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1.
Cancer Immunol Immunother ; 72(6): 1603-1618, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-36562826

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is an immunologically vulnerable tumor entity, and immune checkpoint inhibitors are now widely used to treat patients with advanced disease. Whether and to what extent immune responses in ccRCC are shaped by genetic alterations, however, is only beginning to emerge. In this proof-of-concept study, we performed a detailed correlative analysis of the mutational and immunological landscapes in a series of 23 consecutive kidney cancer patients. We discovered that a high infiltration with CD8 + T cells was not dependent on the number of driver mutations but rather on the presence of specific mutational events, namely pathogenic mutations in PTEN or BAP1. This observation encouraged us to compare mechanisms of T cell suppression in the context of four different genetic patterns, i.e., the presence of multiple drivers, a PTEN or BAP1 mutation, or the absence of detectable driver mutations. We found that ccRCCs harboring a PTEN or BAP1 mutation showed the lowest level of Granzyme B positive tumor-infiltrating lymphocytes (TILs). A multiplex immunofluorescence analysis revealed a significant number of CD8 + TILs in the vicinity of CD68 + macrophages/monocytes in the context of a BAP1 mutation but not in the context of a PTEN mutation. In line with this finding, direct interactions between CD8 + TILs and CD163 + M2-polarized macrophages were found in BAP1-mutated ccRCC but not in tumors with other mutational patterns. While an absence of driver mutations was associated with more CD8 + TILs in the vicinity of FOXP3 + Tregs and CD68 + monocytes/macrophages, the presence of multiple driver mutations was, to our surprise, not found to be strongly associated with immunosuppressive mechanisms. Our results highlight the role of genetic alterations in shaping the immunological landscape of ccRCC. We discovered a remarkable heterogeneity of mechanisms that can lead to T cell suppression, which supports the need for personalized immune oncological approaches.


Asunto(s)
Carcinoma de Células Renales , Neoplasias Renales , Humanos , Carcinoma de Células Renales/patología , Proteínas de Unión al ADN/genética , Neoplasias Renales/patología , Factores de Transcripción/genética , Mutación , Pronóstico , Proteínas Supresoras de Tumor/genética , Ubiquitina Tiolesterasa/genética , Fosfohidrolasa PTEN/genética
2.
Neuroimage ; 230: 117778, 2021 04 15.
Artículo en Inglés | MEDLINE | ID: mdl-33497775

RESUMEN

Information from Magnetic Resonance Imaging (MRI) is useful for diagnosis and treatment management of human neurological patients. MRI monitoring might also prove useful for non-human animals involved in neuroscience research provided that MRI is available and feasible and that there are no MRI contra-indications precluding scanning. However, MRI monitoring is not established in macaques and a resource is urgently needed that could grow with scientific community contributions. Here we show the utility and potential benefits of MRI-based monitoring in a few diverse cases with macaque monkeys. We also establish a PRIMatE MRI Monitoring (PRIME-MRM) resource within the PRIMatE Data Exchange (PRIME-DE) and quantitatively compare the cases to normative information drawn from MRI data from typical macaques in PRIME-DE. In the cases, the monkeys presented with no or mild/moderate clinical signs, were well otherwise and MRI scanning did not present a significant increase in welfare impact. Therefore, they were identified as suitable candidates for clinical investigation, MRI-based monitoring and treatment. For each case, we show MRI quantification of internal controls in relation to treatment steps and comparisons with normative data in typical monkeys drawn from PRIME-DE. We found that MRI assists in precise and early diagnosis of cerebral events and can be useful for visualising, treating and quantifying treatment response. The scientific community could now grow the PRIME-MRM resource with other cases and larger samples to further assess and increase the evidence base on the benefits of MRI monitoring of primates, complementing the animals' clinical monitoring and treatment regime.


Asunto(s)
Encéfalo/diagnóstico por imagen , Análisis de Datos , Imagen por Resonancia Magnética/métodos , Enfermedades del Sistema Nervioso/diagnóstico por imagen , Animales , Estudios de Casos y Controles , Enfermedades Desmielinizantes/diagnóstico por imagen , Enfermedades Desmielinizantes/terapia , Infecciones/diagnóstico por imagen , Infecciones/terapia , Macaca mulatta , Masculino , Debilidad Muscular/diagnóstico por imagen , Debilidad Muscular/terapia , Enfermedades del Sistema Nervioso/terapia
3.
Cereb Cortex ; 30(6): 3467-3482, 2020 05 18.
Artículo en Inglés | MEDLINE | ID: mdl-31867667

RESUMEN

Neocortex development depends on neural stem cell proliferation, cell differentiation, neurogenesis, and neuronal migration. Cytoskeletal regulation is critical for all these processes, but the underlying mechanisms are only poorly understood. We previously implicated the cytoskeletal regulator profilin1 in cerebellar granule neuron migration. Since we found profilin1 expressed throughout mouse neocortex development, we here tested the hypothesis that profilin1 is crucial for neocortex development. We found no evidence for impaired neuron migration or layering in the neocortex of profilin1 mutant mice. However, proliferative activity at basal positions was doubled in the mutant neocortex during mid-neurogenesis, with a drastic and specific increase in basal Pax6+ cells indicative for elevated numbers of basal radial glia (bRG). This was accompanied by transiently increased neurogenesis and associated with mild invaginations resembling rudimentary neocortex folds. Our data are in line with a model in which profilin1-dependent actin assembly controls division of apical radial glia (aRG) and thereby the fate of their progenies. Via this mechanism, profilin1 restricts cell delamination from the ventricular surface and, hence, bRG production and thereby controls neocortex development in mice. Our data support the radial cone hypothesis" claiming that elevated bRG number causes neocortex folds.


Asunto(s)
Actinas/metabolismo , Proliferación Celular/genética , Células Ependimogliales/citología , Neocórtex/embriología , Neurogénesis/genética , Profilinas/genética , Citoesqueleto de Actina , Animales , División Celular/genética , Ratones , Mutación , Células-Madre Neurales
4.
Acta Paediatr ; 110(12): 3315-3321, 2021 12.
Artículo en Inglés | MEDLINE | ID: mdl-34525232

RESUMEN

AIM: It can be challenging to distinguish COVID-19 in children from other common infections. We set out to determine the rate at which children consulting a primary care paediatrician with an acute infection are infected with SARS-CoV-2 and to compare distinct findings. METHOD: In seven out-patient clinics, children aged 0-13 years with any new respiratory or gastrointestinal symptoms and presumed infection were invited to be tested for SARS-CoV-2. Factors that were correlated with testing positive were determined. Samples were collected from 25 January 2021 to 01 April 2021. RESULTS: Seven hundred and eighty-three children participated in the study (median age 3 years and 0 months, range 1 month to 12 years and 11 months). Three hundred and fifty-eight were female (45.7%). SARS-CoV-2 RNA was detected in 19 (2.4%). The most common symptoms in children with as well as without detectable SARS-CoV-2 RNA were rhinitis, fever and cough. Known recent exposure to a case of COVID-19 was significantly correlated with testing positive, but symptoms or clinical findings were not. CONCLUSION: COVID-19 among the children with symptoms of an acute infection was uncommon, and the clinical presentation did not differ significantly between children with and without evidence of an infection with SARS-CoV-2.


Asunto(s)
COVID-19 , Niño , Femenino , Fiebre , Humanos , Lactante , Atención Primaria de Salud , ARN Viral , SARS-CoV-2
5.
J Anim Physiol Anim Nutr (Berl) ; 104(2): 462-469, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31943416

RESUMEN

The aim of the study was to determine the abomasal emptying rate (AER) of calves suffering from naturally occurring diarrhoea compared with that of healthy calves. Furthermore, the effects of an oral rehydration solution (ORS) mixed into milk replacer on the AER were determined. Acetaminophen absorption test (APAT) was performed to estimate the AER. Sixty Holstein-Frisian calves (age < 14 days) were included in the study and divided into groups as follows: healthy calves (H; n = 16), healthy calves fed with ORS (HORS; n = 14), diarrhoeic calves (D; n = 15) and diarrhoeic calves fed with ORS (DORS; n = 15). For the APAT, the calves were fed 2 L of milk replacer containing 50 mg acetaminophen (AP)/kg body weight. Venous blood samples were collected before and after milk replacer and AP intake in 30-60 min intervals for 12 hr. During the APAT, no significant differences in median maximum acetaminophen concentration (Cmax ) were observed among all groups. Time to reach maximum acetaminophen concentration (Tmax ) in DORS (median 390 min, 25/75 quartiles: 300/480 min) was significantly higher compared with that in H (median: 270 min 25/75 quartiles: 210/315 min) and HORS (median: 300 min (25/75 quartiles: 240/360 min). Non-linear regression revealed that the calculated abomasal half-life (AP t1/2 ) tended to be delayed in DORS (median: 652 min, 25/75 quartiles: 445/795 min, p = .10). The area under the AP curve values (AUC) from 0 to 120 min and 0 to 240 min of the observation period were significantly higher in H than D and DORS. In conclusion, significant differences in the AER indices reflected delayed abomasal emptying in diarrhoeic calves. Furthermore, the hypertonic ORS tended to have an additive delaying impact on the AER, which needs attention for the feeding management of diarrhoeic calves.


Asunto(s)
Abomaso/efectos de los fármacos , Enfermedades de los Bovinos/terapia , Diarrea/veterinaria , Vaciamiento Gástrico , Soluciones para Rehidratación/administración & dosificación , Acetaminofén/toxicidad , Animales , Animales Lactantes , Bovinos , Diarrea/inducido químicamente , Diarrea/terapia , Sustitutos de la Leche
6.
Mol Pharm ; 15(2): 548-559, 2018 02 05.
Artículo en Inglés | MEDLINE | ID: mdl-29298479

RESUMEN

Grapefruit juice (GFJ) is known to affect the bioavailability of drugs in different ways. Despite the influence on gastrointestinal enzymes and transporters, the influence on gastrointestinal fluid kinetics is regarded to be relevant for the absorption of several drugs. Thus, it was the aim of this pilot study to investigate the gastric and intestinal volumes after intake of GFJ compared to isocaloric fructose and glucose solutions and water. The gastric and small intestinal volume kinetics after intake of 240 mL of GFJ, 10.6% fructose solution, 10.6% glucose solution, and water were investigated with magnetic resonance imaging in a four-way crossover study in six healthy human volunteers. The carbohydrate content of the administered beverages was quantified by high-performance liquid chromatography. Even with the small sample size of this pilot study, the gastric emptying of GFJ and the glucose solution was significantly slower than that of water. The fructose solution had only a slightly delayed gastric emptying. Small bowel water content was increased by administration of GFJ and fructose solution, whereas it was decreased by glucose compared to the administration of pure water. At 80 min the small bowel water content after GFJ was twice as high as the small bowel water content after administration of water. The observed influence of GFJ on gastrointestinal fluid kinetics may explain certain phenomena in drugs pharmacokinetics. The effect is double edged, as the slower gastric emptying and increased intestinal filling can lead to enhanced or altered absorption. Due to the comparability of fruit juices, a general effect of fruit juices on gastrointestinal volumes is likely.


Asunto(s)
Citrus paradisi , Interacciones Alimento-Droga , Jugos de Frutas y Vegetales , Vaciamiento Gástrico , Secreciones Intestinales/química , Adulto , Disponibilidad Biológica , Estudios Cruzados , Femenino , Fructosa/administración & dosificación , Glucosa/administración & dosificación , Voluntarios Sanos , Humanos , Intestino Delgado , Imagen por Resonancia Magnética , Masculino , Proyectos Piloto , Estómago/diagnóstico por imagen , Agua , Adulto Joven
7.
AAPS PharmSciTech ; 19(7): 2843-2850, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29845498

RESUMEN

Despite extensive research in the field of gastroretentive dosage forms, this "holy grail" of oral drug delivery yet remained an unmet goal. Especially under fasting conditions, the reproducible retention of dosage forms in the stomach seems to be an impossible task. This is why such systems are often advised to be taken together with food. But also the postprandial motility can contribute significantly to the failure of gastroretentive dosage forms. To investigate the influence of postprandial pressure conditions on drug release from such systems, we used a novel in vitro dissolution tool, the dissolution stress test device. With the aid of this device, we simulated three different intragastric pressure profiles that may occur after postprandial intake. These transit scenarios were based on recently obtained, postprandial SmartPill® data. The tested systems, Glumetza® 1000 and Madopar® HBS 125, are marketed dosage forms that are based on different approaches to achieve proper gastric retention. All three transit scenarios revealed a highly pressure-sensitive drug release behavior, for both drugs. For Madopar® HBS 125, nearly complete drug release was observed even after early occurring pressures. Glumetza® 1000 seemed to be more resistant to these, most likely due to incomplete wetting of the system. On the contrary to these findings, data from standard dissolution tests using the paddle apparatus displayed controlled drug release for both systems for about 6 h. Based on these results, it can be doubted that established gastroretentive systems stay intact over a longer period of time, even under postprandial conditions.


Asunto(s)
Benserazida/farmacocinética , Liberación de Fármacos/fisiología , Levodopa/farmacocinética , Periodo Posprandial/fisiología , Estómago/fisiología , Benserazida/administración & dosificación , Preparaciones de Acción Retardada/administración & dosificación , Preparaciones de Acción Retardada/metabolismo , Formas de Dosificación , Combinación de Medicamentos , Sistemas de Liberación de Medicamentos/métodos , Inhibidores Enzimáticos/administración & dosificación , Inhibidores Enzimáticos/farmacocinética , Ayuno/metabolismo , Humanos , Levodopa/administración & dosificación , Periodo Posprandial/efectos de los fármacos , Presión , Estómago/efectos de los fármacos
8.
Mol Pharm ; 14(12): 4272-4280, 2017 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-29064257

RESUMEN

The drug plasma profile after oral administration of immediate release dosage forms can be affected by the human gastrointestinal physiology, the formulation, and the drug itself. In this work, we investigated the in vivo and in vitro performance of two formulations (granules vs. tablet) containing the highly soluble drug N-Acetylcysteine (BCS class I). Thereby, special attention was paid to the effect of the dosage form and the coadministration of water on drug release. Interestingly, the in vivo results from a pharmacokinetic study with 11 healthy volunteers indicated that the drug plasma concentrations were comparable for the tablet given with water as well as for the granules given with and without water. In order to mechanistically understand this outcome, we used a biorelevant dissolution test device, the dynamic open flow-through test apparatus. With the aid of this test apparatus, we were able to simulate biorelevant parameters, such as gastric emptying, hydrodynamic flow as well as physical stress. By this, it was possible to mimic the intake conditions of the clinical trial (i.e., drug intake with and without water). Whereas the experiments in the USP paddle apparatus revealed differences between the two formulations, we could not observe significant differences in the release profiles of the two formulations by using the dynamic open flow-through test apparatus. Even by considering the different intake conditions, drug release was slow and amounted to around 30% until simulated gastric emptying. These results suggest that dissolution was irrespective of coadministered water and the formulation. Despite the high aqueous solubility of N-Acetylcysteine, the limiting factor for drug release was the slow dissolution rate in relation to the gastric emptying rate under simulated gastric conditions. Thus, in case of administration together with water, large amounts of the drug are still present in the stomach even after complete gastric emptying of the water. Consequently, the absorption of the drug is largely controlled by the nature of gastric emptying of the remaining drug. The data of this study indicated that the water emptying kinetics are only determining drug absorption if drug release is rapid enough. If this is not the case, physiological mechanisms, such as the migrating motor complex, play an important role for oral drug delivery.


Asunto(s)
Acetilcisteína/farmacocinética , Liberación de Fármacos , Vaciamiento Gástrico/fisiología , Técnicas In Vitro/instrumentación , Agua/fisiología , Absorción Fisiológica/fisiología , Acetilcisteína/administración & dosificación , Administración Oral , Adulto , Biofarmacia/instrumentación , Biofarmacia/métodos , Química Farmacéutica , Estudios Cruzados , Sistemas de Liberación de Medicamentos , Femenino , Interacciones Alimento-Droga/fisiología , Voluntarios Sanos , Humanos , Técnicas In Vitro/métodos , Masculino , Persona de Mediana Edad , Solubilidad , Comprimidos , Adulto Joven
9.
Mol Pharm ; 14(12): 4220-4232, 2017 12 04.
Artículo en Inglés | MEDLINE | ID: mdl-28621952

RESUMEN

This study aimed to gain further insight into the gastrointestinal disposition of the weakly acidic BCS class II drug diclofenac and the implications for systemic drug exposure in humans under fasted and fed state conditions. For this purpose, gastrointestinal and blood samples were collected from healthy volunteers after oral intake of a commercially available tablet of the potassium salt of diclofenac (i.e., Cataflam) in different prandial states. Subsequently, these in vivo data served as a reference for the evaluation of in vitro tools with different levels of complexity, i.e., a conventional USP II dissolution apparatus, a modified version of the dynamic open flow through test apparatus, and the TNO gastrointestinal model equipped with the recently developed advanced gastric compartment (TIMagc). In vivo data suggested impaired drug dissolution and/or immediate precipitation in the fasted stomach, linked to the acidity of the gastric environment. Similarly, a vast presence of solid drug material in the stomach was observed under fed state conditions, which could be attributed to a marked delay in intragastric tablet disintegration after drug intake with a meal. Emptying of solid drug from the stomach into the duodenum generally resulted in rapid intestinal drug (re)dissolution in both test conditions, explaining the absence of a food effect on the extent of overall systemic exposure for diclofenac. In vitro tools were found to be capable of predicting in vivo intraluminal (and systemic) disposition of this compound, the extent of which depended on the degree to which the dynamic nature of the gastrointestinal process(es) to be investigated was simulated.


Asunto(s)
Diclofenaco/farmacocinética , Liberación de Fármacos , Técnicas In Vitro/métodos , Absorción Intestinal/fisiología , Administración Oral , Adulto , Biofarmacia/instrumentación , Biofarmacia/métodos , Diclofenaco/administración & dosificación , Ayuno/fisiología , Femenino , Vaciamiento Gástrico/fisiología , Tracto Gastrointestinal/fisiología , Voluntarios Sanos , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro/instrumentación , Masculino , Periodo Posprandial/fisiología , Solubilidad , Comprimidos , Adulto Joven
10.
Ann Neurol ; 75(5): 759-70, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24777960

RESUMEN

OBJECTIVE: MRI-negative (MRI-) pharmacoresistant focal epilepsy (PFE) patients are most challenging for epilepsy surgical management. This study utilizes a voxel-based MRI postprocessing technique, implemented using a morphometric analysis program (MAP), aiming to facilitate detection of subtle focal cortical dysplasia (FCD) in MRI- patients. Furthermore, the study examines the concordance between MAP-identified regions and localization from magnetic source imaging (MSI). METHODS: Included in this retrospective study were 25 MRI- surgical patients. MAP was performed on T1-weighted MRI, with comparison to a normal database. The pertinence of MAP+ areas was confirmed by MSI, surgical outcome and pathology. Analyses of MAP and MSI were performed blindly from patients' clinical information and independently from each other. RESULTS: The detection rate of subtle changes by MAP was 48% (12/25). Once MAP+ areas were resected, patients were more likely to be seizure-free (p=0.02). There were no false positives in the 25 age-matched normal controls. Seven patients had a concordant MSI correlate. Patients in whom a concordant area was identified by both MAP and MSI had a significantly higher chance of achieving a seizure-free outcome following complete resection of this area (p=0.008). In the 9 resected MAP+ areas, pathology revealed FCD type IA in 7 and type IIB in 2. INTERPRETATION: MAP shows promise in identifying subtle FCD abnormalities and increasing the diagnostic yield of conventional MRI visual analysis in presurgical evaluation of PFE. Concordant MRI postprocessing and MSI analyses may lead to the noninvasive identification of a structurally and electrically abnormal subtle lesion that can be surgically targeted.


Asunto(s)
Epilepsia/diagnóstico , Epilepsia/cirugía , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Monitoreo Intraoperatorio/métodos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Electroencefalografía/métodos , Epilepsia/fisiopatología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Método Simple Ciego , Adulto Joven
11.
Urol Oncol ; 2024 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-38981801

RESUMEN

INTRODUCTION: Clear cell Renal Cell Carcinoma (ccRCC) has a poor prognosis once metastatic. However, certain metastatic sites have been reported to have a different impact on the patient prognosis. For example, patients with pancreatic metastases have a much more favorable prognosis than those with metastases to other organs. The biological basis for this observation remains poorly understood. The aim of this study was to characterize the immune landscape of pancreatic metastases and the corresponding primary tumors in order to identify possible immunological features that correlate with disease biology. PATIENTS AND METHODS: A detailed assessment of immune cell populations was performed using a total of 1,700 microscopic images from ccRCCs from 11 patients, their corresponding pancreatic metastases and ccRCCs from 10 patients without pancreatic metastases. Tumor specimens were stained for CD45, CD8, CD163 and FOXP3 and the densities of the respective immune cells were assessed semiquantitatively in the intratumoral and extratumoral compartment. Multispectral imaging was performed in selected tumors. RESULTS: We found that pancreatic metastases show the lowest intratumoral infiltration with CD8+ cytotoxic T lymphocytes of all tumor specimens analyzed. The frequency of CD8+ lymphocytes was on 1.9 fold lower in pancreatic metastases (median density 8.3 cells per field of view [FOV] = 1.23 mm2) when compared to the corresponding primary tumor (15.6 cells per FOV, P = 0.0002) and more than 3-fold lower when compared to ccRCCs without pancreatic metastases (27.2 cells per FOV, P = 0.0012). There was also a significantly reduced intratumoral infiltration with immunosuppressive FOXP3+ lymphocytes in pancreatic metastases (2.6 cells per FOV, P = 0.009) and corresponding primary tumors (2 cells per FOV, P = 0.028) when compared to ccRCCs without pancreatic metastases (5.6 cells per FOV). CONCLUSIONS: In this proof-of-concept study, we show that pancreatic metastases of ccRCC present with unique immunological features including a low intratumoral density of CD8+ and FOXP3+ lymphocytes. The low counts of CD8+ and FOXP3+ lymphocytes may reflect less aggressive features of ccRCC with pancreatic metastasis that may result in a more favorable patient prognosis.

12.
Epilepsia ; 54(2): 359-69, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23106128

RESUMEN

PURPOSE: To investigate the utility of magnetic source imaging (MSI) and ictal single photon emission computed tomography (SPECT), each compared with intracranial electroencephalography (EEG) (ICEEG), to localize the epileptogenic zone (EZ) and predict epilepsy surgery outcome in patients with nonlesional neocortical focal epilepsy. METHODS: Studied were 14 consecutive patients with nonlesional neocortical epilepsy who underwent presurgical evaluation including ICEEG, positive MSI, and localizing subtraction Ictal SPECT coregistered to MRI (SISCOM) analysis. Follow-up after epilepsy surgery was ≥ 24 months. ICEEG, MSI, and SPECT results were classified using a sublobar classification. KEY FINDINGS: Of 14 patients, 6 (42.9%) became seizure-free after surgery. Sublobar ICEEG focus was completely resected in 11 patients; 5 (45.5%) of them became seizure- free. Concordance of ICEEG and MSI and complete focus resection was found in 5 (35.7%) patients; 80% of them became seizure-free. Sublobar ICEEG-MSI concordance and complete focus resection significantly increased the chance of seizure freedom after epilepsy surgery (p = 0.038). In contrast, of the 6 patients (42.9%) with concordant ICEEG and SISCOM and complete focus resection, only 66.7% became seizure-free (p = 0.138). Assuming concordant results, the additive value to ICEEG alone for localizing the EZ is higher with ICEEG-MSI (odds ratio 14) compared to ICEEG-SISCOM (odds ratio 6). SIGNIFICANCE: This study shows that combination of MSI and/or SISCOM with ICEEG is useful in the presurgical evaluation of patients with nonlesional neocortical epilepsy. Concordant test results of either MSI or SISCOM with ICEEG provide useful additive information for that provided by ICEEG alone to localize the EZ in this most challenging group of patients. When sublobar concordance with ICEEG is observed, MSI is more advantageous compared to SISCOM in predicting seizure-free epilepsy surgery outcome.


Asunto(s)
Electroencefalografía/métodos , Epilepsia/diagnóstico por imagen , Epilepsia/patología , Imagen por Resonancia Magnética/métodos , Neocórtex/diagnóstico por imagen , Neocórtex/patología , Tomografía Computarizada de Emisión de Fotón Único/métodos , Adolescente , Adulto , Encéfalo/diagnóstico por imagen , Encéfalo/patología , Encéfalo/cirugía , Niño , Estudios de Cohortes , Femenino , Humanos , Magnetoencefalografía , Masculino , Persona de Mediana Edad , Neuroimagen/métodos , Procedimientos Neuroquirúrgicos , Oportunidad Relativa , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
13.
Epilepsia ; 54(12): 2195-2203, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24116733

RESUMEN

PURPOSE: The orbitofrontal (OF) region is one of the least explored regions of the cerebral cortex. There are few studies on patients with electrophysiologically and surgically confirmed OF epilepsy and a negative magnetic resonance imaging (MRI) study. We aimed to examine the neuroimaging characteristics of MRI-negative OF epilepsy with the focus on a voxel-based morphometric MRI postprocessing technique. METHODS: We included six patients with OF epilepsy, who met the following criteria: surgical resection of the OF lobe with/without adjacent cortex, seizure-free for ≥12 months, invasive video-electroencephalography (EEG) monitoring showing ictal onset from the OF area, and preoperative MRI regarded as negative. Patients were investigated in terms of their image postprocessing and functional neuroimaging characteristics, electroclinical characteristics obtained from noninvasive and invasive evaluations, and surgical pathology. MRI postprocessing on T1 -weighted high-resolution scans was implemented with a morphometric analysis program (MAP) in MATLAB. KEY FINDINGS: Single MAP+ abnormalities were found in four patients; three were in the OF region and one in the ipsilateral mesial frontal area. These abnormalities were included in the resection. One patient had bilateral MAP+ abnormalities in the OF region, with the ipsilateral one completely removed. The MAP+ foci were concordant with invasive electrophysiologic data in the majority of MAP+ patients (four of five). The localization value of 18F-fluorodeoxyglucose-positron emission tomography (FDG-PET) and ictal single-photon emission computed tomography (SPECT) is low in this cohort. Surgical pathology included focal cortical dysplasia, remote infarct, Rosenthal fiber formation and gliosis. SIGNIFICANCE: Our study highlights the importance of MRI postprocessing in the process of presurgical evaluation of patients with suspected orbitofrontal epilepsy and "normal" MRI. Using MAP, we were able to positively identify subtle focal abnormalities in the majority of the patients. MAP results need to be interpreted in the context of their electroclinical findings and can provide valuable targets in the process of planning invasive evaluation.


Asunto(s)
Epilepsia del Lóbulo Frontal/patología , Imagen por Resonancia Magnética , Neuroimagen , Adolescente , Adulto , Proteínas Bacterianas , Encéfalo/patología , Encéfalo/fisiopatología , Niño , Electroencefalografía , Epilepsia del Lóbulo Frontal/fisiopatología , Exotoxinas , Femenino , Neuroimagen Funcional , Humanos , Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Neuroimagen/métodos , Tomografía de Emisión de Positrones , Adulto Joven
14.
Brain Res Bull ; 192: 21-35, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36336143

RESUMEN

Directed outgrowth of axons is fundamental for the establishment of neuronal networks. Axon outgrowth is guided by growth cones, highly motile structures enriched in filamentous actin (F-actin) located at the axons' distal tips. Growth cones exploit F-actin-based protrusions to scan the environment for guidance cues, and they contain the sensory apparatus to translate guidance cue information into intracellular signaling cascades. These cascades act upstream of actin-binding proteins (ABP) and thereby control assembly and disassembly of F-actin. Spatiotemporally controlled F-actin dis-/assembly in growth cones steers the axon towards attractants and away from repellents, and it thereby navigates the axon through the developing nervous system. Hence, ABP that control F-actin dynamics emerged as critical regulators of neuronal network formation. In the present review article, we will summarize and discuss current knowledge of the mechanisms that control remodeling of the actin cytoskeleton in growth cones, focusing on recent progress in the field. Further, we will introduce tools and techniques that allow to study actin regulatory mechanism in growth cones.


Asunto(s)
Actinas , Conos de Crecimiento , Conos de Crecimiento/metabolismo , Actinas/metabolismo , Citoesqueleto de Actina/metabolismo , Axones/metabolismo , Proteínas de Microfilamentos/metabolismo
15.
Sci Rep ; 13(1): 3897, 2023 Mar 08.
Artículo en Inglés | MEDLINE | ID: mdl-36890210

RESUMEN

We have grown [Formula: see text]Th:CaF[Formula: see text] and [Formula: see text]Th:CaF[Formula: see text] single crystals for investigations on the VUV laser-accessible first nuclear excited state of [Formula: see text]Th, with the aim of building a solid-state nuclear clock. To reach high doping concentrations despite the extreme scarcity (and radioactivity) of [Formula: see text]Th, we have scaled down the crystal volume by a factor 100 compared to established commercial or scientific growth processes. We use the vertical gradient freeze method on 3.2 mm diameter seed single crystals with a 2 mm drilled pocket, filled with a co-precipitated CaF[Formula: see text]:ThF[Formula: see text]:PbF[Formula: see text] powder in order to grow single crystals. Concentrations of [Formula: see text] cm[Formula: see text] have been realized with [Formula: see text]Th with good (> 10%) VUV transmission. However, the intrinsic radioactivity of [Formula: see text]Th drives radio-induced dissociation during growth and radiation damage after solidification. Both lead to a degradation of VUV transmission, currently limiting the [Formula: see text]Th concentration to [Formula: see text] cm[Formula: see text].

16.
Cancers (Basel) ; 15(20)2023 Oct 19.
Artículo en Inglés | MEDLINE | ID: mdl-37894418

RESUMEN

Clear cell renal cell carcinoma (ccRCC) is characterized by a high degree of intratumoral heterogeneity (ITH). Besides genomic ITH, there is considerable functional ITH, which encompasses spatial niches with distinct proliferative and signaling activities. The full extent of functional spatial heterogeneity in ccRCC is incompletely understood. In the present study, a total of 17 ccRCC tissue specimens from different sites (primary tumor, n = 11; local recurrence, n = 1; distant metastasis, n = 5) were analyzed using digital spatial profiling (DSP) of protein expression. A total of 128 regions of interest from the tumor periphery and tumor center were analyzed for the expression of 46 proteins, comprising three major signaling pathways as well as immune cell markers. Results were correlated to clinico-pathological variables. The differential expression of granzyme B was validated using conventional immunohistochemistry and was correlated to the cancer-specific patient survival. We found that a total of 37 proteins were differentially expressed between the tumor periphery and tumor center. Thirty-five of the proteins were upregulated in the tumor periphery compared to the center. These included proteins involved in cell proliferation, MAPK and PI3K/AKT signaling, apoptosis regulation, epithelial-to-mesenchymal transition, as well as immune cell markers. Among the most significantly upregulated proteins in the tumor periphery was granzyme B. Granzyme B upregulation in the tumor periphery correlated with a significantly reduced cancer-specific patient survival. In conclusion, this study highlights the unique cellular contexture of the tumor periphery in ccRCC. The correlation between granzyme B upregulation in the tumor periphery and patient survival suggests local selection pressure for aggressive tumor growth and disease progression. Our results underscore the potential of spatial biology for biomarker discovery in ccRCC and cancer in general.

17.
Epilepsia ; 53(8): 1379-86, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22686598

RESUMEN

PURPOSE: The long-term seizure outcome of juvenile myoclonic epilepsy (JME) is still controversial; the value of factors that are potentially predictive for seizure outcome remains unclear. The aim of this study was both to investigate the long-term seizure outcome in patients with JME after a follow-up of at least 25 years and to identify factors that are predictive for the seizure outcome. METHODS: Data from 31 patients (19 women) with JME were studied. All of them had a follow-up of at least 25 years (mean 39.1 years) and were reevaluated with a review of their medical records and direct telephone or face-to-face interview. KEY FINDINGS: Of 31 patients 21 (67.7%) became seizure-free; in six of them (28.6%) antiepileptic drug (AED) treatment was discontinued due to seizure freedom. The occurrence of generalized tonic-clonic seizures (GTCS) preceded by bilateral myoclonic seizures (BMS) (p = 0.03), a long duration of epilepsy with unsuccessful treatment (p = 0.022), and AED polytherapy (p = 0.023) were identified as significant predictors for a poor long-term seizure outcome, whereas complete remission of GTCS under AED significantly increased the chance for complete seizure freedom (p = 0.012). The occurrence of photoparoxysmal responses significantly increases the risk of seizure recurrence after AED discontinuation (p = 0.05). SIGNIFICANCE: This study shows conclusively that JME is a heterogeneous epilepsy syndrome. Life-long AED treatment is not necessarily required to maintain seizure freedom. Several long-term outcome predictors that can potentially increase the ability of clinicians and their confidence to recommend different treatment options to patients with JME were identified.


Asunto(s)
Epilepsia Mioclónica Juvenil/diagnóstico , Adulto , Factores de Edad , Anciano , Anticonvulsivantes/uso terapéutico , Electroencefalografía , Epilepsia Tónico-Clónica/diagnóstico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Epilepsia Mioclónica Juvenil/tratamiento farmacológico , Epilepsia Mioclónica Juvenil/fisiopatología , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Convulsiones/diagnóstico , Convulsiones/tratamiento farmacológico
18.
Epilepsy Behav ; 24(2): 234-40, 2012 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-22542998

RESUMEN

OBJECTIVE: To investigate the utility of magnetic source imaging (MSI) for localizing the epileptogenic zone (EZ) and predicting epilepsy surgery outcome in non-lesional neocortical focal epilepsy (NLNE) patients. METHODS: Data from 18 consecutive patients with NLNE who underwent presurgical evaluation including intracranial electroencephalography (ICEEG) and MSI were studied. Follow-up after epilepsy surgery was ≥24 months. Intracranial electroencephalography and MSI results were classified using a sublobar classification. RESULTS: Sublobar ICEEG focus was completely resected in 15 patients; seizure-free rate was 60%. Eight patients showed sublobar-concordant ICEEG/MSI results and complete resection of both regions; seizure-free rate was 87.5%. Seizure-free rate in cases not matching these criteria was only 30% (p=0.013). CONCLUSIONS: Magnetoencephalography is a useful tool to localize the EZ and determine the site of surgical resection in NLNE patients. When sublobar concordance with ICEEG is observed, MSI increases the predictive value for a seizure-free epilepsy surgery outcome in these patients.


Asunto(s)
Electroencefalografía/métodos , Epilepsias Parciales/fisiopatología , Imagen por Resonancia Magnética/métodos , Magnetoencefalografía/métodos , Neocórtex/fisiopatología , Neuroimagen/métodos , Adolescente , Adulto , Niño , Estudios de Cohortes , Epilepsias Parciales/cirugía , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neocórtex/cirugía , Procedimientos Neuroquirúrgicos , Valor Predictivo de las Pruebas , Resultado del Tratamiento , Adulto Joven
19.
Pharmaceutics ; 14(5)2022 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-35631635

RESUMEN

In recent years, the colon has become a hot topic in biopharmaceutical research as several in vitro models of the human colon have been presented. A major focus is on the characterization of the microbiota and its capabilities. The aim of the present study was to further develop the MimiCol, preserving its properties and accelerating data acquisition. Emphasis was placed on the simplicity of its design and easy scalability. To prove the viability of the concept, degradation of sulfasalazine was investigated, and the bacterial composition during the experiment was assessed by 16S rRNA sequencing. The transfer of the experimental conditions to the new model was successful. Commercially available components were implemented in the setup. The model MimiCol3 represented the colon ascendens satisfactorily in its properties regarding volume, pH value, and redox potential. 16S rRNA sequencing led to further insights into the bacterial composition in the vessels. Degradation of sulfasalazine was in good agreement with in vivo data. The new model of the colon ascendens MimiCol3 enabled us to collect more reliable data, as three experiments were conducted simultaneously under the same conditions.

20.
Front Oncol ; 12: 889686, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35619925

RESUMEN

Renal cell carcinoma (RCC) is among the most lethal urological malignancies once metastatic. The introduction of immune checkpoint inhibitors has revolutionized the therapeutic landscape of metastatic RCC, nevertheless, a significant proportion of patients will experience disease progression. Novel treatment options are therefore still needed and in vitro and in vivo model systems are crucial to ultimately improve disease control. At the same time, RCC is characterized by a number of molecular and functional peculiarities that have the potential to limit the utility of pre-clinical model systems. This includes not only the well-known genomic intratumoral heterogeneity (ITH) of RCC but also a remarkable functional ITH that can be shaped by influences of the tumor microenvironment. Importantly, RCC is among the tumor entities, in which a high number of intratumoral cytotoxic T cells is associated with a poor prognosis. In fact, many of these T cells are exhausted, which represents a major challenge for modeling tumor-immune cell interactions. Lastly, pre-clinical drug development commonly relies on using phenotypic screening of 2D or 3D RCC cell culture models, however, the problem of "reverse engineering" can prevent the identification of the precise mode of action of drug candidates thus impeding their translation to the clinic. In conclusion, a holistic approach to model the complex "ecosystem RCC" will likely require not only a combination of model systems but also an integration of concepts and methods using artificial intelligence to further improve pre-clinical drug discovery.

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