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1.
Plant Foods Hum Nutr ; 76(3): 297-303, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34218401

RESUMO

Time-restricted feeding and food enriched in polyphenols are strategies to prevent or reduce metabolic disorders. Bean leaves (Phaseolus vulgaris L.) are a recognized source of polyphenolic compounds, whose effects on metabolic pathways are not well studied. We evaluated the combined effects of dietary supplementation with Phaseolus vulgaris leaves (10% w/w) (BL) and a 7-h daytime-restricted feeding protocol (RF) under a hypercaloric diet (high fat + high fructose) (HFFD) on the metabolic parameters related to glucose and lipid handling. Adult male Wistar rats were treated for 8 weeks with standard and HFFD diets with or without BL. The results showed that RF improved metabolic alterations induced by HFFD (e.g., hepatic steatosis, increased triacylglycerols, and serum lipoproteins). Supplementation with BL significantly enhanced this effect and downregulated the mRNA expression of carbohydrate and lipid metabolism genes in the liver. These results indicate that dietary supplementation with BL enhances the benefits elicited by RF.


Assuntos
Frutose , Phaseolus , Animais , Dieta Hiperlipídica/efeitos adversos , Suplementos Nutricionais , Fígado , Folhas de Planta , Ratos , Ratos Wistar
2.
Environ Res ; 179(Pt A): 108784, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31606614

RESUMO

BACKGROUND AND OBJECTIVES: Despite the biological plausibility of the association between heavy metal exposure and mental health disorders, epidemiological evidence remains scarce. The objective was to estimate the association between heavy metals and metalloids in soil and the prevalence of mental disorders in the adult population of Spain. METHODS: Individual data came from the Spanish National Health Survey 2011-2012, 18,073 individuals residing in 1772 census sections. Mental health was measured with the 12-item General Health Questionnaire. The concentration estimates of heavy metal and metalloid levels in topsoil (upper soil horizon) came from the Geochemical Atlas of Spain based on 13,317 soil samples. Levels of lead (Pb), arsenic (As), cadmium (Cd) and manganese (Mn) were estimated in each census section by "ordinary Kriging". Odds ratios (OR) were calculated by multilevel logistic regression models. RESULTS: Compared with the lowest Pb concentration levels quartile, the OR for the second quartile was 1.29 (95%CI: 1.11-1.50), increasing progressively to 1.37 (95%CI: 1.17-1.60) and 1.51 (95%CI: 1.27-1.79) in the third and fourth quartiles, respectively. For As, the association was observed in the third and fourth quartiles: 1.21 (95%CI: 1.04-1.41) and 1.42 (95% CI: 1.21-1.65), respectively. Cd was associated also following a gradient from the second quartile: 1.34 (95%CI: 1.15-1.57) through the fourth: 1.84 (95%CI: 1.56-2.15). In contrast, Mn only showed a positive association at the second quartile. Additionally, individuals consuming vegetables > once a day the OR for the fourth quartile of Pb concentration, vs. the first, increased to 2.93 (95%CI: 1.97-4.36); similarly for As: 3.00 (95%CI: 2.08-4.31), and for Cd: 3.49 (95%CI: 2.33-5.22). CONCLUSIONS: Living in areas with a higher concentration of heavy metals and metalloids in soil was associated with an increased probability of having a mental disorder. These relationships were strengthened in individuals reporting consuming vegetables > once a day.


Assuntos
Exposição Ambiental/estatística & dados numéricos , Transtornos Mentais/epidemiologia , Saúde Mental/estatística & dados numéricos , Metais Pesados , Poluentes do Solo , Adulto , Cádmio , Monitoramento Ambiental , Humanos , Metaloides , Espanha/epidemiologia
3.
BMC Pediatr ; 16(1): 213, 2016 12 13.
Artigo em Inglês | MEDLINE | ID: mdl-27964729

RESUMO

BACKGROUND: To create a self-reported, internet-based questionnaire for the assessment of suicide risk in children and adolescents. METHODS: As part of the EU project 'Suicidality: Treatment Occurring in Paediatrics' (STOP project), we developed web-based Patient Reported Outcome Measures (PROMs) for children and adolescents and for proxy reports by parents and clinicians in order to assess suicidality. Based on a literature review, expert panels and focus groups of patients, we developed the items of the STOP Suicidality Assessment Scale (STOP-SAS) in Spanish and English, translated it into four more languages, and optimized it for web-based presentation using the HealthTrackerTM platform. Of the total 19 questions developed for the STOP-SAS, four questions that assess low-level suicidality were identified as screening questions (three of them for use with children, and all four for use with adolescents, parents and clinicians). A total of 395 adolescents, 110 children, 637 parents and 716 clinicians completed the questionnaire using the HealthTrackerTM, allowing us to evaluate the internal consistency and convergent validity of the STOP-SAS with the clinician-rated Columbia Suicide Severity Rating Scale (C-SSRS). Validity was also assessed with the receiver operating characteristic (ROC) area of the STOP-SAS with the C-SSRS. RESULTS: The STOP-SAS comprises 19 items in its adolescent, parent, and clinician versions, and 14 items in its children's version. Good internal consistency was found for adolescents (Cronbach's alpha: 0.965), children (Cronbach's alpha: 0.922), parents (Cronbach's alpha: 0.951) and clinicians (Cronbach's alpha: 0.955) versions. A strong correlation was found between the STOP-SAS and the C-SSRS for adolescents (r:0.670), parents (r:0.548), clinicians (r:0.863) and children (r:0.654). The ROC area was good for clinicians' (0.917), adolescents' (0.834) and parents' (0.756) versions but only fair (0.683) for children's version. CONCLUSIONS: The STOP-SAS is a comprehensive, web-based PROM developed on the HealthTrackerTM platform, and co-designed for use by adolescents, children, parents and clinicians. It allows the evaluation of aspects of suicidality and shows good reliability and validity.


Assuntos
Escalas de Graduação Psiquiátrica , Prevenção do Suicídio , Adolescente , Criança , Feminino , Grupos Focais , Humanos , Internet , Masculino , Medidas de Resultados Relatados pelo Paciente , Pediatria , Psicometria , Curva ROC , Reprodutibilidade dos Testes , Medição de Risco , Autorrelato , Suicídio/psicologia
4.
Rev Gastroenterol Mex ; 81(1): 11-20, 2016.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-26811038

RESUMO

BACKGROUND: Helicobacter pylori (H. pylori) is associated with gastroduodenal diseases. Virulence of clinical isolates is related to clinical outcome. Moreover, with microdiversity studies in clinical isolates from a single patient, but from a different origin (antrum or corpus), it is possible to demonstrate that there are simultaneous mixed infections. AIMS: To genotype H. pylori strains with multiplex PCR, according to their clinical virulence, and in this manner know the frequency of each genotype and relate it to clinical outcome in order to prevent the development of severe diseases. METHODS: A total of 210 patients with gastric alterations were studied. Virulence classification of H. pylori strains was carried out with multiplex PCR and 127 strains were identified as H. pylori by PCR (glmM and cagE). Genotype and clinical outcome were evaluated with the Fisher's exact test. In addition, RAPD-PCR was performed as a fingerprinting method to analyze mixed infections. RESULTS: The cagA, vacAs1, and vacAm1 genes were detected in all the clinical isolates. Strains were classified as: type i, 40.15% (51/127); type ii, 22.04% (28/127); and type iii, 28.4% (36/127), but two new different genotypes were also detected: (1) babA2+, cagA+, vacAs1+, 6.29% (8/127) and (2) babA2+, cagA-, vacAs2/m2+, 3.14% (4/127). The cagE gene was detected in type i strains. CONCLUSIONS: The Fisher's exact test did not support a significant association between clinical outcome and genotype. The main circulating genotypes in the Mexican population studied were: cagA+, vacAs1, and vacAm1. Multiplex PCR can be used as a screening test for H. pylori strains. Furthermore, the cagE gene is a good marker for identifying cag-PAI positive strains.


Assuntos
Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/microbiologia , Helicobacter pylori/genética , Fatores de Virulência/genética , Adolescente , Criança , Pré-Escolar , DNA Bacteriano/genética , Feminino , Genótipo , Humanos , Masculino , México/epidemiologia , Pessoa de Meia-Idade , Resultado do Tratamento
5.
Pharmacogenomics J ; 15(3): 288-92, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25348618

RESUMO

Cytochrome P450 3A4 (CYP3A4) is a key drug-metabolizing enzyme. Loss-of-function variants have been reported as rare events, and the first demonstration of a CYP3A4 protein lacking functional activity is caused by CYP3A4*20 allele. Here we characterized the world distribution and origin of CYP3A4*20 mutation. CYP3A4*20 was determined in more than 4000 individuals representing different populations, and haplotype analysis was performed using CYP3A polymorphisms and microsatellite markers. CYP3A4*20 allele was present in 1.2% of the Spanish population (up to 3.8% in specific regions), and all CYP3A4*20 carriers had a common haplotype. This is compatible with a Spanish founder effect and classifies CYP3A4 as a polymorphic enzyme. This constitutes the first description of a CYP3A4 loss-of-function variant with high frequency in a population. CYP3A4*20 results together with the key role of CYP3A4 in drug metabolism support screening for rare CYP3A4 functional alleles among subjects with adverse drug events in certain populations.


Assuntos
Citocromo P-450 CYP3A/genética , Etnicidade/genética , Frequência do Gene/genética , Polimorfismo de Nucleotídeo Único/genética , Alelos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/genética , Efeito Fundador , Haplótipos/genética , Humanos
6.
Lett Appl Microbiol ; 57(5): 443-50, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-23848962

RESUMO

Cholesterol oxidation products (COPs) are a group of compounds formed during processing and storage of foods from animal origin. After ingestion, COPs are absorbed in the intestine and can be distributed to serum and various tissues, potentially promoting a variety of toxic effects. Therefore, inhibition of their intestinal absorption may contribute to reduce the health risks associated with dietary intake of COPs. Some studies have shown that drugs and dietary compounds may inhibit the intestinal absorption of dietary COPs. However, proven cholesterol- and/or food toxins-binding lactic acid bacteria have not been previously evaluated as potential COPs removal agents. The aim of this study was to assess the ability of Lactobacillus casei ATCC334 to remove COPs in aqueous solution. Results showed the ability of both growing and resting cells to remove COPs (ca. 30-60%). All COPs-bacterium interactions were specific and partly reversible, being resting cells the most efficient for COPs removal in a ranking order of 7-KC > 7α-OH/7ß-OH > triol > 5,6ß-EP > 5,6α-EP > 25-OH. Binding to the cell wall and/or cell membrane incorporation appears to be the most likely mechanisms involved on COPs removal by L. casei ATCC 334.


Assuntos
Colesterol/metabolismo , Lacticaseibacillus casei/metabolismo , Produtos da Carne/análise , Oxirredução , Animais
7.
Med Phys ; 37(2): 577-89, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20229866

RESUMO

This phantom study simulates contrast-medium-enhanced digital subtraction mammography (CEDM) and compares subtracted image quality and total mean glandular dose for two alternative spectral combinations available in a GE Senographe DS mammography unit. The first choice takes advantage of large iodine attenuation at low photon energies and uses traditionally available spectra (anode/filter combinations Mo/Mo at 25 kV and Rh/Rh at 40 kV, "Mo25-Rh40"). The second choice, selected from a previous analytical optimization, includes harder spectra obtained by adding external filtration to traditional beams (Rh/Rh at 34 kV and Rh/Rh+5 mm of Al at 45 kV, "Rh34-Rh45H"). Individual images of a custom-made phantom containing tubes of various diameters filled with water- or iodine-based contrast agent were acquired with both spectral combinations. The total breast entrance air kerma, considering subtraction of two images, was limited to 8.76 mGy (1 R). The results were compared to predictions obtained through an analytical formalism that assumes noise of stochastic origin. Individual images were evaluated and subtracted under five combinations of temporal and dual-energy modalities. Signal variance analysis in individual raw images showed important contributions of nonstochastic origin, associated with the software applied to raw images, the curved geometry, and strong attenuation of the phantom cylindrical iodine-filled tubes, causing experimental SNR to vary from 2.2 to 0.8 times the predictions from low to high values of SNR. Iodine contrast in the subtracted images was found to be mainly defined by the spectra, independent of exposure, and linearly dependent on the iodine mass thickness. The highest contrast was obtained with the combined dual-energy temporal subtraction with Rh34-Rh45H, its value was 7% larger than the highest value measured with Mo25-Rh40. As expected, temporal modalities (single and dual energy, any spectral choice) led to higher contrast-over-noise ratio (CNR) than nontemporal dual-energy subtraction, the latter being negligibly small with Mo25-Rh40. CNR for 4 mg iodine/cm2 imaged temporally in a dual-energy fashion with Rh34-Rh45H (iodine imaged at high energy) is about 1.7 times the optimum for Mo25-Rh40 (iodine imaged at low energy). Iodine thicknesses needed to fulfill Rose's criterion were 0.78 +/- 0.02 mg iodine/cm2 for Mo25-Rh40 and 0.54 +/- 0.17 mg iodine/cm2 for Rh34-Rh45H, both lower than the proposed biological concentration of iodine in breast tumors after contrast medium administration. Although similar dose levels were obtained with both spectral choices under dual-energy (temporal and nontemporal) subtraction, the dose obtained in single-energy temporal subtraction with the Mo25 spectrum was 1.2 mGy lower than the dose from the modality offering the highest CNR. In all results considered, the spectral choice Mo25-Rh40 was found to represent an interesting alternative to the use of high-energy hardened spectra for CEDM, particularly when performing dynamic studies of the contrast-agent uptake in breast lesions.


Assuntos
Iodo , Mamografia/instrumentação , Intensificação de Imagem Radiográfica/instrumentação , Imagem Radiográfica a Partir de Emissão de Duplo Fóton/instrumentação , Meios de Contraste , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Mamografia/métodos , Imagens de Fantasmas , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
8.
Eur Child Adolesc Psychiatry ; 19(7): 615-9, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20047063

RESUMO

Associations between cholesterol and suicidal behavior in adolescent patients have not been explored in depth. In this study, 66 patients consecutively admitted to a psychiatric inpatient unit following attempted suicide were compared with a control group of 54 patients with no history of suicide attempts. The age range of the sample was from 8 to 18 years old. Cholesterol levels were significantly lower in attempted suicide patients than in controls (p < 0.02), supporting the hypothesis that lower cholesterol levels might be associated with suicidal behavior in patients with similar acute phase of their disorder.


Assuntos
Colesterol/sangue , Hospitalização , Tentativa de Suicídio/psicologia , Adolescente , Estudos de Casos e Controles , Criança , Transtorno Depressivo/sangue , Transtorno Depressivo/psicologia , Feminino , Humanos , Masculino , Transtornos Mentais/sangue , Transtornos Mentais/psicologia , Valores de Referência , Estudos Retrospectivos , Fatores de Risco , Espanha
9.
Actas Esp Psiquiatr ; 38(3): 170-82, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21210322

RESUMO

OBJECTIVE: To review the literature covering the epidemiology, clinical characteristics, longitudinal course, prognosis and clues for the assessment of the Pediatrics Bipolar Disorder (PBD). METHOD: A computerized search in PubMed, looking for published articles since 1980. RESULTS: During the last years, the PBD diagnosis has proliferated largely, with some studies reporting incidences between 1% and 5%. In the past, some researchers reported that atypical symptoms could be more common than the classical symptoms in the PBD. However, current studies confirm the presence of typical mania symptoms in the youngest. Also, they confirm the utility of the diagnostic criteria DSM-IV in this population, with the PBD-NOS as the most prevalent phenotype. Those cases with irritability and without any other maniac symptom are still not clear, but the evidence shows a possible evolution towards others non-bipolar affective disorders. The PBD has high comorbidity, especially with ADHD and Disruptive Behavior Disorders. In the longitudinal evaluation, the PBD cases show high rates of relapse and persistent subsyndromical symptoms. The diagnosis is based in the clinical presentation, with collateral information provided by the family. Screening scales and standardized interview has been developed. CONCLUSIONS: Now days is possible the diagnosis of PBD, although there is not enough information about the categorization and the longitudinal course of the PBD. Future studies are needed in order to clarify these shadows.


Assuntos
Transtorno Bipolar/diagnóstico , Transtorno Bipolar/complicações , Transtorno Bipolar/epidemiologia , Criança , Diagnóstico Diferencial , Humanos , Prevalência , Prognóstico
10.
J Matern Fetal Neonatal Med ; 33(24): 4083-4089, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30880514

RESUMO

Background: Inflammation is a condition that jeopardizes the continuity of pregnancy because it increases the secretion of chemokines that favor the migration of leukocytes from maternal and fetal circulations to the cervix, placenta, and the chorioamniotic membranes. During pregnancy, the level of prolactin (PRL) in the amniotic fluid is high; there is evidence to suggest that PRL contributes to maintain a privileged immune environment in the amniotic cavity. We test the effect of prolactin on the secretion profile of chemokines in human fetal membranes.Methods: Nine fetal membranes collected from healthy nonlabouring cesarean deliveries at term. We placed whole membrane explants in a two-chamber culture system. Choriodecidua and amniotic chambers were pretreated with 250, 500, 1000, or 4000 ng/ml of PRL for 24 h, then choriodecidua was cotreated with 500 ng/ml of lipopolysaccharide (LPS) and PRL for 24 h. We used ELISA to measure secreted levels of four chemokines (RANTES, monocyte chemoattractant protein 1 (MCP-1), MIP-1α, and IL-8) in both amnion and choriodecidua regions.Results: In comparison with basal conditions, LPS treatment induced significantly higher secretion of RANTES, MCP-1, and MIP-1α, but not of IL-8. RANTES was mainly produced by choriodecidua and cotreatment with PRL significantly decreased its LPS-induced secretion. MCP-1 was primarily produced by the amnion and its secretion was only inhibited by 4000 ng/ml of PRL. Both membrane regions produced MIP-1α, which was significantly inhibited at 1000 and 4000 ng/ml PRL concentrations. IL-8 showed no significant changes regardless of PRL concentration.Conclusion: PRL inhibits the differential secretion of proinflammatory chemokines by human fetal membranes.


Assuntos
Membranas Extraembrionárias , Lipopolissacarídeos , Prolactina , Âmnio , Quimiocinas , Feminino , Humanos , Gravidez , Prolactina/fisiologia
11.
Brain ; 131(Pt 8): 2106-26, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18669492

RESUMO

The current transplantation paradigm for Parkinson's disease that places foetal dopaminergic cells in the striatum neither normalizes neuronal activity in basal ganglia structures such as the substantia nigra (SN) and subthalamic nucleus (STN) nor leads to complete functional recovery. It was hypothesized that restoration of parkinsonian deficits requires inhibition of the pathological overactivity of the STN and SN in addition to restoration of dopaminergic activity in the striatum. To achieve inhibition, a multitargeted basal ganglia transplantation strategy using GABAergic cells derived from either foetal striatal primordia (FSP) cells or human neural precursor cells (hNPCs) expanded in suspension bioreactors was investigated. In hemiparkinsonian rats, transplantation of foetal rat dopaminergic cells in the striatum in conjunction with GABAergic grafts in the STN and/or SN promoted significant improvement in forelimb akinesia and motor function compared to transplantation of intrastriatal dopaminergic grafts alone or in conjunction with undifferentiated hNPCs. In culture, FSP cells exhibited neuronal electrophysiological properties. However, recordings from GABAergic hNPCs revealed limited ionic conductances and an inability to fire action potentials. Despite this, they were almost as efficacious as FSP cells in inducing functional recovery following transplantation, suggesting that such recovery may have been mediated by secretion of GABA rather than by functional integration into the host. Thus, restoration of dopaminergic activity to the striatum in concert with inhibition of the STN and SN by GABAergic grafts may be beneficial for improving clinical outcomes in patients with Parkinson's disease and potential clinical application of this strategy may be enhanced by the use of differentiated hNPCs.


Assuntos
Gânglios da Base/metabolismo , Células-Tronco Fetais/transplante , Neurônios/transplante , Transtornos Parkinsonianos/cirurgia , Animais , Dopamina/metabolismo , Feminino , Humanos , Imuno-Histoquímica , Microscopia Confocal , Modelos Animais , Testes Neuropsicológicos , Transtornos Parkinsonianos/metabolismo , Distribuição Aleatória , Ratos , Ratos Wistar , Substância Negra , Núcleo Subtalâmico , Resultado do Tratamento , Ácido gama-Aminobutírico/metabolismo
13.
Eur J Neurosci ; 27(1): 43-52, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18093176

RESUMO

Although neural transplantation of fetal dopaminergic cells is a promising therapy for Parkinson's disease, poor transplanted cell survival limits its efficacy. In the present study it was hypothesized that the use of Poloxamer 188 (P188), a non-ionic surfactant, during cell preparation and transplantation may protect cells from associated mechanical injury and thus improve transplanted cell survival in a rat model of Parkinson's disease. Fetal rat dopaminergic tissue was dissociated in media with or without P188 and then cultured for 1 week or transplanted into the striatum of rats with unilateral 6-hydroxydopamine lesions of the nigrostriatal dopaminergic pathway. Fetal dopaminergic cell survival and reinnervation of the host brain were examined using tyrosine hydroxylase immunohistochemistry and stereological quantification. The number of surviving tyrosine hydroxylase-immunoreactive cells in vitro and in vivo was significantly increased by 2.2-fold by incubating fetal dopaminergic cells with P188 during tissue dissociation. Furthermore, the striatal reinnervation in parkinsonian rats that received intrastriatal transplants of P188-exposed dopaminergic cells was significantly enhanced (1.8-fold increase) compared with rats that received non-P188-treated cells. In conclusion, P188 protects fetal dopaminergic cells from mechanical injury by increasing cell survival and enhances dopaminergic fibre outgrowth into the transplanted striatum. Use of P188 may thus be an important adjunct to improve the clinical efficacy of neural transplantation for Parkinson's disease.


Assuntos
Transplante de Células/métodos , Neurônios/efeitos dos fármacos , Doença de Parkinson/cirurgia , Poloxâmero/farmacologia , Tensoativos/farmacologia , Anfetamina , Análise de Variância , Animais , Comportamento Animal/efeitos dos fármacos , Comportamento Animal/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Dopamina/metabolismo , Inibidores da Captação de Dopamina , Embrião de Mamíferos , Feminino , Técnicas In Vitro , Mesencéfalo/citologia , Fibras Nervosas/efeitos dos fármacos , Fibras Nervosas/fisiologia , Oxidopamina/toxicidade , Doença de Parkinson/etiologia , Doença de Parkinson/fisiopatologia , Ratos , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
14.
Med Phys ; 35(12): 5544-57, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19175112

RESUMO

Contrast-medium-enhanced digital mammography (CEDM) is an image subtraction technique which might help unmasking lesions embedded in very dense breasts. Previous works have stated the feasibility of CEDM and the imperative need of radiological optimization. This work presents an extension of a former analytical formalism to predict contrast-to-noise ratio (CNR) in subtracted mammograms. The goal is to optimize radiological parameters available in a clinical mammographic unit (x-ray tube anode/filter combination, voltage, and loading) by maximizing CNR and minimizing total mean glandular dose (D(gT)), simulating the experimental application of an iodine-based contrast medium and the image subtraction under dual-energy nontemporal, and single- or dual-energy temporal modalities. Total breast-entrance air kerma is limited to a fixed 8.76 mGy (1 R, similar to screening studies). Mathematical expressions obtained from the formalism are evaluated using computed mammographic x-ray spectra attenuated by an adipose/glandular breast containing an elongated structure filled with an iodinated solution in various concentrations. A systematic study of contrast, its associated variance, and CNR for different spectral combinations is performed, concluding in the proposal of optimum x-ray spectra. The linearity between contrast in subtracted images and iodine mass thickness is proven, including the determination of iodine visualization limits based on Rose's detection criterion. Finally, total breast-entrance air kerma is distributed between both images in various proportions in order to maximize the figure of merit CNR2/D(gT). Predicted results indicate the advantage of temporal subtraction (either single- or dual-energy modalities) with optimum parameters corresponding to high-voltage, strongly hardened Rh/Rh spectra. For temporal techniques, CNR was found to depend mostly on the energy of the iodinated image, and thus reduction in D(gT) could be achieved if the spectral energy of the noniodinated image is decreased and the breast-entrance air kerma is evenly distributed between both acquisitions. Predicted limits, in terms of iodine concentration, are found to guarantee the visualization of common clinical angiogenic concentrations in the breast.


Assuntos
Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/diagnóstico , Meios de Contraste/farmacologia , Mamografia/métodos , Interpretação de Imagem Radiográfica Assistida por Computador/métodos , Tecido Adiposo/patologia , Mama/patologia , Desenho de Equipamento , Feminino , Humanos , Radioisótopos do Iodo , Modelos Estatísticos , Neovascularização Patológica , Processamento de Sinais Assistido por Computador , Técnica de Subtração , Fatores de Tempo
15.
An Pediatr (Barc) ; 68(1): 49-53, 2008 Jan.
Artigo em Espanhol | MEDLINE | ID: mdl-18194628

RESUMO

INTRODUCTION: Postvaricella cerebellar ataxia (PVCA) and meningoencephalitis are the most common acute neurological complications of chickenpox. The objective of this study was to describe the clinical presentation, management, and outcome of children hospitalized with PVCA in the only pediatric hospital of this developing country, where routine varicella immunization is not yet available. METHODS: We performed a retrospective chart review of children aged 1-12 years old admitted to the National Children's Hospital of Costa Rica from January 1997 to June 2004 with a diagnosis of PVCA. RESULTS: Among the 441 immunocompetent patients admitted for varicella zoster virus-associated complications during this period, 37 (8.4%) had PVCA. Twenty-four of the 37 (64.9%) patients were boys. The mean (range) age was 5 (1-10) years. The median (range) interval from rash onset to admission was 2 (1-3) days. Cerebrospinal fluid analysis was available in 22 (59.5%) patients and was normal in all. Head computed tomography showed cerebral edema in six out of 18 patients (33.3%). Intravenous acyclovir was administered to 23 patients but no significant differences in clinical manifestations or outcomes were observed in treated versus untreated patients. The mean (range) length of ataxia was 4 (1-10) days, and seven (19%) patients were still ataxic on discharge. The mean (range) length of hospital stay was 4.4 (2-11) days. Minor sequelae were documented in 13 out of 24 (54.2%) patients during follow-up visits and telephone contacts. CONCLUSIONS: PVCA is usually associated with a favorable prognosis; however, neurological sequelae can occur. The real utility of acyclovir treatment and brain imaging studies in these children remains controversial.


Assuntos
Ataxia Cerebelar/etiologia , Varicela/complicações , Ataxia Cerebelar/diagnóstico , Ataxia Cerebelar/terapia , Criança , Pré-Escolar , Costa Rica , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
16.
Phys Med Biol ; 63(17): 175013, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30101754

RESUMO

The main objective of multichannel radiochromic film dosimetry methods is to correct, or at least mitigate, spatial heterogeneities in the film-scanner response, especially variations in the active layer thickness. To this end, films can also be scanned prior to irradiation. In this study, the abilities of various single channel and multichannel methods to reduce spatial heterogeneities, with and without scanning before irradiation, were tested. Red, green and blue single channel models, two additive channel independent perturbation (CHIP) models and two multiplicative CHIP models were compared with the Multigaussian method. The Multigaussian method is a new approach to multichannel dosimetry, based on experimental findings. It assumes that the probability density function of the response vector formed by the pixel values of the different color channels, including irradiated and non-irradiated scans, follows a multivariate Gaussian distribution. The Multigaussian method provided more accurate doses than the other models under comparison, especially when incorporating the information of the film prior to irradiation. The relative dose differences between reference doses measured with MatriXX and film doses were examined. After applying inter-scan and lateral corrections, the lowest mean absolute errors were 0.8% and 1.0% for the Multigaussian method with and without the information of the scan before irradiation, respectively. Followed by the uniform multiplicative CHIP and red single channel models, using pixel values and net optical density, respectively, both with 1.1%.


Assuntos
Calibragem , Dosimetria Fotográfica/métodos , Modelos Teóricos , Cor , Doses de Radiação
17.
Neuroscience ; 147(3): 712-9, 2007 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-17583436

RESUMO

Glial cell-line derived neurotrophic factor (GDNF) enhances dopamine (DA) cell survival and fiber outgrowth, and may be beneficial in enhancing cell restorative strategies for Parkinson's disease (PD). However, GDNF may have different roles for transplanted DA cell sub-types. The present in vitro study investigated the effect of GDNF on the survival of rat DA cells displaying a phenotype consistent with either the substantia nigra [A9 cells immunopositive for tyrosine hydroxylase (TH) and G-protein-gated inwardly rectifying potassium channel subunit 2 (GIRK2)] or with the ventral tegmental area [A10 cells immunopositive for TH and calbindin]. It was found that a single exposure of GDNF enhanced the number of DA cells of an A9 phenotype, without affecting DA cells of an A10 phenotype. Conversely, repeated GDNF exposure did not alter the survival of A9 phenotypic cells, but doubled the percentage of A10 cells. It was concluded that GDNF administration may affect dopaminergic cells differently depending on time and degree of GDNF exposure. For cell transplantation in PD, long-term GDNF administration may result in detrimental effects for transplanted A9 TH+ cells as this may introduce competition with A10 TH+ cells for survival and fiber outgrowth into the host striatum. These results may have important implications for clinical neural transplantation in PD.


Assuntos
Diferenciação Celular/efeitos dos fármacos , Dopamina/metabolismo , Fator Neurotrófico Derivado de Linhagem de Célula Glial/farmacologia , Neurônios/efeitos dos fármacos , Substância Negra/citologia , Área Tegmentar Ventral/citologia , Animais , Calbindinas , Contagem de Células/métodos , Células Cultivadas , Embrião de Mamíferos , Embrião não Mamífero , Feminino , Canais de Potássio Corretores do Fluxo de Internalização Acoplados a Proteínas G/metabolismo , Gravidez , Ratos , Proteína G de Ligação ao Cálcio S100/metabolismo , Tirosina 3-Mono-Oxigenase/metabolismo
18.
Neuroscience ; 146(1): 213-24, 2007 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-17303340

RESUMO

Immunosuppression remains a key issue in neural transplantation. Systemic administration of cyclosporin-A is currently widely used but has many severe adverse side effects. Newer immunosuppressive agents, such as tacrolimus (TAC) and rapamycin (RAPA), have been investigated for their neuroprotective properties on dopaminergic neurons. These drugs have been formulated into liposomal preparations [liposomal tacrolimus (LTAC) and liposomal rapamycin (LRAPA)] which retain these neuroprotective properties. Due to the slower release of the drugs from the liposomes, we hypothesized that co-transplantation of either LTAC or LRAPA within a xenogeneic cell suspension would increase cell survival and decrease graft rejection in the hemiparkinsonian rat, and that a combination of the two drugs may have a synergistic effect. 6-hydroxydopamine-lesioned rats were divided to four groups which received intra-striatal transplants of the following: 1) a cell suspension containing 400,000 fetal mouse ventral mesencephalic cells; 2) the cell suspension containing 0.63 microM LRAPA; 3) the cell suspension containing a dose of 2.0 microM LTAC; 4) the cell suspension containing 2.0 microM LTAC and 0.63 microM LRAPA. Functional recovery was assessed by amphetamine-induced rotational behavior. Animals were killed at 4 days or 6 weeks post-transplantation, and immunohistochemistry was performed to look at the expression of tyrosine hydroxylase and major histocompatibility complex classes I and II. Only the group receiving LTAC had a decrease in rotational behavior. This observation correlated well with significantly more surviving tyrosine hydroxylase immunoreactive cells compared with the other groups and significantly lower levels of immunorejection as assessed by major histocompatibility complex class I and II staining. This study has shown the feasibility of using local immunosuppression in xenotransplantation. These findings may be useful in optimizing immunosuppression in experimental neural transplantation in the laboratory and its translation into the clinical setting.


Assuntos
Imunossupressores/uso terapêutico , Lipossomos/metabolismo , Transtornos Parkinsonianos/tratamento farmacológico , Transtornos Parkinsonianos/cirurgia , Tacrolimo/uso terapêutico , Transplante Heterólogo/métodos , Análise de Variância , Animais , Antígenos CD/metabolismo , Comportamento Animal , Transplante de Células/métodos , Modelos Animais de Doenças , Embrião de Mamíferos , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Atividade Motora/efeitos dos fármacos , Atividade Motora/fisiologia , Oxidopamina , Transtornos Parkinsonianos/induzido quimicamente , Transtornos Parkinsonianos/patologia , Ratos , Fatores de Tempo , Tirosina 3-Mono-Oxigenase/metabolismo
19.
Mol Cell Biol ; 17(4): 2177-85, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9121467

RESUMO

The delineation of molecular structures that dictate Src homology 3 (SH3) domain recognition of specific proline-rich ligands is key to understanding unique functions of diverse SH3 domain-containing signalling molecules. We recently established that assembly of the phagocyte NADPH oxidase involves multiple SH3 domain interactions between several oxidase components (p47phox, p67phox, and p22phox). p47phox was shown to play a central role in oxidase activation in whole cells by mediating interactions with both the transmembrane component p22phox and cytosolic p67phox. To understand the specific roles of each SH3 domain of p47phox in oxidase assembly and activation, we mutated critical consensus residues (Tyr167 or Tyr237-->Leu [Y167L or Y237L], W193R or W263R, and P206L or P276L) on each of their binding surfaces. The differential effects of these mutations indicated that the first SH3 domain is responsible for the p47phox-p22phox interaction and plays a predominant role in oxidase activity and p47phox membrane assembly, while the second p47phox SH3 domain interacts with the NH2-terminal domain of p67phox. Binding experiments using the isolated first SH3 domain also demonstrated its involvement in intramolecular interactions within p47phox and showed a requirement for five residues (residues 151 to 155) on its N-terminal boundary for binding to p22phox. The differential effects of nonconserved-site mutations (W204A or Y274A and E174Q or E244Q) on whole-cell oxidase activity suggested that unique contact residues within the third binding pocket of each SH3 domain influence their ligand-binding specificities.


Assuntos
Proteínas de Membrana Transportadoras , NADPH Oxidases/metabolismo , Fosfoproteínas/química , Fosfoproteínas/metabolismo , Sequência de Aminoácidos , Sítios de Ligação/genética , Linhagem Celular , Ativação Enzimática , Humanos , Ligantes , Modelos Biológicos , Dados de Sequência Molecular , Estrutura Molecular , Mutagênese Sítio-Dirigida , NADPH Desidrogenase/química , NADPH Desidrogenase/genética , NADPH Desidrogenase/metabolismo , Fosfoproteínas/genética , Homologia de Sequência de Aminoácidos , Superóxidos/metabolismo , Domínios de Homologia de src
20.
Can Commun Dis Rep ; 43(6): 120-124, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-29770076

RESUMO

BACKGROUND: Saskatchewan is a province of over one million people and over 13% are Indigenous peoples, many of whom live on reserve lands. Despite continued efforts, access to health care remains a significant challenge for these Indigenous people, especially those in the North. OBJECTIVE: To address this challenge, Saskatchewan's health care providers have been incorporating the use of technology for various health services. This paper describes various ways technology has been used in First Nations communities in Saskatchewan. METHODS: Several pilot projects between First Nations leaders and health care providers, in the communities as well as in the urban setting, have taken place over the past 10 years. Information on these pilots was supplemented with literature reviews and consultations with colleagues at the Northern Inter-Tribal Health Authority, the First Nations and Inuit Health Branch (FNIHB), Health Canada and lead physicians for services to the North. RESULTS: Numerous technologies have shown promise in aiding the timely delivery of high quality health care. Remote Presence Robotic Technology (RPRT) is a form of telemedicine that creates the sense that a clinician is at the patient's side; enabling clinical services to be provided remotely and in real time. Increasing access to internet services and providing computer tablets to community health nurses have improved patients' access to clinical care and to vital health care information. Robotic ultrasonography has been used to provide onsite care for pre-natal patients. The provision of cell phones to HIV-positive patients has improved compliance with anti-retroviral therapy and has resulted in better clinical outcomes. The Xpert MTB/RIF (Mycobacerium tuberculosis complex / resistance to rifampicin) is an automated device that, through analysis of raw sputum samples, can identify the presence of M. tuberculosis with greater speed, sensitivity and specificity than the conventional acid-fast bacilli (AFB) smear. Similarly, telemedicine remote communications equipment is being used for patient care across communities. Panorama is a comprehensive, integrated public health information system designed for public health professionals and is currently being introduced in 21 communities in Saskatchewan. CONCLUSION: Not only do these innovative technologies appear to improve access and enhance the quality of timely care in remote communities but they also bring comfort to patients, prevent unnecessary transportation and minimize time away from work and family. Although these technologies are not a panacea for some of the determinants of health that can affect the incidence and severity of infectious diseases in First Nations, they do appear to address some of the geographic challenges faced in providing health services in remote communities.

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