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Lymph Flow (lymph + flow)
Selected AbstractsNew method for evaluation of lung lymph flow rate with intact lymphatics in anaesthetized sheepACTA PHYSIOLOGICA, Issue 2 2006T. Naito Abstract Aim:, Lung lymph has commonly been studied using a lymph fistula created by tube cannulation into the efferent duct of the caudal mediastinal node in sheep. In this method, the tail region of the caudal mediastinal node is resected and the diaphragm is cauterized to exclude systemic lymph contamination, and cannulation is performed into one of the multiple efferent ducts originating from the caudal mediastinal node. Moreover, the pumping activity of lymphatics might be diminished by cannulation. Therefore, the purpose of the study was to evaluate the flow rate of lung lymph with maintenance of intact lymphatic networks around the caudal mediastinal node to the thoracic duct in sheep. Methods:, An ultrasound transit-time flow meter was used to measure lung lymph flow. The thoracic duct was clamped just above the diaphragm and the flow probe was attached to the thoracic duct just after the last junction with an efferent duct from the caudal mediastinal node. The lung lymph flow rate was measured at baseline and under conditions of lung-oedema formation. Results:, The baseline lung lymph flow rate in our model was three- to sixfold greater than values obtained with the cannulation method. With oedema-formation, the lung lymph flow rate was the same as that measured using cannulation. Conclusion:, The lung lymph flow was unexpectedly large under the conditions of the study, and our data suggest that the drainage effect of lymphatics is significant as a safety factor against pulmonary oedema formation. [source] Arnold Heller and the lymph pumpACTA PHYSIOLOGICA, Issue 3 2005K. Aukland Abstract This article reviews studies on lymph propulsion in the lymph vessels by active contraction of the vessels, first described by Arnold Heller in 1869 in German language, and here translated into English. His observations were first confirmed by Beatrice Carrier (1926) and Howard Flory et al. (1927), and several groups were active up to World war II. Few publications appeared in the period 1940--1960, followed by increasing activity and development of new experimental techniques for use both in various experimental animals and in humans. Recently it has been shown that passive lymph flow may add to active propulsion. Both mechanisms depend on lymph formation, i.e. the uptake of interstitial fluid by the initial lymph vessels which is still not well understood. [source] Enteric-formulated lactoferrin was more effectively transported into blood circulation from gastrointestinal tract in adult ratsEXPERIMENTAL PHYSIOLOGY, Issue 6 2006Takashi Takeuchi We have previously demonstrated that intestinally infused bovine lactoferrin (bLF) is transported into the blood circulation via the lymphatic pathway, not via the portal circulation. Therefore, in the present study, we further investigated whether intragastrically infused enteric-formulated bLF (EF-bLF) was more efficiently absorbed than bLF from the intestine in adult rats. The rats were randomly divided into three groups: 30 and 300 mg kg,1 non-enteric-formulated bLF (non-EF-bLF) groups and a 30 mg kg,1 EF-bLF group. Thoracic lymph was collected from a thoracic lymph duct under general anaesthesia. Bovine lactoferrin was infused into the stomach or duodenal lumen via a needle for a period of over 1 min in a volume of 1 ml kg,1. The bLF transported into the lymph was assayed quantitatively by double-antibody enzyme-linked immunosorbent assay (ELISA). Following the intragastric administration of bLF, the three groups showed almost the same lymph flow, but the bLF concentration in the lymph fluid in the EF-bLF group increased significantly and peaked 3 h after administration. With intraduodenal administration, the bLF concentration in the lymph fluid of the higher non-EF-bLF group was significantly higher than those of the other groups. The amount of absorbed bLF in the EF-bLF group was, however, about 10 times higher than that in the lower non-EF-bLF group, when it was administered intragastrically. These data show that enteric-formulated bLF is less susceptible to gastric pepsin and is more efficiently absorbed from the intestine than is non-enteric-formulated bLF. [source] Adaptation of Mesenteric Collecting Lymphatic Pump Function Following Acute Alcohol IntoxicationMICROCIRCULATION, Issue 7 2010FLAVIA M. SOUZA-SMITH Please cite this paper as: Souza-Smith, Kurtz, Molina and Breslin (2010). Adaptation of Mesenteric Collecting Lymphatic Pump Function Following Acute Alcohol Intoxication. Microcirculation17(7), 514,524. Abstract Objective:, Acute alcohol intoxication increases intestinal lymph flow by unknown mechanisms, potentially impacting mucosal immunity. We tested the hypothesis that enhanced intrinsic pump function of mesenteric lymphatics contributes to increased intestinal lymph flow during alcohol intoxication. Methods:, Acute alcohol intoxication was produced by intragastric administration of 30% alcohol to conscious, unrestrained rats through surgically implanted catheters. Time-matched controls received either no bolus, vehicle, or isocaloric dextrose. Thirty minutes after alcohol administration, rats were anesthetized and mesenteric collecting lymphatics were isolated and cannulated to study intrinsic pumping parameters. In separate experiments, mesenteric lymphatics were isolated to examine direct effects of alcohol on intrinsic pump activity. Results:, Lymphatics isolated from alcohol-intoxicated animals displayed significantly decreased CF compared to the dextrose group, elevated SVI versus all other groups, and decreased myogenic responsiveness compared to sham. Elevating pressure from 2 to 4 cm H2O increased the volume flow index 2.4-fold in the alcohol group versus 1.4-fold for shams. Isolated lymphatics exposed to 20 mM alcohol had reduced myogenic tone, without changes in CF or SVI. Conclusions:, Alcohol intoxication enhances intrinsic pumping by mesenteric collecting lymphatics. Alcohol directly decreases lymphatic myogenic tone, but effects on phasic contractions occur by an unidentified mechanism. [source] Flow in Lymphatic Networks: Interaction between Hepatic and Intestinal Lymph VesselsMICROCIRCULATION, Issue 4 2001RANDOLPH H. STEWART ABSTRACT Objective: Lymph from both the liver and intestine flows into the cisterna chyli. We hypothesized that increasing liver lymph flow would increase cisterna chyli pressure and, thereby, decrease intestinal lymph flow, potentiating intestinal edema formation. Methods: Anesthetized dogs were instrumented to measure and manipulate portal vein pressure and cisterna chyli pressure. The effects of directly increasing portal pressure with and without directly increasing cisterna chyli pressure on intestinal wet-to-dry ratio and intestinal ascites formation rate were determined. Target values for portal and cisterna chyli pressures were determined following elevation of inferior vena caval pressure to levels seen in patients with obstructive caval disease. Results: Direct elevation of portal pressure (Pport) alone to 17.5 mm Hg caused a significant increase in intestinal wet-to-dry ratio (3.98 ± 0.24 vs. 3.40 ± 0.43) and the rate of ascites formation (0.36 ± 0.12 vs. 0.05 ± 0.03 mL/g dry wt/h). Simultaneous direct elevation of cisterna chyli pressure to 6.0 mm Hg and Pport to 17.5 mm Hg caused further increases in intestinal wet-to-dry ratio (5.52 ± 1.20) and ascites formation (0.57 ± 0.11 mL/g dry wt./h). Conclusions: Inferior vena caval hypertension increases liver lymph flow that elevates cisterna chyli pressure, which inhibits intestinal lymph flow and augments intestinal edema formation. [source] Temperature-related fluid extravasation during cardiopulmonary bypass: An analysis of filtration coefficients and transcapillary pressuresACTA ANAESTHESIOLOGICA SCANDINAVICA, Issue 1 2002J. K. Heltne Background: Cardiopulmonary bypass (CPB) as used for cardiac surgery and for rewarming individuals suffering deep accidental hypothermia is held responsible for changes in microvascular fluid exchange often leading to edema and organ dysfunction. The purpose of this work is to improve our understanding of fluid pathophysiology and to explore the implications of the changes in determinants of transcapillary fluid exchange during CPB with and without hypothermia. This investigation might give indications on where to focus attention to reduce fluid extravasation during CPB. Methods: Published data on "Starling variables" as well as reported changes in fluid extravasation, tissue fluid contents and lymph flow were analyzed together with assumed/estimated values for variables not measured. The analysis was based on the Starling hypothesis where the transcapillary fluid filtration rate is given by: JV=Kf[Pc,Pi,,(COPp,COPi)]. Here Kf is the capillary filtration coefficient, , the reflection coefficient, P and COP are hydrostatic and colloid osmotic pressures, and subscript ,c' refers to capillary, ,i` to the interstitium and `p' to plasma. Results and conclusion: The analysis indicates that attempts to limit fluid extravasation during normothermic CPB should address primarily changes in Kf, while changes in both Kf and Pc must be considered during hypothermic CPB. [source] Near-infrared lymphatic imaging demonstrates the dynamics of lymph flow and lymphangiogenesis during the acute versus chronic phases of arthritis in miceARTHRITIS & RHEUMATISM, Issue 7 2010Quan Zhou Objective To develop an in vivo imaging method to assess lymphatic draining function in the K/BxN mouse model of inflammatory arthritis. Methods Indocyanine green, a near-infrared fluorescent dye, was injected intradermally into the footpads of wild-type mice, mouse limbs were illuminated with an 806-nm near-infrared laser, and the movement of indocyanine green from the injection site to the draining popliteal lymph node (LN) was recorded with a CCD camera. Indocyanine green near-infrared images were analyzed to obtain 5 measures of lymphatic function across time. Images of K/BxN arthritic mice and control nonarthritic littermates were obtained at 1 month of age, when acute joint inflammation commenced, and again at 3 months of age, when joint inflammation became chronic. Lymphangiogenesis in popliteal LNs was assessed by immunochemistry. Results Indocyanine green and its transport within lymphatic vessels were readily visualized, and quantitative measures were derived. During the acute phase of arthritis, the lymphatic vessels were dilated, with increased indocyanine green signal intensity and lymphatic pulses, and popliteal LNs became fluorescent quickly. During the chronic phase, new lymphatic vessels were present near the foot. However, the appearance of indocyanine green in lymphatic vessels was delayed. The size and area of popliteal LN lymphatic sinuses progressively increased in the K/BxN mice. Conclusion Our findings indicate that indocyanine green near-infrared lymphatic imaging is a valuable method for assessing the lymphatic draining function in mice with inflammatory arthritis. Indocyanine green,near-infrared imaging of K/BxN mice identified 2 distinct lymphatic phenotypes during the acute and chronic phase of inflammation. This technique can be used to assess new therapies for lymphatic disorders. [source] Therapeutic management of neonatal chylous ascites: report of a case and review of the literatureACTA PAEDIATRICA, Issue 9 2010Belma Saygili Karagol Abstract Congenital chylous ascites is a rare condition seen in the neonatal period and the data on pathogenesis and treatment modalities are limited. In this article, we report a case of neonate with chylous ascites and review the therapeutic management procedures on chylous ascites in childhood. We present our experience in the diagnosis and treatment of this condition. Conclusion:, Medium-chain triglycerides (MCT)-based diet can be tried as a first option in chylous ascites treatment. In resistant or unresponsive cases, somatostatin along with TPN can have use in closing the lymphatic leakage or relieving the symptoms effectively and rapidly. Conventional regimens including enteral feeding with MCT-based formula can then be re-administered as a maintenance treatment after reduction of lymph flow with the use of total parenteral nutrition (TPN) and somatostatin infusion combination. Patient-specific approach should be attempted for chylous ascites caused by various disorders and started as soon as possible. [source] | |||||||||||||