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1.
Reumatismo ; 72(4): 189-196, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33677945

RESUMO

The role of 25-OH-vitamin D in the assessment of coronavirus disease 19 (COVID-19) has not been investigated. We sought to investigate the prevalence of 25-OH-vitamin D deficiency among COVID-19 patients, and to determine the associations between 25-OH-vitamin D status and the severity of the disease. We have conducted a retrospective observational study of COVID-19 patients admitted to the University of Verona Hospital Trust. Demographic, clinical and biochemical parameters were collected at hospital admission, and serum 25-OH-vitamin D levels were measured. The following outcomes were assessed: arterial partial oxygen pressure (PaO2); C-reactive protein (CRP); length of hospitalization; requirement of oxygen therapy; non-invasive ventilation (NIV); mechanical ventilation; and death. Among 61 patients enrolled, 72.1% was 25-OH-vitamin D deficient (<20 ng/mL) and 57.4% had 25-OHvitamin D <15 ng/mL. Patients with arterial PaO2 <60 mmHg had significantly lower mean 25-OH-vitamin D levels compared to patients with PaO2 ≥60 mmHg (13.3 ng/mL vs 20.4 ng/mL respectively, p=0.03). Vitamin D deficiency was associated with 3-fold higher risk of having arterial pO2 <60 mmHg. 25-OH-vitamin D deficiency was associated with increased CRP and dyspnea. 25-OH-vitamin D deficiency was associated with more severe systemic inflammatory response and respiratory failure in COVID-19 patients.


Assuntos
COVID-19/sangue , Vitamina D/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Proteína C-Reativa/análise , COVID-19/epidemiologia , Comorbidade , Suscetibilidade a Doenças , Dispneia/etiologia , Feminino , Fibrinogênio/análise , Humanos , Itália/epidemiologia , Tempo de Internação/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Oxigênio/sangue , Pressão Parcial , Prevalência , Respiração Artificial/estatística & dados numéricos , Estudos Retrospectivos , Índice de Gravidade de Doença , Deficiência de Vitamina D/sangue , Deficiência de Vitamina D/epidemiologia
2.
Arch Ital Biol ; 156(1-2): 64-86, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-30039837

RESUMO

Some food/food components have been the object of request of authorization to the use of health claims related to cognitive function in adults and compliant with the Regulation (EC) 1924/2006. Most of the requests have received a negative opinion by the European Food Safety Authority (EFSA) also because of the choice of not appropriate outcome variables (OVs) and methods of measurement (MMs) selected in the trials used to substantiate the claim. This manuscript referes to the collection, collation and critical analysis of OVs and MMs related to cognitive function in adults. OVs and MMs were collected from the EFSA Guidance document and the applications for authorization of health claims pursuant to the Articles 13(5). The critical analysis of OVs and MMs, performed by a literature review, was aimed at defining their appropriateness in the context of a specific claimed effect. The results highlight the importance of an adequate choice of OVs and MMs for an effective substantiation of the claims related to cognitive functioning. The information provided in this document may serve to EFSA for updating the guidance on the scientific requirements for health claims related to cognitive functions, but also for a better design of randomized controlled trials aimed at substantiating such health claims.


Assuntos
Cognição , Dieta , Alimentos , Inocuidade dos Alimentos , Humanos , Legislação de Medicamentos , Testes Neuropsicológicos
3.
Nutr Metab Cardiovasc Dis ; 27(6): 473-503, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28434807

RESUMO

BACKGROUND AND AIMS: The high number of negative opinions from the European Food Safety Authority (EFSA) to the requests for authorization of health claims is largely due to the design of human intervention studies, including the inappropriate choice of outcome variables (OVs) and of their methods of measurement (MMs). The present manuscript reports the results of an investigation aimed to collect, collate and critically analyse the information in relation to claimed effects, OVs and MMs, in the context of protection against oxidative damage and cardiovascular health compliant with Regulation 1924/2006. METHODS AND RESULTS: Claimed effects, OVs and the related MMs were collected from EFSA Guidance documents and applications for authorization of health claims under Articles 13.5 and 14. The OVs and their MMs were evaluated only if the claimed effect was sufficiently defined and was considered beneficial by EFSA. The collection, collation and critical analysis of the relevant scientific literature consisted in the definition of the keywords, the PubMed search strategies and the creation of databases of references. The critical analysis of the OVs and their MMs was performed on the basis of the literature review and was aimed at defining the appropriateness of OVs and MMs in the context of the specific claimed effects. CONCLUSIONS: The information provided in this document could serve to EFSA for the development of further guidance on the scientific requirements for health claims, as well as to the stakeholders for the proper design of human intervention studies aimed to substantiate such health claims.


Assuntos
Antioxidantes/administração & dosagem , Doenças Cardiovasculares/prevenção & controle , Inocuidade dos Alimentos , Alimento Funcional , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/efeitos adversos , Biomarcadores/sangue , Doenças Cardiovasculares/sangue , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/epidemiologia , Dano ao DNA/efeitos dos fármacos , Europa (Continente)/epidemiologia , Alimento Funcional/efeitos adversos , Regulamentação Governamental , Análise de Perigos e Pontos Críticos de Controle , Humanos , Legislação sobre Alimentos , Peroxidação de Lipídeos/efeitos dos fármacos , Fatores de Proteção , Carbonilação Proteica/efeitos dos fármacos , Medição de Risco , Fatores de Risco
4.
Acta Biomater ; 42: 147-156, 2016 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-27449338

RESUMO

UNLABELLED: Protein adsorption is the first and decisive step to define cell-biomaterial interaction. Guiding the adsorption of desired protein species may represent a viable approach to promote cell activities conducive to tissue regeneration. The aim of the present study was to investigate whether immobilized anti-Fibronectin aptamers could promote the attachment and growth of osteoblastic cells. Polyethyleneglycole diacrylate/thiolated Hyaluronic Acid hydrogels (PEGDA/tHA) were coated with anti-Fibronectin aptamers. Hydrogel loading and Fibronectin bonding were investigated, through spectrophotometry and Bradford assay. Subsequently, human osteoblasts (hOBs) were cultured on hydrogels for 10days in 2D and 3D cultures. Cells were monitored through microscopy and stained for focal adhesions, microfilaments and nuclei using fluorescence microscopy. Samples were also included in paraffin and stained with Hematoxylin-Eosin. Cell number on hydrogels was quantitated over time. Cell migration into the hydrogels was also studied through Calcein AM staining. Aptamers increased the number of adherent hOBs and their cytoplasm appeared more spread and richer in adhesion complexes than on control hydrogels. Viability assays confirmed that significantly more cells were present on hydrogels in the presence of aptamers, already after 48h of culture. When hOBs were encapsulated into hydrogels, cells were more numerous on aptamer-containing PEGDA-tHA. Cells migrated deeper in the gel in the presence of DNA aptamers, appearing on different focus planes. Our data demonstrate that anti-Fibronectin aptamers promote scaffold enrichment for this protein, thus improving cell adhesion and scaffold colonization. STATEMENT OF SIGNIFICANCE: We believe aptamer coating of biomaterials is a useful and viable approach to improve the performance of scaffold materials for both research and possibly clinical purposes, because different medical devices could be envisaged able to capture bioactive mediators from the patients' blood and concentrate them where they are needed, on the biomaterial itself. At the same time, this technology could be used to confer 3D cell culture scaffold with the ability to store proteins, such as Fibronectin, taking it from the medium and capture what is produced by cells. This is an improvement of traditional biomaterials that can be enriched with exogenous molecules but are not able to selectively capture a desired molecule.


Assuntos
Aptâmeros de Peptídeos/farmacologia , Fibronectinas/antagonistas & inibidores , Teste de Materiais/métodos , Alicerces Teciduais/química , Animais , Bovinos , Adesão Celular/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Materiais Revestidos Biocompatíveis/farmacologia , Fibronectinas/metabolismo , Humanos , Hidrogéis/farmacologia , Osteoblastos/citologia , Ligação Proteica/efeitos dos fármacos , Reprodutibilidade dos Testes
5.
J Mater Sci Mater Med ; 27(4): 68, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26886816

RESUMO

The aim of the present work was to investigate the morphology and activity of the murine osteoblastic cell line MC3T3 on control smooth (Machined), commercially available rough (ZT) titanium discs, and on titanium samples obtained by modifying the ZT treatment protocol, and herein labelled as ZTF, ZTM and ZTFM. Cells were evaluated at SEM and immunofluorescence for morphology and cell-to-cell interactions and by MTT assay and real time PCR for cell growth and function. Microscopy showed that ZT modified protocols could differently affect cell shape and distribution. All the tested surfaces showed good biocompatibility by viability assay. However, cells on smoother surfaces appeared to express higher levels of transcript for Collagen 1a1, the main component of extracellular matrix, by real time PCR. Expression of the early differentiation marker Alkaline Phosphatase was higher on ZTF surfaces and ZTM enhanced the expression of later osteoblastic markers Osteoprotegerin and Osteocalcin. Noteworthy, the expression of Connexin 43, a component of cell-to-cell contacts and hemichannels, followed a similar pattern to differentiation marker genes and was higher in cells on ZTM surfaces, consistently with the microscopic observation of cell clusters. Taken together, this data showed that ZTF and ZTM treatment protocols appeared to improve the basal sand-blasting/acid-etching ZT procedure with ZTM surfaces promoting the most mature stage of differentiation.


Assuntos
Materiais Biocompatíveis , Osteoblastos/metabolismo , Titânio/química , Células 3T3 , Animais , Sobrevivência Celular , Regulação da Expressão Gênica/fisiologia , Interações Hidrofóbicas e Hidrofílicas , Camundongos , Microscopia Eletrônica de Varredura , Reação em Cadeia da Polimerase em Tempo Real , Propriedades de Superfície
6.
Rev Med Brux ; 37(4): 205-208, 2016.
Artigo em Francês | MEDLINE | ID: mdl-28981220

RESUMO

The evaluation of the development of young children had to consider the possible detection of neurodevelopmental disorders in particular autism spectrum disorders. When a child of 18 months has a developmental language delay or a defect in social contact, the hypothesis of autism must be considered through a clinical evaluation. We will point out some clinical guidelines and some early signs to detect the trouble and to propose early treatment interventions. This will help to develop specific skills of the child aiming at influencing positively clinical evolution and reducing mental retardation.


L'évaluation du développement du jeune enfant doit prendre en compte la détection des troubles neurodéveloppementaux et notamment celle des troubles du spectre autistique. Face à un retard de développement du langage à 18 mois ou face à un défaut de contact social, cette hypothèse doit être considérée afin de réaliser une évaluation plus approfondie. Nous donnons quelques repères cliniques ainsi que les signes précurseurs afin de permettre le cas échéant une prise en charge la plus précoce possible. Ceci permettra souvent une évolution plus favorable avec l'objectif de réduire le déficit mental et de permettre le développement des compétences spécifiques de l'enfant.


Assuntos
Transtorno do Espectro Autista/diagnóstico , Diagnóstico Precoce , Humanos
7.
J Biol Regul Homeost Agents ; 28(3): 489-95, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25316136

RESUMO

Rough titanium surfaces enhance the activation of Wnt canonical signaling, a pathway required for osteoblast differentiation. The present study investigated the effects of GSK3b-inhibitor (2'Z,3'E)- 6-Bromoindirubin-3'-oxime (BIO) on osteoblastic differentiation on titanium surfaces with different topography and wettability. C2C12 cells were plated on pickled, acid-etched/sand-blasted (SLA), modified hydrophilic SLA titanium discs (modSLA) and stimulated with increasing doses of BIO. Activation of Wnt canonical signaling was measured with a reporter system. Gene expression was measured in the same cell system by Real Time PCR. Osteoblastic MC3T3 cells were then plated on discs with or without BIO and the expression of osteoblast specific genes was assessed by Real Time PCR. One mM BIO activated Wnt canonical signaling in C2C12 cells on all surfaces, and the highest effect was on rough surfaces. BIO markedly increased the expression of Osteoprotegerin and Osteocalcin in MC3T3 cells on rough surfaces at the concentration of 100 nM, and on all surfaces at the concentration of 1 mM. BIO enhances Wnt signaling activation and the expression of osteoblastic genes on rough surfaces and could be a viable approach to improve cell response to implant surfaces.


Assuntos
Inibidores Enzimáticos/farmacologia , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Osteoblastos/enzimologia , Titânio/química , Via de Sinalização Wnt , Animais , Diferenciação Celular , Linhagem Celular , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Glicogênio Sintase Quinase 3 beta , Camundongos , Osteoblastos/citologia , Osteocalcina/biossíntese , Osteoprotegerina/biossíntese , Propriedades de Superfície
8.
J Endocrinol Invest ; 37(7): 609-17, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24696159

RESUMO

BACKGROUND: Vitamin D deficiency is common in the general population and may impair skeletal muscle function. Very few data are available regarding this condition in professional athletes. AIM: To evaluate some skeletal parameters and in particular serum 25-hydroxyvitamin D status in professional rugby players during two different sunlight exposure times (October and early April) and to assess its impact on bone metabolism. MATERIALS AND METHODS: Twenty-one male healthy professional rugby players living in northern Italy at latitude of 44°55'N (age 24.6 ± 4.3 years; height 182.0 ± 0.05 cm; mass 96.3 ± 14.6 kg; BMI 28.9 ± 3.7 kg/m(2)) participated in this observational study. During 2012/2013 Italian rugby season, 25-hydroxyvitamin D, PTH and other related biochemical parameters were monitored. Dietary calcium intake and body composition by DXA were also evaluated. RESULTS: Significant changes were observed between October and April data for 25-hydroxyvitamin D concentration (22.8 ± 5.8 vs. 19.1 ± 5.3 ng/ml; p = 0.001) whereas serum PTH, calcium and phosphorus plasma levels did not change. They presented with an appropriate daily intake of calcium (1,304.8 ± 477.9 mg; max 1,939 mg; min 228 mg). CONCLUSIONS: Professional rugby athletes practicing a sport characterized by intense outdoor training and with good calcium intake are at higher risk of hypovitaminosis D that worsens significantly during times of low cutaneous vitamin D production. Further studies are warranted to evaluate whether an appropriate supplementation with cholecalciferol in professional athletes is needed.


Assuntos
Futebol Americano , Deficiência de Vitamina D/diagnóstico , Vitamina D/análogos & derivados , Adulto , Composição Corporal , Cálcio da Dieta , Humanos , Itália , Masculino , Estações do Ano , Vitamina D/sangue , Deficiência de Vitamina D/sangue , População Branca , Adulto Jovem
9.
J Biomed Mater Res A ; 102(11): 3855-61, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24323594

RESUMO

Periostin is a matricellular protein highly expressed in periodontal ligament and periostium and has been shown to be required for tissue development and maintenance. We showed that the adhesion of murine osteoblastic MC3T3 cells to thiolated hyaluronic acid/polyethyleneglycol hydrogels was greatly improved by enrichment with periostin. Polished or sand-blasted/acid-etched (SLA) commercially pure titanium surfaces were also coated with this protein and periostin ameliorated cell adhesion and dramatically affected cell morphology on both surfaces, as assessed at fluorescence microscopy, scanning electron microscopy, and chemiluminescence-based viability assay. Moreover, periostin increased the expression of alkaline phosphatase, osteoprotegerin, connective tissue growth factor, collagen 1a1, osteocalcin, Runx2, and osterix transcription factors on smooth surfaces. However, it did not affect, or even decreased, the expression of these genes on SLA discs. Transcript levels for connexin 43 were greatly increased on both surfaces in the presence of periostin. Taken together, these results show that periostin coatings can be a viable approach to improve cell adhesion and differentiation on implantable biomaterials.


Assuntos
Moléculas de Adesão Celular/química , Diferenciação Celular , Materiais Revestidos Biocompatíveis/química , Osteoblastos/metabolismo , Próteses e Implantes , Titânio/química , Animais , Antígenos de Diferenciação/biossíntese , Adesão Celular , Humanos , Ácido Hialurônico/química , Hidrogéis/química , Teste de Materiais/métodos , Camundongos , Osteoblastos/citologia , Polietilenoglicóis/química
10.
Clin Oral Implants Res ; 24(8): 921-7, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22626030

RESUMO

AIMS: Promoting bone formation at the tissue interface is an important step to improve implant success. This study investigated whether stimulation of Wnt signaling by GSK3b inhibitor lithium chloride (LiCl) could affect the response of mesenchymal or osteoblastic cells growing on titanium surfaces with different topography and wettability, and improve their differentiation along the osteoblastic lineage. MATERIAL AND METHODS: Murine mesenchymal C2C12 cells were plated on Pickled, acid-etched/sand-blasted (SLA), and hydrophilic SLA titanium disks (modSLA) and stimulated with increasing doses of LiCl. Cell viability was measured using chemiluminescence-based ATP quantitation and activation of Wnt canonical signaling was measured using a Luciferase-based reporter assay. Gene expression was measured using real time PCR in C2C12 cells, murine osteoblastic MC3T3 cells or murine primary bone marrow cells. RESULTS: LiCl stimulated Wnt activation and expression of Wnt markers in C2C12 cells on modSLA. Addition of 1 mM LiCl increased levels for bone marker Osteocalcin in MC3T3 cells on modSLA surfaces. Similarly, LiCl potently enhanced Osteoprotegetrin levels in MC3T3 cells on modSLA. When primary bone marrow cells were stimulated with LiCl, the expression of Wnttarget genes and osteoblastic differentiation markers was increased on modSLA surfaces. CONCLUSIONS: Stimulation of the canonical Wnt pathway promoted osteoblast differentiation on hydrophilic modSLA surfaces. Taken together, these results demonstrate that Wnt activators such as LiCl should be further tested as a possible approach to improve implant osseointegration.


Assuntos
Materiais Dentários/química , Quinase 3 da Glicogênio Sintase/antagonistas & inibidores , Cloreto de Lítio/farmacologia , Osteoblastos/efeitos dos fármacos , Titânio/química , Via de Sinalização Wnt/efeitos dos fármacos , Células 3T3 , Condicionamento Ácido do Dente/métodos , Fosfatase Alcalina/análise , Animais , Células da Medula Óssea/efeitos dos fármacos , Técnicas de Cultura de Células , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Linhagem da Célula/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Corrosão Dentária/métodos , Glicogênio Sintase Quinase 3 beta , Interações Hidrofóbicas e Hidrofílicas , Luciferases , Luminescência , Substâncias Luminescentes , Camundongos , Células Musculares/efeitos dos fármacos , Osteocalcina/efeitos dos fármacos , Osteoprotegerina/efeitos dos fármacos , Propriedades de Superfície , Molhabilidade
11.
Eur Cell Mater ; 24: 46-59, 2012 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-22791372

RESUMO

Endosseous implants are important tools to replace missing teeth or damaged tissue segments. Their clinical success depends on their integration in bone and, thus, on the response of bone cells to material and surface characteristics. Recent evidence has shown that surface topography and chemistry affect WNT signalling, a pivotal pathway for the commitment of mesenchymal progenitors to the osteoblast lineage and for bone homeostasis. WNT signalling comprises several cascades that, acting through different effectors, modulate several aspects of cell behaviour. It has been shown that cells growing on rough titanium surfaces display a different expression profile for WNT factors, and that surface features can alter the response of bone cells to WNT factors. Although the underlying mechanisms to this regulation are still poorly understood, the present review reports intriguing evidence that that cell cytoskeletal signalling is involved in activating WNT signalling in cells growing on rough implant surfaces.


Assuntos
Osso e Ossos/metabolismo , Células-Tronco Mesenquimais/metabolismo , Osseointegração/fisiologia , Osteoblastos/metabolismo , Via de Sinalização Wnt/fisiologia , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Implantação Dentária Endóssea/métodos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Osseointegração/efeitos dos fármacos , Osteoblastos/citologia , Osteoblastos/efeitos dos fármacos , Propriedades de Superfície , Titânio/química , Titânio/farmacologia , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
12.
Acta Biomater ; 8(8): 2963-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22564787

RESUMO

Surface topography affects cell function and differentiation. It has been previously shown that rough surfaces can enhance the activation of canonical Wnt signaling, an important pathway for osteoblast differentiation and bone maintenance, but the underlying mechanisms are still poorly understood. The present paper investigates whether cytoskeletal organization contributes to regulating this pathway. Rho-associated protein kinase (ROCK), an important controller of actin microfilaments, was inhibited with 2mM specific antagonist Y-27632 in mesenchymal and osteoblastic cells growing on titanium discs with a polished or acid-etched, sand-blasted (SLA) surface. Y-27632 subverted the morphology of the cytoskeleton on polished and, to a lesser extent, on SLA surfaces, as evidenced by fluorescence microscopy. Although ROCK inhibition did not affect cell viability, it increased activation of Wnt signaling in uncommitted C2C12 mesenchymal cells on polished surfaces but not on SLA discs upon reporter assay. Consistently with this, real-time polymerase chain reaction analysis showed that MC3T3 cells on polished surfaces expressed higher mRNA levels for ß-catenin and alkaline phosphatase, a known Wnt target gene, and for the osteoblastic differentiation marker osteocalcin after ROCK inhibition. Taken together, these data demonstrate that cytoskeletal organization mediates activation of Wnt canonical signaling in cells on titanium surfaces with different topographies.


Assuntos
Citoesqueleto de Actina/metabolismo , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Próteses e Implantes , Titânio/farmacologia , Via de Sinalização Wnt , Citoesqueleto de Actina/efeitos dos fármacos , Actinas/metabolismo , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Amidas/farmacologia , Animais , Diferenciação Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Imunofluorescência , Regulação da Expressão Gênica/efeitos dos fármacos , Luciferases/metabolismo , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Osteocalcina/genética , Osteocalcina/metabolismo , Osteoprotegerina/genética , Osteoprotegerina/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Piridinas/farmacologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Propriedades de Superfície/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , beta Catenina/genética , beta Catenina/metabolismo , Quinases Associadas a rho/antagonistas & inibidores , Quinases Associadas a rho/metabolismo
13.
J Endocrinol Invest ; 34(11): e386-91, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21750394

RESUMO

The aim of the study was to estimate the absolute risk of fracture in a sample of postmenopausal women with the Italian version of FRAX®, using femoral neck bone mineral density (BMD) and 3 internationally validated clinical risk factors (CRFs) (history of fragility fracture, family history of hip fracture, current smoking). We retrospectively studied 9586 women (mean age 64.1 yr) examined in three osteoporosis centers from Northern Italy over two years (2001-2002). The risk of major osteoporotic (clinical spine, hip, forearm and humerus) and hip fractures was estimated using the online version of the FRAX algorithm adapted for Italy. The median 10-year risk was 7.5% for osteoporotic fracture and 1.7% for hip fracture. 25% of subjects had a 10-year risk ≥ 12.1% for osteoporotic fracture and ≥ 4.1% for hip fracture. The median 10-year risk of fracture increased with the number of prevalent CRFs. For major osteoporotic fractures risk rose from 6.3% to 10.9%, 21.4% and 40.9% with 1, 2 and 3 prevalent CRFs, respectively. For hip fractures the corresponding figures were: 1.3%, 2.7%, 7.0% and 21.9%, respectively. However, it must be emphasized that in 2 out of 3 women, none of the CRFs examined was present and the assessment of risk was limited to age and BMD. Our data provide the first description of the effect of the combination of BMD, age and CRFs on fracture risk stratification in a large sample of Italian postmenopausal women using FRAX®. The results are a useful starting point to define criteria for the application of FRAX® in clinical practice in Italy.


Assuntos
Colo do Fêmur , Osteoporose Pós-Menopausa/diagnóstico , Osteoporose Pós-Menopausa/epidemiologia , Fraturas por Osteoporose/diagnóstico , Fraturas por Osteoporose/epidemiologia , Idoso , Idoso de 80 Anos ou mais , Densidade Óssea/fisiologia , Estudos Transversais , Feminino , Colo do Fêmur/lesões , Colo do Fêmur/patologia , Fraturas do Quadril/diagnóstico , Fraturas do Quadril/epidemiologia , Fraturas do Quadril/etiologia , Humanos , Itália/epidemiologia , Pessoa de Meia-Idade , Osteoporose Pós-Menopausa/complicações , Fraturas por Osteoporose/etiologia , Estudos Retrospectivos , Medição de Risco/métodos , Medição de Risco/tendências , Fatores de Risco
14.
J Dent Res ; 90(3): 360-4, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21297018

RESUMO

Little is known about how surface topography can modulate mesenchymal cell responses to oxygen-related stress occurring with age, or during the early phases of wound healing or inflammation. To antagonize Reactive Oxygen Species (ROS), cells resort to defense mechanisms, relying on ß-catenin, a molecular switch between a TCF-mediated pathway, which promotes cells proliferation and commitment, and an alternative one controlled by FoxO, which induces quiescence and defenses against ROS. In the present study, we show that mesenchymal C2C12 cells are protected from H2O2-induced oxidative stress when they grow on rough (SLA) titanium surfaces. The expression of anti-ROS genes and FoxO/ß-catenin signaling, as measured by a reporter assay, were increased on SLA surfaces. We also show that TCF-mediated transcription was inhibited by ROS in cells growing on either smooth or SLA titanium. Our results demonstrate that surface topography modulates cell resistance to ROS and the balance between the molecular pathways regulating cell growth and cell defense against oxidative stress.


Assuntos
Fatores de Transcrição Forkhead/genética , Células-Tronco Mesenquimais/metabolismo , Estresse Oxidativo/fisiologia , Titânio , beta Catenina/genética , Animais , Linhagem Celular , Fatores de Transcrição Forkhead/metabolismo , Peróxido de Hidrogênio/farmacologia , Células-Tronco Mesenquimais/efeitos dos fármacos , Camundongos , Oxidantes/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/fisiologia , Superóxido Dismutase/metabolismo , Propriedades de Superfície , Fatores de Transcrição TCF/genética , Fatores de Transcrição TCF/metabolismo , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
15.
J Periodontal Res ; 46(4): 397-406, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21332475

RESUMO

BACKGROUND AND OBJECTIVE: Chronic periodontitis is a widespread disease affecting tooth-supporting structures that can lead to extensive loss of periodontal ligament and bone, ultimately resulting in tooth loss. Extensive evidence has demonstrated a strong association between age, metabolic disorders such as type II diabetes, oxidative stress and alveolar bone loss. The molecular players controlling bone maintenance and underlying age-related bone loss and its links to the general metabolism are currently the object of intense research. MATERIAL AND METHODS: Recent findings are summarized to elucidate the molecular mechanisms linking oxidative stress, bone loss and metabolic factors. RESULTS: It is well known that reactive oxygen species are an inevitable consequence of cellular respiration and that organisms have developed an efficient array of defenses against them. The core of this complex defense line is a family of transcription factors, known as FoxOs, which can bind to ß-catenin and initiate a transcriptional programme regulating cell apoptosis, DNA repair and degradation of reactive oxygen species. An increase in reactive oxygen species due, for example, to age or insulin resistance, generates a situation in which bone formation is impaired by activation of FoxO, and a decrease in Wnt signaling and bone resorption are promoted. CONCLUSION: The balance between FoxO and the Wnt pathway is finely tuned by systemic and local factors, creating a far-reaching mechanism that dictates the fate of mesenchymal progenitors and regulates the homeostasis of bone, providing a rationale for the impairment of systemic and alveolar bone maintenance clinically observed with age and metabolic diseases.


Assuntos
Perda do Osso Alveolar/etiologia , Periodontite Crônica/etiologia , Fatores de Transcrição Forkhead/fisiologia , Estresse Oxidativo/fisiologia , Proteínas Wnt/fisiologia , Humanos , Peroxidação de Lipídeos/fisiologia , Proteínas Proto-Oncogênicas c-akt/fisiologia , Espécies Reativas de Oxigênio/metabolismo , beta Catenina/fisiologia
16.
Blood Cancer J ; 1(6): e27, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22829171

RESUMO

Wingless-type (Wnt) signaling through the secretion of Wnt inhibitors Dickkopf1, soluble frizzled-related protein-2 and -3 has a key role in the decreased osteoblast (OB) activity associated with multiple myeloma (MM) bone disease. We provide evidence that another Wnt antagonist, sclerostin, an osteocyte-expressed negative regulator of bone formation, is expressed by myeloma cells, that is, human myeloma cell lines (HMCLs) and plasma cells (CD138+ cells) obtained from the bone marrow (BM) of a large number of MM patients with bone disease. We demonstrated that BM stromal cells (BMSCs), differentiated into OBs and co-cultured with HMCLs showed, compared with BMSCs alone, reduced expression of major osteoblastic-specific proteins, decreased mineralized nodule formation and attenuated the expression of members of the activator protein 1 transcription factor family (Fra-1, Fra-2 and Jun-D). Moreover, in the same co-culture system, the addition of neutralizing anti-sclerostin antibodies restored OB functions by inducing nuclear accumulation of ß-catenin. We further demonstrated that the upregulation of receptor activator of nuclear factor κ-B ligand and the downregulation of osteoprotegerin in OBs were also sclerostin mediated. Our data indicated that sclerostin secretion by myeloma cells contribute to the suppression of bone formation in the osteolytic bone disease associated to MM.

17.
J Dent Res ; 89(4): 331-43, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20200416

RESUMO

Mechanical loading is of pivotal importance in the maintenance of skeletal homeostasis, but the players involved in the transduction of mechanical stimuli to promote bone maintenance have long remained elusive. Osteocytes, the most abundant cells in bone, possess mechanosensing appendices stretching through a system of bone canaliculi. Mechanical stimulation plays an important role in osteocyte survival and hence in the preservation of bone mechanical properties, through the maintenance of bone hydratation. Osteocytes can also control the osteoblastic differentiation of mesenchymal precursors in response to mechanical loading by modulating WNT signaling pathways, essential regulators of cell fate and commitment, through the protein sclerostin. Mutations of Sost, the sclerostin-encoding gene, have dramatic effects on the skeleton, indicating that osteocytes may act as master regulators of bone formation and localized bone remodeling. Moreover, the development of sclerostin inhibitors is opening new possibilities for bone regeneration in orthopedics and the dental field.


Assuntos
Remodelação Óssea/fisiologia , Mecanotransdução Celular/fisiologia , Osteócitos/fisiologia , Osteogênese/fisiologia , Proteínas Wnt/metabolismo , Animais , Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas Morfogenéticas Ósseas/genética , Proteínas Morfogenéticas Ósseas/metabolismo , Análise do Estresse Dentário , Regulação da Expressão Gênica no Desenvolvimento , Humanos , Odontogênese/genética , Odontogênese/fisiologia , Osteogênese/genética , Estresse Mecânico , Proteínas Wnt/antagonistas & inibidores , Proteínas Wnt/genética , beta Catenina/metabolismo
18.
Exp Gerontol ; 43(2): 61-5, 2008 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17870272

RESUMO

Recent observations indicate that immunosenescence is not accompanied by an unavoidable and progressive deterioration of the immune function, but is rather the result of a remodeling where some functions are reduced, others remain unchanged or even increased. In addition, it appears that the ancestral/innate compartment of the immune system is relatively preserved during aging in comparison to the more recent and sophisticated adaptive compartment that exhibit more profound modifications. The T-cell branch displays an age-dependent decline of the absolute number of total T-cells (CD3+), involving both CD4+ and CD8+ subsets, accompanied by an increase of NK cells with well-preserved cytotoxic function and by a reduction of B-cells. One of the main characteristics of the immune system during aging is a progressive, age-dependent decline of the virgin T-cells (CD95-), which is particularly profound at the level of the CD8+ subpopulation of the oldest old subjects. The progressive exhaustion of this important T-cell subpopulation dedicated primarily to the defense against new antigenic challenges (viral, neoplastic, bacterial ones), could be a consequence of both the thymic involution and the lifelong chronic antigenic stimulation. The immune function of the elderly, is therefore weakened by the exhaustion of CD95- virgin cells that are replaced by large clonal expansions of CD28- T-cells. The origin of CD28- cells has not been completely clarified yet, but it is assumed that they represent cells in the phase of replicative senescence characterized by shortening telomers and reduced proliferative capacity. A major characteristic of the immune system during aging is the up-regulation of the inflammatory responses which appears to be detrimental for longevity. In this regard, we have recently observed a progressive age-dependent increase of type 1(IL-2, IFN-gamma, TNF-alpha) and type 2 (IL-4, IL-6, IL-10) positive CD8+ T-cells; in particular, type 1 cytokine-positive cells significantly increased, with age, in all CD8+ subsets particularly among effector/cytotoxic and memory cells. A major force able to drive a chronic pro-inflammatory state during aging may be represented by persistent viral infections by EBV and CMV. Therefore, we have determined the frequency and the absolute number of viral antigen-specific CD8+ T-cells in subjects older than 85 years, who were serologically positive for CMV or EBV. In the majority of these subjects we detected the presence of T lymphocytes positive for epitopes of CMV or EBV. In all subjects the absolute number of CMV-positive CD8+ cells outnumbered that of EBV-positive ones. In addition, the majority of CMV+ T cells were included within the CD28- subpopulation, while EBV+ T cells belonged mainly to the CD28+ subset. These data indicate that the chronic antigenic stimulation induced by persistent viral infections during aging bring about important modifications among CD8+ subsets, which are particularly evident in the presence of CMV persistence. The age-dependent expansions of CD8+CD28- T-cells, mostly positive for pro-inflammatory cytokines and including the majority of CMV-epitope-specific cells, underlines the importance of chronic antigenic stimulation in the pathogenesis of the main immunological alterations of aging and may favour the appearance of several pathologies (arteriosclerosis, dementia, osteoporosis, cancer) all of which share an inflammatory pathogenesis.


Assuntos
Sistema Imunitário/fisiologia , Longevidade/imunologia , Idoso de 80 Anos ou mais , Linfócitos T CD8-Positivos/imunologia , Citocinas/fisiologia , Feminino , Humanos , Memória Imunológica , Inflamação , Ativação Linfocitária , Masculino
19.
Biochim Biophys Acta ; 1568(1): 99-104, 2001 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-11731091

RESUMO

The oxidative action of acetylphenylhydrazine (APH) on red blood cells obtained from healthy donors and from patients with breast cancer has been investigated by Mössbauer spectroscopy. Whole blood was incubated with APH for different time periods and the Mössbauer spectra of the packed red cells were recorded and compared. The evolution with time of the oxidation products has been followed. The largest difference in red cells analysis between healthy persons and patients was found after about 50 min of treatment where Mössbauer spectra of patient samples show a much broader spectral pattern due to an advanced haemoglobin oxidation.


Assuntos
Neoplasias da Mama/sangue , Eritrócitos/efeitos dos fármacos , Hemoglobinas/metabolismo , Oxidantes , Fenil-Hidrazinas , Eritrócitos/metabolismo , Feminino , Hemina/análise , Hemoglobinas/análise , Humanos , Metemoglobina/análise , Oxirredução , Oxiemoglobinas/análise , Espectroscopia de Mossbauer , Fatores de Tempo
20.
Exp Gerontol ; 36(3): 547-57, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11250125

RESUMO

Growing evidence suggests that interleukin-6 (IL-6) may play a pathogenetic role in postmenopausal bone loss and in other age-related pathological conditions. In this study, we have examined the age-related changes in the serum levels of IL-6 and the soluble receptors that modulate its biological activity--soluble IL-6 receptor (sIL-6R) and soluble gp130 (sgp130)--in 220 women (from 25 to 104yr old), including 22 centenarians. Serum IL-6 rose exponentially with age (r=0.74, p<0.0001). The median level of IL-6 increased almost ten-fold with age, from 1.16pg/ml in premenopausal women to 10.27pg/ml in centenarians. Serum sIL-6R and sgp130 showed an increase until the seventh decade and a progressive decrease in older ages (r=0.39, p<0.0001 and r=0.26, p=0.008, respectively). IL-6, sIL-6R and sgp130 were significantly higher in women within 10yr of menopause as compared to premenopausal subjects (1.51 vs. 1.16pg/ml, p=0.012; 41.9 vs. 35.7ng/ml, p=0.002; and 253.4 vs. 230.7ng/ml, p=0.008, respectively). In postmenopausal women, a negative correlation was found between sIL-6R and the lumbar bone mineral density (BMD) (r=-0.28, p=0.002) even after adjusting for age and weight. Furthermore, sIL-6R levels were higher in osteoporotic compared to normal women (47.9 vs. 39.5ng/ml, p=0.001). In conclusion, our results show that the serum levels of IL-6, sIL-6R and sgp130 exhibit different patterns of age- and menopause-related changes, and that the biological activity of IL-6 may be increased with age with potential implications in the age-related diseases such as osteoporosis.


Assuntos
Envelhecimento/sangue , Interleucina-6/sangue , Menopausa/sangue , Moléculas de Adesão de Célula Nervosa/sangue , Receptores de Interleucina-6/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/imunologia , Contactinas , Feminino , Humanos , Menopausa/imunologia , Pessoa de Meia-Idade , Pós-Menopausa/sangue , Pós-Menopausa/imunologia , Pré-Menopausa/sangue , Pré-Menopausa/imunologia , Análise de Regressão
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