No description available.

Cerebral blood flow (CBF) measures are central to the investigation of ischemic strokes, spreading depressions, functional and neuronal activation. Laser Speckle Contrast Imaging (LSCI) is an optical imaging technique that has been used to obtain CBF measures in vivo at high spatial and temporal resolutions, by quantifying the localized spatial blurring of backscattered coherent light induced by blood flow. Despite being widely used for biomedical applications, LSCI's critical limitations such as its tendency to underestimate large flow changes and its inability to accurately estimate CBF through a thinned skull have not been overcome. This dissertation presents a new Multi Exposure Speckle Imaging (MESI) technique that combines a new instrument and mathematical model to overcome these limitations. Additionally, in a pilot clinical study, an adapted neurosurgical microscope was used to obtain intra-operative LSCI images of CBF in humans. The MESI instrument accurately estimates experimental constants by imaging backscattered speckles over a wide range of the camera's exposure durations. The MESI mathematical model helps account for light that has scattered from both static and moving particles. In controlled flow experiments using tissue simulating phantoms, the MESI technique was found to estimate large changes in flow accurately and the estimates of flow changes were found to be unaffected by the presence of static particles in these phantoms. In an in vivo experiment in which the middle cerebral artery in mice was occluded to induce ~100% reduction in CBF, not only was the reduction in CBF accurately estimated by the MESI technique but these estimates of CBF changes were found to be unaffected by the presence of a thinned skull. The validity of statistical models used to derive the MESI mathematical model was confirmed using in vivo dynamic light scattering (DLS) measurements of CBF in mice. The MESI technique's potential to estimate absolute values of CBF in vivo was demonstrated by comparing CBF estimates obtained using the MESI technique to DLS measurements. The MESI technique's ability to measure CBF changes quantitatively through a thinned skull makes it particularly useful in chronic and long term studies leading to the development of better, more accurate stroke models. / text

Ce travail de thèse a permis, dans un premier temps, de mettre en évidence de nouveaux grandsréarrangements dans trois pathologies étudiées au laboratoire : la mucoviscidose, la pancréatitechronique et l’hémochromatose. En particulier, ces travaux ont permis de trouver de nouveaux CNVs(Copy Number Variations) pathologiques dans le gène CFTR (Cystic Fibrosis Transmembraneconductance Regulator), de mieux comprendre les mécanismes d’un remaniement complexe dansPRSS1 (Protease Serine 1) et d’aider à caractériser finement un réarrangement dans HFE(Hemochromatosis). Ces études ont donc servi de preuve de concept pour l’utilisation de puces à ADN àl’échelle d’un gène et dans des zones difficiles car riches en séquences répétées.Dans un second temps, la recherche de facteurs de susceptibilité génétiques aux infarctus cérébraux(AICs) du sujet jeune a été réalisée chez 168 cas et 200 témoins âgés de moins de 40 ans. Dans notrepopulation, l’hypertension, les migraines, le tabac, et la prise de stupéfiants sont des facteurs de risqueimportants, multipliant respectivement par 35, 3,8, 4 et 2,8 le risque d’AIC. Notre étude pangénomiquepar CGH-array (Comparative Genomic Hybridization-array) a mis en évidence 98 régionspolymorphiques dans le génome humain. Parmi elles, la délétion d’une partie du gène NOTCH2, pourraitjouer un rôle protecteur dans la survenue des AICs (OR=0,11 [0,01-0,87] ; p=0,013) mais qui ne dépassepas le seuil fixé par la correction de Bonferroni). Ce travail a également mis en évidence environ 400CNVs rares, dont deux récurrents chez les cas, l'un portant les gènes CRELD2 (cysteine-rich with EGFlikedomains 2) et AGL12 (asparagine-linked glycosylation 12, alpha-1, 6-mannosyltransferase) (p=0,02)et le deuxième situé en 5’ du gène VBP1 (von Hippel-Lindau binding protein 1) (p=0,04). Enfin, uneapproche gènes candidats a été effectuée sur les gènes NOTCH2 et ALOX5AP (5-lipoxygenaseactivating protein) sans donner de résultats significatifs. Ceci a également été réalisé sur les mutationsprincipales de trois gènes de la coagulation (Facteur II, Facteur V Leiden et MTHFR). Une associationsignificative a été mise en évidence entre la C677T du gène MTHFR (5,10-methyltetrahydrofolate) et lesinfarctus cérébraux du sujet jeune (OR=2,39, p=0,02 pour le génotype TT). Ce travail de thèse a permisde confirmer l’existence de facteurs de risque environnementaux et génétiques déjà connus mais surtoutd’émettre de nouvelles hypothèses génétiques dans la survenue des AICs du sujet jeune. / The use of locus-specific array-CGH (Comparative Genomic Hybridization) has allowed us to detect largerearrangements in three pathologies of our laboratory: cystic fibrosis, chronic pancreatitis andhemochromatosis. We successfully observed new pathological CNV (Copy Number Variations) in theCFTR (Cystic Fibrosis Transmembrane conductance Regulator) gene and characterized complex eventsin PRSS1 (Protease Serine 1) and HFE (Hemochromatosis) genes, showing that the use of thistechnique is possible even in regions with high sequence homologies.We also confirmed that hypertension, migraine, tobacco and drugs are high significant risk factors forischemic strokes (IS) in young population (under 40 years) (OR=35, 3.8, 4 and 2.8, respectively). Then,we tried to identify new genetic susceptibility loci using a pangenomic approach. Among the 98 copynumber polymorphisms (CNP) observed, an interstitial NOTCH2 deletion is candidate for a protective rolein IS (OR=0.11 [0.01-0.87] ; p=0.013 before Bonferonni correction). We also observed approximately 400uncommon CNV, two of them being particularly reccurent in patients: a 22q13.31 duplication containingCRELD2 (cysteine-rich with EGF-like domains 2) and AGL12 (asparagine-linked glycosylation 12, alpha-1, 6-mannosyltransferase) genes (p=0.02) and a Xq28 deletion localised in the 5’ region of the VBP1 (vonHippel-Lindau binding protein 1) gene (p=0.04). We also applied a candidate-gene approach onNOTCH2, ALOX5AP (5-lipoxygenase activating protein) and coagulation genes (Factor II, Factor VLeiden and MTHFR). A significant association was found for the C677T in the MTHFR gene (5,10-methyltetrahydrofolate) and young ischemic strokes (OR=2.39, p=0.02 for TT genotype). In conclusion,this study confirmed the implication of environmental and genetic factors in ischemic strokes before 40years and suggests new genetic risk factors for IS.

Stroke is the 5th leading cause of death in the U.S. with 130,000 deaths and around 800,000 affected annually. Currently, there is a significant disconnect between basic stroke research and clinical stroke therapeutic needs. Few animal models of stroke target the large vessels that produce cortical deficits seen in the clinical setting. Also, current routes of drug administration, intraperitoneal and intravenous, do not mimic the clinical route of intra-arterial drug administration. To bridge this divide, we have retro-engineered a mouse model of stroke from the current standard of care for emergent large vessel occlusion (ELVO) stroke, endovascular thrombectomy, to include selective intra-arterial pharmacotherapy administration. Using the tandem transient common carotid and middle cerebral artery occlusion (MCAo) model to induce stroke, we threaded micro-angio tubing into the external carotid artery (ECA) towards the bifurcation of the common carotid and internal carotid arteries (CCA/ICA) allowing for the delivery of agents to the site of acute ischemia. Our model was optimized through a flow rate and injection volume study using carbon black ink injected through the intra-arterial model at different flow rates and injection volumes. The purpose of this study was to demonstrate that our injections were arriving at the site of ischemia and to improve injection volumes for future dosing while mitigating systemic side effects by preventing or minimizing systemic distribution. We determined that a flow rate of 2.5 µl/minute and injection volume of 10 µl was optimal. Next, we tested potential neuroprotective compounds nitroglycerin, verapamil, and a combination of verapamil and lubeluzole. Compounds were chosen for drug synergy and to target specific pathways in either an acute or delayed manner. Acute treatments included nitroglycerin and/or verapamil while delayed treatment included lubeluzole. The known mechanism of action for FDA approved nitroglycerin is through vessel dilation that results in increased blood flow to the treated region. A secondary mechanism of nitroglycerin is the production of nitric oxide, which has demonstrated antioxidant and anti-apoptotic effects when processed and released from cells surrounding the blood vessels. Verapamil, a calcium channel blocker, also FDA-approved for cerebral artery vasospasm: is thought to act by blocking the L-type calcium channels on the cell membrane from opening following membrane depolarization after insult. Finally, lubeluzole, also FDA-approved, is proposed to work as an NMDA modulator inhibiting the release of glutamate and nitric oxide synthase and blocking sodium and calcium channels. Through our stroke model we were able to demonstrate that each drug(s) showed a significant decrease in infarct volume and improved functional recovery while simultaneously minimizing potential systemic side effects suggesting that our stroke model may improve the preclinical validation of potential stroke therapies and help bridge the bench to bedside divide in developing new stroke therapies.

No description available.

Ischämietoleranz bezeichnet das Phänomen, dass ein kurzer ischämischer, metabolischer oder physikalischer Stimulus das Gehirn paradoxerweise "resistent" macht gegenüber einer darauffolgenden, längerdauernden Ischämie. In einer retrospektiven Studie versuchten wir die Hypothese zu untermauern, dass transiente ischämische Attacken (als kurzdauernde ischämische Stimuli) vor einem Infarkt (prodromale TIAs) protektiv sind gegen eine nachfolgende zerebrale Ischämie. Es zeigte sich dabei, dass Patienten mit prodromalen TIAs ein geringeres Defizit und einen günstigeren Verlauf zeigten und im CT seltener Infarktfrühzeichen hatten. Somit könnten transiente ischämische Attacken, vor einem Schlaganfall, analog zu der Situation am Herzen und wie in zahlreichen in vivo Modellen gezeigt, ein klinisches Korrelat zur hypoxischen Präkonditionierung darstellen. Im experimentellen Teil der vorliegenden Arbeit wird gezeigt, dass sich hypoxische Präkonditionierung in vitro in neuronalen Kulturen modellieren lässt. Eine kurzzeitige Sauerstoff-Glucose-Deprivation (OGD) 1-3 Tage vor einer längeren OGD führt zu einem signifikanten Schutz von Neuronen, bis zu 90%. Hypoxietoleranz kann auch durch andere metabolische Stimuli, wie Inhibition von Atmungskettenenzymen durch 3-NPA im gleichen Zeitrahmen simuliert werden. Eine genaue Kenntnis der endogenen Neuroprotektion durch Ischämietoleranz könnte in Zukunft helfen, den Schaden durch ischämische Infarkte und ischämische Enzephalopathien zu minimieren. / Ischemic tolerance is a phenomenon where a brief episode of ischemia renders the brain resistant against a subsequent, longerlasting ischemic event. In a retrospective study we tested the hypothesis that transient ischemic attacks (as brief ischemic stimuli) before cerebral ischemia (prodromal TIA's) may have a protective effect. Here we show that patients with prodromal TIA's have less severe neurologic impairment, a better clinical course and have less early infarct signs. Therefore we siggest that TIA's, before stroke could represent a clinical correlate to hypoxic preconditioning, as shown in the heart. Experimentally we were able to model hypoxic preconditioning in vitro using neuronal cultures. Brief oxygen-glucose deprivation (OGD) 1-3 days before longer lasting OGD protects neurons, up to 90%. Hypoxic tolerance was also simulated by metabolic stimuli like inhibition of the respiratory chain by 3-NPA. Increasing knowledge of this endogenous neuroprotection by ischemic tolerance might help to minimize neuronal damage following ischemic strokes and hypoxic encephalopathy.

A isquemia cerebral é uma enfermidade grave, de incidência e prevalência global, considerada uma das principais causas de morte e incapacidade no mundo. Ela é decorrente da hipoperfusão ou interrupção sanguínea em uma determinada região encefálica e a falta de oxigênio e glicose leva a falha no metabolismo energético de neurônios e células gliais. A morte destas células libera grande quantidade de glutamato, o principal neurotransmissor excitatório, o que desencadeia a cascata isquêmica, formada por estresse oxidativo, excitotoxicidade e processo inflamatório. Estes insultos causam danos teciduais graves que comprometem, principalmente, o sistema sensorimotor, memória, cognição e as emoções. A guanosina, um derivado da guanina, tem mostrado papel neuroprotetor ao sistema nervoso central, agindo no sistema glutamatérgico. Esses efeitos têm sido demonstrados em ratos machos, mas não em fêmeas, por isso, o objetivo desta tese foi investigar através de testes comportamentais, imunoistoquímico e histológico, a ação da guanosina em ratos Wistar machos e fêmeas induzidos cirurgicamente a um modelo de isquemia focal permanente do córtex cerebral parietal, levando em consideração o ciclo estral das fêmeas imediatamente antes da indução isquêmica. Este trabalho foi aprovado pela Comissão de Ética no Uso de Animais da UFRGS (Nº 29396). Após a verificação do ciclo estral, fêmeas e machos foram anestesiados, posicionados em aparelho estereotáxico e a isquemia focal cortical foi induzida por termocoagulação dos vasos piais. Ao término da cirurgia, os animais foram tratados com solução salina 0,9% ou guanosina 60 mg/kg, ambos por via intraperitoneal, em 4 doses (0, 1, 3 e 6 horas após a indução isquêmica). No teste do cilindro, as fêmeas apresentaram significativamente melhor recuperação sensorimotora a longo prazo comparadas aos machos. No teste do campo aberto, memória de habituação a longo prazo e locomoção em fêmeas foram prejudicadas pela isquemia e os machos não apresentaram prejuízo. No teste do labirinto em cruz elevado não houve diferença significativa entre os grupos. No teste claro/escuro, as fêmeas isquêmicas demonstraram comportamento ansiolítico comparadas aos machos e às fêmeas naïves. A imunoistoquímica de astrócitos e a mensuração do volume de lesão não apresentaram diferença estatística entre os grupos. Com este trabalho demonstrou-se a importância da realização de pesquisas em ambos os gêneros, considerando o ciclo estral, principalmente para enfermidades complexas como a isquemia cerebral. O tratamento com a guanosina é promissor, principalmente na recuperação motora em fêmeas, entretanto, estudos futuros são necessários para melhor compreendimento dos mecanismos envolvidos. / Ischemic stroke is a serious disease of global incidence and prevalence, considered a leading cause of death and disability worldwide. It is due to hypoperfusion or blood disruption in a brain region and the lack of oxygen and glucose leads to failure in energetic metabolism of neurons and glial cells. The death of these cells releases large amount of glutamate, the main excitatory neurotransmitter, which triggers the ischemic cascade, formed by oxidative stress, excitotoxicity and inflammatory processes. These insults cause severe tissue damage that mainly compromise the sensorimotor system, memory, cognition and emotions. Guanosine, a guanine derivative, has shown a neuroprotective role in the central nervous system, acting on the glutamatergic system. These effects have been demonstrated in male rats, but not in females, so the aim of this thesis was to investigate through behavioral, immunohistochemical and histological tests, the action of guanosine in male and female Wistar rats surgically induced to a model of focal permanent cerebral ischemia in the motor cortex, considering the female estrous cycle immediately before the ischemic induction. This work was approved by the UFRGS Ethical Committee on the Use of Animals (No. 29396). After estrous cycle verification, females and males were anesthetized, positioned in a stereotaxic apparatus, and cortical focal ischemia was induced by thermocoagulation of the pial vessels. At the end of the surgery, the animals were treated with 0.9% saline or guanosine 60 mg/kg, both intraperitoneally, in 4 doses (0, 1, 3 and 6 hours after ischemic induction). In the cylinder test, females presented significant long-term sensorimotor recovery compared to males. In the open field test, long-term memory habituation and locomotion/exploratory activity in females were impaired by ischemia and males showed no impairment. In the elevated plus maze test, there was no significant difference between groups. In the light/dark test, the ischemic females showed anxiolytic-like behavior compared to naïve males and females. The immunohistochemistry of astrocytes and the measurement of lesion volume did not show any statistical difference between groups. With this work it was demonstrated the importance of conducting researches in both genders, considering the estrous cycle, mainly for complex diseases such as cerebral ischemia. The treatment with guanosine is promising, especially in motor recovery in females; however, future studies are necessary to better understand the mechanisms involved.

Introdução: Existem poucos dados a respeito do diagnóstico e prognóstico de crianças com acidente vascular encefálico isquêmico (AVE-i) devido a arteriopatia/vasculopatia pós-varicela e nenhuma revisão sistemática em crianças com arteriopatia/vasculopatia transitória. Objetivos: Relatar série de casos de sete crianças com AVE-i pós-varicela focando nos aspectos clínico/laboratoriais e no desempenho neuro-cognitivo 4 anos após e realizar revisão sistemática da literatura sobre a associação entre VZV e arteriopatia/vasculopatia transitória. Métodos: Revisão sistemática-Estudos relevantes foram buscados utilizando os seguintes bancos de dados: EMBASES; Pubmed; Bireme; LILACS e Web of Science. As buscas utilizaram as seguintes palavras-chave: arteriopatia transitória / vasculopatia ou pós-varicela ou arteriopatia focal e VZV. Os descritores usados para revisão sistemática foram: Arteriopatia transitória or vasculopatia transitória or arteriopatia pós-varicela or arteriopatia focal e VZV or varicela e aplicada a estratégia de PICO; População: crianças de 1 mês a 17 anos e 11 meses, com vasculopatia/arteriopatia em sistema nervoso central; Fenômeno de Interesse: VZV até 12 meses anterior; Comparação: Vasculopatia/Arteriopatia transitória sem associação com VZV; Outcome: VZV associado a vasculopatia. Os artigos selecionados foram analisados por 2 examinadores que validaram os artigos de acordo com a escala New Castle Otawa. Um terceiro examinador resolveu discrepâncias. Série de relato de casos: envolveu 7 crianças (5 meninos e 2 meninas) de 5 serviços de emergências pediátricas na cidade de São Paulo, Brasil, que apresentaram acidente vascular encefálico isquêmico pós-varicela confirmada com ressonância magnética de encéfalo e angioressonância magnética cerebral. Foi realizado coleta de líquido cefalorraquidiano para detecção do envolvimento do VZ: dosagem de anticorpos IgG e IgM anti-VZV; reação em cadeia de polimerase para DNA viral e detecção do envolvimento do vírus herpes simples tipo 1 e tipo 2 (anticorpos IgG e IgM anti-VHS 1 e 2). Foi aplicado o PSOM-Score na admissão e 4 anos após o AVE-i. Resultados: Na revisão sistemática foram selecionados 1003 artigos sendo que no final das avaliações apenas 11 artigos com moderado nível de evidência para associação entre arteriopatia transitória e VZV foram incluídos na nossa revisão. Em relação à série de casos, os 7 pacientes, com idades variando de 1,3 anos a 4 anos, apresentaram hemiparesia ao exame físico inicial e imagem de isquemia em região submetida à irrigação da artéria cerebral média ou interna após um tempo médio de 5,1 (± 3,5) meses do quadro clínico de varicela. Em 4 pacientes (57%) foram encontradas lesões vasculares e a detecção de IgG anti VZV no liquor ocorreu em 3 pacientes (42%). Nenhum paciente apresentou exantema, febre ou presença de anticorpos anti-herpes vírus tipo 1 e 2. Somente 1 paciente apresentou alteração nos exames de trombofilia (mutação em heterozigose da protombina). Todos apresentaram melhora nos índices de escore para sequelas. Nenhum apresentou novo episódio de AVE-i. Limitacão do nosso estudo: Limitado número de casos e pequeno número de estudos caso-controle ou estudos randomizados para realização de revisão sistemática. Conclusão: Encontramos moderado nível de evidência para associação entre arteriopatia transitória e VZV na revisão sistemática. Nessa série de casos foi observado o caráter não progressivo do AVE-i pós-varicela após 4 anos de seguimento através da avaliação de sequelas motoras, de linguagem e cognitivas. Observamos que a identificação do DNA viral e/ou presença intratecal de IgG anti-VZV não foram determinantes para o diagnóstico. Dessa forma existe necessidade de se buscar melhores marcadores diagnósticos de acidente vascular isquêmico pós-varicela em crianças / Introduction: Few data exist about the diagnosis and prognosis of children who were victims of an arterial ischemic stroke (AIS) caused by post-varicella vasculopathy/artheriopathy and there is no systematic review about children with transitory artheriopathy/vasculopathy. Objetives: To report seven cases of children who suffered post-varicella AIS, with special focus to the clinical/laboratory aspects, in addition to their neuro-cognitive performance after four years. We also perform a systematic review about the association between VZV and transitory artheriopathy/vasculopathy. Methods: Systematic review. Relevant studies were sought using the following data-bases: EMBASES; Pubmed; Bireme; LILACS and Web of Science. Searches used the following keywords: transitory artheriopathy/ vasculopathy or post varicella artheriopathy or focal artheriopathy and VZV. The PICO method was used for the selection of studies. Population: 1 month to 17 years-old, with vasculopathy/ artheriopaty in central nervous system; end-point: VZV up to 12 months before; Comparation: Transitory Vasculopathy/Artheriopaty without VZV; Outcome: VZV associated with vasculopaty/artheriopaty. One examiner performed study selection. The selected articles were analyzed by two examiners who validated the articles according to Newcastle Otawa scale. A third examiner resolved discrepancies. Series of cases: seven children were evaluated (5 boys and 2 girls) from five different pediatric emergency services within the city of Sao Paulo, Brazil, all presenting with arterial ischemic stroke (AIS) caused by post-varicella vasculopathy. Diagnosis was confirmed by Magnetic Resonance Imaging and Nuclear Magnetic Resonance Angiography. Virological diagnosis was determined using cerebrospinal fluid to detect: a) the presence of VZV DNA by polymerase chain reaction and VZV IgG and IgM antibodies and b) the involvement of the Herpes Simplex Virus type 1 and 2 (HSV 1 and 2 IgG and IgM Antibodies). The PSOM-score was applied at admission and four years after the AIS. Results: A total of 1003 publications was selected and at final evaluation only 11 articles were included with a moderate evidence level. Regarding the series of cases, seven patients, ages varying from 1.3 and 4 years, presented with hemiparesis at first physical examination and ischemic zones on imaging tests in areas irrigated by the middle cerebral artery or the internal carotid artery about 5.1 (± 3,5) months after varicella infection. Four patients (57%) had vascular lesions and three patients (42%) tested positive for VZV IgG antibodies in their CSF. No patient showed signs of exanthema, fever or IgG and IgM antibodies for Herpes Simplex Virus type 1 and 2. Thrombophilia testing came back altered for only one patient (heterozygous prothrombin gene mutation). All patients showed improvement on their sequelae scores. None recurred. Limits of this study: limited number of cases and small number of case- control studies or randomized studies for systematic review. Conclusions: We found moderate evidence level of association between transitory artheriopathy and VZV. In the series of cases, we observed the non-progressive aspect of the post-varicella AIS after four years, determined by the evaluation of motor, language and cognitive sequelae. We also observed that anti-viral DNA and/or the presence of intrathecal anti- VZV IgG antibodies were not determinants for the diagnosis. Therefore, we believe better diagnostic markers for post-varicella arterial ischemic stroke are necessary

Der ischämische Schlaganfall ist global eine der bedeutendsten Volkskrankheiten. Die derzeit verfügbaren kurativen Therapieoptionen werden vorrangig durch ein enges therapeutisches Zeitfenster limitiert. Ziel der aktuellen Schlaganfallforschung ist die Entwicklung von über dieses Zeitfenster hinaus wirksamen Therapien. Ein vielversprechender neuer Ansatz ist die experimentelle Behandlung mit humanen Nabelschnurblutzellen. Diese Arbeit erforscht das therapeutische Zeitfenster für die systemische Therapie des ischämischen Schlaganfalls mittels mononukleärer Nabelschnurblutzellen (hUCB MNC) in spontanhypertensiven Ratten nach permanentem Verschluss der Arteria cerebri media (pMCAO). Hierzu wurden die Therapiezeitpunkte 4, 24, 72, 120 Stunden und 14 Tage nach experimentellem Schlaganfall in einem komplexen Studiendesign inklusive neurofunktioneller Tests, magnetresonanztomographischer und immunhistochemischer Verfahren untersucht. In vitro wurde der Einfluss kokultivierter hUCB MNC auf Nekrose und Apoptose in neuralem Gewebe unter Sauerstoff-Glukose-Deprivation betrachtet. Die Studie ergab eine verbesserte funktionelle Rekonvaleszenz und eine geringere Ausprägung von Atrophie und Astroglianarbe bei Therapie innerhalb eines 72- Stunden-Zeitfensters. In vitro wurde eine signifikante Reduktion von Nekrose und Apoptose durch kokultivierte hUCB MNC beobachtet. Eine histologische Relokalisierung der intravenös applizierten Zellen war in keiner Therapiegruppe möglich. Die Integration der hUCB MNC ins Hirnparenchym stellt somit keine conditio sine qua non für die funktionelle Erholung nach Schlaganfall dar. Trotz des beobachteten erweiterten Zeitfensters ist die Translation dieses Therapieansatzes in die klinische Realität kritisch zu diskutieren, da weiterführende Studien unserer Arbeitsgruppe eine limitierte Wirksamkeit unter sehr praxisnahen Bedingungen (z.B. Einsatz kryokonservierter hUCB MNC) gezeigt haben. / Experimental treatment strategies using human umbilical cord blood mononuclear cells (hUCB MNCs) represent a promising option for alternative stroke therapies. An important point for clinical translation of such treatment approaches is knowledge on the therapeutic time window. Although expected to be wider than for thrombolysis, the exact time window for hUCB MNC therapy is not known. Our study aimed to determine the time window of intravenous hUCB MNC administration after middle cerebral artery occlusion (MCAO). Male spontaneously hypertensive rats underwent MCAO and were randomly assigned to hUCB MNC administration at 4h, 24h, 72h, 120h or 14d. Influence of cell treatment was observed by magnetic resonance imaging on days 1, 8 and 29 following MCAO and by assessment of functional neurological recovery. On day 30, brains were screened for glial scar development and presence of hUCB MNCs. Further, influence of hUCB MNCs on necrosis and apoptosis in post-ischemic neural tissue was investigated in hippocampal slices cultures. Transplantation within a 72h time window resulted in an early improvement of functional recovery, paralleled by a reduction of brain atrophy and diminished glial scarring. Cell transplantation 120h post MCAO only induced minor functional recovery without changes in the brain atrophy rate and glial reactivity. Later transplantation (14d) did not show any benefit. No evidence for intracerebrally localized hUCB MNCs was found in any treatment group. In vitro hUCB MNCs were able to significantly reduce post-ischemic neural necrosis and apoptosis. Our results for the first time indicate a time window of therapeutic hUCB MNC application of at least 72 hours. The time window is limited, but wider than compared to conventional pharmacological approaches. The data furthermore confirms that differentiation and integration of administered cells is not a prerequisite for poststroke functional improvement and lesion size reduction.

Τα ΑΕΕ είναι η πρώτη αιτία αναπηρίας και η τρίτη αιτία θανάτου παγκοσμίως. Επίσης οι ασθενείς με ΑΕΕ είναι οι συχνότεροι χρήστες των υπηρεσιών υγείας. Παράλληλα, στη χώρα μας δαπανάται ετησίως το 10% του Ακαθάριστου Εγχώριου Προϊόντος (ΑΕΠ) για την υγεία σε σχέση με το μέσο όρο του 8,9% των χωρών του Οργανισμού Οικονομικής Συνεργασίας και Ανάπτυξης (ΟΟΣΑ). Στόχος της μελέτης είναι η οικονομική αξιολόγηση του ενδο-νοσοκομειακού κόστους ασθενών με οξύ ΑΕΕ στην Ελλάδα καθώς επίσης και ο προσδιορισμός ανεξάρτητων παραγόντων που επηρεάζουν το κόστος νοσηλείας. Καταγράφηκαν δημογραφικά και κλινικά χαρακτηριστικά σε 429 συνεχόμενους ασθενείς με οξύ ΑΕΕ (ισχαιμικό ή αιμορραγικό) που εισήχθησαν σε όλες τις κλινικές του Πανεπιστημιακού Γενικού Νοσοκομείου Πατρών για διάστημα 18 μηνών. Υπολογίσαμε το κόστος, για κάθε ασθενή ατομικά, από την ώρα της εισβολής του ΑΕΕ έως την έξοδό του από το νοσοκομείο. Το κόστος μετρήθηκε σε ευρώ (€) και σύμφωνα με τις πραγματικές δαπάνες του νοσοκομείου. Η μέση ηλικία των ασθενών ήταν 68.9 (±12.7) έτη και η διάρκεια νοσηλείας ήταν 10.9 (±7.9) ημέρες. Οι 345 ασθενείς (80%) είχαν ισχαιμικό ΑΕΕ και 84 (20%) είχαν πρωτοπαθή ενδοεγκεφαλική αιμορραγία. Το άμεσο ενδο-νοσοκομειακό κόστος νοσηλείας όλων των ασθενών με οξύ ΑΕΕ ανήλθε στα 1.551.445,00 € για μια συνολική διάρκεια νοσηλείας 4.674 ημερών (331,9 € ανά ημέρα νοσηλείας). Το μέσο ενδονοσοκομειακό κόστος ανά ασθενή με ΑΕΕ ήταν 3.624,9(±2695.4) €. Το 59% του συνολικού κόστους αποδόθηκε στο κόστος "κλίνης και προσωπικού", (6%) "προ εισαγωγής", (13%) "εργαστηριακό έλεγχο", (6%) "απεικονιστικό έλεγχο", (8%) "αποκλειστική νοσηλευτική φροντίδα", (7%) "φαρμακευτική αγωγή", (0.6%) "θεραπεία αποκατάστασης" και (0.7%) "διάφορα έξοδα". Τα αιμορραγικά ΑΕΕ είχαν σημαντικά μεγαλύτερο κόστος από τα ισχαιμικά ΑΕΕ (μέσο 5305.4 και 3.214,5 €, αντίστοιχα). Μεταξύ των υπότυπων των ισχαιμικών ΑΕΕ το συνολικό μέσο κόστος ήταν σημαντικά χαμηλότερο για τα "κενοτοπιώδη" έμφρακτα (2328.7±1100.2 €). Η διάρκεια νοσηλείας είχε υψηλή συσχέτιση με το συνολικό ενδο-νοσοκομειακό κόστος. Η πολυπαραγοντική γραμμική ανάλυση παλινδρόμησης έδειξε ότι το τμήμα εισαγωγής, η βαρύτητα του ΑΕΕ στην εισαγωγή, ο τύπος του ΑΕΕ και η κατάσταση εξόδου ήταν ανεξάρτητοι παράγοντες του κόστους. Αν επιθυμούμε τη συγκράτηση του νοσοκομειακού κόστους, θα πρέπει να ληφθούν υπόψη πολιτικές διοίκησης που στοχεύουν στη μείωση της διάρκειας νοσηλείας. / Stroke is the first cause of disability and the third cause of death worldwide. Moreover, in the western countries, the stroke patients are the most frequent users of all the health services and the hospital budgets. At the same time, 10% of the Gross Domestic Product (GDP) is annually spent on health in relation with the average 8.9% of the Organisation for Economic Co-operation and Development (OECD) countries. Aim of this study is the economic evaluation on the in-hospital cost of patients with an acute stroke in Greece and the identification of potential independent factors influencing this cost. Demographic and clinical data were recorded on 429 consecutive patients with an acute stroke (ischemic and hemorrhagic), admitted to the University General Hospital of Patras during a period of 18 months. We calculated the cost, individually for each patient, from the stroke onset until the discharge from the hospital. The cost was measured in euro (€), according to the real expenditure of hospital. Mean age was 68.9 (±12.7) years and length of stay (LOS) was 10.9 (±7.9) days. In all, 345 patients (80%) had an ischemic stroke and 84 (20%) had a primary intracerebral hemorrhage. The direct in-hospital cost of all stroke patients, 1.551.445,00 €, accounted for a total hospitalisation of 4.674 days (331.9 € per day in hospital). The mean in-hospital cost per patient was 3.624,9 (±2695.4) €. The 59% of the total cost concerns the cost of "bed and staff", (6%) "pre-hospital cost", (13%) "laboratory investigations", (6%) "imaging investigations", (8%) "supportive nursing", (7%) "medication", (0.6%) "rehabilitation therapy" and (0.7%) "other expenses". Hemorrhagic strokes were significantly more expensive than the ischemic strokes (mean 5305.4 (± 4204.8) € and 3214,5 (±1976.2) € respectively). Amongst ischemic stroke subtypes the mean total cost was significantly lower for lacunar strokes (2328.7 ± 1100.2 €). The length of stay was highly correlated with in-hospital total cost. Multivariate linear regression model showed that the admission ward, stroke severity on admission, stroke type and status discharge were independent predictors of cost. In order to withhold the hospital cost, policies of administration that aiming to the reduction of length of stay should be taken into consideration.