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1.
Phys Chem Chem Phys ; 26(12): 9197-9206, 2024 Mar 20.
Artículo en Inglés | MEDLINE | ID: mdl-38376884

RESUMEN

The electron induced dissociation of condensed benzene (C6H6) in thin films deposited on a Pt substrate is investigated by electron stimulated desorption (ESD) of anions and cations. The desorbed yields are recorded as a function of incident electron energy in the range of 10 to 950 eV for a fixed film thickness of 2 monolayers (ML) and for a fixed energy of 950 eV, as well as a function of film thickness from 0.5 to 8 monolayers (ML) for anions, and from 0.5 to 12ML for cations. Both energy and thickness dependencies are discussed in terms of the three main mechanisms yielding positively and/or negatively charged fragments: dissociative electron attachment (DEA), dipolar dissociation (DD) and dissociative ionization (DI) processes. At the probed energies, DD is the major mechanism, while DEA is predominantly induced by secondary electrons from the Pt substrate. Desorption of the parent positive ion is strongly suppressed. Similar qualitative behaviours are observed for the energy dependence of both anion and cation ESD yields, while some discrepancies exist in the thickness dependence, including a very significant systematic magnitude difference found between such ions formation. An estimation of the effective DD cross-section including the desorption probability is obtained. Feasible mechanisms behind the observed energy and thickness dependences for anion and cation yields are proposed. These results highlight the need for further investigations to better understand the underlying processes of electron induced dissociation in condensed matter.

2.
Public Health ; 230: 12-20, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38479163

RESUMEN

OBJECTIVE: This article aims to estimate the differences in environmental impact (greenhouse gas [GHG] emissions, land use, energy used, acidification and potential eutrophication) after one year of promoting a Mediterranean diet (MD). METHODS: Baseline and 1-year follow-up data from 5800 participants in the PREDIMED-Plus study were used. Each participant's food intake was estimated using validated semi-quantitative food frequency questionnaires, and the adherence to MD using the Dietary Score. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The influence of diet on environmental impact was assessed through the EAT-Lancet Commission tables. The association between MD adherence and its environmental impact was calculated using adjusted multivariate linear regression models. RESULTS: After one year of intervention, the kcal/day consumed was significantly reduced (-125,1 kcal/day), adherence to a MD pattern was improved (+0,9) and the environmental impact due to the diet was significantly reduced (GHG: -361 g/CO2-eq; Acidification:-11,5 g SO2-eq; Eutrophication:-4,7 g PO4-eq; Energy use:-842,7 kJ; and Land use:-2,2 m2). Higher adherence to MD (high vs. low) was significantly associated with lower environmental impact both at baseline and one year follow-up. Meat products had the greatest environmental impact in all the factors analysed, both at baseline and at one-year follow-up, in spite of the reduction observed in their consumption. CONCLUSIONS: A program promoting a MD, after one year of intervention, significantly reduced the environmental impact in all the factors analysed. Meat products had the greatest environmental impact in all the dimensions analysed.


Asunto(s)
Dieta Mediterránea , Gases de Efecto Invernadero , Humanos , Dieta , Ambiente , Recolección de Datos
3.
Artículo en Inglés | MEDLINE | ID: mdl-38376473

RESUMEN

Summary: Background. Patch testing (PT) is used to identify substances that cause allergic contact dermatitis (ACD). However, the clinical effects of allergen restrictions following PT have not been thoroughly investigated. This study aims to assess the diagnostic accuracy of PT in patients suspected of having ACD. Methods. Prospective study. PT were performed in patients with clinical diagnosis of ACD. Patients with a positive PT (case group) had a strict restriction of the suspected substance for one month. In patients with negative patch testing (control group), allergen restriction was based in clinical history. Clinical reduction (CR) of at least 50% in disease activity (CR50%) after one month of allergen restriction was considered clinically relevant. Total control was defined as clinical reduction of at least 90% (CR90%). Results. From 400 patients, 66.2% had a positive PT. The sensitivity of PT to identify CR50% was 84%, specificity 47%, PPV 53%, and NPV 81%. Only 10.5% of patients achieved CR90%. Conclusions. The PT had moderate diagnostic accuracy. It could be useful as a screening, but a positive result should be confirmed with controlled allergen restriction. The low number of patients who achieved a 90% CR invites to reconsider the allergens included in PT and the mechanistic processes of the disease.

4.
Phys Chem Chem Phys ; 25(30): 20510-20518, 2023 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-37470102

RESUMEN

In this study, a complete and self-consistent cross section dataset for electron transport simulations through gaseous benzene in the energy range 0.1-1000 eV has been critically compiled. Its reliability has been evaluated through a joint experimental and computational procedure. To accomplish this, the compiled dataset has been used as input for event-by-event Monte Carlo simulations of the magnetically confined electron transport through gaseous benzene, and the simulated transmitted intensity has been compared with the experimental one for different incident energies and benzene gas pressures.

5.
J Endocrinol Invest ; 46(3): 567-576, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36242744

RESUMEN

OBJECTIVE: Human brown adipose tissue (BAT) has gained considerable attention as a potential therapeutic target for obesity and its related cardiometabolic diseases; however, whether the gut microbiota might be an efficient stimulus to activate BAT metabolism remains to be ascertained. We aimed to investigate the association of fecal microbiota composition with BAT volume and activity and mean radiodensity in young adults. METHODS: 82 young adults (58 women, 21.8 ± 2.2 years old) participated in this cross-sectional study. DNA was extracted from fecal samples and 16S rRNA sequencing was performed to analyse the fecal microbiota composition. BAT was determined via a static 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography-computed tomography scan (PET/CT) after a 2 h personalized cooling protocol. 18F-FDG uptake was also quantified in white adipose tissue (WAT) and skeletal muscles. RESULTS: The relative abundance of Akkermansia, Lachnospiraceae sp. and Ruminococcus genera was negatively correlated with BAT volume, BAT SUVmean and BAT SUVpeak (all rho ≤ - 0.232, P ≤ 0.027), whereas the relative abundance of Bifidobacterium genus was positively correlated with BAT SUVmean and BAT SUVpeak (all rho ≥ 0.262, P ≤ 0.012). On the other hand, the relative abundance of Sutterellaceae and Bifidobacteriaceae families was positively correlated with 18F-FDG uptake by WAT and skeletal muscles (all rho ≥ 0.213, P ≤ 0.042). All the analyses were adjusted for the PET/CT scan date as a proxy of seasonality. CONCLUSION: Our results suggest that fecal microbiota composition is involved in the regulation of BAT and glucose uptake by other tissues in young adults. Further studies are needed to confirm these findings. CLINICAL TRIAL INFORMATION: ClinicalTrials.gov no. NCT02365129 (registered 18 February 2015).


Asunto(s)
Microbiota , Tomografía Computarizada por Tomografía de Emisión de Positrones , Adulto , Femenino , Humanos , Adulto Joven , Tejido Adiposo Pardo/diagnóstico por imagen , Tejido Adiposo Pardo/metabolismo , Estudios Transversales , Fluorodesoxiglucosa F18 , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , ARN Ribosómico 16S/genética
6.
Pediatr Res ; 92(3): 838-847, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34845351

RESUMEN

BACKGROUND: Preterm infants are generally fed through nasogastric enteral feeding tubes (NEFTs). The aim of this work was to evaluate the role of NEFTs in the initial colonization of the preterm gut and its evolution within the first 2 weeks after birth. METHODS: For this purpose, fecal and NEFT-derived samples from 30 preterm infants hospitalized in a neonatal intensive care unit (NICU) were collected from birth to the second week of life. Samples were cultivated in ten culture media, including three for the isolation of antibiotic-resistant microorganisms. RESULTS: Isolates (561) were identified by 16S ribosomal RNA gene sequencing. Although the first NEFTs inserted into the neonates after birth were rarely colonized, analysis of NEFTs and fecal samples over time revealed a significant increase in bacterial abundance, diversity, and detection frequency. Results showed a parallel colonization between time-matched NEFTs and fecal samples, suggesting an ongoing bidirectional transfer of bacteria from the neonatal gut to the NEFTs and vice versa. CONCLUSIONS: In short-term hospitalization, length is by far the determinant factor for the early colonization of preterm infants. As NEFT populations reflect the bacterial populations that are colonizing the preterm in a precise moment, their knowledge could be useful to prevent the dissemination of antibiotic-resistant strains. IMPACT: The hospital environment modulates preterm colonization immediately after birth. The colonization of preterm feces and NEFTs occurs in parallel. There is an ongoing bidirectional transfer of microorganisms from the neonatal gut to the NEFTs and vice versa. Bacterial communities inside NEFTs could act as reservoirs of antibiotic resistance genes. NEFT populations reflect the bacteria that are colonizing the preterm at a precise moment.


Asunto(s)
Nutrición Enteral , Recien Nacido Prematuro , Antibacterianos , Bacterias , Medios de Cultivo , Heces/microbiología , Humanos , Lactante , Recién Nacido , Unidades de Cuidado Intensivo Neonatal , Intubación Gastrointestinal
7.
Rev Med Chil ; 150(10): 1310-1316, 2022 Oct.
Artículo en Español | MEDLINE | ID: mdl-37358089

RESUMEN

BACKGROUND: The treatment of Crohn's disease (CD) is based on medical therapy and surgery is reserved for failure of medical management or complications. AIM: To evaluate endoscopic, clinical, and surgical recurrence of CD after surgery. MATERIAL AND METHODS: In a prospectively maintained database, consecutive patients older than 15 years subjected to an ileocecal resection for ileocolic disease from January 2011 to April 2021, were identified. The diagnosis of CD was confirmed with the pathologic report. Patients with less than one year of follow-up were excluded. Information was obtained retrospectively from the database and clinical records. RESULTS: Fourteen patients were identified. The mean age at the time of surgery was 38 years. Surgery was performed at a median of 41.5 months (0-300) after the diagnosis of CD, nine elective and five emergency procedures. In five patients there were four major and two minor postoperative complications, with no anastomotic leakage. Six patients had endoscopic recurrence and seven had clinical recurrence (50%) at a mean of 15 months, one of whom required a second operation. There was no mortality. CONCLUSIONS: After the surgical treatment of CD, the clinical and endoscopic recurrence rate continues to be high.


Asunto(s)
Enfermedad de Crohn , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven , Ciego/cirugía , Enfermedad de Crohn/diagnóstico , Enfermedad de Crohn/cirugía , Endoscopía , Íleon/cirugía , Complicaciones Posoperatorias/epidemiología , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento
8.
Med Oral Patol Oral Cir Bucal ; 27(1): e25-e34, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34874926

RESUMEN

BACKGROUND: to analyse the potential risk factors of tongue lesions, comparing the results with a control group. MATERIAL AND METHODS: An observational, case-control study was designed. The study included a case group comprising 336 patients with tongue lesions and 336 sex and age-matched controls. We recorded tobacco/alcohol habits, presence of dentures, allergies, medical conditions, and medications. Statistical analysis was performed via logistic regression models to estimate the odds ratio (OR) adjusted for gender, age, tobacco, and alcohol using propensity score-matching analysis (PSM). RESULTS: According to the final PSM model, patients with tongue lesions were more likely to suffer from allergies (OR 2.13; 1.27-3.66) or medical conditions (OR 2.14; 1.19-3.85), and more likely to take medication (OR 1.99; 1.11-3.57). Elderly individuals were more prone to hairy tongue (OR 3.82; 1.53-10.47). Smoking was associated with coated tongue (OR 2.05; 1.12-3.63), hairy tongue (OR 3.77; 1.52-9.22) and median rhomboid glossitis (OR 40.49; 5.84-860.43). Allergic individuals were more likely to exhibit sublingual varices (OR 1.73; 1.02-2.88). Medical conditions increased the chances of having coated tongue (OR 2.44; 1.36-4.64) or crenated tongue (OR 2.70; 1.42-5.30). Arterial hypertension was associated with median rhomboid glossitis (OR 5.85; 1.08-34.18). Individuals on medication showed a higher risk of fissured tongue (OR 1.87; 1.20-2.94) and varices (OR 2.42; 1.58-3.80). Agents acting on the alimentary tract and metabolism increased the probability of fissured tongue (OR 2.31; 1.42-3.79). CONCLUSIONS: As far as we are aware, this is the first study on lingual pathology to include a PSM analysis. The results suggest that a history of allergies, the presence of medical conditions, and the use of medication are associated with increased probability of tongue lesions. The analysis of diseases and medications by subgroups requires studies matched by habits with larger sample sizes, in order to corroborate our observations.


Asunto(s)
Enfermedades de la Lengua , Lengua Fisurada , Anciano , Estudios de Casos y Controles , Humanos , Puntaje de Propensión , Factores de Riesgo , Lengua
9.
Antimicrob Agents Chemother ; 65(9): e0043221, 2021 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-34152813

RESUMEN

Soil-transmitted-helminth (STH) infections are a persistent global public health problem. Control strategies for STH have been based on the use of mass drug administration (MDA) mainly targeting preschool- and school-aged-children, although there is increasing interest in expanding treatment to include adults and others through community-wide MDA. Coverage assessment is critical to understanding the real effectiveness of albendazole (ALB) treatment in those MDA programs. The work described here aims to (i) evaluate the effect of type of diet (a heavy or light meal) and fasting before ALB treatment on the systemic disposition of ALB and its metabolites in treated human volunteers and (ii) evaluate the potential feasibility of detecting albendazole metabolites in urine. The data reported here demonstrate that the systemic availability of the active ALB-sulfoxide (ALBSO) metabolite was enhanced more than 2-fold after food ingestion (a heavy or light meal). ALB dissolution improvement related to the ingestion of food may modify the amount of drug/metabolites reaching the parasite, affecting drug efficacy and the overall success of MDA strategies. The measurement in urine samples of the amino-ALB-sulfone (NHALBSO2) derivative and ALBSO for up to 96 h suggests that it may be feasible to develop a noninvasive tool to evaluate compliance/adherence to ALB treatment.


Asunto(s)
Antihelmínticos , Helmintiasis , Absorción Fisiológica , Adulto , Albendazol/uso terapéutico , Antihelmínticos/uso terapéutico , Niño , Preescolar , Voluntarios Sanos , Helmintiasis/tratamiento farmacológico , Humanos , Administración Masiva de Medicamentos , Suelo
10.
Eur Phys J E Soft Matter ; 44(7): 87, 2021 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-34196906

RESUMEN

 The eukaryotic flagellum propels sperm cells and simultaneously detects physical and chemical cues that modulate the waveform of the flagellar beat. Most previous studies have characterized the flagellar beat and swimming trajectories in two space dimensions (2D) at a water/glass interface. Here, using refined holographic imaging methods, we report high-quality recordings of three-dimensional (3D) flagellar bending waves. As predicted by theory, we observed that an asymmetric and planar flagellar beat results in a circular swimming path, whereas a symmetric and non-planar flagellar beat results in a twisted-ribbon swimming path. During swimming in 3D, human sperm flagella exhibit torsion waves characterized by maxima at the low curvature regions of the flagellar wave. We suggest that these torsion waves are common in nature and that they are an intrinsic property of beating axonemes. We discuss how 3D beat patterns result in twisted-ribbon swimming paths. This study provides new insight into the axoneme dynamics, the 3D flagellar beat, and the resulting swimming behavior.


Asunto(s)
Flagelos , Natación , Humanos , Masculino , Espermatozoides
11.
Phys Chem Chem Phys ; 22(24): 13505-13515, 2020 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-32530024

RESUMEN

Absolute total electron scattering cross sections (TCS) for nitrobenzene molecules with impact energies from 0.4 to 1000 eV have been measured by means of two different electron-transmission experimental arrangements. For the lower energies (0.4-250 eV) a magnetically confined electron beam system has been used, while for energies above 100 eV a linear beam transmission technique with high angular resolution allowed accurate measurements up to 1000 eV impact energy. In both cases random uncertainties were maintained below 5-8%. Systematic errors arising from the angular and energy resolution limits of each apparatus are analysed in detail and quantified with the help of our theoretical calculations. Differential elastic and integral elastic, excitation and ionisation as well as momentum transfer cross sections have been calculated, for the whole energy range considered here, by using an independent atom model in combination with the screening corrected additivity rule method including interference effects (IAM-SCARI). Due to the significant permanent dipole moment of nitrobenzene, additional differential and integral rotational excitation cross sections have been calculated in the framework of the Born approximation. If we ignore the rotational excitations, our calculated total cross section agrees well with our experimental results for impact energies above 15 eV. Additionally, they overlap at 10 eV with the low energy Schwinger Multichannel method with Pseudo Potentials (SMCPP) calculation available in the literature (L. S. Maioli and M. H. F. Bettega, J. Chem. Phys., 2017, 147, 164305). We find a broad feature in the experimental TCS at around 1.0 eV, which has been related to the formation of the NO2- anion and assigned to the π*(b1) resonance, according to previous mass spectra available in the literature. Other local maxima in the TCSs are found at 4.0 ± 0.2 and 5.0 ± 0.2 eV and are assigned to core excited resonances leading to the formation of the NO2- and O2- anions, respectively. Finally, for energies below 10 eV, differences found between the present measurements, the SMCPP calculation and our previous data for non-polar benzene have revealed the importance of accurately calculating the rotational excitation contribution to the TCS before comparing theoretical and experimental data. This comparison suggests that our dipole-Born calculation for nitrobenzene overestimates the magnitude of the rotational excitation cross sections below 10 eV.

12.
N Z Vet J ; 68(3): 187-192, 2020 May.
Artículo en Inglés | MEDLINE | ID: mdl-31778612

RESUMEN

ABSTRACTAims: The main goal of the current study was to evaluate, on a commercial beef cattle farm, the impact of infection with gastrointestinal nematodes resistant to both ivermectin (IVM) and moxidectin (MXD) on the productivity of calves.Methods: Male Aberdeen Angus calves, aged 9-11 months, with faecal nematode egg counts (FEC) ≥200 epg and body weight ≥190 kg, were allocated to two herds. Herd A (n = 90) grazed a maize-winter forage crop rotation and Herd B (n = 90) grazed a 2-year-old Agropyrum pasture. On Day 0 in each herd, calves were randomly allocated into five groups (n = 18), which were treated with 0.2 mg/kg IVM; 0.2 mg/kg MXD; 3.75 mg/kg ricobendazole (RBZ), both IVM and RBZ, or remained untreated. Faecal samples collected on Days -1 and 19 were used to determine the percentage reduction in FEC, and genera of the nematodes were determined by the identification of the third-stage larvae recovered from faecal cultures. Total weight gain was determined from body weights recorded on Days -1 and 91.Results: Overall mean reduction in FEC was 42% for IVM, 67% for MXD, 97% for RBZ and 99% for IVM + RBZ. The reduction in FEC for Cooperia spp. was ≤78% for IVM and MXD, and for Haemonchus spp. was 0 and 36% for IVM and MXD, respectively, confirming the presence of parasites resistant to both anthelmintics. Only IVM + RBZ treatment resulted in 100% efficacy against Haemonchus spp. The overall estimated mean total weight gain for calves treated with IVM was 15.7 (95% CI = 11.9-19.7) kg and for calves treated with IVM + RBZ was 28.8 (95% CI = 25-32.5) kg (p < 0.001). Mean total weight gain for calves treated with MXD was 23.5 (95% CI = 19.7-27.2) kg.Conclusions and clinical relevance: In calves naturally infected with resistant nematodes, under the production system assessed here, weight gains were lower in calves treated with anthelmintics that were moderately or highly ineffective compared to those treated with highly effective anthelmintics. These results demonstrate to farmers and veterinarians the importance of a sustainable and effective nematode control under field conditions.


Asunto(s)
Albendazol/análogos & derivados , Antiparasitarios/farmacología , Enfermedades de los Bovinos/tratamiento farmacológico , Ivermectina/farmacología , Macrólidos/farmacología , Infecciones por Nematodos/veterinaria , Albendazol/farmacología , Animales , Antihelmínticos/farmacología , Antinematodos/farmacología , Argentina , Peso Corporal/efectos de los fármacos , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/fisiopatología , Resistencia a Múltiples Medicamentos , Quimioterapia Combinada/veterinaria , Masculino , Infecciones por Nematodos/tratamiento farmacológico , Infecciones por Nematodos/fisiopatología , Recuento de Huevos de Parásitos/veterinaria , Carne Roja
13.
Expert Rev Proteomics ; 16(7): 583-591, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-31195841

RESUMEN

Introduction: Hypertension is a multifactorial disease that has, thus far, proven to be a difficult target for pharmacological intervention. The application of proteomic strategies may help to identify new biomarkers for the early diagnosis and prompt treatment of hypertension, in order to control blood pressure and prevent organ damage. Areas covered: Advances in proteomics have led to the discovery of new biomarkers to help track the pathophysiological processes implicated in hypertension. These findings not only help to better understand the nature of the disease, but will also contribute to the clinical needs for a timely diagnosis and more precise treatment. In this review, we provide an overview of new biomarkers identified in hypertension through the application of proteomic techniques, and we also discuss the difficulties and challenges in identifying biomarkers in this clinical setting. We performed a literature search in PubMed with the key words 'hypertension' and 'proteomics', and focused specifically on the most recent literature on the utility of proteomics in hypertension research. Expert opinion: There have been several promising biomarkers of hypertension identified by proteomics, but too few have been introduced to the clinic. Thus, further investigations in larger cohorts are necessary to test the feasibility of this strategy for patients. Also, this emerging field would profit from more collaboration between clinicians and researchers.


Asunto(s)
Biomarcadores/metabolismo , Hipertensión/metabolismo , Proteómica/métodos , Humanos , Medicina de Precisión/métodos
14.
Cardiovasc Drugs Ther ; 33(4): 415-424, 2019 08.
Artículo en Inglés | MEDLINE | ID: mdl-31209632

RESUMEN

PURPOSE: Recent advances in genomics offer a smart option for predicting future risk of disease and prognosis. The objective of this study was to examine the prognostic value in heart failure (HF) patients, of a series of single nucleotide polymorphisms (SNPs). METHODS: A selection of 192 SNPs found to be related with obesity, body mass index, circulating lipids or cardiovascular diseases were genotyped in 191 patients with HF. Anthropometrical and clinical variables were collected for each patient, and death and readmission by HF were registered as the primary endpoint. RESULTS: A total of 53 events were registered during a follow-up period of 438 (263-1077) days (median (IQR)). Eight SNPs strongly related to obesity and HF prognosis were selected as possible prognostic variables. From these, rs10189761 and rs737337 variants were independently associated with HF prognosis (HR 2.295 (1.287-4.089, 95% CI); p = 0.005), whereas rs10423928, rs1800437, rs737337 and rs9351814 were related with bad prognosis only in obese patients (HR 2.142 (1.438-3.192, 95% CI); p = 0.00018). Combined scores of the genomic variants were highly predictive of poor prognosis. CONCLUSIONS: SNPs rs10189761 and rs737337 were identified, for the first time, as independent predictors of major clinical outcomes in patients with HF. The data suggests an additive predictive value of these SNPs for a HF prognosis. In particular for obese patients, SNPs rs10423928, rs1800437, rs737337 and rs9351814 were related with a bad prognosis. Combined scores weighting the risk of each genomic variant could effect interesting new tools to stratify the prognostic risk of HF patients.


Asunto(s)
Insuficiencia Cardíaca/genética , Obesidad/genética , Polimorfismo de Nucleótido Simple , Anciano , Anciano de 80 o más Años , Biomarcadores/sangre , Índice de Masa Corporal , Progresión de la Enfermedad , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Insuficiencia Cardíaca/mortalidad , Insuficiencia Cardíaca/fisiopatología , Humanos , Lípidos/sangre , Masculino , Persona de Mediana Edad , Obesidad/mortalidad , Obesidad/fisiopatología , Fenotipo , Pronóstico , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
15.
J Chem Phys ; 151(8): 084310, 2019 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-31470731

RESUMEN

Measurements of the total electron scattering cross sections (TCSs) from benzene, in the impact energy range of 1-1000 eV, are presented here by combining two different experimental systems. The first utilizes a magnetically confined electron transmission beam for the lower energies (1-300 eV), while the second utilizes a linear transmission beam apparatus for the higher energies (100-1000 eV). These cross sections have also been calculated by means of two different theoretical methods, the Schwinger Multichannel with Pseudo Potential (SMCPP) procedure, employing two different approaches to account for the polarization of the target for impact energies between 0.1 and 15 eV, and the Independent Atom Model with the Screening Corrected Additivity Rule including Interference effect (IAM-SCAR+I) paradigm to cover the 10-10 000 eV impact energy range. The present results are compared with available theoretical and experimental data, with the level of accord being good in some cases and less satisfactory in others, and some predicted resonances have been identified. In particular, we found a π* shape resonance at 1.4 eV and another feature in the energy region 4.6-4.9 eV interpreted as a π* resonance (2B2g symmetry), which is a mixture of shape and a core excited resonance, as well as a Feshbach resonance at 5.87 eV associated with the 3s (a1g) Rydberg state. A Born-type formula to extrapolate TCS values for energies above 10 000 eV is also given. This study provides a complete set of TCS data, with uncertainty limits within 10%, ready to be used for modeling electron transport applications.

16.
Zygote ; 27(6): 398-404, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-31576792

RESUMEN

Quality of in vitro-produced embryos is influenced by changes in gene expression in response to adverse conditions. Gene markers for predicting 'good embryos' do not exist at present. We propose that the expression of pluripotency markers OCT4-SOX2-NANOG in D9 (day 9) bovine demi-embryos correlated with development at D13 (day 13). Day 8 in vitro-produced blastocysts were split in two cloned halves, one half (D9) was subjected to analysis of pluripotency markers and the other was kept in culture until D13 of development. Embryo development was scored and correlated with its own status at D9 and assigned to one of two categories: G1, arrested/dead; or G2, development up to D13. SOX2 and NANOG expression levels were significantly higher in embryos from G1 and there was also negative correlation between SOX2 and embryo survival to D13 (G3; r = -0.37; P = 0.03). We observed a significant reduction in the expression of the three studied genes from D9 to D13. Furthermore, there was a correlation between the expression of pluripotency markers at D9 and embryo diameter and the expression of trophoblastic markers at D13 (TP1-EOMES-FGF4-CDX2-TKDP1). Finally, the quotient between the relative expression of SOX2 and OCT4 in the D9 blastocysts from G1 and G2 showed that embryos that were considered as competent (G2) had a quotient close to one, while the other group had a quotient of 2.3 due to a higher expression of SOX2. These results might indicate that overexpression of SOX2 at the blastocyst stage had a negative effect on the control of embryonic developmental potential.


Asunto(s)
Blastocisto/metabolismo , Técnicas de Cultivo de Embriones/métodos , Embrión de Mamíferos/metabolismo , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica , Factores de Transcripción SOXB1/genética , Animales , Blastocisto/citología , Bovinos , Embrión de Mamíferos/citología , Embrión de Mamíferos/embriología , Femenino , Factores de Tiempo
17.
J Clin Pediatr Dent ; 43(3): 185-189, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30964726

RESUMEN

Aim: To determine prevalence, severity, and risk factors associated with Molar Incisor Hypomineralization (MIH) in schoolchildren between 6 and 15 years of age in Medellin, Colombia. Study design: We conducted a retrospective observational study including 1.075 children born and residing in Medellin, Colombia. A structured questionnaire addressing gestational period and first three years of child's life was administered to biological mothers. Two calibrated examiners established MIH diagnosis following the European Academy of Paediatric Dentistry criteria. Data were analyzed using descriptive statistics, bivariate analysis, and linear regression with a 5% significance. Results: Study population was predominantly male (70.7%), average age was 9.3±1.9 years. Prevalence of MIH was 11,2%. The majority of defects (85%) were mild. MIH was associated with alterations during last gestational trimester, type of childbirth and respiratory problems. Conclusion. MIH prevalence in schoolchildren between 6 and 15 years of age was 11.2%, being mild defects more frequently found. MIH was associated with different factors during pregnancy and the first three years of life.


Asunto(s)
Hipoplasia del Esmalte Dental , Complicaciones del Embarazo , Enfermedades Respiratorias , Adolescente , Niño , Colombia , Hipoplasia del Esmalte Dental/complicaciones , Hipoplasia del Esmalte Dental/epidemiología , Femenino , Humanos , Incisivo , Masculino , Diente Molar , Embarazo , Complicaciones del Embarazo/epidemiología , Prevalencia , Enfermedades Respiratorias/complicaciones , Enfermedades Respiratorias/epidemiología , Estudios Retrospectivos , Factores de Riesgo
20.
J Chem Phys ; 149(24): 244304, 2018 Dec 28.
Artículo en Inglés | MEDLINE | ID: mdl-30599735

RESUMEN

Using our magnetically confined electron transmission apparatus, we report the results of total cross sections (TCSs) for electron scattering from dichloromethane (CH2Cl2). The energy range of this study is 1-300 eV. Wherever possible, the present data are compared to earlier measured TCSs of Wan et al. [J. Chem. Phys. 94, 1865 (1991)] and Karwasz et al. [Phys. Rev. A 59, 1341 (1999)] and to the corresponding theoretical independent atom model with screening corrected additivity rule and interference term (IAM-SCAR+I) results of Krupa et al. [Phys. Rev. A 97, 042702 (2018)] and a spherical complex optical potential formulation calculation of Naghma et al. [J. Electron Spectrosc. Relat. Phenom. 193, 48 (2014)]. Within their respective uncertainties, the present TCS and those of Karwasz et al. are found to be in very good agreement over their common energy range. However, agreement with the results of Wan et al. is quite poor. The importance of the experimentally inherent 'missing angle' effect (see later) on the measured TCS is investigated and found to be significant at the lower energies studied. Indeed, when this effect is accounted for, agreement between our measured TCSs and the corrected IAM-SCAR+I+rotations calculation results are, for energies above about 3 eV, in good accord (to better than 8%). Finally, we observe two σ * shape resonances, consistent with the earlier electron transmission spectroscopy results of Burrow et al. [J. Chem. Phys. 77, 2699 (1982)], at about 2.8 eV and 4.4 eV incident electron energy, in our measured TCS.

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