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1.
Sci Rep ; 9(1): 15827, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31676832

RESUMEN

Spin-polarized supercurrents can be generated with magnetic inhomogeneity at a ferromagnet/spin-singlet-superconductor interface. In such systems, complex magnetic inhomogeneity makes it difficult to functionalise the spin-polarized supercurrents. However, spin-polarized supercurrents in ferromagnet/spin-triplet-superconductor junctions can be controlled by the angle between magnetization and spin of Copper pairs (d-vector), that can effectively be utilized in developing of a field of research known as superconducting spintronics. Recently, we found induction of spin-triplet correlation into a ferromagnet SrRuO3 epitaxially deposited on a spin-triplet superconductor Sr2RuO4, without any electronic spin-flip scattering. Here, we present systematic magnetic field dependence of the proximity effect in Au/SrRuO3/Sr2RuO4 junctions. It is found that induced triplet correlations exhibit strongly anisotropic field response. Such behaviour is attributed to the rotation of the d-vector of Sr2RuO4. This anisotropic behaviour is in contrast with the vortex dynamic. Our results will stimulate study of interaction between ferromagnetism and unconventional superconductivity.

3.
Phys Rev Lett ; 121(7): 077003, 2018 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-30169105

RESUMEN

At a superconductor-ferromagnet (S/F) interface, the F layer can introduce a magnetic exchange field within the S layer, which acts to locally spin split the superconducting density of states. The effect of magnetic exchange fields on superconductivity has been thoroughly explored at S-ferromagnet insulator (S/FI) interfaces for isotropic s-wave S and a thickness that is smaller than the superconducting coherence length. Here we report a magnetic exchange field effect at an all-oxide S/FI interface involving the anisotropic d-wave high temperature superconductor praseodymium cerium copper oxide (PCCO) and the FI praseodymium calcium manganese oxide (PCMO). The magnetic exchange field in PCCO, detected via magnetotransport measurements through the superconducting transition, is localized to the PCCO/PCMO interface with an average magnitude that depends on the presence or absence of magnetic domain walls in PCMO. The results are promising for the development of all-oxide superconducting spintronic devices involving unconventional pairing and high temperature superconductors.

4.
BMC Infect Dis ; 18(1): 107, 2018 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-29506483

RESUMEN

BACKGROUND: Various studies have identified numerous factors associated with poor clinical outcomes in patients with Staphylococcus aureus bacteraemia (SAB). A new study was created to provide deeper insight into in-hospital complications and risk factors for treatment failure. METHODS: Adult patients hospitalised with Staphylococcus aureus bacteraemia (SAB) were recruited prospectively into a multi-centre cohort. The primary outcome was treatment failure at 30 days (composite of all-cause mortality, persistent bacteraemia, or recurrent bacteraemia), and secondary measures included in-hospital complications and mortality at 6- and 12-months. Data were available for 222 patients recruited from February 2011 to December 2012. RESULTS: Treatment failure at 30-days was recorded in 14.4% of patients (30-day mortality 9.5%). Multivariable analysis predictors of treatment failure included age > 70 years, Pitt bacteraemia score ≥ 2, CRP at onset of SAB > 250 mg/L, and persistent fevers after SAB onset; serum albumin at onset of SAB, receipt of appropriate empiric treatment, recent healthcare attendance, and performing echocardiography were protective. 6-month and 12-month mortality were 19.1% and 24.2% respectively. 45% experienced at least one in-hospital complication, including nephrotoxicity in 19.5%. CONCLUSIONS: This study demonstrates significant improvements in 30-day outcomes in SAB in Australia. However, we have identified important areas to improve outcomes from SAB, particularly reducing renal dysfunction and in-hospital treatment-related complications.


Asunto(s)
Infecciones Estafilocócicas/epidemiología , Staphylococcus aureus/aislamiento & purificación , Adulto , Factores de Edad , Anciano , Anciano de 80 o más Años , Antibacterianos/farmacología , Australia/epidemiología , Proteína C-Reactiva/análisis , Estudios de Cohortes , Ecocardiografía , Femenino , Mortalidad Hospitalaria , Hospitalización , Humanos , Modelos Logísticos , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Morbilidad , Factores de Riesgo , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/mortalidad , Staphylococcus aureus/efectos de los fármacos , Insuficiencia del Tratamiento , Vancomicina/farmacología
5.
Nature ; 543(7643): 103-107, 2017 03 02.
Artículo en Inglés | MEDLINE | ID: mdl-28225752

RESUMEN

The prefrontal cortex is a critical neuroanatomical hub for controlling motivated behaviours across mammalian species. In addition to intra-cortical connectivity, prefrontal projection neurons innervate subcortical structures that contribute to reward-seeking behaviours, such as the ventral striatum and midline thalamus. While connectivity among these structures contributes to appetitive behaviours, how projection-specific prefrontal neurons encode reward-relevant information to guide reward seeking is unknown. Here we use in vivo two-photon calcium imaging to monitor the activity of dorsomedial prefrontal neurons in mice during an appetitive Pavlovian conditioning task. At the population level, these neurons display diverse activity patterns during the presentation of reward-predictive cues. However, recordings from prefrontal neurons with resolved projection targets reveal that individual corticostriatal neurons show response tuning to reward-predictive cues, such that excitatory cue responses are amplified across learning. By contrast, corticothalamic neurons gradually develop new, primarily inhibitory responses to reward-predictive cues across learning. Furthermore, bidirectional optogenetic manipulation of these neurons reveals that stimulation of corticostriatal neurons promotes conditioned reward-seeking behaviour after learning, while activity in corticothalamic neurons suppresses both the acquisition and expression of conditioned reward seeking. These data show how prefrontal circuitry can dynamically control reward-seeking behaviour through the opposing activities of projection-specific cell populations.


Asunto(s)
Conducta Apetitiva/fisiología , Señales (Psicología) , Vías Nerviosas , Neuronas/fisiología , Corteza Prefrontal/citología , Corteza Prefrontal/fisiología , Recompensa , Animales , Calcio/análisis , Condicionamiento Clásico/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Microscopía de Fluorescencia por Excitación Multifotónica , Imagen Molecular , Plasticidad Neuronal , Núcleo Accumbens/citología , Núcleo Accumbens/fisiología , Tálamo/citología , Tálamo/fisiología
6.
J Neuroendocrinol ; 28(5)2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-26999292

RESUMEN

Exposure to stress during early development can permanently influence an individual's physiology and behaviour, and affect its subsequent health. The extent to which elevated glucocorticoids cause such long-term 'programming' remains largely untested. In the present study, using the Japanese quail as our study species, we independently manipulated exposure to corticosterone during pre- and/or post-natal development and investigated the subsequent effects on global gene expression profiles within the hippocampus and hypothalamus upon achieving adulthood. Our results showed that the changes in transcriptome profiles in response to corticosterone exposure clearly differed between the hippocampus and the hypothalamus. We also showed that these effects depended on the developmental timing of exposure and identified brain-region specific gene expression patterns that were either: (i) similarly altered by corticosterone regardless of the developmental stage in which hormonal exposure occurred or (ii) specifically and uniquely altered by either pre-natal or post-natal exposure to corticosterone. Corticosterone-treated birds showed alterations in networks of genes that included known markers of the programming actions of early-life adversity (e.g. brain-derived neurotrophic factor and mineralocorticoid receptor within the hippocampus; corticotrophin-releasing hormone and serotonin receptors in the hypothalamus). Altogether, for the first time, these findings provide experimental support for the hypothesis that exposure to elevated glucocorticoids during development may be a key hormonal signalling pathway through which the long-term phenotypic effects associated with early-life adversity emerge and potentially persist throughout the lifespan. These data also highlight that stressors might have different long-lasting impacts on the brain transcriptome depending on the developmental stage in which they are experienced; more work is now required to relate these mechanisms to organismal phenotypic differences.


Asunto(s)
Corticosterona/administración & dosificación , Glucocorticoides/administración & dosificación , Hipocampo/metabolismo , Hipotálamo/metabolismo , Efectos Tardíos de la Exposición Prenatal/genética , Estrés Fisiológico , Transcriptoma , Animales , Proteínas Aviares/genética , Coturnix , Femenino , Hipocampo/efectos de los fármacos , Hipocampo/crecimiento & desarrollo , Hipotálamo/efectos de los fármacos , Hipotálamo/crecimiento & desarrollo , Masculino , Embarazo , Efectos Tardíos de la Exposición Prenatal/metabolismo
7.
J Biomol Screen ; 19(4): 526-37, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24361645

RESUMEN

The existence of phenotypic differences in the drug responses of 3D tissue relative to 2D cell culture is a concern in high-content drug screening. Biodynamic imaging is an emerging technology that probes 3D tissue using short-coherence dynamic light scattering to measure the intracellular motions inside tissues in their natural microenvironments. The information content of biodynamic imaging is displayed through tissue dynamics spectroscopy (TDS) but has not previously been correlated against morphological image analysis of 2D cell culture. In this article, a set of mitochondria-affecting compounds (FCCP, valinomycin, nicardipine, ionomycin) and Raf kinase inhibitors (PLX4032, PLX4720, GDC, and sorafenib) are applied to multicellular tumor spheroids from two colon adenocarcinoma cell lines (HT-29 and DLD-1). These were screened by TDS and then compared against conventional image-based high-content analysis (HCA). The responses to the Raf inhibitors PLX4032 and PLX4720 are grouped separately by cell line, reflecting the Braf/Kras difference in these cell lines. There is a correlation between TDS and HCA phenotypic clustering for most cases, which demonstrates the ability of dynamic measurements to capture phenotypic responses to drugs. However, there are significant 2D versus 3D phenotypic differences exhibited by several of the drugs/cell lines.


Asunto(s)
Evaluación Preclínica de Medicamentos , Mitocondrias/efectos de los fármacos , Inhibidores de Proteínas Quinasas/farmacología , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Espectrofotometría/métodos , Esferoides Celulares/efectos de los fármacos , Línea Celular Tumoral , Análisis por Conglomerados , Descubrimiento de Drogas , Evaluación Preclínica de Medicamentos/métodos , Ensayos de Selección de Medicamentos Antitumorales , Ensayos Analíticos de Alto Rendimiento , Humanos , Inhibidores de Proteínas Quinasas/toxicidad , Proteínas Proto-Oncogénicas B-raf/metabolismo , Células Tumorales Cultivadas
8.
Food Chem ; 149: 62-70, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24295677

RESUMEN

In French Guiana, "diversity" within the Palm family is obvious since more than 75 species have been identified. Oenocarpus bataua Mart., called "patawa" is well known for its culinary uses whereas literature on its phytochemical composition and biological properties remains poor. This work deals with determining the antioxidant activity of this palm fruit and its polyphenol composition; Euterpe oleracea (açai) used as a reference. It turned out that patawa had a stronger antioxidant activity than açai in TEAC and FRAP tests. A similar activity was observed by DPPH assay whereas in ORAC and KRL tests, that açai showed an antioxidant activity respectively 2.6 and 1.5 fold higher than patawa. Polyphenolic composition, determined by UPLC/MS(n), would imply the presence of anthocyanins, condensed tannins, stilbenes and phenolic acids, well known for their biological activities. These results present patawa fruit as a new amazonian resource for cosmetics, food and pharmaceuticals purposes.


Asunto(s)
Antioxidantes/química , Arecaceae/química , Extractos Vegetales/química , Frutas/química , Polifenoles/química
9.
BJOG ; 120(10): 1248-59; discussion 1256-7, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23834406

RESUMEN

OBJECTIVE: To determine the use of pharmacologic analgesia during childbirth when antenatal hypnosis is added to standard care. DESIGN: Randomised controlled clinical trial, conducted from December 2005 to December 2010. SETTING: The largest tertiary referral centre for maternity care in South Australia. POPULATION: A cohort of 448 women at >34 weeks of gestation, with a singleton pregnancy and cephalic presentation, planning a vaginal birth. Exclusions were: the need for an interpreter; pre-existing pain; psychiatric illness; younger than 18 years; and previous experience of hypnosis for childbirth. METHODS: All participants received usual care. The group of women termed Hypnosis + CD (hypnotherapist guided) were offered three antenatal live hypnosis sessions plus each session's corresponding audio CD for further practise, as well as a final fourth CD to listen to during labour. The group of women termed CD only (nurse administered) were played the same antenatal hypnosis CDs as group 1, but did not receive live hypnosis training. The control group participants were given no additional intervention or CDs. MAIN OUTCOME MEASURE: Use of pharmacological analgesia during labour and childbirth. RESULTS: No difference in the use of pharmacological analgesia during labour and childbirth was found comparing hypnosis + CD with control (81.2 versus 76.2%; relative risk, RR 1.07; 95% confidence interval, 95% CI 0.95-1.20), or comparing CD only with control (76.9 versus 76.2%, RR 1.01, 95% CI 0.89-1.15). CONCLUSIONS: Antenatal group hypnosis using the Hypnosis Antenatal Training for Childbirth (HATCh) intervention in late pregnancy does not reduce the use of pharmacological analgesia during labour and childbirth.


Asunto(s)
Analgesia Obstétrica , Analgésicos/uso terapéutico , Anestesia Obstétrica , Hipnosis Anestésica , Dolor de Parto/terapia , Adulto , Discos Compactos , Intervalos de Confianza , Femenino , Humanos , Parto , Embarazo , Atención Prenatal , Método Simple Ciego
10.
Antimicrob Agents Chemother ; 57(4): 1654-63, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23335735

RESUMEN

A ratio of the vancomycin area under the concentration-time curve to the MIC (AUC/MIC) of ≥ 400 has been associated with clinical success when treating Staphylococcus aureus pneumonia, and this target was recommended by recently published vancomycin therapeutic monitoring consensus guidelines for treating all serious S. aureus infections. Here, vancomycin serum trough levels and vancomycin AUC/MIC were evaluated in a "real-world" context by following a cohort of 182 patients with S. aureus bacteremia (SAB) and analyzing these parameters within the critical first 96 h of vancomycin therapy. The median vancomycin trough level at this time point was 19.5 mg/liter. There was a significant difference in vancomycin AUC/MIC when using broth microdilution (BMD) compared with Etest MIC (medians of 436.1 and 271.5, respectively; P < 0.001). Obtaining the recommended vancomycin target AUC/MIC of ≥ 400 using BMD was not associated with lower 30-day all-cause or attributable mortality from SAB (P = 0.132 and P = 0.273, respectively). However, an alternative vancomycin AUC/MIC of >373, derived using classification and regression tree analysis, was associated with reduced mortality (P = 0.043) and remained significant in a multivariable model. This study demonstrated that we obtained vancomycin trough levels in the target therapeutic range early during the course of therapy and that obtaining a higher vancomycin AUC/MIC (in this case, >373) within 96 h was associated with reduced mortality. The MIC test method has a significant impact on vancomycin AUC/MIC estimation. Clinicians should be aware that the current target AUC/MIC of ≥ 400 was derived using the reference BMD method, so adjustments to this target need to be made when calculating AUC/MIC ratio using other MIC testing methods.


Asunto(s)
Antibacterianos/uso terapéutico , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/mortalidad , Vancomicina/uso terapéutico , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Estudios Retrospectivos , Staphylococcus aureus/efectos de los fármacos , Staphylococcus aureus/patogenicidad , Vancomicina/farmacocinética , Vancomicina/farmacología
11.
J Lab Autom ; 18(1): 85-98, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22968419

RESUMEN

We have developed an automated system for drug screening using a single-cell-multiple functional response technology. The approach uses a semiautomated preparatory system, high-speed sample collection, and a unique analytical tool that provides instantaneous results for compound dilutions using 384-well plates. The combination of automation and rapid robotic sampling increases quality control and robustness. High-speed flow cytometry is used to collect single-cell results together with a newly defined analytical tool for extraction of IC(50) curves for multiple assays per cell. The principal advantage is the extreme speed of sample collection, with results from a 384-well plate being completed for both collection and data processing in less than 10 min. Using this approach, it is possible to extract detailed drug response information in a highly controlled fashion. The data are based on single-cell results, not populations. With simultaneous assays for different functions, it is possible to gain a more detailed understanding of each drug/compound interaction. Combined with integrated advanced data processing directly from raw data files, the process from sampling to analytical results is highly intuitive. Direct PubMed links allow review of drug structure and comparisons with similar compounds.


Asunto(s)
Evaluación Preclínica de Medicamentos/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Análisis de la Célula Individual/métodos , Automatización , Citometría de Flujo , Células HL-60 , Humanos , Concentración 50 Inhibidora , Mitocondrias/metabolismo , Factores de Tiempo
12.
Sci Total Environ ; 437: 315-22, 2012 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-22954652

RESUMEN

The accumulation of phosphorus (P) in the bottom sediment of field drainage ditches poses a threat to the ecology both of the ditch water and downstream water courses. We investigated the amounts, forms and internal loading of sediment-bound P along two drainage ditches that regulate water levels in a basin fen (~200 ha) supporting a mixture of restored wetland and drained agricultural fields. Water levels in the Lady's Drove Rhyne are currently managed to enhance the biodiversity of the wetland (Catcott Lows Reserve - an area formerly cultivated for arable crop production); whereas, the East Ditch is managed to drain adjoining land that remains under arable and livestock production. Laboratory-based chemical fractionation schemes were used to characterise the forms and potential mobility of the sediment-bound P, whilst pore-water equilibrators were employed in situ to evaluate the diffusive flux of P through the sediment-water column, and to characterise the corresponding redox conditions. Along both ditches, sediment pore-water profiles indicated conditions ranging from weakly to very reducing conditions with increasing depth, and net fluxes of P from the sediment to overlying water. P flux values ranged from 0.33 to 1.30 mg m(-2) day(-1). Both the degree of P saturation (DPS) of the sediment and NaOH extractable (Fe/Al-bound) P correlated significantly (P<0.05) with P flux. Both in the wetland and agricultural ditches, by far the highest values for P flux were recorded at sites closest to points of drainage water entry from the corresponding, adjoining land. Although the P flux data were obtained from only a single sampling event, this study highlights the contribution of historical as well as ongoing agricultural land use on the sustained elevated P status of ditch sediments in lowland catchments.


Asunto(s)
Sedimentos Geológicos/química , Fósforo/química , Humedales , Agricultura , Inglaterra , Monitoreo del Ambiente , Sedimentos Geológicos/análisis , Fósforo/análisis , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/química
13.
Expert Opin Drug Discov ; 7(8): 679-93, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22708834

RESUMEN

INTRODUCTION: Flow cytometry has been around for over 40 years, but only recently has the opportunity arisen to move into the high-throughput domain. The technology is now available and is highly competitive with imaging tools under the right conditions. Flow cytometry has, however, been a technology that has focused on its unique ability to study single cells and appropriate analytical tools are readily available to handle this traditional role of the technology. AREAS COVERED: Expansion of flow cytometry to a high-throughput (HT) and high-content technology requires both advances in hardware and analytical tools. The historical perspective of flow cytometry operation as well as how the field has changed and what the key changes have been discussed. The authors provide a background and compelling arguments for moving toward HT flow, where there are many innovative opportunities. With alternative approaches now available for flow cytometry, there will be a considerable number of new applications. These opportunities show strong capability for drug screening and functional studies with cells in suspension. EXPERT OPINION: There is no doubt that HT flow is a rich technology awaiting acceptance by the pharmaceutical community. It can provide a powerful phenotypic analytical toolset that has the capacity to change many current approaches to HT screening. The previous restrictions on the technology, based on its reduced capacity for sample throughput, are no longer a major issue. Overcoming this barrier has transformed a mature technology into one that can focus on systems biology questions not previously considered possible.


Asunto(s)
Citometría de Flujo/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Interpretación Estadística de Datos , Evaluación Preclínica de Medicamentos/métodos , Humanos , Preparaciones Farmacéuticas
14.
Nat Commun ; 3: 838, 2012 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-22588300

RESUMEN

The dynamics of an order parameter's amplitude and phase determines the collective behaviour of novel states emerging in complex materials. Time- and momentum-resolved pump-probe spectroscopy, by virtue of measuring material properties at atomic and electronic time scales out of equilibrium, can decouple entangled degrees of freedom by visualizing their corresponding dynamics in the time domain. Here we combine time-resolved femotosecond optical and resonant X-ray diffraction measurements on charge ordered La(1.75)Sr(0.25)NiO(4) to reveal unforeseen photoinduced phase fluctuations of the charge order parameter. Such fluctuations preserve long-range order without creating topological defects, distinct from thermal phase fluctuations near the critical temperature in equilibrium. Importantly, relaxation of the phase fluctuations is found to be an order of magnitude slower than that of the order parameter's amplitude fluctuations, and thus limits charge order recovery. This new aspect of phase fluctuations provides a more holistic view of the phase's importance in ordering phenomena of quantum matter.

15.
J Assist Reprod Genet ; 28(12): 1223-8, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22071884

RESUMEN

PURPOSE: There is increasing concern that environmental chemicals have a direct effect on fertility. Heavy metals such as mercury have been shown to affect various organ systems in humans including nervous system and skin, however they could also act as endocrine disrupting chemicals adversely affecting fertility. Metals such as zinc and selenium are essential micronutrients with diverse functions that may be important for reproductive outcomes. We measured mercury, zinc and selenium levels in the hair, a reliable reflection of long term environmental exposure and dietary status, to correlate with the outcome of ovarian hyperstimulation for in vitro fertilisation (IVF) treatment. METHODS: We analysed the hair of 30 subfertile women for mercury, zinc and selenium using inductively coupled mass spectrometry. Each woman underwent one cycle of IVF treatment. Correlation between the levels of these trace metals and treatment outcomes was investigated. RESULTS: Thirty women were recruited with mean (±SD) age of 32.7(4.4) years and BMI of 25.4(5.0)kg/m(2). Hair mercury concentration showed a negative correlation with oocyte yield (p < 0.05,ßcoefficient 0.38) and follicle number (p = 0.03,ß coefficient0.19) after ovarian stimulation. Zinc and selenium levels in hair correlated positively with oocyte yield after ovarian stimulation (p < 0.05,ß coefficient0.15) and (p = 0.03,ß coefficient0.21) respectively. Selenium levels in hair correlated significantly with follicle number following stimulation (p = 0.04, ßcoefficient0.22). There was no correlation between mercury, zinc and selenium in hair and their corresponding serum levels. CONCLUSION: These data suggest that mercury had a deleterious effect whilst there was a positive effect for zinc and selenium in the ovarian response to gonadotrophin therapy for IVF. Hair analysis offers a novel method of investigating the impact of long-term exposure to endocrine disruptors and nutritional status on reproductive outcomes.


Asunto(s)
Disruptores Endocrinos/análisis , Exposición a Riesgos Ambientales , Fertilización In Vitro , Metales Pesados/análisis , Estado Nutricional , Inducción de la Ovulación , Adulto , Disruptores Endocrinos/sangre , Femenino , Cabello/química , Humanos , Infertilidad Femenina/metabolismo , Infertilidad Femenina/terapia , Mercurio/análisis , Mercurio/sangre , Metales Pesados/sangre , Oocitos/efectos de los fármacos , Oocitos/metabolismo , Proyectos Piloto , Estudios Prospectivos , Selenio/análisis , Selenio/sangre , Zinc/análisis , Zinc/sangre
16.
Rural Remote Health ; 10(3): 1402, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20722462

RESUMEN

INTRODUCTION: General practitioner proceduralists are a distinct and highly trained cohort of doctors who provide procedural services in hospitals and emergency rooms throughout Australia. However, their value is not well recognised in the wider system of primary health care. Consequently, an understanding of the landscape of GP procedural practice is an essential element of health service planning now and in the future. Therefore, empirical data from a 2008 study of GP procedural medicine in the Bogong region of north-east Victoria and southern New South Wales is presented. The implications of shifting trends in the demand for and supply of the GP procedural workforce on future health services is examined. A comprehensive literature review established past and future trends in procedural medicine and provided a context for three research questions: (1) What procedures are being performed by GP proceduralists in the Bogong region? (2) What procedures are no longer performed and why? (3) What is the likely future of GP procedural practice in the next 5 to 10 years? METHOD: A qualitative case study methodology was chosen to explore the factors that influence the nature of GP procedural medicine. A population of 70 GPs were initially identified as practising obstetric, surgical or anaesthetic procedures. Of these, 38 participated in structured interviews, 21 were electronically surveyed and 11 were excluded from the study. Combined interview and survey responses gave a response rate of 81%. Five health service executives and a senior Department of Human Services manager were interviewed to gather their perspectives about the research questions. Content and thematic analysis revealed key issues of importance. Data-sets were examined to analyse themes associated with trends in GP procedural medicine over time. RESULTS: General practitioner proceduralists are attracted by diversity, challenge and passion for procedural work. However, there has been a gradual but sustained decline in the volume and complexity of procedural work due, in part, to shifts in community demography, changing medical practices, the rise of specialisation, the centralisation of services, infrastructure and other costs, and fear of litigation. Moreover, an ageing workforce and a shift in the demographic profile of GPs and the pressures of procedural life have contributed to a decline in GP proceduralist numbers. Nevertheless, there remains a substantial demand for GP procedural medicine in rural communities. CONCLUSIONS: Rural towns are dependent upon GP proceduralists to ensure the continuing health and sustainability of local communities. However, the existence of a viable and robust workforce of GP proceduralists is at a 'breaking point'. Until GP proceduralists are recognised and counted as a distinct cohort of valued and highly trained medical practitioners they will remain the 'hidden heart' of primary care in rural and regional Australia. An holistic approach must be adopted to attract, train, maintain and recognise the GP proceduralists' unique place in rural health. With the Australian health system under government review, there are opportunities to revitalise GP procedural practice as a long term, viable and challenging career choice and ensure on-going support for rural in-patient and emergency department services.


Asunto(s)
Medicina Familiar y Comunitaria , Médicos Generales/provisión & distribución , Médicos de Familia/provisión & distribución , Atención Primaria de Salud , Regionalización/organización & administración , Servicios de Salud Rural , Actitud del Personal de Salud , Australia , Investigación sobre Servicios de Salud , Humanos , Salud Rural , Servicios de Salud Rural/tendencias , Recursos Humanos
17.
Int J Phytoremediation ; 12(3): 243-54, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20734619

RESUMEN

We studied the reuse of selenium (Se)-laden effluent for producing canola (Brassica napus) and subsequent bioproducts in central California. Canola was irrigated with poor quality waters [electrical conductivity (EC) of approximately 5 dS m(-1) sulfate-salinity, 5 mg B L(-1), and 0.25 mg Se L(-1)]. Typical seed yields were 2.2 metric tons ha(-1). Seeds were processed for their oil, and transesterified to produce ASTM-quality biodiesel (BD) blends. The resulting Se-enriched seed cake meal (containing approximately 2 mg Se kg(-1) DM) was used in a dairy feed trial. Seventy-two Jersey and Holstein cows, 36 respectively, were fed Se-enriched canola meal as 6.2% of their daily feed ration for five weeks. Blood and milk samples were collected weekly and analyzed for total Se. This study showed that Se-enriched canola meal did not significantly increase total blood Se content in either cow breed. Milk Se concentrations did, however, significantly increase to safe levels of 59 microg Se L(-1) and 52 microg Se L(-1) in Jersey and Holstein cows, respectively. The production of BD 20 biofuels and Se-enriched feed meal from canola irrigated with poor quality waters may help sustain similar phytomanagement strategies under Se-rich conditions.


Asunto(s)
Alimentación Animal/análisis , Biocombustibles/análisis , Brassica napus/crecimiento & desarrollo , Drenaje de Agua , Selenio/análisis , Eliminación de Residuos Líquidos , Purificación del Agua , Animales , Biodegradación Ambiental , California , Bovinos , Industria Lechera , Leche/química , Selenio/sangre
18.
Neurology ; 73(2): 142-9, 2009 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-19398680

RESUMEN

OBJECTIVE: To reassess the evidence for management issues related to the care of women with epilepsy (WWE) during pregnancy, including preconceptional folic acid use, prenatal vitamin K use, risk of hemorrhagic disease of the newborn, clinical implications of placental and breast milk transfer of antiepileptic drugs (AEDs), risks of breastfeeding, and change in AED levels during pregnancy. METHODS: A 20-member committee evaluated the available evidence based on a structured literature review and classification of relevant articles published between 1985 and October 2007. RESULTS: Preconceptional folic acid supplementation is possibly effective in preventing major congenital malformations in the newborns of WWE taking AEDs. There is inadequate evidence to determine if the newborns of WWE taking AEDs have a substantially increased risk of hemorrhagic complications. Primidone and levetiracetam probably transfer into breast milk in amounts that may be clinically important. Valproate, phenobarbital, phenytoin, and carbamazepine probably are not transferred into breast milk in clinically important amounts. Pregnancy probably causes an increase in the clearance and a decrease in the concentration of lamotrigine, phenytoin, and to a lesser extent carbamazepine, and possibly decreases the level of levetiracetam and the active oxcarbazepine metabolite, the monohydroxy derivative. RECOMMENDATIONS: Supplementing women with epilepsy with at least 0.4 mg of folic acid before they become pregnant may be considered (Level C). Monitoring of lamotrigine, carbamazepine, and phenytoin levels during pregnancy should be considered (Level B) and monitoring of levetiracetam and oxcarbazepine (as monohydroxy derivative) levels may be considered (Level C). A paucity of evidence limited the strength of many recommendations.


Asunto(s)
Anticonvulsivantes/uso terapéutico , Lactancia Materna , Anomalías Congénitas/prevención & control , Epilepsia/tratamiento farmacológico , Ácido Fólico/administración & dosificación , Complicaciones del Embarazo/tratamiento farmacológico , Vitamina K/administración & dosificación , Anticonvulsivantes/efectos adversos , Anticonvulsivantes/farmacocinética , Anomalías Congénitas/epidemiología , Epilepsia/epidemiología , Epilepsia/fisiopatología , Femenino , Humanos , Recién Nacido , Leche Humana/metabolismo , Placenta/metabolismo , Embarazo , Riesgo , Sangrado por Deficiencia de Vitamina K/epidemiología , Sangrado por Deficiencia de Vitamina K/etiología , Sangrado por Deficiencia de Vitamina K/prevención & control
19.
J Environ Manage ; 88(2): 211-8, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-17433529

RESUMEN

The application of microwave heating technology to conventional gas stripping processes has been investigated in the remediation of contaminated drill cuttings. The technical feasibility and limitations of nitrogen and steam stripping processes are demonstrated, and it is shown that the combination of microwave heating with the stripping process offers a step change in performance. Order of magnitude improvements in processing time are shown for the microwave-assisted processes, as well as greatly improved levels of remediation. The mechanisms of contaminant removal are discussed, along with the phenomena which occur with microwave heating processes. The energy requirements of each of pure gas and microwave-assisted processes are also discussed, and the potential applications of each technology are highlighted relative to the overall remediation requirements.


Asunto(s)
Sedimentos Geológicos/química , Microondas , Petróleo , Calor
20.
J Neuroendocrinol ; 19(12): 966-73, 2007 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-18001326

RESUMEN

Galanin is a small neuropeptide that mediates its effects via three receptor isoforms: galanin receptor-1, galanin receptor-2 and galanin receptor-3 (Gal-R1, Gal-R2 and Gal-R3). Galanin is thought to be an important intermediate in signalling in the hypothalamic-pituitary-gonadal axis and has been widely detected in the ovine hypothalamus. The expression of galanin and Gal-R1 has been reported to fluctuate during the reproductive cycle. Although the distribution of Gal-R1 has been determined in the ovine hypothalamus, the distribution of Gal-R2 was hitherto unknown. Using immunohistological and immunofluorescence techniques, we have mapped the distribution of Gal-R2 in the ovine hypothalamus, collected during the follicular phase of the oestrous cycle and examined colocalisation of Gal-R2 with oestrogen receptor alpha (ERalpha) and gonadotrophin-releasing hormone (GnRH). Gal-R2 was expressed in several regions of the hypothalamus (supraoptic nucleus, paraventricular nucleus, ventromedial nucleus, arcuate nucleus) but not as widely expressed as Gal-R1. Areas of Gal-R2 expression overlapped with those reported for Gal-R1. We observed that, in certain defined regions of the hypothalamus, up to 50% of neurones that express Gal-R2 also express ERalpha. No neurones coexpressed Gal-R2 and GnRH. Thus, we conclude that, in follicular phase animals, this receptor plays little or no role in direct intermediary signal transmission in GnRH-mediated control of the reproductive cycle.


Asunto(s)
Hormona Liberadora de Gonadotropina/metabolismo , Hipotálamo/metabolismo , Neuronas/metabolismo , Receptor de Galanina Tipo 2/metabolismo , Animales , Receptor alfa de Estrógeno/metabolismo , Receptor alfa de Estrógeno/fisiología , Ciclo Estral/fisiología , Femenino , Técnica del Anticuerpo Fluorescente Indirecta , Hormona Liberadora de Gonadotropina/biosíntesis , Hipotálamo/citología , Inmunohistoquímica , Receptor de Galanina Tipo 2/biosíntesis , Ovinos
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