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Avaliação da qualidade in vitro do concentrado de hemácias felino colhido e armazenado em sistema manufaturado / Evaluation of the in vitro quality of the feline packed red blood cells collected and stored in manufactured systemLilian Sayuri Tatibana Fujimura 26 February 2013 (has links)
Esse estudo teve por objetivo avaliar a viabilidade e qualidade in vitro do concentrado de hemácias felino (CHF), colhido e armazenado em bolsas e produtos nacionais, remanufaturadas, pelo Laboratório de Hemoterapia do Serviço de Anestesia da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo, de acordo com normas definidas por órgãos regulamentadores como a ANVISA. Foram analisados parâmetros bioquímicos e hematológicos de 24 unidades de CHF nos dias 0, 14 e 21 de armazenamento. Utilizou-se sistema fechado para colheita e armazenamento do sangue com solução de anticoagulante-preservativa CPDA-1. A avaliação consistiu na mensuração de porcentagem de hematócrito, hemoglobina total, hemoglobina extracelular, porcentagem de hemólise, concentrações de potássio, lactato, glicose, ATP, pH, bicarbonato, pressão de CO2 e O2, inspeção visual da bolsa e cultura microbiológica aeróbia e anaeróbia. Os resultados obtidos foram avaliados estatisticamente por meio de testes paramétricos, sendo que as determinações de hematócrito, hemoglobina total não apresentaram variação significante nos 21 dias de preservação, enquanto os de potássio, lactato, pO2 aumentaram gradativamente de forma significante. Os níveis de ATP, glicose, pH, bicarbonato e pCO2 reduziram de forma significante com o decorrer do tempo. Não houve alteração à inspeção visual das bolsas de sangue, nem crescimento de microorganismos nas culturas realizadas. Por meio destas avaliações constatouse que o sistema remanufaturado com produtos nacionais pode ser empregado com segurança para obtenção de sangue felino tendo-se em vista que se manteve estéril, com eficiente conservação do concentrado de hemácias felino em CPDA-1 até o 21º dia de armazenamento. / This study aimed to evaluate the feasibility and quality of in vitro feline packed red blood cells (CHF), harvested and stored in bags and domestic products, manufactured, Hematology Laboratory at the Department of Anesthesia, Faculty of Veterinary Medicine, University of São Paulo, according to standards set by regulatory bodies such as ANVISA. Were analyzed biochemical and hematological parameters 24 units of CHF on days 0, 14 and 21 of storage. We used a closed system for collection and storage of blood with preservative-anticoagulant solution CPDA-1. The evaluation consisted in measuring percentage of hematocrit, total hemoglobin, extracellular hemoglobin, percentage of hemolysis, potassium concentrations, lactate, glucose, ATP, pH, bicarbonate, CO2 and O2 pressure, visual inspection of the bag and aerobic and anaerobic microbiological culture . The results were statistically analyzed using parametric tests, and determinations of hematocrit, total hemoglobin showed no significant variation within 21 days of preservation, while potassium lactate, pO2 gradually increased significantly. ATP levels, glucose, pH, pCO2 and bicarbonate decreased significantly with time. There was no change to the visual inspection of blood bags, or growth of microorganisms in the cultures performed. Through these evaluations it was found that the system refilled with domestic products can be used safely for obtaining blood feline bearing in mind that remained sterile, efficient storage of red blood cells feline in CPDA-1 until the 21 th days of storage.
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The Rational Design of Potent Ice Recrystallization Inhibitors for Use as Novel CryoprotectantsCapicciotti, Chantelle January 2014 (has links)
The development of effective methods to cryopreserve precious cell types has had tremendous impact on regenerative and transfusion medicine. Hematopoietic stem cell (HSC) transplants from cryopreserved umbilical cord blood (UCB) have been used for regenerative medicine therapies to treat conditions including hematological cancers and immodeficiencies. Red blood cell (RBC) cryopreservation in blood banks extends RBC storage time from 42 days (for
hypothermic storage) to 10 years and can overcome shortages in blood supplies from the high demand of RBC transfusions. Currently, the most commonly utilized cryoprotectants are 10%
dimethyl sulfoxide (DMSO) for UCB and 40% glycerol for RBCs. DMSO is significantly toxic
both to cells and patients upon its infusion. Glycerol must be removed to <1% post-thaw using
complicated, time consuming and expensive deglycerolization procedures prior to transfusion to prevent intravascular hemolysis. Thus, there is an urgent need for improvements in
cryopreservation processes to reduce/eliminate the use of DMSO and glycerol.
Ice recrystallization during cryopreservation is a significant contributor to cellular injury and
reduced cell viability. Compounds capable of inhibiting this process are thus highly desirable as novel cryoprotectants to mitigate this damage. The first compounds discovered that were ice recrystallization inhibitors were the biological antifreezes (BAs), consisting of antifreeze proteins and glycoproteins (AFPs and AFGPs). As such, BAs have been explored as potential cryoprotectants, however this has been met with limited success. The thermal hysteresis (TH)activity and ice binding capabilities associated with these compounds can facilitate cellular damage, especially at the temperatures associated with cryopreservation. Consequently,
compounds that possess “custom-tailored” antifreeze activity, meaning they exhibit the potent ice recrystallization inhibition (IRI) activity without the ability to bind to ice or exhibit TH activity,are highly desirable for potential use in cryopreservation.
This thesis focuses on the rational design of potent ice recrystallization inhibitors and on
elucidating important key structural motifs that are essential for potent IRI activity. While
particular emphasis in on the development of small molecule IRIs, exploration into structural
features that influence the IRI of natural and synthetic BAs and BA analogues is also described as these are some of the most potent inhibitors known to date. Furthermore, this thesis also
investigates the use of small molecule IRIs for the cryopreservation of various different cell types to ascertain their potential as novel cryoprotectants to improve upon current cryopreservation protocols, in particular those used for the long-term storage of blood and blood products.
Through structure-function studies the influence of (glyco)peptide length, glycosylation and
solution structure for the IRI activity of synthetic AFGPs and their analogues is described. This thesis also explores the relationship between IRI, TH and cryopreservation ability of natural
AFGPs, AFPs and mutants of AFPs. While these results further demonstrated that BAs are
ineffective as cryoprotectants, it revealed the potential influence of ice crystal shape and growth progression on cell survival during cryopreservation.
One of the most significant results of this thesis is the discovery of alkyl- and phenolicglycosides as the first small molecule ice recrystallization inhibitors. Prior to this discovery, all reported small molecules exhibited only a weak to moderate ability to inhibit ice recrystallization.
To understand how these novel small molecules inhibit this process, structure-function studies
were conducted on highly IRI active molecules. These results indicated that key structural
features, including the configuration of carbons bearing hydroxyl groups and the configuration of
the anomeric center bearing the aglycone, are crucial for potent activity. Furthermore, studies on the phenolic-glycosides determined that the presence of specific substituents and their position on the aryl ring could result in potent activity. Moreover, these studies underscored the sensitivity of IRI activity to structural modifications as simply altering a single atom or functional group on this substituent could be detrimental for activity.
Finally, various IRI active small molecules were explored for their cryopreservation potential
with different cell types including a human liver cell line (HepG2), HSCs obtained from human
UCB, and RBCs obtained from human peripheral blood. A number of phenolic-glycosides were
found to be effective cryo-additives for RBC freezing with significantly reduced glycerol
concentrations (less than 15%). This is highly significant as it could drastically decrease the
deglycerolization processing times that are required when RBCs are cryopreserved with 40%
glycerol. Furthermore, it demonstrates the potential for IRI active small molecules as novel
cryoprotectants that can improve upon current cryopreservation protocols that are limited in terms of the commonly used cryoprotectants, DMSO and glycerol.
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Avaliação bioquímica in vitro do concentrado de eritrócitos felino Armazenado em soluções de cpda-1 e cpd/sagm durante 35 dias / Biochemistry changes of feline erythrocyte concentrates stored in cpda-1 and cpd-sagm during 35 daysSonaglio, Franciele January 2014 (has links)
O curto tempo de armazenamento dos hemocomponentes é um dos fatores que dificulta e limita a quantidade de sangue que pode ser efetivamente armazenada, o que é uma desvantagem na medicina veterinária, pois o acesso a doadores é restrito e a demanda é contínua e cada vez maior na prática de clínicas e hospitais veterinários. Durante o armazenamento do sangue em baixas temperaturas, seja sob a forma de sangue total ou concentrado de eritrócitos, há uma queda intensa de metabólitos importantes para a viabilidade e funcionalidade dos eritrócitos. O desenvolvimento de meios e soluções de preservação sanguínea possibilitou o armazenamento dos eritrócitos e, consequentemente, facilitou o trabalho dos bancos de sangue. Portanto, a busca por melhores formas e soluções para preservação capazes de evitar ou diminuir estes efeitos prejudiciais durante o seu armazenamento é contínua, para que ao final se obtenha uma melhor qualidade do sangue transfundido. O presente trabalho avaliou o concentrado de eritrócitos felino armazenado na solução de CPDA-1 e CPD/SAGM durante 35 dias. Os dados laboratoriais foram comparados entre grupos e ao longo do tempo. Neste experimento foram utilizadas 10 bolsas de concentrado de eritrócitos felino divididos em dois grupos de cinco para avaliação de cada um dos aditivos. Os parâmetros laboratoriais K+, Na+, Cl-, lactato, HCO3-, amônia, glicose e pH foram avaliados nos dias 1, 7, 14, 21, 28 e 35 após a coleta. Vários parâmetros (K+, lactato, HCO3, glicose e cloreto) demonstraram que a solução CPD/SAGM manteve o metabolismo energético do eritrócito mais estável. Com este trabalho, foi possível entender melhor as alterações metabólicas sofridas pelos eritrócitos felinos durante o armazenamento. Concluímos que, apesar da solução CPD/SAGM se mostrar mais eficaz in vitro, são necessários mais estudos com relação aos hemocomponentes em gatos e à sua viabilidade pós-transfusional. / The short shelf life of blood products is one factor that complicates and limits the amount of blood that can be effectively stored, and it is a disadvantage in veterinary practice, because the access to donors is restricted and the demand is continuous and increasing at veterinary clinics and hospitals. During blood storage at low temperatures, either as whole blood or as packed red cells, there is a significant decrease of metabolites that are important for the viability and functionality of erythrocytes. The development of blood preservation solutions has enabled the storage of red blood cells and improved the service at the blood banks. Therefore, the search for better ways and blood preservation solutions to avoid or reduce these harmful effects during the storage conditions is continuous, in order to obtain the best blood product to be transfused. This study evaluated 10 bags of feline erythrocyte concentrate divided into two groups, stored in CPDA-1 and CPD/SAGM solutions during 35 days. The laboratory data were compared between groups and over time. K+, Na+, Cl-, lactate, HCO3-, ammonia, glucose and pH were assessed on days 1, 7, 14, 21, 28, and 35 after collection. On various parameters (K+, Cl-, HCO3-, glucose and lactate) solution of CPD/SAGM kept the energy metabolism of red blood cells more stable. With these results we can better understand the biochemical changes of feline erythrocytes during storage. We conclude that, although the CPD/SAGM solution shown to be more effective, more studies are needed to improve knowledge of feline blood components and post-transfusion viability.
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A Raman Flow Cytometer: An Innovative Microfluidic Approach for Continuous Label-Free Analysis of Cells via Raman SpectroscopyDe Grazia, Antonio 05 May 2015 (has links)
In this work a Raman flow cytometer is presented.
It is a whole new microfluidic device that takes advantage of basic principles of Raman spectroscopy and fluorescent flow cytometry mixed together in a system of particularly shaped channels. These are indeed composed by specific shape and sizes – thanks to which cells can flow one-by-one – and a trap by means of which cells are trapped in order to perform Raman analysis on single ones in a constant and passive way. In this sense the microfluidic device promotes a fast method to look for single cells in a whole multicellular sample.
It is a label-free analysis and this means that, on the contrary of what happens with fluorescent flow cytometry, the sample does not need to undergo any particular time-consuming pretreatment before being analyzed. Moreover it gives a complete information about the biochemical content of the sample thanks to the involvement of Raman spectroscopy as method of analysis.
Many thought about a device like this, but eventually it is the first one being designed, fabricated and tested. The materials involved in the production of the Raman flow cytometer are chosen wisely. In particular the chip – the most important component of the device – is multilayered, being composed by a slide of calcium fluoride (which gives a negligible signal in Raman analyses), a photosensitive resist containing a pattern with channels and another slide of calcium fluoride in order for the channels to be sealed on both sides. The chip is, in turn, connected to gaskets and external frames. Several fabrication processes are followed to ultimately get the complete Raman flow cytometer and experiments on red blood cells demonstrate its validity in this field.
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Collective phenomena in blood suspensions / Phénomènes collectifs dans les suspensions sanguinesChachanidze, Revaz 27 November 2018 (has links)
Ce travail a été réalisé dans l’I. R. P. H. E. (Institut de Recherche sur les Phénomènes Hors Équilibre), unité de recherche de l’Université d’Aix-Marseille en collaboration avec l’Université de la Sarre, la Faculté de Physique Expérimentale. Cette étude est consacrée à une meilleure compréhension de la microcirculation du sang in vitro, ainsi que des phénomènes collectifs qui prennent place dans la microcirculation. Il se concentre principalement sur la margination en fonction du contrast de rigidité dans une suspension de globules rouges. L’expérience modale a été développée pour étudier la margination, causée exclusivement par le contraste de la déformabilité entre les deux sous-populations de globules rouges: les saines et les rigidifiées / This work was carried out in collaboration between I.R.P.H.E. (Institut de Recherche sur les Phénomènes Hors Équilibre), research unit of Aix-Marseille University and University of Saarland, Faculty of Experimental Physics (Naturwissenschaftlich-Technische Fakultät der Universität des Saarlandes) and aims to investigate microcirculatory hydrodynamics of blood in vitro. The study is dedicated to better understanding of complex collective phenomena that take place in microcirculation of blood through microfluidic in vitro experiments. It mainly focuses rigidity based margination in suspension of RBCs. For this purpose, model experiment was developed to examine margination caused exclusively by contrast of deformability between two sub-populations of RBCs
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Etické aspekty dárcovství krvetvorných buněk / Ethical aspects of stem cell donationBřezinová, Ludmila January 2013 (has links)
Donation of blood stem cells could help save the life of patients with a variety of hematological diseases. Despite its topicality it does not belong to widely known areas and a large section of the population deals with this issue only if it begins to relate to them personally. Therefore I would like to contribute with my work I would to the wider debate on this topic focusing on ethical issues. In the theoretical part I describe the history of the donation and transplantation of hematopoietic stem cells, which together are inseparable. I introduce the role of the Czech Stem Cells Donor Registry and the legislative definition of its functioning. For a comprehensive look at this issue I describe the methods of blood stem cells collection and their transplantation primarily to depict the practical issues and questions donors and patients are exposed to. The main part of my work is devoted to the ethically problematic areas which we as the registry staff can meet and whose solution we are exposed to. The research part of my work is focused on the donor perception of the need to be informed and devoted to the fate and identity of the stem cells recipient in the context of the entire donation process. The objective is to find the right approach to donors who selflessly undergo the process of donation....
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Determination of the acousto-mechanical properties of chitosan and age dependent characteristics of red blood cells by confocal scanning acoustic microscopy with vector contrastAhmed Mohamed, Esam Eldin 22 November 2012 (has links)
The acoustic microscope is an efficient non-invasive tool that can explore the acoustic properties and the related mechanical microstructure of a wide diversity of materials, including biomedical and biological samples, which are, nowadays, among the most intriguing targets for investigations. In the presented work, an acoustic microscope with vector contrast is used to image and characterize the acousto-mechanical properties of chitosan, an abundant natural derivative of chitin known to be a biodegradable, nontoxic and versatile biopolymer that suits many biomedical applications such as its usage in tissue engineering. The work also presents key measurements for the study of the acousto-mechanical properties that are subject to variations during the life span of red blood cells (RBCs). The characteristic signature of fixed cells from groups of three different ages, fractionated according to mass density, is obtained from the acoustic microscope images. The analysis of these data enabled the quantitative comparisons between the acousto-mechanical properties (velocity and attenuation of ultrasound propagating in the cells, mass density, and bulk modulus of compression). Comparison of the contrasts in the acoustic micrographs for the cells of the different age groups is exploited to generate a model that determines the age of the individual cells in a sample of red blood cells collected from a healthy person. The dependence of the parameters of the cells including density, velocity and attenuation of longitudinal polarized ultrasonic waves travelling in the cells on the age of the cell is also presented. The output signal in dependence on the thickness of the sample, the so called V(d), represented as polar graph was exploited as the method of analysis of the data extracted from the acoustic micrographs imaged with ultrasound of a center frequency of 1.2 GHz. This procedure allows for the extraction of the quantitative information from a single image in magnitude and phase contrast and allows for height profiling with so called super resolution, relating to resolution below the diffraction limit, based on the developed modeling, beside of other advantages concerning the acoustic characterization of biomedical and biological samples. This method and the applications are presented and discussed together with the developed or adapted modeling.
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Effects of dehydration on hemoglobin oxygen affinity and blood cell volume in two anuransZygmunt, Andrew Christopher 01 January 1984 (has links)
Two aspects of possible adaptation In cardiovascular performance caused by Increased plasma electrolytes were examined. Cells In anisotonic plasma may either act as osmometers or volume regulate. Blood flow rate Is dependent upon cell viscosity, which in turn is a consequence of cell volume and membrane deform-ability. Cell volume changes which Increase membrane deform-ability will thus potentially extend the limits of dehydration tolerance. It was found in R. catesbeiana and B. marinus that red blood cell Is maintain constant volume during dehydration. Cells in vitro Initially lose water, but then sodium, potassium and water move Into the cell. Cell viscosity within the physiologic range of hematocrits was higher In salt loaded non-regulating cell Is of B. marinus than In regulating isotonic cells.
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Measurement of Red Blood Cell Oxygenation State by MagnetophoresisSmith, Nina A. 19 September 2019 (has links)
No description available.
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The study of animal cells through combination of numerical analysis and variousmagnetic microfluidics systems.Kim, James 22 September 2020 (has links)
No description available.
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