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1.
J Prev Alzheimers Dis ; 11(2): 414-421, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38374747

RESUMO

In vivo Alzheimer's disease diagnosis and staging is traditionally based on clinical features. However, the agreement between clinical and pathological Alzheimer's disease diagnosis, whose diagnosis assessment includes amyloid and Braak histopathological tau staging, is not completely convergent. The development of positron emission tomography (PET) tracers targeting neurofibrillary tangles offers prospects for advancing the staging of Alzheimer's disease from both biological and clinical perspectives. Recent advances in radiochemistry made it possible to apply the postmortem Braak staging framework to tau-PET images obtained in vivo. Here, our aim is to provide a narrative review of the current literature on the relationship between Alzheimer's disease clinical features and the PET-based Braak staging framework. Overall, the available studies support the stepwise increase in disease severity following the advance of PET-based Braak stages, with later stages being associated with worse cognitive and clinical symptoms. In line with this, there is a trend for unimpaired cognition, mild cognitive impairment, and Alzheimer's disease dementia to be compatible with early, intermediate, and late patterns of tau deposition based on PET-based Braak stages. Moreover, neuropsychiatric symptom severity seems to be linked to the extent of tau-PET signal across Braak areas. In sum, this framework seems to correspond well with the clinical progression of Alzheimer's disease, which is an indication of its potential utility in research and clinical practice, especially for detecting preclinical tau levels in individuals without symptoms. However, further research is needed to improve the generalizability of these findings and to better understand the applications of this staging framework.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Doença de Alzheimer/diagnóstico por imagem , Doença de Alzheimer/patologia , Proteínas tau , Emaranhados Neurofibrilares/patologia , Tomografia por Emissão de Pósitrons/métodos , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/patologia
2.
Chaos ; 33(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37934182

RESUMO

We propose a numerical approach to study mesoscopic fluctuations in quantum dots with chiral symmetry. Our method involves applying the random-hopping model to a tight-binding Hamiltonian, allowing us to calculate the conductance and shot-noise power distributions for systems belonging to the three chiral symmetry classes of random matrix theory. Furthermore, we demonstrate that the spectral fluctuations of quantum dots belonging to the Wigner-Dyson symmetry classes of random matrix theory can be obtained by applying the random-hopping model to a scattering region that was originally integrable, thus bypassing the need to use the boundaries of chaotic billiards.

4.
Phys Rev E ; 108(2-1): 024140, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37723817

RESUMO

We investigate the critical behavior of the two-dimensional spin-1 Baxter-Wu model in the presence of a crystal-field coupling Δ with the goal of determining the universality class of transitions along the second-order part of the transition line as one approaches the putative location of the multicritical point. We employ extensive Monte Carlo simulations using two different methodologies: (i) a study of the zeros of the energy probability distribution, closely related to the Fisher zeros of the partition function, and (ii) the well-established multicanonical approach employed to study the probability distribution of the crystal-field energy. A detailed finite-size scaling analysis in the regime of second-order phase transitions in the (Δ,T) phase diagram supports previous claims that the transition belongs to the universality class of the four-state Potts model. For positive values of Δ, we observe the presence of strong finite-size effects, indicative of crossover effects due to the proximity of the first-order part of the transition line. Finally, we demonstrate how a combination of cluster and heat-bath updates allows one to equilibrate larger systems, and we demonstrate the potential of this approach for resolving the ambiguities observed in the regime of Δ≳0.

5.
Braz J Biol ; 83: e271785, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37610945

RESUMO

Ortho-eugenol is a synthetic derivative from eugenol, the major compound of clove essential oil, which has demonstrated antidepressant and antinociceptive effects in pioneering studies. Additionally, its effects appear to be dependent on the noradrenergic and dopaminergic systems. Depression and anxiety disorders are known to share a great overlap in their pathophysiology, and many drugs are effective in the treatment of both diseases. Furthermore, high levels of anxiety are related to working memory deficits and increased oxidative stress. Thus, in this study we investigated the effects of acute treatment of ortho-eugenol, at 50, 75 and 100 mg/kg, on anxiety, working memory and oxidative stress in male Swiss mice. Our results show that the 100 mg/kg dose increased the number of head-dips and reduced the latency in the hole-board test. The 50 mg/kg dose reduced malondialdehyde levels in the prefrontal cortex and the number of Y-maze entries compared to the MK-801-induced hyperlocomotion group. All doses reduced nitrite levels in the hippocampus. It was also possible to assess a statistical correlation between the reduction of oxidative stress and hyperlocomotion after the administration of ortho-eugenol. However, acute treatment was not able to prevent working memory deficits. Therefore, the present study shows that ortho-eugenol has an anxiolytic and antioxidant effect, and was able to prevent substance-induced hyperlocomotion. Our results contribute to the elucidation of the pharmacological profile of ortho-eugenol, as well as to direct further studies that seek to investigate its possible clinical applications.


Assuntos
Eugenol , Memória de Curto Prazo , Masculino , Animais , Camundongos , Eugenol/farmacologia , Eugenol/uso terapêutico , Ansiedade/tratamento farmacológico , Transtornos de Ansiedade , Estresse Oxidativo , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Óleo de Cravo
6.
J Mater Cycles Waste Manag ; : 1-17, 2023 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-37360946

RESUMO

Construction and demolition waste (CDW) is an environmental problem that affects all regions of the world. Particularly in the Brazilian Amazon Forest region, the volume of CDW generated almost doubled between 2007 and 2019. Indeed, despite Brazil having environmental regulations for waste management, these have been insufficient to solve the environmental problem because there is no CDW reverse supply chain (RSC) properly developed in the Amazon region. Previous studies have proposed a conceptual model of a CDW RSC but have hitherto failed to apply them against real world practice. This paper, therefore, attempts to test existing conceptual models that describe a CDW RSC against real industry practice prior to developing an applied model of a CDW RSC for the Brazilian Amazon. To modify the conceptual model for CDW RSC, qualitative data through 15 semi-structured interviews with five different types of stakeholders of the Amazonian CDW RSC were collected and analyzed using qualitative content analysis methods using NVivo software. The proposed applied model includes present and future reverse logistics (RL) practices, and strategies and tasks necessary for the implementation of a CDW RSC in the city of Belém of Pará, in the Brazilian Amazon. Findings reveal that several overlooked problems, particularly the limitations of the existing legal framework in Brazil, are not enough to promote a robust CDW RSC. This is perhaps the first study to examine CDW RSC in the Amazonian rainforest. Arguments provided in this study highlight the necessity for an Amazonian CDW RSC that must be promoted and regulated by the government. This can be addressed by the utilizing public-private partnership (PPP) for developing a CDW RSC.

7.
J Prev Alzheimers Dis ; 10(3): 401-417, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37357281

RESUMO

In the past years, neuroinflammation has been widely investigated in Alzheimer's disease (AD). Evidence from animal, in vivo and post-mortem studies has shown that inflammatory changes are a common feature of the disease, apparently happening in response to amyloid-beta and tau accumulation. Progress in imaging and fluid biomarkers now allows for identifying surrogate markers of neuroinflammation in living individuals, which may offer unprecedented opportunities to better understand AD pathogenesis and progression. In this context, inflammatory mediators and glial proteins (mainly derived from microglial cells and astrocytes) seem to be the most promising biomarkers. Here, we discuss the biological basis of neuroinflammation in AD, revise the proposed neuroinflammation biomarkers, describe what we have learned from anti-inflammatory drug trials, and critically discuss the potential addition of these biomarkers in the AT(N) framework.


Assuntos
Doença de Alzheimer , Animais , Humanos , Doença de Alzheimer/metabolismo , Doenças Neuroinflamatórias , Peptídeos beta-Amiloides/metabolismo , Microglia/metabolismo , Microglia/patologia , Biomarcadores/metabolismo
8.
Rev. neurol. (Ed. impr.) ; 76(S01)Ene-Jun. 2023. tab
Artigo em Espanhol | IBECS | ID: ibc-219308

RESUMO

Introducción: La esclerosis múltiple es una enfermedad neurológica crónica con numerosos tratamientos modificadores de la enfermedad disponibles, incluido el dimetilfumarato (DMF), una terapia de primera línea para la esclerosis múltiple remitente-recurrente. Aunque las tasas de discontinuación del DMF suelen ser bajas en los ensayos clínicos, la falta de adhesión al tratamiento se asocia con peores resultados clínicos. Evaluar la adhesión en el mundo real y los factores predictivos es fundamental para mejorar los resultados clínicos de los pacientes. Este estudio evaluó la adhesión al DMF durante 24 meses en una cohorte de pacientes tratados en un centro portugués. Pacientes y métodos: Estudio prospectivo no intervencionista, de un solo centro, con un seguimiento de 24 meses. El estudio incluyó a pacientes adultos con esclerosis múltiple remitente-recurrente tratados con DMF en la práctica clínica habitual. Se calculó la adhesión al DMF y se consideró que los pacientes eran adherentes si el valor estaba por encima del 80%. Se compararon variables clínicas y sociodemográficas entre grupos. Resultados: De los 80 pacientes incluidos, el 74% eran mujeres, con una edad media de 39 años y una edad media en el momento del diagnóstico de 32 años. Veintiséis pacientes no habían recibido tratamiento previo. La adhesión varió entre el 93, el 82 y el 87,5% a los 6, 12 y 24 meses, respectivamente. No se encontraron diferencias entre los pacientes que no habían recibido tratamiento previo y los que sí lo habían recibido. Conclusión: Este análisis en el mundo real mostró una adhesión significativa al tratamiento con DMF durante dos años por parte de los pacientes portugueses. No obstante, estos resultados deben interpretarse considerando los cambios sustanciales en las consultas externas y las diversas restricciones periódicas debidas a la pandemia de COVID-19, que afectaron en gran medida al seguimiento de los pacientes y a la recopilación de datos.(AU)


Introduction: Multiple sclerosis is a chronic neurological disease with numerous disease-modifying treatments available, including dimethyl fumarate (DMF), a first-line therapy for relapsing-remitting multiple sclerosis. Although rates of discontinuation of DMF are generally low in clinical trials, non-adherence to treatment is associated with poorer clinical outcomes. Assessing real-world adherence and predictive factors is critical to be able to improve clinical outcomes for patients. This study evaluated adherence to DMF over 24 months in a cohort of patients treated in a Portuguese healthcare centre. Patients and methods: A prospective, non-interventional, single-centre study with 24 months’ follow-up was conducted. The study included adult patients with relapsing-remitting multiple sclerosis treated with DMF in routine clinical practice. Adherence to DMF was calculated and patients were considered to have adhered if the value was above 80%. Clinical and socio-demographic variables were compared between groups. Results: Of the 80 patients included, 74% were women, with a mean age of 39 years and a mean age of 32 years at diagnosis. Twenty-six patients had not received any previous treatment. Adherence varied between 93, 82 and 87.5% at 6, 12 and 24 months, respectively. No differences were found between patients who had not received any prior treatment and those who had been treated. Conclusion: This real-world analysis showed significant adherence to DMF treatment by Portuguese patients over a period of two years. However, these results must be interpreted in the light of the substantial changes in outpatient consultations and the various periodic restrictions due to the COVID-19 pandemic, which had an important effect on patient follow-up and data collection.(AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Esclerose Múltipla Recidivante-Remitente , Fumarato de Dimetilo , Doenças do Sistema Nervoso , Estudos Prospectivos , Neurologia , Portugal
9.
Rev Neurol ; 76(s01): S1-S6, 2023 01 31.
Artigo em Espanhol | MEDLINE | ID: mdl-36683265

RESUMO

INTRODUCTION: Multiple sclerosis is a chronic neurological disease with numerous disease-modifying treatments available, including dimethyl fumarate (DMF), a first-line therapy for relapsing-remitting multiple sclerosis. Although rates of discontinuation of DMF are generally low in clinical trials, non-adherence to treatment is associated with poorer clinical outcomes. Assessing real-world adherence and predictive factors is critical to be able to improve clinical outcomes for patients. This study evaluated adherence to DMF over 24 months in a cohort of patients treated in a Portuguese healthcare centre. PATIENTS AND METHODS: A prospective, non-interventional, single-centre study with 24 months' follow-up was conducted. The study included adult patients with relapsing-remitting multiple sclerosis treated with DMF in routine clinical practice. Adherence to DMF was calculated and patients were considered to have adhered if the value was above 80%. Clinical and socio-demographic variables were compared between groups. RESULTS: Of the 80 patients included, 74% were women, with a mean age of 39 years and a mean age of 32 years at diagnosis. Twenty-six patients had not received any previous treatment. Adherence varied between 93, 82 and 87.5% at 6, 12 and 24 months, respectively. No differences were found between patients who had not received any prior treatment and those who had been treated. CONCLUSION: This real-world analysis showed significant adherence to DMF treatment by Portuguese patients over a period of two years. However, these results must be interpreted in the light of the substantial changes in outpatient consultations and the various periodic restrictions due to the COVID-19 pandemic, which had an important effect on patient follow-up and data collection.


TITLE: Adhesión real al dimetilfumarato en pacientes con esclerosis múltiple remitente-recurrente.Introducción. La esclerosis múltiple es una enfermedad neurológica crónica con numerosos tratamientos modificadores de la enfermedad disponibles, incluido el dimetilfumarato (DMF), una terapia de primera línea para la esclerosis múltiple remitente-recurrente. Aunque las tasas de discontinuación del DMF suelen ser bajas en los ensayos clínicos, la falta de adhesión al tratamiento se asocia con peores resultados clínicos. Evaluar la adhesión en el mundo real y los factores predictivos es fundamental para mejorar los resultados clínicos de los pacientes. Este estudio evaluó la adhesión al DMF durante 24 meses en una cohorte de pacientes tratados en un centro portugués. Pacientes y métodos. Estudio prospectivo no intervencionista, de un solo centro, con un seguimiento de 24 meses. El estudio incluyó a pacientes adultos con esclerosis múltiple remitente-recurrente tratados con DMF en la práctica clínica habitual. Se calculó la adhesión al DMF y se consideró que los pacientes eran adherentes si el valor estaba por encima del 80%. Se compararon variables clínicas y sociodemográficas entre grupos. Resultados. De los 80 pacientes incluidos, el 74% eran mujeres, con una edad media de 39 años y una edad media en el momento del diagnóstico de 32 años. Veintiséis pacientes no habían recibido tratamiento previo. La adhesión varió entre el 93, el 82 y el 87,5% a los 6, 12 y 24 meses, respectivamente. No se encontraron diferencias entre los pacientes que no habían recibido tratamiento previo y los que sí lo habían recibido. Conclusión. Este análisis en el mundo real mostró una adhesión significativa al tratamiento con DMF durante dos años por parte de los pacientes portugueses. No obstante, estos resultados deben interpretarse considerando los cambios sustanciales en las consultas externas y las diversas restricciones periódicas debidas a la pandemia de COVID-19, que afectaron en gran medida al seguimiento de los pacientes y a la recopilación de datos.


Assuntos
COVID-19 , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Adulto , Humanos , Feminino , Masculino , Fumarato de Dimetilo/uso terapêutico , Fumarato de Dimetilo/efeitos adversos , Esclerose Múltipla Recidivante-Remitente/tratamento farmacológico , Imunossupressores/uso terapêutico , Imunossupressores/efeitos adversos , Esclerose Múltipla/tratamento farmacológico , Pandemias , Estudos Prospectivos
10.
Chem Biodivers ; 20(2): e202200888, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36703594

RESUMO

Aiming of self-sustainable production, the search for biodegradable and biocompatible materials has brought with it the need to know the physicochemical and dielectric characteristics of polysaccharide-based composite structures, which can be used as important and promising raw materials for biotechnology and electronic industries. Galactomannans are polysaccharides, extracted from seeds and microbiological sources, consisting of mannose and galactose. In this context, this work aimed to extract, purify and characterize by XRD, FTIR and impedance spectroscopy galactomannan obtained from seeds of Adenanthera pavonina L. The purification process was made with ethyl alcohol at concentrations of 70, 80 and 90 %. Polymeric films were prepared by solvent slow evaporation at low temperatures. XRD measurements revealed that Galactomannan from Adenanthera pavonina L., after purification, has a semi-crystalline structure due to the identification of two peaks the first between 5.849° and 6.118° and the second between 20.011° and 20.247°. FTIR spectra showed the functional groups associated with monosaccharides of the galactomannan from Adenanthera pavonina L. seeds, as well as the typical polysaccharide bands and peaks, confirmed by literature data. The impedance results give an increment on the state-of-the-art of this biomaterial by showing the existence of dielectric relaxations, independent of the degree of purification, using the dielectric modulus formalism. The permittivity analysis reveals the presence of water in the structure of the film, whose dipoles contribute to the relatively high value of the dielectric constant. From the results obtained, it can be concluded that purified galactomannan has the potential for possible applications in the electronics industry as a green and eco-friendly dielectric material.


Assuntos
Fabaceae , Mananas , Mananas/análise , Mananas/química , Fabaceae/química , Polissacarídeos/química , Galactose , Sementes/química , Materiais Biocompatíveis
11.
Light Sci Appl ; 11(1): 104, 2022 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-35449144

RESUMO

A photonic connection between turbulence and spin glasses has been recently established both theoretically and experimentally using a random fiber laser as a photonic platform. Besides unveiling this interplay, it links the works of two 2021 Nobel laureates in Physics.

12.
Phys Rev E ; 104(5-1): 054143, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34942778

RESUMO

Lévy flight superdiffusion consists of random walks characterized by very long jumps that dominate the transport. However, the finite size of real samples introduces truncation of long jumps and modifies the transport properties. We measure typical Levy flight parameters for photon diffusion in atomic vapor characterized by a Voigt absorption profile. We observe the change of Lévy parameter as a function of truncation length. We associate this variation with size-dependent contributions from different spectral regions of the emission profile with the Doppler core dominating the transport for thin samples and Lorentz wings for thick samples. Monte Carlo simulations are implemented to support the interpretation of results.

13.
Phys Rev E ; 104(5-1): 054129, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34942834

RESUMO

We perform a multifractal detrended fluctuation analysis of the magnetoconductance data of two standard types of mesoscopic systems: a disordered nanowire and a ballistic chaotic billiard, with two different lattice structures. We observe in all cases that multifractality is generally present and that it becomes stronger in the quantum regime of conduction, i.e., when the number of open scattering channels is small. We argue that this behavior originates from correlations induced by the magnetic field, which can be characterized through the distribution of conductance increments in the corresponding "stochastic time series," with the magnetic field playing the role of a fictitious time. More specifically, we show that the distributions of conductance increments are well fitted by q Gaussians and that the value of the parameter q is a useful quantitative measure of multifractality in magnetoconductance fluctuations.

15.
Bone Marrow Transplant ; 56(12): 3042-3048, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34548627

RESUMO

Haploidentical hematopoietic-cell transplantation using post-transplant cyclophosphamide(Haplo-PTCy) is a feasible procedure in children with haematologic malignancies. However, data of a large series of children with acute leukaemia(AL) in this setting is missing. We analysed 144 AL Haplo-PTCy paediatric recipients; median age was 10 years. Patients had acute lymphoblastic(ALL; n = 86) or myeloblastic leukaemia(AML; n = 58) and were transplanted in remission(CR1: n = 40; CR2: n = 57; CR3+: n = 27) or relapse (n = 20). Bone marrow was the graft source in 57%; donors were father (54%), mother (35%), or sibling (11%). Myeloablative conditioning was used in 87%. Median follow-up was 31 months. At day +100, cumulative incidence (CI) of neutrophil recovery and acute GVHD (II-IV) were 94% and 40%, respectively. At 2-years, CI of chronic GVHD and relapse, were 31%, 40%, and estimated 2-year overall survival (OS), leukaemia-free survival (LFS) and graft-versus-host-relapse-free survival (GRFS) were 52%, 44% and 34% respectively. For patients transplanted in remission, positive measurable residual disease (MRD) prior to transplant was associated with decreased LFS (p = 0.05) and GRFS (p = 0.003) and increased risk of relapse (p = 0.02). Mother donor was associated with increased risk of chronic GVHD (p = 0.001), decreased OS (p = 0.03) and GRFS (p = 0.004). Use of PBSC was associated with increased risk of chronic GVHD (p = 0.04). In conclusion, achieving MRD negativity pre-transplant, avoiding use of mother donors and PBSC as graft source may improve outcomes of Haplo-PTCy in children with AL.


Assuntos
Doença Enxerto-Hospedeiro , Transplante de Células-Tronco Hematopoéticas , Leucemia Mieloide Aguda , Células-Tronco de Sangue Periférico , Criança , Ciclofosfamida/uso terapêutico , Feminino , Doença Enxerto-Hospedeiro/etiologia , Transplante de Células-Tronco Hematopoéticas/métodos , Humanos , Leucemia Mieloide Aguda/complicações , Mães , Recidiva Local de Neoplasia , Estudos Retrospectivos , Condicionamento Pré-Transplante/métodos , Transplante Haploidêntico/efeitos adversos
16.
Arq. bras. med. vet. zootec. (Online) ; 73(4): 893-901, Jul.-Aug. 2021. tab, graf, mapas, ilus
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1285264

RESUMO

Survival and growth of the native oyster Crassostrea gasar along the juvenile and adult phases were evaluated in three different stocking densities [low (D), medium (2D) and high (3D)] and in two grow-out systems (fixed and floating system). The fixed system consisted of a rack made with PVC, fixed from the bottom with wood sticks. The floating system consisted of floating bags suspended by a rack made with PVC and maintained submerged from the seawater surface by eight floats. Survival and shell height of oysters cultured after 30, 60 and 90 days were registered in each phase and in each grow-out system. Results showed that the grow-out system did not affect survival and growth of C. gasar in the juvenile and adult phases. The tested densities affected the survival of oysters cultured over time in both phases but did not affect oyster growth. At times analyzed, it was observed positive growth in juvenile oysters grow after 90 days of culture. However, in the adult phase, no growth was observed after 90 days of culture. Oyster yield was higher in the density 3D, in both juvenile and adult phases. These findings contributed to the development of the oyster C. gasar culture.(AU)


A sobrevivência e o crescimento da ostra nativa Crassostrea gasar nas fases juvenil e adulta foram avaliados sob três diferentes densidades de estocagem [baixa (D), média (2D) e alta (3D)] e dois sistemas de engorda (fixo e flutuante). O sistema fixo consistiu em uma mesa de PVC, fixada na parte inferior com varas de madeira. O sistema flutuante consistiu em travesseiros flutuantes suspensos por uma mesa de PVC e mantidas submersas da superfície da água do mar por oito flutuadores. Registraram-se sobrevivência e altura da concha de ostras cultivadas após 30, 60 e 90 dias, em cada fase (juvenil e adulta) e em cada sistema (fixo e flutuante). Os resultados mostraram que o sistema de engorda não afetou a sobrevivência e o crescimento de C. gasar nas fases juvenil e adulta. As densidades testadas afetaram a sobrevivência das ostras ao longo do tempo, em ambas as fases, mas não afetaram o crescimento em altura. Nos tempos analisados, ostras juvenis apresentaram crescimento após 90 dias de cultivo. Porém, na fase adulta, não foi observado crescimento após 90 dias de cultivo. A produção de ostras, foi maior na densidade 3D, nas fases juvenil e adulta. Os presentes achados contribuíram para o desenvolvimento do cultivo da ostra C. gasar.(AU)


Assuntos
Animais , Aquicultura/métodos , Crassostrea/crescimento & desenvolvimento , Sobrevida , Clima Tropical
17.
Odontol. sanmarquina (Impr.) ; 24(2): 5-11, abr.-jun. 2021.
Artigo em Espanhol | LILACS-Express | LILACS | ID: biblio-1178061

RESUMO

Objetivo. El objetivo de este estudio fue evaluar la adaptación marginal de coronas de disilicato de litio obtenidas mediante técnicas de escaneo (CAD/CAM), antes y des- pués de la cristalización, a través de análisis in vitro con microscopía confocal (MC). Métodos. Fueron confeccionadas 16 réplicas en poliuretano a partir de la pieza 1.4, de modelo typodont, tallada para corona total. Las réplicas fueron divididas en dos gru- pos, de acuerdo a la técnica de escaneo: Técnica Indirecta (Grupo IND, n=08), donde modelos de yeso fueron escaneados con escáner de laboratorio (inEos X5, Sirona Den- tal Systems) y Técnica Directa (Grupo DIR, n=08), donde modelos typodont fueron escaneados con escáner intraoral (CEREC BlueCam, Sirona Dental Systems). A seguir, se fresaron (inLab MC XL, Sirona Dental Systems) coronas en disilicato de litio (IPS e.max CAD, Ivoclar Vivadent) y se adaptaron a las réplicas. Se evaluó la adaptación marginal con análisis de MC en dos momentos, antes y después de la cristalización del disilicato de litio. Los datos fueron analizados con la prueba de Mann-Whitney, t de Student y Wilcoxon (α= 0,05). Resultados. Hubo una diferencia estadísticamente significativa en la adaptación marginal horizontal entre los grupos IND y DIR después de la cristalización (p=0,05). En el grupo IND, la comparación de la adaptación mar- ginal vertical antes y después de la cristalización mostró una diferencia estadísticamente significativa (p=0,038). Conclusiones. Las coronas de disilicato de litio obtenidas me- diante escaneo directo (CAD/CAM) presentaron menor desajuste marginal vertical. La etapa de cristalización afectó la adaptación marginal de las coronas.


Objective. This study aimed to evaluate lithium disilicate marginal adaption on crowns by scanning techniques (CAD/CAM), before and after crystallization, through confocal microscopy (CM) in vitro analysis. Methods. Sixteen polyurethane replicas were per- formed from tooth 1.4, of a typodont model, prepared for a full crown. The replicas were divided into two groups, according to the scanning technique: Indirect Technique (Group IND, n=08), where dental stone models were scanned with a laboratory scanner (inEos X5, Sirona Dental Systems) and Direct Technique (Group DIR, n=08), where typodont models were scanned with an intraoral scanner (CEREC BlueCam, Sirona Dental Systems). Then, the lithium disilicate crowns (IPS e.max CAD, Ivoclar Vivadent) were milled (inLab MC XL, Sirona Dental Systems) and adapted to the replicas. Margin- al adaptation was evaluated with CM analysis before and after lithium disilicate crystalli- zation. Data were analyzed with the Mann-Whitney, t test, and Wilconxon test (α=0.05). Results. There was a statistically significant difference in horizontal marginal adaptation between IND and DIR groups after crystallization (p=0.05). In IND group, the compar- ison of vertical marginal adaptation before and after crystallization showed a statistically significant difference (p=0.038). Conclusions. Lithium disilicate crowns obtained by direct scanning technique (CAD/CAD) showed less vertical marginal maladjustment. The crystallization stage affected the crown's marginal adaptation.

18.
Braz J Biol ; 81(2): 246-250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32428096

RESUMO

AIM: This study aimed to verify the correlation between murine measurements and retroperitoneal adipose tissue in rats exposed to the high-fat diet. Material and methods: Wistar male adult rats, descendants of mothers who consumed a high-fat diet during pregnancy and lactation and fed the same diet after weaning were used. At 60 days of life, body weight, longitudinal axis and waist circumference (WC) were measured. The Body Mass Index (BMI) and the Lee Index were calculated for a posterior analysis of the correlation with the amount of retroperitoneal adipose tissue dissected on the same day. For analysis of the data, the Pearson correlation test was used, considering statistical significance for p <0.05. Results: Body weight had a weak correlation (r= 0.31; p= 0.38) with retroperitoneal adipose tissue. While the longitudinal correlated moderately and negative (r= -0.40; p= 0.25). Abdominal circumference (r= 0.62; p= 0.05), body mass index (r= 0.61; p= 0.03) and Lee (r= 0.69; p= 0.03) correlated moderately and positively with adipose tissue. Conclusion: Among the measured murine measurements, weight and longitudinal axis were not good indicators to represent accumulation of retroperitoneal adipose tissue in rats. However, Lee's index seems to be the best murine marker to diagnose the accumulation of retroperitoneal fat. BMI, CA and Lee index were murine parameters with higher correlation.


Assuntos
Dieta Hiperlipídica , Gordura Intra-Abdominal , Animais , Índice de Massa Corporal , Feminino , Masculino , Camundongos , Gravidez , Ratos , Ratos Wistar , Circunferência da Cintura
19.
HIV Med ; 22(3): 212-217, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33012065

RESUMO

OBJECTIVES: We aimed to characterize neurocognitive impairment (NI) in an HIV-2 population using an observational cross-sectional study in four Portuguese hospitals. METHODS: Adult HIV-2-infected patients were included. Montreal Cognitive Assessment Test (MoCA) and International HIV Dementia Scale (IHDS) scales were applied for screening of NI. Patient Health Questionnaire-9 (PHQ-9) and Instrumental Activities of Daily Living (IADL) scales were used for assessment of depression and functionality. A multivariate analysis was performed to assess for risk factors for NI. RESULTS: Eighty-one patients were included, 50.6% of African origin (n = 41) and 49.4% of Portuguese origin (n = 40). The MoCA scale showed alterations in 81.5% of patients (100% of migrants vs. 62.5% of non-migrants, P < 0.001) and the IHDS scale showed alterations in 42%. Both scales were altered simultaneously in 35.8%. Variables independently associated with NI were age [odds ratio (OR) = 0.885] and migrant status (OR = 9.150). CONCLUSIONS: Neurocognitive impairment (both scales altered) was present in 35.8%, which is comparable to what is described for HIV-1. The MoCA performed worse in the migrant population and might not be applicable in this setting.


Assuntos
Complexo AIDS Demência , Disfunção Cognitiva , Infecções por HIV , Atividades Cotidianas , Adulto , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/etiologia , Estudos Transversais , Infecções por HIV/complicações , Infecções por HIV/psicologia , HIV-2 , Humanos , Testes de Estado Mental e Demência , Testes Neuropsicológicos
20.
Braz. j. biol ; 81(2): 246-250, 2021. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1153363

RESUMO

Aim: This study aimed to verify the correlation between murine measurements and retroperitoneal adipose tissue in rats exposed to the high-fat diet. Material and methods: Wistar male adult rats, descendants of mothers who consumed a high-fat diet during pregnancy and lactation and fed the same diet after weaning were used. At 60 days of life, body weight, longitudinal axis and waist circumference (WC) were measured. The Body Mass Index (BMI) and the Lee Index were calculated for a posterior analysis of the correlation with the amount of retroperitoneal adipose tissue dissected on the same day. For analysis of the data, the Pearson correlation test was used, considering statistical significance for p<0.05. Results: Body weight had a weak correlation (r= 0.31; p= 0.38) with retroperitoneal adipose tissue. While the longitudinal correlated moderately and negative (r= -0.40; p= 0.25). Abdominal circumference (r= 0.62; p= 0.05), body mass index (r= 0.61; p= 0.03) and Lee (r= 0.69; p= 0.03) correlated moderately and positively with adipose tissue. Conclusion: Among the measured murine measurements, weight and longitudinal axis were not good indicators to represent accumulation of retroperitoneal adipose tissue in rats. However, Lee's index seems to be the best murine marker to diagnose the accumulation of retroperitoneal fat. BMI, CA and Lee index were murine parameters with higher correlation.


Objetivo: Este estudo teve como objetivo verificar a correlação entre medidas murinométricas e tecido adiposo retroperitoneal em ratos expostos à dieta hiperlipídica. Material e métodos: Foram utilizados ratos Wistar machos adultos, descendentes de mães que consumiram dieta hiperlipídica durante a gestação e lactação e alimentados com a mesma dieta após o desmame. Aos 60 dias de vida, foram medidos o peso corporal, o eixo longitudinal e a circunferência da cintura (CC). O Índice de Massa Corporal (IMC) e o Índice de Lee foram calculados para posterior análise da correlação com a quantidade de tecido adiposo retroperitoneal dissecado no mesmo dia. Para análise dos dados, utilizou se o teste de correlação de Pearson, considerando significância estatística para p<0.05. Resultados: O peso corporal apresentou uma correlação fraca (r= 0,31; p= 0,38) com o tecido adiposo retroperitoneal. Enquanto o longitudinal correlacionou moderadamente e negativo (r= -0,40; p= 0,25). A circunferência abdominal (r = 0,62; p = 0,05), índice de massa corporal (r= 0,61; p= 0,03) e Lee (r= 0,69; p= 0,03) correlacionaram-se moderada e positivamente com o tecido adiposo. Conclusão: Entre as medidas murinométricas, o peso e o eixo longitudinal não foram bons indicadores para representar o acúmulo de tecido adiposo retroperitoneal em ratos. No entanto, o índice de Lee parece ser o melhor indicador murinométrico para diagnosticar o acúmulo de gordura retroperitoneal. O IMC, índice de Lee e CA foram parâmetros murinométricos com maior correlação.


Assuntos
Animais , Masculino , Ratos , Gordura Intra-Abdominal/anatomia & histologia , Dieta Hiperlipídica/veterinária , Índice de Massa Corporal , Ratos Wistar/anatomia & histologia , Circunferência da Cintura
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