Quantifying citrate-enhanced phosphate root uptake using microdialysis.

AIMS: Organic acid exudation by plant roots is thought to promote phosphate (P) solubilisation and bioavailability in soils with poorly available nutrients. Here we describe a new combined experimental (microdialysis) and modelling approach to quantify citrate-enhanced P desorption and its importance for root P uptake. METHODS: To mimic the rhizosphere, microdialysis probes were placed in soil and perfused with citrate solutions (0.1, 1.0 and 10 mM) and the amount of P recovered from soil used to quantify rhizosphere P availability. Parameters in a mathematical model describing probe P uptake, citrate exudation, P movement and citrate-enhanced desorption were fit to the experimental data. These parameters were used in a model of a root which exuded citrate and absorbed P. The importance of soil citrate-P mobilisation for root P uptake was then quantified using this model. RESULTS: A plant needs to exude citrate at a rate of 0.73 µmol cm-1 of root h-1 to see a significant increase in P absorption. Microdialysis probes with citrate in the perfusate were shown to absorb similar quantities of P to an exuding root. CONCLUSION: A single root exuding citrate at a typical rate (4.3 × 10-5 µmol m-1 of root h-1) did not contribute significantly to P uptake. Microdialysis probes show promise for measuring rhizosphere processes when calibration experiments and mathematical modelling are used to decouple microdialysis and rhizosphere mechanisms.

Effects of feed restriction during pregnancy on maternal reproductive outcome, foetal hepatic IGF gene expression and offspring performance in the rabbit.

Primiparous female rabbits have high nutritional requirements and, while it is recommended that they are subjected to an extensive reproductive rhythm, this could lead to overweight, affecting reproductive outcomes. We hypothesised that restricting food intake during the less energetic period of gestation could improve reproductive outcome without impairing offspring viability. This study compares two groups of primiparous rabbit does in an extensive reproductive programme, one in which feed was restricted from Day 0 to Day 21 of gestation (R021), and another in which does were fed ad libitum (control) throughout pregnancy. The mother and offspring variables compared were (1) mother reproductive outcomes at the time points pre-implantation (Day 3 postartificial insemination [AI]), preterm (Day 28 post-AI) and birth; and (2) the prenatal offspring characteristic IGF system gene expression in foetal liver, liver fibrosis and foetus sex ratio, and postnatal factor viability and growth at birth, and survival and growth until weaning. Feed restriction did not affect the conception rate, embryo survival, or the number of morulae and blastocysts recovered at Day 3 post-AI. Preterm placenta size and efficiency were similar in the two groups. However, both implantation rate (P < 0.001) and the number of foetuses (P = 0.05) were higher in the R021 mothers than controls, while there was no difference in foetal viability. Foetal size and weight, the weights of most organs, organ weight/BW ratios and sex ratio were unaffected by feed restriction; these variables were only affected by uterine position (P < 0.05). Conversely, in the R021 does, foetal liver IGBP1 and IGF2 gene expression were dysregulated despite no liver fibrosis and a normal liver structure. No effects of restricted feed intake were produced on maternal fertility, prolificacy, or offspring birth weight, but control females weaned more kits. Litter weight and mortality rate during the lactation period were also unaffected. In conclusion, pre-implantation events and foetal development were unaffected by feed restriction. While some genes of the foetal hepatic IGF system were dysregulated during pregnancy, liver morphology appeared normal, and the growth of foetuses and kits until weaning was unmodified. This strategy of feed restriction in extensive reproductive rhythms seems to have no significant adverse effects on dam reproductive outcome or offspring growth and viability until weaning.

Role of nerve growth factor in the reproductive physiology of female rabbits: A review.

Rabbit does are reflex ovulators such that coitus is needed to release GnRH and elicit the LH surge that triggers the ovulation of mature oocytes. However, the mechanisms eliciting ovulation in this species remain unclear. One of the most promising recently discovered candidates with a role in female reproductive physiology is nerve growth factor beta (ß-NGF). This neurotrophin and its high-affinity receptor TrkA and low affinity receptor p75, is present in all compartments of the ovary, oviduct and uterus suggesting a physiologic role in ovarian folliculogenesis, steroidogenesis, ovulation, luteogenesis and embryo development. Besides, evidence exists that ß-NGF found in seminal plasma could exert a modulatory role in the female hypothalamus-pituitary-ovarian axis contributing to the adrenergic and cholinergic neuronal stimulus of GnRH neurons in an endocrine manner during natural mating. Probably, the paracrine and local roles of the neurotrophin in steroidogenesis and ovulation reinforce the neuroendocrine pathway that leads to ovulation. This review updates knowledge of the role of ß-NGF in rabbit reproduction, including its possible contribution to the mechanisms of action that induce ovulation, and discusses perspectives for the future applications of this neurotrophin on rabbit farms.

Cell fishing: A similarity based approach and machine learning strategy for multiple cell lines-compound sensitivity prediction.

The prediction of cell-lines sensitivity to a given set of compounds is a very important factor in the optimization of in-vitro assays. To date, the most common prediction strategies are based upon machine learning or other quantitative structure-activity relationships (QSAR) based approaches. In the present research, we propose and discuss a straightforward strategy not based on any learning modelling but exclusively relying upon the chemical similarity of a query compound to reference compounds with annotated activity against cell lines. We also compare the performance of the proposed method to machine learning predictions on the same problem. A curated database of compounds-cell lines associations derived from ChemBL version 22 was created for algorithm construction and cross-validation. Validation was done using 10-fold cross-validation and testing the models on new data obtained from ChemBL version 25. In terms of accuracy, both methods perform similarly with values around 0.65 across 750 cell lines in 10-fold cross-validation experiments. By combining both methods it is possible to achieve 66% of correct classification rate in more than 26000 newly reported interactions comprising 11000 new compounds. A Web Service implementing the described approaches (both similarity and machine learning based models) is freely available at: http://bioquimio.udla.edu.ec/cellfishing.

Application of Bayesian statistics to estimate nitrous oxide emission factors of three nitrogen fertilisers on UK grasslands.

Trapezoidal integration by linear interpolation of data points is by far the most commonly used method of cumulative flux calculations of nitrous oxide (N2O) in studies that use flux chambers; however, this method is incapable of providing accurate uncertainty estimates. A Bayesian approach was used to calculate N2O emission factors (EFs) and their associated uncertainties from flux chamber measurements made after the application of nitrogen fertilisers, in the form of ammonium nitrate (AN), urea (Ur) and urea treated with Agrotain® urease inhibitor (UI) at four grassland sites in the UK. The comparison between the cumulative fluxes estimated using the Bayesian and linear interpolation methods were broadly similar (R2 = 0.79); however, the Bayesian method was capable of providing realistic uncertainties when a limited number of data points is available. The study reports mean EF values (and 95% confidence intervals) of 0.60 ±â€¯0.63, 0.29 ±â€¯0.22 and 0.26 ±â€¯0.17% of applied N emitted as N2O for the AN, Ur and UI treatments, respectively. There was no significant difference between N2O emissions from the Ur and UI treatments. In the case of the automatic chamber data collected at one site in this study, the data did not fit the log-normal model, implying that more complex models may be needed, particularly for measurement data with high temporal resolution.

Validation of a novel integral disease index for evaluating the grade of activity in Mexican patients with ulcerative colitis: A prospective cohort study. / Validación de un nuevo índice integral de enfermedad para evaluar el grado de actividad en pacientes mexicanos con colitis ulcerosa: un estudio de cohorte prospectivo.

INTRODUCTION AND AIM: Ulcerative colitis is a chronic condition characterized by inflammation affecting the colon. To objectively and integrally measure disease activity in patients with ulcerative colitis and thus optimize pharmacologic treatment, a novel integral disease index was created that includes the clinical, biochemical, endoscopic, and histologic characteristics necessary for achieving that task. The aim of the present study was to validate the novel integral disease index in patients with ulcerative colitis. MATERIALS AND METHODS: A cohort study on a total of 222 patients with histologic confirmations of ulcerative colitis diagnosis was conducted. The variables included in the disease index were: number of bowel movements per day; values for hemoglobin, high-sensitivity C-reactive protein, and serum albumin; and endoscopic and histologic findings measured through the subscales of the Mayo and Riley scores, respectively. The data analysis was performed utilizing the STATA SE 11.1 statistics program. RESULTS: The correlation of the novel disease index was very good (r=0.817, p <.001 with the Truelove and Witts criteria and r=0.957, p <.0001 with the Mayo score, respectively). Good internal consistency was found with a Cronbach's alpha coefficient of 0.78 and an acceptable mean inter-item correlation (r=0.47, p <.05). The total efficacy of the novel index was 87.2% correctly classified patients, with an AUC according to the three scenarios described of 0.93, 0.92, and 0.96, respectively. CONCLUSIONS: The novel integral disease index (Yamamoto-Furusho Index) provides an integral view of disease activity in patients with ulcerative colitis and is useful for optimizing pharmacologic treatment.

Preoperative use of statins does not improve outcomes and development of acute renal failure after cardiac surgery. A propensity score analysis of ARIAM-Andalucía database.

BACKGROUND: Statin use prior to cardiac surgery has been reported to improve outcomes in the postoperative period because of other effects apart from decreasing lipid levels. Objective of the study was to analyse mortality and acute renal failure (ARF) during the cardiac surgery postoperative period in patients treated with or without statins. METHODS: This prospective cohort study comprised adult patients who underwent cardiac surgery at 11 institutions in the Andalusian community from March 2008 to July 2012 included in the ARIAM adult cardiac surgery project. We performed a first analysis in the whole cohort and in a second analysis statin users prior to surgery were pair matched with non-users according to their propensity score based on demographics, comorbidities, medication and surgical data. We analysed differences in outcomes, ARF, need for renal replacement therapy (RRT) and a composite end point with mortality or major morbidity in both groups. RESULTS: The study included 7276 patients, of whom 3749 were treated with statins. Overall, hospital mortality was 10.1%, 10.5% developed ARF and 2.5% required RRT. In the whole non-matched cohort, statins were associated with lower hospital mortality (OR 0.79; 95% CI, 0.67-0.93) and less ARF (OR 0.79; 95% CI, 0.68-0.93). However, after propensity score analysis in the matched cohort of 3056 patients (1528 in each group), statin use was not consistently associated with less ARF (OR 0.94; 95% CI, 0.74-1.19), hospital mortality (OR 0.83; 95% CI, 0.68-1.1) or composite outcome (OR 0.857; 95% CI, 0.723-1.015). CONCLUSION: Despite better outcomes for the statin users in the whole cohort, the matched analysis showed that statin use before cardiac surgery was not associated with a lower risk of ARF. Nor was presurgery statin use associated with lower hospital mortality.

Occurrence of eight UV filters in beaches of Gran Canaria (Canary Islands). An approach to environmental risk assessment.

Due to the growing concern about human health effects of ultraviolet (UV) radiation, the use of UV filters has increased in recent decades. Unfortunately, some common UV filters are bioaccumulated in aquatic organisms and show a potential for estrogenic activity. The aim of the present study is to determine the presence of some UV filters in the coastal waters of six beaches around Gran Canaria Island as consequence of recreational seaside activities. Eight commonly used UV filters: benzophenone-3 (BP-3), octocrylene (OC), octyl-dimethyl-PABA (OD-PABA), ethylhexyl methoxy cinnamate (EHMC), homosalate (HMS), butyl methoxydibenzoyl methane (BMDBM), 4-methylbenzylidene camphor (4-MBC) and diethylamino hydroxybenzoyl hexyl benzoate (DHHB), were monitored and, with the exception of OD-PABA, all were detected in the samples collected. 99% of the samples showed some UV filters and concentration levels reached up to 3316.7 ng/L for BP-3. Environmental risk assessment (ERA) approach showed risk quotients (RQ) higher than 10, which means that there is a significant potential for adverse effects, for 4-MBC and EHMC for those samples with highest levels of UV filters.

Continuously evaluating performance in deceased donation: the Spanish quality assurance program.

The Spanish Quality Assurance Program applied to the process of donation after brain death entails an internal stage consisting of a continuous clinical chart review of deaths in critical care units (CCUs) performed by transplant coordinators and periodical external audits to selected centers. This paper describes the methodology and provides the most relevant results of this program, with information analyzed from 206,345 CCU deaths. According to the internal audit, 2.3% of hospital deaths and 12.4% of CCU deaths in Spain yield potential donors (clinical criteria consistent with brain death). Out of the potential donors, 54.6% become actual donors, 26% are lost due to medical unsuitability, 13.3% due to refusals to donation, 3.1% due to maintenance problems and 3% due to other reasons. Although the national pool of potential donors after brain death has progressively decreased from 65.2 per million population (pmp) in 2001 to 49 pmp in 2010, the number of actual donors after brain death has remained at about 30 pmp. External audits reveal that the number of actual donors could be 21.6% higher if all potential donors were identified and preventable losses avoided. We encourage other countries to develop similar comprehensive approaches to deceased donation performance.

Cannabinoid receptor agonists modulate oligodendrocyte differentiation by activating PI3K/Akt and the mammalian target of rapamycin (mTOR) pathways.

BACKGROUND AND PURPOSE: The endogenous cannabinoid system participates in oligodendrocyte progenitor differentiation in vitro. To determine the effect of synthetic cannabinoids on oligodendrocyte differentiation, we exposed differentiating cultures of oligodendrocytes with cannabinoid CB(1), CB(2) and CB(1)/CB(2) receptor agonists and antagonists. The response of the PI3K/Akt and the mammalian target of rapamycin (mTOR) signalling pathways were studied as effectors of cannabinoid activity. EXPERIMENTAL APPROACH: Purified oligodendrocyte progenitor cells (OPC) obtained from primary mixed glial cell cultures were treated for 48 h with CB(1), CB(2) and CB(1) /CB(2) receptor agonists (ACEA, JWH133 and HU210, respectively) in the presence or absence of the antagonists AM281 (CB(1) receptor) and AM630 (CB(2) receptor). Moreover, inhibitors of the phosphatidylinositol 3-kinase (PI3K)/Akt and mTOR pathways (LY294002 and rapamycin, respectively) were used to study the involvement of these pathways on cannabinoid-induced OPC maturation. KEY RESULTS: ACEA, JWH133 and HU-210 enhanced OPC differentiation as assessed by the expression of stage specific antigens and myelin basic protein (MBP). Moreover, this effect was blocked by the CB receptor antagonists. ACEA, JWH133 and HU210 induced a time-dependent phosphorylation of Akt and mTOR, whereas the inhibitors of PI3K/Akt (LY294002) or of mTOR (rapamycin) reversed the effects of HU-210 on oligodendrocyte differentiation and kinase activation. CONCLUSIONS AND IMPLICATIONS: Activation of cannabinoid CB(1) or CB(2) receptors with selective agonists accelerated oligodendrocyte differentiation through the mTOR and Akt signalling pathways.

Endocarditis secundaria a catéter de derivación ventrículo-atrial / Secondary endocarditis to ventriculo-atrial shunt

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[Therapeutic behavior to follow in the following clinical case: treatment of type 2 diabetes]. / Conducta terapéutica en la diabetes tipo 2. Cuanto más breve, mejor.

A 62-year old woman with obesity, high blood pressure and type 2 diabetes mellitus (DM2) was referred to a Vascular Risk Unit of the Internal Medicine Department due to elevated HbA1C (8.1%) in spite of having taken metformin (850 mg/12h) and glipizide (10 mg/12 h) regularly. She tries to exercise daily (walking 30 min) and has lost weight (from 5 to 12 kg) several times, but always regains what she has lost. Furthermore, she monitors her glucose levels in fasting every two weeks and generally has between 120 and 160 mg/dL. Her high blood pressure is being treated with enalapril/HCTZ and she also takes aspirin 100mg/day and simvastatin 20 mg/day. It is seen in her family background that one brother died suddenly at 50 years of age. Her physical examination shows a BMI of 32.4 Kg/m(2), and she has no edemas in the lower limbs. Her BP is 154/82 mmHg and creatinine 0.9 mg/dL. She has no microalbuminuria and her liver function is normal. What treatment do you think would be the more appropriate? 1 - Add glitazones. 2 - Add incretin mimetics (GLP 1/ DPP-4). 3 - Slow acting insulin.

Conducta terapéutica a seguir en el siguiente caso clínico: tratamiento de la diabetes tipo 2 / Therapeutic behavior to follow in the following clinical case: treatment of type 2 diabetes

Una mujer de 62 años con obesidad, hipertensión arterial y diabetes mellitus tipo 2 es remitida a una unidad de riesgo vascular del servicio de medicina interna porque su HbA1c está elevada (8,1%) a pesar de tomar regularmente metformina (850mg/12h) y glipizida (10mg/12h). Trata de hacer ejercicio cada día (caminar 30min) y ha adelgazado (de 5 a 12kg) en varias ocasiones, pero siempre ha vuelto a ganar lo perdido. Además se controla su glucemia en ayunas cada dos semanas y suele tener entre 120 y 160mg/dl. Su hipertensión arterial está siendo tratada con enalapril/HCTZ y además toma aspirina (100mg/día) y simvastatina (20mg/día). En su historia familiar se recoge que un hermano falleció súbitamente a los 50 años. En la exploración física presenta un IMC de 32,4kg/m2 y no tiene edemas en los MMII. Su PA es de 154/82mmHg y la creatinina de 0,9mg/dl. No presenta microalbuminuria y su función hepática es normal.¿Qué tratamiento le parece a Vd. más indicado?1. Añadir glitazonas.2. Añadir incretín miméticos (GLP1/inhibidores de la DPP-4).3. Añadir insulina de acción lenta(AU)

A 62-year old woman with obesity, high blood pressure and type 2 diabetes mellitus (DM2) was referred to a Vascular Risk Unit of the Internal Medicine Department due to elevated HbA1C (8.1%) in spite of having taken metformin (850mg/12h) and glipizide (10mg/12h) regularly. She tries to exercise daily (walking 30min) and has lost weight (from 5 to 12kg) several times, but always regains what she has lost. Furthermore, she monitors her glucose levels in fasting every two weeks and generally has between 120 and 160mg/dL. Her high blood pressure is being treated with enalapril/HCTZ and she also takes aspirin 100mg/day and simvastatin 20mg/day. It is seen in her family background that one brother died suddenly at 50 years of age. Her physical examination shows a BMI of 32.4Kg/m2, and she has no edemas in the lower limbs. Her BP is 154/82mmHg and creatinine 0.9mg/dL. She has no microalbuminuria and her liver function is normal.What treatment do you think would be the more appropriate?1 - Add glitazones.2 - Add incretin mimetics (GLP 1/ DPP-4).3 - Slow acting insulin(AU)

Derrame pleural y artralgias en relación con artritis reumatoide muy evolucionada / No disponible

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An association between resistant hypertension and the null GSTM1 genotype.

Reduction in expression levels of glutathione S-transferase (GST) mu type 1 (GSTM1) in stroke-prone spontaneously hypertensive rats has recently been reported. GSTM1 genotype was evaluated in 49 patients with resistant hypertension and compared with selected patients with controlled hypertension (n=232) and healthy participants (n=110). Null GSTM1 genotype occurred more frequent in patients with resistant hypertension than those with controlled hypertension (57.1 vs 39.7%; P=0.03; RR 1.96; 95% CI 1.04-3.69) suggesting that null GSTM1 genotype may predispose to resistant hypertension.

Control de la presión arterial, concordancias y discrepancias entre diferentes métodos de medida utilizados / Agreement and disagreement between different methods of measuring blood pressure

Fundamento y objetivo. Existen diferentes instrumentospara la medida de la presión arterial, pero los resultadosno siempre son coincidentes. El objetivo delpresente trabajo es analizar la relación entre la presiónarterial clínica (PAC) y la ambulatoria obtenidacon la monitori zación ambulatoria de presión arterial(MAPA) y la automedida de la presión arterial (AMPA)y valorar el grado de concordancia y discrepancia existenteen el porcentaje de control de la presión arterialentre los diferentes métodos en pacientes hipertensos.Material y métodos. Estudio descriptivo transversal enel que se determinó la presión arterial ambulatoria a241 pacientes hipertensos mediante una MAPA y unaAMPA y se compararon con los valores de la PAC. Comocriterios de buen control se siguieron los establecidospor la Guía Europea de Hipertensión de 2007.Resultados. Los valores de PA medidos fuera de laconsulta con MAPA y con AMPA fueron inferiores alos de la consulta. Presentaban buen control de la PAel 27% con la PAC, un 56% con la segunda toma dela AMPA, un 61, 64 y 56% con la MAPA de 24 horas,en actividad y en reposo, respectivamente. Entre un23% y un 39% presentaban cifras elevadas en la consultay normales con la MAPA o con la AMPA. La concordanciavalorada con el índice de Kappa obtienevalores próximos a 0,5 o inferiores.Conclusiones. La proporción de pacientes con presiónarterial controlada con AMPA y MAPA es superior quecon PAC. El grado de concordancia entre diferentesinstrumentos valorado con el índice de Kappa fue bajo (AU)

Background and objectives. Different instruments formeasuring blood pressure yield different results. Weaimed to analyze the relation between clinical bloodpressure (CBP), ambulatory blood pressure obtainedduring ambulatory blood pressure monitoring(ABPM), and self-measurement (SM), and to evaluatethe degree of concordance between the different me -thods in hypertensive patients.Material and methods. This is a descriptive cross-sectionalstudy comparing ABPM and SM blood pressuremeasurements with CBP in 241 hypertensive patients;we used the 2007 European Guidelines on Hypertensionas criteria for good control.Results. Blood pressure measured with ABPM and SMwere lower than CBP. Blood pressure control wasgood in 27% when measured in the doctor’s office, in56% when measured for the second time using SM,and in 61%, 64%, and 56% when measured usingABPM at 24 hours, during activity, and at rest, respectively.Between 23% and 39% had high CBP but normalvalues at ABPM or SM. Kappa values of concordancewere 0,5 or lower.Conclusions. The proportion of patients with bloodpressure under control is higher with ABPM and SMthan the CBP. The degree of concordance betweenthe different methods as shown by the Kappa coefficientwas low (AU)

Síndrome de Wallemberg en paciente joven sin factores de riesgo vascular / No disponible

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