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1.
Biomed Eng Online ; 23(1): 43, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38654246

RESUMEN

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.


Asunto(s)
Parpadeo , Enfermedad de Parkinson , Grabación en Video , Humanos , Enfermedad de Parkinson/fisiopatología , Enfermedad de Parkinson/tratamiento farmacológico , Masculino , Femenino , Anciano , Persona de Mediana Edad , Procesamiento de Imagen Asistido por Computador/métodos , Estudios de Casos y Controles
2.
Nature ; 555(7697): 469-474, 2018 03 22.
Artículo en Inglés | MEDLINE | ID: mdl-29539639

RESUMEN

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.


Asunto(s)
Neoplasias del Sistema Nervioso Central/diagnóstico , Neoplasias del Sistema Nervioso Central/genética , Metilación de ADN , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Sistema Nervioso Central/clasificación , Neoplasias del Sistema Nervioso Central/patología , Niño , Preescolar , Estudios de Cohortes , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Aprendizaje Automático no Supervisado , Adulto Joven
3.
Sensors (Basel) ; 22(20)2022 Oct 20.
Artículo en Inglés | MEDLINE | ID: mdl-36298342

RESUMEN

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.


Asunto(s)
Enfermedad de Parkinson , Temblor , Humanos , Temblor/tratamiento farmacológico , Temblor/diagnóstico , Enfermedad de Parkinson/tratamiento farmacológico , Inteligencia Artificial , Movimiento , Mano
4.
Acta Neuropathol ; 140(2): 183-208, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32529267

RESUMEN

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.


Asunto(s)
Barrera Hematoencefálica , Subunidad alfa del Factor 1 Inducible por Hipoxia/metabolismo , Meningitis Neumocócica , Streptococcus pneumoniae , Migración Transendotelial y Transepitelial/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Animales , Barrera Hematoencefálica/metabolismo , Femenino , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Factor A de Crecimiento Endotelial Vascular/metabolismo
5.
BMC Pediatr ; 20(1): 399, 2020 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-32838761

RESUMEN

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.


Asunto(s)
Enfermedad de Hirschsprung , Biopsia , Colinérgicos , Enfermedad de Hirschsprung/diagnóstico , Histocitoquímica , Humanos , Intestinos , Recto
6.
J Neurochem ; 143(5): 467-488, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28869766

RESUMEN

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.


Asunto(s)
Enfermedad de Alzheimer/inmunología , Péptidos beta-Amiloides/inmunología , Enfermedad de Parkinson/inmunología , Tauopatías/inmunología , Vacunación , Enfermedad de Alzheimer/prevención & control , Péptidos beta-Amiloides/metabolismo , Animales , Humanos , Enfermedad de Parkinson/prevención & control , Tauopatías/metabolismo , Vacunación/métodos , alfa-Sinucleína/metabolismo
7.
BMC Neurol ; 17(1): 212, 2017 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-29216848

RESUMEN

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.


Asunto(s)
Adenocarcinoma , Neoplasias Colorrectales , Infecciones por Fusobacterium/diagnóstico , Fusobacterium/patogenicidad , Región Lumbosacra/patología , Meningitis Bacterianas/diagnóstico , Meningocele/diagnóstico , Anciano , Femenino , Humanos , Región Lumbosacra/diagnóstico por imagen , Imagen por Resonancia Magnética
8.
Stereotact Funct Neurosurg ; 92(3): 129-39, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24776650

RESUMEN

BACKGROUND: In nonresectable glioblastoma (GBM), stereotactic biopsies are performed to retrieve tissue for diagnostic purposes. The analysis of O6-methylguanine-DNA methyltransferase (MGMT) promoter methylation adds prognostic and predictive information. OBJECTIVES: The aim of the study was to detect confounding factors that limit the number of conclusive MGMT promoter methylation results. METHODS: We analyzed 71 consecutive GBM patients undergoing stereotactic biopsy on whom MGMT analysis was performed by methylation-specific polymerase chain reaction. Specimens were correlated to imaging by coregistration and prospective documentation of biopsy localization. Our findings were validated in an additional 62 GBM stereotactic biopsies. RESULTS: Our results demonstrate that the best MGMT promoter methylation results were obtained from samples (n = 71) taken in a tangential manner from tumor areas showing contrast enhancement in magnetic resonance imaging. In the additional validation series of 62 stereotactically biopsied GBM, we were able to increase the rate of conclusive MGMT promoter methylation results from 76.1 to 85.48% by strictly planning the route of biopsy in a tangential manner if possible. CONCLUSIONS: These results underline that within the contrast-enhanced tumor part, choosing the trajectory in a tangential manner increases the diagnostic yield for conclusive MGMT promoter methylation analyses in stereotactic biopsies as a basis for patient stratification and individualized therapy.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Metilasas de Modificación del ADN/metabolismo , Enzimas Reparadoras del ADN/metabolismo , Glioblastoma/diagnóstico , Glioblastoma/metabolismo , Regiones Promotoras Genéticas/fisiología , Técnicas Estereotáxicas , Proteínas Supresoras de Tumor/metabolismo , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/genética , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Femenino , Glioblastoma/genética , Humanos , Masculino , Metilación , Persona de Mediana Edad , Estudios Prospectivos , Sistema de Registros , Estudios Retrospectivos , Técnicas Estereotáxicas/normas , Proteínas Supresoras de Tumor/genética
9.
Biomolecules ; 12(3)2022 03 18.
Artículo en Inglés | MEDLINE | ID: mdl-35327661

RESUMEN

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.


Asunto(s)
Enfermedad de Parkinson , alfa-Sinucleína , Ensayo de Inmunoadsorción Enzimática/métodos , Células HEK293 , Humanos , Neuronas/metabolismo , Enfermedad de Parkinson/metabolismo , alfa-Sinucleína/metabolismo
10.
Geroscience ; 43(5): 2547-2559, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34241807

RESUMEN

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.


Asunto(s)
Rendimiento Atlético , Aprendizaje Automático , Humanos
11.
J Parkinsons Dis ; 11(2): 833-842, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33682733

RESUMEN

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.


Asunto(s)
Enfermedad de Parkinson , Medios de Comunicación Sociales , Humanos , Difusión de la Información , Grabación en Video
12.
J Gerontol A Biol Sci Med Sci ; 76(8): 1376-1381, 2021 07 13.
Artículo en Inglés | MEDLINE | ID: mdl-33606016

RESUMEN

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.


Asunto(s)
Envejecimiento/fisiología , Rendimiento Atlético , Rendimiento Físico Funcional , Atletismo/fisiología , Atletas/estadística & datos numéricos , Rendimiento Atlético/fisiología , Rendimiento Atlético/estadística & datos numéricos , Macrodatos , Estudios Transversales , Humanos , Longevidad/fisiología , Estudios Longitudinales , Masculino , Persona de Mediana Edad , Modelación Específica para el Paciente , Suecia/epidemiología
13.
Pathol Res Pract ; 216(1): 152728, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31784096

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas/genética , Metilasas de Modificación del ADN/genética , Enzimas Reparadoras del ADN/genética , Glioblastoma/genética , Proteínas Supresoras de Tumor/genética , Adulto , Anciano , Metilación de ADN/genética , Femenino , Glioblastoma/patología , Humanos , Masculino , Persona de Mediana Edad , Regiones Promotoras Genéticas/genética , Proteínas Supresoras de Tumor/metabolismo
14.
J Exp Med ; 214(2): 423-437, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-28082356

RESUMEN

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.


Asunto(s)
Proteínas Portadoras/metabolismo , Quinasa I-kappa B/fisiología , Inflamación/metabolismo , Animales , Proteínas Relacionadas con la Autofagia , Proteínas Portadoras/química , Caspasa 12/fisiología , Colitis/prevención & control , Estrés del Retículo Endoplásmico , Endorribonucleasas/fisiología , Interleucina-18/metabolismo , Ratones , FN-kappa B/fisiología , Proteína Adaptadora de Señalización NOD2/fisiología , Proteínas Serina-Treonina Quinasas/fisiología , Estabilidad Proteica , Respuesta de Proteína Desplegada
15.
Neuromuscul Disord ; 26(4-5): 283-91, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27020463

RESUMEN

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.


Asunto(s)
Capilares/metabolismo , Capilares/patología , Complejo de Ataque a Membrana del Sistema Complemento/metabolismo , Músculo Esquelético/irrigación sanguínea , Adulto , Anciano , Anciano de 80 o más Años , Biopsia , Dermatomiositis/diagnóstico , Dermatomiositis/metabolismo , Dermatomiositis/patología , Dermatomiositis/cirugía , Diagnóstico Diferencial , Femenino , Estudios de Seguimiento , Humanos , Enfermedades del Sistema Inmune/diagnóstico , Enfermedades del Sistema Inmune/metabolismo , Enfermedades del Sistema Inmune/patología , Enfermedades del Sistema Inmune/cirugía , Inmunohistoquímica , Masculino , Persona de Mediana Edad , Músculo Esquelético/metabolismo , Músculo Esquelético/patología , Músculo Esquelético/cirugía , Miofibrillas/metabolismo , Miofibrillas/patología , Necrosis/metabolismo , Necrosis/patología , Estudios Prospectivos , Sensibilidad y Especificidad
16.
Oncotarget ; 7(15): 20016-32, 2016 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-26956048

RESUMEN

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.


Asunto(s)
Autofagia , Biomarcadores de Tumor/metabolismo , Neoplasias Encefálicas/diagnóstico , Glioma/diagnóstico , Lisosomas/metabolismo , Proteínas Adaptadoras Transductoras de Señales/metabolismo , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Proteínas Reguladoras de la Apoptosis/metabolismo , Beclina-1/metabolismo , Neoplasias Encefálicas/metabolismo , Catepsina B/metabolismo , Niño , Preescolar , Femenino , Estudios de Seguimiento , Glioma/metabolismo , Humanos , Lactante , Recién Nacido , Proteína 2 de la Membrana Asociada a los Lisosomas/metabolismo , Masculino , Proteínas Asociadas a Microtúbulos/metabolismo , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Proteínas de Unión al ARN/metabolismo , Células Tumorales Cultivadas , Adulto Joven
17.
Oncotarget ; 6(16): 14537-44, 2015 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-25966341

RESUMEN

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.


Asunto(s)
Neoplasias Encefálicas/complicaciones , Hipoxia de la Célula/fisiología , Glioblastoma/complicaciones , Adulto , Anciano , Isquemia Encefálica , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Estudios de Cohortes , Progresión de la Enfermedad , Supervivencia sin Enfermedad , Femenino , Glioblastoma/mortalidad , Glioblastoma/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Periodo Perioperatorio , Estudios Retrospectivos , Análisis de Supervivencia
18.
Biomed Res Int ; 2015: 462592, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26550569

RESUMEN

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.


Asunto(s)
Proteínas de la Membrana/genética , Mitocondrias/patología , Enfermedades Mitocondriales/genética , Enfermedades Mitocondriales/patología , Proteínas Mitocondriales/genética , ATPasas de Translocación de Protón Mitocondriales/deficiencia , Polimorfismo de Nucleótido Simple/genética , Adolescente , Niño , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Mitocondrias/enzimología , Mitocondrias/ultraestructura , Enfermedades Mitocondriales/terapia , ATPasas de Translocación de Protón Mitocondriales/genética , Resultado del Tratamiento
19.
Brain Pathol ; 25(4): 491-504, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25175718

RESUMEN

The macrophage migration inhibitory factor (MIF) receptor CD74 is overexpressed in various neoplasms, mainly in hematologic tumors, and currently investigated in clinical studies. CD74 is quickly internalized and recycles after antibody binding, therefore it constitutes an attractive target for antibody-based treatment strategies. CD74 has been further described as one of the most up-regulated molecules in human glioblastomas. To assess the potential relevance for anti-CD74 treatment, we determined the cellular source and clinicopathologic relevance of CD74 expression in human gliomas by immunohistochemistry, immunofluorescence, immunoblotting, cell sorting analysis and quantitative polymerase chain reaction (qPCR). Furthermore, we fractionated glioblastoma cells and glioma-associated microglia/macrophages (GAMs) from primary tumors and compared CD74 expression in cellular fractions with whole tumor lysates. Our results show that CD74 is restricted to GAMs in vivo, while being absent in tumor cells, the latter strongly expressing its ligand MIF. Most interestingly, a higher amount of CD74-positive GAMs was associated with beneficial patient survival constituting an independent prognostic parameter and with an anti-tumoral M1 polarization. In summary, CD74 expression in human gliomas is restricted to GAMs and positively associated with patient survival. In conclusion, CD74 represents a positive prognostic marker most probably because of its association with an M1-polarized immune milieu in high-grade gliomas.


Asunto(s)
Neoplasias Encefálicas , Antígeno CD47/metabolismo , Glioma , Macrófagos/metabolismo , Microglía/metabolismo , Regulación hacia Arriba/fisiología , Neoplasias Encefálicas/metabolismo , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/patología , Antígeno CD47/genética , Proteínas de Unión al Calcio , Línea Celular Tumoral , Proteínas de Unión al ADN/metabolismo , Femenino , Citometría de Flujo , Proteína Ácida Fibrilar de la Glía/metabolismo , Glioma/metabolismo , Glioma/mortalidad , Glioma/patología , Humanos , Estimación de Kaplan-Meier , Masculino , Análisis por Micromatrices , Proteínas de Microfilamentos , ARN Mensajero/metabolismo
20.
Neuro Oncol ; 16(11): 1469-77, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-25155358

RESUMEN

BACKGROUND: Experimental findings have suggested that human cytomegalovirus (HCMV) infection of tumor cells may exert oncomodulatory effects that enhance tumor malignancy. However, controversial findings have been published on the presence of HCMV in malignant tumors. Here, we present the first study that systematically investigates HCMV infection in human nervous system tumors by highly sensitive immunohistochemistry in correlation with the HCMV serostatus of the patients. METHODS: Immunohistochemical and quantitative PCR-based methods to detect different HCMV antigens and genomic HCMV DNA were optimized prior to the investigation of pathological samples. Moreover, the pathological results were matched with the HCMV serostatus of the patients. RESULTS: HCMV immediate-early, late, and pp65 antigens could be detected in single cells from HCMV strain Hi91-infected UKF-NB-4 neuroblastoma cells after 1:1024 dilution with noninfected UKF-NB-4 cells. Genomic HCMV DNA could be detected in copy numbers as low as 430 copies/mL. However, we did not detect HCMV in tumors from a cohort of 123 glioblastoma, medulloblastoma, or neuroblastoma patients. Notably, we detected nonspecifically positive staining in tumor tissues of HCMV seropositive and seronegative glioblastoma patients. The HCMV serostatus of 67 glioblastoma patients matched the general epidemiological prevalence data for Western countries (72% of female and 57% of male glioblastoma patients were HCMV seropositive). Median survival was not significantly different in HCMV seropositive versus seronegative glioblastoma patients. CONCLUSIONS: The prevalence of HCMV-infected tumor cells may be much lower than previously reported based on highly sensitive detection methods.


Asunto(s)
Neoplasias Encefálicas/diagnóstico , Infecciones por Citomegalovirus/diagnóstico , Citomegalovirus/aislamiento & purificación , Glioblastoma/diagnóstico , Neuroblastoma/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , Neoplasias Encefálicas/epidemiología , Neoplasias Encefálicas/mortalidad , Neoplasias Encefálicas/virología , Estudios de Casos y Controles , Citomegalovirus/genética , Infecciones por Citomegalovirus/epidemiología , Infecciones por Citomegalovirus/mortalidad , Infecciones por Citomegalovirus/virología , ADN Viral/genética , Femenino , Estudios de Seguimiento , Glioblastoma/epidemiología , Glioblastoma/mortalidad , Glioblastoma/virología , Humanos , Técnicas para Inmunoenzimas , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Neuroblastoma/epidemiología , Neuroblastoma/mortalidad , Neuroblastoma/virología , Pronóstico , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Seroepidemiológicos , Tasa de Supervivencia
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