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1.
Rhinology ; 61(1): 12-23, 2023 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-36323438

RESUMEN

BACKGROUND: Chemosensory dysfunction (CD) has been reported as a common symptom of SARS-CoV-2 infection, but it is not well understood whether and for how long changes of smell, taste and chemesthesis persist in infected individuals. METHODOLOGY: Unselected adult residents of the German federal state of Schleswig-Holstein with Polymerase Chain Reaction (PCR)-test-confirmed SARS-CoV-2 infection were invited to participate in this large cross-sectional study. Data on the medical history and subjective chemosensory function of participants were obtained through questionnaires and visual analogue scales (VAS). Olfactory function (OF) was objectified with the Sniffin Sticks test (SST), including threshold (T), discrimination (D) and identification (I) test as well as summarized TDI score, and compared to that in healthy controls. Gustatory function (GF) was evaluated with the suprathreshold taste strips (TS) test, and trigeminal function was tested with an ampoule containing ammonia. RESULTS: Between November 2020 and June 2021, 667 infected individuals (mean age: 48.2 years) were examined 9.1 months, on average, after positive PCR testing. Of these, 45.6% had persisting subjective olfactory dysfunction (OD), 36.2% had subjective gustatory dysfunction (GD). Tested OD, tested GD and impaired trigeminal function were observed in 34.6%, 7.3% and 1.8% of participants, respectively. The mean TDI score of participants was significantly lower compared to healthy subjects. Significant associations were observed between subjective OD and GD, and between tested OD and GD. CONCLUSION: Nine months after SARS-CoV-2 infection, OD prevalence is significantly increased among infected members of the general population. Therefore, OD should be included in the list of symptoms collectively defining Long-COVID.


Asunto(s)
COVID-19 , Trastornos del Olfato , Adulto , Humanos , Persona de Mediana Edad , Estudios Transversales , Trastornos del Olfato/epidemiología , Trastornos del Olfato/etiología , Trastornos del Olfato/diagnóstico , SARS-CoV-2 , Síndrome Post Agudo de COVID-19 , Olfato , Trastornos del Gusto/epidemiología , Trastornos del Gusto/etiología
2.
Chaos ; 31(3): 033140, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33810764

RESUMEN

Modeling, simulation, and analysis of interacting agent systems is a broad field of research, with existing approaches reaching from informal descriptions of interaction dynamics to more formal, mathematical models. In this paper, we study agent-based models (ABMs) given as continuous-time stochastic processes and their pathwise approximation by ordinary and stochastic differential equations (SDEs) for medium to large populations. By means of an appropriately adapted transfer operator approach, we study the behavior of the ABM process on long time scales. We show that, under certain conditions, the transfer operator approach allows us to bridge the gap between the pathwise results for large populations on finite timescales, i.e., the SDE limit model, and approaches built to study dynamical behavior on long time scales like large deviation theory. The latter provides a rigorous analysis of rare events including the associated asymptotic rates on timescales that scale exponentially with the population size. We demonstrate that it is possible to reveal metastable structures and timescales of rare events of the ABM process by finite-length trajectories of the SDE process for large enough populations. This approach has the potential to drastically reduce computational effort for the analysis of ABMs.

3.
Orthopade ; 43(2): 136-42, 2014 Feb.
Artículo en Alemán | MEDLINE | ID: mdl-24504624

RESUMEN

BACKGROUND: This study was conducted to evaluate the current status of pediatric hip sonography at German university hospitals. MATERIAL AND METHODS: A questionnaire was sent to all heads of orthopedic departments in Germany. They were asked to give details of the technique and instrumentation used for hip ultrasound examination, local organization of consultation and options for advanced training of students and staff. RESULTS: The return rate of the questionnaires was 93.9 %. Pediatric hip ultrasonography was performed at every university hospital by staff of the orthopedic and trauma departments (n = 31, 100 %). A well-established tradition of teaching both medical students and physicians on this topic was reported by many departments. Courses with a focus on pediatric hip sonography were organized in 25.8 % of the German university hospitals. In the majority of the responding orthopedic and trauma departments a 7.5 MHz linear transducer for ultrasound examination (93.5 %), a foot switch for rapid freezing of the ultrasound image (93.5 %) and a cradle for positioning the infant (100 %) were used. A guided probe device recommended by Graf was only used in 35.5 % of the departments. Evaluation of the sonograms was performed in 19 of the clinics (61.3 %) in the classical way on printed paper strips. CONCLUSIONS: This survey documented the high importance of pediatric hip sonography in German university hospitals. Quality controls in the orthopedic departments are carried out internally. For this reason both the implementation of standardized training courses and the schooling of well-trained instructors are mandatory.


Asunto(s)
Hospitales Universitarios/estadística & datos numéricos , Ortopedia/educación , Pediatría/educación , Guías de Práctica Clínica como Asunto , Pautas de la Práctica en Medicina/estadística & datos numéricos , Ultrasonografía/estadística & datos numéricos , Ultrasonografía/normas , Niño , Preescolar , Femenino , Alemania , Adhesión a Directriz/estadística & datos numéricos , Hospitales Universitarios/normas , Humanos , Lactante , Recién Nacido , Masculino , Ortopedia/normas , Pediatría/normas , Pautas de la Práctica en Medicina/normas , Encuestas y Cuestionarios
4.
Eur Heart J Digit Health ; 3(4): 610-625, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36710894

RESUMEN

Aims: Simplified detection of atrial arrhythmias via consumer-electronics would enable earlier therapy in at-risk populations. Whether this is feasible and effective in older populations is not known. Methods and results: The fully remote, investigator-initiated Smartphone and wearable detected atrial arrhythmia in Older Adults Case finding study (Smart in OAC-AFNET 9) digitally enrolled participants ≥65 years without known atrial fibrillation, not receiving oral anticoagulation in Germany, Poland, and Spain for 8 weeks. Participants were invited by media communications and direct contacts. Study procedures adhered to European data protection. Consenting participants received a wristband with a photoplethysmography sensor to be coupled to their smartphone. The primary outcome was the detection of atrial arrhythmias lasting 6 min or longer in the first 4 weeks of monitoring. Eight hundred and eighty-two older persons (age 71 ± 5 years, range 65-90, 500 (57%) women, 414 (47%) hypertension, and 97 (11%) diabetes) recorded signals. Most participants (72%) responded to adverts or word of mouth, leaflets (11%) or general practitioners (9%). Participation was completely remote in 469/882 persons (53%). During the first 4 weeks, participants transmitted PPG signals for 533/696 h (77% of the maximum possible time). Atrial arrhythmias were detected in 44 participants (5%) within 28 days, and in 53 (6%) within 8 weeks. Detection was highest in the first monitoring week [incidence rates: 1st week: 3.4% (95% confidence interval 2.4-4.9); 2nd-4th week: 0.55% (0.33-0.93)]. Conclusion: Remote, digitally supported consumer-electronics-based screening is feasible in older European adults and identifies atrial arrhythmias in 5% of participants within 4 weeks of monitoring (NCT04579159).

5.
Eur Cell Mater ; 21: 384-95, 2011 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-21574135

RESUMEN

Nanofibre scaffolds are suitable tools for bone tissue engineering. Mimicking the extracellular matrix, they allow for cell growth and differentiation. However, in large 3D scaffolds, uniform cell colonisation presents an unsolved problem. Our aim was to design and analyse a method of colonising nanofibre scaffolds, combining electrospinning of fibres and electrospraying of cells, to determine its impact on cell survival, growth, and gene expression. The osteoblast-like cell line MG63 was suspended in medium and electrosprayed into growing scaffolds of poly-(l-lactic acid) (PLLA) or PLLA/Col-I blend nanofibres. Fluorescein diacetate (FDA) staining was used to determine survival and growth over a 22 d culture period. Expression of osteocalcin (OC) and type I collagen (Col-I) genes was determined by real time PCR. Fluorescence microscopy was used to analyse Col-I and OC deposition, as well as cell densities. While spraying distance and cell density in the spraying solution influenced survival and cell density, the combination of electrospinning and electrospraying did not negatively influence the maintenance of the osteoblast phenotype. Furthermore, VEGF induction in response to hypoxia was not suppressed, but modulated by polymer composition. Therefore, simultaneous electrospinning and electrospraying is a suitable tool in producing nanofibre based 3D cell seeded scaffolds.


Asunto(s)
Regeneración Ósea , Ácido Láctico , Nanofibras , Osteoblastos/citología , Polímeros , Andamios del Tejido , Técnicas de Cultivo de Célula , Hipoxia de la Célula , Línea Celular Tumoral , Supervivencia Celular , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Humanos , Osteoblastos/metabolismo , Osteocalcina/genética , Osteocalcina/metabolismo , Poliésteres , Ingeniería de Tejidos , Transcripción Genética , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismo
6.
Knee Surg Sports Traumatol Arthrosc ; 19(10): 1780-7, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21340630

RESUMEN

PURPOSE: The aim of the study was to evaluate the stabilizing function of the long head of biceps tendon (LHB) and its tension, both without and with the presence of SLAP lesion to analyze a potentially occurring humeral chondral print of LHB with consecutive glenohumeral chondral lesions in SLAP lesions. METHODS: Testings were performed on 21 fresh frozen human cadaver shoulders with intact shoulder girdle by a 5 axis industrial robot with a force/moment sensor and 20 N joint compression, 50 N force in anterior, posterior, anterosuperior, and anteroinferior direction, and 0°, 30°, 60° of abduction. LHB was connected over a force measuring sensor with 5 N and 25 N preload. A type IIC SLAP lesion was created arthroscopically. RESULTS: A significant increase in anterior and anteroinferior translation was evaluated, whereas the LHB tension increased significantly in at most anterior and anterosuperior direction. The highest increase in translation and LHB tension after SLAP lesion was measured in anterior translation in at most 60° of abduction. The glenohumeral translation was significantly higher in SLAP lesions without LHB tenotomy than after isolated LHB tenotomy. CONCLUSIONS: SLAP lesions lead to increased glenohumeral translation and concurrently LHB tension and load in at most anterior direction. The increased anterior glenohumeral instability and the increased LHB load pressing on the humeral head might cause glenohumeral chondral lesions with a typical chondral print-like lesion on the humeral head underneath the LHB.


Asunto(s)
Traumatismos del Brazo/fisiopatología , Cabeza Humeral/lesiones , Inestabilidad de la Articulación/fisiopatología , Osteoartritis/etiología , Lesiones del Hombro , Traumatismos de los Tendones/fisiopatología , Traumatismos del Brazo/etiología , Artroscopía , Fenómenos Biomecánicos , Cartílago/lesiones , Cartílago/fisiopatología , Femenino , Cavidad Glenoidea/fisiopatología , Humanos , Cabeza Humeral/fisiopatología , Inestabilidad de la Articulación/etiología , Masculino , Articulación del Hombro/fisiopatología , Traumatismos de los Tendones/complicaciones , Tendones/fisiopatología , Tenotomía , Soporte de Peso
7.
Arch Orthop Trauma Surg ; 131(8): 1145-51, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21359871

RESUMEN

PURPOSE: Several studies have investigated the influence of different growth factors on hyaline cartilage regeneration. In a rabbit model, hepatocyte growth factor (HGF) was proven to increase the amount of hyaline-like chondrocytes in a mixed fibro-cartilaginous regenerate of small defects. The aim of the current study was to evaluate whether intra-articular administration of HGF influences the ingrowth of osteochondral grafts in a sheep model. TYPE OF STUDY: Animal experiment. METHODS: Both knee joints of eight sheep were opened surgically and osteochondral grafts were harvested and simultaneously transplanted to the opposite condyle of the same joint. The sheep were divided into two groups of four sheep, resulting in 16 grafts per group. In one group, HGF was administered by bilateral intra-articular injections given three times a week for 4 weeks. The control group received isotonic sodium chloride injections. The animals were killed after 3 months. RESULTS: Histological evaluation showed a complete ingrowth of the osseous part of the osteochondral grafts. A healing or ingrowth at the level of the cartilage could not be observed. Histological evaluation of the transplanted grafts according to the modified Mankin score revealed less degeneration in the cartilage of the HGF group, as compared to the control group. In the HGF group, less cloning of chondrocytes and less irregularities of the articular surface were observed. Importantly, no deleterious effects, such as osteophyte formation, cartilage thickening or synovial proliferation, were found. CONCLUSION: HGF positively influenced the cellularity of the transplanted osteochondral graft, but could not diminish the fissures in the marginal zone of the grafts. CLINICAL RELEVANCE: Marginal zone fissures and degeneration in the absence of HGF may undermine long-term results of autologous osteochondral grafts.


Asunto(s)
Cartílago/trasplante , Condrocitos/efectos de los fármacos , Supervivencia de Injerto/efectos de los fármacos , Factor de Crecimiento de Hepatocito/farmacología , Traumatismos de la Rodilla/cirugía , Articulación de la Rodilla/cirugía , Animales , Cartílago/efectos de los fármacos , Cartílago Articular/lesiones , Cartílago Articular/cirugía , Esquema de Medicación , Factor de Crecimiento de Hepatocito/administración & dosificación , Inyecciones Intraarticulares , Masculino , Ovinos , Cicatrización de Heridas/efectos de los fármacos
8.
Osteoarthritis Cartilage ; 18(6): 849-56, 2010 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20171296

RESUMEN

OBJECTIVE: Recent studies have shown abnormal expression of CD44s and some of its isoforms in many human malignancies, but little is known about the presence of CD44 in chondrosarcoma. In this study the expression of CD44s and two variant isoforms was evaluated. It was assumed that abnormalities in these receptor proteins may be associated with clinical outcome of the patients. METHOD: Thirty paraffin-embedded chondrosarcoma samples were immunostained with monoclonal antibodies for CD44s, CD44v5 and CD44v6. Two independent examiners who were unaware of the clinical status of the patients evaluated the immunohistochemical results. The percentage of CD44-positive cells was scored semiquantitatively. A rate of higher than 10% was considered as overexpression. RESULTS: Among the 30 patients (median age 50 years) there were 22 conventional chondrosarcomas, two dedifferentiated chondrosarcomas, two extraskeletal chondrosarcomas, and one periostal, mesenchymal, clear cell and myxoid chondrosarcoma each. In the immunochemistry staining overexpression (>10% of cells) of CD44s was shown in 56.7% (17 of 30), of CD44v5 in 43.3% (13 of 30) and of CD44v6 in 6.7% (two of 30) of the tumors. Four grade III chondrosarcomas (80%) and 10 (71.4%) grade II chondrosarcomas showed overexpression for CD44s, whereas CD44s was overexpressed in only three (27.3%) grade I chondrosarcomas. Cox regression suggests overexpression of CD44s to be an additional prognostic marker for chondroid bone tumors independent of grading and other covariates. CONCLUSIONS: Overexpression of CD44s correlated significantly with metastatic potential and with poorer survival in patients with chondrosarcoma. CD44s might be an independent additional marker, but small sample size remains to be considered.


Asunto(s)
Condrosarcoma/patología , Receptores de Hialuranos/análisis , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Supervivencia sin Enfermedad , Femenino , Humanos , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Recurrencia Local de Neoplasia , Isoformas de Proteínas/análisis , Adulto Joven
9.
Orthopade ; 39(1): 75-9, 2010 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-19768451

RESUMEN

The use of artifical materials in joint replacement is not self-evident. A paradigm change can be observed. Beginning in the 18th century orthopedic surgery became possible because of a change of the idea of man. Natural growth was seen as ideal solution in orthopedic surgery until the 19th century. Yet in the aftermath the point of view changed to a more technical determined approach. Until the middle of the 20th century the terms "efficieny" and "ability" became more and more important. Joint replacement with artificial materials was generally accepted and led to an enormous accelaration in the development of new materials and surgical techniques.


Asunto(s)
Materiales Biocompatibles/historia , Evolución Cultural/historia , Materiales Manufacturados/historia , Prótesis e Implantes/historia , Historia del Siglo XVIII , Historia del Siglo XIX , Historia del Siglo XX , Historia del Siglo XXI
10.
Eur J Med Res ; 14(4): 157-64, 2009 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-19380288

RESUMEN

OBJECTIVE: Evaluation of gait performance and muscle activity patterns as well as clinical efficacy and safety after single intraarticular injection with hyaluronan compared with triamcinolone in patients with knee osteoarthritis. MATERIALS AND METHODS: This trial evaluated the influence of a single injection of hyaluronan or triamcinolone on gait pattern and muscle activity. For clinical evaluation a visual analogue scale for pain, Lequesne index, and Knee Society Score were used. Quality of life was assessed with the SF-36. RESULTS: The complete analysis was performed in 50 of 60 patients. 26 patients were treated with triamcinolone and 24 with hyaluronan. Hyaluronan treatment led to significant improvement of range of motion at hip and knee. Significant improvement could be either demonstrated for the pain scale, Lequesne and Knee Society score in both groups. Quality of life showed greater improvement in the triamcinolone group. CONCLUSION: Single application of high-viscosity hyaluronan shows superior range of motion and pain reduction as well as improvement in clinical results. Even if there was a lack of significant differences compared to triamcinolone, this therapy classified as safe and effective in the short follow up.


Asunto(s)
Adyuvantes Inmunológicos/administración & dosificación , Marcha/fisiología , Glucocorticoides/administración & dosificación , Ácido Hialurónico/administración & dosificación , Osteoartritis de la Rodilla/tratamiento farmacológico , Triamcinolona/administración & dosificación , Adulto , Anciano , Anciano de 80 o más Años , Método Doble Ciego , Femenino , Estado de Salud , Humanos , Inyecciones Intraarticulares , Masculino , Persona de Mediana Edad , Osteoartritis de la Rodilla/complicaciones , Osteoartritis de la Rodilla/fisiopatología , Dolor/tratamiento farmacológico , Dolor/etiología , Dolor/fisiopatología , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
11.
Knee Surg Sports Traumatol Arthrosc ; 17(10): 1199-205, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19572121

RESUMEN

In spite of improvements in cementing technique, migration of tibial component remains a problem in total knee arthroplasty. This study compares the primary stability of tibial components using two different cementing techniques with roentgen stereophotogrammetric analysis (RSA) in vitro. A total of 20 tibia specimens were matched into two groups, 10 specimens per group. Cementing technique was randomized to each group. In the first group only the base and in the second group the base and stem were cemented. The implants and the tibial metaphysis were marked with markers for the RSA analysis. All specimens were tested with an axial load of 2,000 N for 1,000 and 10,000 cycles and RSA analysis was performed. Endpoints for radiosterometric analysis were maximum total point motion, maximum subsidence, lift off, rotation and translation along the x-, y-, and z-axes. After 1,000 and 10,000 cycles, no significant differences could be found, but two tibial components of the surface cementing group showed a migration of more than 2 mm defined as failure compared to six failed tibial components in the full cementing group (P = 0.068). This higher number of failed arthroplasties in the fully cemented prosthesis group demonstrates a disadvantageous load distribution in the tibia apophysis which can cause an early component loosening.


Asunto(s)
Artroplastia de Reemplazo de Rodilla/instrumentación , Cementación/métodos , Análisis de Falla de Equipo , Tibia , Anciano , Anciano de 80 o más Años , Cadáver , Femenino , Humanos , Prótesis de la Rodilla , Masculino , Fotogrametría
12.
ScientificWorldJournal ; 9: 313-9, 2009 Apr 28.
Artículo en Inglés | MEDLINE | ID: mdl-19412560

RESUMEN

Growth factors like bone morphogenetic protein 2 (BMP-2) and vascular endothelial growth factor (VEGF) play an important role in bone remodeling and fracture repair. Therefore, with respect to tissue engineering, an artificial graft should have no negative impact on the expression of these factors. In this context, the aim of this study was to analyze the impact of poly(L-lactic acid) (PLLA) nanofibers on VEGF and BMP-2 gene expression during the time course of human mesenchymal stem cell (hMSC) differentiation towards osteoblasts. PLLA matrices were seeded with hMSCs and cultivated over a period of 22 days under growth and osteoinductive conditions, and analyzed during the course of culture, with respect to gene expression of VEGF and BMP-2. Furthermore, BMP-2-enwoven PLLA nanofibers were used in order to elucidate whether initial down-regulation of growth factor expression could be compensated. Although there was a great interpatient variability with respect to the expression of VEGF and BMP-2, PLLA nanofibers tend to result in a down-regulation in BMP-2 expression during the early phase of cultivation. This effect was diminished in the case of VEGF gene expression. The initial down-regulation was overcome when BMP-2 was directly incorporated into the PLLA nanofibers by electrospinning. Furthermore, the incorporation of BMP-2 into the PLLA nanofibers resulted in an increase in VEGF gene expression. Summarized, the results indicate that the PLLA nanofibers have little effect on growth factor production. An enhancement in gene expression of BMP-2 and VEGF can be achieved by an incorporation of BMP-2 into the PLLA nanofibers.


Asunto(s)
Proteína Morfogenética Ósea 2/biosíntesis , Ácido Láctico/farmacología , Células Madre Mesenquimatosas/metabolismo , Polímeros/farmacología , Factor A de Crecimiento Endotelial Vascular/biosíntesis , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/genética , Regulación hacia Abajo , Expresión Génica/efectos de los fármacos , Humanos , Células Madre Mesenquimatosas/citología , Células Madre Mesenquimatosas/efectos de los fármacos , Nanoestructuras , Poliésteres , Ingeniería de Tejidos
13.
Diabetes Care ; 13(5): 483-7, 1990 May.
Artículo en Inglés | MEDLINE | ID: mdl-2351025

RESUMEN

Recent studies suggest that gestational diabetes mellitus (GDM) is underdiagnosed. To test this hypothesis, we examined the relationship of perinatal complications to glucose tolerance during the third trimester. Our population consisted of 287 women evaluated at approximately 28 wk gestation who had normal fasting (less than 5.9 mM) and 2-h (less than 9.2 mM plasma glucose) levels after a 100-g glucose load. Glycosylated hemoglobin and glycosylated plasma protein were also measured. Study subjects were stratified into three groups based on 2-h plasma glucose values: group 1 (n = 59) less than 5.6 mM, group 2 (n = 112) 5.6-6.0 mM, and group 3 (n = 116) 6.7-9.2 mM. There were statistically significant but low correlations (r less than 0.20) between 2-h plasma glucose levels and mother's age, body mass index, infant weights, and Apgar scores. There was a significant increasing trend in the proportion of overweight and obese women from groups 1 to 3 (P less than 0.02). There was also a significant trend toward higher birth weights (P = 0.013) and larger proportions of large for gestational age (LGA) babies (P = 0.02) from groups 1 to 3, and women with LGA infants showed higher fasting and 2-h plasma glucose levels than women with non-LGA infants (P = 0.032). However, there was no significant difference in perinatal complications or infant morbidity or mortality between groups. Percentage of glycosylated hemoglobin or glycosylated plasma protein did not differ between groups.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Glucemia/metabolismo , Prueba de Tolerancia a la Glucosa , Complicaciones del Embarazo/sangre , Adulto , Peso al Nacer , Peso Corporal , Ayuno , Femenino , Hemoglobina Glucada/análisis , Humanos , Recién Nacido , Embarazo , Resultado del Embarazo
14.
Hum Immunol ; 29(2): 117-30, 1990 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1701168

RESUMEN

This study was undertaken to resolve a positive mixed lymphocyte reaction between HLA-ABC identical, HLA-D different siblings. Three CD3+ CD4+ CD8- alloreactive T-lymphocyte clones, called 2/6, 7/1, and 7/2, were generated and extensively studied. Proliferation of 2/6 cells and 7/2 cells was blocked by anti-DQ monoclonal antibodies (mAbs), whereas anti-DR and DP were not effective. Stimulation of 7/1 cells was inhibited by anti-DR, but not by anti-DQ and DP mAbs. Testing on a well-characterized panel of reference B-lymphoblastoid cell lines showed that the DQ-specific clones 2/6 and 7/2 were able to proliferate upon stimulation by cells carrying the DQw7 and DQw8 but not the DQw9 subtype of DQw3. Clone 7/1 was proliferative towards cells expressing DRw11.1 but not towards DRw11.2- or DRw12-positive cells. Moreover, this clone detected determinants present on some DRw8 cells. Correlation of the reactivity of clone 7/1 with available sequence data suggests that amino acids 67, 71, and 86 of DR beta 1 molecules played a crucial role in forming the epitope recognized by this clone. In contrast, sharing of T-cell epitopes between DQw7 and DQw8 subtypes was not inferable from specific amino acid residues. The implication of these findings for T-cell allorecognition is discussed.


Asunto(s)
Antígenos HLA-DQ/genética , Antígeno HLA-DR5/genética , Linfocitos T/inmunología , Secuencia de Aminoácidos , Anticuerpos Monoclonales/inmunología , Células Clonales/inmunología , Intercambio Genético , Epítopos/inmunología , Antígenos HLA-B/genética , Antígenos HLA-DQ/clasificación , Antígeno HLA-DR5/clasificación , Humanos , Prueba de Cultivo Mixto de Linfocitos , Datos de Secuencia Molecular , Homología de Secuencia de Ácido Nucleico
15.
Z Orthop Unfall ; 152(3): 234-40, 2014 Jun.
Artículo en Alemán | MEDLINE | ID: mdl-24960091

RESUMEN

BACKGROUND: Since 1985 the hips of the newborns have been sonographically screened at the University Hospital Marburg by staff of the Orthopaedic Department. This study was conducted to collect data on the local incidence of DDH (developmental dysplasia of the hip). Moreover, the diagnostic findings were checked critically to detect weak points. Another aim was to analyse the influence of investigators' experience on the treatment recommendation. MATERIAL AND METHODS: In a retrospective study, 18 247 hip sonograms in a treatment period from 1985 to 2009 were analysed. The following parameters were evaluated: perinatal incidents (e.g., breech presentation, Caesarean section, premature delivery), orthopaedic findings (e.g., club foot, limitation of hip abduction). Bony roof, superior bony rim and cartilaginous roof were analysed; α- and ß-angles and hip type according to Graf were documented. Comparisons between variables were calculated by means of adequate statistic tests. χ(2)-values and coefficients of correlation were used to detect significance. RESULTS: All in all 55 physicians of our Orthopaedic Department conducted 350 measurements on average (min. 1; max. 1993). Accuracy of documentation improved over time. In particular in the beginning of the screening, the hip angles according to Graf were not completely determined and sonograms were classified by "visual diagnosis". The ß-angle was not measured at the outset. In the course of time we measured a decrease of the diagnosis hip type II a according to Graf. In the years 1985-1989 more than 40 % of the hips were described as physiologically immature. We evaluated a numerical regression of hip type II a to 16 % in time period 1990-1994 and 9 % in time period 2005-2009. There was a significant correlation between breech presentation and decentering and eccentric hips. Inexperienced physicians recommend more often therapeutic interventions (p ≤ 0.01). Treatment of hip type II a according to Graf was inconsistent over time. CONCLUSION: This study demonstrates the necessity of standardised hip sonography. Treatment according to measured hip type should be concise. Training programmes both for instructors and medical assistant staff is mandatory. "Bedside teaching" is not constructive.


Asunto(s)
Presentación de Nalgas/epidemiología , Cesárea/estadística & datos numéricos , Luxación Congénita de la Cadera/diagnóstico por imagen , Luxación Congénita de la Cadera/epidemiología , Tamizaje Neonatal , Pautas de la Práctica en Medicina/estadística & datos numéricos , Ultrasonografía/estadística & datos numéricos , Presentación de Nalgas/diagnóstico por imagen , Manejo de Caso/estadística & datos numéricos , Comorbilidad , Femenino , Alemania/epidemiología , Luxación Congénita de la Cadera/terapia , Humanos , Incidencia , Recién Nacido , Masculino , Tamizaje Masivo/estadística & datos numéricos , Embarazo , Prevalencia , Factores de Riesgo
16.
Orthop Traumatol Surg Res ; 98(7): 765-72, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23098773

RESUMEN

BACKGROUND: The aim of this study is the presentation of the polyaxial locking NCB-plate in the treatment of femoral fractures, especially in elderly patients and in proximity of a prosthetic implant. The reduction and fixation of these fractures is a challenging surgical procedure with high complication rates reported up to 40%. PATIENTS AND METHODS: A total of 72 patients with femoral fractures had polyaxial locking plate osteosynthesis. Indications included fractures of the shaft and around an implant. Concerning surgical procedures, three different standardized techniques were performed: (1) minimally invasive with percutaneous distal insertion using a targeting device; (2) mini-open with additional cerclage wire via the same approach and (3) a conventional open reduction and internal fixation. Data collection included intraoperative data and early complications at 6, 24 and 52 weeks. Fifty-two patients had an implant or prosthesis in situ. Thirty-three patients were treated by technique (1), 32 patients had mini-open surgery and seven patients conventional open surgery. RESULTS: Thirty-nine patients attended clinical follow-up after 52 weeks. Twenty-two patients were interviewed by telephone, two were untraceable and nine patients had died. Bony consolidation without secondary loss of reduction was confirmed after 52 weeks in all patients but two. Plate breakage occurred in these two at 25 and 31 weeks after surgery due to non-union. Implant related complications (17% in total) lead to surgical revision in five other cases: two deep wound infections as well as three minor revisions. When itemizing complications according to surgical technique used, most major complications occurred following open surgery. CONCLUSION: The availability of polyaxial locking implants widened the range of indications for plate fixation in femoral fractures. The advantages of the polyaxial locking implant combined with minimally invasive surgical technique contribute to successful management of this population category. Early revision rate is noticeably lower compared to similar procedures. LEVEL OF EVIDENCE: IV retrospective series.


Asunto(s)
Placas Óseas , Hilos Ortopédicos , Fracturas del Fémur/cirugía , Fijación de Fractura/instrumentación , Fracturas Periprotésicas/cirugía , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Femenino , Fracturas del Fémur/diagnóstico por imagen , Humanos , Prótesis Articulares , Masculino , Persona de Mediana Edad , Fracturas Periprotésicas/diagnóstico por imagen , Radiografía , Reoperación , Resultado del Tratamiento
17.
Z Orthop Unfall ; 150(2): 163-9, 2012 Apr.
Artículo en Alemán | MEDLINE | ID: mdl-22498840

RESUMEN

AIM: Two different measurement techniques of ultrasonograms of the infant hip were evaluated with respect to reproducibility of the Graf classification and variation of α- and ß-angles. MATERIAL AND METHODS: In a cross-sectional, blinded study, the hips of 207 consecutive newborn babies (101 male; 106 female) were sonographically screened at an average of 2.64 days after birth. Each hip was measured twice by three investigators with different levels of experience - a paediatric orthopaedic surgeon, a senior surgeon and a trained medical student. A mobile ultrasound system (SONOLINE G60S®, Siemens, Erlangen, Germany), equipped with a 7.5 MHz linear transducer, was used. Both hip joints were measured twice by all three investigators. The measurement was performed 6-8 weeks later in a blinded manner. The sonograms were initially printed out on high-quality paper strips and measured by pencil, ruler and goniometer. Finally, each investigator evaluated the same sonograms computer-assisted, using the trackball and dashboard of the ultrasound system. RESULTS: Concerning intraobserver reliability, we observed a significant reduction of variation both for α- and ß-angles in favour of the classic measurement on printed strips (p < 0.05). The interobserver calculation also detected a trend for higher angle variation when the angles were measured electronically. The reproducibility of Graf classification was not influenced by the kind of measurement technique. The outcome was not affected by investigator's level of experience (p > 0.05). CONCLUSIONS: This study demonstrated considerable advantages for the classic measurement of paediatric hip ultrasonograms with pencil and goniometer on printed paper strips compared to computer-aided measurement concerning variation of α- and ß-angles.


Asunto(s)
Artrometría Articular/instrumentación , Articulación de la Cadera/diagnóstico por imagen , Articulación de la Cadera/fisiología , Interpretación de Imagen Asistida por Computador/instrumentación , Rango del Movimiento Articular/fisiología , Ultrasonografía/instrumentación , Artrometría Articular/métodos , Diseño de Equipo , Análisis de Falla de Equipo , Humanos , Interpretación de Imagen Asistida por Computador/métodos , Recién Nacido , Masculino , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Método Simple Ciego
18.
Open Orthop J ; 5: 177-80, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21633723

RESUMEN

OBJECTIVE: To evaluate the expression of VEGF by chondrocytes of hyaline cartilage during the course of osteoarthritis (OA). METHODS: In 12 white New Zealand rabbits the anterior cruciate ligament (ACL) was resected to create an anterior instability of the knee. In 12 control rabbits only a sham operation without resection of the ACL was done. Four animals of each group were killed at 3, 6, and 12 weeks. The load bearing area was evaluated histologically according to Mankin and by immunostaining for VEGF. RESULTS: In the experimental group, histological grades of OA showed a positive linear correlation with the time after surgery. Immunostaining showed an increased expression of VEGF in the control group after 3 weeks, which dropped to normal after 6 weeks. There was no difference in the progression of OA between control and experimental groups after 3 weeks, but a significant difference was seen after 6 (p=0,01) and 12 (p=0,05) weeks. A significant positive correlation between VEGF expression and the histological grade of OA was found (r = 0.767; p<0.01). CONCLUSIONS: An increase of VEGF expressing chondrocytes occurs during time course of OA.

19.
Sportverletz Sportschaden ; 25(3): 173-8, 2011 Sep.
Artículo en Alemán | MEDLINE | ID: mdl-21922440

RESUMEN

AIM: Femoroacetabular impingement (FAI) is a recently proposed mechanical concept for the development of osteoarthritis of the hip. Aim of this nationwide survey is the description of the current status of diagnostics and therapy of FAI in Germany. MATERIAL AND METHODS: All orthopedic and traumatological hospitals listed in the "list of German hospitals 2006" were invited via e-mail to take part in this anonymous survey. RESULTS: The questionnaire was answered by 682 departments (50.5 %). 98 (14.3 %) of these departments treated FAI in 2007. CONCLUSION: In Germany, diagnostics and treatment of FAI were performed inconsistently in a small number of specialized hospitals.


Asunto(s)
Pinzamiento Femoroacetabular/diagnóstico , Pinzamiento Femoroacetabular/cirugía , Adulto , Anciano , Artroscopía , Estudios Transversales , Femenino , Pinzamiento Femoroacetabular/etiología , Alemania , Encuestas Epidemiológicas , Hospitalización/estadística & datos numéricos , Humanos , Internet , Masculino , Persona de Mediana Edad , Procedimientos Quirúrgicos Mínimamente Invasivos , Osteoartritis de la Cadera/diagnóstico , Osteoartritis de la Cadera/epidemiología , Osteoartritis de la Cadera/cirugía , Cuidados Posoperatorios , Encuestas y Cuestionarios
20.
Z Orthop Unfall ; 148(1): 83-9, 2010 Jan.
Artículo en Alemán | MEDLINE | ID: mdl-20135587

RESUMEN

AIM: The aim of the study was to survey the current state of the conservative and operative treatment of anterior shoulder instability and its rehabilitation in German hospitals. METHODS: A previously evaluated online questionnaire was sent out to all German hospitals with orthopaedic or trauma surgery departments. The Federal Statistical Office's hospital list was the basis for the selection of hospitals. The questions referred to the year 2007. The survey, including 3 reminders, was conducted over 3 months. The questionnaire consisted of 6 response categories: always (100%), almost always (99-81%), predominantly (80-51%), rarely (50-21%), almost never (20-1%) and never (0%). RESULTS: The response rate was 41% and 67% of these had carried out shoulder stabilisations. In total, 99.2% of the 67% were evaluable. The proportion of shoulder surgery was 8.4% of the total number of operations. Shoulder stabilisations represented 10.6% of these operations. A specialised shoulder department existed in 22.9%. Conservative treatment was carried out with an immobilisation of the arm "predominantly", "almost always" and "always" for internal rotation in 70.8% and in 23.4% for external rotation. The shoulders were "predominantly", "almost always" and "always" stabilised in an arthroscopic technique in 68.2% and in an open one in 31.8% of the clinics. With 92.9%, the Bankart repair was the most common operation. Shoulder instability was principally treated with the arthroscopic technique, regardless of the care level and department and is considered the best surgical technique. Physiotherapy was prescribed "always" and "almost always" in 99.3%. The rate of reluxation after conservative treatment was estimated at 35.5%, after operative open anterior shoulder stabilisation at 9.1% and after arthroscopic shoulder stabilization at 10.6%. Nevertheless, 49.4% of respondents expected the best results after arthroscopic treatment. Participants, who mainly applied the arthroscopic technique, expected a lower rate of reluxation in comparison to other techniques (p<0.001). CONCLUSION: The operative shoulder stabilisation is most frequently carried out as arthroscopic Bankart repair. A standardised, subsequent treatment is well established.


Asunto(s)
Artroscopía/estadística & datos numéricos , Inestabilidad de la Articulación/cirugía , Complicaciones Posoperatorias/rehabilitación , Luxación del Hombro/cirugía , Terapia Combinada , Recolección de Datos , Alemania , Tamaño de las Instituciones de Salud , Capacidad de Camas en Hospitales/estadística & datos numéricos , Humanos , Inestabilidad de la Articulación/diagnóstico , Evaluación de Procesos y Resultados en Atención de Salud/estadística & datos numéricos , Reoperación/estadística & datos numéricos , Prevención Secundaria , Luxación del Hombro/diagnóstico , Servicio de Cirugía en Hospital/estadística & datos numéricos , Encuestas y Cuestionarios , Revisión de Utilización de Recursos/estadística & datos numéricos
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