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PURPOSE: This study aimed to investigate the length change patterns of the native deep medial collateral ligament (dMCL) and potential anteromedial reconstructions (AMs) that might be added to a reconstruction of the superficial MCL (sMCL) to better understand the control of anteromedial rotatory instability (AMRI). METHODS: Insertion points of the dMCL and potential AM reconstructions were marked with pins (tibial) and eyelets (femoral) in 11 cadaveric knee specimens. Length changes between the pins and eyelets were then tested using threads in a validated kinematics rig with muscle loading of the quadriceps and iliotibial tract. Between 0° and 100° knee flexion, length change pattern of the anterior, middle and posterior part of the dMCL and simulated AM reconstructions were analysed using a rotary encoder. Isometry was tested using the total strain range (TSR). RESULTS: The tibiofemoral distance of the anterior dMCL part lengthened with flexion (+12.7% at 100°), whereas the posterior part slackened with flexion (-12.9% at 100°). The middle part behaved almost isometrically (maximum length: +2.8% at 100°). Depending on the femoral position within the sMCL footprint, AM reconstructions resulted in an increase in length as the knee flexed when a more centred position was used, irrespective of the tibial attachment position. Femoral positioning in the posterior aspect of the sMCL footprint exhibited <4% length change and was slightly less tight in flexion (min TSR = 3.6 ± 1.5%), irrespective of the tibial attachment position. CONCLUSION: The length change behaviour of potential AM reconstructions in a functionally intact knee is mainly influenced by the position of the femoral attachment, with different tibial attachments having a minimal effect on length change. Surgeons performing AM reconstructions to control AMRI would be advised to choose a femoral graft position in the posterior part of the native sMCL attachment to optimise graft length change behaviour. Given the high frequency of MCL injuries, sufficient restoration of AMRI is essential in isolated and combined ligamentous knee injuries. LEVEL OF EVIDENCE: There is no level of evidence as this study was an experimental laboratory study.
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Ligamentos Colaterais , Traumatismos do Joelho , Humanos , Articulação do Joelho/cirurgia , Articulação do Joelho/fisiologia , Fêmur/cirurgia , Tíbia/cirurgia , Fenômenos Biomecânicos , Amplitude de Movimento Articular/fisiologia , CadáverRESUMO
BACKGROUND: In Germany, nosocomial infections and postoperative wound infections are a significant burden for the healthcare system and the patients affected. A postoperative wound infection is often accompanied by a massive deterioration in the quality of the treatment success of surgical measures in terms of patient stress, the functional results and the cost-effectiveness of a treatment for the service provider. The aim of this article is to present the current hygiene requirements for the perioperative setting in a comprehensible manner and to explain them to everyone involved in the surgical procedure. METHOD: First of all, the importance of hygienic measures is explained, as well as a brief overview of the development up to modern hygiene concepts of today. Then the current recommendations of the KRINKO (Commission for Hospital Hygiene and Infection Prevention at the Robert Koch Institute): "Prevention of postoperative wound infections, recommendation of the Commission for Hospital Hygiene and Infection Prevention (KRINKO) at the Robert Koch Institute" are presented. CONCLUSION: Hygienic work is a basic prerequisite for work in the surgical area, because convincing treatment results with good functional results cannot be achieved in many areas (e.g. modern endoprosthetics) without sufficient hygiene. The modern requirements for hygienic work are complex and affect all areas of the hospital. The best possible degree of process quality can only be guaranteed if all pillars of modern hygiene concepts are observed.
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Infecção Hospitalar , Salas Cirúrgicas , Humanos , Infecção da Ferida Cirúrgica/prevenção & controle , Higiene , Infecção Hospitalar/prevenção & controle , AlemanhaRESUMO
BACKGROUND: Crossfit athletes consistently recruit or transfer high levels of repetitive forces through the spine, and MRI has documented a higher rate of intervertebral disc degeneration in athletes compared with matched controls. The aim of this study was to evaluate early degenerative spinal disc changes in elite female CrossFit athletes quantified by 3.0 Tesla magnetic resonance imaging (MRI) matched with female none-athletes. METHODS: In a cross-sectional single-center study 19 asymptomatic adult participants, nine German female elite Crossfit athletes and ten female participants underwent spinal MRI (3.0T). Demographic data, spinal clinical examination results and sport-specific performance parameters were collected prior to the MRI. The primary outcome was the prevalence of degenerative spinal disc changes. The secondary outcome was the grade of degeneration using Pfirrmann grading. RESULTS: A total of 437 discs underwent spinal MRI (3.0T). The prevalence of early degenerative disc disease was not increased. Pfirrmann degenerative grade did not show significant differences among groups. CONCLUSION: Asymptomatic female elite Crossfit athletes do not show an increased prevalence of degenerative disc disease. Compared to a sex-matched control group, high training volume in Crossfit does not correlate to a higher incidence of degenerative disc changes in young females.
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Degeneração do Disco Intervertebral , Disco Intervertebral , Adulto , Humanos , Feminino , Degeneração do Disco Intervertebral/diagnóstico por imagem , Degeneração do Disco Intervertebral/epidemiologia , Estudos Transversais , Prevalência , Vértebras Lombares/patologia , Disco Intervertebral/patologia , Imageamento por Ressonância Magnética/métodos , AtletasRESUMO
Critical-sized bone defects resulting from trauma, inflammation, and tumor resections are individual in their size and shape. Implants for the treatment of such defects have to consider biomechanical and biomedical factors, as well as the individual conditions within the implantation site. In this context, 3D printing technologies offer new possibilities to design and produce patient-specific implants reflecting the outer shape and internal structure of the replaced bone tissue. The selection or modification of materials used in 3D printing enables the adaption of the implant, by enhancing the osteoinductive or biomechanical properties. In this study, scaffolds with bone spongiosa-inspired structure for extrusion-based 3D printing were generated. The computer aided design process resulted in an up scaled and simplified version of the bone spongiosa. To enhance the osteoinductive properties of the 3D printed construct, polycaprolactone (PCL) was combined with 20% (wt) calcium phosphate nano powder (CaP). The implants were designed in form of a ring structure and revealed an irregular and interconnected porous structure with a calculated porosity of 35.2% and a compression strength within the range of the natural cancellous bone. The implants were assessed in terms of biocompatibility and osteoinductivity using the osteosarcoma cell line MG63 and patient-derived mesenchymal stem cells in selected experiments. Cell growth and differentiation over 14 days were monitored using confocal laser scanning microscopy, scanning electron microscopy, deoxyribonucleic acid (DNA) quantification, gene expression analysis, and quantitative assessment of calcification. MG63 cells and human mesenchymal stem cells (hMSC) adhered to the printed implants and revealed a typical elongated morphology as indicated by microscopy. Using DNA quantification, no differences for PCL or PCL-CaP in the initial adhesion of MG63 cells were observed, while the PCL-based scaffolds favored cell proliferation in the early phases of culture up to 7 days. In contrast, on PCL-CaP, cell proliferation for MG63 cells was not evident, while data from PCR and the levels of calcification, or alkaline phosphatase activity, indicated osteogenic differentiation within the PCL-CaP constructs over time. For hMSC, the highest levels in the total calcium content were observed for the PCL-CaP constructs, thus underlining the osteoinductive properties.
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The anterior ilioinguinal and the posterior Kocher-Langenbeck approach have long been the standard surgical approaches to the acetabulum. The last decade has witnessed the development of so-called intrapelvic approaches for anterior pathologies because they provide better exposure of the quadrilateral plate. Currently, the modified Stoppa approach and the pararectus approach are frequently used by surgeons for the treatment of acetabular fractures. We investigated an even more direct access to the entire anterior column and the quadrilateral plate via the abdominal wall muscles, between the incisions for the ilioinguinal and the pararectus approach.After intensive study of anatomic specimens, a cadaver dissection was performed prior to clinical application. The approach was then used in 20 patients who were assessed retrospectively.Postoperative CT scans showed that, according to the Matta scoring system, the quality of fracture reduction was "anatomical" (≤ 1 mm) in 12 (60%), "imperfect" (2-3 mm) in four (20%), and "poor" (> 3 mm) in four (20%) patients. Numerous minor complications were observed; the majority of these had resolved at the time of discharge.In conclusion, the anterior transmuscular intrapelvic approach (ATI) is a safe and effective alternative to the ilioinguinal and pararectal approaches, and may be regarded as an evolutionary advancement of traditional procedures.
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Fraturas Ósseas , Fraturas do Quadril , Lesões do Pescoço , Fraturas da Coluna Vertebral , Humanos , Fraturas Ósseas/diagnóstico por imagem , Fraturas Ósseas/cirurgia , Fixação Interna de Fraturas/métodos , Estudos Retrospectivos , Acetábulo/diagnóstico por imagem , Acetábulo/cirurgia , Acetábulo/lesões , Resultado do TratamentoRESUMO
The endothelial cell lining creates an interface between circulating blood and adjoining tissue and forms one of the most critical barriers and targets for therapeutical intervention. Recent studies suggest that fucoidans, sulfated and fucose-rich polysaccharides from brown seaweed, show multiple promising biological effects, including anti-inflammatory properties. However, their biological activity is determined by chemical characteristics such as molecular weight, sulfation degree, and molecular structure, which vary depending on the source, species, and harvesting and isolation method. In this study, we investigated the impact of high molecular weight (HMW) fucoidan extract on endothelial cell activation and interaction with primary monocytes (MNCs) in lipopolysaccharide (LPS)-induced inflammation. Gentle enzyme-assisted extraction combined with fractionation by ion exchange chromatography resulted in well-defined and pure fucoidan fractions. FE_F3, with a molecular weight ranging from 110 to 800 kDa and a sulfate content of 39%, was chosen for further investigation of its anti-inflammatory potential. We observed that along with higher purity of fucoidan fractions, the inflammatory response in endothelial mono- and co-cultures with MNCs was reduced in a dose-dependent manner when testing two different concentrations. This was demonstrated by a decrease in IL-6 and ICAM-1 on gene and protein levels and a reduced gene expression of TLR-4, GSK3ß and NF-kB. Expression of selectins and, consequently, the adhesion of monocytes to the endothelial monolayer was reduced after fucoidan treatment. These data indicate that the anti-inflammatory effect of fucoidans increases with their purity and suggest that fucoidans might be useful in limiting the inflammatory response of endothelial cells in cases of LPS-induced bacterial infection.
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Células Endoteliais , Lipopolissacarídeos , Lipopolissacarídeos/farmacologia , Peso Molecular , Polissacarídeos/química , Anti-Inflamatórios , LeucócitosRESUMO
Low serum levels of 1α, 25-dihydroxyvitamin D3 (VD3) are associated with a higher mortality in trauma patients with sepsis or ARDS. However, the molecular mechanisms behind this observation are not yet understood. VD3 is known to stimulate lung maturity, alveolar type II cell differentiation, or pulmonary surfactant synthesis and guides epithelial defense during infection. In this study, we investigated the impact of VD3 on the alveolar-capillary barrier in a co-culture model of alveolar epithelial cells and microvascular endothelial cells respectively in the individual cell types. After stimulation with bacterial LPS (lipopolysaccharide), gene expression of inflammatory cytokines, surfactant proteins, transport proteins, antimicrobial peptide, and doublecortin-like kinase 1 (DCLK1) were analyzed by real-time PCR, while corresponding proteins were evaluated by ELISA, immune-fluorescence, or Western blot. The effect of VD3 on the intracellular protein composition in H441 cells was analyzed by quantitative liquid chromatography-mass spectrometry-based proteomics. VD3 effectively protected the alveolar-capillary barrier against LPS treatment, as indicated by TEER measurement and morphological assessment. VD3 did not inhibit the IL-6 secretion by H441 and OEC but restricted the diffusion of IL-6 to the epithelial compartment. Further, VD3 could significantly suppress the surfactant protein A expression induced in the co-culture system by LPS treatment. VD3 induced high levels of the antimicrobial peptide LL-37, which counteracted effects by LPS and strengthened the barrier. Quantitative proteomics identified VD3-dependent protein abundance changes ranging from constitutional extracellular matrix components and surfactant-associated proteins to immune-regulatory molecules. DCLK1, as a newly described target molecule for VD3, was prominently stimulated by VD3 (10 nM) and seems to influence the alveolar-epithelial cell barrier and regeneration.
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Células Endoteliais , Interleucina-6 , Humanos , Lipopolissacarídeos/farmacologia , Proteínas Associadas a Surfactantes Pulmonares , Células Epiteliais Alveolares , Tensoativos , Quinases Semelhantes a DuplacortinaRESUMO
Multiple trauma patients with severe chest trauma are at increased risk for tracheostomy. While the risk factors associated with the need for tracheostomy are well established in the general critical care population, they have not yet been validated in a cohort of patients suffering severe thoracic trauma. This retrospective cohort study analysed data on patients aged 18 years or older who were admitted to one of the six participating academic level I trauma centres with multiple injuries, including severe thoracic trauma (AISThorax ≥ 3) between 2010 and 2014. A multivariable binary regression was used to identify predictor variables for tracheostomy and to develop the Tracheostomy in Thoracic Trauma Prediction Score (T3P-Score). The study included 1019 adult thoracic trauma patients, of whom 165 underwent tracheostomy during their intensive care unit (ICU) stay. Prehospital endotracheal intubation (adjusted OR [AOR]: 2.494, 95% CI [1.412; 4.405]), diagnosis of pneumonia during the ICU stay (AOR: 4.374, 95% CI [2.503; 7.642]), duration of mechanical ventilation (AOR: 1.008/hours of intubation, 95% CI [1.006; 1.009]), and an AISHead ≥ 3 (AOR 1.840, 95% CI [1.039; 3.261]) were independent risk factors for tracheostomy. Patients with sepsis had a lower risk of tracheostomy than patients without sepsis (AOR 0.486, 95% CI [0.253; 0.935]). The T3P-Score had high predictive validity for tracheostomy (ROCAUC = 0.938, 95% CI [0.920, 0.956]; Nagelkerke's R2 was 0.601). The T3P-Score's specificity was 0.68, and the sensitivity was 0.96. The severity of thoracic trauma did not predict the need for tracheostomy. Follow-up studies should validate the T3P-Score in external data sets and study the reasons for the reluctant use of tracheostomy in patients with severe thoracic trauma and subsequent sepsis.Trial registration: The study was applied for and registered a priori with the respective ethics committees.
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Traumatismo Múltiplo , Sepse , Traumatismos Torácicos , Adulto , Humanos , Traqueostomia , Estudos Retrospectivos , Traumatismos Torácicos/complicações , Traumatismo Múltiplo/complicações , Sepse/complicaçõesRESUMO
Robot-assisted surgery offers many advantages with respect to precision and facilitation in medicine, whereby the physician controls the system externally by guiding the movement of the robot during the operation. Despite training and experience, operating errors by the user cannot be excluded. In addition, for the established systems the precise guidance of instruments along complexly shaped surfaces, e.g. for milling or cutting, depends on the skills of the operator. This article presents an expansion of the established robotic assistance for smooth movement along randomly shaped surfaces and introduces a movement automation which goes beyond the assistance systems used so far. Both approaches aim to improve the accuracy in surface-dependent medical procedures and avoid operator errors. Special applications with these requirements are, for example the execution of precise incisions or removal of adhering tissue in cases of spinal stenosis. A segmented computed tomography (CT) or magnetic resonance imaging (MRI) scan serves as the basis for a precise implementation. For robotic assistance externally guided by the operator the commands given to the robot are tested and monitored without delay so that adaptation of the movement exactly corresponding to the surface can be carried out. In contrast, the automation for the established systems differs in that the movement along the desired surface is roughly planned by the surgeon preoperatively by marking prominent points on the CT or MRI scan. From this a suitable track, including the appropriate instrument orientation, is calculated and, after checking the results, the robot finally carries this out autonomously. Based on this procedure, which is planned by humans and carried out by robots, errors are minimized, respective advantages are maximized and costly training on correct steering of robots becomes obsolete. The evaluation is carried out both in simulation and also experimentally on a complexly shaped 3D-printed lumbar vertebra from a CT scan with a Stäubli TX2-60 manipulator (Stäubli Tec-Systems GmbH Robotics, Bayreuth, Germany); however, the procedures are also transferable to and applicable on every other robotic system that covers the necessary working space, such as the da Vinci system.
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Procedimentos Ortopédicos , Ortopedia , Procedimentos Cirúrgicos Robóticos , Robótica , Humanos , Robótica/métodos , Procedimentos Cirúrgicos Robóticos/métodos , AlemanhaRESUMO
Camera-based navigation in the hybrid operating room represents a possibility for precise, low-complication and efficient pedicle screw insertion in spinal surgery. In addition to increasing patient safety, the use of camera-based navigation as an orientation aid for the surgeon reduces radiation exposure. Camera-based navigation focuses on the surgeon's anatomical knowledge of landmarks, preoperative image acquisition, and subsequent information integration by the navigation software. The information provided from volume tomography (cone beam computed tomography, CBCT) and surface referencing through the video input from four optical cameras and the associated surface markers is collected, processed, optimized and customized by the software used. The result is the creation of a trajectory that allows the surgeon to analyze and evaluate complex anatomical structures more easily and facilitates the performance of the planned procedure. Minimally invasive insertion of pedicle screws using surface-reference navigation (augmented reality surgical navigation; ARSN) provides comparable accuracy to conventional fluoroscopic insertion of pedicle screws while reducing radiation by eliminating the need for postoperative computed tomographic imaging.
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Realidade Aumentada , Salas Cirúrgicas , Humanos , Vértebras Lombares/cirurgia , Parafusos Pediculares , Cirurgia Assistida por Computador/métodosRESUMO
BACKGROUND: The purpose of the study was to investigate and describe neurovascular complications and mid-term clinical outcomes of operatively managed fractures of the distal humerus in a paediatric population. Neurovascular injuries are common in these fractures, but reports about their implications for mid-term clinical outcomes is sparse. METHODS: A single-centre retrospective study was conducted at a university teaching hospital investigating paediatric patients who underwent operative management of a distal humerus fracture between 2014 and 2018. Patient demographics, fracture classification, pre-, peri- and postoperative neurovascular complications were investigated. Mid-term follow up clinical examination and functional scoring using QuickDASH, the Broberg and Morrey Score (BMS), the Mayo Elbow Performance Score (MEPS) and the Numeric Rating Scale were performed. RESULTS: A total of 84 patients were identified, of which 34 met the inclusion criteria and were available for follow-up clinical examination. The average time to follow-up was 150 weeks (1049.44 days ± 448.54). Ten primary traumatic neurovascular complications were identified, the majority of which involved the median nerve. Primary traumatic dissection of the brachial artery was recorded in three patients. Secondary iatrogenic nerve injury was documented in five patients after previously normal clinical examination. At follow-up, the average QuickDASH score was 3.0 ± 4.3, BMS was 98.6 ± 3.4 and MEPS was 97.1 ± 3.3 points. CONCLUSIONS: The mid-term clinical outcome following surgical management of distal humerus fractures is excellent. There is, however, a considerable frequency of both primary and secondary neurovascular complications, which must be considered when opting to treat these injuries surgically.
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STUDY DESIGN: Prospective multi-center study. OBJECTIVE: The study aimed to evaluate the accuracy of pedicle screw placement using a skin marker-based optical surgical navigation system for minimal invasive thoraco-lumbar-sacral pedicle screw placement. METHODS: The study was performed in a hybrid Operating Room with a video camera-based navigation system integrated in the imaging hardware. The patient was tracked with non-invasive skin markers while the instrument tracking was via an on-shaft optical marker pattern. The screw placement accuracy assessment was performed by three independent reviewers, using the Gertzbein grading. The screw placement time as well as the staff and patient radiation doses was also measured. RESULTS: In total, 211 screws in 39 patients were analyzed for screw placement accuracy. Of these 32.7% were in the thoracic region, 59.7% were in the lumbar region, and 7.6% were in the sacral region. An overall accuracy of 98.1% was achieved. No screws were deemed severely misplaced (Gertzbein grading 3). The average time for screw placement was 6 min and 25 secs (± 3 min 33 secs). The average operator radiation dose per subject was 40.3 µSv. The mean patient effective dose (ED) was 11.94 mSv. CONCLUSION: Skin marker-based ON can be used to achieve very accurate thoracolumbarsacral pedicle screw placements.
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Parafusos Pediculares , Fusão Vertebral , Cirurgia Assistida por Computador , Humanos , Estudos Prospectivos , Região Sacrococcígea , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Imageamento Tridimensional/métodos , Cirurgia Assistida por Computador/métodos , Fusão Vertebral/métodosRESUMO
Fucoidans, sulfated polysaccharides from brown algae, possess multiple bioactivities in regard to osteogenesis, angiogenesis, and inflammation, all representing key molecular processes for successful bone regeneration. To utilize fucoidans in regenerative medicine, a delivery system is needed which temporarily immobilizes the polysaccharide at the injured site. Hydrogels have become increasingly interesting biomaterials for the support of bone regeneration. Their structural resemblance with the extracellular matrix, their flexible shape, and capacity to deliver bioactive compounds or stem cells into the affected tissue make them promising materials for the support of healing processes. Especially injectable hydrogels stand out due to their minimal invasive application. In the current study, we developed an injectable thermosensitive hydrogel for the delivery of fucoidan based on chitosan, collagen, and ß-glycerophosphate (ß-GP). Physicochemical parameters such as gelation time, gelation temperature, swelling capacity, pH, and internal microstructure were studied. Further, human bone-derived mesenchymal stem cells (MSC) and human outgrowth endothelial cells (OEC) were cultured on top (2D) or inside the hydrogels (3D) to assess the biocompatibility. We found that the sol-gel transition occurred after approximately 1 min at 37 °C. Fucoidan integration into the hydrogel had no or only a minor impact on the mentioned physicochemical parameters compared to hydrogels which did not contain fucoidan. Release assays showed that 60% and 80% of the fucoidan was released from the hydrogel after two and six days, respectively. The hydrogel was biocompatible with MSC and OEC with a limitation for OEC encapsulation. This study demonstrates the potential of thermosensitive chitosan-collagen hydrogels as a delivery system for fucoidan and MSC for the use in regenerative medicine.
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Quitosana , Hidrogéis , Quitosana/química , Colágeno/química , Células Endoteliais , Humanos , Hidrogéis/química , PolissacarídeosRESUMO
Fucoidans are polysaccharides from brown macroalgae, showing multiple bioactivities important for bone regeneration and bone health. However, the use of fucoidans in medical applications remains sparse due to the heterogeneity in their chemical properties and unclear structure-function relationships. Innovations in extraction techniques and post processing steps are needed to produce homogeneous fucoidan molecules with tailorable bioactivities. Here, we applied enzyme-assisted extraction coupled with enzymatic hydrolysis by Fhf1 fucoidanase to generate low (LMW) and medium molecular weight (MMW) fucoidans from Fucus evanescens. In contrast to the anti-angiogenic properties of the high molecular weight fucoidan, LMW and MMW no longer suppressed the production of pro-angiogenic molecules by bone stem cells, nor impaired the formation of prevascular structures in vitro. In contrast to LMW, a pro-inflammatory response of OEC was observed after treatment with high concentrations of MMW. Thus, fucoidanase hydrolysis could be a useful tool to tailor the bioactivity of fucoidans.
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Fucus , Polissacarídeos , Regeneração Óssea , Fucus/química , Hidrolases , Polissacarídeos/química , Polissacarídeos/farmacologiaRESUMO
Graphene oxide (GO) is a promising material for bone tissue engineering, but the validation of its molecular biological effects, especially in the context of clinically applied materials, is still limited. In this study, we compare the effects of graphene oxide framework structures (F-GO) and reduced graphene oxide-based framework structures (F-rGO) as scaffold material with a special focus on vascularization associated processes and mechanisms in the bone. Highly porous networks of zinc oxide tetrapods serving as sacrificial templates were used to create F-GO and F-rGO with porosities >99% consisting of hollow interconnected microtubes. Framework materials were seeded with human mesenchymal stem cells (MSC), and the cell response was evaluated by confocal laser scanning microscopy (CLSM), deoxyribonucleic acid (DNA) quantification, real-time polymerase chain reaction (RT-PCR), enzyme-linked immunosorbent assay (ELISA), and alkaline phosphatase activity (ALP) to define their impact on cellular adhesion, osteogenic differentiation, and secretion of vascular growth factors. F-GO based scaffolds improved adhesion and growth of MSC as indicated by CLSM and DNA quantification. Further, F-GO showed a better vascular endothelial growth factor (VEGF) binding capacity and improved cell growth as well as the formation of microvascular capillary-like structures in co-cultures with outgrowth endothelial cells (OEC). These results clearly favored non-reduced graphene oxide in the form of F-GO for bone regeneration applications. To study GO in the context of a clinically used implant material, we coated a commercially available xenograft (Bio-Oss® block) with GO and compared the growth of MSC in monoculture and in coculture with OEC to the native scaffold. We observed a significantly improved growth of MSC and formation of prevascular structures on coated Bio-Oss®, again associated with a higher VEGF binding capacity. We conclude that graphene oxide coating of this clinically used, but highly debiologized bone graft improves MSC cell adhesion and vascularization.
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Grafite , Células-Tronco Mesenquimais , Adesão Celular , Diferenciação Celular , DNA/metabolismo , Células Endoteliais , Grafite/química , Humanos , Células-Tronco Mesenquimais/metabolismo , Osteogênese , Engenharia Tecidual/métodos , Alicerces Teciduais/química , Fator A de Crescimento do Endotélio Vascular/metabolismoRESUMO
BACKGROUND: Many falls in older people occur at home, and home hazards (HOHA) are often involved. Fear of falling (FOF) is a frequent and serious consequence of falls. This study aimed to analyze the effectiveness of an autonomous reduction of HOHA on FOF. METHODS: In this single-blinded, prospective cohort study design, the inclusion criteria were female sex, age ≥60 years, no known dementia, community-dwelling, and written informed consent. Using a 54-item room-by-room checklist, the participants identified and autonomously reduced as many HOHA as possible, within 14 days. The FOF was measured using a dichotomous scale (D-FOF) and the Falls Efficacy Scale International (FES-I). Logistic regression models were used to identify the predictors of a substantial reduction of HOHA (≥50%) and FOF (≥25%). RESULTS: A total of 782 women fulfilled the inclusion criteria, and 431 (60.5%) returned the complete checklist on time. The mean age was 72.5 [SD 7.1] years. 43.8% of participants reduced ≥50% of the HOHA. The D-FOF (odds ratio 22.4 [95% confidence interval 11.0-45.3]), age ≥ 75 years (14.1 [7.5-26.4]), polypharmacy (3.0 [1.4-6.5]), and assumed improvability of housing conditions (2.4 [1.3-4.3]) were identified as predictors for substantially reducing HOHA with an area under the curve of 0.91. The initial FES-I score decreased from 24.5 to 19.5. Prior to the intervention, 53.1% showed a high FOF (>22 FES-I scores). Of these, 70.7% participants reduced their high FOF to low FOF. 29.2% of all participants reduced FOF ≥25% postinterventionally, associated with a substantial reduction in HOHA (3.5 [2.2-5.7]) as the strongest independent factor in the multiple logistic regression analysis. CONCLUSION: The use of a self-administered checklist led to a substantial reduction of HOHA and subsequently to a clinically relevant reduction of FOF in older community-dwelling women. Autonomous competence of older people should be considered when developing fall prevention strategies.
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Acidentes por Quedas , Vida Independente , Acidentes por Quedas/prevenção & controle , Idoso , Medo , Feminino , Humanos , Masculino , Razão de Chances , Estudos ProspectivosRESUMO
OBJECTIVES: To compare intraoperative 3D fluoroscopy with a ceiling-mounted flat panel detector in plate osteosynthesis of distal radius fractures (AO/OTA 2R3C1.2) with volar locking plate systems to conventional 2D fluoroscopy for detection of insufficient fracture reduction, plate misplacement and protruding screws. METHODS: Using a common volar approach on 12 cadaver forearms, total intraarticular distal radius fractures were induced, manually reduced and internally fixated with a 2.4 distal radius locking compression plate. 2D (anterior-posterior and lateral) and 3D (rotational) fluoroscopic images were taken as well as computed tomographies. Fluoroscopic images, Cone Beam CT (CBCT), 360° rotating sequences (so called "Movies") and CT scans were co-evaluated by a specialist orthopedic surgeon and a specialist radiologist regarding quality of fracture reduction, position of plate, position of the three distal locking screws and position of the three diaphyseal screws. In reference to gold standard CT, sensitivity and specifity were analyzed. RESULTS: "Movie" showed highest sensitivity for detection of insufficient fracture reduction (88%). Sensitivity for detection of incorrect position of plate was 100% for CBCT and 90% for "Movie." For intraarticular position of screws, 2D fluoroscopy and CBCT showed highest sensitivity and specifity (100 and 91%, respectively). Regarding detection of only marginal intraarticular position of screws, sensitivity and specifity of 2D fluoroscopy reached 100% (CBCT: 100 and 83%). "Movie" showed highest sensitivity for detection of overlapping position of screws (100%). When it comes to specifity, CBCT achieved 100%. Regarding detection of only marginal overlapping position of screws, 2D fluoroscopy and "Movie" showed highest sensitivity (100%). CBCT achieved highest specifity (100%). CONCLUSION: As for assessment of quality of fracture reduction and detection of incorrect position of plate as well as overlapping position of the three diaphyseal screws CBCT and "Movie" are comparable to CT - especially when combined. Particularly sensitivity is high compared to standard 2D fluoroscopy.