scholarly journals Surface Modification of Hemoglobin-Based Oxygen Carriers Reduces Recognition by Haptoglobin, Immunoglobulin, and Hemoglobin Antibodies

Coatings ◽  
2019 ◽  
Vol 9 (7) ◽  
pp. 454 ◽  
Author(s):  
Ausanai Prapan ◽  
Nittiya Suwannasom ◽  
Chiraphat Kloypan ◽  
Saranya Chaiwaree ◽  
Axel Steffen ◽  
...  
Keyword(s):  
Surface Modification ◽  
Biomedical Applications ◽  
Binding Capacity ◽  
Surface Modifications ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Oxygen Binding ◽  
Oxygen Carriers ◽  
Surface Modified

Hemoglobin-based oxygen carriers (HBOCs) represent a propitious type of blood substitute to transport oxygen throughout the body while acting as a carrier in biomedical applications. However, HBOCs in blood are recognized and rapidly scavenged by the body’s innate immune systems. To overcome this problem, HBOCs require a surface modification that provides protection against detection and elimination in order to prolong their circulation time after administration. In this study, we investigated different surface modifications of hemoglobin submicron particles (HbMPs) by double/triple precipitation, as well as by adsorption of human serum albumin (HSA), hyaluronic acid (HA), and pluronic (Plu) to discover how diverse surface modifications influence the oxygen binding capacity and the binding of anti-hemoglobin (Hb) antibodies, immunoglobulin G (IgG), and haptoglobin (HP) to HbMPs. The particle size and zeta potential of the six types of HbMP modifications were analyzed by zeta sizer, confocal laser scanning microscopy, and transmission electron microscopy (TEM), and were compared to the unmodified HbMPs. The results revealed that all surface-modified HbMPs had a submicron size with a negative charge. A slight decrease in the oxygen binding capacity was noticed. The specific binding of anti-Hb antibodies, IgG, and HP to all surface-modified HbMPs was reduced. This indicates a coating design able to protect the particles from detection and elimination processes by the immune system, and should lead to a delayed clearance and the required and essential increase in half-life in circulation of these particles in order to fulfill their purpose. Our surface modification method reflects a promising strategy for submicron particle design, and can lead the way toward novel biomedical applications.

scholarly journals Electrophoretic Deposition of Carbon Nanotubes over TiO2Nanotubes: Evaluation of Surface Properties and Biocompatibility

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Jung Eun Park ◽  
Il Song Park ◽  
Tae Sung Bae ◽  
Min Ho Lee
Keyword(s):  
Mechanical Properties ◽  
Carbon Nanotubes ◽  
Corrosion Resistance ◽  
Surface Modification ◽  
Electrophoretic Deposition ◽  
Biomedical Applications ◽  
Controlled Drug Delivery ◽  
Chemical Durability ◽  
Surface Modified ◽  
Excellent Chemical

Titanium (Ti) is often used as an orthopedic and dental implant material due to its better mechanical properties, corrosion resistance, and excellent biocompatibility. Formation of TiO2nanotubes (TiO2NTs) on titanium is an interesting surface modification to achieve controlled drug delivery and to promote cell growth. Carbon nanotubes (CNTs) possess excellent chemical durability and mechanical strength. The use of CNTs in biomedical applications such as scaffolds has received considerable attention in recent years. The present study aims to modify the surface of titanium by anodizing to form TiO2NTs and subsequently deposit CNTs over it by electrophoretic deposition (EPD). Characteristic, biocompatibility, and apatite forming ability of the surface modified samples were evaluated. The results of the study reveal that CNTs coating on TiO2nanotubes help improve the biological activity and this type of surface modification is highly suitable for biomedical applications.

scholarly journals Morphological and morphometric study of pre-ovigerous and post-ovigerous adults of Tanaisia (Paratanaisia) bragai (Santos, 1934) (Digenea, Eucotylidae)

2017 ◽  
Vol 18 (2) ◽  
Author(s):  
Sthefane D'ávila ◽  
Pedro Paulo de Abreu Manso ◽  
Elizabeth Cristina de Almeida Bessa ◽  
Maria de Lurdes de Azevedo Rodrigues
Keyword(s):  
Light Microscopy ◽  
Confocal Laser Scanning Microscopy ◽  
Body Length ◽  
Laser Scanning ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Confocal Laser ◽  
Morphometric Study

The aim of this study was to obtain data on the morphology and morphometry of pre-ovigerous and post-ovigerous adults of the species Tanaisia (Paratanaisia) bragai, using confocal laser scanning microscopy to obtain tomographic images of the suckers and tegument. For morphometric analysis, 45 specimens (30 pre-ovigerous adults and 15 post-ovigerous adults) were measured with the aid of an ocular micrometer coupled to the objective of a photonic microscope. Pre-ovigerous and post-ovigerous adult individuals, stained with Mair carmalumen and mounted in permanent preparations, were analyzed by means of confocal laser scanning microscopy. Positive correlation was detected between the body length and ovary length of post-ovigerous adults (rs: 0.774; p<0.01), as well as between the body length and testes (rs: 0.604 and 0.659; p< 0.05), the body length and the length of uterus (rs: 0.839; p< 0,01) and between the ovary width and egg length (rs: 0.777; p<0.01). Morphological study of the pre-ovigerous adults demonstrated that the ovary and testes develop simultaneously before the development of the uterus and vitelline glands. The acetabulum was detected in pre-ovigerous adults stained with hematoxilin and observed using light microscopy. In these specimens, the acetabulum measured 36.7 ± 6.9 µm (25-50 µm) in width and 39.91 ± 6.8 µm (25-55 µm) in length. The acetabulum was not detected in post-ovigerous adults observed with light microscopy. However, this structure was detected using confocal miscrocopy. In the post-ovigerous specimens, the acetabulum presented a reduced size compared to the pre-ovigerous adults. This may imply that this structure has more functional significance in the larval and pre-ovigerous stages.

scholarly journals An integrative approach to the anatomy of Syllis gracilis Grube, 1840 (Annelida) using micro-computed X-ray tomography

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7251 ◽  
Author(s):  
Julio Parapar ◽  
Carlos Caramelo ◽  
María Candás ◽  
Xela Cunha-Veira ◽  
Juan Moreira
Keyword(s):  
3D Visualization ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Integrative Approach ◽  
Confocal Laser ◽  
Main Body ◽  
Micro Ct ◽  
Internal Anatomy ◽  
X Ray ◽  
Internal Body

Background The overall anatomy of the genus Syllis (Annelida: Syllidae) has been largely studied; however, an integrative approach considering different anatomical techniques has never been considered. Here, we use micro-computed X-ray tomography (micro-CT) to examine the internal anatomy of Syllis gracilis Grube, 1840, along with other widely available techniques. Methods We studied the anatomy of the marine annelid S. gracilis through an integrative approach, including micro-CT along with stereo and light compound microscopy (STM, LCM), scanning electron microscopy (SEM), confocal laser scanning microscopy (CLSM) and histological sectioning (HIS). In this manner, we evaluated the applicability of micro-CT for the examination of annelid anatomy by testing whether the images obtained make it possible to visualize the main body structures, in comparison with other current techniques, of the various elements of its internal anatomy. Results Overall external and internal body elements are clearly shown by the integrative use of all techniques, thus overcoming the limitations of each when studied separately.Any given method shows disparate results, depending on the body part considered. For instance, micro-CT provided good images of the external anatomy, including relevant characters such as the shape, length and number of articles of dorsal parapodial cirri. However, it is especially useful for the examination of internal anatomy, thus allowing for 3D visualization of the natural spatial arrangement of the different organs. The features best visualized are those of higher tissue density (i.e., body musculature, anterior parts of the digestive tract), particularly in 3D images of unstained specimens, whereas less electrodense tissues (i.e., the peritoneal lining of septa and nervous system) are less clearly visualized. The use of iodine stain with micro-CT has shown advantages against non-staining for the adequate observation of delicate elements of low density, such as the segmental organs, the connective between the ganglia, the ventral nerve cord and segmental nerves. Discussion Main external anatomical elements of S. gracilis are well shown with micro-CT, but images show lesser optical resolution and contrast when compared to micrographs provided by SEM and CLSM, especially for fine structural features of chaetae. Comparison of micro-CT and HIS images revealed the utility and reliability of the former to show the presence, shape and spatial disposition of most internal body organs; the resolution of micro-CT images at a cellular level is, however, much lower than that of HIS, which makes both techniques complementary.

Human Vascular Endothelial Cells in Primary Cell Culture for the Evaluation of Nanoparticle Bioadhesion

2006 ◽  
Vol 6 (9) ◽  
pp. 3303-3309 ◽  
Author(s):  
Christoph Löhbach ◽  
Dirk Neumann ◽  
Claus-Michael Lehr ◽  
Alf Lamprecht
Keyword(s):  
Drug Delivery ◽  
Cell Culture ◽  
Endothelial Cells ◽  
Covalent Binding ◽  
Particle Diameter ◽  
Fluorescence Emission ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Human Endothelial Cells ◽  
Surface Modified

Nanoparticles (NP) are employed in various therapeutic approaches for innovative drug delivery strategies. Among them, there is drug delivery to the brain and sustained release forms for intravenous drug delivery. In order to optimize drug carriers and to elucidate involved mechanisms such as bioadhesion and cellular uptake, NP were surface modified and analyzed for their interaction with human endothelial cells in cell culture. Fluorescently labeled NP of different diameters (50 to 1000 nm) were surface modified either by simple adsorption of chitosan or by covalent binding to the lectin ulex europaeus agglutinin and thereafter applied to human endothelial cells for different incubation periods. After incubation with NP the binding of NP was quantified directly by the fluorescence emission signals from the cell layers. In order to visualize the binding behaviour, NP were localized three-dimensionally in the cell layer by confocal laser scanning microscopy. Cell binding experiments in phosphate buffer were observed to be particle size dependent with the 50 nm NP showing the highest binding percentage over all experiments. Binding decreased with increasing particle diameter and shorter incubation interval. The adhesion was further enhanced by NP surface modifications in the order blank < chitosan < lectin. The presence of plasma proteins enhanced the adhesiveness of chitosan coated NP, while the binding of lectin coated NP was inhibited. Experiments at 4 °C indicated the involvement of an active process in the binding of NP to endothelial cells.

SURFACE MODIFICATION OF NITINOL BY CHEMICAL AND ELECTROCHEMICAL ETCHING

2013 ◽  
Vol 27 (19) ◽  
pp. 1341012 ◽  
Author(s):  
ZHENDI YANG ◽  
XIAOJIN WEI ◽  
PENG CAO ◽  
WEI GAO
Keyword(s):  
Surface Modification ◽  
Biomedical Applications ◽  
Cell Attachment ◽  
Electrochemical Etching ◽  
Nickel Content ◽  
Corrosion Property ◽  
X Ray ◽  
Ni Content ◽  
Etching Parameters ◽  
Surface Modified

In this paper, Nitinol, an equiatomic binary alloy of nickel and titanium, was surface modified for its potential biomedical applications by chemical and electrochemical etching. The main objective of the surface modification is to reduce the nickel content on the surface of Nitinol and simultaneously to a rough surface microstructure. As a result, better biocompatibility and better cell attachment would be achieved. The effect of the etching parameters was investigated, using scanning electron microscopy (SEM) equipped with energy dispersive X-ray spectrometry (EDX) and X-ray photoelectron spectrometry (XPS). The corrosion property of modified Nitinol surfaces was investigated by electrochemical work station. After etching, the Ni content in the surface layer has been reduced and the oxidation of Ti has been enhanced.

scholarly journals Ultrastructural, Confocal and Viscoelastic Characteristics of Whole Blood and Plasma After Exposure to Cadmium and Chromium Alone and in Combination: An Ex Vivo Study

2017 ◽  
Vol 43 (3) ◽  
pp. 1288-1300 ◽  
Author(s):  
Chantelle Venter ◽  
Hester Magdalena Oberholzer ◽  
Janette Bester ◽  
Mia-Jeanne van Rooy ◽  
Megan Jean Bester
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Blood Coagulation ◽  
Ex Vivo ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Ultrastructural Changes ◽  
Target System ◽  
Metal Exposure ◽  
Confocal Laser

Background/Aims: Heavy metal pollution is increasing in the environment, contaminating water, food and air supplies. This can be linked to many anthropogenic activities. Heavy metals are absorbed through the skin, inhalation and/or orally. Irrespective of the manner of heavy metal entry in the body, the blood circulatory system is potentially the first to be affected following exposure and adverse effects on blood coagulation can lead to associated thrombotic disease. Although the plasma levels and the effects of cadmium (Cd) and chromium (Cr) on erythrocytes and lymphocytes have been described, the environmental exposure to heavy metals are not limited to a single metal and often involves metal mixtures, with each metal having different rates of absorption, different cellular, tissue, and organ targets. Therefore the aim of this study is to investigate the effects of the heavy metals Cd and Cr alone and whether Cr synergistically increases the effect of Cd on physiological important processes such as blood coagulation. Methods: Human blood was exposed to the heavy metals ex vivo, and thereafter morphological analysis was performed with scanning electron- and confocal laser scanning microscopy (CLSM) in conjunction with thromboelastography®. Results: The erythrocytes, platelets and fibrin networks presented with ultrastructural changes, including varied erythrocytes morphologies, activated platelets and significantly thicker fibrin fibres in the metal-exposed groups. CLSM analysis revealed the presence of phosphatidylserine on the outer surface of the membranes of the spherocytic erythrocytes exposed to Cd and Cr alone and in combination. The viscoelastic analysis revealed only a trend that indicates that clots that will form after heavy metal exposure, will likely be fragile and unstable especially for Cd and Cr in combination. Conclusion: This study identified the blood as an important target system of Cd and Cr toxicity.

DOPAMINE SERVES AS A STABLE SURFACE MODIFIER FOR IRON OXIDE NANOPARTICLES

2013 ◽  
Vol 01 (02) ◽  
pp. 1350001 ◽  
Author(s):  
XIAOQIN CHI ◽  
XIAOMIN WANG ◽  
JUAN HU ◽  
LIRONG WANG ◽  
JINHAO GAO ◽  
...  
Keyword(s):  
Surface Modification ◽  
Iron Oxide ◽  
Iron Oxide Nanoparticles ◽  
Biomedical Applications ◽  
Ph Value ◽  
Detailed Examination ◽  
Blocking Temperature ◽  
Oxide Nanoparticles ◽  
Long Term Stability ◽  
Surface Modified

Iron oxide nanoparticles are an important class of nanomaterials in a broad range of biomedical applications because of their superparamagnetism and biocompatibility. The success of biomedical applications of iron oxide nanoparticles relies on the particles' surface functionalization, which requires robust and versatile surface anchors. Here, we report on a detailed examination of the dopamine-based surface modification of iron oxide nanoparticles. We used dopamine (2-(3,4-dihydroxyphenyl)ethylamine) and L-dopa (3,4-dihydroxy-L-phenylalanine) as two surface modifiers and chose Fe 2 O 3 hollow nanoparticles and Fe 3 O 4 nanoparticles as two representative substrates. Optical and TEM images showed that iron oxide nanoparticles dispersed very well in water after surface modification. The analysis of the UV-Vis spectra indicated that dopamine and L-dopa are stable after being immobilized on the surface of iron oxide nanoparticles when the pH value of the environment is about 7. The magnetic properties analysis further showed that the blocking temperature of the dopamine- or L-dopa-decorated iron oxide nanoparticles hardly changed over 20 days, confirming long-term stability of these surface modified nanoparticles. Cell assay indicated that these dopamine- or L-dopa-modified iron oxide nanoparticles were biocompatible. These results confirm that dopamine serves as a stable modifier and a robust anchor to functionalize iron oxide nanoparticles in biomedical applications.

scholarly journals Quantum Dot-Loaded Liposomes to Evaluate the Behavior of Drug Carriers after Oral Administration

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Kohei Tahara ◽  
Shiho Fujimoto ◽  
Fumihiko Fujii ◽  
Yuichi Tozuka ◽  
Takashi Jin ◽  
...  
Keyword(s):  
Quantum Dot ◽  
Oral Administration ◽  
Laser Scanning ◽  
Lipid Membrane ◽  
Drug Carriers ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Confocal Laser ◽  
Peptide Drug

We have developed submicron-sized liposomes modified with a mucoadhesive polymer to enhance peptide drug absorption after oral administration. Liposomal behavior in the gastrointestinal tract is a critical factor for effective peptide drug delivery. The purpose of this study was to prepare quantum dot- (QD-) loaded submicron-sized liposomes and examine liposomal behavior in the body after oral administration using in vivo fluorescence imaging. Two types of CdSe/CdZnS QDs with different surface properties were used: hydrophobic (unmodified) QDs and hydrophilic QDs with glutathione (GSH) surface modifications. QD- and GSH-QD-loaded liposomes were prepared by a thin film hydration method. Transmission electron microscopy revealed that QDs were embedded in the liposomal lipid bilayer. Conversely, GSH-QDs were present in the inner aqueous phase. Some of the GSH-QDs were electrostatically associated with the lipid membrane of stearylamine-bearing cationic liposomes. QD-loaded liposomes were detected in Caco-2 cells after exposure to the liposomes, and these liposomes were not toxic to the Caco-2 cells. Furthermore, we evaluated the in vivo bioadhesion and intestinal penetration of orally administered QD-loaded liposomes by observing the intestinal segment using confocal laser scanning microscopy.

Effect of chemical modification on slip resistance and mechanical properties of rubber

2015 ◽  
Vol 35 (2) ◽  
pp. 119-125
Author(s):  
Ranganathan Mohan ◽  
Raja Sundaresan ◽  
Bhabendra Nath Das
Keyword(s):  
Mechanical Properties ◽  
Surface Modification ◽  
Photoelectron Spectroscopy ◽  
Abrasion Resistance ◽  
Material Design ◽  
Surface Modifications ◽  
Vertical Force ◽  
Water Contact ◽  
Slip Resistance ◽  
Surface Modified

Abstract Shoe sole material, design, tread pattern and surface modifications influence slip resistance while walking and running. Thermoplastic styrene-butadine-styrene rubber, commercially known as TPR, is one of the materials widely used as shoe soles. This type of sole is subjected to chemical treatment known as halogenation to increase adhesion characteristic with the upper. The coefficient of friction (COF) is the ratio between the horizontal force and the vertical force when tested with the help of slip resistance test equipment SATRA STM 603. It is also known that footwear outsole surface modification affects COF at the footwear floor interfaces. In this study, plain TPR shoe sole samples were surface modified by treating with 2.0 wt% trichloroisocyanuric acid (TCI) in methyl ethyl ketone (MEK). The effect of surface modifications was studied by water contact angle measurements, Fourier transform infrared (FTIR) and X-ray photoelectron spectroscopy (XPS), surface roughness and scanning electron microscopy (SEM). The surface modified sole samples were also tested for other mechanical properties such as tensile strength, elongation at break, hardness and abrasion resistance to find out the extent of changes in those essential functional properties. It was observed that surface modification of TPR sole increased COF and reduced strength, elasticity and abrasion resistance properties. However, there was no significant change in hardness.

scholarly journals Serotonin Signalling in Flatworms: An Immunocytochemical Localisation of 5-HT7 Type of Serotonin Receptors in Opisthorchis felineus and Hymenolepis diminuta

Biomolecules ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1212
Author(s):  
Natalia Kreshchenko ◽  
Nadezhda Terenina ◽  
Artem Ermakov
Keyword(s):  
Nervous System ◽  
Serotonin Receptors ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Hymenolepis Diminuta ◽  
Confocal Laser ◽  
Muscle Fibres ◽  
Published Data ◽  
Opisthorchis Felineus ◽  
Nerve Cords

The study is dedicated to the investigation of serotonin (5-hydroxytryptamine, 5-HT) and 5-HT7 type serotonin receptor of localisation in larvae of two parasitic flatworms Opisthorchis felineus (Rivolta, 1884) Blanchard, 1895 and Hymenolepis diminuta Rudolphi, 1819, performed using the immunocytochemical method and confocal laser scanning microscopy (CLSM). Using whole mount preparations and specific antibodies, a microscopic analysis of the spatial distribution of 5-HT7-immunoreactivity(-IR) was revealed in worm tissue. In metacercariae of O. felineus 5-HT7-IR was observed in the main nerve cords and in the head commissure connecting the head ganglia. The presence of 5-HT7-IR was also found in several structures located on the oral sucker. 5-HT7-IR was evident in the round glandular cells scattered throughout the larva body. In cysticercoids of H. diminuta immunostaining to 5-НТ7 was found in flame cells of the excretory system. Weak staining to 5-HT7 was observed along the longitudinal and transverse muscle fibres comprising the body wall and musculature of suckers, in thin longitudinal nerve cords and a connective commissure of the central nervous system. Available publications on serotonin action in flatworms and serotonin receptors identification were reviewed. Own results and the published data indicate that the muscular structures of flatworms are deeply supplied by 5-HT7-IR elements. It suggests that the 5-HT7 type receptor can mediate the serotonin action in the investigated species and is an important component of the flatworm motor control system. The study of the neurochemical basis of parasitic flatworms can play an important role in the solution of fundamental problems in early development of the nervous system and the evolution of neuronal signalling components.

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