Leaf-Inspired Authentically Complex Microvascular Networks for Deciphering Biological Transport Process

2019 ◽  
Vol 11 (35) ◽  
pp. 31627-31637 ◽  
Author(s):  
Marco E. Miali ◽  
Marianna Colasuonno ◽  
Salvatore Surdo ◽  
Roberto Palomba ◽  
Rui Pereira ◽  
...  
Keyword(s):  
Transport Process ◽  
Biological Transport ◽  
Microvascular Networks

scholarly journals A two-lane mechanism for selective biological ammonium transport

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Gordon Williamson ◽  
Gaetan Dias Mirandela ◽  
Giulia Tamburrino ◽  
Melanie Boeckstaens ◽  
Adriana Bizior ◽  
...  
Keyword(s):  
Transport Process ◽  
Dual Problem ◽  
Functional Complementation ◽  
Ammonium Transport ◽  
Biological Transport ◽  
Transporter Family ◽  
The Family ◽  
Highly Hydrophobic ◽  
Dynamics Simulations ◽  
Competing Ions

The transport of charged molecules across biological membranes faces the dual problem of accommodating charges in a highly hydrophobic environment while maintaining selective substrate translocation. A particular controversy has existed around the mechanism of ammonium exchange by the ubiquitous Amt/Mep/Rh transporter family, an essential process in all kingdoms of life. Here, using a combination of SSME electrophysiology, yeast functional complementation, and extended molecular dynamics simulations, we reveal a unique two-lane pathway for electrogenic NH4+transport in two archetypal members of the family. The pathway underpins a mechanism by which charged H+and neutral NH3 are carried separately across the membrane after NH4+deprotonation. This mechanism defines a new principle of achieving transport selectivity against competing ions in a biological transport process.

scholarly journals A Quasi Random Walk to Model a Biological Transport Process

2013 ◽  
Vol 17 (1) ◽  
pp. 125-137 ◽  
Author(s):  
Peter Keller ◽  
Sylvie Rœlly ◽  
Angelo Valleriani
Keyword(s):  
Random Walk ◽  
Transport Process ◽  
Biological Transport

scholarly journals A two-lane mechanism for selective biological ammonium transport

2019 ◽  
Author(s):  
Gordon Williamson ◽  
Giulia Tamburrino ◽  
Gaëtan Dias Mirandela ◽  
Mélanie Boeckstaens ◽  
Marcus Bage ◽  
...  
Keyword(s):  
Transport Process ◽  
Dual Problem ◽  
Functional Complementation ◽  
Ammonium Transport ◽  
Biological Transport ◽  
Transporter Family ◽  
The Family ◽  
Highly Hydrophobic ◽  
Dynamics Simulations ◽  
Competing Ions

AbstractThe transport of charged molecules across biological membranes faces the dual problem of accommodating charges in a highly hydrophobic environment while maintaining selective substrate translocation. A particular controversy has existed around the mechanism of ammonium exchange by the ubiquitous Amt/Mep/Rh transporter family, an essential process in all kingdoms of life. Here, using a combination of electrophysiology, yeast functional complementation and extended molecular dynamics simulations, we reveal a unique two-lane pathway for electrogenic NH4+ transport in two archetypal members of the family. The pathway underpins a mechanism by which charged H+ and neutral NH3 are carried separately across the membrane after NH4+ deprotonation. This mechanism defines a new principle of achieving transport selectivity against competing ions in a biological transport process.

EFFICACY OF SALICYLIC AND ASCORBIC ACIDS TO REDUCE THE EFFECT OF TRANSPORT STRESS ON LIVE WEIGHT, SOME BLOOD CHARACTERISTICS AND INTESTINAL VILLI OF BROILER CHICKENS

2020 ◽  
Vol 51 (4) ◽  
pp. 1074-1081
Author(s):  
Al obaydy & et al.
Keyword(s):  
Ascorbic Acid ◽  
Drinking Water ◽  
Transport Process ◽  
Live Weight ◽  
Cholesterol Concentration ◽  
Control Treatment ◽  
Intestinal Villi ◽  
Slaughter House ◽  
Transport Stress ◽  
Financial Losses

This experiment was conducted and aimed to reducing mortality and losing the weight of birds transported to the slaughter house through reducing or Transport stress removal and thus to reduce financial losses. 150 birds used almost equal weights that were divided into three treatment groups and by five replicates for each treatment is control treatment (T1) without giving anything and treatment with salicylic acid concentration 1 g / liter of drinking water (T2) and treatment with ascorbic acid (T3) concentration 0.5 g / Liter of drinking water provided 24 hours before its transport. The transport process resulted in a highly significant decrease (P ≤ 0.01) in body weight in treatment T1 as it reached 4.66%, while it reached 1.68 and 1.09% in treatment T2 and T3, respectively. The transport process led to an increase in body temperature, H / L ratio, the concentration of glucose, aspartate transaminase (AST) and alanine transaminase (ALT) in the blood serum, as the transport process led to a very significant decrease (P ≤ 0.01) in the cholesterol concentration, Uric acid, intestinal villi length and crypts depth. T2 and T3 treatments showed their ability to reduce transport stress, especially T3, where they outperformed T1 in most traits. It is concluded from the study that adding ascorbic acid by 0.5 g / L drinking water 24 hours before transporting the chicks to the slaughter house reduces the transport stress and lessen financial losses, so it is recommended to use it.

scholarly journals Calixresorcin[4]arene-Mediated Transport of Pb(II) Ions Through Polymer Inclusion Membrane

Membranes ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 285
Author(s):  
Joanna Konczyk ◽  
Wojciech Ciesielski
Keyword(s):  
Activation Energy ◽  
Transport Process ◽  
Optimal Conditions ◽  
Inclusion Membrane ◽  
Polymer Inclusion Membrane ◽  
Membrane Effect ◽  
Feed Phase ◽  
Ion Carrier ◽  
Feed Effect ◽  
Nitrate Solutions

A facilitated transport of Pb(II) through polymer inclusion membrane (PIM) containing 1,8,15,22-tetra(1-heptyl)-calixresorcin[4]arene and its tetra- and octasubstituted derivatives containing phosphoryl, thiophosphoryl or ester groups as an ion carrier was investigated. The efficiency of Pb(II) removal from aqueous nitrate solutions was considered as a function of the composition of membrane (effect of polymer, plasticizer, and carrier), feed (effect of initial metal concentration and presence of other metal ions) and stripping phases, and temperature of the process conducting. Two kinetic models were applied for the transport description. The highest Pb(II) ions removal efficiency was obtained for the membrane with tetrathiophosphorylated heptyl-calixresorcin[4]arene as an ion carrier. The activation energy value, found from Eyring plot to be equal 38.7 ± 1.3 kJ/mol, suggests that the transport process is controllable both by diffusion and chemical reaction. The competitive transport of Pb(II) over Zn(II), Cd(II), and Cr(III) ions across PIMs under the optimal conditions was also performed. It was found that the Cr(III) ions’ presence in the feed phase disturb effective re-extraction of Pb(II) ions from membrane to stripping phase. Better stability of PIM-type than SLM-type membrane was found.

scholarly journals A modular microfluidic system based on a multilayered configuration to generate large-scale perfusable microvascular networks

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Tao Yue ◽  
Da Zhao ◽  
Duc T. T. Phan ◽  
Xiaolin Wang ◽  
Joshua Jonghyun Park ◽  
...  
Keyword(s):  
Large Scale ◽  
Circulatory System ◽  
Vertical Direction ◽  
Microfluidic System ◽  
Vital Role ◽  
Microvascular Networks ◽  
Biological Studies ◽  
Wide Range ◽  
High Flexibility

AbstractThe vascular network of the circulatory system plays a vital role in maintaining homeostasis in the human body. In this paper, a novel modular microfluidic system with a vertical two-layered configuration is developed to generate large-scale perfused microvascular networks in vitro. The two-layer polydimethylsiloxane (PDMS) configuration allows the tissue chambers and medium channels not only to be designed and fabricated independently but also to be aligned and bonded accordingly. This method can produce a modular microfluidic system that has high flexibility and scalability to design an integrated platform with multiple perfused vascularized tissues with high densities. The medium channel was designed with a rhombic shape and fabricated to be semiclosed to form a capillary burst valve in the vertical direction, serving as the interface between the medium channels and tissue chambers. Angiogenesis and anastomosis at the vertical interface were successfully achieved by using different combinations of tissue chambers and medium channels. Various large-scale microvascular networks were generated and quantified in terms of vessel length and density. Minimal leakage of the perfused 70-kDa FITC-dextran confirmed the lumenization of the microvascular networks and the formation of tight vertical interconnections between the microvascular networks and medium channels in different structural layers. This platform enables the culturing of interconnected, large-scale perfused vascularized tissue networks with high density and scalability for a wide range of multiorgan-on-a-chip applications, including basic biological studies and drug screening.

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