La colonoscopia (CS) es una técnica invasiva, fundamental para el estudio del colon. Es un procedimiento seguro y bien tolerado. Sin embargo, en personas de edad avanzada o con fragilidad (PEA/F) aumenta el riesgo de acontecimientos adversos, preparación insuficiente o exploraciones incompletas. El objetivo de este documento de posicionamiento fue consensuar recomendaciones sobre valoración del riesgo, indicaciones y cuidados especiales necesarios para la CS en PEA/F. El documento fue redactado por un grupo de expertos designados por la SCD, la SCGiG y la CAMFiC entre 2020 y 2022. Se consensuaron 8 afirmaciones y recomendaciones, entre ellas: no realizar CS a los pacientes con fragilidad avanzada, indicar CS solo si los beneficios son claramente superiores a los riesgos en fragilidad moderada, no repetir CS en PEA/F que tienen una CS completa previa sin lesiones y no indicar CS de cribado en pacientes con fragilidad moderada o avanzada (AU)
Colonoscopy (CS) is an invasive diagnostic and therapeutic technique, allowing the study of the colon. It is a safe and well tolerated procedure. However, CS is associated with an increased risk of adverse events, insufficient preparation and incomplete examinations in the elderly or frail patient (PEA/F). The objective of this position paper was to develop a set of recommendations on risk assessment, indications and special care required for CS in the PEA/F. It was drafted by a group of experts appointed by the SCD, SCGiG and CAMFiC that agreed on eight statements and recommendations, between them to recommend against performing CS in patients with advanced frailty, to indicate CS only if the benefits clearly outweigh the risks in moderate frailty and to avoid repeating CS in patients with a previous normal procedure. We also recommended against performing screening CS in patients with moderate or advanced frailty (AU)
Humans , Aged , Aged, 80 and over , Colonoscopy/adverse effects , Colonoscopy/methods , Frail Elderly , Societies, Medical , Risk Factors , Spain
Colonoscopy (CS) is an invasive diagnostic and therapeutic technique, allowing the study of the colon. It is a safe and well tolerated procedure. However, CS is associated with an increased risk of adverse events, insufficient preparation and incomplete examinations in the elderly or frail patient (PEA/F). The objective of this position paper was to develop a set of recommendations on risk assessment, indications and special care required for CS in the PEA/F. It was drafted by a group of experts appointed by the SCD, SCGiG and CAMFiC that agreed on eight statements and recommendations, between them to recommend against performing CS in patients with advanced frailty, to indicate CS only if the benefits clearly outweigh the risks in moderate frailty and to avoid repeating CS in patients with a previous normal procedure. We also recommended against performing screening CS in patients with moderate or advanced frailty.
Frailty , Humans , Aged , Frailty/diagnosis , Frail Elderly , Colonoscopy/methods , Risk Assessment
CHIR99021, also known as laduviglusib or CT99021, is a Glycogen-synthase kinase 3ß (GSK3ß) inhibitor, which has been reported as a promising drug for cardiomyocyte regeneration or treatment of sensorial hearing loss. Since the activation of dopamine (DA) receptors regulates dopamine synthesis and they can signal through the ß-arrestin pathway and GSK3ß, we decided to check the effect of GSK3ß inhibitors (CHIR99021, SB216763 and lithium ion) on the control of DA synthesis. Using ex vivo experiments with minces from rat brain striatum, we observed that CHIR99021, but not SB216763 or lithium, causes complete abrogation of both DA synthesis and accumulation, pointing to off-target effects of CHIR99021. This decrease can be attributed to tyrosine hydroxylase (TH) inhibition since the accumulation of l-DOPA in the presence of a DOPA decarboxylase inhibitor was similarly decreased. On the other hand, CHIR99021 caused a dramatic increase in the DOPAC/DA ratio, an indicator of DA metabolization, and hindered DA incorporation into striatum tissue. Tetrabenazine, an inhibitor of DA vesicular transport, also caused DA depletion and DOPAC/DA ratio increase to the same extent as CHIR99021. In addition, both CHIR99021 or SB216763, but not lithium, decreased TH phosphorylation in Ser19, but not in Ser31 or Ser40. These results demonstrate that CHIR99021 can lead to TH inactivation and DA depletion in brain striatum, opening the possibility of its use in DA-related disorders, and shows effects to be considered in future clinical trials. More work is needed to find the mechanism exerted by CHIR99021 on DA accumulation.
Corpus Striatum , Dopamine , Tyrosine 3-Monooxygenase , Animals , Rats , 3,4-Dihydroxyphenylacetic Acid/metabolism , Corpus Striatum/enzymology , Dopamine/metabolism , Glycogen Synthase Kinase 3 beta/metabolism , Lithium/pharmacology , Tyrosine 3-Monooxygenase/antagonists & inhibitors
BACKGROUND: Gene set enrichment analysis (detecting phenotypic terms that emerge as significant in a set of genes) plays an important role in bioinformatics focused on diseases of genetic basis. To facilitate phenotype-oriented gene set analysis, we developed PhenoExam, a freely available R package for tool developers and a web interface for users, which performs: (1) phenotype and disease enrichment analysis on a gene set; (2) measures statistically significant phenotype similarities between gene sets and (3) detects significant differential phenotypes or disease terms across different databases. RESULTS: PhenoExam generates sensitive and accurate phenotype enrichment analyses. It is also effective in segregating gene sets or Mendelian diseases with very similar phenotypes. We tested the tool with two similar diseases (Parkinson and dystonia), to show phenotype-level similarities but also potentially interesting differences. Moreover, we used PhenoExam to validate computationally predicted new genes potentially associated with epilepsy. CONCLUSIONS: We developed PhenoExam, a freely available R package and Web application, which performs phenotype enrichment and disease enrichment analysis on gene set G, measures statistically significant phenotype similarities between pairs of gene sets G and G' and detects statistically significant exclusive phenotypes or disease terms, across different databases. We proved with simulations and real cases that it is useful to distinguish between gene sets or diseases with very similar phenotypes. Github R package URL is https://github.com/alexcis95/PhenoExam . Shiny App URL is https://alejandrocisterna.shinyapps.io/phenoexamweb/ .
Computational Biology , Software , Databases, Factual , Phenotype , Databases, Genetic
Synaptic events are important to define treatment strategies for brain disorders. In the present paper, freshly obtained rat brain striatal minces were incubated under different times and conditions to determine dopamine biosynthesis, storage, and tyrosine hydroxylase phosphorylation. Remarkably, we found that endogenous dopamine spontaneously accumulated during tissue incubation at 37 °C ex vivo while dopamine synthesis simultaneously decreased. We analyzed whether these changes in brain dopamine biosynthesis and storage were linked to dopamine feedback inhibition of its synthesis-limiting enzyme tyrosine hydroxylase. The aromatic-l-amino-acid decarboxylase inhibitor NSD-1015 prevented both effects. As expected, dopamine accumulation was increased with l-DOPA addition or VMAT2-overexpression, and dopamine synthesis decreased further with added dopamine, the VMAT2 inhibitor tetrabenazine or D2 auto-receptor activation with quinpirole, accordingly to the known synaptic effects of these treatments. Phosphorylation activation and inhibition of tyrosine hydroxylase on Ser31 and Ser40 with okadaic acid, Sp-cAMP and PD98059 also exerted the expected effects. However, no clear-cut association was found between dopamine feedback inhibition of its own biosynthesis and changes of tyrosine hydroxylase phosphorylation, assessed by Western blot and mass spectrometry. The later technique also revealed a new Thr30 phosphorylation in rat tyrosine hydroxylase. Our methodological assessment of brain dopamine synthesis and storage dynamics ex vivo could be applied to predict the in vivo effects of pharmacological interventions in animal models of dopamine-related disorders.
Dopamine , Tyrosine 3-Monooxygenase , Animals , Brain/metabolism , Corpus Striatum , Dopamine/pharmacology , Feedback , Rats , Tyrosine 3-Monooxygenase/metabolism
BACKGROUND: Universal vaccination for hepatitis B virus (HBV) and migratory movements have changed the demographic characteristics of this disease in Spain and in Europe. Therefore, we evaluated the characteristics of the disease and the possible differences according to origin (immigrants vs non-immigrants) and access to treatment. METHODS: This is a multicenter cross-sectional study (June 2014 to May 2015) in which outpatients with a positive HBsAg were seen and followed in four Hepatology units. Demographic and clinical data and indication and access to treatment were collected in two different regions of Catalonia (Spain) where there are no barriers to treatment due to a comprehensive coverage under the National Health System. RESULTS: A total of 951 patients were evaluated (48.1% men). Of these, 46.6% were immigrants (58.7% of them were born in Africa) and were significantly younger compared to non-immigrants. The proportions of patients with alcohol consumption, being overweight, and other indicators of metabolic co-morbidities were significantly higher in non-immigrants. Among the 937 patients receiving HBeAg examination, 91.7% were HBeAg-negative. Chronic HBeAg-positive infection was significantly higher in immigrants (3.9% vs 0.6%, P = 0.001) and chronic HBeAg-negative hepatitis was higher non-immigrants (31.7% vs 21.4%, P < 0.001). Not only was the proportion of patients who met treatment criteria significantly higher among non-immigrants (38.4% vs 29.2%, P = 0.003), but also the proportion of those with indication of effectively receiving therapy at the time of data collection (83.2% vs 57.8 %, P < 0.001). CONCLUSIONS: The immigrant population with HBV is younger and has a lower prevalence of metabolic co-morbidities and a higher frequency of chronic HBeAg infection. Despite having access to care and an indication for treatment, some do not get adequately treated due to several factors including local adaptation that precludes access to treatment.
The increase of Software Defined Networks (SDN) and Network Function Virtualization (NFV) technologies is bringing many security management benefits that can be exploited at the edge of Internet of Things (IoT) networks to deal with cyber-threats. In this sense, this paper presents and evaluates a novel policy-based and cyber-situational awareness security framework for continuous and dynamic management of Authentication, Authorization, Accounting (AAA) as well as Channel Protection virtual security functions in IoT networks enabled with SDN/NFV. The virtual AAA, including network authenticators, are deployed as VNF (Virtual Network Function) dynamically at the edge, in order to enable scalable device's bootstrapping and managing the access control of IoT devices to the network. In addition, our solution allows distributing dynamically the necessary crypto-keys for IoT Machine to Machine (M2M) communications and deploy virtual Channel-protection proxys as VNFs, with the aim of establishing secure tunnels among IoT devices and services, according to the contextual decisions inferred by the cognitive framework. The solution has been implemented and evaluated, demonstrating its feasibility to manage dynamically AAA and channel protection in SDN/NFV-enabled IoT scenarios.
BACKGROUND AND AIM: Drug-eluting bead transarterial chemoembolization (DEB-TACE) improves the survival of patients with hepatocellular carcinoma (HCC), intermediate stage [i.e. Barcelona Clinic Liver Cancer-B (BCLC-B)]. The aim of our study was to analyse the overall survival (OS) and prognostic factors of patients with HCC treated with DEB-TACE. PATIENTS AND METHODS: Patients' clinical course was recorded from January 2005 to July 2014. The median OS was obtained by the Kaplan-Meier method and compared using the log-rank test. The prognosis factors associated with OS were determined by a multivariate Cox regression analysis and the accuracy of the OS prediction was determined by calculation of the assessment for retreatment with TACE score (ART score). RESULTS: A cohort of 147 consecutive patients treated with DEB-TACE was included. Median age of the patients was 73.4 years. Overall, 68.7% were men, and all had cirrhosis, with 68.8% being hepatisis C virus positive. Moreover, 35.2% were staged as BCLC-A and 60.2% as BCLC-B. After a median follow-up of 19.2 months, 29.3% were alive, 4.3% needed treatment with sorafenib and 56.1% underwent DEB-TACE retreatment. Median OS was 22.8 [95% confidence interval (CI)=19.6-25.9]. After censoring for ascites and more than one nodule, OS was 23.87 (95% CI =20.72-27.01) and 26.89 (95% CI =21.00-32.78), respectively. The risk of death decreased by 22.3% with the number of DEB-TACE sessions (hazard ratio=0.777) and increased by 25.9% with higher Child-Pugh score (hazard ratio=1.259). Overall, 61.2% of the cohort had an ART score between 0 and 1.5. There were no statistical differences in OS between cohort groups with ART of 0-1.5 and at least 2.5. CONCLUSION: The results validate the efficacy and safety of DEB-TACE in patients with HCC and the importance of some prognostic factors for patient survival.
Carcinoma, Hepatocellular/therapy , Chemoembolization, Therapeutic/methods , Liver Neoplasms/therapy , Aged , Antibiotics, Antineoplastic/administration & dosage , Antibiotics, Antineoplastic/adverse effects , Chemoembolization, Therapeutic/adverse effects , Doxorubicin/administration & dosage , Doxorubicin/adverse effects , Female , Follow-Up Studies , Humans , Kaplan-Meier Estimate , Male , Microspheres , Prognosis , Risk Assessment/methods , Treatment Outcome
The probability of growth and aflatoxin B1 (AFB1) production of 20 isolates of Aspergillus flavus were studied using a full factorial design with eight water activity levels (0.84-0.98 aw) and six temperature levels (15-40 °C). Binary data obtained from growth studies were modelled using linear logistic regression analysis as a function of temperature, water activity and time for each isolate. In parallel, AFB1 was extracted at different times from newly formed colonies (up to 20 mm in diameter). Although a total of 950 AFB1 values over time for all conditions studied were recorded, they were not considered to be enough to build probability models over time, and therefore, only models at 30 days were built. The confidence intervals of the regression coefficients of the probability of growth models showed some differences among the 20 growth models. Further, to assess the growth/no growth and AFB1/no- AFB1 production boundaries, 0.05 and 0.5 probabilities were plotted at 30 days for all of the isolates. The boundaries for growth and AFB1 showed that, in general, the conditions for growth were wider than those for AFB1 production. The probability of growth and AFB1 production seemed to be less variable among isolates than AFB1 accumulation. Apart from the AFB1 production probability models, using growth probability models for AFB1 probability predictions could be, although conservative, a suitable alternative. Predictive mycology should include a number of isolates to generate data to build predictive models and take into account the genetic diversity of the species and thus make predictions as similar as possible to real fungal food contamination.
Aflatoxin B1/metabolism , Aspergillus flavus/classification , Aspergillus flavus/growth & development , Aspergillus flavus/metabolism , Food Contamination/analysis , Linear Models , Models, Statistical , Species Specificity , Temperature , Water/analysis
Early life stress (ELS) induces long-term effects in later functioning and interacts with further exposure to other stressors in adulthood to shape our responsiveness to reward-related cues. The attribution of incentive salience to food-related cues may be modulated by previous and current exposures to stressors in a sex-dependent manner. We hypothesized from human data that exposure to a traumatic (severe) adult stressor will decrease the attribution of incentive salience to reward-associated cues, especially in females, because these effects are modulated by previous ELS. To study these factors in Long-Evans rats, we used as an ELS model of restriction of nesting material and concurrently evaluated maternal care. In adulthood, the offspring of both sexes were exposed to acute immobilization (IMO), and several days after, a Pavlovian conditioning procedure was used to assess the incentive salience of food-related cues. Some rats developed more attraction to the cue predictive of reward (sign-tracking) and others were attracted to the location of the reward itself, the food-magazine (goal-tracking). Several dopaminergic markers were evaluated by in situ hybridization. The results showed that ELS increased maternal care and decreased body weight gain (only in females). Regarding incentive salience, in absolute control animals, females presented slightly greater sign-tracking behavior than males. Non-ELS male rats exposed to IMO showed a bias towards goal-tracking, whereas in females, IMO produced a bias towards sign-tracking. Animals of both sexes not exposed to IMO displayed an intermediate phenotype. ELS in IMO-treated females was able to reduce sign-tracking and decrease tyrosine hydroxylase expression in the ventral tegmental area and dopamine D1 receptor expression in the accumbens shell. Although the predicted greater decrease in females in sign-tracking after IMO exposure was not corroborated by the data, the results highlight the idea that sex is an important factor in the study of the long-term impact of early and adult stressors.
Immobilization , Motivation , Stress, Physiological , Animals , Behavior, Animal , Biomarkers/metabolism , Dopamine/metabolism , Female , Male , Rats , Rats, Long-Evans
Database URL: http://www.psygenet.org. PsyGeNET corpus: http://www.psygenet.org/ds/PsyGeNET/results/psygenetCorpus.tar.
Data Curation/methods , Data Mining/methods , Databases, Genetic , Mental Disorders/genetics , Software , Humans
Background: Cocaine addiction continues to be a major heath concern, and despite public health intervention there is a lack of efficient pharmacological treatment options. A newly identified potential target are the group I metabotropic glutamate receptors, with allosteric modulators showing particular promise. Methods: We evaluated the capacity of group I metabotropic glutamate receptors to induce functional responses in ex vivo striatal slices from rats with (1) acute cocaine self-administration, (2) chronic cocaine self-administration, and (3) 60 days cocaine self-administration withdrawal by Western blot and extracellular recordings of synaptic transmission. Results: We found that striatal group I metabotropic glutamate receptors are the principal mediator of the mGluR1/5 agonist (RS)-3,5-dihydroxyphenylglycine-induced cAMP responsive-element binding protein phosphorylation. Both acute and chronic cocaine self-administration blunted group I metabotropic glutamate receptor effects on cAMP responsive-element binding protein phosphorylation in the striatum, which correlated with the capacity to induce long-term depression, an effect that was maintained 60 days after chronic cocaine self-administration withdrawal. In the nucleus accumbens, the principal brain region mediating the rewarding effects of drugs, chronic cocaine self-administration blunted group I metabotropic glutamate receptor stimulation of extracellular signal-regulated protein kinases 1/2 and cAMP responsive-element binding protein. Interestingly, the group I metabotropic glutamate receptor antagonist/inverse-agonist, 2-methyl-6-(phenylethynyl)pyridine hydrochloride, led to a specific increase in cAMP responsive-element binding protein phosphorylation after chronic cocaine self-administration, specifically in the nucleus accumbens, but not in the striatum. Conclusions: Prolonged cocaine self-administration, through withdrawal, leads to a blunting of group I metabotropic glutamate receptor responses in the striatum. In addition, specifically in the accumbens, group I metabotropic glutamate receptor signaling to cAMP responsive-element binding protein shifts from an agonist-induced to an antagonist-induced cAMP responsive-element binding protein phosphorylation.
Cocaine-Related Disorders/metabolism , Cocaine/administration & dosage , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Dopamine Uptake Inhibitors/administration & dosage , Receptor, Metabotropic Glutamate 5/metabolism , Acute Disease , Animals , Chronic Disease , Cocaine-Related Disorders/pathology , Corpus Striatum/pathology , Disease Models, Animal , Excitatory Amino Acid Agents/pharmacology , MAP Kinase Signaling System/drug effects , MAP Kinase Signaling System/physiology , Male , Rats, Sprague-Dawley , Receptors, Metabotropic Glutamate/metabolism , Self Administration , Substance Withdrawal Syndrome/metabolism , Substance Withdrawal Syndrome/pathology , Tissue Culture Techniques
BACKGROUND: The atypical antipsychotic drug aripiprazole binds with high affinity to a number of G protein coupled receptors, including dopamine D2 receptors, where its degree of efficacy as a partial agonist remains controversial. METHODS: We examined the properties of aripiprazole at D2-like autoreceptors by monitoring the changes of dopamine synthesis in adult rat brain striatal minces incubated ex vivo. The effects of the dopaminergic tone on the properties of aripiprazole were assayed by comparing a basal condition (2 mM K(+), low dopaminergic tone) and a stimulated condition (15 mM K(+), where dopamine release mimics a relatively higher dopaminergic tone). We also used 2 reference compounds: quinpirole showed a clear agonistic activity and preclamol (S-(-)-PPP) showed partial agonism under both basal and stimulated conditions. RESULTS: Aripiprazole under the basal condition acted as an agonist at D2-like autoreceptors and fully activated them at about 10 nM, inhibiting dopamine synthesis similarly to quinpirole. Higher concentrations of aripiprazole had effects not restricted to D2-like autoreceptor activation. Under the stimulated (15 mM K(+)) condition, nanomolar concentrations of aripiprazole failed to decrease dopamine synthesis but could totally block the effect of quinpirole. CONCLUSIONS: Under high dopaminergic tone, aripiprazole acts as a D2-like autoreceptor antagonist rather than as an agonist. These data show that, ex vivo, alteration of dopaminergic tone by depolarization affects the actions of aripiprazole on D2-like autoreceptors. Such unusual effects were not seen with the typical partial agonist preclamol and are consistent with the hypothesis that aripiprazole is a functionally selective D2R ligand.
Aripiprazole/pharmacology , Autoreceptors/metabolism , Dopamine Agonists/pharmacology , Dopamine D2 Receptor Antagonists/pharmacology , Dopamine/biosynthesis , Receptors, Dopamine D2/metabolism , Animals , Autoreceptors/agonists , Autoreceptors/antagonists & inhibitors , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Dose-Response Relationship, Drug , Male , Piperidines/pharmacology , Potassium/metabolism , Presynaptic Terminals/drug effects , Presynaptic Terminals/metabolism , Quinpirole/pharmacology , Rats, Sprague-Dawley , Receptors, Dopamine D2/agonists
In vitro studies using excised human skin samples were conducted to evaluate the percutaneous absorption and skin metabolism of ozenoxacin. The formulations studied were 1% ointment, 1% cream and 2% cream. Permeation assays met the conditions for infinite dose experiments. In all but one case, ozenoxacin concentrations in receptor fluid samples of Franz diffusion cells were below the limits of quantification (0.04 µg/ml) by liquid chromatography/mass spectrometry/electrospray ionization at the designated time points. Across all four absorption studies, ≤ 0.015% of the applied ozenoxacin dose permeated through the skin over the course of 24 or 48 h. Ethnic origin had no influence on absorption. Ozenoxacin at concentrations of 7, 35 and 70 µM was metabolically stable in the presence of freshly prepared human skin discs.
Aminopyridines/pharmacokinetics , Anti-Bacterial Agents/pharmacokinetics , Quinolones/pharmacokinetics , Skin/metabolism , Drug Evaluation , Humans , In Vitro Techniques , Skin/drug effects , Skin Absorption
The general effects of cocaine are not well understood at the molecular level. What is known is that the dopamine D1 receptor plays an important role. Here we show that a key mechanism may be cocaine's blockade of the histamine H3 receptor-mediated inhibition of D1 receptor function. This blockade requires the σ1 receptor and occurs upon cocaine binding to σ1-D1-H3 receptor complexes. The cocaine-mediated disruption leaves an uninhibited D1 receptor that activates Gs, freely recruits ß-arrestin, increases p-ERK 1/2 levels, and induces cell death when over activated. Using in vitro assays with transfected cells and in ex vivo experiments using both rats acutely treated or self-administered with cocaine along with mice depleted of σ1 receptor, we show that blockade of σ1 receptor by an antagonist restores the protective H3 receptor-mediated brake on D1 receptor signaling and prevents the cell death from elevated D1 receptor signaling. These findings suggest that a combination therapy of σ1R antagonists with H3 receptor agonists could serve to reduce some effects of cocaine.
Cocaine/antagonists & inhibitors , Cocaine/metabolism , Receptors, Dopamine D1/metabolism , Receptors, Histamine H3/metabolism , Receptors, sigma/metabolism , Signal Transduction/drug effects , Animals , Benzamides/administration & dosage , Benzazepines/administration & dosage , Benzazepines/metabolism , Cell Line, Tumor , Cocaine/toxicity , Corpus Striatum/drug effects , Corpus Striatum/metabolism , Drug Delivery Systems/methods , HEK293 Cells , Humans , Male , Mice , Mice, Knockout , Organ Culture Techniques , Protein Binding/drug effects , Rats , Rats, Sprague-Dawley , Receptors, Dopamine D1/antagonists & inhibitors , Receptors, sigma/antagonists & inhibitors , Signal Transduction/physiology , Sigma-1 Receptor
BACKGROUND: The European Bioanalysis Forum dried blood spots (DBS)/microsampling consortium is reporting back from the experiments they performed on further documenting the potential hurdles of the DBS technology. This paper is focused on the impact of hematocrit changes on DBS analyses. RESULTS: The hematocrit can have an effect on the size of the blood spot, on spot homogeneity and on extraction recovery in a compound-dependent manner. The extraction recovery can change upon aging in an hematocrit-dependent way. Different card materials can give different outcomes. CONCLUSIONS: The results from the conducted experiments show that the issues of DBS in regulated bioanalysis are real and that the technology will need improvements to be ready for use as a general tool for regulated bioanalysis.
Dried Blood Spot Testing/standards , Hematocrit/standards , Specimen Handling/standards , Dried Blood Spot Testing/statistics & numerical data , Europe , Facility Regulation and Control , Humans , Independent Practice Associations , Reproducibility of Results , Solid Phase Microextraction , Solvents , Tandem Mass Spectrometry
BACKGROUND: At the start of their work, the European Bioanalysis Forum dried blood spots microsampling consortium did not form a dedicated team to investigate the spot homogeneity. However, two teams performed experiments that produced results relating to sample homogeneity. RESULTS: The data, which were produced via two different approaches (a radiolabeled and a nonradiolabeled approach), are highly complementary and demonstrate clear effects on sample inhomogeneity due to the substrate type, compound and hematocrit levels. CONCLUSION: The results demonstrate that sample inhomogeneity is a significant hurdle to the use of dried blood spots for regulated bioanalysis that should be investigated further in the method establishment phase if the whole spot is not sampled.
Dried Blood Spot Testing/standards , Hematocrit/standards , Specimen Handling/standards , Acetamides/blood , Animals , Carbon Radioisotopes , Deoxyglucose/blood , Dried Blood Spot Testing/statistics & numerical data , Europe , Facility Regulation and Control , Humans , Independent Practice Associations , Lacosamide , Mice , Rats , Reproducibility of Results , Tandem Mass Spectrometry
The role of the pineal gland is to translate the rhythmic cycles of night and day encoded by the retina into hormonal signals that are transmitted to the rest of the neuronal system in the form of serotonin and melatonin synthesis and release. Here we describe that the production of both melatonin and serotonin by the pineal gland is regulated by a circadian-related heteromerization of adrenergic and dopamine D4 receptors. Through α(1B)-D4 and ß1-D4 receptor heteromers dopamine inhibits adrenergic receptor signaling and blocks the synthesis of melatonin induced by adrenergic receptor ligands. This inhibition was not observed at hours of the day when D4 was not expressed. These data provide a new perspective on dopamine function and constitute the first example of a circadian-controlled receptor heteromer. The unanticipated heteromerization between adrenergic and dopamine D4 receptors provides a feedback mechanism for the neuronal hormone system in the form of dopamine to control circadian inputs.
Circadian Rhythm/physiology , Melatonin/biosynthesis , Pineal Gland/metabolism , Receptors, Adrenergic, alpha-1/metabolism , Receptors, Adrenergic, beta-1/metabolism , Receptors, Dopamine D4/metabolism , Animals , CHO Cells , Cricetinae , Dopamine/metabolism , HEK293 Cells , Humans , Male , Rats , Receptors, Adrenergic, alpha-1/genetics , Receptors, Adrenergic, beta-1/genetics , Receptors, Dopamine D4/genetics , Serotonin/biosynthesis , Transfection
