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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

An analysis of the utility of quantitative faecal immunochemical tests in screening and symptomatic populations

Mcdonald, Paula Jane January 2016 (has links)
Background: It has been demonstrated, in 4 large randomised control trials (RCT), that screening for colorectal cancer (CRC) using annual or biennial guaiac faecal occult blood tests (gFOBT) reduces mortality and incidence. The faecal immunochemical test (FIT) uses technology that is analytically more sensitive and specific for human haemoglobin (Hb) than gFOBT. Methods: An evaluation of the OC-Sensor Diana quantitative FIT analyser and prospective analysis of a single estimate of faecal haemoglobin concentration (f-Hb) in two clinical settings; the Scottish Bowel Screening Programme and patients referred from primary care to endoscopy services. Results: Uptake, in the cohort offered screening with FIT as a first-line test, was 4.8% higher than that seen contemporaneously in the Scottish Bowel Screening Programme. This returned to pre study levels when the study ceased and gFOBT was reintroduced. The cohort offered quantitative FIT had a positivity of 2.4% compared to 2.1% in the programme overall. Clinical outcomes, during the evaluation period, in the study cohort and the screening programme were similar. 40,125 participants returned a FIT sample device and 38,720 had their f-Hb measured. An observational study of f-Hb by sex and age, using the 97.5th percentile as a potential upper reference limit, and 90% confidence intervals (CI) showed 519 ng Hb/ml buffer (90% CI: 468 – 575) for men and 283 ng Hb/ml buffer (90% CI: 257 – 316) for women. When the data was partitioned by age quintile, f-Hb increased with age in both sexes. Quantitative FIT and endoscopy were completed by 280 patients referred from primary care for endoscopy (median age: 63 years, range: 18 to 84 years), 59.6% were female. Six (2.1%) participants had CRC, 23 (8.2%) high-risk adenoma (HRA: > 3 adenomas or any > 1 cm), 31 (11.1%) low-risk adenoma (LRA), and 26 (9.3%) inflammatory bowel disease (IBD) as the most serious diagnosis. Those with CRC had median f-Hb of > 1000 ng Hb/ml buffer. Using f-Hb with a cut-off of 50 ng Hb/ml buffer, negative predictive values of 100%, 94.4%, 93.4% and 93.9% were found for CRC, HRA, LRA and IBD. Conclusions: The introduction of quantitative FIT into population screening and symptomatic settings has the potential to optimise referral for endoscopy for those who have evidence of small amounts of bleeding, thereby improving outcomes and reducing the current burden on endoscopy services.
2

Immunochemical Studies on the family of Biotin Binding Proteins

Subramanian, N 01 1900 (has links)
Investigations detailed in this thesis constitue a part of continuing programme of research work undertaken in this laboratory on vitamin binding proteins. Avidin from the chicken egg white, streptavidin &om the bacterium Streptromyces avidin and biotin binding proteins (BBP-I and BBP-11) from chicken egg yolk constitute a family of proteins that bind the vitamin biotin with extremely high affinities. The yolk BBPs are involved in the deposition of the vitamin in the developing oocyte in chicks whereas an antimicrobial function has been attributkl to avidin.. The fact that all these proteins bind the vitamin in the same manner, unlike biotin-dependent enzymes, indicates that the structural features involved in ligand binding could be similar, if not identical in these proteins. To delineate the basis of putative structural similarity among these proteins, studies were carried out using antibodies as the immunological probes. Avidin, a homotetremer glycoprotein, with a subunit Mr of 17,000 has been purified to homogeneity from chicken egg white using a novel procedure involving ammonium sulphate fractionation, ethanol precipitation and S-Sepharose column chromatography. Despite their lesser abundance in chicken egg yolk associated with a large amount of interfering lipids during the purification, both BBP-I (monomer and shown to be precursor for BBP-11) and BBP-I1 (tetramer) have been purified to homogeneity by employing a common method using butanol extraction to remove the lipids, DEAE-Sephacel column chromatography, biotin-AH-Sepharose affinity chromatography and fast performance liquid chrometography (FPLC) system. The purity of all these proteins was confirmed by SDS-PAGE analysis.
3

Biochemical and immunochemical investigation of some South African strains of the human malaria parasite, Plasmodium falciparum

Stoltz, Anton Carel 11 February 2013 (has links)
Malaria parasites are responsible for an increase in the morbidity and mortality in several tropical regions in Southern Africa. In this thesis, research was undertaken on Plasmodium, which is responsible for more than 95% of these cases. Although pharmacological prophylaxis is available, a worldwide resistance against existing drugs have been encountered. A study on chloroquineresistance in North-Eastern Transvaal in 1988, indicated that 11% of the strains in this area were resistant against chloroquine. Only 78% of these parasites were sensitive to the new drug, Mefloquine, which could serve as a substitute in chloroquine-resistant infections. Furthermore, no strain was found to be resistant or insensitive to both anti-malarial drugs. Malaria parasites can be obtained for research purposes from long term in vitro cultures. The initiation of cultures of some wild isolates of P.falciparum appears to be problematic at certain levels above sea-level. The gas composition of the medium was identified as a probable cause due to its dependence on the partial pressures of gasses at different heights above sealevel. The toxic effect of a too high oxygen concentration on the parasite, caused by the lower atmospheric pressure of the Highveld area, was prevented after the concentration of dissolved carbon dioxide in the medium was increased through equilibration with the special gas mixture. Possible shortcomings in the long-term culture method for malaria parasites that could retard optimum growth, were also investigated. Local parasite isolates could be supported on medium enriched with bovine serum although the growth rate was lower than when human serum was used. By increasing the frequency of medium replacement with progressing parasitemia, less stress were placed on the system since parasites was exposed for shorter periods and to lower concentrations of byproducts such as lactic acid. In addition, the ATP-concentration in infected cultures decreased by nearly 50 % over a growth period of 4 days. The stress in the host cell was reflected by the decrease in the total adenyl-nucleotide pool and the increase in AMP-concentration. An increase in the intracellular IMP-concentration indicated that the purine salvage pathway was inhibited which may explain the decrease in the ATP-concentration. It therefore appears that the regular replacement of medium and replenishment of erythrocytes only partially contribute to the successful establishment of malaria cultures. More research is necessary to identify the factors that are responsible for the inhibition of the purine salvage pathway. The stress placed on the human body by the parasite is complicated by the thrombocytopenia observed in some infections. Increases in the concentrations of thrombocyte-associated immunoglobulin G and M which are a characteristic for this condition, can be determined by a modified microo-method developed in our laboratory. By monitoring the parasite-infected patient over a period of time with the micro-method, the increase in thrombocytes and decrease in thrombocyte-associated antibodies were correlated with the recuperation of the patient. This method does not destroy the thrombocytes, thereby allowing displacement studies to be undertaken with purified parasite antigens of synthetic peptides. An investigation of parasite-infected erythrocytes by means of light microscopy, transmission and scanning electronmicroscopy, indicated that the local isolate could be composed of a mixture of strains, of which some have the ability to induce knobs on the erythrocyte. Furthermore, the investigation illustrated that fast fixation with gluteraldehyde is superior to slow fixation when transmission electronmicroscopy is performed. However, no difference could be observed when scanning electron microscopy was performed on infected erythrocytes that had been fixed by either of these methods. AFRIKAANS : Malaria parasiete is verantwoordelik vir 'n toenemende morbiditeit sowel as mortaliteit in verskeie tropiese streke in Suider-Afrika waarvan meer as 95 % van die gevalle deur Plasmodium falciparum veroorsaak word. Navorsing in die tesis is gevolglik op hierdie parasiet toegespits. Ten spyte daarvan dat far'makologiese profilakse toegepas word, kan malaria nog steeds opgedoen word as gevolg van n wereldwye weerstandigheid teen bestaande geneesmiddels. 'n Ondersoek van die klorokien-weerstandigheidstatus in die Noord-Oostelike Transvaal het in 1988 getoon dat 11 % van die stamme in die area weerstandig is teenoor klorokien. Slegs 78% van die parasiete was sensitief vir die nuwe middel, Meflokien, wat as moontlike plaasvervanger in klorokien-weerstandige parasietinfeksies gebruik kan word. Geen parasietstam was egter weerstandig of onsensitief teen beide middels nie. Langtermyn kultuurkweking van malaria parasiete is essensieël vir die verkryging van uitgangsmateriaal vir navorsing op die parasiet. Dit blyk egter dat inisiasie van kulture van wilde stamme van P. falciparum problematies by sekere hoogtes bo seespieël is. Die gassamestelling van die medium is as 'n moontlike oorsaak gëidentifiseer aangesien dit afhanklik is van die parsiële drukke van gasse by verskillende hoogtes bo seespieël. Die toksiese effek van te hoë suurstofkonsentrasies op die parasiet a.g.v. die laer atmosferiese druk op die Hoëveldstreek, is oorkom deur die konsentrasie van opgeloste koolsuurgas in die medium te verhoog deur vooraf 'n spesiale gasmengsel daardeur te borrel. Moontlike tekortkominge in die langtermyn kultuur metode vir malaria parasiete wat optimale groei kan belemmer, is ook ondersoek. Plaaslike parasietstamme kon op medium wat verryk is met beesserum onderhou word, alhoewel die groeitempo laer is as wanneer mensserum gebruik word. 'n Toenemende tempo van mediumvervanging soos die parasitemia in kulture toeneem, het getoon dat minder stres op die sisteem geplaas word deurdat die parasiete vir 'n korter periode en aan laer konsentrasies van byprodukte soos melksuur blootgestel word. Die ATP-konsentrasies in gëinfekteerde kulture daal egter met ongeveer die helfte oor 'n groeiperiode van 4 dae. Tesame hiermee, is daar ook 'n daling in die totale adeniel-nukleotied poel van die gëinfekteerde rooibloedsel en 'n styging in die AMP-konsentrasie wat die stres in die gasheersel weerspieël. 'n Verhoging in die intrasellulêre IMP-konsentrasie dui op 'n moontlike inhibisie van die purienherwinningspadweg wat die verlaagde ATP-konsentrasie mag verklaar. Uit die studie blyk dit dus of meer gereelde vervanging van medium en toevoeging van rooibloedselle slegs 'n gedeeltelike bydrae maak tot die suksesvolle vestiging van malariakulture. Die identifikasie van die faktore wat lei tot die inhibisie van die purienherwinningspadweg, verg nog verdere ondersoeke. Die stres wat die parasiet in die menslike liggaam veroorsaak, word ook weerspieël deur onderandere die trombositopenie wat in sommige infeksies waargeneem word. Verhogings in die konsentrasie van trombosiet-geassosieërde immunoglobuliene G en M wat kenmerkend is van die toestand, kan gemeet word deur 'n gemodifiseerde mikrometode wat in ons laboratoriums ontwikkel is. Deur die parasiet-gëinfekteerde pasiët oor 'n paar dae met die mikrometode te monitor, kon die verhoging in trombosiete en afname in trombosiet-geassosieërde antiliggame met herstel van die pasiënt gekorreleer word. Die metode veroorsaak geen skade aan die trombosiete nie sodat antigeenverplasingstudies ook na die tyd gedoen kan word. In 'n ondersoek van die parasiet met behulp van ligmikroskopie, deurstraal- sowel as skandeer-elektronmikroskopie, is gevind dat die plaaslike isolaat moontlik uit 'n mengsel van stamme bestaan, waarvan sommige die vermoë het om knoppe op die rooibloedsel te induseer. Verder het die ondersoek getoon dat indien deurstraal-elektronmikroskopie gebruik word, 'n vinnige fikseringsmetode met gluteraldehied beter is as 'n stadige fikseringsmetode. In vergelyking hiermee kon geen verskil waargeneem word met skandeer-elektronmikroskopie van geparasiteerde rooibloedselle wat met enige van hierdie metodes gefikseer is nie. Copyright / Dissertation (MSc)--University of Pretoria, 1992. / Biochemistry / unrestricted
4

Ανοσολογική διερεύνηση ασθενών με μυελοδυσπλαστικά σύνδρομα. Η σημασία των ανοσολογικών διαταραχών για την πρόγνωση και η πιθανή συσχέτισή τους με την παθολογική αιμοποίηση

Συμεωνίδης, Αργύρης 13 May 2010 (has links)
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5

Ανοσοϊστοχημική μελέτη της κατανομής των γεννητικών στεροειδών ορμονών και των ισοενζύμων ΒΒ και ΜΜ της κρεατινοκινάσης σε καρκινώματα της ουροδόχου κύστεως

Παναγιωτοπούλου, Κωνσταντίνα 23 April 2010 (has links)
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6

Διερεύνηση σχέσεως μονοσθενών, δισθενών ιόντων και LH-RH με κρυψορχία ηλικίας 1 έως 11 χρόνων

Ζαρακοβίτης, Ιωάννης 10 May 2010 (has links)
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7

Diagnosing colorectal cancer in primary care : the value of symptoms, faecal immunochemical tests, faecal calprotectin and anaemia

Högberg, Cecilia January 2017 (has links)
Background: Colorectal cancer (CRC) is the third most common cancer in men and the second most common in women worldwide. Adenomas can be precursors to CRC, and inflammatory bowel disease (IBD) can present with the same symptoms as CRC. The majority of patients with CRC initially consult primary care. Symptoms associated with CRC are also common among primary care patients, but seldom caused by any significant disease. Reliable diagnostic aids would be helpful in deciding which patients to refer. Faecal immunochemical tests (FITs) are commonly used for this purpose in primary care in Sweden, but there is little evidence to support this use. Faecal calprotectin (FC) has been suggested as an additional test. Aim: To explore how doctors in primary care investigate patients with suspected CRC, the value of FITs, symptoms and presence of anaemia in diagnosing CRC and adenomas in primary care, and whether FC tests could contribute to diagnosis. Methods: Three studies (1-3) were carried out in Region Jämtland Härjedalen, Sweden. There was no screening programme for CRC. We used a point of care qualitative dip-stick 3-sample FIT with a cut-off of 25-50μg haemoglobin/g faeces, and a calprotectin enzyme-linked immunosorbent assay (ELISA) test with a cut-off of 100 μg/g faeces. 1: A retrospective, population-based study including all patients diagnosed with CRC or adenomas with high-grade dysplasia (HGD) during the period 2005-2009 that initially consulted primary care. Symptoms, FIT results, anaemia and time to diagnosis were retrieved from medical records. Sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated from FIT results at the region’s health centres 2008- 2009. (Paper I.) 2: A prospective cohort study including consecutive patients where primary care doctors requested FITs and/or FC tests, at four health centres, from 30 Jan 2013 to 31 May 2014. FITs, FC tests, haemoglobin and iron deficiency tests were analysed; patients and doctors answered questionnaires about symptoms. Patients were examined with bowel imaging or followed for two years. Findings of CRC, adenomas with HGD, adenomas with low grade dysplasia (LGD) ≥1 cm and IBD were registered. (Papers II and III.) 3: A qualitative study of interviews with eleven primary care doctors. We explored what made them suspect CRC, and their practices regarding investigation and referral with particular attention to their use of FITs. Qualitative content analysis with an inductive approach was used for the analysis. (Paper IV.) Results: 1: Paper I: Of 495 patients 323 (65.3%) started the investigation in primary care. FITs were analysed in 215. In 23 cases with CRC, FITs were negative; 15 (65.2%) had anaemia. In 33 cases with CRC, FITs were performed due to asymptomatic anaemia; 10 (30.3%) had negative FITs. The time from start of investigation, to the diagnosis of CRC or adenomas with HGD, was significantly longer for patients with negative FITs. 2: 377 patients (9 diagnosed with CRC, 10 with IBD) were included. Paper II: Concordance of positive answers about symptoms from patients and doctors was generally low. Rectal bleeding (recorded by 43.5% of patients and 25.6% of doctors) was the only symptom related to CRC and IBD. The FIT showed a better PPV than rectal bleeding for CRC and IBD. When patients recorded rectal bleeding, the FIT had a PPV of 22.6% and a NPV of 98.9% for CRC and IBD. Paper III: The best test for detecting CRC and IBD was the combination of a positive FIT and/or anaemia with a sensitivity, specificity, PPV and NPV of 100%, 61.7%, 11.7% and 100% respectively. The FC test had no additional value to the FIT alone. The sensitivity, specificity, PPV and NPV of the FIT for CRC in study 1 was estimated at 88.4%, 73.3%, 6.2% and 99.7% respectively. In study 2, corresponding figures were 88.9%, 67.4%, 6.3% and 99.6% respectively. 3: Paper IV: We identified four categories: “Careful listening – with awareness of the pit-falls”, “tests can help – the FIT can also complicate the diagnosis”, “to refer or not to refer – safety margins are necessary”, and “growing more confident – but also more humble”. All doctors had found their own way to handle FIT results in the absence of guidelines. Conclusion: The diagnostic process when suspecting CRC can be described as navigating uncertain waters with safety margins. FITs were often used by primary care doctors but with considerable variations in interpretation and handling of results. Rectal bleeding was the only symptom related to CRC and IBD, but the FIT showed a better PPV than rectal bleeding. The combination of a negative FIT and no anaemia may be useful as a rule-out test when CRC is suspected in primary care, and this potentially also applies when patients present with rectal bleeding. Further studies are needed to confirm this and to determine the optimal FIT cut-off value for this use.
8

Febre reumática: Perfis imunoquímicos desenvolvidos por antígenos celulares e extracelulares do Streptococcus pyogenes e isotipos de anticorpos de pacientes com a doença / Rheumatic fever: Immunochemical profiles developed by cellular and extracellular antigens of Streptococcus pyogenes and antibody isotypes from patients with the disease

Pavan, Maria de Fatima Borges 05 December 1996 (has links)
A febre reumática é uma das sequelas da infecção causada por Streptococcus pyogenes, afetando notadamente crianças e jovens, com altas taxas de morbidade e mortalidade em várias regiões do mundo, incluindo Brasil. Perfis imunoquímicos desenvolvidos por antígenos celulares e extracelulares desta bactéria e isotipos de anticorpos presentes em pacientes com febre reumática foram averiguados, em virtude da escassez de informação a este respeito na literatura. Na primeira fase do trabalho, as condições para o preparo de antígenos, bem como de técnicas, em especial a técnica super-micro de neutralização de anticorpos (Ac) anti-estreptolisina O (ASLO) foram padronizadas. Na segunda etapa, foram identificadas as bandas de antígenos celulares e extracelulares reconhecidas por 56 soros de pacientes com febre reumática (Grupo A), 91 soros de indivídos sem diagnóstico de sequelas não-supurativas da infecção, mas com títulos baixos, médios e altos de Ac ASLO (Grupo B), e 41 soros de crianças sem infecção (Grupo C). Em pacientes com febre reumática, Acs IgG e IgA foram detectados, mas Acs IgM não foram encontrados. Anticorpos IgG de pacientes do grupo A reconheceram um total de 30 bandas do antígeno celular, sendo específicas 18 (14, 17, 19,22,23,28,29,32,36, 73, 83, 102, 104, 108, 11 0, 116, 118 e 125 kDa). O resto das 12 bandas foram consideradas não específicas por serem reconhecidas por soros do grupo C. Um total de 19 bandas do antígeno extracelular foi reconhecido por Acs IgG do grupo A, sendo apenas 3 bandas (40, 46, 125 kDa) específicas. No grupo C, Acs IgA não foram detectados. Um total de 14 bandas (23, 30, 38, 42, 43, 46, 48, 54, 57, 60, 67, 73, 78 e 116 kDa) do antígeno celular foram identificadas por Acs IgA do grupo A. No antígeno extracelular, 8 bandas (38, 48, 54, 60, 67,\" 73, 78 e 95 kDa) foram reconhecidas por Acs IgA do mesmo grupo. Critério adotado de combinar dados imunoquímicos ou seja, bandas iguais ou maiores que 102 kDa e/ou bandas iguais ou menores que 29 kDa do antígeno celular de S. pyogenes, acrescido da presença de Acs IgA, possibilitaram a discriminação de pacientes com febre reumática e de não infectados, fornecendo máxima sensibilidade, especificidade, eficiência, bem como de valores preditivos de resultados positivo e negativo. Ademais, os achados de Acs IgG contra banda de 28 kDa que está relacionada a antígeno do tecido cardíaco, um dos 6 perfís imunoquímicos fornecidos por antígeno celular e Acs IgG do presente estudo, e a presença de Acs IgA parecem constituir sinais precoces associados à patogênese da febre reumática. Desta forma no grupo B, 9 pacientes revelaram a banda de 23 kDa do antígeno celular, destes 7 apresentaram perfis compatíveis com os do grupo A, sendo que apenas 1 deles não apresentou Acs IgA. Os dados sugerem que estes pacientes tendem a evoluir para a forma sintomática da febre reumática, requerendo acompanhamento clínico e laboratorial cuidadoso. / The rheumatic fever is one of the sequelae from the Streptococcus pyogenes infection, affecting manly children and young persons, with high rates of morbidity and mortality in many regions of the world. Immunological profiles developed by cellular and extracellular antigens from this bacterium and antibody isotypes found in the patients with rheumatic fever were investigated, due to the scarcity of information about this aspect in the literature. In the first step of this work, conditions to prepare antigens, as well as of techniques, in particular the super-micro technique for the neutralization of antistreptolysin O (ASLO) antibodies (Abs), were standardized. In the second step, bands of cellular and extracellular antigens recognized by 56 serum sera from patients with rheumatic fever (Grupo A), 91 sera from individuals with no diagnosis of supurative sequelae from the infection, but with low, moderate and high ASLO titers (Group B), and 41 sera from children with no infection (Group C) were identified. In patients with rheumatic fever, IgG and IgA antibodies were found, but IgM antibodies were absent. IgG antibodies from rheumatic fever patients recognized 30 bands of the cellular antigens, of these 18 were specific (14,17,19,22,23,28,29,32,36,73,83,102, 104, 108, 110, 116, 118 e 125 kDa). The remaing 12 bands were considered nonspecific because they were recognized by sera from the group C. A total of 19 bands of the extracellular antigen were recognized by IgG Abs from the group A and 3 of these (40, 46 and 125 kDa) were specific. In the group C, no IgA Abs were detected. A total of 14 specific bands (23, 30, 38, 42, 43, 46, 48, 54, 57, 60, 67, 73, 78 and 116 kDa) of the cellular antigen were identified by IgA Abs from the group A. The extracellular antigen had 8 bands (38, 48, 54, 60, 67, 73, 78 and 95 kDa) recognized by IgA Abs from the same group. A criterion adopted of combining immunchemical data, i.e. bands equal or higher than 102 kDa and/or bands equal or lower than 29 kDa of the cellular antigen of S. pyogenes plus the IgA Ab finding, allowed to discriminate rheumatic fever from noninfected individuals, providing maximum sensitivity, specificity, efficiency as well as predictives of positive and negative results. Moreover, the findings of IgG Abs to 23 kDa of the cellular antigen which is associated to the heart tissue antigen, one of those 6 immunochemical profiles provided by cellular antigen and IgG Abs from this study, and the presence of IgA Abs seem to constitute early immunologic signals related to the pathogenesis of the rhematic fever. Thus in the group B, 9 patients revealed a 23 kDa band of cellular antigen, 7 of these showed immunochemical profiIes consistent with those from the group A, and lacking IgA Abs in onIy one of them. The data suggest these patients are prone to deveIop rheumatic fever, requiring a close clinical and laboratory follow-up.
9

Febre reumática: Perfis imunoquímicos desenvolvidos por antígenos celulares e extracelulares do Streptococcus pyogenes e isotipos de anticorpos de pacientes com a doença / Rheumatic fever: Immunochemical profiles developed by cellular and extracellular antigens of Streptococcus pyogenes and antibody isotypes from patients with the disease

Maria de Fatima Borges Pavan 05 December 1996 (has links)
A febre reumática é uma das sequelas da infecção causada por Streptococcus pyogenes, afetando notadamente crianças e jovens, com altas taxas de morbidade e mortalidade em várias regiões do mundo, incluindo Brasil. Perfis imunoquímicos desenvolvidos por antígenos celulares e extracelulares desta bactéria e isotipos de anticorpos presentes em pacientes com febre reumática foram averiguados, em virtude da escassez de informação a este respeito na literatura. Na primeira fase do trabalho, as condições para o preparo de antígenos, bem como de técnicas, em especial a técnica super-micro de neutralização de anticorpos (Ac) anti-estreptolisina O (ASLO) foram padronizadas. Na segunda etapa, foram identificadas as bandas de antígenos celulares e extracelulares reconhecidas por 56 soros de pacientes com febre reumática (Grupo A), 91 soros de indivídos sem diagnóstico de sequelas não-supurativas da infecção, mas com títulos baixos, médios e altos de Ac ASLO (Grupo B), e 41 soros de crianças sem infecção (Grupo C). Em pacientes com febre reumática, Acs IgG e IgA foram detectados, mas Acs IgM não foram encontrados. Anticorpos IgG de pacientes do grupo A reconheceram um total de 30 bandas do antígeno celular, sendo específicas 18 (14, 17, 19,22,23,28,29,32,36, 73, 83, 102, 104, 108, 11 0, 116, 118 e 125 kDa). O resto das 12 bandas foram consideradas não específicas por serem reconhecidas por soros do grupo C. Um total de 19 bandas do antígeno extracelular foi reconhecido por Acs IgG do grupo A, sendo apenas 3 bandas (40, 46, 125 kDa) específicas. No grupo C, Acs IgA não foram detectados. Um total de 14 bandas (23, 30, 38, 42, 43, 46, 48, 54, 57, 60, 67, 73, 78 e 116 kDa) do antígeno celular foram identificadas por Acs IgA do grupo A. No antígeno extracelular, 8 bandas (38, 48, 54, 60, 67,\" 73, 78 e 95 kDa) foram reconhecidas por Acs IgA do mesmo grupo. Critério adotado de combinar dados imunoquímicos ou seja, bandas iguais ou maiores que 102 kDa e/ou bandas iguais ou menores que 29 kDa do antígeno celular de S. pyogenes, acrescido da presença de Acs IgA, possibilitaram a discriminação de pacientes com febre reumática e de não infectados, fornecendo máxima sensibilidade, especificidade, eficiência, bem como de valores preditivos de resultados positivo e negativo. Ademais, os achados de Acs IgG contra banda de 28 kDa que está relacionada a antígeno do tecido cardíaco, um dos 6 perfís imunoquímicos fornecidos por antígeno celular e Acs IgG do presente estudo, e a presença de Acs IgA parecem constituir sinais precoces associados à patogênese da febre reumática. Desta forma no grupo B, 9 pacientes revelaram a banda de 23 kDa do antígeno celular, destes 7 apresentaram perfis compatíveis com os do grupo A, sendo que apenas 1 deles não apresentou Acs IgA. Os dados sugerem que estes pacientes tendem a evoluir para a forma sintomática da febre reumática, requerendo acompanhamento clínico e laboratorial cuidadoso. / The rheumatic fever is one of the sequelae from the Streptococcus pyogenes infection, affecting manly children and young persons, with high rates of morbidity and mortality in many regions of the world. Immunological profiles developed by cellular and extracellular antigens from this bacterium and antibody isotypes found in the patients with rheumatic fever were investigated, due to the scarcity of information about this aspect in the literature. In the first step of this work, conditions to prepare antigens, as well as of techniques, in particular the super-micro technique for the neutralization of antistreptolysin O (ASLO) antibodies (Abs), were standardized. In the second step, bands of cellular and extracellular antigens recognized by 56 serum sera from patients with rheumatic fever (Grupo A), 91 sera from individuals with no diagnosis of supurative sequelae from the infection, but with low, moderate and high ASLO titers (Group B), and 41 sera from children with no infection (Group C) were identified. In patients with rheumatic fever, IgG and IgA antibodies were found, but IgM antibodies were absent. IgG antibodies from rheumatic fever patients recognized 30 bands of the cellular antigens, of these 18 were specific (14,17,19,22,23,28,29,32,36,73,83,102, 104, 108, 110, 116, 118 e 125 kDa). The remaing 12 bands were considered nonspecific because they were recognized by sera from the group C. A total of 19 bands of the extracellular antigen were recognized by IgG Abs from the group A and 3 of these (40, 46 and 125 kDa) were specific. In the group C, no IgA Abs were detected. A total of 14 specific bands (23, 30, 38, 42, 43, 46, 48, 54, 57, 60, 67, 73, 78 and 116 kDa) of the cellular antigen were identified by IgA Abs from the group A. The extracellular antigen had 8 bands (38, 48, 54, 60, 67, 73, 78 and 95 kDa) recognized by IgA Abs from the same group. A criterion adopted of combining immunchemical data, i.e. bands equal or higher than 102 kDa and/or bands equal or lower than 29 kDa of the cellular antigen of S. pyogenes plus the IgA Ab finding, allowed to discriminate rheumatic fever from noninfected individuals, providing maximum sensitivity, specificity, efficiency as well as predictives of positive and negative results. Moreover, the findings of IgG Abs to 23 kDa of the cellular antigen which is associated to the heart tissue antigen, one of those 6 immunochemical profiles provided by cellular antigen and IgG Abs from this study, and the presence of IgA Abs seem to constitute early immunologic signals related to the pathogenesis of the rhematic fever. Thus in the group B, 9 patients revealed a 23 kDa band of cellular antigen, 7 of these showed immunochemical profiIes consistent with those from the group A, and lacking IgA Abs in onIy one of them. The data suggest these patients are prone to deveIop rheumatic fever, requiring a close clinical and laboratory follow-up.
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Proteomová analýza účinků protinádorových léčiv a charakterizace mechanismů nádorové rezistence / Proteome analysis of anti-cancer drug effects and characterisation of drug resistance

Hrabáková, Rita January 2013 (has links)
Despite significant progress in the development of anti-cancer drugs, there is still a need for novel therapeutic strategies that would improve the outcome of cancer patients. Using proteomic technologies and cell lines with different phenotype of p53 tumour suppressor, we monitored cancer cell response to anti-cancer treatment with focus on the development of drug resistance. The different levels of metabolic proteins were identified in our study which may help to explain different anti-cancer activity of drugs with only a subtle difference in structure. More importantly, proteins associated with the development of drug resistance were identified and such expression changes have become a focus of interest. Our findings demonstrate a higher protein level of serine hydroxymethyltransferase, serpin B5 and calretinin in cancer cells resistant to Aurora kinase inhibitors. Such proteins promote the tumour growth with no apparent impact of p53 phenotype whilst voltage-dependent anion-selective channel protein 2 contributes to the development of resistance only in cells with functional p53 which is accompanied by the decreased level of elongation factor 2. On the other hand, cancer cells with loss of p53 appear to amplify alternative mechanisms such as protection against oxidative stress. The results...

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