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Humans and their microbiota have coevolved a mutually beneficial relationship in which the human host provides a hospitable environment for the microorganisms and the microbiota provides many advantages for the host, including nutritional benefits and protection from pathogen infection1. Maintaining this relationship requires a careful immune balance to contain commensal microorganisms within the lumen while limiting inflammatory anti-commensal responses1,2. Antigen-specific recognition of intestinal microorganisms by T cells has previously been described3,4. Although the local environment shapes the differentiation of effector cells3-5 it is unclear how microbiota-specific T cells are educated in the thymus. Here we show that intestinal colonization in early life leads to the trafficking of microbial antigens from the intestine to the thymus by intestinal dendritic cells, which then induce the expansion of microbiota-specific T cells. Once in the periphery, microbiota-specific T cells have pathogenic potential or can protect against related pathogens. In this way, the developing microbiota shapes and expands the thymic and peripheral T cell repertoire, allowing for enhanced recognition of intestinal microorganisms and pathogens.
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Células Dendríticas/inmunología , Microbioma Gastrointestinal/inmunología , Linfocitos T/citología , Linfocitos T/inmunología , Timo/citología , Timo/inmunología , Envejecimiento/inmunología , Animales , Antígenos Bacterianos/inmunología , Antígenos Bacterianos/metabolismo , Receptor 1 de Quimiocinas CX3C/metabolismo , ADN Bacteriano/análisis , Células Dendríticas/metabolismo , Escherichia coli/inmunología , Femenino , Masculino , Ratones , Especificidad de Órganos , Salmonella/inmunología , Simbiosis/inmunología , Timo/metabolismoRESUMEN
The historic center of Quito, Ecuador, was one of the first World Cultural Heritage Sites declared by UNESCO in 1978. There are numerous religious buildings built during the Spanish colonial period reflecting the cultural heritage in this area. Between them, the cloisters of San Francisco, Santo Domingo, and Santa Clara should be highlighted. The specific problems of conservation of the outdoor canvas paintings are not well known at the moment. The objective of this paper is to achieve a conservation study of the canvas paintings exhibited in these three cloisters of the historic center of Quito in order to identify the microbial agents and the main bioclimatic parameters of deterioration. For this, a study of the state of conservation of five canvas paintings has been carried out, as well as a sampling and identification of the main microorganisms present on the obverse and reverse of the works, employing diverse techniques, traditional and biomolecular ones. An analysis of climatic conditions has also been achieved in the cloister of San Francisco. The results of the study indicate that the exhibition conditions in the cloisters are really problematic for the conservation of paintings. Important biodeteriorating agents have been isolated, including fungi and bacteria species belonging, among others, to the genera Bacillus, Penicillium, Alternaria, Mucor, and Aspergillus. We have also researched its relationship with the deterioration state of the artworks and the exhibition conditions in each case, proposing guidelines for the proper conservation of this important World Cultural Heritage.
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Bacterias/aislamiento & purificación , Hongos/aislamiento & purificación , Pinturas , Textiles/microbiología , Alternaria/genética , Alternaria/aislamiento & purificación , Aspergillus/genética , Aspergillus/aislamiento & purificación , Bacillus/genética , Bacillus/aislamiento & purificación , Bacterias/clasificación , Bacterias/genética , Candida/genética , Candida/aislamiento & purificación , ADN Bacteriano/genética , ADN Bacteriano/aislamiento & purificación , ADN de Hongos/genética , ADN de Hongos/aislamiento & purificación , Ecuador , Microbiología Ambiental , Hongos/clasificación , Hongos/genética , Humanos , Penicillium/genética , Penicillium/aislamiento & purificación , Reacción en Cadena de la Polimerasa/métodos , Staphylococcus/genética , Staphylococcus/aislamiento & purificaciónRESUMEN
The study of the physiological action of microorganisms in artistic materials is one of the most interesting topics in biodeterioration nowadays. Pathologies and illnesses of organic and inorganic materials provoked by microorganisms can be treated by experts by a variety of preventive interventions. Artistic medicine encompasses the monitoring of the exhibition and storage of art, as well as proper environmental conditions and the regular cleaning of museums. Biodeterioration control is essential in order to prevent fungal and bacterial contamination in artwork. Biodeterioration of canvas paintings is a complex phenomenon, not well-known at the moment. Canvas paintings are created by several artistic techniques on textile supports that are not always kept in the best conditions, and the best parameters of preventive conservation are often not applied. Therefore, we need to research the agents and the main causes that provoke canvas painting biodeterioration. By applying new methodologies, we can identify the alterations and the treatments needed in order to manage the diverse materials employed in artwork correctly. Herein, we review the causes of biodeterioration that affect artwork, especially art created on textile supports. We also study the alterations of the natural filmogenic materials employed in traditional pictorial techniques, such as agglutinants and protection layers, and the biodeterioration agents that impact them. Additionally, we review current scientific methods employed for the identification of microbial species, and the types of alterations of the materials where the organisms grow. Finally, we summarize the different biocides and preventive conservation treatments that are currently employed.
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Arte , Bacterias/metabolismo , Hongos/metabolismo , Pinturas , Bacterias/efectos de los fármacos , Desinfectantes/farmacología , Ambiente , Hongos/efectos de los fármacos , Hongos/ultraestructuraRESUMEN
Cyclin-Dependent Kinase 9 (CDK9) is part of a functional diverse group of enzymes responsible for cell cycle control and progression. It associates mainly with Cyclin T1 and forms the Positive Transcription Elongation Factor b (p-TEFb) complex responsible for regulation of transcription elongation and mRNA maturation. Recent studies have highlighted the importance of CDK9 in many relevant pathologic processes, like cancer, cardiovascular diseases, and viral replication. Herein we provide an overview of the different pathways in which CDK9 is directly and indirectly involved.
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Enfermedades Cardiovasculares/metabolismo , Quinasa 9 Dependiente de la Ciclina/metabolismo , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Virosis/metabolismo , Animales , Enfermedades Cardiovasculares/genética , Ciclina T/genética , Ciclina T/metabolismo , Quinasa 9 Dependiente de la Ciclina/genética , Humanos , Proteínas de Neoplasias/genética , Neoplasias/genética , Factor B de Elongación Transcripcional Positiva/genética , Factor B de Elongación Transcripcional Positiva/metabolismo , Elongación de la Transcripción Genética , Virosis/genéticaRESUMEN
Undoubtedly, the focus of the field of stem cell research is predominantly aimed at the artificial reprogramming of human somatic cells for the production of induced pluripotent stem (iPS) cells. This relatively new technology may circumvent the ethical issues of using human embryonic stem (hES) cells for the potential applications in cell replacement therapy. Besides such ethical issues, iPS cell technology offers the advantage of obtaining patient-derived tissues and/or cells, which may be utilized for autologous transplantation and tissue regeneration, investigation of a variety of human illnesses and for the screening of new drugs. The field of stem cell research has placed a major emphasis in understanding the genetic and epigenetic codes for pluripotency, in order to control and optimize autologous transplantation techniques and avoid teratoma formation.
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Células Madre Pluripotentes Inducidas/fisiología , Células Madre Pluripotentes Inducidas/trasplante , Evaluación Preclínica de Medicamentos/métodos , Humanos , Trasplante AutólogoRESUMEN
Aquatic macroinvertebrates are the group of organisms most commonly used to determine ecosystem health in water quality studies and freshwater biomonitoring. Nevertheless, the methods and collecting time of biomonitoring have not yet been sufficiently adapted and tested in tropical aquatic environments. Twelve rivers in the Lago de Atitlán watershed in Guatemala were assessed with different collecting times, during the dry season. The method involved the collection of organic and inorganic material including benthic organisms, from different microhabitats, for a pre-established time period (5, 10, 15 min) with a D-frame net. Samples were preserved with 95% ethanol in the field, and sorted in the laboratory. As expected, the analysis showed that the abundance and taxonomic richness was higher with increasing sampling effort. The water quality categories obtained from the newly proposed BMWP/Atitlán index varied among sampling times. However, the Kruskal-Wallis test showed no significant differences between the categories obtained with the index and the number of taxa collected at 10 and 15 min. Therefore, we recommend a reduction of sample time, but maintaining the tree subsamples in order to include most variety of microhabitats and assure a representative sample of the aquatic macroinvertebrates.
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Biodiversidad , Monitoreo del Ambiente/métodos , Invertebrados/clasificación , Ríos , Calidad del Agua , Animales , Guatemala , Estaciones del AñoRESUMEN
BACKGROUND: The number of people living in a different place from their place of birth is increasing year by year. Although women have always been involved in migratory movements, today they are increasingly doing so independently. Women are migrating from the Global South to higher-income countries. One of the challenges they face is access to sexual and reproductive health (SRH) services. AIM: To identify the policy-level barriers that limit the access of migrant women to SRH services, their consequences, and strategies implemented to overcome these barriers. METHODS: A systematic review of the literature was undertaken in accordance with the PRISMA statement. A search was undertaken for articles published between 2018 and 2023 focusing on migrant women's experiences of SRH services. In total, 462 articles were retrieved from PubMed (n = 135), Scopus (n = 94) and Web of Science (n = 233); of these, 28 articles were included in this review. FINDINGS: The most common barrier to SRH services identified in the reviewed articles was lack of information (57 %), followed by language issues (43 %), cultural differences (39 %), economic status (25 %), administrative barriers (25 %) and discrimination (14 %). These barriers led to under-utilisation of maternity services and contraceptive methods. Strategies used by migrant women to overcome these barriers were primarily based on seeking help within their own community or family settings. CONCLUSION: Strategies at institutional level to improve the access of migrant women to SRH services need to reduce existing barriers, promote health literacy, and train health workers to be culturally sensitive and responsive to the needs of migrant women.
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(1) Background: Aspergillus spp. is a widely distributed filamentous fungus in the environment due to its high sporulation capacity. Currently, invasive aspergillosis (IA) is the most common invasive fungal infection in patients with hematologic malignancies, with high rates of mortality and morbidity. The multifactorial nature of the disease requires appropriate risk stratification to enable the most appropriate preventive measures to be adapted and implemented according to the characteristics of the patient. In this sense, the present research aims to identify recent risk factors and environmental control measures against invasive aspergillosis to establish preventive actions to reduce the incidence of invasive aspergillosis in hospitals. (2) Methods: We conducted a qualitative systematic review of the scientific literature on environmental risk factors and preventive measures for invasive aspergillosis in patients with hematologic malignancies. The Medline, Cochrane, and Scopus databases were consulted, following the PRISMA and STROBE guidelines. (3) Results: Adequate implementation of environmental control measures is presented as the most efficient intervention in terms of prevention to decrease the incidence of invasive aspergillosis in hospitals. Neutropenia, fungal contamination, insufficient environmental control measures in hospital and home settings, length of hospital stay, and anemia, are identified as independent risk factors. We show that HEPA, LAF, and Plasmair® systems are suitable methods to reduce the concentration of airborne fungal spores. Antifungal prophylaxis did not significantly influence IA reduction in our study. (4) Conclusions: Proper professional training and environmental control measures in hospitals are essential for the prevention of invasive aspergillosis. We should optimize risk stratification for patients with hematologic malignancies. Antifungal prophylaxis should be complementary to environmental control measures and should never be substituted for the latter. Studies should also be undertaken to evaluate the efficiency of environmental control measures against IA at patients' homes.
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BACKGROUND: Diabetic peripheral neuropathy (DPN) is the most common complication of type 2 diabetes mellitus (T2DM); its diagnosis and treatment are based on symptomatic improvement. However, as pharmacological therapy causes multiple adverse effects, the implementation of acupunctural techniques, such as electroacupuncture (EA) has been suggested as an alternative treatment. Nonetheless, there is a lack of scientific evidence, and its mechanisms are still unclear. We present the design and methodology of a new clinical randomized trial, that investigates the effectiveness of EA for the treatment of DPN. METHODS: This study is a four-armed, randomized, controlled, multicenter clinical trial (20-week intervention period, plus 12 weeks of follow-up after concluding intervention). A total of 48 T2DM patients with clinical signs and symptoms of DPN; and electrophysiological signs in the Nerve Conduction Study (NCS); will be treated by acupuncture specialists in outpatient units in Mexico City. Patients will be randomized in a 1:1 ratio to one of the following four groups: (a) short fibre DPN with EA, (b) short fibre DPN with sham EA, (c) axonal DPN with EA and (d) axonal DPN with sham EA treatment. The intervention will consist of 32 sessions, 20 min each, per patient over two cycles of intervention of 8 weeks each and a mid-term rest period of 4 weeks. The primary outcome will be NCS parameters, and secondary outcomes will include DPN-related symptoms and pain by Michigan Neuropathy Screening Instrument (MNSI), Michigan Diabetic Neuropathy Score (MDNS), Dolour Neuropatique Score (DN-4), Semmes-Westein monofilament, Numerical Rating Scale (NRS) for pain assessment, and the 36-item Short Form Health Survey (SF-36). To measure quality of life and improve oxidative stress, the inflammatory response; and genetic expression; will be analysed at the beginning and at the end of treatment. DISCUSSION: This study will be conducted to compare the efficacy of EA versus sham EA combined with conventional diabetic and neuropathic treatments if needed. EA may improve NCS, neuropathic pain and symptoms, oxidative stress, inflammatory response, and genetic expression, and it could be considered a potential coadjutant treatment for the management of DPN with a possible remyelinating effect. TRIAL REGISTRATION: ClinicalTrials.gov. NCT05521737 Registered on 30 August 2022. International Clinical Trials Registry Platform (ICTRP) ISRCTN97391213 Registered on 26 September 2022 [2b].
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Terapia por Acupuntura , Diabetes Mellitus Tipo 2 , Neuropatías Diabéticas , Electroacupuntura , Humanos , Neuropatías Diabéticas/terapia , Electroacupuntura/métodos , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/terapia , Calidad de Vida , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como AsuntoRESUMEN
Breast cancer screening through periodic mammography has been effective in decreasing mortality and reducing the impact of this disease. However, adherence to screening does not meet the desired expectations from all populations. The main objective of this review is to explore the barriers that affect adherence to breast cancer-screening programs in vulnerable populations according to race and/or ethnicity in order to propose measures to reduce the lack of adherence. We conducted a search of publications in the PubMed Central and Scopus databases. The eligible criteria for the articles were as follows: original quantitative studies appearing in SJR- and/or JCR-indexed journals from 2016 to 2021 in English or Spanish. Most of them present common barriers, such as race/ethnicity (47%), low socioeconomic (35.3%) and educational levels (29.4%), no family history of cancer and being single (29.4%), medical mistrust and a health information gap (23.5%), lack of private health insurance (17.6%) and not having annual health checks (17.6%). The target populations with the lowest adherence were Black, Asian, Hispanic and foreign women. Implementing awareness campaigns focused on these populations should be promoted, as well as working on diversity, cultural acceptance and respect with healthcare workers, in order to improve breast cancer-screening adherence worldwide.
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Malnutrition refers to a person's status as under- or overnourished, and it is usually associated with an inflammation status, which can subsequently imply a different health status, as the risk of infection is increased, along with a deterioration of the immune system. Children's immune systems are generally more susceptible to problems than adults. In the situation of malnutrition, because malnourished children's immune systems are compromised, they are more likely to die. However, little is known about the underlying mechanism of altered immune functioning and how it relates to starvation. Nutritional interventions have been reported as cost-effective strategies to prevent or treat the development of malnourishment, considering the link between food intake and health, especially in children, and also the susceptibility of this population to diseases and how their health status during childhood might affect their long-term physiological growth. The ingestion of specific nutrients (e.g., vitamins or oligoelements) has been reported to contribute to the proper functioning of children's immune systems. In this review, we aim to describe the basis of malnutrition and how this is linked to the immune system, considering the role of nutrients in the modulation of the immune system and the risk of infection that can occur in these situations in children, as well as to identify nutritional interventions to improve their health.
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Desnutrición , Inanición , Adulto , Niño , Humanos , Salud Infantil , Estado de Salud , Sistema InmunológicoRESUMEN
As in other parts of the world, undocumented migrants in Italy suffer worse health status due to their immigration enforcement situation and other vulnerabilities such as precarious illegal jobs, exploitation and abuse or barriers to higher education, with higher prevalence of chronic noncommunicable diseases. The COVID-19 pandemic, as other pandemics, has not affected everyone equally. The undocumented was one of the most affected groups with regard to hospitalization rates and mortality worldwide. Sicily is one of the gates of entrance to Europe for migrants and asylum seekers from Africa and Asia. Herein, we described the epidemiological characteristics of COVID-19 cases in Sicily to compare hospitalization rate and mortality between Italian nationals and foreigners. We extracted data from the integrated national surveillance system established by the Italian National Institute of Health (Istituto Superiore di Sanità, ISS) to collect information on all COVID-19 cases and deaths in Sicily. We found that the hospitalization rates were higher in undocumented foreigners, and they were most likely to present a more severe clinical outcome compared to Italian nationals. Inclusive public health policies should take this population group into consideration to achieve the Health for All goal.
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COVID-19 , Refugiados , COVID-19/epidemiología , Hospitalización , Humanos , Italia/epidemiología , Pandemias , Sicilia/epidemiologíaRESUMEN
The gut microbiota is essential for maintenance and repair of the intestinal epithelial barrier. As shifts in both intestinal epithelial barrier function and microbiota composition are found in inflammatory bowel disease patients, it is critical to understand the role of distinct bacteria in regulating barrier repair. We identified a mouse commensal E. coli isolate, GDAR2-2, that protects mice from Citrobacter rodentium infection and dextran sulfate sodium-induced colitis. Colonization with GDAR2-2 in mice resulted in expansion of CX3CR1+ mononuclear phagocytes, including CX3CR1+ macrophages/dendritic cells and monocytes, along with IL-22-secreting type 3 innate lymphoid cells and improved epithelial barrier function. In vitro co-culture of macrophages with GDAR2-2 resulted in IL-1ß production. In vivo, protection after GDAR2-2 colonization was lost after depletion of CX3CR1+ MNPs, or blockade of IL-1ß or IL-22. We further identified human commensal E. coli isolates that similarly protect mice from C. rodentium infection through CX3CR1+ MNP and IL-1ß production. Together, these findings demonstrate an unexpected role for commensal bacteria in promoting IL-1ß secretion to support intestinal barrier repair.
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Colitis/metabolismo , Colitis/fisiopatología , Microbioma Gastrointestinal , Interleucina-18/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/microbiología , Simbiosis , Animales , Bacterias/clasificación , Bacterias/genética , Bacterias/aislamiento & purificación , Fenómenos Fisiológicos Bacterianos , Colitis/genética , Colitis/microbiología , Humanos , Interleucina-18/genética , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Macrófagos/metabolismo , Macrófagos/microbiología , Ratones , Ratones Endogámicos C57BLRESUMEN
Inflammatory bowel disease (IBD) is a chronic life-long inflammatory disease affecting almost 2 million Americans. Although new biologic therapies have been developed, the standard medical treatment fails to selectively control the dysregulated immune pathways involved in chronic colonic inflammation. Further, IBD patients with uncontrolled colonic inflammation are at a higher risk for developing colorectal cancer (CRC). Intestinal microbes can impact many immune functions, and here we asked if they could be used to improve intestinal inflammation. By utilizing an intestinal adherent E. coli that we find increases IL-10 producing macrophages, we were able to limit intestinal inflammation and restrict tumor formation. Macrophage IL-10 along with IL-10 signaling to the intestinal epithelium were required for protection in both inflammation and tumor development. Our work highlights that administration of immune modulating microbes can improve intestinal outcomes by altering tissue inflammation.
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Neoplasias Asociadas a Colitis , Colitis , Microbioma Gastrointestinal , Enfermedades Inflamatorias del Intestino , Microbiota , Animales , Modelos Animales de Enfermedad , Escherichia coli , Humanos , Inflamación , Enfermedades Inflamatorias del Intestino/terapia , Interleucina-10 , MacrófagosRESUMEN
During both health and disease, a coordinated response between the epithelium, immune system, and enteric nervous system is required for proper intestinal function. While each system responds to a number of common stimuli, their coordinated responses support digestion as well as responses and recovery following injury or pathogenic infections. In this review, we discuss how individual responses to common signals work together to support these critical functions.
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Sistema Nervioso Entérico/fisiología , Epitelio/fisiología , Microbioma Gastrointestinal , Interacciones Microbiota-Huesped , Inmunidad , Intestinos/inmunología , Intestinos/microbiología , Humanos , Mucosa Intestinal/fisiologíaRESUMEN
The Veterans Health Administration determined that over 250,000 U.S. service members were diagnosed with a traumatic brain injury (TBI) between 2008 and 2018, of which a great proportion were due to blast exposure. Although the penetrating (secondary) and inertia-driven (tertiary) phases of blast-induced TBI (bTBI) have been studied thoroughly and are known to be injurious, primary blast brain injury has been less studied. We investigated the biomechanics of primary bTBI in our previously developed in vitro shock tube model with a fluid-filled sample receiver. Using stereoscopic, high-speed cameras and digital image correlation (DIC), we mapped the deformation of organotypic hippocampal slice cultures (OHSCs) following a range of blast exposures to characterize the induced strains. As blast exposure increased, tissue strain increased, although the levels remained relatively low (maximum < 9%), with strains rates between 25 and 85 s-1. Both strain magnitude and rate were highly correlated with the in-air blast impulse and in-fluid peak pressure parameters. Comparing biomechanical parameters to previously reported blast-induced electrophysiological dysfunction, a threshold for deficits in long-term potentiation (LTP) was observed for strains between 3.7 and 6.7% and strain rates between 25 and 33 s-1. This is the first study to experimentally determine primary blast-induced strain and strain rates in hippocampal tissue.
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Traumatismos por Explosión/fisiopatología , Lesiones Encefálicas/fisiopatología , Hipocampo/fisiopatología , Animales , Fenómenos Biomecánicos , Muerte Celular , Explosiones , Análisis de Elementos Finitos , Procesamiento de Imagen Asistido por Computador , Potenciación a Largo Plazo , Ratas Sprague-Dawley , Grabación en VideoRESUMEN
An amendment to this paper has been published and can be accessed via a link at the top of the paper.
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Central nervous system ischemic injury features neuronal dysfunction, inflammation and breakdown of vascular integrity. Here we show that activation of endothelial caspase-9 after hypoxia-ischemia is a critical event in subsequent dysfunction of the blood-retina barrier, using a panel of interrelated ophthalmic in vivo imaging measures in a mouse model of retinal vein occlusion (RVO). Rapid nonapoptotic activation of caspase-9 and its downstream effector caspase-7 in endothelial cells promotes capillary ischemia and retinal neurodegeneration. Topical eye-drop delivery of a highly selective caspase-9 inhibitor provides morphological and functional retinal protection. Inducible endothelial-specific caspase-9 deletion phenocopies this protection, with attenuated retinal edema, reduced inflammation and preserved neuroretinal morphology and function following RVO. These results reveal a non-apoptotic function of endothelial caspase-9 which regulates blood-retina barrier integrity and neuronal survival, and identify caspase-9 as a therapeutic target in neurovascular disease.
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Caspasa 9/metabolismo , Hipoxia/metabolismo , Isquemia/metabolismo , Oclusión de la Vena Retiniana/metabolismo , Lesiones del Sistema Vascular/metabolismo , Animales , Barrera Hematorretinal/metabolismo , Caspasa 7/metabolismo , Caspasa 9/efectos de los fármacos , Caspasa 9/genética , Muerte Celular , Modelos Animales de Enfermedad , Células Endoteliales/metabolismo , Femenino , Predisposición Genética a la Enfermedad/genética , Inflamación/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Conejos , Retina/metabolismo , Retina/patología , Oclusión de la Vena Retiniana/tratamiento farmacológico , Oclusión de la Vena Retiniana/patología , Lesiones del Sistema Vascular/patologíaRESUMEN
Respiratory chemosensory circuits are implicated in several physiological and behavioral disorders ranging from sudden infant death syndrome to panic disorder. Thus, a comprehensive map of the chemosensory network would be of significant value. To delineate chemosensory neuronal populations, we have utilized pharmacogenetic Designer Receptors Exclusively Activated by Designer Drugs (DREADD) perturbations for acute neuronal perturbations in respiratory circuit mapping. Recent studies show that the biologically inert DREADD ligand clozapine-N-oxide (CNO) is back-metabolized into the bioactive compound clozapine in rodents, emphasizing the need for CNO-only DREADD-free controls, which have been carried out in several studies. However, we show that high CNO doses used in several chemosensory circuit mapping studies nonetheless affect the chemosensory ventilatory reflexes in control mice, which is unmasked by extensive habituation. Here, unhabituated control animals showed no differences in respiratory parameters after CNO administration, whereas habituated animals receiving the commonly used dose of 10 mg/kg of CNO show a deficit in the hypercapnic (high CO2) chemosensory reflex, which is not present in 1 mg/kg CNO treated or saline control groups. Our findings indicate that even in appropriately controlled studies, additional masked CNO off-target effects may exist and underscore the importance of using minimal doses of activating ligand in combination with high levels of habituation.