Search PubMed⌕ Search

Biomedical subjects

J Müller

Publications and source records attributed to J Müller.

At least 109 records · Page 6Linked to original sources

Progression of dysarthria and dysphagia in postmortem-confirmed parkinsonian disorders.

BACKGROUND: Dysarthria and dysphagia are known to occur in parkinsonian syndromes such as Parkinson disease (PD), dementia with Lewy bodies (DLB), corticobasal degeneration (CBD), multiple system atrophy (MSA), and progressive supranuclear palsy (PSP). Differences in the evolution of these symptoms have not been studied systematically in postmortem-confirmed cases. OBJECTIVE: To study differences in the evolution of dysarthria and dysphagia in postmortem-confirmed parkinsonian disorders. PATIENTS AND METHODS: Eighty-three pathologically confirmed cases (PD, n = 17; MSA, n = 15; DLB, n = 14; PSP, n = 24; and CBD, n = 13) formed the basis for a multicenter clinicopathological study organized by the National Institute of Neurological Disorders and Stroke, Bethesda, Md. Cases with enough clinicopathological documentation for the purpose of the study were selected from research and neuropathological files of 7 medical centers in 4 countries (Austria, France, England, and the United States). RESULTS: Median dysarthria latencies were short in PSP and MSA (24 months each), intermediate in CBD and DLB (40 and 42 months), and long in PD (84 months). Median dysphagia latencies were intermediate in PSP (42 months), DLB (43 months), CBD (64 months), and MSA (67 months), and long in PD (130 months). Dysarthria or dysphagia within 1 year of disease onset was a distinguishing feature for atypical parkinsonian disorders (APDs) (specificity, 100%) but failed to further distinguish among the APDs. Survival time after onset of a complaint of dysphagia was similar in PD, MSA, and PSP (15 to 24 months, P =.7) and latency to a complaint of dysphagia was highly correlated with total survival time (rho = 0.88; P<.001) in all disorders. CONCLUSIONS: Latency to onset of dysarthria and dysphagia clearly differentiated PD from the APDs, but did not help distinguish different APDs. Survival after onset of dysphagia was similarly poor among all parkinsonian disorders. Evaluation and adequate treatment of patients with PD who complain of dysphagia might prevent or delay complications such as aspiration pneumonia, which in turn may improve quality of life and increase survival time.

Aged↗

The auditory startle reaction in parkinsonian disorders.

The auditory startle reaction to an unexpected loud stimulus is regarded as a brainstem reflex originating in the nucleus reticularis pontis caudalis and being distributed up the brainstem and down the spinal cord along slowly conducting pathways. Auditory startle responses (ASR) have been reported absent or reduced in progressive supranuclear palsy (PSP), and delayed in Parkinson's disease (PD), but normal in multiple-system atrophy (MSA). For the first time we studied ASR in patients fulfilling the clinical criteria of dementia with Lewy bodies (DLB) (n = 8), a neurodegenerative disorder characterized by cortical and subcortical depositions of Lewy bodies resulting in parkinsonism and progressive cognitive decline. For comparison, we also investigated patients with PD (n = 10), MSA (n = 7), PSP (n = 10), and age-matched healthy controls (n = 10). ASR were elicited by binaural high-intensity auditory stimuli. Surface electromyographic activity was simultaneously recorded from facial, upper, and lower extremity muscles. For each muscle, we assessed response probability and measured latency, amplitude, duration, and habituation rate. Patients with DLB had fewer and abnormally delayed ASR of low amplitude and short duration in extremity muscles compared to healthy controls. Furthermore, we confirm and extend previous findings of abnormal ASR in PSP and PD, and also demonstrate exaggerated ASR in extremity muscles of MSA patients. The different patterns of ASR abnormalities may reflect distinct types of brainstem dysfunction in DLB.

Acoustic Stimulation↗

Dynamic balance function in phasic cervical dystonia following Botulinum toxin therapy.

Previous research by our group revealed normal dynamic balance function in pure tonic cervical dystonia (CD) with impaired equilibrium in phasic CD patients investigated at least 3 months following Botulinum toxin (BtxA) treatment. The current study was performed to determine whether impaired dynamic equilibrium in phasic CD is influenced by symptomatic treatment with BtxA. Dynamic balance was tested in 20 patients with phasic CD on a dynamic platform with a cylindrical curved base (stabilometer) 4 weeks following BtxA treatment. Balance was assessed by the linear displacement of the platform and the maximum amplitude of platform displacement with open and closed eyes and compared with pre-BtxA data. Despite a clinically significant BtxA-induced reduction of phasic head movements, none of the platform measures improved significantly. In addition, there was no correlation between the BtxA-induced clinical improvement and changes in any of the dynamic balance measures pre- vs. post-BtxA. In conclusion, the persistent dynamic balance impairment after effective BtxA therapy may indicate that disequilibrium in phasic CD does not simply reflect disturbed vestibular input from repetitive head oscillations, but argues in favour of different sensorimotor processing in tonic and phasic CD.

Adult↗

Bone mass after treatment of malignant lymphoma in childhood.

BACKGROUND: Sex hormone deficiency, growth hormone deficiency, skeletal irradiation, and treatment with corticosteroids or methotrexate may all cause reduction in bone mass after treatment for childhood malignant lymphoma. Previous studies of the bone mass of childhood cancer survivors often lacked adequate local reference data, and survivors of malignant lymphoma were never analyzed separately. PROCEDURE: The bone mass of survivors of childhood Hodgkin disease (n = 23) or non-Hodgkin lymphoma (n = 21) was measured by dual-energy X-ray absorptiometry a median of 11 years after diagnosis (range 2-25). Results were compared with local data on 463 healthy controls. RESULTS: Adjusted for gender and age, the mean whole-body bone mineral content and bone mineral areal density were slightly, but significantly, reduced (0.5 and 0.4 SD lower than predicted). The reduced bone mineral content was associated with a significantly reduced height, whereas the size-adjusted bone mass (bone mineral content for bone area) did not differ significantly from that of controls. Lower height was related to male gender and to cranial, thoracic, and lumbar spine irradiation. Whole-body bone mineral content and bone mineral density were lower in persons treated with lumbar spine irradiation and whole-body bone mineral content was higher in nine women receiving sex hormone replacement therapy or oral contraceptives. Whole-body bone mass was not related to the cumulated doses of corticosteroids or methotrexate. CONCLUSIONS: Eleven years after diagnosis of childhood Hodgkin disease or non-Hodgkin lymphoma, the whole-body bone mass of survivors was only slightly reduced and the size-adjusted bone mass was normal.

Absorptiometry, Photon↗

Efficacy and safety of a standardised 500 unit dose of Dysport (clostridium botulinum toxin type A haemaglutinin complex) in a heterogeneous cervical dystonia population: results of a prospective, multicentre, randomised, double-blind, placebo-controlled, parallel group study.

Results from a dose-ranging study in a selected group of de novo patients with rotational cervical dystonia (CD) suggest that 500 units of Dysport (Clostridium botulinum toxin type A haemaglutinin complex) is the optimal starting dose. The present study aimed to confirm the efficacy and safety profile of this dose in a population of CD patients more representative of those seen in a typical dystonia clinic. A total of 68 patients with moderate to severe CD (Tsui score > or = 9) were randomly assigned to receive placebo or Dysport 500 units. Treatment was administered according to the clinical pattern of head deviation, using a standardised injection protocol. A total of 21 patients (11 Dysport, 10 placebo) had not previously received botulinum toxin type A (BtxA) injections, and 47 patients (24 Dysport, 23 placebo) had received BtxA more than 12 weeks previously. Assessments were performed at baseline and weeks 4, 8 and 16. Patients defined as non-responders at week 4 were re-treated in an open phase with 500 units of Dysport at week 6, and were followed up at week 10. Significant between-group differences in Tsui scores were present at weeks 4 (p=0.001) and 8 (p=0.002). Similarly, there were significant between-group differences (p < 0.001) in patient and investigator assessments of response in favour of Dysport at weeks 4 and 8. Also, more Dysport (49%) than placebo (33%) patients were pain-free at week 4 (p=0.02). Overall, 30/35 (86 %) Dysport patients and 14/33 (42%) placebo patients were classified as responders at week 4. Adverse events were reported by 15/35 Dysport patients and 9/33 placebo patients. Open phase treatment produced improvements in Tsui (p < 0.001) and pain scores (p=0.011), and 23/24 patients were classified as responders. Although individual dose titration and muscle selection is desirable, this study demonstrated that a dose of 500 units of Dysport injected into clinically identified neck muscles without electromyographic guidance is safe and effective in the treatment of patients with the major clinical types of cervical dystonia.

Adolescent↗

Clinical characteristics of the geste antagoniste in cervical dystonia.

The geste antagoniste (moving an arm to the face or head) is a well-known clinical feature in cervical dystonia (CD) to alleviate the abnormal posture. The clinical phenomenology of these manoeuvres has not so far been assessed systematically. Fifty patients with idiopathic CD aware of at least one geste antagoniste (60% women, mean age at onset 44.1 years, mean disease duration 7.5 years) were subjected to a standardized investigation including a semiquantitative clinical rating scale and polymyographic recordings of six cervical muscles. Twenty-seven patients (54%) demonstrated more than one geste antagoniste (range 2-5). A clinically significant (> or = 30%) reduction of head deviation was observed in 41 patients (82 %). Dystonic head posture improved by a mean of 60 % along all planes by the geste manoeuvre with a complete cessation of head oscillations in nine of 33 patients (27 %) with phasic CD. No significant laterality of the "geste-arm" or the facial target area was found. The duration of geste-effects depended significantly on disease duration and determined the patient's self-rating of the benefit of the manoeuvre. EMG-polygraphy revealed two types of geste-induced polymyographic changes: a decrease in recruitment density and amplitude in at least one dystonic muscle (66%), and an increased tonic muscle activation in the remaining patients. The remarkable efficacy of the geste antagoniste and the considerable variety in performance, duration, and EMG-pattern of these manoeuvres warrant further investigation of the therapeutic use of sensorimotor stimulation, in particular for those CD patients who experience limited or no effect from botulinum toxin therapy.

Adolescent↗

Decreased oxidative stress in patients with idiopathic dilated cardiomyopathy one year after immunoglobulin adsorption.

OBJECTIVES: In a substudy to a recently reported investigation that demonstrated the benefit of immunoglobulin adsorption (immunoadsorption) for patients with idiopathic dilated cardiomyopathy (IDC), we tested whether this benefit is associated with a reduction of oxidative stress. BACKGROUND: The progression of cardiomyopathy is believed to be related to the increase of oxidative stress. Therefore, reduction of oxidative stress could be one of the effects of immunoadsorption for improvement of cardiac performance and clinical status. METHODS: Plasma markers for oxidative stress-thiobarbituric acid-reactive substances (TBARS), lipid peroxides (LPO), anti-oxidized low-density lipoprotein-autoantibodies (anti-oxLDL-AB), thiol groups and vitamin E-were compared in 31 patients, of whom 16 underwent immunoadsorption and 15 received conventional treatment (controls). All patients received a daily supplement of vitamins, minerals and trace elements. RESULTS: After one year, TBARS (p = 0.026), LPO (p = 0.026) and anti-oxLD

Adsorption↗

Decreased plasma concentration of brain natriuretic peptide as a potential indicator of cardiac recovery in patients supported by mechanical circulatory assist systems.

OBJECTIVES: We sought to investigate the relationship between the plasma concentration of brain natriuretic peptide (BNP), echocardiographic findings and the clinical outcome of patients supported with ventricular assist devices (VADs) to determine the role of BNP as a predictor for cardiac recovery. BACKGROUND: Ventricular unloading in patients with end-stage heart failure supported by VADs may lead to myocardial recovery. The BNP is produced in the myocardium in response to chronic volume overload, but the effects on it of ventricular unloading by VADs are largely unknown. METHODS: Twenty-one patients diagnosed with nonischemic cardiomyopathy and supported by VADs were evaluated for echocardiographic data and blood chemistry including BNP. They were divided into patients who died while on mechanical support (group I; n = 9), patients who were transplanted (group II; n = 8) and patients who were successfully weaned off the system and did not require transplantation (group III; n = 4). RESULTS: Brain natriuretic peptide plasma concentrations decreased significantly after initiation of mechanical circulatory support (p = 0.017). Furthermore, the changes in BNP plasma concentrations showed a faster decrease to normal levels within the first week after implantation of the VAD in patients who were weaned off the system (group III) compared to patients in group I and group II. CONCLUSIONS: This study shows that ventricular unloading with VADs decreases BNP plasma concentrations in patients who suffer from end-stage heart failure. Furthermore, we hypothesize that an early decrease of BNP plasma concentration may be indicative of recovery of ventricular function during mechanical circulatory support.

Adolescent↗

[The Plexitom, a new quality assurance tool for the linear accelerator].

Continuous depth dose measurements are generally performed in water phantoms. It is now possible to make continuous depth dose measurements in the solid PMMA phantom Plexitom, developed by our group and manufactured by PTW. The mechanical construction of this phantom allows the continuous movement of the ionisation chamber within the solid phantom. The Plexitom is light and very handy. It is very useful for quality assurance, especially to check the radiation quality of the linac.

Equipment Design↗

C-TAK1 regulates Ras signaling by phosphorylating the MAPK scaffold, KSR1.

Kinase suppressor of Ras (KSR) is a conserved component of the Ras pathway that interacts directly with MEK and MAPK. Here we show that KSR1 translocates from the cytoplasm to the cell surface in response to growth factor treatment and that this process is regulated by Cdc25C-associated kinase 1 (C-TAK1). C-TAK1 constitutively associates with mammalian KSR1 and phosphorylates serine 392 to confer 14-3-3 binding and cytoplasmic sequestration of KSR1 in unstimulated cells. In response to signal activation, the phosphorylation state of S392 is reduced, allowing the KSR1 complex to colocalize with activated Ras and Raf-1 at the plasma membrane, thereby facilitating the phosphorylation reactions required for the activation of MEK and MAPK.

Animals↗

Inducible nitric oxide synthase in the myocard.

Recognition of significance of nitric oxide synthases (NOS) in cardiovascular regulations has led to intensive research and development of therapies focused on NOS as potential therapeutic targets. However, the NOS isoform profile of cardiac tissue and subcellular localization of NOS isoforms remain a matter of debate. The aim of this study was to investigate the localization of an inducible NOS isoform (NOS2) in cardiomyocytes. Employing a novel immunocytochemical technique of a catalyzed reporter deposition system with tyramide and electron microscopical immunocytochemistry complemented with Western blotting and RT-PCR, we detected NOS2 both in rat neonatal and adult cultured cardiomyocytes and in the normal myocard of adult rats as well as in the human myocard of patients with dilative cardiomyopathy. NOS2 was targeted predominantly to a particulate component of the cardiomyocyte--along contractile fibers, in the plasma membrane including T-tubules, as well as in the nuclear envelope, mitochondria and Golgi complex. Our results point to an involvement of NOS2 in maintaining cardiac homeostasis and contradict to the notion that NOS2 is expressed in cardiac tissue only in response to various physiological and pathogenic factors. NOS2 targeting to mitochondria and contractile fibers suggests a relationship of NO with contractile function and energy production in the cardiac muscle.

Animals↗

Capacity for hormone production of cultured trophoblast cells obtained from placentae at term and in early pregnancy.

PROBLEM: There is an increased doubt about the identity of isolated cytotrophoblast cells at term. Therefore, we compared pregnancy serum levels of three hormones [human placental lactogen (hPL), human chorionic gonadotropin (hCG), and leptin] with the capacity for hormone production of early placentae [EP; 8-13 weeks of gestation (WG)] and term placentae (TP; 38-42 WG). METHODS: Serum levels of these hormones were determined in 15 paired maternal (7-41 WG) and fetal (37-41 WG) samples. Cytotrophoblast cells were isolated from term (TP; 38-42 weeks) and early (EP; 8-13 weeks) placentae by enzymatic digestion and subsequent purification on a Percoll gradient. These cells were cultured for 6 days. The production of the hormones hPL, hCG, and leptin was determined as release during culture + cell content after culture - cell content before culture. RESULTS: Serum levels (mean +/- SD; n = 15) at 7-12 and 37-41 WG were 89,652 +/- 21,431 and 13,620 +/- 5854 mIU/ml for hCG, 400 +/- 182 and 7088 +/- 2030 ng/ml for hPL, and 12,675 +/- 4266 and 32,236 +/- 10,961 pg/ml for leptin, respectively. For cultured cells from EP and TP, hCG and hPL showed different patterns of release during the first 2-3 days. While the release of these two hormones by EP cytotrophoblast cells continued during 6 days in culture, their concentrations reached a plateau for TP cytotrophoblasts between 4 and 6 days. Leptin was undetectable (< 15 pg/ml) in TP cell cultured media, while for EP all three hormones showed the same release profiles. Production calculated for 30,000 TP trophoblast cells cultured for 6 days (n = 8) was 2-31 mIU for hCG and 0.5-2 ng for hPL. For EP (n = 11), it was 50-1070 mIU for hCG, 15-323 ng for hPL, and 137-580 pg for leptin. Net synthesis of hCG and hPL for TP was > 10-fold and < 1-fold, respectively. In contrast, the production of all three hormones for EP was at least 100 times the initial cell content. CONCLUSIONS: These results demonstrate that trophoblasts from early pregnancy show much higher production rates of hCG, hPL, and leptin than at term. However, the in vitro findings are difficult to be reconciled with the different serum concentrations of the two hormones hPL and leptin observed during the course of pregnancy.

Cells, Cultured↗

Body proportions, body composition and pubertal development of children in competitive sports.

The aim of this study was primarily to investigate anthropometric variables, body composition and pubertal development in children aged 9-13 participating in competitive sports. Secondly, the influence of age, sport, training hours and pubertal development/maternal menarcheal age on body composition and pubertal development was explored. A total of 183 (96 girls, 87 boys) children performing swimming (Sw), tennis (Te), European team handball (TH), and gymnastics (Gy) took part in the study. Anthropometric measurements and pubertal development were determined. The participants completed a questionnaire regarding hours of training per week and maternal menarcheal age. Significant differences in stature (z-scores) were found in both boys (Sw=0.06; Te=0.04; TH=0.05; Gy=-0.66, P<0.004) and girls (Sw=0.12; Te=0.19; TH=0.25; Gy=-0.96, P<0.004). In girls, sum of skinfolds in millimetres (Sw=33.4; Te=33.3; TH=41.0; Gy= 27.2, P<0.02) and body mass index z-scores (SW=0.00; Te=-0.27; TH=0.35; Gy=-0.25, P<0.001) were different between the sports. A regression analysis revealed that in girls, age and maternal menarcheal age were significantly associated with pubertal development (P<0.005 and P<0.01), respectively, and sport was associated with the sum of skinfolds (P<0.05). In boys, only age was significantly associated with pubertal development (P<0.005). In conclusion, anthropometric and body composition differences exist in athletes of both sexes from different sports but are more evident in females. Most importantly, we did not find any effect of training on body composition or pubertal development, confirming previous data that children in competitive sports are selected due to constitutional factors.

Adolescent↗

Degree of fatness after allogeneic BMT for childhood leukaemia or lymphoma.

Excess fatness is frequent after childhood ALL treated without BMT. We measured the whole-body percent fat by dual-energy X-ray absorptiometry and the body-mass index (weight/height(2) (kg/m(2)), BMI) in 25 survivors of childhood leukaemia or lymphoma (21 with ALL) who had received TBI and allogeneic BMT a median of 8 years ago (range 4-13). Adjusted for sex and age, the mean BMI was slightly but significantly reduced (0.4 s.d. below predicted) and the whole-body percent fat was significantly increased compared with healthy controls (1.1 s.d. above predicted). Eleven of 25 patients had a percent fat above the 90 percentile of the reference values, which indicates excess fatness. Adjusted for sex and age, a higher percent fat was related to additional cranial irradiation. Controlled for this, the whole-body percent fat seemed to be unrelated to age at BMT, length of follow-up, and previous chemotherapy. Compared with untransplanted ALL survivors treated with cranial irradiation, BMT survivors had significantly reduced BMI but similar whole body percent fat. BMI was a poor measure of body fatness in these patients. In conclusion, survivors of BMT for childhood leukaemia or lymphoma are adipose and slightly underweight and consequently have a substantially reduced lean body mass.

Body Composition↗