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1.
Childs Nerv Syst ; 36(9): 1955-1965, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32588175

RESUMEN

INTRODUCTION: Spinal reflexes reorganize in cerebral palsy (CP), producing hyperreflexia and spasticity. CP is more common among male infants, and gender might also influence brain and spinal-cord reorganization. This retrospective study investigated the frequency of higher-graded EMG responses elicited by electrical nerve-root stimulation during selective dorsal rhizotomy (SDR), prior to partial nerve- root deafferentation, considering not only segmental level and body side, but also gender. METHODS: Intraoperative neuromonitoring (IOM) was used in SDR to pinpoint the rootlets most responsible for exacerbated stimulation-evoked EMG patterns recorded from lower-limb muscle groups. Responses were graded according to an objective response-classification system, ranging from no abnormalities (grade 0) to highly abnormal (grade 4+), based on ipsilateral spread and contralateral involvement. Non-parametric analysis of data with repeated measures was primarily used in investigating the frequency distribution of these various EMG response grades. Over 7000 rootlets were stimulated, and the results for 65 girls and 81 boys were evaluated, taking changes in the composition of patient groups into account when considering GMFCS levels. RESULTS: The distribution of graded EMG responses varied according to gender, laterality, and level. Higher-graded EMG responses were markedly more frequent in the boys and at lower segmental levels (L5, S1). Left-biased asymmetry in higher-graded rootlets was also more noticeable in the boys and in patients with GMFCS level I. A close link was observed between higher-grade assessments and left-biased asymmetry. CONCLUSIONS: Detailed insight into the patient's initial spinal-neurofunctional state prior to deafferentation suggests that differences in asymmetrical spinal reorganization might be attributable to a hemispheric imbalance.


Asunto(s)
Parálisis Cerebral , Rizotomía , Parálisis Cerebral/cirugía , Niño , Electromiografía , Femenino , Humanos , Lactante , Masculino , Espasticidad Muscular/cirugía , Estudios Retrospectivos , Caracteres Sexuales , Raíces Nerviosas Espinales/cirugía
2.
Ann Neurol ; 79(2): 206-16, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26537743

RESUMEN

OBJECTIVE: Neuromyelitis optica (NMO) attacks often are severe, are difficult to treat, and leave residual deficits. Here, we analyzed the frequency, sequence, and efficacy of therapies used for NMO attacks. METHODS: A retrospective review was made of patient records to assess demographic/diagnostic data, attack characteristics, therapies, and the short-term remission status (complete remission [CR], partial remission [PR], no remission [NR]). Inclusion criteria were NMO according to Wingerchuk's 2006 criteria or aquaporin-4 antibody-positive NMO spectrum disorder (NMOSD). Remission status was analyzed with generalized estimating equations (GEEs), a patient-based statistical approach. RESULTS: A total of 871 attacks in 185 patients (142 NMO/43 NMOSD, 82% female) were analyzed. The 1,153 treatment courses comprised high-dose intravenous steroids (HD-S; n = 810), plasma exchange (PE; n = 192), immunoadsorption (IA; n = 38), other (n = 80), and unknown (n = 33) therapies. The first treatment course led to CR in 19.1%, PR in 64.5%, and NR in 16.4% of attacks. Second, third, fourth, and fifth treatment courses were given in 28.2%, 7.1%, 1.4%, and 0.5% of attacks, respectively. This escalation of attack therapy significantly improved outcome (p < 0.001, Bowker test). Remission rates were higher for isolated optic neuritis versus isolated myelitis (p < 0.001), and for unilateral versus bilateral optic neuritis (p = 0.020). Isolated myelitis responded better to PE/IA than to HD-S as first treatment course (p = 0.037). Predictors of CR in multivariate GEE analysis were age (odds ratio [OR] = 0.97, p = 0.011), presence of myelitis (OR = 0.38, p = 0.002), CR from previous attack (OR = 6.85, p < 0.001), and first-line PE/IA versus HD-S (OR = 4.38, p = 0.006). INTERPRETATION: Particularly myelitis and bilateral optic neuritis have poor remission rates. Escalation of attack therapy improves outcome. PE/IA may increase recovery in isolated myelitis.


Asunto(s)
Neuromielitis Óptica/terapia , Evaluación de Resultado en la Atención de Salud/estadística & datos numéricos , Sistema de Registros/estadística & datos numéricos , Adulto , Femenino , Alemania , Humanos , Masculino , Persona de Mediana Edad , Neuromielitis Óptica/tratamiento farmacológico , Inducción de Remisión , Estudios Retrospectivos
3.
J Neural Transm (Vienna) ; 122(2): 253-6, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24872078

RESUMEN

LSVT-BIG is an exercise for patients with Parkinson's disease (PD) comprising of 16 1-h sessions within 4 weeks. LSVT-BIG was compared with a 2-week short protocol (AOT-SP) consisting of 10 sessions with identical exercises in 42 patients with PD. UPDRS-III-score was reduced by -6.6 in LSVT-BIG and -5.7 in AOT-SP at follow-up after 16 weeks (p < 0.001). Measures of motor performance were equally improved by LSVT-BIG and AOT-SP but high-intensity LSVT-BIG was more effective to obtain patient-perceived benefit.


Asunto(s)
Terapia por Ejercicio , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/rehabilitación , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Estadísticas no Paramétricas , Factores de Tiempo , Resultado del Tratamiento
4.
Arch Phys Med Rehabil ; 95(5): 996-9, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24231400

RESUMEN

OBJECTIVE: To determine whether physical activity may affect cognitive performance in patients with Parkinson's disease by measuring reaction times in patients participating in the Berlin BIG study. DESIGN: Randomized controlled trial, rater-blinded. SETTING: Ambulatory care. PARTICIPANTS: Patients with mild to moderate Parkinson's disease (N=60) were randomly allocated to 3 treatment arms. Outcome was measured at the termination of training and at follow-up 16 weeks after baseline in 58 patients (completers). INTERVENTIONS: Patients received 16 hours of individual Lee Silverman Voice Treatment-BIG training (BIG; duration of treatment, 4wk), 16 hours of group training with Nordic Walking (WALK; duration of treatment, 8wk), or nonsupervised domestic exercise (HOME; duration of instruction, 1hr). MAIN OUTCOME MEASURES: Cued reaction time (cRT) and noncued reaction time (nRT). RESULTS: Differences between treatment groups in improvement in reaction times from baseline to intermediate and baseline to follow-up assessments were observed for cRT but not for nRT. Pairwise t test comparisons revealed differences in change in cRT at both measurements between BIG and HOME groups (intermediate: -52ms; 95% confidence interval [CI], -84/-20; P=.002; follow-up: 55ms; CI, -105/-6; P=.030) and between WALK and HOME groups (intermediate: -61ms; CI, -120/-2; P=.042; follow-up: -78ms; CI, -136/-20; P=.010). There was no difference between BIG and WALK groups (intermediate: 9ms; CI, -49/67; P=.742; follow-up: 23ms; CI, -27/72; P=.361). CONCLUSION: Supervised physical exercise with Lee Silverman Voice Treatment-BIG or Nordic Walking is associated with improvement in cognitive aspects of movement preparation.


Asunto(s)
Terapia por Ejercicio/métodos , Enfermedad de Parkinson/rehabilitación , Calidad de Vida , Tiempo de Reacción/fisiología , Caminata/fisiología , Anciano , Berlin , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Enfermedad de Parkinson/fisiopatología , Estudios Retrospectivos , Resultado del Tratamiento
6.
Cerebrovasc Dis ; 25(1-2): 50-8, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18033958

RESUMEN

BACKGROUND: We have recently shown that ischemic stroke causes a stress-mediator-induced long-lasting immunodepressive state in mice. METHODS: Using head magnetic resonance imaging and standardized immunoassays, we prospectively investigated whether poststroke immunodepression is also seen in humans. RESULTS: Compared to healthy volunteers (n = 30), a rapid depression of lymphocyte counts and a functional deactivation of monocytes and T helper type 1 cells was observed in acute stroke patients (SP; n = 40). Immunodepression was more pronounced in patients with severe clinical deficit or large infarction. On admission the combination of monocytic tumor necrosis factor alpha release ex vivo and the National Institute of Health Stroke Scale score were the best predictors for nosocomial infection, preferentially affecting older SP. CONCLUSION: Our data provide evidence for an immediate suppression of cell-mediated immune responses after ischemic stroke in humans.


Asunto(s)
Isquemia Encefálica/inmunología , Infección Hospitalaria/epidemiología , Tolerancia Inmunológica/fisiología , Inmunidad Celular/fisiología , Accidente Cerebrovascular/inmunología , Anciano , Anciano de 80 o más Años , Isquemia Encefálica/complicaciones , Isquemia Encefálica/patología , Estudios de Casos y Controles , Estudios de Cohortes , Femenino , Humanos , Incidencia , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/patología
7.
Chronobiol Int ; 23(3): 593-605, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16753944

RESUMEN

The aim of this study was to explore differences between left-and right-handed subjects in sleep duration. Sleep and activity patterns were continuously registered for 12 days using actometers on 20 left-handed and 20 right-handed medical students in Berlin. Handedness was determined by a modified version of the Edinburgh handedness inventory. Each participant wore one actometer on each wrist. Actiwatch Sleep Analysis Software (CNT, UK) was used to evaluate the data, and statistical calculations were performed with a non-parametric variance analysis. A significant difference in mean sleep duration between left-handers (7.9 h) and right-handers (7.3 h) was determined (p=0.025 for measurement made on the dominant hand and p=0.013 for ones made on the non-dominant hand). In contrast, the maximal phase of daily activity (acrophase) did not show any difference between the two groups. The difference in sleep duration might be caused by either the greater effort required for left-handers to cope in a right-handed world or by structural brain differences.


Asunto(s)
Ritmo Circadiano/fisiología , Lateralidad Funcional/fisiología , Ciclos de Actividad/fisiología , Adulto , Femenino , Humanos , Masculino , Caracteres Sexuales , Sueño/fisiología
8.
Am J Kidney Dis ; 43(3): 444-53, 2004 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-14981602

RESUMEN

BACKGROUND: High-cutoff hemofilters are characterized by an increased effective pore size designed to facilitate the elimination of inflammatory mediators in sepsis. This study compares diffusive versus convective high-cutoff renal replacement therapy (RRT) in terms of cytokine clearance rates and effects on plasma protein levels. METHODS: Twenty-four patients with sepsis-induced acute renal failure were studied. A polyflux hemofilter with a cutoff point of approximately 60 kd was used for RRT. Patients were randomly allocated to either continuous venovenous hemofiltration (CVVH) with an ultrafiltration rate of 1 L/h (group 1) or 2.5 L/h (group 2) or continuous venovenous hemodialysis (CVVHD) with a dialysate flow rate of 1 L/h (group 3) or 2.5 L/h (group 4). Interleukin-1 (IL-1) receptor antagonist (IL-1ra), IL-1beta, IL-6, tumor necrosis factor-alpha (TNF-alpha), and plasma proteins were measured daily. RESULTS: CVVH achieved significantly greater IL-1ra clearance compared with CVVHD (P = 0.0003). No difference was found for IL-6 (P = 0.935). Increasing ultrafiltration volume or dialysate flow led to a highly significant increase in IL-1ra and IL-6 clearance rates (P < 0.00001). Peak clearances were 46 mL/min for IL-1ra and 51 mL/min for IL-6. TNF-alpha clearance was poor for both RRT modalities. A significant decline in plasma IL-1ra and IL-6 clearance was observed in patients with high baseline levels. Protein and albumin losses were greatest during the 2.5-L/h hemofiltration mode. CONCLUSION: High-cutoff RRT is a novel strategy to clear cytokines more effectively. Convection has an advantage over diffusion in the clearance capacity of IL-1ra, but is associated with greater plasma protein losses.


Asunto(s)
Hemofiltración , Fallo Renal Crónico/terapia , Diálisis Renal , Adulto , Anciano , Proteínas Sanguíneas , Citocinas/sangre , Femenino , Hemofiltración/instrumentación , Humanos , Fallo Renal Crónico/etiología , Fallo Renal Crónico/inmunología , Masculino , Persona de Mediana Edad , Choque Séptico/complicaciones
9.
J Clin Periodontol ; 34(6): 523-44, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17509093

RESUMEN

AIM: This systematic literature review was performed to investigate if smoking interferes with the prognosis of implants with and without accompanying augmentation procedures compared with non-smokers. METHODS: A systematic electronic and handsearch (articles published between 1989 and 2005; English and German language; search terms "dental or oral implants and smoking"; "dental or oral implants and tobacco") was performed to identify publications providing numbers of failed implants, related to the numbers of smokers and non-smokers for meta-analysis. Publications providing statistically examined data of implant failures or biologic complications among smokers compared with non-smokers were included for systematic review. RESULTS: Of 139 publications identified, 29 were considered for meta-analysis and 35 for systematic review. Meta-analysis revealed a significantly enhanced risk for implant failure among smokers [implant-related odds ratio (OR) 2.25, confidence interval (CI(95%)) 1.96-2.59; patient-related OR 2.64; CI(95%) 1.70-4.09] compared with non-smokers, and for smokers receiving implants with accompanying augmentation procedures (OR 3.61; CI(95%) 2.26-5.77, implant related). The systematic review indicated significantly enhanced risks of biologic complications among smokers. Five studies revealed no significant impact of smoking on prognosis of implants with particle-blasted, acid-etched or anodic oxidized surfaces. CONCLUSION: Smoking is a significant risk factor for dental implant therapy and augmentation procedures accompanying implantations.


Asunto(s)
Implantación Dental Endoósea , Implantes Dentales , Fumar , Aumento de la Cresta Alveolar , Diseño de Prótesis Dental , Fracaso de la Restauración Dental , Humanos , Pronóstico , Factores de Riesgo , Propiedades de Superficie
10.
J Heart Lung Transplant ; 25(1): 90-8, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16399536

RESUMEN

BACKGROUND: Previous studies have shown that passive epicardial constraint using a cardiac support device (CSD) reduces left ventricular (LV) size. However, specific data describing LV shape and the time course of changes in LV geometry are still incomplete. Thus, the aim of this study was-using 3-dimensional data sets obtained by computed tomography (CT)-to test the hypothesis that the CSD not only alters LV size but also LV shape, and that short-term post-operative changes in LV geometry are maintained during long-term follow-up. METHODS: Ten patients with non-ischemic dilated cardiomyopathy underwent electron-beam CT examination before and again at 2.6 +/- 0.5 and 32.4 +/- 8.7 months after CSD implantation. At end-diastole and end-systole LV volumes, the length-to-width diameter ratio and a sphericity index were determined and ejection fraction and end-systolic meridional and circumferential wall stress were calculated. RESULTS: Implantation of the CSD led to a significant reduction in LV size, a more ellipsoidal LV shape and a subsequent decrease of LV wall stress post-operatively (p < 0.05 for each), but no substantial changes were found between short- and long-term follow-up (p > 0.05 each). Mean pre-operative and early and late post-operative end-diastolic values were 310.4 +/- 87.8, 235.5 +/- 102.0 and 229.4 +/- 103.1 ml for volume; 1.27 +/- 0.20, 1.37 +/- 0.20 and 1.38 +/- 0.20 for diameter ratio; and 0.78 +/- 0.22, 0.67 +/- 0.26 and 0.65 +/- 0.23 for sphericity index. A similar pattern was observed for end-systolic values. Ejection fraction was 23.4 +/- 6.2%, 32.9 +/- 11.6% and 34.4 +/- 14.9%. End-systolic meridional and circumferential wall stress was 182.2 +/- 45.6, 128.2 +/- 52.6, 130.6 +/- 56.7 kdyn/cm(2) and 411.5 +/- 94.0, 297.4 +/- 108.4 and 302.8 +/- 117.5 kdyn/cm(2), respectively. CONCLUSIONS: Three-dimensional data obtained by CT demonstrate that passive cardiac constraint leads not only to a size reduction but also to an ellipsoidal re-shaping. Our data indicate that these effects are primarily a short-term consequence of the CSD implantation but are maintained during long-term follow-up.


Asunto(s)
Cardiomiopatía Dilatada/cirugía , Ventrículos Cardíacos/anatomía & histología , Ventrículos Cardíacos/diagnóstico por imagen , Corazón Auxiliar/efectos adversos , Remodelación Ventricular , Cardiomiopatía Dilatada/diagnóstico por imagen , Estudios de Casos y Controles , Diástole , Insuficiencia Cardíaca/cirugía , Humanos , Imagenología Tridimensional , Masculino , Persona de Mediana Edad , Insuficiencia de la Válvula Mitral , Estudios Prospectivos , Estudios Retrospectivos , Sístole , Tomografía Computarizada por Rayos X , Función Ventricular Izquierda
11.
Crit Care Med ; 34(8): 2099-104, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16763508

RESUMEN

OBJECTIVE: High cutoff hemofilters are characterized by an increased effective pore size designed to facilitate the elimination of inflammatory mediators in sepsis. Clinical data on this new renal replacement modality are lacking. DESIGN: Prospective, randomized clinical trial. SETTING: University hospital, intensive care units. PATIENTS: : Thirty patients with sepsis-induced acute renal failure. INTERVENTION: Patients were allocated to high cutoff (n = 20) or conventional (n = 10) hemofiltration in a 2:1 ratio. Median renal replacement dose was 31 mL/kg/hr. For high cutoff hemofiltration, a high-flux hemofilter with an in vivo cutoff point of approximately 60 kilodaltons was used. Conventional hemofiltration was performed with a standard high-flux hemofilter (PF11S). The impacts of high cutoff hemofiltration on the need for norepinephrine and on plasma levels and clearance rates for interleukin (IL)-6 and IL-1 receptor antagonist (IL-1ra) were analyzed. Absolute values, but also adjusted values (expressed as proportion of baseline), were analyzed. The observation period was restricted to 48 hrs. MAIN RESULTS: Apart from higher antithrombin III levels at entry into the study, main clinical and laboratory parameters were comparable between both groups. The median norepinephrine dose at entry into the study was 0.30 microg/kg/min in the high cutoff group and 0.21 microg/kg/min in the conventional hemofiltration group (p = .448). Only the high cutoff group showed a significant decline (p = .0002) in "adjusted" norepinephrine dose over time. Clearance rates for IL-6 and IL-1ra were significantly higher in the high cutoff hemofiltration group (p < .0001), which translated into a significant decline of the corresponding plasma levels (p = .0465 for IL-6; p = .0293 for IL-1ra). CONCLUSION: In this pilot study, high cutoff hemofiltration has been shown to exert a beneficial effect on the need for norepinephrine in septic patients with acute renal failure. In addition, we demonstrate that high cutoff hemofiltration is superior to conventional hemofiltration in the elimination of IL-6 and IL-1ra from the circulating blood of septic patients.


Asunto(s)
Lesión Renal Aguda/terapia , Hemofiltración/métodos , Norepinefrina/uso terapéutico , Sepsis/sangre , Vasoconstrictores/uso terapéutico , Lesión Renal Aguda/sangre , Lesión Renal Aguda/inmunología , Agonistas Adrenérgicos beta/uso terapéutico , Anciano , Proteína C-Reactiva/análisis , Dobutamina/uso terapéutico , Epinefrina/uso terapéutico , Femenino , Humanos , Unidades de Cuidados Intensivos , Interleucina-6/sangre , Masculino , Persona de Mediana Edad , Proyectos Piloto , Estudios Prospectivos , Receptores de Interleucina-1/antagonistas & inhibidores , Sepsis/inmunología
12.
Artif Organs ; 30(9): 686-94, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-16934097

RESUMEN

Primary human liver cells from donor organs unsuitable for transplantation were cultivated in bioreactors developed for extracorporeal liver support. Because each system contains cells originating from an individual organ, each bioreactor culture must be individually characterized. The objective of this study was to identify suitable decisive parameters for the evaluation of cell culture performance. We analyzed the data from 47 bioreactor cultures containing 437 +/- 110 g of cells. Choosing urea production as the decisive parameter, the bioreactor cultures were divided into high-performance (daily urea production > or = 110 mg per bioreactor between culture days 3 and 14) and low-performance cultures. Comparing the mean courses of the groups revealed a significant distinction in most other investigated biochemical parameters. In conclusion, urea production seems to be an appropriate parameter for evaluating the performance of liver cell cultures in bioreactors because it corresponds to all other evaluated parameters of cell function.


Asunto(s)
Reactores Biológicos , Hepatocitos/metabolismo , Preservación de Órganos/instrumentación , Urea/metabolismo , Adulto , Anciano , Albúminas/metabolismo , Técnicas de Cultivo de Célula , Diseño de Equipo , Femenino , Humanos , Ácido Láctico/metabolismo , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo
13.
Nephrol Dial Transplant ; 18(7): 1361-9, 2003 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-12808174

RESUMEN

BACKGROUND: Renal replacement therapies with high cut-off haemofilters are new approaches in the adjuvant therapy of sepsis. We analysed the cytokine elimination capacity of a newly developed polyflux high cut-off haemofilter. Different renal replacement therapies are compared and tested for their clinical feasibility. METHODS: Blood from healthy volunteers (n=15) was incubated for 4 h with 1 mg of endotoxin and then circulated through a closed extracorporeal circuit. A newly developed polyflux haemofilter (P2SX) was used. Haemofiltration, haemodialysis and albumin dialysis were tested. IL-1ra (17 kDa), interleukin-6 (IL-6) (28 kDa), tumour necrosis factor alpha (TNF-alpha) (51 kDa), albumin (64 kDa), creatinkinase (CK) (80 kDa) and IgG (140 kDa) were measured in blood and filtrates prior to the initiation and after 5 min, 1, 2 and 4 h. RESULTS: Haemofiltration was superior to haemodialysis in the clearance capacity of all substances when applied in the 1 l/h ultrafiltration mode. Increasing the ultrafiltration rate/dialysate flow from 1 to 3 l/h led to a significant increase in cytokine clearances (P<0.001). At 3 l/h the differences between haemofiltration and haemodialysis vanished and both techniques achieved comparable cytokine clearances. Median clearance values ranged between 25 and 54 ml/min for interleukin-1 receptor antagonist (IL-1ra), 23 and 42 ml/min for IL-6 and 15 and 28 ml/min for TNF-alpha. Albumin loss was highest in the haemofiltration group with albumin clearances ranging between 7 and 13 ml/min. Using diffusion instead of convection significantly reduced the loss of albumin (P<0.01 for 1 l/h, P<0.05 for 3 l/h). Albumin dialysis was able to completely inhibit albumin loss but cytokine clearance capacity was limited. CONCLUSIONS: High cut-off haemofilters achieve high clearances for inflammatory IL-6 and TNF-alpha. Due to the high protein loss in haemofiltration, dialysis in combination with balanced protein substitution seems to be a suitable approach for clinical trials.


Asunto(s)
Lesión Renal Aguda/terapia , Lesión Renal Aguda/orina , Antineoplásicos/orina , Citocinas/orina , Hemofiltración/instrumentación , Interleucina-6/orina , Diálisis Renal/instrumentación , Sepsis/terapia , Sepsis/orina , Factor de Necrosis Tumoral alfa/orina , Lesión Renal Aguda/etiología , Adulto , Diseño de Equipo , Estudios de Factibilidad , Humanos , Técnicas In Vitro , Valores de Referencia , Sepsis/complicaciones , Factores de Tiempo
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