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1.
Int J Biol Macromol ; 272(Pt 2): 132883, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38838898

RESUMO

Glycyrrhiza glabra extract is widely known for its antioxidant and anti-inflammatory properties and can improve the wound healing process. The aim of this work was to shorten the time of the healing process by using an eco-sustainable wound dressing based on Spanish broom flexible cellulosic fabric by impregnation with G. glabra extract-loaded ethosomes. Chemical analysis of G. glabra extract was performed by LC-DAD-MS/MS and its encapsulation into ethosomes was obtained using the ethanol injection method. Lipid vesicles were characterized in terms of size, polydispersity index, entrapment efficiency, zeta potential, and stability. In vitro release studies, biocompatibility, and scratch test on 3T3 fibroblasts were performed. Moreover, the structure of Spanish broom dressing and its ability to absorb wound exudate was characterized by Synchrotron X-ray phase contrast microtomography (SR-PCmicroCT). Ethosomes showed a good entrapment efficiency, nanometric size, good stability over time and a slow release of polyphenols compared to the free extract, and were not cytotoxic. Lastly, the results revealed that Spanish broom wound dressing loaded with G. glabra ethosomes is able to accelerate wound closure by reducing wound healing time. To sum up, Spanish broom wound dressing could be a potential new green tool for biomedical applications.


Assuntos
Bandagens , Celulose , Glycyrrhiza , Extratos Vegetais , Spartium , Cicatrização , Animais , Camundongos , Glycyrrhiza/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Cicatrização/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Spartium/química , Células 3T3
2.
Talanta ; 202: 251-258, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31171178

RESUMO

The quantitative uptake of Silica nanoparticles (SiNPs), although representing an essential prerequisite for their theranostic use, is difficult to address and it is still not utterly investigated. In this study, we tested the uptake and toxicity of two different types of luminescent core-shell silica-PEG (polyethylene glycol) nanoparticles SiNP and their carboxylate analogues on human adenocarcinoma cell line LoVo. We assessed the intracellular spatial distribution and concentration of Si element in the cell by a state-of-the-art approach merging synchrotron-based X-ray techniques (XRFM) with scanning transmission X-Ray microscopy (STXM). The concentration maps of Si obtained reflect the distribution of the SiNPs. In addition, we calculated the number of SiNPs per volume unit in each single cell, quantitating the exact amount of conveyed particles. The absence of effects on proliferation and cell death was confirmed by viability assays, morphological analysis and cytofluorimetric evaluation of ROS content. The three-dimensional analysis of intracellular uptake of both types of nanoparticles (with different surface charge) was performed by confocal fluorescence microscopy, which showed a main localization in the cytosolic region with no sign of nuclear uptake.


Assuntos
Neoplasias do Colo/química , Nanopartículas/análise , Dióxido de Silício/análise , Síncrotrons , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Neoplasias do Colo/patologia , Humanos , Microscopia de Fluorescência , Dióxido de Silício/síntese química , Dióxido de Silício/farmacologia , Espectrometria por Raios X , Células Tumorais Cultivadas , Raios X
3.
Biochem Biophys Res Commun ; 467(2): 348-53, 2015 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-26433123

RESUMO

Osteosarcoma (OS) is the most common primary malignant tumor of bone, occurring most frequently in children and adolescents. The mechanism of formation and development of OS have been studied for a long time. Tumor suppressor pathway governed by p53 gene are known to be involved in the pathogenesis of osteosarcoma. Moreover, loss of wild-type p53 activity is thought to be a major predictor of failure to respond to chemotherapy in various human cancers. In previous studies, we described the activity of a new indole derivative, NSC743420, belonging to the tubulin inhibitors family, capable to induce apoptosis and arrest of the cell cycle in the G2/M phase of various cancer cell lines. However, this molecule has never been tested on OS cell line. Here we address the activity of NSC743420 by examine whether differences in the p53 status could influence its effects on cell proliferation and death of OS cells. In particular, we compared the effect of the tested molecule on p53-wild type and p53-silenced U2OS cells, and on SaOS2 cell line, which is null for p53. Our results demonstrated that NSC743420 reduces OS cell proliferation by p53-dependent and p53-independent mechanisms. In particular, the molecule induces proliferative arrest that culminate to apoptosis in SaOS2 p53-null cells, while it brings a cytostatic and differentiating effect in U2OS cells, characterized by the cell cycle arrest in G0/G1 phase and increased alkaline phosphatase activity.


Assuntos
Antineoplásicos/farmacologia , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Indóis/farmacologia , Osteoblastos/efeitos dos fármacos , Tiazóis/farmacologia , Proteína Supressora de Tumor p53/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Inibidor de Quinase Dependente de Ciclina p21/genética , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Expressão Gênica , Humanos , Osteoblastos/metabolismo , Osteoblastos/patologia , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/metabolismo
4.
AJNR Am J Neuroradiol ; 36(7): 1259-65, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25792533

RESUMO

BACKGROUND AND PURPOSE: Brain white matter is frequently affected in mitochondrial diseases; optic atrophy gene 1-autosomal dominant optic atrophy and Leber hereditary optic neuropathy are the most frequent mitochondrial monosymptomatic optic neuropathies. In this observational study, brain white matter microstructure was characterized by DTI in patients with optic atrophy gene 1-autosomal dominant optic atrophy and Leber hereditary optic neuropathy, in relation to clinical and genetic features. MATERIALS AND METHODS: Nineteen patients with optic atrophy gene 1-autosomal dominant optic atrophy and 17 with Leber hereditary optic neuropathy older than 18 years of age, all genetically diagnosed, and 19 healthy volunteers underwent DTI by using a 1.5T MR imaging scanner and neurologic and ophthalmologic assessments. Brain white matter DTI metrics were calculated for all participants, and, in patients, their correlations with genetics and clinical findings were calculated. RESULTS: Compared with controls, patients with optic atrophy gene 1-autosomal dominant optic atrophy had an increased mean diffusivity in 29.2% of voxels analyzed within major white matter tracts distributed throughout the brain, while fractional anisotropy was reduced in 30.3% of voxels. For patients with Leber hereditary optic neuropathy, the proportion of altered voxels was only 0.5% and 5.5%, respectively, of which half was found within the optic radiation and 3.5%, in the smaller acoustic radiation. In almost all regions, fractional anisotropy diminished with age in patients with optic atrophy gene 1-autosomal dominant optic atrophy and correlated with average retinal nerve fiber layer thickness in several areas. Mean diffusivity increased in those with a missense mutation. Patients with Leber hereditary optic neuropathy taking idebenone had slightly milder changes. CONCLUSIONS: Patients with Leber hereditary optic neuropathy had preferential involvement of the optic and acoustic radiations, consistent with trans-synaptic degeneration, whereas patients with optic atrophy gene 1-autosomal dominant optic atrophy presented with widespread involvement suggestive of a multisystemic, possibly a congenital/developmental, disorder. White matter changes in Leber hereditary optic neuropathy and optic atrophy gene 1-autosomal dominant optic atrophy may be exploitable as biomarkers.


Assuntos
Imagem de Tensor de Difusão , Atrofia Óptica Autossômica Dominante/patologia , Atrofia Óptica Hereditária de Leber/patologia , Substância Branca/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
5.
Neuroradiology ; 55(8): 1017-1025, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23703033

RESUMO

INTRODUCTION: MRI, proton magnetic resonance spectroscopy (¹H-MRS), and diffusion tensor imaging (DTI) have been shown to be of great prognostic value in term newborns with moderate-severe hypoxic-ischemic encephalopathy (HIE). Currently, no data are available on ¹H-MRS and DTI performed in the subacute phase after hypothermic treatment. The aim of the present study was to assess their prognostic value in newborns affected by moderate-severe HIE and treated with selective brain cooling (BC). METHODS: Twenty infants treated with BC underwent conventional MRI and (1)H-MRS at a mean (SD) age of 8.3 (2.8) days; 15 also underwent DTI. Peak area ratios of metabolites and DTI variables, namely mean diffusivity (MD), axial and radial diffusivity, and fractional anisotropy (FA), were calculated. Clinical outcome was monitored until 2 years of age. RESULTS: Adverse outcome was observed in 6/20 newborns. Both ¹H-MRS and DTI variables showed higher prognostic accuracy than conventional MRI. N-acetylaspartate/creatine at a basal ganglia localisation showed 100% PPV and 93% NPV for outcome. MD showed significantly decreased values in many regions of white and gray matter, axial diffusivity showed the best predictive value (PPV and NPV) in the genu of corpus callosum (100 and 91%, respectively), and radial diffusivity was significantly decreased in fronto white matter (FWM) and fronto parietal (FP) WM. The decrement of FA showed the best AUC (0.94) in the FPWM. CONCLUSION: Selective BC in HIE neonates does not affect the early and accurate prognostic value of ¹H-MRS and DTI, which outperform conventional MRI.


Assuntos
Encéfalo/metabolismo , Encéfalo/patologia , Crioterapia/métodos , Imagem de Tensor de Difusão/métodos , Hipóxia-Isquemia Encefálica/diagnóstico , Hipóxia-Isquemia Encefálica/terapia , Imageamento por Ressonância Magnética/métodos , Biomarcadores/análise , Feminino , Humanos , Hipóxia-Isquemia Encefálica/metabolismo , Recém-Nascido , Masculino , Prognóstico , Prótons , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Resultado do Tratamento
6.
Eur J Neurol ; 19(7): 1045-9, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22175823

RESUMO

BACKGROUND AND PURPOSE: The aim of this study was to evaluate the presence of abnormalities in the brain of patients with restless legs syndrome (RLS) using voxel-based morphometry and diffusion tensor imaging (DTI). METHODS: Twenty patients and twenty controls were studied. Voxel-based morphometry analysis was performed using statistical parametric mapping (SPM8) and FSL-VBM software tools. For voxel-wise analysis of DTI, tract-based spatial statistics (TBSS) and SPM8 were used. RESULTS: Applying an appropriate threshold of probability, no significant results were found either in comparison or in correlation analyses. CONCLUSIONS: Our data argue against clear structural or microstructural abnormalities in the brain of patients with idiopathic RLS, suggesting a prevalent role of functional or metabolic impairment.


Assuntos
Mapeamento Encefálico/métodos , Imagem de Tensor de Difusão/métodos , Síndrome das Pernas Inquietas/patologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Síndrome das Pernas Inquietas/epidemiologia
7.
Biochim Biophys Acta ; 1807(9): 1244-9, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21722623

RESUMO

In this study we assessed ΔG'(ATP) hydrolysis, cytosolic [ADP], and the rate of phosphocreatine recovery using Phosphorus Magnetic Resonance Spectroscopy in the calf muscle of a group of patients affected by glycogen myo-phosphorylase deficiency (McArdle disease). The goal was to ascertain whether and to what extent the deficit of the glycogenolytic pathway would affect the muscle energy balance. A typical feature of this pathology is the lack of intracellular acidosis. Therefore we posed the question of whether, in the absence of pH decrease, the rate of phosphocreatine recovery depends on the amount of phosphocreatine consumed during exercise. Results showed that at the end of exercise both [ADP] and ΔG'(ATP) of patients were significantly higher than those of matched control groups reaching comparable levels of phosphocreatine concentration. Furthermore, in these patients we found that the rate of phosphocreatine recovery is not influenced by the amount of phosphocreatine consumed during exercise. These outcomes provide experimental evidence that: i) the intracellular acidification occurring in exercising skeletal muscle is a protective factor for the energy consumption; and ii) the influence of pH on the phosphocreatine recovery rate is at least in part related to the kinetic mechanisms of mitochondrial creatine kinase enzyme.


Assuntos
Músculos/metabolismo , Fosforilases/metabolismo , Adulto , Feminino , Humanos , Concentração de Íons de Hidrogênio , Cinética , Espectroscopia de Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Músculos/enzimologia , Isótopos de Fósforo , Termodinâmica
8.
Neurology ; 74(12): 988-94, 2010 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-20308683

RESUMO

OBJECTIVE: The aim of our study was to investigate the microstructural integrity of brain regions functionally involved in the tremor loop in patients with familial essential tremor (FET), using diffusion tensor imaging (DTI). METHODS: Twenty-five patients with FET, 15 patients with Parkinson disease (PD), and 15 healthy subjects were studied. DTI was performed to measure fractional anisotropy (FA) and mean diffusivity (MD) in various regions of interest: red nucleus, dentate nucleus (DN), cerebellar white matter, middle (MCP) and superior cerebellar peduncle (SCP), and ventrolateral thalamus. RESULTS: In patients with FET, FA values in the DN (median 0.19, range 0.13-0.23) were reduced (p < 0.001) compared with patients with PD (median 0.37, range 0.32-0.58) and healthy controls (median 0.36, range 0.33-0.40). In patients with FET, FA was also reduced (p = 0.003) and MD values increased (p < 0.001) in the SCP compared with patients with PD and healthy controls. Among patients with FET, those with longer disease duration showed FA values in the DN lower than those with shorter disease duration (p = 0.018). Patients with FET could be completely distinguished from both patient with PD and healthy controls using FA values of the DN alone. CONCLUSION: Neuroimaging evidence of microstructural changes consistent with neurodegeneration was found in the dentate nucleus (DN) and SCP of patients with familial essential tremor. This suggests that neurodegenerative pathology of cerebellar structures may play a role in essential tremor. Further studies are needed to assess the role of fractional anisotropy and mean diffusivity changes in DN and SCP in the differential diagnosis of essential tremor and Parkinson disease, which may present similar clinical signs at the onset of disease.


Assuntos
Cerebelo/patologia , Tremor Essencial/patologia , Análise de Variância , Anisotropia , Cerebelo/citologia , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/patologia , Valores de Referência , Reprodutibilidade dos Testes
9.
Cephalalgia ; 30(5): 552-9, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-19673908

RESUMO

We used multimodal magnetic resonance (MR) techniques [brain diffusion-weighted magnetic resonance imaging, diffusion-weighted imaging (DWI), proton MR spectroscopy (MRS), (1)H-MRS; and skeletal muscle phosphorous MRS, (31)P-MRS] to investigate interictal brain microstructural changes and tissue energy metabolism in four women with genetically determined familial hemiplegic migraine type 2 (FHM2), belonging to two unrelated families, compared with 10 healthy women. Brain DWI revealed a significant increase of the apparent diffusion coefficient median values in the vermis and cerebellar hemispheres of FHM2 patients, preceding in two subjects the onset of interictal cerebellar deficits. (31)P-MRS revealed defective energy metabolism in skeletal muscle of FHM2 patients, while brain (1)H-MRS showed a mild pathological increase in lactate in the lateral ventricles of one patient and a mild reduction of cortical N-acetyl-aspartate to creatine ratio in another one. Our MRS results showed that a multisystem energy metabolism defect in FHM2 is associated with microstructural cerebellar changes detected by DWI, even before the onset of cerebellar symptoms.


Assuntos
Doenças Cerebelares/fisiopatologia , Músculo Esquelético/fisiopatologia , Adulto , Doenças Cerebelares/metabolismo , Doenças Cerebelares/patologia , Cerebelo/metabolismo , Cerebelo/patologia , Cerebelo/fisiopatologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Enxaqueca com Aura/metabolismo , Enxaqueca com Aura/patologia , Enxaqueca com Aura/fisiopatologia , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia
10.
NMR Biomed ; 22(10): 1003-13, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19504521

RESUMO

This study extensively investigates different strategies for the absolute quantitation of N-acetyl aspartate, creatine and choline in white and grey matter by (1)H-MRS at 1.5 T. The main focus of this study was to reliably estimate metabolite concentrations while reducing the scan time, which remains as one of the main problems in clinical MRS. Absolute quantitation was based on the water-unsuppressed concentration as the internal standard. We compared strategies based on various experimental protocols and post-processing strategies. Data were obtained from 30 control subjects using a PRESS sequence at several TE to estimate the transverse relaxation time, T(2), of the metabolites. Quantitation was performed with the algorithm QUEST using two different metabolite signal basis sets: a whole-metabolite basis set (WhoM) and a basis set in which the singlet signals were split from the coupled signals (MSM). The basis sets were simulated in vivo for each TE used. Metabolites' T(2)s were then determined by fitting the estimated signal amplitudes of the metabolites obtained at different TEs. Then the absolute concentrations (mM) of the metabolites were assessed for each subject using the estimated signal amplitudes and either the mean estimated relaxation times of all subjects (mean protocol, MP) or the T(2) estimated from the spectra derived from the same subject (individual protocol, IP). Results showed that MP represents a less time-consuming alternative to IP in the quantitation of brain metabolites by (1)H-MRS in both grey and white matter, with a comparable accuracy when performed by MSM. It was also shown that the acquisition time might be further reduced by using a variant of MP, although with reduced accuracy. In this variant, only one water-suppressed and one water-unsuppressed spectra were acquired, drastically reducing the duration of the entire MRS examination. However, statistical analysis highlights the reduced accuracy of MP when performed using WhoM, particularly at longer echo times.


Assuntos
Ácido Aspártico/análogos & derivados , Encéfalo , Colina/metabolismo , Creatina/metabolismo , Espectroscopia de Ressonância Magnética/métodos , Adulto , Ácido Aspártico/metabolismo , Encéfalo/anatomia & histologia , Encéfalo/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Processamento de Sinais Assistido por Computador , Água/metabolismo , Adulto Jovem
11.
Neurology ; 72(16): 1425-31, 2009 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-19380702

RESUMO

OBJECTIVE: The cause of hyperintense magnetic resonance changes and reduced apparent diffusion coefficient (ADC) in specific brain regions of patients with Creutzfeldt-Jakob disease (CJD) is unknown. Our aim was to determine the neuropathologic correlates of antemortem water ADC and normalized T2-weighted changes in patients with CJD. METHOD: Ten patients with CJD and 10 sex- and age-matched healthy controls were studied by DWI and T2-weighted echoplanar MRI. At postmortem, patients with CJD were evaluated for semiquantitative assessment of gliosis and neuronal loss, spongiform changes, and abnormal PrP protein deposition in four cortical regions (occipital, parietal, and temporal cortex, and cingulate gyrus), thalamus, and striatum for a total of 60 regions of interest (ROI). RESULTS: Gliosis and neuronal loss correlated very highly with each other in the 60 ROIs. Where status spongiosus was absent, spongiform change correlated very highly with gliosis and neuronal loss in the cortex, but not in deep gray matter. Spongiform change was also significantly correlated with PrPSc load in both cortical and deep gray ROIs. In deep gray matter, ADC decreased with increasing spongiform change (R2 = 0.78; p < 0.001) and PrPSc load (R2 = 0.51; p = 0.003). In the cortex, ADC decreased with increases in all three, highly correlated, pathologic scores. CONCLUSION: Antemortem reductions in ADC values, typically found in patients with Creutzfeldt-Jakob disease (CJD), are correlated with spongiform changes seen at autopsy. This could be clearly established in the striatum and thalamus of our patients with CJD where the extent of spongiform change was not significantly correlated with gliosis or neuronal loss.


Assuntos
Encéfalo/patologia , Síndrome de Creutzfeldt-Jakob/patologia , Imagem de Difusão por Ressonância Magnética/métodos , Adulto , Idoso , Autopsia , Gânglios da Base/patologia , Gânglios da Base/fisiopatologia , Encéfalo/fisiopatologia , Mapeamento Encefálico/métodos , Córtex Cerebral/patologia , Córtex Cerebral/fisiopatologia , Síndrome de Creutzfeldt-Jakob/fisiopatologia , Progressão da Doença , Feminino , Gliose/patologia , Gliose/fisiopatologia , Humanos , Processamento de Imagem Assistida por Computador/métodos , Masculino , Pessoa de Meia-Idade , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Valor Preditivo dos Testes , Tálamo/patologia , Tálamo/fisiopatologia
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