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Wearable Sensors for Blood Perfusion Monitoring in Patients with Diabetes Mellitus
Published in Andrey V. Dunaev, Valery V. Tuchin, Biomedical Photonics for Diabetes Research, 2023
Evgenii A. Zherebtsov, Elena V. Zharkikh, Yulia I. Loktionova, Angelina I. Zherebtsova, Viktor V. Sidorov, Alexander I. Krupatkin, Andrey V. Dunaev
After lymph leaks out of the LC, it enters the lymphatic postcapillary (LP), which has a basement membrane, valves that prevent retrograde lymph flow, and single myocytes, including those in the valve zone. The next section of the lymphatic bed consists of lymphatic vessels (LV), which have a three-layer wall with smooth muscles (contractile or collecting lymphatics). The part between two valves of the LV is called a lymphangion. Each lymphangion has its own pacemaker located near valve areas. Actually, the activity produced by the valves is the major driving force of lymph (the intrinsic mechanism of lymph flow). The mechanism underlying the pacemaker activity is associated with increased intravascular pressure and stretching of vascular smooth muscles. The lymphatic system acts as an extensive drainage network, which is not attached to the heart and serves to transport and absorb proteins and their complexes with other substance lymph from the intercellular spaces between the cells of tissues [9,10].
Structure of Initial and Collecting Lymphatic Vessels
Published in Waldemar L. Olszewski, Lymph Stasis: Pathophysiology, Diagnosis and Treatment, 2019
Each vascular segment between two valves represents a unit called lymphangion.64,65 The ability of collecting vessels to create muscular actions and to propel the lymph in one direction is based on the functional morphological properties of such a unit. The smooth muscular system of the tunica media is especially thick in the intervalvular portion, whereas it is poorly developed in the valve section (see Figure 18). The muscular fiber bundles are arranged in a more longitudinal fashion in the transitorial zone to the tunica intima and tunica adventitia and are more circularly oriented in the intermediate part. Close to the valve segment the pitch of the circular arrangement of fibers is steeper than in the middle zone between two valves. Due to the lack of muscle fibers the valve segment should be more extensible than the other parts of the vascular tube. In structural differentiation the lymphangion resembles small hearts. As a further feature of the vascular wall, the interlacing of muscle cells with the intimai and adventitial connective tissue has been regarded. A subtle aspect is that each lymphangion comprises only one valve-bearing section and the adjoining section with the muscular cuff, whereby the latter forms the base for the following lymphangion.66,87
Lymphatic disorders
Published in Professor Sir Norman Williams, Professor P. Ronan O’Connell, Professor Andrew W. McCaskie, Bailey & Love's Short Practice of Surgery, 2018
Professor Sir Norman Williams, Professor P. Ronan O’Connell, Professor Andrew W. McCaskie
Several different techniques of MLD have been described and the details are beyond the scope of this chapter. However, they all aim to evacuate fluid and protein from the interstitial space and stimulate lymphangion contraction, with decongestion of impaired lymphatic pathways and development of collateral routes. The therapist should perform MLD daily; they should also train the patient (and/or carer) to perform a simpler, modified form of massage termed simple lymphatic drainage (SLD). In the intensive phase, SLD supplements MLD and, once the maintenance phase is entered, SLD will carry on as daily massage.
The health effects of short fiber chrysotile and amphibole asbestos
Published in Critical Reviews in Toxicology, 2022
Riquet (2007) described the lymphatics of the lung as a visceral pleural network and a parenchymatous peri-bronchovascular plexus, located mainly in the connective tissue surrounding the airways and their bronchial artery vascular supply. Lymphatics originate from capillaries located between the alveolar walls and the interlobular, pleural, peribronchial, or perivascular connective sheets. They form lymphatic collecting vessels called “collectors.” The lymphatic collectors contain smooth muscles and one-way valves every 2–10 mm along their length. The segments within two valves, the lymphangions, act as a small pump, with smooth muscle contraction in one lymphangion forcing fluid into the next. The valves prevent retrograde flow. The visceral pleura lymphatic collectors course over the surface of the lung toward the lung hilum, where they generally anastomose with the lymphatic collectors of the peribronchovascular plexus (the latter, strictly speaking, being the bronchial lymphatics). They also can travel further along the bronchi and the lower part of the trachea without anastomosing and enter directly into the mediastinum (Lauweryns 1970; Lauweryns and Baert 1977; Riquet et al. 1989; Drake et al. 1991).
Risk factors for seroma formation after axillary lymph node dissection with special focus on the impact of early shoulder exercise
Published in Acta Oncologica, 2023
Gunilla Borg, Looket Dihge, Karin Johansson
When the lymph vessels have closed by themselves and started to develop new vessels [22,23] they will enable removal of the seroma from the operation area. It is well-known that exercises, particularly muscle contractions, can increase the flow, both in veins and lymph vessels [24,25]. Therefore, early start of exercise, twice daily, may be important to support the flow in regenerated vessels as well as in remaining vessels that are forced to transport a larger load of fluid than before the surgery, demanding a higher flow rate. Lymph vessels are also on their own, able to increase flow capacity by increased frequency of lymphangion pumping contractions, also supported by muscle contractions [24].