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Due to a lack of technologies that harvest green and sustainable energy, unutilized compressed air energy during the operation of pneumatic systems is wasted. Liquid-solid triboelectric nano-generators (L-S TENGs) have been widely used as an advanced technology with broad development prospects due to their advantages of a simple structure and long service life. Among them, liquid-solid triboelectric nanogenerators with tube structures have great potential for coupling multiple physical effects and integrating them into a single device. Herein, a U-shaped tube triboelectric nanogenerator composed of fluorinated ethylene propylene (FEP) and copper foil (UFC-TENG) is proposed to directly harvest unutilized compressed air energy. The UFC-TENG can collect unutilized compressed air energy with a stable peak voltage and current of approximately 33 V and 0.25 µA, respectively. When the alternating frequency of the liquid is 0.9 Hz, the unutilized compressed air can drive the UFC-TENG unit with an inner diameter of 12 mm, achieving a maximum output power of 3.93 µW at an external load resistance of 90 MΩ. The UFC-TENG is a novel driving method for L-S TENGs and demonstrates the promising potential of TENGs in the harvesting of unutilized compressed air energy in pneumatic systems.
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Due to its simple structure and lack of moving parts, the supersonic air ejector has been widely applied in the fields of machinery, aerospace, and energy-saving. The performance of the ejector is influenced by the flow channel structure and the velocity of the jet, thus the confined jet is an important limiting factor for the performance of the supersonic air ejector. In order to investigate the effect of the confined jet on the performance of the ejector, an air ejector with a rectangular section was designed. The effects of the section width (Wc) on the entrainment ratio, velocity distribution, turbulent kinetic energy distribution, Mach number distribution, and vorticity distribution of the rectangular section air ejector were studied numerically. The numerical results indicated that the entrainment ratio of the rectangular section air ejector increased from 0.34 to 0.65 and the increment of the ER was 91.2% when the section width increased from 1 mm to 10 mm. As Wc increased, the region of the turbulent kinetic energy gradually expanded. The energy exchange between the primary fluid and the secondary fluid was mainly in the form of turbulent diffusion in the mixing chamber. In addition to Wc limiting the fluid flow in the rectangular section air ejector, the structure size of the rectangular section air ejector in the XOY plane also had a limiting effect on the internal fluid flow. In the rectangular section air ejector, the streamwise vortices played an important role in the mixing process. The increase of Wc would increase the distribution of the streamwise vortices in the constant-area section. Meanwhile, the distribution of the spanwise vortices would gradually decrease.
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OBJECTIVE: Distal clavicle fracture classification directly affects the treatment decisions. It is unclear whether the classification systems implemented differ depending on surgeons' backgrounds. This study aimed to compare the interobserver agreement of four classification systems used for lateral clavicle fractures by shoulder specialists and general trauma surgeons. METHODS: Radiographs of 20 lateral clavicle fractures representing a full spectrum of adult fracture patterns were analyzed by eight experienced shoulder specialists and eight general trauma surgeons from 10 different hospitals. All cases were graded according to the Orthopedic Trauma Association (OTA), Neer, Jäger/Breitner, and Gongji classification systems. To measure observer agreement, Fleiss' kappa coefficient (κ) was applied and assessed. RESULTS: When only X-ray films were presented, both groups achieved fair agreement. However, when the 3D-CT scan images were provided, improved interobserver agreement was found in the specialist group when the OTA, Jäger/Breitner, and Gongji classification systems were used. In the generalist groups, improved agreement was found when using the Gongji classification system. In terms of interobserver reliability, the OTA, Neer, and Jäger/Breitner classification systems showed better agreement among shoulder specialists, while a slightly lower level of agreement was found using the Gongji classification system. For the OTA classification system, interobserver agreement had a mean kappa value of 0.418, ranging from 0.446 (specialist group) to 0.402 (generalist group). For the Neer classification system, interobserver agreement had a mean kappa value of 0.368, ranging from 0.402 (specialist group) to 0.390 (generalist group). For the Jäger/Breitner classification system, the inter-observer agreement had a mean kappa value of 0.380, ranging from 0.413 (specialist group) to 0.404 (generalist group). For the Gongji classification system, interobserver agreement had a mean kappa value of 0.455, ranging from 0.480 (specialist group) to 0.485 (generalist group). CONCLUSION: Generally speaking, 3D-CT scans provide a richer experience that can lead to better results in most classification systems of lateral clavicle fractures, highlighting the value of digitization and specialization in diagnosis and treatment. Competitive interobserver agreement was exhibited in the generalist group using the Gongji classification system, suggesting that the Gongji classification is suitable for general trauma surgeons who are not highly experienced in the shoulder field.
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Fraturas Ósseas , Cirurgiões , Adulto , Humanos , Clavícula/lesões , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Fraturas Ósseas/cirurgiaRESUMO
OBJECTIVE: Anterolateral coronal fractures are so rare that the mechanism of injury, the type of combined fracture and ligament injury, and the optimal treatment are unknown. To study the outcome of surgical treatments for anterolateral (AL) fracture of the ulna coronoid process (Adams Type IV) and summarize the characteristics of this type of fracture and to guide clinical applications. METHODS: From February 2015 to April 2021, 32 patients were included in the study. All patients had standard radiography with anteroposterior and lateral views, computed tomography, and intraoperative fluoroscopy. All patients were treated surgically. Surgery-related information, including surgical approach, operation duration, blood loss, and repairing the lateral collateral ligament and the medial collateral ligament integrity, were recorded. The patient's clinical details, such as the final range of motion (ROM), the Broberg-Morrey scores and the visual analogue scale (VAS) at the last follow-up, were described. The chi-square test or Fisher's exact test was used for statistical analysis. RESULTS: We divided patients into two groups according to the anterolateral coronoid fracture morphology. In the intact group, 20 patients with an intact anterolateral coronoid fracture fragment. In the comminuted group, 12 patients with comminuted anterolateral coronoid fracture fragments extended the less sigmoid notch of the ulna. There was no difference in age, sex, total incision length, follow-up duration, and recovery with rehabilitation among the two groups (all Ps >0.05). The other follow-up outcomes, such as elbow ROM (Flexion, Extension, Posterior rotation, Anterior rotation), VAS score, or Broberg-Morrey scores, were not different between the two groups (all Ps >0.05). Both groups achieved relatively satisfactory clinical outcomes, and the Broberg-Morrey score and index excellence rate reached 84.38%. There is a statistical difference in the history of elbow dislocation (P = 0.017), radial head fracture type (P = 0.041), operation duration (P = 0.014) and blood loss at operation (P = 0.029) between the two groups. Cannulated screws, anchors, and sutures were used as point fixation in the coronoid process of the ulna. There was a statistical difference between the two groups in the choice of internal fixation (P = 0.020). CONCLUSIONS: For anterolateral ulnar coronoid fractures with different degrees of comminution, effective and reliable surgical treatment can achieve better results and fewer complications.
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Articulação do Cotovelo , Fraturas Cominutivas , Fraturas do Rádio , Fraturas da Ulna , Humanos , Resultado do Tratamento , Ulna/cirurgia , Fraturas da Ulna/diagnóstico por imagem , Fraturas da Ulna/cirurgia , Articulação do Cotovelo/cirurgia , Fixação Interna de Fraturas/métodos , Fraturas do Rádio/cirurgia , Fraturas Cominutivas/diagnóstico por imagem , Fraturas Cominutivas/cirurgia , Amplitude de Movimento Articular , Estudos RetrospectivosRESUMO
OBJECTIVE: Current X-ray-based classification methods cannot describe all distal clavicle fracture (DCF) patterns, especially the osteoligamentous injury pattern of DCFs. We aimed to develop a novel classification based on the osteoligamentous injury pattern of the DCFs and investigated its reliability. METHODS: All DCFs from January 2017 to January 2022 were respectively screened and 45 cases (mean age 20-78; male 31, female 14) met the including criteria and were enrolled. Based on their Zanca view X-ray radiograph and three-dimensional CT construction images, we analyzed the osteoligamentous injury pattern of each case, particularly the acromioclavicular (AC) and coracoclavicular ligaments and their bone attachment. Then we developed a novel classification method, five types in total, sorting all DCFs according to their lesion manifestations of osteoligamentous complex. Also, we investigated the inter- and intra-observer reliability using kappa value. RESULTS: A novel classification method for DCF was developed, manifesting the avulsion or rupture of conoid and trapezoid ligaments, and involvement of AC joint. Forty-five cases of DCFs were included in this study. Among them, 11 (24.4%) were Type 1 fracture, three (6.7%) cases were Type 2, six cases (13.3%) were Type 3, 21 (46.7%) were Type 4, four (8.9%) were Type 5. Kappa values for inter-observer agreement were 0.57 after first evaluation and 0.61 after second evaluation. Intra-observer agreement was 0.72 for experienced shoulder specialist and 0.63 for radiologist. CONCLUSION: This new classification method is reliable to use, supplementary to current classification systems, and emphasizes on the osteoligamentous complex injury when opting for the treatment.
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Fraturas Ósseas , Procedimentos Ortopédicos , Humanos , Masculino , Feminino , Adulto Jovem , Adulto , Pessoa de Meia-Idade , Idoso , Clavícula/lesões , Reprodutibilidade dos Testes , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Radiografia , Ligamentos Articulares/diagnóstico por imagem , Ligamentos Articulares/cirurgiaRESUMO
OBJECTIVE: Calcar comminution has been considered to be the main cause of the failure of internal fixation and fracture nonunion in proximal humerus surgery. Anatomical reduction and increasing the strength of internal fixation is the key to success. The purpose of this study was to investigate the short-term clinical effect of dual plate fixation in the treatment of proximal humeral fractures with calcar comminution. METHODS: The data of 37 patients with proximal humeral fractures with calcar comminution, treated in our departments from July 2018 to April 2020, were retrospectively analyzed. These patients were treated with anterior plate and lateral PHILOS plate, and followed up for more than 12 months, including 25 cases in Tianjin Hospital and 12 cases in Shanghai General Hospital. The patients included 12 males and 25 females, their age was 54.89 ± 13.59 years (range from 32-79 years), and 21 patients had dominant hand injury. According to the Neer classification, there were 11 two-part fractures, 22 three-part fractures, and four four-part fractures. The range of motion of the shoulder joint, visual analog scale (VAS), American Shoulder and Elbow Surgeons Shoulder Score (ASES), Constant-Murley shoulder score, neck-shaft angle, anterior-posterior angle, and other complication scores were recorded at the last follow-up. RESULTS: All 37 patients were followed up after operation, and the follow-up time was 21.81 ± 7.35 months (range from 12-36 months). The fractures of all 37 patients had healed at the last follow-up visit. The neck-shaft angle measured immediately after operation was 132.59° ± 8.34°, and the neck-shaft angle measured at the last follow-up visit was 132.38 ± 8.53°. The anterior-posterior angle measured immediately after surgery was 3.45° ± 0.81°, and the anterior-posterior angle at the last follow-up visit was 3.66° ± 0.77°. The range of motion of the shoulder joint was as follows: the shoulder joint could be forward elevated by 158.11° ± 13.09° (range: 140°-180°), rotated externally by 38.38° ± 7.55° (range: 20°-45°), and internally rotated to T4-L4 level. The VAS score was 0.46 ± 0.87 (range: 0-3), the ASES was 86.58 ± 8.79 (range: 56.7-100), and the Constant-Murley score was 88.76 ± 8.25 (range: 60-100). Thirty-three cases were excellent, and four cases were good. No obvious complications occurred. CONCLUSION: The combination of anterior plate and lateral PHILOS plate in the treatment of proximal humeral fractures with calcar comminution can achieve stable fixation, and the postoperative clinical and imaging outcome was satisfactory. Firstly, the anterior plate can provide temporary stability when the Kirschner wires are removed, which can provide space for lateral plate placement during fracture reduction and fixation. Secondly, additional support by the anterior plate can provide higher stability in complex fractures with calcar comminution.
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Fraturas Cominutivas , Fraturas do Úmero , Fraturas do Ombro , Masculino , Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Idoso , Ombro , Estudos Retrospectivos , China , Fixação Interna de Fraturas/métodos , Fraturas do Ombro/cirurgia , Fraturas do Ombro/etiologia , Placas Ósseas , Úmero/cirurgia , Fraturas do Úmero/etiologia , Resultado do TratamentoRESUMO
We explored the mechanism of human osteosarcoma MG-63 cell apoptosis induced by asta-xanthin. The MTT assay was used to detect the effect of astaxanthin on cell viability. Morphological changes associated with apoptosis were observed after DAPI staining. Early and late stages of apoptosis were detected by flow cytometry with annexin V-FITC/PI staining. Activation of caspases-8, -9 and -3 was detected by enzyme activity in vitro. Changes in the mitochondrial membrane potential were detected by MitoCapture staining. Western blot was used to detect the cleavage of PARP, which is a caspase-3 substrate, the release of cytochrome c and Smac into the cytosol, the translocation of pro-apoptotic proteins Bax and Bak, and the expression of mitochondrial pathway-related proteins. The translocation of Bax was also detected by immunofluorescence assay. Astaxanthin significantly inhibited the viability of human osteosarcoma MG-63 cells with an IC50 value of 12.36 µg/ml. The DAPI-stained cells showed characteristic apoptotic morphological changes - cell shrinkage, cell membrane blebbing, nuclear condensation, and apoptotic body formation. Cytochrome c and Smac were released from mitochondria to the cytosol. Pro-apoptotic proteins Bax and Bak were rapidly translocated to mitochondria after six hours of astaxanthin action. Caspases-9 and -3 were activated and PARP was cleaved. The expression of anti-apoptotic proteins Bcl-2, Bcl-xL and XIAP was significantly decreased. Astaxanthin induced human osteosarcoma MG-63 cell apoptosis through the mitochondria-mediated endogenous apoptosis pathway.
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Citocromos c , Osteossarcoma , Humanos , Proteína X Associada a bcl-2/metabolismo , Citocromos c/metabolismo , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/uso terapêutico , Apoptose , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Proteínas Reguladoras de Apoptose/farmacologia , Proteínas Reguladoras de Apoptose/uso terapêutico , Osteossarcoma/tratamento farmacológico , Osteossarcoma/metabolismo , XantofilasRESUMO
Background: The enhanced recovery after surgery (ERAS) program is aimed to shorten patients' recovery process and improve clinical outcomes. This study aimed to compare the outcomes between the ERAS program and the traditional pathway among patients with ankle fracture and distal radius fracture. Methods: This is a multicenter prospective clinical controlled study consisting of 323 consecutive adults with ankle fracture from 12 centers and 323 consecutive adults with distal radial fracture from 13 centers scheduled for open reduction and internal fixation between January 2017 and December 2018. According to the perioperative protocol, patients were divided into two groups: the ERAS group and the traditional group. The primary outcome was the patients' satisfaction of the whole treatment on discharge and at 6 months postoperatively. The secondary outcomes include delapsed time between admission and surgery, length of hospital stay, postoperative complications, functional score, and the MOS item short form health survey-36. Results: Data describing 772 patients with ankle fracture and 658 patients with distal radius fracture were collected, of which 323 patients with ankle fracture and 323 patients with distal radial fracture were included for analysis. The patients in the ERAS group showed higher satisfaction levels on discharge and at 6 months postoperatively than in the traditional group (P < 0.001). In the subgroup analysis, patients with distal radial fracture in the ERAS group were more satisfied with the treatment (P=0.001). Furthermore, patients with ankle fracture had less time in bed (P < 0.001) and shorter hospital stay (P < 0.001) and patients with distal radial fracture received surgery quickly after being admitted into the ward in the ERAS group than in the traditional group (P=0.001). Conclusions: Perioperative protocol based on the ERAS program was associated with high satisfaction levels, less time in bed, and short hospital stay without increased complication rate and decreased functional outcomes.
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Fraturas do Tornozelo , Recuperação Pós-Cirúrgica Melhorada , Fraturas do Rádio , Adulto , Fraturas do Tornozelo/cirurgia , Humanos , Tempo de Internação , Estudos Prospectivos , Fraturas do Rádio/cirurgia , Resultado do TratamentoRESUMO
The emergence of SARS-CoV-2 variants and potentially other highly pathogenic sarbecoviruses in the future highlights the need for pan-sarbecovirus vaccines. Here, we discovered a new STING agonist, CF501, and found that CF501-adjuvanted RBD-Fc vaccine (CF501/RBD-Fc) elicited significantly stronger neutralizing antibody (nAb) and T cell responses than Alum- and cGAMP-adjuvanted RBD-Fc in mice. Vaccination of rabbits and rhesus macaques (nonhuman primates, NHPs) with CF501/RBD-Fc elicited exceptionally potent nAb responses against SARS-CoV-2 and its nine variants and 41 S-mutants, SARS-CoV and bat SARSr-CoVs. CF501/RBD-Fc-immunized hACE2-transgenic mice were almost completely protected against SARS-CoV-2 challenge, even 6 months after the initial immunization. NHPs immunized with a single dose of CF501/RBD-Fc produced high titers of nAbs. The immunized macaques also exhibited durable humoral and cellular immune responses and showed remarkably reduced viral load in the upper and lower airways upon SARS-CoV-2 challenge even at 108 days post the final immunization. Thus, CF501/RBD-Fc can be further developed as a novel pan-sarbecovirus vaccine to combat current and future outbreaks of sarbecovirus diseases.
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COVID-19 , Vacinas , Animais , Anticorpos Neutralizantes , Anticorpos Antivirais , COVID-19/prevenção & controle , Vacinas contra COVID-19 , Macaca mulatta , Camundongos , Coelhos , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Linfócitos TRESUMO
In this paper, sulfated ZrO2 were synthesized via precipitation and impregnation method, and the promoting effects of support sulfation on selective catalytic reduction (SCR) performance of CeO2/ZrO2 catalysts were investigated. The results revealed that sulfated ZrO2 could significantly enhance the SCR activity of CeO2/ZrO2 catalysts in a wide temperature range. Especially when S/Zr molar ratio was 0.1, CeO2/ZrO2-0.1S catalyst exhibited a large operating temperature window of 251 â¼ 500 °C and its N2 selectivity was 100 % in the temperature range of 150 â¼ 500 °C. Moreover, CeO2/ZrO2-0.1S catalyst possessed a superior low-temperature activity over 0.1S-CeO2/ZrO2 catalyst. After exposing to 100 ppm SO2 for 15 h, a high NO conversion efficiency of CeO2/ZrO2-0.1S catalyst (90.7 %) could still be reached. The characterization results indicated that ZrO2 treated with a proper dosage of sulfate acid was beneficial to enlarge the specific surface area greatly. Sulfated ZrO2 was also in favor of promoting the transformation of CeO2 from crystalline state to highly-dispersed amorphous state, and inhibiting the transformation of ZrO2 from tetragonal to monoclinic phase. It could also enhance the total surface acidity greatly with an increase in both Brønsted acid sites and Lewis acid sites, thus significantly improving NH3 adsorption on catalyst surface. Besides, the promoting effect of support sulfation on SCR performance of CeO2/ZrO2 catalysts was also related with the enhanced redox property, higher Ce3+/(Ce3++Ce4+) ratio and abundant surface chemisorbed labile oxygen. The in-situ DRIFTS results implied that nitrate species coordinated on the surface of CeO2/ZrO2-0.1S catalyst could participate in the Selective catalytic reduction with ammonia (NH3-SCR) reactions at either medium or high temperature, suggesting that both Eley-Rideal (E-R) and Langmuir-Hinshelwood (L-H) mechanisms might be followed in SCR reactions.
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Cério , Sulfatos , Amônia , Catálise , OxirreduçãoRESUMO
To better understand the evaporation of a non-spherical droplet, a two-dimensional simulation was conducted to investigate the evaporation on the asymmetric cross-section of non-spherical sessile droplets, which are characterized by two curvatures with two different contact angles on both sides. The temperature distribution, internal flow, and evaporation flux distribution at a quasi-steady state were revealed to be different from the spherical droplets. When heated from the substrate, the lowest surface temperature moves to the side of higher curvature or larger contact angle, forming a single vortex in the droplet. This single-vortex formation continues to be enhanced by enlarging the contact angle discrepancy. Unlike spherical droplets, the smaller curvature side of a non-spherical sessile droplet will release more evaporation flux. In addition, it is found that the non-spherical sessile droplets could surpass the spherical sessile droplets in evaporation flux.
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OBJECTIVE: To assess the short-term efficacy of reverse shoulder arthroplasty in the treatment of complex proximal humeral fractures in the elderly. METHODS: Forty-three elderly patients treated operatively for complex proximal humeral fractures with reverse shoulder arthroplasty from July 2017 to January 2019 were retrospectively reviewed. To be specific, 12 males and 31 females were reviewed with an average age of 72.0 years (range, 66-78 years). All fractures were attributed to trauma and treated for 8.0 days on average (range, 6-11 days). As suggested from Neer classification, 21 cases (48.8%, 21/43) were three-part fractures, and 22 (51.2%, 22/43) were four-part fractures. To assess the postoperative efficacy, Visual Analog Scale (VAS), American Society of Shoulder and Elbow Surgery Shoulder Joint Score (ASES), Constant-Murley score and radiological examination were adopted. The Neer three-part fracture group and the Neer four-part fracture group were compared. RESULTS: There was no significant difference in age, gender, operation time, and follow-up period between Neer three-part fracture group and Neer four-part fracture group. All operations were successfully performed, and the average operation time was 120-170 min, with an average of 141.3 min. Besides, the mean blood loss was 407.0 mL (250-700 mL), and the average intraoperative blood transfusion reached 446.5 mL (400-800 mL). All patients received the follow-up for 6 to 16 months, that is for 10.9 months on average. All patients were discharged in 7 days after operation, and no wound-related complications were identified. In 8 weeks, the greater and lesser tuberosities of all patients healed completely. During the last follow-up, no loosening or dislocation of prosthesis was detected, and the forward elevation of 133.0 (100°- 165°), the external rotation of 29.5° (20°-35°), the internal rotation of 46.7°(30°-60°), the VAS score of 0.8(0-3), the ASES score of 89.1(78.8-100.0) were achieved. Constant-Murley score reached 88.7 (range, 70-98). There was no significant difference between Neer three-part fracture group and Neer four-part fracture group (P > 0.05). A 71-year-old patient developed the symptoms of axillary nerve injury after operation; he recovered completely at 6 weeks after the operation, which had not adversely affected the functional rehabilitation exercise or the stability of the prosthesis. At the follow-up, no other complications (e.g., infection, acromial stress fracture, and scapular notching) were identified in all patients. CONCLUSION: The short-term efficacy of one-stage reverse shoulder arthroplasty to treat complex proximal humeral fractures in the elderly is satisfactory.
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Artroplastia do Ombro/métodos , Fraturas do Ombro/cirurgia , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Medição da Dor , Amplitude de Movimento Articular , Estudos Retrospectivos , Inquéritos e QuestionáriosRESUMO
OBJECTIVE: To figure out the difference between patients with posterior Monteggia fractures which were concomitant with proximal radioulnar joint (PRUJ) dislocation and posterior fracture-dislocation of the proximal ulna that were not concomitant with PRUJ. METHODS: From January 2016 to January 2019, 37 consecutive adult patients who had posterior fracture-dislocation of proximal ulna (no PRUJ dislocation, n = 16) and posterior Monteggia fractures (PRUJ dislocation, n = 21) were included. All patients had intraoperative fluoroscopy, computed tomography (CT) scans, and standard radiography (anteroposterior view and lateral view). The mechanism of injury, the cases with open fracture, sustained multiple injuries and classification of fracture was recorded. The clinical details of the patients such as the final range of motion (ROM) and the Broberg-Morrey scores were described. RESULTS: Patients with PRUJ dislocation (ten type A, five type B, and six type D) and those without concomitant PRUJ dislocation (fifteen type A and one type C) exhibited an obvious difference according to the classifications of Jupiter et al. (P = 0.010). Ninety-five percent of patients who had PRUJ dislocation were accompanied by a metaphyseal fracture, while only 50% of the patients who did not have PRUJ dislocation were accompanied by a metaphyseal fracture (P = 0.002). Meanwhile, 16 of 20 metaphyseal fractures had more than one fragment in the group of dislocations, but five of eight metaphyseal fractures were comminuted in the control group. The two groups exhibited an obvious difference (P = 0.009). The 21 patients who sustained a radioulnar dislocation had less mean arc of flexion, pronation, and Broberg-Morrey scores were significantly less than the patients of the control group (flexion: 117.38 ± 14.46 vs 127.50 ± 13.416, P = 0.035; pronation: 59.76 ± 11.88 vs 67.50 ± 6.58, P = 0.017; Broberg-Morrey: 80.48 ± 12.17 vs 88.19 ± 10.28, P = 0.040). CONCLUSIONS: Patients suffering posterior Monteggia fractures had more metaphyseal fractures, more comminuted fractures of the metaphysis, and worse ultimate ulnohumeral motion than patients of posterior fracture-dislocation of proximal ulna.
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Fratura-Luxação/classificação , Fratura-Luxação/diagnóstico por imagem , Fratura de Monteggia/classificação , Fratura de Monteggia/diagnóstico por imagem , Adulto , Idoso , Feminino , Fratura-Luxação/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Fratura de Monteggia/cirurgia , Amplitude de Movimento Articular , Estudos Retrospectivos , Inquéritos e Questionários , Adulto JovemRESUMO
Fe-Mn/TiO2 catalysts were prepared through the wet impregnation process to selective catalytic reduction of NO by NH3 at low temperature, and series of experiments were conducted to investigate the effects of key precursors on their SCR performance. Ferric nitrate, ferrous sulfate, and ferrous chloride were chosen as Fe precursors while manganese nitrate, manganese acetate, and manganese chloride as Mn precursors. These precursors had been commonly used to prepare Fe-Mn/TiO2 catalysts by numerous researchers. The results showed that there were distinct differences in NO conversion efficiencies at low temperature of catalysts prepared with different precursors. Catalysts prepared with ferric nitrate and manganese nitrate precursors exhibited the best catalytic performance at low temperature, while three kinds of catalysts prepared with manganese chloride precursors exhibited significantly low catalytic activity. All catalysts were characterized by XRD, SEM, H2-TPR, NH3-TPD, and XPS. The results indicated that when the catalysts were prepared with manganese nitrate or manganese acetate as precursors, Mn4+ contents and Oß/(Oß + Oα) ratios decreased in an order of ferric nitrate > ferrous sulfate > ferrous chloride, which was consistent with the change of catalytic activities of the corresponding catalysts at low temperature. It can be found that the excellent catalytic performance of Fe(A)-Mn(a)/TiO2 was ascribed to high redox property and enrichment of Mn4+species and surface chemical labile oxygen groups.
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Amônia , Manganês , Catálise , Oxirredução , Temperatura , TitânioRESUMO
BACKGROUND: Proximal humeral fractures represent the third most common fragility fracture treated in osteoporotic populations, after hip and distal radial fractures. The purpose of this study was to characterize the spatial variability in cortical geometry in the proximal humerus in postmenopausal women. METHODS: The proximal humeri in 43 healthy postmenopausal women were imaged by computed tomography. Cortical bone mapping was applied to create color 3-dimensional thickness maps for each proximal humerus. Cortical parameters, including the cortical thickness (CTh), cortical mass surface density (CM), and endocortical trabecular density, were measured over the humeral head and metaphyseal region after 15 regions of interest (ROIs) were defined. RESULTS: In the humeral head region, significant differences in CTh and CM values were detected between the anterior, lateral, and posterior walls (P < .05). The highest CTh and CM were found in the anterior wall in each plane (P < .05). Regarding the endocortical trabecular density, no significant findings were noted in the 3 planes (P > .05). In the metaphyseal region, the cortical structure in the medial column had higher CTh and CM values in ROI 10 compared with the lateral column (P < .05). The highest CTh and CM values of compact bone were seen in ROI 10 of the medial column (ROIs 10-12) (P < .05). CONCLUSION: Our results showed significant regional variation of cortical bone in the humeral head region in postmenopausal women. Similar conditions were seen in the medial column in the metaphyseal region. This finding provides discriminatory information for stronger fixation of implants.
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Densidade Óssea , Osso Cortical/diagnóstico por imagem , Cabeça do Úmero/diagnóstico por imagem , Pós-Menopausa/fisiologia , Idoso , Idoso de 80 Anos ou mais , Osso Cortical/patologia , Epífises/diagnóstico por imagem , Feminino , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada por Raios XRESUMO
BACKGROUND: Incidence of proximal humeral fractures dramatically increased over the last decade due to demographic changes. The goal of this study was to analyze regional characteristics of cortical bone in the humeral head region using cortical bone mapping (CBM) technique. METHODS: The proximal humerus of 103 healthy volunteers was imaged by clinical computed tomography (CT) scans. Three groups of volunteers were identified according to age: group A (20-39years), group B (40-59years), and group C (>60years). CBM was applied to create color 3D thickness maps for each proximal humerus. Cortical parameters, including the cortical thickness (CTh), cortical mass surface density (CM), and the endocortical trabecular density (ECTD) were measured over humeral head region after nine regions of interest (ROI) were defined. RESULTS: Cortical bone structure of the humeral head region varied dramatically in cross-section independent of age, with significant cortical thinning at the posterior wall. Particularly, notable cortical thinning was also found in the distal end of lateral wall at 60years of age or older. The degree of regional variability of cortical properties within lateral wall tended to diminish with age. CONCLUSION: Substantial regional variations in cortical bone structure at humeral head region were observed quantitatively in this study. These morphologic data provided useful information on clinical medicine such as surgical fixation.
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Osso Cortical/metabolismo , Osso Cortical/patologia , Cabeça do Úmero/metabolismo , Cabeça do Úmero/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Adulto JovemRESUMO
A miniature steam ejector refrigeration system embedded with a capillary pump loop can result in a compact design which can be used for electronics cooling. In this paper, computational fluid dynamics (CFD) is employed to investigate the effects of the area ratio of the ejector constant-area mixing section to the nozzle throat, the length of the constant-area section, and the nozzle exit position (NXP), on the performance of a miniature steam ejector. Results show that the performance of the miniature steam ejector is very sensitive to the area ratio of the constant-area mixing section to the nozzle. For the needs of practical application, the area ratio of the constant-area mixing section to the nozzle should be smaller than 16 when the temperature of the primary flow is 60 °C. The NXP plays an important role in the flow phenomena inside the miniature ejector. The critical back pressure is more sensitive to length of the constant-area mixing section than the entrainment ratio. Results of this investigation provided a good solution to the miniature steam ejector embedded with a capillary pump loop for electronics cooling application.
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Methionine restriction (MR) is proven to increase the lifespan; and it also affects the bone density and the innate immune system. The aim of this study is to explore the effect of methionine restriction on bone density and natural killer (NK) cells. C57BL/6J mice were subjected to either basal diet (BD, containing 0.80% methionine) or methionine-restricted diet (containing 0.14% methionine). Mice with MR diet displayed reduced bone mass and decrease in the cytotoxicity of NK from the spleen, compared to BD animals. Also, mice with MR diet had an inferior body weight (P < 0.05) and higher plasma levels of adiponectin and FGF21 (P < 0.05) but lower concentrations of leptin and IGF-1 (P < 0.05). Overall, the investigation shows that methionine affects bone density and NK cell cytotoxicity.
Assuntos
Adiponectina/sangue , Densidade Óssea , Fatores de Crescimento de Fibroblastos/sangue , Células Matadoras Naturais/metabolismo , Leptina/sangue , Metionina/deficiência , Animais , Células Matadoras Naturais/patologia , Masculino , Camundongos , Baço/metabolismo , Baço/patologiaRESUMO
Focal adhesions are protein complexes that link metazoan cells to the extracellular matrix through the integrin family of transmembrane proteins. Integrins recruit many proteins to these complexes, referred to as the "adhesome." We used proximity-dependent biotinylation (BioID) in U2OS osteosarcoma cells to label proteins within 15 to 25 nm of paxillin, a cytoplasmic focal adhesion protein, and kindlin-2, which directly binds ß integrins. Using mass spectrometry analysis of the biotinylated proteins, we identified 27 known adhesome proteins and 8 previously unknown components close to paxillin. However, only seven of these proteins interacted directly with paxillin, one of which was the adaptor protein Kank2. The proteins in proximity to ß integrin included 15 of the adhesion proteins identified in the paxillin BioID data set. BioID also correctly established kindlin-2 as a cell-cell junction protein. By focusing on this smaller data set, new partners for kindlin-2 were found, namely, the endocytosis-promoting proteins liprin ß1 and EFR3A, but, contrary to previous reports, not the filamin-binding protein migfilin. A model adhesome based on both data sets suggests that focal adhesions contain fewer components than previously suspected and that paxillin lies away from the plasma membrane. These data not only illustrate the power of using BioID and stable isotope-labeled mass spectrometry to define macromolecular complexes but also enable the correct identification of therapeutic targets within the adhesome.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Proteínas de Transporte , Moléculas de Adesão Celular , Proteínas do Citoesqueleto , Adesões Focais , Proteínas Supressoras de Tumor , Proteínas Adaptadoras de Transdução de Sinal/química , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas Reguladoras de Apoptose , Biotinilação , Células COS , Proteínas de Transporte/química , Proteínas de Transporte/metabolismo , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Linhagem Celular Tumoral , Chlorocebus aethiops , Proteínas do Citoesqueleto/química , Proteínas do Citoesqueleto/metabolismo , Adesões Focais/química , Adesões Focais/metabolismo , Humanos , Proteínas de Membrana/química , Proteínas de Membrana/metabolismo , Camundongos , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Proteínas Supressoras de Tumor/química , Proteínas Supressoras de Tumor/metabolismoRESUMO
Recent data strongly suggest the important role of miRNAs in various cancer-related processes. Osteosarcoma is the most common type of primary malignant bone tumor and is characterized by complex genetic changes and resistance to conventional treatments. In this study, the role of miRNA-15a (miR-15a) in the progression and metastasis of osteosarcoma was investigated. The result demonstrated that the expression of miR-15a was down-regulated in osteosarcoma tissues and cell lines as compared with that in adjacent non-neoplastic bone tissues and the osteoblastic cell line. In functional assays, miR-15a inhibited cell proliferation, migration and invasion in U2OS and MG-63 cells. Meanwhile, bioinformatic analysis combined with experimental confirmation demonstrated that tumor necrosis factor; α-induced protein 1 (TNFAIP1) gene is a potential target of miR-15a and can be directly regulated by miR-15a. Down-regulation of TNFAIP1 induced effects on osteosarcoma cell lines similar to those induced by miR-15a. Taken together, these data suggest that miR-15a may act as a tumor suppressor, which is commonly down-regulated in both osteosarcoma tissues and cells. TNFAIP1 plays an important role in mediating miR-15a dependent biological functions in osteosarcoma. Reintroduction of miR-15a may be a novel therapeutic strategy by down-regulating TNFAIP1 expression.