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1.
Bone Joint J ; 101-B(12): 1506-1511, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31786997

RESUMO

AIMS: The aim of this study was to compare the osseous reactions elicited by all-suture, polyetheretherketone (PEEK), and two different biodegradable anchors used during rotator cuff repair. PATIENTS AND METHODS: Transosseous-equivalent rotator cuff repair was performed in 73 patients. The patients were divided into two groups, in both of which two different medial-row anchors were used. In group 1, anchor A comprised 30% ß-tricalcium phosphate (TCP) + 70% fast-absorbing poly lactic-co-glycolic acid copolymer (85% polylactic acid enantiomers + 15% polyglycolic acid) and anchor B comprised all-sutures. In group 2, anchor C comprised 23% micro ß-TCP + 77% polylactic acid enantiomers and anchor D comprised PEEK polymer. There were 37 patients in group 1 and 36 patients in group 2. The presence and severity of fluid collection around anchors and healing of the rotator cuff were assessed using MRI scans, approximately one year postoperatively. The severity of the collection was graded as 0 (no perianchor fluid signal), 1 (minimal perianchor fluid), 2 (local collection of fluid), 3 (fluid collection around the whole length of the anchor but of a diameter less than twice the anchor diameter), or 4 (fluid collection around the whole length of the anchor and of a diameter greater than twice the anchor diameter). RESULTS: A perianchor fluid signal was seen in three patients (8.1%) with anchor A, four (10.8%) with anchor B, 15 (41.7%) with anchor C, and 15 (41.7%) with anchor D. The severity of the collection around anchor was grade 2:1:0:0 for anchor A, grade 2:2:0:0 for anchor B, grade 12:2:0:1 for anchor C, and grade 11:3:0:1 for anchor D (grade 1:2:3:4, respectively). The prevalence and severity of fluid formation was not significantly different between anchors A and B, and anchors C and D. However, on intergroup analysis, there were significant differences for the prevalence and severity of fluid formation between anchors in group 1 and group 2. The prevalence of failure to heal was not significant in group 1 (seven, 18.9%) or group 2 (nine, 25.0%). There was no relationship between the presence of perianchor fluid and each type of anchor, and the integrity of the rotator cuff repair, in either group. CONCLUSION: Despite the nonabsorbable nature of all-suture and PEEK anchors, all-suture anchors produced less osseous reaction after rotator cuff repair. In deciding which kind of anchor to use, consideration should be given not only to the strength of the initial fixation, but also to the postoperative biological reaction. Cite this article: Bone Joint J 2019;101-B:1506-1511.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Reação a Corpo Estranho/etiologia , Cetonas/efeitos adversos , Procedimentos Ortopédicos/instrumentação , Polietilenoglicóis/efeitos adversos , Complicações Pós-Operatórias/etiologia , Lesões do Manguito Rotador/cirurgia , Âncoras de Sutura/efeitos adversos , Adulto , Idoso , Feminino , Seguimentos , Reação a Corpo Estranho/diagnóstico por imagem , Reação a Corpo Estranho/epidemiologia , Humanos , Imagem por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/diagnóstico por imagem , Complicações Pós-Operatórias/epidemiologia , Prevalência , Estudos Prospectivos , Lesões do Manguito Rotador/diagnóstico por imagem , Resultado do Tratamento , Cicatrização
2.
Am Surg ; 85(10): 1113-1117, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31657305

RESUMO

Although recommendations help guide surgeons' mesh choice in abdominal wall reconstruction (AWR), financial and institutional pressures may play a bigger role. Standardization of an AWR algorithm may help reduce costs and change mesh preferences. We performed a retrospective review of high- and low-risk patients who underwent inpatient AWR between 2014 and 2016. High risk was defined as immunosuppression and/or history of infection/contamination. Patients were stratified by the type of mesh as biologic/biosynthetic or synthetic. These cohorts were analyzed for outcome, complications, and cost. One hundred twelve patients underwent complex AWR. The recurrence rate at two years was not statistically different between high- and low-risk cohorts. No significant difference was found in the recurrence rate between biologic and synthetic meshes when comparing both high- and low-risk cohorts. The average cost of biologic mesh was $9,414.80 versus $524.60 for synthetic. The estimated cost saved when using synthetic mesh for low-risk patients was $295,391.20. In conclusion, recurrence rates for complex AWR seem to be unrelated to mesh selection. There seems to be an excess use of biologic mesh in low-risk patients, adding significant cost. Implementing a critical process to evaluate indications for biologic mesh use could decrease costs without impacting the quality of care, thus improving the overall value of AWR.


Assuntos
Parede Abdominal/cirurgia , Materiais Biocompatíveis/economia , Redução de Custos , Sobremedicalização/economia , Telas Cirúrgicas/economia , Algoritmos , Materiais Biocompatíveis/efeitos adversos , Estudos de Coortes , Humanos , Hospedeiro Imunocomprometido , Sobremedicalização/estatística & dados numéricos , Pessoa de Meia-Idade , Readmissão do Paciente/estatística & dados numéricos , Complicações Pós-Operatórias , Recidiva , Reoperação/estatística & dados numéricos , Estudos Retrospectivos , Telas Cirúrgicas/efeitos adversos , Telas Cirúrgicas/estatística & dados numéricos
3.
Carbohydr Polym ; 224: 115162, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31472841

RESUMO

Hyaluronan (HA) films exhibit properties suitable for medical applications, but the solubility of HA limits their use in aqueous environments. This can be overcome by modifying HA with hydrophobic side groups that enable physical cross-linking. In this work, we present water insoluble free-standing films from lauroyl modified HA as novel biomaterials with properties tuneable by the degree of HA substitution. The films are homogeneous, mechanically strong, and flexible and can be sterilized by ethylenoxide. To characterize the films, we measured their thickness, dry mass, content of residual organic solvent, mechanical properties, swelling and enzymatic degradation. The safety and biodegradability of the films were tested both in-vitro and in-vivo, showing that the films are safe and that their degradation can be tailored by the degree of HA substitution.


Assuntos
Materiais Biocompatíveis/química , Ácido Hialurônico/química , Animais , Materiais Biocompatíveis/efeitos adversos , Materiais Biocompatíveis/metabolismo , Ácido Hialurônico/efeitos adversos , Ácido Hialurônico/metabolismo , Interações Hidrofóbicas e Hidrofílicas , Masculino , Fenômenos Mecânicos , Camundongos , Camundongos Endogâmicos C57BL , Segurança , Solubilidade
4.
J Mater Sci Mater Med ; 30(9): 97, 2019 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-31440845

RESUMO

Sinus elevation is a common procedure to increase bone volume in the atrophic maxilla to allow placement of dental implants. Autogenous bone is the gold standard but is limited in quantity and causes morbidity at the donor site. ß-TCP is a synthetic biomaterial commonly used in that purpose. It appears to induce a poor inflammatory response. This study aimed to evaluate the degree of edema of the sinus mucosa after sinus lift surgery according to the type of biomaterial. Forty sinuses (20 patients) were included retrospectively and divided into 2 groups according to the biomaterial that was used: synthetic biomaterial (BTCP group), natural bone (BONE group). A control group (CTRL group) was constituted by the non-grafted maxillary sinuses. Twelve measurements per sinus were realized on pre- and post-operative computed tomography and averaged to provide the sinus membrane thickness value (SM.Th). SM.Th was thicker post-operatively in the BTCP and BONE groups in comparison with the CTRL group and in comparison with pre-operative measurements. No difference was found post operatively between the BTCP and BONE groups. We found that a synthetic biomaterial (ß-TCP) induced the same degree of edema, and thus of inflammation, as natural bone. It constitutes therefore an interesting alternative to autogenous bone for maxillary sinus lifts.


Assuntos
Substitutos Ósseos/efeitos adversos , Transplante Ósseo/efeitos adversos , Fosfatos de Cálcio/efeitos adversos , Fosfatos de Cálcio/química , Sinusite Maxilar/etiologia , Levantamento do Assoalho do Seio Maxilar/efeitos adversos , Adulto , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis/efeitos adversos , Substitutos Ósseos/química , Transplante Ósseo/métodos , Implantação Dentária Endo-Óssea/efeitos adversos , Implantação Dentária Endo-Óssea/métodos , Implantes Dentários/efeitos adversos , Feminino , Humanos , Inflamação/etiologia , Inflamação/patologia , Masculino , Seio Maxilar/efeitos dos fármacos , Seio Maxilar/patologia , Sinusite Maxilar/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Levantamento do Assoalho do Seio Maxilar/métodos
5.
Curr Urol Rep ; 20(9): 49, 2019 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-31289951

RESUMO

PURPOSE OF REVIEW: Endoscopic injection of bulking agents for the treatment of vesicoureteral reflux (VUR) has become a therapeutic alternative to antibiotic prophylaxis and ureteral reimplantation. Although considered as a safe and efficient procedure, several studies have reported cases of ureteral obstruction (UO) after endoscopic correction of VUR. This review article evaluates the present VUR literature to estimate the incidence of UO following endoscopic injection of different substances, while also discussing the impact of injection technique and implant volume. RECENT FINDINGS: Twenty-five publications were identified that provided detailed information on 64 females and 32 males (age range, 7 months-48 years) that developed UO after endoscopic treatment of VUR using dextranomer/hyaluronic acid (Dx/HA), polyacrylate polyalcohol (PP), polydimethylsiloxane (PDMS), calcium hydroxyapatite (CaHA), polytetrafluoroethylene (PTFE), or collagen. There was some variation in the reported incidence of UO among these materials: Dx/HA (0.5-6.1%), PP (1.1-1.6%), PDMS (2.5-10.0%), CaHA (1.0%), and PTFE (0.3%). Postoperative UO was described following subureteric transurethral injection (STING), intraureteric hydrodistension implantation technique (HIT), combined HIT/STING and double HIT. The injected volume ranged widely, also depending on the type of bulking agent: Dx/HA (0.3-3.0 mL), PP (0.3-1.2 mL), PDMS (1.0-2.2 mL), CaHA (0.4-0.6 mL), and PTFE (1.5-2.0 mL). The timing of UO varied from immediately after the procedure to 63 months. Over half of patients showed asymptomatic hydroureteronephrosis on follow-up imaging, whereas the remaining presented with symptoms of acute UO or fever. UO remains a rare complication after endoscopic correction of VUR, generally reported in less than 1% of treated cases, which appears to be independent of the injected substance, volume, and technique. However, long-term follow-up is recommended as asymptomatic or delayed UO can occur, potentially leading to deterioration of renal function.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Endoscopia/efeitos adversos , Obstrução Ureteral/etiologia , Refluxo Vesicoureteral/cirurgia , Resinas Acrílicas/efeitos adversos , Adolescente , Adulto , Criança , Pré-Escolar , Colágeno/efeitos adversos , Dextranos/efeitos adversos , Dimetilpolisiloxanos/efeitos adversos , Durapatita/efeitos adversos , Feminino , Humanos , Ácido Hialurônico/efeitos adversos , Lactente , Injeções , Masculino , Pessoa de Meia-Idade , Politetrafluoretileno/efeitos adversos , Resultado do Tratamento , Adulto Jovem
6.
Biomed Res Int ; 2019: 2519205, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31360706

RESUMO

Dental implants are often made of titanium alloys. Implant therapy currently promises a good long-term result without impacting health; however, its success depends on many factors. In this article, the authors focus on the most common risk factors associated with metallic surgical implants. Titanium-induced hypersensitivity can lead to symptoms of implant rejection. Corrosion and biofilm formation are additional situations in which these symptoms may occur. For medical purposes, it is important to define and discuss the characteristics of metals used in implantable devices and to ensure their biocompatibility. To avoid hypersensitivity reactions to metallic dental implants, precautionary principles for primary prevention should be established.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Implantes Dentários/efeitos adversos , Metais/efeitos adversos , Materiais Biocompatíveis/uso terapêutico , Corrosão , Ligas Dentárias/efeitos adversos , Ligas Dentárias/uso terapêutico , Humanos , Metais/uso terapêutico , Fatores de Risco , Titânio/efeitos adversos , Titânio/uso terapêutico
7.
Adv Clin Exp Med ; 28(7): 961-965, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31199878

RESUMO

BACKGROUND: Tracheobronchomalacia is the most common cause of congenital airway obstruction in infants. An alternative for surgical approach (aortopexy) can be metallic airway stents. Usually, they are not considered as a first choice because of the relatively high risk of complications. Recent years have brought encouraging reports of biodegradable stents applied in children. OBJECTIVES: The aim of this study was to report our experience in the treatment of airway malacia using biodegradable stents. MATERIAL AND METHODS: Six polydioxanone (PDS), self-expanding custom-made stents (ELLA-CS) were implanted in 2 children: 3 in the patient with left main bronchus occlusion due to postpnemonectomy syndrome and 3 stents in the baby with tracheomalacia. RESULTS: Airway collapse was always relieved after stent expansion. Both patients needed repeated stenting because of limited stent lifespan. All the stents were implanted without complications through a rigid bronchoscope. The baby with stented main bronchus died because of irreversible lung lesion. CONCLUSIONS: This small study shows that biodegradable airway stents seem to be an attractive option in the treatment of tracheobronchomalacia in children. We consider this method to be safe, effective, repeatable, and reversible in small children with growing airways. As a time-buying procedure they can be especially useful in the treatment of tracheobronchomalacia.


Assuntos
Implantes Absorvíveis/efeitos adversos , Obstrução das Vias Respiratórias/terapia , Materiais Biocompatíveis , Stents , Traqueobroncomalácia/terapia , Obstrução das Vias Respiratórias/etiologia , Obstrução das Vias Respiratórias/cirurgia , Materiais Biocompatíveis/efeitos adversos , Broncomalácia/terapia , Broncoscopia , Criança , Feminino , Humanos , Lactente , Masculino , Stents/efeitos adversos , Traqueobroncomalácia/diagnóstico por imagem , Resultado do Tratamento
8.
Pediatr Neurosurg ; 54(4): 228-232, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31216552

RESUMO

OBJECTIVE: The aim of this paper was to investigate the local reactions due to the melting of absorbable plates and screws after trimming through smoothing by multiple sonic activation procedures (MSAP). BACKGROUND: Drilling or smoothing by MSAP is performed for the trimming of the absorbable plates and screws for cranial fixation in children. Compared to drilling, smoothing by MSAP is suspected to more commonly cause local tissue reactions; thus, the issue was examined herein. METHODS: For 90 children with smoothing by MSAP and 83 children with drilling procedures who underwent cranial fixation using absorbable plates and screws, the type, time of onset, and incidence of the local reactions were investigated. RESULTS: Swelling was the most common reaction, followed by inflammatory reactions with itching, heating, skin-penetrating drainage, and pus formation. The mean time of onset of the local reaction was 10.0 ± 2.3 months after surgery. Local reactions occurred in 30% of the children in the group with smoothing by MSAP, and in 7.2% of the children in the group with drilling, showing a statistically significant difference between the two groups (p < 0.001). CONCLUSION: It was concluded that drilling rather than smoothing by MSAP to change the shapes of the absorbable plates and screws in cranial fixation can reduce the local reactions.


Assuntos
Implantes Absorvíveis , Materiais Biocompatíveis/efeitos adversos , Placas Ósseas , Parafusos Ósseos , Craniossinostoses , Inflamação/etiologia , Pré-Escolar , Anormalidades Craniofaciais/cirurgia , Craniossinostoses/complicações , Craniossinostoses/cirurgia , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/etiologia , Crânio/cirurgia
9.
Int J Nanomedicine ; 14: 4211-4227, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31239676

RESUMO

Background: Cisplatin is an extensively used anti-neoplastic agent for the treatment of various solid tumors. However, a high incidence of severe ototoxicity is accompanied by its use in the clinic. Currently, no drugs or therapeutic strategies have been approved for the treatment of cisplatin-induced ototoxicity by the FDA. Purpose: The purpose of this study was to investigate the otoprotective effects of dexamethasone (DEX)-loaded silk-polyethylene hydrogel (DEX-SILK) following round window membrane administration in the cisplatin-induced ototoxicity mouse model. Methods: The morphology, gelation kinetics, viscosity and secondary structure of the DEX-SILK hydrogel were analyzed. DEX concentration in the perilymph was tested at different time points following hydrogel injection on the RWM niche. Cultured cells (HEI-OC1), organ of Corti explants (C57/BL6, P0-2), and cisplatin-induced hearing loss mice model (C57/BL6) were used as in vitro and in vivo models for investigating the otoprotective effects of DEX-SILK hydrogel against cisplatin. Results: Encapsulation of DEX with a loading of 8% (w/v) did not significantly change the silk gelation time, and DEX was evenly distributed in the Silk-PEG hydrogel as visualized by scanning electron microscopy (SEM). The concentration of Silk majorly influenced DEX distribution, morphological characteristics, viscosity, and gelation time. The optimized DEX-SILK hydrogel (8% w/v loading, 15% silk concentration, 10 µl) was administered directly onto the RWM of the guinea pigs. The DEX concentration in the perilymph was maintained above 1 µg/ml for at least 21 days for the DEX-SILK, while it was maintained for less than 6 h in the control sample of free DEX. DEX-SILK (5-60 ng/ml) exhibited significant protective effects against cisplatin-induced cellular ototoxicity and notably reduced the production of reactive oxygen species (ROS). Eventually, pretreatment with DEX-SILK effectively preserved outer hair cells in the cultured organ of Corti explants and demonstrated significant hearing protection at 4, 8, and 16 kHz in the cisplatin-induced hearing loss mice as compared to the effects noted following pretreatment with DEX. Conclusion: These results demonstrated the clinical value of DEX-SILK for the therapy of cisplatin-induced ototoxicity.


Assuntos
Cisplatino/efeitos adversos , Dexametasona/farmacologia , Orelha/patologia , Hidrogéis/química , Injeções , Polietilenoglicóis/química , Seda/química , Animais , Materiais Biocompatíveis/efeitos adversos , Bombyx , Linhagem Celular , Cóclea/efeitos dos fármacos , Cóclea/patologia , Dexametasona/uso terapêutico , Modelos Animais de Doenças , Liberação Controlada de Fármacos , Cobaias , Perda Auditiva/induzido quimicamente , Perda Auditiva/tratamento farmacológico , Camundongos Endogâmicos C57BL , Substâncias Protetoras/farmacologia , Espécies Reativas de Oxigênio/metabolismo
10.
BMC Musculoskelet Disord ; 20(1): 257, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-31138200

RESUMO

BACKGROUND: Different substances are combined to compensate for each other's drawbacks and create an appropriate biomaterial. A novel Polyvinyl alcohol (PVA)/chitosan (CS) porous hydrogel was designed and applied to the treatment of osteochondral defects. METHODS: Hydrogels of various PVA/CS ratios were tested for physiochemical and mechanical properties in addition to cytotoxicity and biocompatibility. The hydrogels with the best PVA/CS ratio were used in the animal study. Osteochondral defects were created at the articular cartilage of 18 rabbits. They were assigned to different groups randomly (n = 6 per group): the osteochondral defect only group (control group), the osteochondral defect treated with hydrogel group (HG group), and the osteochondral defect treated with hydrogel loaded with bone marrow mesenchymal stem cells (BMSCs) group (HG-BMSCs group). The cartilage was collected for macro-observation and histological evaluation at 12 weeks after surgery. RESULTS: The Hydrogel with PVA/CS ratio of 6:4 exhibited the best mechanical properties; it also showed stable physical and chemical properties with porosity and over 90% water content. Furthermore, it demonstrated no cytotoxicity and was able to promote cell proliferation. The HG-BMSCs group achieved the best cartilage healing. CONCLUSIONS: The novel PVA/CS porous composite hydrogel could be a good candidate for a tissue engineering material in cartilage repair.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Doenças das Cartilagens/terapia , Hidrogéis/efeitos adversos , Transplante de Células-Tronco Mesenquimais , Tecidos Suporte/efeitos adversos , Animais , Doenças das Cartilagens/patologia , Cartilagem Articular/citologia , Cartilagem Articular/lesões , Cartilagem Articular/fisiologia , Proliferação de Células/efeitos dos fármacos , Quitosana/administração & dosagem , Quitosana/efeitos adversos , Condrogênese/efeitos dos fármacos , Terapia Combinada/efeitos adversos , Terapia Combinada/métodos , Modelos Animais de Doenças , Humanos , Hidrogéis/administração & dosagem , Masculino , Teste de Materiais , Células-Tronco Mesenquimais/efeitos dos fármacos , Células-Tronco Mesenquimais/fisiologia , Álcool de Polivinil/administração & dosagem , Álcool de Polivinil/efeitos adversos , Porosidade , Coelhos , Regeneração/efeitos dos fármacos , Testes de Toxicidade , Resultado do Tratamento , Cicatrização/efeitos dos fármacos , Cicatrização/fisiologia
11.
Bioelectrochemistry ; 129: 79-89, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31125924

RESUMO

When implantable recording devices for brain or neural electrical activity are designed, the number of available materials for electrodes is quite limited. The material must be biocompatible with respect to ISO10993, its electrochemical properties must remain stable and the response of cells or tissues can be mitigated, especially on the glial scar. This involves electrode characterization pre- implantation and impedance spectroscopy during chronic implantation, in order to evaluate both electrode properties and performance. This study was aimed at a comparison of the long-term behavior of a nanostructured boron-doped diamond (BDD) with a nanostructured Platinum Iridium (PtIr) electrode. Firstly, a batch of cortical grids with bare and modified contacts (2 mm in diameter) was engineered for implantation. Secondly a miniature swine model was developed. This study highlighted the predominant role of electrode surface roughness on the quality of recordings. Rough PtIr contacts and BDD coated ones showed comparable behavior after three-month implantation with a slight increase of the modulus of the impedance and a tissue capsule. Nevertheless, immunohistochemistry analysis did not exhibit either a toxic or irritation reaction. With regard to biocompatibility, promising long term results are shown for both materials.


Assuntos
Materiais Biocompatíveis/química , Boro/química , Diamante/química , Eletrodos Implantados , Nanoestruturas/química , Animais , Materiais Biocompatíveis/efeitos adversos , Boro/efeitos adversos , Encéfalo/ultraestrutura , Diamante/efeitos adversos , Espectroscopia Dielétrica , Técnicas Eletroquímicas , Eletrodos Implantados/efeitos adversos , Proteína Glial Fibrilar Ácida/análise , Nanoestruturas/efeitos adversos , Nanoestruturas/ultraestrutura , Suínos , Porco Miniatura
12.
Undersea Hyperb Med ; 46(2): 207-210, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31051067

RESUMO

Dermal injection of fillers is a popular and relatively safe aesthetic procedure. Severe complications are rare, but they do occur. One of the most threatening complications after dermal filler injection is skin necrosis due to vascular occlusion. Different treatment options are available, including the use of hyperbaric oxygen (HBO2) therapy. A 46-year-old female received facial dermal filler injections with calcium hydroxylapatite at an aesthetic clinic. A few days after injection she developed a burning pain, numbness of the skin and white discoloration in the injected area. Two days after injection treatment was started with hyaluronidase and warm compresses. In addition, the patient received prednisolone, sildenafil and nifedipine. After the start of these treatments, the pain, numbness and discoloration of the skin persisted. Because of dermal ischemia and to improve healing she was referred for HBO2. Treatment consisted of 10 sessions of 100% oxygen for 90 minutes in a multiplace chamber at 2.5 atmospheres absolute pressure. During HBO2 the discoloration resolved, pain and numbness disappeared, and the tissue healed completely. After a six-month follow-up she had an excellent cosmetic outcome. Given the pathophysiologic mechanisms of vascular complications after dermal filler injection, HBO2 should be considered when treating these complications.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Preenchedores Dérmicos/efeitos adversos , Face/irrigação sanguínea , Oxigenação Hiperbárica , Isquemia/terapia , Pele/irrigação sanguínea , Feminino , Humanos , Isquemia/etiologia , Pessoa de Meia-Idade , Fotografação
13.
Regul Toxicol Pharmacol ; 106: 81-89, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31039384

RESUMO

A multiple endpoint analysis (MEA) approach on human reconstructed corneal epithelium (HCE) model has been applied to assess the biocompatibility (cytotoxicity and irritation potential) of medical devices (MD): ophthalmology literature clearly shows the need to better assess these products to exclude any potential chronic damage to the ocular surface. Preserved eye drops (Artelac Multidose, Optive multidose and Artelac Rebalance Multidose) and the same without preservative (Artelac Edo, Optive Unidose, Artelac Rebalance Unidose) and Thealoz Duo were tested after acute (24 h + 16 h post incubation) and repeated (2 applications/day for 72 h) exposure using BAK 0.01% as positive control on HCE. Cellular viability, trans-epithelial electrical resistance measurements, LDH release and occludin gene expression were evaluated for each product to discriminate the potential toxicity of preservatives. The BAK 0.01% toxicity on HCE was confirmed following both exposures. The analysis of the same parameters reveals that the 72 h exposure was suitable to identify toxicity and damages to the ocular surface even for 'soft' preserved MD. The results confirm the reliability, sensitivity and predictivity of the MEA on HCE in detecting subclinical signs of cellular toxicity: 'soft' preservatives resulted toxics suggesting that delayed toxicity should be integral part of the biocompatibility assessment of ophthalmic formulations intended for long-term use.


Assuntos
Compostos de Benzalcônio/farmacologia , Materiais Biocompatíveis/farmacologia , Epitélio Anterior/efeitos dos fármacos , Irritantes/farmacologia , Soluções Oftálmicas/farmacologia , Conservantes Farmacêuticos/farmacologia , Compostos de Benzalcônio/efeitos adversos , Materiais Biocompatíveis/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Equipamentos e Provisões , Humanos , Irritantes/efeitos adversos , Soluções Oftálmicas/efeitos adversos , Conservantes Farmacêuticos/efeitos adversos
14.
Mater Sci Eng C Mater Biol Appl ; 101: 640-649, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029358

RESUMO

In this study, type I collagen membranes were prepared using oligomeric proanthocyanidins (OPCs) as the cross-linking agent. The fabricated materials were evaluated to be applied as guided tissue regeneration membranes for periodontal defects. The mechanical strength of the cross-linked collagen membranes, namely OPCs-Col films, using different concentrations of OPCs ranged from 30 to 60 kPa. The cross-linked collagen membranes had better thermal stability than non-cross-linked one and could effectively resist the decomposition in collagenase solution as long as fifty days. The results of material characterization showed that 10% OPCs-Col film was ideal for our purpose. In vitro study using L929 and MG-63 cells revealed that 10% OPCs-Col film had great biocompatibility while OPC was demonstrated to be not cytotoxic as glutaraldehyde and genipin but even promote L929 cells. The material was further studied for in vivo studies with two models, subcutaneous and cranium defects in rat. The subcutaneous test showed that the regeneration membrane degraded till one month and the inflammatory response also reduced with implantation time. When implanted into the cranium defect, no lesions of the brain were caused and new bone tissue was observed inside the material. The results of in vivo studies showed that the synthesized membrane was helpful for tissue regeneration with long degradation time. The tissue regeneration membranes can barrier the rapid growing soft tissue, in order to save the capacity for the growth of neo bone.


Assuntos
Materiais Biocompatíveis/química , Colágeno/química , Regeneração Tecidual Guiada Periodontal/métodos , Proantocianidinas/química , Animais , Materiais Biocompatíveis/efeitos adversos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Proantocianidinas/efeitos adversos , Ratos
15.
Mater Sci Eng C Mater Biol Appl ; 101: 660-673, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31029360

RESUMO

Since large bone defects cannot be healed by the body itself, continuous effort is put into the development of 3D scaffolds for bone tissue engineering. One method to fabricate such scaffolds is selective laser sintering (SLS). However, there is a lack of solvent-free prepared microparticles suitable for SLS. Hence, the aim of this study was to develop a solvent-free polylactide/calcium carbonate composite powder with tailored material properties for SLS. Four composite powders with a composition of approximately 75 wt% polylactide (PLLA as well as PDLLA) and 25 wt% calcium carbonate (calcite) were prepared by a milling process based on GMP standards. Four different grades of polylactide were chosen to cover a broad inherent viscosity range of 1.0-3.6 dl/g. The composite material with the lowest inherent viscosity (1.0 dl/g) showed the best processability by SLS. This was caused by the small polymer particle diameter (50 µm) and the small zero-shear melt viscosity (400 Pa·s), which led to fast sintering. The SLS process parameters were developed to achieve low micro-porosity (approx. 2%) and low polymer degradation (no measurable decrease of the inherent viscosity). A biaxial bending strength of up to 75 MPa was achieved. Cell culture assays indicated good viability of MG-63 osteoblast-like cells on the SLS specimens. Finally, the manufacture of 3D scaffolds with interconnected pore structure was demonstrated. After proving the biocompatibility of the material, the developed scaffolds could have great potential to be used as patient-specific bone replacement implants.


Assuntos
Materiais Biocompatíveis/química , Carbonato de Cálcio/química , Poliésteres/química , Engenharia Tecidual/métodos , Tecidos Suporte/química , Materiais Biocompatíveis/efeitos adversos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Viscosidade
16.
Int J Mol Sci ; 20(5)2019 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-30857355

RESUMO

Three-dimensional (3D) printing technologies can be widely used for producing detailed geometries based on individual and particular demands. Some applications are related to the production of personalized devices, implants (orthopedic and dental), drug dosage forms (antibacterial, immunosuppressive, anti-inflammatory, etc.), or 3D implants that contain active pharmaceutical treatments, which favor cellular proliferation and tissue regeneration. This review is focused on the generation of 3D printed polymer-based objects that present antibacterial properties. Two main different alternatives of obtaining these 3D printed objects are fully described, which employ different polymer sources. The first one uses natural polymers that, in some cases, already exhibit intrinsic antibacterial capacities. The second alternative involves the use of synthetic polymers, and thus takes advantage of polymers with antimicrobial functional groups, as well as alternative strategies based on the modification of the surface of polymers or the elaboration of composite materials through adding certain antibacterial agents or incorporating different drugs into the polymeric matrix.


Assuntos
Anti-Infecciosos/química , Materiais Biocompatíveis/química , Celulose/análogos & derivados , Impressão Tridimensional , Animais , Anti-Infecciosos/farmacologia , Materiais Biocompatíveis/efeitos adversos , Humanos
17.
Toxicol Pathol ; 47(3): 390-400, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30712470

RESUMO

Absorbable metallic implants have been under investigation for more than a century. Animal and human studies have shown that magnesium (Mg) alloys can be safely used in bioresorbable scaffolds. Several cardiovascular and orthopedic biodegradable metallic devices have recently been approved for use in humans. Bioresorbable Mg implants present many advantages when compared to bioabsorbable polymer or nonabsorbable metallic implants, including similar strength and mechanical properties as existing implant-grade metals without the drawbacks of permanence or need for implant removal. Imaging visibility is also improved compared to polymeric devices. Additionally, with Mg-based cardiovascular stents, the risk of late stent thrombosis and need for long-term anti-platelet therapy may be reduced as the host tissue absorbs the Mg degradation products and the morphology of the vessel returns to a near-normal state. Absorbable Mg implants present challenges in the conduct of preclinical animal studies and interpretation of pathology data due to their particular degradation process associated with gas production and release of by-products. This article will review the different uses of Mg implants, the Mg alloys, the distinctive degradation features of Mg, and the challenges confronting pathologists at tissue collection, fixation, imaging, slide preparation, evaluation, and interpretation of Mg implants.


Assuntos
Ligas/efeitos adversos , Materiais Biocompatíveis/efeitos adversos , Segurança de Equipamentos/métodos , Magnésio/efeitos adversos , Teste de Materiais/métodos , Próteses e Implantes/efeitos adversos , Ligas/química , Animais , Materiais Biocompatíveis/normas , Segurança de Equipamentos/instrumentação , Imageamento Tridimensional , Magnésio/química , Teste de Materiais/instrumentação , Próteses e Implantes/normas
18.
J Craniofac Surg ; 30(3): e241-e243, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30730518

RESUMO

Cranioplasty is a common procedure in neurosurgical practice. However, some complications may occur after the operation. We here presented a case of bilateral skull defect and underwent cranioplasty with polyetheretherketone (PEEK) prosthesis. The patient developed epidural effusion on both sides 7 days after surgery. The effusion was light yellow and transparent, and laboratory examinations revealed normal glucose level, negative bacteriological results, and increased IgG protein concentration. The effusion disappeared after treatment with dexamethasone and drainage. We speculated that the epidural effusion was because of delayed type allergic reactions after PEEK cranioplasty. However, further studies are needed to investigate its related mechanisms.


Assuntos
Materiais Biocompatíveis/efeitos adversos , Hipersensibilidade/etiologia , Cetonas/efeitos adversos , Polietilenoglicóis/efeitos adversos , Próteses e Implantes/efeitos adversos , Crânio/cirurgia , Adulto , Espaço Epidural , Humanos , Hipersensibilidade/terapia , Cetonas/imunologia , Masculino , Complicações Pós-Operatórias/etiologia , Procedimentos Cirúrgicos Reconstrutivos/efeitos adversos , Crânio/lesões
19.
J Arthroplasty ; 34(5): 965-973, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30777624

RESUMO

BACKGROUND: There is a paucity of reports on osteolysis associated with tibial screw fixation in cementless total knee arthroplasty (TKA), and the pathophysiology is not clear. This study aimed to describe the pathology related to screw track osteolysis around the tibia in cementless TKA. METHODS: The study cohort comprised 100 revised cementless TKAs with tibial screw fixation. Screw track osteolysis and various screw angles were analyzed radiologically. Tissue samples from the joint capsule and the osteolytic cavity were investigated for metal/polyethylene wear. The type of tissue response was determined using immunohistochemistry. Retrieved tibial polyethylene inserts were analyzed for screw hole impression and mode of wear. Tissue metal content was measured by inductively coupled plasma optical emission spectrometry. Electrochemical reactions between the tibial tray and the cancellous screws were investigated. RESULTS: Radiological analysis showed screw track osteolysis predominantly at the medial aspect of the tibial component, and the severity of osteolysis positively correlated with smaller medial proximal tibial screw angles. Osteolysis was associated with high titanium concentrations but not with polyethylene particles. An open circuit potential between the screw and the tibial base plate was measured. Necrosis, osteolytic cyst formation and macrophages, T and B cells, and dendritic cells were present. CONCLUSION: The present study highlights the risk for screw track osteolysis in cementless TKA with screw fixation. Our data collectively suggest that titanium wear may contribute to screw track osteolysis in the cementless TKA design. The contribution of screw angles is difficult to prove.


Assuntos
Artroplastia do Joelho/efeitos adversos , Parafusos Ósseos/efeitos adversos , Prótese do Joelho/efeitos adversos , Osteoartrite do Joelho/cirurgia , Osteólise/patologia , Tíbia/cirurgia , Idoso , Idoso de 80 Anos ou mais , Artroplastia do Joelho/métodos , Materiais Biocompatíveis/efeitos adversos , Cimentos para Ossos , Cimentação , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Joelho/patologia , Osteólise/etiologia , Desenho de Prótese , Falha de Prótese , Tíbia/patologia , Titânio/efeitos adversos
20.
Toxicol Pathol ; 47(3): 358-378, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30700220

RESUMO

Bioabsorbable implants can be advantageous for certain surgical tissue bioengineering applications and implant-assisted tissue repair. They offer the obvious benefits of nonpermanence and eventual restoration of the native tissue's biomechanical and immunological properties, while providing a structural scaffold for healing and a route for additional therapies (i.e., drug elution). They present unique developmental, imaging, and histopathological challenges in the conduct of preclinical animal studies and in interpretation of pathology data. The bioabsorption process is typically associated with a gradual decline (over months to years) in structural strength and integrity and may also be associated with cellular responses such as phagocytosis that may confound interpretation of efficacy and safety end points. Additionally, as these implants bioabsorb, they become increasingly difficult to isolate histologically and thus imaging modalities such as microCT become very valuable to determine the original location of the implants and to assess the remodeling response in tandem with histopathology. In this article, we will review different types of bioabsorbable implants and commonly used bioabsorbable materials; additionally, we will address some of the most common challenges and pitfalls confronting histologists and pathologists in collecting, handling, imaging, preparing tissues through histology, evaluating, and interpreting study data associated with bioabsorbable implants.


Assuntos
Implantes Absorvíveis/efeitos adversos , Materiais Biocompatíveis/efeitos adversos , Segurança de Equipamentos/métodos , Teste de Materiais/métodos , Patologia/métodos , Tecidos Suporte/efeitos adversos , Implantes Absorvíveis/normas , Animais , Materiais Biocompatíveis/normas , Segurança de Equipamentos/instrumentação , Técnicas Histológicas/métodos , Humanos , Processamento de Imagem Assistida por Computador , Teste de Materiais/instrumentação , Especificidade da Espécie , Engenharia Tecidual , Tecidos Suporte/normas
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