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1.
Transl Psychiatry ; 6(9): e882, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27598966

RESUMO

Given the strong involvement of affect in obsessive-compulsive disorder (OCD) and recent findings, the current cortico-striato-thalamo-cortical (CSTC) model of pathophysiology has repeatedly been questioned regarding the specific role of regions involved in emotion processing such as limbic areas. Employing a connectomics approach enables us to characterize structural connectivity on a whole-brain level, extending beyond the CSTC circuitry. Whole-brain structural networks of 41 patients and 42 matched healthy controls were analyzed based on 83 × 83 connectivity matrices derived from cortical and subcortical parcellation of structural T1-weighted magnetic resonance scans and deterministic fiber tracking based on diffusion tensor imaging data. To assess group differences in structural connectivity, the framework of network-based statistic (NBS) was applied. Graph theoretical measures were calculated to further assess local and global network characteristics. The NBS analysis revealed a single network consistently displaying decreased structural connectivity in patients comprising orbitofrontal, striatal, insula and temporo-limbic areas. In addition, graph theoretical measures indicated local alterations for amygdala and temporal pole while the overall topology of the network was preserved. To the best of our knowledge, this is the first study combining the NBS with graph theoretical measures in OCD. Along with regions commonly described in the CSTC model of pathophysiology, our results indicate an involvement of mainly temporo-limbic regions typically associated with emotion processing supporting their importance for neurobiological alterations in OCD.


Assuntos
Encéfalo/diagnóstico por imagem , Conectoma , Transtorno Obsessivo-Compulsivo/diagnóstico por imagem , Adulto , Tonsila do Cerebelo/diagnóstico por imagem , Estudos de Casos e Controles , Córtex Cerebral/diagnóstico por imagem , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Processamento de Imagem Assistida por Computador , Lobo Límbico/diagnóstico por imagem , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neostriado/diagnóstico por imagem , Vias Neurais/diagnóstico por imagem , Córtex Pré-Frontal/diagnóstico por imagem , Lobo Temporal/diagnóstico por imagem , Adulto Jovem
2.
Rapid Commun Mass Spectrom ; 30(23): 2537-2544, 2016 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-27619634

RESUMO

RATIONALE: Bulk stable isotope analysis (BSIA) of dissolved matter (e.g. dissolved organic carbon, total nitrogen bound (TNb ), etc.) is of particular importance since this pool is a prime conduit in the cycling of N and C. Studying the two elemental pools is of importance, as transformation and transport processes of N and C are inextricably linked in all biologically mediated systems. No system able to analyze natural abundance stable carbon and nitrogen isotope composition in aqueous samples (without offline sample preparation) and simultaneously has been reported so far. Extension of the high-temperature combustion (HTC) system, to be capable of measuring TNb stable nitrogen isotope composition, is described in this study. METHODS: To extend the TOC analyzer to be capable of measuring TNb , modifications from the HTC high-performance liquid chromatography/isotope ratio mass spectrometry (HPLC/IRMS) interface were implemented and expanded. A reduction reactor for conversion of NOx into N2 was implemented into the new developed system. The extension addresses mainly the development of the focusing unit for nitrogen and a degassing device for online separation of TNb from molecular nitrogen (N2 ) prior to injection. RESULTS: The proof of principle of the system was demonstrated with different compound solutions. In this initial testing, the δ15 NAIR-N2 values of the tested compounds were determined with precision and trueness of typically ≤0.5‰. Good results (u ≤ 0.5‰) could be achieved down to a TNb concentration of 40 mgN/L and acceptable results (u ≤ 1.0‰) down to 5 mgN/L. In addition, the development resulted in the first system reported to be suitable for simultaneous and direct δ13 C and δ15 N BSIA of aqueous samples. CONCLUSIONS: The development resulted in the first system shown to be suitable for both δ13 C and δ15 N direct BSIA in aqueous samples. This system could open up new possibilities in SIA-based research fields. Copyright © 2016 John Wiley & Sons, Ltd.

3.
Neuroimage ; 111: 100-6, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25687594

RESUMO

With the prevalence of obesity rapidly increasing worldwide, understanding the processes leading to excessive eating behavior becomes increasingly important. Considering the widely recognized crucial role of reward processes in food intake, we examined the white matter wiring and integrity of the anatomical reward network in obesity. Anatomical wiring of the reward network was reconstructed derived from diffusion weighted imaging in 31 obese participants and 32 normal-weight participants. Network wiring was compared in terms of the white matter volume as well as in terms of white matter microstructure, revealing lower number of streamlines and lower fiber integrity within the reward network in obese subjects. Specifically, the orbitofrontal cortex and striatum nuclei including accumbens, caudate and putamen showed lower strength and network clustering in the obesity group as compared to healthy controls. Our results provide evidence for obesity-related disruptions of global and local anatomical connectivity of the reward circuitry in regions that are key in the reinforcing mechanisms of eating-behavior processes.


Assuntos
Imagem de Difusão por Ressonância Magnética/métodos , Neostriado/patologia , Rede Nervosa/patologia , Obesidade/patologia , Córtex Pré-Frontal/patologia , Recompensa , Substância Branca/patologia , Adolescente , Adulto , Criança , Feminino , Humanos , Masculino
4.
Food Chem Toxicol ; 56: 223-30, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23462104

RESUMO

Seaweed enriched-restructured pork (RP) is a potential functional food. However, indications of adverse effects associated with herbal medications, which include among others liver failure, toxic hepatitis, and death have been reported. Cholesterol feeding produces hepatomegalia and fat liver infiltration. The effect of seaweed-RP diet, cholesterol-enriched or not, on plasma cholesterol, liver damage markers, structure, and cytochrome CYP4A-1 were evaluated after 5 wk. Eight rat groups were fed a mix of 85% AIN-93M rodent-diet plus 15% RP. The Cholesterol-control (CC), Cholesterol-Wakame (CW), Cholesterol-Nori (CN) and Cholesterol-Sea Spaghetti (CS) groups respectively consumed similar diets to control (C), Wakame (W), Nori (N), and Sea Spaghetti (S) but as part of hypercholesterolaemic diets. CN and CS significantly blocked the hypercholesterolaemic effect observed in CC group. After 5-wk, N and S diets increased the CYP4A-1 expression. However, seaweed-RPs were unable to reduce the histological liver alterations observed in CC group. Larger and more abundant hepatocellular alterations were found in CS and CN rats suggesting that the hypocholesterolaemic effects of these seaweed-RPs seem to be a two-edged sword as they increased liver damage. Future studies are needed to understand the involved mechanisms.


Assuntos
Colesterol na Dieta/administração & dosagem , Fígado Gorduroso/fisiopatologia , Alimento Funcional , Hipercolesterolemia/fisiopatologia , Carne , Alga Marinha/química , Alanina Transaminase/sangue , Fosfatase Alcalina/sangue , Animais , Aspartato Aminotransferases/sangue , Peso Corporal/efeitos dos fármacos , Colesterol na Dieta/efeitos adversos , Colesterol na Dieta/sangue , Sistema Enzimático do Citocromo P-450/metabolismo , Família 4 do Citocromo P450 , Dieta , Fígado Gorduroso/dietoterapia , Hipercolesterolemia/dietoterapia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Fígado/patologia , Tamanho do Órgão/efeitos dos fármacos , Porphyra/química , Ratos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Suínos , Undaria/química
5.
CNS Neurol Disord Drug Targets ; 12(5): 665-79, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23469842

RESUMO

Hipericum perforatum is a well-known herbal for its antidepressant property. Recently, it has been shown to have nootropic effects against neurodegenerative disorders. The aim of the present study was to evaluate the protective role of chronic administration of two standardized extract of Hypericum perforatum SHP1 rich in hyperforin (6%) and SHP2 extract poor in hyperforin (0.2%) on the neurodegeneration induced by chronic administration of rotenone in rats. Quercetin in liposomes, one active constituent, was tested in the same experimental conditions. The animals received pretreatments with SHP1 (4 mg/Kg, ip), SHP2 (4 mg/Kg, ip) or quercetin liposomes (25 and 100 mg/kg, ip) 60 min before of rotenone injection (2.5 mg/kg) for 45 days. Pretreatment of the animals with SHP1 and SHP2 efficiently halted deleterious toxic effects of rotenone, revealing normalization of catalepsy in addition to amelioration of neurochemical parameters. Also, SHP1 reduced neuronal damage, diminishing substantia nigra dopaminergic cell death caused by the pesticide, indicating benefit of neuroprotective therapy. In general, the SHP1 was more active than SHP2. In addition, SHP1 inhibited the apoptotic cascade by decreasing Bax levels. The results presented here indicate that mainly hyperforin and quercetin, may be involved in the neuroprotective action of Hypericum standardized extracts. Combination of dietary antioxidants could provide better therapeutic advantage for the management of Parkinson, and possibly other neurodegenerative disorders. Therefore H. perforatum standardized extract enriched in hyperforin, could be a better alternative for depressed elderly patients with degenerative disorders exhibiting elevated oxidative stress status.


Assuntos
Hypericum/química , Fármacos Neuroprotetores/uso terapêutico , Doença de Parkinson/tratamento farmacológico , Fitoterapia/métodos , Quercetina/uso terapêutico , Análise de Variância , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Encéfalo/diagnóstico por imagem , Encéfalo/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/patologia , Catalepsia/tratamento farmacológico , Corpo Estriado/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/patologia , Modelos Animais de Doenças , Dopamina/metabolismo , Relação Dose-Resposta a Droga , Fluordesoxiglucose F18 , Inseticidas/toxicidade , Lipossomos/uso terapêutico , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Neurônios/patologia , Doença de Parkinson/etiologia , Doença de Parkinson/patologia , Doença de Parkinson/fisiopatologia , Tomografia por Emissão de Pósitrons , Ratos , Ratos Wistar , Rotenona/toxicidade , Natação
6.
Transplant Proc ; 44(6): 1574-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22841218

RESUMO

OBJECTIVE: Using a percutaneous ecoguided injection system to obtain chimeric piglets through a less invasive and traumatic technique than previously reported. MATERIALS AND METHODS: The two types of human cells included umbilical cord blood mononuclear elements and mesenchymal stem cells cultured from bone marrow. Four sows at gestational day 50 were anesthetized. A needle was inserted through the skin and uterine wall to reach the peritoneal cavity of the fetuses under continuous ultrasound guidance. Fourteen piglets were injected with various cell concentrations. RESULTS: All sows carried pregnancies to term yielding 69 piglets, among which 67 were alive and two mummified. Two piglets died during the first 48 hours of life. Chimerism was detected using flow cytometry and by quantitative polymerase chain reaction (q-PCR) to detect Alu gene in blood or tissues samples. The analysis detected blood chimerism in 13 piglets (21%) by flow cytometry and the presence of the human Alu gene in 33 (51%) by q-PCR. The results suggest cell trafficking between littermates after in utero injection. CONCLUSIONS: Transcutaneous echo-guided injection succeeded to produce chimeric piglets without disadvantages to the sow or the fetuses and avoiding abortions or fetal death.


Assuntos
Transplante de Medula Óssea/imunologia , Transplante de Células-Tronco de Sangue do Cordão Umbilical/efeitos adversos , Transplante de Células-Tronco Mesenquimais/efeitos adversos , Quimeras de Transplante , Tolerância ao Transplante , Elementos Alu , Animais , Animais Recém-Nascidos , Células Cultivadas , Feminino , Citometria de Fluxo , Idade Gestacional , Cobaias , Humanos , Injeções , Gravidez , Reação em Cadeia da Polimerase em Tempo Real , Suínos , Transplante Heterólogo , Ultrassonografia de Intervenção
7.
Eur Radiol ; 22(11): 2525-32, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22648049

RESUMO

OBJECTIVE: To investigate the utility of acoustic radiation force impulse (ARFI) imaging, with the determination of shear wave velocity (SWV), to differentiate non-alcoholic fatty liver disease (NAFLD) from non-alcoholic steatohepatitis (NASH) in patients with morbid obesity before bariatric surgery. METHODS: Thirty-two patients with morbid obesity were evaluated with ARFI and conventional ultrasound before bariatric surgery. The ARFI and ultrasound results were compared with liver biopsy findings, which is the reference standard. The patients were classed according to their histological findings into three groups: group A, simple steatosis; group B, inflammation; and group C, fibrosis. RESULTS: The median SWV was 1.57 ± 0.79 m/s. Hepatic alterations were observed in the histopathological findings for all the patients in the study (100 %), with the results of the laboratory tests proving normal. Differences in SWV were also observed between groups A, B and C: 1.34 ± 0.90 m/s, 1.55 ± 0.79 m/s and 1.86 ± 0.75 m/s (P < 0.001), respectively. The Az for differentiating NAFLD from NASH or fibrosis was 0.899 (optimal cut-off value 1.3 m/s; sensitivity 85 %; specificity 83.3 %). CONCLUSION: The ARFI technique is a useful diagnostic tool for differentiating NAFLD from NASH in asymptomatic patients with morbid obesity. KEY POINTS : • Acoustic radiation force impulse imaging provides ultrasonic shear wave velocity measurements. • SWV measurements were higher in patients with inflammation or fibrosis than NAFLD. • ARFI differentiates NAFLD from NASH in patients with morbid obesity. • Results suggest that ARFI can detect NASH in asymptomatic morbidly obese patients.


Assuntos
Cirurgia Bariátrica/métodos , Fígado Gorduroso/complicações , Fígado Gorduroso/diagnóstico , Obesidade Mórbida/complicações , Ultrassonografia/métodos , Acústica , Adulto , Biópsia , Feminino , Humanos , Inflamação , Fígado/diagnóstico por imagem , Fígado/fisiopatologia , Masculino , Pessoa de Meia-Idade , Hepatopatia Gordurosa não Alcoólica , Estudos Prospectivos , Curva ROC , Padrões de Referência , Reprodutibilidade dos Testes , Resistência ao Cisalhamento , Estresse Mecânico
8.
Methods Enzymol ; 509: 87-99, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22568902

RESUMO

With the rapidly advancing field of nanotechnology having an impact in several areas interfacing life and physical sciences, the potential applications of nanoparticles as antimicrobial agents have been realized and offer great opportunities in addressing several viral and bacterial outbreak issues. Polyurethanes (PUs) are a diverse class of polymeric materials which also have applications in several areas of biomedical science ranging from blood contact devices to implantable dental technologies. In this report, copper oxide (CuO) nanoparticles (mean size ∼50 nm) are embedded into a PU matrix via two electrical fabrication processes. To elucidate the antimicrobial activity, a range of different loading compositions of CuO within the PU matrix (0%, 1%, 5%, and 10% w/w) are electrospun to form thin porous films (thickness < 10 µm). After washing, the films are tested for their antimicrobial properties against methicillin-resistant Staphylococcus aureus (MRSA). Significant reduction of populations was demonstrated with 10% w/w CuO over a 4-h period. This approach demonstrates the potential of generating tailored antimicrobial structures for a host of applications, such as designer filters, patterned coatings, breathable fabrics, adhesive films (as opposed to sutures), and mechanically supporting structures.


Assuntos
Cobre/farmacologia , Elastômeros/farmacologia , Nanocompostos/química , Poliuretanos/química , Antibacterianos/química , Antibacterianos/farmacologia , Cobre/química , Elastômeros/química , Membranas Artificiais , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Viabilidade Microbiana/efeitos dos fármacos , Nanocompostos/ultraestrutura , Tamanho da Partícula , Porosidade , Propriedades de Superfície
9.
Eur J Pain ; 16(1): 61-71, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21684787

RESUMO

Neuropathic pain is often accompanied by stress, anxiety and depression. Although there is evidence for involvement of corticotropin-releasing factor (CRF), the detailed neuronal basis of these pain-related mood alterations is unknown. This study shows that peripheral mononeuropathy was accompanied by changes in limbic forebrain CRF, but did not lead to changes in the functioning of the hypothalamo-pituitary-adrenal axis and the midbrain Edinger-Westphal centrally projecting (EWcp) neuron population, which play main roles in the organism's response to acute pain. Twenty-four days after chronic constriction injury (CCI) of the rat sciatic nerve, the oval bed nucleus of the stria terminalis (BSTov) contained substantially more Crf mRNA as did the central amygdala (CeA), which, in addition, possessed more CRF. In contrast, Crf mRNA and CRF contents of the hypothalamic paraventricular nucleus (PVN) were unaffected by CCI. Similarly, EWcp neurons, producing the CRF family member urocortin 1 (Ucn1) and constitutively activated by various stressors including acute pain, did not show an effect of CCI on Ucn1 mRNA or Ucn1. Also, the immediate early gene products cFos and deltaFosB in the EWcp were unaffected by CCI. These results indicate that neuropathic pain does not act via the HPA-axis or the EWcp, but includes a main role of Crf in the limbic system, which is in clear contrast to stressors like acute and chronic pain, which primarily act on the PVN and the EWcp.


Assuntos
Hormônio Liberador da Corticotropina/metabolismo , Sistema Límbico/metabolismo , Neuralgia/metabolismo , Tonsila do Cerebelo/metabolismo , Tonsila do Cerebelo/patologia , Animais , Peso Corporal/fisiologia , Constrição Patológica/metabolismo , Constrição Patológica/patologia , Hiperalgesia/metabolismo , Processamento de Imagem Assistida por Computador , Imuno-Histoquímica , Hibridização In Situ , Sistema Límbico/patologia , Masculino , Neuralgia/patologia , Medição da Dor , Proteínas Proto-Oncogênicas c-fos/biossíntese , Proteínas Proto-Oncogênicas c-fos/genética , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Ratos , Ratos Sprague-Dawley , Neuropatia Ciática/metabolismo , Neuropatia Ciática/patologia , Núcleos Septais/metabolismo , Núcleos Septais/patologia , Fixação de Tecidos , Urocortinas/biossíntese , Urocortinas/genética , Aumento de Peso/fisiologia
10.
J Nutr Health Aging ; 15(10): 852-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22159772

RESUMO

OBJECTIVE: To assess the prevalence of the frailty syndrome and its associated variables among the older adult population in the province of Toledo (Spain). METHODS: Data were taken from the Toledo Study for Healthy Aging, a population-based study conducted on 2,488 individuals aged 65 years and older. Study participants were selected by a two-stage random sampling from the municipal census of Toledo, covering both institutionalized and community dwelling persons from rural and urban settings. Data were collected from 2006 to 2009, and included information on social support, activities of daily living, comorbidity, physical activity, quality of life, depressive symptoms, and cognitive function. In addition, a nurse collected anthropometric data, conducted tests of physical performance (walk speed, upper and lower extremities strength, and the stand-and-sit from a chair test) and obtained a blood sample. The diagnosis of the frailty syndrome was based on the Fried criteria (weakness, low speed, low physical activity, exhaustion, and weight loss). RESULTS: In total, 41.8% (95% confidence interval [CI] 39.4-44.2%) of the study participants were prefrail, and 8.4% (95% CI 7.1-9.8%) were frail. There were no differences in the prevalence of frailty by sex, level of education, occupation, marital status, or place of residence. The frequency of the frailty syndrome increased with age, and was higher in those with disability, depression, hip fracture and other comorbidity, such as cardiovascular disease and disorders of the central nervous system. CONCLUSIONS: The prevalence of the frailty syndrome in older Spanish adults is high and similar to that reported in other populations in the Mediterranean basin.


Assuntos
Atividades Cotidianas , Fadiga/epidemiologia , Idoso Fragilizado , Avaliação Geriátrica , Força Muscular , Debilidade Muscular/epidemiologia , Aptidão Física , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Comorbidade , Pessoas com Deficiência , Exercício Físico , Feminino , Marcha , Humanos , Masculino , Atividade Motora , Prevalência , Espanha/epidemiologia , Síndrome , Redução de Peso
11.
J Mater Sci Mater Med ; 22(3): 491-6, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21243517

RESUMO

Nano-sized titanium containing hydroxyaptite has been prepared, the particle size of nanoTiHA was shown to be 12-20 nm in width and 30-40 nm in length, smaller than that of nanoHA. X-ray diffraction analysis revealed the phase purity of nanoTiHA produced. Antimicrobical assays demonstrated that nanoTiHA has excellent growth inhibitory properties, and is able to inhibit the growth of all bacterial strains tested, both Gram-negative and Gram-positive species, including multi-antibiotic resistant EMRSA 15 and EMRSA 16 'superbugs'. Biocidal activity against all four Staphylococcus spp was also shown at the concentration tested. Nanostuctured TiHA coating was successfully deposited onto Ti surfaces using EHDA spraying under optimized processing conditions with the thickness of the coating being further controlled by the spraying time. All of the nanoTiHA coated Ti surfaces were able to support human osteoblast (HOB) cell attachment and growth. The coating thickness did not significantly influence the proliferation of HOB cells on nanoTiHA coatings, while the ability of nanoTiHA coating to support HOB cell differentiation was demonstrated from the alkaline phosphatase activity. Our study showed that nanoTiHA has excellent anti-bacterial properties and the thin nanoTiHA coating was also able to support the attachment, growth and differentiation of HOB cells. Therefore, nanoTiHA coating could pave the way for the development of the next generation of dental and orthopedic implants by offering anti-infection potential in addition to osteoconductivity.


Assuntos
Durapatita/química , Nanopartículas Metálicas/química , Nanotecnologia/métodos , Titânio/química , Fosfatase Alcalina/metabolismo , Antibacterianos/química , Materiais Biocompatíveis/química , Materiais Biomédicos e Odontológicos , Adesão Celular , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Proliferação de Células , Materiais Revestidos Biocompatíveis/farmacologia , Compostos de Diazônio/química , Farneseno Álcool/análogos & derivados , Farneseno Álcool/química , Humanos , Hidrodinâmica , Microscopia Eletrônica de Transmissão/métodos , Osteoblastos/metabolismo , Próteses e Implantes , Staphylococcus/metabolismo , Difração de Raios X
12.
Radiologia ; 51(3): 282-6, 2009.
Artigo em Espanhol | MEDLINE | ID: mdl-19409583

RESUMO

OBJECTIVE: The aim of this study was to determine whether using a film with radiopaque coordinates placed over the region of interest to guide shoulder arthrography can reduce the dose of radiation received by patients. MATERIAL AND METHODS: The entrance dose was obtained in 34 patients (mean age, 44 years; range, 15 to 75 years). The dose received by organs at risk and the effective dose were estimated with Monte Carlo techniques using the following input parameters: patient anatomy, examination geometry, and air kerma at the entrance to the patient without backscattering. Arthrography was performed with a remote controlled device and images were acquired digitally without fluoroscopy. RESULTS: The mean thickness of the shoulders studied was 14.6+/-2.1cm (9-20 cm). Images were obtained with 80+/-10 kVp (60-85 kVp) and 6.5+/-3.5 mAs (1.4-17 mAs). The mean time of irradiation for each patient was 20+/-6 ms (6.9-47.9 ms). The calculated air kerma was 0.41+/-0.19 mGy and the effective dose was 0.79+/-0.40 muSv. CONCLUSIONS: The technique described in this study has enabled us to reduce the dose of radiation received by patients undergoing shoulder arthrography in comparison with other techniques described in the literature and to ensure that the radiologist performing the procedure is not irradiated.


Assuntos
Artrografia/métodos , Doses de Radiação , Articulação do Ombro/diagnóstico por imagem , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
13.
Radiología (Madr., Ed. impr.) ; 51(3): 282-286, mayo 2009. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-72895

RESUMO

Objetivo: El objetivo de este estudio fue reducir la dosis de radiación recibida por los pacientes sometidos a una artrografía de hombro y en los que se utiliza como sistema de guiado una placa con coordenadas radiopacas situada sobre el área de interés. Material y métodos: La dosis a la entrada se obtuvo en 34 pacientes con edades comprendidas entre 15 y 75 años, media de 44 años. La dosis a órganos de riesgo y la dosis efectiva se estimaron mediante técnicas de Monte Carlo, donde los parámetros de entrada son: anatomía del paciente, geometría de la exploración y kerma en aire a la entrada del paciente sin retrodispersión. Las artrografías se realizaron en un equipo telemando y las imágenes se obtuvieron mediante adquisición digital sin fluoroscopia. Resultados: El espesor medio de los hombros estudiados fue 14,6±2,1 cm (9-20 cm). Las imágenes se obtuvieron con 80±10kVp (60-85kVp) y 6,5±3,5 mAs (1,4-17 mAs). El tiempo medio de irradiación para cada paciente fue 20 ± 6ms (6,9-47,9ms). El kerma en aire calculado fue de 0,41 ± 0,19 mGy y la dosis efectiva de 0,79 ± 0,40 μ Sv. Conclusiones: La técnica descrita en este trabajo ha permitido reducir la dosis de radiación al paciente respecto a otros procedimientos descritos en la bibliografía y que el radiólogo que realiza la artrografía no se irradie durante el procedimiento (AU)


Objective: The aim of this study was to determine whether using a film with radiopaque coordinates placed over the region of interest to guide shoulder arthrography can reduce the dose of radiation received by patients. Material and methods: The entrance dose was obtained in 34 patients (mean age, 44 years; range, 15 to 75 years). The dose received by organs at risk and the effective dose were estimated with Monte Carlo techniques using the following input parameters: patient anatomy, examination geometry, and air kerma at the entrance to the patient without backscattering. Arthrography was performed with a remote controlled device and images were acquired digitally without fluoroscopy. Results: The mean thickness of the shoulders studied was 14.6±2.1cm (9–20cm). Images were obtained with 80±10kVp (60–85kVp) and 6.5±3.5mAs (1.4–17mAs). The mean time of irradiation for each patient was 20±6ms (6.9–47.9ms). The calculated air kerma was 0.41±0.19mGy and the effective dose was 0.79±0.40 μSv. Conclusions: The technique described in this study has enabled us to reduce the dose of radiation received by patients undergoing shoulder arthrography in comparison with other techniques described in the literature and to ensure that the radiologist performing the procedure is not irradiated (AU)


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Artrografia/instrumentação , Artrografia , Ombro/patologia , Ombro , Radiometria/métodos , Artrografia/estatística & dados numéricos , Artrografia/tendências , Fluoroscopia
14.
Photosynth Res ; 99(1): 1-10, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18819016

RESUMO

The influence of the protein environment on the primary electron donor, P, a bacteriochlorophyll a dimer, of reaction centers from Rhodobacter sphaeroides, has been investigated using electron paramagnetic resonance and electron nuclear double resonance spectroscopy. These techniques were used to probe the effects on P that are due to alteration of three amino acid residues, His L168, Asn L170, and Asn M199. The introduction of Glu at L168, Asp at L170, or Asp at M199 changes the oxidation/reduction midpoint potential of P in a pH-dependent manner (Williams et al. (2001) Biochemistry 40, 15403-15407). For the double mutant His L168 to Glu and Asn at L170 to Asp, excitation results in electron transfer along the A-side branch of cofactors at pH 7.2, but at pH 9.5, a long-lived state involving B-side cofactors is produced (Haffa et al. (2004) J Phys Chem B 108, 4-7). Using electron paramagnetic resonance spectroscopy, the mutants with alterations of each of the three individual residues and a double mutant, with changes at L168 and L170, were found to have increased linewidths of 10.1-11.0 G compared to the linewidth of 9.6 G for wild type. The Special TRIPLE spectra were pH dependent, and at pH 8, the introduction of aspartate at L170 increased the spin density ratio, rho (L)/rho (M), to 6.1 while an aspartate at the symmetry related position, M199, decreased the ratio to 0.7 compared to the value of 2.1 for wild type. These results indicate that the energy of the two halves of P changes by about 100 meV due to the mutations and are consistent with the interpretation that electrostatic interactions involving these amino acid residues contribute to the switch in pathway of electron transfer.


Assuntos
Bacterioclorofila A/metabolismo , Complexo de Proteínas do Centro de Reação Fotossintética/metabolismo , Rhodobacter sphaeroides/metabolismo , Coenzimas/metabolismo , Espectroscopia de Ressonância de Spin Eletrônica , Mutação/genética , Fotossíntese
17.
Food Chem Toxicol ; 46(3): 1111-8, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18096288

RESUMO

Aluminum (Al)-induced neurotoxicity is well known and different salts of aluminum have been reported to accelerate oxidative damage to biomolecules. The present study has examined whether silicon consumed in the form of silicic acid or beer could potentially inhibit aluminum toxicity in the brain. Male mice were administered with Al(NO(3))(3) orally at a dose of 450 mg/kg/day in drinking water for 3 month. Experimental mice were given Al(NO(3))(3) along with 50 mg/L of silicic acid or with 0.5 ml/day of beer. Al brain levels in the Al group were four times higher than those of control mice while silicic acid and beer group values were 40% lower than those of the Al group. We have observed that beer prevented accumulation of lipid damage significantly, which resulted from aluminum intake. Decline in the expression of mRNA of endogenous antioxidant enzymes associated with aluminum administration was also inhibited by beer and silicic acid. The tumor necrosis factor alpha (TNFalpha) RNA expression was normalized in silicic acid and beer groups. Very high and significant correlations were found for the different parameters tested suggesting that moderate consumption of beer, due to its silicon content, effectively protects against the neurotoxic effects of aluminum.


Assuntos
Alumínio/toxicidade , Cerveja , Encéfalo/efeitos dos fármacos , Enzimas/genética , Expressão Gênica/efeitos dos fármacos , Fator de Necrose Tumoral alfa/genética , Animais , Sequência de Bases , Encéfalo/metabolismo , Primers do DNA , Masculino , Camundongos , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
18.
Acta Radiol ; 48(1): 96-103, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17325933

RESUMO

PURPOSE: To evaluate the diagnostic accuracy of arthrography, magnetic resonance (MR) imaging, and MR arthrography in the detection and localization of defects of the triangular fibrocartilage (TFC) in cadaveric wrists, using arthroscopy as a reference standard. MATERIAL AND METHODS: Twenty-four specimen wrists were evaluated. The different imaging modalities were blinded to reviewers and were interpreted independently. A classification of TFC defects was used for the evaluation of images in the different imaging modalities, thus permitting a more uniform correlation. Two cases were excluded from the MR imaging study because of poor image quality. Contingency tables with the chi-square test and Fisher's exact test were used for statistical analysis. RESULTS: Defects of the TFC were identified in 17 of the 24 specimen wrists by means of arthroscopy, and 16 defects were observed when arthrography was carried out. With MR imaging 14 defects of the TFC were detected in the 22 specimen wrists evaluated, and with MR arthrography 16 defects were observed. Most defects were central or combined (two or more defects). In comparison to arthroscopy, the accepted diagnostic gold standard, the following results were found for arthrography in the detection of TFC defects: sensitivity 95%, specificity 100%, and accuracy 95% (P<0.0005); for MR imaging: sensitivity 86%, specificity 85%, and accuracy 70% (P<0.002); and for MR arthrography: sensitivity 100%, specificity 85%, and accuracy 95% (P<0.0005). CONCLUSION: The results of the study seem to indicate that both arthrography and MR arthrography have high accuracy, and either would be useful for evaluation of the TFC. The combined approach using both techniques would have a very high accuracy equivalent to that resulting from arthroscopy.


Assuntos
Artrografia/métodos , Imageamento por Ressonância Magnética/métodos , Fibrocartilagem Triangular/diagnóstico por imagem , Fibrocartilagem Triangular/patologia , Punho/diagnóstico por imagem , Punho/patologia , Cadáver , Meios de Contraste/administração & dosagem , Humanos , Variações Dependentes do Observador , Padrões de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
19.
Neuropharmacology ; 52(2): 606-16, 2007 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-17070561

RESUMO

Since oxidative stress is implicated in the pathophysiology of dementia and depression, this study was designed to investigate the pro-oxidant activity of rotenone, the protective role of standardized extract of Hypericum perforatum (SHP), as well as the mRNA levels of antioxidant enzymes, in brain homogenates of rats following exposure to rotenone and SHP extract. Quercetin in liposomes, one active constituent, was tested in the same experimental conditions to serve as a positive control. The animals received pretreatment with SHP (4 mg/kg) or quercetin liposomes (25 and 100 mg/kg) 60 min before of rotenone injection (2 mg/kg). All treatments were given intraperitoneally in a volume of 0.5 ml/kg body weight, for 45 days. Rotenone treatment increased activities of superoxide dismutase (SOD), glutathione peroxidase (GPx) and levels of malondialdehyde (MDA). The content of reduced glutathione (GSH) was decreased due to chronic rotenone treatment. Rotenone significantly induced the gene expression of CuZnSOD, MnSOD; CAT and GPx in brain. In contrast, SHP extract exerted an antioxidant action which was related with a decreased of MnSOD activity and mRNA levels of some antioxidant enzymes evaluated. Liposomal quercetin treatment resulted in a significant preservation of the activities of antioxidant enzymes and a decreased in the mRNA levels of these antioxidant enzymes. One possible mechanism of action of SHP extract may be related to quercetin in protecting neurons from oxidative damage. Therefore standardized extract of H. perforatum could be a better alternative for depressed elderly patients with degenerative disorder exhibiting elevated oxidative stress status.


Assuntos
Antioxidantes/farmacologia , Regulação da Expressão Gênica/efeitos dos fármacos , Hypericum/química , Estresse Oxidativo/efeitos dos fármacos , Rotenona/farmacologia , Desacopladores/farmacologia , Análise de Variância , Animais , Peso Corporal/efeitos dos fármacos , Interações Medicamentosas , Glutationa Peroxidase/genética , Glutationa Peroxidase/metabolismo , Lipossomos/metabolismo , Malondialdeído/metabolismo , Quercetina/farmacologia , RNA Mensageiro/biossíntese , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Fatores de Tempo
20.
Acta Radiol ; 47(7): 725-9, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16950712

RESUMO

PURPOSE: To present a systematic approach to teaching a technique for arthrography of the shoulder. Using an adhesive marker-plate with radiopaque coordinates, precise sites for puncture can be identified and the need for fluoroscopic guidance obviated. MATERIAL AND METHODS: Forty-six glenohumeral arthrograms were performed in 45 patients; in 1 case involving examination of both shoulders. The stages of the technique are described in detail, as are the fundamental aspects of achieving an effective glenohumeral injection. Pain intensity was measured in all patients using a verbal description scale. RESULTS: Shoulder arthrography was successful in all cases. Average time taken for the procedure was 7 min, with no difference in the respective times required by an experienced radiologist and a resident. The procedure was well tolerated by most patients, with slight discomfort being observed in a very few cases. CONCLUSION: The arthrographic technique used in this study is simple, safe, rapid, and reproducible, and has the advantage of precise localization of the site for puncture without need for fluoroscopic guidance. The procedure described in this study can be of help in teaching residents and can reduce the learning curve for radiologists with no experience in arthrographic methods. It also reduces the time of exposure to fluoroscopy.


Assuntos
Artrografia/métodos , Articulação do Ombro/diagnóstico por imagem , Adulto , Idoso , Meios de Contraste/administração & dosagem , Feminino , Gadolínio DTPA/administração & dosagem , Humanos , Iohexol/administração & dosagem , Iohexol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Medição da Dor , Punções
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