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Peripheral Vessels (peripheral + vessel)

Distribution by Scientific Domains

Medical Sciences	66%

Selected Abstracts

The circulatory system in Chilopoda: functional morphology and phylogenetic aspects

ACTA ZOOLOGICA, Issue 3 2002
Christian S. Wirkner
Abstract The circulatory organs of nine representative species of all five chilopod orders were examined by light microscopy and by in vivo observations of haemolymph flow. In Scutigera coleoptrata, the heart ultrastructure was studied. The circulatory system in Craterostigmomorpha is described for the first time. Further focus is placed on the Geophilomorpha since previous descriptions in this group have been only superficial. In all investigated species, the circulatory system consists of two longitudinal central vessels which are connected in the first body segment by the maxilliped arch. The posterior part of these vessels is contractile and thus haemolymph is pumped anteriorly in the heart, while it is pumped posteriorly in the supraneural vessel. From these central vessels numerous peripheral vessels branch off. Differences among the chilopod orders lie mainly in the distribution of the peripheral vessels. The circulatory system in Scutigeromorpha shows some striking morphological adaptations with regard to the functional coupling of circulatory and respiratory tasks. The most peculiar structures are the aortic diverticles which act as accessory pumps in the head. Phylogenetic analysis of the circulatory organ traits within Chilopoda supports the Pleurostigmophora hypothesis. Synapomorphies supporting the Myriapoda hypothesis or the Tracheata concept were not found. [source]

Familial amyloidotic polyneuropathy (ATTR Val30Met) with widespread cerebral amyloid angiopathy and lethal cerebral hemorrhage

PATHOLOGY INTERNATIONAL, Issue 6 2001
Naomi Sakashita
We report an autopsy case of familial amyloidotic polyneuropathy (FAP) with cerebral hemorrhage. A 38-year-old woman with a typical FAP pedigree started developing severe diarrhea and sensori-motor polyneuropathy at the age of 28 years; autonomic nervous system, heart and renal dysfunction manifested themselves in the following years. Genetic analysis revealed a single amino acid substitution at codon 30 of transthyretin (ATTR Val30Met). Ten years after her initial symptoms, the patient died of a sudden convulsive attack and respiratory failure. Autopsy revealed lethal cerebral hemorrhages and uremic lungs. Histochemical and immunohistochemical analyses revealed TTR-derived amyloid protein in every tissue examined, particularly in glomeruli and peripheral vessels. Severe meningo-cerebrovascular amyloidosis was also detected. Because uremia causes oxidative damage to the vascular system and amyloid formation is closely associated with oxidative stress, it is possible that uremic endothelial damage facilitated an unusual cerebral amyloid deposition. In typical FAP (ATTR Val30Met), cerebral amyloid angiopathy does not usually have clinical manifestations. However, cerebral amyloid angiopathy should be considered to explain FAP symptoms when some risk factors such as uremic vascular damage are accompanying features. [source]

Catheter closure of moderate to large sized patent ductus arteriosus using the simultaneous double or triple coil technique

PEDIATRICS INTERNATIONAL, Issue 5 2001
Teiji Akagi
AbstractBackground: Although the clinical experience with transcatheter closure of the patent ductus arteriosus using the coils has grown rapidly, one important complication of this procedure using the conventional Gianturco coil was the migration of coils into peripheral vessels. This is especially for patients with a relatively larger size ductus and the risk for such complications could be increased. In this situation, the detachable coil may have some technical benefits to perform coil occlusion and reduce the incidence of complications. Methods: We describe the clinical efficacy of a simultaneous double or triple coil occlusion technique using the Cook detachable coil or bioptome delivered 0.052 inch Gianturco coil to close the ductus arteriosus. This was performed in patients whose ductus diameter was greater than 3.0 mm. Results: From February 1995 to December 2000, 118 patients with patent ductus arteriosus were treated by coil occlusion using Cook detachable coils, of whom 58 patients whose minimum diameter of ductus , 3.0 mm were reviewed. All patients had successful placement of coils. According to the evaluation by color flow mapping, a trivial shunt was observed in 17 patients (29%) within 24 h after the procedure. In 11 out of 17 patients, a residual shunt was not detected 1 month after the procedure. At 6 months after the procedure, the residual shunt was detected only in three patients. Conclusions: Although this study did not calculate the statistical significance between detachable and non-detachable coils in term of occlusion rate, our institutional experience suggests that the simultaneous double or triple coil technique using the detachable or 0.052 inch Gianturco coils can reduce the prevalence of coil migration or complications. [source]

Vascular and Biology 04

BRITISH JOURNAL OF SURGERY (NOW INCLUDES EUROPEAN JOURNAL OF SURGERY), Issue S1 2002
A.J. Hayes
Background: Angiopoietin-1 (Ang-1) functions physiologically to promote angiogenesis by inducing vascular branching and smooth muscle recruitment. However, we have previously reported to this Society that in an experimental breast cancer model, over-expression of Ang-1 led to tumour inhibition and that expression of Ang-1 in clinical breast cancer specimens was infrequent. We now report a morphological analysis of the tumour microvessels in this model in an attempt to ascertain a mechanism for tumour inhibition. Methods: Ang-1 over-expressing and vector-transfected xenograft tumours used in previous tumourigenicity assays were fixed routinely and sectioned. Endothelial cells and smooth muscle cells were immuno-stained with monoclonal antibodies to CD-31 and smooth muscle actin, visualized with confocal fluorescence microscopy and quantitated with image analysis. Tumours were also immuno-stained for markers of proliferation and apoptosis. Results: Ang-1 expressing tumours displayed striking differences in microvascular morphology at the leading edge of the tumour when compared with controls. Although the number of microvessels was not altered, the peripheral vessels in the Ang-1 tumours were much less ectatic than the dilated immature tumour vessels seen in controls. They were surrounded by a closely adherent continuous layer of smooth muscle cells, absent in controls. In these vessels the ratio of smooth muscle cells to endothelial cells was increased threefold (P < 0.01) and luminal diameter decreased twofold (P < 0.05) compared with controls. The rates of tumour cell proliferation and apoptosis were decreased twofold (P < 0.001) compared with controls. Conclusions: Ang-1 over-expression induced stabilization of microvessels at the tumour periphery, which resulted in a decreased rate of tumour growth. [source]

Coronary arteries in fetal life: physiology, malformations and the "heart-sparing effect"

ACTA PAEDIATRICA, Issue 2004
R ChaouiArticle first published online: 2 JAN 200
The present knowledge of coronary arteries in prenatal diagnosis is reviewed with a focus on three aspects: the physiology and visualization of coronary flow, malformations involving the coronary arteries, and the "heart-sparing effect". Visualization of coronary arteries in a healthy human fetus is possible in real-time and colour Doppler during the last 10wk of gestation when ultrasound conditions are excellent. Visualization at an earlier gestational age (up to 13 wk) is feasible mainly in association with malformations and impending hypoxia. The main coronary malformations that can be visualized in utero are the ventriculo-coronary communications in fetuses with pulmonary atresia. In the last few years, interest has been focused on the "heart-sparing effect", defined as the increased perfusion of the coronary arteries in fetuses with severe growth restriction and abnormal Doppler velocimetry in the peripheral vessels. Increased perfusion detectable with colour and pulsed Doppler is a late sign of fetal compromise in hypoxaemia. It confirms animal experiments that have demonstrated dilatory reserves of the fetal coronary arteries under chronic hypoxaemia. The outcome of 21 fetuses showing the "heart-sparing effect" before 32 wk gestation was poor: nine fetuses died in utero and two after birth, the median weight at birth was 630 g. In summary, our knowledge of the coronary arteries in the fetus is based on the diagnostic means used in prenatal diagnosis. New information in this field may also contribute to a better understanding of coronary heart disease later in life. [source]