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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.
71

Staging and tumor biological mechanisms of lymph node metastasis in invasive urinary bladder cancer

Aljabery, Firas January 2017 (has links)
Aim: To study the possibility of detecting lymph node metastasis in locally advanced urinary bladder cancer (UBC) treated with radical cystectomy (RC) by using preoperative positron emission tomography/computed tomography (PET/CT) and peroperative sentinel node biopsy (SNB) technique. We also investigate the clinical significance of macrophage traits expression by cancer cells, M2-macrophage infiltration (MI) in tumor stroma and the immunohistochemical expression of biomarkers in cancer cells in relation to clinicopathologic data. Patients and Methods: We studied prospectively 122 patients with UBC, pathological stage pT1–pT4 treated with RC and pelvic lymph node dissection (PLND) during 2005–2011 at the Department of Urology, Linköping University Hospital. In the first study, we compared the results of preoperative PET/CT and conventional CT with the findings of postoperative histopathological evaluation of lymph nodes (LNs). In the second study we investigated the value of SNB technique for detecting pathological LNs during RC in patients with UBC. W also examined the significance of the primary tumor location in the bladder in predicting the site of LN metastases, and the prognostic significance of lympho-vascular invasion (LVI) and lymph node metastasis density (LNMD) on survival. In the third study, we investigate the clinical significance of macrophage infiltration (MI) in tumor stroma and macrophage-traits expression by tumor cells. In the fourth study, we investigate the cell cycle suppression proteins p53, p21, pRb, p16, p14 ARF as well as tumors proliferative protein Ki67 and DNA repair protein ERCC1 expression in cancer cells. The results were compared with clinical and pathological characteristics and outcome. Results: Prior to RC, PET/CT was used to detect LN metastasis in 54 patients. PET/CT had 41% sensitivity, 86% specificity, 58% PPV, and 76% NPV, whereas the corresponding figures for conventional CT were 41%, 89%, 64%, and 77%. SNB was performed during RC in 103 patients. A median number of 29 (range 7–68) nodes per patient were examined. SNs were detected in 83 out of 103 patients (81%). The sensitivity and specificity for detecting metastatic disease by SNB varied among LN stations, with average values of 67% -90%. LNMD or ≥8% and LVI were significantly related to shorter survival. In 103 patients, MI was high in 33% of cases, while moderate and low infiltration occurred in 42% and 25% of tumors respectively. Patients with tumors containing high and moderate compared to low MI had low rate of LN metastases (P=0.06) and improved survival (P=0.06), although not at significant level. The expression of different tumor suppression proteins was altered in 47-91% of the patients. There were no significant association between cancer specific survival (CSS) and any of the studied biomarkers. In case of altered p14ARF, ERCC1 or p21, CSS was low in case of low p53 immunostaining but increased in case of p53 accumulation, although not at a significant level, indicating a possible protective effect of p53 accumulation in these cases. Conclusion: PET/ CT provided no improvement over conventional CT in detection and localization of regional LN metastases in bladder cancer. It is possible to detect the SN but the technique is not a reliable for perioperative localization of LN metastases; however, LVI and LNMD at a cut-off level of 8% had significant prognostic values. MI in the tumor microenvironment but not CD163 expression in tumor cells seems to be synergistic with the immune response against urinary bladder cancer. Our results further indicate that altered p53 might have protective effect on survival in case of altered p14ARF, p21, or ERCC1 indicating an interaction between these biomarkers.
72

Response to neoadjuvant treatment in rectal cancer surgery

Loftås, Per January 2016 (has links)
Rectal cancer is one of the three most common malignancies in Sweden with an annual incidence of about 2000 cases. Current treatment consists of surgical resection of the rectum including the loco-regional lymph nodes in the mesorectum. In advanced cases, neoadjuvant chemo-radiotherapy (CRT) prior to the operative treatment reduces local recurrences and enables surgery. The neoadjuvant treatment can also eradicate the tumour completely, i.e. complete response. This research project was designed to investigate the effects of preoperative radiotherapy/ CRT and analyze methods to predict response to CRT. Study I investigated the expression of the FXYD-3 protein with immunohistochemistry in rectal cancer, with or without preoperative radiotherapy. The results from the total cohort showed that, strong FXYD-3 expression was correlated to infiltrative tumour growth (p = 0.02). In the radiotherapy group, strong FXYD-3 expression was related to an unfavourable prognosis (p = 0.02). Tumours with strong FXYD-3 expression had less tumour necrosis (p = 0.02) after radiotherapy. FXYD-3 expression in the primary tumour was increased compared to normal mucosa (p=0.008). We concluded that FXYD-3 expression was a prognostic factor in patients receiving preoperative radiotherapy for rectal cancer. Study II investigated FXYD-3 expression in tumours that developed local recurrences following surgery and compared this with expression in tumours that did not develop local recurrences. There was no difference in the expression of FXYD-3 between the group that developed local recurrences and the group that did not develop local recurrences. There was no difference in survival between those with strong or weak FXYD-3 expression. We concluded that this study could not confirm the findings from study 1 i.e. that FXYD-3 expression has prognostic significance in rectal cancer. Study III was a register-based study on the incidence and effects of complete response to neoadjuvant treatment. Eight per cent of the patients with adequate CRT to achieve complete response also had a complete histological response of the luminal tumor in the resected bowel. Sixteen per cent of that group had remaining lymph node metastases in the operative specimen. Chemotherapy together with radiotherapy doubled the chance of complete response in the luminal tumour. Patients with remaining lymph node metastases had a lower survival rate compared to those without. We concluded that residual nodal involvement after neoadjuvant treatment was an important factor for reduced survival after complete response in the luminal tumour. Study IV followed up the results from the previous study by re-evaluating magnetic resonance imaging (MRI)- images in patients with complete tumour response. Two experienced MRI radiologists performed blinded re-staging of post CRT MR- images from patients with complete response in the luminal tumour. One group with lymph node metastases and another one without were studied and the results compared with the pathology reports. The sensitivity, specificity, and positive and negative predicted values for correct staging of positive lymph nodes was 37%, 84%, 70% and 57%. The size of the largest lymph node (4.5 mm, p=0.04) seemed to indicate presence of a tumour positive lymph node. We concluded that MRI couldn’t correctly stage patients for lymph node metastases in patients with complete response to CRT in the luminal tumour.
73

Evaluation of strain circulation and the epidemiology of enteric fever caused

Karkey, Abhilasha January 2012 (has links)
Enteric fever caused by Salmonella enterica serovars Typhi and Paratyphi A are a major public health concern in Kathmandu. The aim of this thesis was to identify and assess the population most at risk by investigating epidemiologic trends of enteric fever within a subset population of Kathmandu. Therefore,the burden and incidence of enteric fever within the study population and the seasonal and gender distribution of enteric fever was assessed. Considerable burden of enteric fever, unrelated to population density, correlating with the seasonal fluctuations in rainfall was observed. This thesis also aimed to improve the understanding of enteric fever transmission by identifying probable transmission routes,hence various water and food samples were analysed and the extent of faecal contamination in them was determined. S. Typhi isolates were sequenced and genotyped and combined with GPS data to longitudinally study the local distribution and infer transmission of this human restricted bacterial pathogen. Extensive clustering of typhoid independent of population size and density and existence of an extensive range of genotypes within typhoid clusters including individual households with multiple cases was observed. These observations predict that indirect transmission had an overwhelming contribution for disease persistence, potentially through contaminated water. Consistent with this hypothesis, S. Typhi and S. Paratyphi A were detected in water supplies and it was observed that typhoid was spatially associated with public water sources and low elevation. A concurrent case-control study was also conducted which allowed for the determination of risk factors in the population at risk. These studies imply that resources should be allocated toward controlling the most important vectors of enteric fever, including food sold by vendors, chlorination of drinking water, construction of proper water distribution and sewage networks,vaccination campaigns and hygiene education.
74

Study of Platelet-mediated clumping adhesion phenotypes in Plasmodium falciparum malaria

Onyambu, Frank Gekara January 2015 (has links)
Platelet-mediated clumping of Plasmodium falciparum-infected erythrocytes (IEs) is a common property of field isolates associated with severe disease (Pain, Ferguson et al. 2001). Platelet receptors CD36 (Pain, Ferguson et al. 2001), P-Selectin (Wassmer, Taylor et al. 2008) and gC1qR (Biswas, Hafiz et al. 2007) mediate clumping. To characterize the molecular specificities of the clumping phenotype, I cloned clumping parasite line IT/C10 by limiting dilution. I characterized var gene expression in the IT/C10 clones using generic primers for the DBL tag region (Bull, Berriman et al. 2005). Clumping assays were conducted in the presence of specific reagents to delineate host factors hypothesized to contribute to development of the clumping phenotype. Finally, I conducted a clinical study with isolates from children with malaria in Kilifi, Kenya. This study shows that in parasite line IT/C10, platelet-mediated clumping is associated with Itvar30 suggesting a prominent role for the PfEMP-1 encoded by this var gene in development of platelet-mediated clumping. For IT/C10 parasites, platelet activation appears to be involved in platelet-mediated clumping. Platelet P-Selectin appears to mediate clumping using lectin-dependent interactions. To further elucidate the mechanisms that mediate clumping by host platelets, I have used a panel of platelet antagonists to delineate specific platelet activation pathways. Our results show that platelet activation plays an important role in platelet-mediated clumping. Finally, in this study, platelet-mediated clumping was associated with parasitaemia, but not with disease severity.
75

The role of Notch and GATA3 in postnatal and adult haematopoiesis

Duarte, Sara January 2011 (has links)
The role of Notch in cell fate determination and lineage restriction in the bone marrow (BM) is controversial in the field. Recent studies have convincingly shown that Notch is dispensable for haematopoietic stem cell (HSC) regulation in adult haematopoiesis (Maillard et al., 2008). In contrast, Notch signaling has been proposed to be of importance in the regulation of BM megakaryocyte progenitor differentiation, based on dominant negative genetic approaches, identifying a potentially distinct role for Notch in adult BM haematopoiesis (Mercher et al., 2008). Here, I found that by selectively ablating the gene coding the transcription factor recombination signal-binding protein J kappa (RBP-Jk), to which all canonical Notch signaling converges, canonical Notch signaling does not mediate HSC maintenance, neither in steady state nor in conditions of stress. Furthermore, I propose, in contrast with previous studies (Mercher et al., 2008), that canonical Notch signaling plays no role in myeloerythropoiesis cell lineage commitment in the BM. My data also show that key Notch target genes are suppressed by RBP-Jk, as their expression is unaffected in Notch1-deficient BM progenitors, while target genes are upregulated in Rbp-Jk-deleted megakaryocyte and erythroid progenitors. This establishes for the first time in mammalian cells in vivo, that Notch target genes are kept in a suppressed state by RBP-Jk, potentially restricting T cell commitment to the thymus and not to the BM, at the expense of myeloerythropoiesis. Notch signaling and GATA3 are two master regulators in T cell commitment (Han et al., 2002; Ho et al., 2009; Pui et al., 1999; Radtke et al., 1999; Zhu et al., 2004). However, although very well established as being involved in the thymic stages of T cell restriction, there is little evidence of Notch and GATA3 being involved in the migration of a thymus settling progenitor (TSP) from the BM to the thymus or in the establishment of the earliest thymic progenitor (ETP) in the thymus. From this thesis work, I conclude that Notch signaling is essential for the emergence of ETPs in the thymus in a NOTCH1-independent manner. Moreover, I demonstrate, as supported by a very recent published study (Hosoya et al., 2009), that GATA3 is important for the development of the earliest T cell progenitor. GATA1 and GATA2 mediate haematopoietic stem cell maintenance in the BM. GATA1 is required for erythropoiesis, megakaryocytes and eosinophils while GATA2 is important for the proliferation and survival of HSCs. In contrast, a role for GATA3 in the BM has never been established. By using a Gata3-conditional knockout mouse model, I demonstrate that GATA3 is dispensable for HSC maintenance in steady state and following active haematopoietic regeneration as well as for HSC self-renewal in the BM.
76

Enhancing the efficacy of viral vector blood-stage malaria vaccines

Forbes, Emily K. January 2011 (has links)
Replication-deficient adenovirus (Ad) and modified vaccinia virus Ankara (MVA) vectors expressing single Plasmodium falciparum antigens can induce potent T cell and antibody responses and have entered clinical testing using a heterologous prime-boost immunisation approach (Ad_MVA). This thesis describes a number of pre-clinical approaches aimed at enhancing the efficacy of these viral vectored vaccines targeting the blood-stage of malaria. First, the development of a highly efficacious malaria vaccine is likely to require a multi-antigen and/or multi-stage subunit vaccine. The utility of an Ad_MVA immunisation regime combining vaccines expressing the 42kDa C-terminus of the blood- stage antigen merozoite surface protein 1 (MSP142) and the pre-erythrocytic antigen circumsporozoite protein (CSP) in the P. yoelii mouse model was investigated. It was found that vaccine co- administration leads to maintained antibody responses and efficacy against blood-stage infection, but reduced secondary CD8+ T cell responses and efficacy against liver-stage infection. CD8+ T cell interference can be minimised by co-administering the MVA vaccines at separate sites, resulting in enhanced liver-stage efficacy. The mechanisms of CD8+ T cell interference were explored. Second, Ad_MVA regimes expressing blood-stage antigens that can protect against P. chabaudi and P. yoelii blood-stage infection were tested against P. berghei, but did not confer protection. Similarly, IgG from rabbits immunised against P. falciparum MSP1 (PfMSP1) could not protect mice from a chimeric P. berghei parasite expressing PfMSP1. Third, two molecular adjuvants, the C4bp α-chain oligomerisation domain (IMX108/313) and the Fc fragment of murine IgG2a, were tested for their ability to enhance immunogenicity of recombinant adenoviruses when fused at the C-terminus of a blood-stage antigen. IMX108/313 was found to adjuvant T cell responses of small (< 80kDa) antigens and this was associated with antigen oligomerisation. However, the Fc fragment did not adjuvant responses. Finally, it was found that using a strong early promoter to drive antigen expression enhances the immunogenicity of single administration MVA vaccines, but that this did not enhance post-boost immunogenicity in an Ad_MVA regime.
77

Probing the molecular basis of melanopsin induced light sensitivity

Vachtsevanos, Athanasios January 2012 (has links)
It has been demonstrated that retinal photoreception among mammals extends beyond rods and cones to include a small number of intrinsically photosensitive retinal ganglion cells (pRGCs), which are capable of responding to light due to expression of the melanopsin (OPN4) photopigment. OPN4 may have therapeutic potential if ectopically expressed in the degenerate retina in cases where photoreceptors are lost, but the other molecules involved in this light induced transduction cascade are less well characterized. Therefore I sought to probe further the mechanism of OPN4 mediated light sensitivity by siRNA mediated knock down of specific molecules in two mice models in which complete loss of rods and cones renders them almost exclusively dependent on the OPN4 pathway for light sensitivity. I generated siRNA probes against the long transcript variant of murine Opn4 mRNA and first tested these probes on the murine Neuro2A (N2a) cell line, before assessing effects in C3H/HeN rd and rodless/coneless rd/rd cl mice. siRNA was injected intravitreally into one eye and pupillometry was assessed, combined with molecular analyses at various timepoints. Reverse transcription polymerase chain reaction (RT-PCR) analysis in N2a cells confirmed Opn4 knockdown and immunolabelling techniques identified >85% silencing with siRNA. Pupil responses in the rd and rd/rd cl mice were inhibited by the siRNA injections in vivo which confirmed the functional effect of Opn4 silencing detected by molecular analysis. I therefore present a novel reproducible in vivo model in which siRNA induced silencing of the melanopsin pathway can be assessed by pupillometry and compared to levels of mRNA and protein at specific timepoints. Probes against other putative candidate genes, such as TRPC3, may unravel the molecular interactions of this pathway. This may help in future to induce light sensitivity in other retinal neurons in patients who are completely blind from photoreceptor loss.
78

Verifiering av P-LDL-kolesterol på Beckman Coulter AU680 / Verification of P-LDL-cholesterol on Beckman Coulter AU680

Oliveira Ivarsson, Martin January 2019 (has links)
Kolesterol transporteras i blodet med hjälp av lipoproteinpartiklar. Höga nivåer av low-density lipoprotein (LDL)-kolesterol i blodet är en riskfaktor för kardiovaskulär sjukdom. Koncentrationen av LDL-kolesterol kan beräknas med hjälp av Friedewalds formel men det finns även metoder där LDL-kolesterol kan analyseras direkt. Syftet med arbetet var att verifiera metoden direkt LDL-kolesterol på analysinstrumentet Beckman Coulter AU680. Metodens inomserie- och totalimprecision analyserades. Två korrelationsstudier utfördes mellan direkt LDL-kolesterol och beräknat LDL-kolesterol, en med 43 patientprover med triglycerider &lt; 4,5 mmol/L och en med 11 patientprover med triglycerider &gt; 4,5 mmol/L. Friedewalds formel ska egentligen inte användas vid triglycerider &gt; 4,5 mmol/L, men i detta fall användes formeln ändå för att utvärdera eventuella skillnader mellan metodernas resultat vid höga triglyceridkoncentrationer. Vid analys av metodens inomserieimprecision blev variationskoefficienten (CV) omkring 0,5 % vid analys av både den låga kontrollen (A1) och den höga kontrollen (A2). CV för totalimprecisionen blev 1,21 % vid analys av A1 och 1,11 % vid analys av A2. Korrelationsstudierna visade ett linjärt samband mellan metoderna men den direkta metoden gav något högre resultat vid lägre koncentrationer och något lägre resultat vid högre koncentrationer jämfört med beräknat LDL-kolesterol. Vid triglycerider &gt; 4,5 mmol/L gav den direkta metoden betydligt högre resultat än beräknat LDL-kolesterol. Slutsatsen blev att metoden hade god precision. Överensstämmelsen mellan metodernas resultat var relativt bra för proverna med triglycerider &lt; 4,5 mmol/L. Vid triglycerider &gt; 4,5 mmol/L var differensen mellan metoderna stor, troligtvis på grund av falskt för låga resultat från beräknat LDL-kolesterol. / Cholesterol is transported in the blood by lipoproteins. High levels of low-density lipoprotein (LDL)-cholesterol in the blood is a risk factor for cardiovascular disease. The concentration of LDL-cholesterol can be calculated using the Friedewald formula but there are also methods that measure LDL-cholesterol directly. The aim of this study was to verify the method P-LDL-cholesterol on a Beckman Coulter AU680 analyzer. Within-run imprecision and total imprecision were analyzed. The correlation between direct LDL-cholesterol and calculated LDL-cholesterol was examined using 43 patient samples with triglyceride levels &lt; 4,5 mmol/L and 11 patient samples with triglyceride levels &gt; 4,5 mmol/L. The Friedewald formula is not supposed to be used on triglyceride levels &gt; 4,5 mmol/L, but in this case the formula was used anyway to evaluate differences between the methods at high triglyceride concentrations. The coefficient of variation (CV) for the within-run imprecision was about 0,5 %, both for the low control (A1) and the high control (A2). Total imprecision had a CV of 1,21 % for A1 and 1,11 % for A2. There was a linear relationship between the methods, but the direct method gave slightly higher results at low concentrations and slightly lower results at high concentrations compared to calculated LDL-cholesterol. At triglyceride levels &gt; 4,5 mmol/L the results from the direct method was considerably higher than calculated LDL-cholesterol. The conclusion is that the precision of the method was good. The correlation between the results from direct LDL-cholesterol and calculated LDL-cholesterol was relatively high for samples with triglyceride levels &lt; 4,5 mmol/L. At triglyceride levels &gt; 4,5 mmol/L there was a big difference between the methods, probably because of falsely low results from calculated LDL-cholesterol.
79

Implementação do biobanco e do laboratório central e validação do protocolo de laboratório do ELSA-Brasil / Implementation of the biobank and the central laboratory and validation of laboratory protocol ELSA-Brazil

Fedeli, Ligia Maria Giongo 06 May 2013 (has links)
Introdução: O Estudo Longitudinal de Saúde do Adulto é um estudo de coorte multicêntrico com o objetivo de identificar os fatores de risco associados ao diabetes tipo 2 e à doença cardiovascular na população brasileira. Nosso principal objetivo é explicar a concepção e implementação das rotinas do laboratório central e biobanco do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil); destacando as forças e limitações do protocolo. O segundo objetivo é descrever os pré-testes usados para validar o protocolo de antes do início do estudo. Métodos: O estudo optou pela centralização dos exames em um laboratório central no Hospital Universitário da Universidade de São Paulo (USP), Com base em dados recentes que confirma a estabilidade da glicose em amostras congeladas, até os testes de glicose no sangue foram centralizadas. Porém o processamento das amostras foi realizado nos laboratórios locais o que reduziu os custos do transporte das amostras para o laboratório central. A estratégia implicou na necessidade de implementação de equipes nos laboratórios em cada Centro de Investigação para coletar e processar as amostras antes do transporte. O estudo incluiu exames para a avaliação do metabolismo da glicose, resistência à insulina, perfil lipídico, eletrólitos, ácido úrico, hormônios da tireóide, função hepática e contagem total de células do sangue. Além disso, as amostras de DNA, urina plasma, e de soro foram colhidas e Além desses exames, o estudo também extraiu DNA de leucócitos, colheu e estocou amostras de urina, plasma e soro. Para garantir a homogeneidade do protocolo todos os membros das equipes locais passaram por treinamento e certificação centralizado, com visitas cruzadas entre os centros durante o campo para controle de qualidade. Resultados: A opção por um laboratório central garantiu a uniformidade da metodologia utilizada para a realização dos exames, evitando as variações inevitáveis entre laboratórios. Durante 26 meses, cerca de 375.000 testes foram realizados no laboratório central. Não houve perda de amostras biológicas durante o estudo. A implementação do biobanco usando palhetas armazenados em repositórios de nitrogênio foi realizada sem problemas importantes desde 2008 até agora. Conclusão: O ELSA-Brasil mostrou a exequibilidade de exames multicêntricos no Brasil com todos os exames realizados em um laboratório central, de uma maneira custo-efetiva. A logística de armazenamento de amostras biológicas foi feito com custos aceitáveis e de qualidade, sendo um modelo para estudos futuros / Background: The Longitudinal Study of Adult Health is a multicenter cohort study aimed to identify risk factors associated with type 2 diabetes and cardiovascular disease in Brazilian population. Our main objective is to explain the conception and implementation of the routines of the central laboratory and biobank of the Longitudinal Study of Adult Health (ELSA-Brasil) highlighting the strength and the limitations of the protocol The second objective is to describe the pre-tests used to validate the protocol before the start of the study. Methods: The study made an option to centralize the exams in one central laboratory at the University Hospital, São Paulo University (\"USP\"). Based on recent data that confirms the stability of glucose in freeze samples, even blood glucose tests were centralized. However, biological samples were processed in the local laboratories, reducing the weight of the material to be transported, and diminishing costs of transportation to the central lab. Especially trained local teams collected and processed biological samples before transportation. The study included tests for glucose metabolism, insulin resistance, lipid profile, electrolytes, uric acid, thyroid hormones, hepatic function, and total blood cell count. In addition, DNA, urine, plasma and serum samples were collected and stored. In order to guarantee protocol homogeneity, all team members underwent centralized training and certification, and cross-visits in each research center were done. Results: The choice of a central laboratory assured uniformity of the methodology used for the exams, avoiding the variations between laboratories During 26 months, approximately 375,000 tests were done in the central- laboratory. There was no loss of biological samples during the study. The implementation of the biobank using straws stored in nitrogen repositories was performed without important problems since 2008 until now. Conclusion: The ELSA-Brazil showed the feasibility of a multicenter study in Brazil with all the analyses performed in a central laboratory, in a cost-effective way. The logistic of storage of biological samples was done with acceptable costs and quality being a model for future studies
80

Implementação do biobanco e do laboratório central e validação do protocolo de laboratório do ELSA-Brasil / Implementation of the biobank and the central laboratory and validation of laboratory protocol ELSA-Brazil

Ligia Maria Giongo Fedeli 06 May 2013 (has links)
Introdução: O Estudo Longitudinal de Saúde do Adulto é um estudo de coorte multicêntrico com o objetivo de identificar os fatores de risco associados ao diabetes tipo 2 e à doença cardiovascular na população brasileira. Nosso principal objetivo é explicar a concepção e implementação das rotinas do laboratório central e biobanco do Estudo Longitudinal de Saúde do Adulto (ELSA-Brasil); destacando as forças e limitações do protocolo. O segundo objetivo é descrever os pré-testes usados para validar o protocolo de antes do início do estudo. Métodos: O estudo optou pela centralização dos exames em um laboratório central no Hospital Universitário da Universidade de São Paulo (USP), Com base em dados recentes que confirma a estabilidade da glicose em amostras congeladas, até os testes de glicose no sangue foram centralizadas. Porém o processamento das amostras foi realizado nos laboratórios locais o que reduziu os custos do transporte das amostras para o laboratório central. A estratégia implicou na necessidade de implementação de equipes nos laboratórios em cada Centro de Investigação para coletar e processar as amostras antes do transporte. O estudo incluiu exames para a avaliação do metabolismo da glicose, resistência à insulina, perfil lipídico, eletrólitos, ácido úrico, hormônios da tireóide, função hepática e contagem total de células do sangue. Além disso, as amostras de DNA, urina plasma, e de soro foram colhidas e Além desses exames, o estudo também extraiu DNA de leucócitos, colheu e estocou amostras de urina, plasma e soro. Para garantir a homogeneidade do protocolo todos os membros das equipes locais passaram por treinamento e certificação centralizado, com visitas cruzadas entre os centros durante o campo para controle de qualidade. Resultados: A opção por um laboratório central garantiu a uniformidade da metodologia utilizada para a realização dos exames, evitando as variações inevitáveis entre laboratórios. Durante 26 meses, cerca de 375.000 testes foram realizados no laboratório central. Não houve perda de amostras biológicas durante o estudo. A implementação do biobanco usando palhetas armazenados em repositórios de nitrogênio foi realizada sem problemas importantes desde 2008 até agora. Conclusão: O ELSA-Brasil mostrou a exequibilidade de exames multicêntricos no Brasil com todos os exames realizados em um laboratório central, de uma maneira custo-efetiva. A logística de armazenamento de amostras biológicas foi feito com custos aceitáveis e de qualidade, sendo um modelo para estudos futuros / Background: The Longitudinal Study of Adult Health is a multicenter cohort study aimed to identify risk factors associated with type 2 diabetes and cardiovascular disease in Brazilian population. Our main objective is to explain the conception and implementation of the routines of the central laboratory and biobank of the Longitudinal Study of Adult Health (ELSA-Brasil) highlighting the strength and the limitations of the protocol The second objective is to describe the pre-tests used to validate the protocol before the start of the study. Methods: The study made an option to centralize the exams in one central laboratory at the University Hospital, São Paulo University (\"USP\"). Based on recent data that confirms the stability of glucose in freeze samples, even blood glucose tests were centralized. However, biological samples were processed in the local laboratories, reducing the weight of the material to be transported, and diminishing costs of transportation to the central lab. Especially trained local teams collected and processed biological samples before transportation. The study included tests for glucose metabolism, insulin resistance, lipid profile, electrolytes, uric acid, thyroid hormones, hepatic function, and total blood cell count. In addition, DNA, urine, plasma and serum samples were collected and stored. In order to guarantee protocol homogeneity, all team members underwent centralized training and certification, and cross-visits in each research center were done. Results: The choice of a central laboratory assured uniformity of the methodology used for the exams, avoiding the variations between laboratories During 26 months, approximately 375,000 tests were done in the central- laboratory. There was no loss of biological samples during the study. The implementation of the biobank using straws stored in nitrogen repositories was performed without important problems since 2008 until now. Conclusion: The ELSA-Brazil showed the feasibility of a multicenter study in Brazil with all the analyses performed in a central laboratory, in a cost-effective way. The logistic of storage of biological samples was done with acceptable costs and quality being a model for future studies

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