Introdução: O aumento alarmante da obesidade em todo mundo é um fator independente para o aumento da prevalência de doenças crônicas, como diabetes, hipertensão arterial e doença hepática gordurosa não alcoólica (DHGNA). A DHGNA engloba um amplo espectro de doença desde esteatose simples sem sinais inflamatórios, evoluindo para esteatohepatite (ENA) e até cirrose. Por ser uma patologia multifatorial sua patogênese e terapêutica ainda apresentam pontos obscuros. A resistência à insulina é um dos fatores que já foram determinados como importantes na fisiopatogênese da DHGNA e, está diretamente relacionado ao estilo de vida e hábitos alimentares. Objetivo: Avaliar a correlação entre a presença da gordura visceral e subcutânea à resistência insulínica, síndrome metabólica, medidas antropométricas e hábitos alimentares em pacientes portadores DHGNA. Resultados: Sessenta por cento dos pacientes com DHGNA apresentavam Síndrome Plurimetabólica de acordo com os critérios do ATP III. Dentre os critérios mais prevalentes da síndrome metabólica, níveis baixos HDL e circunferência de cintura (CC) aumentada ocorreram em 56%. Ao dividirmos os pacientes em grupos, os critérios se modificaram. Nos pacientes portadores de esteatose simples, o critério mais prevalente foi CC 77%. Já naqueles com ENA o aumento do nível de triglicérides ocorreu em 68% dos pacientes, sendo o de maior prevalência. As correlações entre CT e IMC (p=0,001), CC (p=0,003) e percentual de massa gorda (p=0,031), apresentam significância estatística negativa entre os pacientes com DHGNA. Não houve significância estatística entre CT e HOMA, ingestão total de energia, proteínas, carboidratos e lipídios nestes pacientes mesmo quando foram divididos de acordo com o grau de inflamação, esteatose e ENA. Por outro lado, a CC ao ser correlacionada com IMC (p=0,000), HOMA (p=0,049), ingestão total de energia (p=0,043), lipídios e dos ácidos graxos mono (p=0,020) e poliinsaturados (0,045) apresentaram significância estatística nos pacientes com DHGNA. Quando divididos segundo o grau de esteatose houve correlação positiva entre CC e HOMA (p=0,045) nos pacientes com esteatose simples. Já nos pacientes portadores de ENA houve correlação positiva entre CC e ingestão total de calorias (p=0,031). Houve diferença estatística positiva quanto ao consumo de lipídios totais (p=0,005) entre o grupo de esteatose e ENA, onde os pacientes com ENA, tinham um maior consumo de lipídios. Conclusões: A circunferência de cintura se mostrou melhor parâmetro de diagnóstico complementar ao ser comparado com a tomografia computadorizada em pacientes com DHGNA. Ao associarmos o IMC com a CC conseguimos obter uma avaliação nutricional mais fidedigna dos riscos de doenças decorrentes da síndrome metabólica. O alto consumo de lipídios apresentou correlação positiva com maior grau de inflamação em pacientes com DHGNA. / Introduction: The dramatic increasing of obesity in the world is a predictive factor to increase the prevalence of chronic diseases, as type II diabetes, hypertension and Nonalcoholic fatty liver disease (NAFLD). It is part of large spectrum of liver damage ranging from simple steatosis and cirrhosis. The pathogenesis of NAFLD is multifactorial and some points in the mechanisms and therapeutic still unknown. The insulin resistance is the major risk factors, recognized in the pathophysiology of NAFLD and it is strongly related with life style and diet. Objective: Evaluate the correlation between visceral and subcutaneous fat with insulin resistance, presence of metabolic syndrome, anthropometric measurements and dietary intake in patients with NAFLD. Results: Sixty percent of patients with NAFLD, classified by ATPIII criteria, had the metabolic syndrome. Waist circumference and low HDL -C were the most positive criteria, observed in 56% of total cases. However the criteria modifies when the group were divided. In patients with simple steatosis WC was the most prevalent criteria 77%, where as in NASH patients the high level of TGL 68%, was the most prevalent. Correlations between CT and BMI (p=0,001), WC (p=0,033) and fat mass (p =0,031) had a negative statistic significant correlation in all cases of NAFLD. No significant associations were found between CT (umbilical circumference) and fat mass, WC, HOMA, Intake of calories, carbohydrates, proteins, lipids and fat acids in patients divided in steatosis and NASH patients. The correlation between Waist circumference (WC) with BMI (p=0,000), HOMA (p:0,049), total of energy intake (p=0,043) , monounsaturated (p:0,020) and polyunsaturated (p:0,045) fat acids intake showed a statistic significance in all cases of NAFLD. Significant different correlations were found as the group were divided in steatosis and NASH cases. The values of fat mass correlated with WC was (p: 0,045) in the steatosis group where as in NASH patients the only correlation found was WC and total consumption of daily energy (p=0,031). NASH patients showed a statistic higher intake of lipids (p=0,005), compared with steatosis patients. Conclusions: CT measurement of visceral fat did not contribute to differential diagnosis as much as WC in patients with NAFLD. The use of both measurements BMI and WC showed to be a better predictor of the risks of Metabolic Syndromes. NASH subjects had a higher intake o total fat as well as of lipid fractions.

Introdução: O presente estudo visa elucidar a apresentação anatômica da vasculatura medular em exame angiotomográfico e suas diferenças entre pacientes aortopatas e não aortopatas na população brasileira. Objetivos: Determinar as características da artéria de Adamkiewicz (AKA) e artéria espinhal anterior (ASA) por método não invasivo. Secundariamente, determinaremos a distribuição anatômica da AKA na população brasileira e a influência de determinadas aortopatias e comorbidades na identificação da AKA. Casuística: Cento e quinze angiotomografias elegíveis realizadas no Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo foram avaliadas e separadas entre pacientes aortopatas e não aortopatas. Trinta e dois (52,5%) homens e 29 mulheres constituíram o grupo não aortopata e 30 (56,6%) homens e 23 mulheres constituíram o grupo de aortopatas. Método: Análise prospectiva de angiotomografias realizadas em aparelho de 320 detectores através de software open-source OsiriX e identificação da AKA e ASA por reconstrução multiplanar tridimensional. Dados clínicos e sociodemográficos foram estratificados. Resultados: A AKA foi identificada em 78,7% dos integrantes do grupo não aortopata e em 40,7% dos pacientes aortopatas (p =< 0,0001). A ASA foi identificada em 80,3% dos integrantes do grupo não aortopata e em 46,3% dos pacientes aortopatas (p=0,0001). Em 53 (73,6%) casos a AKA originou-se do lado esquerdo. Discussão: A angiotomografia é exame de rotina no pré-operatório de doenças aórticas. O presente trabalho apresentou detecção da AKA em grupo não aortopata equiparável com a literatura, apesar do aumento de detectores no aparelho de tomografia e a identificação da AKA em grupo aortopata pouco abaixo da literatura, mas significativamente diferente do grupo não aortopata: maior proporção de identificação da AKA e ASA em pacientes não aortopatas. Houve diferença na distribuição da AKA em comparação com a literatura. Conclusão: A detecção da AKA e ASA pelo método proposto é factível, porém não ocorre na totalidade dos pacientes. A AKA e ASA são mais identificáveis em pacientes não aortopatas e sua distribuição na população estudada não se assemelha à literatura. A origem da AKA é mais frequente entre T10 e T12 à esquerda / Introduction: This study investigated differences in spinal vasculature between healthy and diseased aortas among Brazilian population. Objective: The study aimed to identify and describe the spinal vascular anatomy, evaluate Anterior Spinal Artery (ASA) and Adamkiewicz artery (AKA) characteristics using non-invasive multidetector computed tomography (CT), as well as examine differences between groups with and without aortic disease. The secondary aim was to evaluate anatomic distribution of AKA level and side and the influence of clinical factors in its detection. Methods: CT scans of 115 patients from Instituto do Coração do Hospital das Clínicas da Faculdade de Medicina da Universidade de São Paulo were evaluated in terms of detection rate and AKA level and side. The results were also compared with data compiled from a review of the English language literature on this topic. We analysed 320-detector CT scans using OsiriX open source software. Furthermore, we identified the AKA and ASA using tridimensional multiplannar reconstruction. Clinical and demographics data were retrieved. Results: AKA identification showed higher detection rate in patients with healthy aortas (78.7%) compared to diseased aortas (40.7%) p < 0.0001. ASA was identified in 80.3% of the healthy aortas patients and 46.3% of the diseased aortas patients (p=0.0001). In 53 (76.6%) cases, the AKA originated from a left intercostal artery. Discussion: CT scan is a routine preoperative exam for aorta diseases. We observed a detection rate similar to that reported in previous literature on healthy aortas, in spite of the CT having more detectors. Furthermore, AKA identification in aorta diseased group was below literature, but statistically different from the healthy aorta group, higher AKA and ASA identification was found in healthy aorta group. The results indicated significant difference between previous literatures and our study in AKA detection. Conclusions: AKA detection using proposed method is feasible but is not detected in all patients. AKA and ASA have a higher detection rate in patients with a healthy aorta. The proposed method and data compiled from the literature did not show similar AKA level distribution. AKA originated more frequently from the left side between T10 and T12

Application of smart curing concept called internal curing (IC) is the most promising strategy for mitigating autogenous shrinkage and related early-age cracking in cement-based materials with low water-to-cement ratio. There are still many theoretical and practical questions that need to be answered before IC could become a standard method. Many of these questions concern the most appealing of water-regulating additives for IC called Superabsorbent Polymers (SAP). The clear linkage between SAP material properties, the moment of water release and the effect on autogenous shrinkage is still missing, which blocks formulating recommendations for use of particular potential IC agents in concrete construction. In this treatise various aspects that are decisive for effectiveness of IC in mitigating autogenous shrinkage were examined. The choice of materials was purposefully limited to two compositions of Ultra-High Performance Concrete (UHPC), one fine-grained and one coarse-grained mixture, and one particular, in-depth characterized SAP. The objectives of examination which shaped the final experimental programme were: assessment of IC agent absorption capacity, specification of periods of water migration from fresh concrete mixture into SAP and from SAP back into hardening concrete, determination of effect of SAP addition on cement hydration, evaluation of IC influence on and determination of start of effective autogenous shrinkage and, finally, assessment of autogenous shrinkage with selfsame IC agent but for different matrices. Ideally, description of the mechanisms behind the action of IC at different stages of concrete life and reasoning of differences observed for the UHPCs under investigation had to be provided. First, the main components of the system – UHPC and SAP material – were characterized as to their suitability for IC application. Special attention was paid to the material properties which affect water transport. Usage of different testing methods was necessary here and included: testing with ESEM, FT-IR, tea-bag test, sol fraction content examination and X-ray computed tomography (for SAP) as well as air content measurement and various methods for characterization of the porosity and other features of the microstructure. The observed delay in the start of pozzolanic reactions in case of fine-grained UHPC was rather surprising, but, under consideration of porosity, shed new light on permeability of young UHPC. The work at hand revealed numerous methods that can be used for studying the absorption capacity of polymers, but hardly representative for the behaviour of those polymers within concrete matrix. Because of its general availability and the relatively robust testing procedure, it was decided to focus on possibilities and limitations of using tea-bag test for evaluation of absorption capacity of SAP. New interpretation of tea-bag test results was deduced which enabled assessment of maximum absorption capacity of SAP from measurement of consistency of concrete before and after modification with IC. Influence of IC on hydration process was revealed by using two non-destructive methods, in particular ultrasonic measurement and concrete temperature record. It could be shown that the ionic polymer exhibits complex effects including retardation and acceleration of individual chemical processes. Additionally, X-ray computed tomography (CT) and instrumented ring tests were performed in order to understand scientific significance of the characteristic event appearing during shrinkage measurements, taken as time-zero (= starting point for evaluation of autogenous shrinkage data). Linkage of time-zero with certain phenomenon, e.g., changes of the SAP particles volume or specific value of yield stress, but not with final set, was suggested for the future investigations. By using two setups based on corrugated tube protocol it was possible to register and compare autogenous shrinkage of both UHPCs without and with modification by IC. The effectiveness of IC was shown to be dependent on the matrix in which IC was implemented. This was related to the observed changes in pore percolation that resulted from different absorption behaviour of SAP in the two UHPCs under investigation. Furthermore, the effect of fibres on effectiveness of IC was discussed. Description and discussion of mechanisms behind IC was supported by measurement of capillary pressure, total shrinkage tests with simultaneous mass loss measurement, free autogenous shrinkage tests and the CT measurement. Valuable source of information was furthermore the in-depth literature review. The most appealing finding of the work and the biggest paradox revealed was high efficiency of IC in mitigating autogenous shrinkage and simultaneously appearance of stage where very clear reverse in mode of polymer volume change was observed. This suggests partial reabsorption of water initially released. This puts interpretation of operative shrinkage mechanisms and ones standing behind IC effect in a new perspective. / Die innere Nachbehandlung (Internal Curing – IC) ist die derzeit aussichtsreichste Strategie, um das in zementgebundenen Baustoffen mit niedrigen Wasser/Zement-Werten ausgeprägt auftretende autogene Schwinden wirksam zu verringern und die damit einhergehende Rissbildung in jungem Beton zu vermeiden. Vor einer breiten baupraktischen Anwendung des IC sind noch viele offene Fragen zu beantworten. Die meisten dieser Fragen betreffen die derzeit interessanteste Klasse von wasserregulierenden Stoffen für das IC – die superabsorbierenden Polymere (SAP). Von entscheidender Bedeutung ist hier der noch weitgehend unerforschte Zusammenhang zwischen den Materialeigenschaften der SAP, dem Zeitpunkt der Wasserabgabe und der Auswirkung auf das autogene Schwinden. In der vorliegenden Arbeit werden verschiedene Einflussfaktoren auf die Wirksamkeit von SAP zur Verringerung des autogenen Schwindens untersucht. Für die Experimente wurde ein feinkörniger und ein grobkörniger ultra-hochfester Beton (UHPC) sowie ein schon detailliert charakterisiertes SAP genutzt. Das experimentelle Programm wurde auf folgende Untersuchungsziele ausgerichtet: Absorptionsvermögen der SAP, Zeitfenster der Wassermigration aus dem Frischbeton in das SAP sowie vom SAP in den erhärtenden Beton, autogenes Schwindmaß sowie effektiver Beginn des autogenen Schwindens. Ziel der Arbeiten ist die Beschreibung der Mechanismen, die IC zugrundliegen – und dies zu verschiedenen Betonaltern und unter Berücksichtigung der an den untersuchten UHPC beobachteten Unterschiede. Bei der Charakterisierung der Hauptkomponenten des betrachteten Systems – UHPC und SAP – wurde auf die Materialeigenschaften fokussiert, die den Wassertransport beeinflussen. Dazu wurden u. a. folgende Untersuchungsmethoden angewendet: ESEM, FT-IR, Teebeuteltest, Sol-Fraction Test, Röntgentomographie (für SAP) sowie verschiedene Verfahren zur Charakterisierung der Poren im Beton. Im feinkörnigen UHPC wurde überraschenderweise ein verzögerter Beginn der puzzolanischen Reaktion festgestellt, der bei Berücksichtigung der vorliegenden Porosität zu einer Neubewertung der Permeabilität von UHPC in jungem Alter führte. In der vorliegenden Arbeit werden verschiedene Methoden zur Beschreibung des Wasserabsorptionsvermögens von SAP benannt, deren Aussagekraft bei Anwendung dieser Polymere im Beton aber sehr eingeschränkt ist. Aufgrund seiner einfachen Verfügbarkeit und Robustheit wurde daher der Teebeutetest zur Bestimmung der Wasserabsorption des SAP genutzt. Die Wasserabsorption der SAP im Beton wurde durch Gegenüberstellung von Konsistenzmessungen am Beton vor und nach Zugabe von SAP und Ergebnissen der Teebeuteltest abgeschätzt. Der Einfluss des IC auf die Hydratation wurde zerstörungsfrei mit Ultraschall- und Betontemperaturmessungen erfasst. Auf dieser Grundlage konnten Hypothesen zu den komplexen Wechselwirkungen zwischen ionischem Polymer und der Beschleunigung oder Verzögerung einzelner chemischer Prozesse formuliert werden. Mit Hilfe von instrumentierten Ringversuchen und X-ray Computertomographie wurden die Auswirkungen des IC mit SAP auf das autogene Schwinden, den Aufbau von Zwangsspannungen bei behindertem Schwinden und Time-Zero diskutiert. Dabei konnte ein Zusammenhang zwischen Time-Zero und verschiedenen Phänomenen, wie z. B. Volumenänderung des SAP oder der Fließgrenze des erhärtenden Betons, nicht aber zum Ende des Erstarrens aufgezeigt werden. Das autogene Schwinden beider untersuchter UHPC (jeweils mit und ohne IC) wurde mit Hilfe von Corrugated Tube-Versuchen gemessen. Es konnte gezeigt werden, dass wie Wirksamkeit des IC von der Betonzusammensetzung sowie der in den UHPC infolge Wechselwirkungen mit den SAP verschieden ausgebildeten Porenstruktur der Matrix abhängt. Weiterhin konnte ein Einfluss von Faserzugaben auf die Wirksamkeit des IC gezeigt werden. Die Beschreibung und Diskussion der Mechanismen des IC wurde durch Messungen des Kapillardrucks, des Gesamtschwindens, des freien autogenen Schwindens, des Masseverlustes und Computertomographie unterstützt. Eine wichtige Erkenntnisquelle war zudem die umfangreich gesichtete und diskutierte Literatur. Das interessanteste und zugleich paradoxe Ergebnis der Untersuchungen ist die Tatsache, dass die bei Einsatz von SAP beobachtete Verringerung des autogenen Schwindens eindeutig mit einer zeitgleichen Umkehr der Volumenänderung der SAP einhergeht: die bis dahin dominierende Wasserabgabe geht in eine erneute Wasseraufnahme über. Dies stellt die Interpretation der Triebkräfte des Schwindens und die dem IC zugrundliegenden Mechanismen in einen neuen Zusammenhang.

<p>Oralni karcinom je po učestalosti &scaron;esta najče&scaron;ća maligna bolest u svetu čija incidenca varira u različitim geografskim područjima. Predstavlja 5% svih novootkrivenih malignih tumora godi&scaron;nje i čini 14% svih malignih tumora glave i vrata. Pod oralnim karcinom podrazumevamo planocelularni karcinom obzirom na činjenicu da on čini preko 90% malignih tumora oralne lokalizacije, dok se u manjem procentu javljaju drugi tumori (maligni tumori malih pljuvačnih žlezda, limfomi, mezenhimni tumori). Oralni karcinom podrazumeva karcinome koji se javljaju u sledećim anatomskim regijama: sluznici prednje 2/3 jezika, poda usta, obraza, gingivi gornje i donje vilice, retromolarnom trouglu, kao i sluznici mekog i tvrdog nepca. Najče&scaron;ća lokalizacija oralnog planocelularnog karcinoma je sluznica pokretnog dela jezika i poda usta. Oralni karcinom se če&scaron;će javlja kod mu&scaron;karaca (odnos mu&scaron;karci:žene je 3:1) verovatno zbog većeg procenta rizičnog pona&scaron;anja kod mu&scaron;karaca. Najče&scaron;će se javlja u &scaron;estoj i sedmoj deceniji života (medijana je 62 godine) iako se poslednjih godina sve če&scaron;će javlja kod mlađih od 45 godina. Faktori rizika za oboljevanje su dobro poznati. Na prvom mestu se izdvaja pu&scaron;enje duvana (značajna je dužina pu&scaron;enja, da li pacijent pu&scaron;i lulu ili cigaretu, da li žvaće duvan, kao i dužina trajanja apstinencije). Smatra se da je smrtnost kod oralnog karcinoma direktno povezana sa brojem popu&scaron;enih cigareta na dan. Preko 75% pacijenata sa oralnim karcinomom anamnestički daje podatak o prekomernoj upotrebi alkohola. Postoji sinergističko dejstvo alkohola i cigareta, dugotrajna ekspozicija ovim faktorima rizika dovodi do pojave &ldquo;polja kancerizacije&ldquo;, pojave genetske nestabilnosti i razvoja tumora. Kod oralnog planocelulranog karcinoma primećene su hromozomske abnormalnosti koje su rezultat o&scaron;tećenja DNK i uključuju promene genetskog materijala na hromozomima.Jedna od najče&scaron;ćih genetskih abnormalnosti kod oralnog planocelularnog karcinoma je mutacija r53 gena koji se nalazi na kratkom kraku hromozoma 17 i predstavlja tumor supresor gen. Planocelularni karcinom nije te&scaron;ko dijagnostikovati kada postane simptomatski. Pacijent se žali na bol, krvavljenje, otalgiju, otežano gutanje, smanjenje pokretljivosti jezika. Neretko je prvi simptom metastatski uvećan limfni čvor na vratu jer bolesnici ne primećuju ili ignori&scaron;u oralnu patologiju. Dijagnoza oralnog karcinoma se postavlja na osnovu detaljno uzete anamneze, kliničkog pregleda i patohistolo&scaron;ke verifikacije. Oralni planocelularni karcinom se javlja u tri klinike forme: egzofitična, endofitična i infiltrativna. Zlatni standard za dijagnozu oralnog karcinoma je biopsija i patohistolo&scaron;ka verifikacija, pri čemu se može primeniti &bdquo;punch&ldquo; biopsija, inciziona biopsija ili eksciziona biopsija kod manjih promena. TNM &bdquo;staging&ldquo; sistem AJCC (American Joint Committee on Cancer) se danas standardno koristi za klinički &bdquo;staging&ldquo; oralnog karcinoma i bazira se na podacima dobijenim kliničkim pregledom i &bdquo;imaging&ldquo; metodama. Sam &bdquo;staging&ldquo; je bitan kako zbog komunikacije među lekarima koji učestvuju u lečenju bolesnika tako i zbog standardizacije prognoze. T stadijum označava veličinu primarnog tumora, N stadijum označava regionalnu nodalnu zahvaćenost dok M stadijum prikazuje prisustvo udaljenih metastaza. Terapija patohistolo&scaron;ki dokazanog oralnog karcinoma zahteva multidisciplinarni pristup. Osnova terapije oralnog planocelularnog karcinoma je hirur&scaron;ko lečenje koje podrazumeva ablativno i rekonstruktivno hirur&scaron;ko lečenje. Osnovni princip ablativne hirurgije kod oralnog karcinoma je resekcija primarnog tumora sa najmanje 1cm negativnim hirur&scaron;kim marginama. Pored ablacije tumora hirur&scaron;ko lečenje podrazumeva i uklanjanje regionalnih limfnih čvorova vrata. Cilj disekcije vrata je da se kod klinički evidentnih metastaza iste uklone (terapijska disekcija) ili da se uklone okultne metastaze koje su klinički neevidentne (elektivna disekcija). Oralni planocelularni karcinom spada u tumore sa visokom stopom smrtnosti, većom nego &scaron;to je kod limfoma, laringealnog karcinoma, karcinoma testisa i endokrinih karcinoma. Stopa petogodi&scaron;njeg preživljavanja je direktno povezana sa veličinom tumora, prisustvom metastaza u regionalnim limfnim čvorovima i prisutvom udaljenih metastaza. Prosečno trogodi&scaron;nje preživljavanje bolesnika sa oralnim karcinomom je 52% dok je prosečno petogodi&scaron;nje preživljavanje oko 39% i ove stope se nisu mnogo menjale tokom godina bez obzira na nova saznanja i nove pristupe lečenju oralnog planocelulanog karcinoma. Ciljevi istraživanja su da se utvrdi da li postoji korelacija debljine OPK izmerene kompjuterizovanom tomografijom i svetlosnim mikroskopom, da li dubina invazije OPK i volume tumora mogu biti prediktivni faktor za razvoj regionalnih cervikalnih metastaza kod oralnog planocelularnog karcinoma. Istraživanje je uključilo 65 konsekutivnih bolesnika oba pola lečenih od oralnog karcinoma na Klinici za maksilofacijalnu hirurgiju Kliničkog centra Vojvodine. Dijagnoza oralnog karcinoma je postavljena na osnovu anamneze, kliničkog pregleda i biopsije. U sklopu TNM &bdquo;staging&ldquo;-a bolesnika načinjen je pregled glave i vrata i grudnog ko&scaron;a kompjuterizovanom tomografijom (CT) na osnovu kog smo dobili podatak o dimenzijama tumora. Na osnovu kliničkog nalaza i analize CT nalaza planiralo se operativno lečenje u skladu sa bolesnikovim TNM statusom. Postoperatativni patohisto&scaron;ki preparati je pregledan od strane istog patologa. Parametri koji će su određivani su sledeći: 1. Veličina tumora (2 dimenzije) izmerene na osnovu CT pregleda izražene u cm 2. Debljina tumora izmerena na osnovu CT pregleda izražena u cm 3. Veličina tumora (2 dijametra) na makroskopskom preparatu izražena u cm 4. Debljina tumora na mikroskopskom preparatu izmerena svetlosnim mikroskopom izražena u cm 5. Dubina invazije tumora na mikroskopskom preparatu izmerena svetlosnim mikroskopom izražena u mm 6. Volumen tumora koji se izračunavao prema formuli: VT=&pi;/6 x maksimalni dijametar tumora A x minimalni dijametar tumora B x dubina invazije tumora i izražava se u cm&sup3; 7. Broj metastatski izmenjenih limfnih čvorova u disekatu vrata 8. Ukupan broj patohistolo&scaron;ki ispitanih limfnih čvorova u disekatu vrata Nakon prikupljanja planiranog materijala urađena je statistička obrada podataka. Statistička analiza podataka je uključila metode deskriptivne statistike (srednja vrednost, standardna devijacija, učestalost), kao i standardne parametrijske i neparametrijske testove za komparacije dve grupe (Studentov T test, Mann&ndash;Whitney U test, hikvadrat test). U fazi statističke analize međusobnih uticaja i povezanosti prikupljenih podataka kori&scaron;ćen je Pearsonov test korelacije. Sva testiranja sprovedena su na nivou statističke značajnosti p&lt;0,05. REZULTATI: Istraživanje je obuhvatilo 65 bolesnika, od kojih je 82% bilo mu&scaron;kog pola prosečne starosti 59 godina. 83% bolesnika su se izja&scaron;njavali kao pu&scaron;ači, dok je 69% bolesnika navelo da redovno koristi alkohol. Svim pacijentima je tokom hirur&scaron;kog lečenja OPK rađena disekcija vrata i to najče&scaron;čće selektivna disekcija vrata (91%). Kod 30 bolesnika je utvrđeno postojanje cervikalnih regionalnih metastaza na operativnom preparatu te su bolesnici podeljeni u dve grupe: sa prisustvom i bez prisustva metastaza u limfnim čvorovima vrata. Utvrđeno je da se ove dve grupe statistički značajno razlikuju u dubini invazije tumora i volumenu tumora. Utvrđeno je takođe da postoji statistički značajna korelacija između debljine tumora izmerene CT pregledom i debljine tumora izmerene svetlosnim mikroskopom. Dokazano je da dubina invazije tumora veća od 7mm i zapremina tumora veća od 4cm&sup3; predstavljaju prediktivni faktor za pojavu regionalnih cervikalnih metastaza. ZAKLjUČAK: Na osnovu istraživanja izvedeni su zaključci koji ukazuju na to da postoji statistički značajna korelacija između debljine tumora OPK izmerene CTpregledom i svetlosnim mikroskopom te se debljina tumora izmerena CT pregledom može koristiti za planiranje operativnog zahvata prilikom lečenja OPK. Dubina invazije tumora veća od 7mm i volumen tumora veći od 4 cm&sup3; predstavljaju prediktivni faktor za pojavu nodalnih cervikalnih metastaza te su značajni za određivanje stadijuma bolesti.</p> / <p>Oral cancer is the sixth most common malignant disease in the world which incidence varies based on geographic area. It represents 5% of all newly discovered malignant tumors annually and constitutes 14 % of all malignant tumors of head and neck. Squamous cell carcinoma is considered to be a type of oral cancer because more than 90 % of malignant tumors that occur in oral cavity are squamous cell carcinomas while other tumors (malignant tumor of minor salivary gland, lymphoma, sarcoma) rarely occur. Oral cancer is the cancer found in the following anatomic regions: mucosa of front two-thirds of the tongue, the floor of the mouth, cheeks, upper and lower gingiva, retromolar trigone as well as&nbsp; mucosa of soft and hard palates. Oral squamous cell carcinoma is most commonly localized in mucous membrane of the movable part of the tongue and floor of the mouth. Men are more affected than women (male to female ratio is 3:1) probably because of men&rsquo;s riskier behavior. It is most commonly diagnosed in the sixth and seventh decade of life (the median is 62 years old) although it has been diagnosed in patents younger than 45 in recent years. Risk factors of oral squamous cell carcinoma are well known. The major factor is tobacco smoking (the period of smoking is significant, it is also important to consider whether a patient smokes a pipe or cigarette, whether he/she chews tobacco as well as the period of abstinence). The mortality rate is believed to be directly related to the number of cigarettes smoked a day. An excessive use of alcohol has been reported in over 75% of patients with oral cancer. There is a synergistic effect of alcohol and cigarette consumption and long-term exposure to these risk factors results in &lsquo;field of cancerization&rsquo;, genetic instability and tumor development. Chromosome abnormalities, which are caused by DNA damage and include the change in genetic material of chromosomes, have been reported in patients with oral squamous cell carcinoma. One of the most common genetic abnormalities in patients with oral squamous cell carcinoma is a mutation of р53 gene which is located on a short arm of chromosome 17 and represents a tumor suppressor gene. Oral squamous cell carcinoma is not difficult to diagnose when it becomes symptomatic. The patient complains of pain, bleeding, otalgia, swallowing difficulties, decreased tongue mobility. The first symptom is rarely metastatic lymph node on the neck because patients either do not notice or ignore oral pathology. The oral cancer is diagnosed based on the detailed anamnesis, physical examination and pathohistological verification. The oral squamous cell carcinoma occurs in three clinical forms: exophytic, endophytic and infiltrative form. The gold standard for diagnosis of oral cancer is biopsy and pathohistological verification. However, in case of smaller changes, punch biopsy, incisional and excisional biopsies can also be applied. ТNМ staging system of AJCC (American Joint Committee on Cancer) is nowadays used for clinical staging of oral cancer and it is based on the data acquired by clinical examination and imaging methods. Not only is the staging itself important for communication between the doctors involved in treatment, but it is also important for standardization of prognosis. Т describes the size of primary tumor, N describes regional nodal spread and М describes distant metastasis. The treatment of histopathologically proven oral cancer requires multidisciplinary approach. The main treatment of oral squamous cell carcinoma is surgical treatment which involves ablative and reconstructive surgical treatment. The basic principle of ablative surgery for oral cancer is the resection of primary tumor with at least 1 cm negative surgical margins. Apart from tumor ablation surgical treatment also involves removal of regional lymph nodes on the neck. The aim of neck dissection is to remove clinically evident metastasis (therapeutic dissection) or to remove occult metastasis that are not clinically evident (elective dissection). The oral squamous cell carcinoma is the cancer with high mortality rate. The mortality rate is higher than the mortality rate for lymphoma, laryngeal cancer, testicular cancer and endocrine cancer. The five-year survival rate is directly related to the size of the tumor, presence of metastasis in regional lymph nodes and distant metastasis. The average three-year survival rate of the patients with oral cancer is 52% and the average five-year survival rate is 39%. These rates have not changed a lot over the years regardless of new knowledge and approaches in treatment of oral squamous cell carcinoma. The aims of the study are to determine whether there is a correlation between the depth of invasion of oral squamous cell carcinoma determined by computed tomography and light microscope and whether the invasion depth of OSCC and tumor volume can be predictive factors of development of regional cervical metastases in case of oral squamous cell carcinoma. The study covered 65 consecutive patients of both sexes who received treatment for oral cancer at the Clinic for Maxillofacial Surgery of the Clinical Center of Vojvodina. The diagnosis of oral cancer was established based on the anamnesis, physical examination and biopsies. The TNM &lsquo;staging&rsquo; of the cancer involved the examination of the patient&rsquo;s head and thorax by computed tomography (CT) which enabled us to obtain reliable data about the tumor size. After obtaining clinical findings and CT results, the patients&rsquo; treatment was planned based on their TNM status. A postoperative histopathological examination was performed by the same pathologist and the following parameters were determined: 1. Tumor size (2 dimensions) measured by CT and expressed in cm 2. Tumor thickness measured by CT and expressed in cm 3. Tumor size (2 diameters) on microscopic device and expressed in cm 4. Tumor thickness on microscopic device measured by light microscope and expressed in cm 5. Depth of tumor invasion on microscopic device measured by light microscope and expressed in cm 6. Tumor volume calculated based on the following formula: VT=&pi;/6 x maximum tumor diameter А x minimum tumor diameter B x depth of tumor invasion and expressed in cm&sup3; 7. The number of metastatic lymph nodes in the neck dissection 8. Total number of pathohistologically tested lymph nodes in the neck dissection. Upon collecting the planned material, statistical analysis of all data was carried out. The statistical analysis included the methods of descriptive statistics (mean value, standard deviation, frequency) and standard parametric and nonparametric tests for comparison of two groups (Student&rsquo;s T test, Whitney U test, chi-square test). The Pearson&rsquo;s Test of Correlation was used in the phase of statistical analysis of interaction effects and correlation of obtained data. All tests were performed at the level of statistical significance of p&lt;0.05. RESULTS: The study covered 65 patients, out of which 82% were male patients aged 59. 83% of patients said they smoked and 69% of patients stated that they consumed alcohol regularly. A neck dissection was performed in all patients during surgical treatment of OSCC and it was selective neck dissection (91%). Cervical regional metastasis was found in 30 patients so they were divided into two groups: the group of patients who had metastasis in the lymph nodes and the group of patients with no metastasis in lymph nodes of the neck. It was determined that there was a statistically significant difference in depth of invasion and tumor volume between these two groups. The statistically significant difference was also determined between the thickness of tumor measured by CT and thickness of tumor measured by light microscope. Moreover, the depth of invasion of tumor greater than 7mm and volume of tumor greater than 4cm&sup3; were proven to represent a predictive factor of development of regional cervical metastasis. The study results show that there is a statistically significant correlation between the thickness of OSCC tumor measured by CT and the thickness measured by light microscope, so the thickness of tumor measured by CT can be used for planning the surgery during the treatment of OSCC. The depth of tumor invasion greater than 7 mm and tumor volume greater than 4 cm&sup3; represent a predictive factor of development of cervical metastasis, which means that they are significant for determining the stage of disease.</p>

This diploma thesis deals with reduction of metal artifacts in CT data with submicron resolution. The first part of this thesis briefly describes x-ray computed tomography followed by the description of artifacts of tomographic images and existing approaches of the reduction of metal artifacts. In the second part proposed methods of reduction of metal artifacts and their implementation in Matlab programming environment are described. Finally functionality of algorithms is tested on a newly created database and the results are compared, evaluated and discussed.

X-Ray Computed Tomography is irreplaceable medical imaging system. Quantitative evaluation is day to day routine used for clean run of this imaging system. The master’s thesis is focused on quantitative evaluation of first and third generation X-Ray CT. First of all is about subjective and objective evaluation of space and energetic resolution. Space resolution is evaluated in space and frequency domain. Energetic resolution is represent by low contrast resolution method. Application “Kvantitativní hodnocení kvality CT RTG zobrazení” created for this thesis is used for creation of reconstruction image and quantitative evaluation. This application was created with consideration of its usage in subjects about image processing. The master’s thesis contains results of quantitative evaluation X-Ray CT created with this application and proposal of lab work.

The work deals with physical principles of X-ray generation and development of image during projection and projection reconstruction. A proposal of user’s application in a Matlab – Guide is given, which can be used as a laboratory exercise of the simulation of the projection- and projection image reconstruction. The computer program involves an evaluation of a X-ray quality of CT RTG ZS – quantitative assessment of spatial resolution and as well as the acquisition contrast as a function on an object size. The main aim of the work was the comparison of the acquisition contrast at various acquisition projection and projection-reconstruction parameters. Also, the work is illustrated by some results achieved.

Text in English / The destructive nature of conventional analytical techniques, coupled with the finite nature of ancient/historical artefacts, has long restricted technical examinations of museum collections, mainly due to ethical constraints. However, over the past few decades, the application of Non-Destructive Evaluation (NDE) techniques has become increasingly popular within the fields of archaeology and cultural heritage diagnostics. The application of such techniques has facilitated the examination of objects that have long remained uninvestigated. However, this positive development also held a slight drawback, in that researchers tend to now focus on technical analyses alone, while excluding more traditional means of analyses, such as comparative stylistic analysis and surface investigation. By employing a combination of stylistic analysis, visual surface investigation (by means of SLR photography and digital microscopy) and nuclear imaging (by means of Microfocus X-Ray Computed Tomography), the thesis sets out to justify the application of mixed methodologies as part of a more holistic integrated authentication approach. Thus stated, the thesis presents a mixed-methodological approach towards the analysis of selected metal objects from the Ditsong National Museum of Cultural History in Pretoria, South Africa. The objects under investigation include a small collection of ancient Egyptian bronze statuettes, a Samurai helmet (kabuto) and mask (menpó), a European gauntlet, and an Arabian dagger (jambiya/khanjar). While all the objects are curated as part of the museum‘s archaeology and military history collections, the exact production dates, manufacturing techniques and areas of origin remain a mystery. By using a combination of techniques, the thesis aims to identify diagnostic features that can be used to shed light on their relative age, culturo-chronological framework and, by extension, their authenticity. / Old Testament and Ancient Near Eastern Studies / D. Litt. et Phil.(Ancient Near Eastern Studies)

No description available.

Application of smart curing concept called internal curing (IC) is the most promising strategy for mitigating autogenous shrinkage and related early-age cracking in cement-based materials with low water-to-cement ratio. There are still many theoretical and practical questions that need to be answered before IC could become a standard method. Many of these questions concern the most appealing of water-regulating additives for IC called Superabsorbent Polymers (SAP). The clear linkage between SAP material properties, the moment of water release and the effect on autogenous shrinkage is still missing, which blocks formulating recommendations for use of particular potential IC agents in concrete construction. In this treatise various aspects that are decisive for effectiveness of IC in mitigating autogenous shrinkage were examined. The choice of materials was purposefully limited to two compositions of Ultra-High Performance Concrete (UHPC), one fine-grained and one coarse-grained mixture, and one particular, in-depth characterized SAP. The objectives of examination which shaped the final experimental programme were: assessment of IC agent absorption capacity, specification of periods of water migration from fresh concrete mixture into SAP and from SAP back into hardening concrete, determination of effect of SAP addition on cement hydration, evaluation of IC influence on and determination of start of effective autogenous shrinkage and, finally, assessment of autogenous shrinkage with selfsame IC agent but for different matrices. Ideally, description of the mechanisms behind the action of IC at different stages of concrete life and reasoning of differences observed for the UHPCs under investigation had to be provided. First, the main components of the system – UHPC and SAP material – were characterized as to their suitability for IC application. Special attention was paid to the material properties which affect water transport. Usage of different testing methods was necessary here and included: testing with ESEM, FT-IR, tea-bag test, sol fraction content examination and X-ray computed tomography (for SAP) as well as air content measurement and various methods for characterization of the porosity and other features of the microstructure. The observed delay in the start of pozzolanic reactions in case of fine-grained UHPC was rather surprising, but, under consideration of porosity, shed new light on permeability of young UHPC. The work at hand revealed numerous methods that can be used for studying the absorption capacity of polymers, but hardly representative for the behaviour of those polymers within concrete matrix. Because of its general availability and the relatively robust testing procedure, it was decided to focus on possibilities and limitations of using tea-bag test for evaluation of absorption capacity of SAP. New interpretation of tea-bag test results was deduced which enabled assessment of maximum absorption capacity of SAP from measurement of consistency of concrete before and after modification with IC. Influence of IC on hydration process was revealed by using two non-destructive methods, in particular ultrasonic measurement and concrete temperature record. It could be shown that the ionic polymer exhibits complex effects including retardation and acceleration of individual chemical processes. Additionally, X-ray computed tomography (CT) and instrumented ring tests were performed in order to understand scientific significance of the characteristic event appearing during shrinkage measurements, taken as time-zero (= starting point for evaluation of autogenous shrinkage data). Linkage of time-zero with certain phenomenon, e.g., changes of the SAP particles volume or specific value of yield stress, but not with final set, was suggested for the future investigations. By using two setups based on corrugated tube protocol it was possible to register and compare autogenous shrinkage of both UHPCs without and with modification by IC. The effectiveness of IC was shown to be dependent on the matrix in which IC was implemented. This was related to the observed changes in pore percolation that resulted from different absorption behaviour of SAP in the two UHPCs under investigation. Furthermore, the effect of fibres on effectiveness of IC was discussed. Description and discussion of mechanisms behind IC was supported by measurement of capillary pressure, total shrinkage tests with simultaneous mass loss measurement, free autogenous shrinkage tests and the CT measurement. Valuable source of information was furthermore the in-depth literature review. The most appealing finding of the work and the biggest paradox revealed was high efficiency of IC in mitigating autogenous shrinkage and simultaneously appearance of stage where very clear reverse in mode of polymer volume change was observed. This suggests partial reabsorption of water initially released. This puts interpretation of operative shrinkage mechanisms and ones standing behind IC effect in a new perspective. / Die innere Nachbehandlung (Internal Curing – IC) ist die derzeit aussichtsreichste Strategie, um das in zementgebundenen Baustoffen mit niedrigen Wasser/Zement-Werten ausgeprägt auftretende autogene Schwinden wirksam zu verringern und die damit einhergehende Rissbildung in jungem Beton zu vermeiden. Vor einer breiten baupraktischen Anwendung des IC sind noch viele offene Fragen zu beantworten. Die meisten dieser Fragen betreffen die derzeit interessanteste Klasse von wasserregulierenden Stoffen für das IC – die superabsorbierenden Polymere (SAP). Von entscheidender Bedeutung ist hier der noch weitgehend unerforschte Zusammenhang zwischen den Materialeigenschaften der SAP, dem Zeitpunkt der Wasserabgabe und der Auswirkung auf das autogene Schwinden. In der vorliegenden Arbeit werden verschiedene Einflussfaktoren auf die Wirksamkeit von SAP zur Verringerung des autogenen Schwindens untersucht. Für die Experimente wurde ein feinkörniger und ein grobkörniger ultra-hochfester Beton (UHPC) sowie ein schon detailliert charakterisiertes SAP genutzt. Das experimentelle Programm wurde auf folgende Untersuchungsziele ausgerichtet: Absorptionsvermögen der SAP, Zeitfenster der Wassermigration aus dem Frischbeton in das SAP sowie vom SAP in den erhärtenden Beton, autogenes Schwindmaß sowie effektiver Beginn des autogenen Schwindens. Ziel der Arbeiten ist die Beschreibung der Mechanismen, die IC zugrundliegen – und dies zu verschiedenen Betonaltern und unter Berücksichtigung der an den untersuchten UHPC beobachteten Unterschiede. Bei der Charakterisierung der Hauptkomponenten des betrachteten Systems – UHPC und SAP – wurde auf die Materialeigenschaften fokussiert, die den Wassertransport beeinflussen. Dazu wurden u. a. folgende Untersuchungsmethoden angewendet: ESEM, FT-IR, Teebeuteltest, Sol-Fraction Test, Röntgentomographie (für SAP) sowie verschiedene Verfahren zur Charakterisierung der Poren im Beton. Im feinkörnigen UHPC wurde überraschenderweise ein verzögerter Beginn der puzzolanischen Reaktion festgestellt, der bei Berücksichtigung der vorliegenden Porosität zu einer Neubewertung der Permeabilität von UHPC in jungem Alter führte. In der vorliegenden Arbeit werden verschiedene Methoden zur Beschreibung des Wasserabsorptionsvermögens von SAP benannt, deren Aussagekraft bei Anwendung dieser Polymere im Beton aber sehr eingeschränkt ist. Aufgrund seiner einfachen Verfügbarkeit und Robustheit wurde daher der Teebeutetest zur Bestimmung der Wasserabsorption des SAP genutzt. Die Wasserabsorption der SAP im Beton wurde durch Gegenüberstellung von Konsistenzmessungen am Beton vor und nach Zugabe von SAP und Ergebnissen der Teebeuteltest abgeschätzt. Der Einfluss des IC auf die Hydratation wurde zerstörungsfrei mit Ultraschall- und Betontemperaturmessungen erfasst. Auf dieser Grundlage konnten Hypothesen zu den komplexen Wechselwirkungen zwischen ionischem Polymer und der Beschleunigung oder Verzögerung einzelner chemischer Prozesse formuliert werden. Mit Hilfe von instrumentierten Ringversuchen und X-ray Computertomographie wurden die Auswirkungen des IC mit SAP auf das autogene Schwinden, den Aufbau von Zwangsspannungen bei behindertem Schwinden und Time-Zero diskutiert. Dabei konnte ein Zusammenhang zwischen Time-Zero und verschiedenen Phänomenen, wie z. B. Volumenänderung des SAP oder der Fließgrenze des erhärtenden Betons, nicht aber zum Ende des Erstarrens aufgezeigt werden. Das autogene Schwinden beider untersuchter UHPC (jeweils mit und ohne IC) wurde mit Hilfe von Corrugated Tube-Versuchen gemessen. Es konnte gezeigt werden, dass wie Wirksamkeit des IC von der Betonzusammensetzung sowie der in den UHPC infolge Wechselwirkungen mit den SAP verschieden ausgebildeten Porenstruktur der Matrix abhängt. Weiterhin konnte ein Einfluss von Faserzugaben auf die Wirksamkeit des IC gezeigt werden. Die Beschreibung und Diskussion der Mechanismen des IC wurde durch Messungen des Kapillardrucks, des Gesamtschwindens, des freien autogenen Schwindens, des Masseverlustes und Computertomographie unterstützt. Eine wichtige Erkenntnisquelle war zudem die umfangreich gesichtete und diskutierte Literatur. Das interessanteste und zugleich paradoxe Ergebnis der Untersuchungen ist die Tatsache, dass die bei Einsatz von SAP beobachtete Verringerung des autogenen Schwindens eindeutig mit einer zeitgleichen Umkehr der Volumenänderung der SAP einhergeht: die bis dahin dominierende Wasserabgabe geht in eine erneute Wasseraufnahme über. Dies stellt die Interpretation der Triebkräfte des Schwindens und die dem IC zugrundliegenden Mechanismen in einen neuen Zusammenhang.