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1.
Brain Inj ; 36(8): 939-947, 2022 07 03.
Artículo en Inglés | MEDLINE | ID: mdl-35904331

RESUMEN

This prospective multicenter study evaluated differences in concussion severity and functional outcome using glial and neuronal biomarkers glial Fibrillary Acidic (GFAP) and Ubiquitin C-terminal Hydrolase (UCH-L1) in children and youth involved in non-sport related trauma, organized sports, and recreational activities. Children and youth presenting to three Level 1 trauma centersfollowing blunt head trauma with a GCS 15 with a verified diagnosis of a concussion were enrolled within 6 hours of injury. Traumatic intracranial lesions on CT scan and functional outcome within 3 months of injury were evaluated. 131 children and youth with concussion were enrolled, 81 in the no sports group, 22 in the organized sports group and 28 in the recreational activities group. Median GFAP levels were 0.18, 0.07, and 0.39 ng/mL in the respective groups (p = 0.014). Median UCH-L1 levels were 0.18, 0.27, and 0.32 ng/mL respectively (p = 0.025). A CT scan of the head was performed in 110 (84%) patients. CT was positive in 5 (7%), 4 (27%), and 5 (20%) patients, respectively. The AUC for GFAP for detecting +CT was 0.84 (95%CI 0.75-0.93) and for UCH-L1 was 0.82 (95%CI 0.71-0.94). In those without CT lesions, elevations in UCH-L1 were significantly associated with unfavorable 3-month outcome. Concussions in the 3 groups were of similar severity and functional outcome. GFAP and UCH-L1 were both associated with severity of concussion and intracranial lesions, with the most elevated concentrations in recreational activities .


Asunto(s)
Conmoción Encefálica , Traumatismos Cerrados de la Cabeza , Adolescente , Biomarcadores , Conmoción Encefálica/diagnóstico por imagen , Niño , Proteína Ácida Fibrilar de la Glía , Humanos , Estudios Prospectivos
2.
J Med Primatol ; 49(4): 179-187, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32157703

RESUMEN

BACKGROUND: This study evaluated and compared cardiorespiratory and blood gas parameters, as well as sedation, analgesia and recovery of two protocols: ketamine (10 mg/kg) or dexmedetomidine (10 µg/kg), with midazolam (0.5 mg/kg) and butorphanol (0.3 mg/kg), IM (KBM and DBM, respectively) in brown howler monkeys (Alouatta guariba clamitans). MATERIAL AND METHODS: Twelve brown howler monkeys were selected in two groups and evaluated for cardiorespiratory parameters and sedation, from 5-30 minutes after latency. Blood gas and arterial lactate were taken at 5 and 30 minutes. In the end, time and quality of recovery were evaluated. RESULTS: The HR in DBM group was significantly lower at all times. The sedation score was higher in DBM. Recovery in DBM was faster. All animals had moderate hypoxaemia. CONCLUSION: Both protocols produce satisfactory anaesthesia and analgesia, but DBM provides deeper sedation with faster recovery. Oxygen supplementation is recommended in both due to hypoxaemia.


Asunto(s)
Alouatta/fisiología , Analgesia/veterinaria , Butorfanol/uso terapéutico , Dexmedetomidina/uso terapéutico , Ketamina/uso terapéutico , Midazolam/uso terapéutico , Vasectomía/veterinaria , Alouatta/cirugía , Analgesia/instrumentación , Combinación de Medicamentos , Vasectomía/instrumentación
3.
J Biol Chem ; 293(6): 1957-1975, 2018 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-29284679

RESUMEN

Alzheimer's disease (AD) is a disabling and highly prevalent neurodegenerative condition, for which there are no effective therapies. Soluble oligomers of the amyloid-ß peptide (AßOs) are thought to be proximal neurotoxins involved in early neuronal oxidative stress and synapse damage, ultimately leading to neurodegeneration and memory impairment in AD. The aim of the current study was to evaluate the neuroprotective potential of mesenchymal stem cells (MSCs) against the deleterious impact of AßOs on hippocampal neurons. To this end, we established transwell cocultures of rat hippocampal neurons and MSCs. We show that MSCs and MSC-derived extracellular vesicles protect neurons against AßO-induced oxidative stress and synapse damage, revealed by loss of pre- and postsynaptic markers. Protection by MSCs entails three complementary mechanisms: 1) internalization and degradation of AßOs; 2) release of extracellular vesicles containing active catalase; and 3) selective secretion of interleukin-6, interleukin-10, and vascular endothelial growth factor to the medium. Results support the notion that MSCs may represent a promising alternative for cell-based therapies in AD.


Asunto(s)
Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/metabolismo , Vesículas Extracelulares/metabolismo , Hipocampo/citología , Células Madre Mesenquimatosas/citología , Neuronas/metabolismo , Estrés Oxidativo , Sinapsis/metabolismo , Enfermedad de Alzheimer/genética , Péptidos beta-Amiloides/química , Animales , Células Cultivadas , Técnicas de Cocultivo , Vesículas Extracelulares/genética , Hipocampo/metabolismo , Humanos , Interleucina-10/metabolismo , Interleucina-6/metabolismo , Masculino , Células Madre Mesenquimatosas/metabolismo , Neuronas/citología , Ratas , Ratas Wistar , Factor A de Crecimiento Endotelial Vascular/metabolismo
4.
J Neurochem ; 150(2): 138-157, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31009074

RESUMEN

Parkinson's disease (PD) is characterized by selective death of dopaminergic neurons in the substantia nigra, degeneration of the nigrostriatal pathway, increases in glutamatergic synapses in the striatum and aggregation of α-synuclein. Evidence suggests that oligomeric species of α-synuclein (αSO) are the genuine neurotoxins of PD. Although several studies have supported the direct neurotoxic effects of αSO on neurons, their effects on astrocytes have not been directly addressed. Astrocytes are essential to several steps of synapse formation and function, including secretion of synaptogenic factors, control of synaptic elimination and stabilization, secretion of neural/glial modulators, and modulation of extracellular ions, and neurotransmitter levels in the synaptic cleft. Here, we show that αSO induced the astrocyte reactivity and enhanced the synaptogenic capacity of human and murine astrocytes by increasing the levels of the known synaptogenic molecule transforming growth factor beta 1 (TGF-ß1). Moreover, intracerebroventricular injection of αSO in mice increased the number of astrocytes, the density of excitatory synapses, and the levels of TGF-ß1 in the striatum of injected animals. Inhibition of TGF-ß1 signaling impaired the effect of the astrocyte-conditioned medium on glutamatergic synapse formation in vitro and on striatal synapse formation in vivo, whereas addition of TGF-ß1 protected mesencephalic neurons against synapse loss triggered by αSO. Together, our data suggest that αSO have important effects on astrocytic functions and describe TGF-ß1 as a new endogenous astrocyte-derived molecule involved in the increase in striatal glutamatergic synaptic density present in early stages of PD. OPEN SCIENCE BADGES: This article has received a badge for *Open Materials* because it provided all relevant information to reproduce the study in the manuscript. The complete Open Science Disclosure form for this article can be found at the end of the article. More information about the Open Practices badges can be found at https://cos.io/our-services/open-science-badges/. Cover Image for this issue: doi: 10.1111/jnc.14514.


Asunto(s)
Astrocitos/metabolismo , Trastornos Parkinsonianos/metabolismo , Sinapsis/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo , alfa-Sinucleína/metabolismo , Animales , Modelos Animales de Enfermedad , Humanos , Ratones , Neurogénesis/fisiología , Transducción de Señal/fisiología
5.
Med Mycol ; 56(7): 877-883, 2018 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-29228375

RESUMEN

This study verified the influence of different temperatures on P. insidiosum in vitro zoosporogenesis. P. insidiosum isolates (n = 26) were submitted to zoosporogenesis and incubated at 5°C, 15°C, 20°C and 37°C (1st stage). Grass fragments were evaluated under optical microscopy at 4, 8, and 24 hours of incubation. Afterward, all isolates were incubated at 37°C and assessed at the same periods of time (2nd stage). The development of hyphae, presence of vesicles, zoosporangia and zoospores were checked. Only the presence of short hyphae was observed at 5°C. At 15°C, the hyphae were either under development or elongated and two isolates produced zoospores. When the isolates were submitted to 20°C for 4 hours, the presence of long and mycelial hyphae, vesicles, zoosporangia and zoospores was observed, which also happened at the other periods evaluated. In the second stage, the isolates which were initially at 5°C and 15°C evidenced long developing hyphae with the presence of vesicles, zoosporangia, and zoospores within 4 hours of incubation, and these characteristics were kept at the other evaluated periods. The isolates kept at 37°C showed evident zoosporogenesis in the first 4 hours of evaluation. It was concluded that temperatures of 20°C and 37°C support P. insidiosum zoosporogenesis process. On the other hand, 5°C and 15°C temperatures do not kill the microorganism.


Asunto(s)
Pythium/crecimiento & desarrollo , Pythium/efectos de la radiación , Esporas Fúngicas/crecimiento & desarrollo , Esporas Fúngicas/efectos de la radiación , Hifa/citología , Hifa/crecimiento & desarrollo , Hifa/efectos de la radiación , Microscopía , Pythium/citología , Esporas Fúngicas/citología , Temperatura
6.
J Liposome Res ; 26(3): 188-98, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26340033

RESUMEN

Amylin is a pancreatic hormone involved in the regulation of glucose metabolism and homeostasis. Restoration of the post-prandial and basal levels of human amylin in diabetic individuals is a key in controlling glycemia, controlling glucagon, reducing the insulin dose and increasing satiety, among other physiologic functions. Human amylin has a high propensity to aggregate. We have addressed this issue by designing a liposomal human amylin formulation. Nanoparticles of multilamellar liposomes comprising human amylin were obtained with 53% encapsulation efficiency. The in vitro kinetic release assay shows a biphasic profile. The stabilization of the lipidic nanoparticle against freeze-drying was achieved by using mannitol as a cryoprotectant, as evidenced by morphological characterization. The effectiveness of the human amylin entrapped in lipidic nanoparticles was tested by the measurement of its pharmacological effect in vivo after subcutaneous administration in mice. Collectively these results demonstrate the compatibility of human amylin with the lipidic interface as an effective pharmaceutical delivery system.


Asunto(s)
Polipéptido Amiloide de los Islotes Pancreáticos/química , Lípidos/química , Nanopartículas/química , Humanos , Cinética , Conformación Proteica
7.
J Biol Chem ; 289(41): 28324-37, 2014 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-25086037

RESUMEN

Protein aggregation into ß-sheet-enriched amyloid fibrils is associated with an increasing number of human disorders. The adoption of such amyloid conformations seems to constitute a generic property of polypeptide chains. Therefore, during evolution, proteins have adopted negative design strategies to diminish their intrinsic propensity to aggregate, including enrichment of gatekeeper charged residues at the flanks of hydrophobic aggregation-prone segments. Wild type transthyretin (TTR) is responsible for senile systemic amyloidosis, and more than 100 mutations in the TTR gene are involved in familial amyloid polyneuropathy. The TTR 26-57 segment bears many of these aggressive amyloidogenic mutations as well as the binding site for heparin. We demonstrate here that Lys-35 acts as a gatekeeper residue in TTR, strongly decreasing its amyloidogenic potential. This protective effect is sequence-specific because Lys-48 does not affect TTR aggregation. Lys-35 is part of the TTR basic heparin-binding motif. This glycosaminoglycan blocks the protective effect of Lys-35, probably by neutralization of its side chain positive charge. A K35L mutation emulates this effect and results in the rapid self-assembly of the TTR 26-57 region into amyloid fibrils. This mutation does not affect the tetrameric protein stability, but it strongly increases its aggregation propensity. Overall, we illustrate how TTR is yet another amyloidogenic protein exploiting negative design to prevent its massive aggregation, and we show how blockage of conserved protective features by endogenous factors or mutations might result in increased disease susceptibility.


Asunto(s)
Amiloide/química , Leucina/química , Lisina/química , Prealbúmina/química , Amiloide/genética , Amiloide/metabolismo , Neuropatías Amiloides Familiares/genética , Neuropatías Amiloides Familiares/metabolismo , Neuropatías Amiloides Familiares/patología , Expresión Génica , Heparina/química , Heparina/metabolismo , Humanos , Leucina/metabolismo , Lisina/metabolismo , Mutación , Prealbúmina/genética , Prealbúmina/metabolismo , Agregación Patológica de Proteínas , Multimerización de Proteína , Estabilidad Proteica , Estructura Secundaria de Proteína , Estructura Terciaria de Proteína , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Electricidad Estática
8.
J Biol Inorg Chem ; 19(6): 839-51, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24557708

RESUMEN

Conversion of prion protein (PrP) to an altered conformer, the scrapie PrP (PrP(Sc)), is a critical step in the development of transmissible spongiform encephalopathies. Both Cu(II) and nucleic acid molecules have been implicated in this conversion. Full-length PrP can bind up to six copper ions; four Cu(II) binding sites are located in the octarepeat domain (residues 60-91), and His-96 and His-111 coordinate two additional copper ions. Experimental evidence shows that PrP binds different molecules, resulting in diverse cellular signaling events. However, there is little information about the interaction of macromolecular ligands with Cu(II)-bound PrP. Both RNA and DNA sequences can bind PrP, and this interaction results in reciprocal conformational changes. Here, we investigated the interaction of Cu(II) and nucleic acids with amyloidogenic non-octarepeat PrP peptide models (comprising human PrP residues 106-126 and hamster PrP residues 109-149) that retain His-111 as the copper-anchoring residue. The effect of Cu(II) and DNA or RNA sequences in the aggregation, conformation, and toxicity of PrP domains was investigated at low and neutral pH. Circular dichroism and EPR spectroscopy data indicate that interaction of the PrP peptides with Cu(II) and DNA occurs at pH 7. This dual interaction induces conformational changes in the peptides, modulating their aggregation, and affecting the morphology of the aggregated species, resulting in different cytotoxic effects. These results provide new insights into the role of Cu(II) and nucleic acid sequences in the structural conversion and aggregation of PrP, which are both critical events related to prion pathogenesis.


Asunto(s)
Cobre/química , Metaloproteínas/farmacología , Ácidos Nucleicos/química , Péptidos/química , Priones/química , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Cricetinae , Relación Dosis-Respuesta a Droga , Humanos , Concentración de Iones de Hidrógeno , Metaloproteínas/química , Ratones , Relación Estructura-Actividad
9.
J Biol Chem ; 287(44): 37206-18, 2012 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-22918834

RESUMEN

The accumulation of amyloid fibrils is a feature of amyloid diseases, where cell toxicity is due to soluble oligomeric species that precede fibril formation or are formed by fibril fragmentation, but the mechanism(s) of fragmentation is still unclear. Neutrophil-derived elastase and histones were found in amyloid deposits from patients with different systemic amyloidoses. Neutrophil extracellular traps (NETs) are key players in a death mechanism in which neutrophils release DNA traps decorated with proteins such as elastase and histones to entangle pathogens. Here, we asked whether NETs are triggered by amyloid fibrils, reasoning that because proteases are present in NETs, protease digestion of amyloid may generate soluble, cytotoxic species. We show that amyloid fibrils from three different sources (α-synuclein, Sup35, and transthyretin) induced NADPH oxidase-dependent NETs in vitro from human neutrophils. Surprisingly, NET-associated elastase digested amyloid fibrils into short species that were cytotoxic for BHK-21 and HepG2 cells. In tissue sections from patients with primary amyloidosis, we also observed the co-localization of NETs with amyloid deposits as well as with oligomers, which are probably derived from elastase-induced fibril degradation (amyloidolysis). These data reveal that release of NETs, so far described to be elicited by pathogens, can also be triggered by amyloid fibrils. Moreover, the involvement of NETs in amyloidoses might be crucial for the production of toxic species derived from fibril fragmentation.


Asunto(s)
Amiloide/fisiología , Cromatina/metabolismo , Neutrófilos/patología , Acetofenonas/farmacología , Amiloide/química , Amiloide/genética , Neuropatías Amiloides Familiares/enzimología , Neuropatías Amiloides Familiares/genética , Neuropatías Amiloides Familiares/patología , Amiloidosis/enzimología , Amiloidosis/metabolismo , Amiloidosis/patología , Animales , Biomarcadores/metabolismo , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Cromatina/enzimología , Cricetinae , Espacio Extracelular/enzimología , Espacio Extracelular/metabolismo , Células Hep G2 , Humanos , Amiloidosis de Cadenas Ligeras de las Inmunoglobulinas , Pulmón/enzimología , Pulmón/metabolismo , Pulmón/patología , Mutación Missense , NADPH Oxidasas/antagonistas & inhibidores , NADPH Oxidasas/metabolismo , Neutrófilos/enzimología , Neutrófilos/metabolismo , Compuestos Onio/farmacología , Elastasa Pancreática , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/farmacología , Fragmentos de Péptidos/fisiología , Prealbúmina/química , Prealbúmina/genética , Prealbúmina/fisiología , Estructura Cuaternaria de Proteína , Proteolisis , Especies Reactivas de Oxígeno/metabolismo , Piel/enzimología , Piel/metabolismo , Piel/patología , alfa-Sinucleína/química , alfa-Sinucleína/genética , alfa-Sinucleína/fisiología
10.
J Biol Chem ; 287(33): 28152-62, 2012 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-22715097

RESUMEN

Over 50% of all human cancers lose p53 function. To evaluate the role of aggregation in cancer, we asked whether wild-type (WT) p53 and the hot-spot mutant R248Q could aggregate as amyloids under physiological conditions and whether the mutant could seed aggregation of the wild-type form. The central domains (p53C) of both constructs aggregated into a mixture of oligomers and fibrils. R248Q had a greater tendency to aggregate than WT p53. Full-length p53 aggregated into amyloid-like species that bound thioflavin T. The amyloid nature of the aggregates was demonstrated using x-ray diffraction, electron microscopy, FTIR, dynamic light scattering, cell viabilility assay, and anti-amyloid immunoassay. The x-ray diffraction pattern of the fibrillar aggregates was consistent with the typical conformation of cross ß-sheet amyloid fibers with reflexions of 4.7 Å and 10 Å. A seed of R248Q p53C amyloid oligomers and fibrils accelerated the aggregation of WT p53C, a behavior typical of a prion. The R248Q mutant co-localized with amyloid-like species in a breast cancer sample, which further supported its prion-like effect. A tumor cell line containing mutant p53 also revealed massive aggregation of p53 in the nucleus. We conclude that aggregation of p53 into a mixture of oligomers and fibrils sequestrates the native protein into an inactive conformation that is typical of a prionoid. This prion-like behavior of oncogenic p53 mutants provides an explanation for the negative dominance effect and may serve as a potential target for cancer therapy.


Asunto(s)
Amiloide/química , Mutación Missense , Neoplasias/química , Priones , Multimerización de Proteína , Proteína p53 Supresora de Tumor/química , Sustitución de Aminoácidos , Amiloide/genética , Amiloide/metabolismo , Benzotiazoles , Humanos , Neoplasias/genética , Neoplasias/metabolismo , Neoplasias/terapia , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Tiazoles/química , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Difracción de Rayos X
11.
Int J Mol Sci ; 14(3): 5284-311, 2013 Mar 06.
Artículo en Inglés | MEDLINE | ID: mdl-23466880

RESUMEN

Transthyretin (TTR) is a homotetrameric protein that circulates in plasma and cerebral spinal fluid (CSF) whose aggregation into amyloid fibrils has been associated with at least two different amyloid diseases: senile systemic amyloidosis (SSA) and familial amyloid polyneuropathy (FAP). In SSA aggregates are composed of WT-TTR, while in FAP more than 100 already-described variants have been found in deposits. Until now, TTR-related diseases have been untreatable, although a new drug called Tafamidis has been approved only in Europe to specifically treat V30M patients. Thus, new strategies are still necessary to treat FAP caused by other variants of TTR. TTR has two channels in the dimer interface that bind to the hormone thyroxin and that have been used to accommodate anti-amyloidogenic compounds. These compounds stabilize the tetramers, rendering TTR less amyloidogenic. Here, we investigated the effects of three non-steroidal anti-inflammatory compounds-sulindac (SUL), indomethacin (IND) and lumiracoxib (LUM)-as tetramer stabilizers and aggregation inhibitors. WT-TTR and the very aggressive TTR variant L55P were used as models. These compounds were able to stabilize TTR against high hydrostatic pressure (HHP), increasing the ΔGf by several kcal. They were also effective in inhibiting WT-TTR and L55P acid- or HHP-induced aggregation; in particular, LUM and IND were very effective, inhibiting almost 100% of the aggregation of both proteins under certain conditions. The species formed when aggregation was performed in the presence of these compounds were much less toxic to cells in culture. The crystal structures of WT-TTR bound to the three compounds were solved at high resolution, allowing the identification of the relevant protein:drug interactions. We discuss here the ligand-binding features of LUM, IND and SUL to TTR, emphasizing the critical interactions that render the protein more stable and less amyloidogenic.

12.
Biochemistry ; 51(27): 5402-13, 2012 Jul 10.
Artículo en Inglés | MEDLINE | ID: mdl-22691027

RESUMEN

A misfolded form of the prion protein (PrP) is the primary culprit in mammalian prion diseases. It has been shown that nucleic acids catalyze the misfolding of cellular PrP into a scrapie-like conformer. It has also been observed that the interaction of PrP with nucleic acids is nonspecific and that the complex can be toxic to cultured cells. No direct correlation has yet been drawn between changes in PrP structure and toxicity due to nucleic acid binding. Here we asked whether different aggregation, stability, and toxicity effects are detected when nonrelated DNA sequences interact with recombinant PrP. Using spectroscopic techniques to analyze PrP tertiary and secondary structure and cellular assays to assess toxicity, we found that rPrP-DNA interactions lead to different aggregated species, depending on the sequence and size of the oligonucleotide tested. A 21-mer DNA sequence (D67) induced higher levels of aggregation and also dissimilar structural changes in rPrP, compared to binding to oligonucleotides with the same length and different nucleotide sequences or different GC contents. The rPrP-D67 complex induced significant cell dysfunction, which appears to be correlated with the biophysical properties of the complex. Although sequence specificity is not apparent for PrP-nucleic acid interactions, we believe that particular nucleic acid patterns, possibly related to GC content, oligonucleotide length, and structure, govern PrP recognition. Understanding the structural and cellular effects observed for PrP-nucleic acid complexes may shed light on the still mysterious pathology of the prion protein.


Asunto(s)
Citotoxinas/química , Citotoxinas/toxicidad , ADN/metabolismo , Priones/química , Priones/toxicidad , Secuencia de Aminoácidos , Secuencia de Bases , Línea Celular Tumoral , Citotoxinas/metabolismo , ADN/genética , Humanos , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Fragmentos de Péptidos/metabolismo , Fragmentos de Péptidos/toxicidad , Priones/metabolismo , Unión Proteica , Multimerización de Proteína , Estabilidad Proteica , Estructura Cuaternaria de Proteína , Estructura Secundaria de Proteína , Solubilidad
13.
Rom J Ophthalmol ; 65(3): 275-278, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35036651

RESUMEN

Congenital hypertrophy of the retinal pigment epithelium is a rare benign tumor of the ocular fundus that may vary according to three types. It is frequently asymptomatic and diagnosed during routine ophthalmology exam. This lesion has an important differential diagnosis with retinal disease and may be related to systemic diseases, therefore, it is essential to recognize it and keep the follow-up. In this paper, three different cases of each type of CHRPE were described and documented. Abbreviations: CHRPE = Congenital hypertrophy of the Retinal Pigment Epithelium, RPE = Retinal Pigment Epithelium, CDVA = Corrected Distance Visual Acuity, PIO = Intraocular Pressure, FA = Fluorescein Angiography, FAP = Familial Adenomatous Polyposis, RPEH-FAP = Retinal Pigment Epithelial Hamartomas Associated with Familial Adenomatous Polyposis, OCT = Ocular Coherence Tomography.


Asunto(s)
Poliposis Adenomatosa del Colon , Enfermedades de la Retina , Angiografía con Fluoresceína , Humanos , Hipertrofia , Enfermedades de la Retina/diagnóstico , Epitelio Pigmentado de la Retina
14.
Neurochem Int ; 138: 104758, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32439533

RESUMEN

α-Synuclein protein (α-syn) is a central player in Parkinson's disease (PD) and in a spectrum of neurodegenerative diseases collectively known as synucleinopathies. These diseases are characterized by abnormal motor symptoms, such as tremor at rest, slowness of movement, rigidity of posture, and bradykinesia. Histopathological features of PD include preferential loss of dopaminergic neurons in the substantia nigra and formation of fibrillar intraneuronal inclusions called Lewy bodies and Lewy neurites, which are composed primarily of the α-syn protein. Currently, it is well accepted that α-syn oligomers (αSO) are the main toxic agent responsible for the etiology of PD. Glutamatergic excitotoxicity is associated with several neurological disorders, including PD. Excess glutamate in the synaptic cleft can be taken up by the astrocytic glutamate transporters GLAST and GLT-1. Although this event is the main defense against glutamatergic excitotoxicity, the molecular mechanisms that regulate this process have not yet been investigated in an early sporadic model of synucleinopathy. Here, using an early sporadic model of synucleinopathy, we demonstrated that the treatment of astrocytes with αSO increased glutamate uptake. This was associated with higher levels of GLAST and GLT-1 in astrocyte cultures and in a mouse model of synucleinopathy 24 h and 45 days after inoculation with αSO, respectively. Pharmacological inhibition of the TGF-ß1 (transforming growth factor beta 1) pathway in vivo reverted GLAST/GLT-1 enhancement induced by αSO injection. Therefore, our study describes a new neuroprotective role of astrocytes in an early sporadic model of synucleinopathy and sheds light on the mechanisms of glutamate transporter regulation for neuroprotection against glutamatergic excitotoxicity in synucleinopathy.


Asunto(s)
Sistema de Transporte de Aminoácidos X-AG/metabolismo , Astrocitos/metabolismo , Modelos Animales de Enfermedad , Sinucleinopatías/metabolismo , alfa-Sinucleína/toxicidad , Animales , Animales Recién Nacidos , Astrocitos/efectos de los fármacos , Astrocitos/patología , Células Cultivadas , Femenino , Ratones , Embarazo , Sinucleinopatías/inducido químicamente , Sinucleinopatías/patología , alfa-Sinucleína/química
15.
BMJ Paediatr Open ; 3(1): e000473, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31531405

RESUMEN

OBJECTIVES: To evaluate the ability of glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase (UCH-L1) to detect concussion in children and adult trauma patients with a normal mental status and assess biomarker concentrations over time as gradients of injury in concussive and non-concussive head and body trauma. DESIGN: Large prospective cohort study. SETTING: Three level I trauma centres in the USA. PARTICIPANTS: Paediatric and adult trauma patients of all ages, with and without head trauma, presenting with a normal mental status (Glasgow Coma Scale score of 15) within 4 hours of injury. Rigorous screening for concussive symptoms was conducted. Of 3462 trauma patients screened, 751 were enrolled and 712 had biomarker data. Repeated blood sampling was conducted at 4, 8, 12, 16, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 144, 156, 168 and 180 hours postinjury in adults. MAIN OUTCOMES: Detection of concussion and gradients of injury in children versus adults by comparing three groups of patients: (1) those with concussion; (2) those with head trauma without overt signs of concussion (non-concussive head trauma controls) and (3) those with peripheral (body) trauma without head trauma or concussion (non-concussive body trauma controls). RESULTS: A total of 1904 samples from 712 trauma patients were analysed. Within 4 hours of injury, there were incremental increases in levels of both GFAP and UCH-L1 from non-concussive body trauma (lowest), to mild elevations in non-concussive head trauma, to highest levels in patients with concussion. In concussion patients, GFAP concentrations were significantly higher compared with body trauma controls (p<0.001) and with head trauma controls (p<0.001) in both children and adults, after controlling for multiple comparisons. However, for UCH-L1, there were no significant differences between concussion patients and head trauma controls (p=0.894) and between body trauma and head trauma controls in children. The AUC for initial GFAP levels to detect concussion was 0.80 (0.73-0.87) in children and 0.76 (0.71-0.80) in adults. This differed significantly from UCH-L1 with AUCs of 0.62 (0.53-0.72) in children and 0.69 (0.64-0.74) in adults. CONCLUSIONS: In a cohort of trauma patients with normal mental status, GFAP outperformed UCH-L1 in detecting concussion in both children and adults. Blood levels of GFAP and UCH-L1 showed incremental elevations across three injury groups: from non-concussive body trauma, to non-concussive head trauma, to concussion. However, UCH-L1 was expressed at much higher levels than GFAP in those with non-concussive trauma, particularly in children. Elevations in both biomarkers in patients with non-concussive head trauma may be reflective of a subconcussive brain injury. This will require further study.

16.
Mater Sci Eng C Mater Biol Appl ; 79: 802-811, 2017 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-28629083

RESUMEN

Insulin-loaded calcium phosphate nanoparticles have been proposed as a potential drug delivery system for the oral treatment of diabetes and to stimulate bone cell proliferation and bone mineralization. The kinetics of insulin incorporation onto hydroxyapatite (HA) and Sr (SrHA)- and Zn (ZnHA)-substituted hydroxyapatite nanoparticles was investigated using X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, zeta potential measurements and circular dichroism (CD) spectroscopy. The increase in insulin concentration on HA, SrHA and ZnHA was a typical physical adsorption process controlled by electrostatic forces and followed a Freundlich isotherm model. Zn substitution enhanced the capacity of the apatite surface to adsorb insulin, whereas Sr substitution inhibited insulin uptake. The surface stoichiometry and mesopore specific area induced by Zn and Sr substitution are proposed as the main causes of the difference in insulin adsorption. Despite the weak interaction between insulin and the apatite surface, the CD spectra revealed a decrease in the insulin ellipticity when the protein was adsorbed on the HA, SrHA and ZnHA nanoparticles. A reduction in alpha-helical structures and an increase in beta sheets were observed when insulin interacted with the HA surface. A less pronounced effect was found for ZnHA, for which a subtle decrease in alpha-helical structures was followed by an increase in turn structures. Interaction with the SrHA surface did not change the native insulin conformation. In vitro cell culture experiments lasting 24h using F-OST stromal cells showed that the insulin loaded on HA and ZnHA did not affect cell proliferation but the insulin loaded on SrHA improved cell proliferation. These results suggest that the stability of the native protein conformation is an important factor to consider when cells interact with insulin adsorbed on metal-substituted HA surfaces.


Asunto(s)
Durapatita/química , Adsorción , Insulina , Espectroscopía Infrarroja por Transformada de Fourier , Estroncio , Zinc
17.
Psicol. esc. educ ; 26: e232253, 2022. tab
Artículo en Portugués | LILACS, Index Psi Revistas Técnico-Científicas | ID: biblio-1406416

RESUMEN

Este estudo teve como objetivo verificar a associação entre os recursos do ambiente familiar e a leitura de adolescentes. Participaram 106 adolescentes, de ambos os sexos, de 11 a 16 anos, sem queixas de dificuldades de aprendizagem. Para a coleta de dados utilizou-se um texto narrativo, o questionário de múltipla escolha sobre o texto e o de Recursos do Ambiente Familiar, adaptado. Foi realizada a análise descritiva e inferencial por meio dos testes correlação de Spearman, Mann-Whitney e Kruskal Wallis, com nível de significância de 5%. Os recursos que promovem os processos proximais e as práticas parentais contribuíram para um melhor desempenho de leitura. Em contrapartida, a categoria de atividades previsíveis contribuiu negativamente. Assim, o ambiente e os recursos influenciaram o desempenho leitor dos adolescentes. Conclui-se que é importante a elaboração de medidas escolares e de políticas públicas, para fortalecer a relação família-escola, ampliar os recursos familiares e tornar o ambiente favorável ao ensino.


En este estudio se tuvo como objetivo verificar la asociación entre los recursos del ambiente familiar y la lectura de adolescentes. Participaron 106 adolescentes, de ambos sexos, de 11 a 16 años, sin quejas de dificultades de aprendizaje. Para la recopilación de datos se utilizó un texto narrativo, el cuestionario de múltiple elección sobre el texto y el de Recursos del Ambiente Familiar, adaptado. Se realizó el análisis descriptivo e inferencial por intermedio de las pruebas correlación de Spearman, Mann-Whitney y Kruskal Wallis, con nivel de significancia del 5%. Los recursos que promueven los procesos proximales y las prácticas parentales contribuyeron al mejor rendimiento de lectura. Por otro lado, la categoría de actividades previsibles contribuyó negativamente. Así, el ambiente y los recursos influenciaron el rendimiento lector de los adolescentes. Se concluye que es importante la elaboración de medidas escolares y de políticas públicas, para fortalecer la relación familia-escuela, ampliar los recursos familiares y tornar el ambiente favorable a la enseñanza.


This study aimed to verify the association between the resources of the family environment and teenage reading. A total of 106 adolescents of both sexes, aged between 11 and 16 years, without learning difficulties, participated in the study. For data collection, a narrative text, a multiple-choice questionnaire about the text and an adapted Family Environment Resources questionnaire were used. Descriptive and inferential analysis was performed using Spearman, Mann-Whitney and Kruskal Wallis correlation tests, with a significance level of 5%. Resources that promote proximal processes and parenting practices contributed to better reading performance. In contrast, the predictable activities category contributed negatively. Thus, the environment and resources influenced the adolescents' reading performance. It is concluded that the elaboration of school measures and public policies is important to strengthen the family-school relationship, expand family resources and make the environment favorable to teaching.


Asunto(s)
Lectura , Instituciones Académicas , Relaciones Familiares , Discapacidades para el Aprendizaje
18.
Rev. enferm. UERJ ; 30: e65487, jan. -dez. 2022.
Artículo en Inglés, Portugués | LILACS-Express | LILACS | ID: biblio-1399672

RESUMEN

Objetivo: analisar as práticas profissionais no primeiro encontro dos pais com recém-nascido na unidade neonatal. Método: estudo quantitativo, descritivo e transversal, desenvolvido com 69 profissionais de saúde da unidade de terapia intensiva neonatal de um Hospital Universitário no Rio de Janeiro, após aprovação pelo Comitê de Ética em Pesquisa. Os dados foram coletados no período de março a julho de 2021, por meio de questionário online, e analisados mediante estatística descritiva simples, percentual e média. Resultados: as práticas profissionais foram adequadas quanto possibilitar aos pais: o toque materno/paterno (91,3%); o livre acesso à unidade neonatal (86,9%); e a realização de cuidados com o bebê (81,1%). Conclusão: a maioria das práticas profissionais está alinhada às recomendações do Método Canguru. Contudo, as fragilidades relativas ao acolhimento evidenciam lacunas na abordagem da temática na formação profissional e em atividades de educação continuada.


Objective: to examine the professional practices in the first meeting between parents and newborn in the neonatal unit. Method: in this quantitative, descriptive, cross-sectional study conducted with 69 health personnel from the neonatal intensive care unit of a university hospital in Rio de Janeiro, after approval by the research ethics committee, data were collected from March to July 2021 by online survey and analyzed using simple percentage and average descriptive statistics. Results: the professional practices were appropriate in that they allowed parents: maternal/paternal touch (91.3%); free access to the neonatal unit (86.9%); and to provide care for the baby (81.1%). Conclusion: the professional practices were mostly in line with the recommendations of the Kangaroo Method. However, weaknesses in receptiveness highlighted gaps in how the subject was approached in training activities and continued professional development.


Objetivo: analizar las prácticas profesionales en el primer encuentro entre padres y recién nacido en la unidad neonatal. Método: estudio cuantitativo, descriptivo y transversal, desarrollado con 69 profesionales de la salud de la unidad de cuidados intensivos neonatales de un Hospital Universitario de Rio de Janeiro, previa aprobación del Comité de Ética en Investigación. Los datos fueron recolectados de marzo a julio de 2021, a través de una encuesta en línea, y analizados mediante estadística descriptiva simple, porcentaje y promedio. Resultados: las prácticas profesionales fueron adecuadas en cuanto a posibilitar a los padres: el toque materno/paterno (91,3%); el libre acceso a la unidad neonatal (86,9%); y la prestación de cuidados al bebé (81,1%). Conclusión: la mayoría de las prácticas profesionales está acorde con las recomendaciones del Método Canguro. Sin embargo, las debilidades relacionadas con la acogida evidencian lagunas acerca del enfoque del tema en la formación profesional y en actividades de educación continua.

19.
J Neurotrauma ; 34(13): 2132-2140, 2017 07 01.
Artículo en Inglés | MEDLINE | ID: mdl-28158951

RESUMEN

This study examined the performance of serum ubiquitin C-terminal hydrolase (UCH-L1) in detecting traumatic intracranial lesions on computed tomography (CT) scan (+CT) in children and youth with mild and moderate TBI (mmTBI) and assessed its performance in trauma control patients without head trauma. This prospective cohort study enrolled children and youth presenting to three level 1 trauma centers after blunt head trauma and a Glasgow Coma Scale (GCS) score of 9-15 as well as trauma control patients with GCS 15 that did not have blunt head trauma. The primary outcome measure was the presence of intracranial lesions on initial CT scan. Blood samples were obtained in all patients within 6 h of injury and measured by enzyme-linked immunosorbent assay ELISA for UCH-L1 (ng/mL). A total of 256 children and youth were enrolled in the study and had serum samples drawn within 6 h of injury for analysis; 196 had blunt head trauma and 60 were trauma controls. CT scan of the head was performed in 151 patients and traumatic intracranial lesions on CT scan were evident in 17 (11%), all of whom had a GCS of 13-15. The area under the receiver operating characteristic curve (AUC) for UCH-L1 in detecting children and youth with traumatic intracranial lesions on CT was 0.83 (95% confidence interval [CI], 0.73-0.93). In those presenting with a GCS of 15, the AUC for detecting lesions was 0.83 (95% CI, 0.72-0.94). Similarly, in children under 5 years of age, the AUC was 0.79 (95% CI, 0.59-1.00). Performance for detecting intracranial lesions at a UCH-L1 cut-off level of 0.18 ng/mL yielded a sensitivity of 100%, a specificity of 47%, and a negative predictive value of 100%. UCH-L1 showed good performance in infants and toddlers younger than 5 years and performed well in children and youth with a GCS score of 15. Before clinical application, further study in larger cohort of children and youth with mild TBI is warranted.


Asunto(s)
Conmoción Encefálica/diagnóstico , Encéfalo/diagnóstico por imagen , Traumatismos Cerrados de la Cabeza/diagnóstico , Tomografía Computarizada por Rayos X , Ubiquitina Tiolesterasa/sangre , Adolescente , Biomarcadores/sangre , Conmoción Encefálica/sangre , Conmoción Encefálica/diagnóstico por imagen , Niño , Preescolar , Femenino , Escala de Coma de Glasgow , Traumatismos Cerrados de la Cabeza/sangre , Traumatismos Cerrados de la Cabeza/diagnóstico por imagen , Humanos , Lactante , Recién Nacido , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Sensibilidad y Especificidad , Adulto Joven
20.
Behav Brain Res ; 333: 150-160, 2017 08 30.
Artículo en Inglés | MEDLINE | ID: mdl-28668282

RESUMEN

Parkinson's disease (PD) is characterized by motor dysfunction, which is preceded by a number of non-motor symptoms including olfactory deficits. Aggregation of α-synuclein (α-syn) gives rise to Lewy bodies in dopaminergic neurons and is thought to play a central role in PD pathology. However, whether amyloid fibrils or soluble oligomers of α-syn are the main neurotoxic species in PD remains controversial. Here, we performed a single intracerebroventricular (i.c.v.) infusion of α-syn oligomers (α-SYOs) in mice and evaluated motor and non-motor symptoms. Familiar bedding and vanillin essence discrimination tasks showed that α-SYOs impaired olfactory performance of mice, and decreased TH and dopamine levels in the olfactory bulb early after infusion. The olfactory deficit persisted until 45days post-infusion (dpi). α- SYO-infused mice behaved normally in the object recognition and forced swim tests, but showed increased anxiety-like behavior in the open field and elevated plus maze tests 20 dpi. Finally, administration of α-SYOs induced late motor impairment in the pole test and rotarod paradigms, along with reduced TH and dopamine content in the caudate putamen, 45 dpi. Reduced number of TH-positive cells was also seen in the substantia nigra of α-SYO-injected mice compared to control. In conclusion, i.c.v. infusion of α-SYOs recapitulated some of PD-associated non-motor symptoms, such as increased anxiety and olfactory dysfunction, but failed to recapitulate memory impairment and depressive-like behavior typical of the disease. Moreover, α-SYOs i.c.v. administration induced motor deficits and loss of TH and dopamine levels, key features of PD. Results point to α-syn oligomers as the proximal neurotoxins responsible for early non-motor and motor deficits in PD and suggest that the i.c.v. infusion model characterized here may comprise a useful tool for identification of PD novel therapeutic targets and drug screening.


Asunto(s)
Síntomas Conductuales/etiología , Encéfalo/efectos de los fármacos , Trastornos del Olfato/etiología , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/etiología , alfa-Sinucleína/toxicidad , Animales , Encéfalo/metabolismo , Células Cultivadas , Discriminación en Psicología/efectos de los fármacos , Modelos Animales de Enfermedad , Embrión de Mamíferos , Humanos , Inyecciones Intraventriculares , Masculino , Aprendizaje por Laberinto/efectos de los fármacos , Mesencéfalo/citología , Ratones , Ratones Transgénicos , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Péptidos/toxicidad , Reconocimiento en Psicología/efectos de los fármacos , Tirosina 3-Monooxigenasa/metabolismo , alfa-Sinucleína/química , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
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