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1.
Nature ; 594(7863): 365-368, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34135524

RESUMEN

Red supergiants are the most common final evolutionary stage of stars that have initial masses between 8 and 35 times that of the Sun1. During this stage, which lasts roughly 100,000 years1, red supergiants experience substantial mass loss. However, the mechanism for this mass loss is unknown2. Mass loss may affect the evolutionary path, collapse and future supernova light curve3 of a red supergiant, and its ultimate fate as either a neutron star or a black hole4. From November 2019 to March 2020, Betelgeuse-the second-closest red supergiant to Earth (roughly 220 parsecs, or 724 light years, away)5,6-experienced a historic dimming of its visible brightness. Usually having an apparent magnitude between 0.1 and 1.0, its visual brightness decreased to 1.614 ± 0.008 magnitudes around 7-13 February 20207-an event referred to as Betelgeuse's Great Dimming. Here we report high-angular-resolution observations showing that the southern hemisphere of Betelgeuse was ten times darker than usual in the visible spectrum during its Great Dimming. Observations and modelling support a scenario in which a dust clump formed recently in the vicinity of the star, owing to a local temperature decrease in a cool patch that appeared on the photosphere. The directly imaged brightness variations of Betelgeuse evolved on a timescale of weeks. Our findings suggest that a component of mass loss from red supergiants8 is inhomogeneous, linked to a very contrasted and rapidly changing photosphere.

2.
Int J Legal Med ; 135(5): 1675-1684, 2021 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34216266

RESUMEN

The Y chromosome has been widely explored for the study of human migrations. Due to its paternal inheritance, the Y chromosome polymorphisms are helpful tools for understanding the geographical distribution of populations all over the world and for inferring their origin, which is really useful in forensics. The remarkable historical context of Europe, with numerous migrations and invasions, has turned this continent into a melting pot. For this reason, it is interesting to study the Y chromosome variability and how it has contributed to improving our knowledge of the distribution and development of European male genetic pool as it is today. The analysis of Y lineages in Europe shows the predominance of four haplogroups, R1b-M269, I1-M253, I2-M438 and R1a-M420. However, other haplogroups have been identified which, although less frequent, provide significant evidence about the paternal origin of the populations. In addition, the study of the Y chromosome in Europe is a valuable tool for revealing the genetic trace of the different European colonizations, mainly in several American countries, where the European ancestry is mostly detected by the presence of the R1b-M269 haplogroup. Therefore, the objective of this review is to compile the studies of the Y chromosome haplogroups in current European populations, in order to provide an outline of these haplogroups which facilitate their use in forensic studies.


Asunto(s)
Cromosomas Humanos Y/genética , Variación Genética , Haplotipos , Población Blanca/genética , Europa (Continente)/etnología , Migración Humana , Humanos , Repeticiones de Microsatélite , Filogenia , Filogeografía , Polimorfismo de Nucleótido Simple
3.
Epidemiol Infect ; 149: e76, 2021 03 15.
Artículo en Inglés | MEDLINE | ID: mdl-33715660

RESUMEN

Rabies is endemic in Bangladesh. To identify risk factors, a case-control study was conducted based on hospital-reported rabid animal bite (RAB) cases in domestic ruminants, 2009 - 2018. RAB cases (n = 449) and three controls per case were selected. Dogs (87.8%) and jackals (12.2%) were most often identified as biting animals. In the final multivariable model, the risk of being a RAB case was significantly higher in cattle aged >0.5-2 years (odds ratio (OR) 2.89; 95% confidence interval (CI): 1.56-5.37), >2-5 years (OR 3.63; 95% CI: 1.97-6.67) and >5 years (OR 6.42; 95% CI: 3.39-12.17) compared to those aged <0.5 years. Crossbred cattle were at higher risk of being a RAB case (OR 5.48; 95% CI: 3.56-8.42) than indigenous. Similarly, female cattle were more likely to be a RAB case (OR 1.26; 95% CI: 1.15-2.29) than males. Cattle in rural areas (OR 39.48; 95% CI: 6.14-254.00) were at a much higher risk of being RAB cases than those in urban areas. Female, crossbred and older cattle, especially in rural areas should either be managed indoors during the dog breeding season (September and October) or vaccinated. A national rabies elimination program should prioritise rural dogs for mass vaccination. Jackals should also be immunised using oral bait vaccines. Prevention of rabies in rural dogs and jackals would also reduce rabies incidence in humans.


Asunto(s)
Bangladesh , Mordeduras y Picaduras/veterinaria , Enfermedades de los Bovinos/virología , Enfermedades de los Perros/virología , Rabia/veterinaria , Animales , Bangladesh/epidemiología , Bovinos , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Perros/epidemiología , Perros , Humanos , Rabia/epidemiología , Rabia/transmisión , Estudios Retrospectivos , Factores de Riesgo , Zoonosis
4.
Med Mycol ; 2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32944758

RESUMEN

Given the predisposition of South American camelids to coccidioidomycosis, we sought to describe the disease presentation in alpacas and llamas and identify potential risk factors for these species. The records of 224 llamas and alpacas that were tested for Coccidioides infection using immunodiffusion serology at the Coccidioidomycosis Serology Laboratory of the University of California, Davis, between 1990 and 2016 were examined; of those, 46 alpacas and 42 llamas had positive test results. The remaining 99 alpacas and 37 llamas were used as control groups. We found that male llamas were at increased risk for Coccidioides infection when compared with female llamas and when compared with male alpacas. South American camelids living within California were at higher risk for infection than camelids living in other states. Alpacas were more likely than llamas to have subclinical infections. We documented five cases of abortion or neonatal mortality attributable to coccidioidomycosis in alpacas. Our study demonstrates that South American camelids are susceptible to Coccidioides infection in areas where the disease is endemic, lending support to the importance of vigilance for this disease in alpacas and llamas and suggesting a possible role for these animals as sentinel species. LAY SUMMARY: We examined cases of Valley Fever and described the disease and risk factors for llamas and alpacas. Male llamas were at increased risk for infection as were animals living within California. Five alpacas had miscarriages or neonatal deaths as a result of Valley Fever infections.

5.
J Phys Chem A ; 124(41): 8359-8372, 2020 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-32886505

RESUMEN

This work presents an in-depth discussion on the nonequilibrium dissociation of O2 molecules colliding with O atoms, combining quasi-classical trajectory calculations, master equation, and dimensionality reduction. A rovibrationally resolved database for all of the elementary collisional processes is constructed by including all nine adiabatic electronic states of O3 in the QCT calculations. A detailed analysis of the ab initio data set reveals that for a rovibrational level, the probability of dissociating is mostly dictated by its deficit in internal energy compared to the centrifugal barrier. Because of the assumption of rotational equilibrium, the conventional vibrational-specific calculations fail to characterize such a dependence. Based on this observation, a new physics-based grouping strategy for application to coarse-grained models is proposed. By relying on a hybrid technique made of rovibrationally resolved excitation coupled to coarse-grained dissociation, the new approach is compared to the vibrational-specific model and the direct solution of the rovibrational state-to-state master equation. Simulations are performed in a zero-dimensional isothermal and isochoric chemical reactor for a wide range of temperatures (1500-20,000 K). The study shows that the main contribution to the model inadequacy of vibrational-specific approaches originates from the incapability of characterizing dissociation, rather than the energy transfers. Even when constructed with only twenty groups, the new reduced-order model outperforms the vibrational-specific one in predicting all of the QoIs related to dissociation kinetics. At the highest temperature, the accuracy in the mole fraction is improved by 2000%.

6.
Med Teach ; 42(9): 1051-1057, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32697116

RESUMEN

BACKGROUND: Medical curricula have historically been designed in a top-down approach, usually excluding students. While Delphi panels have been used as a tool for medical education curricula design, none have been conducted in Ecuador. In addition, no such approach has ever included students both as panelists and researchers. MATERIAL AND METHODS: Four Delphi panels were developed and conducted using a participatory approach that allowed medical students to take part both as expert panelists and researchers: specifically, students developed the questionnaire and conducted a qualitative synthesis. Questionnaire responses were anonymized and dispatched online to panelists. The information was organized and collected to develop the qualitative syntheses and prepare the final statements. RESULTS: Thirty-two medical students participated between February and May 2018. A total of 32 questions were developed, corresponding to five different categories. For some questions, consensus was reached; for other questions, general statements were obtained.Discussion and conclusion: Developing the questionnaire, responding to it and analyzing the answers allowed students to raise significant concerns regarding medical education topics proposing relevant policy and curricula change. Participatory Delphi panels can be an efficient tool to obtain organized feedback, improve student class involvement, and promote research skills.


Asunto(s)
Educación de Pregrado en Medicina , Educación Médica , Estudiantes de Medicina , Curriculum , Técnica Delphi , Ecuador , Humanos
7.
Clin Exp Dermatol ; 43(4): 423-429, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29460336

RESUMEN

BACKGROUND: The choice of prescribed emollients is usually based on cost and patient preference. Differences in formulations can affect user acceptability. AIM: To compare the physical performance, user acceptability and various product design features of two emollient gels that are prescribed in the UK and alleged to be therapeutically interchangeable because their formulations are described as having the same contents of oily ingredients. RESULTS: We found that here are in fact significant measurable differences between the structure and performance of the two formulations, which materially affect their user acceptability. These differences are attributed to the use of different types of gelling agents and other ingredients of differing grades/quality and concentrations, and probably due to the formulations being made by different manufacturing processes. We also identified other product design features that are important to user appeal, including the type of container in which the formulations are presented, the type of dispensing devices provided, and the nature and form of the supplied user instructions. CONCLUSION: Patients and prescribers should be aware that there can be important differences in performance and user appeal between emollients, even between products that, superficially, may appear to be very similar. These important performance aspects should be characterized for new emollient introductions to encourage better informed product selection.


Asunto(s)
Emolientes , Adolescente , Adulto , Comportamiento del Consumidor , Emolientes/química , Emolientes/uso terapéutico , Femenino , Geles/química , Geles/uso terapéutico , Humanos , Masculino , Embalaje de Productos , Adulto Joven
8.
J Dairy Sci ; 101(7): 6388-6398, 2018 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-29605315

RESUMEN

Consumption of an adequate volume of high-quality colostrum is vital to a dairy calf's ability to survive and become a productive herd member. However, some dairy herds have reported a deficiency of colostrum production, which ranges from a low volume to no colostrum produced, by cows during fall and winter. Little information regarding this phenomenon exists. The purpose of this study was to characterize the syndrome and identify potential risk factors for low colostrum yield. A 2,500-cow Jersey dairy farm was enrolled in a prospective cohort study in May 2016, to evaluate possible effects of photoperiod, temperature, and cow factors on colostrum production. Dairy personnel were trained to collect, weigh, and evaluate colostrum quality. Information on parity, previous lactation length, previous 305-d mature-equivalent milk production, and dry period length were collected through the farm's dairy management software. Weather and photoperiod data were also collected. Over the year of enrollment, 2,988 eligible cows calved and had colostrum weights recorded and 38% were primiparous (n = 1,143), 25% were in their second lactation (n = 752), and 37% were in their third or greater lactation (n = 1,093). The overall average colostrum yield was 6.6 kg/cow in June 2016, 2.5 kg/cow in December 2016, and 4.8 kg/cow in May 2017. Multiparous cows had a larger decline in colostrum production between June and December (6.6 to 1.3 kg/cow) compared with primiparous animals (6.5 to 4.2 kg/cow). Overall, average colostrum production decreased by 0.17 kg/cow per week during this time, 0.22 kg for multiparous cows and 0.08 kg for primiparous cows. A logistic regression model was constructed for all cows to evaluate effects of cow factors on low colostrum production (<2.7 kg at first milking). Dry period length, calf sex, singleton or twin, age at freshening, month of calving and previous lactation length were significantly associated with the probability of low colostrum yield (<2.7 kg at first milking). A cross-correlation function analysis between the time series for colostrum yield and photoperiod revealed a high correlation at the time of calving and 1 mo prior, particularly for multiparous cows. A pedigree analysis showed that extreme colostrum yield (low vs. high) followed some sire lines. Low colostrum production in this herd could have an economic effect on the dairy and calf health and appears to have a strong seasonal and, potentially, a genetic component.


Asunto(s)
Bovinos , Calostro/metabolismo , Leche/química , Paridad , Animales , Femenino , Lactancia , Embarazo , Estudios Prospectivos , Factores de Riesgo , Estaciones del Año
9.
Int J Biometeorol ; 62(9): 1721-1732, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29948412

RESUMEN

Pollen allergies have a remarkable clinical impact all over world. Quercus pollen is the main allergen in many parts of world. Due to the health impacts caused by exposure to oak pollen, the objectives of this study are to characterise the aerobiological behaviour of Quercus pollen and to determine its potential sources as well as their transport through the atmosphere of Mexico City and surrounding areas between January 2012 and June 2015. Airborne Quercus pollen monitoring was carried out simultaneously in five zones of Mexico City. The percentage of Quercus pollen of the total pollen collected from the air showed that the highest concentration was recorded in 2014, followed by 2012. The annual seasonal variation indicated that flowering and pollen emission into the atmosphere began between February and March. The maximum concentration of Quercus pollen was reached at Cuajimalpa. In 2012, the amount of pollen grains was distributed in March and April uniformly, whilst in 2014, the largest amount of pollen was concentrated in March. In 2012 and 2014 (years with the highest pollen concentrations), corresponding intraday variations were quite similar, with a low relative maximum in the morning and the highest concentrations in the evening. The largest values were recorded in 2014, and two processes can explain these. In the afternoon, pollen from secondary forest is carried by southwesterly converging winds, increasing the pollen concentration in Cuajimalpa. In the evening, there is an additional pollen contribution from primary forest via transport by NW winds.


Asunto(s)
Monitoreo del Ambiente , Polen , Quercus , Alérgenos , Atmósfera , Ciudades , México , Estaciones del Año
11.
Am J Transplant ; 17(4): 1071-1080, 2017 04.
Artículo en Inglés | MEDLINE | ID: mdl-27639262

RESUMEN

After extensive experimentation, outcomes of a first clinical normothermic machine perfusion (NMP) liver trial in the United Kingdom demonstrated feasibility and clear safety, with improved liver function compared with standard static cold storage (SCS). We present a preliminary single-center North American experience using identical NMP technology. Ten donor liver grafts were procured, four (40%) from donation after circulatory death (DCD), of which nine were transplanted. One liver did not proceed because of a technical failure with portal cannulation and was discarded. Transplanted NMP grafts were matched 1:3 with transplanted SCS livers. Median NMP was 11.5 h (range 3.3-22.5 h) with one DCD liver perfused for 22.5 h. All transplanted livers functioned, and serum transaminases, bilirubin, international normalized ratio, and lactate levels corrected in NMP recipients similarly to controls. Graft survival at 30 days (primary outcome) was not statistically different between groups on an intent-to-treat basis (p = 0.25). Intensive care and hospital stays were significantly more prolonged in the NMP group. This preliminary experience demonstrates feasibility as well as potential technical risks of NMP in a North American setting and highlights a need for larger, randomized studies.


Asunto(s)
Trasplante de Hígado , Preservación de Órganos/métodos , Perfusión/métodos , Complicaciones Posoperatorias , Isquemia Tibia , Adolescente , Adulto , Anciano , Circulación Extracorporea , Femenino , Supervivencia de Injerto , Humanos , Pruebas de Función Hepática , Masculino , Persona de Mediana Edad , Donantes de Tejidos , Adulto Joven
12.
Clin Exp Immunol ; 187(1): 160-173, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27681197

RESUMEN

We have reported previously that T cells from patients with multi-drug-resistant tuberculosis (MDR-TB) express high levels of interleukin (IL)-17 in response to the MDR strain M (Haarlem family) of Mycobacterium tuberculosis (M. tuberculosis). Herein, we explore the pathways involved in the induction of Th17 cells in MDR-TB patients and healthy tuberculin reactors [purified protein derivative healthy donors (PPD+ HD)] by the M strain and the laboratory strain H37Rv. Our results show that IL-1ß and IL-6 are crucial for the H37Rv and M-induced expansion of IL-17+ interferon (IFN)-γ- and IL-17+ IFN-γ+ in CD4+ T cells from MDR-TB and PPD+ HD. IL-23 plays an ambiguous role in T helper type 1 (Th1) and Th17 profiles: alone, IL-23 is responsible for M. tuberculosis-induced IL-17 and IFN-γ expression in CD4+ T cells from PPD+ HD whereas, together with transforming growth factor (TGF-ß), it promotes IL-17+ IFN-γ- expansion in MDR-TB. In fact, spontaneous and M. tuberculosis-induced TGF-ß secretion is increased in cells from MDR-TB, the M strain being the highest inducer. Interestingly, Toll-like receptor (TLR)-2 signalling mediates the expansion of IL-17+ IFN-γ- cells and the enhancement of latency-associated protein (LAP) expression in CD14+ and CD4+ T cells from MDR-TB, which suggests that the M strain promotes IL-17+ IFN-γ- T cells through a strong TLR-2-dependent TGF-ß production by antigen-presenting cells and CD4+ T cells. Finally, CD4+ T cells from MDR-TB patients infected with MDR Haarlem strains show higher IL-17+ IFN-γ- and lower IL-17+ IFN-γ+ levels than LAM-infected patients. The present findings deepen our understanding of the role of IL-17 in MDR-TB and highlight the influence of the genetic background of the infecting M. tuberculosis strain on the ex-vivo Th17 response.


Asunto(s)
Memoria Inmunológica , Interleucina-17/metabolismo , Interleucina-23/metabolismo , Mycobacterium tuberculosis/inmunología , Células Th17/inmunología , Factor de Crecimiento Transformador beta/metabolismo , Tuberculosis Resistente a Múltiples Medicamentos/inmunología , Tuberculosis Pulmonar/inmunología , Adulto , Células Cultivadas , Farmacorresistencia Bacteriana Múltiple , Femenino , Humanos , Interferón gamma/metabolismo , Masculino , Persona de Mediana Edad , Mycobacterium tuberculosis/genética , Transducción de Señal , Especificidad de la Especie , Células Th17/microbiología , Receptor Toll-Like 2/metabolismo , Tuberculosis Resistente a Múltiples Medicamentos/genética , Tuberculosis Pulmonar/microbiología , Adulto Joven
13.
J Anat ; 231(5): 776-784, 2017 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-28791699

RESUMEN

Co-localization of dopamine with other classical neurotransmitters in the same neuron is a common phenomenon in the brain of vertebrates. In mammals, some dopaminergic neurons of the ventral tegmental area and the hypothalamus have a glutamatergic co-phenotype. However, information on the presence of this type of dopaminergic neurons in other vertebrate groups is very scant. Here, we aimed to provide new insights on the evolution of this neuronal co-phenotype by studying the presence of a dual dopaminergic/glutamatergic neuron phenotype in the central nervous system of lampreys. Double immunofluorescence experiments for dopamine and glutamate in adult sea lampreys revealed co-localization of both neurotransmitters in some neurons of the preoptic nucleus, the nucleus of the postoptic commissure, the dorsal hypothalamus and in cerebrospinal fluid-contacting cells of the caudal rhombencephalon and rostral spinal cord. Moreover, co-localization of dopamine and glutamate was found in dopaminergic fibres in a few brain regions including the lateral pallium, striatum, and the preoptic and postoptic areas but not in the brainstem. Our results suggest that the presence of neurons with a dopaminergic/glutamatergic co-phenotype is a primitive character shared by jawless and jawed vertebrates. However, important differences in the distribution of these neurons and fibres were noted among the few vertebrates investigated to date. This study offers an anatomical basis for further work on the role of glutamate in dopaminergic neurons.


Asunto(s)
Encéfalo/citología , Encéfalo/metabolismo , Neuronas Dopaminérgicas/metabolismo , Ácido Glutámico/metabolismo , Animales , Neuronas Dopaminérgicas/citología , Lampreas
14.
Br J Dermatol ; 176(6): 1633-1644, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28192600

RESUMEN

BACKGROUND: The quality of systematic reviews and meta-analyses on psoriasis, a chronic inflammatory skin disease that severely impairs quality of life and is associated with high costs, remains unknown. OBJECTIVES: To assess the methodological quality of systematic reviews published on psoriasis. METHODS: After a comprehensive search in MEDLINE, Embase and the Cochrane Database (PROSPERO: CDR42016041611), the quality of studies was assessed by two raters using the Assessment of Multiple Systematic Reviews (AMSTAR) tool. Article metadata and journal-related bibliometric indices were also obtained. Systematic reviews were classified as low (0-4), moderate (5-8) or high (9-11) quality. A prediction model for methodological quality was fitted using principal component and multivariate ordinal logistic regression analyses. RESULTS: We classified 220 studies as high (17·2%), moderate (55·0%) or low (27·8%) quality. Lower compliance rates were found for AMSTAR question (Q)5 (list of studies provided, 11·4%), Q10 (publication bias assessed, 27·7%), Q4 (status of publication included, 39·5%) and Q1 (a priori design provided, 40·9%). Factors such as meta-analysis inclusion [odds ratio (OR) 6·22; 95% confidence interval (CI) 2·78-14·86], funding by academic institutions (OR 2·90, 95% CI 1·11-7·89), Article Influence score (OR 2·14, 95% CI 1·05-6·67), 5-year impact factor (OR 1·34, 95% CI 1·02-1·40) and article page count (OR 1·08, 95% CI 1·02-1·15) significantly predicted higher quality. A high number of authors with a conflict of interest (OR 0·90, 95% CI 0·82-0·99) was significantly associated with lower quality. CONCLUSIONS: The methodological quality of systematic reviews published about psoriasis remains suboptimal. The type of funding sources and author conflicts may compromise study quality, increasing the risk of bias.


Asunto(s)
Metaanálisis como Asunto , Psoriasis , Literatura de Revisión como Asunto , Autoria , Conflicto de Intereses , Dermatología/estadística & datos numéricos , Ética en Investigación , Humanos , Factor de Impacto de la Revista , Publicaciones Periódicas como Asunto/ética , Publicaciones Periódicas como Asunto/normas , Sesgo de Publicación , Apoyo a la Investigación como Asunto
15.
Epidemiol Infect ; 145(4): 802-817, 2017 03.
Artículo en Inglés | MEDLINE | ID: mdl-27938416

RESUMEN

Animal health surveillance enables the detection and control of animal diseases including zoonoses. Under the EU-FP7 project RISKSUR, a survey was conducted in 11 EU Member States and Switzerland to describe active surveillance components in 2011 managed by the public or private sector and identify gaps and opportunities. Information was collected about hazard, target population, geographical focus, legal obligation, management, surveillance design, risk-based sampling, and multi-hazard surveillance. Two countries were excluded due to incompleteness of data. Most of the 664 components targeted cattle (26·7%), pigs (17·5%) or poultry (16·0%). The most common surveillance objectives were demonstrating freedom from disease (43·8%) and case detection (26·8%). Over half of components applied risk-based sampling (57·1%), but mainly focused on a single population stratum (targeted risk-based) rather than differentiating between risk levels of different strata (stratified risk-based). About a third of components were multi-hazard (37·3%). Both risk-based sampling and multi-hazard surveillance were used more frequently in privately funded components. The study identified several gaps (e.g. lack of systematic documentation, inconsistent application of terminology) and opportunities (e.g. stratified risk-based sampling). The greater flexibility provided by the new EU Animal Health Law means that systematic evaluation of surveillance alternatives will be required to optimize cost-effectiveness.


Asunto(s)
Enfermedades de los Animales/epidemiología , Monitoreo Epidemiológico/veterinaria , Animales , Bovinos , Unión Europea , Aves de Corral , Encuestas y Cuestionarios , Porcinos , Suiza
16.
J Appl Microbiol ; 122(4): 911-920, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28066967

RESUMEN

AIMS: This study investigates the antimicrobial activity in Staphylococcus aureus isolates (methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA)) and antioxidant activity of green propolis, Baccharis dracunculifolia DC extracts and Artepillin C™. METHODS AND RESULTS: The amount of Artepillin C in different extracts was determined by high performance liquid chromatography analysis. Minimum inhibitory concentration 90 (MIC90) was determined using 40 isolates of S. aureus inoculated in Müeller-Hinton agar culture medium containing the green propolis and B. dracunculifolia DC extracts. PVEE (green propolis ethanolic extract) and BDEH (B. dracunculifolia hexanic extract) showed the greatest antimicrobial activity with MIC90 values of 246·3 and 295·5 µg ml-1 respectively. Green propolis ethanolic and hexanic extracts (PVEE and PVEH respectively) showed the greatest antioxidant activity assessed by DPPH (1,1-diphenyl-2-picryl hydrazyl radical) with IC50 values of 13·09 and 95·86 µg ml-1 respectively. CONCLUSIONS: Green propolis ethanolic displays better antimicrobial and antioxidant activities compared to other extracts. These activities may be related to the presence of Artepillin C in synergism with the other constituents of the extracts. SIGNIFICANCE AND IMPACT OF THE STUDY: In this study, the antimicrobial activity of the extracts of green propolis and B. dracunculifolia DC demonstrated in MRSA and MSSA clinical isolates indicated that they can be important tools to treat infections caused by these bacteria.


Asunto(s)
Antibacterianos/farmacología , Antioxidantes/farmacología , Baccharis/química , Fenoles/farmacología , Fenilpropionatos/farmacología , Própolis/farmacología , Antibacterianos/análisis , Antioxidantes/análisis , Fenilpropionatos/análisis , Extractos Vegetales/química , Extractos Vegetales/farmacología , Própolis/química , Staphylococcus aureus/efectos de los fármacos
17.
J Chem Phys ; 147(5): 054107, 2017 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-28789554

RESUMEN

A novel reduced-order method is presented for modeling reacting flows characterized by strong non-equilibrium of the internal energy level distribution of chemical species in the gas. The approach seeks for a reduced-order representation of the distribution function by grouping individual energy states into macroscopic bins, and then reconstructing state population using the maximum entropy principle. This work introduces an adaptive grouping methodology to identify and lump together groups of states that are likely to equilibrate faster with respect to each other. To this aim, two algorithms have been considered: the modified island algorithm and the spectral clustering method. Both methods require a measure of dissimilarity between internal energy states. This is achieved by defining "metrics" based on the strength of the elementary rate coefficients included in the state-specific kinetic mechanism. Penalty terms are used to avoid grouping together states characterized by distinctively different energies. The two methods are used to investigate excitation and dissociation of N2 (Σg+1) molecules due to interaction with N(Su4) atoms in an ideal chemical reactor. The results are compared with a direct numerical simulation of the state-specific kinetics obtained by solving the master equations for the complete set of energy levels. It is found that adaptive grouping techniques outperform the more conventional uniform energy grouping algorithm by providing a more accurate description of the distribution function, mole fraction and energy profiles during non-equilibrium relaxation.

18.
Bull Entomol Res ; 107(3): 410-418, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28316286

RESUMEN

Cosmopolitan pests such as Brevicoryne brassicae, Lipaphis pseudobrassicae, and Myzus persicae (Aphididae) cause significant damage to Brassicaceae crops. Assessment of the important biotic and abiotic factors that regulate these pests is an essential step in the development of effective Integrated Pest Management programs for these aphids. This study evaluated the influence of leaf position, precipitation, temperature, and parasitism on populations of L. pseudobrassicae, M. persicae, and B. brassicae in collard greens fields in the Triângulo Mineiro region (Minas Gerais state), Brazil. Similar numbers of B. brassicae were found on all parts of the collard green plants, whereas M. persicae and L. pseudobrassicae were found in greatest numbers on the middle and lower parts of the plant. While temperature and precipitation were positively related to aphid population size, their effects were not accumulative, as indicated by a negative interaction term. Although Diaeretiella rapae was the main parasitoid of these aphids, hyperparasitism was dominant; the main hyperparasitoid species recovered from plant samples was Alloxysta fuscicornis. Parasitoids seem to have similar distributions on plants as their hosts. These results may help predict aphid outbreaks and gives clues for specific intra-plant locations when searching for and monitoring aphid populations.


Asunto(s)
Áfidos/fisiología , Brassicaceae/crecimiento & desarrollo , Himenópteros/fisiología , Animales , Áfidos/parasitología , Brasil , Interacciones Huésped-Parásitos , Hojas de la Planta/crecimiento & desarrollo , Lluvia , Temperatura
19.
J Intellect Disabil Res ; 61(12): 1140-1150, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-29154486

RESUMEN

BACKGROUND: This study investigated sensory processing in a sample of Spanish children with autism spectrum disorder (ASD). Specifically, the study aimed to explore (1) the prevalence and distribution of atypical sensory processing patterns, (2) the relationship between adaptive and maladaptive behaviour with atypical sensory processing and (3) the possible relationship between sensory subtype and maternal stress. METHODS: The short sensory profile 2 (Dunn 2014) and the vineland adaptive behavior scale (Sparrow et al. 1984) were administered to examine the sensory processing difficulties and maladaptive behaviours of 45 children with ASD aged 3 to 14; their mothers also completed the parenting stress index-short form (Abidin 1995). RESULTS: Atypical sensory features were found in 86.7% of the children; avoider and sensor being the two most common patterns. No significant relationship was found between atypical sensory processing and adaptive behaviour. However, the analysis showed a strong relationship between sensory processing and maladaptive behaviour. Both maladaptive behaviour and sensory processing difficulties correlated significantly with maternal stress although maternal stress was predicted only by the sensory variable, and in particular by the avoider pattern. CONCLUSIONS: The findings suggest that sensory features in ASD may be driving the high prevalence of parental stress in carers. They also suggest that the effect on parental stress that has been attributed traditionally to maladaptive behaviours may be driven by sensory difficulties. The implications of these findings are discussed in relation to the development of interventions and the need to explore contextual and cultural variables as possible sources of variability.


Asunto(s)
Trastorno del Espectro Autista/fisiopatología , Madres/psicología , Responsabilidad Parental/psicología , Problema de Conducta , Trastornos de la Sensación/fisiopatología , Estrés Psicológico/psicología , Adolescente , Adulto , Trastorno del Espectro Autista/complicaciones , Niño , Preescolar , Femenino , Humanos , Masculino , Trastornos de la Sensación/etiología , España
20.
Actas Dermosifiliogr ; 108(5): 445-456, 2017 Jun.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28267955

RESUMEN

BACKGROUND: The induction of antinuclear antibodies (ANA) and the onset of autoimmune diseases have been reported after treatment with tumor necrosis factor (TNF) inhibitors, though controversy persists. OBJECTIVES: To determine the frequency of onset of autoimmune diseases and of the appearance of autoantibodies in psoriasis patients administered TNF inhibitors (adalimumab and etanercept) subcutaneously and to correlate this with the effectiveness of treatment, adverse effects, and the order of use of TNF inhibitors. We also tried to identify any factors that might predict the appearance of ANA and autimmune diseases. METHODS: We performed a retrospective study of a cohort of 121 patients monitored over an 11-year period. ANA were measured at baseline and at 3, 6, and 12 months; positive results were followed up by study of antibodies to double-stranded DNA. Extractable nuclear antigen (ENA) antibodies were also studied at baseline and at 3, 6, and 12 months. Patients with a baseline assay of ANA and ENA at least one more assay during the first year were included in the study, and these antibodies were measured annually thereafter. Psoriasis area severity index was calculated and adverse effects were recorded at each visit. RESULTS: A significant increase in ANA positivity was observed during treatment of moderate-to-severe psoriasis with adalimumab and etanercept, but this was not associated with the onset of autoimmune diseases. No correlation was observed with treatment efficacy, the order of use of TNF inhibitors, or the appearance of adverse effects. No predictive factors for the appearance of ANA were identified, except for the body mass index. CONCLUSIONS: We recommend ANA measurement and screening for autoimmune diseases prior to treatment with TNF inhibitors, but not routine serial measurements of ANA during follow-up except in patients with signs or symptoms suggestive of autoimmune disease.


Asunto(s)
Adalimumab/efectos adversos , Anticuerpos Antinucleares/biosíntesis , Antirreumáticos/efectos adversos , Enfermedades Autoinmunes/inducido químicamente , Etanercept/efectos adversos , Psoriasis/tratamiento farmacológico , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores , Adalimumab/uso terapéutico , Adolescente , Adulto , Anciano , Anticuerpos Antinucleares/sangre , Antígenos Nucleares/inmunología , Antirreumáticos/uso terapéutico , Autoantígenos/inmunología , Enfermedades Autoinmunes/sangre , Enfermedades Autoinmunes/tratamiento farmacológico , ADN/inmunología , Etanercept/uso terapéutico , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
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