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1.
J Cell Physiol ; 227(6): 2461-9, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21830213

RESUMO

Synovial fibroblasts (SFs) contribute to the development of osteoarthritis (OA) by the secretion of a wide range of pro-inflammatory mediators, including cytokines and lipid mediators of inflammation. Previous studies suggest that electromagnetic fields (EMFs) may represent a potential therapeutic approach to limit cartilage degradation and control inflammation associated to OA, and that they may act through the adenosine pathway. Therefore, we investigated whether EMFs might modulate inflammatory activities of human SFs from OA patients (OASFs) treated with interleukin-1ß (IL-1ß), and the possible involvement of adenosine receptors (ARs) in mediating EMF effects. EMF exposure induced a selective increase in A(2A) and A(3) ARs. These increases were associated to changes in cAMP levels, indicating that ARs were functionally active also in EMF-exposed cells. Functional data obtained in the presence of selective A(2A) and A(3) adenosine agonists and antagonists showed that EMFs inhibit the release of prostaglandin E(2) (PGE(2)) and the proinflammatory cytokines interleukin-6 (IL-6) and interleukin-8 (IL-8), while stimulating the release of interleukin-10 (IL-10), an antinflammatory cytokine. These effects seem to be mediated by the EMF-induced upregulation of A(2A) and A(3) ARs. No effects of EMFs or ARs have been observed on matrix degrading enzyme production. In conclusion, this study shows that EMFs display anti-inflammatory effects in human OASFs, and that these EMF-induced effects are in part mediated by the adenosine pathway, specifically by the A(2A) and A(3) AR activation. Taken together, these results open new clinical perspectives to the control of inflammation associated to joint diseases.


Assuntos
Citocinas/metabolismo , Dinoprostona/metabolismo , Campos Eletromagnéticos , Fibroblastos/metabolismo , Mediadores da Inflamação/metabolismo , Osteoartrite do Quadril/metabolismo , Receptores Purinérgicos P1/metabolismo , Membrana Sinovial/metabolismo , Proteínas ADAM/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Células Cultivadas , AMP Cíclico/metabolismo , Relação Dose-Resposta a Droga , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/imunologia , Fibroblastos/patologia , Humanos , Interleucina-10/metabolismo , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Masculino , Metaloproteinases da Matriz/metabolismo , Pessoa de Meia-Idade , Osteoartrite do Quadril/genética , Osteoartrite do Quadril/imunologia , Osteoartrite do Quadril/patologia , Agonistas do Receptor Purinérgico P1/farmacologia , Antagonistas de Receptores Purinérgicos P1/farmacologia , RNA Mensageiro/metabolismo , Receptor A2A de Adenosina/metabolismo , Receptor A3 de Adenosina/metabolismo , Receptores Purinérgicos P1/efeitos dos fármacos , Receptores Purinérgicos P1/genética , Membrana Sinovial/efeitos dos fármacos , Membrana Sinovial/imunologia , Membrana Sinovial/patologia
2.
Osteoarthritis Cartilage ; 17(2): 252-62, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-18640059

RESUMO

OBJECTIVE: To investigate the role of adenosine analogs and electromagnetic field (EMF) stimulation on prostaglandin E(2) (PGE(2)) release and cyclooxygenase-2 (COX-2) expression in bovine synovial fibroblasts (SFs). METHODS: SFs isolated from synovia were cultured in monolayer. Saturation and binding experiments were performed by using typical adenosine agonists: N6-cyclohexyladenosine (CHA, A(1)), 2-[p-(2-carboxyethyl)-phenetyl-amino]-5'-N-ethylcarboxamidoadenosine (CGS 21680, A(2A)), 5'-N-ethylcarboxamidoadenosine (NECA, non-selective), N6-(3-iodobenzyl)2-chloroadenosine-5'-N-methyluronamide (Cl-IB-MECA, A(3)). SFs were treated with TNF-alpha (10 ng/ml) and lipopolysaccharide (LPS) (1 microg/ml) to activate inflammatory response. Adenosine analogs were added to control and TNF-alpha- or LPS-treated cultures both in the absence and in the presence of adenosine deaminase (ADA) which is used to deplete endogenous adenosine. Parallel cultures were exposed to EMFs (75 Hz, 1.5 mT) during the period in culture (24h). PGE(2) release was measured by immunoassay. COX-2 expression was evaluated by RT-PCR. RESULTS: TNF-alpha and LPS stimulated PGE(2) release. All adenosine agonists, except for Cl-IB-MECA, significantly inhibited PGE(2) production. EMFs inhibited PGE(2) production in the absence of adenosine agonists and increased the effects of CHA, CGS 21680 and NECA. In ADA, the inhibition on PGE(2) release induced by CHA, CGS and NECA was stronger than in the absence of ADA and the EMF-inhibitory effect was lost. Changes in PGE(2) levels were associated to modification of COX-2 expression. CONCLUSIONS: This study supports anti-inflammatory activities of A(1) and A(2A) adenosine receptors and EMFs in bovine SFs. EMF activity appears mediated by an EMF-induced up-regulation of A(2A) receptors. Biophysical and/or pharmacological modulation of adenosine pathways may play an important role to control joint inflammation.


Assuntos
Adenosina/agonistas , Dinoprostona/metabolismo , Campos Eletromagnéticos , Fibroblastos/metabolismo , Líquido Sinovial/metabolismo , Adenosina/farmacologia , Animais , Ligação Competitiva , Bovinos , Células Cultivadas , Colforsina/farmacologia , Ciclo-Oxigenase 2/metabolismo , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Lipopolissacarídeos/farmacologia , Receptores Purinérgicos P1/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Líquido Sinovial/citologia , Líquido Sinovial/efeitos dos fármacos , Fator de Necrose Tumoral alfa/farmacologia
3.
J Neural Transm (Vienna) ; 116(3): 257-65, 2009 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-19189041

RESUMO

Behavioral and neurophysiological changes have been reported after exposure to extremely low frequency magnetic fields (ELF-MF) both in animals and in humans. The physiological bases of these effects are still poorly understood. In vitro studies analyzed the effect of ELF-MF applied in pulsed mode (PEMFs) on neuronal cultures showing an increase in excitatory neurotransmission. Using transcranial brain stimulation, we studied noninvasively the effect of PEMFs on several measures of cortical excitability in 22 healthy volunteers, in 14 of the subjects we also evaluated the effects of sham field exposure. After 45 min of PEMF exposure, intracortical facilitation produced by paired pulse brain stimulation was significantly enhanced with an increase of about 20%, while other parameters of cortical excitability remained unchanged. Sham field exposure produced no effects. The increase in paired-pulse facilitation, a physiological parameter related to cortical glutamatergic activity, suggests that PEMFs exposure may produce an enhancement in cortical excitatory neurotransmission. This study suggests that PEMFs may produce functional changes in human brain.


Assuntos
Encéfalo/fisiologia , Campos Eletromagnéticos , Potenciais Evocados/fisiologia , Estimulação Magnética Transcraniana , Adulto , Mapeamento Encefálico/métodos , Eletroencefalografia , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Tempo de Reação/fisiologia , Estimulação Magnética Transcraniana/métodos , Adulto Jovem
4.
Biomed Pharmacother ; 60(8): 458-62, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16930935

RESUMO

Electrochemotherapy (ECT) is a new treatment for metastatic nodules of solid tumors on the skin or subcutaneous tissue. ECT is a combination of a physical effect, cell membrane poration, and cytotoxic drug administration. Cell membrane poration is achieved by applying short intense electric filed pulses. Pore formation on the cell membrane allows low permeant drugs like bleomycin or cisplatin to enter the cell and thus locally increase their toxicity: up to 10.000 times for bleomycin and 80 times for cisplatin. ECT has been investigated in a multicenter study European Standard Operating Procedures for Electrochemotherapy (ESOPE) that demonstrates how by ECT over 80% of the cutaneous or subcutaneous metastatic nodules can be healed, thus confirming the results of previous studies. ECT efficacy is independent of tumor histology. The experience gathered in the ESOPE study allowed to prepare standard operating procedures that are key to the dissemination of the technology. ECT is safe effective, the treatment is completed in one session usually on an out-patient basis with minimum side-effects. ECT is cost-effective and, although palliative, it ameliorates patients' quality of life. ECT is the treatment of choice for tumors refractory to conventional treatment, can be used in form of cytoreductive therapy before conventional treatment for organ sparing and functions saving, finally can be adopted to treat hemorrhagic or painful nodules, it can be applied in previously irradiated areas.


Assuntos
Eletroquimioterapia , Neoplasias Cutâneas/tratamento farmacológico , Neoplasias Cutâneas/secundário , Animais , Antineoplásicos/uso terapêutico , Bleomicina/uso terapêutico , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Ensaios Clínicos como Assunto , Ensaios de Seleção de Medicamentos Antitumorais , Humanos
5.
J Bone Joint Surg Br ; 88(1): 123-8, 2006 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-16365135

RESUMO

We investigated the effect of stimulation with a pulsed electromagnetic field on the osseointegration of hydroxyapatite in cortical bone in rabbits. Implants were inserted into femoral cortical bone and were stimulated for six hours per day for three weeks. Electromagnetic stimulation improved osseointegration of hydroxyapatite compared with animals which did not receive this treatment in terms of direct contact with the bone, the maturity of the bone and mechanical fixation. The highest values of maximum push-out force (F(max)) and ultimate shear strength (sigma(u)) were observed in the treated group and differed significantly from those of the control group at three weeks (F(max); p < 0.0001; sigma(u), p < 0.0005).


Assuntos
Durapatita/química , Campos Eletromagnéticos , Prótese Articular , Osseointegração , Animais , Fenômenos Biomecânicos , Diáfises/patologia , Fêmur/patologia , Prótese de Quadril , Masculino , Teste de Materiais/métodos , Coelhos , Resistência ao Cisalhamento
6.
Cancer Res ; 36(12): 4631-8, 1976 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-1069607

RESUMO

Time course and "chase" experiments showed that, after incubation of acute myeloid leukemia blast cells with a labeled RNA precursor, a large proportion of radioactivity remained associated with RNA molecules larger than 45 S even after several hr. Double-labeling experiments with [5-3H]uridine and [methyl-14C]methionine indicated that unmethylated giant heterogeneous RNA larger than 45 S is processed much more slowly than the 45 S ribosomal precursor, so that relatively large amounts of fairly stable RNA of the former class accumulate in the cell. The measurement of labeled giant heterogeneous RNA molecules bound to polyuridylate-fiberglass filters showed that molecules carrying polyadenylate segments seemingly turn over faster than those lacking polyadenylate.


Assuntos
Leucemia Mieloide Aguda/metabolismo , Ativação Linfocitária , RNA Neoplásico/metabolismo , Dactinomicina/farmacologia , Humanos , Cinética , Linfócitos/metabolismo , Peso Molecular , Poli A/análise , Poli A/metabolismo , RNA Ribossômico/metabolismo
7.
Cancer Res ; 37(8 Pt 1): 2667-72, 1977 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-68812

RESUMO

Whole-cell RNA, extracted from acute myeloid leukemia blast cells, was fractionated by sedimentation through sucrose gradients. The proportion of double-helical segments present in each fraction was then determined by a quantitative microcomplement fixation assay that specifically measures double-helical RNA. Sizable amounts of double-helical segments were detected in all fractions of cellular RNA corresponding to S values higher than approximately 20. In all cell populations examined the highest proportion of double-helical segments was found in RNA fractions sedimenting faster then the 45 S ribosomal precursors RNA, i.e., in fractions including only heterogeneous nuclear RNA.


Assuntos
Leucemia Mieloide Aguda/análise , RNA Neoplásico/análise , Especificidade de Anticorpos , Antígenos de Neoplasias , Núcleo Celular/análise , Centrifugação com Gradiente de Concentração , Testes de Fixação de Complemento , Eletroforese em Gel de Poliacrilamida , Epitopos , Humanos , Imunoglobulina G , Microquímica , Peso Molecular , Conformação de Ácido Nucleico , RNA Neoplásico/imunologia
8.
Biochim Biophys Acta ; 561(2): 301-11, 1979 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-427158

RESUMO

Human DNA isolated from normal phytohaemagglutinin-stimulated human lymphocytes and from acute leukemia blast cells have been studied by renaturation techniques using hydroxyapatite binding and DNA hyperchromism. In the leukemic genome, the unique sequences account for 62% of the genome of leukemic DNA. Repetitive sequences may be subdivided into at least three fractions: (a) foldback sequences, which represent 5% of the genome; (b) sequences with high repetition frequency (3. 10(4) times on the average), which represent 12% of the genome; (c) sequences with low repetition frequency (10 times on the average), which represent 16% of the genome. The average length of the repetitive sequences is evaluated to be between 200 and 500 nucleotides. There are at least two patterns of interspersion of repetitive sequences with unique sequences of different length: short (about 2000 nucleotides on average) and long (not defined). The results of our experiments on DNA from normal phytohaemagglutinin-stimulated human lymphocytes are in close agreement with those reported by other authors studying different types of human cells. The human leukemic DNA, as far as the parameters that have been studied, does not significantly differ from normal human DNA.


Assuntos
DNA de Neoplasias , Leucemia/metabolismo , Doença Aguda , DNA de Neoplasias/metabolismo , Humanos , Cinética , Peso Molecular , Conformação de Ácido Nucleico , Renaturação de Ácido Nucleico
9.
Technol Health Care ; 13(6): 497-510, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16340093

RESUMO

INTRODUCTION: Ultrasound studies evaluating bone tissue generally concentrate on two parameters--velocity and attenuation. This study aimed to determine whether ultrasound signal analysis techniques could provide additional information on the structural and mechanical characteristics of bone. MATERIALS AND METHODS: In vitro measurements were made on 26 left index fingers from human cadavers. Ultrasound measurements at the distal metaphysis and epiphysis; dual-energy X-ray absorptiometry of the whole phalanx; micro-computed tomography at the distal quarter of the phalanx (that is, the distal epiphysis and metaphysis), and mechanical three-point bending tests were performed. Univariate and multivariate linear regression techniques were used to analyze the results. RESULTS: The ultrasound parameters, speed of sound and ultrasound peak amplitude correlated significantly with the three micro-computed tomography measures used to describe the characteristics of mineralized material (r=0.69-0.79, p<0.05). Low frequency ultrasound correlated significantly with micro-computed tomography parameters describing inter-trabecular or marrow spaces (r=0.68-0.78, p<0.05). Comparison of ultrasound parameters with geometric characteristics showed that while speed of sound and ultrasound peak amplitude were related to the cortical area, moment of inertia, and mechanical load (r=0.57-0.83, p< 0.05), the amplitude of the fastest part of the ultrasound signal and full width at 80% maximum of the low frequency peak were related to the relative area of the medullary canal (r=0.40-0.43, p<0.05). DISCUSSION: Quantitative ultrasound may provide information on structural, material and mechanical characteristics of bone to the same extent and even better than DXA Bone Mineral Density. These results have been obtained by a complete and exhaustive use of QUS technology in situ but under clinical conditions. The ultrasound parameters, correctly used and combined, seem to be effective tools for investigating bone tissue.


Assuntos
Falanges dos Dedos da Mão/diagnóstico por imagem , Absorciometria de Fóton , Idoso , Idoso de 80 Anos ou mais , Cadáver , Feminino , Falanges dos Dedos da Mão/anatomia & histologia , Humanos , Masculino , Pessoa de Meia-Idade , Estresse Mecânico , Tomografia Computadorizada por Raios X , Ultrassonografia
10.
Exp Hematol ; 19(3): 196-201, 1991 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-1995311

RESUMO

C3H mice have been used to investigate the effect of a combination of cyclophosphamide (CY) and electromagnetic fields (PEMF). Mice were injected i.p. with a single dose of 200 mg/kg body weight of CY and then exposed to PEMF 24 h per day. In an initial series of experiments immediately after CY injection mice were exposed to PEMF until sacrifice. WBC counts in the peripheral blood demonstrated a quicker decline in WBC at days 1 and 2 in mice exposed to PEMF. Groups of mice were sacrificed at days 1, 4, 6, 8, and 10 after CY injection. In mice exposed to PEMF the spleen weight was less than in controls at days 6, 8, and 10. Autoradiographic studies demonstrated that the labeling index of bone marrow smears did not significantly differ between controls and experimental mice exposed to PEMF, whereas the spleen labeling index proved to be higher among control mice versus mice exposed to PEMF at day 6, and higher among mice exposed to PEMF versus controls at day 8. In a second series of experiments mice were exposed to PEMF only over the 24 h following CY injection. We found that the spleens of mice exposed to PEMF weighed less than those of controls at days 6 and 8. The labeling index of bone marrow did evidence a slight decrease among mice exposed to PEMF at days 8 and 10 after CY injection versus control mice. The spleen labeling index proved to be lower in experimental mice exposed to PEMF than in controls at days 4, 6, and 8. Mice were then injected with CY, half were exposed to PEMF, and 24 h later bone marrow was recovered from both groups of animals. The same number of bone marrow cells was injected via the tail vein into recipient mice irradiated to 8.5 Gy. The grafting efficiency of the bone marrow was evaluated by examining the number of spleen colonies and the spleen and bone marrow labeling indices at day 8; all parameters proved to be significantly lower among mice grafted with the bone marrow of mice injected with CY and exposed to PEMF than among controls injected with CY only. Finally, we found th at the effect of PEMF is evident only if mice are exposed during the 24 h following CY injection. The data reported here indicates that PEMF exposure after CY injection increases the damage induced in mice by CY.


Assuntos
Ciclofosfamida/efeitos adversos , Campos Eletromagnéticos , Animais , Autorradiografia , Contagem de Células Sanguíneas/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Medula Óssea/patologia , Divisão Celular/efeitos da radiação , Ciclofosfamida/administração & dosagem , Ciclofosfamida/uso terapêutico , Injeções Intraperitoneais , Masculino , Camundongos , Camundongos Endogâmicos C3H , Neoplasias Experimentais/tratamento farmacológico , Baço/efeitos dos fármacos , Baço/patologia , Fatores de Tempo
11.
Exp Hematol ; 17(2): 88-95, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-2643520

RESUMO

C3H/Km flora-defined mice were used to investigate the effect of exposure to pulsing electromagnetic field (PEMF) after total body x-ray irradiation. Prolonged exposure to PEMF had no effect on normal nonirradiated mice. When mice irradiated with different doses of x-ray (8.5 Gy, 6.8 Gy, and 6.3 Gy) were exposed to PEMF 24 h a day, we observed a more rapid decline in white blood cells (WBC) in the peripheral blood of mice exposed to PEMF at all the x-ray dosages used. No effect of exposure to PEMF was observed on the survival of the mice irradiated with 6.3 Gy and 8.5 Gy; in mice irradiated with 6.8 Gy, 2 out of 12 survived when exposed to PEMF as compared to 10 out of 12 control mice that were irradiated only. At day 4 after irradiation autoradiographic studies performed on bone marrow and spleen of 8.5-Gy-irradiated mice showed no difference between controls and mice exposed to PEMF, whereas on 6.8-Gy mice the bone marrow labeling index was lower in mice exposed to PEMF. In mice irradiated to 6.3 Gy we observed that the recovery of WBC in the peripheral blood was slowed in mice exposed to PEMF and their body weight was significantly lower than in control mice that were irradiated only. The spleen and bone marrow of the mice irradiated to 6.3 Gy and sacrificed at days 4, 14, 20, and 25 after irradiation were analyzed by autoradiography to evaluate the labeling index. Half of the spleens from mice sacrificed at day 25 after irradiation were used to evaluate the RNA content. Autoradiography showed that in the spleen and bone marrow of control mice, there were more cells labeled with [3H]thymidine at days 4 and 14 and less at days 20 and 25 after irradiation in comparison with mice irradiated and exposed to PEMF. The Northern blot analysis of histone H3 and p53 protein RNAs extracted from the spleens at day 25 after irradiation showed a slight increase in cycling cells among spleens of mice exposed to PEMF. We suggest that the exposure to PEMF immediately after x-ray irradiation results in increased damage.


Assuntos
Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Contagem de Leucócitos/efeitos da radiação , Quimera por Radiação , Animais , Peso Corporal/efeitos da radiação , Medula Óssea/efeitos da radiação , Replicação do DNA/efeitos da radiação , Relação Dose-Resposta à Radiação , Campos Eletromagnéticos/métodos , Fenômenos Eletromagnéticos/métodos , Masculino , Camundongos , Camundongos Endogâmicos C3H , Tamanho do Órgão/efeitos da radiação , Baço/efeitos da radiação , Irradiação Corporal Total
12.
J Bone Miner Res ; 15(12): 2458-66, 2000 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-11127210

RESUMO

Ultrasound (US) waves are mechanical vibrations that are applied to a material--bone tissue--in order to study its properties, that is, density, elasticity, and structure. In this study we evaluated in which way density and elasticity of the spongy bone influenced the transmission of 1.25 MHz US pulses. Twelve cylindrical specimens (diameter, 8 mm; height, 5 mm) excised from phalanxes of pig were decalcified with 0.5 M EDTA for different times (0, 2, and 5 days). During these periods, the samples underwent the following investigations: US transmission, density, and elasticity measurements. To assess the homogeneity of decalcification, the cross-sections of some samples were microradiographed. A detailed analysis of the US signal received was performed using velocity, Fourier analysis, and some parameters typical of signal processing technique. A good correlation was found between US velocity and density (r2 = 0.70); a lower correlation was found between velocity and elasticity (r2 = 0.59). If density and elasticity are considered simultaneously, the correlation with the US velocity improves significantly (r2 = 0.84). Fourier analysis enabled us to observe a shift of the main frequency toward lower values as the decalcification process advanced. We also observed that in the regressions weighted for density, US velocity correlated poorly with elasticity (r2 = 0.16), whereas signal processing parameters maintain a good correlation with elasticity (ultrasound peak amplitude [UPA], r2 = 0.48; slope, r2 = 0.62). In this study, it has been observed that when using a signal processing technique to analyze US pulses, it is possible to identify some parameters that are related in different ways to density and to elastic properties of bone. Our results show the potentiality of US technique to separate information on bone density and elasticity that X-ray-based densitometric methods do not provide.


Assuntos
Densidade Óssea , Osso e Ossos/diagnóstico por imagem , Osso e Ossos/fisiologia , Animais , Técnica de Descalcificação , Elasticidade , Epífises/diagnóstico por imagem , Epífises/fisiologia , Membro Anterior/diagnóstico por imagem , Membro Anterior/fisiologia , Técnicas In Vitro , Processamento de Sinais Assistido por Computador , Suínos , Ultrassonografia
13.
J Bone Miner Res ; 15(8): 1603-14, 2000 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10934660

RESUMO

Phalangeal osteosonogrammetry was introduced as a method for bone tissue investigation in 1992. It is based on the measure of the velocity of ultrasound (amplitude-dependent speed of sound [AD-SoS]) and on the interpretation of the characteristics of the ultrasound signal. In this study we have collected a database of 10,115 subjects to evaluate the performance of AD-SoS and to develop a parameter that is able to quantify the signal characteristics: ultrasound bone profile index (UBPI). The database only includes females of which 4.5% had documented vertebral osteoporotic fractures, 16% lumbar spine dual X-ray absorptiometry (DXA), and 6% hip DXA. The analysis of the ultrasound signal has shown that with aging the UBPI, first wave amplitude (FWA), and signal dynamics (SDy) follow a trend that is different from the one observed for AD-SoS; that is, there is no increase during childhood. In the whole population, the risk of fracture per SD decrease for AD-SOS was odds ratio (OR) 1.71 (CI, 1.58-1.84). The AD-SoS in fractured subjects was significantly lower than in a group of age-matched nonfractured subjects (p < 0.0001). In a small cohort of hip-fractured patients UBPI proved to be lower than in a control age-matched group (p < 0.0001). When the World Health Organization (WHO) working group criteria were applied to this population to identify the T score value for osteoporosis, for AD-SoS we found a T score of -3.2 and for UBPI we found a T score of -3.14. Sixty-six percent of vertebral fractures were below the AD-SoS -3.2 T score and 62% were below UBPI -3.14. We observed the highest incidence of fractures (63.6%) among subjects with AD-SoS who had both DXA T score values below the threshold. We conclude from this study that ultrasound investigation at the hand phalanges is a valid methodology for osteoporosis assessment. It has been possible to quantify signal changes by means of UBPI, a parameter that will improve the possibility of investigating bone structure.


Assuntos
Envelhecimento/fisiologia , Osso e Ossos/diagnóstico por imagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Densitometria , Análise Discriminante , Feminino , Fraturas Ósseas , Humanos , Masculino , Sensibilidade e Especificidade , Ultrassonografia/métodos
14.
FEBS Lett ; 248(1-2): 141-4, 1989 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-2785933

RESUMO

The effects of the exposure of mitogen-stimulated human lymphocytes from aged subjects to low-frequency pulsed electromagnetic fields (PEMFs) were studied by measuring the production of interleukin-2 (IL-2) and the expression of IL-2 receptor. PEMF-exposed cultures that presented increased [3H]thymidine incorporation showed lower amounts of IL-2 in their supernatants, but higher percentages of IL-2 receptor-positive cells and of T-activated lymphocytes. Taken together, these data suggest that PEMFs were able to modulate mitogen-induced lymphocyte proliferation by provoking an increase in utilization of IL-2, most likely acting on the expression of its receptor on the plasma membrane.


Assuntos
Idoso de 80 Anos ou mais , Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Interleucina-2/metabolismo , Linfócitos/metabolismo , Receptores de Interleucina-2/metabolismo , Idoso , Membrana Celular/metabolismo , Feminino , Humanos , Ativação Linfocitária/efeitos dos fármacos , Linfócitos/efeitos dos fármacos , Masculino , Fito-Hemaglutininas/farmacologia
15.
Bone ; 26(3): 297-303, 2000 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-10710005

RESUMO

The capacity of dual x-ray absorptiometry and quantitative ultrasound to discriminate bone loss and to predict the mechanical and microarchitectural properties of cancellous bone in an animal model of osteopenia was evaluated. Thirty-five female Sprague-Dawley rats (10 months old) were randomized into three groups: baseline group, 10 rats killed at the beginning of the study; ovx group, 15 rats ovariectomized; and sham group, 10 rats sham operated. At the beginning and end of the study, all the animals underwent osteosonography to record the proximal tail (C3 vertebra) bone speed of sound. Sixteen weeks after surgery, the animals were euthanized and the L5-6 lumbar vertebrae of each rat were excised for densitometric, biomechanical (compression test), and histomorphometric studies. Significant differences were found among the groups for final speed of sound (p = 0.01). The L5 bone mineral density of the ovx group decreased by 12.1% (p = 0.049) and 12.6% (p = 0.035) compared, respectively, with baseline and sham groups. The biomechanical parameters of the ovx group decreased by 15-47% compared with the other groups, showing significant differences between the ovx and sham groups both for maximal stress (p = 0.026) and elastic modulus (p = 0.013). Histomorphometric parameters of the ovx group showed significant decreases in comparison with other groups. Logistic regression analysis showed that dual X-ray absorptiometry and quantitative ultrasound discriminate ovariectomized and healthy rats with a similar capacity, classifying correctly all rats used in the model in a range of 61-70%. This similar capacity seems to derive from two different capacities to detect bone changes. Dual X-ray absorptiometry, depending on bone mineralization and density, is able to detect modifications in bone stiffness and strength, confirmed also by the correlation with biomechanical data. On the contrary, quantitative ultrasound seems to depend more on cancellous bone microarchitecural changes because it is correlated to histomorphometric parameters.


Assuntos
Osteoporose/diagnóstico por imagem , Ovariectomia/efeitos adversos , Absorciometria de Fóton , Animais , Feminino , Ratos , Ratos Sprague-Dawley , Sensibilidade e Especificidade , Ultrassonografia
16.
Menopause ; 7(6): 402-12, 2000.
Artigo em Inglês | MEDLINE | ID: mdl-11127763

RESUMO

OBJECTIVE: A controlled 4-year follow-up study was conducted on a population composed of 112 healthy early postmenopausal women to evaluate the ability of ultrasound technology in detecting the effects of hormone replacement therapy (HRT) on bone. At the end of the study, 47 untreated and 25 treated women had been evaluated. Cyclic sequential estrogen/progestogen therapy, 50 microg/day of transdermal 17beta-estradiol (Rotta Research Laboratorium) plus 5 mg/day of medrogestone (Wyeth-Ayerst) was used. DESIGN: Ultrasound transmission through the distal metaphysis of hand phalanxes was measured by DBM Sonic. Beside amplitude-dependent speed of sound (AD-SoS), three new parameters could be calculated: pure speed of sound (pSOS), bone transmission time (BTT), and ultrasound bone profile index (UBPI). Ultrasound measurements were taken at baseline and after 1, 2, and 4 years. RESULTS: Among untreated women a significant decrease of all ultrasound parameters was observed at follow-up measurements. In the HRT-treated group we observed a significant increase of AD-SoS, pSoS, and BTT. We qualified as "responders" women in the treated group for whom AD-SoS, pSoS, and BTT increased by more than 2.77 times the coefficient of variation of the measurement, i.e., 95% variability. Women in the treated group were identified as responders at 4 years of follow-up by AD-SoS (56%), pSOS (56%), and BTT (60%). Ultrasound bone profile index declined in both groups, although to a lower extent among HRT-treated subjects. CONCLUSIONS: The 4-year data confirm the results obtained at 1 and 2 years of follow-up. This study demonstrates that bone tissue investigation by ultrasound at the phalanx can be used to monitor the effect of HRT, and thus it should be considered a potential technology for the management of menopause by gynecologists.


Assuntos
Densidade Óssea/efeitos dos fármacos , Estradiol/farmacologia , Dedos/diagnóstico por imagem , Terapia de Reposição Hormonal , Medrogestona/farmacologia , Administração Cutânea , Adulto , Estradiol/administração & dosagem , Feminino , Seguimentos , Humanos , Estudos Longitudinais , Medrogestona/administração & dosagem , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Ultrassonografia
17.
Radiat Res ; 118(1): 161-8, 1989 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-2468172

RESUMO

The effect of exposure to extremely low-frequency pulsed electromagnetic fields (EMFs) on DNA repair capability and on cell survival in human lymphocytes damaged in vitro with gamma rays was studied by two different micromethods. In the first assay, which measures DNA repair synthesis (unscheduled DNA synthesis, UDS), lymphocyte cultures were stimulated with phytohemagglutinin (PHA) for 66 h and then treated with hydroxyurea (which blocks DNA replication), irradiated with 100 Gy of 60Co, pulsed with [3H]thymidine ([3H]TdR), and then exposed to pulsed EMFs for 6 h (the period in which cells repaired DNA damage). In the second assay, which measures cell survival after radiation or chemical damage, lymphocytes were first irradiated with graded doses of gamma rays or treated with diverse antiproliferative agents, and then stimulated with PHA, cultured for 72 h, and pulsed with [3H]TdR for the last 6 h of culture. In this case, immediately after the damage induced by either the radiation or chemicals, cultures were exposed to pulsed EMFs for 72 h, during which cell proliferation took place. Exposure to pulsed EMFs did not affect either UDS or cell survival, suggesting that this type of nonionizing radiation--to which humans may be exposed in the environment, and which is used for both diagnostic and therapeutic purposes--does not affect DNA repair mechanisms.


Assuntos
Reparo do DNA , DNA/efeitos da radiação , Campos Eletromagnéticos/efeitos adversos , Fenômenos Eletromagnéticos/efeitos adversos , Linfócitos/efeitos da radiação , Adolescente , Adulto , Bleomicina/efeitos adversos , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos da radiação , Radioisótopos de Cobalto , Doxorrubicina/efeitos adversos , Raios gama , Humanos , Técnicas In Vitro , Linfócitos/efeitos dos fármacos , Pessoa de Meia-Idade , Vimblastina/efeitos adversos
18.
J Orthop Res ; 8(2): 276-82, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2303961

RESUMO

The effect of an electromagnetic field on the healing of skin ulcers of venous origin in humans has been investigated in a double-blind study. Forty-four patients have been admitted to the study; one-half were exposed to active stimulators (experimental group) and the remaining to dummy stimulators (control group). The stimulation was scheduled to last a maximum of 90 days. The success rate was significantly higher in the experimental group both at day 90 (p less than 0.02) and in the follow-up period (p less than 0.005). The data suggest that the effect of the electromagnetic field lasts even when the stimulation is over. No ulcers worsened in the experimental group, while four worsened in the control group. Twenty-five percent of the patients in the experimental group and 50% in the control group experienced recurrence of the ulcer. It is concluded that stimulation with an electromagnetic field is a useful adjunctive therapy in the management of these patients.


Assuntos
Campos Eletromagnéticos , Fenômenos Eletromagnéticos , Úlcera Cutânea/terapia , Idoso , Método Duplo-Cego , Feminino , Humanos , Masculino , Úlcera Cutânea/etiologia , Úlcera Cutânea/fisiopatologia , Insuficiência Venosa/complicações , Cicatrização/fisiologia
19.
Maturitas ; 27(1): 61-8, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9158079

RESUMO

OBJECTIVES: To evaluate the effectiveness of transdermal oestrogen replacement therapy plus medrogestone (HRT) in postmenopausal bone loss prevention by means of US. METHODS: We enrolled 112 healthy postmenopausal women in an open, prospective study. These women, after a gynaecological evaluation and an US assessment of the skeletal status, were advised to take cyclic sequential oestrogen/progestagen therapy: 50 microg/day of transdermal 17beta-oestradiol (Rotta Research Laboratorium) plus 5 mg/day of medrogestone, for 12 days per cycle (Wyeth-Ayerst). After 1 year we recalled these women: only 32 of them were taking HRT, while 49 had declined HRT without taking alternative therapies. The remaining women were excluded from the study as they were either unavailable for the check-up or they were taking prohibited therapies. We used DBM Sonic 1200 (Igea, Italy) to assess US parameter changes at phalanxes at enrollment and after 1 year. This device enabled us to evaluate US transmission velocity (AD-SoS) and US attenuation pattern (UBPS). In a previous study we had evaluated the intra- and inter-observer reproducibility of AD-SoS measurements (0.4 and 1.0% respectively). Using the same data we evaluated the intra- and inter-observer precision of UBPS. RESULTS: The UBPS intra-operator reproducibilities were 5.3% and 6.1% (for the 1st and the 2nd operator, respectively), while inter-observer precision was 8.8%. Both AD-SoS and UBPS significantly decreased in the non-user group(-0.7%, P < 0.001 and -14.3%, P < 0.001 respectively). In the user group AD-SoS showed a significant increase (+0.7%, P < 0.01), while a slight but significant decrease was observed for UBPS (-2.8%, P < 0.05). CONCLUSIONS: Our findings show that the effectiveness of transdermal HRT in slowing or even arresting postmenopausal bone loss can be monitored by quantitative US studies. The trend difference observed between AD-SoS and UBPS with and without therapy is at least partially explained by a different response to HRT with regard to bone density as well as structure.


Assuntos
Osso e Ossos/efeitos dos fármacos , Osso e Ossos/diagnóstico por imagem , Estradiol/administração & dosagem , Terapia de Reposição de Estrogênios , Medrogestona/administração & dosagem , Osteoporose Pós-Menopausa/prevenção & controle , Congêneres da Progesterona/administração & dosagem , Administração Cutânea , Feminino , Humanos , Osteoporose Pós-Menopausa/diagnóstico por imagem , Estudos Prospectivos , Ultrassonografia
20.
Minerva Ginecol ; 46(7-8): 423-8, 1994.
Artigo em Italiano | MEDLINE | ID: mdl-7970079

RESUMO

The authors assessed the effectiveness and reliability of a new ultrasound system for evaluating the quality of bone tissue in a series of female patients with suspected type I osteoporosis. Evaluation with ultrasound was performed at the distal metaphysis of the first phalanx of the long fingers of the non-dominant hand. The investigation involves the measurement of the AD-SoS and the evaluation of the screen trace of the US signal transmitted through the phalanx. The data supplied by US were compared with the measurement of BMC through DPA on the ultradistal radius performed on the same day. The study involved 94 patients of age 42 to 73 years. A positive correlation was found between AD-SoS and BMC, r = 0.75, and a negative correlation between AD-SoS and the age of the patients, r = -0.62. Ultrasound investigation enables correct identification in 78% of patients; in particular, none of the patients recognized as pathologic at ultrasound investigation figured as normal at DPA. The authors conclude that the system studied is reliable and supplies important information on the quality of bone tissue, and can usefully complement the methods for measuring BMC.


Assuntos
Osso e Ossos/diagnóstico por imagem , Dedos/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Diferencial , Feminino , Humanos , Pessoa de Meia-Idade , Modelos Biológicos , Osteoporose/diagnóstico , Ultrassonografia/instrumentação
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