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1.
Vaccines (Basel) ; 12(4)2024 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-38675807

RESUMEN

A number of studies have suggested that influenza vaccination can provide protection against COVID-19, but the underlying mechanisms that could explain this association are still unclear. In this study, the effect of the 2021/2022 seasonal influenza vaccination on the immune response to the booster dose of anti-SARS-CoV-2 vaccination was evaluated in a cohort of healthy individuals. A total of 113 participants were enrolled, 74 of whom had no prior COVID-19 diagnosis or significant comorbidities were considered for the analysis. Participants received the anti-influenza tetravalent vaccine and the booster dose of the anti-SARS-CoV-2 vaccine or the anti-SARS-CoV-2 vaccine alone. Blood was collected before and 4 weeks after each vaccination and 12 weeks after SARS-CoV-2 vaccination and analyzed for anti-flu and anti-spike-specific antibody titers and for in vitro influenza and SARS-CoV-2 neutralization capacity. Results indicated an increased reactivity in subjects who received both influenza and SARS-CoV-2 vaccinations compared to those who received only the SARS-CoV-2 vaccine, with sustained anti-spike antibody titers up to 12 weeks post-vaccination. Immune response to the influenza vaccine was evaluated, and individuals were stratified as high or low responders. High responders showed increased antibody titers against the SARS-CoV-2 vaccine both after 4 and 12 weeks post-vaccination. Conversely, individuals classified as low responders were less responsive to the SARS-CoV-2 vaccine. These data indicate that both external stimuli, such as influenza vaccination, and the host's intrinsic ability to respond to stimuli play a role in the response to the vaccine.

2.
Dig Liver Dis ; 56(1): 83-91, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-37574431

RESUMEN

BACKGROUND: In recent years, improvement of Health-Related Quality of Life (HRQoL) in Ulcerative colitis (UC) has become a relevant measure for treatment efficacy. METHODS: We report results from a multicenter prospective study in Italy investigating HRQoL in adult patients with UC treated with golimumab (GLM). Patients who had shown clinical response after a 6-week induction phase (w0), were followed for an additional 48 weeks (w48) (total 54-week treatment). RESULTS: Of the 159 patients enrolled 90 completed the study. Compared to values at the beginning of treatment (n = 137), significant improvements were observed for mean total Inflammatory Bowel Disease Questionnaire (IBDQ) scores at w0 (168.5) and w48 (181.7). Patients with baseline PMS above the median tended to have greater improvements in IBDQ at w0 (OR 2.037, p = 0.033) and w48 (OR 3.292, p = 0.027). Compared to beginning of GLM treatment, the mean Full Mayo Score (FMS) decreased by 5.9 points at w48, while mean Partial Mayo Score (PMS) decreased by 3.9 points at w0 and by 4.9 points at w48. CONCLUSIONS: GLM improved HRQoL, disease activity and inflammatory biomarkers in UC patients with moderate-to-severely active disease. The greater the burden of disease activity at baseline, the greater the improvement of HRQoL after 24 and 48 weeks of treatment.


Asunto(s)
Colitis Ulcerosa , Enfermedades Inflamatorias del Intestino , Adulto , Humanos , Colitis Ulcerosa/tratamiento farmacológico , Calidad de Vida , Estudios Prospectivos , Anticuerpos Monoclonales/uso terapéutico , Resultado del Tratamiento , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Índice de Severidad de la Enfermedad
4.
Nat Commun ; 11(1): 4994, 2020 10 05.
Artículo en Inglés | MEDLINE | ID: mdl-33020485

RESUMEN

Serogroup B meningococcus (MenB) is a leading cause of meningitis and sepsis across the world and vaccination is the most effective way to protect against this disease. 4CMenB is a multi-component vaccine against MenB, which is now licensed for use in subjects >2 months of age in several countries. In this study, we describe the development and use of an ad hoc protein microarray to study the immune response induced by the three major 4CMenB antigenic components (fHbp, NHBA and NadA) in individual sera from vaccinated infants, adolescents and adults. The resulting 4CMenB protein antigen fingerprinting allowed the identification of specific human antibody repertoire correlating with the bactericidal response elicited in each subject. This work represents an example of epitope mapping of the immune response induced by a multicomponent vaccine in different age groups with the identification of protective signatures. It shows the high flexibility of this microarray based methodology in terms of high-throughput information and minimal volume of biological samples needed.


Asunto(s)
Anticuerpos Antibacterianos/inmunología , Antígenos Bacterianos/inmunología , Infecciones Meningocócicas/inmunología , Vacunas Meningococicas/inmunología , Neisseria meningitidis Serogrupo B/inmunología , Adolescente , Adulto , Anticuerpos Antibacterianos/sangre , Niño , Preescolar , Mapeo Epitopo , Humanos , Lactante , Infecciones Meningocócicas/prevención & control , Biblioteca de Péptidos , Análisis por Matrices de Proteínas , Determinación de Anticuerpos Séricos Bactericidas , Adulto Joven
5.
Nat Commun ; 11(1): 3679, 2020 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-32778649

RESUMEN

Hydrothermal processes in impact environments on water-rich bodies such as Mars and Earth are relevant to the origins of life. Dawn mapping of dwarf planet (1) Ceres has identified similar deposits within Occator crater. Here we show using Dawn high-resolution stereo imaging and topography that Ceres' unique composition has resulted in widespread mantling by solidified water- and salt-rich mud-like impact melts with scattered endogenic pits, troughs, and bright mounds indicative of outgassing of volatiles and periglacial-style activity during solidification. These features are distinct from and less extensive than on Mars, indicating that Occator melts may be less gas-rich or volatiles partially inhibited from reaching the surface. Bright salts at Vinalia Faculae form thin surficial precipitates sourced from hydrothermal brine effusion at many individual sites, coalescing in several larger centers, but their ages are statistically indistinguishable from floor materials, allowing for but not requiring migration of brines from deep crustal source(s).

6.
J Geophys Res Planets ; 125(3): e2019JE006296, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-32714727

RESUMEN

Some years ago, the consensus was that asteroid (16) Psyche was almost entirely metal. New data on density, radar properties, and spectral signatures indicate that the asteroid is something perhaps even more enigmatic: a mixed metal and silicate world. Here we combine observations of Psyche with data from meteorites and models for planetesimal formation to produce the best current hypotheses for Psyche's properties and provenance. Psyche's bulk density appears to be between 3,400 and 4,100 kg m-3. Psyche is thus predicted to have between ~30 and ~60 vol% metal, with the remainder likely low-iron silicate rock and not more than ~20% porosity. Though their density is similar, mesosiderites are an unlikely analog to bulk Psyche because mesosiderites have far more iron-rich silicates than Psyche appears to have. CB chondrites match both Psyche's density and spectral properties, as can some pallasites, although typical pallasitic olivine contains too much iron to be consistent with the reflectance spectra. Final answers, as well as resolution of contradictions in the data set of Psyche physical properties, for example, the thermal inertia measurements, may not be resolved until the NASA Psyche mission arrives in orbit at the asteroid. Despite the range of compositions and formation processes for Psyche allowed by the current data, the science payload of the Psyche mission (magnetometers, multispectral imagers, neutron spectrometer, and a gamma-ray spectrometer) will produce data sets that distinguish among the models.

7.
Dig Liver Dis ; 52(8): 808-815, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32425733

RESUMEN

BACKGROUND: In Italy, the spread of the COVID-19 pandemic has stressed the entire healthcare system and required a huge re-organization of many Divisions, including those of Gastroenterology. AIMS: to assess the impact of COVID-19 pandemic on Gastroenterology Divisions across Italy. METHODS: All members of the Italian Society of Gastroenterology (SIGE) were invited to answer a web-based survey. RESULTS: Data of 121 hospitals from all 20 Italian regions were analyzed. Overall, 10.7% Gastroenterology Divisions have been converted to Covid Units. Outpatients consultations, endoscopic and ultrasound procedures were limited to urgencies and oncology indications in 85.1%, 96.2% and 72.2% of Units, respectively, and 46.7% of them suspended the screening for colorectal cancer. Moreover, 72.2% of the staff received a training for use of personal protective equipment, although 45.5% did not have sufficient devices for adequate replacement. Overall, 132 healthcare workers in 41 Gastroenterology Divisions were found to be infected. CONCLUSION: This is the first study to evaluate, at a country level, the impact of COVID-19 outbreak on Gastroenterology Divisions. Substantial changes of practice and reduction of procedures have been recorded in the entire country. The long-term impact of such modifications is difficult to estimate but potentially very risky for many digestive diseases.


Asunto(s)
Infecciones por Coronavirus/prevención & control , Gastroenterología/métodos , Gastroenterología/estadística & datos numéricos , Gastroenterología/normas , Control de Infecciones/normas , Pandemias/prevención & control , Neumonía Viral/prevención & control , Betacoronavirus , COVID-19 , Infecciones por Coronavirus/transmisión , Personal de Salud , Hospitales , Humanos , Control de Infecciones/métodos , Italia/epidemiología , Equipo de Protección Personal/normas , Neumonía Viral/transmisión , SARS-CoV-2 , Encuestas y Cuestionarios
8.
Tech Coloproctol ; 23(2): 101-115, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30631977

RESUMEN

Pelvic floor rehabilitation is frequently recommended for defecation disorders, in both constipation and fecal incontinence. However, the lack of patient selection, together with the variety of rehabilitation methods and protocols, often jeopardize the results of this approach, causing difficulty in evaluating outcomes and addressing proper management, and above all, in obtaining scientific evidence for the efficacy of these methods for specific indications. The authors represent different gastroenterological and surgical scientific societies in Italy, and their aim was to identify the indications and agree on treatment protocols for pelvic floor rehabilitation of patients with defecation disorders. This was achieved by means of a modified Delphi method, utilizing a working team (10 members) which developed the statements and a consensus group (15 members, different from the previous ones) which voted twice also suggesting modifications of the statements.


Asunto(s)
Estreñimiento/rehabilitación , Incontinencia Fecal/rehabilitación , Gastroenterología/normas , Guías de Práctica Clínica como Asunto/normas , Sociedades Médicas/normas , Defecación , Técnica Delphi , Humanos , Italia , Diafragma Pélvico
9.
J Thromb Haemost ; 16(10): 2035-2043, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29993188

RESUMEN

Essentials Missense mutations often impair protein folding, and thus intracellular trafficking and secretion. Cellular models of severe type I hemophilia B were challenged with chaperone-like compounds. Sodium phenylbutyrate improved intracellular trafficking and secretion of the frequent p.R294Q. The increased coagulant activity levels (∼3%) of p.R294Q would ameliorate the bleeding phenotype. SUMMARY: Background Missense mutations often impair protein folding and intracellular processing, which can be improved by small compounds with chaperone-like activity. However, little has been done in coagulopathies, where even modest increases of functional levels could have therapeutic implications. Objectives To rescue the expression of factor IX (FIX) variants affected by missense mutations associated with type I hemophilia B (HB) through chaperone-like compounds. Methods Expression studies of recombinant (r)FIX variants and evaluation of secreted levels (ELISA), intracellular trafficking (immunofluorescence) and activity (coagulant assays) before and after treatment of cells with chaperone-like compounds. Results As a model we chose the most frequent HB mutation (p.R294Q, ~100 patients), compared with other recurrent mutations associated with severe/moderate type I HB. Immunofluorescence studies revealed retention of rFIX variants in the endoplasmic reticulum and negligible localization in the Golgi, thus indicating impaired intracellular trafficking. Consistently, and in agreement with coagulation phenotypes in patients, all missense mutations resulted in impaired secretion (< 1% wild-type rFIX). Sodium phenylbutyrate (NaPBA) quantitatively improved trafficking to the Golgi and dose dependently promoted secretion (from 0.3 ± 0.1% to 1.5 ± 0.3%) only of the rFIX-294Q variant. Noticeably, this variant displayed a specific coagulant activity that was higher (~2.0 fold) than that of wild-type rFIX in all treatment conditions. Importantly, coagulant activity was concurrently increased to levels (3.0 ± 0.9%) that, if achieved in patients, would ameliorate the bleeding phenotype. Conclusions Altogether, our data detail molecular mechanisms underlying type I HB and candidate NaPBA as affordable 'personalized' therapeutics for patients affected by the highly frequent p.R294Q mutation, and with reduced access to substitutive therapy.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Factor IX/genética , Factor IX/metabolismo , Hemofilia B/tratamiento farmacológico , Mutación Missense , Fenilbutiratos/farmacología , Relación Dosis-Respuesta a Droga , Células HEK293 , Hemofilia B/sangre , Hemofilia B/genética , Humanos , Transporte de Proteínas , Vías Secretoras
10.
J Prev Med Hyg ; 59(1): E1-E7, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29938233

RESUMEN

The influenza viruses have the ability to agglutinate erythrocytes by binding to sialic acid receptors on the host cell. Human influenza viruses preferentially bind to sialic acid linked to galactose by α 2.6 linkage, while avian influenza viruses preferentially bind to sialic acid linked to Gal by α 2.3 linkage. There is a close correlation between the ability of influenza A viruses to agglutinate erythrocytes from different animal species and their receptor specificity. The haemagglutination and haemagglutination inhibition assays are influenced by the species of erythrocytes. To provide an overview of the expression of sialic acid receptors on different erythrocytes, avian (turkey, chicken, pigeon) and mammalian (sheep, horse, human) species have been analysed by flow cytometry. Chicken, turkey and human erythrocytes display both types of linkages. Horse and sheep erythrocytes show almost exclusively α 2.3 Gal linkages, while pigeon erythrocytes express almost exclusively α 2.6 Gal linkages. The erythrocytes from the same avian and mammalian species have been evaluated by haemagglutination and haemagglutination inhibition assays with seasonal and avian strains. Chicken and turkey erythrocytes seem to be the most appropriate for both assays with seasonal influenza strains, in addition to pigeon erythrocytes, particularly for the B strains. In the case of the avian strain, chicken erythrocytes are suitable for haemagglutination assay and horse erythrocytes for haemagglutination inhibition assay. The choice of erythrocytes has a significant impact on the titres measured by both assays.


Asunto(s)
Eritrocitos/virología , Virus de la Influenza A/metabolismo , Receptores de Superficie Celular/metabolismo , Animales , Aves , Pruebas de Inhibición de Hemaglutinación/métodos , Caballos , Humanos , Gripe Aviar , Gripe Humana , Ovinos
11.
Nat Geosci ; 11: 77-81, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30984285

RESUMEN

After the Moon's formation, Earth experienced a protracted bombardment by leftover planetesimals. The mass delivered during this stage of late accretion has been estimated to be approximately 0.5% of Earth's present mass, based on highly siderophile element concentrations in the Earth's mantle and the assumption that all highly siderophile elements delivered by impacts were retained in the mantle. However, late accretion may have involved mostly large (≥ 1,500 km in diameter)-and therefore differentiated-projectiles in which highly siderophile elements were sequestered primarily in metallic cores. Here we present smoothed-particle hydrodynamics impact simulations that show that substantial portions of a large planetesimal's core may descend to the Earth's core or escape accretion entirely. Both outcomes reduce the delivery of highly siderophile elements to the Earth's mantle and imply a late accretion mass that may be two to five times greater than previously thought. Further, we demonstrate that projectile material can be concentrated within localized domains of Earth's mantle, producing both positive and negative 182W isotopic anomalies of the order of 10 to 100 ppm. In this scenario, some isotopic anomalies observed in terrestrial rocks can be explained as products of collisions after Moon formation.

12.
Geophys Res Lett ; 44(13): 6570-6578, 2017 07 16.
Artículo en Inglés | MEDLINE | ID: mdl-28989206

RESUMEN

Prior to the arrival of the Dawn spacecraft at Ceres, the dwarf planet was anticipated to be ice-rich. Searches for morphological features related to ice have been ongoing during Dawn's mission at Ceres. Here we report the identification of pitted terrains associated with fresh Cerean impact craters. The Cerean pitted terrains exhibit strong morphological similarities to pitted materials previously identified on Mars (where ice is implicated in pit development) and Vesta (where the presence of ice is debated). We employ numerical models to investigate the formation of pitted materials on Ceres and discuss the relative importance of water ice and other volatiles in pit development there. We conclude that water ice likely plays an important role in pit development on Ceres. Similar pitted terrains may be common in the asteroid belt and may be of interest to future missions motivated by both astrobiology and in situ resource utilization.

13.
Tech Coloproctol ; 21(6): 451-459, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28567692

RESUMEN

BACKGROUND: The aim of this study was to determine the effects of a low fermentable oligo-, di- and monosaccharides and polyols (FODMAP) diet on the nutritional status and body composition, abdominal symptoms, quality of life, anxiety/depression and sleep quality of patients with irritable bowel syndrome (IBS). METHODS: Consecutive patients were given a low FODMAP diet for 8 weeks. At baseline and after 8 weeks, blood tests were taken to evaluate nutritional status and a bioelectrical impedance analysis was performed to assess body composition. Anthropometric data, IBS Symptom Severity Score, results of a bowel habits questionnaire, Bristol Stool Chart classification, SF36, Hamilton Depression Anxiety Scale outcome and Pittsburgh Sleep Quality Index were also recorded. During the 8-week diet period, the patients were phoned periodically by the nutritionist to verify their compliance. RESULTS: Twenty-six IBS patients with a mean age of 46.2 ± 13.8 years were studied. After 8 weeks, there were no abnormalities in anthropometric data, bioelectrical impedance parameters and blood tests. The patients' IBS Symptom Severity Score improved (305.2 ± 84.1 vs 156.3 ± 106.4; p < 0.0001), as did bowel habits, Bristol Stool Chart classification, quality of life and HADS anxiety score, whereas sleeping quality and depression were unchanged. The degree of relief from symptoms and satisfaction with the diet was high. CONCLUSIONS: A low FODMAP diet improved IBS symptoms without effects on nutritional status and body composition.


Asunto(s)
Composición Corporal/fisiología , Dieta/métodos , Impedancia Eléctrica , Síndrome del Colon Irritable/dietoterapia , Síndrome del Colon Irritable/fisiopatología , Adolescente , Adulto , Anciano , Disacáridos/efectos adversos , Disacáridos/sangre , Femenino , Fermentación , Humanos , Síndrome del Colon Irritable/sangre , Masculino , Persona de Mediana Edad , Monosacáridos/efectos adversos , Monosacáridos/sangre , Estado Nutricional , Oligosacáridos/efectos adversos , Oligosacáridos/sangre , Proyectos Piloto , Calidad de Vida , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Adulto Joven
14.
J Prev Med Hyg ; 58(1): E27-E33, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28515628

RESUMEN

Herpes simplex viruses (HSV) are among the most widespread causative agents of human viral infections. HSV-2 is one of the commonest causes of genital disease, while HSV-1 is associated primarily with orolabial ulceration; however, recent changes in HSV epidemiology showed an increase in genital and neonatal herpes particularly caused by HSV-1. The main purpose of this study was to assess the seroprevalence of HSV-1 and HSV-2 in a random population in Siena (central Italy) in 2000, 2005 and 2013-2014 and in Bari (southern Italy) in 2005. Moreover, a preliminary study was conducted to investigate the spread of HSV infection in a population of pregnant women and infants in Bari in 2003, 2004 and 2005. Human serum samples were tested for the presence of specific anti-HSV-1 and anti-HSV-2 IgG antibodies using a commercially available ELISA test. For the primary purpose, seroprevalence rates observed in Siena were compared over the years sampled and with the seroprevalence rate found in Bari. Results of seroprevalence in Siena show a decreased trend for both viruses, especially in adolescents and young adults; moreover, HSV-2 seroprevalence rates found in the two cities suggest geographical differences. For the secondary purpose, prevalence rates among pregnant women were compared with the seroprevalence found in women of the general population. No significant difference in prevalence rates were found among pregnant women, while results indicate both viruses are a source of infection in infants.


Asunto(s)
Herpes Simple/epidemiología , Herpes Simple/virología , Herpesvirus Humano 1/inmunología , Herpesvirus Humano 2/inmunología , Adulto , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Lactante , Recién Nacido , Italia/epidemiología , Masculino , Embarazo , Complicaciones Infecciosas del Embarazo/epidemiología , Complicaciones Infecciosas del Embarazo/virología , Prevalencia , Estudios Seroepidemiológicos
15.
Neurogastroenterol Motil ; 29(11)2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28543861

RESUMEN

BACKGROUND: Acid exposure time (AET) is considered the most useful parameter to predict response of reflux-related heartburn to medical or surgical treatment. However, recent studies showed high rates of heartburn response to proton pump inhibitor (PPI) therapy in patients with normal AET. We aimed to compare the efficacy of postreflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) with AET in linking PPI-responsive heartburn to reflux. METHODS: Off-therapy impedance-pH tracings from 425 patients, 317 with PPI-responsive and 108 with PPI-refractory heartburn were blindly re-analyzed. Demographic and endoscopic characteristics, conventional impedance-pH variables, PSPW index, and MNBI were assessed with multivariate logistic regression to identify factors independently associated with PPI responsiveness. Prediction models were developed to assess the strength of reflux linkage with factors independently associated with PPI responsiveness by calculating the area under the curve (AUC) at receiver-operating-characteristic (ROC) analysis. KEY RESULTS: At multivariate logistic regression analysis, AET, MNBI, and PSPW index were the only factors independently associated with PPI responsiveness, abnormal values found in 60%, 76%, and 92% of PPI-responsive cases (P<.017). At ROC analysis, PSPW index (AUC:.794, P=.002) and MNBI (AUC: 0.742, P=.003), both separately and combined (AUC: 0.811, P<.001) linked reflux with PPI-responsiveness better than AET (AUC: 0.687). CONCLUSIONS & INFERENCES: AET, PSPW index, and MNBI are independently associated with PPI-responsive heartburn. PSPW index and MNBI can link PPI-responsive heartburn to reflux better than AET and should become part of the standard analysis of impedance-pH tracings.


Asunto(s)
Reflujo Gastroesofágico/diagnóstico , Reflujo Gastroesofágico/tratamiento farmacológico , Pirosis/diagnóstico , Pirosis/tratamiento farmacológico , Peristaltismo , Inhibidores de la Bomba de Protones/uso terapéutico , Deglución , Impedancia Eléctrica , Monitorización del pH Esofágico , Femenino , Reflujo Gastroesofágico/complicaciones , Pirosis/complicaciones , Humanos , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Resultado del Tratamiento
16.
Science ; 355(6332): 1392-1395, 2017 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-28325842

RESUMEN

The Rosetta spacecraft spent ~2 years orbiting comet 67P/Churyumov-Gerasimenko, most of it at distances that allowed surface characterization and monitoring at submeter scales. From December 2014 to June 2016, numerous localized changes were observed, which we attribute to cometary-specific weathering, erosion, and transient events driven by exposure to sunlight and other processes. While the localized changes suggest compositional or physical heterogeneity, their scale has not resulted in substantial alterations to the comet's landscape. This suggests that most of the major landforms were created early in the comet's current orbital configuration. They may even date from earlier if the comet had a larger volatile inventory, particularly of CO or CO2 ices, or contained amorphous ice, which could have triggered activity at greater distances from the Sun.

17.
Science ; 355(6326): 719-722, 2017 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-28209893

RESUMEN

Organic compounds occur in some chondritic meteorites, and their signatures on solar system bodies have been sought for decades. Spectral signatures of organics have not been unambiguously identified on the surfaces of asteroids, whereas they have been detected on cometary nuclei. Data returned by the Visible and InfraRed Mapping Spectrometer on board the Dawn spacecraft show a clear detection of an organic absorption feature at 3.4 micrometers on dwarf planet Ceres. This signature is characteristic of aliphatic organic matter and is mainly localized on a broad region of ~1000 square kilometers close to the ~50-kilometer Ernutet crater. The combined presence on Ceres of ammonia-bearing hydrated minerals, water ice, carbonates, salts, and organic material indicates a very complex chemical environment, suggesting favorable environments to prebiotic chemistry.

18.
Methods Enzymol ; 588: 171-186, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28237100

RESUMEN

It is widely acknowledged that mitochondria are highly active structures that rapidly respond to cellular and environmental perturbations by changing their shape, number, and distribution. Mitochondrial remodeling is a key component of diverse biological processes, ranging from cell cycle progression to autophagy. In this chapter, we describe different methodologies for the morphological study of the mitochondrial network. Instructions are given for the preparation of samples for fluorescent microscopy, based on genetically encoded strategies or the employment of synthetic fluorescent dyes. We also propose detailed protocols to analyze mitochondrial morphometric parameters from both three-dimensional and bidimensional datasets. Finally, we describe a protocol for the visualization and quantification of mitochondrial structures through electron microscopy.


Asunto(s)
Autofagia , Microscopía Confocal/métodos , Microscopía Electrónica/métodos , Mitocondrias/ultraestructura , Mitofagia , Imagen Óptica/métodos , Animales , Colorantes Fluorescentes/análisis , Proteínas Fluorescentes Verdes/análisis , Humanos , Mitocondrias/metabolismo
19.
Int Rev Cell Mol Biol ; 328: 49-103, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28069137

RESUMEN

Mitochondria, the organelles that function as the powerhouse of the cell, have been increasingly linked to the pathogenesis of many neurological disorders, including multiple sclerosis (MS). MS is a chronic inflammatory demyelinating disease of the central nervous system (CNS) and a leading cause of neurological disability in young adults in the western world. Its etiology remains unknown, and while the inflammatory component of MS has been heavily investigated and targeted for therapeutic intervention, the failure of remyelination and the process of axonal degeneration are still poorly understood. Recent studies suggest a role of mitochondrial dysfunction in the neurodegenerative aspects of MS. This review is focused on mitochondrial functions under physiological conditions and the consequences of mitochondrial alterations in various CNS disorders. Moreover, we summarize recent findings linking mitochondrial dysfunction to MS and discuss novel therapeutic strategies targeting mitochondria-related pathways as well as emerging experimental approaches for modeling mitochondrial disease.


Asunto(s)
Mitocondrias/metabolismo , Esclerosis Múltiple/genética , Animales , Modelos Animales de Enfermedad , Humanos , Modelos Biológicos , Terapia Molecular Dirigida , Esclerosis Múltiple/patología , Esclerosis Múltiple/terapia , Degeneración Nerviosa/patología
20.
Artículo en Inglés | MEDLINE | ID: mdl-27620303

RESUMEN

BACKGROUND: On-therapy impedance-pH monitoring in proton pump inhibitor (PPI)-refractory gastroesophageal reflux disease (GERD) yielded conflicting results. We aimed to assess the diagnostic value of postreflux swallow-induced peristaltic wave (PSPW) index and mean nocturnal baseline impedance (MNBI) in PPI-refractory heartburn. METHODS: On-therapy impedance-pH tracings from 189 consecutive patients with PPI-refractory heartburn were blindly reviewed. Patients were subdivided into refractory reflux esophagitis (RRE), healed reflux esophagitis (HRE), non-erosive reflux disease (NERD), and functional heartburn (FH) according to endoscopic and conventional impedance-pH findings. The diagnostic accuracy of PSPW index and MNBI in separating NERD from FH was assessed with receiver-operating-characteristic (ROC) analysis. Objectively documented persistent reflux remission at 3-year follow-up in 53 patients who underwent laparoscopic fundoplication served to evaluate PSPW index and MNBI as independent predictors of PPI-refractory GERD confirmed by positive surgical outcome. KEY RESULTS: Median PSPW index and MNBI values were significantly lower in 39 RRE (16%; 1145 Ω) than in 41 HRE (25%; 1741 Ω) and in 68 NERD (29%; 2374 Ω) patients, and in all three GERD subgroups compared to 41 FH cases (67%; 3488 Ω) (P<.008). At ROC analysis, comparing NERD to FH the area under the curve was 0.886 with PSPW index and 0.677 with MNBI (P=.005). PSPW index was an independent predictor of PPI-refractory GERD (odds ratio 0.6983, P=.012). CONCLUSIONS & INFERENCES: At on-therapy impedance-pH monitoring, PSPW index and MNBI efficiently distinguish PPI-refractory NERD from FH. The PSPW index represents an independent predictor of PPI-refractory GERD.


Asunto(s)
Deglución/fisiología , Impedancia Eléctrica , Monitorización del pH Esofágico/métodos , Reflujo Gastroesofágico/fisiopatología , Pirosis/fisiopatología , Peristaltismo/fisiología , Adulto , Femenino , Reflujo Gastroesofágico/diagnóstico , Pirosis/diagnóstico , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
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