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12 Uppsatser om Coagulation - Sida 1 av 1

Blood compatibility of biomaterials made of recombinant spider silk

Native spider silk is an attractive lightweight natural polymeric material with a unique combination of strength, extendibility and flexibility. Synthetic, recombinant spider silk is an attractive biomaterial with several possible fields of application. When a foreign material is introduced to blood, this can for example cause unwanted Coagulation and complement activation. The aim of this study was to investigate if coatings of heparin or albumin could improve the blood compatibility of films of recombinant spider silk and to develop an initial method to do so. Hypothetically, objects like pacemakers, stents and dental implants could be covered with spider silk films of high blood compatibility to reduce potentially harmful foreign body reactions caused by the immune defense. Increased blood compatibility would likely lead to improvements for both the individual patients and the society thanks to reduced load on healthcare institutions. Our objective was to assess the blood compatibility of both functionalized and non-functionalized recombinant spider silk by evaluating Coagulation and activation of the complement system of the immune defense. Coagulation was evaluated visually on glass slides and complement activation was analyzed by measuring the concentration of the complement system mediator C3a in blood samples that had been exposed to the different materials. This study introduces a non-toxic and easy performed method of improving the blood compatibility of recombinant spider silk films by adding a heparin coating. Heparin coated surfaces had statistically significantly higher blood compatibility than uncoated surfaces. The effects of albumin coating of films were less clear compared to the results of heparin coated films. Complement activation could not be evaluated because of high activation in all samples prior contact with the materials that were included in the study..

Investigation of tissue factor mRNA levels in human platelets using real-time PCR

Tissue factor (TF), a 47 kDa glycoprotein, is the initiator of the extrinsic pathway of blood Coagulation and consequently of the upmost importance when damage to blood vessel occurs. The source of TF in circulation has been investigated. However, the source of TF is still not clear. One theory is that platelets express and increases the expression of TF after stimulation and the aim of our report was to investigate whether platelets really are a source for TF in circulation.Using specific primers for TF mRNA, platelets in plasma from healthy volunteers and from patients suffering from cardiac infarction were analyzed by using real-time polymerase chain reaction (PCR). Gel electrophoresis was performed after amplification of TF mRNA to verify the results.The samples were negative for TF when using real-time PCR and the few positive all had cycle threshold (Ct) values above 35.

Blödningsbenägenhet hos bengalkatter :

During the years 2005-2007 several cases of abnormal bleeding were seen after surgery in Bengal cats on veterinary clinics and animal hospitals in Sweden. In this study we have examined if the observed bleedings are due to an inherited defect of the Coagulation cascade. Ten Bengal cats were tested for activated partial thromboplastin time (P-APT-time) and one-stage protrombin time (P-PK), and nine of these cats were tested for fibrinogen quantity (P-fibrinogen). Four of the tested cats had shown signs of an abnormal bleeding after surgery, and five of the cats were genetically related to these cats. One cat had a small bleeding wound at the internal base of the right auricle.

Utvärdering av en snabbtest för diagnostisering av hypokalcemi hos nötkreatur :

Clinical signs of hypocalcaemia in dairy cows are easily recognized, and a rapid response to treatment generally confirms the diagnosis in the field. However, clinical signs of other disorders in cows, such as toxemia, calving paralysis, or muscoskeletal injury, may mimic those associated with hypocalcaemia. Therefore, making a diagnosis of hypocalcaemia on the basis of clinical signs alone may be difficult. In ambulatory veterinary practices, cow-side tests are useful to make the diagnosis and prognosis easier. Kruuse?s Kalcium Test is a cow-side test based on the principle that calcium ions are necessary for Coagulation of blood, and that chelation with EDTA prevent Coagulation.

Utveckling och validering av en LC-MS/MS metod för kvantifiering av clopidogrel och dess metabolit i plasma

Clopidogrel is an antiplatelet substance that prevents blood Coagulation in the arteries. It is an inactive pro drug that becomes activated after first-pass metabolism by the liver. The active metabolite of clopidogrel is 2-oxoclopidogrel, which is unstable therefore pharmacokinetic data is obtained by measuring the inactive metabolite clopidogrel acid in plasma. Clopidogrel is taken orally in tablet form. The aim of this project was to develop a LC-MS/MS method for quantification of clopidogrel and its metabolite in plasma. The method has been developed by optimizing the sample preparation.

Optimering av den kemiska reningen vid Fläskebo deponi

Landfill leachate contains a variety of contaminants and is created when rainwater percolates the landfill. For landfill management the leachate is the main issue that can cause problems to the environment. At the landfill of Fläskebo, Renova AB treats the leachate in a local treatment plant. The treatment consists of a chemical treatment step with chemical precipitation, flocculation, sedimentation and filtration, and a final step with a carbon and peat filter. Renova has to ensure that the condition of the leachate reaches the regulation set for the landfill before it is released to the recipient.

The impact of platelet storage time on transfusion results

Platelets are small fragments, but they are of crucial importance for the Coagulation. The risk of spontaneous bleeding increases when the level of platelets falls below a thrombocyte particle concentration threshold value of 50 x 109/L. In those cases a platelet transfusion might be compulsory. Ongoing research tries to improve the quality of the platelets and to increase the safety of the method used. However, we still need to better understand which factors that affect how patients react upon platelet transfusion.

Dexametasons effekt på trombocytaggregering och syreradikalproduktion

Platelets are important for the healing of damaged blood vessels since they have an importantpart to play in the Coagulation process. At the same time, the blood must be kept fluid and notcoagulate at the wrong time. Therefore there are factors that effect the aggregation of plateletsin a positive or a negative way.Previous investigations have shown that platelets during stirring conditions produce reactiveoxygen species (ROS) that weaken the inhibiting effect of nitric oxides (NO) on platelets andthat the drug Dexamethasone (Dex) can reduce the ROS-production.The aim of this project was to investigate if glucocorticoids, in this case Dexamethasone,could restore the inhibiting effect of NO on platelets and if there was any decrease in ROS-production.The result of the ROS-measurements showed a great variance and it was difficult to draw anyconclusions from them, but a clear decrease in ROS, as previous reported, was not shown. In the aggregation experiments the inhibiting effect of NO was observed through the drug S-nitroso-N-acetylpenicillamine (SNAP), a NO-donator.From the aggregation experiments, the result seemed to be that SNAP during longerincubation time lost its inhibiting effect, probably because the cells become desensitized.With superoxid dismutase (SOD), the effect of SNAP increased, both in the experiment withlonger and shorter incubation times. Dex seemed to reinforce the aggregation in relation toboth SOD and SNAP.

Magomvridning hos hund : akutsjukvård och postoperativ intensivvård

The aim of this literature study was to give a clear picture of what gastric dilatation-volvulus is, and how the acute- and postoperative treatment and care is managed. The general aim is to support and help the veterinary technicians in their clinical work. Gastric dilatation volvulus is always an emergency. The primarily goal when these dogs are hospitalized is to establish an adequate cardiovascular function. This is done by immediate intravenous fluid therapy followed by decompression of the dilated stomach.

Sample cradle prevents pre-analytic error on platelet counts but is not essential for hemoglobin measurement and prothrombin time

Introduction: It is recommended to place all the vacuum tubes directly on a sample cradle after vein puncture to prevent analytic error. This recommendation is not always easy to follow because the samples are taken by different professionals under different situations.  The three most common analyses, platelets count, haemoglobin and prothrombin time were tested.  Therefore, it was interesting to compare results from the three most common analyses with or without sample cradle, to evaluate the influence of this step on the result. Methods: Three analyses were preformed, using blood from 50 different persons. Each person gave two vacuum tubes, each contained 4.5mL of venous blood for the study.

Uran i dricksvatten : litteraturstudie om reningsmetoder samt pilotförsök med jonbytesteknik

Uranium (U) is a naturally occurring component in bedrock and under the "right" conditions it can dissolve and move into the ground water. Since many people in Sweden depend on drilled wells as their main drinking water supply, they may be exposed to the uranium in the water. Radioactive radiation is not the major concern associated with naturally occurring uranium. It is rather the chemical properties of uranium that make it a potential danger to human health. Uranium is proven to have toxic effects with respect to the functioning of the kidneys.

Toxiska ämnen för hund : råttgift och etylenglykol

Denna litteraturstudie behandlar förgiftningar hos hund med begränsning till förgiftning orsakat av etylenglykol och råttgift. Vilket av dessa ämnen som är farligast och hur stor risken är att en hund får i sig dem är två frågor som kommer att undersökas. Det kommer att tas reda på mer om hur det ligger till med etylenglykolets påstått söta smak. Syftet med studien är även att utreda om allmänhetens medvetenhet behöver ökas om vanliga potentiellt farliga ämnen för våra husdjur. Att hundar utsätts för förgiftningar är inte ovanligt och antalet försäkringsfall där hundar blivit förgiftade har ökat mellan 2010 och 2014. Om en hund utsätts för ett giftigt ämne är det mest optimala att så tidigt som möjligt hindra giftet från att absorberas från gastrointestinalkanalen och därmed hindra att det gör någon skada.