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Comparação entre a estratificação clínica e a cintilografia de perfusão miocárdica como preditores de eventos cardiovasculares em candidatos a transplante renal / Comparison between clinical stratification and myocardial perfusion scintigraphy as a predictor of cardiovascular events in kidney transplant candidatesRodolfo Leite Arantes 18 September 2009 (has links)
A doença cardiovascular (DCV) é uma condição clínica comum entre pacientes (pcts) portadores de doença renal crônica (DRC) e é causa de eventos fatais observados peri transplante renal (TX). A melhor estratégia de avaliação cardiovascular em candidatos a transplante (CTR) ainda é controversa.Ignora-se se todos os pacientes devem ser submetidos a testes não-invasivos/invasivos ou se estes devem ser reservados aqueles com determinadas características clínicas, como população geral. O objetivo deste estudo foi comparar a estratificação de risco baseada em método nãoinvasivo de detecção de doença coronária com dois métodos de estratificação clínica de risco cardiovascular preconizados pela American Society of Transplantation (AST) e European Renal Association (ERA). A AST subdivide os pcts em : alto risco (idade maior ou igual a 50 anos e/ou diabete e/ou DCV clínica) e baixo risco (os demais). A ERA subdivide em: alto risco (DCV clínica), risco intermediário (diabéticos e/ou idade maior ou igual a 50 anos) e baixo risco (os demais). Nós estudamos 386 pcts com DRC em diálise enviados ao nosso serviço para avaliação cardiovascular antes da inclusão na lista de espera de TX. Foram estratificados quanto ao risco de eventos de acordo com os dois algoritmos acima e alterações na cintilografia de perfusão miocárdica (SPECT-MIBI) com dipiridamol e acompanhados até a morte, TX ou ocorrência de eventos. A estratificação clínica (RR:1,8 [IC95% 1,3 2,6- P<0,0001] e o SPECT-MIBI (RR:1,5 [IC95% 1,2-1,9-P=0,002] identificaram os pcts de maior risco de eventos cardiovasculares . Apenas os pcts ASTalto risco (RR1,4 [IC95%1,1-1,8-P=0,002] e ERA médio risco com SPECTMIBI alterado (RR:1,7 [IC95% 1,2-2,3-P=0,003] tiveram maior incidência de eventos. Os pcts de baixo risco pelos dois algorítmos de estratificação clínica (P=0,50) e do sistema ERA alto risco (RR:1,1 [IC95% 0,8-1,5-P=0,41], não se beneficiaram dos resultados do estudo não-invasivo. Concluímos que os estudos não-invasivos não devem ser utilizados em todos os CTR mas devem ser reservados aos pcts previamente identificados pela estratificação clínica de risco. Esses resultados permitem uma abordagem mais racional da avaliação pré- TX com melhor uso dos recursos econômicos escassos. / Cardiovascular (CV) disease is a common condition in chronic kidney disease (CKD) patients and is the leading cause of fatal events during and after renal transplantation. The best strategy for CV evaluation and coronary risk stratification in renal transplant candidates remains controversial. Moreover, there is no consensus regarding the best strategy for detection of coronary artery disease (CAD). We still do not know if all patients should be evaluated by noninvasive testing or if this approach should be restricted to individuals with clinical evidence of CAD, as in the general population. The objective of this study was to compare CV risk stratification based on nonivasive testing for CAD with two clinical stratification methods as advanced by The American Society of Transplantation (AST) and by The European Renal Association (ERA), respectively. The AST divides patients in high risk (age50 years and/or diabetes and/or CV disease) and low risk (all others).The ERA divides : high risk (CV disease), intermediate risk (age 50 years and/or diabetes), and low risk (as above). We studied 386 CKD patients treated by hemodyalisis, to CV evaluation before being admitted to the renal transplant waiting list. All patients were stratified for the risk of future major cardiovascular events (MACE) using the clinical algorithms and also by myocardial scintigraphy (SPECT-MIBI) with dipyridamol and followedup until death, transplant or MACE. Clinical algorithms (RR:1,8 [IC95% 1,3 2,6-P<0,0001] and SPECT-MIBI(RR:1,5 [IC95% 1,2-1,9-P=0,002] identified patients at increased risk of events. The combined use of clinical stratification followed by SPECT showed that the only patients that would benefit from SPECT risk stratification were those belonging the AST-high risk (RR1,4 [IC95%1,1-1,8-P=0,002] and ERA-intermediate risk groups (RR:1,7 [IC95% 1,2-2,3-P=0,003]. In all other groups :ERA-high-risk (RR:1,1[IC95% 0,8-1,5- P=0,41] and ERA and AST-low-risk (P=0,50) SPECT did not add to the probability of events defined by clinical stratification alone. We conclude that SPECT should not be applied to all renal transplant candidates but should be restricted to those considered at a category of risk as defined by clinical algorithms. These results delineate a more rational approach to risk stratification in renal transplant candidates with a better utilization of economical resources.
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Description, Classification, and Prediction of Dengue Illnesses in a Thai Pediatric Cohort: A DissertationPotts, James A. 12 May 2010 (has links)
Dengue fever (DF) and dengue hemorrhagic fever (DHF) are emerging infectious diseases which are endemic in many regions of the globe, many of which are resource-poor areas. DHF and DF impose a severe economic health burden in tropical and subtropical areas. Dengue virus causes an acute febrile illness that can be a self-limited febrile illness, as seen in most cases of DF, or a life-threatening illness with plasma leakage and shock, as seen in cases of DHF. A systematic review of the literature revealed gaps in the knowledge base of clinical laboratory findings of dengue illness with regards to longitudinal dynamics and classification and predictive modeling of disease severity. The objective of this thesis was to investigate the utility of clinical laboratory variables for classification and prediction of disease outcomes.
The data used in this investigation was derived from a prospective study of Thai children presenting to either of two study hospitals within 72 hours of onset of an acute febrile illness. Systematic data collection, including clinical laboratory parameters, and routine clinical management continued each day until 24 hours after the fever had subsided. A final diagnosis of DHF, DF, or other febrile illness (OFI) was assigned by an expert physician after chart review.
The first research objective of this study was to describe the temporal dynamics of clinical laboratory parameters among subjects with DHF, DF, or OFI. Data were analyzed using lowess curves and population-average models. Quadratic functions of clinical variables over time were established and demonstrated significantly divergent patterns between the various diagnostic groups.
The second research objective was to establish and validate tools for classification of illness severity using easily obtained clinical laboratory measures. Bivariate logistic regression models were established using data from one hospital in an urban area of Thailand as a training data set and validated with a second data set from a hospital in a rural area of Thailand. The validated models maintained a high sensitivity and specificity in distinguishing severe dengue illnesses without using the hallmark indicators of plasma leakage.
The third research objective used classification and regression tree (CART) analysis to established diagnostic decisions trees using data obtained on the day of study enrollment, within the first 3 days of acute illness. Decision trees with high sensitivity were established for severe dengue defined either as: 1) DHF with evidence of shock (dengue shock syndrome, DSS); or 2) DSS or dengue with significant pleural effusion.
This study expands existing knowledge of the potential utility of clinical laboratory variables during different phases of dengue illness. The application of the results of these studies should lead to promising opportunities in the fields of epidemiological research and disease surveillance to reduce the health burden, and improve the clinical management, of dengue illness. Future directions involve application of these algorithms to different study populations and age groups. Additionally, other analytical techniques, such as those involving CART analysis, can be explored with these data.
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Prediktivni faktori nastanka akutne renalne insuficijencije na odeljenju intenzivnog lečenja / Predictive factors of acute renal insufficiency occurrence in intensive care unitUvelin Arsen 04 March 2015 (has links)
<p>Uvod: Učestalost akutne renalne insuficijencije, odnosno akutnog bubrežnog oštećenja u jedinicama intenzivnog lečenja se kreće od 36 do 66 %. Akutno bubrežno oštećenje povišava smrtnost, trajanje hospitalizacije i ukupne troškove lečenja. Ranije prepoznavanje prediktivnih faktora za nastanak akutnog bubrežnog oštećenja može da ima značajan uticaj na pravovremeno započinjanje terapijskih mera i smanjivanje mortaliteta kod kritično obolelih. Cilj istraživanja: Utvrditi incidencu akutnog bubrežnog oštećenja na Odeljenju reanimacije Urgentnog centra Kliničkog centra Vojvodine tokom 2011.godine, učestalost sepse kao etiološkog faktora i značajne prediktivne faktore za nastanak akutnog bubrežnog oštećenja koji se javljaju u toku prvih 24 časa lečenja na odeljenju intenzivnog lečenja. Metodologija: Retrospektivno-prospektivna opservaciona studija uključila je uzorak od 251 ispitanika koji su se lečili na dva odeljenja intenzivnog lečenja u Kliničkom centru Vojvodine tokom 2010, 2011, i prvih 6 meseci 2012.godine. Iz medicinske dokumentacije (istorije bolesti, dnevne terapijske liste i liste vitalnih i laboratorijskih parametara) za svakog ispitanika je verifikovano prisutvo ili odsustvo potencijalnog prediktivnog faktora. Zatim je zabeležena pojava akutnog bubrežnog oštećenja prema RIFLE kriterijumima. Statistička analiza je izvršena pomoću statističkog paketa IBM SPSS 20 Statistics. Podaci su predstavljeni tabelarno i grafički, a statistička značajnost određivana je na nivou p< 0,05. Prikupljeni podaci su obrađeni standardnim statističkim testovima. Za izvođenje modela predviđanja primenjena je multivarijatna logistička regresija. Određene su granične tačke na osnovu ROC analize za dobijene značajne prediktore iz multivarijacione logističke regresije i izračunati su pridruženi bodovi koji bi činili skoring sistem za utvrđivanje rizika od nastanka akutnog bubrežnog oštećenja. Rezultati: Incidenca akutnog bubrežnog oštećenja na Odeljenju reanimacije Urgentnog centra Kliničkog centra Vojvodine u Novom Sadu kod bolesnika koji su hospitalizovani najkraće 48 časova u toku 2011.godine je 32 %. Rezna tačka (cut off value) zapremine provocirane diureze jedan čas nakon intravenskog davanja bolusa furosemida od 0,165 ml/kg telesne mase/čas/po miligramu datog furosemida ima najvišu senzitivnost (82,3 %) i specifičnost (67,5 %) u diferenciranju bolesnika koji će razviti ABO. Konačni model predloženog skoring sistema sa ulogom predikcije nastanka ABO nakon 24 časa lečenja bolesnika na odeljenju intenzivnog lečenja sadrži sledeće varijable: starost višu od 53 godine, vrednost APACHE skora višu od 16, prosečnu diurezu prvih 6 časova hospitalizacije nižu od 0,875 ml/kg/h, primenu vazopresora, kalijemiju višu od 4,5 mmol/l i koncentraciju laktata iznad 2 mmol/l. Zaključak: Incidenca akutnog bubrežnog oštećenja na Odeljenju reanimacije Urgentnog centra Kliničkog centra Vojvodine je slična literaturnim podacima. Bolesnici koji su stariji, imaju više vrednosti APACHE II skora, nižu prosečnu zapreminu diureze u toku prvih 6 časova po prijemu, koji primaju vazopresorne medikamente, imaju višu koncentraciju kalijuma i više koncentracije laktata u toku prvih 24 časa lečenja imaju veću šansu da razviju akutno bubrežno oštećenje.</p> / <p>Introduction: The incidence of acute renal insufficiency (acute kidney injury) in intensive care unit is between 36 and 66 %. Acute kidney injury is responsible for higher mortality, longer hospitalization and higher costs. Earlier recognition of acute kidney injury predictive factors could have important impact on right timing of therapeutic measures and lower mortality in critically ill patients. Aims: investigate the incidence of acute kidney injury during 2011. in patients who are hospitalized at Department of reanimation of Emergency centre, Clinical centre of Vojvodina, incidence of acute kidney injury caused by sepsis in the same period and detect acute kidney injury occurrence predicitive factors Methodology: This retrospective-prospective observational study investigated 251 critically ill patients-study subjects who were treated at two intensive care departments in Clinical centre of Vojvodina during 2010, 2011 and first six months of 2012. Potential predictive factors were identified out of medical records (patient history, daily therapeutic lists, vital parameters and laboratory values lists); the occurrence of acute kidney injury was noted according to RIFLE criteria. IBM SPSS version 20 was used for statistical analysis, standard statystical test were applied. The results were presented in tables and graphs, statystical significance was set at p value of less than 0,05. Multivariate logistic regression model was used for potential predictive factors. Statystically important factors were identified and their best sensitivity and specificity cut-off values were found using ROC curve analysis.; These cut-off values were used for creating a scoring system that determines the risk for acute kidney injury occurrence. Results: The incidence of acute kidney injury at Department of reanimation, Clinical centre of Vojvodina in patients who were hospitalized at least 48 hours was 32 % during 2011. The cut off value of provoked hourly urine output during first hour after furosemide intravenous bolus of 0.165 ml/kg body weight/h/miligram of administered furosemide has the highest sensitivity (82.3 %) and specifity (67.5 %) in differentiation of patients who would develop acute kidney injury and those who would not. The final suggested model of scoring system with the role of acute kidney injury prediction after 24 hours of treatment contains the next variables: age higher than 53 years, APACHE II score higher than 16, avarage hourly urine output during first 6 hours after ICU admission less than 0,875 ml/kg BW/h, vasopressor medication administration, blood potassium concentration higher than 4,5 mmol/l, lactates higher than 2 mmol/l after 24 hours of treatment. Conclusion: The incidence of acute kidney injury at Department of reanimation of Emergency centre, Clinical centre of Vojvodina is similar to world literature references. Critically ill patients who are more likely to develop acute kidney injury are older, have higher APACHE II score values, lower avarage urine output in the first 6 hours after ICU admission, are administered vasopressor medication, have higher blood potassium and lactate concentration in the first 24 hours of their treatment.</p>
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Metamemory and prospective memory in Parkinson's diseaseSmith, Sarah J., Souchay, C., Moulin, C.J.A. January 2011 (has links)
No / Metamemory is integral for strategizing about memory intentions. This study investigated the prospective memory (PM) deficit in Parkinson's disease (PD) from a metamemory viewpoint, with the aim of examining whether metamemory deficits might contribute to PM deficits in PD. METHOD: Sixteen patients with PD and 16 healthy older adult controls completed a time-based PM task (initiating a key press at two specified times during an ongoing task), and an event-based PM task (initiating a key press in response to animal words during an ongoing task). To measure metamemory participants were asked to predict and postdict their memory performance before and after completing the tasks, as well as complete a self-report questionnaire regarding their everyday memory function. RESULTS: The PD group had no impairment, relative to controls, on the event-based task, but had prospective (initiating the key press) and retrospective (recalling the instructions) impairments on the time-based task. The PD group also had metamemory impairments on the time-based task; they were inaccurate at predicting their performance before doing the task but, became accurate when making postdictions. This suggests impaired metamemory knowledge but preserved metamemory monitoring. There were no group differences regarding PD patients' self-reported PM performance on the questionnaire. CONCLUSIONS: These results reinforce previous findings that PM impairments in PD are dependent on task type. Several accounts of PM failures in time-based tasks are presented, in particular, ways in which mnemonic and metacognitive deficits may contribute to the difficulties observed on the time-based task.
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Development and validation of a decision tree early warning score based on routine laboratory test results for the discrimination of hospital mortality in emergency medical admissionsJarvis, S.W., Kovacs, C., Badriyah, T., Briggs, J., Mohammed, Mohammed A., Meredith, P., Schmidt, P.E., Featherstone, P.I., Prytherch, D.R., Smith, G.B. 31 May 2013 (has links)
No / To build an early warning score (EWS) based exclusively on routinely undertaken laboratory tests that might provide early discrimination of in-hospital death and could be easily implemented on paper. Using a database of combined haematology and biochemistry results for 86,472 discharged adult patients for whom the admission specialty was Medicine, we used decision tree (DT) analysis to generate a laboratory decision tree early warning score (LDT-EWS) for each gender. LDT-EWS was developed for a single set (n=3496) (Q1) and validated in 22 other discrete sets each of three months long (Q2, Q3...Q23) (total n=82,976; range of n=3428 to 4093) by testing its ability to discriminate in-hospital death using the area under the receiver-operating characteristic (AUROC) curve. The data generated slightly different models for male and female patients. The ranges of AUROC values (95% CI) for LDT-EWS with in-hospital death as the outcome for the validation sets Q2-Q23 were: 0.755 (0.727-0.783) (Q16) to 0.801 (0.776-0.826) [all patients combined, n=82,976]; 0.744 (0.704-0.784, Q16) to 0.824 (0.792-0.856, Q2) [39,591 males]; and 0.742 (0.707-0.777, Q10) to 0.826 (0.796-0.856, Q12) [43,385 females]. CONCLUSIONS: This study provides evidence that the results of commonly measured laboratory tests collected soon after hospital admission can be represented in a simple, paper-based EWS (LDT-EWS) to discriminate in-hospital mortality. We hypothesise that, with appropriate modification, it might be possible to extend the use of LDT-EWS throughout the patient's hospital stay.
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Prognostički faktori za povratak na posao kod bolesnika operisanih zbog lumbalne diskus hernije / Prognostic factors for return to work after lumbar discectomyPapić Monika 21 September 2016 (has links)
<p>Povratak na posao nakon operacije lumbalne diskus hernije determinisan je funkcionalnim stanjem, prisustvom i stepenom tegoba od strane lumbosakralne kičme, zahtevima na radnom mestu bolesnika ali i psihosocijalnim faktorima, koji pri oceni radne sposobnosti zaposlnih zahtevaju individualni pristup. Grupa pacijenata koja se neće vratiti na posao može biti identifikovana putem prognostičkog modela. Cilj ove studije je definisanje prognostičkog modela za povratak na posao bolesnika operisanih zbog lumbalne diskus hernije kao i identifikacija najznačajnijih faktora rizika odgovornih za loš ishod operativnog lečenja, posmatrano kroz prizmu povratka na posao. Istraživanje je prospektivna studija koja je obuhvatila ukupno 200 ispitanika, koji su operisani zbog lumbalne diskus hernije na jednom nivou i praćeni su u vremenskom period do 12 meseci nakon operativnog lečenja. U statističku ananlizu je ušlo 153 bolesnika, koji su ispunili kriterijume selekcije ispitanika studije. Nakon određivanja značaja posmatranih bioloških, profesionalnih i psihosocijalnih faktora rizika za povratak na posao, kreirani su i evaluirani prognostički modeli bazirani na svim i na odabranim atributima desetostrukom kros-validacijom: stablo odlučivanja (DT), model višeslojnih perceptrona (MLP) i model potpornih vektora (SVM). Za predviđanje povratka na posao najveću tačnost, specifičnost i senzitivnost za odabrane atribute postiže model potpornih - podržavajućih vektora (SVM). Najbolju intuitivnu i praktičnu vrednost za predviđanje povratka na posao pruža model stabla odluka (DT). Identifikacijom najznačajnijih faktora rizika za nepovoljan ishod povratka na posao omogućeno je preventivno delovanje na iste, u cilju smanjenja broja pacijenata sa umanjenjem radne sposobnosti i invaliditeta.</p> / <p>Return to work after lumbar discectomy is determinated by functional status, presence and degree of discomfort in the lumbosacral spine, the requirements in the workplace of patients and psychosocial factors that in the assessment of working capabilities require an individual approach. Groups of patients which don’t return to work after surgery could be identified by predictive model. The aim of this study is to define prognostic model to return to work patients after lumbar discectomy, as well as the identification major risk factors responsible for the poor outcome of operative treatment viewed through the prism of returning to work. This prospective study included a total of 200 patients, who underwent surgery for lumbar disc herniation on one level and were followed up in period of 12 months following surgery. The statistical analysis included 153 patients who fulfilled all selection criteria of the study subjects. After determining significance of the observed biological, professional and psychosocial risk factors for return to work, prognostic models were designed and evaluated based on all and selected attributes by tenfold cross-validation: decision tree (DT) model of multilayer perception (MLP) model and support vector (SVM). For the prediction of return to work best accuracy, specificity and sensitivity for selected attributes, is achieved by supporting vector model (SVM). The decision tree model (DT) provides the best intuitive and practical value for predicting return to work. By identifying the most important risk factors for adverse outcome for return to work it is made possible for preventive actions, to reduce the number of patients with reduced work ability and disability.</p>
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Metode istraživanja podataka u evaluaciji intra-hospitalnog ishoda obolelih od akutnog infarkta miokarda lečenih primarnom perkutanom koronarnom intervencijom / Data mining methods in evaluation of intra-hospital outcome of patients with acute myocardial infarction treated with primary percutaneous coronary interventionSladojević Miroslava 28 September 2016 (has links)
<p>Uvod: Stratifikacija rizika je postala integralna komponenta savremenog pristupa tretmanu u kliničkoj praksi. Danas se u dijagnostici i lečenju akutnog infarkta miokarda (AIM) koriste različiti skorovi rizika kao prognostički instrumenti za kratkoročan i dugoročan ishod bolesti. Nužni proceduralni procesi, u toku primarne perkutane koronarne intervencije (pPKI), kao i saznanja o distribuciji i vrstama lezija koronarnih arterija su od velikog značaja, te se preporučuje finalna evaluacija rizika neposredno nakon izvršene pPKI. Metode istraživanja podataka omogućavaju pronalaženje skrivenih obrazaca u podacima, otkrivanje njihovih uzročno-posledičnih veza I odnosa, te razvoj savremenih prediktivnih modela. Cilj: Kreiranje i testiranje jednostavnog, praktičnog i u svakodnevnoj praksi upotrebljivog prediktivnog modela za procenu intra-hospitalnog ishoda lečenja pacijenata obolelih od AIM sa ST-elevacijom (STEMI) lečenih pPKI. Metode: Istraživanje je unicentrična, retrospektivna, ali I prospektivna studija. U retrospektivnu studiju je uključeno 1495 pacijenta sa STEMI koji su lečeni na Klinici za kardiologiju Instituta za kardiovaskularne bolesti Vojvodine (IKVBV) kod kojih je u cilju rekanalizacije infarktne arterije izvršena pPKI, u periodu od decembra 2008. godine do decembra 2011. godine. Svaki pacijent je inicijalno predstavljen sa 629 obeležja sadržanih u postojećem IKVBV informacionom sistemu, koja čine demografske karakteristike, podaci iz anamneze i kliničkog nalaza, parametri biohemijskih analiza krvi priprijemu, parametri ehokardiografskog pregleda, angiografski i proceduralni detalji i šifre prijemnih dijagnoza. U svrhu istraživanja podataka korišćeno je programsko rešenje otvorenog koda Weka. Tokom evaluacije različitih algoritama izabran je algoritam koji daje najbolje rezultate po tačnosti predikcije i ROC parametru. U sklopu retrospektivnog dela izvršena je validacija prediktivnog modela desetostrukom unakrsnom validacijom na celom skupu podataka. Prospektivnom studijom je na uzorku od 400 pacijenata sa STEMI lečenih pPKI u toku 2015. godine izvršena dodatna validacija razvijenog prediktivnog modela. Za iste pacijente je izračunavat i GRACE skor rizika, te je upoređena njegova, i prediktivna moć razvijenog modela. Rezultati: Alternativno stablo odluke (ADTree) izdvojen je kao algoritam sa najboljim performansama u odnosu na ostale evaluirane algoritme. Cost sensitive klasifikacija je korišćena kao dodatna metodologija da bi se pojačala tačnost. ADTree stablo odluke izdvojilo je osam ključnih parametara koji najviše utiču na ishod intra-hospitalnog lečenja: sistolni krvni pritisak pri prijemu, ejekciona frakcija leve komore, udarni volumen leve komore, troponin, kreatinin fosfokinaza, ukupni bilirubin, T talas i<br />rezultat intervencije. Performanse razvijenog modela su: tačnost predikcije je 93.17%, ROC 0.94. Razvijeni model je na prospektivnoj validaciji zadržao performanse: tačnost predikcije 90.75%, ROC 0.93. Široko korišćeni GRACE skor je na prospektivnom skupu postigao ROC=0.86, što pokazuje da je razvijeni prediktivni model superiorniji u odnosu na njega. Zaključak: Razvijeni prediktivni model je jednostavan i pouzdan. Njegova implementacija u svakodnevnu kliničku praksu, omogućila bi kliničarima da izdvoje visokorizične pacijente, nakon reperfuzionog tretmana, a potom kod njih intenziviraju tretman i kliničko praćenje, a sa ciljem smanjenja incidence intra-hospitalnih komplikacija i povećanja njihovog preživljavanja.</p> / <p>Introduction: Risk stratification has become an integral component of modern treatment in clinical practice. Today, the diagnosis and treatment of acute myocardial infarction (AMI) use different risk scores as a prognostic instruments for short-term and long-term outcome of the disease. The necessary procedural processes during primary percutaneous coronary intervention (pPCI) as well as knowledge about the distribution and types of lesions in coronary arteries are of great importance, and a final risk evaluation is recommended directly after the pPCI. Methods of data mining allow finding hidden patterns in data, disclosure of their causal connections and relationships, and the development of modern predictive models. Aim: To create and test a simple, practical and usable predictive model in daily practice for the assessment of intrahospital treatment outcome of patients with AMI with STsegment elevation (STEMI) treated with pPCI. Methods: Presented research is unicentric, retrospective but also prospective study. Retrospective study included 1495 patients with STEMI who were admitted to the Clinics of cardiology of the Institute of Cardiovascular Diseases Vojvodina (IKVBV). For the purpose of recanalization of the infarct artery, pPCI has been performed to these patients during the period from December 2008 to December 2011. Each patient was initially described with 629 attributes from the existing information system of IKVBV. Those attributes consist of demographic characteristics, data from history and clinical findings, biochemical parameters of blood tests on admission, the echocardiographic parameters, angiographic and procedural details and admission diagnosis codes. For model development, an open source software solution Weka was used. During the evaluation of different algorithms, algorithm that gives the best results in terms of accuracy and ROC parameter was chosen. As part of the retrospective study, in order to assess the models performance, ten-fold cross-validation on the entire data set was used. A prospective study, on a sample of 400 patients with STEMI, treated with pPCI in 2015, performed additional validation of the developed predictive model. GRACE risk score was calculated for the prospective study patients and comparison with the developed model has been performed. Results: Alternative decision tree (ADTree) was isolated as an algorithm with the best performance in relation to other algorithms evaluated. Cost sensitive classification was used as an additional methodology to enhance accuracy. ADTree selected eight key parameters that most influence the outcome of intra-hospital treatment: systolic blood pressure on admission, left ventricular ejection fraction, stroke volume of the left ventricle, troponin, creatine phosphokinase, total bilirubin, T wave and the result of the intervention. The performance of the developed model are: the accuracy of the prediction is 93.17%, ROC 0.94. The developed model kept its performance in prospective validation: accuracy of prediction 90.75%, ROC 0.93. Widely used GRACE score achieved ROC = 0.86 in the prospective study patients, indicating that developed predictive model is superior to him. Conclusion: Developed predictive model is simple and reliable. Its implementation in everyday clinical practice, would allow clinicians to distinguish high-risk patients after reperfusion treatment, and then for them to intensify treatment and clinical follow-up, with an aim of reducing the incidence of intra-hospital complications and increase their survival.</p>
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Prognostički značaj gustine tumorskih pupoljaka i citoplazmatskih pseudofragmenata u tumorskom tkivu karcinoma kolona kod bolesnika u stadijumu II / Prognostic significance of density of tumor buds and cytoplasmic pseudofragments in stage II colonic carcinomaŠolajić Nenad 15 September 2016 (has links)
<p>UVOD: Karcinom kolona (KK) je velik javnozdravstveni problem usled visoke incidence i stope mortaliteta. Kod KK je stadijum bolesti najvažniji pojedinačni nezavisni faktor prognoze. U prisustvu nepovoljnih prognostičkih parametara, u koje spadaju visok histološki gradus, ileus, limfo-vaskularna i perineuralna invazija, nakon potencijalno kurativne operacije se kod pacijenata u stadijumu II indikuje primena adjuvantne hemioterapije koja ima pozitivan uticaj na ukupno preživljavanje i na produženje perioda bez bolesti. Međutim, relapsi bolesti nastaju kod nekih bolesnika bez negativnih prognostičkih faktora, što ukazuje na moguće postojanje drugih tkivnih faktora loše prognoze. U novije vreme se sve veća pažnja posvećuje fenomenu tumorskog pupljenja koje predstavlja pojavu tumorskih pupoljaka (TP), odnosno oligocelularnih grupa tumorskih ćelija koje se na invazivnom frontu tumora odvajaju od glavne tumorske mase. Ove tumorske ćelije poprimaju fenotip mezenhimnih ćelija i stiču sposobnost ameboidnog kretanja kroz ekstracelularni matriks, uz pomoć citoplazmatskih podija koje se na dvodimenzionalnim histološkim rezovima vizualizuju kao citoplazmatski pseudofragmenti (CPF). Značaj gustine TP i CPF je još uvek nedovoljno ispitan, ali postoje indicije da se radi o moćnom prediktoru biološkog ponašanja tumora. CILJ: Cilj je bio da se ispita zavisnost dužine perioda bez relapsa, veličine primarnog tumora, gustine peritumorske limfocitne infiltracije i konfiguracije tumorske margine od gustine TP i CPF kod bolesnika sa KK u stadijumu II. METODOLOGIJA: Istraživanjem je obuhvaćeno 114 bolesnika operisanih od KK u stadijumu II na Institutu za onkologiju Vojvodine, bez nepovoljnih prognostičkih faktora i bez indikacija za primenu adjuvantne hemioterapije. Mikroskopskom analizom rutinskih histoloških i imunohistohemijskih preparata utvrđivana je gustina TP i CPF, koja je zatim korelirana sa vremenom pojave relapsa, veličinom primarnog tumora, gustinom peritumorske limfocitne infiltracije i konfiguracijom tumorske margine. REZULTATI: Velika gustina TP i/ili CPF nađena je kod 45 tumora (39,5%). U ovoj grupi se relaps dogodio kod 26 bolesnika (57,8%). U grupi bolesnika sa malom gustinom TP/CPF relaps je registrovan u 4 slučaja (5,8%). Poređenje krivih preživljavanja pokazalo je da je verovatnoća relapsa značajno veća ako se u tumoru nalazi velika gustina TP/CPF (p<0,0001). Tumori sa velikom gustinom TP/CPF su imali najveći prečnik koji je varirao u rasponu od 25 do 100 mm, dok su tumori sa malom gustinom TP/CPF bili najvećeg prečnika od 20 do 110 mm (p=0,6744). Intenzitet peritumorskog limfoidnog odgovora je bio velik kod 13 tumora sa velikom gustinom TP/CPF (28,9%) i kod 17 tumora sa malom gustinom TP/CPF (24,6%), p=0,7747. Konfiguracija tumorske margine je bila infiltrativna u svim tumorima sa velikom gustinom TP/CPF, kao i kod 42 tumora sa malom gustinom TP/CPF (60,9%). ZAKLJUČAK: Velika gustina TP/CPF je nezavisan tkivni indikator loše prognoze kod bolesnika sa KK u stadijumu II, koji je ne korelira ni sa veličinom primarnog tumora ni sa intenzitetom peritumorskog limfoidnog odgovora. Velika gustina TP/CPF nije kompatibilna sa ekspanzivnom konfiguracijom tumorske margine, ali infiltrativna konfiguracija tumorske margine nije prediktor velike gustine TP/CPF.</p> / <p>INTRODUCTION: Colonic carcinoma (CC) is a serious public health problem due to its high incidence and mortality rate. Stage is the single most important independent prognosticator in patients with CC. In the presence of indicators of poor prognosis, including high histologic grade, ileus, lympho-vascular invasion and perineural invasion, there is a need for adjuvant chemotherapy after a potentially curative operation in patients with stage II CC, because the therapy improves both overall survival and disease-free survival. However, some patients with no documented poor prognostic factors suffer recurrences, which indicates that there may be some other tissue features that confer poor prognosis. In the recent publications there is an increasing interest in the phenomenon of tumor budding, a term assigned to the presence of small groups of discohesive tumor cells at the invasive front of the tumor – tumor buds (TB's). These cells acquire mesenchymal phenotype and gain the ability to migrate through the extracellular matrix by means of cytoplasmic extrusions which are visible on the two-dimensional immunohistologic sections and are called cytoplasmic pseudofragments (CPF's). Significance of density of TB's and CPF's is still to be evaluated, but the pool of evidence suggests that this is a powerful predictor of biologic behaviour of CC. AIM: The aim of this study was to determine the influence of density of TB's and CPF's on the risk of recurrence in patients with stage II CC. This research also attempted to establish whether there is a correlation between the density of TB's and CPF's and several other morphologic features such as tumor diameter, peritumoral lymphocytic response and the configuration of the tumor margin. METHODS: 114 patients with stage II CC were enrolled in the study. All the patients received surgery at the Institute of Oncology in Sremska Kamenica and no patient had indication for adjuvant chemotherapy. Microscopic analysis of routine histologic and immunohistochemical slides was performed to establish the density of TB's and CPF's, to estimate the intensity of the peritumoral lymphocytic response and to determine the configuration of the tumor margin. RESULTS: High density of TB's and/or CPF's was found in 45 tumors (39.5%). In this group recurrence occured in 26 patients (57.8%). In the group of patients with low density of TB/CPF in the tumor tissue 4 patients relapsed (5.8%). Comparison of survival curves showed that the probability of recurrence was significantly greater if the density of TB/CPF's was high (p<0.0001). Tumors with high density of TB/CPF's ranged from 25 to 100 mm in greatest diameter, while those with low density measured from 20 to 110 mm (p=0.6744). Intensity of peritumoral lymphocytic response was high in 13 tumors with high density of TB/CPF's (28.9%) and in 17 tumors with low density of TB/CPF's (24.6%), p=0.7747. All tumors with high density of TB/CPF's and 42 tumors with low density of TB/CPF's (60.9%) had infiltrative configuration of tumor margin. CONCLUSION: High density of TB/CPF's is an independent indicator of poor prognosis in patients with stage II CC and it correlates neither with tumor diameter nor with intensity of peritumoral lymphocytic response. High density of TB/CPF's is not compatible with the expansive configuration of tumor margin, but the infiltrative configuration of tumor margin is not a predictor of high density of TB/CPF's.</p>
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Avaliação do acurácia de Test of Infant Motor Performance e da ultrassonografia de crânio no prognóstico neurológico de recém-nascido pré-termo de risco / Accuracy of the Test of Infant Motor Performance and cranial ultrasonography in the neurological prognosis of very low birthweight preterm newborn infantsGonçalves, Helena 31 May 2011 (has links)
Objetivo: Verificar a acurácia do Test of Infant Motor Performance (TIMP) e da ultrassonografia de crânio (USC) no diagnóstico neurológico precoce após os 10 meses de idade corrigida em recém-nascidos pré-termo (RNPT) Metodologia: Amostra não aleatória constituída por 59 RNPT (idade gestacional ao nascimento 32 semanas ou peso ao nascimento 1500 gramas) seguidos em média até os 12 meses de idade corrigida. Os resultados da USC foram agrupados em 3 intervalos: 1) de 0 a 15 dias, 2) de 16 a 30 dias e 3) de 31 a 45 dias. Os achados da USC foram classificados em normal e anormal (anormalidades moderada e grave). O TIMP foi aplicado mensalmente, do primeiro retorno após a alta hospitalar até o 4° mês de idade corrigida. As avaliações foram agrupadas em 5 intervalos, correspondentes às avaliações antes do termo, 1°, 2°, 3° e 4° meses de idade corrigida. Os resultados do TIMP foram classificados em normal (média e média baixa) ou anormal (abaixo da média e muito abaixo da média). A avaliação neurológica foi realizada em média aos 12 meses de idade corrigida, e usada como padrão-ouro. Foram calculados os valores de sensibilidade, especificidade e valores preditivos positivos (VPP) e negativos (VPN) para o TIMP e para a USC neonatal. Resultados: A paralisia cerebral foi diagnosticada em 6 crianças. Observamos que a USC apresentou alta sensibilidade (> 70%) assim como altos VPN (>88%) em todos os intervalos. Para a USC, especificidade e VPP foram baixos em todos os intervalos. A sensibilidade do TIMP foi baixa, exceto para o intervalo 0, e os VPP foram baixos em todas as idades. A escala TIMP apresentou alta especificidade (75%, 85%) no 3° e 4° meses e altos VPN (> 77%) em todos os intervalos. Conclusão: Concluímos que os RNPT com pontuação normal no 3° e 4° meses do TIMP tem grandes chances de não desenvolver PC enquanto que RNPT com anormalidades graves e persistentes à USC tem maiores chances de um prognóstico neurológico anormal / Objective: Calculate the accuracy of the Test of Infant Motor Performance (TIMP) and the cranial ultrasonography (CUS) in the neurological outcome after 10 months of corrected age of preterm infants. Methods: Non-random sample of 59 preterm newborn infants (gestational age 32weeks or birth weight1500g) were followed up to a mean of 12 months corrected age. CUS results were grouped into 3 periods: 1) from 0 to 15 days; 2) from 16 to 30 days, and 3) from 31 to 45 days of life. CUS findings were rated into two groups: normal and abnormal (moderate and severe abnormalities). TIMP was applied monthly, from the first outpatient visit after hospital discharge until four months corrected age. The evaluations were grouped into five intervals, corresponding to the assessments performed before term age, 1st, 2nd, 3rd and 4th month of corrected age. TIMP results were ranked as normal (average, low average) or abnormal (below average and far below average). A full neurological examination was performed at a mean of 12 months of corrected age, and used as gold standard. The sensitivity, specificity, positive predictive (PPV) and negative predictive (NPV) values for TIMP and CUS were calculated. Results: Cerebral palsy was diagnosed in six infants. We observed that CUS had a high sensitivity (> 70%) in all intervals as well as high NPV (>88%). For CUS, specificity and PPV were low in all intervals. TIMP sensitivity was low, except for interval 0, and PPV were low at all ages. TIMP scale showed high specificity in the 3rd and 4th month (75%, 85%) and high NPV (> 77%) at all ages. Conclusions: We conclude that preterm infants with normal score at the 3rd and 4th months of TIMP are likely to develop normally while infants with severe and persistent abnormalities in the CUS examinations are more likely to have an abnormal neurological outcome
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Reavaliação do papel da determinação das concentrações séricas do IGF-1 e IGFBP-3 na investigação de crianças com baixa estatura / Re-evaluation of the role of IGF-1 and IGFBP-3 serum concentrations in the assessment of children with short statureLima, Thaís Hissami Inoue 18 April 2019 (has links)
IGF-1 e IGFBP-3 são medidas indiretas da secreção de GH e ferramentas úteis na avaliação do eixo GH/IGF-1. No diagnóstico de deficiência de GH (DGH) estes peptídeos são avaliados pela idade cronológica. Nosso estudo avaliou a capacidade discriminativa desses peptídeos na identificação de pacientes com DGH e comparou a performance dos escores de desvio padrão do IGF-1 e do IGFBP-3 avaliados para idade cronológica (escore-ZIC), idade óssea (escore-ZIO) e estadio puberal (escore-ZIP) no diagnóstico de DGH. Trata-se de um estudo retrospectivo, transversal, com levantamento de dados de prontuário de pacientes pediátricos com distúrbios de crescimento acompanhados em nosso serviço. Os pacientes foram classificados como DGH ou suficientes de GH (não-DGH). O IGF-1 e o IGFBP-3 foram dosados pelo ensaio quimioluminescência - IMMULITE® e foram calculados o escore-ZIC, escore-ZIO e escore-ZIP. Foram avaliados 50 pacientes classificados como DGH e 187 como não-DGH. Os escores-ZIC, escores-ZIO e escores-ZIP do IGF-1 e do IGFBP-3 foram significativamente menores no grupo DGH em comparação com o grupo não-DGH (p < 0,001). O escore-ZIC do IGF-1 apresentou desempenho discriminativo superior ao escore-ZIC do IGFBP-3 na identificação de pacientes com DGH [área sob a curva ROC (AUC) 0,877 e 0,766, respectivamente, p = 0,001], em que o IGF-1 apresentou melhor sensibilidade (92% vs 45,2%) e o IGFBP-3 melhor especificidade (93,8% vs 69%). Entretanto, o valor preditivo positivo, considerando uma prevalência estimada de DGH de 2% entre crianças com baixa estatura, foi de 5,7% para o escore-ZIC do IGF-1 e de 13,1% para o do IGFBP-3, com valores preditivos negativos semelhantes. O escore-ZIO do IGF-1 demonstrou melhor desempenho discriminativo que o escore-ZIC sem atingir significância estatística (AUCs de 0,902 e 0,877, respectivamente, p=0,29). Mas essa superioridade não foi observada com o escore-ZIO do IGFBP-3. Nos pacientes em idade pré-púbere, não houve diferença estatisticamente significante entre o desempenho do escore-ZIC e escore-ZIO das concentrações séricas do IGF-1 e do IGFBP-3. Já nos pacientes em idade puberal houve uma melhora significativa da especificidade dos escore-ZIO e escore-ZIP do IGF-1 em relação ao escore-ZIC (de 65,6% para 92,7% e 98,4%), apesar da redução da sensibilidade (de 91,3% para 72,2% e 63,6%, respectivamente). Além disso, os valores preditivos positivos (VPP) do escore-ZIO e do escore-ZIP apresentaram uma melhora significativa em relação ao escore-ZIC do IGF-1 (16,8%, 44,8% e 5,1%, respectivamente), sem prejuízo nos valores preditivos negativos. A avaliação combinada de IGF-1 e IGFBP-3 em comparação com o escore-Z do IGF-1 isolado apresentou melhor sensibilidade (de 92% para 94,4%) quando somente um escore-Z desses peptídeos está baixo e melhor especificidade (de 69% para 95,7%) quando os escores-Z de ambos os peptídeos estão baixos / IGF-1 and IGFBP-3 are an indirect measure of the GH secretion and are a useful tool in the evaluation of the GH/IGF-1 axis. These peptides are usually evaluated according to the chronological age in the diagnosis of GH deficiency (GHD). Our study evaluated the diagnostic value of IGF-1 and IGFBP-3 in the diagnosis of GHD and compared their performance assessed by chronological age, bone age and pubertal status. This is a retrospective, cross-sectional study; data of pediatric patients with growth disorders evaluated in our tertiary outpatient clinic were retrieved from medical records. The patients were classified as GHD or GH sufficient (non-GHD). The IGF-1 and IGFBP-3 were measured by a chemiluminescent immunometric assay (IMMULITE®) and these values were transformed into standard deviation scores according to chronological age (SDSCA), bone age (SDS-BA) and pubertal status (SDS-PS). 50 patients were classified as GHD and 187 patients as non-GHD. The IGF-1 and IGFBP-3 SDSCA, SDS-BA and SDS-PS were significantly lower in the GHD group in comparison to the non-GHD group (p < 0.001). The IGF-1 SDS-CA had a superior discriminatory performance than the IGFBP-3 SDS-CA in the diagnosis of GHD [area under the ROC curve (AUC) 0.877 and 0.766, respectively, p = 0.001]. The IGF-1 SDS-CA had a higher sensitivity (92% vs 45.2%) and the IGFBP-3 SDSCA had a higher specificity (93.8% vs 69%). However, the predictive value of a positive result, considering an estimated GHD prevalence of 2% among children with short stature was 5.7% for the IGF-1 SDS-CA and 13.1% for the IGFBP-3 SDS-CA, with similar predictive values of a negative result. The IGF-1 SDS-BA had a better discriminatory performance than the IGF-1 SDS-CA, though not statistically significant (AUCs 0.902 and 0.877, respectively, p=0.29). There was no difference in the performance of the IGFBP-3 SDS-CA and SDS-BA. The diagnostic value of the IGF-1 and IGFBP-3 SDS-CA and SDS-BA of patients of pre-pubertal age was similar. On the other hand, in patients of pubertal age, there was a significant improvement of the specificity of the IGF-1 SDS-BA and SDSPS in comparison to the IGF-1 SDS-CA (from 65.5% to 92.7% and 98,4%), albeit the decay on the sensitivity (from 91.3% to 72.2% and 63.6%, respectively). Furthermore, the positive predictive values of the IGF-1 SDS-BA and SDS-PS were higher than the IGF-1 SDS-CA (16.8%, 44.8% and 5.1%, respectively), with similar negative predictive values. The evaluation of IGF-1 and IGFBP-3 assessed simultaneously in comparison to IGF-1 had a better sensitivity (from 92% to 94.4%) when either one of these peptides is low, and a better specificity (from 69 to 95.7%) when both the peptides are low
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