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1.
Macromol Rapid Commun ; 44(22): e2300408, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37581256

RESUMO

Water filtration is an important application to ensure the accessibility of clean drinking water. As requirements and contaminants vary on a local level, adjustable filter devices and their evaluation with contaminants are required. Within this work, modular filter devices are designed featuring an adjustable surface functionalization. For this purpose, 3D-printed structures are created consisting of bio-based poly(lactic acid) (PLA) that are manufactured by extrusion printing. The surface of PLA is activated with amino groups that are used to install xanthates as chain transfer agents. Subsequently, photo-iniferter (PI) polymerization is used to create cationic polymer brushes on the surface of PLA substrates. Multiple surface characterization techniques are employed to prove successful growth of polymer brushes on PLA. After initial optimization studies on flat surfaces, filter devices are printed, functionalized, and used to remove bacteria from contaminated water. Significant reduction of the number of microorganisms is detected after filtration (single filtration or cycling) and contaminating organism can also be removed from freshwater samples by simple incubation with a 3D-printed filter. The herein developed setup for producing functional filter devices and probing their performance in affinity filtration is a useful platform technology, enabling the rapid testing of polymer brushes for such applications.


Assuntos
Anti-Infecciosos , Água , Água/química , Polimerização , Polímeros/química , Poliésteres/química , Impressão Tridimensional
2.
Clin Oral Investig ; 25(6): 3853-3860, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33409692

RESUMO

OBJECTIVE: The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) pandemic has created hitherto unknown challenges for healthcare systems and patient care. This study aimed to analyze its influence on patient care and healthcare management in oral and maxillofacial surgery (OMFS) in Germany. MATERIALS AND METHODS: A nationwide survey of the German Association of Oral and Maxillofacial Surgery was performed. Individual questionnaires containing 10 questions for university as well as non-university hospitals and 15 questions for private practices (PPs) for OMFS were created to collect data for patient numbers and surgical procedures conducted, usage of personal protection equipment (PPE), SARS-CoV-2 tests, and economic aspects. RESULTS: Fifty-four hospitals and 240 PPs participated in the study. The reduction in ward capacities and number of surgical procedures ranged from 17 to 78%. PPE consisted of standard surgical masks (58% hospitals, 64% PPs) and FFP2/N95/KN95 respirators (45% hospitals, 48% PPs). Preoperative SARS-CoV-2 tests were more frequently performed in hospitals (34% vs 2%). At PPs, turnover for medical and dental procedures billed to the public insurance had reduced to 58.81% and 62.43%, respectively, of the corresponding values for 2019, and 58.75% of the PPs had applied for short-time allowances. CONCLUSION: With the exception of some elective procedures, primary patient care in OMFS has been assured during the pandemic. However, the immense economic burden on hospitals and PPs cannot be conclusively assessed at this point. CLINICAL RELEVANCE: For OMFS, the German healthcare system has shown the ability to adapt to emergency situations such as the SARS-CoV-2 pandemic. Adequate surgical capacities in OMFS are necessary even during pandemics.


Assuntos
COVID-19 , Cirurgia Bucal , Alemanha/epidemiologia , Hospitais , Humanos , Pandemias , Prática Privada , SARS-CoV-2 , Inquéritos e Questionários
3.
BMC Vet Res ; 12(1): 283, 2016 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-27938359

RESUMO

BACKGROUND: Many patients with a congenital extrahepatic portosystemic shunt (PSS) do not tolerate an immediate shunt closure. Therefore, slow progressive techniques were developed. To evaluate the success of shunt closure diagnostic imaging is essential to identify possible residual blood flow through the shunt vessel. There is a lack of information about the reliability of computed tomography angiography (CTA) for evaluating residual flow through a PSS after treatment. The purpose of this prospective study was to compare the results of CTA with splenoportography. Three months after cellophane banding CTA and splenoportography were performed in 20 dogs and reviewed by three independent examiners, respectively. In both imaging modalities the presences of a residual shunt was judged as present or absent and the extent of visibility of portal vasculature was recorded. RESULTS: Based on the evaluation of the splenoportography residual flow through shunt was present in 6 dogs. The classification of residual shunt present or absent showed a substantial to perfect agreement (κ = 0.65-1.00) between the observers in splenoportography and a slight to moderate agreement (κ = 0.11-0.51) for CTA. Sensitivity and specificity varied between 0.50 and 1.00 and 0.57-0.85, respectively. Significant correlation between CTA and splenoportography for the classification of residual shunt was present only in one observer but not in the other two. CONCLUSION: More studies were classified as residual shunt positive with CTA compared to splenoportography. It remains unclear which methods do reflect reality better and thus which method is superior. The greater inter-rater agreement for splenoportography suggests a greater reliability of this technique.


Assuntos
Angiografia por Tomografia Computadorizada/veterinária , Doenças do Cão/diagnóstico por imagem , Veia Porta/anormalidades , Portografia/veterinária , Malformações Vasculares/veterinária , Animais , Celofane , Doenças do Cão/cirurgia , Cães , Feminino , Masculino , Veia Porta/diagnóstico por imagem , Veia Porta/cirurgia , Estudos Prospectivos , Malformações Vasculares/diagnóstico por imagem , Malformações Vasculares/cirurgia
4.
Am J Orthod Dentofacial Orthop ; 139(4 Suppl): S109-16, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21435528

RESUMO

INTRODUCTION: The aims of this study were to analyze changes in bone density of the midpalatal suture after surgically assisted rapid palatal expansion (SARPE) with the bone-borne Dresden Distractor (DD; ITU, Dresden, Germany) via computed tomography (CT) and to compare of preoperative surgical findings with a control group. METHODS: Sixteen adult patients (mean age 24.5 years) underwent axial CT scans before and 7 months after SARPE. CT image fusion was performed for the midpalatal suture bone. Sixty-six controls (mean age 25.7 years) served for comparing age-related bone density. Bone structure and density were assessed in the coronal plane at the anterior, median, and posterior levels. RESULTS: Highest density was found in the posterior part (1046 Hounsfield units [HU]) before expansion. Seven months after SARPE, bone density was 48% (anterior), 53% (median), and 75% (posterior) compared with preoperative values. The control group showed fairly equal Hounsfield units (889 HU to 900 HU) in all parts. CONCLUSIONS: Seven months after SARPE, the midpalatal suture's density achieves just one half to three quarters of the pretreatment values. To maintain the resistance against forces from the unsplit posterior part, the retention time should be lengthened.


Assuntos
Densidade Óssea , Má Oclusão/cirurgia , Técnica de Expansão Palatina , Palato Duro/fisiopatologia , Palato Duro/cirurgia , Adolescente , Adulto , Estudos de Casos e Controles , Suturas Cranianas/diagnóstico por imagem , Suturas Cranianas/patologia , Análise do Estresse Dentário , Feminino , Humanos , Masculino , Má Oclusão/diagnóstico por imagem , Má Oclusão/patologia , Procedimentos Cirúrgicos Ortognáticos , Osteogênese por Distração , Palato Duro/diagnóstico por imagem , Palato Duro/patologia , Estudos Prospectivos , Reprodutibilidade dos Testes , Prevenção Secundária , Estatísticas não Paramétricas , Tomografia Computadorizada por Raios X , Adulto Jovem
5.
Langmuir ; 26(6): 4095-102, 2010 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-20163081

RESUMO

The interaction between polyethylenimine (PEI) and phospholipid bilayers plays an important role in several biophysical applications such as DNA transfection of target cells. Despite considerable investigation into the nature of the interaction between PEI and phospholipid bilayers, the physical process remains poorly understood. In this paper, we study the impact of PEI on 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) vesicles as a function of salt concentration using several techniques including dynamic (DLS) and static (SLS) light scattering, differential scanning calorimetry (DSC), and nuclear magnetic resonance (NMR). At low salt concentration, vesicles aggregate, leading to the formation of stable clusters whose final size depends on the PEI concentration. At high salt concentration the system does not aggregate; DSC and NMR data reveal that the PEI penetrates into the bilayer, and SLS measurements are consistent with PEI crossing the bilayer. The transfectional ability of PEI is discussed in terms of these results.


Assuntos
Bicamadas Lipídicas , Fosfolipídeos/química , Polietilenoimina/química , Varredura Diferencial de Calorimetria , DNA/genética , Espectroscopia de Ressonância Magnética , Transfecção
6.
BMC Mol Cell Biol ; 21(1): 64, 2020 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-32917131

RESUMO

BACKGROUND: It has been demonstrated that von Willebrand factor (VWF) mediated platelet-endothelium and platelet-platelet interactions are shear dependent. The VWF's mobility under dynamic conditions (e.g. flow) is pivotal to platelet adhesion and VWF-mediated aggregate formation in the cascade of VWF-platelet interactions in haemostasis. RESULTS: Combining microfluidic tools with fluorescence and reflection interference contrast microscopy (RICM), here we show, that specific deletions in the A-domains of the biopolymer VWF affect both, adhesion and aggregation properties independently. Intuitively, the deletion of the A1-domain led to a significant decrease in both adhesion and aggregate formation of platelets. Nevertheless, the deletion of the A2-domain revealed a completely different picture, with a significant increase in formation of rolling aggregates (gain of function). We predict that the A2-domain effectively 'masks' the potential between the platelet glycoprotein (GP) Ib and the VWF A1-domain. Furthermore, the deletion of the A3-domain led to no significant variation in either of the two functional characteristics. CONCLUSIONS: These data demonstrate that the macroscopic functional properties i.e. adhesion and aggregate formation cannot simply be assigned to the properties of one particular domain, but have to be explained by cooperative phenomena. The absence or presence of molecular entities likewise affects the properties (thermodynamic phenomenology) of its neighbours, therefore altering the macromolecular function.


Assuntos
Plaquetas/metabolismo , Plaquetas/fisiologia , Adesividade Plaquetária/fisiologia , Agregação Plaquetária/fisiologia , Fator de von Willebrand/metabolismo , Biopolímeros/metabolismo , Linhagem Celular , Fluorescência , Células HEK293 , Hemostasia/fisiologia , Humanos , Microfluídica/métodos , Microscopia/métodos , Complexo Glicoproteico GPIb-IX de Plaquetas/metabolismo
7.
Chemphyschem ; 10(16): 2858-61, 2009 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-19598193

RESUMO

Cell and vesicle adhesion is believed to be dictated by the balance between a local interaction potential, which represents the sum of all attractive and repulsive forces and the elastic energy. Changing the mechanical properties of the membrane therefore offers a sensitive tool to control vesicle adhesion. Here, we take advantage of the dramatic changes in area per molecule, fluidity and compressibility during lipid phase transition to alter vesicle adhesion. We demonstrate that driving a giant unilamellar vesicle (GUV) through its phase transition by increasing the temperature leads to a wetting transition of the vesicle onto a pure glass substrate. Analysing vesicle shape and the adhesion area shows that the vesicle is strongly adhered and that the wetting process follows exactly the melting transition of the lipid membrane. We provide evidence that the linear relationship between change in area and enthalpy during lipid phase transition can be applied to individual vesicles as its application correctly extracts the heat capacity profile of DPPC vesicles from our adhesion experiments. It clearly demonstrates that this wetting process is driven by the coupling of mechanical and thermodynamic properties in lipid membranes.


Assuntos
Lipossomas Unilamelares/química , Transição de Fase , Temperatura , Termodinâmica , Fatores de Tempo
8.
Chemphyschem ; 10(16): 2852-7, 2009 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-19830769

RESUMO

Membrane budding has been extensively studied as an equilibrium process attributed to the formation of coexisting domains or changes in the vesicle area-to-volume ratio (reduced volume). In contrast, non-equilibrium budding remains experimentally widely unexplored, especially when timescales fall well below the characteristic diffusion time of lipids, tau. We show that localized mechanical perturbations, initiated by driving giant unilamellar vesicles (GUVs) through their lipid main phase transition from the gel to the fluid phase, lead to the immediate formation of rapidly growing, localized, non-equilibrium buds when the transition takes place at short timescales (

Assuntos
Lipossomas Unilamelares/química , Simulação de Dinâmica Molecular , Transição de Fase , Temperatura , Fatores de Tempo , Viscosidade
9.
Chemphyschem ; 9(4): 641-5, 2008 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-18306189

RESUMO

A novel method for pumping very small volumes of liquid by using surface acoustic waves is employed to create a microfluidic flow chamber on a chip. It holds a volume of only a few mul and its planar design provides complete architectural freedom. This allows for the reconstruction of even complex flow scenarios (e.g. curvatures, bifurcations and stenosis). Addition of polymer walls to the planar fluidic track enables cell culturing on the chip surface and the investigation of cell-cell adhesion dynamics under flow. We demonstrate the flexibility of the system for application in many areas of microfluidic investigations including blood clotting phenomena under various flow conditions and the investigation of different stages of cell adhesion.


Assuntos
Técnicas Analíticas Microfluídicas/instrumentação , Técnicas Analíticas Microfluídicas/métodos , Adesão Celular , Comunicação Celular , Técnicas de Cultura de Células/métodos , Linhagem Celular Tumoral , Humanos , Tamanho da Partícula , Polímeros/química , Propriedades de Superfície , Células Tumorais Cultivadas
10.
J Oral Maxillofac Surg ; 66(12): 2537-44, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19022134

RESUMO

PURPOSE: This randomized, clinical multicenter trial investigated the treatment outcomes of displaced condylar fractures, and whether radiographic fracture level was a prognostic factor in therapeutic decision-making between open reduction and internal fixation (ORIF) versus closed reduction and mandibulomaxillary fixation (CRMMF). PATIENTS AND METHODS: Sixty-six patients with 79 displaced fractures (deviation of 10 degrees to 45 degrees, or shortening of the ascending ramus >or=2 mm) of the condylar process of the mandible at 7 clinical centers were enrolled. Patients were randomly allocated to CRMMF (n = 30 patients) or ORIF (n = 36 patients) treatment. The following parameters were measured 6 months after the trauma. Clinical parameters included mouth opening, protrusion, and laterotrusion. Radiographic parameters included level of the fracture, deviation of the fragment, and shortening of the ascending ramus. Subjective parameters included pain (according to a visual analogue scale), discomfort, and subjective functional impairment with a mandibular functional impairment questionnaire. RESULTS: The difference in average mouth opening was 12 mm (P or=2 mm, should be treated with ORIF, irrespective of level of the fracture.


Assuntos
Fixação de Fratura/instrumentação , Fixação de Fratura/métodos , Técnicas de Fixação da Arcada Osseodentária/instrumentação , Côndilo Mandibular/lesões , Fraturas Mandibulares/cirurgia , Tomada de Decisões , Fixação Interna de Fraturas/instrumentação , Humanos , Côndilo Mandibular/cirurgia , Fraturas Mandibulares/patologia , Dor Pós-Operatória , Estudos Prospectivos , Amplitude de Movimento Articular , Articulação Temporomandibular/lesões , Resultado do Tratamento
11.
J Craniomaxillofac Surg ; 46(3): 511-520, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29395993

RESUMO

INTRODUCTION: Microvascular surgery following tumor resection has become an important field of oral and maxillofacial surgery (OMFS). Following the results from management of T1/T2 floor-of-mouth and tongue squamous cell carcinoma (SCC) in German-speaking countries, Europe, and worldwide, this paper presents specific concepts for the management of resection and reconstruction of T3/T4 SCC of the maxillary and mandibular alveolar process and tongue. METHODS: The DÖSAK questionnaire was distributed in three different phases to a growing number of maxillofacial units worldwide. Within this survey, clinical patient settings were presented to participants and center-specific treatment strategies were evaluated. RESULTS: A total of 188 OMFS units from 36 different countries documented their treatment strategies for T3/T4 maxillary and mandibular alveolar process and tongue SCC. The extent of surgical resections and subsequent reconstructions is more consistent than with T1/T2 tumors, although the controversy surrounding continuity resections and mandible-sparing procedures remains. For continuity resection of the mandible the fibula free flap is the most frequently used bone replacement, whereas maxilla reconstruction concepts are less consistent, ranging from locoregional coverage concepts and different microvascular reconstruction options to treatment via obturator prosthesis. CONCLUSION: Results from treatment strategies for T3/T4 tumors underline the limited evidence for the appropriate amount of resection and subsequent reconstruction process, especially in cases involving the mandible. Prospective randomized trials will be necessary in the long term to establish valid treatment guidelines.


Assuntos
Processo Alveolar , Neoplasias Maxilomandibulares/cirurgia , Carcinoma de Células Escamosas de Cabeça e Pescoço/cirurgia , Neoplasias da Língua/cirurgia , Idoso , Feminino , Saúde Global , Pesquisas sobre Atenção à Saúde , Humanos , Neoplasias Maxilomandibulares/patologia , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Procedimentos Cirúrgicos Bucais , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Neoplasias da Língua/patologia
12.
J Craniomaxillofac Surg ; 35(3): 151-60, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17583525

RESUMO

AIM: While functionally stable osteosynthesis is a generally accepted method to treat all dislocated fractures of the skull, open reduction and rigid fixation of fractures of the mandibular condyle are still controversial. The risks involved in the surgical approaches and the difficulties during reposition are the main controversies. Improvements made in surgical access and osteosynthesis materials as well as the development of special instruments were the reasons for re-evaluating the surgical results. METHODS: Forty patients with displaced or dislocated fractures of the mandibular condyle were re-examined. In 20 patients (21 fractures) an intraoral approach, in 20 more patients (24 fractures) an extraoral perimandibular approach was applied. The results were compared by means of axiography and radiology as well as clinically with regard to function 6 months postoperatively. RESULTS: While almost all fractures were correctly reduced following application of an extraoral access, reduction was correct in only 50% of the patients treated with an intraoral approach. Re-displacement and complications during osteosynthesis were the reasons. The group of patients treated via the intraoral approach showed less favourable results radiologically, clinically, and as judged by the patients' subjective feelings. Especially axiographical examination of the latter fractures revealed a restricted translation indicating that the fractures had not healed primarily. CONCLUSION: In order to avoid complications, the only fractures which should be treated intraorally are those which allow exact reduction even under the conditions of a limited view and reduced possibilities of surgical manipulation during reduction. This applies in general to fractures of the mandibular condyle with a laterally displaced condyle and a shortened ascending ramus. For all other dislocated or displaced fractures, extraoral reduction and osteosynthesis are the methods of choice.


Assuntos
Fixação Interna de Fraturas/métodos , Côndilo Mandibular/lesões , Fraturas Mandibulares/cirurgia , Adulto , Placas Ósseas , Parafusos Ósseos , Feminino , Fixação Interna de Fraturas/efeitos adversos , Fixação Interna de Fraturas/instrumentação , Fraturas Mal-Unidas/etiologia , Humanos , Registro da Relação Maxilomandibular , Masculino , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/fisiopatologia , Fraturas Mandibulares/diagnóstico por imagem , Fraturas Mandibulares/fisiopatologia , Procedimentos Cirúrgicos Bucais/efeitos adversos , Radiografia , Transtornos da Articulação Temporomandibular/etiologia
13.
J Craniomaxillofac Surg ; 45(4): 547-551, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28223013

RESUMO

One third of adult patients with orthognathic surgery of a prognathic or retrognathic mandible show relapse. The sagittal split osteotomy of the mandible leads to a displacement of both parts up to 10 mm without any changes of muscle attachment. Changed mandible length needs adaptation of muscle capacity because of changed force to moment ratio. The aim of this Microarray study was to analyze the general genetic response of masseter muscle in patients with retrognathism or prognathism of the mandible six months after surgery in comparison with healthy untreated controls. We found in tissue samples from masseter muscle a reduction of different entities between patients and controls but less in retrognathic than in prognathic patients (274/429). The different entities to controls in prognathia were reduced from 1862 to 1749 but increased in retrognathia from 1070 to 1563. We have to consider that the total amount of different entities to the controls is higher in patients with prognathic mandible (7364) because of their strong genetic controlled development compared with that in patients with retrognathic mandible (4126), which is more environmentally influenced. It can be concluded that function follows form after surgical change with high inheritance. In retrognathic patients the adaptation could be delayed or the capacity of regeneration potential is not sufficient.


Assuntos
Músculo Masseter , Análise em Microsséries , Procedimentos Cirúrgicos Ortognáticos , Prognatismo/genética , Prognatismo/cirurgia , Retrognatismo/genética , Retrognatismo/cirurgia , Humanos , Músculo Masseter/crescimento & desenvolvimento
14.
J Craniomaxillofac Surg ; 45(12): 2097-2104, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29033209

RESUMO

INTRODUCTION: Microvascular surgery following tumor resection has become an important field of oral maxillofacial surgery (OMFS). Following the results on general aspects of current reconstructive practice in German-speaking countries, Europe and worldwide, this paper presents specific concepts for the management of resection and reconstruction of T1/T2 squamous cell carcinoma (SCC) of the anterior floor of the mouth and tongue. METHODS: The DOESAK questionnaire was distributed in three different phases to a growing number of maxillofacial units worldwide. Within this survey, clinical patient settings were presented to participants and center-specific treatment strategies were evaluated. RESULTS: A total of 188 OMFS units from 36 different countries documented their treatment strategies for T1/T2 anterior floor of the mouth squamous cell carcinoma and tongue carcinoma. For floor of mouth carcinoma close to the mandible, a wide variety of concepts are presented: subperiosteal removal of the tumor versus continuity resection of the mandible and reconstruction ranging from locoregional closure to microvascular bony reconstruction. For T2 tongue carcinoma, concepts are more uniform. CONCLUSION: These results demonstrate the lack of evidence and the controversy of different guidelines for the extent of safety margins and underline the crucial need of global prospective randomized trials on this topic to finally obtain evidence for a common guideline based on a strong community of OMFS units.


Assuntos
Carcinoma de Células Escamosas/patologia , Carcinoma de Células Escamosas/cirurgia , Neoplasias de Cabeça e Pescoço/patologia , Neoplasias de Cabeça e Pescoço/cirurgia , Soalho Bucal , Neoplasias Bucais/patologia , Neoplasias Bucais/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Neoplasias da Língua/patologia , Neoplasias da Língua/cirurgia , Saúde Global , Humanos , Estadiamento de Neoplasias , Carcinoma de Células Escamosas de Cabeça e Pescoço
15.
J Craniomaxillofac Surg ; 34 Suppl 2: 110-5, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17071403

RESUMO

INTRODUCTION: Surgical correction of malocclusion changes the force to moment ratio of masticatory muscles inserting at the mandible caused by shortening, lengthening and rotation of the bone following osteotomy. During muscle adaptation the expression of mRNA for the myosin heavy chain (MyHC) of type I and type II fibres may be changed. MATERIAL AND METHODS: The adaptation of the masseter muscle was investigated at the mRNA level in 10 patients 6 months after orthognathic surgery in the mandible. The competitive polymerase chain reaction (cPCR) is a suitable method for quantification of MyHC mRNA. For application of this minimal invasive method an amount of 35 mg muscle tissue was sufficient. RESULTS: 6 month postoperatively there was a deficiency of about 87% of MyHC mRNA for fibre type I and II in both groups of patients. The deficiency in patients with mesial position of the mandible was higher but not significant different to patients with distal malocclusion. CONCLUSION: Patients should use the postoperative interval for training their masticatory muscles. This improves the stability of treatment result and prevents relapse.


Assuntos
Mandíbula/cirurgia , Músculo Masseter/química , Cadeias Pesadas de Miosina/análise , Osteotomia/efeitos adversos , RNA Mensageiro/análise , Adulto , Cefalometria , Feminino , Humanos , Masculino , Má Oclusão/cirurgia , Mandíbula/diagnóstico por imagem , Maxila/diagnóstico por imagem , Cadeias Pesadas de Miosina/genética , Radiografia
16.
J Craniomaxillofac Surg ; 34(5): 306-14, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16781159

RESUMO

AIM: The aim of this international prospective randomized multi-centre study was to compare operative and conservative treatment of displaced condylar fractures of the mandible. METHODS AND PATIENTS: Out of a total of 88 randomized patients from 7 centres, 66 patients with 79 fractures of the mandibular condylar process completed the study and were evaluated. All fractures were displaced, being either angulated between 10 degrees and 45 degrees or the ascending ramus was shortened by more than 2mm. The follow-up examinations 6 weeks and 6 months following treatment included evaluation of radiographic measurements, clinical, functional and subjective parameters including visual analogue scale for pain and the Mandibular Function Impairment Questionnaire index for dysfunction. RESULTS: Correct anatomical position of the fragments was achieved significantly more often in the operative group in contrast to the closed treatment group. Regarding mouth opening/lateral excursion/protrusion, significant (p=0.01) differences were observed between both groups (open 47/16/7mm versus closed 41/13/5mm). The visual analogue scoring revealed significant (p=0.03) differences with less pain in the operative treatment group (2.9 open versus 13.5 closed). The Mandibular Function Impairment Questionnaire index recorded a significant (p=0.001) difference with less pain and discomfort in the open treatment group (10.5 versus 2.4 points). CONCLUSION: Both treatment options for condylar fractures of the mandible yielded acceptable results. However, operative treatment, irrespective of the method of internal fixation used, was superior in all objective and subjective functional parameters.


Assuntos
Côndilo Mandibular/lesões , Fraturas Mandibulares/terapia , Adulto , Feminino , Humanos , Masculino , Côndilo Mandibular/diagnóstico por imagem , Côndilo Mandibular/cirurgia , Fraturas Mandibulares/diagnóstico por imagem , Fraturas Mandibulares/cirurgia , Medição da Dor , Estudos Prospectivos , Radiografia , Inquéritos e Questionários , Resultado do Tratamento
17.
Sci Rep ; 6: 22874, 2016 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-27216038

RESUMO

Local changes in pH are known to significantly alter the state and activity of proteins and enzymes. pH variations induced by pulses propagating along soft interfaces (e.g. membranes) would therefore constitute an important pillar towards a physical mechanism of biological signaling. Here we investigate the pH-induced physical perturbation of a lipid interface and the physicochemical nature of the subsequent acoustic propagation. Pulses are stimulated by local acidification and propagate - in analogy to sound - at velocities controlled by the interface's compressibility. With transient local pH changes of 0.6 directly observed at the interface and velocities up to 1.4 m/s this represents hitherto the fastest protonic communication observed. Furthermore simultaneously propagating mechanical and electrical changes in the lipid interface are detected, exposing the thermodynamic nature of these pulses. Finally, these pulses are excitable only beyond a threshold for protonation, determined by the pKa of the lipid head groups. This protonation-transition plus the existence of an enzymatic pH-optimum offer a physical basis for intra- and intercellular signaling via sound waves at interfaces, where not molecular structure and mechano-enyzmatic couplings, but interface thermodynamics and thermodynamic transitions are the origin of the observations.


Assuntos
Lipídeos/química , Lipossomas Unilamelares/química , Acústica , Concentração de Íons de Hidrogênio , Prótons , Transdução de Sinais , Eletricidade Estática , Termodinâmica , Unitiol/química
18.
Sci Rep ; 6: 22849, 2016 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-26955791

RESUMO

The implant-bone interface is the scene of competition between microorganisms and distinct types of tissue cells. In the past, various strategies have been followed to support bony integration and to prevent bacterial implant-associated infections. In the present study we investigated the biological properties of diamond-like carbon (DLC) surfaces containing silver nanoparticles. DLC is a promising material for the modification of medical implants providing high mechanical and chemical stability and a high degree of biocompatibility. DLC surface modifications with varying silver concentrations were generated on medical-grade titanium discs, using plasma immersion ion implantation-induced densification of silver nanoparticle-containing polyvinylpyrrolidone polymer solutions. Immersion of implants in aqueous liquids resulted in a rapid silver release reducing the growth of surface-bound and planktonic Staphylococcus aureus and Staphylococcus epidermidis. Due to the fast and transient release of silver ions from the modified implants, the surfaces became biocompatible, ensuring growth of mammalian cells. Human endothelial cells retained their cellular differentiation as indicated by the intracellular formation of Weibel-Palade bodies and a high responsiveness towards histamine. Our findings indicate that the integration of silver nanoparticles into DLC prevents bacterial colonization due to a fast initial release of silver ions, facilitating the growth of silver susceptible mammalian cells subsequently.


Assuntos
Antibacterianos/farmacologia , Materiais Biocompatíveis/química , Diamante/química , Nanopartículas/química , Próteses e Implantes , Prata/farmacologia , Antibacterianos/toxicidade , Diferenciação Celular/efeitos dos fármacos , Células Endoteliais/fisiologia , Humanos , Prata/toxicidade , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus epidermidis/efeitos dos fármacos , Staphylococcus epidermidis/crescimento & desenvolvimento , Propriedades de Superfície
19.
J Appl Genet ; 46(2): 227-36, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-15876691

RESUMO

The aim of this study was to determine the amount of myosin heavy chain (MyHC) proteins and MyHC mRNA in muscles of patients with different positions of the mandible. Ten adult patients for orthognathic surgery were divided into two groups: distal and mesial malocclusion. The mRNA expression of two MyHC isoforms of the anterior and posterior part of the right and left side of the human masseter muscle was analysed with a competitive RT-PCR assay. An exogenous template that includes oligonucleotide sequences specific for sarcomeric MyHC isoforms (1 and 2x) was constructed and utilized as competitor. Different isoforms of the MyHC protein were identified by Western blot analysis. In the total mRNA pool of the masseter muscle, the MyHC 1 mRNA level was 25.5 +/- 7.6% and the MyHC 2x mRNA was 2.5 +/- 1.2%. The anterior part of the masseter muscle from patients with distal occlusion contained more type 1 and 2x MyHC mRNA, as compared to patients with mesial occlusion (P < 0.05). No difference in the protein distribution was observed. The differences in mRNA expression may be caused by the enforced stress of the masticatory muscle in distal occlusion because of the disadvantageous pivot.


Assuntos
Regulação da Expressão Gênica , Má Oclusão/genética , Músculo Masseter/patologia , Cadeias Pesadas de Miosina/biossíntese , Cadeias Pesadas de Miosina/genética , Adulto , Fenômenos Biomecânicos , Western Blotting , Feminino , Humanos , Masculino , RNA Mensageiro/biossíntese , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Estresse Mecânico
20.
J Craniomaxillofac Surg ; 33(1): 8-12, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15694143

RESUMO

AIM: To simulate the surgery of dysgnathia, several forms of computer software allowing two-dimensional 'virtual' planning are frequently used. However, in many cases it is not possible to transfer the virtual plan accurately to the surgical site. It is the purpose of this study to find the errors likely to occur when transferring the data. METHODS: In 22 bimaxillary osteotomies for dysgnathia, the results of preoperative planning were compared with the surgical outcomes. The programme WinCeph 4.19 (Compudent) was used for cephalometric analyses and simulation of the operations. RESULTS: Six major skeletal parameters were evaluated when comparing both the planned and the actual outcome, and the following results were recorded: Delta-SNA 1.53 degrees (+/-1.20), Delta-SNB 1.67 degrees (+/-1.29), Delta-ANB 1.62 degrees (+/-1.47), Delta-NL-NSL 3.9 degrees (+/-2.30), Delta-ML-NSL 3.6 degrees (+/-3.7) and Delta-ArGoMe 6.1 degrees (+/-4.6). CONCLUSION: It was anticipated that the most important differences between planned and surgical outcomes were found to be in the vertical changes. Planning and data transfer was comparatively accurate with regard to sagittal data. Apart from several mechanical methods for data transfer, systems using navigation are therefore being discussed and used increasingly. They ensure accurate data transfer to the surgical site.


Assuntos
Cefalometria/métodos , Maxila/cirurgia , Osteotomia de Le Fort/métodos , Cirurgia Assistida por Computador/métodos , Humanos , Maxila/anormalidades , Maxila/diagnóstico por imagem , Radiografia
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