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1.
Biomed Eng Online ; 23(1): 43, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38654246

RESUMO

We developed a video-based tool to quantitatively assess the Glabellar Tap Reflex (GTR) in patients with idiopathic Parkinson's disease (iPD) as well as healthy age-matched participants. We also video-graphically assessed the effect of dopaminergic medication on the GTR in iPD patients, as well as the frequency and blinking duration of reflex and non-reflex blinks. The Glabellar Tap Reflex is a clinical sign seen in patients e.g. suffering from iPD. Reliable tools to quantify this sign are lacking. METHODS: We recorded the GTR in 11 iPD patients and 12 healthy controls (HC) with a consumer-grade camera at a framerate of at least 180 images/s. In these videos, reflex and non-reflex blinks were analyzed for blink count and blinking duration in an automated fashion. RESULTS: With our setup, the GTR can be extracted from high-framerate cameras using landmarks of the MediaPipe face algorithm. iPD patients did not habituate to the GTR; dopaminergic medication did not alter that response. iPD patients' non-reflex blinks were higher in frequency and higher in blinking duration (width at half prominence); dopaminergic medication decreased the median frequency (Before medication-HC: p < 0.001, After medication-HC: p = 0.0026) and decreased the median blinking duration (Before medication-HC: p = 0.8594, After medication-HC: p = 0.6943)-both in the direction of HC. CONCLUSION: We developed a quantitative, video-based tool to assess the GTR and other blinking-specific parameters in HC and iPD patients. Further studies could compare the video data to electromyogram (EMG) data for accuracy and comparability, as well as evaluate the specificity of the GTR in patients with other neurodegenerative disorders, in whom the GTR can also be present. SIGNIFICANCE: The video-based detection of the blinking parameters allows for unobtrusive measurement in patients, a safer and more comfortable option.


Assuntos
Piscadela , Doença de Parkinson , Gravação em Vídeo , Humanos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Masculino , Feminino , Idoso , Pessoa de Meia-Idade , Processamento de Imagem Assistida por Computador/métodos , Estudos de Casos e Controles
2.
Sensors (Basel) ; 22(20)2022 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-36298342

RESUMO

Tremor is one of the common symptoms of Parkinson's disease (PD). Thanks to the recent evolution of digital technologies, monitoring of PD patients' hand movements employing contactless methods gained momentum. Objective: We aimed to quantitatively assess hand movements in patients suffering from PD using the artificial intelligence (AI)-based hand-tracking technologies of MediaPipe. Method: High-frame-rate videos and accelerometer data were recorded from 11 PD patients, two of whom showed classical Parkinsonian-type tremor. In the OFF-state and 30 Minutes after taking their standard oral medication (ON-state), video recordings were obtained. First, we investigated the frequency and amplitude relationship between the video and accelerometer data. Then, we focused on quantifying the effect of taking standard oral treatments. Results: The data extracted from the video correlated well with the accelerometer-based measurement system. Our video-based approach identified the tremor frequency with a small error rate (mean absolute error 0.229 (±0.174) Hz) and an amplitude with a high correlation. The frequency and amplitude of the hand movement before and after medication in PD patients undergoing medication differ. PD Patients experienced a decrease in the mean value for frequency from 2.012 (±1.385) Hz to 1.526 (±1.007) Hz and in the mean value for amplitude from 8.167 (±15.687) a.u. to 4.033 (±5.671) a.u. Conclusions: Our work achieved an automatic estimation of the movement frequency, including the tremor frequency with a low error rate, and to the best of our knowledge, this is the first paper that presents automated tremor analysis before/after medication in PD, in particular using high-frame-rate video data.


Assuntos
Doença de Parkinson , Tremor , Humanos , Tremor/tratamento farmacológico , Tremor/diagnóstico , Doença de Parkinson/tratamento farmacológico , Inteligência Artificial , Movimento , Mãos
3.
Biomolecules ; 12(3)2022 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-35327661

RESUMO

Parkinson's disease (PD) is associated with motor and non-motor symptoms and characterized by aggregates of alpha-synuclein (αSyn). Naturally occurring antibodies (nAbs) are part of the innate immune system, produced without prior contact to their specific antigen, and polyreactive. The abundance of nAbs against αSyn is altered in patients with PD. In this work, we biophysically characterized nAbs against αSyn (nAbs-αSyn) and determined their biological effects. nAbs-αSyn were isolated from commercial intravenous immunoglobulins using column affinity purification. Biophysical properties were characterized using a battery of established in vitro assays. Biological effects were characterized in HEK293T cells transiently transfected with fluorescently tagged αSyn. Specific binding of nAbs-αSyn to monomeric αSyn was demonstrated by Dot blot, ELISA, and Surface Plasmon Resonance. nAbs-αSyn did not affect viability of HEK293T cells as reported by Cell Titer Blue and LDH Assays. nAbs-αSyn inhibited fibrillation of αSyn reported by the Thioflavin T aggregation assay. Altered fibril formation was confirmed with atomic force microscopy. In cells transfected with EGFP-tagged αSyn we observed reduced formation of aggresomes, perinuclear accumulations of αSyn aggregates. The results demonstrate that serum of healthy individuals contains nAbs that specifically bind αSyn and inhibit aggregation of αSyn in vitro. The addition of nAbs-αSyn to cultured cells affects intracellular αSyn aggregates. These findings help understanding the role of the innate immune systems for the pathogenesis of PD and suggest that systemic αSyn binding agents could potentially affect neuronal αSyn pathology.


Assuntos
Doença de Parkinson , alfa-Sinucleína , Ensaio de Imunoadsorção Enzimática/métodos , Células HEK293 , Humanos , Neurônios/metabolismo , Doença de Parkinson/metabolismo , alfa-Sinucleína/metabolismo
4.
Front Physiol ; 12: 730995, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650443

RESUMO

While physical performance decline rates accelerate after around the age of 70 years, longitudinal athletic performance trends in athletes older than 95 years are unknown. We hypothesized a further accelerated decline in human performance in athletes who still perform at the age of 100 years. To investigate this, longitudinal data of all athletes with results at or over the age of 100 years were collected from the "World Master Rankings" data base spanning 2006-2019 (138 results from 42 athletes; 5 women, 37 men; maximum 105 years) and compared to previously published longitudinal data from 80- to 96-year-old athletes from Sweden (1,134 results from 374 athletes). Regression statistics were used to compare performance decline rates between disciplines and age groups. On average, the individual decline rate of the centenarian group was 2.53 times as steep (100 m: 8.22x; long jump: 0.82x; shot put: 1.61x; discus throw: 1.04x; javelin throw: 0.98x) as that seen in non-centenarians. The steepest increase in decline was found in the 100-m sprint (t-test: p < 0.05, no sign. difference in the other disciplines). The pooled regression statistics of the centenarians are: 100 m: R = 0.57, p = 0.004; long jump: R = 0.90, p < 0.001; shot put: R = 0.65, p < 0.001; discus throw: R = 0.73, p < 0.001; javelin throw: R = 0.68, p < 0.001. This first longitudinal dataset of performance decline rates of athletes who still compete at 100 years and older in five athletics disciplines shows that there is no performance plateau after the age of 90, but rather a further acceleration of the performance decline.

5.
Geroscience ; 43(5): 2547-2559, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34241807

RESUMO

Factors that determine individual age-related decline rates in physical performance are poorly understood and prediction poses a challenge. Linear and quadratic regression models are usually applied, but often show high prediction errors for individual athletes. Machine learning approaches may deliver more accurate predictions and help to identify factors that determine performance decline rates. We hypothesized that it is possible to predict the performance development of a master athlete from a single measurement, that prediction by a machine learning approach is superior to prediction by the average decline curve or an individually shifted decline curve, and that athletes with a higher starting performance show a slower performance decline than those with a lower performance. The machine learning approach was implemented using a multilayer neuronal network. Results showed that performance prediction from a single measurement is possible and that the prediction by a machine learning approach was superior to the other models. The estimated performance decline rate was highest in athletes with a high starting performance and a low starting age, as well as in those with a low starting performance and high starting age, while the lowest decline rate was found for athletes with a high starting performance and a high starting age. Machine learning was superior and predicted trajectories with significantly lower prediction errors compared to conventional approaches. New insights into factors determining decline trajectories were identified by visualization of the model outputs. Machine learning models may be useful in revealing unknown factors that determine the age-related performance decline.


Assuntos
Desempenho Atlético , Aprendizado de Máquina , Humanos
6.
J Parkinsons Dis ; 11(2): 833-842, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33682733

RESUMO

BACKGROUND: Parkinson's disease (PD) is the most frequent movement disorder. Patients access YouTube, one of the largest video databases in the world, to retrieve health-related information increasingly often. OBJECTIVE: We aimed to identify high-quality publishers, so-called "channels" that can be recommended to patients. We hypothesized that the number of views and the number of uploaded videos were indicators for the quality of the information given by a video on PD. METHODS: YouTube was searched for 8 combinations of search terms that included "Parkinson" in German. For each term, the first 100 search results were analyzed for source, date of upload, number of views, numbers of likes and dislikes, and comments. The view ratio (views / day) and the likes ratio (likes * 100 / [likes + dislikes]) were determined to calculate the video popularity index (VPI). The global quality score (GQS) and title - content consistency index (TCCI) were assessed in a subset of videos. RESULTS: Of 800 search results, 251 videos met the inclusion criteria. The number of views or the publisher category were not indicative of higher quality video content. The number of videos uploaded by a channel was the best indicator for the quality of video content. CONCLUSION: The quality of YouTube videos relevant for PD patients is increased in channels with a high number of videos on the topic. We identified three German channels that can be recommended to PD patients who prefer video over written content.


Assuntos
Doença de Parkinson , Mídias Sociais , Humanos , Disseminação de Informação , Gravação em Vídeo
7.
J Gerontol A Biol Sci Med Sci ; 76(8): 1376-1381, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-33606016

RESUMO

In master athletics research, cross-sectional data are easier to obtain than longitudinal data. While cross-sectional data give the age-related performance decline for a population, longitudinal data show individual trajectories. It is not known whether athletes who repeatedly compete have (a) a better performance and (b) a slower age-related decline in performance than that obtained from cross-sectional data from athletes competing only once. To investigate this, we analyzed 33 254 results of 14 118 male athletes from 8 disciplines in the database of "Swedish Veteran Athletics." For each discipline and for the pooled data of all disciplines, quadratic models of the evolution of performance over time were analyzed by ANCOVA/ANOCOVA using MATLAB. The performance was higher in athletes with 2 or more data points compared to those with only n = 1 (p < .001), with further increases in performance with an increasing number of data points per athlete. The estimated performance decline was lower in people with 2 or more results (sprint, 10 km, jumps; p < .001). In conclusion, we showed that longitudinal data are associated with higher performance and lower performance decline rates.


Assuntos
Envelhecimento/fisiologia , Desempenho Atlético , Desempenho Físico Funcional , Atletismo/fisiologia , Atletas/estatística & dados numéricos , Desempenho Atlético/fisiologia , Desempenho Atlético/estatística & dados numéricos , Big Data , Estudos Transversais , Humanos , Longevidade/fisiologia , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Modelagem Computacional Específica para o Paciente , Suécia/epidemiologia
8.
BMC Pediatr ; 20(1): 399, 2020 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-32838761

RESUMO

BACKGROUND: The diagnostic gold standard of Hirschsprung's disease (HD) is based on the histopathological assessment of colorectal biopsies. Although data on cholinergic innervation and ganglion cell (GC) distribution exist, only few studies have examined these two key features together. We assessed the pattern of cholinergic innervation and the amount of GCs in colorectal specimens of 14 HD patients. METHODS: We established a semi-quantitative score for cholinergic innervation using acetylcholinesterase (AChE) enzyme histochemistry and quantitatively analyzed the number of GCs via NADH tetrazolium reductase (NADH) enzyme histochemistry. We examined both the entire length of the resected specimens as well as defined areas of the transition zone of both pathological and healthy appearing segment. RESULTS: High AChE score values were associated with absence of GCs, and AChE scores were inversely correlated with the number of GCs. Nevertheless, we observed several cases in which one of the two features revealed a normal distribution pattern, whereas the other still displayed pathological features. CONCLUSIONS: Our data support the need for transmural colon biopsies, to enable the best evaluation of both cholinergic innervation and GCs for a reliable assessment of HD.


Assuntos
Doença de Hirschsprung , Biópsia , Colinérgicos , Doença de Hirschsprung/diagnóstico , Histocitoquímica , Humanos , Intestinos , Reto
9.
Acta Neuropathol ; 140(2): 183-208, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32529267

RESUMO

Bacterial meningitis is a deadly disease most commonly caused by Streptococcus pneumoniae, leading to severe neurological sequelae including cerebral edema, seizures, stroke, and mortality when untreated. Meningitis is initiated by the transfer of S. pneumoniae from blood to the brain across the blood-cerebrospinal fluid barrier or the blood-brain barrier (BBB). The underlying mechanisms are still poorly understood. Current treatment strategies include adjuvant dexamethasone for inflammation and cerebral edema, followed by antibiotics. The success of dexamethasone is however inconclusive, necessitating new therapies for controlling edema, the primary reason for neurological complications. Since we have previously shown a general activation of hypoxia inducible factor (HIF-1α) in bacterial infections, we hypothesized that HIF-1α, via induction of vascular endothelial growth factor (VEGF) is involved in transmigration of pathogens across the BBB. In human, murine meningitis brain samples, HIF-1α activation was observed by immunohistochemistry. S. pneumoniae infection in brain endothelial cells (EC) resulted in in vitro upregulation of HIF-1α/VEGF (Western blotting/qRT-PCR) associated with increased paracellular permeability (fluorometry, impedance measurements). This was supported by bacterial localization at cell-cell junctions in vitro and in vivo in brain ECs from mouse and humans (confocal, super-resolution, electron microscopy, live-cell imaging). Hematogenously infected mice showed increased permeability, S. pneumoniae deposition in the brain, along with upregulation of genes in the HIF-1α/VEGF pathway (RNA sequencing of brain microvessels). Inhibition of HIF-1α with echinomycin, siRNA in bEnd5 cells or using primary brain ECs from HIF-1α knock-out mice revealed reduced endothelial permeability and transmigration of S. pneumoniae. Therapeutic rescue using the HIF-1α inhibitor echinomycin resulted in increased survival and improvement of BBB function in S. pneumoniae-infected mice. We thus demonstrate paracellular migration of bacteria across BBB and a critical role for HIF-1α/VEGF therein and hence propose targeting this pathway to prevent BBB dysfunction and ensuing brain damage in infections.


Assuntos
Barreira Hematoencefálica , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Meningite Pneumocócica , Streptococcus pneumoniae , Migração Transendotelial e Transepitelial/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Barreira Hematoencefálica/metabolismo , Feminino , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Pessoa de Meia-Idade , Fator A de Crescimento do Endotélio Vascular/metabolismo
10.
Pathol Res Pract ; 216(1): 152728, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31784096

RESUMO

AIM: MGMT promoter methylation status is an important biomarker predicting survival and response to chemotherapy in patients suffering from glioblastoma. Since new diagnostic methods such as methylome-based classification of brain tumors are more and more frequently performed, we aimed at comparing the suitability of calculating the MGMT promoter methylation status in a quantitative manner from the methylome profiling as compared to the classic gold standard assessment by PCR. METHODS: Our cohort consisted of 39 cases diagnosed as "glioblastoma, IDH-wildtype" of which the MGMT promoter methylation status was analyzed with both methylation-specific PCR and high density DNA methylation array using the STP-27 algorithm. Contradictory results were validated by pyrosequencing. RESULTS: The inter-method reliability reached 77% (kappa-coefficient: 0.58) when also cases with an inconclusive result in one or the other method were taken into account. When only cases with conclusive results in both methods were considered, a very high inter-method reliability of 91% (kappa-coefficient: 0.86) could be achieved. For "methylated" cases, no contradictory results were obtained. For the remaining two cases with discrepant results subsequent pyrosequencing analyses spoke in favor of each previously applied method once. CONCLUSION: In addition to its benefits for molecular subgrouping and copy number analysis of brain tumors, DNA-methylation based classification is a highly reliable tool for the assessment of MGMT promoter methylation status in glioblastoma patients.


Assuntos
Neoplasias Encefálicas/genética , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Metilação de DNA/genética , Feminino , Glioblastoma/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Proteínas Supressoras de Tumor/metabolismo
11.
Neurosurgery ; 84(1): 190-197, 2019 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-29617848

RESUMO

BACKGROUND: Previous studies addressing the influence of surgery on the outcome of patients with glioblastomas (GBM) have not addressed molecular markers. The value of surgery versus the tumor's major biological markers remains unclear. OBJECTIVE: We investigate the extent of resection as a prognosticator for patients with newly diagnosed primary GBM with the incorporation of molecular diagnostics as per the updated WHO 2016 diagnostic criteria for GBM. METHODS: Patients with newly diagnosed GBM who underwent resection were prospectively included within a database. We analyzed patients with newly diagnosed GBM and excluded patients who presented with IDH1 R132H mutations. Gross total resection (GTR) was defined as complete removal of enhancing disease. RESULTS: One hundred seventy-five patients were included within the analysis. One hundred four patients (59.4%) had GTR, 71 patients (40.6%) had subtotal or partial resection. Eighty patients (45.7%) displayed O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation, 95 patients (54.3%) showed no MGMT promoter methylation. In Cox regression analysis, MGMT promoter methylation (hazard ratio [HR] 1.55; 95% confidence interval [CI], 1.01-2.19; P = .0133) and GTR (HR 1.48; 95% CI, 1.06-2.07; P = .0206) were significantly associated with favorable progression-free survival. MGMT promoter methylation (HR 2.13; 95% CI, 1.45-3.12; P = .0001) and GTR (HR 1.81; 95% CI, 1.24-2.63; P = .002) were associated with favorable overall survival (OS). Of other risk factors analyzed, age (>60 vs ≤ 60 yr) was significantly associated with progression-free survival (HR 1.60; 95% CI, 1.14-2.24; P = .006) and OS (HR 2.19; 95% CI, 1.51-3.19; P < .0001). CONCLUSION: GTR and MGMT promoter methylation are independent prognosticators for improved overall and progression-free survival in a homogeneous cohort of newly diagnosed patients with IDH wild-type glioblastoma.


Assuntos
Neoplasias Encefálicas/genética , Neoplasias Encefálicas/cirurgia , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Glioblastoma/genética , Glioblastoma/cirurgia , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Biomarcadores Tumorais/genética , Neoplasias Encefálicas/metabolismo , Estudos de Coortes , Metilação de DNA , Feminino , Glioblastoma/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Regiões Promotoras Genéticas , Modelos de Riscos Proporcionais
12.
Nature ; 555(7697): 469-474, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29539639

RESUMO

Accurate pathological diagnosis is crucial for optimal management of patients with cancer. For the approximately 100 known tumour types of the central nervous system, standardization of the diagnostic process has been shown to be particularly challenging-with substantial inter-observer variability in the histopathological diagnosis of many tumour types. Here we present a comprehensive approach for the DNA methylation-based classification of central nervous system tumours across all entities and age groups, and demonstrate its application in a routine diagnostic setting. We show that the availability of this method may have a substantial impact on diagnostic precision compared to standard methods, resulting in a change of diagnosis in up to 12% of prospective cases. For broader accessibility, we have designed a free online classifier tool, the use of which does not require any additional onsite data processing. Our results provide a blueprint for the generation of machine-learning-based tumour classifiers across other cancer entities, with the potential to fundamentally transform tumour pathology.


Assuntos
Neoplasias do Sistema Nervoso Central/diagnóstico , Neoplasias do Sistema Nervoso Central/genética , Metilação de DNA , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias do Sistema Nervoso Central/classificação , Neoplasias do Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Aprendizado de Máquina não Supervisionado , Adulto Jovem
13.
BMC Neurol ; 17(1): 212, 2017 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-29216848

RESUMO

BACKGROUND: Anterior sacral meningoceles are rare, and usually occur with other malformations of the posterior lower spine. While these are more frequently reported in pediatric cohorts, we report a case in an elderly woman. CASE PRESENTATION: We report on a 71 year-old woman with a recently diagnosed colorectal adenocarcinoma who presented with a severe bacterial meningitis. The cerebrospinal fluid cell count revealed a pleocytosis of 80,000 cells/µl and a severe disturbance of the blood-brain-barrier. Fusobacterium nucleatum was cultured as the causing pathogen. A lumbar MRI showed, in addition to contrast-enhancing meninges as sign of inflammation, a presacral mass. In the next step, the mass was diagnosed as an anterior sacral meningocele connected to the gut. An adequate antibiotic was used to treat the leptomeningitis. The connection between gut and meningocele was closed surgically and the patient recovered well and underwent further treatment of her colorectal adenocarcinoma. CONCLUSION: We report on a case of meningitis with an anterior sacral meningocele that was connected to the gut in a patient with a infiltrative colorectal adenocarcinoma. Anatomic variants have to be considered as rare causes of meningitis with typical intestinal germs.


Assuntos
Adenocarcinoma , Neoplasias Colorretais , Infecções por Fusobacterium/diagnóstico , Fusobacterium/patogenicidade , Região Lombossacral/patologia , Meningites Bacterianas/diagnóstico , Meningocele/diagnóstico , Idoso , Feminino , Humanos , Região Lombossacral/diagnóstico por imagem , Imageamento por Ressonância Magnética
14.
J Neurochem ; 143(5): 467-488, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28869766

RESUMO

Vaccination therapies constitute potential treatment options in neurodegenerative disorders such as Alzheimer disease or Parkinson disease. While a lot of research has been performed on vaccination against extracellular amyloid ß, the focus recently shifted toward vaccination against the intracellular proteins tau and α-synuclein, with promising results in terms of protein accumulation reduction. In this review, we briefly summarize lessons to be learned from clinical vaccination trials in Alzheimer disease that target amyloid ß. We then focus on tau and α-synuclein. For both proteins, we provide important data on protein immunogenicity, and put them into context with data available from both animals and human vaccination trials targeted at tau and α-synuclein. Together, we give a comprehensive overview about current clinical data, and discuss associated problems.


Assuntos
Doença de Alzheimer/imunologia , Peptídeos beta-Amiloides/imunologia , Doença de Parkinson/imunologia , Tauopatias/imunologia , Vacinação , Doença de Alzheimer/prevenção & controle , Peptídeos beta-Amiloides/metabolismo , Animais , Humanos , Doença de Parkinson/prevenção & controle , Tauopatias/metabolismo , Vacinação/métodos , alfa-Sinucleína/metabolismo
15.
J Exp Med ; 214(2): 423-437, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28082356

RESUMO

Inhibition of the IκB kinase complex (IKK) has been implicated in the therapy of several chronic inflammatory diseases including inflammatory bowel diseases. In this study, using mice with an inactivatable IKKα kinase (IkkαAA/AA), we show that loss of IKKα function markedly impairs epithelial regeneration in a model of acute colitis. Mechanistically, this is caused by compromised secretion of cytoprotective IL-18 from IKKα-mutant intestinal epithelial cells because of elevated caspase 12 activation during an enhanced unfolded protein response (UPR). Induction of the UPR is linked to decreased ATG16L1 stabilization in IkkαAA/AA mice. We demonstrate that both TNF-R and nucleotide-binding oligomerization domain stimulation promote ATG16L1 stabilization via IKKα-dependent phosphorylation of ATG16L1 at Ser278. Thus, we propose IKKα as a central mediator sensing both cytokine and microbial stimulation to suppress endoplasmic reticulum stress, thereby assuring antiinflammatory function during acute intestinal inflammation.


Assuntos
Proteínas de Transporte/metabolismo , Quinase I-kappa B/fisiologia , Inflamação/metabolismo , Animais , Proteínas Relacionadas à Autofagia , Proteínas de Transporte/química , Caspase 12/fisiologia , Colite/prevenção & controle , Estresse do Retículo Endoplasmático , Endorribonucleases/fisiologia , Interleucina-18/metabolismo , Camundongos , NF-kappa B/fisiologia , Proteína Adaptadora de Sinalização NOD2/fisiologia , Proteínas Serina-Treonina Quinases/fisiologia , Estabilidade Proteica , Resposta a Proteínas não Dobradas
16.
Neuromuscul Disord ; 26(4-5): 283-91, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27020463

RESUMO

Deposits of the terminal-membrane-attack-complex (MAC) C5b-9 on perfascicular endomysial capillaries are generally regarded as diagnostic hallmark of dermatomyositis (DM). Although the pathophysiology is not clear, C5b-9 deposits on capillaries seem to be associated with microinfarctions and vascular damage. Here, we report on a series of 19 patients presenting with C5b-9 accumulation on endomysial capillaries in the absence of features for DM. To decipher differences in the capillary C5b-9 accumulation pattern between DM and non-DM cases, we assessed the extent of endomysial capillary C5b-9 deposits related to capillary density and extent of myofiber necrosis by immunohistochemistry in 12 DM and 8 control patients. We found similar numbers of C5b-9-positive myofibers in both DM and non-DM C5b-9(+) cases. The distribution pattern differed as DM cases showed significantly more perifascicular capillary C5b-9 deposits as compared to non-DM cases, which presented stronger endomysial capillary C5b-9 deposits in a diffuse pattern. While total capillary density was not differing, DM patients displayed significantly more C5b-9(+) necrotic fibers as compared to non-DM C5b-9(+). In summary, endomysial capillary C5b-9 deposits are present in a variety of non-DM cases, however with differing distribution pattern. In conclusion, capillary C5b-9(+) deposits should be assessed critically, taking into consideration the distribution pattern.


Assuntos
Capilares/metabolismo , Capilares/patologia , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Músculo Esquelético/irrigação sanguínea , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia , Dermatomiosite/diagnóstico , Dermatomiosite/metabolismo , Dermatomiosite/patologia , Dermatomiosite/cirurgia , Diagnóstico Diferencial , Feminino , Seguimentos , Humanos , Doenças do Sistema Imunitário/diagnóstico , Doenças do Sistema Imunitário/metabolismo , Doenças do Sistema Imunitário/patologia , Doenças do Sistema Imunitário/cirurgia , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Músculo Esquelético/cirurgia , Miofibrilas/metabolismo , Miofibrilas/patologia , Necrose/metabolismo , Necrose/patologia , Estudos Prospectivos , Sensibilidade e Especificidade
17.
Oncotarget ; 7(15): 20016-32, 2016 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-26956048

RESUMO

Recently, the conserved intracellular digestion mechanism 'autophagy' has been considered to be involved in early tumorigenesis and its blockade proposed as an alternative treatment approach. However, there is an ongoing debate about whether blocking autophagy has positive or negative effects in tumor cells. Since there is only poor data about the clinico-pathological relevance of autophagy in gliomas in vivo, we first established a cell culture based platform for the in vivo detection of the autophago-lysosomal components. We then investigated key autophagosomal (LC3B, p62, BAG3, Beclin1) and lysosomal (CTSB, LAMP2) molecules in 350 gliomas using immunohistochemistry, immunofluorescence, immunoblotting and qPCR. Autophagy was induced pharmacologically or by altering oxygen and nutrient levels. Our results show that autophagy is enhanced in astrocytomas as compared to normal CNS tissue, but largely independent from the WHO grade and patient survival. A strong upregulation of LC3B, p62, LAMP2 and CTSB was detected in perinecrotic areas in glioblastomas suggesting micro-environmental changes as a driver of autophagy induction in gliomas. Furthermore, glucose restriction induced autophagy in a concentration-dependent manner while hypoxia or amino acid starvation had considerably lesser effects. Apoptosis and autophagy were separately induced in glioma cells both in vitro and in vivo. In conclusion, our findings indicate that autophagy in gliomas is rather driven by micro-environmental changes than by primary glioma-intrinsic features thus challenging the concept of exploitation of the autophago-lysosomal network (ALN) as a treatment approach in gliomas.


Assuntos
Autofagia , Biomarcadores Tumorais/metabolismo , Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Lisossomos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1/metabolismo , Neoplasias Encefálicas/metabolismo , Catepsina B/metabolismo , Criança , Pré-Escolar , Feminino , Seguimentos , Glioma/metabolismo , Humanos , Lactente , Recém-Nascido , Proteína 2 de Membrana Associada ao Lisossomo/metabolismo , Masculino , Proteínas Associadas aos Microtúbulos/metabolismo , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Prognóstico , Proteínas de Ligação a RNA/metabolismo , Células Tumorais Cultivadas , Adulto Jovem
18.
Biomed Res Int ; 2015: 462592, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26550569

RESUMO

TMEM70 is involved in the biogenesis of mitochondrial ATP synthase and mutations in the TMEM70 gene impair oxidative phosphorylation. Herein, we report on pathology and treatment of ATP synthase deficiency in four siblings. A consanguineous family of Roma (Gipsy) ethnic origin gave birth to 6 children of which 4 were affected presenting with dysmorphic features, failure to thrive, cardiomyopathy, metabolic crises, and 3-methylglutaconic aciduria as clinical symptoms. Genetic testing revealed a homozygous mutation (c.317-2A>G) in the TMEM70 gene. While light microscopy was unremarkable, ultrastructural investigation of muscle tissue revealed accumulation of swollen degenerated mitochondria with lipid crystalloid inclusions, cristae aggregation, and exocytosis of mitochondrial material. Biochemical analysis of mitochondrial complexes showed an almost complete ATP synthase deficiency. Despite harbouring the same mutation, the clinical outcome in the four siblings was different. Two children died within 60 h after birth; the other two had recurrent life-threatening metabolic crises but were successfully managed with supplementation of anaplerotic amino acids, lipids, and symptomatic treatment during metabolic crisis. In summary, TMEM70 mutations can cause distinct ultrastructural mitochondrial degeneration and almost complete deficiency of ATP synthase but are still amenable to treatment.


Assuntos
Proteínas de Membrana/genética , Mitocôndrias/patologia , Doenças Mitocondriais/genética , Doenças Mitocondriais/patologia , Proteínas Mitocondriais/genética , ATPases Mitocondriais Próton-Translocadoras/deficiência , Polimorfismo de Nucleotídeo Único/genética , Adolescente , Criança , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Mitocôndrias/enzimologia , Mitocôndrias/ultraestrutura , Doenças Mitocondriais/terapia , ATPases Mitocondriais Próton-Translocadoras/genética , Resultado do Tratamento
19.
BMC Neurol ; 15: 103, 2015 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-26141177

RESUMO

BACKGROUND: Hereditary diffuse leukodystrophy with spheroids is a rare type of leukoencephalopathy. Mutations in the colony stimulating factor 1 receptor have recently been identified to be the cause of this microgliopathy. Clinical and radiological presentation can often misguide physicians during the diagnosis of patients with this underdiagnosed disease. CASE PRESENTATION: We present a 29 year-old woman with a rapid course of hereditary diffuse leukodystrophy with spheroids. She mainly showed cognitive impairment and severe motor dysfunctions. Her MRI showed spotted and confluent hyperintensities of the white matter on T2-weighted images involving the corticospinal tract as well as the corpus callosum. Further, those lesions showed striking restricted diffusion. As this restricted diffusion in all areas showing signs of leukoencephalopathy was so impressive we searched Medline for these terms and got hereditary diffuse leukodystrophy with spheroids as one of the first results. After a comprehensive diagnostic workup and exclusion of other leukoencephalopathies, stereotactic biopsy and genetic testing confirmed the diagnosis. CONCLUSION: This case points out at two important features of hereditary diffuse leukodystrophy with spheroids being spotted and/or confluent leukoencephalopathy with areas of restricted diffusion. This might help to identify more patients with this underdiagnosed disease. Moreover, the rapid clinical course in our patient raises the question whether the relatively pronounced areas of restricted diffusion are indicative of a more acute progression of the disease.


Assuntos
Imageamento por Ressonância Magnética , Receptor de Fator Estimulador de Colônias de Macrófagos/genética , Adulto , Transtornos Cognitivos/diagnóstico , Corpo Caloso/patologia , Progressão da Doença , Feminino , Humanos , Leucoencefalopatias/diagnóstico , Mutação , Tratos Piramidais/patologia
20.
Oncotarget ; 6(16): 14537-44, 2015 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-25966341

RESUMO

BACKGROUND: Hypoxia is a key driver for infiltrative growth in experimental gliomas. It has remained elusive whether tumor hypoxia in glioblastoma patients contributes to distant or diffuse recurrences. We therefore investigated the influence of perioperative cerebral ischemia on patterns of progression in glioblastoma patients. METHODS: We retrospectively screened MRI scans of 245 patients with newly diagnosed glioblastoma undergoing resection for perioperative ischemia near the resection cavity. 46 showed relevant ischemia nearby the resection cavity. A control cohort without perioperative ischemia was generated by a 1:1 matching using an algorithm based on gender, age and adjuvant treatment. Both cohorts were analyzed for patterns of progression by a blinded neuroradiologist. RESULTS: The percentage of diffuse or distant recurrences at first relapse was significantly higher in the cohort with perioperative ischemia (61.1%) compared to the control cohort (19.4%). The results of the control cohort matched well with historical data. The change in patterns of progression was not associated with a difference in survival. CONCLUSIONS: This study reveals an unrecognized association of perioperative cerebral ischemia with distant or diffuse recurrence in glioblastoma. It is the first clinical study supporting the concept that hypoxia is a key driver of infiltrative tumor growth in glioblastoma patients.


Assuntos
Neoplasias Encefálicas/complicações , Hipóxia Celular/fisiologia , Glioblastoma/complicações , Adulto , Idoso , Isquemia Encefálica , Neoplasias Encefálicas/mortalidade , Neoplasias Encefálicas/patologia , Estudos de Coortes , Progressão da Doença , Intervalo Livre de Doença , Feminino , Glioblastoma/mortalidade , Glioblastoma/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Período Perioperatório , Estudos Retrospectivos , Análise de Sobrevida
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