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1.
Cell ; 183(5): 1282-1297.e18, 2020 11 25.
Artículo en Inglés | MEDLINE | ID: mdl-33098771

RESUMEN

Classically considered short-lived and purely defensive leukocytes, neutrophils are unique in their fast and moldable response to stimulation. This plastic behavior may underlie variable and even antagonistic functions during inflammation or cancer, yet the full spectrum of neutrophil properties as they enter healthy tissues remains unexplored. Using a new model to track neutrophil fates, we found short but variable lifetimes across multiple tissues. Through analysis of the receptor, transcriptional, and chromatin accessibility landscapes, we identify varying neutrophil states and assign non-canonical functions, including vascular repair and hematopoietic homeostasis. Accordingly, depletion of neutrophils compromised angiogenesis during early age, genotoxic injury, and viral infection, and impaired hematopoietic recovery after irradiation. Neutrophils acquired these properties in target tissues, a process that, in the lungs, occurred in CXCL12-rich areas and relied on CXCR4. Our results reveal that tissues co-opt neutrophils en route for elimination to induce programs that support their physiological demands.


Asunto(s)
Linaje de la Célula , Neutrófilos/metabolismo , Especificidad de Órganos , Animales , Cromatina/metabolismo , Femenino , Hematopoyesis , Intestinos/irrigación sanguínea , Pulmón/irrigación sanguínea , Masculino , Ratones Endogámicos C57BL , Neovascularización Fisiológica , Miembro 1 del Grupo A de la Subfamilia 4 de Receptores Nucleares/metabolismo , Receptores CXCR4/metabolismo , Análisis de la Célula Individual , Transcripción Genética , Transcriptoma/genética
2.
Cell ; 183(1): 94-109.e23, 2020 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-32937105

RESUMEN

Cardiomyocytes are subjected to the intense mechanical stress and metabolic demands of the beating heart. It is unclear whether these cells, which are long-lived and rarely renew, manage to preserve homeostasis on their own. While analyzing macrophages lodged within the healthy myocardium, we discovered that they actively took up material, including mitochondria, derived from cardiomyocytes. Cardiomyocytes ejected dysfunctional mitochondria and other cargo in dedicated membranous particles reminiscent of neural exophers, through a process driven by the cardiomyocyte's autophagy machinery that was enhanced during cardiac stress. Depletion of cardiac macrophages or deficiency in the phagocytic receptor Mertk resulted in defective elimination of mitochondria from the myocardial tissue, activation of the inflammasome, impaired autophagy, accumulation of anomalous mitochondria in cardiomyocytes, metabolic alterations, and ventricular dysfunction. Thus, we identify an immune-parenchymal pair in the murine heart that enables transfer of unfit material to preserve metabolic stability and organ function. VIDEO ABSTRACT.


Asunto(s)
Macrófagos/metabolismo , Mitocondrias/metabolismo , Miocitos Cardíacos/metabolismo , Anciano , Animales , Apoptosis , Autofagia , Femenino , Corazón/fisiología , Homeostasis , Humanos , Macrófagos/fisiología , Masculino , Ratones , Ratones Endogámicos C57BL , Persona de Mediana Edad , Mitocondrias/fisiología , Infarto del Miocardio/metabolismo , Miocardio/metabolismo , Miocitos Cardíacos/fisiología , Fagocitosis/fisiología , Especies Reactivas de Oxígeno/metabolismo , Proteínas Tirosina Quinasas Receptoras/metabolismo , Tirosina Quinasa c-Mer/metabolismo
3.
Immunity ; 50(2): 390-402.e10, 2019 02 19.
Artículo en Inglés | MEDLINE | ID: mdl-30709741

RESUMEN

Neutrophils eliminate pathogens efficiently but can inflict severe damage to the host if they over-activate within blood vessels. It is unclear how immunity solves the dilemma of mounting an efficient anti-microbial defense while preserving vascular health. Here, we identify a neutrophil-intrinsic program that enabled both. The gene Bmal1 regulated expression of the chemokine CXCL2 to induce chemokine receptor CXCR2-dependent diurnal changes in the transcriptional and migratory properties of circulating neutrophils. These diurnal alterations, referred to as neutrophil aging, were antagonized by CXCR4 (C-X-C chemokine receptor type 4) and regulated the outer topology of neutrophils to favor homeostatic egress from blood vessels at night, resulting in boosted anti-microbial activity in tissues. Mice engineered for constitutive neutrophil aging became resistant to infection, but the persistence of intravascular aged neutrophils predisposed them to thrombo-inflammation and death. Thus, diurnal compartmentalization of neutrophils, driven by an internal timer, coordinates immune defense and vascular protection.


Asunto(s)
Vasos Sanguíneos/inmunología , Ritmo Circadiano/inmunología , Neutrófilos/inmunología , Fagocitosis/inmunología , Animales , Vasos Sanguíneos/metabolismo , Candida albicans/inmunología , Candida albicans/fisiología , Células Cultivadas , Senescencia Celular/inmunología , Quimiocina CXCL2/inmunología , Quimiocina CXCL2/metabolismo , Interacciones Huésped-Patógeno/inmunología , Humanos , Inflamación/inmunología , Inflamación/metabolismo , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Infiltración Neutrófila/inmunología , Neutrófilos/metabolismo , Neutrófilos/microbiología , Receptores CXCR4/inmunología , Receptores CXCR4/metabolismo , Factores de Tiempo
4.
PLoS Biol ; 21(11): e3002389, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37983289

RESUMEN

The meningeal space is a critical brain structure providing immunosurveillance for the central nervous system (CNS), but the impact of infections on the meningeal immune landscape is far from being fully understood. The extracellular protozoan parasite Trypanosoma brucei, which causes human African trypanosomiasis (HAT) or sleeping sickness, accumulates in the meningeal spaces, ultimately inducing severe meningitis and resulting in death if left untreated. Thus, sleeping sickness represents an attractive model to study immunological dynamics in the meninges during infection. Here, by combining single-cell transcriptomics and mass cytometry by time-of-flight (CyTOF) with in vivo interventions, we found that chronic T. brucei infection triggers the development of ectopic lymphoid aggregates (ELAs) in the murine meninges. These infection-induced ELAs were defined by the presence of ER-TR7+ fibroblastic reticular cells, CD21/35+ follicular dendritic cells (FDCs), CXCR5+ PD1+ T follicular helper-like phenotype, GL7+ CD95+ GC-like B cells, and plasmablasts/plasma cells. Furthermore, the B cells found in the infected meninges produced high-affinity autoantibodies able to recognise mouse brain antigens, in a process dependent on LTß signalling. A mid-throughput screening identified several host factors recognised by these autoantibodies, including myelin basic protein (MBP), coinciding with cortical demyelination and brain pathology. In humans, we identified the presence of autoreactive IgG antibodies in the cerebrospinal fluid (CSF) of second stage HAT patients that recognised human brain lysates and MBP, consistent with our findings in experimental infections. Lastly, we found that the pathological B cell responses we observed in the meninges required the presence of T. brucei in the CNS, as suramin treatment before the onset of the CNS stage prevented the accumulation of GL7+ CD95+ GC-like B cells and brain-specific autoantibody deposition. Taken together, our data provide evidence that the meningeal immune response during chronic T. brucei infection results in the acquisition of lymphoid tissue-like properties, broadening our understanding of meningeal immunity in the context of chronic infections. These findings have wider implications for understanding the mechanisms underlying the formation ELAs during chronic inflammation resulting in autoimmunity in mice and humans, as observed in other autoimmune neurodegenerative disorders, including neuropsychiatric lupus and multiple sclerosis.


Asunto(s)
Trypanosoma brucei brucei , Tripanosomiasis Africana , Humanos , Animales , Ratones , Infección Persistente , Meninges/metabolismo , Tejido Linfoide/metabolismo , Autoanticuerpos
5.
Nature ; 572(7771): 670-675, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31391580

RESUMEN

Macrophages are considered to contribute to chronic inflammatory diseases such as rheumatoid arthritis1. However, both the exact origin and the role of macrophages in inflammatory joint disease remain unclear. Here we use fate-mapping approaches in conjunction with three-dimensional light-sheet fluorescence microscopy and single-cell RNA sequencing to perform a comprehensive spatiotemporal analysis of the composition, origin and differentiation of subsets of macrophages within healthy and inflamed joints, and study the roles of these macrophages during arthritis. We find that dynamic membrane-like structures, consisting of a distinct population of CX3CR1+ tissue-resident macrophages, form an internal immunological barrier at the synovial lining and physically seclude the joint. These barrier-forming macrophages display features that are otherwise typical of epithelial cells, and maintain their numbers through a pool of locally proliferating CX3CR1- mononuclear cells that are embedded into the synovial tissue. Unlike recruited monocyte-derived macrophages, which actively contribute to joint inflammation, these epithelial-like CX3CR1+ lining macrophages restrict the inflammatory reaction by providing a tight-junction-mediated shield for intra-articular structures. Our data reveal an unexpected functional diversification among synovial macrophages and have important implications for the general role of macrophages in health and disease.


Asunto(s)
Articulaciones/citología , Macrófagos/citología , Macrófagos/fisiología , Membrana Sinovial/citología , Sinoviocitos/citología , Sinoviocitos/fisiología , Uniones Estrechas/fisiología , Animales , Artritis/inmunología , Artritis/patología , Receptor 1 de Quimiocinas CX3C/análisis , Receptor 1 de Quimiocinas CX3C/metabolismo , Rastreo Celular , Femenino , Perfilación de la Expresión Génica , Humanos , Inflamación/inmunología , Inflamación/patología , Articulaciones/patología , Macrófagos/clasificación , Macrófagos/metabolismo , Masculino , Ratones , Ratones Endogámicos C57BL , Análisis de Componente Principal , RNA-Seq , Análisis de la Célula Individual , Sinoviocitos/clasificación , Sinoviocitos/metabolismo , Transcriptoma/genética
6.
PLoS Pathog ; 17(11): e1010060, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34780575

RESUMEN

Human African Trypanosomiasis (HAT) has been responsible for several deadly epidemics throughout the 20th century, but a renewed commitment to disease control has significantly reduced new cases and motivated a target for the elimination of Trypanosoma brucei gambiense-HAT by 2030. However, the recent identification of latent human infections, and the detection of trypanosomes in extravascular tissues hidden from current diagnostic tools, such as the skin, has added new complexity to identifying infected individuals. New and improved diagnostic tests to detect Trypanosoma brucei infection by interrogating the skin are therefore needed. Recent advances have improved the cost, sensitivity and portability of Raman spectroscopy technology for non-invasive medical diagnostics, making it an attractive tool for gambiense-HAT detection. The aim of this work was to assess and develop a new non-invasive diagnostic method for T. brucei through Raman spectroscopy of the skin. Infections were performed in an established murine disease model using the animal-infective Trypanosoma brucei brucei subspecies. The skin of infected and matched control mice was scrutinized ex vivo using a confocal Raman microscope with 532 nm excitation and in situ at 785 nm excitation with a portable field-compatible instrument. Spectral evaluation and Principal Component Analysis confirmed discrimination of T. brucei-infected from uninfected tissue, and a characterisation of biochemical changes in lipids and proteins in parasite-infected skin indicated by prominent Raman peak intensities was performed. This study is the first to demonstrate the application of Raman spectroscopy for the detection of T. brucei by targeting the skin of the host. The technique has significant potential to discriminate between infected and non-infected tissue and could represent a unique, non-invasive diagnostic tool in the goal for elimination of gambiense-HAT as well as for Animal African Trypanosomiasis (AAT).


Asunto(s)
Piel/patología , Espectrometría Raman/métodos , Trypanosoma brucei brucei/fisiología , Trypanosoma brucei gambiense/fisiología , Tripanosomiasis Africana/diagnóstico , Animales , Femenino , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Piel/parasitología , Tripanosomiasis Africana/parasitología
8.
Biometals ; 36(3): 463-472, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36474100

RESUMEN

Lactoferrin (LF) has in vitro antiviral activity against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This study aimed to determine the effect of bovine lactoferrin (bLF) in the prevention of SARS-CoV-2 infection in health care personnel. A randomized, double-blinded, placebo-controlled clinical trial was conducted in two tertiary hospitals that provide care to patients with SARS-CoV-2 infection in Lima, Peru. Daily supplementation with 600 mg of enteral bLF versus placebo for 90 days was compared. Participants were weekly screened for symptoms suggestive of SARS-CoV-2 infection and molecular testing was performed on suspected episodes. A serological test was obtained from all participants at the end of the intervention. The main outcome included symptomatic and asymptomatic cases. A sub-analysis explored the time to symptomatic infection. Secondary outcomes were the severity, frequency, and duration of symptomatic infection. The study was prematurely cancelled due to the availability of vaccines against SARS-CoV-2 in Peru. 209 participants were enrolled and randomized, 104 received bLF and 105 placebo. SARS-CoV-2 infection occurred in 11 (10.6%) participants assigned to bLF and in 9 (8.6%) participants assigned to placebo without significant differences (Incidence Rate Ratio = 1.23, 95%CI 0.51-3.06, p-value = 0.64). There was no significant effect of bLF on time to symptomatic infection (Hazard Ratio = 1.61, 95%CI 0.62-4.19, p-value = 0.3). There were no significant differences in secondary outcomes. A significant effect of bLF in preventing SARS-CoV-2 infection was not proven. Further studies are needed to assess the effect of bLF supplementation on SARS-CoV-2 infection.Clinical trial registration ClinicalTrials.gov Identifier: NCT04526821, https://clinicaltrials.gov/ct2/show/NCT04526821?term=LACTOFERRIN&cond=COVID-19&cntry=PE&city=Lima&draw=2&rank=1 .


Asunto(s)
COVID-19 , Lactoferrina , Humanos , COVID-19/prevención & control , Vacunas contra la COVID-19 , Atención a la Salud , Hidroxicloroquina/uso terapéutico , Lactoferrina/uso terapéutico , SARS-CoV-2
9.
Neuropsychobiology ; 81(4): 271-285, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35093946

RESUMEN

INTRODUCTION: Major depressive disorder (MDD) is a prevalent condition which has a well-known association with ischemic cardiomyopathy, probably explained by an inflammatory mediator mechanism. Statins, besides reducing cholesterol production, have pleiotropic effects including anti-inflammatory activity. The goal was to evaluate the effect of statins as an addition to standard therapy on mood status, brain perfusion, and neurocognitive performance in MDD. METHODS: We studied 20 MDD patients with brain single-photon emission tomography and Cambridge Neuropsychological Test Automated Battery (CANTAB), half randomized to 10 mg of Rosuvastatin or placebo, in addition to selective serotonin reuptake inhibitors (SSRIs) therapy and being reevaluated 3 months later. The images were compared using Statistical Parametric Mapping; clinical scores (Hamilton Depression Score with 17 items and Beck's Depression Inventory) as well as neurocognitive parameters were applied as covariances (CoV) to estimate regional cerebral blood flow (rCBF) changes with both therapies. RESULTS: Clinical scores decreased in both groups (p = 0.0001); Beck's presented a larger decrease with statins. We observed significantly rCBF changes expressed as significant larger clusters of voxels (p < 0.05) in the pre/subgenual anterior cingulate plus orbitofrontal cortex and a small area in the posterior cingulate gyrus in the statins group, whereas it was not observed with placebo, when using clinical scores as CoV. A similar pattern of rCBF changes was present with emotions recognition, attentional, paired associates learning, spatial planning, and working memory tasks. CONCLUSION: Short-term use of low-dose statins in MDD patients under SSRIs results in important rCBF changes in key mood associated areas to improvement in neurocognitive performance. These findings, even though demonstrated in a small sample, could open a new therapeutic tool in the comprehensive management of this disorder.


Asunto(s)
Trastorno Depresivo Mayor , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Encéfalo/diagnóstico por imagen , Circulación Cerebrovascular/fisiología , Trastorno Depresivo Mayor/diagnóstico por imagen , Trastorno Depresivo Mayor/tratamiento farmacológico , Giro del Cíngulo , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/farmacología , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Perfusión , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Inhibidores Selectivos de la Recaptación de Serotonina/uso terapéutico , Tomografía Computarizada de Emisión de Fotón Único/métodos
10.
Cogn Process ; 23(1): 27-40, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-34779948

RESUMEN

Scene analysis in video sequences is a complex task for a computer vision system. Several schemes have been addressed in this analysis, such as deep learning networks or traditional image processing methods. However, these methods require thorough training or manual adjustment of parameters to achieve accurate results. Therefore, it is necessary to develop novel methods to analyze the scenario information in video sequences. For this reason, this paper proposes a method for object segmentation in video sequences inspired by the structural layers of the visual cortex. The method is called Neuro-Inspired Object Segmentation, SegNI. SegNI has a hierarchical architecture that analyzes object features such as edges, color, and motion to generate regions that represent the objects in the scenario. The results obtained with the Video Segmentation Benchmark VSB100 dataset demonstrate that SegNI can adapt automatically to videos with scenarios that have different nature, composition, and different types of objects. Also, SegNI adapts its processing to new scenario conditions without training, which is a significant advantage over deep learning networks.


Asunto(s)
Algoritmos , Corteza Visual , Inteligencia Artificial , Humanos , Procesamiento de Imagen Asistido por Computador , Movimiento (Física)
11.
Protein Expr Purif ; 183: 105877, 2021 07.
Artículo en Inglés | MEDLINE | ID: mdl-33775769

RESUMEN

The Leishmania major leucyl-aminopeptidase (LAPLm), a member of the M17 family of proteases, is a potential drug target for treatment of leishmaniasis. To better characterize enzyme properties, recombinant LAPLm (rLAPLm) was expressed in Escherichia coli. A LAPLm gene was designed, codon-optimized for expression in E. coli, synthesized and cloned into the pET-15b vector. Production of rLAPLm in E. coli Lemo21(DE3), induced for 4 h at 37 °C with 400 µM IPTG and 250 µM l-rhamnose, yielded insoluble enzyme with a low proportion of soluble and active protein, only detected by an anti-His antibody-based western-blot. rLAPLm was purified in a single step by immobilized metal ion affinity chromatography. rLAPLm was obtained with a purity of ~10% and a volumetric yield of 2.5 mg per liter, sufficient for further characterization. The aminopeptidase exhibits optimal activity at pH 7.0 and a substrate preference for Leu-p-nitroanilide (appKM = 30 µM, appkcat = 14.7 s-1). Optimal temperature is 50 °C, and the enzyme is insensitive to 4 mM Co2+, Mg2+, Ca2+ and Ba2+. However, rLAPLm was activated by Zn2+, Mn2+ and Cd2+ but is insensitive towards the protease inhibitors PMSF, TLCK, E-64 and pepstatin A, being inhibited by EDTA and bestatin. Bestatin is a potent, non-competitive inhibitor of the enzyme with a Ki value of 994 nM. We suggest that rLAPLm is a suitable target for inhibitor identification.


Asunto(s)
Aminopeptidasas , Escherichia coli , Leishmania major , Proteínas Protozoarias , Aminopeptidasas/biosíntesis , Aminopeptidasas/química , Aminopeptidasas/genética , Aminopeptidasas/aislamiento & purificación , Escherichia coli/genética , Escherichia coli/metabolismo , Cinética , Leishmania major/enzimología , Leishmania major/genética , Proteínas Protozoarias/biosíntesis , Proteínas Protozoarias/química , Proteínas Protozoarias/genética , Proteínas Protozoarias/aislamiento & purificación , Proteínas Recombinantes/biosíntesis , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/aislamiento & purificación
12.
Neuropsychobiology ; 80(3): 214-224, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32726779

RESUMEN

BACKGROUND: Major depressive disorder (MDD) is an important independent risk factor for cardiovascular disease. Cumulative data suggest that depressive patients exhibit derangement in regional cerebral blood flow (rCBF), although underlying mechanisms remain mostly unknown. Endothelial dysfunction (ED), defined as different forms of abnormal endothelial activity, plays a key role in the pathogenesis of vascular disease. ED is associated with several clinical conditions characterized by high cardiovascular risk. Diverse ED markers have been found in mood disorders. PURPOSE: To evaluate the association between rCBF and peripheral ED markers in MDD patients, at baseline and after selective serotonin receptor inhibitors (SSRIs) therapy. PATIENTS AND METHODS: Twenty-seven untreated unipolar MDD patients in their first episode were evaluated with the Hamilton Depression Rating Scale (HAM-D) and brain perfusion SPECT at baseline and after 2 months of SSRIs. Statistical Parametric Mapping (SPM) was employed to evaluate rCBF; circulating endothelial cells (CECs), plasma soluble intercellular adhesion molecule (sICAM), and high-sensitivity C-reactive protein (hsCRP) were used as independent covariates. RESULTS: Baseline CECs and sICAM were increased in MDD patients compared with matching controls (p = 0.0001) and hsCRP (p = 0.03). HAM-D scores (21 items) and CECs diminished after SSRI therapy in MDD patients (p < 0.0001). There was a significant rCBF decrease, mainly in deep central structures. HAM-D change was associated with rCBF decrease at the left amygdala, right striatum levels, and Brodmann area 25. CEC change was associated with rCBF at deep brain level and sICAM with large rCBF areas at the left caudate and tectum; hsCRP was associated, to a lesser extent, with the left dorsal striatum and mesencephalic tectum. CONCLUSION: ED markers in patients with MDD are associated with significant changes in rCBF which are features of depression. These findings suggest that systemic damage/activation of the endothelium may contribute to the abnormal rCBF observed in MDD patients.


Asunto(s)
Circulación Cerebrovascular/fisiología , Trastorno Depresivo Mayor/sangre , Trastorno Depresivo Mayor/tratamiento farmacológico , Trastorno Depresivo Mayor/fisiopatología , Endotelio Vascular/fisiopatología , Flujo Sanguíneo Regional/fisiología , Inhibidores Selectivos de la Recaptación de Serotonina/farmacología , Adulto , Circulación Cerebrovascular/efectos de los fármacos , Trastorno Depresivo Mayor/diagnóstico por imagen , Endotelio Vascular/efectos de los fármacos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Resultado en la Atención de Salud , Flujo Sanguíneo Regional/efectos de los fármacos , Tomografía Computarizada de Emisión de Fotón Único , Adulto Joven
13.
Parasitology ; 148(10): 1137-1142, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-33602349

RESUMEN

Aquaglyceroporins (AQPs) are membrane proteins that function in osmoregulation and the uptake of low molecular weight solutes, in particular glycerol and urea. The AQP family is highly conserved, with two major subfamilies having arisen very early in prokaryote evolution and retained by eukaryotes. A complex evolutionary history indicates multiple lineage-specific expansions, losses and not uncommonly a complete loss. Consequently, the AQP family is highly evolvable and has been associated with significant events in life on Earth. In the African trypanosomes, a role for the AQP2 paralogue, in sensitivity to two chemotherapeutic agents, pentamidine and melarsoprol, is well established, albeit with the mechanisms for cell entry and resistance unclear until very recently. Here, we discuss AQP evolution, structure and mechanisms by which AQPs impact drug sensitivity, suggesting that AQP2 stability is highly sensitive to mutation while serving as the major uptake pathway for pentamidine.


Asunto(s)
Acuagliceroporinas/genética , Resistencia a Medicamentos/genética , Proteínas Protozoarias/genética , Tripanocidas/farmacología , Trypanosoma/efectos de los fármacos , Trypanosoma/metabolismo
14.
Rev Med Chil ; 149(6): 888-898, 2021 Jun.
Artículo en Español | MEDLINE | ID: mdl-34751348

RESUMEN

Neuroendocrine Tumors (NETs) encompass a wide variety of tumors arising from neuroendocrine cells, which produce bioactive substances. The incidence of NETs increased significantly lately, becoming one of the most common tumors of the digestive tract. Their clinical presentation is as diverse as their capacity for hormone production. Carcinoid syndrome is the most common hormonal syndrome produced by NETs and is characterized by diarrhea, flushing and cardiac valvular lesions. New research brought multiple changes in the classification of these neoplasms and a new understanding about their diagnosis and treatment, promoting a multidisciplinary approach. Somatostatin analogues, radiation, biological, and cytotoxic drugs have improved the prognosis of these patients, which entails a great challenge for healthcare providers.


Asunto(s)
Antineoplásicos , Tumores Neuroendocrinos , Antineoplásicos/uso terapéutico , Diarrea , Humanos , Tumores Neuroendocrinos/diagnóstico , Tumores Neuroendocrinos/terapia , Somatostatina/uso terapéutico
15.
PLoS Biol ; 13(7): e1002210, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26172158

RESUMEN

Drosophila melanogaster is a valuable invertebrate model for viral infection and antiviral immunity, and is a focus for studies of insect-virus coevolution. Here we use a metagenomic approach to identify more than 20 previously undetected RNA viruses and a DNA virus associated with wild D. melanogaster. These viruses not only include distant relatives of known insect pathogens but also novel groups of insect-infecting viruses. By sequencing virus-derived small RNAs, we show that the viruses represent active infections of Drosophila. We find that the RNA viruses differ in the number and properties of their small RNAs, and we detect both siRNAs and a novel miRNA from the DNA virus. Analysis of small RNAs also allows us to identify putative viral sequences that lack detectable sequence similarity to known viruses. By surveying >2,000 individually collected wild adult Drosophila we show that more than 30% of D. melanogaster carry a detectable virus, and more than 6% carry multiple viruses. However, despite a high prevalence of the Wolbachia endosymbiont--which is known to be protective against virus infections in Drosophila--we were unable to detect any relationship between the presence of Wolbachia and the presence of any virus. Using publicly available RNA-seq datasets, we show that the community of viruses in Drosophila laboratories is very different from that seen in the wild, but that some of the newly discovered viruses are nevertheless widespread in laboratory lines and are ubiquitous in cell culture. By sequencing viruses from individual wild-collected flies we show that some viruses are shared between D. melanogaster and D. simulans. Our results provide an essential evolutionary and ecological context for host-virus interaction in Drosophila, and the newly reported viral sequences will help develop D. melanogaster further as a model for molecular and evolutionary virus research.


Asunto(s)
Evolución Biológica , Drosophila melanogaster/virología , Secuencia de Aminoácidos , Animales , Secuencia Conservada , Drosophila simulans/virología , Femenino , Masculino , Metagenómica , Datos de Secuencia Molecular , ARN/análisis , Interferencia de ARN , Proteínas Virales/química , Wolbachia/aislamiento & purificación
16.
Clin Immunol ; 173: 117-120, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27693481

RESUMEN

Antibody deficiencies can be caused by a variety of defects that interfere with B-cell development, maturation, and/or function. Using whole-exome sequencing we found a PIK3R1 mutation in a patient with hypogammaglobulinemia and a narrow clinical phenotype of respiratory infections. Early diagnosis is crucial; careful analysis of B and T-cells followed by genetic analyses may help to distinguish activated PI3K-delta syndrome (APDS) from other, less severe, predominantly antibody deficiencies.


Asunto(s)
Agammaglobulinemia/genética , Fosfatidilinositol 3-Quinasas/genética , Infecciones del Sistema Respiratorio/genética , Agammaglobulinemia/inmunología , Linfocitos B/inmunología , Niño , Fosfatidilinositol 3-Quinasa Clase Ia , Femenino , Humanos , Mutación , Fenotipo , Infecciones del Sistema Respiratorio/inmunología , Linfocitos T/inmunología
18.
Ann Hepatol ; 14(5): 752-5, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26256906

RESUMEN

Gastrointestinal neuroendocrine tumors (NET) frequently present with unresectable hepatic metastases, which poses a barrier for curative treatment. Resection of the primary tumor and subsequent orthotopic liver transplantation (OLT) has been proposed as a treatment approach but available data in this regard is limited. We present a clinical case of an otherwise asymptomatic 44-yo man complaining of abdominal pain and dyspepsia that was diagnosed of a 10 cm duodenal tumor with multiple hepatic metastases. A CT-guided biopsy confirmed a NET. He underwent first a Whipple's procedure, and then was listed for liver transplantation. During the waiting time a multimodal therapeutic approach was used including the use of radioactive 177lutetium-labeled somatostatin analogues, long-acting somastostatin analogues and antiangiogenic antibodies (bevacizumab) in order to keep neoplastic disease under control. Two years after Whipple's procedure and given disease stability he underwent OLT with an uneventful postoperative evolution. Patient condition and graft function are optimal after a 4-year follow-up period with no evidence of recurrence. This case report underscores how a multimodal approach involving careful patient selection, resective surgery as well as use of somatostatin analogues and antiangiogenic biological therapy followed by liver transplantation can achieve excellent long-term results in this difficult patient population.


Asunto(s)
Inhibidores de la Angiogénesis/uso terapéutico , Bevacizumab/uso terapéutico , Neoplasias Duodenales/cirugía , Neoplasias Hepáticas/terapia , Trasplante de Hígado , Tumores Neuroendocrinos/terapia , Radiofármacos/uso terapéutico , Somatostatina/uso terapéutico , Adulto , Biomarcadores de Tumor/análisis , Quimioradioterapia Adyuvante , Neoplasias Duodenales/química , Neoplasias Duodenales/patología , Humanos , Inmunohistoquímica , Neoplasias Hepáticas/química , Neoplasias Hepáticas/secundario , Imagen por Resonancia Magnética , Masculino , Tumores Neuroendocrinos/química , Tumores Neuroendocrinos/secundario , Tomografía de Emisión de Positrones , Somatostatina/análogos & derivados , Sinaptofisina/análisis , Factores de Tiempo , Tomografía Computarizada por Rayos X , Resultado del Tratamiento , Listas de Espera
19.
J Card Fail ; 20(3): 149-54, 2014 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-24412523

RESUMEN

OBJECTIVES: Heart failure (HF) is associated with changes in myocardial metabolism that lead to impairment of contractile function. Trimetazidine (TMZ) modulates cardiac energetic efficiency and improves outcomes in ischemic heart disease. We evaluated the effects of TMZ on left ventricular ejection fraction (LVEF), cardiac metabolism, exercise capacity, O2 uptake, and quality of life in patients with nonischemic HF. METHODS AND RESULTS: Sixty patients with stable nonischemic HF under optimal medical therapy were included in this randomized double-blind study. Patients were randomized to TMZ (35 mg orally twice a day) or placebo for 6 months. LVEF, 6-minute walk test (6MWT), maximum O2 uptake in cardiopulmonary exercise test, different markers of metabolism, oxidative stress, and endothelial function, and quality of life were assessed at baseline and after TMZ treatment. Left ventricular peak glucose uptake was evaluated with the use of the maximum standardized uptake value (SUV) by 18-fluorodeoxyglucose positron emission tomography ((18)FDG-PET). Etiology was idiopathic in 85% and hypertensive in 15%. Both groups were similar in age, functional class, LVEF, and levels of N-terminal pro-B-type natriuretic peptide at baseline. After 6 months of TMZ treatment, no changes were observed in LVEF (31 ± 10% vs 34 ± 8%; P = .8), 6MWT (443 ± 25 m vs 506 ± 79 m; P = .03), maximum O2 uptake (19.1 ± 5.0 mL kg(-1) min(-1) vs 23.0 ± 7.2 mL kg(-1) min(-1); P = .11), functional class (percentages of patients in functional classes I/II/III/IV 10/3753/0 vs 7/40/50/3; P = .14), or quality of life (32 ± 26 points vs 24 ± 18 points; P = .25) in TMZ versus placebo, respectively. In the subgroup of patients evaluated with (18)FDG-PET, no significant differences were observed in SUV between both groups (7.0 ± 3.6 vs 8.2 ± 3.4 respectively; P = .47). CONCLUSIONS: In patients with nonischemic HF, the addition of TMZ to optimal medical treatment does not result in significant changes of LVEF, exercise capacity, O2 uptake, or quality of life.


Asunto(s)
Insuficiencia Cardíaca/diagnóstico por imagen , Insuficiencia Cardíaca/tratamiento farmacológico , Isquemia Miocárdica , Trimetazidina/uso terapéutico , Vasodilatadores/uso terapéutico , Adulto , Anciano , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Cintigrafía , Resultado del Tratamiento
20.
AANA J ; 92(3): 207-210, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38758715

RESUMEN

The purpose of this study was to investigate whether the combination of intrathecal dexamethasone and dexmedetomidine in combination with bupivacaine in spinal anesthesia is effective for reducing nausea, vomiting, shivering, and pain. A retrospective review of records was used to examine the outcomes of patients undergoing cesarean delivery under spinal anesthesia with dexamethasone, dexmedetomidine, and bupivacaine. The records of 11 consecutive patients who underwent cesarean delivery under spinal anesthesia with intrathecal dexamethasone and dexmedetomidine in combination with bupivacaine were evaluated. Data collected included patient demographics, medications and fluids administered, presence of nausea, vomiting, shivering, intraoperative breakthrough pain, and postoperative pain. There were no reported complications related to the administration of intrathecal dexamethasone and dexmedetomidine in combination with bupivacaine in this case series of patients. No patients required treatment for intraoperative vomiting, shivering, or breakthrough pain. One patient required opioid pain medication postoperatively. This case series demonstrates that the administration of intrathecal dexamethasone and dexmedetomidine in combination with bupivacaine for patients undergoing elective cesarean section appears to be safe and offers some advantages as to traditional methods of intrathecal delivery for this surgical procedure.


Asunto(s)
Anestesia Raquidea , Anestésicos Locales , Bupivacaína , Cesárea , Dexametasona , Dexmedetomidina , Inyecciones Espinales , Humanos , Dexmedetomidina/administración & dosificación , Dexametasona/administración & dosificación , Femenino , Bupivacaína/administración & dosificación , Embarazo , Adulto , Estudios Retrospectivos , Anestésicos Locales/administración & dosificación , Dolor Postoperatorio/tratamiento farmacológico , Dolor Postoperatorio/prevención & control , Enfermeras Anestesistas , Anestesia Obstétrica , Náusea y Vómito Posoperatorios/prevención & control , Náusea y Vómito Posoperatorios/inducido químicamente , Quimioterapia Combinada
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