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1.
Materials (Basel) ; 16(24)2023 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-38138706

RESUMO

This work presents the structural and electrical characterization of K2NiF4-type layered perovskites of LaSrAl1-xMgxO4-δ composition to be used as oxide-ion electrolytes for a solid-oxide fuel cell (SOFC). These perovskites were prepared by mechano-chemical synthesis (ball milling), an alternative to traditional synthesis methods such as citrate-nitrates and solid-state reaction. With these methods, two things are avoided: first, the use of nitrate salts, which are more environmentally harmful than oxide precursors, and second, it saves the series of long thermal treatments associated with solid-state reactions. After grinding the precursors, nanometric particles were obtained with a combination of crystalline regions and amorphous regions; this effect was determined by XRD and TEM, showing that Mg has a positive effect on the phase formation by only mechanical synthesis. R2C4: After sintering, it was found by XRD that the sample x = 0.1 only presents the diffraction peaks corresponding to the desired phase, which shows a phase purity greater than 97%, even higher than that of the standard undoped sample. For x = 0.2 and 0.3, there was a segregation of impurities, possibly by the local migration of La and Sr heavy cations; this was determined by SEM and EDS. The electrical characterization of the sintered pellets was carried out by electrochemical impedance spectroscopy, which determined that the incorporation of Mg in the structure improves the ionic conductivity by three orders of magnitude, obtaining conductivities of 1.6 mS/cm at 900 °C for x = 0.2. Although the improvement in conductivity is considerable, many challenges such as densification, the segregation of impurities, and the study of mechanical and thermal properties must be carried out on these materials to endorse them as solid electrolytes in SOFC.

2.
Evol Appl ; 16(11): 1789-1804, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38029062

RESUMO

The common cockle is a valuable bivalve species inhabiting the Atlantic European coasts. The parasite Marteilia cochillia has devastated cockle beds in the southern Galician (NW Spain) rias since 2012. Previous data suggested that cockles from Ría de Arousa acquired some resilience to this parasite through natural selection after consecutive annual marteiliosis outbreaks and candidate markers associated with marteiliosis resilience were identified using population genomics and transcriptomics approaches. Here, a common garden experiment was performed using a naïve stock (from Ría de Muros-Noia) and an affected stock (from Ría de Arousa) to test this hypothesis. Breeders from both stocks were used to produce seed cohorts at hatchery, which were pre-grown in a raft (outdoor nursery stage) and deployed in two shellfish beds affected by marteiliosis in Ría de Arousa (growing-out stage). In both beds, the naïve stock showed high marteiliosis prevalence and was fully depleted in a short period, while the affected stock barely showed evidence of marteiliosis. A set of 45 SNPs putatively associated with marteiliosis resilience were fitted for MassARRAY genotyping to check their role in the differential resilience detected between both stocks. Though no significant differentiation was found between the naïve and the affected stocks with neutral markers, 28 SNPs showed significant divergence between them, suggesting that these SNPs were involved in directional selection during eight generations (to the most) of marteiliosis pressure (long-term selection). Furthermore, signals of selection were also detected in the naïve stock along the marteiliosis outbreak in the growing-out stage (short-term selection) and six SNPs, all shared with the long-term evaluation, showed consistent signals of differentiation according to the infection severity. Some of these SNPs were located within immune genes pertaining to families such as proteasome, ubiquitin, tumor necrosis factor, and glutathione S-transferase. These resilience-associated markers will be useful to recover cockle production in Galicia.

3.
J Invertebr Pathol ; 201: 108021, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37977281

RESUMO

Drivers of marine disease outbreaks are poorly understood in spite of their growing impact. We present here results from a unique case study examining how cockles Cerastoderma edule have responded to the introduction of the novel protistan Marteilia cochillia, which led in 2012 to cockle fishery collapse in Galician rias. Based on intensive survey for eight years (2011-2019) of two affected shellfish beds, inner and outer in the Ría de Arousa, involving monthly evaluation of cockle health status and estimation of mortality, detailed information is provided of the declining impact of marteiliosis over a wild cockle population with evidence suggesting its increasing resistance. Disease dynamics involved an annual "breaking wave" of prevalence and subsequent cockle mass mortality, causing the near extinction of every recruited cohort. A shift in this pattern, from a severe epidemic towards an endemic profile, was observed in the inner shellfish bed since the cohort that was recruited in 2016, suggesting the hypothesis of increasing marteiliosis resistance through natural selection. Risk factors that may contribute to trigger marteiliosis outbreaks were analysed. Host age and sex did not influence susceptibility to marteiliosis. No clear relationships between environmental conditions (temperature, salinity and upwelling index) or cockle density and disease dynamics were found. Spatial differences in disease dynamics could be due to differences in the abundance of infective stages hypothetically linked to spatial differences in the population dynamics of a putative planktonic intermediate host. All these findings have potential implications for the management of diseased populations.


Assuntos
Cardiidae , Parasitos , Animais , Dinâmica Populacional , Alimentos Marinhos , Frutos do Mar
4.
J Affect Disord ; 299: 425-434, 2022 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-34910958

RESUMO

BACKGROUND: Bipolar disorder (BD) is a psychiatric disorder with complex therapy, besides the treatment with antidepressants induce a mania switch. OBJECTIVE: Investigate the effect of the administration of imipramine (IMI) in rats submitted to intracerebroventricular (ICV) administrations of ouabain (OUA). METHODS: Adult Wistar rats (n = 28) were submitted to only one ICV administration of OUA or artificial cerebrospinal fluid. On the 7th and 9th days following the ICV administration, animals were submitted to a behavioral analysis comprising open field task and forced swimming test. Between the 9th and 14th days, the rats received one daily intraperitoneal administration of IMI or saline (Sal). On the 15th day rats were submitted to the last session of behavioral analysis, followed by euthanasia. The frontal cortex and hippocampus were dissected for the subsequent biochemical assessments: oxidative parameters, and Na+/K+-ATPase activity. RESULTS: OUA administration induced a manic-like effect on the 7th day and a depressive-like behavior on the 14th day. In contrast, IMI administration elicited significant mania switch-like effect on this same stage in animals who received OUA. OUA increased oxidative damage and activity of antioxidant enzymes in the brain of rats. IMI potentialized the oxidative damage of OUA. No significant differences between groups were observed in the Na+/K+-ATPase activity. CONCLUSION: The present study suggests that residual effects from inhibition of the Na+K+ATPase could be involved in the manic-switch observed in bipolar patients. Besides, the OUA model of bipolar disorder could be used to study bipolar disorder in the context of mania switch.


Assuntos
Imipramina , Ouabaína , Animais , Antidepressivos , Modelos Animais de Doenças , Humanos , Imipramina/farmacologia , Mania , Ouabaína/toxicidade , Ratos , Ratos Wistar
5.
Materials (Basel) ; 12(10)2019 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-31108921

RESUMO

The title compounds exhibit a K2NiF4-type layered perovskite structure; they are based on the La1.2Sr0.8InO4+δ oxide, which was found to exhibit excellent features as fast oxide-ion conductor via an interstitial oxygen mechanism. These new Ba-containing materials were designed to present a more open framework to enhance oxygen conduction. The citrate-nitrate soft-chemistry technique was used to synthesize such structural perovskite-type materials, followed by annealing in air at moderate temperatures (1150 °C). The subtleties of their crystal structures were investigated from neutron powder diffraction (NPD) data. They crystallize in the orthorhombic Pbca space group. Interstitial O3 oxygen atoms were identified by difference Fourier maps in the NaCl layer of the K2NiF4 structure. At variance with the parent compound, conspicuous oxygen vacancies were found at the O2-type oxygen atoms for x = 0.2, corresponding to the axial positions of the InO6 octahedra. The short O2-O3 distances and the absence of steric impediments suggest a dual oxygen-interstitial mechanism for oxide-ion conduction in these materials. Conductivity measurements show that the activation energy values are comparable to those typical of ionic conductors working by simple vacancy mechanisms (~1 eV). The increment of the total conductivity for x = 0.2 can be due to the mixed mechanism driving both oxygen vacancies and interstitials, which is original for these potential electrolytes for solid-oxide fuel cells.

6.
Eur. j. anat ; 19(3): 303-308, jul. 2015. ilus
Artigo em Inglês | IBECS | ID: ibc-142285

RESUMO

Juan José Barcia-Goyanes (Santiago de Compostela, 1901 - Valencia, 2003) was a Full Professor of Anatomy (Catedrático de Anatomía) in 1927 at the University of Salamanca and later on, at the University of Valencia, until his retirement. Among his bibliographical data, besides his profound knowledge of Anatomy, he also excelled for his studies on Psychiatry and Neurology and, based on this expertise, he became a pioneer of Spanish Neurosurgery, which he initiated in 1931. In addition, he was Dean of the School of Medicine and Rector of the University of Valencia. In this article, we would like to emphasize his contributions to Anatomy, addressing some of his most important publications. He described for the first time the Incisive Superior Bone, and published crucial conclusions about the foundations of Anatomy and the concept of Form. Importantly, we highlight the Onomatologia anatomica nova, as an opus magnum on the language of Anatomy, which was possible due to his wide knowledge of languages. We also underline, among others, his original study on the greatest work of Vesalius


No disponible


Assuntos
Humanos , Anatomia/história , História da Medicina , Terminologia como Assunto , Modelos Anatômicos
7.
Neurocir. - Soc. Luso-Esp. Neurocir ; 24(6): 262-271, nov.-dic. 2013. ilus, tab
Artigo em Espanhol | IBECS | ID: ibc-127861

RESUMO

El Prof. Juan José Barcia-Goyanes inició la neurocirugía desde la anatomía y la neuropsiquiatría como respuesta a una necesidad de un servicio denominado: «Enfermedades nerviosas» en 1931 en el Hospital General de Valencia. Desde la primera intervención, con los métodos e instrumentos que ya se usaban en Europa y EE.UU., la actividad neuroquirúrgica fue el motor del servicio, donde nacieron las especialidades auxiliares: neurorradiología, neurofisiología, neuropatología y técnicas nuevas como la estereotaxia, la neurocirugía funcional y la palencefalografía. El servicio cumple este año su 80 aniversario. La producción bibliográfica del Prof. Barcia abarcó tanto las materias de neurología, neurocirugía y psiquiatría, como de antropología, pensamiento médico, historia de la medicina, morfología e historia del lenguaje anatómico en su obra de madurez: «Onomatologia anatomica nova», así como una interesante obra poética. Fue miembro fundador de la Sociedad Luso-española de Neurocirugía y de la Sociedad de Neurocirugía de Levante (AU)


Professor Juan José Barcia-Goyanes started neurosurgical practice from anatomy and neuropsychiatry in response to a vacancy at a department known as “Nervous diseases”, in 1931at Hospital General in Valencia, Spain. Since the first intervention, based on the methods and surgical instruments already used in Europe and the U.S.A., the neurosurgical practice became the mainstay of the department, from which other auxiliary specialties emerged, such as neuroradiology, neurophysiology, neuropathology and also new techniques such as stereotactic surgery, functional neurosurgery and palence phalography. This year, the department celebrates its 80th anniversary. The broad spectrum of Prof. Barcia’s scientific work included fields like neurology, neurosurgery and psychiatry, as well as anthropology, medical thought, history of medicine, morphology and history of anatomical language in his work “Onomatologica anatomica nova”, in addition to an interesting poetic work. He was a founding member of the Luso-Spanish Neurosurgical Society and the Neurosurgical Societyof Levante (AU)


Assuntos
Humanos , Neurocirurgia/história , Doenças do Sistema Nervoso/história , História da Medicina , Espanha , Faculdades de Medicina/história , Educação Médica/história
8.
An. Fac. Med. (Perú) ; 74(4): 327-330, oct.-dic. 2013. ilus
Artigo em Espanhol | LILACS-Express | LILACS, LIPECS | ID: lil-702453

RESUMO

La estenosis subaórtica es una lesión cardiaca poco frecuente, en el cual el tracto de salida del ventrículo izquierdo está estrechado por la presencia de un anillo fibroso o fibromuscular. Constituye 8 a 20% de todas las formas de obstrucción al tracto de salida del ventrículo izquierdo. La cirugía ha sido considerada el tratamiento de elección cuando el gradiente pico es mayor de 50 mmHg o en pacientes que, con gradientes menores, presentan progresión de la insuficiencia aórtica o dilatación de los diámetros ventriculares, disfunción ventricular o síntomas. Presentamos el caso de un paciente menor de edad, portador de estenosis subaórtica por membrana, con síntomas de insuficiencia cardiaca y función ventricular izquierda muy comprometida, en la que se realizó el tratamiento percutáneo, alternativo al quirúrgico, con resultado exitoso. Constituye el primer caso reportado en el país de tratamiento percutáneo con balón y con evolución favorable.


Discrete subaortic stenosis is a rare cardiac lesion with left ventricle outflow narrowed by the presence of a muscular or fibrous ring. It accounts for 8-20% of all forms of left ventricle outflow tract obstruction. Surgery is considered the treatment of choice when the peak gradient is over 50 mmHg or in patients with lower gradients and either progression of aortic regurgitation, dilated ventricular diameters, left ventricular dysfunction or symptoms. We report the case of a child with membrane subaortic stenosis and symptoms of heart failure and compromised left ventricular function, in whom percutaneous balloon dilatation was performed as an alternative to surgery. This is the first case reported in the country with successful outcome.

9.
Neurocirugia (Astur) ; 24(6): 262-71, 2013.
Artigo em Espanhol | MEDLINE | ID: mdl-23154130

RESUMO

Professor Juan José Barcia-Goyanes started neurosurgical practice from anatomy and neuropsychiatry in response to a vacancy at a department known as "Nervous diseases", in 1931 at Hospital General in Valencia, Spain. Since the first intervention, based on the methods and surgical instruments already used in Europe and the U.S.A., the neurosurgical practice became the mainstay of the department, from which other auxiliary specialties emerged, such as neuroradiology, neurophysiology, neuropathology and also new techniques such as stereotactic surgery, functional neurosurgery and palencephalography. This year, the department celebrates its 80th anniversary. The broad spectrum of Prof. Barcia's scientific work included fields like neurology, neurosurgery and psychiatry, as well as anthropology, medical thought, history of medicine, morphology and history of anatomical language in his work "Onomatologica anatomica nova", in addition to an interesting poetic work. He was a founding member of the Luso-Spanish Neurosurgical Society and the Neurosurgical Society of Levante.


Assuntos
Neurocirurgia/história , História do Século XX , Espanha
10.
Rev. neurol. (Ed. impr.) ; 52(5): 275-282, 1 mar., 2011. tab, graf
Artigo em Espanhol | IBECS | ID: ibc-87172

RESUMO

Introducción y objetivo. Entre las opciones terapéuticas para pacientes con schwannoma vestibular se encuentra la radiocirugía. Presentamos así nuestra experiencia en el tratamiento de esta patología con esta técnica. Pacientes y métodos. Estudio retrospectivo de 20 pacientes (11 mujeres y 9 varones; edad media: 55,15 años) con diagnóstico de schwannoma vestibular, que recibieron tratamiento con radiocirugía con acelerador lineal desde abril del 2005 hasta diciembre del 2008. El tiempo de seguimiento fue de 12-42 meses, tanto clínico, con valoración de los pares craneales VII (escala de House-Brackmann) y VIII (escala de Gardner-Robertson), como radiológico (con medición del volumen tumoral). Se emplearon el test exacto de Fisher y la prueba de regresión logística para el análisis estadístico. Resultados. El 25% presentó algún empeoramiento de la audición. Cinco pacientes presentaron tumores grandes en el momento del tratamiento (iguales o mayores que 3,5 cm3), de los cuales cuatro empeoraron de cefalea, inestabilidad, mareos/vértigo, parestesias faciales y acúfenos, con una asociación estadísticamente significativa (p < 0,05) en las pruebas aplicadas. A partir del primer año del tratamiento, se observó una tendencia a la disminución del volumen tumoral, sin observarse ningún crecimiento de la lesión a medio-largo plazo, con control local del 100%. Conclusiones. La radiocirugía se ofrece como una alternativa de tratamiento para pacientes con schwannoma vestibular de tamaño adecuado, con alta seguridad terapéutica, que emplea dosis relativamente bajas de radiación, índice bajo de complicaciones y buen control del crecimiento tumoral a medio plazo (AU)


Introduction and aim. Radiosurgery is among the treatment options for patients with vestibular schwannoma. We present the experience in our institution in the treatment of this disease with this technique. Patients and methods. A retrospective study was made including 20 patients (11 women and 9 men; median age: 55.15 years-old) with vestibular schwannoma who received linear accelerator radiosurgery treatment since April 2005 until December 2008. Follow-up period was between 12 and 42 months, considering clinical examination of cranial nerves VII (House-Brackmann scale) and VIII (Gardner-Robertson scale) as well as radiological findings (considering tumor volume). For statistical analysis, the Fisher’s exact test and logistic regression test were used. Results. Certain worsening of hearing function was present in 25% of the patients. Five patients had large tumors at the moment of the treatment (equal or larger than 3.5 cm3), from which four deteriorated from headache, unsteady gait, dizziness/vertigo, facial numbness and tinnitus, with statistical significance (p < 0.05). From the first year of treatment on, there was a tumor volume decrease tendency, with no tumor growth in the medium/long term follow-up, achieving a local control rate of 100%. Conclusions. Radiosurgery has become an alternative in the treatment of patients with vestibular schwannoma of appropriate size, with high safety level, using low radiation doses, low rate of complications and good tumor control rate in the medium term follow-up (AU)


Assuntos
Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Radiocirurgia/métodos , Neuroma Acústico/cirurgia , Aceleradores de Partículas , Recidiva Local de Neoplasia/prevenção & controle , Estudos Retrospectivos
11.
Rev. bras. cancerol ; 51(4): 305-311, out.-dez. 2005. ilus, tab, graf
Artigo em Português | LILACS | ID: lil-555177

RESUMO

Objetivo: relatar nossa experiência com a colocação e o uso do cateter venoso central de longa permanência(CVCLP), implantado através das veias do braço. Pacientes e Métodos: trata-se de um trabalho retrospectivo em que foram analisados 586 cateteres implantados em crianças com câncer, de janeiro de 1995 a dezembro de 1999, no HC I - INCA. Resultados: dos 586 CVCLP implantados em crianças com câncer, 91,5 % foram inseridos através das veias do braço (536), 45 (8 %) implantados no tórax e 5 (1 %) em outros sítios. As veias de escolha para o implante do cateter no braço foram as braquiais. Os resultados em relação às complicações (infecção, obstrução, exteriorização do anel fixador, ruptura do cateter, migração, entre outras), foram similares àqueles da literatura quando implantados no tórax. Conclusão: recomendamos a colocação do cateter no braço como primeira opção para colocação de cateteres venosos centrais de longa permanência para crianças com câncer, uma vez que mostrou-se mais seguro, confortável, esteticamente mais tolerável e permitiu maior mobilidade aos pacientes, quando em uso do cateter do que os implantados no tórax. Implicação clínica: propomos a opção da colocação do CVCLP no braço como a primeira escolha por acharmos ser mais segura, mais confortável e eficiente, do que os implantados no tórax, para as crianças com câncer, que necessitem de um acesso venoso por tempo prolongado.


Objective: To report our experience with insertion and use of LTCVC in the arm. Pacients and Methods: It is aretrospective study. We analyzed 586 LTCVC inserted on children with cancer, from January 1995 to December1999. Results: From a total of 586 inserted LTCVC; 536 (91,5%) were in the arm, 45 in the thorax and 5 wereinserted in other sites. The vein of choice for the arm was the brachial vein, on its proximal third. All LTCVC were inserted at operating rooms, under general anesthesia. The tip of the catheter was localized on superior cava vein under fluoroscopy. Our experience with the site of insertion on the arm had demonstrated that this site is safe,comfortable, esthetically better, and that it allows more mobility to the patients when it is activated. The resultsregarding infection rates for arm insertionare similar to those found on the literature for LTCVC thorax inserted.Conclusion: We indicate the arm (brachial vein) as the site of choice for inserting LTCVC for children with cancer. Clinical Implication: The insertion of LTCVC in the arm is a safe and efficient option for inserting LTCVC in children with cancer.


Assuntos
Humanos , Masculino , Feminino , Pré-Escolar , Criança , Braço , Criança , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central , Qualidade de Vida , Neoplasias/terapia
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