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1.
Chimia (Aarau) ; 77(11): 773-776, 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38047845

RESUMO

The present paper introduces soil as a complex system, so a multidisciplinary approach is needed to study not only the composition, abundance, and transport of microplastics (MPs) in terrestrial ecosystems but also soil properties and processes involved in their degradation and/or interaction with soil polyphasic matrix. Despite many researchers focusing their studies on the impact of MPs on the terrestrial ecosystem over the past years, little has been done about the use of biochemical indicators to study their effect on soil functionality.


Assuntos
Ecossistema , Microplásticos , Plásticos , Estudos Interdisciplinares
2.
Eur Rev Med Pharmacol Sci ; 25(22): 6874-6880, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34859849

RESUMO

Scientific and technological advances in the diagnosis of neoplastic disease and the introduction of increasingly accurate and personalized anti-cancer treatments have significantly improved the chances of survival of most cancer patients, particularly at a young age. Since the interest of the research community in the life prospects of young cancer survivors has been growing, a new branch of medicine has emerged in recent years that reconciles the potentially gonadotoxic treatments of cancer with the preservation of fertility: oncofertility. The possibility of preserving one's fertility can be of great benefit for the psychological well-being of cancer patients, whose mental health is already severely tested by the cancer diagnosis. Although national and international guidelines urge doctors to start early a discussion on fertility conservation issues (reproductive counseling), still little is known as to the awareness of oncofertility by young cancer survivors and the information they receive about it.


Assuntos
Sobreviventes de Câncer , Aconselhamento , Preservação da Fertilidade , Fertilidade , Humanos , Neoplasias/terapia
3.
Talanta ; 190: 167-173, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-30172494

RESUMO

Although arsenic (As) toxicity in soil vary depending on its chemical forms and oxidation states, regulatory limits for this compartment rely on total As content. Conventional methods of total As determination are expensive and time-consuming. The development of predictive techniques might enable a speditive assessment of As contamination in those scenarios, such as thermal spring sites, where exposure to the metalloid poses a threat to human health. The objective of this study was to assess the suitability of Visible Near Infrared spectrophotometry for predicting the total As content in highly calcareous thermal spring soils and the same aim was pursued for those elements (i.e. Al, Fe and Mn) the chemistry of which is tightly connected with that of As. A Partial Least Square approach, including cross-validation and external independent test, was used to relate the concentrations of the target elements to spectral data. The most accurate prediction was found for As with Pearson's coefficient, RMSE, RPD and SEP being equal to 0.94, 69.65, 2.9 and 66.99, respectively. Less accurate predictions were found for Al (r = 0.88; RMSE = 11014; RPD = 1.96; SEP = 11014), Fe (r = 0.93; RMSE = 6921.1; RPD = 2.45; SEP = 6462.4), and Mn (r = 0.92; RMSE = 542.01; RPD = 2.43; SEP = 529.79).

4.
J Neurol Sci ; 368: 402-7, 2016 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-27538672

RESUMO

BACKGROUND: 4-aminopyridine (4-AP) is a potassium-channel blocker able to enhance walking speed in MS improving the action potentials of demyelinated axons on which internodal potassium channels are exposed. OBJECTIVE: to study early 4-AP effect with clinical, subjective, neurophysiological and neuroradiological tools. METHODS: Clinical (Timed 25-Foot Walk - T25FW, Timed Up-And-Go - TUG), subjective (MS Walking Scale-12 - MSWS-12), neurophysiological (Motor Evoked Potentials - MEPs) and imaging (Diffusion Tensor Imaging - DTI) evaluations were performed before (T0) and after (T1) 14days of 4-AP treatment. MEPs were recorded from Abductor Hallucis of both legs. A Tract-Based-Spatial-Statistics (TBSS) was performed on DTI. RESULTS: We found a significant difference between T0 and T1 for T25FW, TUG, MSWS-12 (p≤0.001) in the whole patients' sample (23 subjects, median EDSS 6.0) and decrease of Central Motor Conduction Time and increase of mean Amplitude (Amp) at T1 (p=0.008 and p=0.006). We also recorded a significant difference of T25FW, TUG, MSWS-12 and Amp in clinical responder (CR) patients (CR: amelioration >20% at T25FW). TBSS showed a significant Mean and Radial Diffusivity reduction in the corticospinal tracts (p<0.05) of the whole group of patients; this reduction was also found in the CR subgroup. CONCLUSION: Neurophysiological and neuroradiological parameters were modified in MS patients treated with 4-AP, and most of them reported a subjective improvement of their motor performances after treatment. The use of clinical, subjective, neurophysiological and neuroradiological tools could help to better explore MS patients responsiveness to 4-AP.


Assuntos
4-Aminopiridina/uso terapêutico , Esclerose Múltipla/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde/métodos , Bloqueadores dos Canais de Potássio/uso terapêutico , Adulto , Imagem de Tensor de Difusão , Potencial Evocado Motor/efeitos dos fármacos , Teste de Esforço , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/fisiopatologia , Índice de Gravidade de Doença , Estatística como Assunto , Estatísticas não Paramétricas , Estimulação Magnética Transcraniana , Caminhada/fisiologia
5.
Acta Neurol Scand ; 132(4): 226-34, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25690402

RESUMO

OBJECTIVE: Multiple sclerosis (MS) affects young adults of working age. Difficulties in work-related activities are usually ascribed to MS symptoms, while the impact of workplace features is underestimated. This article presents the Multiple Sclerosis Questionnaire for Job Difficulties (MSQ-Job), designed to assess working difficulties due to MS symptoms and workplace features. METHODS: A sample of employed MS patients completed the MSQ-Job, the WHO-Disability Assessment Schedule (WHODAS 2.0) and the 54-items MS Quality of Life Questionnaires (MSQOL-54); the expanded disability status scale (EDSS) was used to define MS severity. Factor structure was evaluated using principal component extraction and Oblimin rotation; internal consistency was assessed with Cronbach's alpha; construct and discriminant validity using t-test (EDSS 0-2 vs >2; patients self-reporting need for support vs patients reporting no needs; full-time vs part-time employees); and Pearson's correlation with WHODAS 2.0 and MSQOL-54. RESULTS: The MSQ-Job is a 42-item questionnaire with six scales and an overall factor. Scores range on a 0-100 scale (higher scores indicate more and more severe difficulties); patients with EDSS>2 and self-reporting support needs had worse scores than those with EDSS 0-2 and without needs. Correlations with WHODAS 2.0 and MSQOL-54 were generally significant (P < 0.0007) and below 0.70. CONCLUSIONS: The MSQ-Job jointly measures the impact of respondents' symptoms and workplace features on work activities and enables to assess the effects of clinical and occupational interventions and better describe the impact of MS indirect costs.


Assuntos
Esclerose Múltipla/psicologia , Autorrelato/normas , Trabalho , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/economia , Qualidade de Vida , Adulto Jovem
6.
Ecotoxicol Environ Saf ; 96: 147-53, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23856118

RESUMO

Three soils, coming from a former mining site and characterized by a different degree of pollution, were analysed in terms of Arsenic (As) content, using three different analytical approaches, and its distribution in various soil fractions. The effect of As on soil microbial biomass (size, respiration and microbial quotients) was also analysed. Total arsenic concentration between soil fractions was significantly different and ranged from 189 to 4357mgkg(-1), indicating a high level of pollution. Soil sequential fractioning showed that more than 60 percent of total As was bound to Fe-Al oxides, suggesting a minor availability and environmental risk regardless the total concentration of As in the sample. On the contrary, water soluble As fraction showed a significant difference among the three samples. The largest water soluble As concentration was found in the sample with intermediate total As amount. As far as microbial biomass is concerned, it was found that bioavailable As negatively impacted microbial metabolism in terms of basal and cumulative respiration, and microbial quotients, suggesting a strong selection within microbial pool.


Assuntos
Arsênio/análise , Mineração , Microbiologia do Solo , Poluentes do Solo/análise , Solo/química , Arsênio/toxicidade , Bactérias/efeitos dos fármacos , Bactérias/metabolismo , Biomassa , Monitoramento Ambiental , Itália , Poluentes do Solo/toxicidade
7.
Epilepsia ; 47 Suppl 2: 76-8, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17105468

RESUMO

PURPOSE: We reviewed the clinical charts of 22 patients (mean age 12 years) with idiopathic occipital lobe epilepsies (IOLE) to verify the presence of visuoperceptual difficulties. METHODS: All 22 patients underwent a standard neuropsychiatric examination and had a sleep electroencephalogram (EEG). Eleven had normal development and adequate scholastic achievements, so no formal testing was performed. Psychological assessment was carried out in the remaining 11 patients who had been referred because of learning and behavioral difficulties. RESULTS AND CONCLUSIONS: IQ was in the average/low-average range in most patients, with a cognitive profile characterized by relatively better verbal than performance abilities (8/11). There was a high incidence of scholastic disabilities (7/11); psychiatric disorders in the form of anxiety and depressive disorders were also frequent (6/11). In the six patients who had neuropsychological assessment with specific visuoperceptual testing, a deficit in facial discrimination was found in four patients, associated with a line orientation deficit in three. Although preliminary, and based on a tertiary-care clinical sample, these data suggest that children with IOLE, are at risk for lower intellectual performance, poor scholastic achievement and psychiatric disorders, as well as for specific deficits in the visuoperceptual domain, probably due to dysfunction of the occipitotemporal circuitries most often involved in seizure spread in epilepsies originating in the posterior brain.


Assuntos
Transtornos Cognitivos/diagnóstico , Epilepsias Parciais/diagnóstico , Testes Neuropsicológicos/estatística & dados numéricos , Logro , Criança , Eletroencefalografia/estatística & dados numéricos , Feminino , Humanos , Deficiências da Aprendizagem/diagnóstico , Masculino , Transtornos Mentais/diagnóstico , Transtornos da Percepção/diagnóstico , Prosopagnosia/diagnóstico , Fatores de Risco , Sono/fisiologia
8.
Sci Total Environ ; 372(1): 256-65, 2006 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17023027

RESUMO

Soil carbon (C) long term storage is influenced by the balance among ecosystem net primary productivity (NPP), the rate of delivery of new organic matter to soil pools and the decomposition of soil organic matter (SOM). The increase of NPP under elevated CO(2) can result in a greater production and higher turnover of fine roots or root exudation and, in turn, in an increase of labile C belowground. The aim of this work was to detect if changes in labile C substrates influenced the organic C storage in soils, verifying (i) whether treatments with elevated CO(2) and N fertilization induced changes in the amount and quality of labile C pools and in microbial C immobilization and (ii) whether these changes provoked modifications in the microbial C mineralization activity, and therefore changes in soil C losses. The effect of elevated CO(2) was a significant increase in both seasons (June and October 2004), of all labile C fractions: microbial biomass C (MBC), K(2)SO(4) extractable C (ExC), and water soluble C (WSC). The C/N ratio of the microbial biomass and of the K(2)SO(4) extractable SOM presented a seasonal fluctuation showing higher values in June, whereas the elevated CO(2) increased significantly the C/N ratio of these fractions independent of the season and the N addition, indicating a lower quality of labile SOM. Microbial respiration was more than doubled in October compared to June, confirming that changes in substrate quality and nutrient availability, occurring in the plantation at the beginning and at the end of the vegetative period, influenced the microbial activity in the bulk soil. Furthermore, the microbial respiration response to N fertilization was dependent on the season, with an opposite effect between June and October. The kinetic parameters calculated according to the first-order equation C(m)=C(0)(1-e(-kt)) were unaffected by elevated CO(2) treatment, except C(0)k and MR(basal), that showed a significant reduction, ascribable to (i) a lower quality of labile pools, and (ii) a more efficient microbial biomass in the use of available substrates. The C surplus found in elevated CO(2) soils was indeed immobilized and used for microbial growth, thus excluding a priming effect mechanism of elevated CO(2) on SOM decomposition.


Assuntos
Dióxido de Carbono/farmacologia , Carbono/análise , Fertilizantes , Nitrogênio/farmacologia , Microbiologia do Solo , Nitratos/análise , Populus , Compostos de Amônio Quaternário/análise , Solo
9.
Med Lav ; 97(1): 5-12, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-17009665

RESUMO

BACKGROUND: The rising awareness of psychological harassment at the workplace means that it is ever more important to collect clinical data and test tools to assess psychiatric disease connected with this phenomenon. OBJECTIVES: The aim of the study was to assess the experience gained by the centre for work maladjustment of the University Hospital of Pisa on a sample of patients, using the methods proposed by the centre at the Clinica del Lavoro "Luigi Devoto". MATERIALS AND METHODS: The patients were submitted to a diagnostic protocol consisting of work history, medical examination, psychological assessment, psychiatric examination, subjective questionnaires, mood scale and Neutest. The analysis was made in two phases in which 109 subjects were examined to check occupational stress effects in the period March 2002 - July 2004, after which 50 subjects were selected (45.9%) with the adaptation disorder and a history of adverse working conditions. RESULTS: The data gathered showed a slight predominance of workers from the public administration sector. The most representative range of duration of the psychological violence varied from 6 months to 2 years (46%). From close examination of the causes of the maladjustment disorders, structural changes in organization appeared to be the most frequent (13 cases). Among patients with positive diagnosis of disorder caused by psychological violence at the workplace, three situations were prominent: attitude to being a social outcast, behaviour to ignore proposals, and professional declassing. CONCLUSIONS: The multidisciplinary approach was culturally very stimulating and fundamental in reaching a final diagnosis of occupational disease: diagnosis of bullying at work and related disease was possible only thanks to the fact that three specialists agreed on the aetiological role of psychological harassment at the workplace. Our experience confirms that psychological harassment can cause health impairment and the most common diagnosis is maladjustment disorder.


Assuntos
Doenças Profissionais/epidemiologia , Comportamento Social , Estresse Psicológico/epidemiologia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças Profissionais/etiologia , Estresse Psicológico/etiologia , Inquéritos e Questionários
10.
J Appl Biomater Biomech ; 4(3): 165-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-20799202

RESUMO

The long-term survival of total joint prostheses is influenced by many factors. Among these factors, the most critical one is the presence of wear debris, particularly from the joint articulating surfaces. While ultra high molecular weight polyethylene (UHMWPE) has shown to be extremely promising in vitro and short-term clinical results, shelf-aged, oxidized components have been extremely unsuccessful clinically. Although shelf-aged components have been frequently tested in the laboratory, few studies have compared the properties of clinical retrievals to shelf-aged UHMWPE components. In this study, a thorough analysis method was developed and applied to both UHMWPE components retrieved at the time of revision, and non-implanted, shelf-aged UHMWPE components with the aim to understand better the significance of the in vivo factors on the material properties of the retrievals. The UHMWPE components were analyzed and characterized by visual observation of the surfaces, mechanical properties were assessed by small punch tests, wear resistance was analyzed by a multidirectional pin-on-disk test, and the oxidation level was detected by the Fourier transformed infrared (FT-IR) technique. The results indicated a strong correlation between the UHMWPE oxidation level, mechanical properties and wear resistance.

11.
Tree Physiol ; 25(11): 1399-408, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16105807

RESUMO

A high-density plantation of three genotypes of Populus was exposed to an elevated concentration of carbon dioxide ([CO(2)]; 550 micromol mol(-1)) from planting through canopy closure using a free-air CO(2) enrichment (FACE) technique. The FACE treatment stimulated gross primary productivity by 22 and 11% in the second and third years, respectively. Partitioning of extra carbon (C) among C pools of different turnover rates is of critical interest; thus, we calculated net ecosystem productivity (NEP) to determine whether elevated atmospheric [CO(2)] will enhance net plantation C storage capacity. Free-air CO(2) enrichment increased net primary productivity (NPP) of all genotypes by 21% in the second year and by 26% in the third year, mainly because of an increase in the size of C pools with relatively slow turnover rates (i.e., wood). In all genotypes in the FACE treatment, more new soil C was added to the total soil C pool compared with the control treatment. However, more old soil C loss was observed in the FACE treatment compared with the control treatment, possibly due to a priming effect from newly incorporated root litter. FACE did not significantly increase NEP, probably as a result of this priming effect.


Assuntos
Populus/fisiologia , Árvores/fisiologia , Biomassa , Dióxido de Carbono , Raízes de Plantas/fisiologia , Solo
12.
Plant Dis ; 88(1): 23-28, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30812451

RESUMO

Blue mold caused by Penicillium spp. is the most important postharvest disease of apple in Uruguay. Fourteen isolates of Penicillium were recovered from rotten apple and pear fruit with blue mold symptoms, and from water from flotation tanks in commercial apple juice facilities. Phenotypic identification to species level was performed, and the isolates were tested for sensitivity to commonly used postharvest fungicides. Genetic characterization of the isolates was performed with restriction fragment length polymorphism of the region including the internal transcribed spacer (ITS) ITS1 and ITS2 and the 5.8SrRNA gene (ITS1-5.8SrRNA gene-ITS2) ribosomal DNA region and with random amplified polymorphic DNA (RAPD) primers. Both techniques were able to differentiate these isolates at the species level. RAPD analysis proved to be an objective, rapid, and reliable tool to identify Penicillium spp. involved in blue mold of apple. In all, 11 isolates were identified as Penicillium expansum and 3 as P. solitum. This is the first report of P. solitum as an apple pathogen in Uruguay.

13.
J Appl Biomater Biomech ; 2(1): 20-8, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-20803447

RESUMO

New crosslinked ultra high molecular weight polyethylenes (UHMWPEs) have recently been developed, characterized and introduced in clinical applications. UHMWPE cross-linking treatments are very promising for reducing osteolysis induced by wear debris. The irradiation type, gamma or beta, the dosage and the thermal treatment performed during or following the irradiation process are all factors affecting polyethylene wear resistance. Thermal stabilization treatments performed after or during the irradiation process at a temperature above melting point (i.e. >130 degrees C) have been proven to effectively remove the free radicals generated during irradiation from UHMWPE, but their effect on the mechanical properties of UHMWPE are not completely clear. In addition to wear rate reduction, maintaining good mechanical properties is fundamental aspect in designing the new generation of crosslinked UHMWPE for artificial load bearing materials, especially considering the application in total knee replacements. In this study, we investigated the influence of different stabilization treatments, performed after gamma irradiation, on structural, wear and mechanical properties of UHMWPE. We performed four different stabilization treatments, with different temperatures and cooling rates, on 100 kGy gamma irradiated UHMWPE. Structural properties of UHMWPE were assessed by differential scanning calorimetry (DSC). To assess the mechanical performance of the materials, uni-axial tensile tests were performed according to the ASTM D638 standard, bi-axial tension performance was evaluated by small punch tests (ASTM F2183-02), toughness resistance was evaluated by the Izod method (ASTM F648), and cold flow resistance was analysed by a dynamic compressive test. Evaluation of wear resistance was by a multidirectional pin-on-disk screening machine. Materials considered were in ""aged"" and ""non-aged"" conditions. Results confirmed that cross-linking greatly enhances UHMWPE wear resistance, but introduces some detrimental effects on the mechanical properties. In this study, we found that the negative ef-fects on the mechanical properties of crosslinked UHMWPE can be modulated, to some extent, by choosing a thermal stabiliza-tion treatment at a correct temperature and cooling rate. (Journal of Applied Biomaterials & Biomechanics 2004; 2: 20-8).

14.
Tree Physiol ; 23(12): 805-14, 2003 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12865246

RESUMO

This paper investigates the possible contribution of Short Rotation Cultures (SRC) to carbon sequestration in both current and elevated atmospheric CO2 concentrations ([CO2]). A dense poplar plantation (1 x 1 m) was exposed to a [CO2] of 550 ppm in Central Italy using the free-air CO2 enrichment (FACE) technique. Three species of Populus were examined, namely P. alba L., P. nigra L. and P. x euramericana Dode (Guinier). Aboveground woody biomass of trees exposed to elevated [CO2] for three growing seasons increased by 15 to 27%, depending on species. As a result, light-use efficiency increased. Aboveground biomass allocation was unaffected, and belowground biomass also increased under elevated [CO2] conditions, by 22 to 38%. Populus nigra, with total biomass equal to 62.02 and 72.03 Mg ha-1 in ambient and elevated [CO2], respectively, was the most productive species, although its productivity was stimulated least by atmospheric CO2 enrichment. There was greater depletion of inorganic nitrogen from the soil after three growing seasons in elevated [CO2], but no effect of [CO2] on stem wood density, which differed significantly only among species.


Assuntos
Dióxido de Carbono/fisiologia , Populus/crescimento & desenvolvimento , Árvores/crescimento & desenvolvimento , Biomassa , Fotossíntese/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Brotos de Planta/crescimento & desenvolvimento
15.
Environ Pollut ; 120(2): 455-61, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12395859

RESUMO

The accumulation of Hg, Zn, and Cu was evaluated in mangrove sediments located between a large, 20-years-old landfill and waters of Guanabara Bay (southeast Brazil). The contamination history of the area provides substantial evidence that metal accumulation in the study site is influenced by past metal emissions from multiple sources (e.g. contaminated rivers and the landfill surrounding the site). At the southern part of the site, metal levels are up to 890 ng g(-1) Hg, 850 microg g(-1) Zn, and 58 microg g(-1) Cu. Enrichment factors and excess (background-deducted) concentration inventories show a high spatial variability of metal contamination and storage in the site, with differences often by a factor higher than two within a sampling station and higher than five between sampling stations. These contrasts are attributable to a coupling between spatial variability of anthropogenic metal input and metal behavior and retention within the sediments. Results indicate that during the last few decades mangrove sediments retained a substantial part of metal emissions to the site, probably reducing the metal transport to Guanabara Bay waters, and suggest the suitability of mangrove ecosystems as physical and biogeochemical barriers to metal contaminant transport.


Assuntos
Poluição Ambiental , Resíduos Perigosos , Metais/análise , Gerenciamento de Resíduos/métodos , Brasil , Cobre/análise , Sedimentos Geológicos , Mercúrio/análise , Fatores de Tempo , Zinco/análise
16.
Exp Cell Res ; 272(2): 119-26, 2002 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-11777336

RESUMO

Intrathymic maturation of thymocytes is essential for the proper formation of T-cell repertoire. This process involves two major biochemical pathways, one initiated by the recognition of MHC/peptide by the T-cell receptor and the other mediated by glucocorticoids. These hormones seem to affect thymocyte maturation by increasing the threshold of TCR-mediated positive and negative selection, and by inducing apoptosis of nonselected thymocytes. We have previously reported that an SV40-immortalized murine thymic epithelial cell line, namely 2BH4, was able to protect thymocytes from dexamethasone-induced apoptosis. Here we show that this protection is independent of cell-to-cell contact and does not seem to involve a Bcl-2-mediated resistance, since incubation of thymocytes with 2BH4 cells or its supernatant does not interfere with the levels of this antiapoptotic molecule. The protection conferred by 2BH4 cells, or by a primary culture of thymic stromal cells, is specific for the CD4(+)CD8(-) and CD4(-)CD8(+) single-positive thymocytes, whereas the broad-spectrum caspase inhibitor z-VAD-fmk blocks apoptosis induced by dexamethasone in all thymocyte subpopulations. Our results suggest that positively selected single-positive thymocytes are still susceptible to glucocorticoid-induced apoptosis but are protected from it through the action of a heat-stable protein(s) released by thymic stromal cells.


Assuntos
Apoptose , Linfócitos T CD4-Positivos/efeitos dos fármacos , Linfócitos T CD8-Positivos/efeitos dos fármacos , Dexametasona/farmacologia , Glucocorticoides/farmacologia , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Timo/citologia , Animais , Linfócitos T CD4-Positivos/citologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD8-Positivos/citologia , Linfócitos T CD8-Positivos/metabolismo , Resistência a Medicamentos , Células Epiteliais/citologia , Células Epiteliais/efeitos dos fármacos , Células Epiteliais/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Regulação para Cima
17.
J Biomed Mater Res ; 50(3): 381-7, 2000 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-10737880

RESUMO

It is well known that osteolysis induced by polyethylene wear debris is the main cause of long-term failure of hip and knee prostheses. We developed a treatment of medical-grade ultra-high molecular-weight polyethylene (UHMWPE) in order to improve its tribologic properties and reduce its wear. Medical-grade UHMWPE was irradiated with a 200 kGy dose of radiation, thermally stabilized at a temperature close to the melting point, and then sterilized with ethylene oxide. The irradiation treatment was performed to crosslink the UHMWPE. The thermal stabilization treatment, contributing to the reaction between the free radicals generated by the irradiation process, was chosen to enhance crosslinking and to prevent oxidation and the shortening of chains. The non-invasive sterilization process with ethylene oxide was chosen to prevent the re-formation of free radicals. The wear performance of this material was compared to UHMWPE, untreated or treated with different sterilization techniques, using gamma and beta irradiation. Insoluble crosslinked constituents were measured with an extraction method. Wear was evaluated using a flat-on-ring wear test machine. While small differences were found among the different sterilization processes, 200 kGy-irradiated UHMWPE followed by thermal treatment and sterilization with ethylene oxide had the least wear and the greatest amount of crosslinking.


Assuntos
Materiais Biocompatíveis , Prótese Articular , Polietilenos , Reagentes de Ligações Cruzadas , Humanos , Propriedades de Superfície
18.
Eur J Epidemiol ; 15(1): 11-4, 1999 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-10098990

RESUMO

A seroprevalence survey of antibodies to HCV was carried out among 2788 hemodialysis (HD) patients in a region of central Italy. Anti-HCV seroprevalence was 28.6%. A multivariate analysis of risk factors showed a significant association with time on HD, history of blood transfusion and metropolitan area of residence. Our study clearly showed that HCV infection is common among HD patients and is partially associated with preventable factors.


Assuntos
Hepatite C/epidemiologia , Diálise Renal , Adolescente , Adulto , Idoso , Anticorpos Antivirais/análise , Feminino , Hepacivirus/imunologia , Humanos , Itália/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Sistema de Registros , Fatores de Risco , Estudos Soroepidemiológicos
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