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3.
Front Psychiatry ; 10: 762, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31736795

RESUMEN

Violent behavior in correctional facilities is common and differs substantially in type, target, implication, and trigger. Research on frequency and characteristics of violent behavior in correctional facilities and psychiatric hospitals is limited. Results from recent research suggest that comorbidity of severe mental disorder, personality disorder, and diagnosis of substance abuse is related to a higher risk of violent behavior. In the Berlin prison hospital, a database was created to collect data from all violent incidences (n=210) between 1997 and 2006 and between 2010 and 2016. In a retrospective, case-control study, we analyzed specific socioeconomic data and psychiatric diagnosis and compared the group of prisoners with violent behavior with randomly selected prisoners of the same department without violent behavior (n = 210). Diagnosis of schizophrenia, non-German nationality, no use of an interpreter, no children, and no previous sentence remained significantly associated with the dependent variable violent behavior. There were no significant differences regarding age and legal statuses. Practical implications for clinical work are discussed.

4.
Front Psychiatry ; 10: 961, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-32009992

RESUMEN

[This corrects the article DOI: 10.3389/fpsyt.2019.00762.].

5.
Allergy ; 73(1): 93-105, 2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28670695

RESUMEN

BACKGROUND: Glycoproteins and glycolipids of some mammalian species contain the disaccharide galactosyl-α-(1,3)-galactose (α-Gal). It is known that α-Gal is immunogenic in humans and causes glycan-specific IgG and also IgE responses with clinical relevance. α-Gal is part of the IgE-reactive monoclonal therapeutic antibody cetuximab (CTX) and is associated with delayed anaphylaxis to red meat. In this study, different α-Gal-containing analytes are examined in singleplex and multiplex assays to resolve individual sensitization patterns with IgE against α-Gal. METHODS: Three serum groups, α-Gal-associated meat allergy (MA) patients, idiopathic anaphylaxis (IA) patients with suspected MA, and non-meat-allergic healthy control individuals (HC), were analyzed via singleplex allergy diagnostics and a newly established immunoblot diagnostic system. The new dot blot detection system resolved individual IgE sensitization profiles for α-Gal-containing analytes CTX, bovine thyroglobulin (Bos d TG), and human serum albumin (HSA)-conjugated α-Gal. RESULTS: Singleplex allergy diagnostics using the α-Gal analytes CTX and Bos d TG confirms the history of MA patients in 91% and 88% of the cases, respectively. A novel dot blot-based assay system for the detection of IgE against α-Gal reveals individual IgE sensitization profiles for α-Gal-containing analytes. An α-Gal-associated IgE cross-reactivity profile (IgE against CTX, Bos d TG, and HSA-α-Gal) was identified, which is associated with MA. CONCLUSIONS: Detection of individual sensitization patterns with different α-Gal-containing analytes provides the basis for an individual allergy diagnosis for α-Gal-sensitized patients. Higher amounts of α-Gal in pork and beef innards compared to muscle meat as indicated by a higher staining intensity are a plausible explanation for the difference in allergic symptom severity.


Asunto(s)
Alérgenos/inmunología , Hipersensibilidad a los Alimentos/diagnóstico , Hipersensibilidad a los Alimentos/inmunología , Galactosa/inmunología , Inmunoglobulina E/inmunología , Carne/efectos adversos , Adulto , Anciano , Anafilaxia/diagnóstico , Anafilaxia/inmunología , Estudios de Casos y Controles , Reacciones Cruzadas/inmunología , Femenino , Galactosa/química , Humanos , Inmunoquímica , Masculino , Persona de Mediana Edad , Carne Roja/efectos adversos , Adulto Joven
6.
Schmerz ; 31(6): 580-593, 2017 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-28660417

RESUMEN

BACKGROUND: Pain intensity (PI) is a common outcome parameter in effectiveness studies on interdisciplinary multimodal pain therapy (IMPT), despite the fact that IMPT highlights dealing with rather than reducing chronic pain. Moreover, the measurement of pain intensity as a highly subjective experience is problematic. Patient participation is absolutely essential to examine the relevance of PI as a criterion of treatment success as well as to select/develop suitable measurement methods. METHOD: A qualitative multicenter study was conducted using focus groups with 69 patients (18-77 years; 80% female) at four different IMPT centers in Germany to discuss pain intensity as a therapy outcome parameter in IMPT, as well as the interpretability and feasibility of common measurement methods. RESULTS: The discussions emphasized that PI is a relevant, but not the primary, outcome in IMPT for patients. Patients' statements also demonstrate that there are some problems in measuring PI, for instance with regard to pain attacks. CONCLUSIONS: The focus group discussions suggested that, due to the highly subjective nature of PI, as well as (verbal) inaccuracies and a lack of standardization in common instruments, the measurement of pain intensity is a challenging task. These limitations should be taken into account in future studies.


Asunto(s)
Dolor Crónico , Manejo del Dolor , Dimensión del Dolor , Adolescente , Adulto , Anciano , Dolor Crónico/terapia , Terapia Combinada , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Resultado del Tratamiento , Adulto Joven
7.
Sci Rep ; 6: 36047, 2016 10 26.
Artículo en Inglés | MEDLINE | ID: mdl-27782196

RESUMEN

Fe-based superconductors (FBS) present a large variety of compounds whose properties are affected to different extents by their crystal structures. Amongst them, the REFeAs(O,F) (RE1111, RE being a rare-earth element) is the family with the highest critical temperature Tc but also with a large anisotropy and Josephson vortices as demonstrated in the flux-flow regime in Sm1111 (Tc ∼ 55 K). Here we focus on the pinning properties of the lower-Tc Nd1111 in the flux-creep regime. We demonstrate that for H//c critical current density Jc at high temperatures is dominated by point-defect pinning centres, whereas at low temperatures surface pinning by planar defects parallel to the c-axis and vortex shearing prevail. When the field approaches the ab-planes, two different regimes are observed at low temperatures as a consequence of the transition between 3D Abrikosov and 2D Josephson vortices: one is determined by the formation of a vortex-staircase structure and one by lock-in of vortices parallel to the layers. This is the first study on FBS showing this behaviour in the full temperature, field, and angular range and demonstrating that, despite the lower Tc and anisotropy of Nd1111 with respect to Sm1111, this compound is substantially affected by intrinsic pinning generating a strong ab-peak in Jc.

8.
Nanoscale Res Lett ; 11(1): 58, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26842791

RESUMEN

Quantitative description of charge transport across tunneling and break-junction devices with novel superconductors encounters some problems not present or not as severe for traditional superconducting materials. In this work, we explain unexpected features in related transport characteristics as an effect of a degraded nanoscaled sheath at the superconductor surface. A model capturing the main aspects of the ballistic charge transport across hybrid superconducting structures with normally conducting nanometer-thick interlayers is proposed. The calculations are based on a scattering formalism taking into account Andreev electron-into-hole (and inverse) reflections at normal metal-superconductor interfaces as well as transmission and backscattering events in insulating barriers between the electrodes. Current-voltage characteristics of such devices exhibit a rich diversity of anomalous (from the viewpoint of the standard theory) features, in particular shift of differential-conductance maxima at gap voltages to lower positions and appearance of well-defined dips instead expected coherence peaks. We compare our results with related experimental data.

9.
Br J Pharmacol ; 166(7): 2049-59, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22372570

RESUMEN

BACKGROUND AND PURPOSE: Airway remodelling is a consequence of long-term inflammation and MAPKs are key signalling molecules that drive pro-inflammatory pathways. The endogenous MAPK deactivator--MAPK phosphatase 1 (MKP-1)--is a critical negative regulator of the myriad pro-inflammatory pathways activated by MAPKs in the airway. EXPERIMENTAL APPROACH: Herein we investigated the molecular mechanisms responsible for the upregulation of MKP-1 in airway smooth muscle (ASM) by the corticosteroid dexamethasone and the ß2-agonist formoterol, added alone and in combination. KEY RESULTS: MKP-1 is a corticosteroid-inducible gene whose expression is enhanced by long-acting ß2-agonists in an additive manner. Formoterol induced MKP-1 expression via the ß2-adrenoceptor and we provide the first direct evidence (utilizing overexpression of PKIα, a highly selective PKA inhibitor) to show that PKA mediates ß2-agonist-induced MKP-1 upregulation. Dexamethasone activated MKP-1 transcription in ASM cells via a cis-acting corticosteroid-responsive region located between -1380 and -1266 bp of the MKP-1 promoter. While the 3'-untranslated region of MKP-1 contains adenylate + uridylate elements responsible for regulation at the post-transcriptional level, actinomycin D chase experiments revealed that there was no increase in MKP-1 mRNA stability in the presence of dexamethasone, formoterol, alone or in combination. Rather, there was an additive effect of the asthma therapeutics on MKP-1 transcription. CONCLUSIONS AND IMPLICATIONS: Taken together, these studies allow us a greater understanding of the molecular basis of MKP-1 regulation by corticosteroids and ß2-agonists and this new knowledge may lead to elucidation of optimized corticosteroid-sparing therapies in the future.


Asunto(s)
Corticoesteroides/farmacología , Agonistas de Receptores Adrenérgicos beta 2/farmacología , Dexametasona/farmacología , Fosfatasa 1 de Especificidad Dual/biosíntesis , Etanolaminas/farmacología , Fosfatasa 1 de Especificidad Dual/genética , Fumarato de Formoterol , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Humanos , ARN Mensajero/biosíntesis , Células Tumorales Cultivadas , Regulación hacia Arriba
10.
Eur Respir J ; 38(6): 1444-52, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21719482

RESUMEN

Airway smooth muscle cells (ASMCs) secrete eotaxin and RANTES (regulated on activation, normal T-cell expressed and secreted) in response to tumour necrosis factor (TNF)-α, which is inhibited by the nuclear factor (NF)-κB inhibitor dimethylfumarate (DMF). NF-κB/IκB (inhibitor of NF-κB) glutathionylation and changes in chromatin remodelling can inhibit NF-κB activity. In this study, we determined whether NF-κB/IκB glutathionylation and reduced histone H3 phosphorylation might underlie the inhibitory effect of DMF on NF-κB activity, and eotaxin and RANTES secretion. Primary human ASMCs were treated with DMF, diamide and/or glutathione (GSH) ethylester (OEt) prior to TNF-α stimulation and were subsequently analysed by ELISA, electrophoretic mobility shift assay, immunofluorescence, co-immunoprecipitation or immunoblotting. DMF reduced intracellular GSH and induced IκBα glutathionylation (IκBα-SSG), which inhibited IκBα degradation, NF-κB p65 nuclear entry and NF-κB/DNA binding. In addition, DMF inhibited the phosphorylation of histone H3, which was possibly mediated by the inhibitory effect of DMF on mitogen- and stress-activated protein kinase (MSK)-1. However, p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase MAPK and MAPK phosphatase-1, upstream of MSK-1, were not inhibited by DMF. Importantly, DMF-mediated effects on NF-κB, histone H3, eotaxin and RANTES were reversed by addition of GSH-OEt. Our data suggest that DMF inhibits NF-κB-dependent eotaxin and RANTES secretion by reduction of GSH with subsequent induction of IκBα-SSG and inhibition of histone H3 phosphorylation. Our findings offer new potential drug targets to reduce airway inflammation in asthma.


Asunto(s)
Quimiocina CCL5/antagonistas & inhibidores , Quimiocinas CC/antagonistas & inhibidores , Glutatión/metabolismo , Histonas/metabolismo , Proteínas I-kappa B/metabolismo , Miocitos del Músculo Liso/metabolismo , Adulto , Anciano , Células Cultivadas , Quimiocina CCL5/metabolismo , Quimiocinas CC/metabolismo , Diamida/farmacología , Dimetilfumarato , Fumaratos/farmacología , Humanos , Masculino , Persona de Mediana Edad , Inhibidor NF-kappaB alfa , FN-kappa B/antagonistas & inhibidores , Fosforilación , Pruebas de Función Respiratoria , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Reactivos de Sulfhidrilo/farmacología , Factor de Necrosis Tumoral alfa/farmacología
11.
Rev Sci Instrum ; 82(1): 013302, 2011 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21280820

RESUMEN

This paper presents nondestructive dark current measurements of tera electron volt energy superconducting linear accelerator cavities. The measurements were carried out in an extremely noisy accelerator environment using a low temperature dc superconducting quantum interference device based cryogenic current comparator. The overall current sensitivity under these rough conditions was measured to be 0.2 nA/Hz(1/2), which enables the detection of dark currents of 5 nA.

12.
Curr Eye Res ; 35(10): 900-8, 2010 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-20858111

RESUMEN

PURPOSE: Antibodies against heat shock proteins have been identified in sera of human glaucoma patients in several studies and immunization with heat shock protein 60 (HSP 60) causes retinal ganglion cell (RGC) loss in an animal model of experimental autoimmune glaucoma. The aim of this study was to observe the time course of increased anti-retina antibody appearance in the serum and characterize the identification of prominent autoantibodies that accompany HSP 60 immunization in a rat model of experimental autoimmune glaucoma. METHODS: Eight weeks after immunization with HSP 60 retinal flatmounts were prepared and RGCs were counted in eight predefined areas and compared to controls. Serum collected before, as well as four and eight weeks after, immunization was used to detect antibody patterns against bovine retinal antigens using Western blotting techniques. These patterns were analyzed by multivariate statistical methods. Autoantibodies that were prominently increased were further identified through mass spectrometry. Intraocular pressure was measured throughout the study. RESULTS: After eight weeks, animals immunized with HSP 60 showed significant RGC loss of retinal flatmounts (P = 0.02), which was intraocular pressure independent. Early changes in antibody profiles, many of them significant upregulations, were detected. Antigens with significantly upregulated antibody reactivity after four weeks were identified as histone H2B type 1, S-arrestin, glial fibrillary acidic protein, vimentin, and heat shock protein 60. These upregulated autoantibodies returned to normal levels four weeks following their initial upregulation. Antibodies against retinaldehyde binding protein 1 on the other hand became upregulated after eight weeks. CONCLUSION: This is the first study to identify the appearance and disappearance of retinal autoantibodies in the serum of rats at several time-points following their initial upregulation in response to HSP 60 immunization in a model of experimental autoimmune glaucoma.


Asunto(s)
Autoanticuerpos/sangre , Enfermedades Autoinmunes/inmunología , Chaperonina 60/inmunología , Glaucoma/inmunología , Inmunización , Animales , Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/patología , Regulación hacia Abajo , Glaucoma/sangre , Glaucoma/patología , Masculino , Ratas , Ratas Endogámicas Lew , Retina/inmunología , Células Ganglionares de la Retina/patología , Factores de Tiempo , Regulación hacia Arriba
13.
Am J Physiol Lung Cell Mol Physiol ; 297(2): L326-39, 2009 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-19465513

RESUMEN

The antipsoriatic dimethylfumarate (DMF) has been anecdotically reported to reduce asthma symptoms and to improve quality of life of asthma patients. DMF decreases the expression of proinflammatory mediators by inhibiting the transcription factor NF-kappaB and might therefore be of interest for the therapy of inflammatory lung diseases. In this study, we determined the effect of DMF on platelet-derived growth factor (PDGF)-BB- and TNFalpha-induced asthma-relevant cytokines and NF-kappaB activation by primary human asthmatic and nonasthmatic airway smooth muscle cells (ASMC). Confluent nonasthmatic and asthmatic ASMC were incubated with DMF (0.1-100 microM) and/or dexamethasone (0.0001-0.1 microM), NF-kappaB p65 siRNA (100 nM), the NF-kappaB inhibitor helenalin (1 microM) before stimulation with PDGF-BB or TNFalpha (10 ng/ml). Cytokine release was measured by ELISA. NF-kappaB, mitogen and stress-activated kinase (MSK-1), and CREB activation was determined by immunoblotting and EMSA. TNFalpha-induced eotaxin, RANTES, and IL-6 as well as PDGF-BB-induced IL-6 expression was inhibited by DMF and by dexamethasone from asthmatic and nonasthmatic ASMC, but the combination of both drugs showed no glucocorticoid sparing effect in either of the two groups. NF-kappaB p65 siRNA and/or the NF-kappaB inhibitor helenalin reduced PDGF-BB- and TNFalpha-induced cytokine expression, suggesting the involvement of NF-kappaB signaling. DMF inhibited TNFalpha-induced NF-kappaB p65 phosphorylation, NF-kappaB nuclear entry, and NF-kappaB-DNA complex formation, whereas PDGF-BB appeared not to activate NF-kappaB within 60 min. Both stimuli induced the phosphorylation of MSK-1, NF-kappaB p65 at Ser276, and CREB, and all were inhibited by DMF. These data suggest that DMF downregulates cytokine secretion not only by inhibiting NF-kappaB but a wider range of NF-kappaB-linked signaling proteins, which may explain its potential beneficial effect in asthma.


Asunto(s)
Bronquios/citología , Citocinas/metabolismo , Fumaratos/farmacología , Inmunosupresores/farmacología , Miocitos del Músculo Liso/efectos de los fármacos , Neumonía/tratamiento farmacológico , Factor de Transcripción ReIA/metabolismo , Antiinflamatorios no Esteroideos/farmacología , Becaplermina , Bronquios/inmunología , Células Cultivadas , Quimiocina CCL11/metabolismo , Quimiocina CCL5/metabolismo , Enfermedad Crónica , Proteína de Unión a Elemento de Respuesta al AMP Cíclico/metabolismo , Dexametasona/farmacología , Dimetilfumarato , Inhibidores Enzimáticos/farmacología , Glucocorticoides/farmacología , Humanos , Proteínas I-kappa B/metabolismo , Interleucina-6/metabolismo , Isoquinolinas/farmacología , Miocitos del Músculo Liso/citología , Miocitos del Músculo Liso/inmunología , Inhibidor NF-kappaB alfa , Factor de Crecimiento Derivado de Plaquetas/metabolismo , Neumonía/inmunología , Neumonía/metabolismo , Proteínas Proto-Oncogénicas c-sis , ARN Interferente Pequeño , Proteínas Quinasas S6 Ribosómicas 90-kDa/metabolismo , Sesquiterpenos/farmacología , Sesquiterpenos de Guayano , Sulfonamidas/farmacología , Factor de Transcripción ReIA/genética , Factor de Necrosis Tumoral alfa/metabolismo
14.
Neural Netw ; 20(5): 646-51, 2007 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17275256

RESUMEN

Nucleosides in human urine are of interest as a biochemical marker for cancer, acquired immune deficiency syndrome (AIDS) and the whole-body turnover of RNAs. A reversed-phase high-performance liquid chromatography (RP-HPLC) method with photodiode-array detection was used to quantitatively analyze urinary normal and modified nucleosides. 55 persons with malignant tumors of various types, 13 persons with benign tumors and 41 healthy controls were investigated within a clinical intervention study. Artificial neural networks (ANN) have been used as a practical pattern recognition tool to distinguish cancer patients from healthy persons. Using a multilayer perceptron (MPL), a specificity of 85%, and a sensitivity of 97% in differentiation between tumor patients and healthy persons was achieved. The differentiation between benign and malignant tumors had a sensitivity of 60% and a specificity of 84%. These results verify the usefulness of ANN and the RP-HPLC method for tumor recognition in agreement with existing studies.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Neoplasias/diagnóstico , Neoplasias/orina , Redes Neurales de la Computación , Nucleósidos/orina , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reconocimiento de Normas Patrones Automatizadas/métodos
15.
Br J Cancer ; 94(11): 1726-33, 2006 Jun 05.
Artículo en Inglés | MEDLINE | ID: mdl-16685264

RESUMEN

Modified nucleosides, regarded as indicators for the whole-body turnover of RNAs, are excreted in abnormal amounts in the urine of patients with malignancies. To test their usefulness as tumour markers and to compare them with the conventional tumour markers, fractionated urine samples were analysed using chromatography. The excretion patterns of nucleosides of 68 cancer patients with malignant and benign tumours and 41 healthy controls have been studied. Significant elevations in the total sum and the concentrations of at least three (or four) of indicator nucleosides cytidine, pseudouridine, 2-pyridone-5-carboxamide-N1-ribofuranoside, N2,N2-dimethylguanine, 1-methylguanosine, 2-methylguanosine and 1-methyladenosine indicate a tumour with a sensitivity of 54% (77%) and a specificity of 86% (98%). Using an artificial neural network analysis, a sensitivity of 97% and a specificity of 85% were achieved in differentiating between tumour and control volunteers. The comparison with carcinoembryonic antigen, cancer antigen 15-3 und tissue polypeptide antigen indicates that urinary nucleosides may be useful tumour markers. This study suggests that the simultaneous determination of modified nucleosides and creatinine in urine samples of patients with cancer leads to an advantage to current methods and is a useful method to detect cancer early and to control the success of therapy.


Asunto(s)
Biomarcadores de Tumor/orina , Neoplasias/diagnóstico , Neoplasias/orina , Nucleósidos/orina , Adulto , Anciano , Cromatografía Líquida de Alta Presión , Creatinina/orina , Femenino , Humanos , Masculino , Persona de Mediana Edad , Metástasis de la Neoplasia , Estadificación de Neoplasias , Neoplasias/patología , Neoplasias/terapia , ARN Neoplásico/análisis
16.
Orthopade ; 33(8): 885-92, 2004 Aug.
Artículo en Alemán | MEDLINE | ID: mdl-15241590

RESUMEN

BACKGROUND: Multiresistant bacteria have become an important problem in prosthetic joint infections. Their frequent resistance against gentamicin, which is commonly used in antibiotic-loaded bone cements, makes a new prophylaxis necessary. METHODS: PMMA-cement was loaded with 1% nanoparticulate silver and its antibacterial activity tested in vitro against gentamicin-resistant MRSE and MRSA strains as well as being compared to the activity of plain and gentamicin-loaded bone cements. A quantitative elution testing was also done to study the potentially cytotoxic effects of NanoSilver cement. RESULTS: Unloaded and PMMA-cement loaded with 2% gentamicin did not exhibit any antibacterial activity against MRSE and MRSA. At 1%, NanoSilver cement completely inhibited the proliferation of MRSA and MRSE. NanoSilver bone cement did not show any significant differences compared to the non-toxic control group. CONCLUSIONS: If these promising in vitro results can be confirmed in vivo, NanoSilver bone cement may be of considerable value in total joint arthroplasty.


Asunto(s)
Antibacterianos/farmacología , Cementos para Huesos/farmacología , Cementos para Huesos/toxicidad , Supervivencia Celular/efectos de los fármacos , Resistencia a Múltiples Medicamentos , Resistencia a la Meticilina , Nanotecnología , Polimetil Metacrilato/farmacología , Staphylococcus aureus/efectos de los fármacos , Staphylococcus epidermidis/efectos de los fármacos , Animales , Antibacterianos/toxicidad , Línea Celular , Relación Dosis-Respuesta a Droga , Fibroblastos/efectos de los fármacos , Gentamicinas/farmacología , Gentamicinas/toxicidad , Ratones , Pruebas de Sensibilidad Microbiana , Microscopía Electrónica de Rastreo , Tamaño de la Partícula , Polimetil Metacrilato/toxicidad
17.
Z Orthop Ihre Grenzgeb ; 140(6): 603-10, 2002.
Artículo en Alemán | MEDLINE | ID: mdl-12476381

RESUMEN

INTRODUCTION: The use of vacuum mixing systems when mixing bone cement reduces its porosity and hereby significantly improves the features of the material. The currently available mixing systems are compared with regard to handling, mechanical properties and economical aspects. METHODS: In 8 vacuum mixing systems the handling, pump performance, system tightness, the used air volume, the filter efficiency, the remaining amounts in the mixing system and the porosity of the cements are shown in comparison. RESULTS: All vacuum mixing systems reduce the porosity of the cement in comparison to hand mixed cements significantly if used correctly. The individual examinations, though, show enormous differences, which can be of significance to the user in the individual choice of system and, depending on the individual circumstances, can influence the quality of the mixed cement. CONCLUSION: The results enable the user to choose and handle a vacuum mixing system which is optimally suitable for the individual circumstances in respect to the characteristics examined.


Asunto(s)
Artroplastia de Reemplazo/instrumentación , Cementos para Huesos/química , Metilmetacrilato/química , Polimetil Metacrilato/química , Cementos para Huesos/uso terapéutico , Diseño de Equipo , Humanos , Metilmetacrilato/uso terapéutico , Polimetil Metacrilato/uso terapéutico , Vacio
18.
Int J Cardiol ; 79(2-3): 237-43, 2001 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-11461747

RESUMEN

A new technology has been developed which measures the magnetic field of the human heart (magnetocardiogram, MCG) by using high temperature superconducting (HTS) sensors. These sensors can be operated at the temperature of liquid nitrogen without electromagnetic shielding. We tested the reproducibility of HTS-MCG measurements in healthy volunteers. Unshielded HTS-MCG measurements were performed in 18 healthy volunteers in left precordial position in two separate sessions in a clinical environment. The heart cycles of 10 min were averaged, smoothed, the baselines were adjusted, and the data were standardized to the respective areas under the curves (AUC) of the absolute values of the QRST amplitudes. The QRS complexes and the ST-T intervals were used to assess the reproducibility of the two measurements. Ratios (R(QRS), R(STT)) were calculated by dividing the AUC of the first measurement by the ones of the second measurement. The linear correlation coefficients (CORR(QRS), CORR(STT)) of the time intervals of the two measurements were calculated, too. The HTS-MCG signal was completely concealed by the high noise level in the raw data. The averaging and smoothing algorithms unmasked the QRS complex and the ST segment. A high reproducibility was found for the QRS complex (R(QRS)=1.2+/-0.3, CORR(QRS)=0.96+/-0.06). Similarly to the shape of the ECG it was characterized by three bends, the Q, R, and S waves. In the ST-T interval, the reproducibility was considerably lower (R(STT)=0.9+/-0.2, CORR(STT)=0.66+/-0.28). In contrast to the shape of the ECG, a baseline deflection after the T wave which may belong to U wave activity was found in a number of volunteers. HTS-MCG devices can be operated in a clinical environment without shielding. Whereas the reproducibility was found to be high for the depolarization interval, it was considerably lower for the ST segment and for the T wave. Therefore, before clinically applying HTS-MCG systems to the detection of repolarization abnormalities in acute coronary syndromes, further technical development of the systems is necessary to improve the signal-to-noise ratio.


Asunto(s)
Técnicas de Diagnóstico Cardiovascular/instrumentación , Sistema de Conducción Cardíaco/fisiología , Magnetismo/instrumentación , Adulto , Humanos , Modelos Lineales , Reproducibilidad de los Resultados , Estadísticas no Paramétricas
19.
Arch Phys Med Rehabil ; 77(11): 1157-60, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8931528

RESUMEN

OBJECTIVE: To identify the precise locations of the motor branches and motor points to the hamstring musculature and define these locations in relation to bony landmarks. DESIGN: Descriptive study of adult cadaver limb dissection. The number, location, and course of the motor branches and motor points to each hamstring muscle from the sciatic nerve were defined relative to bony landmarks. SETTING: Department of anatomy at a university school of medicine. PARTICIPANTS: Anatomic dissection of 30 adult cadaver limbs (17 individuals) was completed. Adult cadavers were selected randomly without regard to gender, age, and race. Exclusion criteria included femoral fracture, surgery, inability to obtain neutral position, and posterior thigh trauma. MAIN OUTCOME MEASURE: A descriptive anatomic study based on linear measures in centimeters from bony landmarks. RESULTS: Two zones located along a line from the ischial tuberosity to the lateral femoral condyle were observed to exist. Zone one, containing the first motor branch to the biceps long head and semitendinosus, is found at approximately 20% (6.9cm +/- 1.8 and 7.1cm +/- 2.2 from the ischial tuberosity, respectively) of femur length along the stated line. Zone two, containing the primary branch to the semimembranosus and the secondary branches to the biceps and semitendinosus, is found at approximately 33% (13.1cm +/- 3.6, 12.6cm +/- 3.9, and 14.3cm +/- 3.9 from the ischial tuberosity, respectively) of femur length. CONCLUSIONS: The drawing of one surface line, when combined with our anthropometric observations, should increase the ease and accuracy with which motor branch blocks to the hamstrings are performed.


Asunto(s)
Músculos/inervación , Nervios Periféricos/anatomía & histología , Adulto , Cadáver , Femenino , Humanos , Masculino , Neuronas Motoras , Nervio Ciático/anatomía & histología , Muslo
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