A complete situs inversus viscerum with hepatic, intestinal and renalvascular anomalies: one case report and review of the literatur

Situs inversus viscerum (SIV) is a rare congenital anomaly, which is still an intriguing phenomenon to anatomists and physicians alike. A complete SIV is characterized by a left-right transposition and mirror image of all thoraco-abdominal organs and their vasculature. The present report is based on one case with complete SIV, which was observed during the routine educational dissections of cadavers in the authors' Anatomy Department. A transposition of all truncal organs and their vasculature, and several variations of arteries and veins were present. The right branch of the proper hepatic artery was replaced by an artery that emanated from the superior mesenteric artery. The latter also released the inferior mesenteric artery. Additionally, a left accessory renal artery ran anterior to the inferior caval vein and posterior to the ureter to enter the hilum of the left kidney. There was also a variation in the anterior-posterior arrangement of the hilar structures of the left kidney. Additionally, a globally enlarged heart with coronary artery by-passes, a replaced aortic valve and an aortic arch aneurysm was observed. This case report is unique, as it presents a previously unreported co-incidence of SIV and hepatic, intestinal and renal vascular anomalies. It is important for the surgeon to be aware of such variations while planning an abdominal surgery in patients with SIV

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Altered laryngeal morphology in Period1 deficient mice.

BACKGROUND: Ultrasonic vocalizations (USV) of mice are produced in and emitted by the larynx. However, which anatomical elements of the mouse larynx are involved and to which aspects of USV they contribute is not clear. Frequency and amplitude parameters of mice, deficient in the clock gene Period1 (mPer1-/- mice) are distinguishably different compared to C3H wildtype (WT) controls. Because structural differences in the larynx may be a reason for the different USV observed, we analyzed laryngeal anatomy of mPer1-/- mice and WT control animals using micro-computed-tomography and stereology. RESULTS: In mPer1-/- mice, we found laryngeal cartilages to be normally arranged, and the thyroid, arytenoid and epiglottal cartilages were similar in diameter and volume measurements, compared to WT mice. However, in the cricoid cartilage, a significant difference in the dorso-ventral diameter and volume was evident. CONCLUSION: Our findings imply that laryngeal morphology is affected by inactivation of the clock gene Period1 in mice, which may contribute to their abnormal USV.

Illustrated versus non-illustrated anatomical test items in anatomy course tests and German Medical Licensing examinations (M1).

Illustrated Multiple-choice questions (iMCQs) form an integral part of written tests in anatomy. In iMCQs, the written question refers to various types of figures, e. g. X-ray images, micrographs of histological sections, or drawings of anatomical structures. Since the inclusion of images in MCQs might affect item performance we compared characteristics of anatomical items tested with iMCQs and non-iMCQs in seven tests of anatomy courses and in two written parts of the first section of the German Medical Licensing Examination (M1). In summary, we compared 25 iMCQs and 163 non-iMCQs from anatomy courses, and 27 iMCQs and 130 non-iMCQs from the written part of the M1 using a nonparametric test for unpaired samples. As a result, there were no significant differences in difficulty and discrimination levels between iMCQs and non-iMCQs, the same applied to an analysis stratified for MCQ formats. We conclude that the illustrated item format by itself does not seem to affect item difficulty. The present results are consistent with previous retrospective studies which showed no significant differences of test or item characteristics between iMCQs and non-iMCQs.

Impact of a Met(11)Thr single nucleotide polymorphism of surfactant protein D on allergic airway inflammation in a murine asthma model.

The surfactant-associated proteins SP-A and D are pattern recognition molecules with collectin structure. A single nucleotide polymorphism (SNP) exchanging a methionine (Met) for a threonine (Thr) in the amino-terminal SP-D domain influences the oligomeric structure and function of the protein. In this study, we investigated the susceptibility of mice transgenic for the human SP-D Met(11)Thr SNP to allergic airway inflammation and consequences for microRNA (miRNA, miR) expression. Mice expressing either human Met or Thr SP-D were sensitized and challenged with ovalbumin (OVA) in an acute model of allergic asthma. The influence of the SP-D polymorphism on the allergic airway inflammation was evaluated by lung function measurement, pulmonary inflammation parameters, morphological analysis and miRNA expression. Airway hyperresponsiveness, allergic inflammation, and mucus metaplasia were not significantly different between mice expressing one or the other allelic variant of SP-D. OVA sensitization and challenge led to significant airway hyperresponsiveness in wildtype mice and significantly lower eosinophil numbers and interleukin 5 levels in Thr SP-D mice. OVA challenge induced an upregulation of miR-21 and 155 in Thr SP-D mice and a downregulation of miR-21 in Met SP-D mice. Our results show that murine expression of human polymorphic SP-D variants does not significantly influence the severity of allergic airway inflammation. MiR-21 and 155 are differentially regulated in transgenic mice in response to allergic inflammation. Further studies are required to elucidate the impact of this SNP on inflammatory conditions of the lung.

Of rodents and humans: a light microscopic and ultrastructural study on cardiomyocytes in pulmonary veins.

Cardiomyocytes in pulmonary veins (PVs) have been reported in rodents and humans. In humans they were related to atrial arrhythmias, including atrial fibrillation (AF). To investigate histological similarities and differences in PV cardiomyocyte localization and distribution, we performed comparative light and electron microscopic studies on humans, rats and mice, and generated a transgenic mouse strain. Results on mice (C57BL/6 and BALBc) and rats (Wistar) revealed that cardiomyocytes regularly extend from the hilus along venous vessels into the lung tissue surrounding individual intrapulmonary veins of varying diameters (70-250 microm). The cardiomyocytes showed the ultrastructure of a normal working myocardium with intact intercalated discs and tightly packed contractile filaments. In both lung and hilus cardiomyocytes were localized either close to the basal lamina of the endothelium or separated from it by smooth muscle cells and/or collagen fibres. In humans (autopsies, n=20) extrapericardiac cardiomyocytes were only found in 23 out of 78 veins and showed an incomplete sleeve at the lung hilus. In addition, cardiomyocytes occurred significantly more often in right than in left veins, however, never in intrapulmonary veins. We discuss the hypothesis that the variance in distribution of PV cardiomyocytes in humans and rodents might reflect the difference in pathogenesis and development of AF.