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1.
Phys Rev Lett ; 132(21): 215001, 2024 May 24.
Artículo en Inglés | MEDLINE | ID: mdl-38856283

RESUMEN

We present a new approach that demonstrates the deflection and guiding of relativistic electron beams over curved paths by means of the magnetic field generated in a plasma-discharge capillary. We experimentally prove that the guiding is much less affected by the beam chromatic dispersion with respect to a conventional bending magnet and, with the support of numerical simulations, we show that it can even be made dispersionless by employing larger discharge currents. This proof-of-principle experiment extends the use of plasma-based devices, that revolutionized the field of particle accelerators enabling the generation of GeV beams in few centimeters. Compared to state-of-the-art technology based on conventional bending magnets and quadrupole lenses, these results provide a compact and affordable solution for the development of next-generation tabletop facilities.

2.
Phys Rev E ; 109(5-2): 055202, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38907494

RESUMEN

Plasma wakefield acceleration represented a breakthrough in the field of particle accelerators by pushing beams to gigaelectronvolt energies within centimeter distances. The large electric fields excited by a driver pulse in the plasma can efficiently accelerate a trailing witness bunch paving the way toward the realization of laboratory-scale applications like free-electron lasers. However, while the accelerator size is tremendously reduced, upstream and downstream of it the beams are still handled with conventional magnetic optics with sizable footprints and rather long focal lengths. Here we show the operation of a compact device that integrates two active-plasma lenses with short focal lengths to assist the plasma accelerator stage. We demonstrate the focusing and energy gain of a witness bunch whose phase space is completely characterized in terms of energy and emittance. These results represent an important step toward the accelerator miniaturization and the development of next-generation table-top machines.

3.
Neth Heart J ; 29(3): 121-128, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33415605

RESUMEN

BACKGROUND: Many patients with angina do not have obstructive coronary artery disease (CAD), also referred to as "Ischaemia with No Obstructive Coronary Arteries" (INOCA). Coronary vascular dysfunction is the underlying cause of this ischaemic heart disease in as much as 59-89% of these patients, including the endotypes of coronary microvascular dysfunction and epicardial coronary vasospasm. Currently, a coronary function test (CFT) is the only comprehensive diagnostic modality to evaluate all endotypes of coronary vascular dysfunction in patients with INOCA. OBJECTIVE: In this paper we discuss the relevance of performing a CFT, provide considerations for patient selection, and present an overview of the procedure and its safety. METHODS: We reviewed the latest published data, guidelines and consensus documents, combined with a discussion of novel original data, to present this point of view. RESULTS: The use of a CFT could lead to a more accurate and timely diagnosis of vascular dysfunction, identifies patients at risk for cardiovascular events, and enables stratified treatment which improves symptoms and quality of life. Current guidelines recommend considering a CFT in patients with INOCA and persistent symptoms. The safety of the procedure is comparable to that of a regular coronary angiography with physiological measurements. Non-invasive alternatives have limited diagnostic accuracy for the identification of coronary vascular dysfunction in patients with INOCA, and a regular coronary angiography and/or coronary computed tomography scan cannot establish the diagnosis. CONCLUSIONS: A complete CFT, including acetylcholine and adenosine tests, should be considered in patients with INOCA.

4.
Mar Environ Res ; 156: 104901, 2020 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-32056796

RESUMEN

Microalgae are considered good bioindicators of marine environmental quality. Frequently, they are used to investigate the toxicity of sediment elutriates, but their sensitivity is disputed. This paper compared the sensitivity of Phaeodactylum tricornutum (diatom), Skeletonema costatum (diatom), and Dunaliella tertiolecta (green alga), analyzing 257 samples of elutriates (1:4 sediment: water ratio), considering growth inhibition (72 h) as the reference endpoint and sediment chemical (metals, metalloids and polyaromatic hydrocarbons) and grain size. Results of the toxicity tests showed that the microalgae sensitivity was not correlated. The integration of chemical data did not allow to discriminate toxicity effects but contributed to highlight that D. tertiolecta was the most sensitive microalgae (no cell wall) followed by P. tricornutum and S. costatum. Further analysis, including lines of evidence and weight of evidence approaches to calculate risk quotients of elutriate samples, confirmed these results.


Asunto(s)
Diatomeas/efectos de los fármacos , Microalgas/efectos de los fármacos , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Metaloides/toxicidad , Metales/toxicidad , Hidrocarburos Policíclicos Aromáticos/toxicidad , Especificidad de la Especie , Pruebas de Toxicidad
5.
Phys Rev Lett ; 121(17): 174801, 2018 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-30411933

RESUMEN

Plasma-based technology promises a tremendous reduction in size of accelerators used for research, medical, and industrial applications, making it possible to develop tabletop machines accessible for a broader scientific community. By overcoming current limits of conventional accelerators and pushing particles to larger and larger energies, the availability of strong and tunable focusing optics is mandatory also because plasma-accelerated beams usually have large angular divergences. In this regard, active-plasma lenses represent a compact and affordable tool to generate radially symmetric magnetic fields several orders of magnitude larger than conventional quadrupoles and solenoids. However, it has been recently proved that the focusing can be highly nonlinear and induce a dramatic emittance growth. Here, we present experimental results showing how these nonlinearities can be minimized and lensing improved. These achievements represent a major breakthrough toward the miniaturization of next-generation focusing devices.

6.
Ecotoxicol Environ Saf ; 154: 237-244, 2018 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-29476973

RESUMEN

The use of engineered nanomaterials (ENMs) for environmental remediation, known as nanoremediation, represents a challenging and innovative solution, ensuring a quick and efficient removal of pollutants from contaminated sites. Although the growing interest in nanotechnological solutions for pollution remediation, with significant economic investment worldwide, environmental and human risk assessment associated with the use of ENMs is still a matter of debate and nanoremediation is seen yet as an emerging technology. Innovative nanotechnologies applied to water and soil remediation suffer for a proper environmental impact scenario which is limiting the development of specific regulatory measures and the exploitation at European level. The present paper summarizes the findings from the workshop: "Ecofriendly Nanotechnology: state of the art, future perspectives and ecotoxicological evaluation of nanoremediation applied to contaminated sediments and soils" convened during the Biannual ECOtoxicology Meeting 2016 (BECOME) held in Livorno (Italy). Several topics have been discussed and, starting from current state of the art of nanoremediation, which represents a breakthrough in pollution control, the following recommendations have been proposed: (i) ecosafety has to be a priority feature of ENMs intended for nanoremediation; ii) predictive safety assessment of ENMs for environmental remediation is mandatory; (iii) greener, sustainable and innovative nano-structured materials should be further supported; (iii) those ENMs that meet the highest standards of environmental safety will support industrial competitiveness, innovation and sustainability. The workshop aims to favour environmental safety and industrial competitiveness by providing tools and modus operandi for the valorization of public and private investments.


Asunto(s)
Restauración y Remediación Ambiental , Nanoestructuras , Nanotecnología , Consenso , Ecotoxicología , Contaminación Ambiental , Contaminantes del Suelo , Contaminación del Agua
7.
J Food Prot ; 80(10): 1605-1612, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28853626

RESUMEN

International food transit is a risk to public and animal health when not subject to legal importation sanitation procedures. Due to the extensive border area, illegal food import in Brazil is a common practice, especially in Rio Grande do Sul (RS), a state that borders with Argentina and Uruguay. The objective of this study was to evaluate the profile of Brazilians living in cities in RS that border with Argentina (BR-AR) or Uruguay (BR-UR) regarding the practice of illegal import of products of animal origin and to determine associations between the population characteristics and illegal import. A questionnaire with information related to the personal profile, habits of acquisition of imported food, and knowledge of health risks deriving from the consumption of the imported products was elaborated. The questionnaire was administered in six cities in RS (three cities bordering Argentina and three cities bordering Uruguay) and responses were obtained from 744 individuals. The variables city, sex, level of education, and knowledge were subjected to the chi-square test to verify the association between these variables and food import. Part of the interviewees admitted to illegally importing products of animal origin at both BR-AR (65.17%) and BR-UR (76.28%) borders. Dairy products were the main imported goods, followed by raw and processed meat. The study revealed that illegal import is common at the frontier region of RS, especially that of products of animal origin, dairy, and raw and processed meat. Although illegal importation occurs at all the cities under study, it was higher at the BR-UR border. Also, knowledge of the health risks influences the decision to import food or not.


Asunto(s)
Comercio/legislación & jurisprudencia , Carne , Animales , Argentina , Brasil , Ciudades , Humanos , Uruguay
8.
Sci Rep ; 7(1): 603, 2017 04 04.
Artículo en Inglés | MEDLINE | ID: mdl-28377615

RESUMEN

MALDI mass spectrometry imaging is able to simultaneously determine the spatial distribution of hundreds of molecules directly from tissue sections, without labeling and without prior knowledge. Ultra-high mass resolution measurements based on Fourier-transform mass spectrometry have been utilized to resolve isobaric lipids, metabolites and tryptic peptides. Here we demonstrate the potential of 15T MALDI-FTICR MSI for molecular pathology in a mouse model of high-grade glioma. The high mass accuracy and resolving power of high field FTICR MSI enabled tumor specific proteoforms, and tumor-specific proteins with overlapping and isobaric isotopic distributions to be clearly resolved. The protein ions detected by MALDI MSI were assigned to proteins identified by region-specific microproteomics (0.8 mm2 regions isolated using laser capture microdissection) on the basis of exact mass and isotopic distribution. These label free quantitative experiments also confirmed the protein expression changes observed by MALDI MSI and revealed changes in key metabolic proteins, which were supported by in-situ metabolite MALDI MSI.


Asunto(s)
Glioblastoma/metabolismo , Metaboloma , Metabolómica , Proteoma , Proteómica , Animales , Cromatografía Liquida , Metabolismo Energético , Redes y Vías Metabólicas , Metabolómica/métodos , Ratones , Proteómica/métodos , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Espectrometría de Masas en Tándem
9.
Gynecol Oncol ; 143(2): 276-280, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27597380

RESUMEN

OBJECTIVE: Evidence-based management of granulosa cell tumors of the ovary (GCT) has been not yet standardized: surgery, including fertility-sparing procedures for young women, has been traditionally the standard treatment; on the other hand, chemotherapy has been used for treatment of advanced and/or recurrent disease. However, very limited experience, has been selectively focused on the role of adjuvant chemotherapy in stage IC patients. The objective of this retrospective study was to assess the efficacy of first line postoperative chemotherapy in patients with stage IC treated at the Italian Centers involved in the MITO (Multicenter Italian Trials in Ovarian cancer) Group. PATIENTS AND METHODS: A retrospective multi-institutional review of patients with GCT of the ovary at FIGO stage IC treated or referred to MITO centers was conducted. Surgical outcome, pathological findings and follow-up data were analysed. Kaplan-Meier and Cox proportional hazards analyses were used to determine the predictors factors for disease free survival. RESULTS: A total of 40 patients with primary GCT of the ovary at FIGO stage IC were identified. The median follow-up period was 96months (range 7-300). At multivariate analysis, surgical treatment outside MITO centers and incomplete surgical staging were independent poor prognostic indicators for recurrence; adjuvant chemotherapy did not retain significant predictive value for recurrence. CONCLUSIONS: This study raises the question about the value of adjuvant chemotherapy in stage IC GCT: a comprehensive evaluation of a larger series is urgently needed in order to characterize stage IC substages who can be spared treatment toxicity.


Asunto(s)
Tumor de Células de la Granulosa/tratamiento farmacológico , Adulto , Anciano , Quimioterapia Adyuvante , Supervivencia sin Enfermedad , Femenino , Tumor de Células de la Granulosa/mortalidad , Tumor de Células de la Granulosa/patología , Humanos , Persona de Mediana Edad , Estadificación de Neoplasias , Estudios Retrospectivos
10.
Ecotoxicology ; 25(5): 1033-9, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27106013

RESUMEN

The calanoid copepod Acartia tonsa has been recommended as a marine organism for ecotoxicological tests due to its wide distribution, short life cycle and high productivity. This species is used in acute and chronic toxicity tests to assess water and sediment quality; egg hatching success and the survival of the first larval stages are considered endpoints. Toxicity test protocols require a large number of organisms and an appropriate culture system. Eggs stored under conditions that delay hatching could ensure sufficient quantities of biological materials for ecotoxicological tests. In the current study early-spawned eggs were stored at 3 °C (±1) up to 240 days and their hatching success was evaluated on a monthly basis. Our results showed that the percentage of hatching success for eggs stored for 30 days was >80 % and decreased by about 8 % for every 20 days of storage, up to 120 days. A further increase of time in cold storage brought about a significant reduction, in statistical term, of hatching success compared with the control group (43.69 ± 22.19 %). Almost 50 % of eggs hatched or died during the cold storage period, with more than 80 % lost after periods longer than 150 days. To verify the suitability of stored eggs for toxicity test, 48 h acute tests were performed using nickel chloride as a referent toxicant. Eggs stored for 30, 60, 90 and 120 days gave EC50 values ranging from 0.130 to 0.221 mg L(-1), similar to the value recorded for early-spawned eggs, suggesting that these eggs can be used for ecotoxicological tests. Our results open new possibilities for a wider use of the Mediterranean strain of A. tonsa copepod for ecotoxicological tests.


Asunto(s)
Copépodos/fisiología , Monitoreo del Ambiente/métodos , Pruebas de Toxicidad Aguda/métodos , Contaminantes Químicos del Agua/toxicidad , Animales , Organismos Acuáticos , Ecotoxicología , Monitoreo del Ambiente/normas , Larva , Óvulo , Pruebas de Toxicidad Aguda/normas
11.
Ecotoxicol Environ Saf ; 123: 2-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26477574

RESUMEN

The sea urchin embryo toxicity test is classically used to assess the noxious effects of contaminated marine waters and sediments. In Italian guidelines on quality of dredged sediments, the standard toxicity criteria used for this assay are based on a single endpoint at 48 hours of development, corresponding to the pluteus stage. Different typologies of abnormalities, including those which occur at earlier stages, are not categorized, thus preventing the evaluation of the actual teratogenic hazards. A new integrative toxicity index has been developed in this study based on the analysis of two developmental stages, at 24 and 48h post-fertilization, and the differentiation between development delays and germ layers impairments: the new toxicity index is calculated by integrating the frequency of abnormal embryos with the severity of such abnormalities. When tested on dredged sediments, the evaluation of increasing levels of toxicity affecting embryonic outcomes enhanced the capability to discriminate different samples, appearing particularly relevant to validate the sea urchin embryo toxicity assay, and supporting its utility in practical applications such as the sediments classification in harbor areas.


Asunto(s)
Embrión no Mamífero/efectos de los fármacos , Erizos de Mar/efectos de los fármacos , Erizos de Mar/embriología , Teratógenos/toxicidad , Pruebas de Toxicidad/métodos , Animales , Bioensayo , Monitoreo del Ambiente , Fertilización/efectos de los fármacos , Sedimentos Geológicos/química
12.
Aquat Toxicol ; 170: 1-12, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26562184

RESUMEN

Nickel compounds are widely used in industries and have been massively introduced in the environment in different chemical forms. Here we report the effect of two different chemical forms of nickel, NiCl2 and nickel nanoparticles (NiNPs), on the reproduction of the marine calanoid copepod Acartia tonsa. The behavior of nickel nanoparticles was analyzed with different techniques and with two protocols. In the "sonicated experiment" (SON) NiNP solution was sonicated while in the "non-sonicated experiment" (NON-SON) the solution was vigorously shaken by hand. Final nominal concentrations of 5, 10 and 50mgL(-1) and 1, 5 and 10mgL(-1) NiNPs were used for the acute and semichronic tests, respectively. Nanoparticle size did not change over time except for the highest concentration of 50mgL(-1) NiNPs, in which the diameter increased up to 843nm after 48h. The concentration of Ni dissolved in the water increased with NP concentration and was similar for SON and NON-SON solutions. Our results indicate that sonication does not modify toxicity for the copepod A. tonsa. Mean EC50 values were similar for NON-SON (20.2mgL(-1)) and SON experiments (22.14mgL(-1)) in the acute test. Similarly, no differences occurred between the two different protocols in the semichronic test, with an EC50 of 7.45mgL(-1) and 6.97mgL(-1) for NON-SON and SON experiments, respectively. Acute and semichronic tests, conducted exposing A. tonsa embryos to NiCl2 concentrations from 0.025 to 0.63mgL(-1), showed EC50 of 0.164 and 0.039mgL(-1), respectively. Overall, A. tonsa is more sensitive to NiCl2 than NiNPs with EC50 being one order of magnitude higher for NiNPs. Finally, we exposed adult copepods for 4 days to NiCl2 and NiNPs (chronic exposure) to study the effect on fecundity in terms of daily egg production and naupliar viability. Egg production is not affected by either form of nickel, whereas egg viability is significantly reduced by 0.025mgL(-1) NiCl2 and by 8.5mgL(-1) NiNPs. At NiNP concentration below the acute EC50 (17mgL(-1)) only 9% of embryos hatched after 4 days. Interestingly, the percentage of naupliar mortality (>82%) observed in the semichronic test at the nominal concentration of 10mgL(-1) NiNPs corresponding to almost 0.10mgL(-1) of dissolved Ni, was similar to that recorded at the same Ni salt concentration. Electron microscopical analyses revealed that A. tonsa adults ingest NiNPs and excrete them through fecal pellets. To the best of our knowledge, this is the first study investigating the toxicity of two different forms of Ni on the reproductive physiology of the copepod A. tonsa and showing the ability of the calanoid copepod to ingest nanoparticles from seawater.


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Copépodos/efectos de los fármacos , Nanopartículas/toxicidad , Níquel/toxicidad , Contaminantes Químicos del Agua/toxicidad , Animales , Bioensayo , Femenino , Nanopartículas/ultraestructura , Tamaño de la Partícula , Espectrofotometría Atómica , Electricidad Estática , Pruebas de Toxicidad Aguda , Pruebas de Toxicidad Crónica
13.
Transbound Emerg Dis ; 59(2): 106-16, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21787379

RESUMEN

Risks of the introduction of highly pathogenic avian influenza (HPAI) H5N1 through migratory birds to the main wintering site for wild birds in southern Brazil and its consequences were assessed. Likelihoods were estimated by a qualitative scale ranging from negligible to high. Northern migrants that breed in Alaska and regularly migrate to South America (primary Charadriiformes) can have contact with birds from affected areas in Asia. The likelihood of the introduction of HPAI H5N1 through migratory birds was found to be very low as it is a probability conditioned to successful transmission in breeding areas and the probabilities of an infected bird migrating and shedding the virus as far as southern Brazil. The probability of wild species becoming exposed to H5N1-infected birds is high as they nest with northern migrants from Alaska, whereas for backyard poultry it is moderate to high depending on proximity to wetlands and the presence of species that could increase the likelihood of contact with wild birds such as domestic duck. The magnitude of the biological and economic consequences of successful transmission to poultry or wild birds would be low to severe depending on the probability of the occurrence of outbreak scenarios described. As a result, the risk estimate is greater than negligible, and HPAI H5N1 prevention strategy in the region should always be carefully considered by the veterinary services in Brazil.


Asunto(s)
Subtipo H5N1 del Virus de la Influenza A/patogenicidad , Gripe Aviar/virología , Migración Animal , Animales , Animales Salvajes , Aves , Brasil , Simulación por Computador , Salud Global , Gripe Aviar/epidemiología , Gripe Aviar/prevención & control , Gripe Aviar/transmisión , Modelos Biológicos , Medición de Riesgo
14.
Arq. Inst. Biol. (Online) ; 77(3): 381-387, jul.-set. 2010. tab, graf
Artículo en Portugués | VETINDEX, LILACS | ID: biblio-1391284

RESUMEN

A leptospirose é uma das principais enfermidades responsáveis pela baixa produtividade nos sistemas pecuários bovinos, sendo associada à redução na produção de leite, infertilidade, aborto, natimortalidade, além de aumento nos custos com despesas de assistência veterinária, vacinas e testes laboratoriais. Este estudo teve como objetivo analisar dados laboratoriais de sorologia para leptospirose bovina no Estado do Rio Grande do Sul, durante um período de 1996 a 2006, visando detectar tendências na frequência de reagentes e gerar hipóteses sobre a variação da frequência de soropositivos ao longo deste período. Análises de regressão linear e modelo linear generalizado foram realizadas para detectar tendências e verificar fatores que influenciam na frequência de soropositivos, respectivamente. Durante o período de 11 anos, foram analisadas 18.806 amostras de soro, sendo que 9.385 resultaram positivas (49,9%). A análise da série temporal por sorovar revelou uma tendência linear crescente estatisticamente significativa na frequência dos seguintes sorovares: Australis, Autumnalis, Bratislava, Copenhageni, Grippotyphosa, Pyrogenes e Tarassovi (p < 0,01). Por outro lado, foi observada uma tendência decrescente estatisticamente significativa na frequência dos sorovares Hardjo e Wolffi (p < 0,01) ao longo do período avaliado. Houve uma associação estatisticamente significativa entre índices pluviométricos (mm) e o número de soropositivos para Leptospira spp. (p = 0,01, OR = 1,003).


Leptospirosis is an infectious disease that causes losses of productivity in cattle due to reduction of milk production, reproductive disorders and calf mortality, while also increasing costs associated with veterinary care, vaccines and diagnostic tests. The objective of this study was to analyze serological findings for bovine leptospirosis in the State of Rio Grande do Sul, Brazil, in order to detect temporal trends in the frequency of seropositive animals and to generate hypothesis about the fluctuation in seroprevalence along the period from 1996 to 2006. Simple linear regression and generalized linear models were used to analyze trends and verify factors influencing the frequency of seropositive animals, respectively. During 11 years, 18,806 serum samples were analyzed, in which 9,385 were positive (49.9%). The time-series analysis by serovars revealed a statistically significant increasing trend in the frequency of the following serovars: Australis, Autumnalis, Bratislava, Copenhageni, Grippotyphosa, Pyrogenes and Tarassovi (p < 0.01). Conversely, a statistically significant decreasing trend was observed for the serovars Hardjo and Wolffi (p < 0.01). There was a significant association between rain precipitation (mm) and the number of samples seropositive for leptospirosis (p = 0.01, OR = 1,003).


Asunto(s)
Animales , Bovinos , Leptospirosis/sangre , Leptospirosis/epidemiología , Brasil , Modelos Lineales , Estudios Seroepidemiológicos
16.
An Med Interna ; 25(2): 85-9, 2008 Feb.
Artículo en Español | MEDLINE | ID: mdl-18432366

RESUMEN

Ascites is rare in patients with multiple myeloma (MM). It may be due to diverse mechanisms, most frequently because of an increased permeability of the peritoneum or because of portal hypertension due to liver infiltration. Myelomatous ascites occurs more frequently in patients having Ig-G or Ig-A paraprotein and their prognosis is poor. It is submitted the case of a female patient aged 50 years with IgA-kappa MM, who evolved with cardiac failure (CF), plasma cells leukemia and ascites of mixed cause, because of peritoneal infiltrate of myelomatous cells, hepatic compromise and CF. A review of the different causes of ascites in patients with MM is performed. There are also summarized all myelomatous ascites cases published in the literature. Our report presents the first case of myelomatous ascites in a patient with plasma cells leukemia.


Asunto(s)
Ascitis/etiología , Mieloma Múltiple/complicaciones , Femenino , Humanos , Persona de Mediana Edad
17.
Environ Monit Assess ; 136(1-3): 121-7, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17394091

RESUMEN

The aim of this work was to monitor the sensitivity of two populations of Corophium orientale (Crustacea: Amphipoda) living at the outfall of two rivers (Magra and Serchio), comparing their responses towards two different toxicant solutions. Sensitivity was monthly checked performing the 96h-LC50 static water only test with Cd(NO3)2 and SDS. If no significant differences were found between the two populations, they could have been employed without distinction to perform sediment toxicity bioassays. As regard to Cd, an increasing in LC50 values from summer to winter was evident in each population (Serchio River: August 2003 = 1,36 mg/l, February 2004 = 7,23 mg/l; Magra River: August = 1,21 mg/l, April = 5,01 mg/l). This pattern was correlated to the droop of temperatures in winter period. The responses of the two populations towards the cadmium were compared using the ANOVA. The analysis showed any significant differences between the populations (p = 0.12). The pattern of sensitivity towards SDS for the population living on Magra River was similar to the same pattern found for Cd; as regard to the population living on Serchio River, data were not enough to describe the annual pattern. Anyway, statistical analysis was performed and no significant differences were found between the two populations (p = 0.34).


Asunto(s)
Anfípodos/efectos de los fármacos , Cadmio/farmacología , Agua Dulce , Dodecil Sulfato de Sodio/farmacología , Tensoactivos/farmacología , Contaminantes Químicos del Agua/farmacología , Anfípodos/metabolismo , Animales , Italia , Dosificación Letal Mediana , Contaminantes Químicos del Agua/análisis
18.
An Med Interna ; 23(7): 345-6, 2006 Jul.
Artículo en Español | MEDLINE | ID: mdl-17067237

RESUMEN

Einstein's sign is a syndrome similar to an acute cholecystitis caused by the rupture of an abdominal aortic aneurysm. In this paper we describe the evolution of the disease that the physicist suffered till it led him to death. We also revise other signs which could be found in some patients with ruptured or dissected abdominal aortic aneurysm.


Asunto(s)
Aneurisma de la Aorta/diagnóstico , Examen Físico , Humanos
19.
Environ Monit Assess ; 119(1-3): 1-13, 2006 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16767501

RESUMEN

Several experiments were performed to evaluate the fertilization capability of Paracentrotus lividus sea urchin gametes, which are usually used in fertilization tests, but which, until now, were employed only for few hours after spawning. The aim of this work is to evaluate the possibility of performing the bioassay for longer periods, employing 'conserved' gametes. As far as the method, the sperm was stored 'dry' at 4 degrees C; eggs were conserved in an antibiotic solution at 4 degrees C, and they were exposed both to copper solutions as reference toxicant and to aqueous matrices. The use of conserved gametes in the fertilization bioassay lead to EC50 values which were acceptable for about 3 days. Moreover, these experiments permitted to identify the limiting factor: the male gamete.


Asunto(s)
Fertilización/efectos de los fármacos , Células Germinativas/efectos de los fármacos , Contaminantes Químicos del Agua/toxicidad , Animales , Bioensayo/métodos , Frío , Cobre/toxicidad , Embrión no Mamífero/efectos de los fármacos , Femenino , Masculino , Erizos de Mar
20.
Environ Monit Assess ; 122(1-3): 101-9, 2006 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-16738765

RESUMEN

The sperm cell toxicity test with Paracentrotus lividus is widely used in Italy to assess the quality of complex aqueous matrices, but at present there is a shortage of standardized methodologies for the bioassay performance. In this work several critical points were considered, in order to verify the reliability of this bioassay and to improve its standardization. In particular, we have studied the differences in EC50 values at different sperm: egg ratios and with different quantities of gametes; the influence of sperm and eggs on fertilization rate and the influence of different recipients materials (plastic or glass). At the same time, it was evaluated if the obtained EC50 values were in accordance with those reported in literature. Experiments performed yielded EC50 values for copper ranging from 16.54 microg/l to 69.59 microg/l, with a total mean value +/- SD of 39.79 microg/l +/- 11.17. These data fit with those found in literature for other echinoid species. According to the same authors, poor fertilization was probably due to the effects on sperm and not on eggs, and moreover the linear regression analysis performed on each experiment suggested that the best amount of eggs to use in the test was 1000. Results from the comparison between the performance of the test in plastic or glass tubes showed an higher success in fertilization rate using borosilicate glass tubes.


Asunto(s)
Monitoreo del Ambiente/normas , Paracentrotus , Agua de Mar/análisis , Espermatozoides , Contaminantes del Agua/toxicidad , Contaminación del Agua/análisis , Animales , Monitoreo del Ambiente/métodos , Femenino , Fertilización/fisiología , Masculino , Óvulo/fisiología , Espermatozoides/fisiología , Contaminantes del Agua/análisis
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