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1.
Nanomaterials (Basel) ; 13(17)2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37686967

RESUMO

This paper presents an original and sustainable method for producing ZnO nanoparticles (NPs) in response to global challenges (low energy requirements, low environmental impact, short production times, and high production yield). The method is based on an ion exchange process between an anionic resin and an aqueous ZnCl2 solution; it operates in one step at room temperature/ambient pressure without the need for complex apparatus or purification steps. From the kinetics, we observed the formation of pure simonkolleite, a zinc-layered hydroxide salt (Zn5(OH)8Cl2·H2O), after only 5 min of reaction. This compound, used elsewhere as a ZnO precursor after calcination at high temperatures, here decomposes at room temperature into ZnO, allowing extraordinary savings of time and energy. Finally, in only 90 min, pure and crystalline ZnO NPs are obtained, with a production yield > 99%. Several types of aggregates resulting from the self-assembly of small hexagonal platelets (solid or hollow in shape) were observed. Using our revolutionary method, we produced almost 10 kg of ZnO NPs per week without any toxic waste, significantly reducing energy consumption; this method allows transferring the use of these unique NPs from the laboratory environment to the real world.

2.
Orthop Rev (Pavia) ; 8(1): 6113, 2016 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-27114806

RESUMO

Total elbow arthroplasty (TEA) is utilized in the treatment of rheumatoid and post-traumatic elbow arthritis. TEA is a relatively low volume surgery in comparison to other types of arthroplasty and therefore little is known about current surgical utilization, patient demographics and complication rates in the United States. The purpose of our study is to evaluate the current practice trends and associated in-patient complications of TEA at academic centers in the United States. We queried the University Health Systems Consortium administrative database from 2007 to 2011 for patients who underwent an elective TEA. A descriptive analysis of demographics was performed which included patient age, sex, race, and insurance status. We also evaluated the following patient clinical benchmarks: hospital length of stay (LOS), hospital direct cost, in-hospital mortality, complications, and 30-day readmission rates. Our cohort consisted of 3146 adult patients (36.5% male and 63.5% female) with an average age of 58 years who underwent a total elbow arthroplasty (159 academic medical centers) in the United States. The racial demographics included 2334 (74%) Caucasian, 285 (9%) black, 236 (7.5%) Hispanic, 16 (0.5%) Asian, and 283 (9%) other patients. The mean LOS was 4.2±5 days and the mean total direct cost for the hospital was 16,300±4000 US Dollars per case. The overall inpatient complication rate was 3.1% and included mortality <1%, DVT (0.8%), re-operation (0.5%), and infection (0.4%). The 30-day readmission rate was 4.4%. TEA is a relatively uncommon surgery in comparison to other forms of arthroplasty but is associated with low in-patient and 30-day perioperative complication rate. Additionally, the 30-day readmission rate and overall hospital costs are comparable to the traditional total hip and knee arthroplasty surgeries.

3.
J Hand Surg Am ; 40(5): 934-9, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25772286

RESUMO

PURPOSE: We sought to independently validate the McQueen equation and LaFontaine's criteria as predictors of instability in a large series of distal radius fractures treated nonsurgically. In addition, we hypothesized that restoring the volar cortical integrity (ie, volar hook) would be another factor that would independently predict the maintenance of a closed reduction in a cast. METHODS: We screened 546 consecutive distal radius fractures with 168 meeting all inclusion criteria. Dorsal tilt, radial height, radial inclination, ulnar variance, and carpal malalignment were measured on initial postreduction and final radiographs. A univariate analysis evaluated the predictability of the McQueen equation, Lafontaine's criteria, and volar hook on each radiographic parameter. A multivariate analysis was performed using the significant results from the univariate analysis. RESULTS: In the univariate analysis, the McQueen formula, the number of Lafontaine criteria, and age all correlated with radial height, radial inclination, and ulnar variance. In the multivariate analysis, age correlated with the most radiographic factors including radial height, radial inclination, ulnar variance, and carpal alignment at healing. Volar hook correlated with dorsal tilt and carpal alignment at healing, and dorsal comminution correlated with dorsal tilt. CONCLUSIONS: In the nonsurgical treatment of distal radius fractures, we were able to validate the McQueen equation and Lafontaine's criteria in predicting the final radial height and inclination and final ulnar variance. Neither method was predictive of final dorsal tilt or carpal malalignment. However, restoring volar cortical continuity by hooking the volar cortex in the initial reduction proved to be the strongest predictor of final volar tilt, the change in volar tilt, and carpal malalignment at union. TYPE OF STUDY/LEVEL OF EVIDENCE: Therapeutic III.


Assuntos
Mau Alinhamento Ósseo/diagnóstico por imagem , Fixação de Fratura/métodos , Fraturas do Rádio/terapia , Adolescente , Adulto , Mau Alinhamento Ósseo/prevenção & controle , Moldes Cirúrgicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Resultado do Tratamento
4.
J Orthop Trauma ; 29(9): e326-30, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25635357

RESUMO

OBJECTIVE: To evaluate the ability of surgeons to determine whether the fibula is reduced in the sagittal plane in relation to the tibia based on the fluoroscopic images by comparison with the known normal for both the ipsilateral and contralateral ankles. METHODS: Perfect lateral radiographs of both ankles were obtained in 7 cadaveric specimens. The fibula was translated 2.5 and 5 mm in the anterior and posterior directions. Four orthopaedic trauma-trained surgeons were presented with a fictitious case consisting of a "normal" image, followed by 10 randomly selected images from both ankles, and were asked to determine whether the fibula was reduced, or displaced anteriorly or posteriorly. The ability of the surgeons to identify displacement and interobserver reliability was assessed. RESULTS: The surgeons were better able to identify malreduction than reduction (negative predictive value (NPV) 95% ipsilateral, 85% contralateral). The overall sensitivity for reduction was 94% for the ipsilateral ankle, but only 68% for the contralateral ankle. Anterior displacement and greater magnitudes of displacement were most easily diagnosed. All reviewers had the most difficulty with 2.5 mm of posterior displacement. The intraobserver agreement was excellent for anterior displacement and 5 mm of displacement in either direction (kappa = 0.71/0.75). Surgeons who routinely used the contralateral lateral radiograph were more accurate. CONCLUSIONS: Although it is unknown how much translational displacement of the syndesmosis is acceptable, it seems that the experienced surgeon will be able to reduce the joint within 2.5 mm and that fluoroscopic comparisons to the normal ankle are helpful in determining malreduction.


Assuntos
Traumatismos do Tornozelo/diagnóstico por imagem , Articulação do Tornozelo/diagnóstico por imagem , Fíbula/diagnóstico por imagem , Instabilidade Articular/diagnóstico por imagem , Posicionamento do Paciente/métodos , Tíbia/diagnóstico por imagem , Cadáver , Fluoroscopia , Humanos , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ossos do Tarso/diagnóstico por imagem
5.
Curr Biol ; 21(10): 835-40, 2011 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-21549599

RESUMO

The role of the transmembrane receptor Notch in the adult brain is poorly understood. Here, we provide evidence that bunched, a negative regulator of Notch, is involved in sleep homeostasis. Genetic evidence indicates that interfering with bunched activity in the mushroom bodies (MBs) abolishes sleep homeostasis. Combining bunched and Delta loss-of-function mutations rescues normal homeostasis, suggesting that Notch signaling may be involved in regulating sensitivity to sleep loss. Preventing the downregulation of Delta by overexpressing a wild-type transgene in MBs reduces sleep homeostasis and, importantly, prevents learning impairments induced by sleep deprivation. Similar resistance to sleep loss is observed with Notch(spl-1) gain-of-function mutants. Immunohistochemistry reveals that the Notch receptor is expressed in glia, whereas Delta is localized in neurons. Importantly, the expression in glia of the intracellular domain of Notch, a dominant activated form of the receptor, is sufficient to prevent learning deficits after sleep deprivation. Together, these results identify a novel neuron-glia signaling pathway dependent on Notch and regulated by bunched. These data highlight the emerging role of neuron-glia interactions in regulating both sleep and learning impairments associated with sleep loss.


Assuntos
Proteínas de Ligação a DNA/metabolismo , Proteínas de Drosophila/metabolismo , Drosophila/fisiologia , Homeostase/fisiologia , Receptores Notch/metabolismo , Transdução de Sinais/fisiologia , Sono/fisiologia , Adulto , Análise de Variância , Animais , Proteínas de Ligação a DNA/genética , Proteínas de Drosophila/genética , Humanos , Imuno-Histoquímica , Peptídeos e Proteínas de Sinalização Intracelular/genética , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Aprendizagem/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/metabolismo , Microscopia Confocal , Corpos Pedunculados/metabolismo , Mutação/genética , Neuroglia/metabolismo , Neurônios/metabolismo , Reação em Cadeia da Polimerase
6.
Orthop Nurs ; 29(6): 365-71; quiz 372-3, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21099641

RESUMO

Scheuermann's thoracic kyphosis is a condition characterized by increased posterior rounding of the thoracic spine in association with structural deformity of the vertebral elements. It is a structural deformity of the spine that is classically characterized by anterior wedging of 5° or more of 3 adjacent thoracic vertebral bodies with kyphosis measuring greater than 45° between T5 and T12. The cause of the deformity remains unknown but it is believed to be multifactorial, and it likely has a genetic component as well. Most adolescent patients seek orthopaedic evaluation for increased rounding and deformity of the thoracic spine that is occasionally associated with back pain. Parental concerns are also often related to the cosmetic deformity and the progressive nature of the condition. Bracing has been demonstrated to be an effective nonsurgical treatment modality for the skeletally immature child and/or adolescent with a progressive deformity. Operative management has been advocated for adolescents with progressive kyphosis measuring over 70°, for those who have had progression despite bracing, for patients with intractable back pain, and also for patients with unacceptable cosmetic deformity. Surgical options include posterior spinal arthrodesis with or without anterior spinal release via thoractomy or video-assisted thoracoscopic surgery (VATS). This article will review the diagnosis, pathophysiology, physical examination findings, and the nonoperative and surgical treatment options for adolescent patients with Scheuermann's kyphosis of the thoracic spine.


Assuntos
Doença de Scheuermann/fisiopatologia , Adolescente , Educação Continuada , Humanos , Exame Físico , Radiografia , Doença de Scheuermann/diagnóstico por imagem , Doença de Scheuermann/etiologia , Doença de Scheuermann/terapia
7.
Spine (Phila Pa 1976) ; 35(23): 2027-9, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20531072

RESUMO

STUDY DESIGN: A prospective, randomized trial comparing skin closure time between coaptive film and subcuticular Monocryl sutures in children undergoing posterior instrumented spinal fusion. OBJECTIVE: To prospectively compare skin closure time, complication rate and cosmetic result between coaptive film and subcuticular Monocryl wound closures in pediatric spine surgery. SUMMARY OF BACKGROUND DATA: Posterior instrumented spinal fusions for spinal deformity in children are time-consuming ventures that are demanding on both the patient and physician. Minimizing the time for skin closure at the end of prolonged surgery diminishes the physical burden on the surgeon, the operating room personnel, and reduces operating room costs. METHODS: Twenty-five children (mean age, 14.1 year) underwent posterior instrumented spinal fusion. Twenty-five incisions in 25 patients (12 closed with 3-0 subcuticular Monocryl sutures, 13 closed with coaptive film [Steri Strip S; 3 M company]) were evaluated. The method of skin closure was randomized before beginning the procedure and the surgeon informed just before skin closure. Closure time was recorded. A blinded plastic surgeon using a visual analogue scale assessed the cosmetic results at a minimum 3-month follow-up. RESULTS: Incisions closed with coaptive film required less time to complete than incisions closed with subcuticular suture. The mean time for skin closure using coaptive film was 290.62 seconds compared to the mean time of 674.75 seconds using Monocryl sutures (P < 0.000001). The average length of incisions closed with coaptive film was similar to the corresponding incisions that were closed with subcuticular Monocryl sutures (30.8 and 34.0 cm, respectively, P = 0.22). There was no significant difference in the cosmetic results or the number of wound complications using either technique. CONCLUSION: Coaptive film is a time-saving option for skin closure following pediatric spine surgery with comparable cosmetic results and no difference in complication rates.


Assuntos
Cifose/cirurgia , Escoliose/cirurgia , Fusão Vertebral/instrumentação , Suturas , Adesivos Teciduais , Técnicas de Fechamento de Ferimentos/instrumentação , Adolescente , Criança , Feminino , Humanos , Masculino , Estudos Prospectivos , Fusão Vertebral/métodos , Resultado do Tratamento , Cicatrização
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