965 resultados para diagnostic value


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Aberrant glycosylation of proteins is a hallmark of tumorigenesis, and could provide diagnostic value in cancer detection. Human saliva is an ideal source of glycoproteins due to the relatively high proportion of glycosylated proteins in the salivary proteome. Moreover, saliva collection is non-invasive, technically straightforward and the sample collection and storage is relatively easy. Although, differential glycosylation of proteins can be indicative of disease states, identification of differential glycosylation from clinical samples is not trivial. To facilitate salivary glycoprotein biomarker discovery, we optimised a method for differential glycoprotein enrichment from human saliva based on lectin magnetic bead arrays (saLeMBA). Selected lectins from distinct reactivity groups were used in the saLeMBA platform to enrich salivary glycoproteins from healthy volunteer saliva. The technical reproducibility of saLeMBA was analysed with LC-MS/MS to identify the glycosylated proteins enriched by each lectin. Our saLeMBA platform enabled robust glycoprotein enrichment in a glycoprotein- and lectin-specific manner consistent with known protein-specific glycan profiles. We demonstrated that saLeMBA is a reliable method to enrich and detect glycoproteins present in human saliva.

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Välikorvaleikkauksiin usein liittyvän välikorvan ja kuuloluuketjun kirurgisen rekonstruktion tavoitteena on luoda olosuhteet, jotka mahdollistavat hyvän kuulon sekä välikorvan säilymisen tulehduksettomana ja ilmapitoisena. Välikorvan rekonstruktiossa on käytetty implanttimateriaaleina perinteisesti potilaan omia kudoksia sekä tarvittaessa erilaisia hajoamattomia biomateriaaleja, mm. titaania ja silikonia. Ongelmana biomateriaalien käytössä voi olla bakteerien adherenssi eli tarttuminen vieraan materiaalin pintaan, mikä saattaa johtaa biofilmin muodostumiseen. Tämä voi aiheuttaa kroonisen, huonosti antibiootteihin reagoivan infektion kudoksessa, mikä usein käytännössä johtaa uusintaleikkaukseen ja implantin poistoon. Maitohappo- ja glykolihappopohjaiset biologisesti hajoavat polymeerit ovat olleet kliinisessä käytössä jo vuosikymmeniä. Niitä on käytetty erityisesti tukimateriaaleina mm. ortopediassa sekä kasvo- ja leukakirurgiassa. Niitä ei ole toistaiseksi käytetty välikorvakirurgiassa. Korvan kuvantamiseen käytetään ensisijaisesti tietokonetomografiaa (TT). TT-tutkimuksen ongelmana on potilaan altistuminen suhteellisen korkealle sädeannokselle, joka kasvaa kumulatiivisesti, jos kuvaus joudutaan toistamaan. Väitöskirjatyö selvittää uuden, aiemmin kliinisessä työssä rutiinisti lähinnä hampaiston ja kasvojen alueen kuvantamiseen käytetyn rajoitetun kartiokeila-TT:n soveltuvuutta korvan alueen kuvantamiseen. Väitöskirjan kahdessa ensimmäisessä osatyössä tutkittiin ja verrattiin kahden kroonisia ja postoperatiivisia korvainfektioita aiheuttavan bakteerin, Staphylococcus aureuksen ja Pseudomonas aeruginosan, in vitro adherenssia titaanin, silikonin ja kahden eri biohajoavan polymeerin (PLGA) pintaan. Lisäksi tutkittiin materiaalien albumiinipinnoituksen vaikutusta adherenssiin. Kolmannessa osatyössä tutkittiin eläinmallissa PLGA:n biokompatibiliteettia eli kudosyhteensopivuutta kokeellisessa välikorvakirurgiassa. Chinchillojen välikorviin istutettiin PLGA-materiaalia, eläimiä seurattiin, ja ne lopetettiin 6 kk:n kuluttua operaatiosta. Biokompatibiliteetin arviointi perustui kliinisiin havaintoihin sekä kudosnäytteisiin. Neljännessä osatyössä tutkittiin kartiokeila-TT:n soveltuvuutta korvan alueen kuvantamiseen vertaamalla sen tarkkuutta perinteisen spiraali-TT:n tarkkuuteen. Molemmilla laitteilla kuvattiin ohimo- eli temporaaliluita korvan alueen kliinisesti ja kirurgisesti tärkeiden rakenteiden kuvantumisen tarkkuuden arvioimiseksi. Viidennessä osatyössä arvioitiin myös operoitujen temporaaliluiden kuvantumista kartiokeila-TT:ssa. Bakteeritutkimuksissa PLGA-materiaalin pintaan tarttui keskimäärin korkeintaan saman verran tai vähemmän bakteereita kuin silikonin tai titaanin. Albumiinipinnoitus vähensi bakteeriadherenssia merkitsevästi kaikilla materiaaleilla. Eläinkokeiden perusteella PLGA todettiin hyvin siedetyksi välikorvassa. Korvakäytävissä tai välikorvissa ei todettu infektioita, tärykalvon perforaatioita tai materiaalin esiin työntymistä. Kudosnäytteissä näkyi lievää tulehdusreaktiota ja fibroosia implantin ympärillä. Temporaaliluutöissä rajoitettu kartiokeila-TT todettiin vähintään yhtä tarkaksi menetelmäksi kuin spiraali-TT välikorvan ja sisäkorvan rakenteiden kuvantamisessa, ja sen aiheuttama kertasäderasitus todettiin spiraali-TT:n vastaavaa huomattavasti vähäisemmäksi. Kartiokeila-TT soveltui hyvin välikorvaimplanttien ja postoperatiivisen korvan kuvantamiseen. Tulokset osoittavat, että PLGA on välikorvakirurgiaan soveltuva, turvallinen ja kudosyhteensopiva biomateriaali. Biomateriaalien pinnoittaminen albumiinilla vähentää merkittävästi bakteeriadherenssia niihin, mikä puoltaa pinnoituksen soveltamista implanttikirurgiassa. Kartiokeila-TT soveltuu korvan alueen kuvantamiseen. Sen tarkkuus kliinisesti tärkeiden rakenteiden osoittamisessa on vähintään yhtä hyvä ja sen potilaalle aiheuttama sädeannos pienempi kuin nykyisen korva-spiraali-TT:n. Tämä tekee menetelmästä spiraali-TT:aa potilasturvallisemman vaihtoehdon erityisesti, jos potilaan tilanne vaatii seurantaa ja useampia kuvauksia, ja jos halutaan kuvata rajoitettuja alueita uni- tai bilateraalisesti.

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Prostate cancer (PCa) is the most commonly diagnosed non-skin cancer and second leading cause of cancer-related death of men in developed countries. Measurement of prostate specific antigen (PSA) is a very sensitive method for diagnosing and monitoring of prostate cancer (PCa), but the specificity needs improvement. Measurements of different molecular forms of PSA have been shown to improve differentiation between PCa and benign prostatic diseases. However, accurate measurement of some isoforms has not been achieved in previous assays. The aim of the present study was to develop new assays that reliably measure enzymatically active PSA, PSA-α1-chymotryposin (PSA-ACT) and PSA-α1-protease inhibitor (PSA-API), and to evaluate their diagnostic value. Double-label immunofluorometric assays using a novel monoclonal antibody (MAb) and another antibody to either free PSA (fPSA) or total PSA (tPSA) were developed and used to measure PSA-ACT and fPSA or tPSA at the same time. These assays provide enough sensitivity for measurement of PSA-ACT in sera with low PSA levels. The results obtained confirmed that proportion of PSA-ACT to tPSA (%PSA-ACT) was as useful as proportion of fPSA to tPSA (%fPSA) for discrimination between PCa and benign prostatic hyperplasia (BPH). We developed an immunoassay for detection of PSA-API based on proximity ligation, which improved assay sensitivity 10-fold compared with conventional assays. Our results confirmed previous findings that the PSA-API level is somewhat lower in men with than without PCa, and the combination of %fPSA and proportion of PSA-API to tPSA (%PSA-API) provides diagnostic improvement compared with either method alone. Assays based on this principle should be applicable to other immunoassays in which the nonspecific background is a problem. An immunopeptidometric sandwich assay (IPMA) was developed to measure the enzymatically active PSA. This assay showed high specificity, but sensitivity was not good enough for measurement of PSA concentrations in the gray zone, 2-10 µg/L, in which tPSA does not efficiently differentiate between PCa and BPH. We further developed a solid-phase proximity ligation immunoassay, which provided a 10-fold improvement in sensitivity. This proof of concept study shows that peptides reacting with proteins are potentially useful for sensitive and specific measurement of protein variants for which specific MAbs cannot be obtained.

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Purpose In the oncology population where malnutrition prevalence is high, more descriptive screening tools can provide further information to assist triaging and capture acute change. The Patient-Generated Subjective Global Assessment Short Form (PG-SGA SF) is a component of a nutritional assessment tool which could be used for descriptive nutrition screening. The purpose of this study was to conduct a secondary analysis of nutrition screening and assessment data to identify the most relevant information contributing to the PG-SGA SF to identify malnutrition risk with high sensitivity and specificity. Methods This was an observational, cross-sectional study of 300 consecutive adult patients receiving ambulatory anti-cancer treatment at an Australian tertiary hospital. Anthropometric and patient descriptive data were collected. The scored PG-SGA generated a score for nutritional risk (PG-SGA SF) and a global rating for nutrition status. Receiver operating characteristic curves (ROC) were generated to determine optimal cut-off scores for combinations of the PG-SGA SF boxes with the greatest sensitivity and specificity for predicting malnutrition according to scored PG-SGA global rating. Results The additive scores of boxes 1–3 had the highest sensitivity (90.2 %) while maintaining satisfactory specificity (67.5 %) and demonstrating high diagnostic value (AUC = 0.85, 95 % CI = 0.81–0.89). The inclusion of box 4 (PG-SGA SF) did not add further value as a screening tool (AUC = 0.85, 95 % CI = 0.80–0.89; sensitivity 80.4 %; specificity 72.3 %). Conclusions The validity of the PG-SGA SF in chemotherapy outpatients was confirmed. The present study however demonstrated that the functional capacity question (box 4) does not improve the overall discriminatory value of the PG-SGA SF.

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ABSTRACT Idiopathic developmental disorders (DDs) affect ~1% of the population worldwide. This being a considerable amount, efforts are being made to elucidate the disease mechanisms. One or several genetic factors cause 30-40% of DDs, and only 10% are caused by environmental factors. The remaining 50% of DD patients go undiagnosed, mostly due to a lack of diagnostic techniques. The cause in most undiagnosed cases is though to be a genetic factor or a combination of genetic and environmental factors. Despite the surge of new technologies entering the market, their implementation into diagnostic laboratories is hampered by costs, lack of information about the expected diagnostic yield, and the wide range of selection. This study evaluates new microarray methods in diagnosing idiopathic DDs, providing information about their added diagnostic value. Study I analysed 150 patients by array comparative genomic hybridization (array CGH, 44K and 244K), with a subsequent 18% diagnostic yield. These results are supported by other studies, indicating an enourmous added diagnostic value of array CGH, compared with conventional cytogenetic analysis. Nevertheless, 80% of the patients remained undiagnosed in Study I. In an effort to diagnose more patients, in Study IV the resolution was increased from 8.9 Kb of the 244K CGH array to 0.7 Kb, by using a single-nucleotide polymorphism (SNP) array. However, no additional pathogenic changes were detected in the 35 patients assessed, and thus, for diagnostic purposes, an array platform with ca 9 Kb resolution appears adequate. The recent vast increase in reports of detected aberrations and associated phenotypes has enabled characterization of several new syndromes first based on a common aberration and thereafter by delineation of common clinical characteristics. In Study II, a familial deletion at 9q22.2q22.32 with variable penetrance was described. Despite several reports of aberrations in the adjacent area at 9q associated with Gorlin syndrome, the patients in this family had a unique phenotype and did not present with the syndrome. In Study III, a familial duplication of chromosome 6p22.2 was described. The duplication caused increased expression of an important enzyme of the γ-aminobutyric acid (GABA) degradation pathway, causing oxidative stress of the brain, and thus, very likely, the mild mental retardation of these patients. These two case studies attempted to pinpoint candidate genes and to resolve the pathogenic mechanism causing the clinical characteristics of the patients. Presenting rare genetic and clinical findings to the international science and medical community enables interpretation of similar findings in other patients. The added value of molecular karyotyping in patients with idiopathic DD is evident. As a first line of testing, arrays with a median resolution of at least 9 Kb should be considered and further characterization of detected aberrations undertaken when possible. Diagnostic whole-exome sequencing may be the best option for patients who remain undiagnosed after high-resolution array analysis.

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Real world biological systems such as the human brain are inherently nonlinear and difficult to model. However, most of the previous studies have either employed linear models or parametric nonlinear models for investigating brain function. In this paper, a novel application of a nonlinear measure of phase synchronization based on recurrences, correlation between probabilities of recurrence (CPR), to study connectivity in the brain has been proposed. Being non-parametric, this method makes very few assumptions, making it suitable for investigating brain function in a data-driven way. CPR's utility with application to multichannel electroencephalographic (EEG) signals has been demonstrated. Brain connectivity obtained using thresholded CPR matrix of multichannel EEG signals showed clear differences in the number and pattern of connections in brain connectivity between (a) epileptic seizure and pre-seizure and (b) eyes open and eyes closed states. Corresponding brain headmaps provide meaningful insights about synchronization in the brain in those states. K-means clustering of connectivity parameters of CPR and linear correlation obtained from global epileptic seizure and pre-seizure showed significantly larger cluster centroid distances for CPR as opposed to linear correlation, thereby demonstrating the superior ability of CPR for discriminating seizure from pre-seizure. The headmap in the case of focal epilepsy clearly enables us to identify the focus of the epilepsy which provides certain diagnostic value. (C) 2013 Elsevier Ltd. All rights reserved.

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Complex biological systems such as the human brain can be expected to be inherently nonlinear and hence difficult to model. Most of the previous studies on investigations of brain function have either used linear models or parametric nonlinear models. In this paper, we propose a novel application of a nonlinear measure of phase synchronization based on recurrences, correlation between probabilities of recurrence (CPR), to study seizures in the brain. The advantage of this nonparametric method is that it makes very few assumptions thus making it possible to investigate brain functioning in a data-driven way. We have demonstrated the utility of CPR measure for the study of phase synchronization in multichannel seizure EEG recorded from patients with global as well as focal epilepsy. For the case of global epilepsy, brain synchronization using thresholded CPR matrix of multichannel EEG signals showed clear differences in results obtained for epileptic seizure and pre-seizure. Brain headmaps obtained for seizure and preseizure cases provide meaningful insights about synchronization in the brain in those states. The headmap in the case of focal epilepsy clearly enables us to identify the focus of the epilepsy which provides certain diagnostic value. Comparative studies with linear correlation have shown that the nonlinear measure CPR outperforms the linear correlation measure. (C) 2014 Elsevier Ltd. All rights reserved.

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In the present paper the external and internal morphology of the shrimp Pleoticus muelleri (Bate), is described in detail. Special attention is given to those features which are of diagnostic value or which are significant for a fuller understanding of the biology of this species. The major portion of the paper deals with the description of the cephalopereion, pleon and telson and its appendages, as well as the nervous, respiratory, circulatory, digestive, excretory and reproductive systems. Special attention is given to the digestive system, the stomodaeal apparatus and sexual dimorphism. The relations between form and function of several organs and systems are pointed out. A study is made of the development of the gonads, the sexual cycle in males and females; the variations found in relative weight and size are described. The phylogenetical jposition of the Penaeidae, the genera of the subfamily Solenoceridae and of P. muelleri are discussed. (PDF contains 72 pages)

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Simulation of disorders of respiratory mechanics shown by spirometry provides insight into the pathophysiology of disease but some clinically important disorders have not been simulated and none have been formally evaluated for education. We have designed simple mechanical devices which, along with existing simulators, enable all the main dysfunctions which have diagnostic value in spirometry to be simulated and clearly explained with visual and haptic feedback. We modelled the airways as Starling resistors by a clearly visible mechanical action to simulate intra- and extra-thoracic obstruction. A narrow tube was used to simulate fixed large airway obstruction and inelastic bands to simulate restriction. We hypothesized that using simulators whose action explains disease promotes learning especially in higher domain educational objectives. The main features of obstruction and restriction were correctly simulated. Simulation of variable extra-thoracic obstruction caused blunting and plateauing of inspiratory flow, and simulation of intra-thoracic obstruction caused limitation of expiratory flow with marked dynamic compression. Multiple choice tests were created with questions allocated to lower (remember and understand) or higher cognitive domains (apply, analyse and evaluate). In a cross-over design, overall mean scores increased after 1½ h simulation spirometry (43-68 %, effect size 1.06, P < 0.0001). In higher cognitive domains the mean score was lower before and increased further than lower domains (Δ 30 vs 20 %, higher vs lower effect size 0.22, P < 0.05). In conclusion, the devices successfully simulate various patterns of obstruction and restriction. Using these devices medical students achieved marked enhancement of learning especially in higher cognitive domains.

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A família Nephtyidae é uma das mais frequentes em habitats costeiros e marinhos de todo o mundo. São organismos errantes típicos de sedimentos arenosos e lodosos, ocorrendo frequentemente no domínio costeiro até 100 m de profundidade, e mais raramente em profundidades batiais e abissais. As primeiras espécies descritas foram o Nephtys caeca (Fabricius, 1780) e o N. ciliata (O. F. Müller, 1789), ambas atribuídas inicialmente ao género Nereis e posteriormente transferidas para o género Nephtys por Savigny, em 1818. A família Nephtyidae foi criada em 1851 por Grube para o género Nephtys Cuvier, 1817. No âmbito desta tese é feito um estudo taxonómico e filogenético da família Nephtyidae. O estudo filogenético inclui dados morfológicos e moleculares de 24 taxa representantes dos cinco géneros da família, Nephtys Cuvier, 1817, Aglaophamus Kinberg, 1866, Micronephthys (Friedrich, 1939), Inermonephtys Fauchald, 1967 e Dentinephtys Imajima e Takeda, 1987. A análise evidenciou dois grandes grupos correspondentes aos dois principais géneros, Aglaophamus e Nephtys. Duas espécies do género Nephtys (N. pulchra e N. australiensis) são transferidas para o género Aglaophamus, e consequentemente são propostas novas diagnoses para os géneros. O género Dentinephtys é sinonimizado com Nephtys e um novo género, Bipalponephtys, é descrito para acomodar as espécies Nephtys cornuta, N. danida e Micronephthys neotena. As relações filogenéticas entre os géneros são discutidas. Do estudo taxonómico resultou a revisão da família Nephtyidae para o Sul da Europa (entre o Canal da Mancha e o Mediterrâneo), com a descrição de uma nova espécie, Inermonephtys foretmontardoi. A espécie Micronephthys maryae é sinonimizada com M. stammeri. Para cada espécie são incluídas notas sobre a sua ecologia bem como a distribuição geográfica e batimétrica. São propostas novas diagnoses para os géneros do Sul da Europa bem como uma chave de identificação taxonómica para as espécies desta região. Após uma exaustiva revisão bibliográfica da família, e da observação de material museológico relativo a 44 espécies, foi compilada uma lista completa para a família de 128 espécies, distribuídas por cinco géneros (57 Nephtys, 53 Aglaophamus, sete Micronephthys, oito Inermonephtys e três Bipalponephtys), na qual são incluídas sinonímias e considerações taxonómicas para cada espécie. A espécie Nephtys serrata é sinonimizada com N. serratifolia. São apresentados as distribuições geográficas e batimétricas das diferentes espécies e notas sobre o seu habitat. São também incluídas tabelas de identificação com as principais características taxonómicas das espécies. O valor diagnóstico dos caracteres morfológicos é discutido. Vários problemas taxonómicos são realçados, indicando a necessidade de revisões adicionais para 23 espécies. Este trabalho realça a existência de vários problemas taxonómicos e filogenéticos dentro da família Nephtyidae, podendo ser considerado como a base para estudos futuros. Análises filogenéticas adicionais incluindo dados morfológicos e moleculares de um maior número de espécies vão certamente conduzir a uma melhor avaliação do estatuto e relações entre os géneros dentro da família.

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This thesis reports the application of metabolomics to human tissues and biofluids (blood plasma and urine) to unveil the metabolic signature of primary lung cancer. In Chapter 1, a brief introduction on lung cancer epidemiology and pathogenesis, together with a review of the main metabolic dysregulations known to be associated with cancer, is presented. The metabolomics approach is also described, addressing the analytical and statistical methods employed, as well as the current state of the art on its application to clinical lung cancer studies. Chapter 2 provides the experimental details of this work, in regard to the subjects enrolled, sample collection and analysis, and data processing. In Chapter 3, the metabolic characterization of intact lung tissues (from 56 patients) by proton High Resolution Magic Angle Spinning (HRMAS) Nuclear Magnetic Resonance (NMR) spectroscopy is described. After careful assessment of acquisition conditions and thorough spectral assignment (over 50 metabolites identified), the metabolic profiles of tumour and adjacent control tissues were compared through multivariate analysis. The two tissue classes could be discriminated with 97% accuracy, with 13 metabolites significantly accounting for this discrimination: glucose and acetate (depleted in tumours), together with lactate, alanine, glutamate, GSH, taurine, creatine, phosphocholine, glycerophosphocholine, phosphoethanolamine, uracil nucleotides and peptides (increased in tumours). Some of these variations corroborated typical features of cancer metabolism (e.g., upregulated glycolysis and glutaminolysis), while others suggested less known pathways (e.g., antioxidant protection, protein degradation) to play important roles. Another major and novel finding described in this chapter was the dependence of this metabolic signature on tumour histological subtype. While main alterations in adenocarcinomas (AdC) related to phospholipid and protein metabolisms, squamous cell carcinomas (SqCC) were found to have stronger glycolytic and glutaminolytic profiles, making it possible to build a valid classification model to discriminate these two subtypes. Chapter 4 reports the NMR metabolomic study of blood plasma from over 100 patients and near 100 healthy controls, the multivariate model built having afforded a classification rate of 87%. The two groups were found to differ significantly in the levels of lactate, pyruvate, acetoacetate, LDL+VLDL lipoproteins and glycoproteins (increased in patients), together with glutamine, histidine, valine, methanol, HDL lipoproteins and two unassigned compounds (decreased in patients). Interestingly, these variations were detected from initial disease stages and the magnitude of some of them depended on the histological type, although not allowing AdC vs. SqCC discrimination. Moreover, it is shown in this chapter that age mismatch between control and cancer groups could not be ruled out as a possible confounding factor, and exploratory external validation afforded a classification rate of 85%. The NMR profiling of urine from lung cancer patients and healthy controls is presented in Chapter 5. Compared to plasma, the classification model built with urinary profiles resulted in a superior classification rate (97%). After careful assessment of possible bias from gender, age and smoking habits, a set of 19 metabolites was proposed to be cancer-related (out of which 3 were unknowns and 6 were partially identified as N-acetylated metabolites). As for plasma, these variations were detected regardless of disease stage and showed some dependency on histological subtype, the AdC vs. SqCC model built showing modest predictive power. In addition, preliminary external validation of the urine-based classification model afforded 100% sensitivity and 90% specificity, which are exciting results in terms of potential for future clinical application. Chapter 6 describes the analysis of urine from a subset of patients by a different profiling technique, namely, Ultra-Performance Liquid Chromatography coupled to Mass Spectrometry (UPLC-MS). Although the identification of discriminant metabolites was very limited, multivariate models showed high classification rate and predictive power, thus reinforcing the value of urine in the context of lung cancer diagnosis. Finally, the main conclusions of this thesis are presented in Chapter 7, highlighting the potential of integrated metabolomics of tissues and biofluids to improve current understanding of lung cancer altered metabolism and to reveal new marker profiles with diagnostic value.

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Purpose: First, to report ECU subsheath's normal MRI appearance and the findings in athletic injuries. Second, to determine the best MRI sequence for diagnosis. Methods and materials: Sixteen patients (13 males, 3 females, mean age 30.3 years) with ECU subsheath's athletic injuries sustained between January 2003 and June 2009 were retrospectively reviewed. Wrist MRI studies were performed on 1.5-T units and consisted of at least transverse T1 and STIR sequences in pronation, and FS Gd T1 in pronation and supination. Two radiologists assessed the following items, in consensus: injury type (A to C according to Inoue), ECU tendon stability, and associated lesions (ulnar head oedema, extensor retinaculum injury, ECU tendinosis and tenosynovitis). Then, each reader independently rated the sequences' diagnostic value: 0 = questionable, 1 = suggestive, 2 = certain. Follow-up studies were present in 8 patients. ECU subsheath's normal visibility (medial, central and lateral parts) was retrospectively evaluated in 30 consecutive control MRI studies. Results: FS Gd T1 sequences in supination (1.63) and pronation (1.59) were the most valuable for diagnosis, compared to STIR (1.22) and T1 (1). The study group included 9 type A, 1 type B and 6 type C injuries. There were trends towards diminution in pouches' size, signal intensity and enhancement in follow-up studies, along with tendon stabilization within the ulnar groove. In control studies, ECU subsheath's visibility in medial, central and lateral parts were noted in 66.7-80%, 63.3-80% and 30-50% respectively. Conclusion: ECU subsheath's athletic injuries are visible on 1.5-T MRI studies. FS Gd T1 sequences in supination and pronation are the most valuable.

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Hepatocellular Carcinoma (HCC) is a major healthcare problem, representing the third most common cause of cancer-related mortality worldwide. Chronic infections with Hepatitis B virus (HBV) and/or Hepatitis C virus (HCV) are the major risk factors for the development of HCC. The incidence of HBV -associated HCC is in decline as a result of an effective HBV vaccine; however, since an equally effective HCV vaccine has not yet been developed, there are 130 million HCV infected patients worldwide who are at a high-risk for developing HCC. Because reliable parameters and/or tools for the early detection of HCC among high-risk individuals are severely lacking, HCC patients are always diagnosed at a late stage where surgical solutions or effective treatment are not possible. Using urine as a non-invasive sample source, two different approaches (proteomic-based and genomic-based approaches) were pursued with the common goal of discovering potential biomarker candidates for the early detection of HCC among high-risk chronic HCV infected patients. Urine was collected from 106 HCV infected Egyptian patients, 32 of whom had already developed HCC and 74 patients who were diagnosed as HCC-free at the time of initial sample collection. In addition to these patients, urine samples were also collected from 12 healthy control individuals. Total urinary proteins, Trans-renal nucleic acid (Tr-NA) and microRNA (miRNA) were isolated from urine using novel methodologies and silicon carbide-loaded spin columns. In the first, "proteomic-based", approach, liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) was used to identify potential candidates from pooled urine samples. This was followed by validating relative expression levels of proteins present in urine among all the patients using quantitative real time-PCR (qRT-PCR). This approach revealed that significant over-expression of three proteins: DJ-1, Chromatin Assembly Factor-1 (CAF-1) and 11 Moemen Abdalla HCC Biomarkers Heat Shock Protein 60 (HSP60), were characteristic events among HCC-post HCV infected patients. As a single-based HCC biomarker, CAF-1 over-expression identified HCC among HCV infected patients with a specificity of 90%, sensitivity of 66% and with an overall diagnostic accuracy of 78%. Moreover, the CAF-lIHSP60 tandem identified HCC among HCV infected patients with a specificity of 92%, sensitivity of 61 % and with an overall diagnostic accuracy of 77%. In the second genomic-based approach, two different approaches were processed. The first approach was the miRNA-based approach. The expression levels of miRNAs isolated from urine were studied using the Illumina MicroRNA Expression Profiling Assay. This was followed by qRT-PCR-based validation of deregulated expression of identified miRNA candidates among all the patients. This approach shed the light on the deregulated expression of a number of miRNAs, which may have a role in either the development of HCC among HCV infected patients (i.e. miR-640, miR-765, miR-200a, miR-521 and miR-520) or may allow for a better understanding of the viral-host interaction (miR-152, miR-486, miR-219, miR452, miR-425, miR-154 and miR-31). Moreover, the deregulated expression of both miR-618 and miR-650 appeared to be a common event among HCC-post HCV infected patients. The results of the search for putative targets of these two miRNA suggested that miR-618 may be a potent oncogene, as it targets the tumor-suppressor gene Low density lipoprotein-related protein 12 (LPR12), while miR-650 may be a potent tumor-suppressor gene, as it is supposed to downregulate the TNF receptor-associated factor-4 (TRAF4) oncogene. The specificity of miR-618 and miR-650 deregulated expression patterns for the early detection of HCC among HCV infected patients was 68% and 58%, respectively, whereas the sensitivity was 64% and 72%, respectively. When the deregulated expression of both miRNAs was combined as a tandem biomarker, the specificity and the sensitivity were 75% and 58% respectively. 111 Moemen Abdalla HCC Biomarkers In the second, "Trans-renal nucleic acid-based", approach, the urinary apoptotic nucleic acid (uaNA) levels of 70ng/mL or more were found to be a good predictor of HCC among chronic HCV infected patients. The specificity and the sensitivity of this diagnostic approach were 76% and 86%, respectively, with an overall diagnostic value of 81 %. The uaNA levels positively correlated to HCC disease progression as monitored by epigenetic changes of a panel of eight tumor-suppressor genes (TSGs) using methylation-sensitive PCR. Moreover, the pairing of high uaNA levels (:::: 70 ng/mL) and CAF-1 over-expreSSIOn produced a highly specific (l 00%) multiple-based HCC biomarker with an acceptable sensitivity of 64%, and with a diagnostic accuracy of 82%. In comparison to the previous pairing, the uaNA levels (:::: 70 ng/mL) in tandem with HSP60 over-expression was less specific (89%) but highly sensitive (72%), resulting in a diagnostic accuracy of 64%. The specificities of miR-650 deregulated expression in combination with either high uaNA content or HSP 60 over-expression were 82% and 79%, respectively, whereas, the sensitivities of these combinations were 64% and 58%, respectively. The potential biomarkers identified in this study compare favorably with the diagnostic accuracy of the a-fetoprotein levels test, which has a specificity of 75%, sensitivity of 68% and an overall diagnostic accuracy of 70%. Here we present an intriguing study which shows the significance of using urine as a noninvasive sample source for the identification of promising HCC biomarkers. We have also introduced new techniques for the isolation of different urinary macromolecules, especially miRNA, from urine. Furthermore, we strongly recommend the potential biomarkers indentified in this study as focal points of any future research on HCC diagnosis. A larger testing pool will determine if their use is practical for mass population screening. This explorative study identified potential targets that merit further investigation for the development of diagnostically accurate biomarkers isolated from 1-2 mL urine samples that were acquired in a non-invasive manner.

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Indwelling electromyography (EMG) has great diagnostic value but its invasive and often painful characteristics make it inappropriate for monitoring human movement. Spike shape analysis of the surface electromyographic signal responds to the call for non-invasive EMG measures for monitoring human movement and detecting neuromuscular disorders. The present study analyzed the relationship between surface and indwelling EMG interference patterns. Twenty four males and twenty four females performed three isometric dorsiflexion contractions at five force levels from 20% to maximal force. The amplitude measures increased differently between electrode types, attributed to the electrode sensitivity. The frequency measures were different between traditional and spike shape measures due to different noise rejection criteria. These measures were also different between surface and indwelling EMG due to the low-pass tissue filtering effect. The spike shape measures, thought to collectively function as a means to differentiate between motor unit characteristics, changed independent of one another.

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La leucémie lymphoblastique aigüe (LLA) est une maladie génétique complexe. Malgré que cette maladie hématologique soit le cancer pédiatrique le plus fréquent, ses causes demeurent inconnues. Des études antérieures ont démontrées que le risque à la LLA chez l’enfant pourrait être influencé par des gènes agissant dans le métabolisme des xénobiotiques, dans le maintient de l’intégrité génomique et dans la réponse au stress oxydatif, ainsi que par des facteurs environnementaux. Au cours de mes études doctorales, j’ai tenté de disséquer davantage les bases génétiques de la LLA de l’enfant en postulant que la susceptibilité à cette maladie serait modulée, au moins en partie, par des variants génétiques agissant dans deux voies biologiques fondamentales : le point de contrôle G1/S du cycle cellulaire et la réparation des cassures double-brin de l’ADN. En utilisant une approche unique reposant sur l’analyse d’une cohorte cas-contrôles jumelée à une cohorte de trios enfants-parents, j’ai effectué une étude d’association de type gènes/voies biologiques candidats. Ainsi, j’ai évaluer le rôle de variants provenant de la séquence promotrice de 12 gènes du cycle cellulaire et de 7 gènes de la voie de réparation de l’ADN, dans la susceptibilité à la LLA. De tels polymorphismes dans la région promotrice (pSNPs) pourraient perturber la liaison de facteurs de transcription et mener à des différences dans les niveaux d’expression des gènes pouvant influencer le risque à la maladie. En combinant différentes méthodes analytiques, j’ai évalué le rôle de différents mécanismes génétiques dans le développement de la LLA chez l’enfant. J’ai tout d’abord étudié les associations avec gènes/variants indépendants, et des essaies fonctionnels ont été effectués afin d’évaluer l’impact des pSNPs sur la liaison de facteurs de transcription et l’activité promotrice allèle-spécifique. Ces analyses ont mené à quatre publications. Il est peu probable que ces gènes de susceptibilité agissent seuls; j’ai donc utilisé une approche intégrative afin d’explorer la possibilité que plusieurs variants d’une même voie biologique ou de voies connexes puissent moduler le risque de la maladie; ces travaux ont été soumis pour publication. En outre, le développement précoce de la LLA, voir même in utero, suggère que les parents, et plus particulièrement la mère, pourraient jouer un rôle important dans le développement de cette maladie chez l’enfant. Dans une étude par simulations, j’ai évalué la performance des méthodes d’analyse existantes de détecter des effets fœto-maternels sous un design hybride trios/cas-contrôles. J’ai également investigué l’impact des effets génétiques agissant via la mère sur la susceptibilité à la LLA. Cette étude, récemment publiée, fût la première à démontrer que le risque de la leucémie chez l’enfant peut être modulé par le génotype de sa mère. En conclusions, mes études doctorales ont permis d’identifier des nouveaux gènes de susceptibilité pour la LLA pédiatrique et de mettre en évidence le rôle du cycle cellulaire et de la voie de la réparation de l’ADN dans la leucémogenèse. À terme, ces travaux permettront de mieux comprendre les bases génétiques de la LLA, et conduiront au développement d’outils cliniques qui amélioreront la détection, le diagnostique et le traitement de la leucémie chez l’enfant.