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41.
Anabel Pérez-Gómez Armando García-Rodríguez Kevin J James Amaia Ferrero-Gutierrez Antonello Novelli M Teresa Fernández-Sánchez 《Toxicological sciences》2004,80(1):74-82
Diarrhetic shellfish poisoning (DSP) toxins of algal origin are frequent contaminants of coastal waters and seafood. The potential risk for human health due to the continuous presence of these toxins in food has not been clearly established. We have used cerebellar primary cultures to investigate the effects of the DSP toxin dinophysistoxin-2 (DTX-2) on central nervous system neurons and glial cells. Exposure to DTX-2 produced neurotoxicity at concentrations starting at 2.5 nM, characterized first by disintegration of neurites and later by cell death. DTX-2-induced neurodegeneration required long exposures (at least 20 h), involved DNA fragmentation and condensation and fragmentation of chromatin, typical hallmarks of apoptosis, and required the synthesis of new proteins. The concentration that reduced by 50% the maximum neuronal survival after 24 h exposure to DTX-2 (EC50(24)) was approximately 8 nM. Morphology and viability of glial cells remained unaffected up to at least 15 nM DTX-2. Higher concentrations of the toxin caused strong shrinkage of glial cell bodies and retraction of processes, and a significant reduction of glial cell viability. Glial toxicity by DTX-2 involved typical apoptotic condensation and fragmentation of chromatin. Compared to neurons, the effect on glial cells was a much shorter process, and extensive glial degeneration and death occurred after 7 h exposure to DTX-2 (EC50(7) approximately 50 nM; EC50(24) approximately 30 nM). Although further experiments are needed to confirm these toxic actions in vivo, our in vitro data suggest that chronic exposure to amounts of DSP toxins below the current safety regulatory limits may represent a risk for human health that should be taken into consideration. 相似文献
42.
Armando Pérez-Rangel José Manuel Hernández Araceli Castillo-Romero Lilián Yépez-Mulia Rafael Castillo Francisco Hernández-Luis Benjamín Nogueda-Torres Juan Pedro Luna-Arias Gerardo Radilla Gloria León-Avila 《Parasitology research》2013,112(9):3251-3257
In the present study, we evaluated the effect of an albendazole (ABZ) derivative JVG9 on cultured Giardia intestinalis. To assess the JVG9 effects, we evaluated the tubulin cytoskeleton by confocal microscopy, and we found that the characteristic staining was modified. The scanning electron microscopy images revealed extremely damaged trophozoites and cyst-like cells. The confocal images revealed that this drug triggered the expression of cyst wall protein 1 and encystation. We also found that at low doses, AL triggered the encystation process too. 相似文献
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44.
Erica de Camargo Ferreira e Vasconcellos Maria Inês Fernandes Pimentel Cláudia Maria Valete-Rosalino Maria de Fátima Madeira Armando de Oliveira Schubach 《Revista do Instituto de Medicina Tropical de S?o Paulo》2014,56(4):361-362
We report a case of a 42 year-old female, who came to a leishmaniasis
reference center in Rio de Janeiro, Brazil, presenting a cutaneous leishmaniasis
lesion in the right forearm. Treatment with low-dose intramuscular meglumine
antimoniate (MA) (5 mg Sb5+/kg/day) was initiated, with improvement after
28 days, although with the development of generalized eczema. After 87 days, the
lesion worsened. Patient refused treatment with amphotericin B. MA was then
infiltrated in the lesion, in two sessions, resulting in local eczema, with bullae
formation; however, twenty days after, both the ulcer and eczema receded.
Intralesional administration of MA should be used carefully when previous cutaneous
hypersensitivity is detected. 相似文献
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José M. de la Torre Hernández Salvatore Brugaletta Joan A. Gómez Hospital José A. Baz Armando Pérez de Prado Ramón López Palop Belen Cid Tamara García Camarero Alejandro Diego Hipólito Gutiérrez José A. Fernández Diaz Juan Sanchis Fernando Alfonso Roberto Blanco Javier Botas Javier Navarro Cuartero José Moreu Francisco Bosa Antonio J. Domínguez 《Revista espa?ola de cardiología》2019,72(12):1005-1011
Background and objectivesPatients older than 75 years with ST-segment elevation myocardial infarction undergoing primary angioplasty in cardiogenic shock have high mortality. Identification of preprocedural predictors of short- and long-term mortality could be useful to guide decision-making and further interventions.MethodsWe analyzed a nationwide registry of primary angioplasty in the elderly (ESTROFA MI + 75) comprising 3576 patients. The characteristics and outcomes of the subgroup of patients in cardiogenic shock were analyzed to identify associated factors and prognostic predictors in order to derive a baseline risk prediction score for 1-year mortality. The score was validated in an independent cohort.ResultsA total of 332 patients were included. Baseline independent predictors of mortality were anterior myocardial infarction (HR 2.8, 95%CI, 1.4-6.0; P = .005), ejection fraction < 40% (HR 2.3, 95%CI, 1.14-4.50; P = .018), and time from symptom onset to angioplasty > 6 hours (HR 3.2, 95%CI, 1.6-7.5; P = .001). A score was designed that included these predictive factors (score “6-ANT-40”). Survival at 1 year was 54.5% for patients with score 0, 32.3% for score 1, 27.4% for score 2 and 17% for score 3 (P = .004, c-statistic 0.70). The score was validated in an independent cohort of 124 patients, showing 1-year survival rates of 64.5%, 40.0%, 28.9%, and 22.2%, respectively (P = .008, c-statistic 0.68).ConclusionsA preprocedural score based on 3 simple clinical variables (anterior location, ejection fraction < 40%, and delay time > 6 hours) may be used to estimate survival after primary angioplasty in elderly patients with cardiogenic shock and to guide preinterventional decision-making. 相似文献
48.
Massimo Fusconi Michela Conte Martina Pagliarella Chiara De Vincentiis Armando De Virgilio Anna Teresa Benincasa Simone Alessi Andrea Gallo 《Skull base》2013,74(6):364-368
Objective Fibrous dysplasia (FD) is a benign bone disorder in facial bones. This study evaluates the possibility of diagnosing fibrous dysplasia on imaging alone, without biopsy of the lesion, which is often burdensome for the patient.
Materials and Methods The authors bring their experience of four cases of bone lesions of the maxillofacial region and present a review of published studies. The imaging techniques evaluated are computed tomography (CT) and magnetic resonance imaging (MRI) with and without contrast.
Results The literature review demonstrates that it is impossible to make diagnosis of fibrous dysplasia exclusively by imaging. Radiographic images often show a ground-glass appearance, which is characteristic but not pathognomonic of fibrous dysplasia.
Conclusion Although CT and MRI images may in many cases suggest a diagnosis of fibrous dysplasia, histological examination or follow-up imaging should follow. 相似文献
49.
ABSTRACT This study, using data collected as part of an ongoing programme evaluation, investigates whether participation in Saving Groups (SGs)—a community-owned microfinance intervention focused on poor households – is associated with maternal health service utilisation, and whether this association is mediated by women’s agency – as measured by self-efficacy and decision-making autonomy. We compared maternal health service utilisation among SG members (n=105) and non-members (n=100) in rural Mozambique. We estimated prevalence ratios for SG membership and women’s agency using Poisson regression while controlling for confounding factors. We also estimated mediation effects for women's agency. The results showed that SG membership is associated with four or more antenatal care (ANC) visits, skilled birth attendant (SBA) use, and postnatal care within 48?h of delivery. Self-efficacy mediated the relationship between SG membership and ANC vists and SBAuse, but not postnatal care; whereas women’s decision-making autonomy mediated the relationship with SBA use and postnatal care, but not ANC visits. This study suggests that the impact of SG membership on use of maternal health services goes beyond improvements in household income and may operate through women’s agency by giving women the ability to realize their preference for quality health care. 相似文献
50.
Armando Perrotta MD PhD Natalia Arce‐Leal MD PhD Cristina Tassorelli MD PhD Valeria Gasperi PhD Grazia Sances MD Fabio Blandini MD PhD Mariano Serrao MD PhD Monica Bolla MD Francesco Pierelli MD DrMSc Giuseppe Nappi MD DrMSc Mauro Maccarrone DrMSc Giorgio Sandrini MD DrMSc 《Headache》2012,52(9):1350-1361
Objectives.— We investigated (1) a possible relationship between the functional activity of the endocannabinoid system and the facilitation of pain processing in migraineurs with medication‐overuse headache, and (2) the effect of withdrawal treatment on both. Background.— The endocannabinoid system antinociception effect includes prevention of nociceptive pathways sensitization. The sensitization of the pain pathways has been demonstrated to be pivotal in the development and maintenance of chronic form of migraine, including medication‐overuse headache. Methods.— We used the temporal summation threshold of the nociceptive withdrawal reflex to explore the spinal cord pain processing, and the platelet activity of the enzyme fatty acid amide hydrolase to detect the functional state of the endocannabinoid system in 27 medication‐overuse headache subjects before and 10 and 60 days after a standard withdrawal treatment and compared results with those of 14 controls. Results.— A significantly reduced temporal summation threshold and increased related pain sensation was found in subjects before withdrawal treatment when compared with controls. A significant fatty acid amide hydrolase activity reduction coupled with a significant improvement (reduction) in facilitation of spinal cord pain processing (increase in temporal summation threshold and reduction in related pain sensation) was found in medication‐overuse headache subjects at both 10 and 60 days after withdrawal treatment when compared with medication‐overuse headache subjects before withdrawal treatment. Conclusions.— We demonstrated a marked facilitation in spinal cord pain processing in medication‐overuse headache before withdrawal treatment when compared with controls. Furthermore, the acute reduction of the fatty acid amide hydrolase activity coupled with a reduction of the facilitation in pain processing immediately (10 days) after withdrawal treatment and its persistence 60 days after withdrawal treatment could represent the consequence of a mechanism devoted to acutely reduce the degradation of endocannabinoids and aimed to increase the activity of the endocannabinoid system that results in an antinociceptive effect. 相似文献