scholarly journals Evidence for continuity of interstitial spaces across tissue and organ boundaries in humans

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Odise Cenaj ◽  
Douglas H. R. Allison ◽  
Rami Imam ◽  
Briana Zeck ◽  
Lilly M. Drohan ◽  
...  
Keyword(s):  
The Body ◽  
Cell Trafficking ◽  
Molecular Signaling ◽  
Extracellular Matrix Components ◽  
Show Evidence ◽  
Tattoo Pigment ◽  
Flow Through ◽  
Macromolecular Component ◽  
Fibrous Tissues ◽  
Organ Boundaries

AbstractBodies have continuous reticular networks, comprising collagens, elastin, glycosaminoglycans, and other extracellular matrix components, through all tissues and organs. Fibrous coverings of nerves and blood vessels create structural continuity beyond organ boundaries. We recently validated fluid flow through human fibrous tissues, though whether these interstitial spaces are continuous through the body or discontinuous, confined within individual organs, remains unclear. Here we show evidence for continuity of interstitial spaces using two approaches. Non-biological particles (tattoo pigment, colloidal silver) were tracked within colon and skin interstitial spaces and into adjacent fascia. Hyaluronic acid, a macromolecular component of interstitial spaces, was also visualized. Both techniques demonstrate interstitial continuity within and between organs including within perineurium and vascular adventitia traversing organs and the spaces between them. We suggest that there is a body-wide network of fluid-filled interstitial spaces that has significant implications for molecular signaling, cell trafficking, and the spread of malignant and infectious disease.

scholarly journals Interstitial spaces are continuous across tissue and organ boundaries in humans

2020 ◽  
Author(s):  
Odise Cenaj ◽  
Douglas H. R. Allison ◽  
R Imam ◽  
Briana Zeck ◽  
Lilly M. Drohan ◽  
...  
Keyword(s):  
Fibrous Tissue ◽  
The Body ◽  
Cell Trafficking ◽  
Molecular Signaling ◽  
Extracellular Matrix Components ◽  
Tattoo Pigment ◽  
Flow Through ◽  
Macromolecular Component ◽  
Fibrous Tissues ◽  
Organ Boundaries

AbstractBodies have “reticular networks” comprising collagens, elastin, glycosaminoglycans, and other extracellular matrix components, that are continuous within and around all organs. Fibrous tissue coverings of nerves and blood vessels create structural continuity beyond organ boundaries. We recently described fluid flow through such human fibrous tissues. It remains unclear whether these interstitial spaces are continuous through the body or are discontinuous, confined within individual organs. We investigated IS continuity using two approaches. Non-biological particles (tattoo pigment, colloidal silver) were tracked within colon and skin interstitial spaces and into adjacent fascia. We also exploited hyaluronic acid, a macromolecular component of interstitial spaces. Both techniques demonstrate continuity of interstitial spaces within and across organ boundaries, including within perineurium and vascular adventitia traversing organs and the spaces between them. We suggest a body-wide network of fluid-filled interstitial spaces with significant implications for molecular signaling, cell trafficking, and the spread of malignant and infectious disease.

scholarly journals Keloidal pathophysiology: Current notions

2021 ◽  
Vol 7 ◽  
pp. 205951312098032
Author(s):  
Chenyu Huang ◽  
Rei Ogawa
Keyword(s):  
Web Of Science ◽  
English Literature ◽  
The Body ◽  
Mechanical Forces ◽  
Healthy Skin ◽  
Level Of Evidence ◽  
Extracellular Matrix Components ◽  
Keloid Formation ◽  
Mechanical Factors ◽  
Pathological Scar

Introduction: Keloids are pathological scars that are notorious for their chronic and relentless invasion into adjacent healthy skin, with commonly seen post-therapeutic recurrence after monotherapies. Methods: An English literature review on keloid pathophysiology was performed by searching the PubMed, Embase and Web of Science databases, to find out the up-to-date relevant articles. The level of evidence was evaluated based on the included studies with the highest level of evidence first. Results: Keloid morphology, signs, symptoms and the histopathological changes that occur in the local cells and extracellular matrix components are described. The theories on the pathophysiology of keloidogenesis that have been proposed to date are also covered; these include endocrinological, nutritional, vascular, and autoimmunological factors. In addition, we describe the local mechanical forces (and the mechanosignalling pathways by which these forces shape keloid cell activities) that promote keloid formation and determine the direction of invasion of keloids and the body sites that are prone to them. Conclusion: A better understanding of this pathological entity, particularly its mechanobiology, will aid the development of new diagnostic and therapeutic strategies for use in the clinic to prevent, reduce or even reverse the growth of this pathological scar. Lay Summary Keloids are skin scars that are famous for their chronic invasion into healthy skin, with commonly seen recurrence after surgeries. Cells such as lymphocytes, macrophages, mast cells and endothelial cells are involved in keloid growth. Particularly, endocrinological, nutritional, vascular, autoimmunological and mechanical factors actively take part in keloid progression.

Pressure-flow relations in coronary circulation

1990 ◽  
Vol 70 (2) ◽  
pp. 331-390 ◽  
Author(s):  
J. I. Hoffman ◽  
J. A. Spaan
Keyword(s):  
Coronary Vessels ◽  
Good Evidence ◽  
The Body ◽  
Vascular Compression ◽  
Exact Nature ◽  
Coronary Veins ◽  
Collapsible Tubes ◽  
External Pressures ◽  
Flow Through

The blood vessels that run on the surface of the heart and through its muscle are compliant tubes that can be affected by the pressures external to them in at least two ways. If the pressure outside these vessels is higher than the pressure at their downstream ends, the vessels may collapse and become Starling resistors or vascular waterfalls. If this happens, the flow through these vessels depends on their resistance and the pressure drop from their inflow to the pressure around them and is independent of the actual downstream pressure. In the first part of this review, the physics of collapsible tubes is described, and the possible occurrences of vascular waterfalls in the body is evaluated. There is good evidence that waterfall behavior is seen in collateral coronary arteries and in extramural coronary veins, but the evidence that intramural coronary vessels act like vascular waterfalls is inconclusive. There is no doubt that in systole there are high tissue pressures around the intramyocardial vessels, particularly in the subendocardial muscle of the left ventricle. The exact nature and values of the forces that act at the surface of the small intramural vessels, however, are still not known. We are not certain whether radial (compressive) or circumferential and longitudinal (tensile) stresses are the major causes of vascular compression; the role of collagen struts in modifying the reaction of vessel walls to external pressures is unknown but possibly important; direct examination of small subepicardial vessels has failed to show vascular collapse. One of the arguments in favor of intramyocardial vascular waterfalls has been that during a long diastole the flow in the left coronary artery decreases and reaches zero when coronary arterial pressure is still high: it can be as much as 50 mmHg in the autoregulating left coronary arterial bed and approximately 15-20 mmHg even when the vessels have been maximally dilated. These high zero flow pressures, especially during maximal vasodilatation, have been regarded as indicating a high back pressure to flow that is due to waterfall behavior of vessels that are exposed to tissue pressures.(ABSTRACT TRUNCATED AT 400 WORDS)

Rack Level Modeling of Air Flow Through Perforated Tile in a Data Center

2012 ◽  
Author(s):  
Vaibhav K. Arghode ◽  
Pramod Kumar ◽  
Yogendra Joshi ◽  
Thomas S. Weiss ◽  
Gary Meyer
Keyword(s):  
Data Center ◽  
Body Force ◽  
Air Flow ◽  
The Body ◽  
Physical Models ◽  
Cfd Modeling ◽  
Computational Time ◽  
Force Model ◽  
Flow Through ◽  
Tile Surface

Effective air flow distribution through perforated tiles is required to efficiently cool servers in a raised floor data center. We present detailed computational fluid dynamics (CFD) modeling of air flow through a perforated tile and its entrance to the adjacent server rack. The realistic geometrical details of the perforated tile, as well as of the rack are included in the model. Generally models for air flow through perforated tiles specify a step pressure loss across the tile surface, or porous jump model based on the tile porosity. An improvement to this includes a momentum source specification above the tile to simulate the acceleration of the air flow through the pores, or body force model. In both of these models geometrical details of tile such as pore locations and shapes are not included. More details increase the grid size as well as the computational time. However, the grid refinement can be controlled to achieve balance between the accuracy and computational time. We compared the results from CFD using geometrical resolution with the porous jump and body force model solution as well as with the measured flow field using Particle Image Velocimetry (PIV) experiments. We observe that including tile geometrical details gives better results as compared to elimination of tile geometrical details and specifying physical models across and above the tile surface. A modification to the body force model is also suggested and improved results were achieved.

The Peri-Renal Tissue of Protopterus A Contribution to the History of the Adrenal

1956 ◽  
Vol s3-97 (37) ◽  
pp. 123-154
Author(s):  
W. HOLMES ◽  
D. E. MOORHOUSE
Keyword(s):  
Small Diameter ◽  
Renal Tissue ◽  
Body Cavity ◽  
The Body ◽  
Round Cell ◽  
East African ◽  
Cell Tissue ◽  
Starting Point ◽  
Show Evidence ◽  
Eosinophil Granulocytes

The animal studied was the lungfish Protopterus aethiopicus; the investigation was histological and cytochemical, the material being freshly taken from East African lakes. The peri-renal tissue is a substantial organ which, because it surrounds the kidney, extends through the greater part of the body cavity. Those who have investigated its structure in recent years have considered it to be a haematopoietic organ. A wide variety of histological, histochemical, and haematological techniques was used. The organ is shown to contain five characteristic kinds of tissue; these are named: lipid, endothelial, pigmented, round-cell, and steroid tissue respectively. The lipid tissue is characterized by cytoplasmic liposomes--droplets containing phospholipid. In one type of cell, the ‘small lipid cell’, which may be related to the eosinophil granulocytes of the blood, the droplets have a relatively small diameter. In a second type, the ‘large lipid cell’, the droplets grow to a much larger diameter, and show evidence of cycles of activity involving increase and disappearance of the phospholipid. Histochemical interpretations are made difficult by the finding that this phospholipid does not colour with Sudan black. The endothelial tissue is composed of phagocytic (macrophage) cells some of which are elongated and line vascular sinusoids while others are spherical and contain larger inclusions. These inclusions have some lipid characteristics and may be a manifestation of the translocation of lipid within the organ. The pigmented tissue is composed of melanophores and of a second, round, type of cell which shows evidence of relationship with the macrophage system. Both kinds of cell contain ‘melanin’; the second also has inclusions with different histochemical properties. The round-cell tissue, found in nodules, has a general resemblance to lymphoid tissue. It is doubtful whether its cells are lymphocytes, but it has not been found possible to characterize them in any other way. The steroid tissue is composed of cells which react positively to the histochemical tests comprised in the ‘steroid repertoire’, as used in the study of the mammalian adrenal. Attention is drawn to technical difficulties which may have confused the study of the peri-renal tissue as a haematopoietic organ. The connexion between the lipid tissue and circulating granulocytes has features which distinguish it from the processes of granulocyte formation in the spleen. There are strong indications of an evolutionary connexion between peri-renal tissue and the cortex of the adrenal gland of higher animals. The lungfish may offer the best starting-point for the study of the comparative histology of the adrenal of tetrapods. The association between lipid, steroid, haematopoietic, macrophage, and pigment tissue has parallels in function in the complex interrelations of the mammalian adrenal.

Positioning and maintenance of embryonic body wall muscle attachments in C. elegans requires the mup-1 gene

Development ◽  
1991 ◽  
Vol 111 (3) ◽  
pp. 667-681 ◽  
Author(s):  
P.Y. Goh ◽  
T. Bogaert
Keyword(s):  
Extracellular Matrix ◽  
Body Wall ◽  
Early Stage ◽  
Muscle Growth ◽  
The Body ◽  
Body Wall Muscle ◽  
C Elegans ◽  
Extracellular Matrix Molecule ◽  
Extracellular Matrix Components ◽  
Body Wall Muscles

As part of a general study of genes specifying a pattern of muscle attachments, we identified and genetically characterised mutants in the mup-1 gene. The body wall muscles of early stage mup-1 embryos have a wild-type myofilament pattern but may extend ectopic processes. Later in embryogenesis, some body wall muscles detach from the hypodermis. Genetic analysis suggests that mup-1 has both a maternal and a zygotic component and is not required for postembryonic muscle growth and attachment. mup-1 mutants are suppressed by mutations in several genes that encode extracellular matrix components. We propose that mup-1 may encode a cell surface/extracellular matrix molecule required both for the positioning of body wall muscle attachments in early embryogenesis and the subsequent maintenance of these attachments to the hypodermis until after cuticle synthesis.

Application and In situ calibration of a pulsed-doppler flowmeter for blood flow measurement in crustaceans

1994 ◽  
Vol 74 (2) ◽  
pp. 455-458 ◽  
Author(s):  
C.N. Airriess ◽  
B.R. McMahon ◽  
I.J. McGaw ◽  
G.B. Bourne
Keyword(s):  
Blood Flow ◽  
Cardiac Output ◽  
The Body ◽  
Pulsed Doppler ◽  
Arterial Perfusion ◽  
Non Invasive ◽  
In Situ Calibration ◽  
Flow Through ◽  
Doppler Flowmeter

The pulsed-Doppler flowmeter permits continuous, non-invasive measurement of blood flow through several arteries simultaneously. Summation of volume flow rates through all arteries leaving the heart allows determination of cardiac output, stroke volume, and the percentage of cardiac output delivered to each region of the body. The use of this system for investigating changes in arterial perfusion as well as its calibration in situ are described.

scholarly journals Naked chancelloriids from the lower Cambrian of China show evidence for sponge-type growth

2018 ◽  
Vol 285 (1881) ◽  
pp. 20180296 ◽  
Author(s):  
Pei-Yun Cong ◽  
Thomas H. P. Harvey ◽  
Mark Williams ◽  
David J. Siveter ◽  
Derek J. Siveter ◽  
...  
Keyword(s):  
Lower Cambrian ◽  
Body Cavity ◽  
Body Plan ◽  
The Body ◽  
Phylogenetic Position ◽  
Axis Formation ◽  
Large Size ◽  
Show Evidence ◽  
Body Plan Evolution ◽  
Extinct Group

Chancelloriids are an extinct group of spiny Cambrian animals of uncertain phylogenetic position. Despite their sponge-like body plan, their spines are unlike modern sponge spicules, but share several features with the sclerites of certain Cambrian bilaterians, notably halkieriids. However, a proposed homology of these ‘coelosclerites' implies complex transitions in body plan evolution. A new species of chancelloriid, Allonnia nuda , from the lower Cambrian (Stage 3) Chengjiang Lagerstätte is distinguished by its large size and sparse spination, with modified apical sclerites surrounding an opening into the body cavity. The sclerite arrangement in A. nuda and certain other chancelloriids indicates that growth involved sclerite addition in a subapical region, thus maintaining distinct zones of body sclerites and apical sclerites. This pattern is not seen in halkieriids, but occurs in some modern calcarean sponges. With scleritome assembly consistent with a sponge affinity, and in the absence of cnidarian- or bilaterian-grade features, it is possible to interpret chancelloriids as sponges with an unusually robust outer epithelium, strict developmental control of body axis formation, distinctive spicule-like structures and, by implication, minute ostia too small to be resolved in fossils. In this light, chancelloriids may contribute to the emerging picture of high disparity among early sponges.

scholarly journals Fighting against Skin Aging

2018 ◽  
Vol 27 (5) ◽  
pp. 729-738 ◽  
Author(s):  
Shoubing Zhang ◽  
Enkui Duan
Keyword(s):  
Molecular Mechanisms ◽  
Treatment Strategies ◽  
Skin Aging ◽  
The Body ◽  
Aging Research ◽  
Functional Changes ◽  
Extracellular Matrix Components ◽  
Matrix Components ◽  
Aging Factors ◽  
Outer Environment

As the most voluminous organ of the body that is exposed to the outer environment, the skin suffers from both intrinsic and extrinsic aging factors. Skin aging is characterized by features such as wrinkling, loss of elasticity, laxity, and rough-textured appearance. This aging process is accompanied with phenotypic changes in cutaneous cells as well as structural and functional changes in extracellular matrix components such as collagens and elastin. In this review, we summarize these changes in skin aging, research advances of the molecular mechanisms leading to these changes, and the treatment strategies aimed at preventing or reversing skin aging.

Descriptions of spawning of the pouched lamprey (Geotria australis) in tanks and of morphological changes leading up to and following spawning

2020 ◽  
Vol 26 (3) ◽  
pp. 301 ◽  
Author(s):  
K. R. Paton ◽  
M. H. Cake ◽  
D. J. Bird ◽  
I. C. Potter
Keyword(s):  
Morphological Changes ◽  
The Body ◽  
Upstream Migration ◽  
Cell Stage ◽  
Spawning Period ◽  
Filtration System ◽  
Geotria Australis ◽  
In The Wild ◽  
Flow Through ◽  
Declining Species

The anadromous Geotria australis, one of only three lamprey species representing the early agnathan (jawless) stage of vertebrate evolution in Australia and New Zealand, is declining in abundance. Its adults were caught soon after they had entered rivers on their non-trophic upstream migration and maintained in laboratory tanks for 13–15 months through to spawning. As adult G. australis are susceptible to haemorrhagic septicaemia, they were treated prophylactically and maintained in 3-m3 aquaria supplied with a flow-through charcoal filtration system and UV steriliser. Air temperature and the light:dark regime were constantly adjusted to parallel those in the environment. Males developed the very large suctorial disc and gular pouch characteristic of maturity and both sexes matured at the same time as in the wild. While males frequently showed aggressive behaviour towards each other, the same male and female mated on several occasions. The male coiled around the female and, with his urogenital papilla close to the female’s cloaca, twisted and vibrated, leading to egg release. These eggs formed coagulated clusters as in the wild, with many progressing through to the eight-cell stage. Remarkably, numerous G. australis were still alive 95–392 days after the end of the short spawning period, and one male after a further 119 days. Postspawning survival would be facilitated inter alia by extensive proteolysis, reflected in a shortening of the body. The data in this paper emphasise that G. australis is a highly atypical lamprey and provides invaluable information for conserving this declining species.

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