An extensional strain sensing mechanosome drives adhesion-independent platelet activation at supraphysiological hemodynamic gradients.

BACKGROUND: Supraphysiological hemodynamics are a recognized driver of platelet activation and thrombosis at high-grade stenosis and in blood contacting circulatory support devices. However, whether platelets mechano-sense hemodynamic parameters directly in free flow (in the absence of adhesion receptor engagement), the specific hemodynamic parameters at play, the precise timing of activation, and the signaling mechanism(s) involved remain poorly elucidated. RESULTS: Using a generalized Newtonian computational model in combination with microfluidic models of flow acceleration and quasi-homogenous extensional strain, we demonstrate that platelets directly mechano-sense acute changes in free-flow extensional strain independent of shear strain, platelet amplification loops, von Willebrand factor, and canonical adhesion receptor engagement. We define an extensional strain sensing "mechanosome" in platelets involving cooperative Ca2+ signaling driven by the mechanosensitive channel Piezo1 (as the primary strain sensor) and the fast ATP gated channel P2X1 (as the secondary signal amplifier). We demonstrate that type II PI3 kinase C2α activity (acting as a "clutch") couples extensional strain to the mechanosome. CONCLUSIONS: Our findings suggest that platelets are adapted to rapidly respond to supraphysiological extensional strain dynamics, rather than the peak magnitude of imposed wall shear stress. In the context of overall platelet activation and thrombosis, we posit that "extensional strain sensing" acts as a priming mechanism in response to threshold levels of extensional strain allowing platelets to form downstream adhesive interactions more rapidly under the limiting effects of supraphysiological hemodynamics.

Recent Progress in Micro- and Nanotechnology-Enabled Sensors for Biomedical and Environmental Challenges.

Micro- and nanotechnology-enabled sensors have made remarkable advancements in the fields of biomedicine and the environment, enabling the sensitive and selective detection and quantification of diverse analytes. In biomedicine, these sensors have facilitated disease diagnosis, drug discovery, and point-of-care devices. In environmental monitoring, they have played a crucial role in assessing air, water, and soil quality, as well as ensured food safety. Despite notable progress, numerous challenges persist. This review article addresses recent developments in micro- and nanotechnology-enabled sensors for biomedical and environmental challenges, focusing on enhancing basic sensing techniques through micro/nanotechnology. Additionally, it explores the applications of these sensors in addressing current challenges in both biomedical and environmental domains. The article concludes by emphasizing the need for further research to expand the detection capabilities of sensors/devices, enhance sensitivity and selectivity, integrate wireless communication and energy-harvesting technologies, and optimize sample preparation, material selection, and automated components for sensor design, fabrication, and characterization.

[Validation of the Five Facet Mindfulness Questionnaire scale in medical students and doctors in Chile]. / Validación de la escala Five Facet Mindfulness Questionnaire en estudiantes de medicina y médicos en Chile.

BACKGROUND: The increasing use of Mindfulness-based interventions requires standardized construct-based measurement instruments for clinical and research purposes. The Five Facet Mindfulness Questionnaire scale with five factors was developed in the United States and validated in Spain. There are versions of 39, 24 and 15 items (FFMQ-39, FFMQ-24 and FFMQ-15). OBJECTIVE: To validate the FFMQ-24 and FFMQ-15 scale in Chile. METHODOLOGY: Six experts performed a linguistic adaptation of the Spanish version of the FFMQ-24. The adapted instrument was applied to a sample of 795 physicians. Internal validity was analyzed by calculating Cronbach's alpha (α) and confirmatory factor analysis (CFA). Finally, 15 items were retained, and the 5-factor solution was maintained. The FFMQ-15 scale was applied to a sample of 365 medical students and analyzed by calculating (α) and CFA. The external validity of FFMQ-15 was evaluated with the Mental Health Continiuum-14 (MHC-14) scale. RESULTS: Linguistic changes were made. The CFA of FFMQ-24 obtained a lower-than-expected fit for a 5-factor solution. The (α) value varied between .68 and .86 in all dimensions. The FFMQ-15 had an adequate fit for five factors for physicians (c2 = 216.17, df = 80, p < .01; CFI = .96; TLI = .94; RMSEA = .05 [.04, .06]; SRMR = .04) and students (c2 = 163.61, df = 80, p < .01; CF = .96; TLI = .94; RMSEA = .05 [.04, .07]; SRMR = .05). External validity with MHC-14 was adequate. CONCLUSION: The FFMQ-15 scale has acceptable internal consistency and adequate internal and external validity in Chile.

[Validation of the 12 items self-compassion scale in Chile]. / Validación del instrumento Self-Compassion Scale para valoración de la autocompasión en estudiantes y médicos en Chile.

BACKGROUND: Self-compassion is understood as a mental framework when facing difficulties in life or personal insufficiency. It arises in response to the negative aspects of self-esteem. It is assessed using the 26 item and six factor Self-Compassion Scale (SCS) in the United States and Spain but not in Chile. AIM: To validate the 12-item version (SCS-12) of the self-compassion scale. MATERIAL AND METHODS: A back translation process of the original SCS-12 scale was carried out and then it was reviewed by 6 experts. The scale was applied to a sample of 359 medical students and 795 physicians. For internal validity, confirmatory factor analyses (CFA) were performed for one, two, three, and six factors. For external validity, bivariate correlations were made with variables about mental health, burnout, symptoms of depression and anxiety. Finally, a path analysis was carried out to study the relationship between the six factors and mental health. RESULTS: The CFA for the six-factor model presents the best fit for both groups of respondents (χ2 = 216.17, df = 80, p < .01; comparative fit index (CF)I = .96; Tucker-Lewis index (TL)I = .94; Root Mean Square Error of Approximation (RMSEA) = .05 [.04, .06]; Standarized Root Mean-Square(SRMR) = .04 and χ2 = 85.97, df = 39, p < .01; CFI = .97; TLI = .95; RMSEA = .06 [.04, .07]; SRMR = .04). The external validity was adequate. CONCLUSIONS: The 12-item version of the linguistically adapted Self-Compassion Scale instrument applied to medical students and physicians in Chile, had adequate internal validity and psychometric properties.

Elevated temperature may reduce functional but not taxonomic diversity of fungal assemblages on decomposing leaf litter in streams.

Mounting evidence points to a linkage between biodiversity and ecosystem functioning (B-EF). Global drivers, such as warming and nutrient enrichment, can alter species richness and composition of aquatic fungal assemblages associated with leaf-litter decomposition, a key ecosystem process in headwater streams. However, effects of biodiversity changes on ecosystem functions might be countered by the presumed high functional redundancy of fungal species. Here, we examined how environmental variables and leaf-litter traits (based on leaf chemistry) affect taxonomic and functional α- and ß-diversity of fungal decomposers. We analysed taxonomic diversity (DNA-fingerprinting profiles) and functional diversity (community-level physiological profiles) of fungal communities in four leaf-litter species from four subregions differing in stream-water characteristics and riparian vegetation. We hypothesized that increasing stream-water temperature and nutrients would alter taxonomic diversity more than functional diversity due to the functional redundancy among aquatic fungi. Contrary to our expectations, fungal taxonomic diversity varied little with stream-water characteristics across subregions, and instead taxon replacement occurred. Overall taxonomic ß-diversity was fourfold higher than functional diversity, suggesting a high degree of functional redundancy among aquatic fungi. Elevated temperature appeared to boost assemblage uniqueness by increasing ß-diversity while the increase in nutrient concentrations appeared to homogenize fungal assemblages. Functional richness showed a negative relationship with temperature. Nonetheless, a positive relationship between leaf-litter decomposition and functional richness suggests higher carbon use efficiency of fungal communities in cold waters.

Effect of oestriol gel on dyspareunia in postmenopausal women in 2 weeks of treatment: a pilot study.

This brief report evaluates the early effect of ultra-low dose 0.005% oestriol vaginal gel on dyspareunia in postmenopausal women within the first 2 weeks of treatment. This was a prospective and multicentre single-arm pilot study and the effect of the treatment on dyspareunia was evaluated by using a diary. In total 23 women and 150 coitus were studied. 8 coitus were painless in the first week and 42 during the second week (p < .0001). A reduction in pain from the baseline was seen in 116 (77.3%) out of the 150 coitus. 0.005% oestriol vaginal gel produced a rapid and progressive improvement in dyspareunia from the very first days of treatment in postmenopausal women.IMPACT STATEMENTWhat is already known on this subject? Local oestrogen therapy has shown efficacy in the treatment of genitourinary syndrome of menopause (GSM) and dyspareunia when used for a duration of greater than 3 weeks.What do the results of this study add? This study shows that the use of oestriol gel produces clinical effects from the beginning of its use, decreasing dyspareunia in postmenopausal women within just 14 days of daily use.What are the implications of these findings for clinical practice and/or further research? In cases of dyspareunia in relation to menopause, therapy with local oestrogens, in our case oestriol gel, produces an improvement from the beginning of its use. This information is clinically relevant when evaluating therapeutic options.

[Anxiety and depression among medical students during COVID-19 pandemic]. / Presencia de síntomas de ansiedad y depresión en estudiantes de medicina durante la pandemia de COVID-19.

BACKGROUND: Medical students are especially prone to anxiety and depression. AIM: To characterize the presence of anxiety and depression and their association with gender and academic year among medical students. MATERIAL AND METHODS: Standardized electronic surveys about anxiety and depression symptoms were sent to 498 medical students with a response rate of 78%. RESULTS: We analyzed 359 surveys. A mean of 11.4 points out of 27 was observed in the depression symptoms scale. Also, 23 and 10% of respondents had moderately severe or symptoms of depression, respectively. A mean of 8.9 out of 21 points in the anxiety symptoms scale was observed. Moderate or severe anxiety symptoms were present in 26 and 15% of respondents, respectively. Women and preclinical students had higher depression and anxiety scores. CONCLUSIONS: A high presence of anxiety and depression symptoms was characterized among medical students during the pandemic. Preclinical students and women had higher scores in both scales.

A nonhuman primate model of blue light-induced progressive outer retina degeneration showing brimonidine drug delivery system-mediated cyto- and neuroprotection.

Geographic atrophy (GA) is an advanced form of age-related macular degeneration (AMD) characterized by atrophy of the retinal pigment epithelium (RPE), loss of photoreceptors, and disruption of choriocapillaris. Excessive light exposure is toxic to the retina and is a known risk factor for AMD. We first investigated the effects of blue light-induced phototoxicity on RPE and photoreceptors in nonhuman primates (NHPs, a model of progressive retinal degeneration) and then evaluated the potential cyto- and neuroprotective effects of the brimonidine drug delivery system (Brimo DDS). In the first set of experiments related to model development, parafoveal lesions of varying severity were induced using blue light irradiation of the retina of cynomolgus monkeys to evaluate the level of phototoxicity in the RPE and photoreceptors. RPE damage was assessed using fundus autofluorescence imaging to quantify areas of hypofluorescence, while thinning of the outer nuclear layer (ONL, photoreceptor nuclei) was quantified using optical coherence tomography (OCT). Photoreceptor function was assessed using multifocal electroretinography (mfERG). RPE damage progressively increased across all lesion severities from 2 to 12 weeks, as did the extent of ONL thinning. Lesions of high severity continued to show reduction in mfERG amplitude, reaching a statistically significant maximum reduction at 12 weeks. Collectively, the first set of experiments showed that blue light irradiation of the NHP eye resulted in progressive retinal degeneration identified by damage to RPE, ONL thinning, and disrupted photoreceptor function - hallmarks of GA in humans. We then used the model to evaluate the cyto- and neuroprotective effects of Brimo DDS, administered as a therapeutic after allowing the lesions to develop for 5 weeks. Placebo DDS or Brimo DDS were administered intravitreally and a set of untreated animals were used as an additional control. In the placebo DDS group, hypofluorescence area continued to increase from baseline, indicating progressive RPE damage, while progression was significantly slowed in eyes receiving Brimo DDS. Likewise, ONL thinning continued to progress over time in eyes that received the placebo DDS, but was reduced in Brimo DDS-treated eyes. Pharmacologically relevant brimonidine concentrations were sustained in the retina for up to 26 weeks following Brimo DDS administration. In summary, Brimo DDS demonstrated cyto- and neuroprotective effects in a novel NHP GA model of progressive retinal degeneration.

PHASE 2 STUDY OF THE SAFETY AND EFFICACY OF BRIMONIDINE DRUG DELIVERY SYSTEM (BRIMO DDS) GENERATION 1 IN PATIENTS WITH GEOGRAPHIC ATROPHY SECONDARY TO AGE-RELATED MACULAR DEGENERATION.

PURPOSE: To evaluate the safety and efficacy of Brimonidine Drug Delivery System (Brimo DDS), a biodegradable intravitreal implant, in the treatment of geographic atrophy (GA) secondary to age-related macular degeneration. METHODS: Phase 2, randomized, multicenter, double-masked, 24-month study. Study eyes were treated (Day 1; Month 6 retreatment) with Brimo DDS 132 µg (n = 49), Brimo DDS 264 µg (n = 41), or sham procedure (n = 23). The primary timepoint for efficacy analysis was Month 12. RESULTS: Mean GA area growth at Month 12 was 1.78 mm2, 1.59 mm2, and 2.19 mm2 in the Brimo DDS 132 µg, 264 µg, and sham groups, respectively. Geographic atrophy area growth was consistently smaller with Brimo DDS 132 and 264 µg than sham; between-group differences were significant (P ≤ 0.032) at Month 3. In patients with baseline lesion area ≥6 mm2 (two-thirds of patients), GA lesion area and effective radius growth was reduced with Brimo DDS 132 and 264 µg at Month 12 (P ≤ 0.050 vs. sham). Treatment-related adverse events were usually injection procedure-related. CONCLUSION: Brimo DDS demonstrated a favorable safety profile and reduced GA lesion area growth at Month 3. Lesion growth at Month 12 was reduced in patients with baseline GA lesion area ≥6 mm2. The results support Phase 3 development.

Extremely Sensitive Microwave Microfluidic Dielectric Sensor Using a Transmission Line Loaded with Shunt LC Resonators.

In this paper, a very high sensitivity microwave-based planar microfluidic sensor is presented. Sensitivity enhancement is achieved and described theoretically and experimentally by eliminating any extra parasitic capacitance not contributing to the sensing mechanism. The sensor consists of a microstrip transmission line loaded with a series connected shunt LC resonator. A microfluidic channel is attached to the area of the highest electric field concentration. The electric field distribution and, therefore, the resonance characteristics are modified by applying microfluidic dielectric samples to the sensing area. The sensor performance and working principle are described through a circuit model analysis. A device prototype is fabricated, and experimental measurements using water/ethanol and water/methanol solutions are presented for validation of the sensing mathematical model.

Adherence to a priori dietary indexes and baseline prevalence of cardiovascular risk factors in the PREDIMED-Plus randomised trial.

PURPOSE: Cardiovascular disease remains the global leading cause of death. We evaluated at baseline the association between the adherence to eight a priori high-quality dietary scores and the prevalence of individual and clustered cardiovascular risk factors (CVRF) in the PREDIMED-Plus cohort. METHODS: All PREDIMED-Plus participants (6874 men and women aged 55-75 years, with overweight/obesity and metabolic syndrome) were assessed. The prevalence of 4 CVRF (hypertension, obesity, diabetes, and dyslipidaemia), using standard diagnoses criteria, were considered as outcomes. The adherence to eight a priori-defined dietary indexes was calculated. Multivariable models were fitted to estimate differences in mean values of factors and prevalence ratios for individual and clustered CVRF. RESULTS: Highest conformity to any dietary pattern did not show inverse associations with hypertension. The modified Mediterranean Diet Score (PR = 0.95; 95% CI 0.90-0.99), Mediterranean Diet Adherence Score (MEDAS) (PR = 0.94; 95% CI 0.89-0.98), the pro-vegetarian dietary pattern (PR = 0.95; 95% CI 0.90-0.99) and the Alternate Healthy Eating Index 2010 (PR = 0.92; 95% CI 0.87-0.96) were inversely associated with prevalence of obesity. We identified significant inverse trend among participants who better adhered to the MEDAS and the Prime Diet Quality Score (PDQS) in the mean number of CVRF across categories of adherence. Better adherence to several high-quality dietary indexes was associated with better blood lipid profiles and anthropometric measures. CONCLUSIONS: Highest adherence to dietary quality indexes, especially Mediterranean-style and PDQS scores, showed marginal associations with lower prevalence of individual and clustered CVRF among elderly adults with metabolic syndrome at high risk of cardiovascular disease.

Antimicrobial resistance. Its importance and efforts to control it.

The World Health Organization estimates that bacterial resistance will cause 10 million deaths by 2050. As part of the Global Action Plan on Antimicrobial Resistance, it proposed networks of specialized laboratories in order to preserve strains and optimize the use of antimicrobials. That is the case of the Latin American Surveillance Network of Antimicrobials Resistance. In a 2019 study, the main bacteria of the ESKAPE group (which are highly resistant to the most widely used antibiotics) that cause infections in Mexican Hospitals were identified to be multidrug-resistant (MDR) and extended-spectrum beta-lactamase (ESBL)-producing Klebsiella spp., ESBL-producing Enterobacter spp., Acinetobacter baumannii, MDR Pseudomonas aeruginosa, methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus faecium. With information on drug resistance, regimens are recommended to treat infection caused by Helicobacter pylori, a pathogen related to the development of cancer and whose prevalence in the adult population of Latin America is estimated to range between 60 and 70 %.

La Organización Mundial de la Salud estima que en 2050 la resistencia bacteriana ocasionará 10 millones de muertes. Como parte del Plan de Acción Mundial sobre la Resistencia a los Antimicrobianos propuso redes de laboratorios especializados, para conservar cepas y optimizar el uso de los antimicrobianos. En un estudio de 2019 se identificó que las principales bacterias del grupo ESKAPE (con alta resistencia a los antibióticos más usados) que causan infecciones en hospitales de México son Klebsiella spp. resistentes a múltiples fármacos (MDR) y productoras de betalactamasa de espectro extendido (BLEE), Enterobacter spp. BLEE, Acinetobacter baumannii, Pseudomonas aeruginosa MDR, Staphylococcus aureus meticilinorresistente y Enterococcus faecium resistente a vancomicina. Con la información de resistencia a los fármacos se recomiendan esquemas para tratar la infección causada por Helicobacter pylori, relacionado con el desarrollo de cáncer y cuya prevalencia en la población adulta de Latinoamérica se estima es de entre 60 y 70 %.

PyCellBase, an efficient python package for easy retrieval of biological data from heterogeneous sources.

BACKGROUND: Biological databases and repositories are incrementing in diversity and complexity over the years. This rapid expansion of current and new sources of biological knowledge raises serious problems of data accessibility and integration. To handle the growing necessity of unification, CellBase was created as an integrative solution. CellBase provides a centralized NoSQL database containing biological information from different and heterogeneous sources. Access to this information is done through a RESTful web service API, which provides an efficient interface to the data. RESULTS: In this work we present PyCellBase, a Python package that provides programmatic access to the rich RESTful web service API offered by CellBase. This package offers a fast and user-friendly access to biological information without the need of installing any local database. In addition, a series of command-line tools are provided to perform common bioinformatic tasks, such as variant annotation. CellBase data is always available by a high-availability cluster and queries have been tuned to ensure a real-time performance. CONCLUSION: PyCellBase is an open-source Python package that provides an efficient access to heterogeneous biological information. It allows to perform tasks that require a comprehensive set of knowledge resources, as for example variant annotation. Queries can be easily fine-tuned to retrieve the desired information of particular biological features. PyCellBase offers the convenience of an object-oriented scripting language and provides the ability to integrate the obtained results into other Python applications and pipelines.

Lipoprotein-associated phospholipase A2 (Lp-PLA2) as a therapeutic target to prevent retinal vasopermeability during diabetes.

Lipoprotein-associated phospholipase A2 (Lp-PLA2) hydrolyses oxidized low-density lipoproteins into proinflammatory products, which can have detrimental effects on vascular function. As a specific inhibitor of Lp-PLA2, darapladib has been shown to be protective against atherogenesis and vascular leakage in diabetic and hypercholesterolemic animal models. This study has investigated whether Lp-PLA2 and its major enzymatic product, lysophosphatidylcholine (LPC), are involved in blood-retinal barrier (BRB) damage during diabetic retinopathy. We assessed BRB protection in diabetic rats through use of species-specific analogs of darapladib. Systemic Lp-PLA2 inhibition using SB-435495 at 10 mg/kg (i.p.) effectively suppressed BRB breakdown in streptozotocin-diabetic Brown Norway rats. This inhibitory effect was comparable to intravitreal VEGF neutralization, and the protection against BRB dysfunction was additive when both targets were inhibited simultaneously. Mechanistic studies in primary brain and retinal microvascular endothelial cells, as well as occluded rat pial microvessels, showed that luminal but not abluminal LPC potently induced permeability, and that this required signaling by the VEGF receptor 2 (VEGFR2). Taken together, this study demonstrates that Lp-PLA2 inhibition can effectively prevent diabetes-mediated BRB dysfunction and that LPC impacts on the retinal vascular endothelium to induce vasopermeability via VEGFR2. Thus, Lp-PLA2 may be a useful therapeutic target for patients with diabetic macular edema (DME), perhaps in combination with currently administered anti-VEGF agents.

Perampanel in routine clinical use in idiopathic generalized epilepsy: The 12-month GENERAL study.

OBJECTIVE: To analyze the effectiveness and tolerability of perampanel across different seizure types in routine clinical care of patients with idiopathic generalized epilepsy (IGE). METHODS: This multicenter, retrospective, 1-year observational study collected data from patient records at 21 specialist epilepsy units in Spain. All patients who were aged ≥12 years, prescribed perampanel before December 2016, and had a confirmed diagnosis of IGE were included. RESULTS: The population comprised 149 patients with IGE (60 with juvenile myoclonic epilepsy, 51 generalized tonic-clonic seizures [GTCS] only, 21 juvenile absence epilepsy, 10 childhood absence epilepsy, 6 adulthood absence epilepsy, and one Jeavons syndrome). Mean age was 36 years. The retention rate at 12 months was 83% (124/149), and 4 mg was the most common dose. At 12 months, the seizure-free rate was 59% for all seizures (88/149); 63% for GTCS (72/115), 65% for myoclonic seizures (31/48), and 51% for absence seizures (24/47). Seizure frequency was reduced significantly at 12 months relative to baseline for GTCS (78%), myoclonic (65%), and absence seizures (48%). Increase from baseline seizure frequency was seen in 5.2% of patients with GTCS seizures, 6.3% with myoclonic, and 4.3% with absence seizures. Perampanel was effective regardless of epilepsy syndrome, concomitant antiepileptic drugs (AEDs), and prior AEDs, but retention and seizure freedom were significantly higher when used as early add-on (after ≤2 prior AEDs) than late (≥3 prior AEDs). Adverse events were reported in 50% of patients over 12 months, mostly mild or moderate, and irritability (23%), somnolence (15%), and dizziness (14%) were most frequent. SIGNIFICANCE: In routine clinical care of patients with IGE, perampanel improved seizure outcomes for GTCS, myoclonic seizures, and absence seizures, with few discontinuations due to adverse events. This is the first real-world evidence with perampanel across different seizure types in IGE.

Variables Influencing the Accuracy of 3D Modeling of Existing Roads Using Consumer Cameras in Aerial Photogrammetry.

Point cloud (PC) generation from photogrammetry⁻remotely piloted aircraft systems (RPAS) at high spatial and temporal resolution and accuracy is of increasing importance for many applications. For several years, photogrammetry⁻RPAS has been used to recover civil engineering works such as digital elevation models (DEMs), triangle irregular networks (TINs), contour levels, orthophotographs, etc. This study analyzes the influence of variables involved in the accuracy of PC generation over asphalt shapes and determines the most influential variable based on the development of an artificial neural network (ANN) with patterns identified in the test flights. The input variables were those involved, and output was the three-dimension root mean square error (3D-RMSE) of the PC in each ground control point (GCP). The result of the study shows that the most influential variable over PC accuracy is the modulation transfer function 50 (MTF50). In addition, the study obtained an average 3D-RMSE of 1 cm. The results can be used by the scientific and civil engineering communities to consider MTF50 variables in obtaining images from RPAS cameras and to predict the accuracy of a PC over asphalt based on the ANN developed. Also, this ANN could be the beginning of a large database containing patterns from several cameras and lenses in the world market.

Shear stress mediates exocytosis of functional TRPV4 channels in endothelial cells.

Mechanosensitive ion channels are implicated in the biology of touch, pain, hearing and vascular reactivity; however, the identity of these ion channels and the molecular basis of their activation is poorly understood. We previously found that transient receptor potential vanilloid 4 (TRPV4) is a receptor operated ion channel that is sensitised and activated by mechanical stress. Here, we investigated the effects of mechanical stimulation on TRPV4 localisation and activation in native and recombinant TRPV4-expressing cells. We used a combination of total internal reflection fluorescence microscopy, cell surface biotinylation assay and Ca(2+) imaging with laser scanning confocal microscope to show that TRPV4 is expressed in primary vascular endothelial cells and that shear stress sensitises the response of TRPV4 to its agonist, GSK1016790A. The sensitisation was attributed to the recruitment of intracellular pools of TRPV4 to the plasma membrane, through the clathrin and dynamin-mediated exocytosis. The translocation was dependent on ILK/Akt signalling pathway, release of Ca(2+) from intracellular stores and we demonstrated that shear stress stimulated phosphorylation of TRPV4 at tyrosine Y110. Our findings implicate calcium-sensitive TRPV4 translocation in the regulation of endothelial responses to mechanical stimulation.

Previously acquired cue-outcome structural knowledge guides new learning: Evidence from the retroactive-interference-between-cues effect.

The effect of retroactive interference between cues predicting the same outcome (RIBC) occurs when the behavioral expression of a cue-outcome association (e.g., A→O1) is reduced due to the later acquisition of an association between a different cue and the same outcome (e.g., B→O1). In the present experimental series, we show that this effect can be modulated by knowledge concerning the structure of these cue-outcome relationships. In Experiments 1A and 1B, a pretraining phase was included to promote the expectation of either a one-to-one (OtO) or a many-to-one (MtO) cue-outcome structure during the subsequent RIBC training phases. We hypothesized that the adoption of an OtO expectation would make participants infer that the previously learned A→O1 relationship would not hold any longer after the exposure to B→O1 trials. Alternatively, the adoption of an MtO expectation would prevent participants from making such an inference. Experiment 1B included an additional condition without pretraining, to assess whether the OtO structure was expected by default. Experiment 2 included control conditions to assess the RIBC effect and induced the expectation of an OtO or MtO structure without the addition of a pretraining phase. Overall, the results suggest that participants effectively induced structural expectations regarding the cue-outcome contingencies. In turn, these expectations may have potentiated (OtO expectation) or alleviated (MtO expectation) the RIBC effect, depending on how well these expectations could accommodate the target A→O1 test association. This pattern of results poses difficulties for current explanations of the RIBC effect, since these explanations do not consider the incidence of cue-outcome structural expectations.

Successful treatment of infertility in a female Sumatran orangutan Pongo abelii.

In 2011, a female Sumatran orangutan housed at Durrell Wildlife Conservation Trust became infertile following a massive antepartum hemorrhage in labor and the delivery of a stillborn infant. The placenta was infected with Pantoea sp. Hysterosalpingography (HSG) revealed blocked fallopian tubes, and pressurized fallopian tube perfusion was used to reverse the tubal occlusion. She subsequently conceived and following an intensive training program, we were able to measure umbilical artery waveform analysis for fetal well-being and placental localization to exclude placenta previa, which could complicate pregnancy and lead to catastrophic hemorrhage. The female went on to deliver a healthy offspring. We suggest that these techniques should be considered for other infertile females in the global captive population.

An automated Y-maze based on a reduced instruction set computer (RISC) microcontroller for the assessment of continuous spontaneous alternation in rats.

Continuous spontaneous alternation behavior (SAB) in a Y-maze is used for evaluating working memory in rodents. Here, the design of an automated Y-maze equipped with three infrared optocouplers per arm, and commanded by a reduced instruction set computer (RISC) microcontroller is described. The software was devised for recording only true entries and exits to the arms. Experimental settings are programmed via a keyboard with three buttons and a display. The sequence of arm entries and the time spent in each arm and the neutral zone (NZ) are saved as a text file in a non-volatile memory for later transfer to a USB flash memory. Data files are analyzed with a program developed under LabVIEW® environment, and the results are exported to an Excel® spreadsheet file. Variables measured are: latency to exit the starting arm, sequence and number of arm entries, number of alternations, alternation percentage, and cumulative times spent in each arm and NZ. The automated Y-maze accurately detected the SAB decrease produced in rats by the muscarinic antagonist trihexyphenidyl, and its reversal by caffeine, having 100 % concordance with the alternation percentages calculated by two trained observers who independently watched videos of the same experiments. Although the values of time spent in the arms and NZ measured by the automated system had small discrepancies with those calculated by the observers, Bland-Altman analysis showed 95 % concordance in three pairs of comparisons, while in one it was 90 %, indicating that this system is a reliable and inexpensive alternative for the study of continuous SAB in rodents.