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1.
Cancers (Basel) ; 16(14)2024 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-39061175

RESUMEN

The prognosis for patients with metastatic castration-resistant prostate cancer (mCRPC) varies, being influenced by blood-related factors such as transcriptional profiling and immune cell ratios. We aimed to address the contribution of distinct whole blood immune cell components to the prognosis of these patients. This study analyzed pre-treatment blood samples from 152 chemotherapy-naive mCRPC patients participating in a phase 2 clinical trial (NCT02288936) and a validation cohort. We used CIBERSORT-X to quantify 22 immune cell types and assessed their prognostic significance using Kaplan-Meier and Cox regression analyses. Reduced CD8 T-cell proportions and elevated monocyte levels were substantially connected with a worse survival. High monocyte counts correlated with a median survival of 32.2 months versus 40.3 months for lower counts (HR: 1.96, 95% CI 1.11-3.45). Low CD8 T-cell levels were associated with a median survival of 31.8 months compared to 40.3 months for higher levels (HR: 1.97, 95% CI 1.11-3.5). These findings were consistent in both the trial and validation cohorts. Multivariate analysis further confirmed the independent prognostic value of CD8 T-cell counts. This study highlights the prognostic implications of specific blood immune cells, suggesting they could serve as biomarkers in mCRPC patient management and should be further explored in clinical trials.

2.
Cancers (Basel) ; 15(13)2023 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-37444524

RESUMEN

At present, the applications and efficacy of non-ionizing radiations (NIR) in oncotherapy are limited. In terms of potential combinations, the use of biocompatible magnetic nanoparticles as heat mediators has been extensively investigated. Nevertheless, developing more efficient heat nanomediators that may exhibit high specific absorption rates is still an unsolved problem. Our aim was to investigate if externally applied magnetic fields and a heat-inducing NIR affect tumor cell viability. To this end, under in vitro conditions, different human cancer cells (A2058 melanoma, AsPC1 pancreas carcinoma, MDA-MB-231 breast carcinoma) were treated with the combination of electromagnetic fields (EMFs, using solenoids) and hyperthermia (HT, using a thermostated bath). The effect of NIR was also studied in combination with standard chemotherapy and targeted therapy. An experimental device combining EMFs and high-intensity focused ultrasounds (HIFU)-induced HT was tested in vivo. EMFs (25 µT, 4 h) or HT (52 °C, 40 min) showed a limited effect on cancer cell viability in vitro. However, their combination decreased viability to approximately 16%, 50%, and 21% of control values in A2058, AsPC1, and MDA-MB-231 cells, respectively. Increased lysosomal permeability, release of cathepsins into the cytosol, and mitochondria-dependent activation of cell death are the underlying mechanisms. Cancer cells could be completely eliminated by combining EMFs, HT, and standard chemotherapy or EMFs, HT, and anti-Hsp70-targeted therapy. As a proof of concept, in vivo experiments performed in AsPC1 xenografts showed that a combination of EMFs, HIFU-induced HT, standard chemotherapy, and a lysosomal permeabilizer induces a complete cancer regression.

3.
Prostate ; 83(4): 376-384, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36564933

RESUMEN

BACKGROUND: There is a considerable need to incorporate biomarkers of resistance to new antiandrogen agents in the management of castration-resistant prostate cancer (CRPC). METHODS: We conducted a phase II trial of enzalutamide in first-line chemo-naïve asymptomatic or minimally symptomatic mCRPC and analyzed the prognostic value of TMPRSS2-ERG and other biomarkers, including circulating tumor cells (CTCs), androgen receptor splice variant (AR-V7) in CTCs and plasma Androgen Receptor copy number gain (AR-gain). These biomarkers were correlated with treatment response and survival outcomes and developed a clinical-molecular prognostic model using penalized cox-proportional hazard model. This model was validated in an independent cohort. RESULTS: Ninety-eight patients were included. TMPRSS2-ERG fusion gene was detected in 32 patients with no differences observed in efficacy outcomes. CTC detection was associated with worse outcome and AR-V7 in CTCs was associated with increased rate of progression as best response. Plasma AR gain was strongly associated with an adverse outcome, with worse median prostate specific antigen (PSA)-PFS (4.2 vs. 14.7 m; p < 0.0001), rad-PFS (4.5 vs. 27.6 m; p < 0.0001), and OS (12.7 vs. 38.1 m; p < 0.0001). The clinical prognostic model developed in PREVAIL was validated (C-Index 0.70) and the addition of plasma AR (C-Index 0.79; p < 0.001) increased its prognostic ability. We generated a parsimonious model including alkaline phosphatase (ALP); PSA and AR gain (C-index 0.78) that was validated in an independent cohort. CONCLUSIONS: TMPRSS2-ERG detection did not correlate with differential activity of enzalutamide in first-line mCRPC. However, we observed that CTCs and plasma AR gain were the most relevant biomarkers.


Asunto(s)
Células Neoplásicas Circulantes , Neoplasias de la Próstata Resistentes a la Castración , Humanos , Masculino , Biomarcadores de Tumor/genética , Células Neoplásicas Circulantes/patología , Nitrilos/uso terapéutico , Pronóstico , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/genética , Neoplasias de la Próstata Resistentes a la Castración/patología , Receptores Androgénicos/genética
4.
Sci Total Environ ; 851(Pt 2): 157999, 2022 Dec 10.
Artículo en Inglés | MEDLINE | ID: mdl-35988593

RESUMEN

Microplastics (MPs) can adsorb persistent organic pollutants such as oil hydrocarbons and may facilitate their transfer to organisms (Trojan horse effect). The aim of this study was to examine the effects of a 21 day dietary exposure to polystyrene MPs of 4.5 µm at 1000 particles/mL, alone and with sorbed oil compounds from the water accommodated fraction (WAF) of a naphthenic North Sea crude oil at two dilutions (25 % and 100 %), on marine mussels. An additional group of mussels was exposed to 25 % WAF for comparison. PAHs were accumulated in mussels exposed to WAF but not in those exposed to MPs with sorbed oil compounds from WAF (MPs-WAF), partly due to the low concentration of PAHs in the studied crude oil. Exposure to MPs or to WAF alone altered the activity of enzymes involved in aerobic (isocitrate dehydrogenase) and biotransformation metabolism (glutathione S-transferase). Prevalence of oocyte atresia and volume density of basophilic cells were higher and absorption efficiency lower in mussels exposed to MPs and to WAF than in controls. After 21 days MPs caused DNA damage (Comet assay) in mussel hemocytes. In conclusion, a Trojan horse effect was not observed but both MPs and oil WAF caused an array of deleterious effects on marine mussels at different levels of biological organization.


Asunto(s)
Mytilus , Petróleo , Contaminantes Químicos del Agua , Animales , Microplásticos , Petróleo/toxicidad , Petróleo/metabolismo , Plásticos/toxicidad , Plásticos/metabolismo , Poliestirenos/metabolismo , Agua/metabolismo , Contaminantes Orgánicos Persistentes , Mar del Norte , Isocitrato Deshidrogenasa/metabolismo , Isocitrato Deshidrogenasa/farmacología , Contaminantes Químicos del Agua/análisis , Glutatión Transferasa/metabolismo
5.
Sensors (Basel) ; 21(20)2021 Oct 13.
Artículo en Inglés | MEDLINE | ID: mdl-34695999

RESUMEN

Mobile robotic platforms have made inroads in the rehabilitation area as gait assistance devices. They have rarely been used for human gait monitoring and analysis. The integration of mobile robots in this field offers the potential to develop multiple medical applications and achieve new discoveries. This study proposes the use of a mobile robotic platform based on depth cameras to perform the analysis of human gait in practical scenarios. The aim is to prove the validity of this robot and its applicability in clinical settings. The mechanical and software design of the system is presented, as well as the design of the controllers of the lane-keeping, person-following, and servoing systems. The accuracy of the system for the evaluation of joint kinematics and the main gait descriptors was validated by comparison with a Vicon-certified system. Some tests were performed in practical scenarios, where the effectiveness of the lane-keeping algorithm was evaluated. Clinical tests with patients with multiple sclerosis gave an initial impression of the applicability of the instrument in patients with abnormal walking patterns. The results demonstrate that the system can perform gait analysis with high accuracy. In the curved sections of the paths, the knee joint is affected by occlusion and the deviation of the person in the camera reference system. This issue was greatly improved by adjusting the servoing system and the following distance. The control strategy of this robot was specifically designed for the analysis of human gait from the frontal part of the participant, which allows one to capture the gait properly and represents one of the major contributions of this study in clinical practice.


Asunto(s)
Trastornos Neurológicos de la Marcha , Procedimientos Quirúrgicos Robotizados , Robótica , Fenómenos Biomecánicos , Marcha , Análisis de la Marcha , Humanos , Caminata
6.
Rev. Fac. Med. Hum ; 21(4): 896-902, Oct.-Dic. 2021.
Artículo en Inglés, Español | LILACS-Express | LILACS | ID: biblio-1342256

RESUMEN

Las lesiones tumorales de localización parafaríngea presentan una escasa incidencia, representando entre el 0,5 y el 0,8% de todas las tumoraciones de cabeza y cuello. Aproximadamente el 80% presentan un comportamiento benigno. La singularidad de dichas lesiones deriva de su compleja situación anatómica y de la clínica con la que suelen debutar, siendo en la mayoría de los casos inespecífica y casi siempre derivada del efecto compresivo producido por la lesión sobre la oro y rinofaringe. Los Schwannoma del espacio parafaríngeo son tumores muy infrecuentes, que se originan de la vaina de schawnn, generalmente de crecimiento lento, suelen ser asintomáticos. El tratamiento es quirúrgico, muchas veces complejo por la localización anatómica. Se presenta el caso de una paciente femenina de 42 años de edad con diagnóstico de Schwannoma en la región parafaríngea izquierda demostrada mediante biopsia incisional; realizándosele tratamiento quirúrgico, el cual se llevó a cabo sin complicaciones.


Parapharyngeal tumor lesions present a low incidence, representing between 0,5 and 0,8% of all head and neck tumors. Approximately 80% show benign behavior. The uniqueness of these lesions derives from their complex anatomical situation and the symptoms with which they usually appear, being in most cases nonspecific and almost always derived from the compressive effect produced by the lesion on the oropharynx and the oropharynx. Schwannomas of the parapharyngeal space are very rare tumors that originate from the sheath of schawnn, generally slow growing, and are usually asymptomatic. Treatment is surgical, often complex due to the anatomical location. The case of a 42-year-old female patient with a diagnosis of Schwannoma in the left parapharyngeal region, demonstrated by incisional biopsy, is presented; undergoing surgical treatment, which was carried out without complications.

7.
Rev. Fac. Med. Hum ; 21(2): 445-448, Abr.-Jun. 2021.
Artículo en Inglés, Español | LILACS-Express | LILACS | ID: biblio-1179307

RESUMEN

Introducción: El neumomediastino es una patología poco frecuente y rara. Las manifestaciones radiológicas típicas en los pacientes en neumonía por SARS-CoV-2 consiste en la presencia de opacidades pulmonares bilaterales, de distribución periférica. En una reciente serie de pacientes con COVID-19 indica que el 1% de los pacientes pueden desarrollar neumomediastino espontáneo como complicación, generalmente es de curso benigno y no se aclara aún que ello puede suponer un indicador de agravamiento. Caso Clínico: Se trata de un paciente varón de 43 años que presentó un tiempo de enfermedad de 15 días caracterizado por dolor faríngeo, fiebre, dolor torácico y dificultad respiratoria, recibiendo múltiples esquemas de tratamiento tanto antiviral y antibióticos sin respuesta, por lo que acudió al Hospital Rebagliati donde se le encontró insuficiencia respiratoria, hipoxemia y sepsis. Su tomografía fue compatible con infiltrado en vidrio deslustrado, áreas de consolidación pulmonar bilateral y neumomediastino. No requirió tratamiento quirúrgico y evolucionó favorablemente a la neumonía con disminución de marcadores inflamatorios y remisión de neumomediastino en control tomográfico. Conclusión: Este reporte resalta que en la infección por COVID-19 las complicaciones pulmonares a tener en cuenta son la neumonía bilateral, coinfección bacteriana, sepsis y neumomediastino espontáneo.


Introduction: Pneumomediastinum is an infrequent and rare pathology. The typical radiological manifestations in patients with SARS-CoV-2 pneumonia consist of the presence of bilateral pulmonary opacities, of peripheral distribution. In a recent series of patients with COVID-19, it indicates that 1% of patients can develop spontaneous pneumomediastinum as a complication, it is generally benign and it is not yet clear that this may be an indicator of worsening. Clinical Case: This is a 43-year-old male patient who presented a 15-day illness characterized by pharyngeal pain, fever, chest pain and respiratory distress, receiving multiple antiviral and antibiotic treatment schemes without response, for which he attended to Rebagliati Hospital where he was found respiratory failure, hypoxemia and sepsis. His tomography was compatible with ground glass infiltrate, areas of bilateral lung consolidation, and pneumomediastinum. It did not require surgical treatment and it evolved favorably to pneumonia with a decrease in inflammatory markers and remission of pneumomediastinum in tomographic control. Conclusion: This report highlights that in COVID-19 infection the pulmonary complications to take into account are bilateral pneumonia, bacterial coinfection, sepsis and spontaneous pneumomediastinum.

8.
Rev. colomb. anestesiol ; 48(1): 12-19, Jan.-Mar. 2020. graf
Artículo en Inglés | LILACS, COLNAL | ID: biblio-1092915

RESUMEN

Abstract Introduction: In the age of healthcare safety, compliance with checklists and time tracking in surgery continue to be a gray zone in care processes. The technology applied to approach this issue and other scenarios, may contribute to solve a problem that impacts welfare and the healthcare sector economics. Objective: To introduce the design and construction of the MyCheckTime® software that incorporates Toyota's Lean methodology under the concept of Bundles. Materials and methods: Using a conceptual map, 5 measures were incorporated into the bundle; the MyCheckTime® platform was built based on a software code developed in Java8, PHP, Javascript, HTML5, Angular4, MongoDB-MySQL databases, and Docker, Ionic, VertX, Laravel-implemented technologies. Results: A software (MyCheckTime®) was constructed based on an App available for tablets and IOS and Android system-based mobile devices; a web-based platform and a database. The software captures the patient's circuit in the surgical area in real time, and records the times in which the checklists were conducted. Conclusion: MyCheckTime® is a Lean Methodology-based software that potentially enables the surgical team to deliver more efficient, safer, and timely care, allowing real time recording of the patient's circuit in the surgery area.


Resumen Introducción: En la era de la seguridad en la atención en salud, la de atención. La tecnología aplicada a esta problemática, al igual que adherencia a las listas de verificación y el seguimiento de tiempos otros escenarios, podrá contribuir a solucionar un problema que en el área de cirugía, continúan siendo puntos grises en los procesos de atención. La tecnología aplicada a esta problemática, al igual que otros escenarios, podrá contribuir a solucionar un problema que impacta el bienestar y la economía en el sector salud. Objetivo: Presentar el diseño y construcción del software MyCheckTime® que incorpora la metodología Lean de Toyota, bajo el concepto Bundles. Materiales y métodos: Mediante un mapa conceptual se incorporaron cinco medidas al paquete y se construyó una plataforma llamada MyCheckTime® con un código de software desarrollado en Java8, PHP, Javascript, HTML5, Angular4, bases de datos MongoDB-MySQL y tecnologías implementadas Docker, Ionic, VertX, Laravel. Resultados: Se construyó un software (MyCheckTime® ), compuesto por una App disponible para tabletas y móviles con sistema IOS o Android; una plataforma en la web y una base de datos. El software captura en tiempo real el circuito del paciente en el área de cirugía y registra los momentos en que se realizaron las listas de verificación. Conclusión: MyCheckTime® es un software basado en la Metodología Lean que potencialmente permitirá al equipo quirúrgico brindar una atención más eficiente, segura, y oportuna, permitiendo el registro en tiempo real del circuito que el paciente hace en el área de cirugía.


Asunto(s)
Humanos , Programas Informáticos , Cuidados Posteriores , Adaptabilidad , Atención a la Salud , Calidad de la Atención de Salud , Equipo Quirúrgico , Tecnología , Sector de Atención de Salud , Computadoras de Mano
9.
Sci Total Environ ; 692: 233-239, 2019 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-31349164

RESUMEN

Because of their biocide properties, silver nanoparticles (AgNPs) are present in numerous consumer products. The biocidal properties of AgNPs are due to both the interactions between AgNP and cell membranes and the release of dissolved silver (Ag+). Recent studies emphasized the role of different nanoparticle coatings in complexing and storing Ag+. In this study, the availability of dissolved silver in the presence of algae was assessed for three AgNPs with different silver contents (59%, 34% and 7% of total Ag), silver core sizes and casein shell thicknesses. The impact of ionic silver on the photosynthetic yield of Chlamydomonas reinhardtii was used as a proxy to estimate the amount of ionic silver toxically active during in vivo assays. The results showed that cysteine, a strong silver ligand, mitigated the toxicity of AgNPs in all cases, demonstrating the key role of Ag+ in this toxicity. The results showed that the AgNPs presenting an intermediate level of silver (34%) were 10 times more effective in terms of total mass (EC50 ten times smaller) than those presenting more (59%) or less (7%) silver. The higher toxicity was due to the higher release of Ag+ under biotic conditions due to the high surface/mass ratio of the nanoparticle silver core. Protein shells played a minor role in altering the availability of Ag+, probably acting as intermediate reservoirs. This study highlighted the utility of a very sensitive biological endpoint (i.e., algal photosynthesis) for the optimization of ionic silver delivery by nanomaterials.


Asunto(s)
Chlamydomonas reinhardtii/efectos de los fármacos , Nanopartículas del Metal/efectos adversos , Fotosíntesis/efectos de los fármacos , Plata/efectos adversos , Disponibilidad Biológica , Chlamydomonas reinhardtii/metabolismo , Cisteína/administración & dosificación , Relación Dosis-Respuesta a Droga , Iones/efectos adversos , Sustancias Protectoras/administración & dosificación
10.
Sensors (Basel) ; 19(11)2019 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-31141882

RESUMEN

This paper presents an approach to exploit the superimposed training (ST)-based primary users' (PUs) transmissions in the context of spectrum sensing for cognitive radio. In the low signal-to-noise ratio (SNR), the proposed scheme splits the spectrum sensing phase into two sample processing periods, allowing a secondary user (SU) to carry out a training sequence synchronization (with a small probability of error) before the implementation of a robust spectrum sensing algorithm that enhances the detection, based on the deterministic signal components embedded in the ST PU's signals along with the unknown data signal. The overall sensing performance is improved using a reasonable number of samples to achieve a high probability of detection, resulting in a reduced spectrum sensing duration. Furthermore, a low computational complexity version of the proposed ST combined approach for a reduced phase (SCAR-Phase) of spectrum sensing is presented, which attains the same detection performance with a smaller number of real operations in the low SNR. In the practical consideration of imperfect training sequence synchronizations, the results show the advantages of exploiting the ST sequence to perform spectrum sensing, thus quantifying the significant improvement in detection performance and the maximum SU's achievable throughput.

11.
Case Rep Rheumatol ; 2017: 9407675, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28386506

RESUMEN

Granulomatosis with polyangiitis (GPA) is a systemic necrotizing granulomatosis vasculitis characterized by predilection to affect small- and medium-sized blood vessels and commonly affects the upper and lower respiratory tract and kidneys in most cases. Genital involvement is reported in <1% of cases in large cohorts and nearly all cases have been in the setting of multisystemic disease or during the course of the disease in patients already diagnosed as GPA. A case is presented of uncommon limited urogenital GPA in a 66-year-old woman with an irregular mass occupying urethra and vagina. The patient showed a good response after Corticoids and Methotrexate.

12.
J Med Case Rep ; 9: 206, 2015 Sep 11.
Artículo en Inglés | MEDLINE | ID: mdl-26361972

RESUMEN

INTRODUCTION: Very few cases of scar sarcoidosis affecting the eyes and bone together have been reported in the last few years. CASE PRESENTATION: We report a case of a 49-year-old Spanish man with recurrent bilateral granulomatous uveitis and a fistulous nodular lesion in the left pre-tibial region (scar granuloma) on the site of an 8-year-old scar. He presented with bilateral hilar adenopathies and elevation of inflammatory markers and angiotensin-converting enzyme. A histologically confirmed sarcoid of the tibia with a radiologic appearance unusual for long tubular bone involvement was observed. He also had bilateral ophthalmologic involvement. CONCLUSIONS: Sarcoidosis is a disease of unknown cause histologically characterized by non-caseating granulomas that can involve any organ or tissue. Osseous sarcoidosis is a relatively rare presentation. However, on the basis of cases reported in the literature, sarcoid lesions on bones are generally asymptomatic. Biologic agents are considered an alternative therapy for sarcoidosis resistant to conventional treatment.


Asunto(s)
Granuloma/complicaciones , Extremidad Inferior/diagnóstico por imagen , Sarcoidosis/complicaciones , Uveítis/complicaciones , Corticoesteroides/uso terapéutico , Antibacterianos/uso terapéutico , Cicatriz/complicaciones , Cicatriz/diagnóstico por imagen , Cicatriz/tratamiento farmacológico , Diagnóstico Diferencial , Granuloma/diagnóstico por imagen , Granuloma/tratamiento farmacológico , Humanos , Inmunosupresores/uso terapéutico , Masculino , Metotrexato/uso terapéutico , Persona de Mediana Edad , Prednisona/uso terapéutico , Radiografía , Sarcoidosis/diagnóstico por imagen , Sarcoidosis/tratamiento farmacológico , Tibia/diagnóstico por imagen , Uveítis/diagnóstico por imagen , Uveítis/tratamiento farmacológico
13.
Environ Sci Technol ; 49(13): 8041-7, 2015 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-26018638

RESUMEN

Various factors have been invoked to explain the toxicity of silver nanoparticles (AgNP) to microorganisms including particle size and the nature of stabilizing coatings as well as the amount of dissolved silver occurring in AgNP suspensions. In this study we have assessed the effects of nine differently coated AgNP (chitosan, lactate, polyvinylpyrrolidone, polyethelene glycol, gelatin, sodium dodecylbenzenesulfonate, citrate, dexpanthenol, and carbonate) and AgNO3 on the photosynthesis of the freshwater algae Chlamydomonas reinhardtii. We have thus examined how AgNP effects on algae relate to particle size, measured dissolved silver (Agd), and bioavailable silver (Agbioav). Agbioav was indirectly estimated in toxicity experiments by cysteine-silver complexation at the EC50. The EC50 calculated as a function of measured Agd concentrations showed for some coatings values similar to that of dissolved Ag, whereas other coated AgNP displayed lower EC50 values. In all cases, excess cysteine completely prevented effects on photosynthetic yield, confirming the role of Agd as a cause of the observed effect on the photosynthesis. Toxicity was related neither to particle size nor to the coatings. For all differently coated AgNP suspensions, the EC50 values calculated as a function of Agbioav were comparable to the value of AgNO3. Depending on the coatings Agbioav was comparable to or higher than measured Agd.


Asunto(s)
Chlamydomonas reinhardtii/efectos de los fármacos , Nanopartículas del Metal/química , Nanopartículas del Metal/toxicidad , Fotosíntesis/efectos de los fármacos , Plata/toxicidad , Bencenosulfonatos/química , Bencenosulfonatos/toxicidad , Carbonatos/química , Carbonatos/toxicidad , Quitosano/química , Quitosano/toxicidad , Chlamydomonas reinhardtii/fisiología , Citratos/química , Citratos/toxicidad , Cisteína/farmacología , Cisteína/toxicidad , Gelatina/química , Gelatina/toxicidad , Lactatos/química , Lactatos/toxicidad , Ácido Pantoténico/análogos & derivados , Ácido Pantoténico/química , Ácido Pantoténico/toxicidad , Tamaño de la Partícula , Polietilenglicoles/química , Polietilenglicoles/toxicidad , Povidona/toxicidad , Plata/farmacocinética , Nitrato de Plata/farmacocinética , Pruebas de Toxicidad/métodos
14.
Rev. biol. trop ; Rev. biol. trop;62(2): 611-625, Jun.-Aug. 2014. ilus, tab
Artículo en Español | LILACS | ID: lil-715456

RESUMEN

Gobiidae is the most specious fish family in the world with almost 2 000 species, however only 11% of them have been described for their larval stages. The entire life cycle information is essential to understand the biology and ecology of this important fish group. Previous studies on zooplankton samples from Ensenada de La Paz, México, have shown the presence of several Gobiidae larvae and juveniles which were identified as Evermania zosterura. The main objective of this work was to describe the larval stages of this species, widely distributed in the Eastern tropical Pacific. The development of E. zosterura larvae was described based on 66 specimens. A total of 53 specimens were used to describe morphometrics and pigmentation patterns, while 13 specimens were cleared and stained, to obtain meristic characteristics. Cleared specimens had 30 to 31 total vertebrae; dorsal-fin elements: IV; I, 13-14, anal-fin elements: I, 13-14, and most had pterygiophore formula 4-111100. The combination of these characteristics confirmed these specimens as E. zosterura. The pigment pattern is similar throughout ontogeny. Larvae are characterized by having three to five dendritic melanophores along the post-anal ventral margin, four to nine smaller melanophores along the ventral margin between the isthmus and anus, and one on the midpoint of the dorsal margin of the tail. There is one small pigment spot on the angle of the jaw, and other on the tip of lower lip. There is an elongated internal pigment under the notochord, between the head and gas bladder. Notochord flexion starts near 3.5mm BL and ends at 4.6mm BL; transformation to the juvenile stage is at about 13.6mm BL. Our conclusion is that the most useful characters to distinguish this species early-larval stages from those of similar species in the area, are the number of myomeres, the large melanophores (approximately uniformly in size) on the post anal ventral margin, and the elongate internal pigment under the notochord, anterior to the gas bladder. Rev. Biol. Trop. 62 (2): 603-610. Epub 2014 June 01.


La familia Gobiidae es la más diversa de los peces en el mundo con casi 2 000 especies, sin embargo solo el 11% de ellos han sido descritos en sus estadios larvarios. El conocimiento del ciclo de vida completo es esencial para entender la biología y ecología de este importante grupo de peces. Muestras de zooplancton obtenidas de la Ensenada de La Paz, México, mostraron la presencia de varias larvas y juveniles de Gobiidae, las cuales fueron identificadas como Evermania zosterura. El principal objetivo de este trabajo fue describir los estadios larvarios de esta especie ampliamente distribuida en el Pacífico tropical Oriental. Se describió el desarrollo larvario de E. zosterura con base en 66 especímenes recolectados en la Ensenada de La Paz, México. Sólo 53 especímenes se usaron para describir la morfometría y el patrón de pigmentación, mientras que 13 ejemplares transparentados y teñidos se utilizaron para obtener las características merísticas. Los especímenes transparentados tuvieron de 30 a 31 vertebras totales; los elementos de las aletas dorsales fueron IV; I, 13-14, los de la aleta anal I, 13-14 y la mayoría tuvo una formula pterigiofórica de 4-111100. La combinación de estas características, confirmó que pertenecen a E. zosterura. El patrón de pigmentación es muy similar a lo largo del desarrollo. Las larvas se caracterizan por tener de tres a cinco melanóforos de tipo dendrítico sobre el borde ventral post-anal, de cuatro a nueve melanóforos más pequeños sobre el borde ventral pre-anal, entre el istmo y el ano, otro melanóforo se presenta a la mitad del margen dorsal de la cola. Hay una pequeña mancha de pigmento en el ángulo de la maxila y otra en la punta del labio inferior. Hay un pigmento interno alargado por debajo de la notocorda, entre la cabeza y la vejiga natatoria. La flexión de la notocorda se inicia a los 3.5mm BL y termina a los 4.6mm BL; la transformación al estadio juvenil es cercana a los 13.6mm BL. Nuestra conclusión es que los caracteres más importantes para distinguir las larvas de esta especie de aquellas similares en el área son el número de miómeros, los melanóforos grandes (aproximadamente iguales en tamaño) en el margen ventral post-anal y el pigmento interno alargado debajo de la notocorda, anterior a la vejiga gaseosa.


Asunto(s)
Animales , Femenino , Masculino , Perciformes/crecimiento & desarrollo , Larva/crecimiento & desarrollo , México , Pigmentación , Perciformes/anatomía & histología , Perciformes/clasificación
15.
J Photochem Photobiol B ; 132: 94-101, 2014 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-24607609

RESUMEN

Although the biological importance of ultraviolet light (UVR) attenuation has been recognised in marine and freshwater environments, it is not generally considered in in vitro ecotoxicological studies using algal cell suspensions. In this study, UVA and UVB extinction were determined for cultures of algae with varying cell densities, and the data were used to calculate the corresponding extinction coefficients for both UVA and UVB wavelength ranges. Integrating the Beer-Lambert equation to account for changes in the radiation intensity reaching each depth, from the surface until the bottom of the experimental vessel, we obtained the average UVA and UVB intensity to which the cultured algal cells were exposed. We found that UVR intensity measured at the surface of Chlamydomonas reinhardtii cultures lead to a overestimation of the UVR dose received by the algae by 2-40 times. The approach used in this study allowed for a more accurate estimation of UVA and UVB doses.


Asunto(s)
Chlamydomonas/efectos de la radiación , Rayos Ultravioleta , Chlamydomonas/citología , Relación Dosis-Respuesta en la Radiación , Cinética , Modelos Biológicos
16.
BMJ Open ; 3(12): e003836, 2013 Dec 30.
Artículo en Inglés | MEDLINE | ID: mdl-24381254

RESUMEN

OBJECTIVES: We performed a re-analysis of the data from Navarro et al (2003) in which health symptoms related to microwave exposure from mobile phone base stations (BSs) were explored, including data obtained in a retrospective inquiry about fear of exposure from BSs. DESIGN: Cross-sectional study. SETTING: La Ñora (Murcia), Spain. PARTICIPANTS: Participants with known illness in 2003 were subsequently disregarded: 88 participants instead of 101 (in 2003) were analysed. Since weather circumstances can influence exposure, we restricted data to measurements made under similar weather conditions. OUTCOMES AND METHODS: A statistical method indifferent to the assumption of normality was employed: namely, binary logistic regression for modelling a binary response (eg, suffering fatigue (1) or not (0)), and so exposure was introduced as a predictor variable. This analysis was carried out on a regular basis and bootstrapping (95% percentile method) was used to provide more accurate CIs. RESULTS: The symptoms most related to exposure were lack of appetite (OR=1.58, 95% CI 1.23 to 2.03); lack of concentration (OR=1.54, 95% CI 1.25 to 1.89); irritability (OR=1.51, 95% CI 1.23 to 1.85); and trouble sleeping (OR=1.49, 95% CI 1.20 to 1.84). Changes in -2 log likelihood showed similar results. Concerns about the BSs were strongly related with trouble sleeping (OR =3.12, 95% CI 1.10 to 8.86). The exposure variable remained statistically significant in the multivariate analysis. The bootstrapped values were similar to asymptotic CIs. CONCLUSIONS: This study confirms our preliminary results. We observed that the incidence of most of the symptoms was related to exposure levels-independently of the demographic variables and some possible risk factors. Concerns about adverse effects from exposure, despite being strongly related with sleep disturbances, do not influence the direct association between exposure and sleep.

17.
Environ Toxicol Chem ; 28(10): 2108-16, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19432503

RESUMEN

The aim of the present study was to investigate the kinetics of cadmium (Cd) accumulation (total and intracellular) in periphyton under freshwater conditions in a short-term microcosm experiment. Periphyton was precolonized in artificial flow-through channels supplied with natural freshwater and then exposed for 26.4 h to nominal Cd concentrations of 5 and 20 nM added to natural freshwater. Labile Cd in water determined with diffusion gradient in thin films was 60 to 69% of total dissolved Cd in the exposure channels and 11% in the control channel. Intracellular Cd concentrations in periphyton increased rapidly and linearly during the first 71 min. Initial intracellular uptake rates were 0.05 and 0.18 nmol of Cd/g of dry weight x min in the 5 nM and 20 nM exposures, respectively. The subsequent intracellular uptake was slower, approaching steady state at the end of Cd exposure. Uptake kinetics of Cd was slower when compared to experiments with planktonic algal cultures, probably due to diffusion limitations. Intracellular Cd uptake during the entire exposure was modeled with a nonlinear, one-compartment model from which uptake and clearance rate constants, as well as bioconcentration factors, were obtained. The release of Cd from periphyton after the end of Cd exposure was slow when compared to the initial uptake rates.


Asunto(s)
Cadmio/metabolismo , Eucariontes/metabolismo , Agua Dulce , Contaminantes Químicos del Agua/metabolismo , Cadmio/análisis , Cadmio/farmacocinética , Cinética , Factores de Tiempo , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/farmacocinética
18.
Environ Sci Technol ; 42(23): 8959-64, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-19192825

RESUMEN

Silver nanoparticles (AgNP) are likely to enter the aquatic environment because of their multiple uses. We have examined the short-term toxicity of AgNP and ionic silver (Ag+) to photosynthesis in Chlamydomonas reinhardtii using fluorometry. AgNP ranged in size from 10 to 200 nm with most particles around 25 nm. As determined by DGT (diffusive gradients in thin films), by ion-selective electrode, and by centrifugal ulrafiltration, about 1% of the AgNP was present as Ag+ ions. Based on total Ag concentration, toxicity was 18 times higher for AgNO3 than for AgNP (in terms of EC50). However, when compared as a function of the Ag+ concentration,toxicity of AgNP appeared to be much higher than that of AgNO3. The ionic Ag+ measured in the AgNP suspensions could not fully explain the observed toxicity. Cysteine, a strong Ag+ ligand, abolished the inhibitory effects on photosynthesis of both AgNP and Ag+. Together, the results indicate that the interaction of these particles with algae influences the toxicity of AgNP, which is mediated by Ag+. Particles contributed to the toxicity as a source of Ag+ which is formed in presence of algae.


Asunto(s)
Chlamydomonas reinhardtii/efectos de los fármacos , Nanopartículas/toxicidad , Plata/toxicidad , Pruebas de Toxicidad , Animales , Cisteína/farmacología , Nanopartículas/ultraestructura , Fotosíntesis/efectos de los fármacos , Plata/análisis , Nitrato de Plata/toxicidad
20.
Rev. biol. trop ; Rev. biol. trop;51(2): 479-487, jun. 2003. ilus, tab
Artículo en Inglés | LILACS | ID: lil-365940

RESUMEN

The development of Diapterus peruvianus (Sauvage 1879) is based on 60 larvae collected in superficial tows made in Bahía Concepción, and on 16 pre-juvenile and juvenile organisms collected in Bahía de La Paz, B. C. S., México, using a standard plankton net and a rectangular epibenthonic net, respectively. Larvae of D. peruvianus show three large blotches on the dorsum of the gut that can fuse together and give the appearance of one large continuous blotch. There are two to three pre-anal pigments and 16 post-anal pigments in the ventral midline; cephalic pigments are present from the postflexion stage, as well as a serrated preoperculum. The pre-juvenile and juvenile organisms are distinguished by their body depth, the anal-fin formula, the serrated pre-operculum and the base pigments in the dorsal and anal fins.


Asunto(s)
Animales , Estadios del Ciclo de Vida , Perciformes , México , Perciformes
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