs in predicting clubfoot relapse after treatment with the Ponseti method. Methods: This was a retrospective review of 104 children (157 feet) younger than 3 months of age with idiopathic clubfoot treated using the Ponseti method at our institution between January 2007 and December 2014. All patients underwent Achilles tenotomy and were divided into two groups according to the need for further surgery to correct the deformity: relapsed group (24 patients; 36 feet) and non-relapsed group (80 patients; 121 feet). All antero-posterior and lateral foot radiographs were performed less than 3 months after Achilles tenotomy. The talo-calcaneal (TC-AP) and talus-first metatarsal (TM-AP) angles were measured in the antero-posterior view, while the tibio-calcaneal (TIC-L), talus-first metatarsal (TM-L), and talo-calcaneal (TC-L) angles were measured in the lateral view. The multi-factor logistic regression model of the stepwise selection method was used to predict the relapse of clubfoot deformity from the potential predictive values. Results: The mean age at initial plain radiography examination was 99.45 ± 21.54 days. Differences in TC-AP, TM-AP, TC-L, and TIC-L between the two groups were statistically significant. However, only TM-AP and TIC-L were included in the "risk of relapse" formula using the multi-factor logistic stepwise selection method. Conclusion: Early antero-posterior and lateral radiographs in children younger than 3 months of age at initial Ponseti treatment have positive predictive value for relapse. Reduced TM-AP angle and increased TIC-L were associated with an increased risk of relapse. Level of evidence: level III.

11.
J Pediatr Orthop B ; 31(4): 397-406, 2022 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34908029

RESUMEN

This study was aimed to evaluate the kinetics and kinematics of the foot and ankle using three-dimensional gait analysis in children with recurrent clubfoot treated with tibialis anterior tendon transfer (TATT). Three-dimensional gait analysis of 17 children with dynamic supination (24 feet; 12 males; mean age: 6.34 years) was performed pre- and post-TATT. Spatial, temporal and kinematic parameters, as well as the gait deviation index (GDI), were recorded for all patients. Moreover, to evaluate the severity of dynamic supination during walking, we also measured the angle between the plane of the foot and the X-axis during the swing phase (V-angle-S). The postoperative step length (38.95 ± 8.36 cm) and stride length (76.73 ± 15.92 cm) were significantly smaller than their preoperative values (40.68 ± 9.35 cm and 80.57 ± 17.51 cm; P = 0.0316 and P = 0.0028, respectively). The postoperative peak internal ankle rotation angle in the frontal plane (20.45° ± 14.44) was significantly lower than the preoperative value (25.93° ± 9.84; P = 0.029). The postoperative peak internal foot progression angle in the transverse plane (0.96° ± 5.83) was significantly lower than the preoperative value (4.34° ± 8.88; P = 0.026). However, both the peak ankle varus moment and GDI were not significantly different between the pre- and postoperative data. Postoperative V-angle-S values (28.55° ± 7.56) were reduced compared to their preoperative values (32.52° ± 6.53; P = 0.0094). TATT to the lateral cuneiform can correct dynamic supination in patients with a recurrent clubfoot; however, it has limited or no effects on hindfoot varus deformity. Level of evidence: Level III.


Asunto(s)
Pie Equinovaro , Tobillo , Fenómenos Biomecánicos , Niño , Pie Equinovaro/cirugía , Marcha , Análisis de la Marcha , Humanos , Masculino , Recurrencia , Transferencia Tendinosa/métodos
13.
Dalton Trans ; 49(22): 7620-7627, 2020 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-32432280

RESUMEN

A series of mononuclear seven-coordinate Co(ii) complexes [CoII(BPA-TPA)](ClO4)2·H2O (2-ClO4), [CoII(BPA-TPA)](PF6)2 (3-PF6) and [CoII(BPA-TPA)](BPh4)2 (4-BPh4) have been synthesized based on the ligand 2,6-bis(bis(2-pyridylmethyl)amino)methylpyridine (BPA-TPA), and their structures have been characterized by single-crystal X-ray diffraction. All these complexes feature an intermediate coordination polyhedron between a capped trigonal prism and a capped octahedron, which is perturbed by the variation of the counter anions. Easy-plane magnetic anisotropies for all complexes were revealed via the analyses of the direct-current magnetic data and high-field electron paramagnetic resonance (HFEPR) spectra. They show slow magnetic relaxation under applied direct current field, which is similar to the previously reported complex [CoII(BPA-TPA)](BF4)2 (1-BF4) with a capped trigonal prism. This work provides a new example of modulating the properties of single-ion magnets (SIMs) by changing the counter anions.

14.
J Pediatr Orthop B ; 29(5): 431-437, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-31464797

RESUMEN

This study aimed to investigate the effect of age on the rates of redislocation, avascular necrosis (AVN) of the femoral head, and final radiographic outcomes in patients with developmental dysplasia of the hip (DDH) treated with closed reduction. A total of 308 hips (276 patients) with DDH treated with closed reduction were included and divided into three groups according to age (<12, 12-18, 18-24 months). Tönnis grade, rate of redislocation and AVN, Severin radiographic grade, and risk of surgery were evaluated on radiographs. Tönnis grade significantly increased with age (P < 0.001). Redislocation occurred in 17 (5.5%) and AVN occurred in 36 (11.7%) hips. The rate of redislocation and AVN was similar among the three age groups in all Tönnis grades. However, redislocation rate significantly increased with Tönnis grade (P = 0.027). Overall, 246 hips (79.9%) had satisfactory final outcomes, and 62 hips (20.1%) had unsatisfactory outcome; no difference was observed among three age groups. A total of 103 hips (33.4%) were found to be at risk for secondary surgery. The surgical risk (25%) in patients younger than 12 months was lower than that of older patients (12-18 months: 34.4%; 18-24 months: 37.9%). Logistic regression analysis also confirmed that age was not a risk factor for redislocation, AVN, or poor radiographic outcome. In conclusion, age has no significant impact on redislocation and AVN in patients aged 6-24 months with DDH treated by closed reduction. Although older patients have a higher risk developing residual acetabular dysplasia, secondary pelvic surgery provides favorable outcomes in most patients.


Asunto(s)
Displasia del Desarrollo de la Cadera/cirugía , Necrosis de la Cabeza Femoral/etiología , Luxación de la Cadera/etiología , Preescolar , Displasia del Desarrollo de la Cadera/diagnóstico por imagen , Femenino , Humanos , Lactante , Masculino , Procedimientos Ortopédicos , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Riesgo , Índice de Severidad de la Enfermedad
15.
Foot Ankle Int ; 41(3): 350-355, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31855081

RESUMEN

BACKGROUND: Percutaneous Achilles tenotomy (PAT) is an important component of the Ponseti method and is performed in 85% to 90% of patients. However, there is a lack of objective data assessing early radiographic changes in children undergoing PAT. METHODS: Forty-nine patients with idiopathic clubfoot treated by Ponseti casting were prospectively enrolled between October 2017 and October 2018. Preoperative and postoperative ankle dorsiflexion (pre-ADFmax, post-ADFmax) and lateral talocalcaneal angle (pre-LTCAmax, post-LTCAmax) values with the ankle in maximal dorsiflexion as well as postoperative LTCA values with the ankle in the neutral position (post-LTCAneutral) were measured. The relationship between the preoperative and postoperative ADF and LTCA values was studied using Pearson or Spearman correlation coefficients. Forty-nine patients (72 feet) were included; the mean age at initial treatment was 32.2 ± 24.1 days. RESULTS: Post-LTCAmax improved significantly from 18.6 ± 9.2 degrees to 25.1 ± 10.5 degrees (P < .0001). Pre-ADF and pre-LTCAmax showed a positive correlation in both the less than 28-day group (r = 0.42; P = .015) and the Dimeglio III group (r = 0.29; P = .035). However, post-ADF and post-LTCAmax showed a positive correlation in the Dimeglio III group (r = 0.30; P = .028). The degree of improvement in post-LCTAmax in the Dimeglio III group was similar to that in the Dimeglio IV group (P = .28). CONCLUSION: The LTCA increased immediately after PAT in clubfoot, although the improvement seemed to be unrelated to the severity of the disease. PAT led to an increase in both ADF and the LTCA, and it contributed to the improvements in subtalar joint motion and alignment. LEVEL OF EVIDENCE: Level III, comparative study.


Asunto(s)
Tendón Calcáneo/diagnóstico por imagen , Tendón Calcáneo/cirugía , Moldes Quirúrgicos , Pie Equinovaro/diagnóstico por imagen , Pie Equinovaro/cirugía , Articulación Talocalcánea/diagnóstico por imagen , Tenotomía/métodos , Femenino , Humanos , Lactante , Masculino , Radiografía , Rango del Movimiento Articular
16.
J Cell Biochem ; 120(3): 2886-2896, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-29266342

RESUMEN

Neurofibromatosis type I (NF1), which is caused by mutations in the NF1 gene, is a common autosomal dominant genetic disease leading to skeletal abnormalities. Both NF1 gene and mammalian target of rapamycin complex 1 (mTORC1) signaling are associated with the osteogenic differentiation of bone marrow stem cells (BMSCs). In this study, we hypothesized that mTORC1 signaling is involved in NF1-modulated osteoblast differentiation of BMSCs. Human BMSCs were cultured in an osteogenic induction medium. The expression of NF1 was either inhibited or overexpressed by transfecting NF1 with a specific small interfering RNA (siRNA) or pcDNA3.0 plasmid, respectively. In addition, an mTORC1 signaling inhibitor and agonist were used to investigate the effects of mTORC1 on NF1-modulated osteogenic differentiation of BMSCs. The results indicated that inhibiting the expression of NF1 with siRNA significantly decreased the mRNA levels of NF1, whereas overexpressing the expression of NF1 with pcDNA3.0 plasmid significantly increased the mRNA levels of NF1 at days 3, 7, 14 and 21 after culture. We observed reduced osteogenic differentiation and cell proliferation in the NF1-siRNA group and enhanced osteogenic differentiation and cell proliferation of BMSCs in the NF1-pcDNA3.0 group. The activity of mTORC1 signaling (p-mTORC1, p-S6K1, and p-4EBP1) was significantly upregulated in the NF1-siRNA group and significantly inhibited in the NF1-pcDNA3.0 group, 7 and 14 days after culture. The effects of NF1-siRNA and NF1-pcDNA3.0 on osteogenic differentiation of BMSCs and cell proliferation were reversed by mTORC1 inhibitor and agonist, respectively. In conclusion, NF1 modulates osteogenic differentiation and cell proliferation of human BMSCs and mTORC1 signaling is essential for this process.


Asunto(s)
Diana Mecanicista del Complejo 1 de la Rapamicina/metabolismo , Células Madre Mesenquimatosas/citología , Neurofibromina 1/genética , Osteogénesis , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Células Cultivadas , Regulación de la Expresión Génica/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/metabolismo , Morfolinas/farmacología , Neurofibromina 1/antagonistas & inhibidores , Neurofibromina 1/metabolismo , Pirimidinas/farmacología , ARN Interferente Pequeño/farmacología , Transducción de Señal/efectos de los fármacos
17.
Eur J Orthop Surg Traumatol ; 29(1): 51-57, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30076476

RESUMEN

BACKGROUND: Closed reduction and spica cast is still the preferred treatment option for children presenting with developmental dysplasia of the hip (DDH) after the age of 6 months. This study aims to investigate the outcomes of patients with DDH treated by closed reduction and dynamic cast immobilization. METHODS: In total, 159 patients (mean age 15.6 ± 4.2 months; 172 hips) were treated with a dynamic cast immobilization for 3 months, followed by an abduction brace until a stable concentric reduction was achieved. Radiological examination was performed at each follow-up visit to assess reduction, redislocation rate and presence of avascular necrosis (AVN) of the femoral epiphysis. Final radiographic results were evaluated with the Severin classification. RESULTS: The redislocation rate was 4.1% (7/172); the overall AVN rate was 14.5% (grade II: 16 hips; grade III: 5 hips; grade IV: 3 hips). At last follow-up visit, the mean age of patients was 61.6 ± 21.3 months (range 30.8-141), and the mean acetabular index was 22.6° ± 5.6°; 67.3% of the hips had Severin type I radiographic criteria, 8.5% had type II, 23.6% had type III, and 0.6% had type IV. CONCLUSIONS: Dynamic cast is an alternative to spica cast immobilization in DDH patients undergoing closed reduction. It has similar redislocation and AVN rates compared to standard spica cast immobilization, as reported by previous studies.


Asunto(s)
Moldes Quirúrgicos , Luxación Congénita de la Cadera/terapia , Inmovilización/métodos , Tirantes , Moldes Quirúrgicos/efectos adversos , Preescolar , Femenino , Necrosis de la Cabeza Femoral/diagnóstico por imagen , Necrosis de la Cabeza Femoral/etiología , Estudios de Seguimiento , Luxación Congénita de la Cadera/complicaciones , Luxación Congénita de la Cadera/diagnóstico por imagen , Humanos , Inmovilización/efectos adversos , Lactante , Masculino , Recurrencia , Piel/lesiones , Enfermedades Cutáneas Infecciosas/etiología , Resultado del Tratamiento
18.
Int Orthop ; 42(12): 2961-2968, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29687316

RESUMEN

INTRODUCTION: Bernese-type triple pelvic osteotomy (BTPO) combines periacetabular and triple innominate osteotomy techniques. However, studies that evaluate the clinical and radiographic outcomes of BTPO are scarce. The aim of this study is to report on the clinical and radiographic outcomes of ambulatory children with developmental dysplasia of the hip (DDH) or Legg-Calvé-Perthes disease (LCPD) managed with BTPO that were older than five years of age at the time of surgery. MATERIALS AND METHODS: We retrospectively reviewed the records of 27 consecutive patients with DDH or LCPD (mean age 7.6 ± 1.8; 28 hips) who were treated with the reported technique. All patients had regular clinical and radiographic follow-up. Post-operatively, changes in the acetabular index (AI) and centre-edge angle of Wiberg (CEA) were measured in all patients. The presence/absence of avascular necrosis of the femoral epiphysis was also noted in patients with DDH. Final radiographic results were evaluated with the Severin and Stulberg classifications. The Harris hip score was used in the functional evaluation of all patients. RESULTS: In patients with DDH, the mean age at the time of surgery was 7.5 ± 1.8 years and the mean follow-up time was 22.2 ± 10.7 months. Prior to surgery, the mean AI was 37.9° ± 7.6°. At their final follow-up visit, the mean AI and CEA were 10.8° ± 5.4° and 40.9° ± 8.6°, respectively. Moreover, 66.7% of hips (14/21) were graded as Severin type I, and 33.3% (7/21) were graded as type II. The overall AVN rate was 14.3% (3/21). The mean Harris score was 92.1 ± 7.7. In patients with LCPD, the mean age at the time of surgery was 7.9 ± 1.8 years, and the mean follow-up time was 18.4 ± 6.1 months. Prior to surgery, 85.7% of hips were graded as Herring C, and 14.3% were graded as grade B. Prior to surgery, the mean AI and CEA were 19.4° ± 5.3° and 19.1° ± 12.6°, respectively. At the final follow-up visit, the mean AI and CEA were 5.8° ± 3.4° and 50.3° ± 12.0°, respectively, and 57.1% of hips were graded as Stulberg II. The mean Harris score was 94 ± 5.4. Ischial osteotomy non-unions were recorded in three patients (10.7%). CONCLUSIONS: BTPO through a modified anterior Smith-Peterson approach is an alternative treatment for DDH and LCPD in older children who are skeletally immature. It not only provides for a large acetabular correction but also achieves good biomechanical stability.


Asunto(s)
Luxación Congénita de la Cadera/cirugía , Enfermedad de Legg-Calve-Perthes/cirugía , Osteotomía , Acetábulo/cirugía , Anciano , Niño , Preescolar , Femenino , Fémur/cirugía , Humanos , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
19.
Int Orthop ; 42(3): 631-640, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29285666

RESUMEN

PURPOSE: Our objective was to find the best predictor of late residual acetabular dysplasia in developmental dysplasia of the hip (DDH) after closed reduction (CR) and discuss the indications for secondary surgery. METHODS: We retrospectively reviewed the records of 89 patients with DDH (mean age 16.1 ± 4.6 months; 99 hips) who were treated by CR. Hips were divided into three groups according to final outcomes: satisfactory, unsatisfactory and operation. The changes in the acetabular index (AI), centre-edge angle of Wiberg (CEA), Reimer's index (RI) and centre-head distance discrepancy (CHDD) over time among groups were compared. The power of predictors for late residual acetabular dysplasia of AI, CEA, RI and CHDD at different time points was analysed by logistic regression analysis. Receiver operating characteristics (ROC) curve analysis was used to determine cutoff values and corresponding sensitivity, specificity and diagnostic accuracy for these parameters. RESULTS: Both AI and CEA improved in all groups of patients following CR. In the satisfactory group, AI progressively decreased until seven to eight years, while CEA increased until nine to ten years (P < 0.05). In the unsatisfactory group, AI and CEA ceased to improve three and two years after CR, respectively (P < 0.05). CEA and RI were significantly better in the satisfactory group compared with the unsatisfactory group at all time points (P < 0.05). Following CR, both RI and CHDD remained stable over time in all groups. Final outcome following CR could be predicted by AI, CEA and RI at all time points (P < 0.01). Cutoff values of AI, CEA and RI were 28.4°, 13.9° and 34.5%, respectively, at one year and 25°, 20° and 27%, respectively, at two to four years post-CR. A total of 80-88% of hips had an unsatisfactory outcome if AI > 28.4° and >25 at one and two to four years following CR, respectively. However, if CEA was less than or RI was larger than the cutoff values at each time point, only 40-60% of hips had an unsatisfactory outcome. Mean sensitivity (0.889), specificity (0.933) and diagnostic accuracy (92.1%) of AI to predict an unsatisfactory outcome were significantly better compared with CEA (0.731; 0.904; 78.2%) and RI (0.8; 0.655; 70.8%) (P < 0.05). CONCLUSIONS: Satisfactory and unsatisfactory hips show different patterns of acetabular development after reduction. AI, CEA and RI are all predictors of final radiographic outcomes in DDH treated by CR, although AI showed the best results. AI continues to improve until seven years after CR in hips with satisfactory outcomes, while it ceases to improve three to four years after CR in hips with unsatisfactory outcomes. According to our results, surgery is indicated if AI >28° 1 year following CR or AI >25° two to four years after CR. CEA and RI should be used as a secondary index to aid in the selection of patients requiring surgery.


Asunto(s)
Acetábulo/diagnóstico por imagen , Enfermedades del Desarrollo Óseo/diagnóstico por imagen , Luxación Congénita de la Cadera/diagnóstico por imagen , Luxación Congénita de la Cadera/terapia , Manipulación Ortopédica , Acetábulo/patología , Enfermedades del Desarrollo Óseo/etiología , Enfermedades del Desarrollo Óseo/patología , Moldes Quirúrgicos , Femenino , Humanos , Lactante , Masculino , Estudios Retrospectivos , Resultado del Tratamiento
20.
Zhonghua Nan Ke Xue ; 23(1): 21-26, 2017 Jan.
Artículo en Chino | MEDLINE | ID: mdl-29658232

RESUMEN

OBJECTIVE: To observe the effects of swimming plus medication on the expressions of cytokines in rats with chronic abacterial prostatitis (CAP). METHODS: Forty healthy adult male SD rats were randomly divided into five groups of equal number, normal control, CAP model control, medication, exercise therapy, and exercise + medication. The CAP model was made by Xiaozhiling injection, and at 7 days after modeling, the rats in the medication and exercise + medication groups were treated intragastrically with Qianlie Shutong Capsules (0.016 g/ml) at 20 ml per kg of the body weight qd, those in the exercise therapy and exercise + medication groups were made swim at a regular time once a day, 35 minutes on the first day and 5 minutes more on the second until 50 minutes once, for 4 successive weeks, and those in the normal control, model control and exercise therapy groups received normal saline only. After 14 and 28 days of treatment, all the rats were killed and their prostates harvested for observation of histopathological changes and determination of the expressions of TNF- α, IL-1ß and IL-6 in the prostatic tissue homogenate by ELISA. RESULTS: After 14 days of treatment, the expression levels of TNF-α, IL-1ß and IL-6 were significantly elevated in the groups of CAP model control (ï¼»183.08±8.07ï¼½ pg/ml, ï¼»57.55±3.53ï¼½ pg/ml and ï¼»256.15±13.95ï¼½ ng/L), medication (ï¼»118.49±8.06ï¼½ pg/ml, ï¼»42.64±4.64 ï¼½ pg/ml and ï¼»200.74±9.33ï¼½ ng/L), exercise therapy (ï¼»169.63±10.64ï¼½ pg/ml, ï¼»50.45±5.71ï¼½ pg/ml and ï¼»245.23±6.49ï¼½ ng/L), and exercise + medication (ï¼»107.82±7.81ï¼½ pg/ml, ï¼»40.35±6.93ï¼½ pg/ml and ï¼»187.04±10.85ï¼½ ng/L) as compared with those in the normal control (ï¼»20.36±1.82ï¼½ pg/ml, ï¼»14.64±1.91ï¼½ pg/ml and ï¼»70.58±2.09ï¼½ ng/L) (P<0.05). At 28 days, the levels of TNF- α, IL-1ß, IL-6 were remarkably lower in the exercise + medication group (ï¼»29.30±3.78ï¼½ pg/ml, ï¼»16.91±1.24ï¼½ pg/ml and ï¼» 88.65±6.74ï¼½ ng/L) than in the medication group (ï¼»39.67±3.19ï¼½ pg/ml, ï¼»26.27±3.49ï¼½ pg/ml and ï¼»110.26±6.33ï¼½ ng/L) (P<0.05) and close to those of the normal control group (ï¼»19.34±1.76ï¼½ pg/ml, ï¼»13.68±1.06ï¼½ pg/ml and ï¼»71.34±2.50ï¼½ ng/L). During the treatment, no obvious pathological changes were found in the prostate tissue of the normal control rats, while significant chronic prostatic inflammation was observed in the CAP models, and the inflammation was relieved in different degrees after intervention, most significantly in the exercise + medication group. CONCLUSIONS: Swimming can relieve prostatic inflammation and swimming plus medication can effectively reduce the expressions of cytokines and alleviate histological damage in the prostatic tissue of CAP rats.


Asunto(s)
Medicamentos Herbarios Chinos/uso terapéutico , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Prostatitis/metabolismo , Natación , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Enfermedad Crónica , Terapia Combinada/métodos , Citocinas/metabolismo , Masculino , Condicionamiento Físico Animal , Prostatitis/terapia , Distribución Aleatoria , Ratas , Ratas Sprague-Dawley , Factores de Tiempo
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