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1.
J Formos Med Assoc ; 2021 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-34593273

RESUMO

BACKGROUND/PURPOSE: Crestal bone stability, implant rigidity and occlusal loading are issues with small-diameter implants. This article demonstrates the use of two small-diameter implants replacing a missing wide edentulous site and discusses factors that may affect bone changes. METHODS: Patients who wanted to restore an edentulous space measuring from 12 to 14 mm wide in the posterior region were offered an alternative treatment option, using two narrow or regular-diameter implants instead of one wide implant. In the study, the crestal bone stability of 12 implants in 6 edentulous sites was assessed by cone beam CTs and periapical radiographs in follow-up visits for up to 4 years. RESULTS: The bone level of all the implants was stable at buccal, lingual, mesial and distal sites, with mean values < 1 mm. The average buccal bone thickness was 1.15 ± 1.07 mm and lingual was 1.86 ± 0.89 mm, meaning that implants were surrounded by a sufficient amount of bone. The good treatment outcome may be attributed to the capability of fabricating better emergence profiles, angles (Mean: 20.67 ± 7.82° at the mesial and 20.25 ± 8.23° at the distal site) and cleansable embrasures of prostheses which are key to maintaining good oral hygiene and implant health. CONCLUSION: Using two narrow or regular-diameter implants to replace a single edentulous site measured around 12-14 mm wide in posterior region seemed to be a feasible treatment option. It is especially suitable for sites with ridge atrophy and/or patients suffering from systemic diseases.

2.
J Clin Med ; 10(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34300210

RESUMO

Although a range of pharmacological interventions is available, it remains uncertain which treatment for osteoporosis is more effective. This network meta-analysis study aimed to compare different drug efficacy and safety in randomized controlled trials (RCTs) for the treatment of postmenopausal osteoporosis. PubMed, EMBASE, MEDLINE, Clinicaltrial.gov, Cochrane library, Google scholar were searched up to 31 October 2020. Randomized placebo-controlled trials that reported measures of bone mineral density (BMD) percentage change and/or numbers of adverse events of postmenopausal osteoporosis patients were included. Network meta-analysis was conducted using frequentist approach. Ninety-four RCTs comprising 15,776 postmenopausal osteoporosis females were included in the network meta-analysis. Compared with placebo, most interventions showed increase in BMD change. According to surfaces under the cumulative ranking curves (SUCRAs), strontium ranelate, fluoride, and hormone replacement therapy were most effective in increasing total hip, lumbar spine, and distal radius BMD, respectively. Parathyroid hormone (PTH) was most effective in preventing new hip fracture. When taking into account all anatomic sites, bisphosphonate (BP), monoclonal antibody (mAb), and fluoride have a balanced efficacy in increasing BMD at all sites. Considering both the effectiveness of increasing BMD and preventing hip fracture, mAb, BP, and PTH are more favorable among all interventions. The treatment effects of different medications on BMD percentage change are anatomic site-dependent. After weighing anti-osteoporosis treatment efficacy against risk of complications, BP and mAb are the more favorable interventions to increase BMD at all sites and reduce the risks of hip fracture and death.

3.
Int J Mol Sci ; 22(14)2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34298988

RESUMO

This study evaluated the biocompatibility and biological performance of novel additive-manufactured bioabsorbable iron-based porous suture anchors (iron_SAs). Two types of bioabsorbable iron_SAs, with double- and triple-helical structures (iron_SA_2_helix and iron_SA_3_helix, respectively), were compared with the synthetic polymer-based bioabsorbable suture anchor (polymer_SAs). An in vitro mechanical test, MTT assay, and scanning electron microscope (SEM) analysis were performed. An in vivo animal study was also performed. The three types of suture anchors were randomly implanted in the outer cortex of the lateral femoral condyle. The ultimate in vitro pullout strength of the iron_SA_3_helix group was significantly higher than the iron_SA_2_helix and polymer_SA groups. The MTT assay findings demonstrated no significant cytotoxicity, and the SEM analysis showed cells attachment on implant surface. The ultimate failure load of the iron_SA_3_helix group was significantly higher than that of the polymer_SA group. The micro-CT analysis indicated the iron_SA_3_helix group showed a higher bone volume fraction (BV/TV) after surgery. Moreover, both iron SAs underwent degradation with time. Iron_SAs with triple-helical threads and a porous structure demonstrated better mechanical strength and high biocompatibility after short-term implantation. The combined advantages of the mechanical superiority of the iron metal and the possibility of absorption after implantation make the iron_SA a suitable candidate for further development.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis , Âncoras de Sutura , Alanina Transaminase/sangue , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/toxicidade , Fenômenos Biomecânicos , Nitrogênio da Ureia Sanguínea , Fosfatos de Cálcio/química , Fosfatos de Cálcio/toxicidade , Sulfato de Cálcio/administração & dosagem , Sulfato de Cálcio/química , Sulfato de Cálcio/toxicidade , Creatinina/sangue , Desenho de Equipamento , Fêmur/diagnóstico por imagem , Fêmur/ultraestrutura , Ferro , Lasers , Teste de Materiais , Microscopia Eletrônica de Varredura , Estrutura Molecular , Osseointegração , Polímeros/química , Polímeros/toxicidade , Porosidade , Coelhos , Distribuição Aleatória , Resistência à Tração , Vísceras , Microtomografia por Raio-X
4.
Tissue Eng Part A ; 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-33971745

RESUMO

Tissue engineering and regenerative medicine has gradually evolved as a promising therapeutic strategy to the modern health care of aging and diseased population. In this study, we developed a novel nanofibrous scaffold and verified its application in the critical bone defect regeneration. The metformin-incorporated nano-gelatin/hydroxyapatite fibers (NGF) was produced by electrospinning, cross-linked, and then characterized by X-ray powder diffractometer and Fourier-transform infrared spectroscopy. Cytotoxicity, cell adhesion, cell differentiation, and quantitative osteogenic gene and protein expression were analyzed by bone marrow stem cells (BMSCs) from rat. Rat forearm critical bone defect model was performed for the in vivo study. The NGF were characterized by their porous structures with proper interconnectivity without significant cytotoxic effects; the adhesion of BMSCs on the NGF could be enhanced. The osteogenic gene and protein expression were upregulated. Postimplantation, the new regenerated bone in bone defect was well demonstrated in the NGF samples. We demonstrated that the metformin-incorporated NGF greatly improved healing potential on the critical-size bone defect. Although metformin-incorporated NGF had advantageous effectiveness during bone regeneration, further validation is required before it can be applied to clinical applications. Impact statement Bone is the structure that supports the rest of the human body. Critical-size bone defect hinders the regeneration of damaged bone tissues and compromises the mechanical strength of the skeletal system. Characterized by their porous structures with proper interconnectivity, the electrospinning nano-gelatin/hydroxyapatite fibrous scaffold developed in this study can greatly improve the healing potential on the critical-size bone defect. Further validation can validate its potential clinical applications.

5.
Biomolecules ; 11(1)2021 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-33467170

RESUMO

Human cartilage has relatively slow metabolism compared to other normal tissues. Cartilage damage is of great clinical consequence since cartilage has limited intrinsic healing potential. Cartilage tissue engineering is a rapidly emerging field that holds great promise for tissue function repair and artificial/engineered tissue substitutes. However, current clinical therapies for cartilage repair are less than satisfactory and rarely recover full function or return the diseased tissue to its native healthy state. Kartogenin (KGN), a small molecule, can promote chondrocyte differentiation both in vitro and in vivo. The purpose of this research is to optimize the chondrogenic process in mesenchymal stem cell (MSC)-based chondrogenic constructs with KGN for potential use in cartilage tissue engineering. In this study, we demonstrate that KGN treatment can promote MSC condensation and cell cluster formation within a tri-copolymer scaffold. Expression of Acan, Sox9, and Col2a1 was significantly up-regulated in three-dimensional (3D) culture conditions. The lacuna-like structure showed active deposition of type II collagen and aggrecan deposition. We expect these results will open new avenues for the use of small molecules in chondrogenic differentiation protocols in combination with scaffolds, which may yield better strategies for cartilage tissue engineering.


Assuntos
Anilidas/farmacologia , Reatores Biológicos , Diferenciação Celular/efeitos dos fármacos , Condrogênese/efeitos dos fármacos , Células-Tronco Mesenquimais/citologia , Ácidos Ftálicos/farmacologia , Polímeros/química , Tecidos Suporte/química , Animais , Cartilagem/efeitos dos fármacos , Cartilagem/metabolismo , Separação Celular , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Condrogênese/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Masculino , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/ultraestrutura , Modelos Biológicos , Perfusão , Proteoglicanas/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos Wistar , Coloração e Rotulagem , Fator de Crescimento Transformador beta1/farmacologia
6.
Dent Mater ; 36(11): 1437-1451, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32962852

RESUMO

OBJECTIVE: Our aim is to examine the mechanical properties of two types of additive manufactured hollow porous dental implants and 6 and 12-week bone ingrowth after insertion in animals. A 3D numerical model is also developed to show detailed tissue differentiation and to provide design guidelines for implants. METHODS: The two porous and a commercial dental implant were studied by series of in vitro mechanical tests (three-point bending, torsional, screwing torque, and sawbone pull-out tests). They also evaluated by in vivo animal tests (micro-CT analysis) and ex vivo pull-out tests. Moreover, the mechano-regulation algorithm was implemented by the 3D finite element model to predict the history of tissue differentiation around the implants. RESULTS: The results showed that the two porous implants can significantly improve osseointegration after 12-week bone healing. This resulted in good fixation and stability of implants, giving very high maximum pull-out strength 413.1 N and 493.2 N, compared to 245.7 N for the commercial implant. Also, several features were accurately predicted by the mechano-regulation model, such as transversely connected bone formation, and bone resorption occurred in the middle of implants. SIGNIFICANCE: Systematic studies on dental implants with multiple approaches, including new design, mechanical tests, animal tests, and numerical modeling, were performed. Two hollow porous implants significantly improved bone ingrowth compared with commercial implants, while maintaining mechanical strength. Also, the numerical model was verified by animal tests. It improved the efficiency of design and reduce the demand for animal sacrifice.

7.
Int J Mol Sci ; 21(12)2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32560269

RESUMO

There have been many microfluid technologies combined with hanging-drop for cell culture gotten developed in the past decade. A common problem within these devices is that the cell suspension introduced at the central inlet could cause a number of cells in each microwell to not regularize. Also, the instability of droplets during the spheroid formation remains an unsolved ordeal. In this study, we designed a microfluidic-based hanging-drop culture system with the design of taper-tube that can increase the stability of droplets while enhancing the rate of liquid exchange. A ring is surrounding the taper-tube. The ring can hold the cells to enable us to seed an adequate amount of cells before perfusion. Moreover, during the period of cell culture, the mechanical force around the cell is relatively low to prevent stem cells from differentiate and maintain the phenotype. As a result of our hanging system design, cells are designed to accumulate at the bottom of the droplet. This method enhances convenience for observation activities and analysis of experiments. Thus, this microfluid chip can be used as an in vitro platform representing in vivo physiological conditions, and can be useful in regenerative therapy.


Assuntos
Técnicas de Cultura de Células/instrumentação , Células-Tronco Mesenquimais/citologia , Técnicas Analíticas Microfluídicas/instrumentação , Materiais Biomiméticos/química , Proliferação de Células , Sobrevivência Celular , Células Cultivadas , Meios de Cultura/química , Humanos , Fenótipo
8.
BMJ Open Qual ; 9(2)2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32317274

RESUMO

AIM: Intrahospital transportation (IHT) of patients under mechanical ventilation (MV) significantly increases the risk of patient harm. A structured process performed by a well-prepared team with adequate communication among team members plays a vital role in enhancing patient safety during transportation. DESIGN AND IMPLEMENTATION: We conducted this quality improvement programme at the intensive care units of a university-affiliated medical centre, focusing on the care of patients under MV who received IHT for CT or MRI examinations. With the interventions based on the analysis finding of the IHT process by healthcare failure mode and effects analysis, we developed and implemented strategies to improve this process, including standardisation of the transportation process, enhancing equipment maintenance and strengthening the teamwork among the transportation teammates. In a subsequent cycle, we developed and implemented a new process with the practice of reminder-assisted briefing. The reminders were printed on cards with mnemonics including 'VITAL' (Vital signs, Infusions, Tubes, Alarms and Leave) attached to the transportation monitors for the intensive care unit nurses, 'STOP' (Secretions, Tubes, Oxygen and Power) attached to the transportation ventilators for the respiratory therapists and 'STOP' (Speak-out, Tubes, Others and Position) attached to the examination equipment for the radiology technicians. We compared the incidence of adverse events and completeness and correctness of the tasks deemed to be essential for effective teamwork before and after implementing the programme. RESULTS: The implementation of the programme significantly reduced the number and incidence of adverse events (1.08% vs 0.23%, p=0.01). Audits also showed improved teamwork during transportation as the team members showed increased completeness and correctness of the essential IHT tasks (80.8% vs 96.5%, p<0.001). CONCLUSION: The implementation of reminder-assisted briefings significantly enhanced patient safety and teamwork behaviours during the IHT of mechanically ventilated patients with critical illness.


Assuntos
Segurança do Paciente/normas , Respiração Artificial/métodos , Estado Terminal/terapia , Humanos , Segurança do Paciente/estatística & dados numéricos , Melhoria de Qualidade , Qualidade da Assistência à Saúde/normas , Qualidade da Assistência à Saúde/estatística & dados numéricos , Respiração Artificial/efeitos adversos , Transporte de Pacientes/métodos , Transporte de Pacientes/normas , Transporte de Pacientes/estatística & dados numéricos
9.
J Formos Med Assoc ; 119(1 Pt 3): 420-429, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31387841

RESUMO

BACKGROUND/PURPOSE: Alveolar bone loss following peri-implantitis remains a clinical challenge. We aimed to design a novel bioactive dental implant to accommodate the large bone defect caused by removal of previously failed implant. METHODS: Bio-ActiveITRI dental implant was manufactured with laser-sintered additive 3D printing technique. A 7.5 mm diameter × 7.0 mm depth osteotomy defect was created at the lateral aspect of distal femur of 20 New Zealand white rabbits to simulate the bony defect after removal of failed dental implant. One side of distal femurs was randomly selected for the commercially pure titanium NobelActive™ implant (control group) and the other side with Bio-ActiveITRI Ti6Al4V porous dental implant (ITRI group). Animals were sacrificed at 4, 8 and 12 weeks after the implants' insertion. The samples were processed for gross morphological analysis, radiographic examination, micro-CT evaluation, and mechanical testing. RESULTS: In histomorphometrical evaluation and micro-CT analysis, active new bone formation and good osseointegration within the ITRI implants were observed at the bone gap surrounding the dental implants. The biomechanical parameters in the Bio-ActiveITRI dental implants were significantly higher than those of the commercially control samples. For the Bio-ActiveITRI dental implants, the trabecular thickness decreased, while the trabecular separation and total porosity increased from the prescribed 1-month to 3-month time points; reflecting the natural remodeling of surrounding bony tissue in the Bio-ActiveITRI dental implants. CONCLUSION: The novel porous structured Bio-ActiveITRI dental implants may have a great potential for the prosthetic reconstruction where bone support is compromised after removal of a previously failed implant.


Assuntos
Implantes Dentários , Fêmur/cirurgia , Lasers , Osseointegração/fisiologia , Impressão Tridimensional , Titânio/química , Animais , Teste de Materiais , Porosidade , Coelhos , Propriedades de Superfície , Titânio/efeitos da radiação , Microtomografia por Raio-X
10.
Int J Mol Sci ; 20(23)2019 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-31795225

RESUMO

The development of a novel alloplastic graft with both osteoinductive and osteoconductive properties is still necessary. In this study, we tried to synthesize a biomimetic hydroxyapatite microspheres (gelatin/nano-hydroxyapatite microsphere embedded with stromal cell-derived factor-1: GHM-S) from nanocrystalline hydroxyapatites and to investigate their therapeutic potential and effects on bone regeneration. In this study, hydroxyapatite was synthesized by co-precipitation of calcium hydroxide and orthophosphoric acid to gelatin solution. The microbial transglutaminase was used as the agent to crosslink the microspheres. The morphology, characterization, and thermal gravimetric analysis of microspheres were performed. SDF-1 release profile and in vitro biocompatibility and relative osteogenic gene expression were analyzed, followed by in vivo micro-computed tomography study and histological analysis. The synthesized hydroxyapatite was found to be similar to hydroxyapatite of natural bone tissue. The stromal cell-derived factor-1 was embedded into gelatin/hydroxyapatite microsphere to form the biomimetic hydroxyapatite microsphere. The stromal cell-derived factor-1 protein could be released in a controlled manner from the biomimetic hydroxyapatite microsphere and form a concentration gradient in the culture environment to attract the migration of stem cells. Gene expression and protein expression indicated that stem cells could differentiate or develop into pre-osteoblasts. The effect of bone formation by the biomimetic hydroxyapatite microsphere was assessed by an in vivo rats' alveolar bone defects model and confirmed by micro-CT imaging and histological examination. Our findings demonstrated that the biomimetic hydroxyapatite microsphere can enhance the alveolar bone regeneration. This design has potential be applied to other bone defects.


Assuntos
Materiais Biomiméticos/química , Regeneração Óssea/efeitos dos fármacos , Durapatita/química , Nanocompostos/química , Animais , Materiais Biomiméticos/farmacologia , Células Cultivadas , Quimiocina CXCL12/administração & dosagem , Quimiocina CXCL12/farmacologia , Gelatina/química , Humanos , Microesferas , Ratos
11.
J Orthop Surg Res ; 14(1): 162, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31142377

RESUMO

BACKGROUND: Polymethylmethacrylate bone cement has a variety of applications in orthopedic surgery, but it also has some shortcomings such as high heat generation during polymerization and poor integration with bone tissue. In this study, a bio-composite bone cement composed of tri-calcium phosphate and chitosan as additives to acrylic bone cement was developed. Our hypothesis is that this new bio-composite bone cement has a better osteo-integration than pure polymethyl methacrylate cement. METHODS: Physiological composition, i.e., 65 wt% inorganic and 35 wt% organic components, of tri-calcium phosphate and chitosan contents was selected as degradable additives to replace acrylic bone cement. A series of properties such as exothermic temperature changes, setting time, bio-mechanical characteristics, degradation behaviors, and in vitro cytotoxicity were examined. Preliminary in vivo animal study was also performed. RESULTS: The results showed that the bio-composite bone cement exhibited lower curing temperature, longer setting time, higher weight loss and porosity after degradation, lower compressive Young's modulus, and ultimate compressive strength as compared with those of pure polymethyl methacrylate cement. Cell proliferation tests demonstrated that the bio-composite bone cement was non-cytotoxic, and the in vivo tests revealed that was more osteo-conductive. CONCLUSIONS: The results indicated that the modified chitosan/tri-calcium phosphate/polymethyl methacrylate bio-composites bone cement could be degraded gradually and create rougher surfaces that would be beneficial to cell adherence and growth. This new bio-composite bone cement has potential in clinical application. Our future studies will focus on long-term implantation to investigate the stability of the bio-composite bone cement in long-term implantation.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Cimentos Ósseos/farmacologia , Osso e Ossos/efeitos dos fármacos , Fosfatos de Cálcio/administração & dosagem , Quitosana/administração & dosagem , Animais , Materiais Biocompatíveis/metabolismo , Cimentos Ósseos/metabolismo , Osso e Ossos/metabolismo , Fosfatos de Cálcio/metabolismo , Linhagem Celular , Quitosana/metabolismo , Força Compressiva/efeitos dos fármacos , Força Compressiva/fisiologia , Teste de Materiais/métodos , Camundongos , Ratos , Ratos Sprague-Dawley
12.
Materials (Basel) ; 12(1)2019 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-30621012

RESUMO

A mismatch of elastic modulus values could result in undesirable bone resorption around the dental implant. The objective of this study was to optimize direct metal laser sintering (DMLS)-manufactured Ti6Al4V dental implants' design, minimize elastic mismatch, allow for maximal bone ingrowth, and improve long-term fixation of the implant. In this study, DMLS dental implants with different morphological characteristics were fabricated. Three-point bending, torsional, and stability tests were performed to compare the mechanical properties of different designs. Improvement of the weaker design was attempted by augmentation with a longitudinal 3D-printed strut. The osseointegrative properties were evaluated. The results showed that the increase in porosity decreased the mechanical properties, while augmentation with a longitudinal weight-bearing strut can improve mechanical strength. Maximal alkaline phosphatase gene expression of MG63 cells attained on 60% porosity Ti6Al4V discs. In vivo experiments showed good incorporation of bone into the porous scaffolds of the DMLS dental implant, resulting in a higher pull-out strength. In summary, we introduced a new design concept by augmenting the implant with a longitudinal weight-bearing strut to achieve the ideal combination of high strength and low elastic modulus; our results showed that there is a chance to reach the balance of both biologic and mechanical demands.

14.
Crit Care ; 22(1): 335, 2018 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-30522508

RESUMO

BACKGROUND: The management of complaints in the setting of intensive care may provide opportunities to understand patient and family experiences and needs. However, there are limited reports on the structured application of complaint analysis tools and comparisons between healthcare complaints in the critical care setting and other settings. METHODS: From the complaint management database of a university-affiliated medical center in Taiwan, we retrospectively identified the records of healthcare complaints to the intensive care units (ICUs) from 2008 to 2016. Complaints to the general wards in the same period were randomly selected from the database with twice the number of that of the ICU complaints. We coded, typed, and compared the complaints from the two settings according to the Healthcare Complaint Analysis Tool. RESULTS: We identified 343 complaints to the ICUs and randomly selected 686 complaints to the general wards during the 9-year study period. Most (94.7%) of the complaints to the ICUs came from the family members, whereas more complaints to the general wards came from the patients (44.2%). A total of 1529 problems (441 from ICU and 818 from general wards) were identified. Compared with the general ward complaints, in the ICU there were more complaints with multiple problems (25.1% vs. 16.9%, p = 0.002), complaints were referred more frequently to the nurses (28.1% vs. 17.5%, p < 0.001), and they focused more commonly on the care on the ICU/ward (60.5% vs. 54.2%, p = 0.029). The proportions of the three domains (clinical, management, and relationship) of complaints were similar between the ICU and general ward complaints (p = 0.121). However, in the management domain, the problems from ICU complaints focused more on the environment than on the institutional processes (90.9% vs. 74.5%, p < 0.001), whereas in the relationship domain, the problems focused more on communication (17.9% vs. 8.0%) and less on listening (34.6% vs. 46.5%) (p = 0.002) than the general ward complaints. CONCLUSIONS: A structured typing and systematic analysis of the healthcare complaints to the ICUs may provide valuable insights into the improvement of care quality, especially to the perceptions of the ICU environment and communications of the patients and their families.


Assuntos
Unidades de Terapia Intensiva/normas , Satisfação do Paciente , Quartos de Pacientes/normas , Qualidade da Assistência à Saúde/normas , Centros Médicos Acadêmicos/organização & administração , Adulto , Comunicação , Feminino , Humanos , Unidades de Terapia Intensiva/organização & administração , Masculino , Quartos de Pacientes/organização & administração , Estudos Retrospectivos , Estatísticas não Paramétricas , Taiwan
15.
Indian J Orthop ; 52(3): 315-321, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29887635

RESUMO

Background: Various surgical techniques are available to reduce chronic instability of the lateral ankle ligament complex. The most effective method for these procedures remains controversial. This report presents a surgical technique that is similar to the Broström procedure and uses a modified, nonaugmented repair technique. Materials and Methods: 38 soldiers with a history of chronic lateral ankle instability and poor ankle function underwent plication of the anterior talofibular ligament-lateral capsule complex with transosseous fixation of the calcaneofibular ligament through a fibular bone tunnel between 2004 and 2007. This study included 33 men and 5 women with a mean age of 25.6 years (range 18-36 years) at the time of surgery. Each patient was confirmed to have a history of chronic lateral ankle instability after an inversion injury, and symptoms had been noted for at least 1 year. The patients were followed up with stress radiographs, American Orthopaedic Foot and Ankle Society (AOFAS) ankle-hindfoot functional score, and the Sefton assessment system. The mean followup period was 77.6 months (range 66-89 months). Results: At the last evaluation, the talar tilt reduced from an average of 13.9° ± 2.4° before surgery to 3.8° ± 1.8° after surgery, and anterior drawer displacement reduced from 9.6 ± 2.9 mm to 2.3 ± 1.6 mm. The mean AOFAS ankle-hindfoot scale score for functional stability increased from 71.6 ± 4.0 points preoperatively to 95.6 ± 4.0 points postoperatively. As evaluated by the Sefton assessment system, 36 patients (95%) reported an excellent or good functional outcome. All patients resumed normal daily activities and active military duty after the surgery. Conclusion: The procedure described here could be considered a viable alternative option to anatomic reconstruction such as the modified Broström procedure and might be appropriate for the general population.

16.
Histol Histopathol ; 33(12): 1271-1286, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29905361

RESUMO

OBJECTIVE: With the goal to explore a new approach to treat the early degenerative lesions of hyaline cartilage, we implanted in a porcine OA model a collagen-based scaffold containing chondroprogenitor cells derived from human bone marrow mesenchymal stem cells (hBM-MSCs). EXPERIMENTAL DESIGN: Porcine knee joints were subjected to anterior cruciate ligament (ACL) transection to surgically induce OA. After 4 months, the time necessary for the development of cartilage surface damage, animals were treated either with trephination bone plug wrapped with the chondroprogenic hBM-MSCs-embedded collagen scaffold or microfractures alone. Histological and histomorphometric evaluations were performed at 5 months after surgery. RESULTS: All animals subjected to ACL transection showed osteoarthritic changes including mild lateral femoral condyle or moderate medial femoral condyle ulcerations. After 14 days' chondrogenic induction, hBM-MSCs seeded onto the scaffold showed expression of chondroprogenitor markers such as SOX9 and COMP. At 5 months after the implantation, significant differences in the quality of the regenerated tissue were found between the hBM-MSCs-embedded scaffold group and the control group. Newly generated tissue was only observed at the site of implantation with the hBM-MSCs-embedded scaffolds. Furthermore, histological examination of the generated tissue revealed evidence of cartilage-like tissue with lacuna formation. In contrast, fibrous layers or fissures were formed on the surface of the control knee joint. CONCLUSIONS: This study shows that xenogenic hBM-MSC derived chondroprogenitor scaffolds can generate new cartilage tissue in porcine articular cartilage and have the potential as a useful treatment option for osteoarthritis.


Assuntos
Colágeno , Transplante de Células-Tronco Mesenquimais/métodos , Osteoartrite , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Cartilagem Articular , Condrogênese/fisiologia , Modelos Animais de Doenças , Xenoenxertos , Humanos , Suínos
17.
J Orthop Res ; 36(10): 2633-2640, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29727018

RESUMO

The interference screw is a widely used fixation device in the anterior cruciate ligament (ACL) reconstruction surgeries. Despite the generally satisfactory results, problems of using interference screws were reported. By using additive manufacturing (AM) technology, we developed an innovative titanium alloy (Ti6 Al4 V) interference screw with rough surface and inter-connected porous structure designs to improve the bone-tendon fixation. An innovative Ti6 Al4 V interference screws were manufactured by AM technology. In vitro mechanical tests were performed to validate its mechanical properties. Twenty-seven New Zealand white rabbits were randomly divided into control and AM screw groups for biomechanical analyses and histological analysis at 4, 8, and 12 weeks postoperatively; while micro-CT analysis was performed at 12 weeks postoperatively. The biomechanical tests showed that the ultimate failure load in the AM interference screw group was significantly higher than that in the control group at all tested periods. These results were also compatible with the findings of micro-CT and histological analyses. In micro-CT analysis, the bone-screw gap was larger in the control group; while for the additive manufactured screw, the screw and bone growth was in close contact. In histological study, the bone-screw gaps were wider in the control group and were almost invisible in the AM screw group. The innovative AM interference screws with surface roughness and inter-connected porous architectures demonstrated better bone-tendon-implant integration, and resulted in stronger biomechanical characteristics when compared to traditional screws. These advantages can be transferred to future interference screw designs to improve their clinical performance. The AM interference screw could improve graft fixation and eventually result in better biomechanical performance of the bone-tendon-screw construct. The innovative AM interference screws can be transferred to future interference screw designs to improve the performance of implants. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 36:2633-2640, 2018.


Assuntos
Reconstrução do Ligamento Cruzado Anterior/instrumentação , Parafusos Ósseos , Tendões/cirurgia , Animais , Fenômenos Biomecânicos , Porosidade , Coelhos , Distribuição Aleatória , Titânio , Microtomografia por Raio-X
18.
Biomaterials ; 174: 17-30, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29763775

RESUMO

The poor regenerative capability of stem cell transplantation in the central nervous system limits their therapeutic efficacy in brain injuries. The sustained inflammatory response, lack of structural support, and trophic factors deficiency restrain the integration and long-term survival of stem cells. Instead of exogenous stem cell therapy, here we described the synthesis of nanohybrid hydrogel containing sulfated glycosaminoglycan-based polyelectrolyte complex nanoparticles (PCN) to mimic the brain extracellular matrix and control the delivery of stromal-derived factor-1α (SDF-1α) and basic fibroblast factor (bFGF) in response to matrix metalloproteinase (MMP) for recruiting endogenous neural stem cells (NSC) and regulating their cellular fate. Bioactive factors are delivered by electrostatic sequestration on PCN to amplify the signaling of SDF-1α and bFGF to regulate NSC in vitro. In in vivo ischemic stroke model, the factors promoted neurological behavior recovery by enhancing neurogenesis and angiogenesis. These combined strategies may be applied for other tissue regenerations by regulating endogenous progenitors through the delivery of different kinds of glycosaminoglycan-binding molecules.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Portadores de Fármacos/química , Glicosaminoglicanos/metabolismo , Hidrogéis/metabolismo , Nanopartículas/química , Células-Tronco Neurais/metabolismo , Polieletrólitos/química , Animais , Materiais Biomiméticos/química , Encéfalo , Quimiocina CXCL12/farmacologia , Reagentes para Ligações Cruzadas/química , Liberação Controlada de Fármacos , Fator 2 de Crescimento de Fibroblastos/farmacologia , Humanos , Ácido Hialurônico/química , Masculino , Metaloproteinases da Matriz/metabolismo , Regeneração Nervosa/efeitos dos fármacos , Neurogênese , Tamanho da Partícula , Ratos Sprague-Dawley , Transplante de Células-Tronco/métodos , Acidente Vascular Cerebral/terapia , Propriedades de Superfície
19.
Int J Mol Sci ; 19(1)2017 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-29283422

RESUMO

Diabetes mellitus is associated with damage to tendons, which may result from cellular dysfunction in response to a hyperglycemic environment. Tenocytes express diminished levels of tendon-associated genes under hyperglycemic conditions. In contrast, mechanical stretch enhances tenogenic differentiation. However, whether hyperglycemia increases the non-tenogenic differentiation potential of tenocytes and whether this can be mitigated by mechanical stretch remains elusive. We explored the in vitro effects of high glucose and mechanical stretch on rat primary tenocytes. Specifically, non-tenogenic gene expression, adipogenic potential, cell migration rate, filamentous actin expression, and the activation of signaling pathways were analyzed in tenocytes treated with high glucose, followed by the presence or absence of mechanical stretch. We analyzed tenocyte phenotype in vivo by immunohistochemistry using an STZ (streptozotocin)-induced long-term diabetic mouse model. High glucose-treated tenocytes expressed higher levels of the adipogenic transcription factors PPARγ and C/EBPs. PPARγ was also highly expressed in diabetic tendons. In addition, increased adipogenic differentiation and decreased cell migration induced by high glucose implicated a fibroblast-to-adipocyte phenotypic change. By applying mechanical stretch to tenocytes in high-glucose conditions, adipogenic differentiation was repressed, while cell motility was enhanced, and fibroblastic morphology and gene expression profiles were strengthened. In part, these effects resulted from a stretch-induced activation of ERK (extracellular signal-regulated kinases) and a concomitant inactivation of Akt. Our results show that mechanical stretch alleviates the augmented adipogenic transdifferentiation potential of high glucose-treated tenocytes and helps maintain their fibroblastic characteristics. The alterations induced by high glucose highlight possible pathological mechanisms for diabetic tendinopathy. Furthermore, the beneficial effects of mechanical stretch on tenocytes suggest that an appropriate physical load possesses therapeutic potential for diabetic tendinopathy.


Assuntos
Adipócitos/efeitos dos fármacos , Diabetes Mellitus Experimental/terapia , Glucose/farmacologia , Mecanotransdução Celular/genética , Estresse Mecânico , Tenócitos/efeitos dos fármacos , Adipócitos/metabolismo , Adipócitos/patologia , Adipogenia/efeitos dos fármacos , Adipogenia/genética , Animais , Fenômenos Biomecânicos , Proteína beta Intensificadora de Ligação a CCAAT/genética , Proteína beta Intensificadora de Ligação a CCAAT/metabolismo , Transdiferenciação Celular/efeitos dos fármacos , Diabetes Mellitus Experimental/induzido quimicamente , Diabetes Mellitus Experimental/genética , Diabetes Mellitus Experimental/patologia , Regulação da Expressão Gênica , Masculino , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , PPAR gama/genética , PPAR gama/metabolismo , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos , Ratos Sprague-Dawley , Estreptozocina , Tendões/efeitos dos fármacos , Tendões/metabolismo , Tendões/patologia , Tenócitos/metabolismo , Tenócitos/patologia
20.
BMJ Open ; 7(11): e017932, 2017 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-29101141

RESUMO

BACKGROUND: Intra-hospital transportation (IHT) might compromise patient safety because of different care settings and higher demand on the human operation. Reports regarding the incidence of IHT-related patient safety events and human failures remain limited. OBJECTIVE: To perform a retrospective analysis of IHT-related events, human failures and unsafe acts. SETTING: A hospital-wide process for the IHT and database from the incident reporting system in a medical centre in Taiwan. PARTICIPANTS: All eligible IHT-related patient safety events between January 2010 to December 2015 were included. MAIN OUTCOME MEASURES: Incidence rate of IHT-related patient safety events, human failure modes, and types of unsafe acts. RESULTS: There were 206 patient safety events in 2 009 013 IHT sessions (102.5 per 1 000 000 sessions). Most events (n=148, 71.8%) did not involve patient harm, and process events (n=146, 70.9%) were most common. Events at the location of arrival (n=101, 49.0%) were most frequent; this location accounted for 61.0% and 44.2% of events with patient harm and those without harm, respectively (p<0.001). Of the events with human failures (n=186), the most common related process step was the preparation of the transportation team (n=91, 48.9%). Contributing unsafe acts included perceptual errors (n=14, 7.5%), decision errors (n=56, 30.1%), skill-based errors (n=48, 25.8%), and non-compliance (n=68, 36.6%). Multivariate analysis showed that human failure found in the arrival and hand-off sub-process (OR 4.84, p<0.001) was associated with increased patient harm, whereas the presence of omission (OR 0.12, p<0.001) was associated with less patient harm. CONCLUSIONS: This study shows a need to reduce human failures to prevent patient harm during intra-hospital transportation. We suggest that the transportation team pay specific attention to the sub-process at the location of arrival and prevent errors other than omissions. Long-term monitoring of IHT-related events is also warranted.


Assuntos
Segurança do Paciente , Gestão de Riscos/estatística & dados numéricos , Transporte de Pacientes/normas , Adulto , Idoso , Feminino , Hospitais , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Dano ao Paciente/prevenção & controle , Estudos Retrospectivos , Taiwan
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