Search results for "Perfusion"
showing 10 items of 714 documents
VEGF-B-induced vascular growth leads to metabolic reprogramming and ischemia resistance in the heart
2014
Abstract Angiogenic growth factors have recently been linked to tissue metabolism. We have used genetic gain‐ and loss‐of function models to elucidate the effects and mechanisms of action of vascular endothelial growth factor‐B (VEGF‐B) in the heart. A cardiomyocyte‐specific VEGF‐B transgene induced an expanded coronary arterial tree and reprogramming of cardiomyocyte metabolism. This was associated with protection against myocardial infarction and preservation of mitochondrial complex I function upon ischemia‐reperfusion. VEGF‐B increased VEGF signals via VEGF receptor‐2 to activate Erk1/2, which resulted in vascular growth. Akt and mTORC1 pathways were upregulated and AMPK downregulated, …
Capillary enlargement, not sprouting angiogenesis, determines beneficial therapeutic effects and side effects of angiogenic gene therapy.
2010
Aims Currently, it is still unclear which mechanisms drive metabolic benefits after angiogenic gene therapy. The side-effect profile of efficient angiogenic gene therapy is also currently incompletely understood. In this study, the effects of increasing doses of adenoviral (Ad) vascular endothelial growth factor-A (VEGF-A) were evaluated on vascular growth, metabolic benefits, and systemic side effects. Methods and results Adenoviral vascular endothelial growth factor-A or AdLacZ control was injected intramuscularly (109–1011 vp/mL) or intra-arterially (5 × 1011 vp/mL) into rabbit ( n = 102) hindlimb muscles and examined 6 or 14 days later. Blood flow, tissue oedema, metabolic benefits, and…
Quantitative Bestimmung der Hirnperfusion mit Hilfe der digitalen Subtraktionsangiographie (DSA)
1990
In a search for a reliable and relatively non-invasive method for quantifying cerebral perfusion, we examined the possible role of DSA. By using special software, it is possible to demonstrate vascular morphology and obtain functional data concerning blood flow. Regions of interest are used for obtaining time-density curves and these are evaluated by a formula designed by Meier and Zierler. Perfusion through the arterial territory in both cerebral hemispheres was correlated with the clinical symptoms of the patients and with the morphological findings. Difficulties and problems are described and discussed.
Degradation of phosphatidylethanol counteracts the apparent phospholipase D-mediated formation in heart and other organs.
2003
Phosphatidylalcohols, such as phosphatidylethanol (PEth), are formed from phosphatidylcholine in the presence of a primary alcohol (e.g., ethanol). This 'transphosphatidylation' reaction is used as specific phospholipase D (PLD) assay. Accumulation of PEth in tissues is recognized as a reliable measure of PLD activity, as PEth is allegedly metabolically stable. The general validity of this assumption was reinvestigated in isolated rat heart, small intestine and brain slices. The half-times of 3H-PEth degradation (labelled with 3H-myristic acid and preformed by ethanol exposure for 30 min) were about 1 h in heart and small intestine, but 17 h in brain. As the formation of PEth is superimpose…
Hierarchical imaging and computational analysis of three-dimensional vascular network architecture in the entire postnatal and adult mouse brain
2021
The formation of new blood vessels and the establishment of vascular networks are crucial during brain development, in the adult healthy brain, as well as in various diseases of the central nervous system. Here, we describe a step-by-step protocol for our recently developed method that enables hierarchical imaging and computational analysis of vascular networks in postnatal and adult mouse brains. The different stages of the procedure include resin-based vascular corrosion casting, scanning electron microscopy, synchrotron radiation and desktop microcomputed tomography imaging, and computational network analysis. Combining these methods enables detailed visualization and quantification of t…
Hyperspectral imaging in perfusion and wound diagnostics – methods and algorithms for the determination of tissue parameters
2018
Abstract Blood perfusion is the supply of tissue with blood, and oxygen is a key factor in the field of minor and major wound healing. Reduced perfusion of a wound bed or transplant often causes various complications. Reliable methods for an objective evaluation of perfusion status are still lacking, and insufficient perfusion may remain undiscovered, resulting in chronic processes and failing transplants. Hyperspectral imaging (HSI) represents a novel method with increasing importance for clinical practice. Therefore, methods, software and algorithms for a new HSI system are presented which can be used to observe tissue oxygenation and other parameters that are of importance in supervising…
Elimination of Parathion by Hemoperfusion in Severe E 605 ForteR Intoxication in Vivo
1978
Severe parathion (P) intoxication results in complete inhibition of cholinesterase activity and toxic accumulation of acetylcholine. Besides these well known biochemical changes, there is evidence of direct toxic effects on the cardio-vascular system which may prove fatal due to an excess of P.
Mutes gļotādas mikrocirkulācijas novērtējums izmantojot attēlvides fotopletizmogrāfiju
2019
Manipulācijas ar smaganām ir kļuvušas par standarta procedūrām zobārstniecībā rosinot nepieciešamību pēc smaganu funkcionālām izvērtēšanas metodēm. It īpaši tādēļ, ka smaganu klīniskā aina nevienmēr atspoguļo to funkcionālo stāvokli un morfoloģiskās īpatnības var nomaskēt funkcionālos traucējumus. Vietējā anestēzija ir neatņemama zobārstniecības procedūra, kas novērš pacienta diskomfortu manipulāciju laikā, taču dažreiz tā var radīt arī nevēlamās blakusparādības vai pat komplikācijas, kam ir vairāki iemesli (lielās devas, individuālā jutība uz kādu no anestēzijas komponentu, traucējumi pulpas un smaganu asins apgādē, vai pat neirotoksicitāte). Līdz ar to devas samazināšana ir ļoti svarīga, …
Ischämietoleranz der Rattenleber durch alpha-Liponsäure
2003
Ischemia reperfusion injury (IRI) represents a major clinical problem in liver resection and transplantation. The present work investigated the potential of α-lipoic-acid (LA), a well established drug in the therapy of diabetes, to reduce IRI of the rat liver in vivo. Two groups were chosen: one group with injection of 500 μmol α-lipoic acid 15 min before clamping of the left and median liver lobes for 90 min, the other with injection of NaCl 0,9%. Reperfusion was carried out for 1 h and 7 days. The results showed that a-lipoic acid reduced IRI. LDH, α-GST and lipid peroxidation were significantly decreased in the LA-group after 1 h reperfusion indicating less cell death during reperfusion.…
High performance of intravoxel incoherent motion diffusion MRI in detecting viral hepatitis-b induced liver fibrosis.
2019
Background: Recently a small cohort study demonstrated that intravoxel incoherent motion (IVIM) diffusion MRI can detect early stage liver fibrosis. Using modified IVIM data acquisition parameters, the current study aims to confirm this finding. Methods: Twenty-six healthy volunteers, three patients of chronic viral hepatitis-b but without fibrosis and one mild liver steatosis subject, and 12 viral hepatitis-b patients with fibrosis (stage 1–2=7, stage 3–4=5) were included in this study. With a 1.5-T MR scanner and respiration-gating, IVIM diffusion imaging was acquired using a single-shot echo-planar sequence with a b -value series of 2, 0, 1, 15, 20, 30, 45, 50, 60, 80, 100, 200, 300, 600…