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2.
Orthopade ; 48(9): 768-775, 2019 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-31463543

RESUMEN

BACKGROUND: Soft tissue sarcomas (STS) are a rare and heterogeneous group of malignant tumors that arise from the mesenchymal tissue. STS can form anywhere in the human body, with the extremities being preferred sites of predilection. TREATMENT: A fundamental pillar of treatment is the surgical resection of soft tissue sarcomas. The goal is always an R0 resection with a safety margin. There is no consensus in the literature about the desired tumor-free resection margin. The decisive factors for these resection margins are histopathology, presence of anatomical barriers (capsule, tendon, fascia, cartilage, periosteum) and possibilities of (neo-) adjuvant therapy. DISCUSSION: References in the literature support the role of resection margins as a predictor of local recurrence. Regarding the role of resection margins in overall survival, available data is divergent. There are known prognostic factors that influence overall survival, such as histological subtype, tumor size, tumor grading, and presence of metastases. So far, several studies have attempted to quantify the margins of resection, but no consensus has been reached, and debates are ongoing. When analyzing all the results of the data in the literature, it seems appropriate to aim for a negative resection margin >1 mm including an anatomical border structure, if possible.


Asunto(s)
Sarcoma/cirugía , Neoplasias de los Tejidos Blandos/cirugía , Humanos , Márgenes de Escisión , Recurrencia Local de Neoplasia , Pronóstico , Estudios Retrospectivos
3.
Orthopade ; 48(9): 752-759, 2019 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-31444515

RESUMEN

BACKGROUND: Bone metastases are the most common malignant bone tumours and most commonly occur in the spine, pelvis, proximal femur and proximal humerus. Prostate and breast cancer most often metastasize to the bone. DIAGNOSTICS: In patients with a history of tumours and local unspecific pain in the back and extremities, further diagnostic examinations should be performed. For the initial diagnosis a conventional radiograph of the whole bone in two planes is sufficient. For further diagnostics, the imaging may be supplemented with CT, MRI, scintigraphy and a PET-CT (PET-MRI) if the findings are not inconspicuous on the x­ray. An indication for biopsy exists if the tumor cannot be classified, especially in solitary findings with or without previous tumor anamnesis. THERAPY: Surgical indications for bone metastases are a pathological fracture, an impending fracture, a solitary late metastasis, radiation-resistant osteolysis and therapy-resistant pain. In solitary metastases, the prognosis for patients can be significantly improved by a wide (R0 resection) depending on the primary tumour. For multiple metastases the restoration of mobility and improvement of the quality of life are in the foreground. Depending on the life expectancy and other factors, such as the location of the metastases osteosynthesis, implantations of dual head prothesis, total joint arthroplasty and tumor endoprostheses can be performed.


Asunto(s)
Neoplasias Óseas/terapia , Fémur , Fracturas Espontáneas , Humanos , Masculino , Tomografía Computarizada por Tomografía de Emisión de Positrones , Calidad de Vida
4.
J Pediatr Neurosci ; 14(1): 30-35, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31316640

RESUMEN

AIMS AND OBJECTIVES: Cerebral palsy (CP) is a common motor disability in children. This study aimed at elaborating various comorbidities and etiologies and also at correlating motor disability with other disabilities. MATERIAL AND METHODS: This hospital-based study was conducted in the outpatient department of a tertiary care hospital in Delhi on 160 children with CP in the age group 2-15 years. A detailed history taking and examination were conducted for each patient and appropriate investigations were performed. RESULTS: Most patients, that is 64.4%, were younger than 5 years of age and 72.5% were males. Most common etiology was birth asphyxia (41.9%). Maximum patients were of bilateral spastic (spastic quadriplegic) CP accounting 43.1%. Intellectual disability was the most common comorbidity across all subtypes of CP followed by epilepsy. Comorbidities such as epilepsy and all visual problems except optic atrophy were more common in spastic quadriplegic CP. Hearing, speech impairment, and optic atrophy were more common in dyskinetic CP. Chewing, swallowing, and drooling problems were more common in spastic quadriplegic CP. CONCLUSION: Most common risk factor of CP is birth asphyxia; thus, by improving health care facilities, its incidence can be reduced. CP affects not only motor functions but also other important functions of body as well, and the more severe the motor disabilities, the more are other comorbidities and their intensity also increases with that of the intensity of brain insult.

6.
Orthopade ; 48(4): 315-321, 2019 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-30868208

RESUMEN

BACKGROUND: Instability is a common cause of failure in primary and, especially, revision total hip arthroplasty. The reasons for instability include implant malpositioning, impingement, inadequate offset reconstruction, and gluteal insufficiency. Impingement following THA and revision THA is divided into prosthetic and bony impingement, and in addition to instability also causes pain in the area of the hip joint. Offset reconstruction during revision THA is of particular biomechanical importance, since insufficient reconstruction leads not only to instability and pain but also to dislocation. Abductor deficiency often occurs after revision THA and leads to a change in gait pattern, instability and pain. AIM: Current diagnostic and treatment procedures for instability, impingement, insufficient offset reconstruction and abductor deficiency after THA and revision THA are summarized. RESULTS AND DISCUSSION: Diagnosis of an instable THA and painful THA includes patient history, physical examination and medical imaging. Thus, in almost all cases, the cause can be determined and treated. Dislocation after primary THA in the early postoperative period can often be treated conservatively if accurate component placement is observed, while a late-onset and recurrent dislocation after primary and revision THA usually needs surgical procedures. To avoid bony and prosthetic THA impingement intraoperative control is absolutely necessary. If possible, the offset reconstruction is based on the condition of the native hip joint and can be achieved by using modular prostheses, neck adapters and different head lengths. Abductor deficiency also occurs frequently after revision THA and can be treated surgically if severe clinical symptoms and fatty degeneration of the abductors have been diagnosed.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Prótesis de Cadera , Luxaciones Articulares , Articulación de la Cadera , Humanos , Falla de Prótesis , Reoperación
7.
Orthopade ; 48(4): 282-291, 2019 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-30770946

RESUMEN

BACKGROUND: Providing the hip with an endoprosthesis is one of the most common orthopedic interventions in Germany. The long-term success of such a procedure depends on the consideration of the loads due to muscle and joint forces in the planning and operative care. Patient-specific information of forces acting in vivo is not available to the surgeon in clinical routine today. This is where biomechanical modeling comes in. PROCEDURES: A field of activity of biomechanical modeling is the development of methods and procedures for the precise analysis and simulation of endoprosthetic supplies. The aim was to show the possibilities of biomechanical modeling in total hip arthroplasty by means of two examples (sensitivity analysis and pre-/postoperative comparison of intervention outcome). RESULTS: The results of the sensitivity analysis showed that by modeling the position of an optimal reconstruction of the hip rotational center can be found and the forces acting on the hip joint minimized. In the case of the pre-/postoperative comparison, it can be analyzed whether there has been a decrease or increase of load postoperatively, respectively, or whether the conditions are considered to be approximately equal to the preoperative situation. In the future, biomechanical modeling will be able to significantly improve long-term function by reducing wear and optimizing muscular function of the joint. Therefore, the routine use of validated musculoskeletal analysis in the context of standardized preoperative planning and intraoperative navigation-based implementation should be considered. Thus, validated analyses of musculoskeletal loads not only contribute to the extension of basic knowledge but also to the optimization of endoprosthetic care through their integration into the clinical workflow.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Fenómenos Biomecánicos , Alemania , Articulación de la Cadera , Humanos , Músculos
8.
Clin Microbiol Infect ; 25(3): 380.e9-380.e16, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29906596

RESUMEN

OBJECTIVES: Hospital-based surveillance of influenza and acute respiratory infections relies on International Classification of Diseases (ICD) codes and hospital laboratory reports (Standard-of-Care). It is unclear how many cases are missed with either method, i.e. remain undiagnosed/coded as influenza and other respiratory virus infections. Various influenza-like illness (ILI) definitions co-exist with little guidance on how to use them. We compared the diagnostic accuracy of standard surveillance methods with a prospective quality management (QM) programme at a Berlin children's hospital with the Robert Koch Institute. METHODS: Independent from routine care, all patients fulfilling pre-defined ILI-criteria (QM-ILI) participated in the QM programme. A separate QM team conducted standardized clinical assessments and collected nasopharyngeal specimens for blinded real-time quantitative PCR for influenza A/B viruses, respiratory syncytial virus, adenovirus, rhinovirus and human metapneumovirus. RESULTS: Among 6073 individuals with ILI qualifying for the QM programme, only 8.7% (528/6073) would have undergone virus diagnostics during Standard-of-Care. Surveillance based on ICD codes would have missed 61% (359/587) of influenza diagnoses. Of baseline ICD codes, 53.2% (2811/5282) were non-specific, most commonly J06 ('acute upper respiratory infection'). Comparison of stakeholder case definitions revealed that QM-ILI and the WHO ILI case definition showed the highest overall sensitivities (84%-97% and 45%-68%, respectively) and the CDC ILI definition had the highest sensitivity for influenza infections (36%, 95% CI 31.4-40.8 for influenza A and 48%, 95% CI 40.5-54.7 for influenza B). CONCLUSIONS: Disease-burden estimates and surveillance should account for the underreporting of cases in routine care. Future studies should explore the effect of ILI screening and surveillance in various age groups and settings. Diagnostic algorithms should be based on the WHO ILI case definition combined with targeted testing.


Asunto(s)
Garantía de la Calidad de Atención de Salud/estadística & datos numéricos , Infecciones del Sistema Respiratorio/diagnóstico , Nivel de Atención/estadística & datos numéricos , Virosis/diagnóstico , Virus/aislamiento & purificación , Adolescente , Niño , Preescolar , Femenino , Hospitales , Humanos , Lactante , Recién Nacido , Gripe Humana/clasificación , Gripe Humana/diagnóstico , Clasificación Internacional de Enfermedades/normas , Masculino , Nasofaringe/virología , Vigilancia de la Población , Estudios Prospectivos , Garantía de la Calidad de Atención de Salud/normas , Reacción en Cadena en Tiempo Real de la Polimerasa , Infecciones del Sistema Respiratorio/clasificación , Infecciones del Sistema Respiratorio/virología , Nivel de Atención/normas , Virosis/clasificación
9.
Knee Surg Sports Traumatol Arthrosc ; 27(3): 685-691, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29785448

RESUMEN

PURPOSE: With the growing interest in resurfacing procedures, several new implants have been recently introduced for isolated patello-femoral joint arthroplasty (PFA). However, not much data are available for these new techniques or about the right indications for each type of implant. METHODS: Out of a retrospective cohort of 20 inlay PFA, 11 PFA with an elevated Insall-Salvati index and an increased patello-femoral congruence angle showed an initial satisfactory result, but presented thereafter with recurrent pain and "clunk" phenomena. They were all revised after a median time of 25 months (range 8-28 months) into an onlay technique PFA and analyzed for their failure mode and revision technique. RESULTS: Clinical symptoms such as clunking, as well as abraded areas craniolateral of the inlay implant found intraoperatively, were the main observations of this study. The modified Insall-Salvati index (mISI) was significantly higher in the revised knees compared to the unrevised (median 1.8 versus 1.6; p = 0.041). VAS and KSS significantly improved after revision (median VAS reduction in pain of 4.0 points, median KSS improvement of 20.0 points; p < 0.05). CONCLUSION: Patients with high-normal patellar height index or patella alta, as well as a craniolateral type of arthritis with additional lateralization, should be considered contra-indicated for an inlay technique PFA. They could be considered for a PFA system reaching further proximal into the distal femur. An onlay PFA can be an option for early revision of failed inlay implants. The clinical relevance of this study is that patella alta and patellar subluxation are more difficult to adjust for with an inlay PFJ component. LEVEL OF EVIDENCE: Level IV.


Asunto(s)
Artroplastia/métodos , Articulación Patelofemoral/cirugía , Prótesis e Implantes , Insuficiencia del Tratamiento , Adulto , Anciano , Estudios de Cohortes , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reoperación , Estudios Retrospectivos
10.
J Public Health (Oxf) ; 41(4): 840-849, 2019 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-30423143

RESUMEN

BACKGROUND: Unprecedented numbers of migrants have arrived in Europe, including children and adolescents. Little is known about their unique health needs. Prospective data collection has been sparse. Mobile applications may help to facilitate global health surveillance. METHODS: A pre-validated survey instrument was converted into a mobile application covering self-reported exposures and disruptions of healthcare before/during migration, communicable and non-communicable diseases. Participation was voluntary, anonymous and confidential. RESULTS: Data were obtained from 405 migrant children and adolescents in Berlin, Germany, between 7 October 2015 and 15 March 2016 (median age 19 years, range: 1-24; 80.7% males) with the majority from Syria (62.5%), Afghanistan (9.1%) and Iraq (8.2%). In total, 55% were without family, 64% registered asylum-seekers with access to healthcare; 54% had seen a doctor since arrival, with colds or respiratory complaints (37.5 and 13.6%), followed by pain (26.7%) gastrointestinal (12.4%) and skin problems (11.1%). Underlying conditions were reported in 15.6%, predominantly asthma. Overall, 73% reported being up-to date on immunizations, but only 22% held a vaccination record with 46.4% having lost it during migration. CONCLUSIONS: The lack of medical and immunization records among newly arrived migrants provides a challenge to healthcare systems. Mobile applications offer rapid screening tools in times of crisis, helping stakeholders with timely information.


Asunto(s)
Aplicaciones Móviles , Evaluación de Necesidades , Migrantes/estadística & datos numéricos , Adolescente , Afganistán/etnología , Niño , Preescolar , Femenino , Alemania/epidemiología , Estado de Salud , Humanos , Lactante , Irak/etnología , Masculino , Vigilancia de la Población/métodos , Siria/etnología , Migrantes/psicología , Adulto Joven
11.
Orthopade ; 47(9): 751-756, 2018 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-30094647

RESUMEN

BACKGROUND: Avascular necrosis of the femoral head is a progressive perfusion disorder of the hip joint. Progress in avascular necrosis causes structural damage to the affected joint, often requiring total hip replacement. AIM: This article is intended to give the reader an overview of the current literature on total hip replacement of patients with an avascular necrosis of the femoral head. RESULTS: Before 1990, patients with avascular necrosis of the femoral head had significantly higher revision rates after total hip replacement. Recent studies, however, showed no significant differences in clinical outcomes after total hip replacement in femoral head necrosis and primary osteoarthritis. Despite the young age of the patients, good long-term clinical results can be expected even in patients with an avascular necrosis of the femoral head after total hip replacement.


Asunto(s)
Artroplastia de Reemplazo de Cadera , Necrosis de la Cabeza Femoral , Osteoartritis , Necrosis de la Cabeza Femoral/complicaciones , Necrosis de la Cabeza Femoral/cirugía , Articulación de la Cadera , Humanos , Osteoartritis/complicaciones
12.
Public Health ; 158: 163-175, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29628203

RESUMEN

OBJECTIVES: Little is known about the psychological trauma experienced by children and young adults (CYAs) following displacement after natural disasters vs migration from conflict zones. In both instances, the decision to leave is usually cast by the family, and the life of CYAs is suddenly disrupted by external circumstances. STUDY DESIGN: An anonymous survey. METHODS: The same survey instrument, provided by the National Child Traumatic Stress Network (NCTSN), was used to survey self-reported health needs among CYAs during the aftermath of Hurricane Katrina (Health Survey for Children and Adolescents After Katrina) in October 2005-February 2006 and again during the peak of refugee arrivals in Berlin between October 2015 and March 2016. A weighted index to measure cumulative exposure to traumatic stresses during migration was developed along with an unweighted psychological impact score based on the 22-item NCTS psychological impact questionnaire. Spearman's correlation coefficient (rho) was used to assess the correlation between age and the two psychological impact indices. The two-tailed t-test was used to investigate differences in trauma experienced and psychological impact by gender. Logistic regression was used to investigate differences in types of traumatic stress experienced and psychological impact among CYAs displaced because of Hurricane Katrina and those seeking asylum in Berlin. RESULTS: The Katrina cohort included a total of 1133 CYAs, the Berlin cohort, a total of 405 CYAs. The median age in the Katrina cohort was 6.73 years (standard deviation [SD] 5.67, range 0-24; 50.13% males) compared with 17.64 years (SD, range 0-24; 83% males) in the Berlin cohort. Comparative analyses were adjusted to age and gender and revealed significant differences between the two cohorts, both with regards to the amount of trauma experienced and the psychological impact. A statistically significant and moderate positive correlation was observed between trauma experienced and psychological impact of migration in the refugee population (rho = 0.4955, P < 0.001); the correlation was less pronounced but still significant in the Katrina cohort (rho = 0.0942, P = 0.0015). Free-text responses revealed that in addition to common concerns about health, housing and safety, refugees were also pre-occupied with language acquisition and the adaptation to a new culture. CONCLUSIONS: The observed differences in the experience and the consequences of trauma in displaced CYAs warrant additional investigation. It was replicated that human-made disaster seems to show more traumatising potential than natural disaster. Stakeholders need to be aware of the potential medium and long-term consequences of migration/evacuation and allocate resources accordingly.


Asunto(s)
Conflictos Armados/psicología , Tormentas Ciclónicas , Desastres , Migración Humana/estadística & datos numéricos , Trauma Psicológico/psicología , Refugiados/psicología , Adolescente , Berlin , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Refugiados/estadística & datos numéricos , Encuestas y Cuestionarios , Estados Unidos , Adulto Joven
13.
Orthopade ; 46(11): 907-913, 2017 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-28980022

RESUMEN

BACKGROUND: Cartilage is an avascular, alymphatic and non-innervated tissue with limited intrinsic repair potential. The high prevalence of cartilage defects and their tremendous clinical importance are a challenge for all treating physicians. AIM: This article provides the reader with an overview about current cartilage treatment options and their clinical outcome. METHODS: Microfracture is still considered the gold standard in the treatment of small cartilage lesions. Small osteochondral defects can be effectively treated with the autologous osteochondral transplantation system. Larger cartilage defects are successfully treated by autologous membrane-induced chondrogenesis (AMIC) or by membrane-assisted autologous chondrocyte implantation (MACI). CONCLUSION: Despite limitations of current cartilage repair strategies, such procedures can result in short- and mid-term clinical improvement of the patients. Further developments and clinical studies are necessary to improve the long-term outcome following cartilage repair.


Asunto(s)
Cartílago/fisiopatología , Regeneración/fisiología , Cartílago/lesiones , Cartílago/trasplante , Condrocitos/fisiología , Condrocitos/trasplante , Condrogénesis/fisiología , Fracturas por Estrés/fisiopatología , Humanos , Trasplante Autólogo
15.
Orthopade ; 46(11): 894-906, 2017 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-28936540

RESUMEN

Morphological imaging of cartilage at high resolution allows the differentiation of chondral and osteochondral lesions. Nowadays, magnetic resonance imaging is the principal diagnostic tool in the assessment of cartilage structure and composition. Conventional radiography, computed tomography, ultrasound or optical coherence tomography are adjunct diagnostic modalities in the assessment of cartilage pathologies. The present article discusses the up-to-date diagnostic practice of cartilage imaging in terms of its scientific basis and current clinical status, requirements, techniques and image interpretation. Innovations in the field such as functional MRI are discussed as well due to their mid- to long-term clinical perspective.


Asunto(s)
Enfermedades Óseas/diagnóstico por imagen , Enfermedades de los Cartílagos/diagnóstico por imagen , Cartílago Articular/diagnóstico por imagen , Imagen por Resonancia Magnética , Humanos , Sensibilidad y Especificidad , Tomografía de Coherencia Óptica , Ultrasonografía
16.
Orthopade ; 46(11): 919-927, 2017 Nov.
Artículo en Alemán | MEDLINE | ID: mdl-28852793

RESUMEN

BACKGROUND: Cartilage defects around the knee joint frequently occur in the region of the medial femoral condyle and the retropatellar cartilage surface. The distinction between local cartilage defects and large area degenerative cartilage lesions is very important for both prognosis and surgical therapy. The size and position of the lesion, the underlying pathomechanism and the age of the patient are very important factors which should be considered in the therapy algorithm for optimal cartilage defect restoration. Important cofactors such as stability, long leg axis and muscle balance should be taken into account. AIM: Current procedures for cartilage repair of the knee joint and their results are summarized in this article. In addition, the necessity of precise and comprehensive preoperative clinical and radiological diagnostics is displayed to be able to treat co-pathologies in order to enable a successful repair of the cartilage defect. RESULTS AND CONCLUSIONS: Preoperative planning of cartilage-repair techniques usually includes x­ray images and a magnetic resonance imaging (MRI) examination. If MRI is not available, an arthro-computed tomography could be an alternative. Modern and routinely used procedures for cartilage repair at the knee joint are microfracture, autologous matrix-induced chondrogenesis, autologous chondrocyte transplantation, matrix-induced autologous chondrocyte implantation and osteochondral transplantation. Successful surgical cartilage-repair surgeries require a correct and individualized indication, addressing of copathologies and a standardized rehabilitation that is adapted to the surgical procedure. Evidence-based criteria for an exact time point for the return to sports according to individually operative cartilage repair techniques currently do not exist.


Asunto(s)
Cartílago Articular/lesiones , Cartílago Articular/cirugía , Traumatismos de la Rodilla/cirugía , Autoinjertos , Médula Ósea/fisiopatología , Cartílago Articular/diagnóstico por imagen , Cartílago Articular/fisiopatología , Condrocitos/fisiología , Condrocitos/trasplante , Fracturas por Estrés/fisiopatología , Fracturas por Estrés/cirugía , Humanos , Traumatismos de la Rodilla/diagnóstico por imagen , Traumatismos de la Rodilla/fisiopatología , Articulación de la Rodilla/diagnóstico por imagen , Articulación de la Rodilla/fisiopatología , Articulación de la Rodilla/cirugía , Imagen por Resonancia Magnética , Regeneración/fisiología , Tomografía Computarizada por Rayos X
17.
J Mech Behav Biomed Mater ; 69: 169-177, 2017 05.
Artículo en Inglés | MEDLINE | ID: mdl-28086148

RESUMEN

Limited availability of fresh intervertebral discs (IVDs) necessitates the use of frozen-thawed samples in biomechanical investigations. Several authors have reported the mechanical properties of frozen-thawed IVDs, but few studies have investigated the effects of storage temperature and cooling rate. The validity and reliability of the applied freezing-thawing procedures are still relatively unknown. The study aims to compare the mechanical responses of fresh porcine IVDs and porcine IVDs, which were frozen at different freezing temperatures with a controlled-rate cooling process and then thawed. The specimens were obtained from pigs aged 6 months. A total of 18 functional spine units (FSUs) were taken from seven porcine lumbar spines (L1-L6). The specimens were then split into three groups. The first group was tested fresh immediately and the other two groups were frozen at the same cooling rate and stored at -20°C and -80°C, respectively, before testing. The period of storage ranged between 12 and 43 days. The frozen specimens were thawed for 9h at room temperature before the tests. A special IVD bioreactor, which maintained the realistic behaviour of IVDs under various loading conditions, was developed. The analysis of variance (ANOVA) was used to determine if the observed results were statistically significant. The results indicated that frozen storage at -20°C decreases the comprehensive stiffness. In contrast, freezing to -80°C did not seem to have any effect on the mechanical properties of IVDs. No significant differences in outcome were observed for the samples, which had different spine levels. The study confirmed the reliability and usability of frozen-thawed samples stored at -80°C for biomechanical investigations.


Asunto(s)
Reactores Biológicos , Criopreservación , Disco Intervertebral/fisiología , Vértebras Lumbares/fisiología , Animales , Fenómenos Biomecánicos , Congelación , Reproducibilidad de los Resultados , Porcinos
18.
J Tissue Eng Regen Med ; 11(11): 2988-2998, 2017 11.
Artículo en Inglés | MEDLINE | ID: mdl-27641068

RESUMEN

Mesenchymal stem cells (MSC) are precursor cells of mesodermal tissue and, because of their trophic phenotype, they are known to play beneficial roles in wound healing. In addition, various tissue engineering strategies are based on MSC/biomaterial constructs. As the isolation and expansion of MSCs is a long-term process, a major goal is to develop an endogenous stem cell recruitment system that circumvents all ex vivo steps generally used for tissue engineering. Therefore collagen and silk fibroin were loaded with hepatocyte growth factor (HGF), a chemoattractant for MSCs. Collagen was mixed with HGF during polymerization, while silk fibroin and HGF were produced as fusion proteins by transgenic silkworms. To demonstrate release of active HGF, enzyme-linked immunosorbent assay, in vitro migration assays and animal studies were performed to demonstrate MSC migration in vivo, followed by detailed examinations of the immunological effects of the biomaterials. Hepatocyte growth factor was released burst-like, both from silk fibroin and collagen during the first 8 h and gradually for up to 168 h in vitro. Directed migration in vitro was demonstrated when MSCs were exposed to HGF. In vivo, HGF-loaded collagen and silk fibroin were tolerated as subcutaneous implants. In addition, it was proved that endogenous MSCs were recruited from the local environment. These results show for the first time recruitment of endogenous MSCs to HGF-loaded collagen (fast degradable) and silk fibroin scaffolds (long-term degradable) in vitro and in vivo. This knowledge could be applied to make off-the-shelf, readily available constructs for use in patients with chronic wound or burns. Copyright © 2016 John Wiley & Sons, Ltd.


Asunto(s)
Materiales Biocompatibles , Movimiento Celular/efectos de los fármacos , Factor de Crecimiento de Hepatocito , Células Madre Mesenquimatosas/metabolismo , Heridas y Lesiones/terapia , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacocinética , Materiales Biocompatibles/farmacología , Implantes de Medicamentos/química , Implantes de Medicamentos/farmacocinética , Implantes de Medicamentos/farmacología , Femenino , Fibroínas/química , Fibroínas/farmacocinética , Fibroínas/farmacología , Factor de Crecimiento de Hepatocito/química , Factor de Crecimiento de Hepatocito/farmacocinética , Factor de Crecimiento de Hepatocito/farmacología , Humanos , Masculino , Células Madre Mesenquimatosas/patología , Heridas y Lesiones/metabolismo , Heridas y Lesiones/patología
19.
J Orthop ; 14(1): 95-103, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27829733

RESUMEN

PURPOSE: The aim was to prove the possibility of creating an exact module of knee cartilage defects using 3D printing. METHODS: Defects were created in cadaver knees. CT-arthrography and 3-Tesla MRI were performed. Based on CTA images a model of the cartilage was created using 3D printing. Defect-sizes in the imaging modalities were compared. RESULTS: Estimated lesion area in 3D model differed approximately 5% comparing to the defect sizes in knees. MRI underestimated the defect on average of 12%, whereas the CTA overestimated the defect about 3%. CONCLUSIONS: We proved the feasibility of creating an accurate module of knee cartilage.

20.
Mediators Inflamm ; 2017: 4786170, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-29362520

RESUMEN

Cathepsin S is a cysteine protease and regulator of autophagy with possible involvement in periodontitis. The objective of this study was to investigate whether cathepsin S is involved in the pathogenesis of periodontal diseases. Human periodontal fibroblasts were cultured under inflammatory and infectious conditions elicited by interleukin-1ß and Fusobacterium nucleatum, respectively. An array-based approach was used to analyze differential expression of autophagy-associated genes. Cathepsin S was upregulated most strongly and thus further studied in vitro at gene and protein levels. In vivo, gingival tissue biopsies from rats with ligature-induced periodontitis and from periodontitis patients were also analyzed at transcriptional and protein levels. Multiple gene expression changes due to interleukin-1ß and F. nucleatum were observed in vitro. Both stimulants caused a significant cathepsin S upregulation. A significantly elevated cathepsin S expression in gingival biopsies from rats with experimental periodontitis was found in vivo, as compared to that from control. Gingival biopsies from periodontitis patients showed a significantly higher cathepsin S expression than those from healthy gingiva. Our findings provide original evidence that cathepsin S is increased in periodontal cells and tissues under inflammatory and infectious conditions, suggesting a critical role of this autophagy-associated molecule in the pathogenesis of periodontitis.


Asunto(s)
Catepsinas/fisiología , Periodontitis/etiología , Adolescente , Adulto , Animales , Autofagia/fisiología , Catepsinas/análisis , Células Cultivadas , Niño , Femenino , Encía/metabolismo , Humanos , Masculino , Periodontitis/enzimología , Ratas , Adulto Joven
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