771 resultados para skull ontogeny


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Treatment of spinal fracture and luxation in small animals Traumatic spinal injuries usually result from a mechanic trauma. Spinal facture and luxations generally occur in the junction between and more mobile parts of the spinal column: close to the skull, thorax and pelvis. Fractures may occur alone or in combination with luxation as fracture/luxation. When the fractures are not stable the best solution is the surgical fixation. Internal and external fixation are the surgical methods for the treatment of vertebral fractures and luxations. The authors report the treatment of 12 cases of thoracic and lumbar vertebral fractures and luxations in small animals using the screws/pins and Polymethylmethacrylate technique. The analysis of results is a contribute I the valutation of surgical technique and complications in the post-surgical period.

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The horizontal and vertical system neurons (HS and VS cells) are part of a conserved set of lobula plate giant neurons (LPGNs) in the optic lobes of the adult brain. Structure and physiology of these cells are well known, predominantly from studies in larger Dipteran flies. Our knowledge about the ontogeny of these cells is limited and stems predominantly from laser ablation studies in larvae of the house fly Musca domestica. These studies suggested that the HS and VS cells stem from a single precursor, which, at least in Musca, has not yet divided in the second larval instar. A regulatory mutation (In(1)omb[H31]) in the Drosophila gene optomotor-blind (omb) leads to the selective loss of the adult HS and VS cells. This mutation causes a transient reduction in omb expression in what appears to be the entire optic lobe anlage (OLA) late in embryogenesis. Here, I have reinitiated the laser approach with the goal of identifying the presumptive embryonic HS/VS precursor cell in Drosophila. The usefulness of the laser ablation approach which has not been applied, so far, to cells lying deep within the Drosophila embryo, was first tested on two well defined embryonic sensory structures, the olfactory antenno-maxillary complex (AMC) and the light-sensitive Bolwing´s organ (BO). In the case of the AMC, the efficiency of the ablation procedure was demonstrated with a behavioral assay. When both AMCs were ablated, the response to an attractive odour (n-butanol) was clearly reduced. Interestingly, the larvae were not completely unresponsive but had a delayed response kinetics, indicating the existence of a second odour system. BO will be a useful test system for the selectivity of laser ablation when used at higher spatial resolution. An omb-Gal4 enhancer trap line was used to visualize the embryonic OLA by GFP fluorescence. This fluorescence allowed to guide the laser beam to the relevant structure within the embryo. The success of the ablations was monitored in the adult brain via the enhancer trap insertion A122 which selectively visualizes the HS and VS cell bodies. Due to their tight clustering, individual cells could not be identified in the embryonic OLA by conventional fluorescence microscopy. Nonetheless, systematic ablation of subdomains of the OLA allowed to localize the presumptive HS/VS precursor to a small area within the OLA, encompassing around 10 cells. Future studies at higher resolution should be able to identify the precursor as (an) individual cell(s). Most known lethal omb alleles do not complement the HS/VS phenotype of the In(1)omb[H31] allele. This is the expected behaviour of null alleles. Two lethal omb alleles that had been isolated previously by non-complementation of the omb hypomorphic allele bifid, have been reported, however, to complement In(1)omb[H31]. This report was based on low resolution paraffin histology of adult heads. Four mutations from this mutagenesis were characterized here in more detail (l(1)omb[11], l(1)omb[12], l(1)omb[13], and l(1)omb[15]). Using A122 as marker for the adult HS and VS cells, I could show, that only l(1)omb[11] can partly complement the HS/VS cell phenotype of In(1)omb[H31]. In order to identify the molecular lesions in these mutants, the exons and exon/intron junctions were sequenced in PCR-amplified material from heterozygous flies. Only in two mutants could the molecular cause for loss of omb function be identified: in l(1)omb[13]), a missense mutation causes the exchange of a highly conserved residue within the DNA-binding T-domain; in l(1)omb[15]), a nonsense mutation causes a C-terminal truncation. In the other two mutants apparently regulatory regions or not yet identified alternative exons are affected. To see whether mutant OMB protein in the missense mutant l(1)omb[13] is affected in DNA binding, electrophoretic shift assays on wildtype and mutant T-domains were performed. They revealed that the mutant no longer is able to bind the consensus palindromic T-box element.

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In the marine Jurassic deposits of Europe, a group of marine crocodilians, the Thalattosuchia, belongs to the frequently found reptiles. Thalattosuchia are widely spread in Central Europe from the Jurassic to Lower Cretaceous, and some taxa are also distributed worldwide. The task of the work was to examine all taxa known from the Liassic of Europe. The most frequently known taxa Steneosaurus bollensis and Pelagosaurus typus are anatomically revised. New discoveries at the skull of Pelagosaurus typus e.g., the fact of a partly paired frontal are described by means of computed tomography investigations. In addition, juvenile specimens of this taxon are studied in detail for the first time. The rarely occurring taxon Platysuchus multiscrobiculatus is anatomically described in detail for the first time. It shows both in the skull and in the postcranial material morphological differences to Steneosaurus bollensis and Pelagosaurus typus. Thus Pl. multiscrobiculatus possesses, e.g., an ilium with a deeper acetabulum and a femur with a distinctly flexed femoral head. A juvenile specimen of Pl. multiscrobiculatus is now discovered and is described in parts for the first time, too. Furthermore, Steneosaurus gracilirostris and Steneosaurus brevior known from Lower Jurassic deposits of England are examined and in parts revised. In this work, Steneosaurs brevior is discovered with one specimen from the Upper Liassic of Holzmaden, Germany for the first time, and provides new evidence for the palaeobiogeographical distribution of the taxon. Because of the high number of investigated specimens, it is possible to study ontogenetic development from juvenile to adult stage in Steneosaurus bollensis, Pelagosaurus typus, and Platysuchus multiscrobiculatus. Biometric data are collected from thalattosuchians and extant crocodilians (e.g. Gavialis gangeticus) to investigate intraspecific variation, ontogenetic development, and taxa differentiation. The skulls of Platysuchus multiscrobiculatus and Steneosaurus bollensis are reconstructed three-dimensionally as wax models. The skull reconstructions form the basis of the jaw muscle restoration of Steneosaurus bollensis in connection with comparative studies at extant crocodilians. By means of functional morphologic analysis of the jaw musculature, the dentition, and the locomotor system of S. bollensis, possible conclusions are drawn for the prey options and the hunting behaviour. To clarify the relationships within the Thalattosuchia, a computer-based cladistic phylogenetic in-group analyse of 25 Thalattosuchia taxa is performed. For the analysis, following Thalattosuchia taxa are studied likewise at original material for comparisons: Metriorhynchus superciliosus, Metriorhynchus hastifer, Metriorhynchus leedsi, Geosaurus gracilis, Geosaurus giganteus, Teleidosaurus calvadosi, Teleidosaurus gaudryi, Teleosaurus cadomensis, Teleosaurus geoffroyi, Steneosaurus priscus, Steneosaurus edwardsi, Steneosaurus heberti, Steneosaurus leedsi, Steneosaurus boutilieri, Steneosaurus megarhinus, Steneosaurus obtusidens, and Machimosaurus hugii. The phylogenetic in-group analyse based on 115 characters, reveals a sister-group relationship of the monophyletic Teleosauridae and monophyletic Metriorhynchidae. Within the groups, some taxa are probably paraphyletic. The taxon Pelagosaurus typus is nested inside the Teleosauridae and not outside or within the Metriorhynchidae, as many authors suggested it so far. Based on these results, a tentative palaeobiogeographical-evolutionary scenario is developed.

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La sindrome di Noonan (SN) è una patologia a trasmissione autosomica dominante caratterizzata da bassa statura, difetti cardiaci congeniti, dismorfia facciale. In letteratura sono stati pubblicati pochi case reports riguardanti le condizioni orali-facciali in pazienti affetti da SN. Obiettivo. Individuare patologie di pertinenza ortopedico-ortodontica caratteristiche della sindrome utilizzando un campione di pazienti con diagnosi di SN. Metodi. Un gruppo di 10 pazienti affetti da SN è stato sottoposto a esame obiettivo extraorale ed intraorale, ortopantomografia, teleradiografia latero-laterale, impronte delle arcate dentarie. Le misurazioni sulle TLL sono state effettuate sulla base dell'analisi MBT; i valori palatali provengono dai modelli di studio dell’arcata superiore. È stata utilizzato il test t-Student per mettere a confronto il gruppo di studio e il gruppo di controllo riguardo le misure cefalometriche e i valori palatali. Risultati. Nel gruppo di studio sono state rilevate anomalie di numero (un dente deciduo soprannumerario e una agenesia di un dente permanente). Il test t-Student rivela differenze statisticamente significative per 7 variabili cefalometriche su 13 e per 2 variabili palatali. Conclusioni. Basandosi su questo studio è possibile concludere che i pazienti con SN mostrano II classe scheletrica di tipo mandibolare, crescita iperdivergente, tendenza al morso aperto scheletrico, palatoversione degli incisivi superiori, palato stretto. Questi risultati possono fornire informazioni utili sia per la diagnosi di SN sia per la pianificazione del corretto trattamento ortodontico.

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In questa tesi sono illustrate alcune sperimentazioni finalizzate alla standardizzazione del ciclo produttivo della sogliola comune (Solea solea) in cattività. E’ stato creato un parco di riproduttori selvatici ed è stata standardizzata la riproduzione ad un livello compatibile con la realtà produttiva del settore. Indagini genetiche di assegnazione parentale hanno evidenziato come alcuni esemplari siano stati predominanti negli accoppiamenti e nel conseguente contributo alla generazione della prole. Ciò ha determinato una diminuzione della variabilità genetica dei discendenti. La composizione quali-quantitativa degli acidi grassi delle uova è stata correlata con la sopravvivenza larvale nel corso di un’intera stagione riproduttiva. Tale composizione non ha subito importanti variazioni su scala temporale e sembra essere stata influenzata dall’alimentazione somministrata ai riproduttori nel periodo precedente alla riproduzione. Le analisi di interazione tra momento riproduttivo e qualità delle uova hanno confermato che è stato possibile ottenere uova di buona qualità in termini di sopravvivenza larvale nel corso di tutta la stagione riproduttiva. Larve di sogliola sono state svezzate precocemente 13 giorni dopo la schiusa riducendo l’impiego di cibo vivo a favore di micro diete commerciali. Tale svezzamento ha ridotto le performance di accrescimento, ma non la sopravvivenza e lo sviluppo della metamorfosi quando comparati ad un trattamento standard. La riduzione del cibo vivo ha ottimizzato i costi di produzione e migliorato l’igiene in vasca. L’ontogenesi di precursori di enzimi digestivi è stata determinata tramite PCR quantitativa. I risultati di espressione di tripsinogeno, chimotripsinogeno e amilasi hanno mostrato come tali enzimi rivestano un ruolo chiave nei processi digestivi delle prime fasi larvali. Esemplari giovanili hanno ottenuto un significativo maggiore indice di accrescimento e migliore indice di conversione quando alimentati con diete sperimentali contenenti un elevato tenore proteico. Un aumento dell’incidenza di vacuoli lipidici a livello epatico è stato osservato all’aumentare del tenore proteico della dieta.

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Form und Gestalt kraniofazialer Strukturen sind primär beeinflusst durch die inhärente Integration der unterschiedlichsten Funktionssysteme und externer selektiver Einflüsse. Die Variabilität der Schädel-Morphe ist ein Indikator für solche Einflussfaktoren und damit ein idealer Gegenstand für vergleichende Analysen morphogenetischer Formbildung. Zur Ermittlung morphologisch-adaptiver Trends und Muster wurden sowohl Hypothesen zur morphologischen Differenziertheit als auch zu Korrelationen zwischen modularen Schädelkompartimenten (fazial, neurokranial, basikranial) untersucht. Zusätzlich wurden aus Schichtröntgenaufnahmen (CT) virtuelle Modelle rekonstruiert, welche die Interpretation der statistischen Befunde unterstützen sollten. Zur Berechnung der Gestaltunterschiede wurden mittels eines mechanischen Gelenkarm-Messgerätes (MicroScribe-G2) max. 85 ektokraniale Messpunkte (Landmarks) bzw. dreidimensionale Koordinaten an ca. 520 Schädeln von fünf rezenten Gattungen der Überfamilie Hominoidea (Hylobates, Pongo, Gorilla, Pan und Homo) akquiriert. Aus dem Datensatz wurden geometrische Störfaktoren (Größe, Translation, Rotation) mathematisch eliminiert und die verbleibenden Residuale bzw. ‚Gestalt-Variablen‘ diversen multivariat-statistischen Verfahren unterzogen (Faktoren, Cluster-, Regressions- und Korrelationsanalysen sowie statistische Tests). Die angewandten Methoden erhalten die geometrische Information der Untersuchungsobjekte über alle Analyseschritte hinweg und werden unter der Bezeichnung „Geometric Morphometrics (GMM)“ als aktueller Ansatz der Morphometrie zusammengefasst. Für die unterschiedlichen Fragestellungen wurden spezifische Datensätze generiert. Es konnten diverse morphologische Trends und adaptive Muster mit Hilfe der Synthese statistischer Methoden und computer-basierter Rekonstruktionen aus den generierten Datensätzen ermittelt werden. Außerdem war es möglich, präzise zu rekonstruieren, welche kranialen Strukturen innerhalb der Stichprobe miteinander wechselwirken, einzigartige Variabilitäten repräsentieren oder eher homogen gestaltet sind. Die vorliegenden Befunde lassen erkennen, dass Fazial- und Neurokranium am stärksten miteinander korrelieren, während das Basikranium geringe Abhängigkeiten in Bezug auf Gesichts- oder Hirnschädelveränderungen zeigte. Das Basikranium erweist sich zudem bei den nicht-menschlichen Hominoidea und über alle Analysen hinweg als konservative und evolutiv-persistente Struktur mit dem geringsten Veränderungs-Potential. Juvenile Individuen zeigen eine hohe Affinität zueinander und zu Formen mit einem kleinem Gesichts- und großem Hirnschädel. Während das Kranium des rezenten Menschen primär von Enkephalisation und fazialer Retraktion (Orthognathisierung) dominiert ist und somit eine einzigartige Gestalt aufweist, zeigt sich der Kauapparat als maßgeblich formbildendes Kompartiment bei den nicht-menschlichen Formen. Die Verbindung von GMM mit den interaktiven Möglichkeiten computergenerierter Modelle erwies sich als valides Werkzeug zur Erfassung der aufgeworfenen Fragestellungen. Die Interpretation der Befunde ist durch massive Interkorrelationen der untersuchten Strukturen und der statistisch-mathematischen Prozeduren als hoch komplex zu kennzeichnen. Die Studie präsentiert einen innovativen Ansatz der modernen Morphometrie, welcher für zukünftige Untersuchungen im Bereich der kraniofazialen Gestaltanalyse ausgebaut werden könnte. Dabei verspricht die Verknüpfung mit ‚klassischen’ und modernen Zugängen (z. B. Molekularbiologie) gesteigerte Erkenntnismöglichkeiten für künftige morphometrische Fragestellungen.

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This thesis presents a comparative developmental study of inflorescences and focuses on the production of the terminal flower (TF). Morphometric attributes of inflorescence meristems (IM) were obtained throughout the ontogeny of inflorescence buds with the aim of describing possible spatial constraints that could explain the failure in developing the TF. The study exposes the inflorescence ontogeny of 20 species from five families of the Eudicots (Berberidaceae, Papaveraceae-Fumarioideae, Rosaceae, Campanulaceae and Apiaceae) in which 745 buds of open (i.e. without TF) and closed (i.e. with TF) inflorescences were observed under the scanning electron microscope.rnThe study shows that TFs appear on IMs which are 2,75 (se = 0,38) times larger than the youngest lateral reproductive primordium. The shape of these IMs is characterized by a leaf arc (phyllotactic attribute) of 91,84° (se = 7,32) and a meristematic elevation of 27,93° (se = 5,42). IMs of open inflorescences show a significant lower relative surface, averaging 1,09 (se=0,26) times the youngest primordium size, which suggests their incapacity for producing TFs. The relative lower size of open IMs is either a condition throughout the complete ontogeny (‘open I’) or a result from the drastic reduction of the meristematic surface after flower segregation (‘open II’). rnIt is concluded that a suitable bulge configuration of the IM is a prerequisite for TF formation. Observations in the TF-facultative species Daucus carota support this view, as the absence of the TF in certain umbellets is correlated with a reduction of their IM dimensions. A review of literature regarding histological development of IMs and genetic regulation of inflorescences suggests that in ‘open I’ inflorescences, the histological composition and molecular activity at the tip of the IM could impede the TF differentiation. On the other side, in ‘open II’ inflorescences, the small final IM bulge could represent a spatial constraint that hinders the differentiation of the TF. The existence of two distinct kinds of ontogenies of open inflorescences suggests two ways in which the loss of the TF could have occurred in the course of evolution.rn

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Der Forschungsgegenstand der vorliegenden Arbeit war die Identifikation und Interpretation von Traumata an menschlichen Skeletten. Neben einer umfassenden Darstellung des aktuellen Kenntnisstandes unter verschiedenen Gesichtspunkten wurden menschliche Überreste aus der Schlacht von Dornach 1499 n. Chr. untersucht. Ergänzend wurde eine Versuchsreihe mit Replika mittelalterlicher Waffen an Kunstköpfen durchgeführt. Für die Ansprache und Kategorisierung von Traumata an Skelettfunden existiert kein einheitliches und allgemein gebräuchliches System. Die verschiedenen Herangehensweisen und ihre Vor- und Nachteile wurden benannt und diskutiert. Nachfolgend wurden die Erscheinungsformen prä-, peri- und postmortaler Traumata bzw. Defekte sowie von Verletzungen durch stumpfe und scharfe Gewalt, Schussverletzungen und anderen Verletzungsarten dargestellt. Weitere besprochene Aspekte waren die Abgrenzung von Traumata gegen pathologische Veränderungen und anatomische Varianten sowie eine Diskussion der Methodik und Problematik der Erfassung von Verletzungsfrequenzen. Neben der Bestimmung von Geschlecht, Sterbealter und Körperhöhe wurden an den zur Untersuchung zur Verfügung stehenden Schädeln (N=106) und Femora (N=33) aus der Schlacht von Dornach 1499 n. Chr. pathologische und postmortale Veränderungen sowie als Schwerpunkt prä- und perimortale Traumata identifiziert und beschrieben. Die anthropologischen Befunde zeichneten das Bild einer in Hinsicht auf Sterbealter und Körperhöhe heterogenen Gruppe von Männern mit wenigen pathologischen Veränderungen. Die Ergebnisse wurden vor dem Hintergrund des spätmittelalterlichen Söldnerwesens diskutiert. An den Schädeln wurden insgesamt 417 perimortale Traumata identifiziert, wobei Hiebverletzungen stark überwogen. Die Entstehungsweise charakteristischer Merkmale von Hiebverletzungen konnte experimentell nachvollzogen werden. Weiter stellte sich heraus, dass Hiebverletzungen durch Schwerter und Hellebarden nur in Ausnahmefällen voneinander unterschieden werden können. Verletzungen durch punktuelle Einwirkungen und stumpfe Gewalt sowie Schussverletzungen wurden in weitaus geringerer Häufigkeit festgestellt. Experimentell konnte gezeigt werden, dass die Verletzungen durch punktuelle Einwirkungen mit einer Beibringung durch Langspiesse, Stossspitzen und Reisshaken von Hellebarden sowie Armbrustbolzen vereinbar sind, wobei beträchtliche Limitationen einer genaueren Waffenzuordnung offenkundig wurden. Die Verletzungen konnten als wohl typisch für die damalige Zeit bezeichnet werden, da sie das zeitgenössische Waffenspektrum deutlich widerspiegeln. Die Lokalisation der perimortalen Traumata am Schädel liess kein Muster erkennen, mit Ausnahme der Feststellung, dass grössere Schädelknochen mehr Verletzungen aufwiesen als kleinere. Diese regellose Verteilung wurde als Hinweis darauf verstanden, dass die Kampfweise keine „ritterliche“ gewesen sein dürfte, was in Einklang mit den damals geltenden Kriegsordnungen steht. Postmortale Veränderungen unterschiedlicher Art liessen vermuten, dass die untersuchten Individuen nicht bestattet wurden und dass die vom Schlachtfeld aufgesammelten Gebeine in Beinhäusern aufbewahrt wurden. Die Resultate bestätigten damit Angaben aus Schriftquellen und erlaubten die Zuordnung der Skelettreste zu Gefallenen des Reichsheeres. Beim Vergleich der Dornacher Stichprobe mit anderen mittelalterlichen Schlachtfeldserien traten sowohl hinsichtlich der anthropologischen Befunde als auch im Hinblick auf die Verletzungen und Verletzungsmuster deutliche Ähnlichkeiten zutage. Diese ergänzten nicht nur das lückenhafte Bild spätmittelalterlicher Heere und ihrer Kampfweise, sondern beleuchteten auch Unterschiede zwischen mittelalterlicher und neuzeitlicher Kriegsführung.

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Chromosomal and genetic syndromes are frequently associated with dental and cranio-facial alterations. The aim of our study is to identify and describe the dental and craniofacial alterations typical of six genetic and chromosomal syndromes examined. Materials and Methods- A dental visit was performed to 195 patients referred from Sant’Orsola Hospital of Bologna, University of Bologna, to Service of Special Need Dentistry, Dental Clinic, Department of Biomedical and Neuromotor Science, University of Bologna. The patients recruited were 137 females and 58 males, in an age range of 3-49 years (mean age of 13.8±7.4). The total sample consisted of subjects affected with Down Syndrome (n=133), Familiar Hypophosphatemic Ricket (n=10), Muscular Dystrophies (n=12), Noonan Syndrome (n=13), Turner Syndrome (n=17), Williams Syndrome(n=10). A questionnaire regarding detailed medical and dental history, oral health and dietary habits, was filled by parents/caregivers, or patients themselves when possible. The intra-oral and extra-oral examination valued the presence of facial asymmetries, oral habits, dental and skeletal malocclusions, dental formula, dental anomalies, Plaque Index (Silness&LÖe Index), caries prevalence (dmft/DMFT index), gingivitis and periodontal disease, and mucosal lesions. Radiographic examinations (Intraoral radiographies, Orthopanoramic, Skull teleradiography) were executed according to patient’s age and treatment planning. A review of literature about each syndrome and its dental and cranio-facial characteristics and about caries, hygiene status and malocclusion prevalence on syndromic and non-syndromic population was performed. Results - The data of all the patients were collected in the “Data Collection Tables” created for each syndrome. General anamnesis information, oral hygiene habits and dmft/DMFT, PI, malocclusion prevalence were calculated and compared to syndromic and non-syndromic population results found in literature. Discussions and conclusions - Guidelines of Special Care dentistry were indicated for each syndrome, in relation to each syndrome features and individual patient characteristics.

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ZusammenfassungrnAlle bekannten Exemplare der Amphibien-Gruppe Microsauria des mitteleuropäischen Rotliegend wurden untersucht sowie – für die kladistische Untersuchung – ihre nächsten Verwandten. Im Saar-Nahe-Becken sind vier Arten aus zwei Microsauria-Gattungen nachzuweisen: Batropetes niederkirchensis n. sp., Batropetes palatinus n. sp., Batropetes appelensis n. sp. und Altenglanerpeton schroederi n. sp.. Aus dem Döhlen-Becken bei Dresden stammt Batropetes fritschi.rnDie Rekonstruktionen legen nahe, dass die in Seeablagerungen gefundenen Batropetes-Arten kleine, terrestrisch lebende Microsaurier waren, die sich von Insekten oder deren Larven ernährten. Ihre mittlere Gesamtlänge beträgt fast 8 cm, ihr Rumpf ist auffallend kurz mit je nach Art 17 oder 19 Präsakralwirbeln. Sie besitzen große von Wülsten umgebene Augenöffnungen, ein großes Pinealforamen, drei längs angeordnete Grübchen auf den Frontalia, dreispitzige Zähne, einen zahnlosen Gaumen und vier kurze kräftige Extremitäten. Becken- und Schultergürtel sind komplett verknöchert, außer den bei Batropetes appelensis und Batropetes fritschi knorpeligen Coracoid-Anteilen. Die Batropetes-Arten unterscheiden sich bezüglich Form, Proportionen bzw. Verknöcherungsgrad einiger Knochen im cranialen und postcranialen Skelett. rnDie kladistischen Untersuchungen ergeben für die Arten der monophyletische Gattung Batropetes, dass Batropetes appelensis den übrigen Arten gegenübersteht und Batropetes palatinus mit Batropetes fritschi eine Schwestergruppe zu Batropetes niederkirchensis bildet. Mit den etwas jüngeren texanischen Gattungen Carrolla und Quasicaecilia bildet Batropetes die monophyletische Familie Brachystelechidae. rnAltenglanerpeton schroederi, nur durch ein schlecht erhaltenes Exemplar überliefert, besitzt einen massiv gebauten Schädel, kaum länger als breit mit annähernd dreieckigem Umriss, ohne Anzeichen für Seitenlinien, mit kleiner rundlicher Orbita, sehr breiter Interorbitalregion und bis weit vor die Orbita reichendem Jugale. Sein langer Rumpf umfasst mindestens 30 lepospondyle Präsakralwirbel. Wegen der unvollkommenen Entwicklung der Gliedmaßen kann diese Art nicht auf vier Beinen gelaufen sein und lebte möglicherweise in der Laubschicht wühlend oder in Sümpfen. Altenglanerpeton ist keiner bestimmten Microsauria-Familie zuzuordnen und steht den Pantylidae, Gymnarthridae, Goniorhynchidae und Ostodolepidae am nächsten, wobei zu letzteren die meisten morphologischen Ähnlichkeiten bestehen.rnAußerdem sind mit isolierten Einzelknochen, insbesondere Wirbeln, Microsauria und andere Gruppen lepospondyler Amphibien ohne Bestimmung der Gattung und Art aus wenigen stratigraphischen Niveaus des Saar-Nahe-Beckens überliefert. rn

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The purpose of this study was to evaluate whether measurements on conventional cephalometric radiographs are comparable with 3D measurements on 3D models of human skulls, derived from cone beam CT (CBCT) data. A CBCT scan and a conventional cephalometric radiograph were made of 40 dry skulls. Standard cephalometric software was used to identify landmarks on both the 2D images and the 3D models. The same operator identified 17 landmarks on the cephalometric radiographs and on the 3D models. All images and 3D models were traced five times with a time-interval of 1 week and the mean value of repeated measurements was used for further statistical analysis. Distances and angles were calculated. Intra-observer reliability was good for all measurements. The reproducibility of the measurements on the conventional cephalometric radiographs was higher compared with the reproducibility of measurements on the 3D models. For a few measurements a clinically relevant difference between measurements on conventional cephalometric radiographs and 3D models was found. Measurements on conventional cephalometric radiographs can differ significantly from measurements on 3D models of the same skull. The authors recommend that 3D tracings for longitudinal research are not used in cases were there are only 2D records from the past.

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Craniosynostosis consists of a premature fusion of the sutures in an infant skull, which restricts the skull and brain growth. During the last decades there has been a rapid increase of fundamentally diverse surgical treatment methods. At present, the surgical outcome has been assessed using global variables such as cephalic index, head circumerence and intracranial volume. However, the variables have failed in describing the local deformations and morphological changes, which are proposed to more likely induce neurological disorders.

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Hatchet blows to the human skull often cause fatal injuries. We present a case of homicide by hatchet blow that underwent CT, MRI, and autopsy examination. Skull fragmentation, fracture lines, and brain injuries were demonstrated prior to autopsy. Many of the hatchet-specific characteristics (flaking, crushing, shattering, and fracture lines) described in literature were observed in the post-mortem imaging of this case.

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Patients with orthostatic hypotension may experience neck pain radiating to the occipital region of the skull and the shoulders while standing (so-called coat-hanger ache). This study assessed muscle membrane potential in the trapezius muscle of patients with orthostatic hypotension and healthy subjects during head-up tilt (HUT), by measuring velocity recovery cycles (VRCs) of muscle action potentials as an indicator of muscle membrane potential.

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Craniosynostosis consists of a premature fusion of the sutures in an infant skull that restricts skull and brain growth. During the last decades, there has been a rapid increase of fundamentally diverse surgical treatment methods. At present, the surgical outcome has been assessed using global variables such as cephalic index, head circumference, and intracranial volume. However, these variables have failed in describing the local deformations and morphological changes that may have a role in the neurologic disorders observed in the patients. This report describes a rigid image registration-based method to evaluate outcomes of craniosynostosis surgical treatments, local quantification of head growth, and indirect intracranial volume change measurements. The developed semiautomatic analysis method was applied to computed tomography data sets of a 5-month-old boy with sagittal craniosynostosis who underwent expansion of the posterior skull with cranioplasty. Quantification of the local changes between pre- and postoperative images was quantified by mapping the minimum distance of individual points from the preoperative to the postoperative surface meshes, and indirect intracranial volume changes were estimated. The proposed methodology can provide the surgeon a tool for the quantitative evaluation of surgical procedures and detection of abnormalities of the infant skull and its development.