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1.
Clin Orthop Relat Res ; 479(5): 1081-1093, 2021 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-33296152

RESUMO

BACKGROUND: Acetabular overcoverage is associated with pincer-type femoroacetabular impingement (FAI). A subtype of acetabular overcoverage is caused by a deep acetabulum with a negatively tilted acetabular roof, in which acetabular reorientation may be a preferable alternative to rim trimming to uncover the femoral head. We introduced the true reverse periacetabular osteotomy (PAO) in 2003, which in contrast to an anteverting PAO, also flexes and abducts the acetabulum relative to the intact ilium to decrease anterior and lateral femoral head coverage and correct negative tilt of the acetabular roof. To our knowledge, the clinical results of the true reverse PAO have not been evaluated. QUESTIONS/PURPOSES: For a group of patients who underwent reverse PAO, (1) Do patients undergoing reverse PAO demonstrate short-term improvement in pain, function, and hip ROM, and decreased acetabular coverage, as defined by lateral and anterior center-edge angle and Tönnis angle? (2) Are there identifiable factors associated with success or adverse outcomes of reverse PAO as defined by reoperation, conversion to THA, or poor patient-reported outcome scores? (3) Are there identifiable factors associated with early complications? METHODS: Between 2003 and 2017, two surgeons carried out 49 reverse PAOs in 37 patients. Twenty-five patients had unilateral reverse PAO and 12 patients had staged, bilateral reverse PAOs. To ensure that each hip was an independent data point for statistical analysis, we chose to include in our series only the first hip in the patients who had bilateral reverse PAOs. During the study period, our general indications for this operation were symptomatic lateral and anterior acetabular overcoverage causing FAI that had failed to respond to previous conservative or surgical treatment. Thirty-seven hips in 37 patients with a median (range) age of 18 years (12 to 41; interquartile range 16 to 21) were included in this retrospective study at a minimum follow-up of 2 years (median 6 years; range 2 to 17). Thirty-four patients completed questionnaires, 24 patients had radiographic evaluation, and 23 patients received hip ROM clinical examination. However, seven patients had not been seen in more than 5 years. The clinical and radiographic parameters of all 37 hips that underwent reverse PAO in 37 patients from a longitudinally maintained institutional database were retrospectively studied preoperatively and postoperatively. Adverse outcomes were considered conversion to THA or a WOMAC pain score greater than 10 at least 2 years postoperatively. Patient-reported outcomes, radiographic measurements, and hip ROM were evaluated preoperatively and at most recent follow-up using a paired t-test or McNemar test, as appropriate. Linear regression analysis was used to assess for identifiable factors associated with clinical outcomes. Logistic regression analysis was used to assess for identifiable factors associated with adverse outcomes and surgical complications. All tests were two-sided, and p values less than 0.05 were considered significant. RESULTS: At a minimum of 2 years after reverse PAO, patients experienced improvement in WOMAC pain (-7 [95% CI -9 to -5]; p < 0.001), stiffness (-2 [95% CI -3 to -1]; p < 0.001), and function scores (-18 [95% CI -24 to -12]; p < 0.001) and modified Harris Hip Score (mHHS) (20 [95% CI 13 to 27]; p < 0.001). The mean postoperative hip ROM improved in internal rotation (8° [95% CI 2° to 14°]; p = 0.007). Acetabular coverage, as defined by lateral center-edge angle (LCEA), anterior center-edge angle (ACEA), and Tönnis angle, improved by -8° (95% CI -12° to -5°; p < 0.001) for LCEA, -12° (95% CI -15° to -9°; p < 0.001) for ACEA, and 9° (95% CI 6° to 13°; p < 0.001) for Tönnis angle. The postoperative severity of radiographic arthritis was associated with worse WOMAC function scores such that for each postoperative Tönnis grade, WOMAC function score increased by 12 points (95% CI 2 to 22; p = 0.03). A greater postoperative Tönnis grade was also correlated with worse mHHS, with an average decrease of 12 points (95% CI -20 to -4; p = 0.008) in mHHS for each additional Tönnis grade. Presence of a positive postoperative anterior impingement test was associated with a decrease in mHHS score at follow-up, with an average 23-point decrease in mHHS (95% CI -34 to -12; p = 0.001). Nineteen percent (7 of 37) of hips had surgery-related complications. Four hips experienced adverse outcomes at final follow-up, with two patients undergoing subsequent THA and two with a WOMAC pain score greater than 10. We found no factors associated with complications or adverse outcomes. CONCLUSION: The early clinical and radiographic results of true reverse PAO compare favorably to other surgical treatments for pincer FAI, suggesting that reverse PAO is a promising treatment for cases of pincer FAI caused by global acetabular overcoverage. However, it is a technically complex procedure that requires substantial training and preparation by a surgeon who is already familiar with standard PAO, and it must be carefully presented to patients with discussion of the potential risks and benefits. Future studies are needed to further refine the indications and to determine the long-term outcomes of reverse PAO. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Acetábulo/cirurgia , Impacto Femoroacetabular/cirurgia , Cabeça do Fêmur/cirurgia , Articulação do Quadril/cirurgia , Osteotomia , Acetábulo/diagnóstico por imagem , Acetábulo/fisiopatologia , Adolescente , Adulto , Artroplastia de Quadril , Fenômenos Biomecânicos , Criança , Bases de Dados Factuais , Feminino , Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/fisiopatologia , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/fisiopatologia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/fisiopatologia , Humanos , Masculino , Osteotomia/efeitos adversos , Complicações Pós-Operatórias/etiologia , Complicações Pós-Operatórias/fisiopatologia , Complicações Pós-Operatórias/cirurgia , Amplitude de Movimento Articular , Recuperação de Função Fisiológica , Reoperação , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
2.
Biomed Res Int ; 2017: 2867653, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29333437

RESUMO

This paper deals with the engineering multicomponent nanofunctionalization process considering fundamental physicochemical features of nanostructures such as surface energy, chemical bonds, and electrostatic interactions. It is pursued by modeling the surface nanopatterning and evaluating the proposed technique and the models. To this end, the effects of surface modifications of nanoclay on surface interactions, orientations, and final features of TiO2/Mt nanocolloidal textiles functionalization have been investigated. Various properties of cross-linkable polysiloxanes (XPs) treated samples as well as untreated samples with XPs have been compared to one another. The complete series of samples have been examined in terms of bioactivity and some physical properties, given to provide indirect evidence on the surface nanopatterning. The results disclosed a key role of the selected factors on the final features of treated surfaces. The effects have been thoroughly explained and modeled according to the fundamental physicochemical features. The developed models and associated hypotheses interestingly demonstrated a full agreement with all measured properties and were appreciably confirmed by FESEM evidence (direct evidence). Accordingly, a guideline has been developed to facilitate engineering and optimizing the pre-, main, and post-multicomponent nanofunctionalization procedures in terms of fundamental features of nanostructures and substrates for biomedical applications and other approaches.


Assuntos
Materiais Biocompatíveis/química , Nanoestruturas/química , Titânio/química , Reagentes de Ligações Cruzadas/química , Siloxanas/química , Propriedades de Superfície , Têxteis
3.
Biomed Mater ; 12(4): 045014, 2017 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-28561741

RESUMO

An acid-free water-born chitosan derivative/montmorillonite has been successfully synthesized. A natural-based biopolymer, N-(2-hydroxy) propyl-3-trimethyl ammonium chitosan chloride, was synthesized, and its structure confirmed by Fourier transform infrared microscopy and conductometric titration. It was applied to the cationic ion-exchange reaction of montmorillonite. Then, the synthesized materials were used to produce water-born composite scaffolds for tissue engineering applications and formed an ultra-fine bead-free multicomponent nanofibrous scaffold. The scaffold was subjected to in vitro and in vivo investigations. The effects of both acidic and neutral reaction media on the efficiency of the cationic ion-exchange reaction of montmorillonite were investigated. A mechanism has been suggested for the more efficient cationic ion-exchange reaction achieved in the absence of the acid. In in vitro studies, the modified montmorillonite showed synergistic biocompatibility and cell growth with enhanced bioactivity compared to unmodified clay and even chitosan and the chitosan derivative. Scanning electron microscopy showed ultra-fine bead-free nanocomposite nanofibers. Improved biocompatibility, cell attachment, and cell growth were observed for the nanofibrous scaffolds compared to the individual components. In vivo experiments showed complete restoration of a critical-sized full-thickness wound without infection in 21 d. The technique provides a guideline to achieve chitosan nanofibrous morphology for multifunctional biomedical applications.


Assuntos
Bentonita/química , Quitosana/análogos & derivados , Nanocompostos/química , Nanofibras/química , Compostos de Amônio Quaternário/química , Alicerces Teciduais , Água/química , Ácidos/química , Animais , Materiais Biocompatíveis/química , Quitosana/química , Teste de Materiais , Microscopia Eletrônica de Varredura , Polímeros/química , Ratos , Espectroscopia de Infravermelho com Transformada de Fourier , Engenharia Tecidual , Difração de Raios X
4.
Pediatrics ; 137(1)2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26702029

RESUMO

CONTEXT: Kangaroo mother care (KMC) is an intervention aimed at improving outcomes among preterm and low birth weight newborns. OBJECTIVE: Conduct a systematic review and meta-analysis estimating the association between KMC and neonatal outcomes. DATA SOURCES: PubMed, Embase, Web of Science, Scopus, African Index Medicus (AIM), Latin American and Caribbean Health Sciences Information System (LILACS), Index Medicus for the Eastern Mediterranean Region (IMEMR), Index Medicus for the South-East Asian Region (IMSEAR), and Western Pacific Region Index Medicus (WPRIM). STUDY SELECTION: We included randomized trials and observational studies through April 2014 examining the relationship between KMC and neonatal outcomes among infants of any birth weight or gestational age. Studies with <10 participants, lack of a comparison group without KMC, and those not reporting a quantitative association were excluded. DATA EXTRACTION: Two reviewers extracted data on study design, risk of bias, KMC intervention, neonatal outcomes, relative risk (RR) or mean difference measures. RESULTS: 1035 studies were screened; 124 met inclusion criteria. Among LBW newborns, KMC compared to conventional care was associated with 36% lower mortality(RR 0.64; 95% [CI] 0.46, 0.89). KMC decreased risk of neonatal sepsis (RR 0.53, 95% CI 0.34, 0.83), hypothermia (RR 0.22; 95% CI 0.12, 0.41), hypoglycemia (RR 0.12; 95% CI 0.05, 0.32), and hospital readmission (RR 0.42; 95% CI 0.23, 0.76) and increased exclusive breastfeeding (RR 1.50; 95% CI 1.26, 1.78). Newborns receiving KMC had lower mean respiratory rate and pain measures, and higher oxygen saturation, temperature, and head circumference growth. LIMITATIONS: Lack of data on KMC limited the ability to assess dose-response. CONCLUSIONS: Interventions to scale up KMC implementation are warranted.


Assuntos
Método Canguru , Humanos , Recém-Nascido , Estudos Observacionais como Assunto , Ensaios Clínicos Controlados Aleatórios como Assunto
5.
J Neuropathol Exp Neurol ; 75(10): 981-997, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-27612489

RESUMO

Sudden infant death syndrome (SIDS) and sudden unexplained death in childhood (SUDC) are defined as sudden death in a child remaining unexplained despite autopsy and death scene investigation. They are distinguished from each other by age criteria, i.e. with SIDS under 1 year and SUDC over 1 year. Our separate studies of SIDS and SUDC provide evidence of shared hippocampal abnormalities, specifically focal dentate bilamination, a lesion classically associated with temporal lobe epilepsy, across the 2 groups. In this study, we characterized the clinicopathologic features in a retrospective case series of 32 children with sudden death and hippocampal formation (HF) maldevelopment. The greatest frequency of deaths was between 3 weeks and 3 years (81%, 26/32). Dentate anomalies were found across the pediatric age spectrum, supporting a common vulnerability that defies the 1-year age cutoff between SIDS and SUDC. Twelve cases (38%) had seizures, including 7 only with febrile seizures. Subicular anomalies were found in cases over 1 year of age and were associated with increased risk of febrile seizures. Sudden death associated with HF maldevelopment reflects a complex interaction of intrinsic and extrinsic factors that lead to death at different pediatric ages, and may be analogous to sudden unexplained death in epilepsy.

6.
Biomed Res Int ; 2013: 749240, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23998128

RESUMO

This paper deals with the synthesis of a biocompatible chitosan ammonium salt N-(2-hydroxy) propyl-3-trimethylammonium chitosan chloride (HTCC) and using it in montmorillonite ion-exchange process. HTCC-modified montmorillonite (Mt) with different chemical ratios was successfully synthesized, and their characteristics have been verified by XRD and FTIR analyses. Produced samples have been evaluated in terms of antibacterial efficiency and biocompatibility (cell culture test). Antibacterial efficiency of synthesized HTCC/Mt samples has been confirmed against both gram negative bacteria (Escherichia coli) and gram positive bacteria (Staphylococcus aureus). The results disclosed that the antibacterial efficiency of HTCC-modified montmorillonite was unexpectedly even more than HTCC. This excellent synergistic effect has been referred to entrapping bacteria between the intercalated structures of HTCC-modified montmorillonite. Then HTCC on clay layers can seriously attack and damage the entrapped bacteria. An extraordinary biocompatibility, cell attachment, and cell growth even more than tissue culture polystyrene (TCPS) have been recorded in the case of this novel kind of modified clay. Due to existing concerns about serious and chronic infections after implant placement, this natural-based bioactive and antibacterial modified clay can be used in electrospun nanofibers and other polymeric implants with promising mechanical properties for tissue engineering applications.


Assuntos
Fenômenos Fisiológicos Bacterianos/efeitos dos fármacos , Bentonita/química , Quitosana/análogos & derivados , Células-Tronco Mesenquimais/efeitos dos fármacos , Nanoestruturas/administração & dosagem , Compostos de Amônio Quaternário/química , Compostos de Amônio Quaternário/farmacologia , Engenharia Tecidual/métodos , Silicatos de Alumínio/administração & dosagem , Silicatos de Alumínio/síntese química , Antibacterianos/síntese química , Antibacterianos/farmacologia , Bentonita/administração & dosagem , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Quitosana/química , Quitosana/farmacologia , Argila , Humanos , Teste de Materiais , Células-Tronco Mesenquimais/citologia , Nanoestruturas/química
7.
Colloids Surf B Biointerfaces ; 101: 457-64, 2013 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-23010055

RESUMO

This research has designed innovative Ag/TiO(2) polysiloxane-shield nano-reactors on the PET fabric to develop novel durable bio-photocatalyst purifiers. To create these very fine nano-reactors, oppositely surface charged multiple size nanoparticles have been applied accompanied with a crosslinkable amino-functionalized polysiloxane (XPs) emulsion. Investigation of photocatalytic dye decolorization efficiency revealed a non-heterogeneous mechanism including an accelerated degradation of entrapped dye molecules into the structural polysiloxane-shield nano-reactors. In fact, dye molecules can be adsorbed by both Ag and XPs due to their electrostatic interactions and/or even via forming a complex with them especially with silver NPs. The absorbed dye and active oxygen species generated by TiO(2) were entrapped by polysiloxane shelter and the presence of silver nanoparticles further attract the negative oxygen species closer to the adsorbed dye molecules. In this way, the dye molecules are in close contact with concentrated active oxygen species into the created nano-reactors. This provides an accelerated degradation of dye molecules. This non-heterogeneous mechanism has been detected on the sample containing all of the three components. Increasing the concentration of Ag and XPs accelerated the second step beginning with an enhanced rate. Further, the treated samples also showed an excellent antibacterial activity.


Assuntos
Corantes/química , Siloxanas/química , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Catálise , Corantes/isolamento & purificação , Reagentes de Ligações Cruzadas , Peróxido de Hidrogênio/química , Cinética , Testes de Sensibilidade Microbiana , Nanopartículas , Nanotecnologia , Oxidantes/química , Tamanho da Partícula , Fotoquímica , Prata/química , Titânio/química , Difração de Raios X
8.
Colloids Surf B Biointerfaces ; 91: 280-90, 2012 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-22138117

RESUMO

Recently developing bioinspired super-hydrophobic surfaces to achieve self-cleaning properties has been driving numerous researches. However, hydrophilicity is one of the most important features of garment comfort. Therefore, accomplishing self-cleaning and stain repellency on hydrophilic surfaces would be a high topic of interest. This research is concerned with wettability mechanism; static and dynamic study of contact angle through water droplet absorption on the multiple scale nano-roughness covered by different weight ratio of oppositely charged inorganic nanoparticles and amino-functionalized polysiloxane. The results revealed that the second layer of the resin formed on the surface can show an amphiphilic hybrid block copolymer-like feature whose dual action can be intensified during water droplet absorption by the created multiple size nano-roughness. This unique structure can create a stain repellent but hydrophilic surface with exceptional advantages. The mechanism has been deeply discussed according to the evidence on droplet edge interfacial energy changes as a driving force to overcome meta-stable Cassie state on the multiple size nano-roughness with amphiphilic feature. A lotus-like nano-roughness has been also observed on the SEM micrographs. Based on a statistically approached experimental design, the effect of variant factors on droplet absorption time, static, advancing, receding contact angles and self-cleaning properties has been mathematically modeled according to the response surface methodology (RSM).


Assuntos
Nanotecnologia , Análise Espectral , Propriedades de Superfície
9.
Colloids Surf B Biointerfaces ; 88(1): 381-8, 2011 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-21813269

RESUMO

Due to the opposite surface charge of TiO(2) and silver nano-particles, at around neutral pH, it is expected that the interaction between these particles and cross-linkable polysiloxane (XPs) resin and thus their final properties would be affected by their processing technique. This paper has focused on the effect of processing design on the interaction, surface orientation and final properties of surface nano-colloidal functionalization. The results disclosed the key role of the applied process on the properties of the treated fabrics which have been well discussed through the modeling of this effect on orientations of nanoparticles on the surface. The developed models are interestingly verified by various characterizations. Applying a premixed TiO(2)/XPs colloid as an after treatment on Ag treated samples caused more enhanced stain photo-degradability and UV protection properties, while the reduction of enhanced hydrophobicity, washing durability, and stain-repellency were observed as compared to applying Ag/XPs premixed colloid on TiO(2). The role of processing on XPs stabilizing efficiency and its co-photo-catalytic function on TiO(2) nanoparticles has been concluded and deeply discussed. The appropriate processing design can be tailored in order to accomplish desirable hydrophilicity/hydrophobicity with a granted bioactivity. The results reveal that ideal bioactivity, stain photo-degradability, self-cleaning, UV protection, anti-staining properties, and washing durability can be achieved by applying a mixture of silver and XPs as an after-treatment on TiO(2) treated fabrics.


Assuntos
Siloxanas/química , Têxteis , Raios Ultravioleta , Catálise , Interações Hidrofóbicas e Hidrofílicas
10.
Colloids Surf B Biointerfaces ; 79(1): 5-18, 2010 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-20417070

RESUMO

Textiles can provide a suitable substrate to grow micro-organisms especially at appropriate humidity and temperature in contact to human body. Recently, increasing public concern about hygiene has been driving many investigations for anti-microbial modification of textiles. However, using many anti-microbial agents has been avoided because of their possible harmful or toxic effects. Application of inorganic nano-particles and their nano-composites would be a good alternative. This review paper has focused on the properties and applications of inorganic nano-structured materials with good anti-microbial activity potential for textile modification. The discussed nano-structured anti-microbial agents include TiO(2) nano-particles, metallic and non-metallic TiO(2) nano-composites, titania nanotubes (TNTs), silver nano-particles, silver-based nano-structured materials, gold nano-particles, zinc oxide nano-particles and nano-rods, copper nano-particles, carbon nanotubes (CNTs), nano-clay and its modified forms, gallium, liposomes loaded nano-particles, metallic and inorganic dendrimers nano-composite, nano-capsules and cyclodextrins containing nano-particles. This review is also concerned with the application methods for the modification of textiles using nano-structured materials.


Assuntos
Materiais Biocompatíveis/química , Nanopartículas Metálicas/química , Nanoestruturas/química , Têxteis , Antibacterianos/química , Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Bactérias/crescimento & desenvolvimento , Materiais Biocompatíveis/farmacologia , Humanos , Prata/química , Titânio/química , Óxido de Zinco/química
11.
Colloids Surf B Biointerfaces ; 81(1): 32-41, 2010 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-20675103

RESUMO

The treatment of textiles with Ag/TiO(2) nanoparticles causes a brownish color that limits the application of this otherwise good composite. In this paper, a novel method is introduced to overcome this problem. To this end, the effect of various concentrations of cross-linkable polysiloxane (XPs) and Ag mixed with XPs on TiO(2) treated fabrics has been investigated. The results reveal the performance of the method in the application of Ag and TiO(2) nanoparticles separately. In addition to the major effect of XPs on durability, the synergistic effect of applying XPs, especially Ag mixed with XPs, on TiO(2) has been confirmed. Unexpectedly, increasing the concentration of XPs not only did not limit the TiO(2) activity but allowed light absorption by the TiO(2) particles due to the low refractive index of XPs. Therefore, XPs treatment can be helpful for increasing the bioactivity and the general photo-catalytic activity of TiO(2). The results also showed that the hydrophilicity-hydrophobicity of treated substrate can be adjusted over a broad range by controlling the concentrations of these two nanoparticles and the XPs ratio. Other characteristics of treated fabrics such as antibacterial, self-cleaning, stain photo-degradability, UV protection, air permeability and washing durability were also investigated.


Assuntos
Materiais Revestidos Biocompatíveis/química , Nanocompostos/química , Têxteis/normas , Materiais Revestidos Biocompatíveis/normas , Materiais Revestidos Biocompatíveis/toxicidade , Interações Hidrofóbicas e Hidrofílicas , Teste de Materiais/métodos , Nanopartículas Metálicas/química , Fotólise/efeitos da radiação , Siloxanas/química , Prata/química , Espectrofotometria Atômica , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Indústria Têxtil/métodos , Têxteis/toxicidade , Titânio/química , Raios Ultravioleta
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