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1.
J Endocrinol Invest ; 46(8): 1695-1703, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36840841

RESUMO

PURPOSE: Laboratory, imaging, and pathological features of Graves' disease (GD), although well characterized, have been barely correlated each other. Aim of the study was to link laboratory and ultrasound characteristics of GD with its pathological features. METHODS: We correlated laboratory and ultrasound data at the time of diagnosis in 28 consecutive GD patients who underwent thyroidectomy with their pathological features, i.e., lymphocytic infiltration and follicular hyperplasia (both classified as mild or severe). RESULTS: Thyroid volume correlated positively with the levels of FT4 (P = 0.002, r2 = 0.42), FT3 (P = 0.011, r2 = 0.22), autoantibodies to thyroglobulin (TgAbs) (P = 0.016, r2 = 0.32), autoantibodies to thyroid peroxidase (TPOAbs) (P = 0.011, r2 = 0.34) and the extent of lymphocytic infiltration (P = 0.006 comparing mild to severe lymphocytic infiltration) but not with the levels of autoantibodies to the thyrotropin receptor (TRAbs) and to follicular hyperplasia. Compared to subjects with mild lymphocytic infiltration, those with severe lymphocytic infiltration showed higher levels of TgAbs (316 vs 0.0 IU/mL, P < 0.0001) and TPOAbs (295 IU/mL vs 14 IU/mL, P < 0.0001) and similar levels of TRAbs (7.5 vs 13 IU/mL, P = 0.68). Compared to patients with mild, those with severe follicular hyperplasia had similar levels of TgAbs (76 vs 30 IU/mL, P = 0.31) and TPOAbs (251 IU/mL vs 45 IU/mL, P = 0.26) but higher levels of TRAbs (39 vs 7.2 IU/mL, P < 0.001). CONCLUSION: In GD, TgAbs and TPOAbs levels correlate with the extent of lymphocytic infiltration, TRAbs levels with the degree of follicular hyperplasia. Thyroid volume, the main factor influencing the severity of hyperthyroidism, is related to lymphocytic infiltration and not to follicular hyperplasia.


Assuntos
Doença de Graves , Humanos , Hiperplasia , Doença de Graves/diagnóstico por imagem , Autoanticorpos , Receptores da Tireotropina
2.
J Intern Med ; 290(1): 116-128, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33259671

RESUMO

AIM: Statin-associated muscle symptoms (SAMS) are a major determinant of poor treatment adherence and/or discontinuation, but a definitive diagnosis of SAMS is challenging. The PROSISA study was an observational retrospective study aimed to assess the prevalence of reported SAMS in a cohort of dyslipidaemic patients. METHODS: Demographic/anamnestic data, biochemical values and occurrence of SAMS were collected by 23 Italian Lipid Clinics. Adjusted logistic regression was performed to estimate odds ratio (OR) and 95% confidence intervals for association between probability of reporting SAMS and several factors. RESULTS: Analyses were carried out on 16 717 statin-treated patients (mean ± SD, age 60.5 ± 12.0 years; 52.1% men). During statin therapy, 9.6% (N = 1599) of patients reported SAMS. Women and physically active subjects were more likely to report SAMS (OR 1.23 [1.10-1.37] and OR 1.35 [1.14-1.60], respectively), whist age ≥ 65 (OR 0.79 [0.70-0.89]), presence of type 2 diabetes mellitus (OR 0.62 [0.51-0.74]), use of concomitant nonstatin lipid-lowering drugs (OR 0.87 [0.76-0.99]), use of high-intensity statins (OR 0.79 [0.69-0.90]) and use of potential interacting drugs (OR 0.63 [0.48-0.84]) were associated with lower probability of reporting SAMS. Amongst patients reporting SAMS, 82.2% underwent dechallenge (treatment interruption) and/or rechallenge (change or restart of statin therapy), with reappearance of muscular symptoms in 38.4% (3.01% of the whole cohort). CONCLUSIONS: The reported prevalence of SAMS was 9.6% of the whole PROSISA cohort, but only a third of patients still reported SAMS after dechallenge/rechallenge. These results emphasize the need for a better management of SAMS to implement a more accurate diagnosis and treatment re-evaluation.


Assuntos
Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Doenças Musculares/induzido quimicamente , Creatina Quinase/sangue , Feminino , Humanos , Itália/epidemiologia , Masculino , Adesão à Medicação , Pessoa de Meia-Idade , Doenças Musculares/enzimologia , Doenças Musculares/epidemiologia , Prevalência , Estudos Retrospectivos
3.
J Chem Phys ; 154(22): 224108, 2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34241203

RESUMO

We devise an efficient scheme to determine vibrational properties from Path Integral Molecular Dynamics (PIMD) simulations. The method is based on zero-time Kubo-transformed correlation functions and captures the anharmonicity of the potential due to both temperature and quantum effects. Using analytical derivations and numerical calculations on toy-model potentials, we show that two different estimators built upon PIMD correlation functions fully characterize the phonon spectra and the anharmonicity strength. The first estimator is associated with the force-force quantum correlators and, in the weak anharmonic regime, yields reliable zero-point motion frequencies and thermodynamic properties of the quantum system. The second one is instead connected to displacement-displacement correlators and accurately probes the lowest-energy phonon excitations, regardless of the anharmonicity strength of the system. We also prove that the use of generalized eigenvalue equations, in place of the standard normal mode equations, leads to a significant speed-up in the PIMD phonon calculations, both in terms of faster convergence rate and smaller time step bias. Within this framework, using ab initio PIMD simulations, we compute phonon dispersions of diamond and of the high-pressure I41/amd phase of atomic hydrogen. We find that in the latter case, the anharmonicity is stronger than previously estimated and yields a sizeable red-shift in the vibrational spectrum of atomic hydrogen.

4.
J Dairy Sci ; 102(6): 5005-5018, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31005329

RESUMO

Thermization is a sub-pasteurization heat treatment of cheese milk (at 57-68°C for 15-30 s) aimed to reduce the number of undesirable microbial contaminants with reduced heat damage to the indigenous milk enzymes. In this work, the effects of milk thermization on the compositional parameters, proteolysis indices, free fatty acid levels, and low molecular weight metabolite profiles of ovine cheese were studied. Cheese samples at different ripening stages and produced in 2 different periods of the year were analyzed. While the effects of milk thermization on cheese macro-compositional parameters and free fatty acid levels were not evident due to the predominant effects of milk seasonality and cheese ripening stage, the gas chromatography-mass spectrometry based metabolomics approach of ovine cheese produced from raw and thermized milk highlighted strong differences at the metabolite level. Discriminant analysis applied to gas chromatography-mass spectrometry data provided an excellent classification model where cheese samples were correctly classified as produced from raw or thermized milk. The metabolites that mostly changed due to the thermization process belonged to the classes of free amino acids and saccharides. Gas chromatography-mass spectrometry-based metabolomics has proven to be a valid tool to study the effect of mild heat treatments on the polar metabolite profile in ovine cheese.


Assuntos
Queijo , Leite/química , Pasteurização , Aminoácidos/química , Animais , Feminino , Cromatografia Gasosa-Espectrometria de Massas/veterinária , Metabolômica , Ovinos
5.
Nutr Metab Cardiovasc Dis ; 27(5): 396-406, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28416099

RESUMO

BACKGROUND AND AIMS: Meta-analyses of randomized control trials investigating the association between incident diabetes and statin use showed an increased risk of new-onset diabetes (NOD) from 9% to 13% associated with statins. However, short follow-up period, unpowered sample size, and lack of pre-specified diagnostic criteria for diabetes detection could be responsible of an underestimation of this risk. We conducted a meta-analysis of published observational studies to evaluate the association between statins use and risk of NOD. METHODS AND RESULTS: PubMed, EMBASE and MEDLINE databases were searched from inception to June 30, 2016 for cohort and case-control studies with risk of NOD in users vs nonusers, on ≥1000 subjects followed-up for ≥1 year. Two review authors assessed study eligibility and risk of bias and undertook data extraction independently. Pooled estimates were calculated by a random-effects model and between-study heterogeneity was tested and measured by I2 index. Furthermore, stratified analyses and the evaluation of publication bias were performed. Finally, the meta-analysis included 20 studies, 18 cohort and 2 case-control studies. Overall, NOD risk was higher in statin users than nonusers (RR 1.44; 95% CI 1.31-1.58). High between-study heterogeneity (I2 = 97%) was found. Estimates for all single statins showed a class effect, from rosuvastatin (RR 1.61; 1.30-1.98) to simvastatin (RR 1.38; 1.19-1.61). CONCLUSIONS: The present meta-analysis confirms and reinforces the evidence of a diabetogenic effect by statins utilization. These observations confirm the need of a rigorous monitoring of patients taking statins, in particular pre-diabetic patients or patients presenting with established risk factors for diabetes.


Assuntos
Glicemia/efeitos dos fármacos , Diabetes Mellitus/induzido quimicamente , Dislipidemias/tratamento farmacológico , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Biomarcadores/sangue , Glicemia/metabolismo , Diabetes Mellitus/sangue , Diabetes Mellitus/diagnóstico , Dislipidemias/sangue , Dislipidemias/diagnóstico , Humanos , Lipídeos/sangue , Estudos Observacionais como Assunto , Razão de Chances , Medição de Risco , Fatores de Risco
6.
J Chem Phys ; 146(3): 034703, 2017 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-28109242

RESUMO

Colloidal magnetic nanoparticles (MNPs) based on a nearly monodisperse iron oxide core and capped by oleic acid have been used as model systems for investigating the superparamagnetic spin dynamics by means of magnetometry measurements and nuclear magnetic resonance (1H NMR) relaxometry. The key magnetic properties (saturation magnetization, coercive field, and frequency dependent "blocking" temperature) of MNPs with different core size (3.5 nm, 8.5 nm, and 17.5 nm), shape (spherical and cubic), and dispersant (hexane and water-based formulation) have been determined. 1H NMR dispersion profiles obtained by measuring the r1 (longitudinal) and r2 (transverse) nuclear relaxivities in the frequency range 0.01-60 MHz confirmed that in all samples the physical mechanisms that drive the nuclear relaxation are the Néel reversal at low temperature and the Curie relaxation at high frequency. The magnetization reversal time at room temperature extracted from the fitting of NMR data falls in the typical range of superparamagnetic systems (10-9-10-10 s). Furthermore, from the distance of minimum approach we could conclude that water molecules do not arrive in close vicinity of the magnetic core. Our findings contribute to elucidate the local spin dynamics mechanisms in colloidal superparamagnetic nanoparticles which are useful in biomedical application as, e.g., contrast agents for magnetic resonance imaging.

7.
J Chem Phys ; 143(24): 244112, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26723656

RESUMO

We introduce an efficient method to construct optimal and system adaptive basis sets for use in electronic structure and quantum Monte Carlo calculations. The method is based on an embedding scheme in which a reference atom is singled out from its environment, while the entire system (atom and environment) is described by a Slater determinant or its antisymmetrized geminal power (AGP) extension. The embedding procedure described here allows for the systematic and consistent contraction of the primitive basis set into geminal embedded orbitals (GEOs), with a dramatic reduction of the number of variational parameters necessary to represent the many-body wave function, for a chosen target accuracy. Within the variational Monte Carlo method, the Slater or AGP part is determined by a variational minimization of the energy of the whole system in presence of a flexible and accurate Jastrow factor, representing most of the dynamical electronic correlation. The resulting GEO basis set opens the way for a fully controlled optimization of many-body wave functions in electronic structure calculation of bulk materials, namely, containing a large number of electrons and atoms. We present applications on the water molecule, the volume collapse transition in cerium, and the high-pressure liquid hydrogen.

8.
Phys Chem Chem Phys ; 16(10): 4843-52, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24469688

RESUMO

We report the detailed structural characterization and magnetic investigation of nanocrystalline zinc ferrite nanoparticles supported on a silica aerogel porous matrix which differ in size (in the range 4-11 nm) and the inversion degree (from 0.4 to 0.2) as compared to bulk zinc ferrite which has a normal spinel structure. The samples were investigated by zero-field-cooling-field-cooling, thermo-remnant DC magnetization measurements, AC magnetization investigation and Mössbauer spectroscopy. The nanocomposites are superparamagnetic at room temperature; the temperature of the superparamagnetic transition in the samples decreases with the particle size and therefore it is mainly determined by the inversion degree rather than by the particle size, which would give an opposite effect on the blocking temperature. The contribution of particle interaction to the magnetic behavior of the nanocomposites decreases significantly in the sample with the largest particle size. The values of the anisotropy constant give evidence that the anisotropy constant decreases upon increasing the particle size of the samples. All these results clearly indicate that, even when dispersed with low concentration in a non-magnetic and highly porous and insulating matrix, the zinc ferrite nanoparticles show a magnetic behavior similar to that displayed when they are unsupported or dispersed in a similar but denser matrix, and with higher loading. The effective anisotropy measured for our samples appears to be systematically higher than that measured for supported zinc ferrite nanoparticles of similar size, indicating that this effect probably occurs as a consequence of the high inversion degree.

9.
Nutr Metab Cardiovasc Dis ; 24(5): 518-23, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24462365

RESUMO

BACKGROUND AND AIM: Pentraxin 3 (PTX3) is an essential component of the humoral arm of innate immunity and, like C-reactive protein, is independently associated with the risk of developing vascular events. Aim of this study was to investigate, in two large population-based surveys, the Bruneck Study and the PLIC Study, whether PTX3 plasma levels predict the progression of common carotid artery intima-media thickness (CCA-IMT), a surrogate marker of atherosclerosis, in the general population during 5 or 6 years of follow-up. RESULTS: In the Bruneck Study, PTX3 plasma levels did not predict a faster progression of CCA-IMT either in the carotid artery or in the femoral artery. This finding was confirmed in the PLIC Study where subjects within the highest tertile of PTX3 did not show an increased progression of CCA-IMT. PTX3 plasma levels were also not associated with the fastest maximum IMT progression. In summary, in more than 2400 subjects from the general population, PTX3 plasma level is neither an independent predictor of progression of subclinical atherosclerosis in different arterial territories, including carotid and femoral arteries nor of incident cardiovascular events. CONCLUSION: These findings support the relevance of investigating the predictive value of PTX3 plasma levels only in specific settings, like overt CVD, heart failure or acute myocardial infarction.


Assuntos
Biomarcadores/sangue , Proteína C-Reativa/metabolismo , Espessura Intima-Media Carotídea , Componente Amiloide P Sérico/metabolismo , Idoso , Idoso de 80 Anos ou mais , Animais , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico por imagem , Artéria Carótida Primitiva/diagnóstico por imagem , Progressão da Doença , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos
10.
Phys Rev Lett ; 110(16): 167002, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23679632

RESUMO

Using angle-resolved photoemission spectroscopy, we study the evolution of the number of carriers in Ba(Fe(1-x)Co(x))(2)As(2) as a function of Co content and temperature. We show that there is a k-dependent energy shift compared to density functional calculations, which is large below 100 K at low Co contents and reduces the volume of hole and electron pockets by a factor 2. This k shift becomes negligible at high Co content and could be due to interband charge or spin fluctuations. We further reveal that the bands shift with temperature, changing significantly the number of carriers they contain (up to 50%). We explain this evolution by thermal excitations of carriers among the narrow bands, possibly combined with a temperature evolution of the k-dependent fluctuations.

11.
Phys Rev Lett ; 109(12): 126408, 2012 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-23005970

RESUMO

We provide a prescription for constructing Hamiltonians representing the low-energy physics of correlated electron materials with dynamically screened Coulomb interactions. The key feature is a renormalization of the hopping and hybridization parameters by the processes that lead to the dynamical screening. The renormalization is shown to be non-negligible for various classes of correlated electron materials. The bandwidth reduction effect is necessary for connecting models to materials behavior and for making quantitative predictions for low-energy properties of solids.

12.
Nutr Metab Cardiovasc Dis ; 22(4): 327-36, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20884190

RESUMO

BACKGROUND AND AIM: To assess cardiovascular risk distribution, distribution of individual low-density lipoprotein (LDL)-cholesterol target and distance of LDL cholesterol from the target in a representative sample of the Italian population. METHODS AND RESULTS: Cross-sectional, population-based study of a representative sample of the Italian adult population, comprising 5458 individuals (from 40 to 79 years of age, both sexes) from general practices in Italy. Of the subjects, 65.2% were in the low-cardiovascular-risk class, whereas 10.5%, 18.3% and 6.0% had moderate, high, and very high cardiovascular risk profiles, respectively; 8.2% of the subjects were treated with statins at enrolment. Of the cohort, 68.3% displayed LDL-cholesterol values below their LDL target, as calculated according to their individual risk profile. Among the 31.7% 'not at target', 42.3% were ≤ 15%, 44.3% were between 15% and 40% and 13.4% were >40% over their LDL target. CONCLUSIONS: About two-thirds of adults in a low-cardiovascular-risk country, such as Italy, have LDL-cholesterol levels 'at target', as defined in current guidelines. Accordingly, the remaining subjects require a lifestyle or pharmacological intervention to reach their target; 24% of the total cohort, in detail, need to be treated with a statin (or to continue the prescribed statin treatment) to reach the proper LDL target. This type of data analysis might help to optimise resource allocation in preventive medicine.


Assuntos
Doenças Cardiovasculares/etiologia , LDL-Colesterol/sangue , Inibidores de Hidroximetilglutaril-CoA Redutases/uso terapêutico , Adulto , Idoso , Doenças Cardiovasculares/sangue , Estudos de Coortes , Estudos Transversais , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade
13.
Sci Rep ; 12(1): 19978, 2022 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-36404312

RESUMO

The eruption of the Hunga-Tonga volcano in the South Pacific Ocean on January 15, 2022, at about 4:15 UTC, generated a violent explosion, which created atmospheric pressure disturbances in the form of Rayleigh-Lamb waves detected all over the globe. Here we discuss the observation of the Hunga-Tonga shock-wave performed at the Ny-Ålesund Research Station on the Spitsbergen island, by the detectors of the PolarquEEEst experiment and their ancillary sensors. Online pressure data as well as the results of dedicated offline analysis are presented and discussed in details. Results include wave arrival times, wave amplitude measurements and wave velocity calculation. We observed five passages of the shock wave with a significance larger than 3 [Formula: see text] and an amplitude up to 1 hPa. The average propagation velocity resulted to be (308 ± 0.6) m/s. Possible effects of the atmospheric pressure variation associated with the shock-wave multiple passages on the cosmic-ray rate at ground level are also investigated. We did not find any significant evidence of this effect.

14.
Neurobiol Dis ; 42(3): 211-20, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21220013

RESUMO

Increasing evidence suggests a role for the immune system in amyotrophic lateral sclerosis (ALS). To determine the extent of the immune activation in ALS we analyzed the expression and cellular distribution of components of innate and adaptive immunity in spinal cord (SC) and motor cortex (MCx) from patients with rapid and slow sporadic ALS and controls. High levels of mRNA and protein of classical complement pathway, C1q and C4, as well as the downstream complement components C3 and C5b-9 were found in all ALS samples. Furthermore, we found higher numbers of activated microglia, reactive astrocytes, dendritic cells (DCs) and CD8(+) T-cells in ALS than in control tissue. Rapid ALS cases had more dendritic cells than slow ALS cases, whereas slow ALS cases had more activated microglia than rapid cases. Our findings demonstrate a persistent and prominent activation of both innate and adaptive immunity in ALS. We propose a complement-driven immune response which may contribute to the progression of the inflammation and ultimately lead to even more motor neuron injury.


Assuntos
Imunidade Adaptativa/imunologia , Esclerose Lateral Amiotrófica/imunologia , Ativação do Complemento/imunologia , Imunidade Inata/imunologia , Adulto , Idoso , Esclerose Lateral Amiotrófica/metabolismo , Análise de Variância , Complexo de Ataque à Membrana do Sistema Complemento/imunologia , Complexo de Ataque à Membrana do Sistema Complemento/metabolismo , Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Hibridização In Situ , Inflamação/imunologia , Inflamação/metabolismo , Masculino , Microglia/imunologia , Microglia/metabolismo , Pessoa de Meia-Idade , Neurônios Motores/imunologia , Neurônios Motores/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Medula Espinal/imunologia , Medula Espinal/metabolismo
15.
Anal Chem ; 83(8): 2877-82, 2011 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-21413785

RESUMO

For imaging with different modalities, labels, which provide contrast for all modalities, are required. Colloidal nanoparticles composed out of an inorganic core and a polymer shell offer progress in this direction. Both, the core and the polymer shell, can be synthesized to be fluorescent, magnetic, or radioactive. When different cores are combined with different polymer shells, different types of particles for dual imaging can be obtained, as for example, fluorescent cores with radioactive polymer shells. Properties and perspectives of such nanoparticles for multimodal imaging are discussed.


Assuntos
Imagem Molecular , Nanopartículas/química , Coloides/síntese química , Coloides/química , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/química , Magnetismo , Polímeros/síntese química , Polímeros/química
16.
J Nanosci Nanotechnol ; 11(8): 6735-46, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22103075

RESUMO

Nanocomposites containing FeCo alloy nanoparticles dispersed in a highly ordered 3D cubic Im3m mesoporous silica (SBA-16) matrix were prepared by a novel, single-step templated-assisted sol-gel technique. Two different approaches were used in the synthesis of nanocomposites; a pure SBA-16 sample was also prepared for comparison. Low-angle X-ray diffraction, transmission electron microscopy and N2 physisorption at 77 K show that after metal loading, calcination at 500 degrees C and reduction in H2 flux at 800 degrees C the nanocomposites retain the cubic mesoporous structure with pore size not very different from the pure matrix. X-ray absorption fine structure (EXAFS) analysis at Fe and Co K-edges demonstrates that the FeCo nanoparticles have the typical bcc structure. The final nanocomposites were tested as catalysts for the production of carbon nanotubes by catalytic chemical vapour deposition and high-resolution TEM shows that good quality multi-walled carbon nanotubes are obtained.

17.
J Nanosci Nanotechnol ; 11(11): 10136-41, 2011 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22413356

RESUMO

Stoichiometric magnetic nanosized ferrites MFe2O4 (M = Mn, Co, Ni) were prepared in form of nearly spherical nanocrystals supported on a highly porous silica aerogel matrix, by a sol-gel procedure. X-ray diffraction and transmission electron microscopy indicate that these materials are made out of non-agglomerated ferrite nanocrystals having size in the 5-10 nm range. Investigation by Mössbauer Spectroscopy was used to gain insights on the superparamagnetic relaxation and on the inversion degree. Magnetic ordering at room temperature varies from superparamagnetic in the NiFe2O4 sample, highly blocked (approximately 70%) in the MnFe2O4 sample and nearly fully blocked in the CoFe2O4 sample. A fitting procedure of the Mössbauer data has been used in order to resolve the spectrum into the tetrahedral and octahedral components; in this way, an inversion degree of 0.68 (very close to bulk values) was obtained for 6 nm silica-supported CoFe2O4 nanocrystals.

18.
Clin Neuropathol ; 30(3): 111-7, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21545774

RESUMO

Post-polio syndrome (PPS) develops in approximately 30% of polio survivors several decades after the acute attack of paralytic poliomyelitis. Some of these patients develop post-poliomyelitis muscular atrophy (PPMA) which is characterized by a slowly progressive muscle weakness. Due to its clinicopathological features, investigators have often studied PPS and PPMA in association with amyotrophic lateral sclerosis (ALS), the underlying hypothesis being an increased risk of developing ALS from a prior acute paralytic poliomyelitis. Various studies, however, have indicated that de novo ALS cases in patients with prior acute paralytic poliomyelitis are rare. Herein, we describe a rare case of a 75-year-old woman who at post-mortem examination presented a combination of a PPS with proven histopathological sporadic ALS features. Furthermore, neuropathology of this case also revealed several other histopathological findings reminiscent of a tauopathy, synucleinopathy and amyloid angiopathy and a large pituitary cyst. To our knowledge, this is the first reported case of PPS with clear pathological hallmarks of sporadic ALS, including ubiquitin-, TDP-43, phosphorylated TDP-43- and p62-positive inclusions, with accompanying features compatible with Alzheimer's and Parkinson's disease.


Assuntos
Esclerose Lateral Amiotrófica/complicações , Encéfalo/patologia , Síndrome Pós-Poliomielite/complicações , Idoso , Esclerose Lateral Amiotrófica/patologia , Neoplasias da Mama/complicações , Carcinoma/complicações , Feminino , Humanos , Síndrome Pós-Poliomielite/patologia
19.
Phys Chem Chem Phys ; 12(19): 5074-83, 2010 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-20379573

RESUMO

The atomic level structure of a series of monodisperse single crystalline nanoparticles with a magnetic core of manganese ferrite was studied using X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) techniques at both the Fe and Mn K-edges, and conventional and high resolution transmission electron microscopy (TEM and HRTEM). In particular, insights on the non-stoichiometry and on the inversion degree of manganese ferrite nanocrystals of different size were obtained by the use of complementary structural and spectroscopic characterization techniques. The inversion degree of the ferrite nanocrystals, i.e. the cation distribution between the octahedral and tetrahedral sites in the spinel structure, was found to be much higher (around 0.6) than the literature values reported for bulk stoichiometric manganese ferrite (around 0.2). The high inversion degree of the nanoparticles is ascribed to the partial oxidation of Mn(2+) to Mn(3+) which was evidenced by XANES, leading to non-stoichiometric manganese ferrite.

20.
Neurosci Lett ; 399(1-2): 51-6, 2006 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-16481104

RESUMO

We have studied the effect of key neurotrophic factors (NTFs) on morphology, levels of the vanilloid receptor-1 (TRPV1) and responses to capsaicin in adult human sensory neurons in vitro. Avulsed dorsal root ganglia (DRG, n = 5) were cultured with or without a combination of nerve growth factor (NGF), glial cell (line)-derived growth factor (GDNF) and neurotrophin3 (NT3) for 5 days. In the absence of NTFs, the diameter of neurons ranged from 20 to 100 microm (mean 42 +/- 4 microm). Adding NTFs caused a significant increase in neuronal sizes, up to 120 microm (mean diameter 62 +/- 5 microm, P < 0.01, t-test), an overall 35% increase of TRPV1-positive neurons (P < 0.003), and notably of large TRPV1-positive neurons > 80 microm (P < 0.05). Responses to capsaicin were significantly enhanced with calcium ratiometry (P < 0.0001). Short duration (1h) exposure of dissociated sensory neurons to NTFs increased numbers of TRPV1-positive neurons, but not of TRPV3, Nav 1.8 and IK1 and the morphological size-distribution remained similar to intact post-mortem DRG neurons. NTFs thus increase size, elevate TRPV1 levels and enhance capsaicin responses in cultured human DRG neurons; these changes may relate to pathophysiology in disease states, and provide an in vitro model to study novel analgesics.


Assuntos
Capsaicina/farmacologia , Gânglios Espinais/citologia , Fatores de Crescimento Neural/metabolismo , Neurônios Aferentes/efeitos dos fármacos , Canais de Cátion TRPV/biossíntese , Adulto , Tamanho Celular , Células Cultivadas , Fator Neurotrófico Derivado de Linhagem de Célula Glial/metabolismo , Humanos , Masculino , Canal de Sódio Disparado por Voltagem NAV1.8 , Fator de Crescimento Neural/metabolismo , Neurônios Aferentes/citologia , Neurônios Aferentes/metabolismo , Neurotrofina 3/metabolismo , Canais de Potássio Cálcio-Ativados/biossíntese , Canais de Sódio/biossíntese
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