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1.
J Bone Miner Metab ; 38(5): 639-647, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32303916

RESUMEN

INTRODUCTION: Collagen from marine esponges has been used as a promising material for tissue engineering proposals. Similarly, photobiomodulation (PBM) is able of modulating inflammatory processes after an injury, accelerating soft and hard tissue healing and stimulating neoangiogenesis. However, the effects of the associated treatments on bone tissue healing have not been studied yet. In this context, the present study aimed to evaluate the biological temporal modifications (using two experimental periods) of marine sponge collagen or sponging (SPG) based scaffold and PBM on newly formed bone using a calvaria bone defect model. MATERIAL AND METHODS: Wistar rats were distributed into two groups: SPG or SPG/PBM and euthanized into two different experimental periods (15 and 45 days post-surgery). A cranial critical bone defect was used to evaluate the effects of the treatments. Histology, histomorfometry and immunohistological analysis were performed. RESULTS: Histological findings demonstrated that SPG/PBM-treated animals, 45 days post-surgery, demonstrated a higher amount of connective and newly formed bone tissue at the region of the defect compared to CG. Notwithstanding, no difference among groups were observed in the histomorphometry. Interestingly, for both anti-transforming growth factor-beta (TGF-ß) and anti-vascular endothelial growth factor (VEGF) immunostaining, higher values for SPG/PBM, at 45 days post-surgery could be observed. CONCLUSION: It can be concluded that the associated treatment can be considered as a promising therapeutical intervention.


Asunto(s)
Organismos Acuáticos/química , Colágeno/farmacología , Terapia por Luz de Baja Intensidad , Cráneo/patología , Andamios del Tejido/química , Cicatrización de Heridas/efectos de los fármacos , Animales , Modelos Animales de Enfermedad , Masculino , Ratas Wistar , Cráneo/efectos de los fármacos , Factor de Crecimiento Transformador beta/metabolismo , Factor A de Crecimiento Endotelial Vascular/metabolismo
2.
J Mater Sci Mater Med ; 30(6): 64, 2019 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-31127392

RESUMEN

The combination of different biomaterials can be a promising intervention for the composites manufacture, mainly by adding functional and structural characteristics of each material and guarantee the advantages of the use of these composites. In this context, the aim of this study was to develop and evaluated the influence of the incorporation of marine spongin (SPG) into Biosilicate® (BS) in different proportions be used during bone repair. For this purpose, it was to develop and investigate different BS/SPG formulations for physico-chemical and morphological characteristics by pH, loss mass, Fourier transform infrared spectrometer (FTIR) and scanning electron microscope (SEM) analysis. Additionally, the influence of these composites on cell viability, proliferation, and alkaline phosphatase (ALP) activity were investigated. The results revealed that the pH values of all BS groups (with or without SPG) increased over time. A significant mass loss was observed in all composites, mainly with higher SPG percentages. Additionaly, SEM micrographies demonstrated fibers of SPG into BS and material degradation over time. Moreover, FTIR spectral analysis revealed characteristic peaks of PMMA, BS, and SPG in BS/SPG composites. BS/SPG groups demonstrated a positive effect for fibroblast proliferation after 3 and 7 days of culture. Additionally, BS and BS/SPG formulations (at 10% and 20% of SPG) presented similar values of osteoblasts viability and proliferation after 7 days of culture. Furthermore, ALP activity demonstrated no significant difference between BS and BS/SPG scaffolds, at any composition. Based on the present in vitro results, it can be concluded that the incorporation of SPG into BS was possible and produced an improvement in the physical-chemical characteristics and in the biological performance of the graft especially the formulation with 80/20 and 90/10. Future research should focus on in vivo evaluations of this novel composite.


Asunto(s)
Materiales Biocompatibles/química , Vidrio/química , Poríferos/metabolismo , Células 3T3 , Fosfatasa Alcalina/metabolismo , Animales , Sustitutos de Huesos/química , Línea Celular , Proliferación Celular , Supervivencia Celular , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Ratones , Microscopía Electrónica de Rastreo , Osteoblastos/metabolismo , Espectroscopía Infrarroja por Transformada de Fourier , Ingeniería de Tejidos/métodos , Andamios del Tejido
3.
Neuropathol Appl Neurobiol ; 43(3): 200-214, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27859539

RESUMEN

AIM: The p.P301L mutation in microtubule-associated protein tau (MAPT) is a common cause of frontotemporal dementia and parkinsonism linked to chromosome 17 (FTDP-17). We compare clinicopathologic features of five unrelated and three related (brother, sister and cousin) patients with FTDP-17 due to p.P301L mutation. METHODS: Genealogical, clinical, neuropathologic and genetic data were reviewed from eight individuals. RESULTS: The series consisted of five men and three women with an average age of death of 58 years (52-65 years) and average disease duration of 9 years (3-14 years). The first symptoms were those of behavioural variant frontotemporal dementia in seven patients and semantic variant of primary progressive aphasia in one. Three patients were homozygous for the MAPT H1 haplotype; five had H1/H2 genotype. The apolipoprotein E genotype was ϵ3/ϵ3 in seven and ϵ3/ϵ4 in one. The average brain weight was 1015 g (876-1188 g). All had frontotemporal lobar or more diffuse cortical atrophy. Except for one patient, the hippocampus and parahippocampal gyrus had minimal atrophy, whereas there was atrophy of middle and inferior temporal gyri. Dentate fascia neuronal dispersion was identified in three patients, two of whom had epilepsy. In one patient there was extensive white matter tau involvement with Gallyas-positive globular glial inclusions typical of globular glial tauopathy (GGT). CONCLUSIONS: This clinicopathologic study shows inter- and intra-familial clinicopathologic heterogeneity of FTDP-17 due to MAPT p.P301L mutation, including GGT in one patient.


Asunto(s)
Demencia Frontotemporal/genética , Demencia Frontotemporal/patología , Tauopatías/genética , Proteínas tau/genética , Anciano , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Mutación , Neuroglía/patología , Linaje
4.
Mult Scler ; 22(5): 698-704, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26447065

RESUMEN

BACKGROUND AND OBJECTIVES: We report a comprehensive clinical, radiological, neuropsychometric and pathological evaluation of a woman with a clinical diagnosis of AD dementia (ADem), but whose autopsy demonstrated widespread demyelination, without Alzheimer disease (AD) pathology. METHODS AND RESULTS: Initial neuropsychometric evaluation suggested amnestic mild cognitive impairment (aMCI). Serial magnetic resonance images (MRI) images demonstrated the rate of increase in her ventricular volume was comparable to that of 46 subjects with aMCI who progressed to ADem, without accumulating white matter disease. Myelin immunohistochemistry at autopsy demonstrated extensive cortical subpial demyelination. Subpial lesions involved the upper cortical layers, and often extended through the entire width of the cortex. CONCLUSIONS: Multiple sclerosis (MS) can cause severe cortical dysfunction and mimic ADem. Cortical demyelination is not well detected by standard imaging modalities and may not be detected on autopsy without myelin immunohistochemistry.


Asunto(s)
Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/patología , Corteza Cerebral/diagnóstico por imagen , Corteza Cerebral/patología , Esclerosis Múltiple/diagnóstico por imagen , Esclerosis Múltiple/patología , Autopsia , Humanos , Imagen por Resonancia Magnética/métodos , Vaina de Mielina/patología
5.
Eur J Neurol ; 22(9): 1323-5, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26278106

RESUMEN

BACKGROUND: Recently, a novel mutation in exon 24 of DNAJC13 gene (p.Asn855Ser, rs387907571) has been reported to cause autosomal dominant Parkinson's disease (PD) in a multi-incident Mennonite family. METHODS: In the present study the mutation containing exon of the DNAJC13 gene has been sequenced in a Caucasian series consisting of 1938 patients with clinical PD and 838 with pathologically diagnosed Lewy body disease (LBD). RESULTS: Our sequence analysis did not identify any coding variants in exon 24 of DNAJC13. Two previously described variants in intron 23 (rs200204728 and rs2369796) were observed. CONCLUSION: Our results indicate that the region surrounding the DNAJC13 p.Asn855Ser substitution is highly conserved and mutations in this exon are not a common cause of PD or LBD among Caucasian populations.


Asunto(s)
Enfermedad por Cuerpos de Lewy/genética , Chaperonas Moleculares/genética , Enfermedad de Parkinson/genética , Adulto , Anciano , Anciano de 80 o más Años , Europa (Continente) , Exones , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mutación
6.
Clin Auton Res ; 25(1): 77-80, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25739472

RESUMEN

We used double immunocytochemistry for α-synuclein and markers of sympathoexcitatory neurons, oligodendrocytes, iron metabolism, and autophagy to study putative neuropathological interactions in multiple system atrophy. We focused in the rostral ventrolateral medulla as a prototype vulnerable region. We found that loss of C1 neurons and oligodendrocytes related to glial cytoplasmic inclusion accumulation, downregulation of iron transport, and upregulation of autophagy and ferritin expression in these area.


Asunto(s)
Tronco Encefálico/patología , Tronco Encefálico/fisiopatología , Atrofia de Múltiples Sistemas/patología , Atrofia de Múltiples Sistemas/fisiopatología , Anciano , Animales , Proteínas Reguladoras de la Apoptosis/metabolismo , Beclina-1 , Tronco Encefálico/metabolismo , Estudios de Casos y Controles , Proteínas de Transporte de Catión/metabolismo , Modelos Animales de Enfermedad , Humanos , Masculino , Proteínas de la Membrana/metabolismo , Ratones , Persona de Mediana Edad , Atrofia de Múltiples Sistemas/metabolismo , Neuroglía/metabolismo , Neuroglía/patología , Oligodendroglía/metabolismo , Oligodendroglía/patología , alfa-Sinucleína/metabolismo
7.
Phys Chem Chem Phys ; 16(3): 1067-77, 2014 Jan 21.
Artículo en Inglés | MEDLINE | ID: mdl-24288034

RESUMEN

Soluble molecular semiconductors are a promising alternative to semiconducting polymers in the field of organic photovoltaics. Here, three custom-made symmetric 1,3-bis(N,N-alkylated-2,6-dihydroxy-anilino)squaraines containing systematic variations in their molecular structures are compared regarding their applicability as donor materials in bulk-heterojunction solar cells. The terminal substitution pattern of the squaraines is varied from cyclic over linear to branched including a stereogenic center. Single crystal structures are determined, and, in the case of chiral squaraine, unusual formation of stereoisomer co-crystals is revealed. The thin film absorbance spectra show characteristic signatures of H- and J-bands or hint at the formation of tautomers. The general feasibility of these model compounds for photovoltaic applications is studied by light-induced electron spin resonance spectroscopy. The impact of the different molecular substitution patterns on aggregation behavior and, consequently, their optoelectronic solid state properties including charge carrier mobility and finally the solar cell performance are investigated.

8.
Rev Sci Instrum ; 95(3)2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38552175

RESUMEN

In light of the accumulation of characterization measurement data in the industrial production of solar cell devices, the investigation of a large amount of samples by statistical means lends itself to be a useful tool to gain further insights into how the data correlate with performance parameters. However, due to the multicollinearity among high-dimensional input parameters of compositional data, revealing the underlying patterns may prove to be a difficult endeavor. In this work, we present statistics consisting of 280 thin-film solar cell samples based on Cu(In, Ga)(S, Se)2 absorber layers whose depth-resolved composition was assessed by glow-discharge optical emission spectroscopy (GDOES). After parameterization of the features of [Ga]/([Ga] + [In])and[S]/([S] + [Se]) gradings, we employ two-way clustering in order to group samples and features by their similarity. In addition, using principal component analysis, information in the dataset, which is irrelevant to the problem, is removed by dimensionality reduction. In this way, it is possible to create a map that provides an overview of the GDOES data of all samples in their entirety, including correlations among features. More importantly, it also opens up a more precise way to plan further improvements in the compositional gradings by unveiling a path along which the experimenter can read the feature changes concerned with an improvement in the open-circuit voltage deficit or any other target parameter of interest. New samples can then be assigned to existing cluster centroids to predict what target parameter value they would assume.

9.
Eur J Neurol ; 20(10): 1417-22, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23746093

RESUMEN

BACKGROUND AND PURPOSE: Midbrain atrophy is a characteristic feature of progressive supranuclear palsy (PSP), although it is unclear whether it is associated with the PSP syndrome (PSPS) or PSP pathology. The aim of the present study was to determine whether midbrain atrophy is a useful biomarker of PSP pathology, or whether it is only associated with typical PSPS. METHODS: All autopsy-confirmed subjects were identified with the PSP clinical phenotype (i.e. PSPS) or PSP pathology and a volumetric MRI. Of 24 subjects with PSP pathology, 11 had a clinical diagnosis of PSPS (PSP-PSPS), and 13 had a non-PSPS clinical diagnosis (PSP-other). Three subjects had PSPS and corticobasal degeneration pathology (CBD-PSPS). Healthy control and disease control groups (i.e. a group without PSPS or PSP pathology) and a group with CBD pathology and corticobasal syndrome (CBD-CBS) were selected. The midbrain area was measured in all subjects. [Correction added on 21 June 2013, after first online publication: the abbreviation of corticobasal degeneration pathology was changed from CBD-PSP to CBD-PSPS.] RESULTS: The midbrain area was reduced in each group with clinical PSPS (with and without PSP pathology). The group with PSP pathology and non-PSPS clinical syndromes did not show reduced midbrain area. Midbrain area was smaller in the subjects with PSPS than in those without PSPS (P < 0.0001), with an area under the receiver operator curve of 0.99 (0.88, 0.99). A midbrain area cut-point of 92 mm(2) provided optimum sensitivity (93%) and specificity (89%) for differentiation. CONCLUSION: Midbrain atrophy is associated with the clinical presentation of PSPS, but not with the pathological diagnosis of PSP in the absence of clinical PSPS. This finding has important implications for the utility of midbrain measurements as diagnostic biomarkers for PSP pathology.


Asunto(s)
Mesencéfalo/patología , Parálisis Supranuclear Progresiva/patología , Anciano , Anciano de 80 o más Años , Atrofia , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Síndrome
10.
J Biomater Appl ; 37(9): 1632-1644, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36916869

RESUMEN

This study aimed to develop bone regenerative therapeutic strategies, based on the addition of bone marrow stromal cells (BMSC) on bioglass/collagen (BG/COL) scaffolds. For this purpose, an in vivo study was conducted using tissue response of the BG/COL scaffolds combined with BMSC in a critical-size defects. Wistar rats were submitted to the surgical procedure to perform the cranial critical size bone defects and distributed in four groups (20 animals per group): Control Group (CG) (rats submitted to the cranial bone defect surgery without treatment), Bioglass Group (BG) (rats treated with BG), BG/COL Group (rats treated with BG/COL) and Bioglass/Collagen and BMSC Group (BG/COL/BMSC) (rats treated with BG/COL scaffolds enriched with BMSCs). Animals were euthanized 15 and 30 days after surgery. Scanning electron microscopy, histopathological and immunohistochemistry analysis were used. SEM analysis demonstrated that porous scaffolds were obtained, and Col fibers were successfully impregnated to BG matrices. The implantation of the BMSC on BG/COL based scaffolds was effective in stimulating newly bone formation and produced an increased immunoexpression of markers related to the bone repair. These results highlight the potential of BG/COL scaffolds and BMSCs to be used as a therapeutic approach for bone regeneration.


Asunto(s)
Células Madre Mesenquimatosas , Andamios del Tejido , Ratas , Animales , Ratas Wistar , Colágeno/farmacología , Osteogénesis , Regeneración Ósea , Modelos Teóricos , Células de la Médula Ósea , Ingeniería de Tejidos/métodos
11.
Neuropathol Appl Neurobiol ; 38(2): 142-52, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21696423

RESUMEN

AIMS: Rapid eye movement sleep behaviour disorder (RBD) is characterized by loss of muscle atonia during rapid eye movement sleep and is associated with dream enactment behaviour. RBD is often associated with α-synuclein pathology, and we examined if there is a relationship of RBD with cholinergic neuronal loss in the pedunculopontine/laterodorsal tegmental nucleus (PPN/LDT), compared to catecholaminergic neurones in a neighbouring nucleus, the locus coeruleus (LC). METHODS: This retrospective study utilized human brain banked tissues of 11 Lewy body disease (LBD) cases with RBD, 10 LBD without RBD, 19 Alzheimer's disease (AD) and 10 neurologically normal controls. Tissues were stained with choline acetyl transferase immunohistochemistry to label neurones of PPN/LDT and tyrosine hydroxylase for the LC. The burden of tau and α-synuclein pathology was measured in the same regions with immunohistochemistry. RESULTS: Both the LC and PPN/LDT were vulnerable to α-synuclein pathology in LBD and tau pathology in AD, but significant neuronal loss was only detected in these nuclei in LBD. Greater cholinergic depletion was found in both LBD groups, regardless of RBD status, when compared with normals and AD. There were no differences in either degree of neuronal loss or burden of α-synuclein pathology in LBD with and without RBD. CONCLUSIONS: Whether decreases in brainstem cholinergic neurones in LBD contribute to RBD is uncertain, but our findings indicate these neurones are highly vulnerable to α-synuclein pathology in LBD and tau pathology in AD. The mechanism of selective α-synuclein-mediated neuronal loss in these nuclei remains to be determined.


Asunto(s)
Tronco Encefálico/patología , Catecolaminas/metabolismo , Colinérgicos/metabolismo , Trastorno de la Conducta del Sueño REM/metabolismo , Trastorno de la Conducta del Sueño REM/patología , Anciano , Anciano de 80 o más Años , Tronco Encefálico/metabolismo , Femenino , Humanos , Enfermedad por Cuerpos de Lewy/diagnóstico , Enfermedad por Cuerpos de Lewy/patología , Locus Coeruleus/metabolismo , Masculino , Enfermedades del Sistema Nervioso/diagnóstico , Enfermedades del Sistema Nervioso/metabolismo , Neuronas/metabolismo , Neuronas/patología , Trastorno de la Conducta del Sueño REM/diagnóstico , Estudios Retrospectivos , alfa-Sinucleína/metabolismo
12.
Eur J Neurol ; 17(7): 969-75, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20236174

RESUMEN

BACKGROUND AND PURPOSE: Frontotemporal lobar degeneration (FTLD) can be subdivided into those in which the abnormal protein is tau (FTLD-TAU), the TAR DNA binding protein 43 (FTLD-TDP) and the fused in sarcoma protein (FTLD-FUS). We have observed severe caudate atrophy at autopsy in FTLD-FUS, and hence, we aimed to determine whether caudate atrophy on MRI is a feature that can distinguish FTLD-FUS from FTLD-TDP and FTLD-TAU. METHODS: From a cohort of 207 cases of FTLD, we identified all cases of FTLD-FUS that had a volumetric antemortem head MRI (n = 3). Caudate and frontal lobe volumes were measured in all three cases using atlas-based parcellation and SPM5 and were compared to 10 randomly selected cases of FTLD-TDP and 10 randomly selected cases of FTLD-TAU. Total grey matter volumes were also calculated for all cases. RESULTS: The FTLD-FUS cases had significantly smaller caudate volumes (P = 0.02) yet similar frontal lobe grey matter volumes (P = 0.12) compared to FTLD-TDP and FTLD-TAU. Caudate volumes when corrected for total grey matter volume (P = 0.01) or frontal lobe grey matter volume (P = 0.01) were significantly smaller in FTLD-FUS than in FTLD-TDP and FTLD-TAU and showed no overlap with the other two groups. CONCLUSIONS: Caudate atrophy on MRI appears to be significantly greater in FTLD-FUS compared with FTLD-TDP and FTLD-TAU, suggesting that severe caudate atrophy may be a useful clinical feature to predict FTLD-FUS pathology.


Asunto(s)
Núcleo Caudado/patología , Proteínas de Unión al ADN/metabolismo , Lóbulo Frontal/patología , Demencia Frontotemporal/diagnóstico , Demencia Frontotemporal/patología , Proteína FUS de Unión a ARN/metabolismo , Anciano , Atrofia , Biomarcadores/metabolismo , Mapeo Encefálico/métodos , Núcleo Caudado/metabolismo , Estudios de Cohortes , Diagnóstico Diferencial , Femenino , Lóbulo Frontal/metabolismo , Demencia Frontotemporal/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Índice de Severidad de la Enfermedad , Proteínas tau/metabolismo
13.
J Phys Chem A ; 114(11): 3981-9, 2010 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-20030383

RESUMEN

The addition of small amounts of dodecylamine-capped Au nanoparticles into the active layer of organic bulk heterojunction solar cells consisting of poly(3-octylthiophene) (P3OT) and C(60) was recently suggested to have a positive impact on device performance due to improved electron transport. This issue was systematically further investigated in the present work. Different strategies to incorporate colloidally prepared Au nanoparticles with a narrow size distribution into organic solar cells with the more common donor/acceptor system consisting of poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl C(61)-butyric acid methyl ester (PCBM) were pursued. Au nanoparticles were prepared with either P3HT or dodecylamine as ligands. Additionally, efforts were undertaken to incorporate nearly ligand-free Au nanoparticles into the system. Therefore, a procedure was successfully developed to remove the dodecylamine ligand shell by a postpreparative ligand exchange with pyridine, a much smaller molecule that can later partly be removed from solid films by annealing. However, for all types of nanoparticles studied here, the performance of the P3HT/PCBM solar cells was found to decrease with the Au particles as an additive to the active layer, meaning that adding Au nanoparticles is not a suitable strategy in the case of the P3HT/PCBM system. Possible reasons are discussed on the basis of detailed investigations of the structure, photophysics and charge transport in the system.

14.
Brain ; 131(Pt 7): 1759-75, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18535080

RESUMEN

Atypical imaging features of multiple sclerosis lesions include size >2 cm, mass effect, oedema and/or ring enhancement. This constellation is often referred to as 'tumefactive multiple sclerosis'. Previous series emphasize their unifocal and clinically isolated nature, however, evolution of these lesions is not well defined. Biopsy may be required for diagnosis. We describe clinical and radiographic features in 168 patients with biopsy confirmed CNS inflammatory demyelinating disease (IDD). Lesions were analysed on pre- and post-biopsy magnetic resonance imaging (MRI) for location, size, mass effect/oedema, enhancement, multifocality and fulfilment of Barkhof criteria. Clinical data were correlated to MRI. Female to male ratio was 1.2 : 1, median age at onset, 37 years, duration between symptom onset and biopsy, 7.1 weeks and total disease duration, 3.9 years. Clinical course prior to biopsy was a first neurological event in 61%, relapsing-remitting in 29% and progressive in 4%. Presentations were typically polysymptomatic, with motor, cognitive and sensory symptoms predominating. Aphasia, agnosia, seizures and visual field defects were observed. At follow-up, 70% developed definite multiple sclerosis, and 14% had an isolated demyelinating syndrome. Median time to second attack was 4.8 years, and median EDSS at follow-up was 3.0. Multiple lesions were present in 70% on pre-biopsy MRI, and in 83% by last MRI, with Barkhof criteria fulfilled in 46% prior to biopsy and 55% by follow-up. Only 17% of cases remained unifocal. Median largest lesion size on T2-weighted images was 4 cm (range 0.5-12), with a discernible size of 2.1 cm (range 0.5-7.5). Biopsied lesions demonstrated mass effect in 45% and oedema in 77%. A strong association was found between lesion size, and presence of mass effect and/or oedema (P < 0.001). Ring enhancement was frequent. Most tumefactive features did not correlate with gender, course or diagnosis. Although lesion size >5 cm was associated with a slightly higher EDSS at last follow-up, long-term prognosis in patients with disease duration >10 years was better (EDSS 1.5) compared with a population-based multiple sclerosis cohort matched for disease duration (EDSS 3.5; P < 0.001). Given the retrospective nature of the study, the precise reason for biopsy could not always be determined. This study underscores the diagnostically challenging nature of CNS IDDs that present with atypical clinical or radiographic features. Most have multifocal disease at onset, and develop RRMS by follow-up. Although increased awareness of this broad spectrum may obviate need for biopsy in many circumstances, an important role for diagnostic brain biopsy may be required in some cases.


Asunto(s)
Esclerosis Múltiple/diagnóstico , Adolescente , Adulto , Anciano , Biopsia , Encéfalo/patología , Edema Encefálico/etiología , Edema Encefálico/patología , Niño , Progresión de la Enfermedad , Métodos Epidemiológicos , Femenino , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Persona de Mediana Edad , Esclerosis Múltiple/complicaciones , Esclerosis Múltiple/patología
15.
J Phys Condens Matter ; 21(26): 264015, 2009 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-21828463

RESUMEN

We studied the formation of tree-like patterns of polymer aggregates and rings of nanoparticles during evaporation from a fluid film. We utilize phase separation between two immiscible fluids to generate a double-layer film which dries up in a sequential manner. Both fluid layers may contain a solute, polymer aggregates or nanoparticles. During evaporation of the top layer, instabilities may occur and direct a self-assembly process of the solute which may be further affected by an instability of the bottom layer at a later stage. We present two cases where, after evaporation of the top fluid layer, the solute was adsorbed on the surface of the bottom fluid layer. In comparison to dewetting of a single fluid layer on a solid substrate, the advantage of our double-layer approach lies in the deposition of the solute on the surface of the bottom fluid layer. The relatively high mobility of the solute on such a fluid surface favors the formation of ordered patterns, driven by an instability of the bottom layer.

16.
Mar Biotechnol (NY) ; 21(1): 30-37, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30218326

RESUMEN

Biomaterial-based bone grafts have an important role in the field of bone tissue engineering. One of the most promising classes of biomaterials is collagen, including the ones from marine biodiversity (in general, called spongin (SPG)). Also, hydroxyapatite (HA) has an important role in stimulating bone metabolism. Therefore, this work investigated the association of HA and SPG composites in order to evaluate their physico-chemical and morphological characteristics and their in vitro biological performance. For this, pre-set composite disks were evaluated by means of mass loss after incubation, pH, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and "in vitro" cell viability. pH measurements showed no statistical difference between groups. Moreover, a higher mass loss was observed for HA/SPG70/30 compared to the other groups for all experimental periods. Moreover, SEM representative micrographs showed the degradation of the samples with and without immersion. FTIR analysis demonstrated the absorption peaks for poly(methyl methacrylate) (PMMA), HA, and SPG. A higher L292 cell viability for control and PMMA was observed compared to HA and HA/SPG 90/10. Also, HA/SPG 70/30 showed higher cell viability compared to HA and HA/SPG 90/10 on days 3 and 7 days of culture. Furthermore, HA showed a significant lower MC3T3 cell viability compared to control and HA/SPG 70/30 on day 3 and no significant difference was observed between the composites in the last experimental period. Based on our investigations, it can be concluded that the mentioned composites were successfully obtained, presenting improved biological properties, especially the one mimicking the composition of bone (with 70% of HA and 30% of SPG). Consequently, these data highlight the potential of the introduction of SPG into HA to improve the performance of the graft for bone regeneration applications. Further long-term studies should be carried out to provide additional information concerning the late stages of material degradation and bone healing in the presence of HA/SPG.


Asunto(s)
Materiales Biocompatibles/química , Sustitutos de Huesos/química , Colágeno/química , Durapatita/química , Polimetil Metacrilato/química , Andamios del Tejido , Animales , Materiales Biocompatibles/farmacología , Sustitutos de Huesos/farmacología , Huesos/citología , Línea Celular , Supervivencia Celular/efectos de los fármacos , Colágeno/farmacología , Durapatita/farmacología , Fibroblastos/citología , Fibroblastos/efectos de los fármacos , Concentración de Iones de Hidrógeno , Ratones , Células 3T3 NIH , Polimetil Metacrilato/farmacología , Poríferos/química , Ingeniería de Tejidos/métodos
17.
Neuron ; 16(1): 77-87, 1996 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8562093

RESUMEN

Periventricular heterotopia (PH) involves dramatic malformations of the human cerebral cortex. Here we show that PH is closely linked to markers in distal Xq28 (maximal two-point lod score = 4.77 for F8C at theta = 0; maximal multipoint lod score = 5.37), so that affected females are obligatory mosaics for the mutation; that PH is lethal to at least some affected males; that PH malformations consist of well-differentiated cortical neurons filling the adult subependymal zone; and that individuals with PH are at high risk for epilepsy, though they have no other neurological or external stigmata. The PH gene may represent an important epilepsy susceptibility locus in addition to playing a key role in normal cortical development.


Asunto(s)
Encefalopatías/genética , Corteza Cerebral , Coristoma/genética , Epilepsia/genética , Cromosoma X , Aborto Habitual/genética , Adulto , Encefalopatías/patología , Coristoma/patología , Epilepsia/patología , Epilepsia Generalizada/genética , Epilepsia Generalizada/patología , Epilepsia del Lóbulo Temporal/genética , Epilepsia del Lóbulo Temporal/patología , Femenino , Muerte Fetal/genética , Genes Dominantes , Genes Letales , Humanos , Recién Nacido , Escala de Lod , Imagen por Resonancia Magnética , Masculino , Linaje , Embarazo
18.
Brain ; 130(Pt 11): 2770-88, 2007 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-17412731

RESUMEN

REM sleep behaviour disorder (RBD) is a parasomnia characterized by the loss of normal skeletal muscle atonia during REM sleep with prominent motor activity accompanying dreaming. The terminology relating to RBD, and mechanisms underlying REM sleep without atonia and RBD based on data in cat and rat are presented. Neuroimaging data from the few published human cases with RBD associated with structural lesions in the brainstem are presented, in which the dorsal midbrain and pons are implicated. Pharmacological manipulations which alter RBD frequency and severity are reviewed, and the data from human neuropathological studies are presented. An anatomic framework and new schema for the pathophysiology of RBD are proposed based on recent data in rat regarding the putative flip-flop switch for REM sleep control. The structure in man analogous to the subcoeruleus region in cat and sublaterodorsal nucleus in rat is proposed as the nucleus (and its associated efferent and afferent pathways) crucial to RBD pathophysiology. The association of RBD with neurological disease ('secondary RBD') is presented, with emphasis on RBD associated with neurodegenerative disease, particularly the synucleinopathies. The hypothesized pathophysiology of RBD is presented in relation to the Braak staging system for Parkinson's disease, in which the topography and temporal sequence of synuclein pathology in the brain could explain the evolution of parkinsonism and/or dementia well after the onset of RBD. These data suggest that many patients with 'idiopathic' RBD are actually exhibiting an early clinical manifestation of an evolving neurodegenerative disorder. Such patients may be appropriate for future drug therapies that affect synuclein pathophysiology, in which the development of parkinsonism and/or dementia could be delayed or prevented. We suggest that additional clinicopathological studies be performed in patients with dementia or parkinsonism, with and without RBD, as well as in patients with idiopathic RBD, to further elucidate the pathophysiology and also characterize the clinical and pathophysiological relevance of RBD in neurodegenerative disease. Furthermore, longitudinal studies in patients with idiopathic RBD are warranted to characterize the natural history of such patients and prepare for future therapeutic trials.


Asunto(s)
Encéfalo/fisiopatología , Trastorno de la Conducta del Sueño REM/fisiopatología , Animales , Encéfalo/patología , Humanos , Imagen por Resonancia Magnética , Modelos Animales , Enfermedades Neurodegenerativas/patología , Enfermedades Neurodegenerativas/fisiopatología , Trastorno de la Conducta del Sueño REM/patología
19.
Endocr Pathol ; 19(2): 112-6, 2008.
Artículo en Inglés | MEDLINE | ID: mdl-18496772

RESUMEN

The normal infundibulum and neurohypophysis consist entirely of neuronal processes, the neuronal cell bodies of which lie within the supraoptic and paraventricular nuclei of the hypothalamus and supportive glial cells or pituicytes. The finding of neurons within the neurohypophysis is exceedingly rare, as are ganglion cell tumors at this site. In this paper, we report a ganglion cell tumor of the neurohypophysis found incidentally at autopsy. Despite chronic hypertension and the finding of some vasopressin immunoreactivity in lesional neurons, the syndrome of inappropriate antidiuretic hormone secretion (SIADH) was excluded on the basis of normal serum sodium levels. The morphologic and immunohistochemical features of the tumor are presented, cytogenetic considerations are discussed, and literature regarding neuronal lesions of the pituitary gland is reviewed.


Asunto(s)
Ganglioglioma/patología , Neurohipófisis/patología , Neoplasias Hipofisarias/patología , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Encéfalo/patología , Femenino , Humanos , Inmunohistoquímica , Síndrome de Secreción Inadecuada de ADH/diagnóstico , Síndrome de Secreción Inadecuada de ADH/patología , Hipófisis/patología , Sodio/sangre
20.
J Clin Neurosci ; 53: 239-240, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29685413

RESUMEN

Tolosa Hunt syndrome (THS) is characterized by painful ophthalmoplegia secondary to idiopathic granulomatous inflammation of the cavernous sinus. The characteristic finding on MRI is an enhancing T1 isointense and T2 hypo- or hyperintense cavernous sinus mass lesion, which may result in focal narrowing of the ipsilateral internal carotid artery. Although the incidence is quite rare, it is a common diagnostic consideration in cases that present with multiple cranial neuropathies. However, the differential diagnosis for a unilateral cavernous sinus lesion in adults is broad and includes neoplastic, inflammatory (such as sarcoidosis and immunoglobulin G4-related disease [IgG4-RD]), infectious etiologies (such as syphilis and leprosy), as well as vascular lesions. We describe a patient presenting with neurologic symptoms referable to a persistent unilateral cavernous sinus MRI abnormality, initially thought to be consistent with Tolosa-Hunt syndrome, that was clinically but not radiographically responsive to steroids. Following reevaluation due to the presence of new symptoms, pathology revealed that the abnormality was most consistent with chordoma, a rare skull based tumor. In patients with a presumed diagnosis of Tolosa-Hunt syndrome, close clinical and radiographic follow-up is imperative, with early consideration for biopsy in patients that fail to respond to treatment both clinically and radiographically.


Asunto(s)
Seno Cavernoso/patología , Cordoma/diagnóstico , Cordoma/patología , Neoplasias de la Base del Cráneo/diagnóstico , Neoplasias de la Base del Cráneo/patología , Diagnóstico Diferencial , Femenino , Humanos , Imagen por Resonancia Magnética , Persona de Mediana Edad , Esteroides/uso terapéutico , Síndrome de Tolosa-Hunt/diagnóstico
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