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Circulatory System (circulatory + system)
Terms modified by Circulatory System Selected AbstractsThe origin of the endothelial cells: an evo-devo approach for the invertebrate/vertebrate transition of the circulatory systemEVOLUTION AND DEVELOPMENT, Issue 4 2005R. Muñoz-Chápuli Summary Circulatory systems of vertebrate and invertebrate metazoans are very different. Large vessels of invertebrates are constituted of spaces and lacunae located between the basement membranes of endodermal and mesodermal epithelia, and they lack an endothelial lining. Myoepithelial differentation of the coelomic cells covering hemal spaces is a frequent event, and myoepithelial cells often form microvessels in some large invertebrates. There is no phylogenetic theory about the origin of the endothelial cells in vertebrates. We herein propose that endothelial cells originated from a type of specialized blood cells, called amoebocytes, that adhere to the vascular basement membrane. The transition between amoebocytes and endothelium involved the acquisition of an epithelial phenotype. We suggest that immunological cooperation was the earliest function of these protoendothelial cells. Furthermore, their ability to transiently recover the migratory, invasive phenotype of amoebocytes (i.e., the angiogenic phenotype) allowed for vascular growth from the original visceral areas to the well-developed somatic areas of vertebrates (especially the tail, head, and neural tube). We also hypothesize that pericytes and smooth muscle cells derived from myoepithelial cells detached from the coelomic lining. As the origin of blood cells in invertebrates is probably coelomic, our hypothesis relates the origin of all the elements of the circulatory system with the coelomic wall. We have collected from the literature a number of comparative and developmental data supporting our hypothesis, for example the localization of the vascular endothelial growth factor receptor-2 ortholog in hemocytes of Drosophila or the fact that circulating progenitors can differentiate into endothelial cells even in adult vertebrates. [source] The effects of acute and chronic exercise on the vasculatureACTA PHYSIOLOGICA, Issue 4 2010J. J. Whyte Abstract Regular physical activity (endurance training, ET) has a strong positive link with cardiovascular health. The aim of this review is to draw together the current knowledge on gene expression in different cell types comprising the vessels of the circulatory system, with special emphasis on the endothelium, and how these gene products interact to influence vascular health. The effect beneficial effects of ET on the endothelium are believed to result from increased vascular shear stress during ET bouts. A number of mechanosensory mechanisms have been elucidated that may contribute to the effects of ET on vascular function, but there are questions regarding interactions among molecular pathways. For instance, increases in flow brought on by ET can reduce circulating levels of viscosity and haemostatic and inflammatory variables that may interact with increased shear stress, releasing vasoactive substances such as nitric oxide and prostacyclin, decreasing permeability to plasma lipoproteins as well as the adhesion of leucocytes. At this time the optimal rate-of-flow and rate-of-change in flow for determining whether anti-atherogenic or pro-atherogenic processes proceed remain unknown. In addition, the impact of haemodynamic variables differs with vessel size and tissue type in which arteries are located. While the hurdles to understanding the mechanism responsible for ET-induced alterations in vascular cell gene expression are significant, they in no way undermine the established benefits of regular physical activity to the cardiovascular system and to general overall health. This review summarizes current understanding of control of vascular cell gene expression by exercise and how these processes lead to improved cardiovascular health. [source] Vascular anatomy of the developing medaka, Oryzias latipes: A complementary fish model for cardiovascular research on vertebratesDEVELOPMENTAL DYNAMICS, Issue 3 2006Misato Fujita Abstract The zebrafish has become a very useful vertebrate model for cardiovascular research, but detailed morphogenetic studies have revealed that it differs from mammals in certain aspects of the primary circulatory system, in particular, the early vitelline circulation. We searched for another teleost species that might serve as a complementary model for the formation of these early primary vessels. Here (and online at http://www.shigen.nig.ac.jp/medaka/atlas/), we present a detailed characterization of the vascular anatomy of the developing medaka embryo from the stage 24 (1 day 20 hr) through stage 30 (3 days 10 hr). Three-dimensional images using confocal microangiography show that the medaka, Oryzias latipes, follows the common embryonic circulatory pattern consisting of ventral aorta, aortic arches, dorsal aorta, transverse vessels, vitelline capillary plexus, and marginal veins. The medaka, thus, may serve as a valuable model system for genetic analysis of the primary vasculature of vertebrates. Developmental Dynamics 235:734,746, 2006. © 2006 Wiley-Liss, Inc. [source] The circulatory system in Chilopoda: functional morphology and phylogenetic aspectsACTA ZOOLOGICA, Issue 3 2002Christian 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] Vascular regeneration and angiogenic-like sprouting mechanism in a compound ascidian is similar to vertebratesEVOLUTION AND DEVELOPMENT, Issue 5 2008Fabio Gasparini SUMMARY Tunicates are useful models for comparing differing developmental processes such as embryogenesis, asexual reproduction, and regeneration, because they are the closest relatives to vertebrates and are the only chordates to reproduce both sexually and asexually. Among them, the ascidian Botryllus schlosseri displays high regenerative potential of the colonial circulatory system (CCS). The CCS runs in the common tunic, forming an anastomized network of vessels defined by simple epithelia and connected to the open circulatory system of the zooids. During asexual propagation, new vessels form by means of a tubular-sprouting mechanism, resembling that occurring in other metazoans, particularly during vertebrate angiogenesis. We studied the regeneration of experimentally ablated CCS by analyzing the general dynamics of reorganization of vessels and tunic, their ultrastructure, cell proliferation, and the immunohistology of regenerating structures using antibodies against vertebrate angiogenic factors-vascular endothelial growth factor (VEGF), fibroblast growth factor-2 (FGF-2), epidermal growth factor (EGF), and receptors: VEGFR-1, VEGFR-2, and EGFR. Results show that the regenerative process of CCS occurs by a sprouting mechanism, with participation of angiogenic factors. They also show correspondence between the CCS sprouting of B. schlosseri and angiogenic sprouting in vertebrates, during both normal development and regeneration, and support the idea that this morphogenetic mechanism was co-opted during the evolution of various developmental processes in different taxa. [source] The origin of the endothelial cells: an evo-devo approach for the invertebrate/vertebrate transition of the circulatory systemEVOLUTION AND DEVELOPMENT, Issue 4 2005R. Muñoz-Chápuli Summary Circulatory systems of vertebrate and invertebrate metazoans are very different. Large vessels of invertebrates are constituted of spaces and lacunae located between the basement membranes of endodermal and mesodermal epithelia, and they lack an endothelial lining. Myoepithelial differentation of the coelomic cells covering hemal spaces is a frequent event, and myoepithelial cells often form microvessels in some large invertebrates. There is no phylogenetic theory about the origin of the endothelial cells in vertebrates. We herein propose that endothelial cells originated from a type of specialized blood cells, called amoebocytes, that adhere to the vascular basement membrane. The transition between amoebocytes and endothelium involved the acquisition of an epithelial phenotype. We suggest that immunological cooperation was the earliest function of these protoendothelial cells. Furthermore, their ability to transiently recover the migratory, invasive phenotype of amoebocytes (i.e., the angiogenic phenotype) allowed for vascular growth from the original visceral areas to the well-developed somatic areas of vertebrates (especially the tail, head, and neural tube). We also hypothesize that pericytes and smooth muscle cells derived from myoepithelial cells detached from the coelomic lining. As the origin of blood cells in invertebrates is probably coelomic, our hypothesis relates the origin of all the elements of the circulatory system with the coelomic wall. We have collected from the literature a number of comparative and developmental data supporting our hypothesis, for example the localization of the vascular endothelial growth factor receptor-2 ortholog in hemocytes of Drosophila or the fact that circulating progenitors can differentiate into endothelial cells even in adult vertebrates. [source] Cocaine- and amphetamine-regulated transcript (CART) peptide as an in vivo regulator of cardiac function in Rana ridibunda frogEXPERIMENTAL PHYSIOLOGY, Issue 6 2007Iliyana V. Ivanova The aim of this study was to investigate the effect of CART peptide on cardiac performance and on the physiological signalling pathways involved using Rana ridibunda frog heart preparations in vivo. The CART peptide, when injected into the venous sinus, significantly and reproducibly increased the force of frog heart contractions by up to 33.0 ± 6.4% during the first 15 min after its application but did not influence the chronotropic activity of the frog heart. The positive inotropic effect was entirely blocked by prazosin, pertussis toxin, Rp -adenosine 3,,5,-cyclic monophosphorothioate, autosauvagine 30 or metyrapone, as well as by extirpation of the pituitary gland, functional elimination of the inter-renal glands and long-lasting starvation, and was not observed on isolated heart preparations. Propranolol and double pithing were without significant effect on this phenomenon. It was concluded that: (i) CART peptide, administered to frogs in vivo, increases the force of heart contractions; (ii) this effect of the peptide is exerted via activation of the hypothalamic,pituitary,inter-renal gland axis through a corticoliberin-sensitive mechanism; (iii) CART augments the pumping function of the heart via a corticosteroid-dependent potentiation of myocardial ,1 -adrenoreceptors signalling; and (iv) prolonged food deprivation abolishes the positive inotropic effect of CART, suggesting the participation of endogenous CART in the physiological adaptation of the circulatory system to limitations of energy consumption. [source] Collection of peripheral progenitor cells in paediatric patients with a new programme for the collection of mononuclear cellsJOURNAL OF CLINICAL APHERESIS, Issue 3 2003R. Moog Abstract When harvesting peripheral progenitor cells (PPC) in children, the special situation of their circulatory system has to be taken into account. Therefore, extracorporeal blood volume and product volume should be small to avoid side effects. Nine children (age 2,14 years, weight 12.8,58.5 kg) with malignancies underwent 10 PPC collections with the MNC programme of the Amicus blood cell separator. The disposable kit was primed with red blood cells (RBCs) or human albumin to avoid circulatory side effects. The children were monitored for blood pressure and heart rate during the whole apheresis procedure. A median blood volume of 4,577 ml (range 3,536,8,596 ml) was processed in a separation time of 270 min (range 176,331 min). The median product weight was 81 g (range 53,107 g) and the yield of CD 34 antigen expressing cells was 12.5 × 106/kg body weight (range 1.8,26 × 106/kg body weight). Only one child had to undergo a second apheresis to collect the desired transplantation dose. The median platelet contamination of the product was 0.32 × 1011 (0.13,0.85 × 1011). No circulatory side effects were observed. Blood flow alarms occurred in seven of ten aphereses and one collection had to be terminated due to insufficient flow. PPC can be efficiently collected in children with the MNC programme without circulatory side effects. The platelet contamination of the product was low due to the elutriation principle of the collection process, thereby avoiding thrombocytopenic bleeding episodes in the patients. J. Clin. Apheresis, 18:111,114, 2003. © 2003 Wiley-Liss, Inc. [source] Forensic Considerations in Cases of Neurofibromatosis,An OverviewJOURNAL OF FORENSIC SCIENCES, Issue 5 2007Roger W. Byard M.B.B.S. Abstract:, Neurofibromatosis types 1 and 2 are inherited neurocutaneous disorders characterized by a variety of manifestations that involve the circulatory system, the central and peripheral nervous systems, the skin, and the skeleton. Significant reduction in lifespan occurs in both conditions often related to complications of malignancy and hypertension. Individuals with these conditions may also be the subject of medicolegal autopsy investigation if sudden death occurs. Unexpected lethal events may be associated with intracranial neoplasia and hemorrhage or brainstem compression. Vasculopathy with fibrointimal proliferation may result in critical reduction in blood flow within the coronary or cerebral circulations, and aneurysmal dilatation may be associated with rupture and life-threatening hemorrhage. An autopsy approach to potential cases should include review of the history/hospital record, liaison with a clinical geneticist (to include family follow-up), a full external examination with careful documentation of skin lesions and nodules, measurement of the head circumference in children, photography, possible radiologic examination, a standard internal autopsy examination, documentation of the effects of previous surgery and/or chemo/radiotherapy, examination for specific tumors, specific examination and sampling of vasculature (renal, cerebral, and cardiac), formal neuropathologic examination of brain and spinal cord, possible examination of the eyeballs, examination of the gastrointestinal tract, histology to include tumors, vessels, gut, and bone marrow, toxicological testing for anticonvulsants, and sampling of blood and tissue for possible cytogenetic/molecular evaluation if required. [source] Comparative morphology of the hemolymph vascular system in scorpions,A survey using corrosion casting, MicroCT, and 3D-reconstructionJOURNAL OF MORPHOLOGY, Issue 5 2007Christian S. Wirkner Abstract Although scorpions are one of the better known groups of Arthropoda, detailed knowledge of their anatomy remains superficial. This contribution presents the first comprehensive investigation of the gross morphology of the scorpion vascular system, based on a survey of species representing all major lineages of the order, using classical and modern non-destructive techniques in combination with three-dimensional reconstruction. The investigation reveals that the hemolymph vascular system (HVS) of Scorpiones comprises a central pumping heart which extends the entire length of the mesosoma and is enclosed in a pericardium. Several arteries branch off the heart to supply different organs and body regions. Two different anterior aorta major branching patterns are identified among the species investigated. Arteries that branch off the anterior aorta system supply the appendages (chelicerae, pedipalps, and walking legs) and the central nerve mass with a complex arterial network. This study of the HVS of scorpions provides further evidence that the vascular systems of euarthropods can be highly complex. Use of the term "open circulatory system" within arthropods is re-emphasized, as it refers to the general organization of the body cavity (i.e. mixocoely) rather than to the complexity of the circulatory system. J. Morphol., 2007. © 2007 Wiley-Liss, Inc. [source] Use of the molecular adsorbents recirculating system as a treatment for acute decompensated wilson diseaseLIVER TRANSPLANTATION, Issue 10 2008Alexander Chiu Acute decompensated Wilson disease presenting as fulminant liver failure is a life-threatening condition for which liver transplantation is the ultimate treatment. It is listed as a status 1 indication according to the United Network for Organ Sharing classification. A massive amount of copper released during the attack induces hemolytic anemia and acute renal failure. Conventional chelating therapy attempting to remove copper from the patient is not satisfactory because there is inadequate time for these drugs to take action and patients are usually oliguric. The Molecular Adsorbents Recirculating System (MARS) is a form of modified dialysis that removes putative albumin-bound toxins associated with liver failure. It is believed that extracorporeal albumin dialysate absorbs the circulating copper molecules that are trapped in the patient's circulation. We report 2 patients with acute decompensated Wilson disease treated with MARS. In the first case, the patient was started on MARS once conventional treatment failed. A significant amount of copper was removed from her circulatory system, and her condition stabilized afterwards. The treatment gained her extra time, and she was eventually bridged to liver transplantation. In the second case, the patient was started on MARS treatment early in the course of his illness, and his condition soon stabilized after the treatment. He was able to return to his home country for liver transplantation. In both cases, MARS was used as a means of preventing deterioration rather than salvaging devastation. In conclusion, MARS may confer benefits to patients with acute decompensated Wilson disease if it is started early in the course of illness. Liver Transpl 14:1512,1516, 2008. © 2008 AASLD. [source] The Circulatory System: Blood Procurement, AIDS, and the Social Body in ChinaMEDICAL ANTHROPOLOGY QUARTERLY, Issue 2 2006Kathleen Erwin The market for blood thrived in China for more than a decade, preying on rural villagers desperate for cash. Profit motives and unhygienic collection created an AIDS epidemic, where now up to 80 percent of adults in some villages are HIV infected. Today, illegal blood banks continue to operate in some areas. Moreover, better screening and blood testing do little to address the underlying cultural reluctance to give blood. This article examines what is at stake for blood donors in the circulation of blood through both the physical and the social bodies in China today. I argue that public health and social policy solutions require consideration of the symbolic meanings of blood and the body, kin relations, and gift exchange. China's HIV-contaminated blood procurement crisis demands a critical reexamination of the hidden processes embedded in a "circulatory system" that has inseparably bound the "gift of life" and a "commodity of death." [source] Coupling 3D and 1D fluid-structure interaction models for blood flow simulationsPROCEEDINGS IN APPLIED MATHEMATICS & MECHANICS, Issue 1 2006L. Formaggia Three-dimensional (3D) simulations of blood flow in medium to large vessels are now a common practice. These models consist of the 3D Navier-Stokes equations for incompressible Newtonian fluids coupled with a model for the vessel wall structure. However, it is still computationally unaffordable to simulate very large sections, let alone the whole, of the human circulatory system with fully 3D fluid-structure interaction models. Thus truncated 3D regions have to be considered. Reduced models, one-dimensional (1D) or zero-dimensional (0D), can be used to approximate the remaining parts of the cardiovascular system at a low computational cost. These models have a lower level of accuracy, since they describe the evolution of averaged quantities, nevertheless they provide useful information which can be fed to the more complex model. More precisely, the 1D models describe the wave propagation nature of blood flow and coupled with the 3D models can act also as absorbing boundary conditions. We consider in this work the coupling of a 3D fluid-structure interaction model with a 1D hyperbolic model. We study the stability of the coupling and present some numerical results. (© 2006 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Body fluid proteomics: Prospects for biomarker discoveryPROTEOMICS - CLINICAL APPLICATIONS, Issue 9 2007Sung-Min Ahn Abstract Many diseases are caused by perturbations of cellular signaling pathways and related pathway networks as a result of genetic aberrations. These perturbations are manifested by altered cellular protein profiles in the fluids bathing tissue/organs (i.e., the tissue interstitial fluid, TIF). A major challenge of clinical chemistry is to quantitatively map these perturbed protein profiles , the so-called "signatures of disease" , using modern proteomic technologies. This information can be utilized to design protein biomarkers for the early detection of disease, monitoring disease progression and efficacy of drug action. Here, we discuss the use of body fluids in the context of prospective biomarker discovery, and the marked 1000,1500-fold dilution of body fluid proteins, during their passage from TIF to the circulatory system. Further, we discuss proteomics strategies aimed at depleting major serum proteins, especially albumin, in order to focus on low-abundance protein/peptides in plasma. A major limitation of depletion strategies is the removal of low-molecular weight protein/peptides which specifically bind major plasma proteins. We present a prototype model, using albumin, for understanding the multifaceted nature of biomarker research, highlighting the involvement of albumin in Alzheimer's disease. This model underscores the need for a system-level understanding for biomarker research and personalized medicine. [source] ORIGINAL ARTICLE: Preterm Labor: CD55 in Maternal Blood LeukocytesAMERICAN JOURNAL OF REPRODUCTIVE IMMUNOLOGY, Issue 5 2009Stella Nowicki Problem, Intrauterine inflammation is a frequent and significant factor associated with the pathogenesis of preterm labor/birth (PTL/PTB). However, it remains unclear whether the intrauterine inflammatory responses activate the maternal peripheral circulation. We explored the association between PTL/PTB and the ,activation' of the peripheral circulatory system by determining whether CD55 mRNA expression within peripheral WBCs differed between PTL and control patients not in labor. Method of Study, RNA was purified from white blood cells collected from pregnant women with preterm labor (n = 45), and from pregnant (n = 30) control women. CD55 gene expression was evaluated by quantitative PCR. Results, The mean CD55 mRNA level within the PTL group (0.77 ± 0.03) was 1.48-fold higher than that observed (0.52 ± 0.02) within the control group (P < 0.0001); 71% of PTL patients and only 6.7% of control subjects expressed elevated CD55 mRNA. The receiver operating characteristics (with 95% CI) of CD55 as a marker for PTL were as follows: Sensitivity, 69% (53,82%); Specificity, 93% (78,99%); Positive Predictive Value, 94% (80,99%); and Negative Predictive Value, 67% (51,80%). In the patient population that delivered prematurely (before 37 weeks), 81% expressed elevated CD55 mRNA levels with a mean of 0.78 ± 0.03 and 95% CI of 0.71,0.84. The receiver operating characteristics were as follows: Sensitivity, 73% (54,88%); Specificity, 86% (71,95%); Positive Predictive Value, 81.5% (62,94%); and Negative Predictive Value, 80% (64,91%). Conclusion, Here we report for the first time that CD55 mRNA expression was elevated in the peripheral WBCs of subjects with preterm labor compared with control gestationally-matched pregnant woman and that elevated leukocyte CD55 may be a useful predictor of subsequent PTB. [source] A New Pulsatile Volumetric Device With Biomorphic Valves for the In Vitro Study of the Cardiovascular SystemARTIFICIAL ORGANS, Issue 12 2009Ettore Lanzarone Abstract A pulsatile mock loop system was designed and tested. This prototype represents a versatile, adjustable, and controllable experimental apparatus for in vitro studies of devices meant to interface with the human circulatory system. The pumping system consisted of a ventricular chamber featuring two biomorphic silicone valves as the inlet and outlet valves. The chamber volume is forced by a piston pump moved by a computer-controlled, low-inertia motor. Fluid dynamic tests with the device were performed to simulate physiological conditions in terms of cardiac output (mean flow of 5 and 6 L/min, with beat rates from 60 to 80 bpm), of rheological properties of the processed fluid, and of systemic circulation impedance. The pulsating actuator performed a good replication of the physiological ventricular behavior and was able to guarantee easy control of the waveform parameters. Experimental pressure and flow tracings reliably simulated the physiological profiles, and no hemolytic subatmospheric pressures were revealed. The performance of the prototype valves was also studied in terms of dynamic and static backflow, effective orifice area, and pressure loss, resulting in their applicability for this device. Mechanical reliability was also tested over 8 h. The device proved to be a reliable lab apparatus for in vitro tests; the pumping system also represents a first step toward a possible future application of pulsating perfusion in the clinic arena, such as in short-term cardiac assist and pulsatile cardiopulmonary bypass. [source] Health status differentials across rural and remote AustraliaAUSTRALIAN JOURNAL OF RURAL HEALTH, Issue 1 2009Andrew Phillips Abstract This paper describes mortality and disease patterns across five broad remoteness categories of Australia, with reference to the context in which those outcomes develop and are treated. Health and its outcomes become worse as remoteness increases. Some of this phenomenon reflects proportionally greater numbers of Aboriginal and Torres Strait Islander people in remote areas coupled with their poorer overall health outcomes; however, mortality for non-indigenous people is clearly higher outside compared with inside major cities. Migration of people seeking services likely reduces the size of interregional health disparity. Poorer health outcomes stem from worse risk factor profiles and average lower levels of income and of education, poorer physical and financial access to services, higher occupational and environmental risk, as well as factors unique to Aboriginal and Torres Strait Islander health. Little is known about the health benefits of living outside major cities. Diseases of the circulatory system and injuries account, respectively, for 40% and 18% of the excess mortality outside major cities. Death rates are declining over time in all (particularly remote) areas, but rates of death due to certain lung diseases in rural women are not, and rates of suicide have increased in remote areas. Ostensibly, prevalence of mental ill-health appears roughly similar in all remoteness areas. Dental health is poorer and disability is more prevalent outside major cities, as are a range of infectious diseases. Although pertinent, the effects on rural health of climate change and resource degradation generally have not been addressed in this paper. [source] Chronic Hydrocephalus in AdultsBRAIN PATHOLOGY, Issue 3 2004Richard J Edwards Chronic hydrocephalus is a complex condition, the incidence of which increases with increasing age. It is characterised by the presence of ventricular enlargement in the absence of significant elevations of intracranial pressure. The clinical syndrome may develop either as a result of decompensation of a "compensated" congenital hydrocephalus, or it may arise de novo in adult life secondary to a known acquired disturbance of normal CSF dynamics. The latter may be due to late onset acqueductal stenosis or disruption of normal CSF absorptive pathways following subarachnoid hemorrhage or meningitis ("secondary" normal pressure hydrocephalus (NPH)). In some cases the cause of the hydrocephalus remains obscure ("idiopathic" NPH). In all forms of chronic hydrocephalus the clinical course of the disease is heavily influenced by changes in the brain associated with aging, in particular cerebrovascular disease. Recent research has challenged previously held tenets regarding the CSF circulatory system and this in turn has led to a radical rethinking of the pathophysiological basis of chronic hydrocephalus. [source] Drosophila melanogaster as a model for elucidating the pathogenicity of Francisella tularensisCELLULAR MICROBIOLOGY, Issue 6 2008Malin Vonkavaara Summary Drosophila melanogaster is a widely used model organism for research on innate immunity and serves as an experimental model for infectious diseases. The aetiological agent of the zoonotic disease tularaemia, Francisella tularensis, can be transmitted by ticks and mosquitoes and Drosophila might be a useful, genetically amenable model host to elucidate the interactions between the bacterium and its arthropod vectors. We found that the live vaccine strain of F. tularensis was phagocytosed by Drosophila and multiplied in fly haemocytes in vitro and in vivo. Bacteria injected into flies resided both inside haemocytes and extracellularly in the open circulatory system. A continuous activation of the humoral immune response, i.e. production of antimicrobial peptides under control of the imd/Relish signalling pathway, was observed and it may have contributed to the relative resistance to F. tularensis as flies defective in the imd/Relish pathway died rapidly. Importantly, bacterial strains deficient for genes of the F. tularensis intracellular growth locus or the macrophage growth locus were attenuated in D. melanogaster. Our results demonstrate that D. melanogaster is a suitable model for the analysis of interactions between F. tularensis and its arthropod hosts and that it can also be used to identify F. tularensis virulence factors relevant for mammalian hosts. [source] Evolutionary morphology of the circulatory system in Peracarida (Malacostraca; Crustacea)CLADISTICS, Issue 2 2010Christian S. Wirkner We demonstrate that by formulating guidelines for evolutionary morphology the transparency, reproducibility, and intersubject testability of evolutionary hypotheses based on morphological data can be enhanced. The five main steps in our concept of evolutionary morphology are (i) taxon sampling, (ii) structural analysis, (iii) character conceptualization, (iv) phylogenetic analysis, and (v) evolutionary interpretation. We illustrate this concept on the example of the morphology of the circulatory organs in peracarid Malacostraca. The analysis is based on recently published accounts in which detailed structural analyses were carried out, and on the older literature. Detailed conceptualizations of 22 characters of the circulatory system are given for 28 terminals. In a further step these characters are included in a recently revised matrix, resulting in 110 characters. The resulting parsimony analysis yielded a single most parsimonious tree with a length of 309 steps. The most significant results are that Peracarida is monophyletic, Amphipoda is the sister taxon to the Mancoida sensu stricto, the relict cave-dwelling taxa Thermosbaenacea, Spelaeogriphacea, and Mictocarididae form a monophylum and Tanaidacea is the sister group to a monophylum comprising Cumacea and Isopoda. The evolutionary analysis shows that the ground pattern features of the circulatory organs in Peracarida are a tubular heart extending through the whole thorax, a posterior aorta with lateral arteries, and a ventral vessel system. Important features within the Peracarida are the backward shift of the anterior border of the heart, the reduction of the ventral vessel system, and two patterns of cardiac arteries, one common to the amphipod and tanaidacean terminals, and one to the cumacean and isopod terminals. ,© The Willi Hennig Society 2009. [source] Rare variations of the left subclavian arteryCLINICAL ANATOMY, Issue 5 2005Faysal A. Saadeh Abstract The subclavian artery is a major constituent of the blood circulatory system. Its position in the root of the neck and its course through the interscalene triangle are significant. Its branches supply divers areas in the body from the brain to the thorax. This case report describes an unusual range of anatomical variations of the course of the left subclavian artery, the origin, and absence of some of its branches and the concomitant abnormal course of the phrenic nerve. Clinical syndromes related to certain variations are reviewed. Clin. Anat. 18:370,372, 2005. © 2005 Wiley-Liss, Inc. [source] Mortality among persons with a history of Kawasaki disease in Japan: Can paediatricians safely discontinue follow-up of children with a history of the disease but without cardiac sequelae?ACTA PAEDIATRICA, Issue 4 2005Yosikazu Nakamura Abstract Aim: To clarify the question of whether patients with Kawasaki disease suffer a higher mortality rate after the incidence of the disease in comparison with age-matched healthy individuals. Methods: Between July 1982 and December 1992, 52 collaborating hospitals collected data on all patients having a new, definite diagnosis of Kawasaki disease. Patients were followed up until 31 December 2001 or their death. The expected number of deaths was calculated from Japanese vital statistics data and compared with the observed number. Results: Of 6576 patients enrolled, 29 (20 males and 9 females) died. The standardized mortality ratio (SMR: the observed number of deaths divided by the expected number of deaths based on the vital statistics in Japan) was 1.15 (95% CI: 0.77,1.66). In spite of the high SMRs during the acute phase, the mortality rate was not high after the acute phase for the entire group of patients. Although the SMR after the acute phase was 0.75 for those without cardiac sequelae, six males (but none of the females) with cardiac sequelae died during this period; and the SMR for the male group with cardiac sequelae was 1.95 (95% CI: 0.71,4.25). The mortality from congenital anomalies of the circulatory system was elevated, but no increase in cancer deaths was observed. Conclusion: Although it was not statistically significant, the mortality rate among males with cardiac sequelae due to Kawasaki disease appeared to be higher than in the general population. On the other hand, the mortality rates for females with the sequelae and both males and females without sequelae were not elevated. [source] Selection of an Escherichia coli O157:H7 bacteriophage for persistence in the circulatory system of mice infected experimentallyCLINICAL MICROBIOLOGY AND INFECTION, Issue 3 2006R. Capparelli Abstract A bacteriophage lytic for Escherichia coli O157:H7 was isolated from bovine manure. Following in-vivo selection, the phage acquired the capacity to persist in the circulatory system of mice for at least 38 days. When mice were infected experimentally with E. coli O157:H7 (107 CFU/mouse), simultaneous injection of the mice with phage (108 PFU/mouse) cleared E. coli O157:H7 from the mice within 48 h. [source] Subacute toxicities and toxicokinetics of a new erectogenic, DA-8159, after single and 4-week repeated oral administration in dogsBIOPHARMACEUTICS AND DRUG DISPOSITION, Issue 3 2001Hyun J. Shim Abstract The subacute toxicities and toxicokinetics of a new erectogenic, DA-8159, were evaluated after single (at the 1st day) and 4-week (at the 28th day) oral administration of the drug, in doses of 0 (to serve as a control), 12.5, 50 and 200 mg/kg/day, to male and female dogs (n=3 for male and female dogs for each dose). DA-8159 had an effect on the immune-related organs (or tissues), circulatory systems, liver, adrenal glands, ovaries and pancreas. The toxic dose was 200 mg/kg and no observed adverse effect level was less than 50 mg/kg for male and female dogs. There were no significant gender differences in the pharmacokinetic parameters of DA-8159 for each dose after both single and 4-week oral administration. The pharmacokinetic parameters of DA-8159 were dose-independent after single oral administration; the time to reach a peak plasma concentration (Tmax) and the dose-normalized area under the plasma concentration,time curve from time zero to 24 h in plasma (AUC0,24 h) were not significantly different among three doses. However, accumulation of DA-8159 after 4-week oral administration was considerable at toxic dose, 200 mg/kg/day. For example, after 4-week administration, the dose-normalized AUC0,24 h value at 200 mg/kg/day (4.71 and 15.3 ,g h/ml) was significantly greater than that at 12.5 mg/kg/day. After 4-week oral administration, the dose-normalized Cmax and AUC0,24 h at 200 mg/kg/day were significantly higher and greater, respectively, than those after a single oral administration. Copyright © 2001 John Wiley & Sons, Ltd. [source] | ||||||||||||||||