Filtry
wszystkich: 262
wybranych: 145
Filtry wybranego katalogu
Wyniki wyszukiwania dla: CONCENTRATION IN TISSUES
-
Novel Research on Biomedical Polyurethanes
PublikacjaThe variety of mechanical properties characterizes properly designed PURs. They may be biocompatible and reveal compatibility with blood, making them attractive materials for the fabrication of tissue scaffolds; however, like all synthetic materials, PURs don’t reveal sufficient biocompatibility. PURs may undergo certain chemical modifications (e.g., 1,4:3,6-dianhydro-D-sorbitol, ascorbic acid (AA), growth factors, covering with...
-
Applications of Raman spectroscopy for detection of selected substances in tissues
PublikacjaThis dissertation explores the applications of Raman spectroscopy for biological tissue analysis. Basics of Raman and surface-enhanced Raman spectroscopy (SERS) are described, along with an analysis of the literature on biodetection and non-invasive blood analysis with emphasis on glucose detection. Instrumentation for Raman measurements is described. The sources of noise and interferences occurring in biological tissue measurements...
-
Automatic system for optical parameters measurements of biological tissues
PublikacjaIn this paper a system allowing execution of automatic measurements of optical parameters of scattering materials in an efficient and accurate manner is proposed and described. The system is designed especially for measurements of biological tissues including phantoms, which closely imitate optical characteristics of real tissue. The system has modular construction and is based on the ISEL system, luminance and color meter and...
-
Raman spectroscopic investigation of blood and related materials
PublikacjaThis paper reports preliminary studies on use of Raman spectroscopy for investigation of blood. High quality blood spectra were recorded in-vitro with excitation wavelengths of 830 nm. Because of complex composition of the blood as well as by light attenuation and scattering in the tissues, spectra set up from wide, low-intensive Raman bands and intensive optical background. To get information about origin of bands in Raman spectra...
-
Gold nanoparticles and their coatings, their effect on cells and their interaction with radiation
PublikacjaTwo nanometre gold nanoparticles (AuNPs), bearing sugar moieties and/or polyethylene glycolamine (PEG-amine), were synthesised and evaluated for their in vitro toxicity and ability to radiosensitise cells with 220 kV and 6 MV X-rays, using four cell lines representing normal and cancerous skin and breast tissues. In addition to the observed intrinsic cancer-selective chemotoxicity, these AuNPs acted as radiosensitisers in combination with...
-
Porous Phantoms Mimicking Tissues – Investigation of Optical Parameter Stability Over Time
PublikacjaIn terms of optical parameters, optical phantoms can now replace live tissues and be used to validate optical measurement methods. Therefore, whether these parameters would be maintained after storage for 6 months was examined. The absorption and scattering coefficients were obtained from the measured transmittance and reflectance measurements taken 6 months apart and then compared. All of the measurements were conducted using...
-
Molecularly targeted nanoparticles: an emerging tool for evaluation of expression of the receptor for advanced glycation end products in a murine model of peripheral artery disease
PublikacjaAbstract Background: Molecular imaging with molecularly targeted probes is a powerful tool for studying the spatio-temporal interactions between complex biological processes. The pivotal role of the receptor for advanced glycation end products (RAGE) in numerous pathological processes, aroused the demand for RAGE targeted imaging in various diseases. In the study, we evaluated the use of a diagnostic imaging agent for RAGE quantification...
-
O07 Filaggrin insufficiency renders keratinocyte-derived small extracellular vesicles capable of affecting CD1a-mediated T-cell responses and promoting allergic inflammation
PublikacjaThe association between FLG loss-of-function mutations and the development of atopic dermatitis (AD) indicates that filaggrin is critical to skin barrier function; the mutations are also linked to additional allergic manifestations, but it is unknown how the skin may influence inflammation in distant tissues. Here we investigated the impact of filaggrin insufficiency on keratinocyte-derived exosome-enriched small extracellular...
-
Development and validation of lumbar spine finite element model
PublikacjaThe functional biomechanics of the lumbar spine have been better understood by finite element method (FEM) simulations. However, there are still areas where the behavior of soft tissues can be better modeled or described in a different way. The purpose of this research is to develop and validate a lumbar spine section intended for biomechanical research. A FE model of the 50th percentile adult male (AM) Total Human Model for Safety...
-
Chitosan-based inks for 3D printing and bioprinting
PublikacjaThe advent of 3D-printing/additive manufacturing in biomedical engineering field has introduced great potential for the preparation of 3D structures that can mimic native tissues. This technology has accelerated the progress in numerous areas of regenerative medicine, especially led to a big wave of biomimetic functional scaffold developments for tissue engineering demands. In recent years, the introduction of smart bio-inks has...
-
A review of methods of blood supply to organs of the gastrointestinal tract. State of art
PublikacjaThe correct assessment of blood supply is essential to eliminate possible postoperative complications. Re-anastomosis of the gastrointestinal tract after its resection must be preceded by the analysis of blood supply to the anastomosed fragments. It is important that the blood supply assessment procedure is reliable but also non-absorbing and, if possible, short. It should also be possible to repeat the procedure due to the need...
-
T1 RELAXATION TIME CALLIBRATION IN MAGNETIC RESONANCE IMAGING USING NANODIAMOND PHANTOMS
PublikacjaMRI is increasingly used in radiation treatment planning because of the excellent soft tissue contrast in the obtained images. It allows more precise definition of the boundaries between healthy tissues and those affected by cancerous lesions. To obtain good image quality, the difference in signal between two types of tissue must be significant despite the noise so it must be properly calibrated. This calibration includes...
-
The Use of Vegetables in the Biomonitoring of Cadmium and Lead Pollution in the Environment
PublikacjaLead and cadmium emitted from various anthropogenic sources have the ability to accumulate in tissues of living organisms. The phenomenon of accumulation of metals in the body is harmful and undesirable. On the other hand, the ability of plants to accumulate heavy metals from the individual elements of the environment has been used in biomonitoring of pollution. Leaf and root of vegetables have particular predisposition for accumulating...
-
A Measurement System for Quasi-Spectral Determination of Absorption and Scattering Parameters of Veterinary Tissue Phantoms
PublikacjaThis paper describes the construction of a system for the quasi-spectral determination of absorption and scattering parameters of animal tissue phantoms. Several tissue phantoms, including one reference and two modified for examination, were prepared from polydimethylsiloxane (PDMS). The phantoms were measured using a system based on an integrating sphere and the light sources of wavelengths commonly used for the treatment of various...
-
Relationship between heart rate variability, blood pressure and arterial wall properties during air and oxygen breathing in healthy subjects
PublikacjaPrevious studies reported that normobaric hyperoxia influences heart rate, arterial pressure, cardiac output and systemic vascular resistance, but the mechanisms underlying these changes are still not fully understood. Several factors are considered including degeneration of endothelium-derived nitric oxide by reactive oxygen species, the impact of oxygen-free radicals on tissues and alterations of autonomic nervous system function....
-
Reactions on the surface of the implant under the influence of biofilm
PublikacjaThe contact of a biomaterial with the biological environment in in vitro and in vivo tests leads to the production of a particular ecosystem in which the active roles perform both, the material surface and the extracellular matrix protein forming a biofilm. Proteins affect cell and bacteria adhesion processes, biological activity of cells and activation of inflammatory response.The knowledge of the reaction mechanisms active on...
-
Integrating Statistical and Machine‐Learning Approach for Meta‐Analysis of Bisphenol A‐Exposure Datasets Reveals Effects on Mouse Gene Expression within Pathways of Apoptosis and Cell Survival
PublikacjaBisphenols are important environmental pollutants that are extensively studied due to different detrimental effects, while the molecular mechanisms behind these effects are less well understood. Like other environmental pollutants, bisphenols are being tested in various experimental models, creating large expression datasets found in open access storage. The meta‐analysis of such datasets is, however, very complicated for various...
-
Electrophoretically Deposited Chitosan/Eudragit E 100/AgNPs Composite Coatings on Titanium Substrate as a Silver Release System
PublikacjaDue to the possibility of bacterial infections occurring around peri-implant tissues, it is necessary to provide implant coatings that release antibacterial substances. The scientific goal of this paper was to produce by electrophoretic deposition (EPD) a smart, chitosan/Eudragit E 100/silver nanoparticles (chit/EE100/AgNPs) composite coating on the surface of titanium grade 2 using different deposition parameters, such as the...
-
Activation of endogenous regenerative potential in mammals using epigenetic inhibitor zebularine
PublikacjaIn this work, a nucleoside inhibitor of DNA methyltransferases, zebularine, was investigated as a wound healing and regeneration promoting agent. It was found that a high dose of intraperitoneally delivered zebularine improved punch wound closure in the ear pinna in mice. Both cytidine, a zebularine analogue, and uridine, a zebularine metabolite, did not promote ear pinna hole closure. The effect of zebularine on ear pinna healing...
-
Phenotypic consequences of LYS4 gene disruption in Candida albicans
PublikacjaA BLAST search of the Candida Genome Database with the Saccharomyces cerevisiae LYS4 sequence known to encode homoaconitase (HA) revealed ORFs 19.3846 and 19.11327. Both alleles of the LYS4 gene were sequentially disrupted in Candida albicans BWP17 cells using PCR-based methodology. The null lys4Δ mutant exhibited lysine auxotrophy in minimal medium but was able to grow in the presence of L-Lys and α-aminoadipate, an intermediate...
-
Influence of pulse waves on the transmission of near-infrared radiation in outer-head tissue layers.
PublikacjaIn this study, we investigate the effect of pulse waves on the transmission of near-infrared radiation in the outer tissue layers of the human head. This effect is important in using optical radiation to monitor brain conditions based on measuring the transmission changes in the near-infrared radiation between the source and the detector, placed on the surface of the scalp. This is because the signal related to the changes in the...
-
Determination of pharmaceuticals in fish: method optimization and occurrence in different species from Mediterranean rivers
PublikacjaThe multi-residue analytical method developed, based on accelerated solvent extraction, gel permeation chromatography purification and UPLC-MS/MS analysis allowed the simultaneous determination of 21 pharmaceuticals. Recoveries obtained for most of the target compounds were higher than 50%. The application of UPLC-MS/MS operating in the MRM mode, with two transitions monitored for each compound, provided good sensitivity and selectivity....
-
The role of epigenetics in regeneration
PublikacjaComplex changes in chromatin structure and at the transcriptional level occur from the creation of a single parental gamete throughout fertilization, embryo development and the life of an adult organism. Epigenetic changes, such as methylation and hydroxymethylation of DNA or histone methylation and acetylation, are an important part of these processes. Epigenetic regulation has an essential influence on gene expression level. DNA...
-
Full scattering profile of circular optical phantoms mimicking biological tissue
PublikacjaHuman tissue is one of the most complex optical media since it is turbid and nonhomogeneous. In our poster, we suggest a new type of skin phantom and an optical method for sensing physiological tissue condition, basing on the collection of the ejected light at all exit angles, to receive the full scattering profile. Conducted experiments were carried out on an unique set-up for noninvasive encircled measurement. Set-up consisted...
-
Monitoring of breast tissue thermo-ablation by means of impedance measurements
PublikacjaW pracy przedstawiono rozważania dotyczące monitorowania jakości termoablacji zmian nowotworowych w piersi przy pomocy pomiarów impedancyjnych. Pokazano prototypowe konstrukcje sond do termoablacji jak również zaprezentowano wyniki symulacji i pierwszych eksperymentów. A usefulness of a developed probe combining power delivery to ablated breast tumour and simultaneous impedance measurements is discussed in the paper. It consists...
-
Therapeutic biomaterials - application in neurology and cardiology
PublikacjaBiomaterials are of interest in most medical fields. It's hard to imagine life without them. And due to the ever-increasing demand, scientists are developing new materials. Diseases of the nervous and cardiovascular systems are still a big problem, which are associated with a limited ability to regenerate brain or heart tissues. Therefore, this review discusses the advancement in biomaterial engineering for the treatment of neurological...
-
Therapeutic biomaterials – application in neurology and cardiology
PublikacjaBiomaterials are of interest in most medical fields. It's hard to imagine life without them. And due to the ever-increasing demand, scientists are developing new materials. Diseases of the nervous and cardiovascular systems are still a big problem, which are associated with a limited ability to regenerate brain or heart tissues. Therefore, this review discusses the advancement in biomaterial engineering for the treatment of neurological...
-
Measurements of fundamental properties of homogeneous tissue phantoms
PublikacjaWe present the optical measurement techniques used in human skin phantom studies. Their accuracy and the sources of errors in microscopic parameters’ estimation of the produced phantoms are described. We have produced optical phantoms for the purpose of simulating human skin tissue at the wavelength of 930 nm. Optical coherence tomography was used to measure the thickness and surface roughness and to detect the internal inhomogeneities....
-
Bacterial cellulose in the field of wound healing and regenerative medicine of skin: recent trends and future prospectives
PublikacjaIn this overview, we focused on the bacterial cellulose (BC) applications, described in recently published scientific papers, in the field of skin regenerative medicine and wound care industry. Bacterial cellulose was proven to be biocompatible with living tissues. Moreover, its mechanical properties and porous structure are considered to be suitable for biomedical applications. It is due to the fact that porous structure of bacterial...
-
The use of a one-step PCR method for the identification of Microsporum canis and Trichophyton mentagrophytes infection of pets
PublikacjaIntroduction: Dermatophytes are a closely related group of keratinophilic fungi. They encompass important etiological agents of superficial fungal infections. These fungi are able to invade keratinized tissues of humans and animals, causing dermatophytosis (ringworm) of hair, nails or skin. The aim: Traditional diagnostics of ringworm is based on morphological identification of cultured fungi and is time-consuming. Materials and methods:...
-
Comparative review of piezoelectric biomaterials approach for bone tissue engineering
PublikacjaBone as a minerals’ reservoir and rigid tissue of the body generating red and white blood cells supports various organs. Although the self-regeneration property of bone, it cannot regenerate spontaneously in severe damages and still remains as a challenging issue. Tissue engineering offers several techniques for regenerating damaged bones, where various biomaterials are examined to fabricate scaffolds for bone repair. Piezoelectric...
-
When Biobanks Meet Religion: Association Between Religiosity and Attitudes of Polish Medical Students Toward Biobanking of Human Biological Material for Research Purposes
PublikacjaWhile biobanking is expanding globally, the empirical evidence concerning the impact of religion on future healthcare professionals’ awareness and willingness to donate biospecimens for biobank research is lacking. To understand how medicalstudents’ religious beliefs can fuel their questions regarding how biospecimens would be stored, cared for, and used, we conducted a survey among 1500 medical students at Poznań University...
-
INFLUENCE OF PRESERVATIVE ON THE TENSILE STRENGTH OF THE TISSUE OF PORCINE CIRCULATORY SYSTEM
PublikacjaCurrently one of the leading causes of death worldwide is heart diseases which include calcification of heart valves and vascular aneurysm. There are many biomaterials that can substitute pathologically altered tissue, however, none of them is as perfect as native tissue. Currently, scientists are looking for new biomaterials that can be successfully implanted without exposing the patient to reoperation. Each material introduced...
-
Cancer-selective, single agent chemoradiosensitising gold nanoparticles
PublikacjaTwo nanometre gold nanoparticles (AuNPs), bearing sugar moieties and/or thiol-polyethylene glycol-amine (PEG-amine), were synthesised and evaluated for their in vitro toxicity and ability to radiosensitise cells with 220 kV and 6 MV X-rays, using four cell lines representing normal and cancerous skin and breast tissues. Acute 3 h exposure of cells to AuNPs, bearing PEG-amine only or a 50:50 ratio of alpha-galactose derivative and...
-
Development of potential candidate reference materials for drugs in bottom sediment, cod and herring tissues
PublikacjaRegular use of a reference material and participation in a proficiency testing program can improve the reliability of analytical data. This paper presents the preparation of candidate reference materials for the drugs metoprolol, propranolol, carbamazepine, naproxen, and acenocoumarol in freshwater bottom sediment and cod and herring tissues. These reference materials are not available commercially. Drugs (between 7 ng/g and 32...
-
Magnetic Field Generated by Short Circuit Current in the 110 kV Power System
PublikacjaElectric fields within tissues induced by magnetic fields including transients or short-term peaks should not be time averaged and be regarded as instantaneous values as established in the ICNIRP (International Commission on Non - Ionizing Radiation Protection) guidelines. Measurements of power lines magnetic fields with regard to human beings exposure are carried out typically with maximum current load at current balance condition...
-
Mechanical behaviour of the implant used in human hernia repair under physiological loads
PublikacjaIn laparoscopic operations of abdominal hernias some recurrences still take place, even when applying a surgical mesh. This is usually caused by a failure of the connection between the tissue and the implant. The study deals with the influence of an implant’s orientation on forces in joints, which connect the mesh to human tissues. In the paper, the implant is modelled as a membrane structure within framework of the Finite Element...
-
Multimodal analysis of traction forces and the temperature dynamics of living cells with a diamond-embedded substrate
PublikacjaCells and tissues are constantly exposed to chemical and physical signals that regulate physiological and pathological processes. This study explores the integration of two biophysical methods: traction force microscopy (TFM) and optically detected magnetic resonance (ODMR) to concurrently assess cellular traction forces and the local relative temperature. We present a novel elastic substrate with embedded nitrogen-vacancy microdiamonds...
-
The characterization of collagen‑based scaffolds modified with phenolic acids for tissue engineering application
PublikacjaThe aim of the experiment was to study the morphology of collagen-based scaffolds modified by caffeic acid, ferulic acid, and gallic acid, their swelling, and degradation rate, as well as the biological properties of scaffolds, such as antioxidant activity, hemo- and cytocompatibility, histological observation, and antibacterial properties. Scaffolds based on collagen with phenolic acid showed higher swelling rate and enzymatic...
-
Poloxamer: A versatile tri-block copolymer for biomedical applications
PublikacjaPoloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). Some chemical characteristics of poloxamers such as temperature-dependent self-assembly and thermo-reversible behavior along with biocompatibility and physiochemical properties make poloxamer-based biomaterials...
-
Consequences of lysine auxotrophy for Candida albicans adherence and biofilm formation
PublikacjaA number of factors are known to be involved in Candida albicans virulence, although biofilm development on the surfaces of indwelling medical devices is considered to promote superficial or systemic disease. Based on previously reported up-regulation of saccharopine and acetyllysine in biofilm cells and activation of the lysine biosynthesis/degradation pathway, we investigated...
-
Sequence variants of p21 gene of the MRL/MpJ mouse: a possible association with the deficit of p21 protein and regenerative phenotype.
PublikacjaThe MRL/MpJ mouse is known for its enhanced regeneration abilities that manifested themselves by scarless ear-hole wound closure. The deficit of p21 found in the MRL is associated with the regenerative capacity as the p21 gene knockout in a mouse strain unrelated to the MRL mouse results in an ear-hole closure effect, similar to that observed in the MRL mouse. Cdkn1a gene encodes p21 protein, a cyclin-dependent kinase inhibitor,...
-
A review: Fabrication of porous polyurethane scaffolds
PublikacjaThe aim of tissue engineering is the fabrication of three-dimensional scaffolds that can be used for the reconstruction and regeneration of damaged or deformed tissues and organs. A wide variety of techniques have been developed to create either fibrous or porous scaffolds from polymers, metals, composite materials and ceramics. However, the most promising materials are biodegradable polymers due to their comprehensive mechanical...
-
IR-THERMAL IMAGING IN CARDIOSURGERY
PublikacjaA method for monitoring the state of the myocardium during cardiosurgical interventions based on thermal IR imaging is presented. These methods called Static Thermography and Active Dynamic Thermography (ADT) uses information about distribution of temperature on the surface and an external excitation source to induce thermal transient processes in a tested object. Recording time series of thermograms allows to calculate parametric...
-
Chemical composition of shells from red (Strongylocentrotus franciscanum) and green (Strongylocentrotus droeba-chiensis) sea urchin
PublikacjaThe shells from red and green sea urchins accounted for 47.9 and 40.7% of their body weights, respectively. The red and green sea urchin shells contained 91.08 and 90.77% minerals and 4.06 and 4.99% proteins, respectively. The shells did not contain any chitin. Sea urchin shells had a relatively large amount of naphthoquinone pigments, 121 mg per 100 g in red and 163 mg per 100 g in green species. The small quantities of glucosamine...
-
A new diagnostic IR-thermal imaging method for evaluation of cardiosurgery procedures
PublikacjaTwo methods for monitoring the state of the myocardium during cardiosurgical interventions based on thermal IR imaging are presented below. These methods, called static thermography and active dynamic thermography (ADT), use information about the distribution of temperature on the surface, and an external excitation source to induce thermal transient processes in a tested object. Recording the time series of thermograms allows...
-
l-ascorbic acid modified poly(ester urethane)s as a suitable candidates for soft tissue engineering applications
PublikacjaIn this paper we created novel poly(ester urethane)s (PESUs) designed specifically for tissue engineering. The PESUs were derived from oligomeric α,ω-dihydroxy(ethylene-butylene adipate) (dHEBA), 1,4-butanediol (BDO) and aliphatic 1,6-hexamethylene diisocyanate (HDI) and modified with l-ascorbic acid to improve their biocompatibility. In addition, we determined their mechanical properties (such as tensile strength, elongation at...
-
Chitosan-protein scaffolds loaded with lysostaphin as potential antistaphylococcal wound dressing materials.
PublikacjaAIMS: The development of technology for preparing chitosan-protein scaffolds loaded with lysostaphin, which potentially could be used as dressing for wound treatment and soft tissue infections caused by Staphylococcus aureus. METHODS AND RESULTS: The unique technology of chitosan solubilization using gaseous CO(2) instead of organic or inorganic acids was used for the incorporation of lysostaphin, the enzyme that exhibits bactericidal...
-
Influence of electric, magnetic and electromagnetic fields on the circadian system – current stage of knowledge
PublikacjaOne of the side effects of each electrical device work is the electromagnetic field generated near its workplace. All organisms, including humans, are exposed daily to the influence of different types of this field, characterized by various physical parameters. Therefore, it is important to accurately determine the effects of an electromagnetic field on the physiological and pathological processes occurring in cells, tissues and...
-
SIMULATION OF PROCEED® SURGICAL MESH APPLIED TO VENTRAL HERNIA REPAIR
PublikacjaIn the present research, Proceed® implant is considered. The system is subjected to short-time dynamic pressure load, similar to post-operative cough naturally occurring in human abdomen. The model refers to a clinical case of 5cm of hernia operated by Proceed implant fixed by 15 joints every 3cm around the orifice. The simulations of the implanted mesh are performed by means of the Finite Element Method. The implant is modelled...