975 resultados para quick coagulation


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OBJECTIVE: To assess hematological and biochemical features of splenic effluent blood and their influence on the rise of hematological values after splenectomy.METHODS: we studied 20 patients undergoing surgical treatment for schistosomatic portal hypertension. We collected blood samples for CBC, coagulation, bilirubin and albumin in the splenic vein (perioperative) and peripheral blood (immediately pre and postoperative periods).RESULTS: the splenic blood showed higher values of red blood cells, hemoglobin, hematocrit, platelet count, total leukocytes, neutrophils, lymphocytes, monocytes, eosinophils and basophils, as well as reduction of laboratory coagulation parameters in relation to peripheral blood collected preoperatively. In the postoperative peripheral blood there was an increase in the overall leukocytes and in their neutrophil component, and decreased levels of basophils, eosinophils and lymphocytes. The other postoperative variables of complete blood count and coagulation tests were not different compared with the splenic blood. The albumin values were lower postoperatively when compared to preoperative and splenic blood. There were higher values of direct bilirubin in the postoperative period when compared with the preoperative and splenic blood. Postoperative indirect bilirubin was lower compared to its value in the splenic blood.CONCLUSION: hematological and biochemical values of splenic effluent blood are higher than those found in peripheral blood in the presence of schistosomal splenomegaly. However, the splenic blood effluent is not sufficient to raise the blood levels found after splenectomy.

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The objective is to reinforce the importance of blood reinfusion as a cheap, safe and simple method, which can be used in small hospitals, especially those in which there is no blood bank. Moreover, even with the use of devices that perform the collection and filtration of blood, more recent studies show that the cost-benefit ratio is much better when autologous transfusion is compared with blood transfusions, even when there is injury to hollow viscera and blood contamination. It is known that the allogeneic blood transfusion carries a number of risks to patients, among them are the coagulation disorders mediated by excess enzymes in the conserved blood, and deficiency in clotting factors, mainly the Factor V, the proacelerin. Another factor would be the risk of contamination with still unknown pathogens or that are not investigated during screening for selection of donors, such as the West Nile Fever and Creutzfeldt-Jacob, better known as "Mad Cow" disease. Comparing both methods, we conclude that blood autotransfusion has numerous advantages over heterologous transfusion, even in large hospitals. We are not against blood transfusions, just do not agree that the patient's own blood is discarded without making sure there will be enough blood in stock to get him out of the hemorrhagic shock.

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Data is the most important asset of a company in the information age. Other assets, such as technology, facilities or products can be copied or reverse-engineered, employees can be brought over, but data remains unique to every company. As data management topics are slowly moving from unknown unknowns to known unknowns, tools to evaluate and manage data properly are developed and refined. Many projects are in progress today to develop various maturity models for evaluating information and data management practices. These maturity models come in many shapes and sizes: from short and concise ones meant for a quick assessment, to complex ones that call for an expert assessment by experienced consultants. In this paper several of them, made not only by external inter-organizational groups and authors, but also developed internally at a Major Energy Provider Company (MEPC) are juxtaposed and thoroughly analyzed. Apart from analyzing the available maturity models related to Data Management, this paper also selects the one with the most merit and describes and analyzes using it to perform a maturity assessment in MEPC. The utility of maturity models is two-fold: descriptive and prescriptive. Besides recording the current state of Data Management practices maturity by performing the assessments, this maturity model is also used to chart the way forward. Thus, after the current situation is presented, analysis and recommendations on how to improve it based on the definitions of higher levels of maturity are given. Generally, the main trend observed was the widening of the Data Management field to include more business and “soft” areas (as opposed to technical ones) and the change of focus towards business value of data, while assuming that the underlying IT systems for managing data are “ideal”, that is, left to the purely technical disciplines to design and maintain. This trend is not only present in Data Management but in other technological areas as well, where more and more attention is given to innovative use of technology, while acknowledging that the strategic importance of IT as such is diminishing.

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Tutkimuksen tavoitteena on konkreettisen yritysverkoston avulla selvittää, minkälaisia ovat ulkomaalaisen yrityksen potentiaaliset kumppanit ja yritysten väliset suhteet Venäjällä. Toisena tavoitteena on kuvata käytännön työelämään sopivalla menetelmällä riittävän kokonaisvaltaisesti yritysverkoston kumppanit sekä kumppaneiden ja kärkiyrityksen väliset suhteet. Samalla tarkastellaan yritysten välisten suhteiden riskejä. Selvitysmenetelmällä pyritään nopeuteen ja ketteryyteen ja sen tavoitteena on lisätä ulkomaisen johdon käsitystä yritysverkostosta johdon päätöksentekoa varten. Tutkimus jakaantuu teoria tarkasteluun ja yhden Venäjällä toimivan ulkomaisen yrityksen osto-osaston verkostoa selvittävään empiiriseen osaan. Teoriatarkastelussa selvitetään erilaisia lähestymistapoja ja laajempia viitekehyksiä yritysverkostojen tutkimukseen. Teoriatarkastelun perusteella valittiin viitekehykset yrityskumppaneiden ja yritysten välisen suhteen sekä riskien arviointiin. Empiirisen osan tutkimus toteutettiin haastattelukyselytutkimuksena perustuen näihin viitekehyksiin. Yrityskumppaneita ja yritysten välisiä suhteita tarkastellaan tilastollisin menetelmin ja riskejä arvioidaan laadullisella tutkimusotteella. Tutkimustulokset vastaavat monelta osin liiketoimintakulttuurista ja –ympäristöstä saatua kokemukseen ja tutkimustietoon perustuvaa käsitystä. Verkostoitumisen kulmakivet ovat hyvin toimivat ja määritellyt vaihdannan liiketoiminta- ja tukiprosessit, hyvin tunnetut kumppanit ja tälle perustalle rakennetut sosiaaliset suhteet sekä liiketoimintaympäristöön ja –kulttuuriin soveltuvat yhteistyökompetenssit. Tutkitun yritysverkoston yhteistyösuhteet voidaan jakaa hierarkkiseen organisaatiokumppanuuteen, toimittajakumppanuuteen, luottamukseen perustuvaan markkinaehtoiseen suhteeseen ja opportunistiseen markkinasuhteeseen. Hyviä yhteistyökumppaneita ja –suhteita löytyy taustaltaan erilaisista toimittajista. Tutkimuksessa käytetyt viitekehykset toimivat hyvin erityisesti yrityskumppanin arvioinnissa. Yritysten välisen suhteen arviointiin käytetyn viitekehyksen ongelmat liittyivät lähinnä erilaiseen liiketoimintakulttuuriin ja käsitykseen yritysten välisestä strategisesta suhteesta. Riskit liittyivät toimitussuhteeseen useammin kuin omaan organisaatioon tai toimittajaan.

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The objective of the study was to evaluate the topical effects of 0.2% Cyclosporine A (CsA) on corneal neovascularization of rats following surgical implantation of equine amniotic membrane into a corneal stroma micropocket. The implantation of xenologous amniotic membrane was performed bilaterally in 90 rats. In the same day of the surgery each right eye started receiving topical CsA twice a day. The left eye received no medication and served as a control. The evaluation of corneal neovascularization was performed by computerized image analysis and histopathological evaluation at 1, 3, 7, 15, 30 and 60 days postoperatively. For the image analysis 10 animals were used per time period, and for the histopathological examination, five animals were used per time period. Image analysis found that corneal neovascularization began on the 3rd postoperative day, reached its peak on the 7th day, and then progressively and rapidly decreased. Statistic analysis indicated that neovascularization of the CsA treated eye on the 7th day was significantly higher than that observed in untreated eyes. On the 30th day, however, this pattern was reversed with the neovascularization observed in the CsA treated eyes declining to the low levels observed on the 3rd day. The degree of neovascularization in the untreated eyes on the 30th day declined to the baseline levels found on day 3 at the 60th day. Histopathological analysis indicated that deposition of collagen in the implanted tissue was completed by the 15th day. Therefore, we concluded that (1) equine amniotic membrane in rat corneal stroma produced an intense neovascularization until the 15th day postoperatively and then regressed, (2) deposition of collagen of the implanted tissue was completed on the 15th day postoperatively, and (3) use of CsA was associated with increase in the corneal neovascularization initially, followed by a quick and intense regression.

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Technological capabilities are built to support different types of collaboration, and this gives the justification to widely observe, how activity environments are influenced by technology. Technology as an enabler can be addressed from different perspectives, other than merely technological. Dynamic, evolving environment is at the same time interesting but also challenging. As a multinational collaboration environment, the maritime surveillance is an good example of time critical and evolving environment, where technological solutions enable new ways of collaboration. Justification for the inspiration to use maritime environment as the baseline for understanding the challenges in creating and maintaining adequate level of situational awareness, derives from the complexity of the collaboration and information sharing environment elements, needed to be taken into account, when analyzing criticalities related to decision making. Situational awareness is an important element supporting decision making, and challenges related to it can also be observed in the maritime environment. This dissertation describes the structures and factors involved in this complex setting, found from the case studies that should be taken into account when trying to understand, how these elements affect the activities. This dissertation focuses on the gray area that is between a life threatening situation and normal everyday activities. From the multinational experimentation series case studies, MNE5 and MNE6 it was possible to observe situations that were not life threatening for the participants themselves, but not also basic every day activities. These case studies provided a unique possibility to see situations, where gaining of situational awareness and decision making are challenged with time critical crisis situations. Unfortunately organizations do not normally take the benefit from the everyday work to prepare themselves for possible emerging crisis situations. This dissertation focuses on creating a conceptual model and a concept that supports organizations – also outside the maritime community – to improve their ability to support gaining of situational awareness from the individual training level, all the way to changes in organizational structures in aiming for better support for decision making from the individual level to the highest decision making level. Quick changes and unpredictability are reality in organizations and organizations do not have the possibility to control all the factors that affect their functioning. Since we cannot be prepared for everything, and predict every crisis, individual activities inside teams and as a part of organizations, need to be supported with guidance, tools and training in order to support acting in challenging situations. In fact the ideology of the conceptual model created, lies especially in the aim of not controlling everything in beforehand, but supporting organizations with concrete procedures to help individuals to react in different, unpredictable situations, instead of focusing on traditional risk prevention and management. Technological capabilities are not automatically solutions for functional challenges; this is why it is justified to broaden the problem area observation from the technological perspective. This dissertation demonstrates that it is possible to support collaboration in a multinational environment with technological solutions, but it requires the recognition of technological limitations and accepting the possible restrictions related to technological innovations. Technology should not be considered value per se, the value of technology should be defined according to the support of activities, including strategic and operational environment evaluation, identification of organizational elements, and taking into account also the social factors and their challenges. Then we are one step closer to providing technological solutions that support the actual activities by taking into account the variables of the activity environment in question. The multidisciplinary view to approach the information sharing and collaboration framework, is derived especially from the complexity of decision making and building of situational awareness, since they are not build or created in vacuity, but in the organizational framework by the people doing it with the technological capabilities, enabled by the organizational structures. Introduced case studies were related to maritime environment, but according to the research results, it is valid to argue, that based on the lessons learned it is possible to create and further develop conceptual model and to create a general concept to support a wider range of organizations in their attempt to gain better level of situational awareness (SA) and to support decision making. To proof the versatile usage of the developed concept, I have introduced the case study findings to the health care environment and reflected the identified elements from the trauma center to the created concept. The main contribution to complete this adventure is the presented situational awareness concept created in the respect to NATO concept structure. This has been done to tackle the challenge of collaboration by focusing on situational awareness in the information sharing context by providing a theoretical ground and understanding, of how these issues should be approached, and how these elements can be generalized and used to support activities in other environments as well. This dissertation research has been a several year evolving process reflecting and affecting presented case studies and this learning experience from the case studies has also affected the goals and research questions of this dissertation. This venture has been written from a retro perspective according to ideology of process modeling and design rationale to present to the reader how this entire journey took place and what where the critical milestones that affected the end result, conceptual model. Support in a challenging information sharing framework can be provided with the right type of combination of tools, procedures and individual effort. This dissertation will provide insights to those with a new approach to war technology for the organizations to gain a better level of awareness and to improve the capabilities in decision making. This dissertation will present, from the war technology starting point, a new approach and possibility for the organizations to create a better level of awareness and support for decision making with the right combination of tools, procedures and individual effort.

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Five male 6-8 month-old Murrah buffalo calves were orally dosed with the fresh aerial parts of Baccharis megapotamica var. weirii at doses of 1, 3, 4, 5 and 10g/kg body weight (bw) (~1-10mg macrocyclic trichothecenes/kg/bw). The B. megapotamica used for the experiment was harvested on a farm where a recent spontaneous outbreak of poisoning caused by such plant had occurred. Clinical signs appeared 4-20 hours and 4 buffaloes died 18-49 hours after the ingestion of the plant. Clinical signs were apathy, anorexia, and watery diarrhea, fever, colic, drooling, muscle tremors, restlessness, laborious breathing and ruminal atony, and dehydration. The most consistent gross findings were restricted to the gastrointestinal (GI) tract consisted of varying degrees of edema and reddening of the mucosa of the forestomach. Histopathological findings consisted of varying degrees of necrosis of the epithelial lining of the forestomach and of lymphocytes within lymphoid organs and aggregates. Fibrin thrombi were consistently found in sub-mucosal vessels of the forestomach and in the lumen of hepatic sinusoids. It is suggested that dehydration, septicemia and disseminated intravascular coagulation participate in the pathogenesis of the intoxication and play a role as a cause of death. A subsample of B. megapotamica var. weirii was frozen-dried and ground and analyzed using UHPLC (Ultra High Performance Liquid Chromatography) with high resolution Time of Flight mass spectrometry and tandem mass spectrometry, it was shown that the plant material contained at least 51 different macrocyclic trichothecenes at a total level of 1.1-1.2mg/g. About 15-20% of the total trichothecenes contents was found to be monosaccharide conjugates, with two thirds of these being glucose conjugates and one third constituted by six aldopentose conjugates (probably xylose), which has never been reported in the literature.

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In the 21st century, agile project management (APM) has emerged as a major evolutionary step in the area of software project management. APM is defined as a conceptual framework, consisting of various methods such as Scrum, quick respond to change, better customer collaboration, minimum coverage of documentation and extreme programming (XP) that facilitates to produce working software in multiple iterations with team work. Because agile project management has become more popular in the software industry in recent years, it constitutes an interesting and comprehensive research topic. This thesis presents a systematic literature review (SLR) of published research articles concerning agile project management. Based on a predefined search strategy, 273 such articles were identified, of which 44 were included in the review. The selected 44 articles were published between years 2005 and 2012. The thesis defines a review process by developing a review protocol and presenting the results of the review. The results are expected to provide researchers, software man

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This study describes the epidemiological and pathological aspects of an outbreak of acute fasciolosis in cattle in southern Brazil. Fifteen out of 70 three-year-old pregnant cows lost weight in the 30-40 days prior to calving. Clinical signs included diarrhea, weakness, mild anemia and jaundice. Dark yellow fluid in the abdominal cavity was observed at necropsy. Fibrin and clotted blood were adhered to the pericardium and lung, primarily in the diaphragmatic lobes. The liver was enlarged, and the capsular surface was irregular with clear areas and petechiae. At the cut surface, the liver was irregular, firm and edematous, and several hemorrhagic channels could be observed. Areas of fibrosis through the parenchyma and whitish thrombi occluding the great vessels were also observed. The livers of 10 cows that not died were condemned at slaughter for lesions of fasciolosis similar to those observed at necropsy. Microscopically, the liver showed areas of coagulation necrosis, extensive hemorrhages in the streaks or foci and disruption of the parenchyma with neutrophil and eosinophil infiltration. Fibrosis and bile duct proliferation were also observed. Immature Fasciola hepatica flukes were observed in the parenchyma surrounded by degenerated hepatocytes, neutrophils, eosinophils, and hemorrhages. The outbreak occurred on a farm located in an area endemic for fasciolosis, although the acute form of the disease is not common in cattle in this region. It is likely that the cows were infected by F. hepatica metacercariae released in the late fall or early spring in the rice stubble where the herd was grazing prior to calving. Although mortality due to fasciolosis in cattle is infrequent, outbreaks can occur and treatments that are effective in both the immature and adult forms of the parasite should be administered to prevent economic losses.

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The purpose of this investigation was to demonstrate the feasibility of a biopsy technique by performing serial evaluations of tissue samples of the forelimb superficial digital flexor tendon (SDFT) in healthy horses and in horses subjected to superficial digital flexor tendonitis induction. Eight adult horses were evaluated in two different phases (P), control (P1) and tendonitis-induced (P2). At P1, the horses were subjected to five SDFT biopsies of the left forelimb, with 24 hours (h) of interval. Clinical and ultrasonographic (US) examinations were performed immediately before the tendonitis induction, 24 and 48 h after the procedure. The biopsied tendon tissues were analyzed through histology. P2 evaluations were carried out three months later, when the same horses were subjected to tendonitis induction by injection of bacterial collagenase into the right forelimb SDFT. P2 clinical and US evaluations, and SDFT biopsies were performed before, and after injury induction at the following time intervals: after 24, 48, 72 and 96 h, and after 15, 30, 60, 90, 120 and 150 days. The biopsy technique has proven to be easy and quick to perform and yielded good tendon samples for histological evaluation. At P1 the horses did not show signs of localised inflammation, pain or lameness, neither SDFT US alterations after biopsies, showing that the biopsy procedure per se did not risk tendon integrity. Therefore, this procedure is feasible for routine tendon histological evaluations. The P2 findings demonstrate a relation between the US and histology evaluations concerning induced tendonitis evolution. However, the clinical signs of tendonitis poorly reflected the microscopic tissue condition, indicating that clinical presentation is not a reliable parameter for monitoring injury development. The presented method of biopsying SDFT tissue in horses enables the serial collection of material for histological analysis causing no clinical signs and tendon damage seen by US images. Therefore, this technique allows tendonitis to be monitored and can be considered an excellent tool in protocols for evaluating SDFT injury.

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JÄKÄLA-algoritmi (Jatkuvan Äänitehojakautuman algoritmi Käytävien Äänikenttien LAskentaan) ja sen NUMO- ja APPRO-laskentayhtälöt perustuvat käytävällä olevan todellisen äänilähteen kuvalähteiden symmetriaan. NUMO on algoritmin numeerisen ratkaisun ja APPRO likiarvoratkaisun laskentayhtälö. Algoritmia johdettaessa oletettiin, että absorptiomateriaali oli jakautunut tasaisesti käytävän ääntä heijastaville pinnoille. Suorakaiteen muotoisen käytävän kuvalähdetason muunto jatkuvaksi äänitehojakautumaksi sisältää kolme muokkausvaihetta. Aluksi suorakaiteen kuvalähdetaso muunnetaan neliön muotoiseksi. Seuraavaksi neliön muotoisen kuvalähdetason samanarvoiset kuvalähteet siirretään koordinaattiakselille diskreetiksi kuvalähdejonoksi. Lopuksi kuvalähdejono muunnetaan jatkuvaksi äänitehojakautumaksi, jolloin käytävän vastaanottopisteen äänenpainetaso voidaan laskea integroimalla jatkuvan äänitehojakautuman yli. JÄKÄLA-algoritmin validiteetin toteamiseksi käytettiin testattua kaupallista AKURI-ohjelmaa. AKURI-ohjelma antoi myös hyvän käsityksen siitä, miten NUMO- ja APPRO-yhtälöillä lasketut arvot mahdollisesti eroavat todellisilla käytävillä mitatuista arvoista. JÄKÄLA-algoritmin NUMO- ja APPRO-yhtälöitä testattiin myös vertaamalla niiden antamia tuloksia kolmen erityyppisen käytävän äänenpainetasomittauksiin. Tässä tutkimuksessa on osoitettu, että akustisen kuvateorian pohjalta on mahdollista johtaa laskenta-algoritmi, jota voidaan soveltaa pitkien käytävien äänikenttien pika-arvioinnissa paikan päällä. Sekä teoreettinen laskenta että käytännön äänenpainetasomittaukset todellisilla käytävillä osoittivat, että JÄKÄLA-algoritmin yhtälöiden ennustustarkkuus oli erinomainen ideaalikäytävillä ja hyvä niillä todellisilla käytävillä, joilla ei ollut ääntä heijastavia rakenteita. NUMO- ja APPRO-yhtälöt näyttäisivät toimivan hyvin käytävillä, joiden poikkileikkaus oli lähes neliön muotoinen ja joissa pintojen suurin absorptiokerroin oli korkeintaan kymmenen kertaa pienintä absorptiokerrointa suurempi. NUMO- ja APPRO-yhtälöiden suurin puute on, etteivät ne ota huomioon pintojen erilaisia absorptiokertoimia eivätkä esineistä heijastuvia ääniä. NUMO- ja APPRO- laskentayhtälöt poikkesivat mitatuista arvoista eniten käytävillä, joilla kahden vastakkaisen pinnan absorptiokerroin oli hyvin suuri ja toisen pintaparin hyvin pieni, ja käytävillä, joissa oli massiivisia, ääntä heijastavia pilareita ja palkkeja. JÄKÄLA-algoritmin NUMO- ja APPRO-yhtälöt antoivat tutkituilla käytävillä kuitenkin selvästi tarkempia arvoja kuin Kuttruffin likiarvoyhtälö ja tilastollisen huoneakustiikan perusyhtälö. JÄKÄLA-algoritmin laskentatarkkuutta on testattu vain neljällä todellisella käytävällä. Algoritmin kehittämiseksi tulisi jatkossa käytävän vastakkaisia pintoja ja niiden absorptiokertoimia käsitellä laskennassa pareittain. Algoritmin validiteetin varmistamiseksi on mittauksia tehtävä lisää käytävillä, joiden absorptiomateriaalien jakautumat poikkeavat toisistaan.

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The purpose of the thesis is to classify suppliers and to enhance strategic purchasing in the case company. Supplier classification is conducted to fulfill the requirements of the company quality manual and international quality standards. To gain more benefit, a strategic purchasing tool, Kraljic’s purchasing portfolio and analytical hierarchy process are utilized for the base of supplier classification. Purchasing portfolio is used to give quick and easy visual insight on product group management form the viewpoint of purchasing. From the base on purchasing portfolio alternative purchasing and supplier strategies can be formed that enhance the strategic orientation of purchasing. Thus purchasing portfolio forces the company to orient on proactive and strategic purchasing. As a result a survey method for implementing purchasing portfolio in the company is developed that exploits analytical hierarchy process. Experts from the company appoint the categorization criteria and in addition, participate in the survey to categorize product groups on the portfolio. Alternative purchasing strategies are formed. Suppliers are classified depending on the importance and characteristics of the product groups supplied.

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Abstract: Platelet-rich plasma (PRP) is a product easy and inxpesnsive, and stands out to for its growth factors in tissue repair. To obtain PRP, centrifugation of whole blood is made with specific time and gravitational forces. Thus, the present work aimed to study a method of double centrifugation to obtain PRP in order to evaluate the effective increase of platelet concentration in the final product, the preparation of PRP gel, and to optimize preparation time of the final sample. Fifteen female White New Zealand rabbits underwent blood sampling for the preparation of PRP. Samples were separated in two sterile tubes containing sodium citrate. Tubes were submitted to the double centrifugation protocol, with lid closed and 1600 revolutions per minute (rpm) for 10 minutes, resulting in the separation of red blood cells, plasma with platelets and leucocytes. After were opened and plasma was pipetted and transferred into another sterile tube. Plasma was centrifuged again at 2000rpm for 10 minutes; as a result it was split into two parts: on the top, consisting of platelet-poor plasma (PPP) and at the bottom of the platelet button. Part of the PPP was discarded so that only 1ml remained in the tube along with the platelet button. This material was gently agitated to promote platelets resuspension and activated when added 0.3ml of calcium gluconate, resulting in PRP gel. Double centrifugation protocol was able to make platelet concentration 3 times higher in relation to the initial blood sample. The volume of calcium gluconate used for platelet activation was 0.3ml, and was sufficient to coagulate the sample. Coagulation time ranged from 8 to 20 minutes, with an average of 17.6 minutes. Therefore, time of blood centrifugation until to obtain PRP gel took only 40 minutes. It was concluded that PRP was successfully obtained by double centrifugation protocol, which is able to increase the platelet concentration in the sample compared with whole blood, allowing its use in surgical procedures. Furthermore, the preparation time is appropriate to obtain PRP in just 40 minutes, and calcium gluconate is able to promote the activation of platelets.

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The number of molecular diagnostic assays has increased tremendously in recent years.Nucleic acid diagnostic assays have been developed, especially for the detection of human pathogenic microbes and genetic markers predisposing to certain diseases. Closed-tube methods are preferred because they are usually faster and easier to perform than heterogenous methods and in addition, target nucleic acids are commonly amplified leading to risk of contamination of the following reactions by the amplification product if the reactions are opened. The present study introduces a new closed-tube switchable complementation probes based PCR assay concept where two non-fluorescent probes form a fluorescent lanthanide chelate complex in the presence of the target DNA. In this dual-probe PCR assay method one oligonucleotide probe carries a non-fluorescent lanthanide chelate and another probe a light absorbing antenna ligand. The fluorescent lanthanide chelate complex is formed only when the non-fluorescent probes are hybridized to adjacent positions into the target DNA bringing the reporter moieties in close proximity. The complex is formed by self-assembled lanthanide chelate complementation where the antenna ligand is coordinated to the lanthanide ion captured in the chelate. The complementation probes based assays with time-resolved fluorescence measurement showed low background signal level and hence, relatively high nucleic acid detection sensitivity (low picomolar target concentration). Different lanthanide chelate structures were explored and a new cyclic seven dentate lanthanide chelate was found suitable for complementation probe method. It was also found to resist relatively high PCR reaction temperatures, which was essential for the PCR assay applications. A seven-dentate chelate with two unoccupied coordination sites must be used instead of a more stable eight- or nine-dentate chelate because the antenna ligand needs to be coordinated to the free coordination sites of the lanthanide ion. The previously used linear seven-dentate lanthanide chelate was found to be unstable in PCR conditions and hence, the new cyclic chelate was needed. The complementation probe PCR assay method showed high signal-to-background ratio up to 300 due to a low background fluorescence level and the results (threshold cycles) in real-time PCR were reached approximately 6 amplification cycles earlier compared to the commonly used FRET-based closed-tube PCR method. The suitability of the complementation probe method for different nucleic acid assay applications was studied. 1) A duplex complementation probe C. trachomatis PCR assay with a simple 10-minute urine sample preparation was developed to study suitability of the method for clinical diagnostics. The performance of the C. trachomatis assay was equal to the commercial C. trachomatis nucleic acid amplification assay containing more complex sample preparation based on DNA extraction. 2) A PCR assay for the detection of HLA-DQA1*05 allele, that is used to predict the risk of type 1 diabetes, was developed to study the performance of the method in genotyping. A simple blood sample preparation was used where the nucleic acids were released from dried blood sample punches using high temperature and alkaline reaction conditions. The complementation probe HLA-DQA1*05 PCR assay showed good genotyping performance correlating 100% with the routinely used heterogenous reference assay. 3) To study the suitability of the complementation probe method for direct measurement of the target organism, e.g., in the culture media, the complementation probes were applied to amplificationfree closed-tube bacteriophage quantification by measuring M13 bacteriophage ssDNA. A low picomolar bacteriophage concentration was detected in a rapid 20- minute assay. The assay provides a quick and reliable alternative to the commonly used and relatively unreliable UV-photometry and time-consuming culture based bacteriophage detection methods and indicates that the method could also be used for direct measurement of other micro-organisms. The complementation probe PCR method has a low background signal level leading to a high signal-to-background ratio and relatively sensitive nucleic acid detection. The method is compatible with simple sample preparation and it was shown to tolerate residues of urine, blood, bacteria and bacterial culture media. The common trend in nucleic acid diagnostics is to create easy-to-use assays suitable for rapid near patient analysis. The complementation probe PCR assays with a brief sample preparation should be relatively easy to automate and hence, would allow the development of highperformance nucleic acid amplification assays with a short overall assay time.

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Käänteisosmoosisuodatusta käytetään erityisesti teollisuuden jätevesien loppupuhdistuksessa. Suodatuksen ongelmana on kalvojen likaantuminen ja tukkiutuminen. Tässä työssä on aiempia tutkimuksia hyväksikäyttäen tutkittu käänteisosmoosiin tulevan veden esikäsittelemistä niin, että kalvojen likaantumiselta vältyttäisiin. Menetelmien vertailussa on käytetty erilaisia veden laadusta kertovia parametreja. Ongelmallisimmiksi aineksiksi huomattiin orgaaninen aines ja jotkin veteen liuenneet ionit. Kiintoaineen erottaminen ei ole ollut suuri ongelma, sillä sen saa poistettua tavallisesti käytetyillä rakeissuodatuksella, laskeutuksella, flotaatiolla ja kalvosuodatuksella. Orgaanista ainesta on saatu erotettua erityisesti hapettamalla, aktiivilieteprosessilla ja biologisella aktiivihiilisuodattimella. Mikro- ja ultrasuodatusta käytetään usein juuri ennen käänteisosmoosia poistamaan erityisesti kolloidista materiaalia ja joitain liuenneita ioneja. Flokkien muodostaminen koagulaatiossa ja flokkulaatiossa parantaa lähes kaikkien menetelmien toimivuutta selvästi. Veden puhdistuksessa käytetyt kemikaalit voivat myös liika-annosteltuina liata kalvoja. Vesien pitoisuuksissa eri ainesten osalta on huomattavia eroja, joten puhdistettava vesi on hyvä analysoida etukäteen parhaiden käsittelymenetelmien valitsemiseksi.