scholarly journals Limited effects of increased CO2 and temperature on metal and radionuclide bioaccumulation in a sessile invertebrate, the oyster Crassostrea gigas

2015 ◽  
Vol 73 (3) ◽  
pp. 753-763 ◽  
Author(s):  
Murat Belivermiş ◽  
Michel Warnau ◽  
Marc Metian ◽  
François Oberhänsli ◽  
Jean-Louis Teyssié ◽  
...  
Keyword(s):  
Crassostrea Gigas ◽  
Uptake Rate ◽  
Soft Tissues ◽  
Interactive Effect ◽  
Seawater Ph ◽  
The Pacific ◽  
Effects Of Ph ◽  
Uptake Rate Constant ◽  
In Vitro Simulation

Abstract This study investigated the combined effects of reduced pH and increased temperature on the capacities of the Pacific cupped oyster Crassostrea gigas to bioconcentrate radionuclide and metals. Oysters were exposed to dissolved radiotracers (110mAg, 241Am, 109Cd, 57Co, 54Mn, and 65Zn) at three pH (7.5, 7.8, 8.1) and two temperatures (21 and 24°C) under controlled laboratory conditions. Although calcifying organisms are recognized as particularly vulnerable to ocean acidification, the oyster did not accumulate differently the studied metals when exposed under the different pH conditions. However, temperature alone or in combination with pH somewhat altered the bioaccumulation of the studied elements. At pH 7.5, Cd was accumulated with an uptake rate constant twofold higher at 24°C than 21°C. Bioaccumulation of Mn was significantly affected by an interactive effect between seawater pH and temperature, with a decreased uptake rate at pH 7.5 when temperature increased (27 ± 1 vs. 17 ± 1 d−1 at 21 and 24°C, respectively). Retention of Co and Mn tended also to decrease at the same pH with decreasing temperature. Neither pH nor temperature affected strongly the elements distribution between shell and soft tissues. Significant effects of pH were found on the bioaccessibility of Mn, Zn, and 241Am during experimental in vitro simulation of human digestion.

scholarly journals Distribution and Antimicrobial Activity of Ciprofloxacin in Human Soft Tissues

1999 ◽  
Vol 43 (5) ◽  
pp. 1307-1309 ◽  
Author(s):  
Martin Brunner ◽  
Ursula Hollenstein ◽  
Simon Delacher ◽  
Dorothea Jäger ◽  
Rainer Schmid ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Serum Concentration ◽  
Healthy Volunteers ◽  
Intravenous Administration ◽  
Soft Tissues ◽  
Total Serum ◽  
Drug Concentrations ◽  
Simulation Based ◽  
In Vitro Simulation

ABSTRACT Interstitial ciprofloxacin concentrations in soft tissues were measured by microdialysis following intravenous administration of 200 mg to each of eight healthy volunteers. Interstitial ciprofloxacin concentrations were significantly lower than corresponding total serum drug concentrations; the interstitium-to-serum concentration ratios ranged from 0.55 to 0.73. An in vitro simulation based on interstitial pharmacokinetics showed a substantially lower antimicrobial activity than did the simulation based on serum pharmacokinetics. Thus, ciprofloxacin concentrations at the site of effect may be subinhibitory although effective concentrations are attained in serum.

Biological and biomedical applications of collagenous biomaterials

1990 ◽  
Vol 48 (3) ◽  
pp. 856-857
Author(s):  
Yasushi P. Kato ◽  
Michael G. Dunn ◽  
Frederick H. Silver ◽  
Arthur J. Wasserman
Keyword(s):  
Biomedical Applications ◽  
Soft Tissues ◽  
Collagen Fibers ◽  
Bone Collagen ◽  
Cover Slip ◽  
Fibroblast Migration ◽  
Cellular Expression ◽  
Defect Repair

Collagenous biomaterials have been used for growing cells in vitro as well as for augmentation and replacement of hard and soft tissues. The substratum used for culturing cells is implicated in the modulation of phenotypic cellular expression, cellular orientation and adhesion. Collagen may have a strong influence on these cellular parameters when used as a substrate in vitro. Clinically, collagen has many applications to wound healing including, skin and bone substitution, tendon, ligament, and nerve replacement. In this report we demonstrate two uses of collagen. First as a fiber to support fibroblast growth in vitro, and second as a demineralized bone/collagen sponge for radial bone defect repair in vivo.For the in vitro study, collagen fibers were prepared as described previously. Primary rat tendon fibroblasts (1° RTF) were isolated and cultured for 5 days on 1 X 15 mm sterile cover slips. Six to seven collagen fibers, were glued parallel to each other onto a circular cover slip (D=18mm) and the 1 X 15mm cover slip populated with 1° RTF was placed at the center perpendicular to the collagen fibers. Fibroblast migration from the 1 x 15mm cover slip onto and along the collagen fibers was measured daily using a phase contrast microscope (Olympus CK-2) with a calibrated eyepiece. Migratory rates for fibroblasts were determined from 36 fibers over 4 days.

Effect of pH and inhibitors on beta-amyloid fibril assembly

1996 ◽  
Vol 54 ◽  
pp. 752-753
Author(s):  
Beverly E. Maleeff ◽  
Timothy K. Hart ◽  
Stephen J. Wood ◽  
Ronald Wetzel
Keyword(s):  
Amyloid Fibril ◽  
Peptide Fragment ◽  
Hydrophobic Peptides ◽  
Amyloid Fibril Formation ◽  
Effects Of Ph ◽  
Severity Of The Disease ◽  
Kinetics Of ◽  
The Brain

Alzheimer's disease is characterized post-mortem in part by abnormal extracellular neuritic plaques found in brain tissue. There appears to be a correlation between the severity of Alzheimer's dementia in vivo and the number of plaques found in particular areas of the brain. These plaques are known to be the deposition sites of fibrils of the protein β-amyloid. It is thought that if the assembly of these plaques could be inhibited, the severity of the disease would be decreased. The peptide fragment Aβ, a precursor of the p-amyloid protein, has a 40 amino acid sequence, and has been shown to be toxic to neuronal cells in culture after an aging process of several days. This toxicity corresponds to the kinetics of in vitro amyloid fibril formation. In this study, we report the biochemical and ultrastructural effects of pH and the inhibitory agent hexadecyl-N-methylpiperidinium (HMP) bromide, one of a class of ionic micellar detergents known to be capable of solubilizing hydrophobic peptides, on the in vitro assembly of the peptide fragment Aβ.

3D Culture Modelling: An Emerging Approach for Translational Cancer Research in Sarcomas

2020 ◽  
Vol 27 (29) ◽  
pp. 4778-4788 ◽  
Author(s):  
Victoria Heredia-Soto ◽  
Andrés Redondo ◽  
José Juan Pozo Kreilinger ◽  
Virginia Martínez-Marín ◽  
Alberto Berjón ◽  
...  
Keyword(s):  
High Throughput Screening ◽  
Cancer Biology ◽  
Soft Tissues ◽  
Three Dimensional ◽  
3D Culture ◽  
Resistance Mechanisms ◽  
In Vitro Models ◽  
Tumour Spheroids ◽  
Current Therapies

Sarcomas are tumours of mesenchymal origin, which can arise in bone or soft tissues. They are rare but frequently quite aggressive and with a poor outcome. New approaches are needed to characterise these tumours and their resistance mechanisms to current therapies, responsible for tumour recurrence and treatment failure. This review is focused on the potential of three-dimensional (3D) in vitro models, including multicellular tumour spheroids (MCTS) and organoids, and the latest data about their utility for the study on important properties for tumour development. The use of spheroids as a particularly valuable alternative for compound high throughput screening (HTS) in different areas of cancer biology is also discussed, which enables the identification of new therapeutic opportunities in commonly resistant tumours.

scholarly journals Ultra-strong bio-glue from genetically engineered polypeptides

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Chao Ma ◽  
Jing Sun ◽  
Bo Li ◽  
Yang Feng ◽  
Yao Sun ◽  
...  
Keyword(s):  
Soft Tissues ◽  
Covalent Bond ◽  
Genetically Engineered ◽  
Supramolecular Interactions ◽  
Molar Ratio ◽  
High Adhesion ◽  
Strong Adhesion ◽  
Order Of Magnitude

AbstractThe development of biomedical glues is an important, yet challenging task as seemingly mutually exclusive properties need to be combined in one material, i.e. strong adhesion and adaption to remodeling processes in healing tissue. Here, we report a biocompatible and biodegradable protein-based adhesive with high adhesion strengths. The maximum strength reaches 16.5 ± 2.2 MPa on hard substrates, which is comparable to that of commercial cyanoacrylate superglue and higher than other protein-based adhesives by at least one order of magnitude. Moreover, the strong adhesion on soft tissues qualifies the adhesive as biomedical glue outperforming some commercial products. Robust mechanical properties are realized without covalent bond formation during the adhesion process. A complex consisting of cationic supercharged polypeptides and anionic aromatic surfactants with lysine to surfactant molar ratio of 1:0.9 is driven by multiple supramolecular interactions enabling such strong adhesion. We demonstrate the glue’s robust performance in vitro and in vivo for cosmetic and hemostasis applications and accelerated wound healing by comparison to surgical wound closures.

scholarly journals Quantification of assembly forces during creation of head-neck taper junction considering soft tissue bearing: a biomechanical study

Arthroplasty ◽  
2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Toni Wendler ◽  
Torsten Prietzel ◽  
Robert Möbius ◽  
Jean-Pierre Fischer ◽  
Andreas Roth ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Work Experience ◽  
Soft Tissues ◽  
Force Sensor ◽  
Biomechanical Study ◽  
Measuring System ◽  
Wide Range ◽  
Head Neck

Abstract Background All current total hip arthroplasty (THA) systems are modular in design. Only during the operation femoral head and stem get connected by a Morse taper junction. The junction is realized by hammer blows from the surgeon. Decisive for the junction strength is the maximum force acting once in the direction of the neck axis, which is mainly influenced by the applied impulse and surrounding soft tissues. This leads to large differences in assembly forces between the surgeries. This study aimed to quantify the assembly forces of different surgeons under influence of surrounding soft tissue. Methods First, a measuring system, consisting of a prosthesis and a hammer, was developed. Both components are equipped with a piezoelectric force sensor. Initially, in situ experiments on human cadavers were carried out using this system in order to determine the actual assembly forces and to characterize the influence of human soft tissues. Afterwards, an in vitro model in the form of an artificial femur (Sawbones Europe AB, Malmo, Sweden) with implanted measuring stem embedded in gelatine was developed. The gelatine mixture was chosen in such a way that assembly forces applied to the model corresponded to those in situ. A study involving 31 surgeons was carried out on the aforementioned in vitro model, in which the assembly forces were determined. Results A model was developed, with the influence of human soft tissues being taken into account. The assembly forces measured on the in vitro model were, on average, 2037.2 N ± 724.9 N, ranging from 822.5 N to 3835.2 N. The comparison among the surgeons showed no significant differences in sex (P = 0.09), work experience (P = 0.71) and number of THAs performed per year (P = 0.69). Conclusions All measured assembly forces were below 4 kN, which is recommended in the literature. This could lead to increased corrosion following fretting in the head-neck interface. In addition, there was a very wide range of assembly forces among the surgeons, although other influencing factors such as different implant sizes or materials were not taken into account. To ensure optimal assembly force, the impaction should be standardized, e.g., by using an appropriate surgical instrument.

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