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1.
J Biol Regul Homeost Agents ; 35(2 Suppl. 1): 253-269, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34281323

RESUMO

The diabetes and osteoporotic metabolic diseases are characterized by a wide prevalence of the population worldwide and correlated to alteration of the bone tissues. Several cofactors could influence the clinical course and the biochemistry of the pathologies such as human microbiome, nutrition characteristics, gut microbiota activity and interactions with vitamin K and D across IGF/GH and TP53 signaling pathways and the glucose/energy as mechanism for bone tissue health. Moreover, also the calories and sugar consumption seem to be correlated to an increased inflammatory state with several consequences for hematopoiesis and host tissues response. The aim of the present literature review was to highlight the role of osteoporotic diseases and diabetes type 2 link for the bone metabolism. The literature cases showed that a correlation between bone-gut-kidney-heart-CNS-Immunity crosstalk seems to be linked with bone metabolism and health regulation. Moreover, also the aging process could represent a valuable co-factor for the sustaining of the metabolic disorders upon a multi-systemic level.


Assuntos
Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Doenças Metabólicas , Osso e Ossos , Hematopoese , Humanos
2.
Clin Chem Lab Med ; 58(2): 251-260, 2020 01 28.
Artigo em Inglês | MEDLINE | ID: mdl-31539347

RESUMO

Background Our laboratory obtained the ISO 15189 accreditation for the plasmatic HIV-1, HBV and HCV viral load (VL) using the m2000 RealTime™ system, which was recently changed for the platform Panther®. Here, we discuss a strategy for performing method validation/verification very quickly. Methods We performed the mandatory (repeatability, internal quality assessment [IQA], measurement uncertainty [MU]) and optional technical verifications for CE/IVD assays using the flexible scope range A. We also performed the mandatory assays for the validation of HIV-1 VL in the cerebrospinal fluid (CSF) using the flexible scope range B. The change was checked by following up on the turnaround time (TAT). Results The coefficient of variation (CV%) for repeatability and IQA complied with the limit of 0.25 log. The MU results ranged from 0.04 to 0.25 log copies or IU/mL. The comparisons of methods showed excellent correlations (R2 = 0.96 for the three parameters) but a delayed centrifugation on HCV VL showed variations of up to 2 log IU/mL. An excellent linearity for HIV-1 in the CSF was obtained from 1.5 to 5 log copies/mL with R2 = 0.99. The TAT increased (84%-98%) in routine usage. Conclusions The three Aptima assays are well suited for routine laboratory use and can be integrated within less than 2 weeks in accordance with flexible scope range A. Our data allows us to confidently perform HIV-1 VL in CSF following flexible scope range B. Finally, we provide an organizational guide for flexible scope management in molecular virology within a short time frame.


Assuntos
HIV-1/genética , Hepacivirus/genética , Vírus da Hepatite B/genética , Técnicas de Diagnóstico Molecular/normas , RNA Viral/normas , Infecções Transmitidas por Sangue/diagnóstico , Infecções Transmitidas por Sangue/virologia , HIV-1/isolamento & purificação , Hepacivirus/isolamento & purificação , Vírus da Hepatite B/isolamento & purificação , Humanos , Técnicas de Diagnóstico Molecular/métodos , RNA Viral/sangue , RNA Viral/líquido cefalorraquidiano , Kit de Reagentes para Diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , Reprodutibilidade dos Testes , Carga Viral , Produtos do Gene pol do Vírus da Imunodeficiência Humana/genética
3.
Nanotechnology ; 22(14): 145302, 2011 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-21346301

RESUMO

A direct process for manufacturing polymer carbon nanotube (CNT)-based composite yarns is reported. The new approach is based on a modified dry spinning method of CNT yarn and gives a high alignment of the CNT bundle structure in yarns. The aligned CNT structure was combined with a polymer resin and, after being stressed through the spinning process, the resin was cured and polymerized, with the CNT structure acting as reinforcement in the composite. Thus the present method obviates the need for special and complex treatments to align and disperse CNTs in a polymer matrix. The new process allows us to produce a polymer/CNT composite with properties that may satisfy various engineering specifications. The structure of the yarn was investigated using scanning electron microscopy coupled with a focused-ion-beam system. The tensile behavior was characterized using a dynamic mechanical analyzer. Fourier transform infrared spectrometry was also used to chemically analyze the presence of polymer on the composites. The process allows development of polymer/CNT-based composites with different mechanical properties suitable for a range of applications by using various resins.


Assuntos
Nanocompostos/química , Nanotecnologia/instrumentação , Nanotecnologia/métodos , Nanotubos de Carbono/química , Polímeros/química , Módulo de Elasticidade , Elastômeros/química , Microscopia Eletrônica de Varredura , Nanocompostos/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Polímeros/síntese química , Poliuretanos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Estresse Mecânico , Propriedades de Superfície , Temperatura , Resistência à Tração
4.
Adv Colloid Interface Sci ; 105: 3-62, 2003 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-12969641

RESUMO

A review of spontaneous rupture in thin films with tangentially immobile interfaces is presented that emphasizes the theoretical developments of film drainage and corrugation growth through the linearization of lubrication theory in a cylindrical geometry. Spontaneous rupture occurs when corrugations from adjacent interfaces become unstable and grow to a critical thickness. A corrugated interface is composed of a number of waveforms and each waveform becomes unstable at a unique transition thickness. The onset of instability occurs at the maximum transition thickness, and it is shown that only upper and lower bounds of this thickness can be predicted from linear stability analysis. The upper bound is equivalent to the Frenkel criterion and is obtained from the zeroth order approximation of the H3 term in the evolution equation. This criterion is determined solely by the film radius, interfacial tension and Hamaker constant. The lower bound is obtained from the first order approximation of the H3 term in the evolution equation and is dependent on the film thinning velocity. A semi-empirical equation, referred to as the MTR equation, is obtained by combining the drainage theory of Manev et al. [J. Dispersion Sci. Technol., 18 (1997) 769] and the experimental measurements of Radoev et al. [J. Colloid Interface Sci. 95 (1983) 254] and is shown to provide accurate predictions of film thinning velocity near the critical thickness of rupture. The MTR equation permits the prediction of the lower bound of the maximum transition thickness based entirely on film radius, Plateau border radius, interfacial tension, temperature and Hamaker constant. The MTR equation extrapolates to Reynolds equation under conditions when the Plateau border pressure is small, which provides a lower bound for the maximum transition thickness that is equivalent to the criterion of Gumerman and Homsy [Chem. Eng. Commun. 2 (1975) 27]. The relative accuracy of either bound is thought to be dependent on the amplitude of the hydrodynamic corrugations, and a semi-empirical correlation is also obtained that permits the amplitude to be calculated as a function of the upper and lower bound of the maximum transition thickness. The relationship between the evolving theoretical developments is demonstrated by three film thickness master curves, which reduce to simple analytical expressions under limiting conditions when the drainage pressure drop is controlled by either the Plateau border capillary pressure or the van der Waals disjoining pressure. The master curves simplify solution of the various theoretical predictions enormously over the entire range of the linear approximation. Finally, it is shown that when the Frenkel criterion is used to assess film stability, recent studies reach conclusions that are contrary to the relevance of spontaneous rupture as a cell-opening mechanism in foams.

5.
Neural Netw ; 14(2): 185-99, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11316233

RESUMO

This paper presents mesh-free procedures for solving linear differential equations (ODEs and elliptic PDEs) based on multiquadric (MQ) radial basis function networks (RBFNs). Based on our study of approximation of function and its derivatives using RBFNs that was reported in an earlier paper (Mai-Duy, N. & Tran-Cong, T. (1999). Approximation of function and its derivatives using radial basis function networks. Neural networks, submitted), new RBFN approximation procedures are developed in this paper for solving DEs, which can also be classified into two types: a direct (DRBFN) and an indirect (IRBFN) RBFN procedure. In the present procedures, the width of the RBFs is the only adjustable parameter according to a(i) = betad(i), where d(i) is the distance from the ith centre to the nearest centre. The IRBFN method is more accurate than the DRBFN one and experience so far shows that beta can be chosen in the range 7 < or = beta 10 for the former. Different combinations of RBF centres and collocation points (uniformly and randomly distributed) are tested on both regularly and irregularly shaped domains. The results for a 1D Poisson's equation show that the DRBFN and the IRBFN procedures achieve a norm of error of at least O(1.0 x 10(-4)) and O(1.0 x 10(-8)), respectively, with a centre density of 50. Similarly, the results for a 2D Poisson's equation show that the DRBFN and the IRBFN procedures achieve a norm of error of at least O(1.0 x 10(-3)) and O(1.0 x10(-6)) respectively, with a centre density of 12 X 12.


Assuntos
Modelos Biológicos , Redes Neurais de Computação , Distribuição de Poisson
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