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Solid organ transplantation is today an established form of treatment for end-stage organ disease. Monitoring of graft function and pharmacological therapy constitutes a maze of clinical observations and histological evaluations of biopsy specimens; with the biopsy results playing a decisive role. The aims of this doctoral research were to investigate the feasibility of detecting acute rejection of transplanted organs and monitoring the effect of anti-rejection treatment, with the use of ultrasmall superparamagnetic iron oxide particles (USPIO) and magnetic resonance (MR) imaging with a clinical MR scanner. Allogeneic and syngeneic heterotopic heart transplantations were performed in rats. Three different-sized USPIO were given to one allogeneic and one syngeneic group. The change in MR signal intensity (SI) over time was measured. An increase in SI was interpreted as damage to micro vessels due to the pronounced inflammatory reaction caused by acute rejection, which led to leakage of USPIO into the tissue. A decrease in SI was interpreted as normal vascular structure, since USPIO normally remains in the intravascular space. The same method, using one of the previously tested USPIO, was used in a treatment study in which acute rejection in transplanted rats was induced and subsequently treated. An attempt was also made to detect presence of macrophages in an acutely rejecting graft, since this cell type plays an important role in the acute rejection process; this was done by testing the ability of macrophages to phagocytose the UPSIO compound. In permeability studies with MR imaging all three USPIO tested discriminated between rejecting and non-rejecting grafts without any overlap of the groups. Factors that contributed to the ability to distinguish between grafts were the size and half-life of the particle. We were also able to monitor effects of anti-rejection treatment by studying the vascular permeability of USPIO and MR imaging. We did not succeed in detecting macrophages in the rejecting grafts with USPIO and MR imaging. This thesis presents a novel approach to detection of acute rejection of transplanted organs and to monitoring the effects of anti-rejection treatment using different USPIO contrast agents and MR imaging in a clinical MR scanner.

Persistent hyperplastic primary vitreous (PHPV), a developmental cause of leukocoria, is due to incomplete regression of the fetal blood supply to the eye. We report the MRI features of PHPV of the dorsal type to facilitate differential diagnosis from other causes of leukocoria, namely retinoblastoma, which may have major therapeutic consequences.

Thalamus is a structure in the brain that controls states of awakeness, sleeping and consciousness. Neurodegenerative diseases like multiple sclerosis (MS) cause damage to nerve cells including cells in the thalamus. With segmentation of thalamus in magnetic resonance (MR) images we could calculate volume of thalamus and relate it to the disability caused by the disease. In this thesis we developed an automated segmentation method based on co-registration of atlases, which contain thalamus segmentations, onto the target MR image and fusion of the atlases. The dataset of atlases was created by manually segmenting the MR images. Automated segmentation of the thalamus with affine and B-spline based registration and majority voting atlas fusion yielded best quality according to quantitative evaluation. The evaluation was based on T1-weighted MR images of 87 subjects with MS and 88 healthy subjects. We also investigated the relationships between the (normalized) thalamic volumes and the clinical and demographic data and compared the volume between MS and healthy subjects. Similarly to previous reports in the literature the thalamic volumes decreased with increasing age, extended disease duration, and increasing functional disability of the MS patients. On the other hand, the thalamic volumes increased with years of education and results of the cognitive memory tests. By measuring the volume of thalamus we could thus enable higher quality of life of the MS patients as a result of the possibility of earlier and more potent treatment. Talamus je struktura v možganih, ki nadzira stanja budnosti, spanja in zavesti. Nevrodegenerativne bolezni, kot je multipla skleroza (MS), prizadenejo živčne celice, torej tudi talamus. Z razmejitvijo talamusa v magnetnoresonančnih (MR) slikah bi lahko izmerili njegov volumen in tako ugotovili povezavo med volumnom talamusa in stopnjo napredovanja multiple skleroze. V nalogi smo razvili avtomatski postopek za razmejitev talamusa na podlagi poravnave atlasov, tj. slik z danimi razmejitvami talamusa, na ciljno MR sliko in zlivanjem poravnanih atlasov. Zbirko atlasov smo pripravili na podlagi ročnih razmejitev. Avtomatska razmejitev talamusa z uporabo poravnave na osnovi afine preslikave in preslikave z B-zlepki ter zlivanja s postopkom glasovanja z večino je bila glede na kvantitativno vrednotenje najbolj kakovostna. Za analizo smo uporabili T1-utežene MR slike 87-ih oseb z boleznijo MS in 88-ih zdravih oseb. Nazadnje smo poiskali povezave med izračunanimi (normiranimi) volumni talamusa in kliničnimi ter demografskimi podatki bolnikov ter primerjali volumne med MS bolniki in zdravimi. Po pričakovanjih volumen talamusa pada s staranjem, daljšim trajanjem bolezni in višanjem splošne stopnje funkcionalne prizadetosti bolnikov, medtem ko narašča z daljšim trajanjem izobraževanja in višjimi rezultati kognitivnih testov delovanja spomina. Z merjenjem volumna talamusa bi tako lahko omogočili višjo kvaliteto življenja bolnikov z MS, predvsem zaradi možnosti zgodnejšega in bolj potentnega zdravljenja.

Abstract copyright UK Data Service and data collection copyright owner.BackgroundThe Labour Force Survey (LFS) is a unique source of information using international definitions of employment and unemployment and economic inactivity, together with a wide range of related topics such as occupation, training, hours of work and personal characteristics of household members aged 16 years and over. It is used to inform social, economic and employment policy. The Annual Population Survey, also held at the UK Data Archive, is derived from the LFS.The LFS was first conducted biennially from 1973-1983, then annually between 1984 and 1991, comprising a quarterly survey conducted throughout the year and a 'boost' survey in the spring quarter. From 1992 it moved to a quarterly cycle with a sample size approximately equivalent to that of the previous annual data. Northern Ireland was also included in the survey from December 1994. Further information on the background to the QLFS may be found in the documentation.The UK Data Service also holds a Secure Access version of the QLFS (see below); household datasets; two-quarter and five-quarter longitudinal datasets; LFS datasets compiled for Eurostat; and some additional annual Northern Ireland datasets.LFS DocumentationThe documentation available from the Archive to accompany LFS datasets largely consists of the latest version of each user guide volume alongside the appropriate questionnaire for the year concerned (the latest questionnaire available covers July-September 2022). Volumes are updated periodically, so users are advised to check the latest documents on the ONS Labour Force Survey - User Guidance pages before commencing analysis. This is especially important for users of older QLFS studies, where information and guidance in the user guide documents may have changed over time.LFS response to COVID-19From April 2020 to May 2022, additional non-calendar quarter LFS microdata were made available to cover the pandemic period. The first additional microdata to be released covered February to April 2020 and the final non-calendar dataset covered March-May 2022. Publication then returned to calendar quarters only. Within the additional non-calendar COVID-19 quarters, pseudonymised variables Casenop and Hserialp may contain a significant number of missing cases (set as -9). These variables may not be available in full for the additional COVID-19 datasets until the next standard calendar quarter is produced. The income weight variable, PIWT, is not available in the non-calendar quarters, although the person weight (PWT) is included. Please consult the documentation for full details.Occupation data for 2021 and 2022 data filesThe ONS has identified an issue with the collection of some occupational data in 2021 and 2022 data files in a number of their surveys. While they estimate any impacts will be small overall, this will affect the accuracy of the breakdowns of some detailed (four-digit Standard Occupational Classification (SOC)) occupations, and data derived from them. Further information can be found in the ONS article published on 11 July 2023: Revision of miscoded occupational data in the ONS Labour Force Survey, UK: January 2021 to September 2022.2024 ReweightingIn February 2024, reweighted person-level data from July-September 2022 onwards were released. Up to July-September 2023, only the person weight was updated (PWT23); the income weight remains at 2022 (PIWT22). The 2023 income weight (PIWT23) was included from the October-December 2023 quarter. Users are encouraged to read the ONS methodological note of 5 February, Impact of reweighting on Labour Force Survey key indicators: 2024, which includes important information on the 2024 reweighting exercise.End User Licence and Secure Access QLFS dataTwo versions of the QLFS are available from UKDS. One is available under the standard End User Licence (EUL) agreement, and the other is a Secure Access version. The EUL version includes country and Government Office Region geography, 3-digit Standard Occupational Classification (SOC) and 3-digit industry group for main, second and last job (from July-September 2015, 4-digit industry class is available for main job only).The Secure Access version contains more detailed variables relating to:age: single year of age, year and month of birth, age completed full-time education and age obtained highest qualification, age of oldest dependent child and age of youngest dependent childfamily unit and household: including a number of variables concerning the number of dependent children in the family according to their ages, relationship to head of household and relationship to head of familynationality and country of originfiner detail geography: including county, unitary/local authority, place of work, Nomenclature of Territorial Units for Statistics 2 (NUTS2) and NUTS3 regions, and whether lives and works in same local authority district, and other categories;health: including main health problem, and current and past health problemseducation and apprenticeship: including numbers and subjects of various qualifications and variables concerning apprenticeshipsindustry: including industry, industry class and industry group for main, second and last job, and industry made redundant fromoccupation: including 5-digit industry subclass and 4-digit SOC for main, second and last job and job made redundant fromsystem variables: including week number when interview took place and number of households at addressother additional detailed variables may also be included.The Secure Access datasets (SNs 6727 and 7674) have more restrictive access conditions than those made available under the standard EUL. Prospective users will need to gain ONS Accredited Researcher status, complete an extra application form and demonstrate to the data owners exactly why they need access to the additional variables. Users are strongly advised to first obtain the standard EUL version of the data to see if they are sufficient for their research requirements. This study was deposited in 2008, as a result of the move from seasonal to calendar quarters for the QLFS, and the reweighting process to 2007-2008 population figures. It combines data from previously-available QLFS seasonal quarter datasets. The depositor has advised that small revisions to the data may have been made during this process, but they should not be significant. Main Topics:The QLFS questionnaire comprises a 'core' of questions which are included in every survey, together with some 'non-core' questions which vary from quarter to quarter.The questionnaire can be split into two main parts. The first part contains questions on the respondent's household, family structure, basic housing information and demographic details of household members. The second part contains questions covering economic activity, education and health, and also may include a few questions asked on behalf of other government departments (for example the Department for Work and Pensions and the Home Office). Until 1997, the questions on health covered mainly problems which affected the respondent's work. From that quarter onwards, the questions cover all health problems. Detailed questions on income have also been included in each quarter since 1993. The basic questionnaire is revised each year, and a new version published, along with a transitional version that details changes from the previous year's questionnaire. Four sampling frames are used. See documentation for details. Face-to-face interview Telephone interview The first interview is conducted face-to-face, and subsequent interviews by telephone where possible.

El trastorno por deficit de atención con hiperactividad (TDAH) es considerado uno de los trastornos psiquiátricos infantiles con mayor prevalencia, careacterizado por síntomas de inatención, hiperactividad e impulsividad. Hasta hace poco, se pensanba que los síntomas mejoraban con la edad, pero recientemente existe evidencia de que los síntomas del trastorno pueden prevalecer hasta la edad adulta. Un estudio reciente indicó que un 35% de los casos continuaban presentando el trastorno en la adultez, afectando aproximadamente entre un 3-7% de la población adulta. A pesar de que el substrato neurobiológico del TDAH no se conoce con exactitud, estudios geneticos, preclínicos y clínicos apuntan a que podría tratarse de alteraciones dopaminergicas y/o noradrenérgicas. Alteraciones en la actividad neural y el menor volumen de sustancia gris que se ha encontrado en estos pacientes en regiones relacionadas a la dopamina también corroboran dichos deficits. Adultos diagnosticados con TDAH suelen presentar deficits neuropsicológicos en cuanto a memoria de trabajo, atención y control inhibotorio. El modelo de doble vía de Sonuga Barke implica por lo menos dos endofenotipos, relativamente independientes pero no excluyentes el uno del otro. El primero se asocia más a deficits a nivel ejecutivo como el control inhibitorio, mientras que el segundo se realciona a lo que alteraciones motivaciones, principalmente la anticipación de la recompensa. Este modelo explica le heteroenidad del TDAH en términos de déficits cognitivos y motivacionales disociables, los cuales pueded afectar a algunos pacientes pero no a otros. Es importante señalar que recientemente se ha sugerido que el procesameinto temporal podría consituir un tecer componente nueropsicológicodisociabl del TDAH. Déficits en cuanto al procesamiento temporal se están estudiando en TDAH, y además, se ha evaluado su posible relación con la impulsividad, síntoma importante de este trastorno. A pesar de la influencia que los procesos motivaciones podrían tener en el funcionamiento cognitivo, pocos estudios han centrado en el substrato neuronal de los sistemas de motivación y temporales, y su implicación en la fisiopatología del TDAH. Por tanto, analizamos las imágenes RMf de 20 pacientes adultos con TDAH, no medicados y subtipo combinado, así como de 25 sujetos controles. Los datos se utilizaron para identificar y comparar la activación durante un paradigma de recompensa y discriminación temporal. El paradigma incluyó la prescencia de distractores durante la tarea para evaluar atención. Los resultados del análisis por regiones de interés indicó menor activación en el cerebelo izquierdo y derecho durante la tarera de recompensa/discriminación temporal en el grupo con TDAH. El cerebelo es una región implicada en alteraciones estructurales y funcionales en TDAH, y recientemente también se ha señalado su possible implicación como mediador en tareas de procesamiento temporal. Los análisis de whole-brain también inidcaron menor activación en el giro temporal superior, el cerebelo izquierdo y derecho, el giro fusiforme, el giro de Heschl, y el giro medio occipital en los pacientes. Contrariamente, se observó una mayor activación en los pacientes en el giro frontal inferior derecho y en el giro parietal superior izquierdo. Adicionalmente, los análisis por regiones de interés también mostraron menor actividad neural en ralación al estíimulo del distractor en el grupo con TDAH en la corteza prefrontal dorsolateral y en el giro precentral. En los análisis de whole-brain también se observó una menor activación en el giro postcentral izquierdo, el giro temporal izquierdo y el giro frontal izquierdo. Finalmente, se observó un aumento en la activación en los pacientes con TDAH en la corteza orbitofrontal derecha. Nuestros resultados aportan evidencia de que el procesamiento temporal, junto con procesos cognitivos como la atención, así como los procesos motivacionales relacionados con la recompensa, podrían representar un tercer componente neuropsicológico afectado en el TDAH. ADHD, conceived as one of the most prevalent childhood psychiatric disorders, is characterized by inattention, hyperactivity and impulsivity symptoms and estimate to affect 5% of worldwide population. Until recently, symptoms were thought to ameliorate with age. However, a recent 10 year follow-up study indicated that 35% of paediatric patients still meeting ADHD diagnostic criteria and it's been estimated that ADHD affects between 3 and 7% of adult population. Even thought the exact neurobiological substrate of ADHD still unclear, genetic, preclinical and clinical studies point to dopaminergic and/or noradrenergic alterations. Neural activity and grey matter volume decreases in dopamine related regions also corroborate such deficits. Adults diagnosed with this disorder are likely to neuropsychological deficits involving working memory, attention and inhibitory control. The multiple pathway model proposed by Sonuga-Barke implicates at least two relatively independent but not mutually exclusiv endophenotypes; those involving an executive functioning disruption such as inhibition control, and those more related with motivational system abnormalities, basically reward anticipation. Therefore, this model explains neuropsychological heterogeneity of ADHD in terms of dissociable cognitive and motivational deficits, each affecting some but not other patients. Importantly, it is been suggested that temporal processing might constitute a third dissociable neuropsychological component of ADHD. Recently, timing processing deficits are being studied in ADHD, and, furthermore, such abnormalities have been related with impulsiveness, a core symptom of ADHD. In spite of the influence that motivational and timing processes might have on cognitive functioning, only a few studies have focused on the neural substrate underpinning the motivational and timing systems and, specifically, their role in ADHD pathophysiology. Therefore, we analyzed functional magnetic resonance images (fMRI) of 20 un-medicated, combined, adult ADHD subjects and 25 healthy controls. Date sets were used to identify and compare the brain activation during a reward/time discrimination paradigm. The paradigm also included distractors during the task, in order to evaluate attention processes. Our results from the Regions of interest (ROIs) analysis indicated decreased brain activation in left and right cerebellum during the task that as compared to the control group. The cerebellum is key area of structural and functional abnormalities in ADHD, and, recently it has been implicated as one important mediator in time discrimination. Furthermore, whole brain analysis indicated decreased brain activity in right superior temporal gyrus, right left cerebellum, right fusiform gyrus, right Heschl's gyrus and left occipital middle gyrus in ADHD group as compared to controls. The opposite contrast showed increased activation levels in right frontal inferior gyrus and left superior parietal gyrus in the patients group. Additionally, ROIs analysis also showed reduced activity in relation to the distractor stimulus in the ADHD group in left DLPFC and the left precentral gyrus. The whole-brain analysis also shoewed a cluster of reduced activity located in the left post central gyrus, left inferior temporal gyrus and left inferior frontal gyrus. In the opposite contrast, we observed increased brain activity in the right orbitofrontal cortex in the patients group. Our results provide evidence that temporal processes, in addition to cognitve (i.e., attention) and motivational/emotional domains, might be a third dissociable neuropsychological component that affects ADHD.

Introducción: se mantiene el debate sobre qué tipos de intervenciones para la recuperación del ictus ofrecen mejores resultados para el paciente. Objetivo: evaluar el efecto de una intervención integral durante seis meses sobre la recuperación funcional en pacientes con ictus. Métodos: la muestra estuvo compuesta por 42 participantes con ictus: un grupo experimental (N = 22) con una media de edad de 52,68 años (DE = 14,39) que recibió una intervención integral, intensiva y multidisciplinar, y un grupo control (N = 20) con una media de edad de 56,20 años (DE = 14,82) que no recibió este tipo de intervención. Se valoraron los siguiente índices de severidad del ictus: Escala de Coma de Glasgow, Escala Canadiense, estancia en Unidad de Cuidados Intensivos, signos de enclavamiento uncal, signos de hipertensión endocraneal, volumen del hematoma/área isquémica, desplazamiento de línea media, necesidad de cirugía y tiempo total de hospitalización. Ambos grupos eran equivalentes en estos índices de gravedad. El grado de funcionalidad fue medido con la aplicación de la escala Functional Independence Measure and Functional Assessment Measure. Esta prueba se aplicó al inicio de la intervención y 6 meses después. Resultados: se observó una evolución positiva en ambos grupos en todas las áreas de la escala. La intervención integral y un menor tiempo total de hospitalización se relacionaron con una mejor recuperación funcional en el ictus. Conclusiones: se sugiere la necesidad de realizar estrategias de rehabilitación integral en los pacientes con ictus. Introduction: debate is currently underway about what types of stroke recovery interventions are more beneficial for patients. Objective: evaluate the effect of a six-month comprehensive intervention on the functional recovery of stroke patients. Methods: the study sample was 42 stroke patients: an experimental group (N = 22), mean age 52.68 years (SD = 14.39), who received a comprehensive intensive multidisciplinary intervention, and a control group (N = 20), mean age 56.20 years (SD = 14.82), who did not receive this type of intervention. The following stroke severity indices were applied: Glasgow Coma Scale, Canadian Scale, intensive care unit stay, uncal latching signs, endocranial hypertension signs, hematoma volume / ischemic area, midline displacement, need for surgery and total hospital stay time. These severity indices were similar in the two groups. Degree of functionality was gauged with the scales Functional Independence Measure and Functional Assessment Measure. This test was applied at the start of the intervention and 6 months later. Results: both groups had a positive evolution in all the areas of the scale. The comprehensive intervention and a shorter total hospital stay were associated to better functional recovery from stroke. Conclusions: the need is suggested to implement comprehensive rehabilitation strategies in stroke patients.

Tyrimo tikslas. Išsėtinė sklerozė (IS) yra neurodegeneracinis sutrikimas, greitai sukeliantis fizinę negalią. Depresijos epizodas (DE) yra dažniausias psichikos sutrikimas, per visą gyvenimą pasireiškiantis kas antram sergančiajam išsėtine skleroze ir lemiantis psichinę negalią. Dėl šių priežasčių sergantieji išsėtine skleroze susilaukia vis didesnio medikų, mokslininkų ir visuomenės dėmesio. Tačiau jų pačių požiūris, kokias veiklos sritis labiausiai pažeidžia išsėtinė sklerozė ir kokie veiksniai galėtų padėti veiksmingiau gydyti išsėtinę sklerozę, nepakankamai išsamiai išanalizuotas. Šio tyrimo tikslas- įvertinti sergančiųjų išsėtine skleroze požiūrį, ar liga trukdo jų socialinei, buitinei, darbinei veiklai ir šeimos gyvenimui, ką reikėtų pagerinti, kad išsėtinės sklerozės gydymas būtų veiksmingesnis bei nustatyti ryšius su depresijos epizodu. Pacientai ir tyrimo metodai. Tyrime, trukusiame 36 mėnesius, dalyvavo 135 ambulatoriškai ir 135 KMUK Neurologijos klnikos stacionare gydomi vyresni nei 18 metų pacientai (69,3 proc. moterų, 30,7 proc. vyrų, amžiaus vidurkis- 42,42±11,71 m.), sergantys išsėtine skleroze. Tyrimo metu naudota modifikuota anketa įvertinti, ar išsėtinė sklerozė trukdo sergančiųjų socialinei, buitinei ir darbinei veiklai bei 12 pasiūlymų, ką, tiriamųjų nuomone, reikėtų pagerinti, kad išsėtinės sklerozės gydymas būtų veiksmingesnis. Depresijos epizodo pasireiškimas vertintas remiantis TLK-10 klasifikacija. Tyrimų duomenų analizė atlikta naudojant "SPSS 15.0 for Windows" statistinę programą. Tyrimo rezultatai. Depresijos epizodas pasireiškė 20,7 proc. respondentų ir vienodai dažnai pasireiškė ir moterims, ir vyrams. Depresijos epizodo pasireiškimo šansas buvo 7,2 karto didesnis tiems pacientams, kurie nurodė, kad išsėtinė sklerozė trukdo jų šeimos gyvenimui. [...].

The correct diagnosis of epilepsy leads to an appropriate treatment.The first step is to distinguish epileptic seizures from nonepileptic attacks, and to make a precise seizure diagnosis and classification. The next step is to identify the etiology or basic disorders underlying the epilepsy by physical and neurologic examinations, laboratory tests, including EEGs and neuroradiologic examinations. Although the EEG is the most important laboratory examination for the diagnosis of epilepsy, limitations of EEG interpretations must be recognized.A syndromic classification of the patients, to determine whether they fit known syndromes, should be attempted. If patients do not match a described syndrome, a neurobiologic approach, utilizing genetic, neurophysiological, and neuropharmacologic knowledge, alternatively provides useful information to understand the neurobiologic background of epilepsy.Both approaches have advantages and disadvantages for diagnosing and treating epilepsy. Both approaches can be used interchangeably with patients with seizure disorders, depending upon their condition. The epilepsy diagnosis, etiology, and seizure-type diagnosis should be reevaluated when seizure control is insufficient with first- and second-line antiepileptic drugs.