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2.
Sci Rep ; 13(1): 14366, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37658090

RESUMO

Superconducting microwave resonators are crucial elements of microwave circuits, offering a wide range of potential applications in modern science and technology. While conventional low-T[Formula: see text] superconductors are mainly employed, high-T[Formula: see text] cuprates could offer enhanced temperature and magnetic field operating ranges. Here, we report the realization of [Formula: see text] superconducting coplanar waveguide resonators, and demonstrate a continuous evolution from a lossy undercoupled regime, to a lossless overcoupled regime by adjusting the device geometry, in good agreement with circuit model theory. A high-quality factor resonator was then used to perform electron spin resonance measurements on a molecular spin ensemble across a temperature range spanning two decades. We observe spin-cavity hybridization indicating coherent coupling between the microwave field and the spins in a highly cooperative regime. The temperature dependence of the Rabi splitting and the spin relaxation time point toward an antiferromagnetic coupling of the spins below 2 K. Our findings indicate that high-Tc superconducting resonators hold great promise for the development of functional circuits. Additionally, they suggest novel approaches for achieving hybrid quantum systems based on high-T[Formula: see text] superconductors and for conducting electron spin resonance measurements over a wide range of magnetic fields and temperatures.

3.
J Chromatogr A ; 1705: 464216, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37480726

RESUMO

A micro-solid phase extraction (micro-SPE) device packed with a C18 sorbent (10 mg) has been developed for the enrichment and purification of organic water pollutants prior to their analysis using a portable liquid chromatograph with a dual UV detector. To this end, the sorbent was immobilized at the inlet of a 4 mm syringe filter (0.20 µm), which was modified to reduce its internal volume. The filter was coupled to the needle of the chromatograph. After loading the sample and cleaning the sorbent for analyte purification, the device was installed into the injection port of the chromatograph, and the target compounds were desorbed and transferred directly to the chromatographic column with a small volume of organic solvent. Under optimized conditions, sample volumes as large as 50 mL could be processed with the micro-SPE device, while the analytes were desorbed with only 60 µL of methanol. As a result, efficient preconcentration could be reached, as demonstrated for different water contaminants, namely aclonifen, bifenox, tritosulfuron, triflusulfuron-methyl and caffeine. The proposed micro-SPE device was applied to the analysis of different types of water (river, well, sea, ditch and wastewater). The recoveries of the target compounds in samples ranged from 76 % to 109 %, which allowed their detection at low to sub µg/L levels. All operations were carried out manually, and thus, no additional laboratory instruments such as centrifuges, stirrers or evaporators were required. This proof-of-concept study shows that the proposed micro-SPE approach can be considered a reliable and effective option for the on-site analysis of pollutants in environmental water samples by portable liquid chromatography.


Assuntos
Extração em Fase Sólida , Poluentes Químicos da Água , Extração em Fase Sólida/métodos , Cromatografia Líquida , Água/química , Solventes/análise , Cromatografia Líquida de Alta Pressão/métodos , Poluentes Químicos da Água/análise
4.
Chemosphere ; 336: 139238, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37330060

RESUMO

The degradation of the diphenyl-ether herbicides aclonifen (ACL) and bifenox (BF) in water samples has been studied under different laboratory conditions, using in-tube solid-phase microextraction (IT-SPME) coupled to capillary liquid chromatography (capLC). The working conditions were selected in order to detect also bifenox acid (BFA), a compound formed as a result of the hydroxylation of BF. Samples (4 mL) were processed without any previous treatment, which allowed the detection of the herbicides at low ppt levels. The effects of temperature, light and pH on the degradation of ACL and BF have been tested using standard solutions prepared in nanopure water. The effect of the sample matrix has been evaluated by analysing different environmental waters spiked with the herbicides, namely ditch water, river water and seawater. The kinetics of the degradation have been studied and the half-life times (t1/2) have been calculated. The results obtained have demonstrated that the sample matrix is the most important parameter affecting the degradation of the tested herbicides. The degradation of both ACL and BF was much faster in ditch and river water samples, where t1/2 values of only a few days were observed. However, both compounds showed a better stability in seawater samples, where they can persist for several months. In all matrices ACL was found to be more stable than BF. In samples where BF had been substantially degraded, BFA was also detected, although the stability of this compound was also limited. Other degradation products have been detected along the study.


Assuntos
Herbicidas , Poluentes Químicos da Água , Herbicidas/química , Éteres Fenílicos/análise , Água/análise , Poluentes Químicos da Água/análise
5.
Chemosphere ; 334: 138973, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37211159

RESUMO

Mangroves act as buffer areas for marine systems, providing a barrier to contamination from continental sources by retaining metal pollutants. This study evaluates metal and semimetal contamination in the water column and sediments of four mangroves located on the volcanic island of São Tomé. Several metals had a widespread distribution, with occasional high concentrations, linked to potential sources of contamination. However, the two smaller mangroves, located in the northern part of the island, tended to have high metal concentrations. Arsenic and chromium concentrations were notably concerning, particularly if we consider this is an isolated and non-industrialized island. This work highlights the need for further assessments and a better understanding of processes and implications of metal contamination in mangroves. This assumes a particular relevance in areas that have specific geochemical compositions (i.e., volcanic origin) and in developing countries, where people often rely directly and heavily on resources obtained from these ecosystems.


Assuntos
Metais Pesados , Poluentes Químicos da Água , Humanos , Metais Pesados/análise , Ecossistema , Água , Sedimentos Geológicos/química , Poluentes Químicos da Água/análise , África Central , Monitoramento Ambiental , Medição de Risco
6.
Sci Rep ; 12(1): 16423, 2022 09 30.
Artigo em Inglês | MEDLINE | ID: mdl-36180562

RESUMO

Estuaries are highly productive ecosystems, which are strongly affected by several anthropogenic pressures. Phytoplankton is a key element for assessing the ecological quality status in these transitional waters. Moreover, understanding physico-chemical and biological drivers is crucial to disentangle their effect on the structure of phytoplankton community. The present work aims to study the effect of the main physico-chemical drivers on the phytoplankton community structure and dynamics in a temperate well-mixed estuary (Sado Estuary). Four sampling stations were analyzed monthly in three regions of the estuary, from 2018 to 2019. Surface water samples were collected to analyze the phytoplankton community and several concomitant physico-chemical parameters. Temperature, turbidity, salinity, and nutrients availability were the drivers that best explained the spatio-temporal patterns observed in the phytoplankton community. The upper estuary was characterized by higher phytoplankton cell abundances and biomass. Three phytoplankton groups stood out in the characterization of the estuarine assemblages: diatoms, cryptophytes, and dinoflagellates. Diatoms were the dominant group most of the year, being dominated by small cell species (single and chain-forming) upstream, and by larger chain-forming species downstream. Cryptophytes had a high contribution to the community in the inner regions of the estuary, while dinoflagellates contributed more for the community composition downstream, where high abundances of harmful algal species were sporadically found. Previous studies on the phytoplankton community dynamics in this estuary are limited to the 1990s. Thus, the present study provides insight into changes in the dominant phytoplankton groups of the Sado Estuary in the last 25 years, namely an increase in cryptophytes over diatoms in the inner estuarine regions, and an increase in dinoflagellates near the estuary mouth.


Assuntos
Diatomáceas , Dinoflagellida , Ecossistema , Estuários , Fitoplâncton/química , Portugal , Estações do Ano , Água
7.
Nat Mater ; 21(2): 188-194, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34857910

RESUMO

The Josephson effect results from the coupling of two superconductors across a spacer such as an insulator, a normal metal or a ferromagnet to yield a phase coherent quantum state. However, in junctions with ferromagnetic spacers, very long-range Josephson effects have remained elusive. Here we demonstrate extremely long-range (micrometric) high-temperature (tens of kelvins) Josephson coupling across the half-metallic manganite La0.7Sr0.3MnO3 combined with the superconducting cuprate YBa2Cu3O7. These planar junctions, in addition to large critical currents, display the hallmarks of Josephson physics, such as critical current oscillations driven by magnetic flux quantization and quantum phase locking effects under microwave excitation (Shapiro steps). The latter display an anomalous doubling of the Josephson frequency predicted by several theories. In addition to its fundamental interest, the marriage between high-temperature, dissipationless quantum coherent transport and full spin polarization brings opportunities for the practical realization of superconducting spintronics, and opens new perspectives for quantum computing.

8.
Nat Commun ; 11(1): 658, 2020 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-32005810

RESUMO

The term tunnel electroresistance (TER) denotes a fast, non-volatile, reversible resistance switching triggered by voltage pulses in ferroelectric tunnel junctions. It is explained by subtle mechanisms connected to the voltage-induced reversal of the ferroelectric polarization. Here we demonstrate that effects functionally indistinguishable from the TER can be produced in a simpler junction scheme-a direct contact between a metal and an oxide-through a different mechanism: a reversible redox reaction that modifies the oxide's ground-state. This is shown in junctions based on a cuprate superconductor, whose ground-state is sensitive to the oxygen stoichiometry and can be tracked in operando via changes in the conductance spectra. Furthermore, we find that electrochemistry is the governing mechanism even if a ferroelectric is placed between the metal and the oxide. Finally, we extend the concept of electroresistance to the tunnelling of superconducting quasiparticles, for which the switching effects are much stronger than for normal electrons. Besides providing crucial understanding, our results provide a basis for non-volatile Josephson memory devices.

9.
Nat Mater ; 18(9): 948-954, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31086324

RESUMO

In multi-orbital materials, superconductivity can exhibit several coupled condensates. In this context, quantum confinement in two-dimensional superconducting oxide interfaces offers new degrees of freedom to engineer the band structure and selectively control the occupancy of 3d orbitals by electrostatic doping. Here, we use resonant microwave transport to extract the superfluid stiffness of the (110)-oriented LaAlO3/SrTiO3 interface in the entire phase diagram. We provide evidence of a transition from single-condensate to two-condensate superconductivity driven by continuous and reversible electrostatic doping, which we relate to the Lifshitz transition between 3d bands based on numerical simulations of the quantum well. We find that the superconducting gap is suppressed while the second band is populated, challenging Bardeen-Cooper-Schrieffer theory. We ascribe this behaviour to the existence of superconducting order parameters with opposite signs in the two condensates due to repulsive coupling. Our findings offer an innovative perspective on the possibility to tune and control multiple-orbital physics in superconducting interfaces.

10.
Rev. chil. ortop. traumatol ; 60(1): 27-31, mar. 2019. ilus
Artigo em Espanhol | LILACS | ID: biblio-1146579

RESUMO

La osificación heterotópica (OH), es la formación anormal de hueso maduro dentro de tejidos blandos extra esqueléticos donde normalmente no existe tejido óseo. Varias formas de OH han sido descritas de acuerdo a su presentación clínica, localización y ocurrencia progresiva o aislada. Su presentación en pacientes sometidos a inmovilización prolongada en el contexto de coma farmacológicamente inducido, en ausencia de lesiones del sistema nervioso central, es poco habitual. Presentamos el caso de una paciente de 40 años, sexo femenino, sin antecedentes mórbidos, que presenta episodio de pancreatitis aguda grave, manejada en UCI. Producto de lo anterior, requiere coma farmacológicamente inducido por 3 meses y hospitalizaciones reiteradas y prolongadas durante los 10 meses siguientes. Durante 3 años desde la resolución de su cuadro inicial evoluciona con alteración progresiva de la marcha y rigidez de la extremidad inferior derecha, sin eventos traumáticos durante ese período. Se objetiva mediante radiografía y TAC foco de OH coxofemoral derecha. Se resuelve de forma quirúrgica y biopsia de pieza operatoria confirma el diagnóstico. La paciente logra buena recuperación posterior. NIVEL DE EVIDENCIA: IV


Heterotopic ossification (HO) is the abnormal formation of mature bone within extraskeletal soft tissues where bone does not exist. Various presentation of HO have been described according to the clinical settings and location of the lesions, and progressive or isolated occurrence. A rare form of presentation occurs in induced coma patients with long-term immobilization and without central nervous system injuries. We present the case of a 40 years old female patient, without previous morbidity, who develop a severe acute pancreatitis. The patient requires an intensive care unit management (ICU) and a 3-month pharmacology induced coma and reiterative and prolonged hospitalizations during the next 8 months. During 3 years after resolution of her base disease, patient develops a progressive step claudication and a hip rigidity in adduction and external rotation. A coxofemoral HO focus is confirmed by radiology and CT. A surgical treatment of HO was performed, and the initial diagnose confirmed by anatomic pathology after biopsy of the injury. Patient had a favorable outcome.


Assuntos
Humanos , Feminino , Adulto , Pancreatite/complicações , Ossificação Heterotópica/cirurgia , Ossificação Heterotópica/etiologia , Quadril , Doença Aguda , Ossificação Heterotópica/diagnóstico por imagem
11.
Psychiatry Res ; 273: 586-594, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30716598

RESUMO

AIM: The main goal of this study was to evaluate the effectiveness of a cognitive motivational treatment program. METHOD: A randomized, controlled, single-blind clinical trial was carried out. A total of 104 patients were recruited to take part in the trial, of whom ultimately 62 patients were allocated into two groups and finished the study. An initial assessment was carried out before patients were randomly placed in one of two groups for the clinical trial: (a) PIPE program plus routine care; and (b) routine care only. Clinical assessments were performed at baseline at 6 months, 1 year and follow-ups, at 18 months and 5 years). RESULTS: MANCOVA analysis of tests repeated 18 months after the start of the intervention detected significant differences between the two groups in terms of clinical variables, everyday functioning and relapses. These differences remained upon follow-up measurements taken five years after the start of the trial. CONCLUSIONS: The present study offers scientific evidence for cognitive-motivational therapy's effectiveness as a treatment for clinical symptoms in the early stages of psychosis. PIPE intervention may contribute to long-term clinical improvement and stability.


Assuntos
Terapia Cognitivo-Comportamental/métodos , Entrevista Motivacional/métodos , Esquizofrenia/diagnóstico , Esquizofrenia/terapia , Psicologia do Esquizofrênico , Adulto , Feminino , Seguimentos , Humanos , Masculino , Método Simples-Cego , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
12.
Sci Total Environ ; 652: 1077-1089, 2019 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-30586795

RESUMO

Polycyclic aromatic hydrocarbons (PAHs) are organic compounds that tend to rapidly associate to particulate organic matter in sediments due to their hydrophobic characteristics, inducing toxic, carcinogens and mutagens effects to many living organisms. The monitoring and identification of the sources of PAHs in sediments is relevant especially because they are the main reservoir and secondary source of contamination of aquatic systems. To identify the sources there are different methods for data treatment that complement each other: evaluation of profiles distribution, source-specific diagnostic ratios of PAHs and principal component analysis (PCA). To demonstrate the applicability of these different methods, concentrations of PAHs from sediments of four Portuguese estuarine systems were used: Ria de Aveiro, Tagus River, Sado River and Ria Formosa, in order to identify the sources.

13.
Mol Hum Reprod ; 24(4): 203-210, 2018 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-29438521

RESUMO

STUDY QUESTION: Is the expression of steroidogenic enzyme 17α-Hydroxylase/17,20-Lyase (CYP17A1) down-regulated in Leydig cells (LCs) of men with spermatogenic failure and compensated impairment of LC function, i.e. a low testosterone to LH (T/LH) ratio? SUMMARY ANSWER: Although the transcriptional expression of CYP17A1 is increased, its protein expression is decreased, in isolated LCs of men with spermatogenic failure and reduced serum T/LH. WHAT IS KNOWN ALREADY: Primary spermatogenic defects have been associated with functional and morphological abnormalities of LCs, characterized by decreased serum testosterone (T) levels, decreased T/LH, increased 17ß-estradiol (E2) and E2/T ratio, and larger clusters of LCs (LC hyperplasia). CYP17A1 is a key enzyme in the testosterone pathway and has been implicated in the steroidogenic lesion produced by E2 stimulation. STUDY DESIGN, SIZE, DURATION: We studied 18 azoospermic patients with Sertoli cell-only syndrome (SCOS) and signs of LC dysfunction (cases) and 10 obstructive azoospermic/oligozoospermic men with normal spermatogenesis (controls). The SCOS patients were sub-grouped into 9 cases with T/LH <2 and 9 cases with T/LH ≥2. All of the men underwent testicular biopsy for sperm retrieval at the Reproductive Unit of a University Hospital. PARTICIPANTS/MATERIALS, SETTING, METHODS: The transcriptional expression of CYP17A1 and SF-1 (steroidogenic factor 1) was quantified by SYBR®Green-based qPCR in LCs isolated by laser capture microdissection (LCM), and relative expression to the control pool was assessed. CYP17A1 protein expression was semi-quantified by indirect immunofluorescence (IFI) using Image-Pro Plus v7.0 (Media Cybernetics) in testicular tissue. FSH and LH serum concentrations, and serum and intratesticular T (ITT) and E2 (ITE2) were measured by IRMA and RIA, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: Relative CYP17A1 mRNA expression was increased in cases with T/LH <2 compared to cases with T/LH ≥2, by a mean of 3.3-fold (P = 0.002). No corresponding increase in protein expression was found; in fact, CYP17A1 immunostaining intensity assessed by the Integrated Optical Density (IOD) parameter was lower in the cases with T/LH <2 compared to controls (P = 0.008). Relative SF-1 mRNA expression was similar in both case subgroups. CYP17A1 mRNA expression correlated with ITE2 and intratesticular E2/T (r = 0.536; P = 0.026 and r = 0.542; P = 0.016, respectively), while an inverse association was observed for ITE2 and protein level expression (r = -0.421; P = 0.05). LARGE SCALE DATA: Not applicable. LIMITATIONS REASONS FOR CAUTION: We should interpret the results of the semi-quantification of immunofluorescent staining by Image-Pro Plus software with caution, because it is a semi-quantitative method that may have certain difficulties regarding the disposition of protein in the cells. However, it is not influenced by variations in the number of cells that express the protein, as could be the case of western blot analysis in testicular tissue. WIDER IMPLICATIONS OF THE FINDINGS: Dysfunctional LCs of men with SCOS show post-transcriptional deregulation of CYP17A1, with increased mRNA and decreased protein expression, which may be modulated by increased ITE2 levels. In addition, transcriptional expression of CYP17A1 was not associated with changes in SF-1 mRNA expression. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Fund for Scientific and Technological Development (FONDECYT) of Chile to A.C. [grant number 1120176]. The authors declare no conflict of interest.


Assuntos
Células Intersticiais do Testículo/metabolismo , Síndrome de Células de Sertoli/metabolismo , Esteroide 17-alfa-Hidroxilase/metabolismo , Humanos , Hormônio Luteinizante/metabolismo , Masculino , Fator Esteroidogênico 1/metabolismo , Testosterona/metabolismo
14.
Nat Commun ; 9(1): 407, 2018 01 29.
Artigo em Inglês | MEDLINE | ID: mdl-29379023

RESUMO

In LaAlO3/SrTiO3 heterostructures, a gate tunable superconducting electron gas is confined in a quantum well at the interface between two insulating oxides. Remarkably, the gas coexists with both magnetism and strong Rashba spin-orbit coupling. However, both the origin of superconductivity and the nature of the transition to the normal state over the whole doping range remain elusive. Here we use resonant microwave transport to extract the superfluid stiffness and the superconducting gap energy of the LaAlO3/SrTiO3 interface as a function of carrier density. We show that the superconducting phase diagram of this system is controlled by the competition between electron pairing and phase coherence. The analysis of the superfluid density reveals that only a very small fraction of the electrons condenses into the superconducting state. We propose that this corresponds to the weak filling of high-energy dxz/dyz bands in the quantum well, more apt to host superconductivity.

15.
Cuad. psicol. deporte ; 17(3): 65-72, sept. 2017. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-169669

RESUMO

El objetivo del estudio fue analizar la influencia de la perspectiva de visionado (egocéntrica o alocéntrica) sobre el comportamiento motor de una muestra reducida de tenistas noveles cuando percibieron servicios de tenis video-proyectados en laboratorio. Específicamente, un grupo de tenistas (n=6) percibió la secuencia de ensayos con una perspectiva egocéntrica. En cambio, el otro grupo de tenistas (n=6) percibió la misma secuencia de servicios con una perspectiva alocéntrica. Los participantes debían de iniciar su movimiento, rápida y precisamente, cuando identificaran la dirección final la pelota. Los resultados mostraron que los tenistas que percibieron los servicios con una perspectiva alocéntrica consiguieron tiempos de reacción significativamente menores y una precisión de la respuesta mayor en relación a la perspectiva egocéntrica. Se recomienda incluir proyecciones alocéntricas de visionado en el diseño de los entrenamientos perceptivos en el deporte ya que favorecen el rendimiento de los deportistas en la tarea, mediante la producción de inicios rápidos y precisos de la respuesta (AU)


The aim of the study was to address the influence of the viewing perspective (egocentric or alocentric one) in the motor behavior of a reduced sample of novel tennis players when they perceived video-projected services in a laboratory setting. Specifically, a group of tennis players (n = 6) perceived the sequence of rallies with an egocentric perspective. In contrast, another group of players (n = 6) perceived the same sequence with an alocentric perspective. Participants were required to initiate the movement, quickly and precisely, when they identify the final direction of the ball. The results showed that the players, who perceived the rallies with an alocentric viewing, achieved significantly lower reaction times and higher response accuracy than an egocentric perspective. It is recommended to include alocentric viewing projections in the design of perceptual trainings in the sport as they enhance the performance of athletes in the task by producing fast movements and accurate responses (AU)


O objetivo do estudo foi analise a influência da perspectiva de (egocêntrico ou alocêntrica) de visão sobre o comportamento motor de uma pequena amostra de jogadores novatos quando perceberam serviços de vídeo de tênis projetado por laboratório. Especificamente, um grupo de jogadores (n = 6), viu a sequência do ensaio com uma perspectiva autocentrada. Em vez disso, outro grupo de jogadores (n = 6), viu a mesma sequência de serviços com uma perspectiva alocêntrica. Os participantes foram obrigados a iniciar o movimento, de forma rápida e identificar com precisão quando a direcção final da bola. Os resultados mostraram que os jogadores que perceberam uma alocêntrica perspectiva serviços alcançado significativamente menores tempos de reação e precisão do maior resposta em relação à perspectiva egocêntrica. Recomenda-se incluem projeções alocêntrica visualização no projeto de formação perceptual no esporte uma vez que aumentam o desempenho dos atletas na tarefa de produzir resposta inicial rápida e precisa (AU)


Assuntos
Humanos , Adulto Jovem , Adulto , Tênis/psicologia , Desempenho Psicomotor/fisiologia , Percepção/fisiologia , Estudantes/psicologia , 28574/métodos , Desempenho Atlético/psicologia , Recursos Audiovisuais , Gravação em Vídeo/métodos , Análise de Dados/métodos , 28599 , Estatísticas não Paramétricas
16.
Actas urol. esp ; 41(2): 97-102, mar. 2017. tab, ilus
Artigo em Espanhol | IBECS | ID: ibc-160618

RESUMO

Objetivo: Modelos animales han demostrado que existe una asociación entre disfunción eréctil y acumulación de grasa bajo la albugínea del pene, pudiendo provocar fuga venosa y pérdida de rigidez del pene. En este estudio se llevó a cabo una comparación de la histología de los cuerpos cavernosos bajo la albugínea de pacientes con disfunción eréctil refractarios a tratamiento médico sometidos a implante de prótesis de pene, y pacientes con enfermedad de Peyronie, sin disfunción eréctil, sometidos a corporoplastia. Materiales y métodos: Se incluyeron 17 pacientes con disfunción eréctil y 14 pacientes potentes con enfermedad de Peyronie. Se recolectaron muestras de tejido cavernoso bajo la túnica albugínea en cada cirugía, las cuales fueron analizadas por un uropatólogo en búsqueda de adipocitos subalbugíneos. Se llevó a cabo un análisis bivariado para comparar características de ambos grupos. Se calcularon las odds ratio con un modelo multivariado de regresión logística. Un valor de p < 0,05 fue considerado significativo. Resultados: Once pacientes (11/17) en el grupo de disfunción eréctil presentaron adipocitos en la histología, mientras solo un paciente (1/14) lo presentó en el grupo control (p < 0,05). El análisis multivariado mostró una odds ratio de 40,72; IC 95%: 2,28-727,29 (p = 0,012). Conclusiones: Alteraciones en los andrógenos provocan cambios estructurales en el pene, llevando a apoptosis y desdiferenciación de músculo trabecular hacia adipocitos. Este es el primer estudio prospectivo en humanos que muestra una asociación entre grasa subalbugínea y disfunción eréctil. La fuga venosa secundaria a este fenómeno podría influir en la disfunción eréctil, especialmente en pacientes que no responden a tratamiento médico


Objectives: Animal models have shown that erectile dysfunction is associated with adipocyte accumulation under tunica albugínea, which could be involved in venous leakage and loss of penile rigidity. In the current sudy, we compared the histology of the penile sub-albuginean region of drug-refractory erectile dysfunction patients undergoing penile prosthesis implantation with potent patients with Peyronie's disease undergoing curvature correction procedures. Materials and methods. Seventeen refractory erectile dysfunction patients and fourteen potent patients with Peyronie's disease were recruited. Sub-albuginean tissue samples were taken in each surgery. An expert uropathologist analysed each section. A bivariate analysis was performed. Multivariate logistic regression was used to calculate adjusted odds ratios; P value <.05 was considered significant. Results: Eleven patients (11/17) in the case group presented cavernous fat cell accumulation, while only one patient (1/14) in the control group presented this finding (P < .05). Adjusted odds ratio for erectile dysfunction was 40.72; 95% CI 2.28-727.29 (P = .012). Conclusions: Different studies have shown that androgen disruption could be involved in penile structural changes, leading to trabecular smooth muscle apoptosis and trans or de-differentiation into adipocytes. This is the first prospective study in humans to report an association between erectile dysfunction and sub-albuginean adipocyte accumulation. Venous leakage secondary to this phenomenon could be a factor in the pathophysiology of erectile dysfunction, especially in patients that do not respond to medical therapy


Assuntos
Humanos , Animais , Masculino , Adulto , Idoso , Adipócitos/patologia , Disfunção Erétil/complicações , Disfunção Erétil/diagnóstico , Disfunção Erétil/veterinária , Antagonistas de Androgênios/análise , Modelos Animais , Índice de Massa Corporal , Razão de Chances , Análise Multivariada , Modelos Logísticos , Estudos Prospectivos , Declaração de Helsinki , Consentimento Livre e Esclarecido/normas
17.
Hum Reprod ; 32(2): 465-475, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28057878

RESUMO

STUDY QUESTION: Are copy number variations (CNVs) in the pseudoautosomal regions (PARs) frequent in subjects with Y-chromosome microdeletions and can they lead to abnormal stature and/or neuropsychiatric disorders? SUMMARY ANSWER: Only subjects diagnosed with azoospermia factor (AZF)b+c deletions spanning to the end of the Y chromosome (i.e. terminal deletions) harbor Y isochromosomes and/or cells 45,X that lead to pseudoautosomal gene CNVs, which were associated with abnormal stature and/or neuropsychiatric disorders. WHAT IS KNOWN ALREADY: The microdeletions in the long arm of the Y chromosome (Yq) that include the loss of one to three AZF regions, referred to as Yq microdeletions, constitute the most important known etiological factor for primary spermatogenic failure. Recently, controversy has arisen about whether Yq microdeletions are associated with gain or loss of PAR genes, which are implicated in skeletal development and neuropsychiatric function. STUDY DESIGN, SIZE, DURATION: We studied a cohort of 42 Chilean patients with complete AZF deletions (4 AZFa, 4 AZFb, 23 AZFc, 11 AZFb+c) from a university medical center, diagnosed over a period of 15 years. The subjects underwent complete medical examinations with special attention to their stature and neuropsychiatric function. PARTICIPANTS/MATERIALS, SETTING, METHODS: All subjects were characterized for Yq breakpoints by PCR, and for CNVs in PARs by multiplex ligation-dependent probe amplification (MLPA), followed by qPCR analysis for genes in PAR1 (SHOX and ZBED1), PAR2 (IL9R) and two single copy genes (SRY and DDX3Y, respectively located in Yp11.3 and AZFa). In addition, karyotypes revision and fluorescence in situ hybridization (FISH) for SRY and centromeric probes for X (DXZ1) and Y (DYZ3) chromosomes were performed in males affected with CNVs. MAIN RESULTS AND THE ROLE OF CHANCE: We did not detect CNVs in any of the 35 AZF-deleted men with interstitial deletions (AZFa, AZFb, AZFc or AZFb+c). However, six of the seven patients with terminal AZFb+c deletions showed CNVs: two patients showed a loss and four patients showed a gain of PAR1 genes, with the expected loss of VAMP-7 in PAR2. In these patients, the Yq breakpoints localized to the palindromes P8, P5 or P4. In the four cases with gain of PAR1, qPCR analysis showed duplicated signals for SRY and DDX3Y and one copy of IL9R, indicating isodicentric Yp chromosomes [idic(Y)] with breakpoint in Yq11.22. The two patients who had loss of PAR1, as shown by MLPA, had an additional reduction for SRY and DDX3Y, as shown by qPCR, associated with a high proportion of 45,X cells, as determined by FISH and karyotype. In agreement with the karyotype analysis, we detected DYZ3++ and DYZ3+ cells by FISH in the six patients, confirming idic(Y) and revealing additional monocentric Y chromosome [i(Y)]. Five patients had a history of major depressive disorders or bipolar disorder, and three had language impairment, whereas two patients showed severe short stature (Z score: -2.75 and -2.62), while a man with bipolar disorder was very tall (Z score: +2.56). LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: The number of males studied with Y-chromosome microdeletions and normozoospermic controls with normal karyotypes may not be enough to rule out an association between AZF deletions and PAR abnormalities. The prevalence of Y isochromosomes and/or 45,X cells detected in peripheral blood does not necessarily reflect the variations of PAR genes in target tissues. WIDER IMPLICATIONS OF THE FINDINGS: This study shows that CNVs in PARs were present exclusively in patients with terminal AZFb+c deletions associated with the presence of Y isochromosomes and 45,X cells, and may lead to neuropsychiatric and growth disorders. In contrast, we show that men with interstitial Yq microdeletions with normal karyotypes do not have an increased risk of PAR abnormalities and of phenotypical consequences. Moreover, our results highlight the importance of performing molecular studies, which are not considered in the usual screening for patients with Yq microdeletions. STUDY FUNDING/COMPETING INTERESTS: This work was supported by the National Fund for Scientific and Technological Development of Chile (FONDECYT), grant no. 1120176 (A.C.). The authors declare that no conflicting interests exist.


Assuntos
Cromossomos Humanos Y , Transtornos do Crescimento/psicologia , Isocromossomos , Transtornos Mentais/genética , Oligospermia/genética , Regiões Pseudoautossômicas/genética , Adolescente , Adulto , Estatura/genética , Deleção Cromossômica , Variações do Número de Cópias de DNA , Humanos , Masculino , Adulto Jovem
18.
Andrology ; 5(1): 41-48, 2017 01.
Artigo em Inglês | MEDLINE | ID: mdl-27769104

RESUMO

Several observational studies have showed a combination of lower testosterone (T) to LH ratio and higher estradiol (E2 ) to T ratio in secretory infertile men compared to men with normal spermatogenesis, suggesting a steroidogenic dysfunction of Leydig cells (Lc) that may involve increased aromatase activity. Low T/LH ratio is associated with Lc hyperplasia, which together with LH hyperstimulation may represent compensation for impaired T production. Aromatase expression and oestrogen production are mainly detected in Lc of the testis, although Sertoli and germ cells also contribute to testicular aromatase activity. The aim of this study was to assess the transcriptional expression of CYP19A1 (aromatase) in isolated Lc of subjects with Sertoli cell-only syndrome (SCOS) and signs of Lc impairment. Nineteen patients with SCOS and 10 controls with normal spermatogenesis who had medical indication of testicular biopsy for sperm retrieval were studied. Leydig cells were isolated by Laser Capture Microdissection (LCM) and CYP19A1 mRNA expression was quantified by SYBR® Green-based qPCR. In addition, testicular T and E2 and serum hormonal levels were measured. Relative to control group, CYP19A1 was overexpressed more than twofold in 10/19 cases (2.3-12.2-fold increase), showing a significant increment in cases with low T/LH ratio (T/LH < 2) compared to cases with T/LH ≥ 2 (p = 0.038, REST® ). Moreover, Rq data for CYP19A1 had a direct correlation with testicular levels of E2 and the E2 /T ratio (r = 0.869; p < 0.001 and r = 0.633; p = 0.005). In summary, Lc from infertile patients with signs of Lc dysfunction overexpressed aromatase and showed an increment of testicular E2 . Our results suggest that increased expression of aromatase in Lc leads to higher E2 production and may account for the functional impairment of the Lc in patients with SCOS.


Assuntos
Aromatase/genética , Células Intersticiais do Testículo/metabolismo , Síndrome de Células de Sertoli/genética , Testículo/metabolismo , Adulto , Aromatase/metabolismo , Estradiol/sangue , Hormônio Foliculoestimulante/sangue , Humanos , Microdissecção e Captura a Laser , Hormônio Luteinizante/sangue , Masculino , Síndrome de Células de Sertoli/metabolismo , Espermatogênese/genética , Testosterona/sangue
19.
Actas Urol Esp ; 41(2): 97-102, 2017 Mar.
Artigo em Inglês, Espanhol | MEDLINE | ID: mdl-27496771

RESUMO

OBJECTIVES: Animal models have shown that erectile dysfunction is associated with adipocyte accumulation under tunica albugínea, which could be involved in venous leakage and loss of penile rigidity. In the current sudy, we compared the histology of the penile sub-albuginean region of drug-refractory erectile dysfunction patients undergoing penile prosthesis implantation with potent patients with Peyronie's disease undergoing curvature correction procedures. MATERIALS AND METHODS: Seventeen refractory erectile dysfunction patients and fourteen potent patients with Peyronie's disease were recruited. Sub-albuginean tissue samples were taken in each surgery. An expert uropathologist analysed each section. A bivariate analysis was performed. Multivariate logistic regression was used to calculate adjusted odds ratios; P value<.05 was considered significant. RESULTS: Eleven patients (11/17) in the case group presented cavernous fat cell accumulation, while only one patient (1/14) in the control group presented this finding (P<.05). Adjusted odds ratio for erectile dysfunction was 40.72; 95% CI 2.28-727.29 (P=.012). CONCLUSIONS: Different studies have shown that androgen disruption could be involved in penile structural changes, leading to trabecular smooth muscle apoptosis and trans or de-differentiation into adipocytes. This is the first prospective study in humans to report an association between erectile dysfunction and sub-albuginean adipocyte accumulation. Venous leakage secondary to this phenomenon could be a factor in the pathophysiology of erectile dysfunction, especially in patients that do not respond to medical therapy.


Assuntos
Adipócitos , Disfunção Erétil/patologia , Disfunção Erétil/fisiopatologia , Pênis/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Induração Peniana/patologia , Estudos Prospectivos
20.
Rev. chil. enferm. respir ; 33(2): 131-136, 2017. graf
Artigo em Espanhol | LILACS | ID: biblio-1042617

RESUMO

Entre las variantes de la anatomía bronquial nos podemos encontrar con ramas bronquiales displásicas, ramas ausentes o ramas supernumerarias. Aunque gran parte son asintomáticas, es esencial reconocerlas porque se pueden asociar a hemoptisis, infecciones recurrentes, empiema o a complicaciones secundarias a procedimientos (por ejemplo intubaciones endotraqueales, fibrobroncoscopías, lavado broncoalveolar, biopsias, tratamientos endobronquiales, instalación de stent, braquiterapia y cirugías pulmonares entre otros). En este articulo describimos las variantes bronquiales más prevalentes en tomografia computada, incluyendo al bronquio cardíaco accesorio, bronquio traqueal y bronquio puente, entre otras.


Among the variations of bronchial anatomy, we can find dysplastic bronchial branches, an absence of bronchial branches, or supernumerary branches. Although many of them are asymptomatic, it is essential to know them because they may be associated with hemoptysis, recurrent infections, empyema, or complications secondary to various procedures (e.g. endotracheal intubation, brochoscopy, bronchoalveolar lavage, biopsy, endobronchial treatments, stent installation, brachytherapy and lung surgeries among others). In this study we used computed tomography to describe some of the most prevalent bronchial variations, including accessory cardiac bronchus, tracheal bronchus, and bridge bronchus among others.


Assuntos
Humanos , Brônquios/anormalidades , Brônquios/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Variação Anatômica
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