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1.
Int J Tuberc Lung Dis ; 27(11): 858-863, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37880894

RESUMO

BACKGROUND: Respiratory diseases of infectious, allergic, neoplastic or degenerative origin are due to the interaction of environmental and occupational risk factors, individual susceptibility and other co-factors and comorbidities. Asthma and other respiratory pathologies can be worsened by climate change and exposure to other agents in occupational environments.METHODS: PubMed and Scopus, and several websites on public and occupational health were queried to find publications and documents on work-related respiratory diseases, asthma, rhinitis, chronic obstructive pulmonary disease (COPD), pneumoconiosis and allergic alveolitis in association with climate change.RESULTS: Most of the retrieved articles concerned asthma (75 in Scopus), while the other topics were less frequently covered in the scientific literature, with a maximum of 29 papers for rhinitis and 23 for COPD. The most important terms highlighted by the word clouds were 'health', 'air', 'pollution', and, only for asthma and rhinitis, 'pollen' and 'allergic/allergy'. Website data on public and occupational health, and climate change were reported.CONCLUSIONS: Assessment and management of respiratory diseases that recognise occupational exposures should be improved, and more research into integrated approaches should be favoured. Health surveillance practices for workers exposed to agents that cause respiratory diseases should be implemented. The development of biomarkers of exposure, effect and susceptibility needs further study.


Assuntos
Asma , Hipersensibilidade , Doenças Profissionais , Exposição Ocupacional , Doença Pulmonar Obstrutiva Crônica , Transtornos Respiratórios , Doenças Respiratórias , Rinite , Humanos , Mudança Climática , Asma/etiologia , Asma/complicações , Hipersensibilidade/epidemiologia , Doenças Profissionais/epidemiologia , Doenças Profissionais/etiologia , Exposição Ocupacional/efeitos adversos , Doença Pulmonar Obstrutiva Crônica/complicações , Doenças Respiratórias/complicações
2.
BJOG ; 2023 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-37156239

RESUMO

OBJECTIVE: To examine prevalence of novel newborn types among 541 285 live births in 23 countries from 2000 to 2021. DESIGN: Descriptive multi-country secondary data analysis. SETTING: Subnational, population-based birth cohort studies (n = 45) in 23 low- and middle-income countries (LMICs) spanning 2000-2021. POPULATION: Liveborn infants. METHODS: Subnational, population-based studies with high-quality birth outcome data from LMICs were invited to join the Vulnerable Newborn Measurement Collaboration. We defined distinct newborn types using gestational age (preterm [PT], term [T]), birthweight for gestational age using INTERGROWTH-21st standards (small for gestational age [SGA], appropriate for gestational age [AGA] or large for gestational age [LGA]), and birthweight (low birthweight, LBW [<2500 g], nonLBW) as ten types (using all three outcomes), six types (by excluding the birthweight categorisation), and four types (by collapsing the AGA and LGA categories). We defined small types as those with at least one classification of LBW, PT or SGA. We presented study characteristics, participant characteristics, data missingness, and prevalence of newborn types by region and study. RESULTS: Among 541 285 live births, 476 939 (88.1%) had non-missing and plausible values for gestational age, birthweight and sex required to construct the newborn types. The median prevalences of ten types across studies were T+AGA+nonLBW (58.0%), T+LGA+nonLBW (3.3%), T+AGA+LBW (0.5%), T+SGA+nonLBW (14.2%), T+SGA+LBW (7.1%), PT+LGA+nonLBW (1.6%), PT+LGA+LBW (0.2%), PT+AGA+nonLBW (3.7%), PT+AGA+LBW (3.6%) and PT+SGA+LBW (1.0%). The median prevalence of small types (six types, 37.6%) varied across studies and within regions and was higher in Southern Asia (52.4%) than in Sub-Saharan Africa (34.9%). CONCLUSIONS: Further investigation is needed to describe the mortality risks associated with newborn types and understand the implications of this framework for local targeting of interventions to prevent adverse pregnancy outcomes in LMICs.

3.
Braz. j. med. biol. res ; 54(1): e10037, 2021. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1142569

RESUMO

Given the increase of women with excess weight or obesity and its possible effects on birth weight, the present study aimed to investigate the association between pregestational maternal body mass index (BMI) and birth weight in a birth cohort from Ribeirão Preto, SP, Brazil. This was a prospective study conducted on 1362 mother-child pairs involving singleton births. The women were evaluated using standardized questionnaires during the second trimester of pregnancy and at the time of childbirth. Information about the newborns was obtained from their medical records. The dependent variable was birth weight, categorized as low, adequate, or high. The independent variable was pregestational maternal BMI, categorized as malnutrition, adequate weight, overweight, and obesity. A multinomial regression model was used to estimate the crude and adjusted relative risk (RR) of low and high birth weight. A high frequency of pregestational excess weight (39.6%) was detected and found to be independently associated with high birth weight (RR=2.13, 95%CI: 1.19-3.80 for overweight and RR=3.34, 95%CI: 1.80-6.19 for obese pregnant women). There was no association between pregestational malnutrition and low birth weight (RR=1.70; 95%CI: 0.81-3.55). The present data showed a high rate of women with excess pregestational weight, supporting the hypothesis that pregestational BMI may contribute to high birth weight babies and indicating the need for actions aiming to prevent excessive weight in women at reproductive age.


Assuntos
Humanos , Masculino , Feminino , Gravidez , Recém-Nascido , Adulto , Adulto Jovem , Peso ao Nascer , Índice de Massa Corporal , Segundo Trimestre da Gravidez , Brasil/epidemiologia , Estudos Prospectivos , Sobrepeso/epidemiologia , Obesidade/epidemiologia
4.
Braz. j. med. biol. res ; 54(1): e10253, 2021. tab, graf
Artigo em Inglês | LILACS, Coleciona SUS | ID: biblio-1142570

RESUMO

During pregnancy, metabolic changes that develop in women may increase the risk of diseases and conditions that may also harm the life of the growing fetus. The aim of the present study was to identify and compare the metabolic profile (MP) during pregnancy in two birth cohorts in 2010 in the cities of Ribeirão Preto (RP) and São Luís (SL), Brazil. Pregnant women (1393 in RP and 1413 in SL) were studied; information was obtained through questionnaires in addition to anthropometric, biochemical, and blood pressure measurements. Data are presented as means and proportions. To compare the characteristics of pregnant women in both cities, chi-squared and Student's t-tests were applied, with 5% significance level. Ribeirão Preto presented higher mean values than SL for pre-gestational body mass index (24.5 vs 23 kg/m2, P<0.001), systolic (108.4 vs 102.8 mmHg, P<0.001) and diastolic (65.9 vs 61.8 mmHg, P<0.001) blood pressure, total cholesterol (226.3 vs 213.7 mg/dL, P<0.001) and fractions, and glycemia (84.5 vs 80.2 mg/dL, P<0.001), except for triglycerides (P=0.135). Women from RP also showed higher rates of pre-gestational overweight and obesity compared with SL (40.1 vs 25.8%). In the present study, pregnant women in RP had a worse gestational metabolic profile than those in SL, with higher pre-gestational excess weight, indicating that nutritional transition was more advanced in the more developed city.


Assuntos
Humanos , Feminino , Adulto , Adulto Jovem , Gravidez/metabolismo , Metaboloma , Fatores Socioeconômicos , Brasil/epidemiologia , Índice de Massa Corporal , Estudos de Coortes , Cidades
5.
Braz J Med Biol Res ; 54(1): e10037, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33295534

RESUMO

Given the increase of women with excess weight or obesity and its possible effects on birth weight, the present study aimed to investigate the association between pregestational maternal body mass index (BMI) and birth weight in a birth cohort from Ribeirão Preto, SP, Brazil. This was a prospective study conducted on 1362 mother-child pairs involving singleton births. The women were evaluated using standardized questionnaires during the second trimester of pregnancy and at the time of childbirth. Information about the newborns was obtained from their medical records. The dependent variable was birth weight, categorized as low, adequate, or high. The independent variable was pregestational maternal BMI, categorized as malnutrition, adequate weight, overweight, and obesity. A multinomial regression model was used to estimate the crude and adjusted relative risk (RR) of low and high birth weight. A high frequency of pregestational excess weight (39.6%) was detected and found to be independently associated with high birth weight (RR=2.13, 95%CI: 1.19-3.80 for overweight and RR=3.34, 95%CI: 1.80-6.19 for obese pregnant women). There was no association between pregestational malnutrition and low birth weight (RR=1.70; 95%CI: 0.81-3.55). The present data showed a high rate of women with excess pregestational weight, supporting the hypothesis that pregestational BMI may contribute to high birth weight babies and indicating the need for actions aiming to prevent excessive weight in women at reproductive age.


Assuntos
Peso ao Nascer , Índice de Massa Corporal , Adulto , Brasil/epidemiologia , Feminino , Humanos , Recém-Nascido , Masculino , Obesidade/epidemiologia , Sobrepeso/epidemiologia , Gravidez , Segundo Trimestre da Gravidez , Estudos Prospectivos , Adulto Jovem
6.
Braz J Med Biol Res ; 54(1): e10253, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33295536

RESUMO

During pregnancy, metabolic changes that develop in women may increase the risk of diseases and conditions that may also harm the life of the growing fetus. The aim of the present study was to identify and compare the metabolic profile (MP) during pregnancy in two birth cohorts in 2010 in the cities of Ribeirão Preto (RP) and São Luís (SL), Brazil. Pregnant women (1393 in RP and 1413 in SL) were studied; information was obtained through questionnaires in addition to anthropometric, biochemical, and blood pressure measurements. Data are presented as means and proportions. To compare the characteristics of pregnant women in both cities, chi-squared and Student's t-tests were applied, with 5% significance level. Ribeirão Preto presented higher mean values than SL for pre-gestational body mass index (24.5 vs 23 kg/m2, P<0.001), systolic (108.4 vs 102.8 mmHg, P<0.001) and diastolic (65.9 vs 61.8 mmHg, P<0.001) blood pressure, total cholesterol (226.3 vs 213.7 mg/dL, P<0.001) and fractions, and glycemia (84.5 vs 80.2 mg/dL, P<0.001), except for triglycerides (P=0.135). Women from RP also showed higher rates of pre-gestational overweight and obesity compared with SL (40.1 vs 25.8%). In the present study, pregnant women in RP had a worse gestational metabolic profile than those in SL, with higher pre-gestational excess weight, indicating that nutritional transition was more advanced in the more developed city.


Assuntos
Metaboloma , Gravidez/metabolismo , Adulto , Índice de Massa Corporal , Brasil/epidemiologia , Cidades , Estudos de Coortes , Feminino , Humanos , Fatores Socioeconômicos , Adulto Jovem
7.
Phys Rev Lett ; 115(24): 240501, 2015 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-26705615

RESUMO

We engineer a quantum bath that enables entropy and energy exchange with a one-dimensional Bose-Hubbard lattice with attractive on-site interactions. We implement this in an array of three superconducting transmon qubits coupled to a single cavity mode; the transmons represent lattice sites and their excitation quanta embody bosonic particles. Our cooling protocol preserves the particle number-realizing a canonical ensemble-and also affords the efficient preparation of dark states which, due to symmetry, cannot be prepared via coherent drives on the cavity. Furthermore, by applying continuous microwave radiation, we also realize autonomous feedback to indefinitely stabilize particular eigenstates of the array.

8.
Int J Mol Med ; 34(6): 1537-46, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25319350

RESUMO

Synthetic biomaterials combined with cells and osteogenic factors represent a promising approach for the treatment of a number of orthopedic diseases, such as bone trauma and congenital malformations. To guarantee optimal biological properties, bone substitutes are prepared with a 3D structure and porosity grade functional to drive cell migration and proliferation, diffusion of factors, vascularization and cell waste expulsion. In this study, synthetic hydroxyapatite (HA) or rat bone extracellular matrix (BP) were examined in an effort to optimize the mechanical properties and osteogenic activity of poly-ε-caprolactone scaffolds prepared with alginate threads (PCL-AT). Using rabbit bone marrow-derived mesenchymal stem cells (rMSCs), the effects of PCL composite substrates on cell adhesion, growth and osteogenic differentiation were evaluated. Micro-CT analysis and scanning electron microscopy evidenced that porous PCL scaffolds containing HA or BP acquire a trabecular bone-like structure with interconnected pores homogenously distributed and are characterized by a pore diameter of approximately 10 µm (PCL-AT-BP) or ranging from 10 to 100 µm. Although the porosity grade of both PCL-AT-HA and PCL-AT-BP promoted optimal conditions for the cell growth of rMSCs at the early phase, the presence of BP was crucial to prolong the cell viability at the late phase. Moreover, a precocious expression of Runx2 (at 7 days) was observed in PCL-AT-BP in combination with osteogenic soluble factors suggesting that BP controls better than HA the osteogenic maturation process in bone substitutes.


Assuntos
Osso e Ossos/efeitos dos fármacos , Células-Tronco Mesenquimais/efeitos dos fármacos , Osteogênese/efeitos dos fármacos , Poliésteres/farmacologia , Alicerces Teciduais/química , Alginatos/química , Animais , Células da Medula Óssea/efeitos dos fármacos , Células da Medula Óssea/metabolismo , Substitutos Ósseos/química , Substitutos Ósseos/farmacologia , Osso e Ossos/citologia , Osso e Ossos/metabolismo , Adesão Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Durapatita/química , Durapatita/farmacologia , Matriz Extracelular/química , Expressão Gênica/efeitos dos fármacos , Ácido Glucurônico/química , Ácidos Hexurônicos/química , Células-Tronco Mesenquimais/metabolismo , Células-Tronco Mesenquimais/ultraestrutura , Microscopia Eletrônica de Varredura , Osteocalcina/genética , Osteogênese/genética , Osteopontina/genética , Poliésteres/química , Coelhos , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Tempo , Microtomografia por Raio-X
9.
J Tissue Eng Regen Med ; 8(9): 694-705, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22972614

RESUMO

So far, osteogenic protein 1 (OP1) is biotechnologically produced and approved for the treatment of human lumbar spine fusion and long bone non-union fractures. When combined with the TAT sequence, it has been demonstrated in vitro to be easily taken up by PC12 neuronal cells and to acquire its biological activity after intracellular refolding. In this study, TAT-OP1 was shown to be a useful strategy to efficiently drive denatured OP1 into mouse MC3T3E1 pre-osteoblasts. The correct in vitro protein refolding was verified by the activation of the BMP cascade, while the osteogenic potential of OP1 was demonstrated by increased expression of alkaline phosphatase, osteonectin and osteocalcin.


Assuntos
Proteína Morfogenética Óssea 7/farmacologia , Osteogênese/efeitos dos fármacos , Produtos do Gene tat do Vírus da Imunodeficiência Humana/farmacologia , Ativinas/metabolismo , Animais , Receptores de Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular/efeitos dos fármacos , Rastreamento de Células , Humanos , Camundongos , Osteocalcina/metabolismo , Osteopontina/metabolismo , Células PC12 , Fosforilação/efeitos dos fármacos , Ratos , Proteínas Recombinantes de Fusão/farmacologia , Proteínas Smad/metabolismo , Soluções , Espectrometria de Massas por Ionização por Electrospray
10.
J Phys Condens Matter ; 25(40): 404216, 2013 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-24025690

RESUMO

We present a general approach to describe slowly driven quantum systems both in real and imaginary time. We highlight many similarities, qualitative and quantitative, between real and imaginary time evolution. We discuss how the metric tensor and the Berry curvature can be extracted from both real and imaginary time simulations as a response of physical observables. For quenches ending at or near the quantum critical point, we show the utility of the scaling theory for detecting the location of the quantum critical point by comparing sweeps at different velocities. We briefly discuss the universal relaxation to equilibrium of systems after a quench. We finally review recent developments of quantum Monte Carlo methods for studying imaginary time evolution. We illustrate our findings with explicit calculations using the transverse-field Ising model in one dimension.


Assuntos
Modelos Químicos , Modelos Moleculares , Modelos Estatísticos , Teoria Quântica , Termodinâmica , Simulação por Computador
11.
Ciudad Autónoma de Buenos Aires; Ministerio de Salud de la Nación. Dirección de Investigación en Salud; 2013. 1 p.
Não convencional em Espanhol | ARGMSAL, BINACIS | ID: biblio-1526945

RESUMO

INTRODUCCIÓN La prematuridad constituye uno de los mayores determinantes actuales de morbimortalidad en la infancia, en particular en los recién nacidos (RN) de menos de 1 500 gramos, es decir, recién nacidos de muy bajo peso (RNMBP). La Red Neonatal Sudamericana (NEOCOSUR) incluye a siete países: Argentina, Bolivia, Brasil, Chile, Paraguay, Perú y Uruguay. OBJETIVOS Estudiar los factores de riesgo asociados a la mortalidad neonatal en RNMBP. MÉTODOS Se utilizó un diseño observacional, descriptivo y analítico, retrospectivo de una cohorte histórica. Se trabajó con la base de datos NEOCOSUR 2000-2011, con 11 455 registros de RNMBP. Se calculó el estadístico OR (IC 95%) por regresión logística para explorar el efecto independiente de diversas condiciones (factores de riesgo) sobre la mortalidad y morbilidad, ajustado para potenciales confusores. Se estimó el efecto del corticoide prenatal sobre la mortalidad neonatal utilizando el método de pareamiento. RESULTADOS La tasa de mortalidad neonatal (TMN) fue de 22,3%, con una tendencia creciente (p=0,002). La TMN estandarizada fue de 101,6 (Argentina 84,7). Se observó una elevada variabilidad en la mortalidad ajustada por riesgo en los diferentes centros, aunque descendió en el 60% de los casos. No se registraron diferencias significativas en las TMN específicas según peso al nacer (PN) o edad gestacional (EG) entre NEOCOSUR y Argentina. No se observaron diferencias en la TMN según el volumen de RN internados. Los factores independientemente asociados a menor mortalidad de los RNMBP fueron la administración de corticoides prenatal, puntaje z del PN, hipertensión y cesárea. La TMN del sector público ascendió al 23,2%, y la del sector privado fue del 19,8% (OR 1,22; IC 95%: 1,10- 1,36, p<0,001). La administración prenatal de corticoides redujo en un 40% la probabilidad de mortalidad neonatal. La mediana de la estadía fue de 61 días. DISCUSIÓN Se identificaron diversas condiciones perinatales asociadas a la mortalidad neonatal en RNMBP, y se demostró el impacto de la administración de corticoides prenatales.


Assuntos
Recém-Nascido Prematuro , Mortalidade Infantil , Fatores de Risco , Estudo Multicêntrico
12.
G Ital Med Lav Ergon ; 33(2): 134-48, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-21796921

RESUMO

Chapter IV and V of Title VIII of D.Lgs 81/2008, implementing the Directives 2004/40/EC respectively (protection of workers exposed to electromagnetic fields) and 2006/25/EC (protection of workers exposed to artificial optical radiation), make frequent reference to the workers as "at particular risk" namely those workers who, by their biological or pathological characteristics, lifestyles, multiple exposure to other risk factors, may be more susceptible to the effects of electromagnetic fields or optical radiation. The identification of workers with particular sensitivity is essential for health surveillance, in particular regarding the determination of fitness. The operational guidance on Title VIII of D.Lgs 81/2008 drafted by the Italian Technical Coordination for Safety in the workplace of Regions and Autonomous Provinces (Document No. 1-2009), in collaboration with ISPESL and ISS, includes a preliminary identification of the categories of workers considered most susceptible to the risk from exposure to electromagnetic fields and optical radiation. On the basis of this information the authors identified more focused and structured classes of workers to be considered as "particularly sensitive to risk", it is not only related to a specific wavelength, but based on a comprehensive risk assessment in individual exposure situation, with regard to the exposure levels, any multiple exposures, the possibility of adequate personal protection.


Assuntos
Campos Eletromagnéticos/efeitos adversos , Exposição Ocupacional/efeitos adversos , Exposição Ocupacional/legislação & jurisprudência , Aptidão Física , Radiação não Ionizante/efeitos adversos , Humanos , Itália , Vigilância da População , Medição de Risco , Fatores de Risco
13.
G Ital Med Lav Ergon ; 33(3 Suppl): 376-9, 2011.
Artigo em Italiano | MEDLINE | ID: mdl-23393880

RESUMO

Critical features in applying the EU directive 2004/40/CE on the minimum health and safety requirements regarding the exposure of workers to risks arising from electromagnetic fields, jointly with the need to update the scientific rationale on the basis of the new international recommendations (ICNIRP), lead the EU Commission to stop the implementation of the directive by the member states and to start a pathway of consultation and study involving experts and representatives of Institutions and social partners. The process is ongoing, but the analysis of critical features of the EU directive 2004/40/CE allowed to identify the reference points in order to arrange a new directive.


Assuntos
Campos Eletromagnéticos , Saúde Ocupacional/legislação & jurisprudência , União Europeia , Humanos
14.
Protein Eng Des Sel ; 23(11): 889-97, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20889531

RESUMO

Osteogenic protein 1 (OP1), also known as bone morphogenic protein-7 (BMP7), is a multifunctional cytokine with demonstrated neurogenic potential. As the recombinant OP1 (rhOP1) was shown to provide axonal guidance cues and to prevent the reduction of dendritic growth in the injury-induced cortical cultures, it was suggested that an in vivo efficient rhOP1 delivery could enhance neurite growth and functional reconnectivity in the damaged brain. In the present work, we engineered a chimeric molecule in which rhBMP7 was fused to a protein transduction domain derived from HIV-1 TAT protein to deliver the denatured recombinant BMP7 into cells and obtain its chaperone-mediated folding, circumventing the expensive and not much efficient in vitro refolding procedures. When tested on rat PC12 cells, a widely used in vitro neurogenic differentiation model, the resulting fusion protein (rhTAT-OP1) demonstrated to enter fastly into the cells, lose HIV-TAT sequence and interact with membrane receptors activating BMP pathway by SMAD 1/5/8 phosphorylation. In comparison with nerve growth factor (NGF) and BMP7, it proved itself effective to induce the formation of more organized H and M neurofilaments. Moreover, if used in combination with NGF, it stimulated a significant (P < 0.05) and more precocious dendritic outgrowth with respect to NGF alone. These results indicate that rhTAT-OP1 fused with TAT transduction domain shows neurogenic activity and may be a promising enhancer factor in NGF-based therapies.


Assuntos
Proteína Morfogenética Óssea 7/genética , Proteína Morfogenética Óssea 7/metabolismo , Fator de Crescimento Neural/metabolismo , Neurogênese , Produtos do Gene tat do Vírus da Imunodeficiência Humana/genética , Produtos do Gene tat do Vírus da Imunodeficiência Humana/metabolismo , Sequência de Aminoácidos , Animais , Proteína Morfogenética Óssea 7/isolamento & purificação , Proliferação de Células , Dendritos/metabolismo , Expressão Gênica , HIV/genética , HIV/metabolismo , Humanos , Dados de Sequência Molecular , Células PC12 , Estrutura Terciária de Proteína , Ratos , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Produtos do Gene tat do Vírus da Imunodeficiência Humana/isolamento & purificação
15.
Curr Alzheimer Res ; 7(7): 591-601, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20704555

RESUMO

Although Alzheimer's disease (AD) is considered a neurodengenerative disorders, in the last few years a large amount of evidence has suggested that it is also a vascular pathology characterized by increased capillary density and expression of angiogenic factors. In AD the endothelium degenerates, promoting local neuroinflammation and activation of brain endothelium, perivascular microglia, pericytes, astrocytes. Excess tumor necrosis factor (TNF) in the cerebrospinal fluid (CSF), at a concentration of 25 times higher than in the control group, has been demonstrated in AD. Recent studies provide evidence that treatment with TNF-α antagonists may result in a rapid cognitive improvement in AD patients. In the present work we investigated the role of astrocytes in AD angiogenesis and neuroinflammation by means of conditioned media of untreated and Aß-treated rat hippocampal astrocytes (RHAs) on rat microvascular endothelial cells (RCECs). The results demonstrated that RHA media increase RCEC proliferation and capillary-like structure formation. Moreover RHAs secrete IL-1ß and, only after the Aß1-42 treatment, TNF-α promotes RCEC release of IL-1ß, IL-6 and TNF-α. The removal of IL-1ß, TNF-α and/or VEGF, a strong angiogenic inducer highly over-expressed in AD brains, by means of specific antibody-coated beads in RHA media affects RCEC release of IL-1ß, IL-6 and TNF-α. We hypothesised that astrocytes contribute to AD angiogenesis and neuroinflammation by the direct release of pro-inflammatory cytokines. The effect of an anti-inflammatory agent, such as etanercept, decreased RCEC in vitro cytokine release. This could be compared to the effect found in our experiments with antibody anti TNF-α-coated beads.


Assuntos
Peptídeos beta-Amiloides/fisiologia , Astrócitos/metabolismo , Astrócitos/patologia , Hipocampo/metabolismo , Hipocampo/patologia , Neovascularização Patológica/metabolismo , Neovascularização Patológica/patologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Doença de Alzheimer/fisiopatologia , Animais , Animais Recém-Nascidos , Células Cultivadas , Hipocampo/fisiopatologia , Inflamação/metabolismo , Inflamação/patologia , Inflamação/fisiopatologia , Neovascularização Patológica/fisiopatologia , Ratos , Ratos Sprague-Dawley
16.
Int J Mol Med ; 25(2): 195-202, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20043127

RESUMO

Increasing pancreatic islet survival and function is a starting point for obtaining a valuable bioartificial pancreas for the treatment of type 1 diabetes. In this context, decellularized matrices, obtained after the removal of tissue cellular part, are known to support in vitro adhesion, growth, and function of several cell types. We demonstrate that a homologous acellular pancreatic matrix is a suitable scaffold for rat islet cultures maintaining their long-term viability and function. Islets adhered to the pancreatic matrix showed a constant glucose-induced insulin release during long-term in vitro incubation, while islets cultured without a matrix or on the liver matrix showed a progressive reduction. In order to obtain implantable devices, acellular matrix/islet cultures were entrapped into poly(vinyl alcohol) (PVA)/ poly(ethylene glycol) (PEG) tubes obtained by the freezing/thawing procedure. Under this condition, an in vitro constant insulin release was detected. The devices were then implanted into diabetic rats where reduced insulin requirement was noted suggesting insulin secretory activity of islets contained in the device. Indeed, immunofluorescence confirmed the presence of insulin- and glucagon-producing cells into the explanted devices. These data show that PVA/PEG semi-permeable membrane can obtain devices that restore, at least in part, insulin secretion.


Assuntos
Matriz Extracelular/metabolismo , Ilhotas Pancreáticas/citologia , Engenharia Tecidual/métodos , Alicerces Teciduais , Análise de Variância , Animais , Reatores Biológicos , Diabetes Mellitus Experimental/tratamento farmacológico , Imunofluorescência , Glucose/administração & dosagem , Glucose/metabolismo , Insulina/metabolismo , Insulina/farmacologia , Ilhotas Pancreáticas/metabolismo , Masculino , Microscopia Eletrônica de Varredura , Polietilenoglicóis , Álcool de Polivinil , Ratos , Ratos Wistar , Engenharia Tecidual/instrumentação
17.
Mol Med Rep ; 3(1): 127-32, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21472211

RESUMO

Several members of the ribonuclease superfamily possess a variety of interesting biological properties, including ribonucleolytic, angiogenic, antiproliferative, cytotoxic, embryotoxic, aspermatogenic and antitumoral activity. In this study, we report the purification from bovine milk of a protein with structural and enzymatic properties very similar to those of ribonuclease-4 (RNase-4), which is normally present in the liver and lungs, and examined its functional properties, biological activity and cytotoxic effects. RNase-4, at physiological concentrations, had a positive effect on the vitality and proliferation of human umbilical vein endothelial cells. Moreover, it induced an increase in cellular migration and the formation of in vitro capillary-like structures. We also evaluated the effect of RNase-4 in vitro on human breast, colorectal and cervical carcinoma cell lines. The protein was revealed to have a cytotoxic effect similar to that of RNase-A. We suggest that the positive effects of RNase-4 on normal cells were due to its particularly close interaction with RNase inhibitor, while good conformational stability and resistance to proteolytic degradation potentially favour ribonuclease cytotoxicity.

18.
Int J Mol Med ; 24(6): 837-45, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19885627

RESUMO

Cord blood (CB) is a source of hematopoietic stem cells (HSCs) and is an alternative to bone marrow for allogenic transplantation in patients with hematological disorders. The improvement of HSC in vitro expansion is one of the main challenges in cell therapy. Stromal components and soluble factors, such as cytokines, can be useful to induce in vitro cell expansion. Hence, we investigated whether feeder-layers from new stromal cell lines and different exogenous cytokine cocktails induce HSC expansion in middle-term cultures. CB HSC middle-term expansion was carried out in co-cultures on different feeder-layers exposed to three different cytokine cocktails. CB HSC expansion was also carried out in stroma-free cultures in the presence of different cytokine cocktails. Clonogenic tests were performed, and cell growth levels were evaluated. Moreover, the presence of VCAM-1 mRNA was assessed, and the mesenchymal cell-like phenotype expression was detected. All feeder-layers were able to induce a significant clonogenic growth with respect to the control culture, and all of the cytokine cocktails induced a significant increase in CB cell expansion indexes, even though no potential variation dependent on their composition was noted. The modulative effects of the different cocktails, exerted on each cell line used, was dependent on their composition. Finally, all cell lines were positive for CD73, CD117 and CD309, similar to mesenchymal stem cells present in adult bone marrow and in other human tissues, and negative for the hematopoietic markers. These data indicate that our cell lines have, not only a stromal cell-like phenotype, but also a mesenchymal cell-like phenotype, and they have the potential to support in vitro expansion of CB HSCs. Moreover, exogenous cytokines can be used in synergism with feeder-layers to improve the expansion levels of CB HSCs in preparation for their clinical use in allogenic transplantation.


Assuntos
Técnicas de Cultura de Células/métodos , Citocinas/farmacologia , Sangue Fetal/citologia , Células-Tronco Hematopoéticas/citologia , Células Estromais/citologia , Animais , Linhagem Celular , Proliferação de Células/efeitos dos fármacos , Meios de Cultura , Sangue Fetal/efeitos dos fármacos , Sangue Fetal/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Células-Tronco Hematopoéticas/metabolismo , Humanos , Imuno-Histoquímica , Leucócitos Mononucleares/metabolismo , Camundongos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Células Estromais/efeitos dos fármacos , Células Estromais/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo
19.
Oral Implantol (Rome) ; 2(1): 37-52, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23285356

RESUMO

In Surgical Endodontics we face complex situations that require the knowlflap and application of both principles of endodontics (cleansing shaping and filling) in the root management, and the principles of surgery (asepsis, non harmfulness and hemostasis) in the phase of access to the root. Among the factors of surgical relevance that for which have been proposed with the largest number of alternatives is the design of access flap. That clearly indicates that not only one flap design can be ideal in all clinical situations. In this article all proposed access flap designs are evaluated in the light of their degree of compliance with ideal requirements in different circumstances. A clear pattern in the decision-making criteria for the selection of access flaps is proposed.

20.
Oral Implantol (Rome) ; 2(4): 2-10, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23285369

RESUMO

AIMS.: In Misch Class IV dental implants are not normally placed at the same time as the sinus lift procedure. For this type of situation the use of several devices to immediately stabilise implants lacking in primary stability is proposed. Among these, the titanium S.I.S. plate results as being the most straightforward. This study proposes the evaluation of the effectiveness and stability of the results of this method in the short term on a greater number of patients, monitoring bones levels and implant stability. METHOD.: 14 patients were selected, 9 males and 5 females, aged between 43 and 75 years of age. Overall, 42 implants were placed in the upper posterior edentulous zones with Misch Class IV atrophy including first and second premolars and first molars, opposite fixed teeth, and were stabilised using the S.I.S. plate. RESULTS.: Radiographic controls and ISQ measurements with AFR at 1, 6 and 12 months after loading testify to the stability of the bone levels which concur with success criteria found in literature. The technique described seems to be able to ensure success in cases of Misch Class IV with contemporaneous placement of the osseo-integrated implants. CONCLUSION.: This clinical study, even if carried out on a small number of patients (14) and implants (42) represents the largest case history published. The technique described seems to ensure the success of cases of Misch Class IV with contemporaneous placement of osseo-integrated implants. The technique is straightforward and reproducible and does not cause further trauma. The S.I.S. allows for the stabilisation of the dental implants and the residual crest when there is a lack of primary stability. In Misch Class IV this means a considerable reduction in treatment times.

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