Augmented laminography, a correlative 3D imaging method for revealing the inner structure of compressed fossils

Non-destructive imaging techniques can be extremely useful tools for the investigation and the assessment of palaeontological objects, as mechanical preparation of rare and valuable fossils is precluded in most cases. However, palaeontologists are often faced with the problem of choosing a method among a wide range of available techniques. In this case study, we employ x-ray computed tomography (CT) and computed laminography (CL) to study the first fossil xiphosuran from the Muschelkalk (Middle Triassic) of the Netherlands. The fossil is embedded in micritic limestone, with the taxonomically important dorsal shield invisible, and only the outline of its ventral part traceable. We demonstrate the complementarity of CT and CL which offers an excellent option to visualize characteristic diagnostic features. We introduce augmented laminography to correlate complementary information of the two methods in Fourier space, allowing to combine their advantages and finally providing increased anatomical information about the fossil. This method of augmented laminography enabled us to identify the xiphosuran as a representative of the genus Limulitella

Inner ear morphology of diadectomorphs and seymouriamorphs (Tetrapoda) uncovered by high‐resolution x‐ray microcomputed tomography, and the origin of the amniote crown group

The origin of amniotes was a key event in vertebrate evolution, enabling tetrapods to break their ties with water and invade terrestrial environments. Two pivotal clades of early tetrapods, the diadectomorphs and the seymouriamorphs, have played an unsurpassed role in debates about the ancestry of amniotes for over a century, but their skeletal morphology has provided conflicting evidence for their affinities. Using high-resolution X-ray microcomputed tomography, we reveal the three-dimensional architecture of the well preserved endosseous labyrinth of the inner ear in representative species belonging to both groups. Data from the inner ear are coded in a new cladistic matrix of stem and primitive crown amniotes. Both maximum parsimony and Bayesian inference analyses retrieve seymouriamorphs as derived non-crown amniotes and diadectomorphs as sister group to synapsids. If confirmed, this sister group relationship invites re-examination of character polarity near the roots of the crown amniote radiation. Major changes in the endosseous labyrinth and adjacent braincase regions are mapped across the transition from non-amniote to amniote tetrapods, and include: a ventral shift of the cochlear recess relative to the vestibule and the semicircular canals; cochlear recess (primitively housed exclusively within the opisthotic) accommodated within both the prootic and the opisthotic; development of a distinct fossa subarcuata. The inner ear of seymouriamorphs foreshadows conditions of more derived groups, whereas that of diadectomorphs shows a mosaic of plesiomorphic and apomorphic traits, some of which are unambiguously amniote-like, including a distinct and pyramid-like cochlear recess

Dysphagie infolge einer isolierten oesophago-trachealen Fistel bei einem Neugeborenen

Hintergrund: Ursache einer Dysphagie im Säuglingsalter können angeborene Fisteln bei einer Fehlbildung von Speise- und Luftröhre sein (Häufigkeit 1 von 2.000 bis 4.000 Lebendgeburten). Isolierte Fisteln treten bei 1 zu 80.000 Geburten auf.Fallbericht: Anamnese: Nach Geburt zeigte das reife Neugeborene (41 SSW) beim Füttern auffällige Sättigungsabfälle, kurze Bradykardien, Hustenanfälle. Nach Übergang auf Sondierung war ein problemloser Kostaufbau möglich. Es bestand der Verdacht auf eine Larynxspalte oder oesophago-tracheale Fistel.Befunde: Röntgen-Thorax: keine pneumonischen Infiltrate, kein Pleuraerguss, Röntgen-Oesophagus-Breischluck: Oesophago-tracheale Fistel (H-Typ), Phoniatrischer Befund: Stimmlippen weiß, glatt, seitengleich beweglich, bei Phonation dichter Schluss, Arytenoidregion bds. deutliche Rötung, Epiglottis regelrecht, keine Residuen von Speichel, geringe Milchrückstände als einzelne Fäden,Schluckreflex auslösbar, Logopädischer Befund: bei Stimulation sofort kräftiges, physiologisches Saug-Schluckmuster, Phonation danach nicht brodlig, Mundmotorik unauffällig, Speichel wird offensichtlich abgeschluckt, Sonografie Schädel und Nieren, ableitende Harnwege o. B., Echokardiografie: kleines PFO, noch offener Ductus arteriosus, Tracheobronchoskopie und Oesophaguskopie: hohe oesophago-tracheale Fistel.Therapie: Es erfolgte der operative Verschluss der 3 mm großen, ca. 1 cm oberhalb der oberen Thoraxaperatur gelegenen oesophago-trachealen Fistel.Fazit: Bei Schluckstörungen im Neugeborenenalter sollte differentialdiagnostisch auch an eine Larynxspalte oder eine oesopgago-tracheale Fistel gedacht werden

Antibodies in the diagnosis of coeliac disease: A biopsy-controlled, international, multicentre study of 376 children with coeliac disease and 695 controls

Diagnosis of coeliac disease (CD) relies on a combination of clinical, genetic, serological and duodenal morphological findings. The ESPGHAN suggested that biopsy may not be necessary in all cases. New guidelines include omission of biopsy if the concentration of CD-specific antibodies exceeds 10 times the upper limit of normal (10 ULN) and other criteria are met. We analysed the 10 ULN criterion and investigated multiple antibody-assays. Serum was collected from 1071 children with duodenal biopsy (376 CD patients, 695 disease-controls). IgA-antibodies to tissue transglutaminase (IgA-aTTG), IgG-antibodies to deamidated gliadin peptides (IgG-aDGL) and IgA-endomysium antibodies (IgA-EMA) were measured centrally. We considered 3 outcomes for antibody test procedures utilizing IgA-aTTG and/or IgG-aDGL: positive (≥10 ULN, recommend gluten-free diet), negative (<1 ULN, no gluten-free diet) or unclear (perform biopsy). Positive (PPV) and negative (NPV) predictive values were based on clear test results. We required that they and their lower confidence bounds (LCB) be simultaneously very high (LCB >90% and PPV/NPV >95%). These stringent conditions were met for appropriate antibody-procedures over a prevalence range of 9–57%. By combining IgG-aDGL with IgA-aTTG, one could do without assaying total IgA. The PPV of IgG-aDGL was estimated to be extremely high, although more studies are necessary to narrow down the LCB. The proportion of patients requiring a biopsy was <11%. The procedures were either equivalent or even better in children <2 years compared to older children. All 310 of the IgA-aTTG positive children were also IgA-EMA positive. Antibody-assays could render biopsies unnecessary in most children, if experienced paediatric gastroenterologists evaluate the case. This suggestion only applies to the kits used here and should be verified for other available assays. Confirming IgA-aTTG positivity (≥10 ULN) by EMA-testing is unnecessary if performed on the same blood sample. Prospective studies are needed