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Differentiation from Juvenile Arteriopathy

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Immunhistochemischer Nachweis des nicht-selektiven Kationenkanals TRPC6 im Skelettmuskelgewebe des Menschen

Hintergrund: Die im Plasmalemm bzw. Sarkolemm gelegenen TRPC6-Kanäle stellen nicht-selektive Kationenkanäle der TRP-Familie dar, die vor allem eine Permeabilität für das bivalente Calcium-Ion aufweisen. Ihr Vorkommen konnte bislang in tierischen, aber auch in menschlichen Geweben beschrieben werden. Insbesondere beim Menschen scheint TRPC6 eine Rolle bei der Pathophysiologie des ischämischen Schlaganfalls, sowie bei der Alzheimer Erkrankung zu spielen. Aber auch im Prozess der Kanzerogenese einiger Tumorentitäten scheinen sie beteiligt zu sein. Im renalen System wurde eine Assoziation zwischen einer Mutation des Kanals und der sogenannten Fokal-segmentalen Glomerulosklerose beschrieben, bei der es zum Defekt bis hin zum Untergang von Podozyten kommt. Ergebnisse aus tierischen Versuchsreihen zeigten seine wichtige Beteiligung im Prozess der malignen Hyperthermie. Auch im Sarkolemm von Skelettmuskelfasern der Maus konnte das Auftreten der Kanäle gezeigt und deren immense Bedeutung für den Kalziumeinstrom und letztlich für die muskuläre Funktion aufgezeigt werden. Des Weiteren lieferten wissenschaftliche Arbeiten Nachweise bzgl. der Expression von TRPC6 in der glatten Muskulatur des Menschen und dessen wichtige physiologische Bedeutung hinsichtlich der Funktionalität. Basierend auf dieser Grundlage, scheint das Vorhandensein der Kanäle im menschlichen Skelettmuskelgewebe somit nicht unwahrscheinlich. Zum Nachweis von TRPC6 in menschlichem Gewebe und insbesondere auch im menschlichen Skelettmuskelgewebe gibt es bislang kaum Daten. Daher war das Ziel dieser Arbeit, den immunhistochemischen Nachweis von TRPC6 in humanem Skelettmuskelgewebe zu erbringen. Methoden: Zur Durchführung der Studie wurden acht (n=8) Körperspender eingeschlossen. Die Entnahme der Gewebeproben der fixierten (n=6) und teilweise unfixierten (n=2) Spender realisierte man mittels dermatologischer Stanze und Skalpell aus den Mm. deltoideus, pectoralis major, trizeps brachii und rectus femoris. Aus den gewonnenen Proben konnten letztlich nach mehreren Arbeitsschritten histologische Schnittpräparate angefertigt werden, die dann zunächst zur Beurteilung der Struktur mit Hämatoxylin-Eosin angefärbt wurden. Zur Quantifizierung des Nachweises von TRPC6 im menschlichen Skelettmuskelgewebe wurde folglich die Immunhistochemie genutzt. Dabei kamen ein spezifischer Primärantikörper und ein enzymgekoppelter Sekundärantikörper zur Anwendung. Als Chromogen wurde Diaminobenzidin genutzt. Zur Spezifitätskontrolle wurde einmalig eine Peptidkontrolle durchgeführt, bei der der genutzte Primärantikörper mit einem Kontrollpeptid inkubiert wurde. Ergebnisse: Der Nachweis von TRPC6 im Skelettmuskelgewebe des Menschen konnte durch die genannte Methodik bestätigt werden. Alle im Rahmen einer Kreuzauswertung untersuchten Proben zeigten in der Immunhistochemie ein positives Signal, wenngleich dieses von unterschiedlicher Intensität war. Die einmalig durchgeführte Peptidkontrolle untermauerte das Ergebnis zudem. Sie führte zu einer deutlich abgeschwächten Bindung des Primärantikörpers an TRPC6. Schlussfolgerung: Der Nachweis von TRPC6 im humanem Skelettmuskelgewebe konnte mit dieser Arbeit erbracht werden. Das Wissen über das Vorhandensein der Kanäle im Gewebe der humanen Skelettmuskulatur bietet nun die Möglichkeit, die noch ungeklärte Funktion der nicht-selektiven Kationenkanäle hinsichtlich des Muskelstoffwechsels - gemeint ist der Stoffwechsel der humanen Skelettmuskulatur - weiter zu entschlüsseln. Aufgrund seiner allgemeinen Funktion scheint eine Beteiligung bei der Aufrechterhaltung der zellulären Calciumhomöostase nicht unwahrscheinlich. Ebenso könnte TRPC6 - neben seinem physiologischen Beitrag zur Funktionalität - im Rahmen pathophysiologischer Prozesse der Skelettmuskulatur eine bedeutende Rolle einnehmen, beachtet man beispielsweise Studien aus tierischen Versuchsreihen, bei denen dieser Zusammenhang gezeigt werden konnte. Damit könnte TRPC6 möglicherweise als Target pharmakologischer Substanzen dienen, die im Übrigen in anderen Geweben bereits Anwendung finden. Der Zusammenhang zwischen den nicht-selektiven Kationenkanälen TRPC6 und den zahlreichen Erkrankungen der Skelettmuskulatur bleiben zunächst ein unzureichend entschlüsseltes Konstrukt. Es bedarf weiterer wissenschaftlicher Arbeiten, um diese Komplexität zu entschlüsseln.Background: TRPC6 channels constitute non-selective cation channels that are localized in plasmalemm respectively sarcolemm and have a leading permeability for the bivalent calcium ion. Until now it was found in animal as well as in human tissues. In humans the channel seems to play an important role when it comes to the pathophysiology of cerebral ischemia or Alzheimer´s disease. They seem also to be involved in cancerogenesis. With regard to renal system there are described associations between TRPC6 and the focal segmental glomerulosclerosis that leads to a deficiency or a destruction of podocytes. Furthermore, results of animal experiments could show an involvement of the transient receptor potential channel 6 in a condition known as malignant hyperthermia. In skeletal muscle fibers of mice the expression of TRPC6 in the sarcolemm could be shown. Their enormous importance for the influx of calcium into the muscle cell and thus for the muscular function could also be revealed. Furthermore, some research groups revealed the expression of TRPC6 in human smooth muscle cells and the important role for its function. Based on this foundation the presence of the transient receptor potential channel 6 in human skeletal muscle does not seem unlikely. So far, there is hardly any data on the detection of TRPC6 in human tissue and, in particular, in human skeletal muscle tissue. Therefore, the aim of this work was to provide the immunohistochemical detection of TRPC6 in human skeletal muscle tissue. Methods: For this study eight (n=8) human donors were included. The removal of the tissue was realized by a biopsy punch and a scalpel from the Mm. deltoideus, pectoralis major, trizeps brachii and rectus femoris. The donors were in fixed (n=6) and partially unfixed (n=2) conditions. The samples obtained were processed into histological sections, which were then subjected to Hämatoxylin-Eosin staining. To quantify the detection of TRPC6 in human skeletal muscle tissue we used Immunohistochemistry. Therefore, a primary and an enzyme-linked secondary antibody were used. Diaminobenzidine was used as the chromogenic substrate. In order to specify the result, we processed a peptide incubation of the primary antibody once. Result: The detection of TRPC6 in human skeletal muscle was confirmed by using Immunohistochemistry. All samples examined has shown a positive signal in the IHC, although this was of varying intensity. The peptide control also confirmed the result. The use of the control peptide resulted in a weakened or rather in an absent binding of the primary antibody on the TRPC6 protein. Conclusion: With this research we were able to provide the expression of TRPC6 protein in human skeletal muscle the first time. Based on this foundation following researches may help to understand the unknown function of the non-selective cation channels for the human skeletal muscle metabolism. Its general function suggests that it may be involved in the maintenance of the intracellular calcium homeostasis. Furthermore, they could also be involved in pathophysiological processes as shown in animal experiments. If associations between TRPC6 and muscle diseases could be established, the channels could also serve as a pharmacological target in the future. In summary the association between the transient receptor potential channel 6 and the numerous muscle diseases remain elusive. There are more investigations needed for clarification

Tourette syndrome and nutritional implications

Gilles de la Tourette syndrome (GTS) is a neurodevelopmental disorder defined by multiple motor tics and at least one sound tic. Various behavioural symptoms are associated with GTS, especially obsession and compulsion behaviours (OCBs), attention-deficit/hyperactivity disorder (ADHD) and poor impulse control. These comorbid conditions have a high impact on patients quality of life, including eating attitudes and body image perception. Nutritional implications, together with sleepiness and sexual asthenia, are the principal side effects of the pharmacological therapy. Actually, drugs may compromise the nutritional status of patients producing appetite increase, dry mouth, constipation, glucose and lipid metabolism abnormalities, metabolic syndrome, mild transient dysphagia and nausea. About 40% of GTS patients experience hyperphagia because of drug side effects, OCBs, ADHD, or poor impulse control. Consequently, in these cases an overweight status can occur, complicating the management of the symptoms. Therefore, an increase body weight should be considered one of the most relevant factors increasing GTS drug-related bad compliance, which may consequently cause in some patients the discontinuation/interruption of the pharmacological therapy

Estimating Postmortem Interval Using VNIR Spectroscopy on Human Cortical Bone

Postmortem interval (PMI) estimation is a necessary but often difficult task that must completed during a death investigation. The level of difficulty rises as time since death increases, especially with the case of skeletonized remains (long PMI). While challenging, a reliable PMI estimate may be of great importance for investigative direction and cost-savings (e.g. suspect identification, tailoring missing persons searches, non-forensic remains exclusion). Long PMI can be estimated by assessing changes in the organic content of bone (i.e. collagen), which degrades and is lost as the PMI lengthens. Visible-near infrared (VNIR) spectroscopy is one method that can be used for analyzing organic constituents, including proteins, in solid specimens. A 2013 preliminary investigation using a limited number of human cortical bone samples suggested that VNIR spectroscopy could provide a fast, reliable technique for assessing PMI in human skeletal remains. Clear separation was noted between "forensic" and "archaeological" specimen spectra within the near-infrared (NIR) bands. The goal of this research was to develop reliable multivariate classification models that could assign skeletal remains to appropriate PMI classes (e.g. "forensic" and "non-forensic"), based on NIR spectra collected from human cortical bone. Working with a large set of cortical samples (n=341), absorbance spectra were collected with an ASD/PANalytical LabSpec® 4 full range spectrometer. Sample spectra were then randomly assigned to training and test sets, where training set spectra were used to build internally cross-validated models in Camo Unscrambler® X 10.4; external validations of the models were then performed on test set spectra. Selected model algorithms included soft independent modeling of class analogy (SIMCA), linear discriminant analysis on principal components (LDA-PCA), and partial least squares discriminant analysis (PLSDA); an application of support vector machines on principal components (SVM-PCA) was attempted as well. Multivariate classification models were built using both raw and transformed spectra (standard normal variate, Savitzky-Golay) that were collected from the longitudinally cut cortical surfaces (Set A models) and the superficial cortical surface following light grinding (Set B models). SIMCA models were consistently the poorest performers, as were many of the SVM-PCA models; LDA-PCA models were generally the best performers for these data. Transformed-spectra model classification accuracies were generally the same or lower than corresponding raw spectral models. Set A models out-performed Set B counterparts in most cases; Set B models often yielded lower classification accuracy for older forensic and non-forensic spectra. A limited number of Set B transformed-spectra models out-performed the raw model counterparts, suggesting that these transformations may be removing scattering-related noise, leading to improvements in model accuracy. This study suggests that NIR spectroscopy may represent a reliable technique for assessing the PMI of unknown human skeletal remains. Future work will require identifying new sources of remains with established extended PMI values. Broadening the number of spectra collected from older forensic samples would allow for the determination of how many narrower potential PMI classes can be discriminated within the forensic time-frame

Thermal Identification of Clandestine Burials: A Signature Analysis and Image Classification Approach

Clandestine burials, the interred human remains of forensic interest, are generally small features located in isolated environments. Typical ground searches can be both time-consuming and dangerous. Thermal remote sensing has been recognized for some time as a possible search strategy for such burials that are in relatively open areas; however, there is a paucity of published research with respect to this application. This project involved image manipulation, the analyses of signatures for "graves" of various depths when compared to an undisturbed background, and the use of image classification techniques to tease out these features. This research demonstrates a relationship between the depth of burial disturbance and the resultant signature. Further, image classification techniques, especially object-oriented algorithms, can be successfully applied to single band thermal imagery. These findings may ultimately decrease burial search times for law enforcement and increase the likelihood of locating clandestine graves

Considerações acerca da pesquisa sociológica: o materialismo histórico hoje e suas implicações no debate científico contemporâneo

Este artigo procura refletir sobre a atualidade do materialismo histórico, debatendo com outras correntes metodológicas que acreditam que ele não mais é viável nos dias de hoje

Electrode displacement after intracerebral hematoma as a complication of a deep brain stimulation procedure

Domenico Servello1, Marco Sassi1, Stefano Bastianello2, Guy Umberto Poloni2, Francesca Mancini3, Claudio Pacchetti31Functional Neurosurgery Unit, Istituto di Ricovero e Cura a Carattere Scientifico Galeazzi, Milan, Italy; 2Neuroradiology Unit; 3Parkinson Disease and Movement Disorder Unit, Istituto di Ricovero e Cura a Carattere Scientifico Mondino, Institute of Neurology, Pavia, Italy Objectives: Deep brain stimulation (DBS) is nowadays considered a safe and effective procedure for various movement disorders in which conservative treatments have failed to show significant therapeutic results. One of the most common complications of definitive electrode positioning is intraparenchymal hemorrhage.Materials and methods: Authors report the case of a 55-year-old female patient treated for Parkinson’s disease in which intraparenchymal hemorrhage developed after DBS procedure, leading to significant (about 8 mm at the neuroradiological controls) displacement of an otherwise correctly positioned DBS electrode.Results: After conservative management, the hematoma spontaneously resolved. Late neuroradiological controls documented correct, symmetrically positioned electrodes, comparable to the immediate postoperative controls.Conclusions: Six months follow-up endpoint results of the DBS treatment were considered satisfying by an independent neurologist, with modest residual neurological deficits, demonstrating that re-positioning of the electrode was unnecessary in this rare complication.Keywords: deep brain stimulation, electrodes, outcomes, implant, case repor

The Relationship of Nutritional Factors to Apple Tree Root Damage by Pine Voles

Damage to apple tree roots by pine voles is believed to occur primarily during the winter months. Cengel et a1. (1978) found that the stomachs of pine voles contained significant amounts of root material only during January and March sampling periods. In addition, the diet of pine voles at that time consisted primarily of less preferred grass species because preferred forb species were unavailable. Therefore, apple tree roots may serve as a food source in the winter when preferred forages are unavailable. If, in fact, pine voles are consuming roots in response to reduced food supplies, then one would expect the nutritional quality of the diets of pine voles to be its lowest during the winter. The objective of this study was to determine if there was a winter decline in the digestibility of the diet of the pine vole