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    Vasa Nervorum in rat major pelvic ganglion are innervated by nitrergic nerve fibers

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    INTRODUCTION The vasa nervorum comprises a network of small diameter blood vessels that provide blood supply to nerves and ganglia. The cell bodies of autonomic nerves innervating the urogenital organs are housed in the major pelvic ganglia (MPG) in rats. The vasa nervorum of rat MPG have not been characterized previously, and it is not known whether these blood vessels are innervated by neuronal nitric oxide synthase (nNOS) containing nitrergic nerves. AIM To characterize the blood vessels in and around the rat MPG and to assess their nitrergic innervation. MAIN OUTCOME MEASURES Characterization of small blood vessels in and around the rat MPG and expression of nNOS in nerve fibers around those blood vessels. METHODS MPG were obtained from healthy Sprague Dawley rats, fixed in paraformaldehyde, frozen and sectioned using a cryostat. The blood vessels and their nitrergic innervation were assessed with immunohistochemistry using antibodies against alpha-smooth muscle actin (smooth muscle marker), CD31 (endothelial marker), collagen IV (basal membrane marker) and nNOS. The immunofluorescence was imaged using a laser scanning confocal microscope. RESULTS The neuronal cell bodies were contained within a capsule in the MPG. Blood vessels were observed within the capsule of the MPG as well as outside the capsule. The blood vessels inside the capsule were CD31-positive capillaries with no smooth muscle staining. Outside the capsule capillaries, arterioles and venules were observed. The extra-capsular arterioles and venules, but not the capillaries were innervated by nNOS-positive nerve fibers. CONCLUSIONS This study, to our knowledge, is the first to demonstrate the blood vessel distribution pattern and their nitrergic innervation in the rat MPG. While similar studies in human pelvic plexus are warranted, these results suggest that the blood flow in the MPG may be regulated by nitrergic nerve fibers and reveal a reciprocal relationship between nerves and blood vessels. Beetson KA, Smith SF, Muneer A, Cameron NE, Cotter MA, and Cellek S. Vasa nervorum in rat major pelvic ganglion are innervated by nitrergic nerve fibers. J Sex Med **;**:**-**

    Establishing death in stranded Odontocetes (toothed whales) using other mammals : a pilot study : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Zoology at Massey University

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    The aim of this study was to investigate and evaluate a new method for determining death in stranded odontocetes (toothed whales). The new method was using the pulsations seen in the retinal blood vessels in the place of the heart rate. The retinal blood vessels can visualized, using an ophthalmoscope, in the fundus of the eye. Initially the procedure was to be testing using animals at a mass stranding, but there were no suitable strandings that took place during the time of the study. Therefore other mammal species were used to test the procedure. These mammals were cattle, sheep, and dogs, with additional observational testing carried out on seals, sea lions and dolphins. The mammals were chosen because of their availability and supply. The results showed that there was a strong relationship between the heart rate and the pulsations measured in the retinal blood vessels. This was expected as the cardiovascular system is connected and pulsations of blood vessels must have originated from the heart. The results using dogs, also indicated that there is a relationship between the cessation of the pulsations in the retinal blood vessels and the cessation of the heart beat. Dogs were used as a benchmark by which all other mammals could be compared. Therefore this study indicates that it is possible to identify the cessation of the heart using the cessation of the pulsations in the retinal blood vessels

    Retinal blood vessels extraction using probabilistic modelling

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    © 2014 Kaba et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.This article has been made available through the Brunel Open Access Publishing Fund.The analysis of retinal blood vessels plays an important role in detecting and treating retinal diseases. In this review, we present an automated method to segment blood vessels of fundus retinal image. The proposed method could be used to support a non-intrusive diagnosis in modern ophthalmology for early detection of retinal diseases, treatment evaluation or clinical study. This study combines the bias correction and an adaptive histogram equalisation to enhance the appearance of the blood vessels. Then the blood vessels are extracted using probabilistic modelling that is optimised by the expectation maximisation algorithm. The method is evaluated on fundus retinal images of STARE and DRIVE datasets. The experimental results are compared with some recently published methods of retinal blood vessels segmentation. The experimental results show that our method achieved the best overall performance and it is comparable to the performance of human experts.The Department of Information Systems, Computing and Mathematics, Brunel University

    Blood vessels and their construction in the cavities of pulmonary tuberculosis

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    First of all, we investigated the origin, the construction and distribution of the bronchial arteries and veins in adult rabbits, and then observed various changes of the blood vessels in experimental cavities and caseous foci and also studied the effects of streptomycin and isoniazide on the blood vessels of the cavity wall. The summary findings of the present experiments are described in the following. 1) In ten out of the fifteen rabbits emloyed, the bronchial artery originates from the right supreme intercostal artery; in three cases, in addition to this origin, it originates also from the left supreme intercostal artery; and in another case from the intercostal thoracic artery; while in the remaining one from the arc of the aorta. 2) The bronchial veins are divided into the extra-pulmonary and the intra-pulmonary veins. The former arises from the submucous blood vessels located in the proximal part of the third bronchus, and running along with the bronchial artery, finally empties into the superior Vena cava; while the latter, originating from the submucous capillaries in the distal part of the third bronchus, and after anastomosing with one another in the capsule of the bronchus, is communicated with the pulmonary veins. 3) In the caseous foci, although blood vessels are obliterated, capillaries are newly formed around the main trunks of the pulmonary artery and vein as well as around their residual branches. 4) These caseous foci are supplied with arterial blood from the bronchial arteries, the blood vessels in the bronchial wall, and the newlyformed vessels of pulmonary arterial origin. 5) The capillaries in the cavity wall are classified into three types according to their origins; namely, Type I, those regenerating from fine branches of the pulmonary vessels; Type &#8545;, those regenerating from the main trunk of the pulmonary vessels; and Type &#8546;, those regenerating from the bronchial artery situated in the orifice of the drainage bronchus. 6) The tuberculous cavities only in the orifice of the drainage bronchus receive an abundant supply of arterial blood directly from the bronchial artery, but those in other regions receive a scanty blood supply indirectly from the anastomoses between the bronchial artery, its sister vessels and the pulmonary artery. 7) The regeneration of blood vessels in tuberculous foci has been confirmed to occur not only in the bronchial artery and its sister blood vessels but also in the pulmonary artery and vein as well. 8) The constructions of blood vessels in the cavities treated with streptomycin or isoniazide present no significant difference from those of the control. 9) The regeneration of blood vessels and hyperemia in the cavity wall of the cases treated with streptomycin present no significant difference from those observed in the control, but the cases treated with isoniazide show marked hyperemia, newly-formed vessels, and occasional bleedings.</p

    Blood Vessels Under the Microscope

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    This paper looks at blood vessels. All humans and animals have blood vessels, including your pet rabbit or dog, a whale or a giraffe! We need blood vessels to stay alive. This paper answers many questions, including what blood vessels are used for and why we need them. It looks at how and why blood vessels grow and what they look like. It also explores what happens when things go wrong with blood vessels and if blood vessels are ever bad for us. So, if you want to know how many miles of blood vessels there are in your body, learn about problems astronauts have in space, see real blood vessels through a microscope, or learn how to keep your blood vessels healthy, you are reading the right article

    The innervation of the small blood vessels

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    Thesis (M.A.)--Boston University, 193

    Angiogenesis: A Model of Cell Differentiation

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    Angiogenesis is the formation of blood vessels, and is of great importance in the growth of tumours. Attempts have been made to desgin experiments in petri-dishes that mimic the 'Conditions of tumour growth. The first of the experiments is the 'matrigel' assay. Matrigel provides a matrix for the endothelial cells to grow on, and contains all the nutrients that the cells need. It is found that in the matrigel assay blood vessels didn't form, although some transient strucutres formed at early times in the experiment. The second experiment is the 'biocure' assay. In this experiment the petri dish is filled with both endothelial and fibroblast cells. The fibroblasts form a strucutal supporting network for the endothelial cells. Tubules resembling blood-vessels formed after about ten days in the biocure asssay. The process of cell differentiation is thought to be important in the growth of blood vessels. Cells can sense that they are part of a blood vessel, and change their shape to form tubules. Also it is likely that they change their chemical messaging properties, and their abilities to bind to other endothelial cells. A model is developed that describes cell differentiation, and separates cells into different classes. For simplicity the spatial distribution of cells in different classes is ignored. Using simple population dynamics, a set of coupled non-linear ODEs is developed to describe the dynamics of the system. The system is found to have two different long-time states, one corresponding to the formation of blood vessels and one where vessels did not form. The ratio of the cell proliferation rate to the cell maturity rate (the time it takes to realise that it is part of a blood vessel) is critical in determining which is the final state of the system

    Angiotensinergic innervation of rat and human mesenteric resistant blood vessels

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    In contrast to the current believe that angiotensin II (Ang II) only interacts with the sympathetic nervous system (SNS) as a circulating hormone, we document here the existence of an endogenous renin-angiotensin system (RAS) in the sympathetic coeliac ganglion and the angiotensinergic innervation with mesenteric resistant blood vessels. Our findings indicate that Ang II is synthesized inside the neurons of sympathetic coeliac ganglion and may act as an endogenous neurotransmitter locally on the mesenteric resistant blood vessels

    Intraoperative detection of blood vessels with an imaging needle during neurosurgery in humans

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    Intracranial hemorrhage can be a devastating complication associated with needle biopsies of the brain. Hemorrhage can occur to vessels located adjacent to the biopsy needle as tissue is aspirated into the needle and removed. No intraoperative technology exists to reliably identify blood vessels that are at risk of damage. To address this problem, we developed an “imaging needle” that can visualize nearby blood vessels in real time. The imaging needle contains a miniaturized optical coherence tomography probe that allows differentiation of blood flow and tissue. In 11 patients, we were able to intraoperatively detect blood vessels (diameter, \u3e500 μm) with a sensitivity of 91.2% and a specificity of 97.7%. This is the first reported use of an optical coherence tomography needle probe in human brain in vivo. These results suggest that imaging needles may serve as a valuable tool in a range of neurosurgical needle interventions
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