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During the East Antarctic International Ice Sheet Traverse (Eaiist, december 2019), in an unexplored part of the East Antarctic Plateau, snow samples were collected to expand our knowledge of the latitudinal variability of iodine, bromine and sodium as well as their relation in connection with emission processes and photochemical activation in this unexplored area. A total of 32 surface (0-5 cm) and 32 bulk (average of 1 m depth) samples were taken and analysed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Our results show that there is no relevant latitudinal trend for bromine and sodium. For bromine they also show that it has no significant post-depositional mechanisms while its inland surface snow concentration is influenced by spring coastal bromine explosions. Iodine concentrations are several orders of magnitude lower than bromine and sodium and they show a decreasing trend in the surface samples concentration moving southward. This suggests that other processes affect its accumulation in surface snow, probably related to the radial reduction in the ozone layer moving towards central Antarctica. Even though all iodine, bromine and sodium present similar long-range transport from the dominant coastal Antarctic sources, the annual seasonal cycle of the ozone hole over Antarctica increases the amount of UV radiation (in the 280-320 nm range) reaching the surface, thereby affecting the surface snow photoactivation of iodine. A comparison between the bulk and surface samples supports the conclusion that iodine undergoes spring and summer snow recycling that increases its atmospheric lifetime, while it tends to accumulate during the winter months when photochemistry ceases.
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Yodo , Bromo , Nieve , Sodio , Regiones AntárticasRESUMEN
Pigs are faced with various perturbations throughout their lives, some of which are induced by management practices, others by natural causes. Resilience is described as the ability to recover from or cope with a perturbation. Using these data, activity patterns of an individual, as well as deviations from these patterns, can potentially be used to quantify resilience. Dynamic indicators of resilience (DIORs) may measure resilience on a different dimension by calculating variation, autocorrelation and skewness of activity from the absolute activity data. The aim of this study was to investigate the potential of using DIORs of activity, such as average, root mean square error (RMSE), autocorrelation or skewness as indicators of resilience to infection with the Porcine Reproductive and Respiratory Syndrome Virus (PRRSV). For this study, individual activity was obtained from 232 pigs equipped with ear tag accelerometers and inoculated with PRRSV between seven and 9 weeks of age. Clinical scores were assigned to each individual at 13 days post-challenge and used to distinguish between a resilient and non-resilient group. Mortality post-challenge was also recorded. Average, RMSE, autocorrelation and skewness of activity were calculated for the pre- and post-challenge phases, as well as the change in activity level pre- vs. post-challenge (i.e., delta). DIORs pre-challenge were expected to predict resilience to PRRSV in the absence of PRRSV infection, whereas DIORs post-challenge and delta were expected to reflect the effect of the PRRSV challenge. None of the pre-challenge DIORs predicted morbidity or mortality post-challenge. However, a higher RMSE in the 3 days post-challenge and larger change in level and RMSE of activity from pre- to post-challenge tended to increase the probability of clinical signs at day 13 post-infection (poor resilience). A higher skewness post-challenge (tendency) and a larger change in skewness from pre- to post-challenge increased the probability of mortality. A decrease in skewness post-challenge lowered the risk of mortality. The post-challenge DIOR autocorrelation was neither linked to morbidity nor to mortality. In conclusion, results from this study showed that post-challenge DIORs of activity can be used to quantify resilience to PRRSV challenge.
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Chronic postsurgical pain (CPSP) is a common postoperative adverse event affecting up to half of women undergoing breast cancer surgery, yet few epidemiological studies have prospectively investigated the role of preoperative, intraoperative, and postoperative risk factors for pain onset and chronicity. We prospectively investigated preoperative sociodemographic and psychological factors, intraoperative clinical factors, and acute postoperative pain in a prospective cohort of 362 women undergoing surgery for primary breast cancer. Intraoperative nerve handling (division or preservation) of the intercostobrachial nerve was recorded. At 4 and 9months after surgery, incidence of chronic painful symptoms not present preoperatively was 68% and 63%, respectively. Univariate analysis revealed that multiple psychological factors and nerve division was associated with chronic pain at 4 and 9months. In a multivariate model, independent predictors of CPSP at 4months included younger age and acute postoperative pain (odds ratio [OR] 1.34, 95% confidence interval [CI] 1.12 to 1.60), whereas preoperative psychological robustness (OR 0.70, 95% CI 0.49 to 0.99), a composite variable comprising high dispositional optimism, high positive affect, and low emotional distress, was protective. At 9months, younger age, axillary node clearance (OR 2.97, 95% CI 1.09 to 8.06), and severity of acute postoperative pain (OR 1.17, 95% CI 1.00 to 1.37) were predictive of pain persistence. Of those with CPSP, 25% experienced moderate to severe pain and 40% were positive on Douleur Neuropathique 4 and Self-Complete Leeds Assessment of Neuropathic Symptoms and Signs pain scales. Overall, a high proportion of women report painful symptoms, altered sensations, and numbness in the upper body within the first 9months after resectional breast surgery and cancer treatment.
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Neoplasias de la Mama/psicología , Neoplasias de la Mama/cirugía , Dimensión del Dolor/psicología , Dolor Postoperatorio/psicología , Vigilancia de la Población , Factores de Edad , Anciano , Neoplasias de la Mama/epidemiología , Estudios de Cohortes , Femenino , Humanos , Persona de Mediana Edad , Dimensión del Dolor/métodos , Dolor Postoperatorio/diagnóstico , Dolor Postoperatorio/epidemiología , Vigilancia de la Población/métodos , Valor Predictivo de las Pruebas , Estudios Prospectivos , Factores Socioeconómicos , Resultado del TratamientoRESUMEN
Domoic acid (DA) is a neurotoxin produced by different algae, including pennate diatoms, principally from the genus Pseudo-nitzschia, and it is the main cause of amnesic shellfish poisoning. Determination of this toxin in seawater samples is fundamental to define the real contamination risks for aquatic species. We have developed two very sensitive instrumental methods using hydrophilic interaction liquid chromatography coupled using tandem mass spectrometry in positive and negative polarity modes. Instrumental detection limits were 9 pg mL(-1) for positive and 19 pg mL(-1) for negative ionisation. A procedural method based on solid-phase extraction for the determination of dissolved DA present in seawater has been developed, and an extraction procedure was employed for the determination of the toxin in the particulate fraction. DA quantification was performed using the internal standard method to account for signals fluctuations and random errors during sample treatment. To our knowledge, this is the first study to use this quantification method for DA determination. Trueness, extraction yield, matrix effects, repeatability and procedural detection limits were evaluated during method validation. Procedural detection limits of 0.3 pg mL(-1) (positive mode) and 0.6 pg mL(-1) (negative mode) were found for the dissolved fraction, and absolute limits of 0.4 pg (positive mode) and 6.0 pg (negative mode) for particulate samples were obtained. The most sensitive method in positive mode was applied to define DA occurrence in the Venice Lagoon. Trace concentrations of domoic acid ranging from 1.5 to 16.2 pg mL(-1) were found for the first time in the Venetian environment.
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Cromatografía Líquida de Alta Presión/métodos , Ácido Kaínico/análogos & derivados , Toxinas Marinas/análisis , Agua de Mar/análisis , Espectrometría de Masas en Tándem/métodos , Cromatografía Líquida de Alta Presión/normas , Ácido Kaínico/análisis , Estándares de Referencia , Espectrometría de Masas en Tándem/normasRESUMEN
The direct influence of ship traffic on atmospheric levels of coarse and fine particulate matter (PM(2.5), PM(10)) and fifteen polycyclic aromatic hydrocarbons (PAHs) has been estimated in the urban area of Venice. Data analysis has been performed on results collected at three sites over the summer, when ship traffic is at a maximum. Results indicate that monitoring of the PM daily concentrations is not sufficiently detailed for the evaluation of this contribution, even though it could be useful for specific markers such as PAHs. Therefore a new methodology, based on high temporal resolution measurements coupled with wind direction information and the database of ship passages of the Harbour Authority of Venice has been developed. The sampling sites were monitored with optical detectors (DustTrack(®) and Mie pDR-1200) operating at a high temporal resolution (20s and 1s respectively) for PM(2.5) and PM(10). PAH in the particulate and gas phases were recovered from quartz fibre filters and polyurethane foam plugs using pressurised solvent extraction, the extracts were then analysed by gas chromatography- high-resolution mass spectrometry. Our results shows that the direct contribution of ships traffic to PAHs in the gas phase is 10% while the contribution to PM(2.5) and to PM(10) is from 1% up to 8%.
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Contaminantes Atmosféricos/análisis , Monitoreo del Ambiente/métodos , Material Particulado/análisis , Hidrocarburos Policíclicos Aromáticos/análisis , Navíos , Emisiones de Vehículos/análisis , Italia , Estaciones del Año , VientoRESUMEN
In the history of art, artists have used many different organic compounds to dissolve pigments and apply them onto a support to obtain a paint layer. Proteins were used with success from the Middle Ages up to the Renaissance, and the traditional protein sources were animal parts (skins, tendons and bones) or milk and eggs. Moreover, some of these materials are commonly used as adhesive. In this paper, the first application of the metallomic analytical technique to the identification of proteins in artworks is reported. Samples were derivatized with DTPA/Eu and the derivatization procedure was evaluated by matrix-assisted laser desorption/ionization time-of-flight before high performance liquid chromatography inductively coupled plasma MS analysis. This study has been carried out on laboratory models prepared in-house for method development, resulting in the correct identification of the different classes of proteinaceous binders typically used. In addition, some unknown paint layer samples have been analyzed demonstrating that the method is applicable to very small sample amounts (0.6 mg), which are compatible with the amount normally available for this kind of analysis. The results obtained demonstrate the effectiveness of the method, suggesting the potential future use as novel diagnostic tool in the scientific study of artworks.
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Inks and paper are the main materials and components of library and archive collections. Since the beginning of paper and ink production empirical recipes have been followed, but in the 19th century with the transformation of Europe during the Industrial Revolution, the continent became the main leader for the discovery of new products and new industrial production processes. The aim of this study is to shed light on paper and ink production processes during this key historical period. In this study we have chosen some documents preserved in the archive of the Soprintendenza dei Beni Architettonici e Paesaggistici (B.A.P.) di Venezia e Laguna, held in the Palazzo Ducale (Ducal Palace) of Venice. Attenuated total reflection Fourier transform infrared spectroscopy (ATR-FT-IR), and inductively coupled plasma-mass spectrometry (ICP-MS) allowed us to obtain a qualitative and quantitative characterization of the organic and inorganic components in both paper and inks. Cluster analysis and principal component analysis (PCA) were employed for statistical analysis of the results.
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In this paper, the effect of sonication on the UV disinfection kinetics of primary effluents was investigated. Wastewater samples were collected from local municipal treatment plants and were sonicated with a 20-kHz ultrasound reactor at constant power but varying sonication times. Sonicated samples were irradiated using low-pressure UV light to obtain the UV dose-response curves (DRC). Results showed that sonication improved the UV disinfection of primary effluents by (1) increasing the initial slope of DRC (i.e., k1) and (2) decreasing the tailing level of the UV dose-response curve (i.e., beta). This improvement was confirmed to be caused by the breakage of large particles (> 60 microm) that are known to protect coliforms from UV photons. It also was found that the log reduction of the tailing level of DRC was directly proportional to the log reduction of the number of large particles (> 60 microm) present in the effluent sample. Although the number of large particles was proportional to the coliform count at high UV dosage, the proportionality constant varied from 0.05 to 0.25, depending on the sample.
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Desinfección/métodos , Sonicación , Rayos Ultravioleta , Purificación del Agua/métodos , Residuos Industriales , Cinética , Tamaño de la PartículaRESUMEN
1. The purpose of this study was to evaluate the role of coding variation in hPXR (NR1I2) in intrahepatic cholestasis of pregnancy (ICP) and to functionally asses the response of PXR variants to ligands of interest in ICP. 2. The coding region of hPXR was sequenced in a cohort of 121 Caucasian ICP patients and exon 2 was sequenced in an additional 226 cases. Reporter assays were used to evaluate the function of all known hPXR variants in response to the secondary bile acid lithocholic acid and therapeutic agents rifampicin, ursodeoxycholic acid and dexamethasone. 3. Two coding single nucleotide polymorphisms (C79T and G106A) were detected in the ICP cohort at frequencies consistent with healthy populations. These do not alter hPXR function in response to ligands of interest to ICP. Analysis of all known coding hPXR variants demonstrates that while subtle changes in experimental design mask or may unveil the functional effects of genetic variation, these are not maintained in a standard functional assay. 4. Coding genetic variation in hPXR does not contribute to the aetiology of ICP in Caucasian populations.
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Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Complicaciones del Embarazo/genética , Receptores de Esteroides/genética , Secuencia de Bases , Femenino , Humanos , Datos de Secuencia Molecular , Embarazo , Receptor X de PregnanoRESUMEN
A method based on the coupling of HPLC with ICP-MS with an on-line pre-concentration micro-column has been developed for the analysis of inorganic and methyl mercury in the dissolved phase of natural waters. This method allows the rapid pre-concentration and matrix removal of interferences in complex matrices such as seawater with minimal sampling handling. Detection limits of 0.07 ng L(-1) for inorganic mercury and 0.02 ng L(-1) for methyl mercury have been achieved allowing the determination of inorganic mercury and methyl mercury in filtered seawater from the Venice lagoon. Good accuracy and reproducibility was demonstrated by the repeat analysis of the certified reference material BCR-579 coastal seawater. The developed HPLC separation was shown to be also suitable for the determination of methyl mercury in extracts of the particulate phase.
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BACKGROUND: Student selected components (SSCs) represent a significant component of medical curricula in the UK and a new approach in medical education. Despite the prominence given to SSCs by the General Medical Council in each of its seminal papers regarding undergraduate medical education, there remains a diverse view of the purpose, outcomes, structure and assessment of SSCs. Many Schools have adopted their own perspective of SSCs and created different but often innovative courses. AIMS: This article brings together the Scottish Medical Schools and their experience in organising SSCs, highlights some of the challenges and offers possible solutions to some of the difficulties encountered. METHOD: The SSC Director from each of the Scottish medical schools each contributed their own '12 Tips'. From these a consensus was achieved. RESULTS: Even though the Scottish medical schools have a wide range of curriculum and timetable formats, there was a great deal of agreement in the challenges and problems encountered in their SSC programmes, as expressed through these 12 Tips. CONCLUSION: There is much diversity in SSC programmes at different medical schools, although there is also much commonality in the challenges that arise. We hope that this paper will promote thought and discussion amongst those involved, and be useful to those involved in curriculum and programme development and also to those new to medical education.
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Conducta de Elección , Curriculum , Educación de Pregrado en Medicina/organización & administración , Estudiantes de Medicina , Consenso , Guías como Asunto , Humanos , EscociaRESUMEN
BACKGROUND: Palliative care strives to offer patients and their families choice in the location of their management and final terminal care. The place of death has been shown to be related to various patient, carer and health service factors. AIM: This study explores place of death of palliative care patients in regional north Queensland, and investigates which patient, disease, and other factors impact on place of death. METHODS: All patients under the care of the specialist Palliative Care Service (PCS) at The Townsville Hospital, who died in 2004, were identified. Medical charts for these patients were analysed for various demographic data, disease-related information and place of death. RESULTS: Some 270 patients were analysed. A total of 162 were male, median age was 72 years, and 146 (54%) were married. Home death rate was 19% (54 patients), with 64% (173) of patients dying in hospital. Factors significantly associated with home death included younger age, married, a diagnosis of colorectal carcinoma, and the involvement of community nurses. There was a trend towards male patients being more likely to die at home. Logistic regression analysis indicated that younger age and community nurse involvement were significantly associated with home death. DISCUSSION: The results of this study are in keeping with available, largely urban-based literature, with respect to predictive factors of home death. Further prospective study, with an emphasis on choice regarding place of care and GP involvement with palliative care patients, is warranted.
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Actitud Frente a la Muerte , Servicios de Atención de Salud a Domicilio/estadística & datos numéricos , Hospitalización/estadística & datos numéricos , Cuidados Paliativos/psicología , Factores de Edad , Anciano , Femenino , Humanos , Masculino , Estado Civil , Persona de Mediana Edad , Cuidados Paliativos/estadística & datos numéricos , Queensland , Estudios RetrospectivosRESUMEN
INTRODUCTION: Rural patients have poor outcomes in cancer management. Previous studies have shown different health beliefs and values in rural populations with high levels of stoicism and fatalism, leading to later presentation and diagnosis, with subsequent poorer prognosis and survival. This study explores the relationship between urban or rural background and health attitudes of newly diagnosed oncology patients, attending one oncology unit in north Queensland, during a 5 month period. This study is a forerunner to a planned larger project to explore the research question: do oncology patients from rural backgrounds differ in their health attitudes and hope levels compared with those from urban backgrounds? The aim of this study was to determine the utility of the selected validated instruments, newly diagnosed patients' willingness and ability to complete the composite survey instrument, and to identify likely issues for inclusion and/or greater focus in the larger project. As pilot studies are also used to develop or refine research questions and hypotheses, this article also considers some research questions for the planned large scale study. METHODS: Self-administered questionnaire survey of 47 patients newly referred to the Medical Oncology Department in The Townsville Cancer Centre. Scales used were: the EORTC QLQ-C30 to assess symptom burden and quality of life; the Duke UNS Functional Social Support Questionnaire to assess social support; the Herth Hope Index to assess hope; and the Multi-Dimensional Health Locus of Control to assess health beliefs. Data were collated and transformed according to the various scales' scoring manuals. Rurality was ascertained using the RRMA classification and patient self-assessment. Uni-variate analyses were conducted as small numbers precluded multi-variate analysis. Non-parametric Mann-Whitney U and Kruskal-Wallis tests were used where data were skewed, or categorical. Monte-Carlo estimations of p-values were generated. RESULTS: In all, 28 of 47 patients classified as rural, 27 were suitable for curative treatment, and 31 were male. Median age was 56 years. Some respondents (17%) identified as 'rural', although they had an urban residence, and vice versa. Health attitude scores were not affected by global health scores or by intent of treatment (palliative/curative). Males scored significantly higher for belief in chance. Rural patients scored significantly higher for internal belief and belief in chance. No statistically significant differences were evident between rural/urban patients by gender, nor social support scores. Hope levels were generally high with no significant difference between urban and rural patients, regardless of treatment intent. DISCUSSION: The study does reveal differences in health attitudes between urban and rural populations; however, there are several confounding factors which may contribute to this, especially gender. In this study women were under-represented. People with fatalistic beliefs (high belief in chance) tend to have poor initiative in health matters which may cause delay in seeking treatment, or poor compliance with treatment. Analysis is limited by small numbers of patients. This study is a pilot to a larger project to investigate health attitudes and decisions by oncology patients in northern Queensland. The questionnaire was well received by patients, but the need for a dedicated recruitment person was evident. There is a need to determine how patients identify in terms of rurality over and above their actual place of residence.
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Actitud Frente a la Salud , Neoplasias/psicología , Población Rural , Población Urbana , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Queensland , Apoyo Social , Encuestas y CuestionariosRESUMEN
The concentrations of gas-phase PCBs were measured from March 2002 to June 2003 at two sites of the Venice Lagoon and at one site of the Euganei hills. The aims of this study were to evaluate the various gas-phase PCB sources, the spatial and temporal variability of PCB concentrations in the gas-phase that enter the Venice Lagoon atmosphere and the influence of the air temperature on PCB trends. The highest annual average concentration of summation PCBs was observed at the station directly influenced by "urban" sources with values about 3 and 1.5 times higher compared to the concentrations found at the stations where "marine" sources and "not subjected to direct local sources" were respectively sampled from. The temporal trends of summation PCBs concentrations were similar at the three sampling stations corresponding to seasonal temperature changes. Greater concentrations occurred in the summer and first autumn months while the lower ones occurred in late autumn and winter. The temperature dependences were investigated using plots of the natural logarithm of the summation PCBs concentrations vs. reciprocal mean temperatures.
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Contaminantes Atmosféricos/análisis , Aire/análisis , Monitoreo del Ambiente , Gases/análisis , Bifenilos Policlorados/análisis , Aire/normas , Italia , Estaciones del AñoRESUMEN
Given the increasing interest in using peat bogs as archives of atmospheric metal deposition, the lack of validated sample preparation methods and suitable certified reference materials has hindered not only the quality assurance of the generated analytical data but also the interpretation and comparison of peat core metal profiles from different laboratories in the international community. Reference materials play an important role in the evaluation of the accuracy of analytical results and are essential parts of good laboratory practice. An ombrotrophic peat bog reference material has been developed by 14 laboratories from nine countries in an inter-laboratory comparison between February and October 2002. The material has been characterised for both acid-extractable and total concentrations of a range of elements, including Al, As, Ca, Cd, Cr, Cu, Fe, Hg, Mg, Mn, Na, Ni, P, Pb, Ti, V and Zn. The steps involved in the production of the reference material (i.e. collection and preparation, homogeneity and stability studies, and certification) are described in detail.
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Monitoreo del Ambiente/métodos , Sedimentos Geológicos/análisis , Contaminantes del Suelo/análisis , Metales Pesados/análisis , Valores de Referencia , Suelo/análisis , Oligoelementos/análisisRESUMEN
Two distinct types of glycine transporter, GlyT-1 and GlyT-2, have been characterised. GlyT-1 and GlyT-2 are known to be differentially expressed amongst CNS areas, but direct functional evidence for their relative contributions to high-affinity glycine uptake by brain tissues is lacking. In the present study, we have used the selective GlyT-1 inhibitor N[3-(4"-fluorophenyl)-3-(4"-phenylphenoxy)propyl]sarcosine (NFPS) to investigate the role of GlyT-1 in mediating glycine uptake. HEK293 cells expressing human GlyT-1c or GlyT-2 showed high levels of Na(+)-dependent glycine uptake, with K(m) values of 117+/-13 and 200+/-22 microM, respectively. NFPS potently inhibited uptake in GlyT-1c cells (IC(50) value 0.22+/-0.03 microM), being around 500-fold more potent than glycine or sarcosine, but had no effect on uptake in GlyT-2 cells (IC(50) >10 microM). Efflux of pre-loaded [3H]-glycine from GlyT-1c cells was increased by glycine or sarcosine, whereas NFPS had no effect on its own but blocked the effects of glycine or sarcosine. These results confirm that NFPS is a potent, selective and non-transportable GlyT-1 inhibitor. Rat cortex and cerebellum synaptosomes also showed a high-affinity Na(+)-dependent component of glycine uptake, with affinities similar to those observed for uptake in GlyT-1c or GlyT-2 cells. In cortex synaptosomes, NFPS and sarcosine produced the same maximal inhibition of uptake as glycine itself. However, in cerebellum synaptosomes, the maximal inhibition produced by NFPS and sarcosine was only half that produced by glycine. In both tissues NFPS was around 1000-fold more potent than glycine or sarcosine. Overall, our findings indicate that high-affinity glycine uptake in cerebral cortex occurs predominantly via GlyT-1. However, in cerebellum, only a part of the high-affinity uptake is mediated by GlyT-1, with the remaining NFPS-insensitive component most likely mediated by GlyT-2.
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Sistemas de Transporte de Aminoácidos Neutros , Proteínas Portadoras/fisiología , Cerebelo/metabolismo , Corteza Cerebral/metabolismo , Glicina/metabolismo , Receptores de Glicina/metabolismo , Sarcosina/farmacología , Sinaptosomas/metabolismo , Animales , Cerebelo/efectos de los fármacos , Corteza Cerebral/efectos de los fármacos , Proteínas de Transporte de Glicina en la Membrana Plasmática , Humanos , Técnicas In Vitro , Ratas , Receptores de Glicina/efectos de los fármacos , Sarcosina/análogos & derivados , Sinaptosomas/efectos de los fármacosRESUMEN
A full pharmacological characterisation of the recently cloned human vanilloid VR1 receptor was undertaken. In whole-cell patch clamp studies, capsaicin (10 microM) elicited a slowly activating/deactivating inward current in human embryonic kidney (HEK293) cells stably expressing human vanilloid VR1 receptor, which exhibited pronounced outward rectification (reversal potential -2.1+/-0.2 mV) and was abolished by capsazepine (10 microM). In FLIPR-based Ca(2+) imaging studies the rank order of potency was resiniferatoxin>olvanil>capsaicin>anandamide, and all were full agonists. Isovelleral and scutigeral were inactive (1 nM-30 microM). The potencies of capsaicin, olvanil and resiniferatoxin, but not anandamide, were enhanced 2- to 7-fold at pH 6.4. Capsazepine, isovelleral and ruthenium red inhibited the capsaicin (100 nM)-induced Ca(2+) response (pK(B)=6.58+/-0.02, 5.33+/-0.03 and 7.64+/-0.03, respectively). In conclusion, the recombinant human vanilloid VR1 receptor stably expressed in HEK293 cells acted as a ligand-gated, Ca(2+)-permeable channel with similar agonist and antagonist pharmacology to rat vanilloid VR1 receptor, although there were some subtle differences.