Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 65
Filter
1.
J Med Case Rep ; 11(1): 95, 2017 Apr 07.
Article in English | MEDLINE | ID: mdl-28385164

ABSTRACT

BACKGROUND: Micronodular lesions are common findings in lung imaging. As an important differential diagnosis, we describe a case of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia; it is notable that the diagnosis of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia is often delayed. This case provides supporting evidence to establish lung biopsy by cryotechnique as the option of first choice when considering a diagnostic strategy for micronodular lung lesions. CASE PRESENTATION: We report a case of a 65-year-old white woman who presented with obstructive symptoms of chronic coughing and dyspnea confirmed by conventional lung function tests. A computed tomography scan presented disseminated micronodules in all the lobes of her lungs. With the help of bronchoscopic cryobiopsy it was possible to obtain a high yield sample of lung parenchyma. On histologic examination, the micronodules correlated with a diffuse neuroendocrine cell hyperplasia. In the context of clinical symptoms, radiological aspects, and histomorphological aspects we made the diagnosis of a diffuse idiopathic pulmonary neuroendocrine cell hyperplasia. Obstructive symptoms were treated with inhaled steroids and beta-2-mimetics continuously. A comparison between current computed tomography scans of our patient and scans of 2014 revealed no significant changes. Last ambulatory checks occurred in January and May of 2016. The course of disease and the extent of limitation of lung function have remained stable. CONCLUSIONS: The diagnosis of diffuse idiopathic pulmonary neuroendocrine cell hyperplasia is best made in a multidisciplinary review including clinical presentation, lung imaging, and histomorphological aspects. This report and current literature indicate that transbronchial lung cryobiopsy can be used as a safe and practicable tool to obtain high quality biopsies of lung parenchyma in order to diagnose micronodular lesions of the lung.


Subject(s)
Cryosurgery , Hyperplasia/diagnosis , Lung Diseases, Interstitial/diagnosis , Lung/pathology , Neuroendocrine Cells/pathology , Thoracic Surgery, Video-Assisted , Tomography, X-Ray Computed , Aged , Albuterol/therapeutic use , Anti-Inflammatory Agents/therapeutic use , Biopsy/instrumentation , Bronchodilator Agents/therapeutic use , Budesonide/therapeutic use , Cough/etiology , Cryosurgery/methods , Dyspnea/etiology , Female , Formoterol Fumarate/therapeutic use , Humans , Hyperplasia/drug therapy , Hyperplasia/pathology , Lung Diseases, Interstitial/drug therapy , Lung Diseases, Interstitial/pathology , Prognosis , Respiratory Function Tests , Tiotropium Bromide/therapeutic use , Treatment Outcome
3.
Pneumologie ; 67(2): 112-7, 2013 Feb.
Article in German | MEDLINE | ID: mdl-23247596

ABSTRACT

Portable monitoring of sleep disordered breathing is the first diagnostic method not only in Germany but today in other countries as well. The conditions under which portable monitoring can be done with reliable results are now well defined. The limitations for the use of portable monitoring are specified as well. The devices used for portable monitoring are classified in four categories according to the number and the kind of signals recorded. New technical developments in the field of portable monitoring (polygraphy) use an indirect assessment of sleep disordered breathing based on signals not directly recording respiration. The recording of ECG and deriving respiration, the analysis of the plethysmographically recorded pulse wave, the recording of jaw movements using magnets, and advanced analysis of respiratory sounds are recent approaches. These new methods are presented with few studies until now. More and larger clinical studies are needed in order to show which of these systems is useful in the diagnosis of sleep disordered breathing and which are the specific strengths and weaknesses.


Subject(s)
Auscultation/methods , Electrocardiography/methods , Electroencephalography/methods , Photoplethysmography/methods , Polysomnography/methods , Sleep Apnea Syndromes/diagnosis , Spirometry/methods , Auscultation/instrumentation , Electrocardiography/instrumentation , Humans , Miniaturization , Polysomnography/instrumentation , Respiratory Sounds
4.
Nervenarzt ; 83(8): 1021-7, 2012 Aug.
Article in German | MEDLINE | ID: mdl-22878709

ABSTRACT

BACKGROUND: The most common diagnoses in sleep medicine are insomnia, sleep disordered breathing (SDB) and periodic leg movements (PLM). These disorders may coincide. This study examined the role of portable sleep monitoring in the diagnostic process and which sleep medicine diagnoses are additionally found in patients with disorders of initiating and maintaining sleep. METHODS: A total of 217 patients, including 103 men (47.5%) and 114 (52.5%) women aged 52.2 ± 13.6 years with disorders of initiating or maintaining sleep were included in the study. Patients with known SDB were excluded. Patients were investigated using a stepwise diagnostic procedure with clinical interviews, questionnaires, clinical examination and portable sleep recording with electromyography (EMG) of the tibialis anterior muscle to diagnose SDB and PLM. RESULTS: Of the patients 125 (57.6%) were diagnosed with insomnia according to the International Classification of Sleep Disorders (ICSD) and 70 (56%) had no other sleep disorder. Out of the 217 patients SDB was found in 107 (49.3%) patients, PLM in 90 patients (41.5%) and in 78 patients (35.9%) restless legs syndrome (RLS) was diagnosed. Among the 125 patients with insomnia 44 patients had RLS/PLMD and 35 had SDB in addition whereas SDB and RLS/PLMD were found in 33 subjects. All 3 disorders insomnia, RLS/PLMD and SDB were found in 24 subjects. CONCLUSIONS: Out of 217 patients with a complaint of non-restorative sleep only 125 were finally diagnosed with insomnia. As 25.3% of patients showed combinations of sleep disorders, 49.3% with SDB and 41.5% with RLS/PLMD portable monitoring with electromyography of the legs is recommended. The investigation with a portable sleep monitoring system including an EMG of the tibialis muscle is very useful in patients with insomnia in addition to a clinical interview and questionnaires.


Subject(s)
Polysomnography/instrumentation , Polysomnography/methods , Sleep Wake Disorders/diagnosis , Adult , Aged , Female , Humans , Male , Middle Aged , Miniaturization , Reproducibility of Results , Sensitivity and Specificity , Young Adult
5.
J Med Primatol ; 39(2): 92-6, 2010 Apr.
Article in English | MEDLINE | ID: mdl-19793177

ABSTRACT

BACKGROUND: Gallbladder pathology (GBP) is a relatively uncommon, naturally occurring morbidity in both baboons and humans. METHODS: A retrospective analysis was performed on 7776 necropsy reports over a 20 year period to determine the prevalence of baboon GBP. RESULTS: Ninety-seven cases of GBP were identified, yielding a 20 year population prevalence of 1.25%. GBP is more common in adult female baboons, occurring with a female to male ratio of nearly 2:1. Among gallbladder pathologies, cholecystitis (35.1%) and cholelithiasis (29.9%) were the most prevalent abnormalities, followed by hyperplasia (16.5%), edema (15.5%), amyloidosis (5.2%), fibrosis (4.1%), necrosis (4.1%), and hemorrhage (1.0%). CONCLUSION: Many epidemiologic similarities exist between GBP in baboons and humans suggesting that the baboon may serve as a reliable animal model system for investigating GBP in humans.


Subject(s)
Gallbladder Diseases/veterinary , Monkey Diseases/pathology , Papio , Age Factors , Animals , Female , Gallbladder Diseases/epidemiology , Gallbladder Diseases/pathology , Gallstones/chemistry , Histocytochemistry/veterinary , Male , Monkey Diseases/epidemiology , Prevalence , Retrospective Studies , Texas/epidemiology
6.
Clin Genet ; 73(2): 146-51, 2008 Feb.
Article in English | MEDLINE | ID: mdl-18177471

ABSTRACT

Glomerulonephritis, particularly IgA nephropathy (IgAN), seems to be more common in familial Mediterranean fever (FMF), an inherited disease caused by mutations in the MEditerranean FeVer gene (MEFV). The present study is aimed to determine, in populations not suffering from FMF, whether carriage of MEFV mutations may modify or precipitate IgAN and other forms of primary glomerulonephritis (PGN). Forty patients with biopsy proven IgAN and 40 with PGN were surveyed for the presence of the three most common MEFV mutations (M694V, V726A and E148Q), using polymerase chain reaction amplification and restriction enzyme analysis. The rate of MEFV mutations in the patients was related to the expected carrier rate in the general population of the same ethnic extraction. The effect of mutation carriage on the disease course was determined in the IgAN patient group. The frequency of MEFV mutations in IgAN or PGN was comparable to that found in ethnically adjusted general population (p = 0.1 and 0.5, respectively). Carriage of mutated MEFV was not associated with the course and severity of the disease or findings in kidney biopsy and urine analysis. In a population, mostly of Jewish extraction, MEFV mutations do not seem to predispose to the development of IgAN and other forms of PGN or affect the phenotype.


Subject(s)
Cytoskeletal Proteins/genetics , Familial Mediterranean Fever/genetics , Glomerulonephritis, IGA/genetics , Adult , DNA Mutational Analysis , Female , Humans , Male , Middle Aged , Pyrin
7.
Article in English | MEDLINE | ID: mdl-18003402

ABSTRACT

A monolithic microsystem in CMOS (complementary metal oxide semiconductor) technology is presented that provides bidirectional communication (stimulation and recording) between standard microelectronics and cultured electrogenic cells. The 128-electrode chip can be directly used as a substrate for cell culturing. It features circuitry units for stimulation and immediate cell signal treatment near each electrode. In addition, it provides on-chip A/D conversion as well as a digital interface so that a fast interaction is possible at good signal quality. Spontaneous and stimulated electrical activity recordings with neuronal and cardiac cell cultures will be presented. The system can be used to, e.g., study the behavior and development of neural networks in vitro, to reveal the effects of neuronal plasticity and to study network activity in response to pharmacological treatments.


Subject(s)
Action Potentials/physiology , Cell Culture Techniques/instrumentation , Electric Stimulation/instrumentation , Electronics/instrumentation , Microelectrodes , Neurons/physiology , Signal Processing, Computer-Assisted/instrumentation , Amplifiers, Electronic , Analog-Digital Conversion , Animals , Biotechnology/instrumentation , Cell Communication/physiology , Cell Culture Techniques/methods , Cells, Cultured , Electric Stimulation/methods , Equipment Design , Equipment Failure Analysis , Miniaturization , Myocytes, Cardiac/physiology , Rats
8.
Article in English | MEDLINE | ID: mdl-18001915

ABSTRACT

Recordings have been performed with a CMOS-based microelectrode array (MEA) featuring 11'016 metal electrodes and 126 channels, each of which comprises recording and stimulation electronics for extracellular, bidirectional communication with electrogenic cells. The important features of the device include (i) high spatial resolution at (sub) cellular level with 3'200 electrodes per mm(2) (diameter 7 microm, pitch 18 microm), (ii) a reconfigurable routing of the electrodes to the 126 channels, and (iii) low noise levels. Recordings from neonatal rat cardiomyocytes forming confluent layers and microtissues are shown. Moreover, signals from dissociated rat hippocampal neurons and from neurons in an acute cerebellar slice preparation are presented.


Subject(s)
Lab-On-A-Chip Devices , Myocytes, Cardiac/physiology , Neurons/physiology , Animals , Chickens , Electrodes , Image Processing, Computer-Assisted/instrumentation , Image Processing, Computer-Assisted/methods , Microchip Analytical Procedures/methods , Microelectrodes , Rats , Rats, Long-Evans
9.
J Neurosci Methods ; 164(1): 93-106, 2007 Aug 15.
Article in English | MEDLINE | ID: mdl-17540452

ABSTRACT

We report on the system integration of a CMOS chip that is capable of bidirectionally communicating (stimulation and recording) with electrogenic cells such as neurons or cardiomyocytes and that is targeted at investigating electrical signal propagation within cellular networks in vitro. The overall system consists of three major subunits: first, the core component is a 6.5 mm x 6.5 mm CMOS chip, on top of which the cells are cultured. It features 128 bidirectional electrodes, each equipped with dedicated analog filters and amplification stages and a stimulation buffer. The electrodes are sampled at 20 kHz with 8-bit resolution. The measured input-referred circuitry noise is 5.9 microV root mean square (10 Hz to 100 kHz), which allows to reliably detect the cell signals ranging from 1 mVpp down to 40 microVpp. Additionally, temperature sensors, a digital-to-analog converter for stimulation, and a digital interface for data transmission are integrated. Second, there is a reconfigurable logic device, which provides chip control, event detection, data buffering and an USB interface, capable of processing the 2.56 million samples per second. The third element includes software that is running on a standard PC performing data capturing, processing, and visualization. Experiments involving the stimulation of neurons with two different spatio-temporal patterns and the recording of the triggered spiking activity have been carried out. The response patterns have been successfully classified (83% correct) with respect to the different stimulation patterns. The advantages over current microelectrode arrays, as has been demonstrated in the experiments, include the capability to stimulate (voltage stimulation, 8 bit, 60 kHz) spatio-temporal patterns on arbitrary sets of electrodes and the fast stimulation reset mechanism that allows to record neuronal signals on a stimulating electrode 5 ms after stimulation (instantaneously on all other electrodes). Other advantages of the overall system include the small number of needed electrical connections due to the digital interface and the short latency time that allows to initiate a stimulation less than 2 ms after the detection of an action potential in closed-loop configurations.


Subject(s)
Electronics, Medical/instrumentation , Electrophysiology/instrumentation , Nerve Net/physiology , Neurons/physiology , Neurophysiology/instrumentation , Action Potentials/physiology , Animals , Animals, Newborn , Cell Culture Techniques/methods , Cells, Cultured , Electronics, Medical/methods , Electrophysiology/methods , Microelectrodes/standards , Microelectrodes/trends , Nerve Net/cytology , Neurons/cytology , Neurophysiology/methods , Rats , Rats, Sprague-Dawley , Reaction Time/physiology , Signal Processing, Computer-Assisted/instrumentation , Software
10.
Pneumologie ; 61(7): 458-66, 2007 Jul.
Article in German | MEDLINE | ID: mdl-17538860

ABSTRACT

Many patients with the obstructive sleep apnea syndrome (OSAS) look for alternative conservative or surgical therapies to avoid to be treated with continuous positive airway pressure. In view of the high prevalence and the relevant impairment of the patients lots of methods are offered which promise definitive cure or relevant improvement of OSAS. The working group "Apnea" in the German Society of Sleep Medicine and Research established a task force to evaluate the scientific literature on non-CPAP therapies in the treatment of OSAS according to the standards of evidence-based medicine. This paper summarizes the results of the task force. The data were unsatisfactorily for most of the methods. Sufficient data were available for intraoral appliances (IOA) and the maxillomandibular osteotomy (MMO). IOA's can reduce mild to moderate respiratory disturbances, MMO are efficient in the short and long term but are performed only in special situations such as craniofacial dysmorphias. Weight reduction and body positioning cannot be recommended as a single treatment of OSAS. Most surgical procedures still lack sufficient data according to the criteria of evidence based medicine. Resections of muscular tissue within the soft palate have to be strictly avoided. But even success following gentle soft palate procedures is difficult to predict and often decreases after years. Results in other anatomical regions seem to be more stable over time. Today combined surgeries in the sense of multi-level surgery concepts are of increasing interest in the secondary treatment after failure of nasal ventilation therapy although more data from prospective controlled studies are needed. There is no evidence for any other treatment options.


Subject(s)
Continuous Positive Airway Pressure , Sleep Apnea, Obstructive/therapy , Germany , Humans , Nasopharyngeal Diseases/therapy , Reproducibility of Results , Sleep Apnea, Obstructive/drug therapy , Sleep Apnea, Obstructive/epidemiology , Sleep Apnea, Obstructive/surgery , Societies, Medical , Tonsillectomy
11.
Eur Respir J ; 29(6): 1201-5, 2007 Jun.
Article in English | MEDLINE | ID: mdl-17360729

ABSTRACT

Studies from the USA have reported that sleep apnoea is common in congestive heart failure (CHF), with Cheyne-Stokes respiration (CSR) being the most frequent type of sleep-disordered breathing (SDB) in these patients. Within the present study, the authors sought to assess the prevalence and type of SDB among CHF patients in Germany. A total of 203 CHF patients participated in this prospective multicentre study. All patients were stable in New York Heart Association classes II and III and had a left ventricular ejection fraction (LVEF)<40%. The patients were investigated by polygraphy and all data were centrally analysed. Patient enrolment was irrespective of sleep-related symptoms. The majority of patients were male with a mean age of 65 yrs and hospitalised. Of the 203 patients, 145 (71%) had an apnoea/hypopnoea index>10.h(-1), obstructive sleep apnoea (OSA) occurred in 43% (n=88) and CSR in 28% (n=57) of patients. The prevalence of sleep-disordered breathing is high in patients with stable severe congestive heart failure from a European population. As sleep-disordered breathing may have a negative impact on the prognosis of congestive heart failure, a sleep study should be performed in every patient with congestive heart failure and a left ventricular ejection fraction of <40%. This diagnostic approach should probably be adopted for all of these patients irrespective of the presence of sleep-related symptoms.


Subject(s)
Heart Failure/complications , Heart Failure/diagnosis , Heart Failure/pathology , Sleep Apnea Syndromes/complications , Aged , Cheyne-Stokes Respiration , Continuous Positive Airway Pressure , Female , Humans , Male , Middle Aged , Oxygen Inhalation Therapy , Polysomnography/methods , Pressure , Respiration , Sleep , Sleep Apnea, Obstructive/diagnosis
12.
Biosens Bioelectron ; 22(11): 2546-53, 2007 May 15.
Article in English | MEDLINE | ID: mdl-17097869

ABSTRACT

A high degree of connectivity and the coordinated electrical activity of neural cells or networks are believed to be the reason that the brain is capable of highly sophisticated information processing. Likewise, the effectiveness of an animal heart largely depends on such coordinated cell activity. To advance our understanding of these complex biological systems, high spatiotemporal-resolution techniques to monitor the cell electrical activity and an ideally seamless interaction between cells and recording devices are desired. Here we present a monolithic microsystem in complementary metal oxide semiconductor (CMOS) technology that provides bidirectional communication (stimulation and recording) between standard electronics technology and cultured electrogenic cells. The microchip can be directly used as a substrate for cell culturing, it features circuitry units per electrode for stimulation and immediate cell signal treatment, and it provides on-chip signal transformation as well as a digital interface so that a very fast, almost real-time interaction (2 ms loop time from event recognition to, e.g., a defined stimulation) is possible at remarkable signal quality. The corresponding spontaneous and stimulated electrical activity recordings with neuronal and cardiac cell cultures will be presented. The system can be used to, e.g., study the development of neural networks, reveal the effects of neuronal plasticity and study cellular or network activity in response to pharmacological treatments.


Subject(s)
Action Potentials/physiology , Amplifiers, Electronic , Electric Stimulation/instrumentation , Microelectrodes , Myocytes, Cardiac/physiology , Neurons/physiology , Patch-Clamp Techniques/instrumentation , Animals , Cells, Cultured , Chickens , Electric Stimulation/methods , Equipment Design , Equipment Failure Analysis , Miniaturization , Rats , Transistors, Electronic
13.
Clin Nephrol ; 62(3): 226-8, 2004 Sep.
Article in English | MEDLINE | ID: mdl-15481855

ABSTRACT

IgA nephropathy is the most common primary glomerulopathy. Currently, no satisfactory treatment is available and as a result, a significant proportion of affected patients progress to end-stage renal disease. We present a patient with IgA nephropathy in whom continuous colchicine treatment induced remission, which has lasted for 22 years. The patient was a carrier of a mutation in the FMF gene (MEFV). This case raises hopes for a better prognosis in at least one subgroup of IgA nephropathy, consisting of patients who happen to be heterozygous carriers of MEFV mutations.


Subject(s)
Colchicine/therapeutic use , Familial Mediterranean Fever/genetics , Glomerulonephritis, IGA/drug therapy , Glomerulonephritis, IGA/genetics , Heterozygote , Adult , Humans , Male , Mutation
14.
Biosens Bioelectron ; 20(2): 358-66, 2004 Sep 15.
Article in English | MEDLINE | ID: mdl-15308242

ABSTRACT

Signal degradation and an array size dictated by the number of available interconnects are the two main limitations inherent to standalone microelectrode arrays (MEAs). A new biochip consisting of an array of microelectrodes with fully-integrated analog and digital circuitry realized in an industrial CMOS process addresses these issues. The device is capable of on-chip signal filtering for improved signal-to-noise ratio (SNR), on-chip analog and digital conversion, and multiplexing, thereby facilitating simultaneous stimulation and recording of electrogenic cell activity. The designed electrode pitch of 250 microm significantly limits the space available for circuitry: a repeated unit of circuitry associated with each electrode comprises a stimulation buffer and a bandpass filter for readout. The bandpass filter has corner frequencies of 100 Hz and 50 kHz, and a gain of 1000. Stimulation voltages are generated from an 8-bit digital signal and converted to an analog signal at a frequency of 120 kHz. Functionality of the read-out circuitry is demonstrated by the measurement of cardiomyocyte activity. The microelectrode is realized in a shifted design for flexibility and biocompatibility. Several microelectrode materials (platinum, platinum black and titanium nitride) have been electrically characterized. An equivalent circuit model, where each parameter represents a macroscopic physical quantity contributing to the interface impedance, has been successfully fitted to experimental results.


Subject(s)
Action Potentials/physiology , Amplifiers, Electronic , Cell Culture Techniques/instrumentation , Electric Stimulation/instrumentation , Electrophysiology/instrumentation , Microelectrodes , Myocytes, Cardiac/physiology , Animals , Cell Culture Techniques/methods , Chick Embryo , Chickens , Electric Stimulation/methods , Electrophysiology/methods , Equipment Design , Equipment Failure Analysis , Miniaturization , Transistors, Electronic
15.
J Biochem Biophys Methods ; 50(1): 15-27, 2001 Dec 04.
Article in English | MEDLINE | ID: mdl-11714508

ABSTRACT

In the context of a neurobionic approach to chemical analysis and sensorics, this article depicts the development of a miniaturized autonomous perfusion chamber setup for the growth and the electrical as well as optical investigation of (neural) cell cultures in vitro. We suggest an autonomous, modular, temperature-controlled, transparent, and sealed perfusion cell culture housing adaptable to various mounts, sizes and different needs. The design includes the electronics of a temperature and medium supply control unit. The setup combines the possibility of uninterrupted cell culturing with simultaneous microscopic and analytical investigation of variable amounts of cells or organs of human, animal, or plant origin under sterile conditions on different substrates without the need of an external incubator or a sterile working environment. Its use is demonstrated exemplarily with neuronal cultures from embryonic chicken that were cultured in a prototype system for 3 weeks. It turned out that cell survival in such a chamber was prolonged with timed medium flow rather than continuous perfusion.


Subject(s)
Cell Culture Techniques/instrumentation , Cell Culture Techniques/methods , Cytological Techniques/instrumentation , Animals , Biocompatible Materials , Brain/cytology , Chick Embryo , Hydrogen-Ion Concentration , Perfusion , Temperature
16.
J Neurosci Methods ; 112(1): 65-73, 2001 Nov 15.
Article in English | MEDLINE | ID: mdl-11640959

ABSTRACT

New strategies for spatially controllable cell adhesion have been developed for brain cells from embryonic chicken. They are based on electrochemically active phenol and pyrrole derivatives, and can be used for the selective coverage of electroconductive substrates. Besides mimicking standard laminin-related adhesion promoting mechanisms by means of an electroactive monomer-linked 18-peptide segment from laminin (SRARKQAASIKVAVSADR), electrochemically generated thin (6-30 nm) polymer films of 3-hydroxybenzyl-hydrazine (3HBH) and 2-(3-hydroxyphenyl)-ethanol (2(3HP)E) with and without mechanically entrapped or covalently linked D-lysine have proved to promote cell adhesion in serum-free medium on indium-doped tin oxide (ITO) substrates during the first 6 culturing days in vitro. The effectiveness of the peptide was strongly density-dependent. Unexpectedly, laminin itself or a combination of laminin and poly-D-lysine (PDL) did not promote cell adhesion and neuron differentiation in serum-free cultures on ITO. However, they worked perfectly well on regular polystyrene substrates in serum-free medium or on ITO when medium with serum was used. This finding might suggest that the adhesion efficiency of laminin does not depend only on the kind of medium supplement but also on the type of substrate. In contrast, the adhesion-promoting properties of "artificial" polymeric films seemed to be based on a more direct cell-film interaction, with the film masking the substrate properties.


Subject(s)
Cell Adhesion/drug effects , Central Nervous System/drug effects , Electrochemistry/methods , Laminin/metabolism , Membranes, Artificial , Neurons/drug effects , Peptide Fragments/metabolism , Polymers/metabolism , Animals , Cell Adhesion/physiology , Cell Culture Techniques/methods , Cell Division/drug effects , Cell Division/physiology , Cells, Cultured/cytology , Cells, Cultured/drug effects , Cells, Cultured/metabolism , Central Nervous System/cytology , Central Nervous System/metabolism , Chick Embryo , Culture Media/pharmacology , Epitopes/metabolism , Microscopy, Atomic Force , Neurons/cytology , Neurons/metabolism
17.
Neurorehabil Neural Repair ; 15(3): 239-44, 2001.
Article in English | MEDLINE | ID: mdl-11944746

ABSTRACT

OBJECTIVE: To examine the relationship of the Berg Balance Scale (BBS) to outcome after acquired brain injury. METHODS: Forty consecutive patients with acquired brain injury were admitted for multidisciplinary rehabilitation. Patients were assessed with the BBS. The BBS was originally designed as a quantitative measure of balance and risk for falls in community-dwelling elderly patients. The BBS comprises 14 different tasks graded on a 56-point scale. Community-dwelling elders with a BBS score of < or = 42 have > 90% risk for falls. RESULTS: In our study, there were 27 patients with a low BBS score (< or = 42) and 13 patients with a high BBS score (> or = 43). The discharge total Functional Independence Measure (FIM) scores were lower in the low BBS patients (96.4 +/- 21.2) compared with the high BBS patients (111.5 +/- 12.5) (p < 0.007). The length of stay (LOS) was significantly longer in the low BBS patients (38.9 +/- 18.5 days) compared with the high BBS patients (14.2 +/- 6.1 days; p < 0.000). Among the three patients that experienced falls during their hospitalization, all exhibited low BBS scores. The admission BBS score strongly correlated with admission total FIM scores (r = 0.86; p < 0.000) and moderately correlated with discharge total FIM scores (r = 0.56; p < 0.000) and LOS (r = -0.55; p < 0.000). Using a multiple regression analysis, the admission FIM score was found to be the better predictor of discharge FIM scores, and time admitted after injury was the better predictor of LOS. CONCLUSIONS: Prediction of rehabilitative outcome might be enhanced by the use of the BBS scores in combination with other clinical measures on admission to inpatient acute rehabilitation.


Subject(s)
Activities of Daily Living , Brain Injuries/physiopathology , Brain Injuries/rehabilitation , Accidental Falls/statistics & numerical data , Adolescent , Adult , Aged , Aged, 80 and over , Brain Injuries/epidemiology , Diagnostic Techniques, Neurological , Disability Evaluation , Female , Humans , Male , Middle Aged , Postural Balance , Predictive Value of Tests , Risk Factors , Severity of Illness Index
19.
Neurology ; 48(1): 95-101, 1997 Jan.
Article in English | MEDLINE | ID: mdl-9008501

ABSTRACT

Prediction of the functional outcome for patients with stroke has depended on the severity of impairment, location of brain injury, age, and general medical condition. This study compared admission and discharge functional outcome (Functional Independence Measure, FIM) and deficit severity (Fugl-Meyer, F-M) scores in a retrospective study of patients with similar neurologic impairments: homonymous hemianopia, hemisensory loss, and hemiparesis. CT-verified stroke location was the independent variable: cortical (n = 11), basal ganglia and internal capsule (normal cortex and thalamus, n = 13), or combined (cortical, basal ganglia, and internal capsule, n = 22). By 3 months on average after stroke, all groups demonstrated significantly improved motor function as measured by F-M scores. Patients with cortical lesions had the least CT-imaged damage and the best outcome. Patients with combined lesions and more extensive brain injury had significantly higher FIM scores (P < 0.05) than patients with injury restricted to the basal ganglia/ internal capsule. Patients with basal ganglia/internal capsule injury were more likely to have hypotonia, flaccid paralysis, and persistently impaired balance and ambulation performance. While all patients had a comparable rehabilitation experience, these results suggest that patients with stroke confined to the basal ganglia and internal capsule benefited less from therapy. Isolated basal ganglia stroke may cause persistent corticothalamic-basal ganglia interactions that are dysfunctional and impede recovery.


Subject(s)
Basal Ganglia Diseases/rehabilitation , Cerebrovascular Disorders/rehabilitation , Aged , Basal Ganglia Diseases/diagnostic imaging , Basal Ganglia Diseases/physiopathology , Cerebrovascular Disorders/diagnostic imaging , Cerebrovascular Disorders/physiopathology , Female , Hemianopsia/etiology , Hemianopsia/physiopathology , Hemiplegia/etiology , Hemiplegia/physiopathology , Humans , Male , Middle Aged , Motor Activity , Retrospective Studies , Sensation Disorders/etiology , Sensation Disorders/physiopathology , Tomography, X-Ray Computed
20.
Biosens Bioelectron ; 12(9-10): 883-92, 1997.
Article in English | MEDLINE | ID: mdl-9451781

ABSTRACT

Revealing the complex signal-processing mechanisms and interconnection patterns of the nervous system has long been an intriguing puzzle. As a contribution to its understanding the optimization of the impedance behavior of implantable electrode arrays with via holes is discussed here. Peripheral axons will regenerate through these holes allowing for simultaneous nerve stimulation and signal recording. This approach is part of the ESPRIT project INTER and may eventually lead to devices driving sensory motor prosthesis with closed loop control. In the first set of experiments, micromachined platinum electrode arrays were prepared, characterized and optimized for nerve signal recording. The results of these studies are based on impedance spectroscopy and microscopic techniques. Equivalent circuits were modeled describing formally the electrical response behavior with ohmic resistances between 500 omega and 10 k omega. To attain low impedances for all electrodes on the INTER device, platinum from H2PtCl6 was electrodeposited, and sputter technology as well as electrochemical deposition from H2IrCl6 solution were used to produce thin iridium films. For the former, a lift-off process was established at one of the institutes to generate electrode structures with a line width of 5 microns. As a result in all three cases the electrodes showed almost constant impedances over the entire frequency range (10 Hz-1 kHz), which is relevant for nerve signal recording. In the second set of experiments, electrodes were optimized to allow for nerve stimulation. For this purpose, the charge delivery capacity (CDC) had to be increased and the impedance had to be decreased. Iridium oxide is the material of choice, because its CDC is much higher than the CDC of platinum at 75 microC/cm2 (Ziaie et al., 1991, IEEE Sensors & Actuators Transducers, 6, 124-127). A significant increase of the electrochemically active surface of the electrode structures could be observed by measuring the surface roughness. In first experiments, an activated iridium oxide film was formed with cyclic voltammetry and was evaluated using scanning force microscopy and impedance spectroscopy. The evaluation of the cyclic voltammograms showed a CDC up to 400 mC/cm2 for sputter deposited and oxidatively treated iridium films. Further investigations are directed towards increasing the stability of the iridium oxide electrodes with regard to long-term implants. Parallel experiments aim at the controlled axon adhesion without changing the impedance behavior of the described electrodes.


Subject(s)
Microelectrodes , Nervous System Physiological Phenomena , Signal Transduction/physiology , Electric Impedance , Electric Stimulation , Electrochemistry , Iridium
SELECTION OF CITATIONS
SEARCH DETAIL
...