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1.
Behav Brain Res ; 416: 113534, 2022 01 07.
Article in English | MEDLINE | ID: mdl-34416300

ABSTRACT

Species recognition is an essential behavioral outcome of social discrimination, flocking, mobbing, mating, and/or parental care. In songbirds, auditory species recognition cues are processed through specialized forebrain circuits dedicated to acoustic discrimination. Here we addressed the direction of behavioral and neural metrics of zebra finches' (Taeniopygia guttata) responses to acoustic cues of unfamiliar conspecifics vs. heterospecifics. Behaviorally, vocal response rates were greater for conspecific male zebra finch songs over heterospecific Pin-tailed Whydah (Vidua macroura) songs, which paralleled greater multiunit spike rates in the auditory forebrain in response to the same type of conspecific over heterospecific auditory stimuli. In contrast, forebrain activation levels were reversed to species-specific song playbacks during two functional magnetic resonance imaging experiments: we detected consistently greater responses to whydah songs over finch songs and did so independently of whether subjects had been co-housed or not with heterospecifics. These results imply that the directionality of behavioral and neural response selectivity metrics are not always consistent and appear to be experience-independent in this set of stimulus-and-subject experimental paradigms.


Subject(s)
Auditory Perception/physiology , Cues , Finches/physiology , Prosencephalon/physiology , Recognition, Psychology/physiology , Vocalization, Animal/physiology , Acoustic Stimulation , Animals , Electrophysiology , Magnetic Resonance Imaging , Male , Species Specificity
2.
J Intellect Disabil Res ; 63(10): 1262-1272, 2019 10.
Article in English | MEDLINE | ID: mdl-31237063

ABSTRACT

BACKGROUND: Advance care planning (ACP) is a process in which professionals, patients and their relatives discuss wishes and options for future care. ACP in the palliative phase reduces the chance that decisions have to be taken suddenly and can therefore improve the quality of life and death. The primary aim of this study is to explore how ACP takes place in cases of people with intellectual disabilities (ID). METHOD: Medical files were analysed, and interviews were held in six care organisations for people with mild to severe ID. The data concerned people with ID (n = 30), 15 in the palliative phase, identified using the 'surprise question', and 15 who had died after an identifiable period of illness. Additional pre-structured telephone interviews were conducted with their relatives (n = 30) and professionals (n = 33). RESULTS: For half of the people with ID who had died, the first report in their file about palliative care (needs) was less than 1 month before their death. Professionals stated that ACP was started in response to the person's deteriorating health situation. A do-not-attempt-resuscitation order was recorded for nearly all people with ID (93%). A smaller group also had other agreements between professionals and relatives documented in their files, mainly about potentially life-sustaining treatments (43%) and/or hospitalisation admissions (47%). Relatives and professionals are satisfied with the mutual cooperation in ACP in the palliative phase. Cognitive and communication disabilities were most frequently mentioned by relatives and professionals as reasons for not involving people with ID in ACP. CONCLUSIONS: Advance care planning in the palliative phase of people with ID focuses mainly on medical issues at the end of life. Specific challenges concern a proactive identification of changing needs, fear to initiate ACP discussions, documentation of ACP in medical files and the involvement of people with ID in ACP. It is recommended that relatives and professionals should be informed about the content of ACP and professionals should be trained in communicating in advance about wishes for future care.


Subject(s)
Advance Care Planning , Intellectual Disability/therapy , Palliative Care , Resuscitation Orders , Adult , Advance Care Planning/statistics & numerical data , Aged , Aged, 80 and over , Female , Humans , Male , Medical Records , Middle Aged , Netherlands , Palliative Care/statistics & numerical data , Qualitative Research
3.
Sci Adv ; 5(2): eaat7603, 2019 02.
Article in English | MEDLINE | ID: mdl-30775433

ABSTRACT

Adopting the framework of brain dynamics as a cornerstone of human consciousness, we determined whether dynamic signal coordination provides specific and generalizable patterns pertaining to conscious and unconscious states after brain damage. A dynamic pattern of coordinated and anticoordinated functional magnetic resonance imaging signals characterized healthy individuals and minimally conscious patients. The brains of unresponsive patients showed primarily a pattern of low interareal phase coherence mainly mediated by structural connectivity, and had smaller chances to transition between patterns. The complex pattern was further corroborated in patients with covert cognition, who could perform neuroimaging mental imagery tasks, validating this pattern's implication in consciousness. Anesthesia increased the probability of the less complex pattern to equal levels, validating its implication in unconsciousness. Our results establish that consciousness rests on the brain's ability to sustain rich brain dynamics and pave the way for determining specific and generalizable fingerprints of conscious and unconscious states.


Subject(s)
Brain/physiology , Connectome , Consciousness , Neural Pathways , Adult , Brain Mapping , Female , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Neuroimaging
4.
Article in Russian | MEDLINE | ID: mdl-30412153

ABSTRACT

The sensitivity of fMRI in identification of eloquent cortical centers in the case of large infiltrative growing tumors and pronounced peritumoral edema may be reduced or significantly limited in some cases. The main cause is an attenuated Blood-Oxygen-Level-Dependent response (BOLD) caused by pathological vascular reactivity and subsequent neurovascular uncoupling of fMRI. In our study, we attempted to overcome these limitations and increase the sensitivity of this technique in identification of eloquent cortical areas adjacent to brain tumors by using vasoreactivity features of a breath-holding test and including these data in the BOLD analysis. Local vasoreactivity using a breath-holding paradigm with the same block design of both motor and speech tests was determined in 5 healthy volunteers and 3 patients in the preoperative period (two patients with high grade gliomas and one patient with single metastasis). A coherence-based model was developed for analysis of BOLD fMRI, which took into account altered hemodynamics in peritumoral zones. Obtained coherence maps demonstrated clinically more significant activation zones that were not seen with standard methods of fMRI processing. Thus, neurovascular uncoupling that is known to affect the accuracy of the BOLD fMRI response adjacent to brain tumors may be partially overcome by including an independent measurement of vasoreactivity using a breath-holding test in the BOLD analysis.


Subject(s)
Brain Mapping , Brain Neoplasms , Magnetic Resonance Imaging , Brain , Brain Neoplasms/diagnostic imaging , Cerebrovascular Circulation , Humans , Oxygen
5.
J Neurosci Methods ; 309: 153-160, 2018 11 01.
Article in English | MEDLINE | ID: mdl-30194040

ABSTRACT

BACKGROUND: Weak or low intensity transcranial stimulation of the brain, such as low field magnetic stimulation and electrical stimulation, can produce significant functional and therapeutic neuromodulatory effects. NEW METHOD: We have recently developed a portable wearable multifocal brain stimulator called transcranial rotating permanent magnet stimulator (TRPMS) that uses rapidly spinning high field strength permanent magnets attached to a cap. It produces oscillatory stimuli of different frequencies and patterns. Here we compared the strengths and spatial profiles of the changing magnetic fields of a figure-of-eight transcranial magnetic stimulator (TMS) coil, a TRPMS prototype, and a scaled-up version of TRPMS. We measured field strengths and directions of voltages induced in a magnetic field sensor oriented along all three orthogonal axes. RESULTS AND COMPARISON WITH EXISTING METHODS: The spatial spread of the TRPMS-induced electric field is more restricted, and its shape and strength vary less with the orientation of the inductance than TMS. The maximum voltage induced by the current prototype is ∼7% of the maximal TMS output at depths corresponding to the human cerebral cortex from the scalp surface. This field strength can be scaled up by a factor ∼8 with a larger diametrically magnetized magnet. These comparative data allow us to estimate that intracortical effects of TRPMS could be stronger than other low intensity stimulation methods. CONCLUSIONS: TRPMS might enable greater uniformity, consistency and focality in stimulation of targeted cortical areas subject to significant anatomical variability. Multiple TRPMS microstimulators can also be combined to produce patterned multifocal spatiotemporal stimulation.


Subject(s)
Electromagnetic Fields , Transcranial Magnetic Stimulation/instrumentation , Transcranial Magnetic Stimulation/methods , Humans , Software , Wearable Electronic Devices
6.
Sci Rep ; 7: 39594, 2017 01 06.
Article in English | MEDLINE | ID: mdl-28059103

ABSTRACT

Viral vector mediated gene therapy has become commonplace in clinical trials for a wide range of inherited disorders. Successful gene transfer depends on a number of factors, of which tissue tropism is among the most important. To date, definitive mapping of the spatial and temporal distribution of viral vectors in vivo has generally required postmortem examination of tissue. Here we present two methods for radiolabeling adeno-associated virus (AAV), one of the most commonly used viral vectors for gene therapy trials, and demonstrate their potential usefulness in the development of surrogate markers for vector delivery during the first week after administration. Specifically, we labeled adeno-associated virus serotype 10 expressing the coding sequences for the CLN2 gene implicated in late infantile neuronal ceroid lipofuscinosis with iodine-124. Using direct (Iodogen) and indirect (modified Bolton-Hunter) methods, we observed the vector in the murine brain for up to one week using positron emission tomography. Capsid radioiodination of viral vectors enables non-invasive, whole body, in vivo evaluation of spatial and temporal vector distribution that should inform methods for efficacious gene therapy over a broad range of applications.


Subject(s)
Brain/diagnostic imaging , Capsid Proteins/analysis , Dependovirus/genetics , Gene Transfer Techniques , Genetic Vectors/analysis , Iodine Radioisotopes/administration & dosage , Radionuclide Imaging/methods , Aminopeptidases/metabolism , Capsid Proteins/radiation effects , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/metabolism , Genetic Therapy/methods , Humans , Male , Positron-Emission Tomography , Serine Proteases/metabolism , Tripeptidyl-Peptidase 1 , Urea/analogs & derivatives , Urea/pharmacology
7.
HNO ; 65(4): 328-336, 2017 Apr.
Article in German | MEDLINE | ID: mdl-27878599

ABSTRACT

BACKGROUND: According to international standards, determination of acoustic reflex thresholds (ART) is one of the established objective measurements in the diagnostic workup of central auditory processing disorders (CAPD). However, there is still no evidence for the significance of ART in CAPD diagnosis. PATIENTS AND METHODS: This study tested 57 children with proven CAPD and 50 healthy children (control group) with regard to group differences in mean ART (sine tones or bandpass-filtered noise). Additionally, it was investigated whether there were group differences between the mean dissociations of ART for sine tones or bandpass filtered noise. RESULTS: Neither ipsi- nor contralaterally were significant clinically relevant group differences (p < 0.050) between the mean ART of children with and without CAPD found. After Bonferroni correction, a significant group difference in the percentage of non-triggered reflexes was only observed with left-sided contralateral 2 kHz stimuli. Concerning the number of dissociations ≥20 dB, no significant group differences (p < 0.050) were detected either ipsi- or contralaterally (Fisher's test). CONCLUSION: The results of the study seem to indicate no clinically relevant ability of ART measurements to distinguish between children with and without CAPD. This renders the benefit of ART measurements for CAPD diagnosis questionable.


Subject(s)
Hearing Tests/methods , Language Development Disorders/diagnosis , Language Development Disorders/physiopathology , Reflex, Acoustic , Acoustic Stimulation , Child , Female , Humans , Language Development Disorders/classification , Male , Reproducibility of Results , Sensitivity and Specificity , Sensory Thresholds
8.
Neuroimage Clin ; 11: 635-647, 2016.
Article in English | MEDLINE | ID: mdl-27200264

ABSTRACT

Following severe injuries that result in disorders of consciousness, recovery can occur over many months or years post-injury. While post-injury synaptogenesis, axonal sprouting and functional reorganization are known to occur, the network-level processes underlying recovery are poorly understood. Here, we test a network-level functional rerouting hypothesis in recovery of patients with disorders of consciousness following severe brain injury. This hypothesis states that the brain recovers from injury by restoring normal functional connections via alternate structural pathways that circumvent impaired white matter connections. The so-called network diffusion model, which relates an individual's structural and functional connectomes by assuming that functional activation diffuses along structural pathways, is used here to capture this functional rerouting. We jointly examined functional and structural connectomes extracted from MRIs of 12 healthy and 16 brain-injured subjects. Connectome properties were quantified via graph theoretic measures and network diffusion model parameters. While a few graph metrics showed groupwise differences, they did not correlate with patients' level of consciousness as measured by the Coma Recovery Scale - Revised. There was, however, a strong and significant partial Pearson's correlation (accounting for age and years post-injury) between level of consciousness and network diffusion model propagation time (r = 0.76, p < 0.05, corrected), i.e. the time functional activation spends traversing the structural network. We concluded that functional rerouting via alternate (and less efficient) pathways leads to increases in network diffusion model propagation time. Simulations of injury and recovery in healthy connectomes confirmed these results. This work establishes the feasibility for using the network diffusion model to capture network-level mechanisms in recovery of consciousness after severe brain injury.


Subject(s)
Brain Injuries/pathology , Brain Injuries/physiopathology , Brain Mapping , Connectome , Models, Theoretical , Neural Pathways , Adult , Brain Injuries/diagnostic imaging , Female , Humans , Image Processing, Computer-Assisted , Magnetic Resonance Imaging , Male , Middle Aged , Neural Pathways/diagnostic imaging , Neural Pathways/physiopathology , Oxygen/blood , Young Adult
9.
AJNR Am J Neuroradiol ; 37(6): 1160-9, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26822727

ABSTRACT

BACKGROUND AND PURPOSE: Late infantile neuronal ceroid lipofuscinosis (CLN2 disease) is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene. Our hypothesis was that regional analysis of cortical brain degeneration may identify brain regions that are affected earliest and most severely by the disease. MATERIALS AND METHODS: Fifty-two high-resolution 3T MR imaging datasets were prospectively acquired on 38 subjects with CLN2. A retrospective cohort of 52 disease-free children served as a control population. The FreeSurfer software suite was used for calculation of cortical thickness. RESULTS: An increased rate of global cortical thinning in CLN2 versus control subjects was the primary finding in this study. Three distinct patterns were observed across brain regions. In the first, subjects with CLN2 exhibited differing rates of cortical thinning versus age. This was true in 22 and 26 of 34 regions in the left and right hemispheres, respectively, and was also clearly discernable when considering brain lobes as a whole and Brodmann regions. The second pattern exhibited a difference in thickness from healthy controls but with no discernable change with age (9 left hemispheres, 5 right hemispheres). In the third pattern, there was no difference in either the rate of cortical thinning or the mean cortical thickness between groups (3 left hemispheres, 3 right hemispheres). CONCLUSIONS: This study demonstrates that CLN2 causes differential rates of degeneration across the brain. Anatomic and functional regions that degenerate sooner and more severely than others compared with those in healthy controls may offer targets for directed therapies. The information gained may also provide neurobiologic insights regarding the mechanisms underlying disease progression.


Subject(s)
Brain/pathology , Nerve Degeneration/pathology , Neuronal Ceroid-Lipofuscinoses/pathology , Child , Disease Progression , Female , Humans , Magnetic Resonance Imaging , Male , Retrospective Studies , Tripeptidyl-Peptidase 1
10.
Hautarzt ; 66(3): 167-72, 2015 Mar.
Article in German | MEDLINE | ID: mdl-25604435

ABSTRACT

BACKGROUND: Health care of patients with occupational dermatitis (OD) in the sense of suspected "BK 5101" is carried out in Germany within the optimized dermatologist's procedure and the "dermal intervention" (formerly: hierarchical multistep intervention approach) of the statutory accident insurance (UVT), respectively. OBJECTIVES AND METHODS: Dermatologists and UVT administrators are obliged to improve OD patient care by continuous quality management measures. Essential quality management elements include the research projects EVA_Haut and VVH, the clearing procedure of the Task Force on Occupational and Environmental Dermatology (ABD), training of dermatologists to receive the CME certificate "Occupational Dermatology (ABD)", the establishment of processing standards for administrators and optimized dermatologist's report forms (based on the results of all the above steps taken). RESULTS: It was shown that the optimized dermatologist's procedure and "dermal intervention" are established in Germany. Also, the available preventive and therapeutic measures for OD patients are effective. Despite the increase of cases with suspected OD, the number of cases in which a career change was required is almost constant (3 %); at the same time the percentage of notified cases which, as a result, are covered within the dermatologist's procedure by the UVT is rising (86 %). The measures recently taken have continuously increased quality of health care in occupational dermatology.


Subject(s)
Certification/standards , Dermatitis, Occupational/diagnosis , Dermatitis, Occupational/prevention & control , Dermatology/standards , Occupational Medicine/standards , Quality Assurance, Health Care/standards , Germany , Humans , Practice Guidelines as Topic
11.
Nervenarzt ; 86(2): 210-8, 2015 Feb.
Article in German | MEDLINE | ID: mdl-25631121

ABSTRACT

At the University of Munich the teaching and treatment of neurological diseases had been covered by internists since the last quarter of the nineteenth century. Under the direction of Bumke the psychiatric clinic also laid claim to the representation of neurology starting in 1924. However, the military departments for nerve- and brain-injured soldiers, which were founded during WWI, developed into non-academic neurological treatment centres in Munich with donations from the German-American philanthropist Heckscher and the initiative of war invalids organisations. In 1925 the Heckscher Nerven-Heil- und Forschungsanstalt was established as the first neurological hospital in Munich. The main characters involved in this development were the neurologist Eugen von Malaisé and the psychiatrist Max Isserlin. With the early death of von Malaisé in 1923 neurology in Munich lost an important advocate of its institutional independence. The dismissal, prosecution and expulsion of the Jewish chief physician Isserlin was the second heavy blow to the efforts towards autonomy of neurology in Munich.


Subject(s)
Hospitals, Special/history , National Socialism/history , Neurology/history , Germany , History, 20th Century
12.
AJNR Am J Neuroradiol ; 34(4): 884-9, 2013 Apr.
Article in English | MEDLINE | ID: mdl-23042927

ABSTRACT

BACKGROUND AND PURPOSE: LINCL is a uniformly fatal lysosomal storage disease resulting from mutations in the CLN2 gene that encodes for tripeptidyl peptidase 1, a lysosomal enzyme necessary for the degradation of products of cellular metabolism. With the goal of developing quantitative noninvasive imaging biomarkers sensitive to disease progression, we evaluated a 5-component MR imaging metric and tested its correlation with a clinically derived disease-severity score. MATERIALS AND METHODS: MR imaging parameters were measured across the brain, including quantitative measures of the ADC, FA, nuclear spin-spin relaxation times (T2), volume percentage of CSF (%CSF), and NAA/Cr ratios. Thirty MR imaging datasets were prospectively acquired from 23 subjects with LINCL (2.5-8.4 years of age; 8 male/15 female). Whole-brain histograms were created, and the mode and mean values of the histograms were used to characterize disease severity. RESULTS: Correlation of single MR imaging parameters against the clinical disease-severity scale yielded linear regressions with R2 ranging from 0.25 to 0.70. Combinations of the 5 biomarkers were evaluated by using PCA. The best combination included ADC, %CSF, and NAA/Cr (R2=0.76, P<.001). CONCLUSIONS: The multiparametric disease-severity score obtained from the combination of ADC, %CSF, and NAA/Cr whole-brain MR imaging techniques provided a robust measure of disease severity, which may be useful in clinical therapeutic trials of LINCL in which an objective assessment of therapeutic response is desired.


Subject(s)
Brain/pathology , Magnetic Resonance Imaging/methods , Neuronal Ceroid-Lipofuscinoses/pathology , Severity of Illness Index , Age Factors , Aminopeptidases/genetics , Artifacts , Biomarkers/metabolism , Brain/metabolism , Child , Child, Preschool , Databases, Factual , Dipeptidyl-Peptidases and Tripeptidyl-Peptidases/genetics , Disease Progression , Female , Humans , Male , Neuronal Ceroid-Lipofuscinoses/genetics , Serine Proteases/genetics , Tripeptidyl-Peptidase 1
13.
Med Image Anal ; 16(6): 1142-55, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22677817

ABSTRACT

We introduce an algorithm for diffusion weighted magnetic resonance imaging data enhancement based on structural adaptive smoothing in both voxel space and diffusion-gradient space. The method, called POAS, does not refer to a specific model for the data, like the diffusion tensor or higher order models. It works by embedding the measurement space into a space with defined metric, in this case the Lie group of three-dimensional Euclidean motion SE(3). Subsequently, pairwise comparisons of the values of the diffusion weighted signal are used for adaptation. POAS preserves the edges of the observed fine and anisotropic structures. It is designed to reduce noise directly in the diffusion weighted images and consequently also to reduce bias and variability of quantities derived from the data for specific models. We evaluate the algorithm on simulated and experimental data and demonstrate that it can be used to reduce the number of applied diffusion gradients and hence acquisition time while achieving a similar quality of data, or to improve the quality of data acquired in a clinically feasible scan time setting.


Subject(s)
Algorithms , Brain/anatomy & histology , Diffusion Magnetic Resonance Imaging/methods , Image Enhancement/methods , Image Interpretation, Computer-Assisted/methods , Reproducibility of Results , Sensitivity and Specificity
14.
Phys Med Biol ; 57(4): 1113-34, 2012 Feb 21.
Article in English | MEDLINE | ID: mdl-22297259

ABSTRACT

Magnetic particle imaging (MPI) is a new tomographic imaging method which is able to capture the fast dynamic behavior of magnetic tracer material. From measured induced signals, the unknown magnetic particle concentration is reconstructed using a previously determined system function, which describes the relation between particle position and signal response. After discretization, the system function is represented by a matrix, whose size can prohibit the use of direct solvers for matrix inversion to reconstruct the image. In this paper, we present a new reconstruction approach, which combines efficient compression techniques and iterative reconstruction solvers. The data compression is based on orthogonal transforms, which extract the most relevant information from the system function matrix by thresholding, such that any iterative solver is strongly accelerated. The effect of the compression with respect to memory requirements, computational complexity and image quality is investigated. With the proposed method, it is possible to achieve real-time reconstruction with almost no loss in image quality using measured 4D MPI data.


Subject(s)
Image Processing, Computer-Assisted/methods , Magnets , Tomography/methods , Animals , Data Compression , Heart , Mice , Phantoms, Imaging , Time Factors
15.
Scand J Public Health ; 40(2): 126-32, 2012 Mar.
Article in English | MEDLINE | ID: mdl-22316573

ABSTRACT

AIM: This study investigated the proportion of Danish patients in cardiac therapy for ischaemic heart disease who participated in cardiac rehabilitation. The study examined differences in patients' participation in and experience and satisfaction with cardiac rehabilitation. METHODS: Data were obtained from a postal questionnaire in a representative sample of patients in therapy for an ischaemic heart disease. Response data were tabulated and analysed by logistic regression. RESULTS: 3% of the patients participated in a complete rehabilitation programme according to Danish standards, 47% of the patients participated in a partial rehabilitation programme, and additionally 32% of the patients participated in a very limited rehabilitation programme. The number of patients participating in a complete rehabilitation programme was low due to the fact that only few patients (and their relatives) received psychological support. The factors living alone and low education are associated with low participation and in particular with receiving psychological support. Elderly (≥50 years) and male patients showed higher satisfaction scores. Patients receiving psychosocial elements in their rehabilitation programme reported higher satisfaction with their rehabilitation. CONCLUSIONS: Few Danish patients with ischaemic heart disease participate in a complete rehabilitation programme mainly due to psychosocial elements not yet being an integral part of cardiac rehabilitation in Denmark. There is a need to differentiate and tailor cardiac rehabilitation to different patient segments, e.g. by gender and age.


Subject(s)
Ambulatory Care/statistics & numerical data , Ischemia/rehabilitation , Patient Participation , Patient Satisfaction , Adult , Age Factors , Aged , Denmark , Educational Status , Female , Humans , Logistic Models , Male , Middle Aged , Population Surveillance , Sex Factors , Social Support , Socioeconomic Factors , Surveys and Questionnaires
16.
J Neurosci Methods ; 203(1): 200-11, 2012 Jan 15.
Article in English | MEDLINE | ID: mdl-21925539

ABSTRACT

In this paper we develop a tensor mixture model for diffusion weighted imaging data using an automatic model order selection criterion for the number of tensor components in a voxel. We show that the weighted orientation distribution function for this model can be expanded into a mixture of angular central Gaussian distributions. We investigate properties of this model in extensive simulations and in a high angular resolution scan of a human brain. The results suggest that the model improves imaging of cerebral fiber tracts. In addition, inference on canonical model parameters could potentially provide novel clinical markers of altered white matter. Software to compute the tensor mixture model from diffusion weighted MRI data is made available in the programming language R.


Subject(s)
Brain/anatomy & histology , Computer Simulation , Image Interpretation, Computer-Assisted/methods , Models, Theoretical , Neural Pathways/anatomy & histology , Adult , Algorithms , Diffusion Tensor Imaging , Humans , Male , Models, Neurological , Normal Distribution , Software
17.
Neurology ; 77(16): 1518-23, 2011 Oct 18.
Article in English | MEDLINE | ID: mdl-21940616

ABSTRACT

OBJECTIVE: To use arterial spin labeling (ASL) to compare cerebral blood flow (CBF) patterns in minimally conscious state (MCS) patients with those in normal controls in an observational study design. METHODS: Subjects meeting MCS criteria and normal controls were identified. A pseudocontinuous ASL sequence was performed with subjects and controls in the resting awake state. Multiple CBF values for 10 predetermined regions of interest were sampled and average CBF was calculated and compared between controls and subjects. RESULTS: Ten normal controls were identified, with ages ranging from 26 to 54 years. Four subjects met the MCS criteria and received an ASL study, with one patient receiving a second study at a later date. Subjects ranged in age from 19 to 58 years and had traumatic brain injury, stroke, or hypoxic-ischemic encephalopathy. Regional CBF for controls ranged from 21.6 to 57.2 mL/100 g/min, with a pattern of relatively increased blood flow posteriorly including the posterior cingulate, parietal, and occipital cortices. CBF patterns for MCS subjects showed greater variability (from 7.7 to 33.1 mL/100 g/min), demonstrating globally decreased CBF in gray matter compared with that in normal controls, especially in the medial prefrontal and midfrontal regions. In the one subject studied longitudinally, global CBF values increased over time, which correlated with clinical improvement. CONCLUSIONS: We identified globally decreased CBF and a selective reduction of CBF within the medial prefrontal and midfrontal cortical regions as well as gray matter in MCS patients. ASL may serve as an adjunctive method to assess functional reserve in patients recovering from severe brain injuries.


Subject(s)
Arteries/physiopathology , Cerebral Cortex/blood supply , Cerebrovascular Circulation/physiology , Persistent Vegetative State/physiopathology , Spin Labels , Adult , Brain Mapping , Female , Humans , Image Processing, Computer-Assisted/methods , Magnetic Resonance Imaging , Male , Middle Aged , Observation , Oxygen/blood , Persistent Vegetative State/metabolism , Young Adult
18.
Hautarzt ; 60(9): 695-701, 2009 Sep.
Article in German | MEDLINE | ID: mdl-19629414

ABSTRACT

Parallel to the introduction of the optimized dermatologist's report in 2006, a hierarchical multi-step intervention approach to occupational dermatitis (OD) was launched within the statutory accident insurance bodies. It is aimed at ensuring that OD patients can be allocated to dermatological consultations and preventive measures quickly and in a manner appropriate to the severity of their OD. At present, a study ("EVA Haut") is being conducted at the University of Osnabrueck in which about 10% of the annually reported cases in Germany with suspected OD in 2007 have been selected at random (N=1,600). All randomized notifications are reviewed by occupational dermatologists; in parallel, the implementation of the hierarchical multi-step intervention scheme by the insurance-administrations is evaluated. Main criteria are the course of OD, job loss and costs of the procedures (follow-up 1 year). The random quota sample reveals the number of cases in which dermatological and/or preventive intervention were initiated by the administrations ("dermatologist's procedure"; N=995), in these cases patients and dermatologists involved are interviewed by a standardized questionnaire. In the remaining N=556 cases, no intervention has taken place so far; these cases are also analyzed. The study offers the unique opportunity to analyze the quality and interaction of dermatological and administrative procedures in the management of occupational dermatoses in Germany and to define criteria for further improvement.


Subject(s)
Dermatitis, Occupational/prevention & control , Dermatology/trends , Occupational Medicine/trends , Preventive Medicine/trends , Program Evaluation/trends , Randomized Controlled Trials as Topic/methods , Germany , Humans , Randomized Controlled Trials as Topic/trends
19.
Br J Dermatol ; 159(3): 621-7, 2008 Sep.
Article in English | MEDLINE | ID: mdl-18637008

ABSTRACT

BACKGROUND: Polymorphisms in the filaggrin (FLG) gene, which result in loss of filaggrin production, may alter the skin barrier and are a well-known predisposing factor for atopic dermatitis. OBJECTIVES: As a compromised skin barrier and atopic dermatitis are risk factors for chronic irritant contact dermatitis (CICD), our objective was to determine whether polymorphisms in the FLG gene contribute towards susceptibility to occupational CICD. METHODS: In a case-control study, the FLG polymorphisms R501X and 2282del4 were determined in 296 patients with CICD. Two hundred and seventeen apprentices in vocational training for high-risk occupations for CICD were chosen as controls. Data on skin diseases and conditions were collected by dermatologists from patients and by means of questionnaires from controls. RESULTS: Heterozygotes for R501X and 2282del4, FLG null alleles, were more frequent among patients with CICD (12.5%) compared with controls (6.9%), resulting in an odds ratio of 1.91 (95% confidence interval 1.02-3.59). Among patients who were carriers of a FLG null allele, we found a higher lifetime prevalence of flexural eczema (62% vs. 46%; P = 0.04) and a higher atopy score (13 vs. 10 points; P = 0.05) compared with noncarriers. In the apprentice group, signs of dermatitis before the start of the vocational training were four times more prevalent in carriers (43%) than in noncarriers (10%; P < 0.001). CONCLUSIONS: Our study shows that FLG null alleles are associated with increased susceptibility to CICD; whether or not the FLG null allele is an independent risk factor needs further study.


Subject(s)
Dermatitis, Irritant/genetics , Dermatitis, Occupational/genetics , Intermediate Filament Proteins/genetics , Polymorphism, Genetic , Adolescent , Adult , Case-Control Studies , Chi-Square Distribution , Child , Child, Preschool , Chronic Disease , Female , Filaggrin Proteins , Gene Expression , Gene Frequency , Genetic Predisposition to Disease , Humans , Infant , Male , Middle Aged
20.
IEEE Trans Med Imaging ; 27(4): 531-7, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18390349

ABSTRACT

An important problem of the analysis of functional magnetic resonance imaging (fMRI) experiments is to achieve some noise reduction of the data without blurring the shape of the activation areas. As a novel solution to this problem, recently the propagation-separation (PS) approach has been proposed. PS is a structure adaptive smoothing method that adapts to different shapes of activation areas. In this paper, we demonstrate how this method results in a more accurate localization of brain activity. First, it is shown in numerical simulations that PS is superior over Gaussian smoothing with respect to the accurate description of the shape of activation clusters and results in less false detections. Second, in a study of 37 presurgical planning cases we found that PS and Gaussian smoothing often yield different results, and we present examples showing aspects of the superiority of PS as applied to presurgical planning.


Subject(s)
Algorithms , Brain Mapping/methods , Brain Neoplasms/diagnosis , Brain Neoplasms/surgery , Imaging, Three-Dimensional/methods , Magnetic Resonance Imaging/methods , Pattern Recognition, Automated/methods , Humans , Image Enhancement/methods , Preoperative Care/methods , Reproducibility of Results , Sensitivity and Specificity
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