Regulation of Zn2+ Uptake from the Gastrointestinal Tract of a Marine Teleost, the Winter Flounder (Pseudopleuronectes americanus)

1983 ◽  
Vol 40 (S2) ◽  
pp. s197-s205 ◽  
Author(s):  
M. A. Shears ◽  
G. L. Fletcher
Keyword(s):  
Digestive Tract ◽  
The Body ◽  
Winter Flounder ◽  
Marine Teleost ◽  
Absorption Process ◽  
Pseudopleuronectes Americanus ◽  
Intravenous Injections ◽  
Rapid Accumulation ◽  
Gastrointestinal Uptake

The gastrointestinal uptake of Zn2+ was studied in winter flounder (Pseudopleuronectes americanus) using an in situ technique. The entire digestive tract was capable of absorbing Zn2+, with the uppermost portion of the intestine having the highest and the stomach the lowest capacity. A seasonal study revealed that the capacity of the digestive tract to absorb Zn2+ was greatest during the summer months. At least two steps appeared to be involved in the absorption process, the first a rapid accumulation of Zn2+ by the tissue, and the second a slower transfer into the body. The amount of Zn2+ absorbed increased with increasing loads of Zn2+ in the lumen; the transfer mechanism(s) was not saturated at the highest Zn2+ loads tested. Zn2+ uptake was inhibited in the presence of Cu2+, Cd2+, Co2+, Cr2+, Ni2+, Fe3+, Mn2+, and Hg2+. The capacity of the digestive tract to absorb Zn2+ was not affected by feeding the flounder a high-Zn2+ diet or by increasing body Zn2+ loads by intravenous injections. It is suggested that elimination mechanisms may play a greater role in maintaining Zn2+ homeostasis than controlling gastrointestinal uptake.

Digenean (Trematoda) populations in winter flounder (Pseudopleuronectes americanus) from Passamaquoddy Bay, New Brunswick, Canada

1985 ◽  
Vol 63 (7) ◽  
pp. 1699-1705 ◽  
Author(s):  
J. S. Scott
Keyword(s):  
New Brunswick ◽  
Alimentary Tract ◽  
Feeding Activity ◽  
The Body ◽  
Winter Flounder ◽  
Differential Migration ◽  
Pseudopleuronectes Americanus ◽  
Length Frequency ◽  
Frequency Distributions ◽  
Passamaquoddy Bay

Examination of monthly samples of winter flounder (Pseudopleuronectes americanus) from Passamaquoddy Bay revealed seven digenean parasites (Genolinea laticauda, Podocotyle atomon, Stenakron vetustum, Fellodistomum furcigerum, Derogenes varicus, Lecithaster gibbosus, and Steganoderma formosum) in the alimentary tract and two metacercariae (Stephanostomum baccatum and Cryptocotyle lingua) in the body surface tissues and gills. Prevalence of alimentary tract parasites ranged from 0.2 in S. formosum to 39.8 in P. atomon and intensity ranged from 1.5 for D. varicus to 7.0 for S. formosum (one fish). Monthly and seasonal levels of prevalence varied: high in spring and autumn and low in summer and winter for most species. Prevalence and length-frequency distributions of the parasites did not support differential migration by size group or diminishing feeding activity from spring to winter in winter flounder, as proposed in other studies.

scholarly journals Mechanisms responsible for the enhanced pumping capacity of the in situ winter flounder heart (Pseudopleuronectes americanus)

2007 ◽  
Vol 293 (5) ◽  
pp. R2112-R2119 ◽  
Author(s):  
Paula C. Mendonça ◽  
A. Gaylene Genge ◽  
Eric J. Deitch ◽  
A. Kurt Gamperl
Keyword(s):  
Cardiac Output ◽  
Power Output ◽  
High Volume ◽  
Filling Pressure ◽  
Winter Flounder ◽  
Mass Ratio ◽  
Pseudopleuronectes Americanus ◽  
Output Pressure

In situ Starling and power output curves and in vitro pressure-volume curves were determined for winter flounder hearts, as well as the hearts of two other teleosts (Atlantic salmon and cod). In situ maximum cardiac output was not different between the three species (∼62 ml·min−1·kg−1). However, because of the small size of the flounder heart, maximum stroke volume per milliliter per gram ventricle was significantly greater (2.3) compared with cod (1.7) and salmon (1.4) and is the highest reported for teleosts. The maximum power output of the flounder heart (7.6 mW/g) was significantly lower than that measured in the salmon (9.7) and similar to the cod (7.8) but was achieved at a much lower output pressure (4.9 vs. 8.0 and 6.2 kPa, respectively). Although the flounder heart could not perform resting levels of cardiac function at subambient pressures, it was much more sensitive to filling pressure, a finding supported by pressure-volume curves, which showed that the flounder's heart chambers were more compliant. Finally, we report that the flounder's bulbus:ventricle mass ratio (0.59) was significantly higher than in the cod (0.37) and salmon (0.22). These data, which support previous studies suggesting that the flatfish cardiovascular system is a high-volume, low-pressure design, show that vis-à-fronte filling is not important in flatfish, and that some fish can achieve high levels of cardiac output by vis-à-tergo filling alone; and suggest that a large compliant bulbus assists the flounder heart in delivering extremely large stroke volumes at pressures that do not become limiting.

Tissue distribution of fish antifreeze protein mRNAs

1992 ◽  
Vol 70 (4) ◽  
pp. 810-814 ◽  
Author(s):  
Zhiyuan Gong ◽  
Garth L. Fletcher ◽  
Choy L. Hew
Keyword(s):  
Northern Blot Analysis ◽  
Antifreeze Protein ◽  
The Body ◽  
Winter Flounder ◽  
Type I ◽  
Pseudopleuronectes Americanus ◽  
Sea Raven ◽  
Hemitripterus Americanus ◽  
Afp Mrna ◽  
Distribution Of Fish

The presence of fish antifreeze protein (AFP) mRNA was examined in a variety of tissues from the winter flounder (Pseudopleuronectes americanus), sea raven (Hemitripterus americanus), and ocean pout (Macrozoarces americanus), each of which contains one of the three known AFP types. Northern blot analysis indicates that whereas the AFP mRNA is restricted to liver in sea raven (type II AFP), significant amounts of mRNA are present in many other tissues in both winter flounder (type I) and ocean pout (type III). These results indicate that in sea raven, antifreeze protein synthesis only occurs in the liver, whereas in the ocean pout and winter flounder, synthesis occurs in many tissues throughout the body. These investigations are relevant to understanding the mode of action of these polypeptides.

The relationship between metallothionein and intestinal zinc absorption in the winter flounder

1984 ◽  
Vol 62 (11) ◽  
pp. 2211-2220 ◽  
Author(s):  
M. A. Shears ◽  
G. L. Fletcher
Keyword(s):  
Molecular Weight ◽  
Zinc Uptake ◽  
Winter Flounder ◽  
Zinc Binding ◽  
Low Molecular Weight ◽  
Zinc Absorption ◽  
Marine Teleost ◽  
Pseudopleuronectes Americanus ◽  
Chromatographic Techniques ◽  
The Relationship

Chromatographic techniques were used to investigate the presence of zinc-binding proteins in the intestinal mucosal cytosols of a marine teleost, the winter flounder (Pseudopleuronectes americanus). A low molecular weight, zinc-binding protein, characterized as metallothionein, was isolated from the intestinal cytosols of zinc-injected flounder. Metallothionein synthesis was induced in the intestine of the flounder by parenteral injections of zinc. However, studies conducted to assess the involvement of metallothionein in gastrointestinal zinc uptake indicated that its presence in the intestinal cytosol was not associated with any enhancement or depression of zinc uptake. These findings contrast with current hypotheses concerning metallothionein function in mammalian intestines.

Melanophore distribution within the integumentary tissues of two teleost species, Pseudopleuronectes americanus and Gasterosteus aculeatus form leiurus

1978 ◽  
Vol 56 (4) ◽  
pp. 526-535 ◽  
Author(s):  
Derek Burton
Keyword(s):  
Sexual Dimorphism ◽  
Gasterosteus Aculeatus ◽  
The Body ◽  
Winter Flounder ◽  
Dorsal Skin ◽  
Pseudopleuronectes Americanus ◽  
Skin Structure ◽  
Teleost Species ◽  
Dermal Layer ◽  
White Spots

In winter flounder, dermal melanophores are prominent chromatic components in the skin of the entire upper surface, and their arrangement is affected by imbrication of the ctenoid scales. Epidermal melanophores are also prominent over most of the body upper skin, scale imbrication having relatively little effect on their arrangement. Epidermal melanophores occur only sparsely on the fins and head skin, and are virtually absent from white spots of flounder disruptive patterns. In stickleback, epidermal melanophores were not observed. Melanophores with thin processes form a superficial dermal layer in the dorsal skin of the head and body of stickleback, and along the fin dermal supports. Melanophores with broad, wedge-like, processes form an extensive and continuous deep dermal layer in most of the body skin, which lacks scales, and on the operculum. Imbrication of the small number of lateral bony plates behind the operculum in leiurus sticklebacks does not greatly affect the melanophore arrangement. The skin structure of both species shows sexual dimorphism, but the respective melanophore layers are strongly developed in each sex.

Scaffolds for Drug Delivery in Tissue Engineering

2008 ◽  
Vol 1 (2) ◽  
pp. 113-123 ◽  
Author(s):  
Vikas V. Gaikwad ◽  
Abasaheb B. Patil ◽  
Madhuri V. Gaikwad
Keyword(s):  
Drug Delivery ◽  
Tissue Engineering ◽  
Heart Diseases ◽  
Cartilage Regeneration ◽  
Tissue Growth ◽  
The Body ◽  
Patient Specific ◽  
In Situ Gel ◽  
Heart Muscle Cells

Scaffolds are used for drug delivery in tissue engineering as this system is a highly porous structure to allow tissue growth.  Although several tissues in the body can regenerate, other tissue such as heart muscles and nerves lack regeneration in adults. However, these can be regenerated by supplying the cells generated using tissue engineering from outside. For instance, in many heart diseases, there is need for heart valve transplantation and unfortunately, within 10 years of initial valve replacement, 50–60% of patients will experience prosthesis associated problems requiring reoperation. This could be avoided by transplantation of heart muscle cells that can regenerate. Delivery of these cells to the respective tissues is not an easy task and this could be done with the help of scaffolds. In situ gel forming scaffolds can also be used for the bone and cartilage regeneration. They can be injected anywhere and can take the shape of a tissue defect, avoiding the need for patient specific scaffold prefabrication and they also have other advantages. Scaffolds are prepared by biodegradable material that result in minimal immune and inflammatory response. Some of the very important issues regarding scaffolds as drug delivery systems is reviewed in this article.

scholarly journals Ferromagnetic soft catheter robots for minimally invasive bioprinting

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Cheng Zhou ◽  
Youzhou Yang ◽  
Jiaxin Wang ◽  
Qingyang Wu ◽  
Zhuozhi Gu ◽  
...  
Keyword(s):  
Minimally Invasive ◽  
The Body ◽  
Magnetic Actuation ◽  
Internal Organs ◽  
Planar Surfaces ◽  
Reinforced Polymer ◽  
Direct Fabrication ◽  
Digitally Controlled

AbstractIn vivo bioprinting has recently emerged as a direct fabrication technique to create artificial tissues and medical devices on target sites within the body, enabling advanced clinical strategies. However, existing in vivo bioprinting methods are often limited to applications near the skin or require open surgery for printing on internal organs. Here, we report a ferromagnetic soft catheter robot (FSCR) system capable of in situ computer-controlled bioprinting in a minimally invasive manner based on magnetic actuation. The FSCR is designed by dispersing ferromagnetic particles in a fiber-reinforced polymer matrix. This design results in stable ink extrusion and allows for printing various materials with different rheological properties and functionalities. A superimposed magnetic field drives the FSCR to achieve digitally controlled printing with high accuracy. We demonstrate printing multiple patterns on planar surfaces, and considering the non-planar surface of natural organs, we then develop an in situ printing strategy for curved surfaces and demonstrate minimally invasive in vivo bioprinting of hydrogels in a rat model. Our catheter robot will permit intelligent and minimally invasive bio-fabrication.

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