Kainate receptors regulate synaptic integrity and plasticity by forming a complex with synaptic organizers in the cerebellum.

Kainate (KA)-type glutamate receptors (KARs) are implicated in various neuropsychiatric and neurological disorders through their ionotropic and metabotropic actions. However, compared to AMPA- and NMDA-type receptor functions, many aspects of KAR biology remain incompletely understood. Our study demonstrates an important role of KARs in organizing climbing fiber (CF)-Purkinje cell (PC) synapses and synaptic plasticity in the cerebellum, independently of their ion channel or metabotropic functions. The amino-terminal domain (ATD) of the GluK4 KAR subunit binds to C1ql1, provided by CFs, and associates with Bai3, an adhesion-type G protein-coupled receptor expressed in PC dendrites. Mice lacking GluK4 exhibit no KAR-mediated responses, reduced C1ql1 and Bai3 levels, and fewer CF-PC synapses, along with impaired long-term depression and oculomotor learning. Remarkably, introduction of the ATD of GluK4 significantly improves all these phenotypes. These findings demonstrate that KARs act as synaptic scaffolds, orchestrating synapses by forming a KAR-C1ql1-Bai3 complex in the cerebellum.

Cost analysis of the enhanced recovery after surgery protocol applied in advanced ovarian cancer: A secondary outcome of the PROFAST trial.

INTRODUCTION: A randomised trial implementing Enhanced Recovery After Surgery (ERAS) for high complexity advanced ovarian cancer (AOC) surgery (PROFAST) demonstrated a reduction of median length of stay and hospital readmissions when compared to patients managed conventionally. One secondary objective was to determine if an ERAS pathway in the perioperative management of advanced ovarian cancer patients led to cost savings. MATERIAL AND METHODS: Secondary objective of a prospective randomised trial of patients with suspected or diagnosed advanced ovarian cancer allocated to conventional or ERAS perioperative management, carried out at a referral centre from June 2014 to March 2018. Treatment was determined by a computer-generated random allocation system. METHODS: Gross counting was employed to estimate the cost of hospitalisation in wards, intensive care unit (ICU) and surgical care, while micro-costing was used to obtain image and laboratory test costs. Mean costs between trial arms were considered. Sensitivity analyses were performed. RESULTS: Ninety-nine patients (n = 50 ERAS group, n = 49 Conventional group) were included. Mean costs per patient were 10,719€ in the ERAS group and 11,028€ in the conventional group, leading to an average saving of 309€ per patient. These results were based on 96 patients, excluding 3 extreme outliers mainly related with very high ICU costs. Savings, which were significant for hospital ward costs (-33% total; 759€ per patient in first hospitalisation, and 914€ per partient/day of readmission) were found as robust in the sensitivity analysis. CONCLUSIONS: Implementation of an ERAS pathway leads to cost savings when compared to conventional management after AOC surgery.

Transforming a public university hospital and its area of influence into a comprehensive resource in response to the COVID-19 pandemic.

INTRODUCTION AND OBJECTIVES: The outbreak of COVID-19 has overwhelmed healthcare systems all over the world. The aim of this article is to describe the process of transforming the Vall d'Hebron University Hospital, the second largest hospital in Spain, into a COVID-19 centre coordinating response to the pandemic in its reference area. MATERIALS AND METHODS: The study draws on the experience of the authors in transforming the hospital into a comprehensive resource in response to the COVID-19 pandemic. The strategy is based on four central strategies: early planning, coordination of all healthcare agents in its reference area, definition of clear leadership roles, and the organisation of care based on multidisciplinary teams with minimal recruitment of new staff. RESULTS: The transformation strategy enabled the hospital to cope with the surge in patients without exceeding its capacity. During the response phases, which amounted to a period of 57 days, 3106 patients consulted the ER and 2054 were admitted, 346 of whom were treated at the ICU. To accommodate the number of adult COVID-19 patients, adult ICU availability was progressive increased by 371%, and ordinary beds increased by 240. A total of 671 staff members went on sick leave after testing positive for COVID-19. CONCLUSION: The transformation experience of the hospital provides insight into how effectively adapt the structures and functioning of large hospitals. The relevance of territorial coordination during the pandemic is stressed as an effective strategy that contributed coping the pandemic.

Incidence, Clinical Characteristics, and Evolution of SARS-CoV-2 Infection in Patients With Inflammatory Bowel Disease: A Single-Center Study in Madrid, Spain.

BACKGROUND: There are scarce data about SARS-CoV-2 infection in patients with inflammatory bowel disease (IBD). Our aim was to analyze the incidence, clinical presentation, and severity of SARS-CoV-2 infection in patients with IBD. METHODS: This is a cross-sectional, observational study. We contacted all the patients being treated at our IBD unit to identify those patients with suspected or confirmed SARS-CoV-2 infection, following the World Health Organization case definition. Data were obtained by patient electronical medical records and by phone interview. RESULTS: Eighty-two of 805 patients with IBD (10.2%; 95% confidence interval [CI], 8.3-12.5) were diagnosed as having confirmed (28 patients, 3.5%; 95% CI, 2.4-5.0) or suspected (54 patients, 6.7%) infection. Patient age was 46 ± 14 years, 44 patients were female (53.7%), 17.3% were smokers, 51.2% had Crohn disease (CD), and 39.0% had comorbidities. Digestive symptoms were reported in 41 patients (50.0%), with diarrhea as the most common (42.7%). One patient (1.2%) was diagnosed with IBD flare-up during SARS-CoV-2 infection. Twenty-two patients (26.8%) temporarily withdrew from their IBD treatment because of COVID-19. Most of the patients had mild disease (79.3%), and 1 patient died (1.2%). In the multivariate analysis, the presence of dyspnea was associated with moderate to severe infection (odds ratio, 5.3; 95% CI, 1.6-17.7; P = 0.01) and myalgias (odds ratio, 4.8; 95% CI, 1.3-17.9; P = 0.02) were related to a milder clinical course. Immunosuppression was not related to severity. CONCLUSIONS: SARS-CoV-2 infection in patients with IBD is not rare. Dyspnea is associated with a more severe infection. Therapy for IBD, including immunomodulators and biologic therapy, is not related to a greater severity of COVID-19, and SARS-CoV-2 infections do not appear to be related to IBD flare-ups.

Mesenchymal Stem Cells for Liver Regeneration in Liver Failure: From Experimental Models to Clinical Trials.

The liver centralizes the systemic metabolism and thus controls and modulates the functions of the central and peripheral nervous systems, the immune system, and the endocrine system. In addition, the liver intervenes between the splanchnic and systemic venous circulation, determining an abdominal portal circulatory system. The liver displays a powerful regenerative potential that rebuilds the parenchyma after an injury. This regenerative mission is mainly carried out by resident liver cells. However, in many cases this regenerative capacity is insufficient and organ failure occurs. In normal livers, if the size of the liver is at least 30% of the original volume, hepatectomy can be performed safely. In cirrhotic livers, the threshold is 50% based on current practice and available data. Typically, portal vein embolization of the part of the liver that is going to be resected is employed to allow liver regeneration in two-stage liver resection after portal vein occlusion (PVO). However, hepatic resection often cannot be performed due to advanced disease progression or because it is not indicated in patients with cirrhosis. In such cases, liver transplantation is the only treatment possibility, and the need for transplantation is the common outcome of progressive liver disease. It is the only effective treatment and has high survival rates of 83% after the first year. However, donated organs are becoming less available, and mortality and the waiting lists have increased, leading to the initiation of living donor liver transplantations. This type of transplant has overall complications of 38%. In order to improve the treatment of hepatic injury, much research has been devoted to stem cells, in particular mesenchymal stem cells (MSCs), to promote liver regeneration. In this review, we will focus on the advances made using MSCs in animal models, human patients, ongoing clinical trials, and new strategies using 3D organoids.

The value of manure - Manure as co-product in life cycle assessment.

Livestock production is important for food security, nutrition, and landscape maintenance, but it is associated with several environmental impacts. To assess the risk and benefits arising from livestock production, transparent and robust indicators are required, such as those offered by life cycle assessment. A central question in such approaches is how environmental burden is allocated to livestock products and to manure that is re-used for agricultural production. To incentivize sustainable use of manure, it should be considered as a co-product as long as it is not disposed of, or wasted, or applied in excess of crop nutrient needs, in which case it should be treated as a waste. This paper proposes a theoretical approach to define nutrient requirements based on nutrient response curves to economic and physical optima and a pragmatic approach based on crop nutrient yield adjusted for nutrient losses to atmosphere and water. Allocation of environmental burden to manure and other livestock products is then based on the nutrient value from manure for crop production using the price of fertilizer nutrients. We illustrate and discuss the proposed method with two case studies.

Población y metodología del estudio SIMETAP: Prevalencia de factores de riesgo cardiovascular, enfermedades cardiovasculares y enfermedades metabólicas relacionadas / Population and methodology of the SIMETAP study: Prevalence of cardiovascular risk factors, cardiovascular diseases, and related metabolic diseases

La prevención de la enfermedad cardiovascular se fundamenta en la detección y control de los factores de riesgo cardiovascular (FRCV). En España existen importantes diferencias territoriales tanto en la prevalencia como en el grado de control de los FRCV. En la última década ha habido una mejora del control de la hipertensión y la dislipidemia, pero un empeoramiento de los factores de riesgo cardiometabólicos relacionados con la obesidad y la diabetes. El estudio SIMETAP es un estudio observacional descriptivo transversal realizado en 64 centros de atención primaria de la Comunidad de Madrid. El objetivo principal es determinar las tasas de prevalencia de FRCV, de las enfermedades cardiovasculares y de las enfermedades metabólicas relacionadas con el riesgo cardiovascular. El presente artículo informa sobre las características basales de la población, la metodología del estudio, y las definiciones de los parámetros y enfermedades en estudio. Se seleccionaron 6.631 sujetos de estudio mediante una muestra aleatoria base poblacional. Se determinaron variables antropométricas, estilos de vida, presión arterial, parámetros bioquímicos, y tratamientos farmacológicos. Las prevalencias crudas más elevadas se detectaron en tabaquismo, inactividad física, obesidad, prediabetes, diabetes, hipertensión, dislipidemias y síndrome metabólico. Para valorar la verdadera dimensión epidemiológica de estas enfermedades y FRCV, es necesario realizar un análisis pormenorizado de tasas de prevalencia estratificadas por grupos etarios y de las tasas de prevalencia ajustadas por edad y sexo

The prevention of cardiovascular disease is based on the detection and control of cardiovascular risk factors (CVRF). In Spain there are important geographical differences both in the prevalence and in the level of control of the CVRF. In the last decade there has been an improvement in the control of hypertension and dyslipidaemia, but a worsening of cardio-metabolic risk factors related to obesity and diabetes. The SIMETAP study is a cross-sectional descriptive, observational study being conducted in 64 Primary Care Centres located at the Community of Madrid. The main objective is to determine the prevalence rates of CVRF, cardiovascular diseases, and metabolic diseases related to cardiovascular risk. A report is presented on the baseline characteristics of the population, the study methodology, and the definitions of the parameters and diseases under study. A total of 6,631 study subjects were selected using a population-based random sample. The anthropometric variables, lifestyles, blood pressure, biochemical parameters, and pharmacological treatments were determined. The highest crude prevalences were detected in smoking, physical inactivity, obesity, prediabetes, diabetes, hypertension, dyslipidaemias, and metabolic syndrome. A detailed analysis needs to be performed on the prevalence rates, stratified by age groups, and prevalence rates adjusted for age and sex to assess the true epidemiological dimension of these CVRF and diseases

Population and methodology of the SIMETAP study: Prevalence of cardiovascular risk factors, cardiovascular diseases, and related metabolic diseases. / Población y metodología del estudio SIMETAP: Prevalencia de factores de riesgo cardiovascular, enfermedades cardiovasculares y enfermedades metabólicas relacionadas.

The prevention of cardiovascular disease is based on the detection and control of cardiovascular risk factors (CVRF). In Spain there are important geographical differences both in the prevalence and in the level of control of the CVRF. In the last decade there has been an improvement in the control of hypertension and dyslipidaemia, but a worsening of cardio-metabolic risk factors related to obesity and diabetes. The SIMETAP study is a cross-sectional descriptive, observational study being conducted in 64 Primary Care Centres located at the Community of Madrid. The main objective is to determine the prevalence rates of CVRF, cardiovascular diseases, and metabolic diseases related to cardiovascular risk. A report is presented on the baseline characteristics of the population, the study methodology, and the definitions of the parameters and diseases under study. A total of 6,631 study subjects were selected using a population-based random sample. The anthropometric variables, lifestyles, blood pressure, biochemical parameters, and pharmacological treatments were determined. The highest crude prevalences were detected in smoking, physical inactivity, obesity, prediabetes, diabetes, hypertension, dyslipidaemias, and metabolic syndrome. A detailed analysis needs to be performed on the prevalence rates, stratified by age groups, and prevalence rates adjusted for age and sex to assess the true epidemiological dimension of these CVRF and diseases.

Increased Grik4 Gene Dosage Causes Imbalanced Circuit Output and Human Disease-Related Behaviors.

Altered glutamatergic neurotransmission is thought to contribute to mental disorders and neurodegenerative diseases. Copy-number variation in genes associated with glutamatergic synapses represents a source of genetic variability, possibly underlying neurological and mental disease susceptibility. The GRIK4 gene encodes a high-affinity kainate receptor subunit of essentially unknown function, although de novo duplication of the 11q23.3-q24.1 locus to which it maps has been detected in autism and other disorders. To determine how changes in the dose of Grik4 affect synaptic activity, we studied mice overexpressing this gene in the forebrain. A mild gain in Grik4 enhances synaptic transmission, causing a persistent imbalance in inhibitory and excitatory activity and disturbing the circuits responsible for the main amygdala outputs. These changes in glutamatergic activity reverse when Grik4 levels are normalized; thus, they may account for the behavioral abnormalities in disorders like autism or schizophrenia.

Patient perceptions of continuity of health care and associated factors. Cross-sectional study in municipalities of central Colombia and north-eastern Brazil.

Despite the fragmentation of healthcare provision being considered one of the main obstacles to attaining effective health care in Latin America, very little is known about patients' perceptions. This paper analyses the level of continuity of health care perceived by users and explores influencing factors in two municipalities of Colombia and Brazil, by means of a cross-sectional study based on a survey of a multistage probability sample of people who had suffered at least one health problem within the previous three months (2163 in Colombia; 2167 in Brazil). An adapted and validated version of the CCAENA© (Questionnaire of care continuity across levels of health care) was applied. Logistic regression models were generated to assess the relationship between perceptions of the different types of health care continuity and sociodemographic characteristics, health needs, and organizational factors. The results show lower levels of continuity across care levels in information transfer and care coherence and higher levels for the ongoing patient-doctor relationship, albeit with differences between the two countries. They also show greater consistency of doctors in the Brazilian study areas, especially in primary care. Consistency of doctors was not only positively associated with the patient-doctor ongoing relationship in the study areas of both countries, but also with information transfer and care coherence across care levels. The study area and health needs (the latter negatively for patients with poor self-rated health and positively for those with at least one chronic condition) were associated with all types of continuity of care. The influence of the sex or income varied depending on the country. The influence of the insurance scheme in the Colombian sample was not statistically significant. Both countries should implement policies to improve coordination between care levels, especially regarding information transfer and job stability for primary care doctors, both key factors to guarantee quality of care.

The Complex Interplay Between Multisensory Integration and Perceptual Awareness.

The integration of information has been considered a hallmark of human consciousness, as it requires information being globally available via widespread neural interactions. Yet the complex interdependencies between multisensory integration and perceptual awareness, or consciousness, remain to be defined. While perceptual awareness has traditionally been studied in a single sense, in recent years we have witnessed a surge of interest in the role of multisensory integration in perceptual awareness. Based on a recent IMRF symposium on multisensory awareness, this review discusses three key questions from conceptual, methodological and experimental perspectives: (1) What do we study when we study multisensory awareness? (2) What is the relationship between multisensory integration and perceptual awareness? (3) Which experimental approaches are most promising to characterize multisensory awareness? We hope that this review paper will provoke lively discussions, novel experiments, and conceptual considerations to advance our understanding of the multifaceted interplay between multisensory integration and consciousness.

Decompensated liver cirrhosis and neural regulation of mesenteric vascular tone in rats: role of sympathetic, nitrergic and sensory innervations.

We evaluated the possible alterations produced by liver cholestasis (LC), a model of decompensated liver cirrhosis in sympathetic, sensory and nitrergic nerve function in rat superior mesenteric arteries (SMA). The vasoconstrictor response to electrical field stimulation (EFS) was greater in LC animals. Alpha-adrenoceptor antagonist phentolamine and P2 purinoceptor antagonist suramin decreased this response in LC animals more than in control animals. Both non-specific nitric oxide synthase (NOS) L-NAME and calcitonin gene related peptide (CGRP) (8-37) increased the vasoconstrictor response to EFS more strongly in LC than in control segments. Vasomotor responses to noradrenaline (NA) or CGRP were greater in LC segments, while NO analogue DEA-NO induced a similar vasodilation in both experimental groups. The release of NA was not modified, while those of ATP, nitrite and CGRP were increased in segments from LC. Alpha 1 adrenoceptor, Rho kinase (ROCK) 1 and 2 and total myosin phosphatase (MYPT) expressions were not modified, while alpha 2B adrenoceptor, nNOS expression and nNOS and MYPT phosphorylation were increased by LC. Together, these alterations might counteract the increased splanchnic vasodilation observed in the last phases of decompensated liver cirrhosis.

ATP-Evoked Intracellular Ca²âº Signaling of Different Supporting Cells in the Hearing Mouse Hemicochlea.

Hearing and its protection is regulated by ATP-evoked Ca(2+) signaling in the supporting cells of the organ of Corti, however, the unique anatomy of the cochlea hampers observing these mechanisms. For the first time, we have performed functional ratiometric Ca(2+) imaging (fura-2) in three different supporting cell types in the hemicochlea preparation of hearing mice to measure purinergic receptor-mediated Ca(2+) signaling in pillar, Deiters' and Hensen's cells. Their resting [Ca(2+)]i was determined and compared in the same type of preparation. ATP evoked reversible, repeatable and dose-dependent Ca(2+) transients in all three cell types, showing desensitization. Inhibiting the Ca(2+) signaling of the ionotropic P2X (omission of extracellular Ca(2+)) and metabotropic P2Y purinergic receptors (depletion of intracellular Ca(2+) stores) revealed the involvement of both receptor types. Detection of P2X2,3,4,6,7 and P2Y1,2,6,12,14 receptor mRNAs by RT-PCR supported this finding and antagonism by PPADS suggested different functional purinergic receptor population in pillar versus Deiters' and Hensen's cells. The sum of the extra- and intracellular Ca(2+)-dependent components of the response was about equal with the control ATP response (linear additivity) in pillar cells, and showed supralinearity in Deiters' and Hensen's cells. Calcium-induced calcium release might explain this synergistic interaction. The more pronounced Ca(2+) leak from the endoplasmic reticulum in Deiters' and Hensen's cells, unmasked by cyclopiazonic acid, may also suggests the higher activity of the internal stores in Ca(2+) signaling in these cells. Differences in Ca(2+) homeostasis and ATP-induced Ca(2+) signaling might reflect the distinct roles these cells play in cochlear function and pathophysiology.

Synaptic Targeting of Kainate Receptors.

When native and recombinant kainate receptors (KARs) are compared, there is a mismatch in several of their functional properties. While both generate currents, synaptic responses mediated by KARs have rarely observed in cultured hippocampal neurons. The recent discovery of auxiliary proteins for KARs, such as Netos, offers an explanation for these discrepancies. We found that the GluK5 KAR subunit and the ancillary proteins, Neto1 and Neto2, are not expressed by hippocampal neurons in culture. Therefore, we used this model to directly test whether these proteins are required for the synaptic localization of KARs. Transfection of GluK4, GluK5, Neto1, or Neto2 into hippocampal neurons was associated with the appearance of synaptic KAR-mediated EPSCs. However, GluK4 or GluK5 alone produced synaptic activity in a significant proportion of cells and with reliable event frequency. While neurons expressing GluK4 or GluK5 subunits displayed synaptic responses with rapid kinetics, the expression of Neto proteins conferred these synaptic responses with their characteristic slow onset and decay rates. These data reveal some requirements for KAR targeting to the synapse, indicating a fundamental role of high affinity KAR subunits in this process.

Continuous wave terahertz radiation from antennas fabricated on C¹²-irradiated semi-insulating GaAs.

We demonstrate continuous wave (CW) terahertz generation from antennas fabricated on C12-irradiated semi-insulating (SI) GaAs substrates. The dark current drawn by the antennas fabricated on irradiated substrates is ∼3 to 4 orders of magnitude lower compared to antennas fabricated on un-irradiated substrates, while the photocurrents decrease by only ∼1.5 orders of magnitude. This can be attributed to the strong reduction of the carrier lifetime that is 2.5 orders of magnitude, with values around τ(rec)=0.2 ps. Reduced thermal heating allows for higher bias voltages to the irradiated antenna devices resulting in higher CW terahertz power, just slightly lower than that of low-temperature grown GaAs (LT GaAs)at similar excitation conditions.

Increased Dosage of High-Affinity Kainate Receptor Gene grik4 Alters Synaptic Transmission and Reproduces Autism Spectrum Disorders Features.

The understanding of brain diseases requires the identification of the molecular, synaptic, and cellular disruptions underpinning the behavioral features that define the disease. The importance of genes related to synaptic function in brain disease has been implied in studies describing de novo germline mutations and copy number variants. Indeed, de novo copy number variations (deletion or duplication of a chromosomal region) of synaptic genes have been recently implicated as risk factors for mental retardation or autism. Among these genes is GRIK4, a gene coding for a glutamate receptor subunit of the kainate type. Here we show that mice overexpressing grik4 in the forebrain displayed social impairment, enhanced anxiety, and depressive states, accompanied by altered synaptic transmission, showing more efficient information transfer through the hippocampal trisynaptic circuit. Together, these data indicate that a single gene variation in the glutamatergic system results in behavioral symptomatology consistent with autism spectrum disorders as well as in alterations in synaptic function in regions involved in social activity. Autistic features of these mice represent powerful tools for improving diagnosis and testing of specific treatments targeting abnormalities in glutamatergic signaling related to autism spectrum disorders. SIGNIFICANCE STATEMENT: A genetic overlap exists between autism spectrum disorders (ASD), currently thought to represent a continuum of the same disorder with varying degrees of severity, and other neurodevelopmental and neuropsychiatric endophenotypes. We show that the duplication of a single gene coding for a high-affinity kainate receptor subunit (i.e., grik4) in a limited area of the brain recapitulates behavioral endophenotypes seen in humans diagnosed with autism (anhedonia, depression, anxiety, and altered social interaction), including some humans with GRIK4 duplications. Therefore, it should be possible to use mice overexpressing grik4 to directly address circuit dysfunctions associated with ASDs and test specific treatments of autism-related behaviors.

A proteomic analysis reveals the interaction of GluK1 ionotropic kainate receptor subunits with Go proteins.

Kainate receptors (KARs) are found ubiquitously in the CNS and are present presynaptically and postsynaptically regulating synaptic transmission and excitability. Functional studies have proven that KARs act as ion channels as well as potentially activating G-proteins, thus indicating the existance of a dual signaling system for KARs. Nevertheless, it is not clear how these ion channels activate G-proteins and which of the KAR subunits is involved. Here we performed a proteomic analysis to define proteins that interact with the C-terminal domain of GluK1 and we identified a variety of proteins with many different functions, including a Go α subunit. These interactions were verified through distinct in vitro and in vivo assays, and the activation of the Go protein by GluK1 was validated in bioluminescence resonance energy transfer experiments, while the specificity of this association was confirmed in GluK1-deficient mice. These data reveal components of the KAR interactome, and they show that GluK1 and Go proteins are natural partners, accounting for the metabotropic effects of KARs.

Protective effect of rasagiline in aminoglycoside ototoxicity.

Sensorineural hearing losses (SNHLs; e.g., ototoxicant- and noise-induced hearing loss or presbycusis) are among the most frequent sensory deficits, but they lack effective drug therapies. The majority of recent therapeutic approaches focused on the trials of antioxidants and reactive oxygen species (ROS) scavengers in SNHLs. The rationale for these studies was the prominent role of disturbed redox homeostasis and the consequent ROS elevation. Although the antioxidant therapies in several animal studies seemed to be promising, clinical trials have failed to fulfill expectations. We investigated the potential of rasagiline, an FDA-approved monomanine oxidase type B inhibitor (MAO-B) inhibitor type anti-parkinsonian drug, as an otoprotectant. We showed a dose-dependent alleviation of the kanamycin-induced threshold shifts measured by auditory brainstem response (ABR) in an ototoxicant aminoglycoside antibiotic-based hearing loss model in mice. This effect proved to be statistically significant at a 6-mg/kg (s.c.) dose. The most prominent effect appeared at 16kHz, which is the hearing sensitivity optimum for mice. The neuroprotective, antiapoptotic and antioxidant effects of rasagiline in animal models, all targeting a specific mechanism of aminoglycoside injury, may explain this otoprotection. The dopaminergic neurotransmission enhancer effect of rasagiline might also contribute to the protection. Dopamine (DA), released from lateral olivocochlear (LOC) fibers, was shown to exert a protective action against excitotoxicity, a pathological factor in the aminoglycoside-induced SNHL. We have shown that rasagiline enhanced the electric stimulation-evoked release of DA from an acute mouse cochlea preparation in a dose-dependent manner. Using inhibitors of voltage-gated Na(+)-, Ca(2+) channels and DA transporters, we revealed that rasagiline potentiated the action potential-evoked release of DA by inhibiting the reuptake. The complex, multifactorial pathomechanism of SNHLs most likely requires drugs acting on multiple targets for effective therapy. Rasagiline, with its multi-target action and favorable adverse effects profile, might be a good candidate for a clinical trial testing the otoprotective indication.

Immunosuppressive properties of mesenchymal stem cells: advances and applications.

Mesenchymal stem cells (MSCs) have been isolated from a variety of tissues, such as bone marrow, skeletal muscle, dental pulp, bone, umbilical cord and adipose tissue. MSCs are used in regenerative medicine mainly based on their capacity to differentiate into specific cell types and also as bioreactors of soluble factors that will promote tissue regeneration from the damaged tissue cellular progenitors. In addition to these regenerative properties, MSCs hold an immunoregulatory capacity, and elicit immunosuppressive effects in a number of situations. Not only are they immunoprivileged cells, due to the low expression of class II Major Histocompatibilty Complex (MHC-II) and costimulatory molecules in their cell surface, but they also interfere with different pathways of the immune response by means of direct cell-to-cell interactions and soluble factor secretion. In vitro, MSCs inhibit cell proliferation of T cells, B-cells, natural killer cells (NK) and dendritic cells (DC), producing what is known as division arrest anergy. Moreover, MSCs can stop a variety of immune cell functions: cytokine secretion and cytotoxicity of T and NK cells; B cell maturation and antibody secretion; DC maturation and activation; as well as antigen presentation. It is thought that MSCs need to be activated to exert their immunomodulation skills. In this scenario, an inflammatory environment seems to be necessary to promote their effect and some inflammation-related molecules such as tumor necrosis factor-α and interferon-γ might be implicated. It has been observed that MSCs recruit T-regulatory lymphocytes (Tregs) to both lymphoid organs and graft. There is great controversy concerning the mechanisms and molecules involved in the immunosuppressive effect of MSCs. Prostaglandin E2, transforming growth factor-ß, interleukins- 6 and 10, human leukocyte antigen-G5, matrix metalloproteinases, indoleamine-2,3-dioxygenase and nitric oxide are all candidates under investigation. In vivo studies have shown many discrepancies regarding the immunomodulatory properties of MSCs. These studies have been designed to test the efficacy of MSC therapy in two different immune settings: the prevention or treatment of allograft rejection episodes, and the ability to suppress abnormal immune response in autoimmune and inflammatory diseases. Preclinical studies have been conducted in rodents, rabbits and baboon monkeys among others for bone marrow, skin, heart, and corneal transplantation, graft versus host disease, hepatic and renal failure, lung injury, multiple sclerosis, rheumatoid arthritis, diabetes and lupus diseases. Preliminary results from some of these studies have led to human clinical trials that are currently being carried out. These include treatment of autoimmune diseases such as Crohn's disease, ulcerative colitis, multiple sclerosis and type 1 diabetes mellitus; prevention of allograft rejection and enhancement of the survival of bone marrow and kidney grafts; and treatment of resistant graft versus host disease. We will try to shed light on all these studies, and analyze why the results are so contradictory.