Cardiomyopathy in the mouse model of Duchenne muscular dystrophy caused by disordered secretion of vascular endothelial growth factor.

BACKGROUND: Duchenne muscular dystrophy (DMD) is a genetic neuromuscular disorder that affects skeletal muscles and cardiac muscle tissue. In some cases, myocardial injury secondary to hypoxia can lead to dilative cardiomyopathy (DCM). A genetic defect in the dystrophin gene may increase the susceptibility of myocardium to hypoxia. Available data suggest that this may be caused by impaired secretion of NO, which is bound with secretion of VEGF-A. MATERIAL/METHODS: Male mice C57BI/10ScSn mdx (animal model of DMD) and healthy mice C57BI/10ScSn were exposed to hypobaric hypoxia in low-pressure chambers. Their hearts were harvested immediately after and 1, 3, 7, and 21 days after exposure to hypoxia. Normobaric mice were used as controls. The expression of VEGF-A in myocardium and cardiac vessel walls was evaluated using immunohistochemistry, Western blotting, and in situ hybridization. RESULTS: VEGF-A expression in myocardium and vessel walls of healthy mice peaked 24 hours after exposure to hypoxia. The expression of VEGF-A in vessel walls was similar in dystrophic and healthy mice; however, VEGF-A expression in the myocardium of dystrophic mice was impaired, peaking around day 7. In the heart, the total level of VEGF depends on VEGF expression in myocardium, not in vessel endothelium, and our research demonstrates that the expression of VEGF is dystrophin-dependent. CONCLUSIONS: Disordered secretion of VEGF-A in hypoxic myocardium caused the total level of this factor to be impaired in the heart. This factor, which in normal situations protect against hypoxia, promotes the gradual progression of cardiomyopathy.

[Endoparasite twin (fetus in fetu)]. / Plod pasozytujacy wewnetrznie (plód w plodzie-fetus in fetu).

Fetus in fetu is a very rare abnormality (estimated incidences: 1 in 500,000 deliveries), and is secondary to a pathological diamniotic monochorionic pregnancy. It consists of a malformed parasitic twin that is found within the body of its sibling. Hardly 70 cases have been reported in the literature since its first description about 1800. Its discovery is usually postnatal. We present two boys: two and half years and eleven days old newborn presented a mass in the retroperitoneum in the left upper abdominal quadrant. There were removed by surgery and contained two independent fetuses. Dissection and radiological study of the fetuses showed an axial skeleton and long bones. It corresponds to the generally recognized diagnostic criteria of fetus in fetu. The embryology, operative procedure, hypothesis and pathology of this condition are discussed and the literature briefly reviewed. The difference between teratomas and fetus in fetu is point.

Dimension of circumflex branch according to type of heart vascularisation in foetal life of human.

Typological differentiation of coronary arteries binds to various areas of vascularisation, which could suggest essential differences between vasculatory dimensions. There are not many papers analysing the influence of heart vascularisation on epicardial vessel dimensions during postnatal human life, furthermore, there are hardly any papers dealing with the prenatal period. The subject of examination was 188 human foetuses from 4th to 7th month of prenatal life. Foetuses were fixed for minimum 3 months in 9% formalin solution. They were taken from natural abortions and did not characterise any external malformations. There was a different number of foetuses in a variety of morphological age groups. Adachi classification was used to describe all types: type I--classical, with equal coronary arteries, type II--predominance of right coronary artery, type III--predominance of left coronary artery. Speed of circumflex branch growth in different types of vascularisation is various. Analysis of the differences among dimensions of artery in various types showed there are statistically crucial ones, especially between: types III and I or types III and II.

Correlation of heart external dimensions with body external dimensions of human foetuses.

In an evaluation of foetal hearts in II and III pregnancy semester, correlation with exterior foetal dimensions should be taken into consideration. It is interesting also if all exterior heart dimensions are correlated at the same level with overall body dimensions. The subject of examination was 204 foetuses of both sexes, including 106 males and 98 females, in 5th and 6th month of foetal life. Foetuses were fixed for minimum 3 months in 9% formalin solution. They were taken from natural abortions, without exterior features of developmental malformations. Examined material was evaluated in month groups of morphological age. The number of foetuses in different groups was various. Exterior heart dimensions were considered: height, width, heart depth, and also heart circumference in coronary sulcus (atrial-ventricular). Exterior dimensions of foetuses were: vertex-plantare, vertex-tubulare. All exterior dimensions of heart are closely and strongly correlated with both exterior dimensions of foetuses.