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1.
J Med Virol ; 96(6): e29735, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38864313

RESUMO

Recently, hepatitis E virus (HEV, Paslahepevirus balayani) particles were detected for the first time in the ejaculate of two chronically infected patients. Since then, we have been able to detect HEV in ejaculate in five further patients, and thus in a total of seven out of nine (78%) chronically infected men (age 36-67 years, median 56 years). In five patients, the HEV RNA concentration was more than 100-fold higher compared to the serum, while in two patients, the viral load was more than 10-fold lower. However, it has remained unclear whether viral particles shed in the ejaculate were infectious, as a previous cell culture model had failed to demonstrate the infectivity. In the current study, we employed an optimized HEV cell culture system based on overconfluent PLC/PRF/5 cells to investigate the infectivity of HEV particles from ejaculate and other body fluids. With this approach, we were able to show for the first time that HEV particles in the ejaculate from several patients were infectious. HEV replicated to high viral loads of 1e9 HEV RNA copies per ml. This indicates that HEV-positive ejaculate could bear a risk of infection for sexual partners.


Assuntos
Vírus da Hepatite E , Hepatite E , RNA Viral , Carga Viral , Humanos , Vírus da Hepatite E/isolamento & purificação , Pessoa de Meia-Idade , Hepatite E/virologia , Masculino , Adulto , Idoso , RNA Viral/análise , Sêmen/virologia , Vírion , Linhagem Celular , Eliminação de Partículas Virais
2.
Ann Hematol ; 2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38459156

RESUMO

Rituximab, gemcitabine and oxaliplatin (R-GemOx) has demonstrated to be effective and safe in lymphoma patients. We aimed to determine the maximum tolerated dose (MTD) of oxaliplatin in combination with rituximab and gemcitabine and to explore the efficacy and safety of R-GemOx in relapsed or refractory (r/r) indolent and mantle cell lymphoma (MCL). In this single-arm, phase I/II trial, we enrolled 55 patients with r/r indolent lymphoma and MCL not suitable for autologous stem-cell transplantation. Patients received 4 cycles of R-GemOx. In the dose escalation group, 70 mg/m2 of oxaliplatin was applied and interindividually increased by 10 mg/m2 until the MTD was reached together with fixed doses of rituximab and gemcitabine. At the oxaliplatin MTD, an extension cohort was opened. Primary aim was to detect an overall response rate (ORR) greater than 65% (α = 0.05). Oxaliplatin 70 mg/m2 (MTD) was chosen for the extension cohort after 3 of 6 patients experienced a DLT at 80 mg/m2. Among 46 patients evaluable for the efficacy analysis ORR was 72% (33/46), missing the primary aim of the study (p = 0.21). After a median follow-up of 7.9 years, median PFS and OS were 1.0 and 2.1 years. Most frequent grade ≥ 3 adverse events were cytopenias. R-GemOx induces decent response rates in r/r indolent lymphoma and MCL, though novel targeted therapies have largely replaced chemotherapy in the relapse setting. Particularly in MCL, R-GemOx might be an alternative option in late relapses or as bridging to CAR-T-cells. This study was registered with ClinicalTrials.gov on Aug 4th, 2009, number NCT00954005.

3.
Z Gastroenterol ; 62(1): 62-72, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38195110

RESUMO

Liver transplantation (LT) has emerged as a standard of care for patients with end-stage liver disease, providing a life-saving intervention for patients with severely compromised liver function in both the acute and chronic setting. While LT has also become a routine procedure for early-stage hepatocellular carcinoma (HCC), offering a potential cure by treating both the tumor and the underlying liver disease, its relevance in the context of other malignancies such as cholangiocellular carcinoma (CCA), combined hepatocellular-cholangiocarcinoma (cHCC-CCA) or liver metastases is still the subject of intense debate and no definite recommendations have yet been established. This review summarizes the current therapeutic standards in the context of LT for gastrointestinal malignancies and provides a reflection and outlook on current scientific and clinical developments.


Assuntos
Neoplasias dos Ductos Biliares , Carcinoma Hepatocelular , Colangiocarcinoma , Neoplasias Gastrointestinais , Neoplasias Hepáticas , Transplante de Fígado , Humanos , Carcinoma Hepatocelular/cirurgia , Neoplasias Hepáticas/cirurgia , Neoplasias Gastrointestinais/cirurgia , Colangiocarcinoma/cirurgia , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos
4.
Childs Nerv Syst ; 39(12): 3457-3466, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37261536

RESUMO

PURPOSE: Pineal region cysts (PCs) may affect the tectum and aqueduct and cause deep central vein congestion. Beside headaches, PC often causes a broad range of symptoms, leading to prolonged diagnosis and therapy. The aims of this study are to reveal parameters that might explain the ambiguity of the symptoms and to identify factors in association with the respiration-driven neurofluid system. METHODS: This retrospective study included 28 paediatric patients (mean age 11.6 years) who received surgical treatment and 18 patients (mean age 11.3 years) who were followed conservatively. Symptoms, time to diagnosis, cyst size, ventricular indices, head circumference and postoperative outcome, were analysed. Four patients were investigated for CSF dynamics with real-time MRI. The mean follow-up time was 1.6 years. RESULTS: The most common early onset symptoms were headaches (92%), blurred vision (42.8%), sleep disturbances (39.3%) and vertigo (32.1%). Tectum contact was observed in 82% of patients, and MRI examinations revealed that imaging flow void signals were absent in 32.1% of patients. The maximal cyst diameters were 13.7 × 15.6 mm (mean). Together with a postoperative flow void signal, 4 patients recovered their respiration-driven CSF aqueductal upward flow, which was not detectable preoperatively. After surgery the main symptoms improved. CONCLUSION: Despite proximity to the aqueduct with frequently absent flow void signals, hydrocephalus was never detected. Data from real-time MRI depicted a reduced preoperative filling of the ventricular CSF compartments, indicating a diminished fluid preload, which recovered postoperatively.


Assuntos
Neoplasias Encefálicas , Cistos do Sistema Nervoso Central , Cistos , Hidrocefalia , Glândula Pineal , Humanos , Criança , Estudos Retrospectivos , Neoplasias Encefálicas/complicações , Cistos do Sistema Nervoso Central/cirurgia , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/etiologia , Hidrocefalia/cirurgia , Cistos/complicações , Imageamento por Ressonância Magnética/métodos , Cefaleia/etiologia , Glândula Pineal/diagnóstico por imagem , Glândula Pineal/cirurgia
5.
Z Gastroenterol ; 61(11): 1472-1483, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36972596

RESUMO

BACKGROUND: Liver failure (LF) is characterised by a loss of the synthetic and metabolic liver function and is associated with a high mortality. Large-scale data on recent developments and hospital mortality of LF in Germany are missing. A systematic analysis and careful interpretation of these datasets could help to optimise outcomes of LF. METHODS: We used standardised hospital discharge data of the Federal Statistical Office to evaluate current trends, hospital mortality and factors associated with an unfavourable course of LF in Germany between 2010 and 2019. RESULTS: A total of 62,717 hospitalised LF cases were identified. Annual LF frequency decreased from 6716 (2010) to 5855 (2019) cases and was higher among males (60.51%). Hospital mortality was 38.08% and significantly declined over the observation period. Mortality significantly correlated with patients' age and was highest among individuals with (sub)acute LF (47.5%). Multivariate regression analyses revealed pulmonary (ORARDS: 2.76, ORmechanical ventilation: 6.46) and renal complications (ORacute kidney failure: 2.04, ORhepatorenal syndrome: 2.92) and sepsis (OR: 1.92) as factors for increased mortality. Liver transplantation reduced mortality in patients with (sub)acute LF. Hospital mortality significantly decreased with the annual LF case volume and ranged from 47.46% to 29.87% in low- or high-case-volume hospitals, respectively. CONCLUSIONS: Although incidence rates and hospital mortality of LF in Germany have constantly decreased, hospital mortality has remained at a very high level. We identified a number of variables associated with increased mortality that could help to improve framework conditions for the treatment of LF in the future.


Assuntos
Falência Hepática Aguda , Falência Hepática , Masculino , Humanos , Mortalidade Hospitalar , Falência Hepática/diagnóstico , Hospitais com Alto Volume de Atendimentos , Falência Hepática Aguda/diagnóstico , Pacientes
6.
Hippocampus ; 32(7): 517-528, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35621370

RESUMO

Temporal lobe epilepsy is characterized by hippocampal neuronal death in CA1 and hilus. Dentate gyrus granule cells survive but show dispersion of the compact granule cell layer. This is associated with decrease of the glycoprotein Reelin, which regulates neuron migration and dendrite outgrow. Reelin-deficient (reeler) mice show no layering, their granule cells are dispersed throughout the dentate gyrus. We studied granule cell dendritic orientation and distribution of postsynaptic spines in reeler mice and two mouse models of temporal lobe epilepsy, namely the p35 knockout mice, which show Reelin-independent neuronal migration defects, and mice with unilateral intrahippocampal kainate injection. Granule cells were Golgi-stained and analyzed, using a computerized camera lucida system. Granule cells in naive controls exhibited a vertically oriented dendritic arbor with a small bifurcation angle if positioned proximal to the hilus and a wider dendritic bifurcation angle, if positioned distally. P35 knockout- and kainate-injected mice showed a dispersed granule cell layer, granule cells showed basal dendrites with wider bifurcation angles, which lost position-specific differences. Reeler mice lacked dendritic orientation. P35 knockout- and kainate-injected mice showed increased dendritic spine density in the granule cell layer. Molecular layer dendrites showed a reduced spine density in kainate-injected mice only, whereas in p35 knockouts no reduced spine density was seen. Reeler mice showed a homogenous high spine density. We hypothesize that granule cells migrate in temporal lobe epilepsy, develop new dendrites which show a spread of the dendritic tree, create new spines in areas proximal to mossy fiber sprouting, which is present in p35 knockout- and kainate-injected mice and loose spines on distal dendrites if mossy cell death is present, as it was in kainate-injected mice only. These results are in accordance with findings in epilepsy patients.


Assuntos
Epilepsia do Lobo Temporal , Animais , Dendritos/metabolismo , Giro Denteado , Modelos Animais de Doenças , Epilepsia do Lobo Temporal/induzido quimicamente , Epilepsia do Lobo Temporal/metabolismo , Humanos , Ácido Caínico/toxicidade , Camundongos , Camundongos Mutantes Neurológicos , Neurônios/metabolismo
7.
Childs Nerv Syst ; 38(8): 1461-1467, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35532778

RESUMO

PURPOSE: In the paediatric age group, the overall degree of evidence regarding decompressive craniectomy (DC) and cranioplasty is low, whereas in adults, randomised controlled trials and prospective multicentre registries are available. To improve the evidence-based treatment of children, a consensus was reached to establish a prospective registry under the auspices of the European Society for Pediatric Neurosurgery (ESPN). METHODS: This international multicentre prospective registry is aimed at collecting information on the indication, timing, technique and outcome of DC and cranioplasty in children. The registry will enrol patients ≤ 16 years of age at the time of surgery, irrespective of the underlying medical condition. The study design comprises four obligatory entry points as a core dataset, with an unlimited number of further follow-up entry points to allow documentation until adolescence or adulthood. Study centres should commit to complete data entry and long-term follow-up. RESULTS: Data collection will be performed via a web-based portal (homepage: www.pedccr.com ) in a central anonymised database after local ethics board approval. An ESPN steering committee will monitor the project's progress, coordinate analyses of data and presentation of results at conferences and in publications on behalf of the study group. CONCLUSION: The registry aims to define predictors for optimal medical care and patient-centred treatment outcomes. The ultimate goal of the registry is to generate results that are so relevant to be directly transferred into clinical practice to enhance treatment protocols.


Assuntos
Craniectomia Descompressiva , Neurocirurgia , Procedimentos de Cirurgia Plástica , Adolescente , Adulto , Criança , Craniectomia Descompressiva/métodos , Humanos , Estudos Multicêntricos como Assunto , Complicações Pós-Operatórias/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Sistema de Registros , Estudos Retrospectivos , Crânio/cirurgia
8.
J Hepatol ; 74(6): 1455-1471, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33577920

RESUMO

The term non-alcoholic fatty liver disease (NAFLD) was originally coined to describe hepatic fat deposition as part of the metabolic syndrome. However, a variety of rare hereditary liver and metabolic diseases, intestinal diseases, endocrine disorders and drugs may underlie, mimic, or aggravate NAFLD. In contrast to primary NAFLD, therapeutic interventions are available for many secondary causes of NAFLD. Accordingly, secondary causes of fatty liver disease should be considered during the diagnostic workup of patients with fatty liver disease, and treatment of the underlying disease should be started to halt disease progression. Common genetic variants in several genes involved in lipid handling and metabolism modulate the risk of progression from steatosis to fibrosis, cirrhosis and hepatocellular carcinoma development in NAFLD, alcohol-related liver disease and viral hepatitis. Hence, we speculate that genotyping of common risk variants for liver disease progression may be equally useful to gauge the likelihood of developing advanced liver disease in patients with secondary fatty liver disease.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas/epidemiologia , Doenças do Sistema Endócrino/epidemiologia , Gastroenteropatias/epidemiologia , Doenças Genéticas Inatas/epidemiologia , Hepacivirus , Hepatite C Crônica/epidemiologia , Síndrome Metabólica/epidemiologia , Hepatopatia Gordurosa não Alcoólica/epidemiologia , Obesidade Abdominal/epidemiologia , Complicações na Gravidez/epidemiologia , Adulto , Criança , Comorbidade , Doenças do Sistema Endócrino/tratamento farmacológico , Feminino , Gastroenteropatias/dietoterapia , Gastroenteropatias/tratamento farmacológico , Doenças Genéticas Inatas/dietoterapia , Predisposição Genética para Doença/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Masculino , Síndrome Metabólica/dietoterapia , Síndrome Metabólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/genética , Obesidade Abdominal/complicações , Obesidade Abdominal/dietoterapia , Gravidez , Fatores de Risco , Adulto Jovem
9.
J Neurosci Res ; 99(11): 2804-2821, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34323313

RESUMO

With the advent of real-time MRI, the motion and passage of cerebrospinal fluid can be visualized without gating and exclusion of low-frequency waves. This imaging modality gives insights into low-volume, rapidly oscillating cardiac-driven movement as well as sustained, high-volume, slowly oscillating inspiration-driven movement. Inspiration means a spontaneous or artificial increase in the intrathoracic dimensions independent of body position. Alterations in thoracic diameter enable the thoracic and spinal epidural venous compartments to be emptied and filled, producing an upward surge of cerebrospinal fluid inside the spine during inspiration; this surge counterbalances the downward pooling of venous blood toward the heart. Real-time MRI, as a macroscale in vivo observation method, could expand our knowledge of neurofluid dynamics, including how astrocytic fluid preloading is adjusted and how brain buoyancy and turgor are maintained in different postures and zero gravity. Along with these macroscale findings, new microscale insights into aquaporin-mediated fluid transfer, its sensing by cilia, and its tuning by nitric oxide will be reviewed. By incorporating clinical knowledge spanning several disciplines, certain disorders-congenital hydrocephalus with Chiari malformation, idiopathic intracranial hypertension, and adult idiopathic hydrocephalus-are interpreted and reviewed according to current concepts, from the basics of the interrelated systems to their pathology.


Assuntos
Cílios , Hidrocefalia , Adulto , Encéfalo , Líquido Cefalorraquidiano , Humanos , Imageamento por Ressonância Magnética/métodos
10.
Biol Chem ; 402(9): 1021-1032, 2021 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-34008380

RESUMO

This review article summarizes 20 years of our research on hepatic stellate cells within the framework of two collaborative research centers CRC575 and CRC974 at the Heinrich Heine University. Over this period, stellate cells were identified for the first time as mesenchymal stem cells of the liver, and important functions of these cells in the context of liver regeneration were discovered. Furthermore, it was determined that the space of Disse - bounded by the sinusoidal endothelium and hepatocytes - functions as a stem cell niche for stellate cells. Essential elements of this niche that control the maintenance of hepatic stellate cells have been identified alongside their impairment with age. This article aims to highlight previous studies on stellate cells and critically examine and identify open questions and future research directions.


Assuntos
Células Estreladas do Fígado , Diferenciação Celular , Hepatócitos , Humanos , Fígado , Regeneração Hepática , Nicho de Células-Tronco
11.
J Neurooncol ; 153(3): 519-525, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34148163

RESUMO

OBJECTIVE: Implantation of biodegradable Carmustine wafers in patients with malignant glioma is not generally recommended when the ventricular system is opened during tumor resection. Thrombin/fibrinogenn-covered collagen fleeces showed promising results in sufficiently closing ventricular defects. The aim of this study was to evaluate the postoperative morbidity in patients with implanted Carmustine wafers either with opened or intact ventricular system. METHODS: A consecutive series of patients who underwent resection of malignant glioma with implantation of Carmustine wafers was analyzed. In case of opening of the ventricular system, the defect in the ventricle wall was sealed using a collagen sponge coated with fibrinogen and thrombin prior to the implantation of the wafers. Postoperative adverse events (AE) and Karnofsky performance status scale (KPS) at follow up were compared between both groups. RESULTS: Fifty-four patients were included. The ventricular system was opened in 33 patients and remained intact in 21 patients. Both groups were comparable in terms of age, rate of primary and recurrent glioma, preoperative KPS, rate of gross total resection and number of implanted wafers. Postoperative AEs occurred in 9/33 patients (27.3%) with opened and in 5/21 patients (23.8%) with intact ventricular system (p = 0.13). At follow-up assessments, KPS was not significantly different between both groups (p = 0.18). Opened ventricular system was not associated with a higher incidence of postoperative AEs (p = 0.98). CONCLUSION: Appropriate closure of opened ventricular system during resection of malignant glioma allows for a safe implantation of Carmustine wafers and is not associated with a higher incidence of postoperative AEs.


Assuntos
Neoplasias Encefálicas , Glioma , Antineoplásicos Alquilantes/uso terapêutico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/cirurgia , Carmustina/efeitos adversos , Implantes de Medicamento/uso terapêutico , Glioma/tratamento farmacológico , Glioma/cirurgia , Humanos , Recidiva Local de Neoplasia , Estudos Retrospectivos , Trombina/uso terapêutico
12.
Arterioscler Thromb Vasc Biol ; 40(10): 2391-2403, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32787521

RESUMO

OBJECTIVE: Reelin, a secreted glycoprotein, was originally identified in the central nervous system, where it plays an important role in brain development and maintenance. In the cardiovascular system, reelin plays a role in atherosclerosis by enhancing vascular inflammation and in arterial thrombosis by promoting platelet adhesion, activation, and thrombus formation via APP (amyloid precursor protein) and GP (glycoprotein) Ib. However, the role of reelin in hemostasis and arterial thrombosis is not fully understood to date. Approach and Results: In the present study, we analyzed the importance of reelin for cytoskeletal reorganization of platelets and thrombus formation in more detail. Platelets release reelin to amplify alphaIIb beta3 integrin outside-in signaling by promoting platelet adhesion, cytoskeletal reorganization, and clot retraction via activation of Rho GTPases RAC1 (Ras-related C3 botulinum toxin substrate) and RhoA (Ras homolog family member A). Reelin interacts with the collagen receptor GP (glycoprotein) VI with subnanomolar affinity, induces tyrosine phosphorylation in a GPVI-dependent manner, and supports platelet binding to collagen and GPVI-dependent RAC1 activation, PLC gamma 2 (1-phosphatidylinositol-4,5-bisphosphate phosphodiesterase gamma-2) phosphorylation, platelet activation, and aggregation. When GPVI was deleted from the platelet surface by antibody treatment in reelin-deficient mice, thrombus formation was completely abolished after injury of the carotid artery while being only reduced in either GPVI-depleted or reelin-deficient mice. CONCLUSIONS: Our study identified a novel signaling pathway that involves reelin-induced GPVI activation and alphaIIb beta3 integrin outside-in signaling in platelets. Loss of both, GPVI and reelin, completely prevents stable arterial thrombus formation in vivo suggesting that inhibiting reelin-platelet-interaction might represent a novel strategy to avoid arterial thrombosis in cardiovascular disease.


Assuntos
Plaquetas/enzimologia , Lesões das Artérias Carótidas/enzimologia , Moléculas de Adesão Celular Neuronais/sangue , Proteínas da Matriz Extracelular/sangue , Proteínas do Tecido Nervoso/sangue , Neuropeptídeos/sangue , Fosfolipase C gama/sangue , Complexo Glicoproteico GPIIb-IIIa de Plaquetas/metabolismo , Glicoproteínas da Membrana de Plaquetas/metabolismo , Serina Endopeptidases/sangue , Trombose/enzimologia , Proteínas rac1 de Ligação ao GTP/sangue , Proteína rhoA de Ligação ao GTP/sangue , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Coagulação Sanguínea , Lesões das Artérias Carótidas/sangue , Lesões das Artérias Carótidas/etiologia , Moléculas de Adesão Celular Neuronais/deficiência , Moléculas de Adesão Celular Neuronais/genética , Retração do Coágulo , Citoesqueleto/enzimologia , Modelos Animais de Doenças , Proteínas da Matriz Extracelular/deficiência , Proteínas da Matriz Extracelular/genética , Camundongos da Linhagem 129 , Camundongos Endogâmicos C3H , Camundongos Endogâmicos C57BL , Proteínas do Tecido Nervoso/deficiência , Proteínas do Tecido Nervoso/genética , Ativação Plaquetária , Proteína Reelina , Serina Endopeptidases/deficiência , Serina Endopeptidases/genética , Transdução de Sinais , Trombose/sangue , Trombose/etiologia
13.
Neuropediatrics ; 52(4): 233-241, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34192788

RESUMO

New experimental and clinical findings question the historic view of hydrocephalus and its 100-year-old classification. In particular, real-time magnetic resonance imaging (MRI) evaluation of cerebrospinal fluid (CSF) flow and detailed insights into brain water regulation on the molecular scale indicate the existence of at least three main mechanisms that determine the dynamics of neurofluids: (1) inspiration is a major driving force; (2) adequate filling of brain ventricles by balanced CSF upsurge is sensed by cilia; and (3) the perivascular glial network connects the ependymal surface to the pericapillary Virchow-Robin spaces. Hitherto, these aspects have not been considered a common physiologic framework, improving knowledge and therapy for severe disorders of normal-pressure and posthemorrhagic hydrocephalus, spontaneous intracranial hypotension, and spaceflight disease.


Assuntos
Hidrocefalia , Imageamento por Ressonância Magnética , Idoso de 80 Anos ou mais , Encéfalo/diagnóstico por imagem , Encéfalo/fisiologia , Ventrículos Cerebrais/diagnóstico por imagem , Ventrículos Cerebrais/fisiologia , Humanos , Hidrocefalia/diagnóstico por imagem , Hidrocefalia/etiologia , Imageamento por Ressonância Magnética/métodos
14.
Cereb Cortex ; 30(3): 1688-1707, 2020 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-31667489

RESUMO

Reelin is an extracellular matrix protein, known for its dual role in neuronal migration during brain development and in synaptic plasticity at adult stages. During the perinatal phase, Reelin expression switches from Cajal-Retzius (CR) cells, its main source before birth, to inhibitory interneurons (IN), the main source of Reelin in the adult forebrain. IN-derived Reelin has been associated with schizophrenia and temporal lobe epilepsy; however, the functional role of Reelin from INs is presently unclear. In this study, we used conditional knockout mice, which lack Reelin expression specifically in inhibitory INs, leading to a substantial reduction in total Reelin expression in the neocortex and dentate gyrus. Our results show that IN-specific Reelin knockout mice exhibit normal neuronal layering and normal behavior, including spatial reference memory. Although INs are the major source of Reelin within the adult stem cell niche, Reelin from INs does not contribute substantially to normal adult neurogenesis. While a closer look at the dentate gyrus revealed some unexpected alterations at the cellular level, including an increase in the number of Reelin expressing CR cells, overall our data suggest that Reelin derived from INs is less critical for cortex development and function than Reelin expressed by CR cells.


Assuntos
Moléculas de Adesão Celular Neuronais/metabolismo , Giro Denteado/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Interneurônios/metabolismo , Neocórtex/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Serina Endopeptidases/metabolismo , Animais , Comportamento Animal/fisiologia , Movimento Celular/fisiologia , Giro Denteado/fisiopatologia , Hipocampo/metabolismo , Interneurônios/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurogênese/fisiologia , Neurônios/metabolismo , Folhas de Planta/metabolismo , Proteína Reelina
15.
Childs Nerv Syst ; 37(11): 3497-3507, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34152450

RESUMO

OBJECTIVE: Shunt treatment for hydrocephalus in children should aim for sustainable flexibility in regard to optional, perspective pressure level adjustment during advancing physical and mental development. Gravitation-assisted shunt valves are designed to prevent hydrostatic over-drainage frequently observed in the long course of shunt-treated hydrocephalus. We prospectively studied and analyzed the implication, safety, and feasibility for an adjustable gravitational unit combined with a fixed differential-pressure (DP) valve for neonates and infants primary shunted within the first 12 months of life. METHODS: Clinical course of hydrocephalic neonates and infants who received initial VP-shunt insertion in the early post-natal phase were monitored prospectively on the basis of our digital institutional Hydrocephalus & Shunt Registry. All patients were equipped with a fixed DP valve combined with a programmable gravitational unit activated in upright body position. Patients with a minimum shunt follow-up of 24 months were considered for further statistical analysis regarding hydrocephalus etiology, surgical setting, pre- and post-operative ventricular enlargement, head circumference, valve pressure setting, implication for the adjustment option of the gravitational unit, type and number of shunt complications, and revision-free shunt and valve survival. RESULTS: Seventy-eight pediatric patients received primary VP-shunt insertion at a mean age of 10 weeks with age gestationally corrected for preterm neonates. Hydrocephalus was related to perinatal IVH (64%), CNS malformation (11%), spina bifida (9%), congenital aqueductal stenosis (9%), and idiopathic (4%) or post-infectious etiology (3%). Fifty-two patients (70%) presented with history of prematurity (gestational age 23-36 weeks). Regular follow-up carried out for a mean period of 63 months demonstrated that ventricular enlargement decreased significantly after applied treatment and excessive head growth could be counteracted effectively. At least one pressure level adjustment was performed in 31% of all patients after 12 months, in 42% after 24 months, and in 64% at the time of last clinical follow-up since initial shunt insertion. Pressure level adjustments were successful in cases of clinical or radiographic signs of under- or over-drainage for individual patients of various ages during entire clinical course. Mean pressure setting for upright position was 24.1 cm H2O at the time of initial shunt insertion and increased to 26.4 cmH2O at the time of last clinical follow-up. Revision-free shunt-survival rates after 12 and 24 months were 79% and 70% and valve-survival rates 91% and 90%, respectively. CONCLUSION: The combination of a fixed DP valve with an adjustable gravitational unit utilized as first-line shunt regimen was feasible and safe in a highly vulnerable subgroup of hydrocephalic infants. The adjustment option for the gravitational unit showed frequent and increasing implication over time and was beneficial even during the very early developmental stage of limited autonomous mobility. To our knowledge this is the first ever reported long-term investigation of an age-consistent pediatric patient collective primary shunted with an adjustable gravitational valve system.


Assuntos
Hidrocefalia , Derivação Ventriculoperitoneal , Criança , Drenagem , Gravitação , Humanos , Hidrocefalia/cirurgia , Lactente , Estudos Retrospectivos , Resultado do Tratamento
16.
Proc Natl Acad Sci U S A ; 114(21): 5533-5538, 2017 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-28484035

RESUMO

Brain development and function depend on the directed and coordinated migration of neurons from proliferative zones to their final position. The secreted glycoprotein Reelin is an important factor directing neuronal migration. Loss of Reelin function results in the severe developmental disorder lissencephaly and is associated with neurological diseases in humans. Reelin signals via the lipoprotein receptors very low density lipoprotein receptor (VLDLR) and apolipoprotein E receptor 2 (ApoER2), but the exact mechanism by which these receptors control cellular function is poorly understood. We report that loss of the signaling scaffold intersectin 1 (ITSN1) in mice leads to defective neuronal migration and ablates Reelin stimulation of hippocampal long-term potentiation (LTP). Knockout (KO) mice lacking ITSN1 suffer from dispersion of pyramidal neurons and malformation of the radial glial scaffold, akin to the hippocampal lamination defects observed in VLDLR or ApoER2 mutants. ITSN1 genetically interacts with Reelin receptors, as evidenced by the prominent neuronal migration and radial glial defects in hippocampus and cortex seen in double-KO mice lacking ITSN1 and ApoER2. These defects were similar to, albeit less severe than, those observed in Reelin-deficient or VLDLR/ ApoER2 double-KO mice. Molecularly, ITSN1 associates with the VLDLR and its downstream signaling adaptor Dab1 to facilitate Reelin signaling. Collectively, these data identify ITSN1 as a component of Reelin signaling that acts predominantly by facilitating the VLDLR-Dab1 axis to direct neuronal migration in the cortex and hippocampus and to augment synaptic plasticity.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Moléculas de Adesão Celular Neuronais/metabolismo , Proteínas da Matriz Extracelular/metabolismo , Hipocampo/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Plasticidade Neuronal , Neurônios/fisiologia , Serina Endopeptidases/metabolismo , Proteínas Adaptadoras de Transporte Vesicular/genética , Animais , Movimento Celular , Proteínas Relacionadas a Receptor de LDL/genética , Proteínas Relacionadas a Receptor de LDL/metabolismo , Camundongos Knockout , Receptores de LDL/metabolismo , Receptores de N-Metil-D-Aspartato/isolamento & purificação , Receptores de N-Metil-D-Aspartato/metabolismo , Proteína Reelina
17.
Childs Nerv Syst ; 35(5): 833-841, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30919042

RESUMO

PURPOSE: The specific pathophysiological processes in many forms of obstructive hydrocephalus (HC) are still unclear. Current concepts of cerebrospinal fluid (CSF) dynamics presume a constant downward flow from the lateral ventricles towards subarachnoid spaces, which are in contrast to neurosurgical observations and findings of MRI flow studies. The aim of our study was to analyze CSF movements in patients with obstructive HC by neuroendoscopic video recordings, X-ray studies, and MRI. METHODS: One hundred seventeen pediatric patients with obstructive HC who underwent neuroendoscopy in our center were included. Video recordings were analyzed in 85 patients. Contrast-enhanced X-rays were conducted during surgery prior to intervention in 75 patients, and flow void signals on pre-operative MRI could be evaluated in 110 patients. RESULTS: In 83.5% of the video recordings, CSF moved upwards synchronous to inspiration superimposed by cardiac pulsation. Application of contrast medium revealed a flow delay in 52% of the X-ray studies prior to neurosurgery, indicating hindered CSF circulation. The appearances and shapes of flow void signals in 88.2% of the pre-operative MRI studies suggested valve-like mechanisms and entrapment of CSF. CONCLUSIONS: Neuroendoscopic observations in patients with obstructive HC revealed upward CSF movements and the corresponding MRI signs of trapped CSF in brain cavities. These observations are in contrast to the current pathophysiological concept of obstructive HC. However, recent real-time flow MRI studies demonstrated upward movement of CSF, hence support our clinical findings. The knowledge of cranial-directed CSF flow expands our understanding of pathophysiological mechanisms in HC and is the key to effective treatment.


Assuntos
Hidrocefalia/líquido cefalorraquidiano , Hidrocefalia/diagnóstico por imagem , Monitorização Neurofisiológica Intraoperatória/métodos , Neuroendoscopia/métodos , Adolescente , Líquido Cefalorraquidiano/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Hidrocefalia/cirurgia , Lactente , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Cirurgia Vídeoassistida/métodos
18.
Childs Nerv Syst ; 35(4): 613-619, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30726526

RESUMO

INTRODUCTION: Among children with hydrocephalus, neonates with intraventricular hemorrhage (IVH) and posthemorrhagic hydrocephalus (PH) are considered a group with one of the highest complication rates of treatment. Despite continued progress in neonatal care, a standardized and reliable guideline for surgical management is missing for this challenging condition. Thus, further research is warranted to compare common methods of surgical treatment. The introduction of neuroendoscopic lavage has precipitated the establishment of an international registry aimed at elaborating key elements of a standardized surgical treatment. METHODS: The registry is designed as a multicenter, international, prospective data collection for neonates aged 41 weeks gestation, with an indication for surgical treatment for IVH with ventricular dilatation and progressive hydrocephalus. The following initial temporizing surgical interventions, each used as standard treatment at participating centers, will be compared: external ventricular drainage (EVD), ventricular access device (VAD), ventricular subgaleal shunt (VSGS), and neuroendoscopic lavage (NEL). Type of surgery, perioperative data including complications and mortality, subsequent shunt surgeries, ventricular size, and neurological outcome will be recorded at 6, 12, 36, and 60 months. RESULTS: An online, password-protected website will be used to collect the prospective data in a synchronized manner. As a prospective registry, data collection will be ongoing, with no prespecified endpoint. A prespecified analysis will take place after a total of 100 patients in the NEL group have been entered. Analyses will be performed for safety (6 months), shunt dependency (12, 24 months), and neurological outcome (60 months). CONCLUSION: The design and online platform of the TROPHY registry will enable the collection of prospective data on different surgical procedures for investigation of safety, efficacy, and neurodevelopmental outcome of neonates with IVH and hydrocephalus. The long-term goal is to provide valid data on NEL that is prospective, international, and multicenter. With the comparison of different surgical treatment modalities, we hope to develop better therapy guidelines for this complex neurosurgical condition.


Assuntos
Hemorragia Cerebral Intraventricular/complicações , Hidrocefalia/cirurgia , Doenças do Prematuro/cirurgia , Sistema de Registros , Projetos de Pesquisa , Drenagem/métodos , Feminino , Humanos , Hidrocefalia/etiologia , Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro/etiologia , Masculino , Procedimentos Neurocirúrgicos/métodos , Procedimentos Cirúrgicos Vasculares/métodos
19.
J Hepatol ; 69(3): 594-602, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29705238

RESUMO

BACKGROUND & AIMS: To affect immune response and inflammation, the hepatitis C virus (HCV) substantially influences intercellular communication pathways that are decisive for immune cell recruitment. The present study investigates mechanisms by which HCV modulates chemokine-mediated intercellular communication from infected cells. METHODS: Chemokine expression was studied in HCVcc-infected cell lines or cell lines harbouring a subgenomic replicon, as well as in serum samples from patients. Expression or activity of mediators and signalling intermediates was manipulated using knockdown approaches or specific inhibitors. RESULTS: HCV enhances expression of CXCR2 ligands in its host cell via the induction of epidermal growth factor (EGF) production. Knockdown of EGF or of the p65 subunit of the NF-κB complex results in a substantial downregulation of HCV-induced CXCR2 ligand expression, supporting the involvement of an EGF-dependent mechanism as well as activation of NF-κB. Furthermore, HCV upregulates expression of CXCR2 ligands in response to EGF stimulation via downregulation of the T-cell protein tyrosine phosphatase (TC-PTP [PTPN2]), activation of NF-κB, and enhancement of EGF-inducible signal transduction via MEK1 (MAP2K1). This results in the production of a cytokine/chemokine pattern by the HCV-infected cell that can recruit neutrophils but not monocytes. CONCLUSIONS: These data reveal a novel EGF-dependent mechanism by which HCV influences chemokine-mediated intercellular communication. We propose that this mechanism contributes to modulation of the HCV-induced inflammation and the antiviral immune response. LAY SUMMARY: In most cases hepatitis C virus (HCV) results in chronic infection and persistent viral replication, taking decades until development of overt disease. To achieve such a course, the respective virus must have developed mechanisms to circumvent antiviral response, to modulate the inflammatory response and to utilise the infrastructure of its host with moderate effect on its viability. The present study provides novel data indicating that HCV induces epidermal growth factor production in its host cell, enhancing epidermal growth factor-inducible expression of chemokines that bind to the CXCR2 receptor and recruit neutrophile granulocytes. Importantly, chemokines are critical mediators determining the pattern of immune cells recruited to the site of injury and thereby the local inflammatory and immunological milieu. These data strongly suggest that HCV triggers mechanisms that enable the virus to influence the inflammatory and immunological processes of its host.


Assuntos
Comunicação Celular/imunologia , Fator de Crescimento Epidérmico , Hepacivirus/fisiologia , Hepatite C Crônica , Inflamação , Receptores de Interleucina-8B/imunologia , Transdução de Sinais/imunologia , Linhagem Celular , Fator de Crescimento Epidérmico/imunologia , Fator de Crescimento Epidérmico/metabolismo , Hepatite C Crônica/imunologia , Hepatite C Crônica/virologia , Interações entre Hospedeiro e Microrganismos/imunologia , Humanos , Imunidade Celular , Inflamação/imunologia , Inflamação/virologia , Regulação para Cima , Replicação Viral/fisiologia
20.
Childs Nerv Syst ; 34(3): 457-464, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-29124391

RESUMO

OBJECTIVE: Treatment monitoring and outcome evaluation in pediatric hydrocephalus require gapless documentation regarding surgical and clinical follow-up data beginning from day 1 of treatment in order to apply high quality of care. Endoscopic procedures, shunt insertion and revision surgeries, and individual modifications of valve hardware or pressure settings during follow-up as well as established outcome measurements are highly relevant for complete illustration of the patient's hydrocephalus histories. A digital tool to capture, organize, and analyze comprehensive treatment-related data was estimated long overdue, consequentially developed, and implemented in daily pediatric neurosurgical routine. METHODS: We established a self-contained, network-capable database application to supply and back up clinical information of complete surgical treatment history with implant status and follow up for all institutional pediatric hydrocephalus patients from 1995 to date. The application content has been prospectively complemented since 2012 during daily pediatric neurosurgical routine. Beside surgical data, neurological outcome and quality of life assessment were integrated according to validated scales to be recordable 2, 3, and 5 years after initial surgical intervention for prospective administration. The application is in continuous and problem-free use since implementation offering homogeneous and structured real-time information of surgical and corresponding neurological hydrocephalus-related data. By using an automatized data extraction tool, an exemplary surgical outcome evaluation reviewing institutional ventriculo-peritoneal shunt (VPS) treatment in infants over a period of more than 20 years was performed. To validate applicability, the Registry was successfully implemented in an external institution under identical conditions continuously serving for the same purpose until today. RESULTS: Upon completion of the developing process, the application was successfully implemented into routine clinical workflow of our institution. In total, 579 pediatric hydrocephalus patients entered into the Registry with collectively 1874 corresponding hydrocephalus-related surgeries (9% neuro-endoscopic procedures, 18% temporary CSF-diversions, 73% shunt surgeries) so far. For exemplary surgical outcome analysis, the total volume of complex data sets could easily be reduced stepwise in regard to requested inclusion criteria. The selection process generated conclusive data of 256 institutional pediatric VPS patients providing a median follow-up of 8.5 years. Surgical outcome was evaluated in regard to hydrocephalus etiology, applied valve design, valve augmentation, cause of initial malfunction, time to initial shunt revision, and number of total revisions. CONCLUSION: The pediatric hydrocephalus registry application delivers easy access to contemporary and up-to-date clinical information during daily clinical routine and proves comprehensive value for various scientific purposes. Institutional hydrocephalus etiologies, treatment modalities, and surgical outcome could be reviewed for a selected pediatric patient collective during an interval of more than 20 years and confirmed initial shunt treatment within the first year of age, communicating hydrocephalus and a history of prematurity as significant variables for unfavorable shunt survival and long-term revision rate. At our institution, the Registry emerged to an essential and sustainable tool to capture, organize, and analyze patterns of care in pediatric hydrocephalus patients of all etiologies and treatment modalities. Because of its adaptable and reliable predicate, a prospective multi-center utilization is currently in preparation.


Assuntos
Sistemas Computacionais/tendências , Bases de Dados Factuais/tendências , Hidrocefalia/cirurgia , Sistema de Registros , Derivação Ventriculoperitoneal/tendências , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Hidrocefalia/diagnóstico , Lactente , Masculino , Estudos Prospectivos , Estudos Retrospectivos , Resultado do Tratamento , Derivação Ventriculoperitoneal/métodos
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