Chemotaxis of Gametes: A Diffusion Approximation

Sexual attraction of male gametes toward females of many brownalgae species is induced by diffusible pheromones, which leadto a chemotactic modification of the loop-like 2-dimensionalswimming paths of the males. We propose a stochastic model andanalyse a suitable diffusion approximation in order to calculatequantities as the aggregation factor, the rotational flux component,and the mean mating time.     

THE MOLECULAR CONTROL OF ANGIOGENESIS

Angiogenesis is a key event in a broad range of pathological conditions including both diseases with an enhanced and insufficient angiogensis. Angiogenesis is often intiated with vasodilation accompanied by an increase in vascular permeability. After destabilization of the vessel wall and degradation of the surrounding extracellular matrix, extravasation of plasma proteins provides a provisional scaffold for the migration of endothelial cells. Endothileal cell proliferation and migration themselves are under tight control by a balance of angionenesis inducers and inhibitors. A large number of angiogenic factors work together in a highly coordinated manner to induce endothelial cell outgrowth and the formation of functional vessels. On the other hand, angiostatic factor may play a critical role in the pathogenesis of ischemic diseases and contribute to the temination of physiological angiogenesis. Angiogenesis ends with the recruitment of pericytes and smooth muscle cells, which stabilize the newly formed vessel. The rapid increase in the knowledge about the molecular mechanisms of angiogenesis has led to first treatment trials in diseases with both enhanced and reduced angiogeneis. Although initial results are promising, much more work has to be done to consdier anti-angiogenic or pro-angiogenic approaches as reliable therapeutic tools.     

Transesophageal Echocardiography in Candidates for Percutaneous Balloon Mitral Valvuloplasty

Prior to percutaneous balloon mitral valvuloplasty (PBMV), mitral valve morphology and the presence of left atrial thrombi are usually evaluated by transthoracic two-dimensional and Doppler echocardiography (TTE). This study analyzes the impact of transesophageal echocardiography (TEE) in addition to TTE on the selection of candidates considered for PBMV for mitral stenosis. Seventy-five patients with severe mitral stenosis who were considered as appropriate candidates for PBMV based on TTE findings were studied. In 19 (25%) patients, TEE revealed findings that were essential for PBMV but were missed by TTE: left atrial thrombi (n = 14; including 13 in left atrial appendage), right atrial thrombus (n = 1), incomplete cor triatriatum (n = 1) and mitral valve vegetation (n = 1). In two other patients, a left atrial thrombus had been suspected by TTE but could be excluded by TEE. TEE and TTE revealed similar scores of thickening, calcification, and mobility of the mitral valve. Compared to TTE, thickening of the subvalvular apparatus was graded lower using horizontal plane TEE due to shadowing by the mitral valve (echo score 1.8 ± 0.8 vs 1.4 ± 0.7; P < 0.05) whereas results from longitudinal plane TEE were similar to TTE findings. The data show that due to the high prevalence of left atrial thrombi, TEE should be performed in addition to TTE in all patients prior to PBMV.     

Waardenburg Syndrome Type I with Heterochromia Iridis and Circumscribed Hypopigmentation of the Skin

Abstract: We report a 3‐year‐old girl with autosomal dominant inherited Waardenburg syndrome type I showing circumscribed hypopigmentation of the skin, heterochromia iridis, sensorineural deafness, and dental aberrations. Clinical diagnosis was confirmed by the identification of an underlying missense mutation (C811T) in the PAX3 gene. Early diagnosis of Waardenburg syndrome among children with pigment anomalies enables a successful interdisciplinary medical care.     

Drosophila Rolling pebbles colocalises and putatively interacts with alpha-Actinin and the Sls isoform Zormin in the Z-discs of the sarcomere and with Dumbfounded/Kirre, alpha-Actinin and Zormin in the terminal Z-discs

The rolling pebbles gene of Drosophila encodes two proteins, one of which, Rols7, is essential for myoblast fusion. In addition, Rols 7 is expressed during myofibrillogenesis and in the mature muscles. Here it overlaps with alpha-Actinin (α-Actn) and the N-terminus of D-Titin/Kettin/Zormin in the Z-line of the sarcomeres. In the attachment sites of the somatic muscles, Rols7 and the immunoglobulin superfamily protein Dumbfounded/Kin of irreC (Duf/Kirre) colocalise. As Duf/Kirre is detectable only transiently, it may be involved in establishing the first contact of the outgrowing muscle fiber to the epidermal attachment site. We propose that Rols7 and Duf/Kirre link the terminal Z-disc to the cell membrane by direct interaction. This is supported by the fact that in yeast two hybrid assays the tetratricopeptide repeat E (TPR E) of Rols7 shows interaction with the intracellular domain of Duf/Kirre. The colocalisation of Rols7 with α-Actn and with D-Titin/Kettin/Zormin in the Z-dics is reflected in␣interactions with different domains of Rols7 in this assay. In summary, these data show that besides the role in myoblast fusion, Rols7 is a scaffold protein during myofibrillogenesis and in the Z-line of the sarcomere as well as in the terminal Z-disc linking the muscle to the epidermal attachment sites.     

CARDIAC INVOLVEMENT IN JUVENILE RHEUMATOID ARTHRITIS

ABSTRACT. Cardiac involvement was diagnosed in 15 of 320 cases of JRA (4.7%) and was most frequent in children with active systemic disease. Ten children had pericarditis, 2 had myocarditis, 2 had peri-myocarditis and 1 had aortic valvulitis. The highest risk of heart involvement was found during the first three years but it could occur at any time. Recurrent episodes were seen in 60% of cases. The prognosis in pericarditis seems to be good since no patient developed cardiac tamponade or constrictive pericarditis and cardiac function evaluated by echocardiography was normal in all patients at follow-up. In patients with myocarditis and peri-myocarditis, a dilated left ventricle was found in 2 of 4 patients and 1 patient who died, had severe cardiac changes at autopsy. The prognosis in myocarditis thus seems to be worse. In valvulitis the prognosis depends on which valve is involved. The benefit of early treatment with corticosteroids is discussed.     

Effect of Supplementation with Folinic Acid, Vitamin B6, and Vitamin B12 on Valproic Acid-Induced Teratogenesis in Mice

The effect of administration of folinic acid, vitamin B₆ + vitaminB₁₂, and their combination on valproic acid (VPA)-induced teratogenesiswas studied in NMRI mice. VPA (500 mg/kg, sc) was injected onDay 8 of gestation and the vitamins (two dose levels) were injectedip 1 hr before, immediately before, and 1 hr after VPA administration.Folinic acid significantly reduced VPA-induced resorptions (21–24%),and palate, rib, and sternebral malformations. Exencephaly andspina bifida occulta were also reduced (14 and 40%, respectively),but the difference was not statistically significant. On theother hand, vitamin B₆ + vitamin B₁₂ significantly reduced VPA-inducedexencephaly (23%), spina bifida occulta (80%), palate and ribmalformations, kidney abnormalities, and fetal weight retardation.A combination of the three vitamins was effective in reducingVPA-in duced exencephaly (23–30%), spina bifida occulta(60%), and palate and rib malformations. The protection againstVPA-induced malformations was not complete and was not alwaysdose related, and the reduction in exencephaly rate was onlysignificant in the absence of a reduction in resorption rate.Full-length cleft palate, sternebral malformations, and retardedsternebral and caudal ossification were, however, increasedby the high dose of combined vitamin administration. The presentstudy supports the view that VPA-induced teratogenesis may bemediated via an interaction with folate metabolism. Althoughfolinic acid and vitamin B₆ + vitamin B₁₂ can effectively reduceVPA malformations, the protection was not complete, which maysuggest the involvement of other factors. Furthermore, the doselevels should be carefully chosen since high doses of the combinedvitamins can actually increase the incidence of certain defects.     

Erfahrungen mit dem CACH-Medium zum Nachweis von Trichomonaden und Hefepilzen bei Frauen mit Scheidenentzündungen

Das 1960 von W. A. MÜLLER entwickelte CACH-Medium hat sich gut für den kulturellen Nachweis von Trichomonaden und Hefepilzen in Vaginal- und Urethrasekret von Frauen mit Scheidenentzündungen, die die Ambulanz der Frauenklinik aufsuchten, bewährt. Die Zubereitung des Anreicherungsmediums und die Untersuchungstechnik zur Ermittlung dieser Mikroben werden beschrieben. Die mitgeteilten Erfahrungen stützen sich auf die Ergebnisse, die bei der mykologischen und parasitologischen Untersuchung von 1526 Vaginal- bzw. Urethraabstrichen von 639 Frauen mit Scheidenentzündungen erzielt werden konnten.