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1.
J Gambl Stud ; 2024 Jun 24.
Artículo en Inglés | MEDLINE | ID: mdl-38913214

RESUMEN

The proliferation of betting shops in Spanish cities is causing a heated social debate in response to the undesirable impacts that businesses of this kind can have. As a result, associations and social movements have emerged to try to stem their expansion and, at the same time, regulations have been introduced to prevent the uncontrolled opening of this type of premises. The limitations set out in the legislation include minimum distances between betting shops and schools. In order to understand the spatial dimension of this phenomenon and to find out the extent to which these businesses comply with the regulations in force, in this paper, we study the distribution of betting shops in the city of Madrid and their proximity to each other and to schools. The results reveal certain areas of the city with a high density of betting shops and with schools with high exposure to these businesses. Likewise, results show the significant number of businesses that would have to close (81%; n = 416) if the current moratorium on betting shops that opened their doors before the current legislation came into force did not exist.

2.
Neuroophthalmology ; 48(4): 294-298, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38933747

RESUMEN

Millard-Gubler syndrome is a pontine syndrome caused by a lesion in the lower pons region. It is characterised by ipsilateral facial paralysis and VI paresis and contralateral brachiocrural palsy. We present the case of a female patient, G4P2A1, at 21 weeks of gestation, with preeclampsia, complaints of blurred vision, diplopia, and right hemiparesis, in whom a clinical diagnosis of Millard-Gubler syndrome was made. Neuroimaging showed an intraparenchymal haemorrhage towards the central portion of the bulbopontine junction. An extensive aetiological study was carried out to determine the cause of the hypertensive disorder syndrome during pregnancy. The patient improved satisfactorily from the neurological deficit after delivery of an early stillbirth.

3.
Int J Cancer ; 152(7): 1314-1319, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36541784

RESUMEN

Cancer is one of the most burdening global health challenges. Indigenous communities are at high risk for worse healthcare outcomes because of inequalities in the incidence, prevalence, and mortality of oncological diseases, that arise from socioeconomic, racial, cultural, religious beliefs, and ethnic factors. Their perception about themselves is closely related to what affects their territory, making them possess a profound rooted feeling with their surroundings, and intense spiritual believes. Consequently, the disease process is linked to physical and emotional imbalances and alterations in their territory. Researchers from the United States, Canada, New Zealand, and Australia have worked diligently to learn about barriers to cancer management among these populations. Unfortunately, robust cancer data is lacking for most of the world's Indigenous, leading to obstacles in information systems and consequently, inequities in healthcare with the perpetuation of the problem. Therefore, a better understanding of cancer as a global health problem is required. Our study aims to propose a holistic and culturally adapted framework to improve cancer health services and outcomes among Indigenous peoples in Colombia.


Asunto(s)
Atención a la Salud , Neoplasias , Humanos , Canadá/epidemiología , Colombia/epidemiología , Neoplasias/epidemiología , Neoplasias/terapia , Estados Unidos , Pueblos Sudamericanos
4.
J Urban Health ; 100(3): 627-637, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37351726

RESUMEN

Measuring the density of alcohol outlets around schools is a critical step towards understanding the drivers of drinking among adolescents. Different methodologies have been used in the literature for this purpose, but the implications of using one methodology or another have not been clearly assessed. Our aim was to compare different methods to measure alcohol outlet density and highlight under which characteristics of the environment might be best using each approach. We used Geographic Information Systems to geolocate schools (n = 576) and alcohol outlets (n = 21,732) in Madrid. We defined the density of alcohol outlets as the number of establishments within an area of 400 m around schools measured using two buffering methods: crow flies' and street network distances. We evaluated the agreement between both methods visually and through regression models, including street connectivity, population density, and density of recreational venues as predictors of disagreement. The density of alcohol outlets around schools was higher using crow flies' distances compared to street network distances. The differences between methodologies were wider in areas of higher density of outlets, especially in the downtown areas, where there are higher population density and street connectivity. Our results suggest that the spatial characteristics and morphology of the study area (e.g., street connectivity and population density) should be considered when deciding the methodology to be used to measure alcohol outlet density. Future studies should explore the implications of different exposure measures in their association with drinking prevalence and consumption patterns among different geographical contexts.


Asunto(s)
Bebidas Alcohólicas , Comercio , Humanos , Sistemas de Información Geográfica , Consumo de Bebidas Alcohólicas/epidemiología , Características de la Residencia , Instituciones Académicas
5.
Med Confl Surviv ; 39(2): 132-149, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37137735

RESUMEN

The objective of the study is to assess the middle-term effects (1 year after intervention) of two community-based mental health interventions, Common Elements Treatment Approach intervention, CETA, and Narrative Community Group Therapy intervention, NCGT, in two cities of the Colombian Pacific region (Buenaventura and Quibdó). A follow-up study was conducted on a cohort of trial participants. In this trial, the positive effects of two mental health interventions were evaluated; assessment was carried out in separate groups (CETA arm, NCGT arm and a control group) of the reduction of symptoms of anxiety, depression, post-traumatic stress and function impaired mentality. The participants were Afro-Colombian survivors of the armed conflict and displacement living in Buenaventura and Quibdó. They were surveyed using the same instrument used in the original trial. Intent-to-treat analyses were performed, and longitudinal mixed-effects regression models with random effects were used to analyse the middle-term effects of the interventions. At 1-year post-intervention, participants in Buenaventura who received the CETA intervention experienced a decrease in depression (-0.23; p = 0.02), post-traumatic stress symptoms (-0.23; p = 0.02) and total mental health symptoms (-0.14; p = 0.048). In Quibdó, the NCGT intervention significantly improved function impairment (-0.30; p = 0.005). CETA and NCGT interventions have the potential to maintain a reduction of mental health symptoms in participants from the Colombian Pacific region.


Asunto(s)
Brazo , Salud Mental , Humanos , Colombia/epidemiología , Estudios de Seguimiento , Sobrevivientes/psicología , Conflictos Armados/psicología
6.
Med Confl Surviv ; 39(1): 28-47, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-36815261

RESUMEN

This study aims to evaluate the effect of a mental health Narrative Community-Based Group Therapy (NCGT) in Afro-Colombian violence survivors. A randomized controlled trial was conducted in Buenaventura and Quibdó, Colombia. Afro-Colombian adults (n=521) were randomly allocated to a NCGT (n1=175), a wait-control group (n2=171) or a Common Elements Treatment Approach (CETA, n3=175). The CETA was described separately given conceptual/methodological differences. Lay psychosocial community workers delivered the NCGT. Symptoms were assessed before and after intervention/wait with culturally adapted mental health symptoms and gender-specific functionality scales. Intent to treat analysis and mean difference of differences were used for comparisons. In Buenaventura, a significant reduction in functional impairment (mean difference: -0.30, 95% Confidence Interval [95% CI]: -0.55, -0.05) and depression (mean difference: -0.24, 95% CI: -0.42, -0.07) were found, with small and moderate effect size, respectively. In Quibdó, functionality improved significantly (mean difference: -0.29, 95% CI: -0.54, -0.04, small effect size). Even though differences in depression and anxiety were not significant, there were reductions in symptoms. The NCGT is effective in improving daily functioning among violence victims in the Colombian Pacific and has the potential to reduce symptoms of depression. Further exploration is required to understand the effects of a narrative group therapy for mental health in Afro-Colombian populations.Trial Registration: ClinicalTrials.gov number: NCT01856673 (https://clinicaltrials.gov/ct2/show/NCT01856673).


Asunto(s)
Trastornos Mentales , Psicoterapia de Grupo , Adulto , Humanos , Colombia , Salud Mental , Violencia/psicología , Trastornos Mentales/terapia
7.
Microb Ecol ; 84(2): 510-526, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-34553243

RESUMEN

Bouvardia ternifolia is a medicinal plant considered a source of therapeutic compounds, like the antitumoral cyclohexapeptide bouvardin. It is known that large number of secondary metabolites produced by plants results from the interaction of the host and adjacent or embedded microorganisms. Using high-throughput DNA sequencing of V3-16S and V5-18S ribosomal gene libraries, we characterized the endophytic, endophytic + epiphyte bacterial, and fungal communities associated to flowers, leaves, stems, and roots, as well as the rhizosphere. The Proteobacteria (average 80.7%) and Actinobacteria (average 14.7%) were the most abundant bacterial phyla, while Leotiomycetes (average 54.8%) and Dothideomycetes (average 27.4%) were the most abundant fungal classes. Differential abundance for the bacterial endophyte group showed a predominance of Erwinia, Propionibacterium, and Microbacterium genera, while Sclerotinia, Coccomyces, and Calycina genera predominated for fungi. The predictive metagenome analysis for bacteria showed significative abundance of pathways for secondary metabolite production, while a FUNguild analysis revealed the presence of pathotroph, symbiotroph, and saprotrophs in the fungal community. Intra and inter copresence and mutual exclusion interactions were identified for bacterial and fungal kingdoms in the endophyte communities. This work provides a description of the diversity and composition of bacterial and fungal microorganisms living in flowers, leaves, stems, roots, and the rhizosphere of this medicinal plant; thus, it paves the way towards an integral understanding in the production of therapeutic metabolites.


Asunto(s)
Micobioma , Plantas Medicinales , Rubiaceae , Bacterias/genética , Endófitos , Hongos/genética , Raíces de Plantas/microbiología , Plantas Medicinales/microbiología , ARN Ribosómico 16S/genética , Rizosfera , Rubiaceae/genética , Microbiología del Suelo
8.
Phys Chem Chem Phys ; 24(19): 11967-11978, 2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35527718

RESUMEN

Phytochromes, found in plants, fungi, and bacteria, exploit light as a source of information to control physiological processes via photoswitching between two states of different physiological activity, i.e. a red-absorbing Pr and a far-red-absorbing Pfr state. Depending on the relative stability in the dark, bacterial phytochromes are divided into prototypical and bathy phytochromes, where the stable state is Pr and Pfr, respectively. In this work we studied representatives of these groups (prototypical Agp1 and bathy Agp2 from Agrobacterium fabrum) together with the bathy-like phytochrome XccBphP from Xanthomonas campestris by resonance Raman and IR difference spectroscopy. In all three phytochromes, the photoinduced conversions display the same mechanistic pattern as reflected by the chromophore structures in the various intermediate states. We also observed in each case the secondary structure transition of the tongue, which is presumably crucial for the function of phytochrome. The three phytochromes differ in details of the chromophore conformation in the various intermediates and the energetic barrier of their respective decay reactions. The specific protein environment in the chromophore pocket, which is most likely the origin for these small differences, also controls the proton transfer processes concomitant to the photoconversions. These proton translocations, which are tightly coupled to the structural transition of the tongue, presumably proceed via the same mechanism along the Pr → Pfr conversion whereas the reverse Pfr → Pr photoconversion includes different proton transfer pathways. Finally, classification of phytochromes in prototypical and bathy (or bathy-like) phytochromes is discussed in terms of molecular structure and mechanistic properties.


Asunto(s)
Fitocromo , Bacterias/metabolismo , Proteínas Bacterianas/química , Fitocromo/química , Protones
9.
Biochemistry ; 60(4): 274-288, 2021 02 02.
Artículo en Inglés | MEDLINE | ID: mdl-33439010

RESUMEN

Cyanobacteriochromes (CBCRs) are cyanobacterial photoreceptors that exhibit photochromism between two states: a thermally stable dark-adapted state and a metastable light-adapted state with bound linear tetrapyrrole (bilin) chromophores possessing 15Z and 15E configurations, respectively. The photodynamics of canonical red/green CBCRs have been extensively studied; however, the time scales of their excited-state lifetimes and subsequent ground-state evolution rates widely differ and, at present, remain difficult to predict. Here, we compare the photodynamics of two closely related red/green CBCRs that have substantial sequence identity (∼68%) and similar chromophore environments: AnPixJg2 from Anabaena sp. PCC 7120 and NpR6012g4 from Nostoc punctiforme. Using broadband transient absorption spectroscopy on the primary (125 fs to 7 ns) and secondary (7 ns to 10 ms) time scales together with global analysis modeling, our studies revealed that AnPixJg2 and NpR6012g4 have comparable quantum yields for initiating the forward (15ZPr → 15EPg) and reverse (15EPg → 15ZPr) reactions, which proceed through monotonic and nonmonotonic mechanisms, respectively. In addition to small discrepancies in the kinetics, the secondary reverse dynamics resolved unique features for each domain: intermediate shunts in NpR6012g4 and a Meta-Gf intermediate red-shifted from the 15ZPr photoproduct in AnPixJg2. Overall, this study supports the conclusion that sequence similarity is a useful criterion for predicting pathways of the light-induced evolution and quantum yield of generating primary intermediate Φp within subfamilies of CBCRs, but more studies are still needed to develop a comprehensive molecular level understanding of these processes.


Asunto(s)
Anabaena/química , Proteínas Bacterianas/química , Luz , Nostoc/química
10.
Nicotine Tob Res ; 23(8): 1263-1273, 2021 08 04.
Artículo en Inglés | MEDLINE | ID: mdl-33155040

RESUMEN

INTRODUCTION: To review the geographic exposure measures used to characterize the tobacco environment in terms of density of tobacco outlets and proximity to tobacco outlets, and its association with smoking-related outcomes. METHODS: We used PubMed and Google Scholar to find articles published until December 2019. The search was restricted to studies that (1) measured the density of and/or proximity to tobacco outlets and (2) included associations with smoking outcomes. The extraction was coordinated by several observers. We gathered data on the place of exposure, methodological approaches, and smoking outcomes. RESULTS: Forty articles were eligible out of 3002 screened papers. Different density and proximity measures were described. 47.4% density calculations were based on simple counts (number of outlets within an area). Kernel density estimations and other measures weighted by the size of the area (outlets per square kilometer), population, and road length were identified. 81.3% of the articles which assessed proximity to tobacco outlets used length distances estimated through the street network. Higher density values were mostly associated with higher smoking prevalence (76.2%), greater tobacco use and smoking initiation (64.3%), and lower cessation outcomes (84.6%). Proximity measures were not associated with any smoking outcome except with cessation (62.5%). CONCLUSION: Associations between the density of tobacco outlets and smoking outcomes were found regardless of the exposure measure applied. Further research is warranted to better understand how proximity to tobacco outlets may influence the smoking outcomes. This systematic review discusses methodological gaps in the literature and provides insights for future studies exploring the tobacco environment. IMPLICATIONS: Our findings pose some methodological lessons to improve the exposure measures on the tobacco outlet environment. Solving these methodological gaps is crucial to understand the influence of the tobacco environment on the smoking outcomes. Activity spaces should be considered in further analyses because individuals are exposed to tobacco beyond their residence or school neighborhood. Further studies in this research area demand density estimations weighted by the size of the area, population, or road length, or measured using Kernel density estimations. Proximity calculations should be measured through the street network and should consider travel times apart from the length distance.


Asunto(s)
Nicotiana , Productos de Tabaco , Comercio , Humanos , Características de la Residencia , Fumar/epidemiología , Uso de Tabaco
11.
Phys Chem Chem Phys ; 23(33): 18197-18205, 2021 Sep 07.
Artículo en Inglés | MEDLINE | ID: mdl-34612283

RESUMEN

Bacterial phytochromes are sensoric photoreceptors that transform light absorbed by the photosensor core module (PCM) to protein structural changes that eventually lead to the activation of the enzymatic output module. The underlying photoinduced reaction cascade in the PCM starts with the isomerization of the tetrapyrrole chromophore, followed by conformational relaxations, proton transfer steps, and a secondary structure transition of a peptide segment (tongue) that is essential for communicating the signal to the output module. In this work, we employed various static and time-resolved IR and resonance Raman spectroscopic techniques to study the structural and reaction dynamics of the Meta-F intermediate of both the PCM and the full-length (PCM and output module) variant of the bathy phytochrome Agp2 from Agrobacterium fabrum. In both cases, this intermediate represents a branching point of the phototransformation, since it opens an unproductive reaction channel back to the initial state and a productive pathway to the final active state, including the functional protein structural changes. It is shown that the functional quantum yield, i.e. the events of tongue refolding per absorbed photons, is lower by a factor of ca. two than the quantum yield of the primary photochemical process. However, the kinetic data derived from the spectroscopic experiments imply an increased formation of the final active state upon increasing photon flux or elevated temperature under photostationary conditions. Accordingly, the branching mechanism does not only account for the phytochrome's function as a light intensity sensor but may also modulate its temperature sensitivity.


Asunto(s)
Agrobacterium/metabolismo , Proteínas Bacterianas/metabolismo , Luz , Fitocromo/metabolismo , Temperatura , Tetrapirroles/metabolismo , Agrobacterium/química , Proteínas Bacterianas/química , Fitocromo/química , Tetrapirroles/química
12.
Med Confl Surviv ; 37(2): 124-145, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34225496

RESUMEN

The Colombian armed conflict has disproportionately affected minorities, especially afro-Colombian communities. However, there is a lack of evidence about mental health of victims. This study aims to describe the prevalence of mental illness and its associated factors in Afro-descendant violence survivors in Buenaventura and Quibdó, Colombia. A cross-sectional study was carried out using data from a previous trial which aimed to reduce mental health symptoms (ClinicalTrials.gov: NCT01856673). Data of 710 adults identified through a snowball sampling technique was analysed. Diagnoses of depression, anxiety, post-traumatic stress disorder (PTSD), and dysfunction were established using adapted versions of the Hopkins Symptoms Checklist and the Harvard Trauma Questionnaire, plus variables identified in a qualitative study. Multivariate regressions were used to identify associated factors with these diagnoses. The prevalence of depression, anxiety and PTSD in both cities was 26.62% (95% confidence interval [95%CI]: 20.30;23.89), 36.53% (95%CI: 30.63;42.36), and 39.15% (95%CI: 33.36;44.83), respectively. Being married and having registered with the government as victim of the conflict were found to be protective factors for depression and PTSD, respectively. Psychological trauma, unemployment, and traumatic experiences, amongst others, were found as risk factors. The Colombian armed conflict, plus disparities and social exclusion, may be associated with mental health morbidity.


Asunto(s)
Salud Mental , Violencia , Adulto , Colombia/epidemiología , Estudios Transversales , Humanos , Sobrevivientes
13.
Biochemistry ; 59(9): 1023-1037, 2020 03 10.
Artículo en Inglés | MEDLINE | ID: mdl-32073262

RESUMEN

Phytochromes are biological photoswitches that interconvert between two parent states (Pr and Pfr). The transformation is initiated by photoisomerization of the tetrapyrrole chromophore, followed by a sequence of chromophore and protein structural changes. In the last step, a phytochrome-specific peptide segment (tongue) undergoes a secondary structure change, which in prokaryotic phytochromes is associated with the (de)activation of the output module. The focus of this work is the Pfr-to-Pr photoconversion of the bathy bacteriophytochrome Agp2 in which Pfr is the thermodynamically stable state. Using spectroscopic techniques, we studied the structural and functional consequences of substituting Arg211, Tyr165, His278, and Phe192 close to the biliverdin (BV) chromophore. In Pfr, substitutions of these residues do not affect the BV structure. The characteristic Pfr properties of bathy phytochromes, including the protonated propionic side chain of ring C (propC) of BV, are preserved. However, replacing Arg211 or Tyr165 blocks the photoconversion in the Meta-F state, prior to the secondary structure transition of the tongue and without deprotonation of propC. The Meta-F state of these variants displays low photochemical activity, but electronic excitation causes ultrafast alterations of the hydrogen bond network surrounding the chromophore. In all variants studied here, thermal back conversion from the photoproducts to Pfr is decelerated but substitution of His278 or Phe192 is not critical for the Pfr-to-Pr photoconversion. These variants do not impair deprotonation of propC or the α-helix/ß-sheet transformation of the tongue during the Meta-F-to-Pr decay. Thus, we conclude that propC deprotonation is essential for restructuring of the tongue.


Asunto(s)
Biliverdina/metabolismo , Fitocromo/química , Fitocromo/ultraestructura , Agrobacterium tumefaciens , Proteínas Bacterianas/química , Enlace de Hidrógeno , Luz , Fitocromo/fisiología , Protones , Espectrometría Raman/métodos , Tetrapirroles/química , Tetrapirroles/metabolismo
14.
Environ Res ; 183: 109142, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-32004828

RESUMEN

BACKGROUND: Cigarette butts are some of the most common form of litter in the World, causing severe environmental damage. Analysing spatial distribution of cigarette butts in the urban environment may lead to useful insights for further interventions to reduce this form of litter. In this study, we present a GIS-based methodology to estimate the density of cigarette butts across a large urban area. METHODS: We collected information about discarded cigarette butts in outdoor public spaces by systematic social observation in a diverse sample of areas in Madrid, Spain. We used these data to estimate the density of cigarette butts in public spaces around the entire city by performing GIS analyses based on Kernel Density Estimations. Last, we validated these measures using on-field observations in a set of locations across the city. RESULTS: Hospitality venues and public transportation stops were the places with the highest concentrations of cigarette butts, followed by the entrances to educational venues and playgrounds. Central districts showed the highest amount of cigarette butts in contrast to peripheral ones. We found that our measure had good validity, with a correlation coefficient of 0.784. DISCUSSION: This is the first study estimating and mapping cigarette butt litter in a large urban area. We identified a set of outdoor public places with high concentrations of cigarette butts and found geographical unevenness in the distribution of this pervasive form of litter across the study area. Our findings demonstrate the ubiquitous nature of cigarette butts in the urban environment and the need for interventions to reduce its impact on both people's health and the environment.


Asunto(s)
Fumar , Residuos Sólidos , Productos de Tabaco , Ciudades , Monitoreo del Ambiente , Sistemas de Información Geográfica , España
15.
Environ Res ; 180: 108888, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31706598

RESUMEN

BACKGROUND: Smoking visibility may affect smoking norms with implications for tobacco initiation, particularly amongst youths. Understanding how smoking is distributed across urban environments would contribute to the design and implementation of tobacco control policies. Our objective is to estimate the visibility of smokers in a large urban area using a novel GIS-based methodological approach. METHODS: We used systematic social observation to gather information about the presence of smokers in the environment within a representative sample of census tracts in Madrid city in 2016. We designed a GIS-based methodology to estimate the visibility of smokers throughout the whole city using the data collected in the fieldwork. Last, we validated our results in a sample of 40 locations distributed across the city through direct observation. RESULTS: We mapped estimates of smokers' visibility across the entire city. The visibility was higher in the central districts and in streets with a high density of hospitality venues, public transportation stops, and retail shops. Peripheral districts, with larger green areas and residential or industrial land uses, showed lower visibility of smokers. Validation analyses found high agreement between the estimated and observed values of smokers' visibility (R = 0.845, p=<0.001). DISCUSSION: GIS-based methods enable the development of novel tools to study the distribution of smokers and their visibility in urban environments. We found differences in the visibility by population density and leisure, retail shops and business activities. The findings can support the development of policies to protect people from smoking.


Asunto(s)
Fumadores , Productos de Tabaco , Contaminación por Humo de Tabaco , Adolescente , Ciudades , Sistemas de Información Geográfica , Humanos , Fumadores/estadística & datos numéricos , Fumar , Conducta Social
16.
Biochemistry ; 58(14): 1878-1891, 2019 04 09.
Artículo en Inglés | MEDLINE | ID: mdl-30768260

RESUMEN

The tiny picoalga, Ostreococcus tauri, originating from the Thau Lagoon is a member of the marine phytoplankton. Because of its highly reduced genome and small cell size, while retaining the fundamental requirements of a eukaryotic photosynthetic cell, it became a popular model organism for studying photosynthesis or circadian clock-related processes. We analyzed the spectroscopic properties of the photoreceptor domain of the histidine kinase rhodopsin Ot-HKR that is suggested to be involved in the light-induced entrainment of the Ostreococcus circadian clock. We found that the rhodopsin, Ot-Rh, dark state absorbs maximally at 505 nm. Exposure to green-orange light led to the accumulation of a blue-shifted M-state-like absorbance form with a deprotonated Schiff base. This Ot-Rh P400 state had an unusually long lifetime of several minutes. A second long-living photoproduct with a red-shifted absorbance, P560, accumulated upon illumination with blue/UVA light. The resulting photochromicity of the rhodopsin is expected to be advantageous to its function as a molecular control element of the signal transducing HKR domains. The light intensity and the ratio of blue vs green light are reflected by the ratio of rhodopsin molecules in the long-living absorbance forms. Furthermore, dark-state absorbance and the photocycle kinetics vary with the salt content of the environment substantially. This observation is attributed to anion binding in the dark state and a transient anion release during the photocycle, indicating that the salinity affects the photoinduced processes.


Asunto(s)
Proteínas Algáceas/metabolismo , Chlorophyta/metabolismo , Quinasa 1 del Receptor Acoplado a Proteína-G/metabolismo , Histidina Quinasa/metabolismo , Rodopsina/metabolismo , Agua de Mar/microbiología , Proteínas Algáceas/genética , Secuencia de Aminoácidos , Chlorophyta/genética , Chlorophyta/efectos de la radiación , Relojes Circadianos/efectos de la radiación , Ritmo Circadiano/efectos de la radiación , Quinasa 1 del Receptor Acoplado a Proteína-G/genética , Histidina Quinasa/genética , Cinética , Luz , Rodopsina/genética , Salinidad , Agua de Mar/química , Homología de Secuencia de Aminoácido , Transducción de Señal/efectos de la radiación , Espectroscopía Infrarroja por Transformada de Fourier
17.
Biochemistry ; 58(33): 3504-3519, 2019 08 20.
Artículo en Inglés | MEDLINE | ID: mdl-31348653

RESUMEN

Bacteriophytochromes harboring a biliverdin IXα (BV) chromophore undergo photoinduced reaction cascades to switch between physiologically inactive and active states. Employing vibrational spectroscopic and computational methods, we analyzed the role of propionic substituents of BV in the transformations between parent states Pr and Pfr in prototypical (Agp1) and bathy (Agp2) phytochromes from Agrobacterium fabrum. Both proteins form adducts with BV monoesters (BVM), esterified at propionic side chain B (PsB) or C (PsC), but in each case, only one monoester adduct is reactive. In the reactive Agp2-BVM-B complex (esterified at ring B), the Pfr dark state displays the structural properties characteristic of bathy phytochromes, including a protonated PsC. As in native Agp2, PsC is deprotonated in the final step of the Pfr phototransformation. However, the concomitant α-helix/ß-sheet secondary structure change of the tongue is blocked at the stage of unfolding of the coiled loop region. This finding and the shift of the tautomeric equilibrium of BVM toward the enol form are attributed to the drastic changes in the electrostatic potential. The calculations further suggest that deprotonation of PsC and the protonation state of His278 control the reactivity of the enol tautomer, thereby accounting for the extraordinarily slow thermal reversion. Although strong perturbations of the electrostatic potential are also found for Agp1-BVM, the consequences for the Pr-to-Pfr phototransformation are less severe. Specifically, the structural transition of the tongue is not impaired and thermal reversion is even accelerated. The different response of Agp1 and Agp2 to monoesterification of BV points to different photoconversion mechanisms.


Asunto(s)
Agrobacterium/metabolismo , Modelos Moleculares , Fitocromo/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/metabolismo , Biliverdina , Biología Computacional , Fitocromo/química , Conformación Proteica , Electricidad Estática
18.
Tob Control ; 28(3): 325-333, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-29991639

RESUMEN

BACKGROUND: In Spain, tobacco sales are limited to tobacco-exclusive stores and associated vending machines. A minimum of 150 m between stores is required, unless they exceed a legal sales threshold. Minimum distances to schools are recommended but not defined. We evaluated compliance with these regulations in Madrid, Spain. METHODS: Information about tobacco-exclusive stores and their sales volume was obtained in 2014. We used geographic information system to identify stores closer than 150 m between them and examine whether they exceeded the sales threshold. We estimated distances between stores and schools, considering different distance intervals (<150 m, 150-300 m and >300 m) and calculations (crow flies and street network). We assessed the association of area-level demographic and socioeconomic characteristics with the distribution of tobacco stores. RESULTS: 5.3% (34/638) of tobacco stores were within 150 m of each other. Among those, 76% (26/34) did not meet the regulation sales threshold. These stores were in areas with lower proportion of young population (<15 years) and higher proportion of people with university-level education. 75% (476/638) of stores were situated closer than 300 m to schools. No differences were identified in sociodemographic and economic characteristics by the store distance to schools. CONCLUSION: Most tobacco stores are compliant with the regulations in Spain. However, these regulations are insufficient to reduce tobacco availability. More restrictive regulations are needed to limit the geographic distribution of tobacco retailers, and health criteria should also be considered in the current legislation. The evaluation of the Spanish regulatory model may provide useful insights for other jurisdictions looking to decrease the tobacco retail availability.


Asunto(s)
Comercio/estadística & datos numéricos , Instituciones Académicas/legislación & jurisprudencia , Productos de Tabaco/economía , Comercio/legislación & jurisprudencia , Sistemas de Información Geográfica , Humanos , Factores Socioeconómicos , España , Productos de Tabaco/legislación & jurisprudencia , Productos de Tabaco/estadística & datos numéricos
19.
Environ Res ; 165: 220-227, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29727822

RESUMEN

INTRODUCTION: After the implementation of smoke-free policies in indoor hospitality venues (including bars, cafeterias, restaurants, and pubs), smokers may have been displaced to their outdoor areas. We aimed to study smoking visibility and second-hand smoke exposure in outdoor hospitality venues. METHODS: We collected information on signs of tobacco consumption on entrances and terraces of hospitality venues in 2016 in the city of Madrid, Spain. We further measured airborne nicotine concentrations and particulate matter of less than 2.5 µm in diameter (PM2.5) in terraces with monitors by active sampling during 30 min. We calculated the medians and the interquartile ranges (IQR) of nicotine and PM2.5 concentrations, and fitted multivariate models to characterize their determinants. RESULTS: We found 202 hospitality venues between May and September (summer), and 83 between October and December 2016 (fall) that were opened at the time of observation. We found signs of tobacco consumption on 78.2% of the outdoor main entrances and on 95.1% of outdoor terraces. We measured nicotine and PM2.5 concentrations in 92 outdoor terraces (out of the 123 terraces observed). Overall median nicotine concentration was 0.42 (IQR: 0.14-1.59) µg/m3, and overall PM2.5 concentration was 10.40 (IQR: 6.76-15.47) µg/m3 (statistically significantly higher than the background levels). Multivariable analyses showed that nicotine and PM2.5 concentrations increased when the terraces were completely closed, and when tobacco smell was noticed. Nicotine concentrations increased with the presence of cigarette butts, and when there were more than eight lit cigarettes at a time. CONCLUSIONS: Outdoor hospitality venues are areas where non-smokers, both employees and patrons, continue to be exposed to second-hand smoke. These spaces should be further studied and considered in future tobacco control interventions.


Asunto(s)
Contaminación del Aire/análisis , Exposición a Riesgos Ambientales/análisis , Contaminación por Humo de Tabaco/análisis , Ciudades , Nicotina/análisis , Material Particulado/análisis , Restaurantes , España
20.
BMC Med Educ ; 17(1): 254, 2017 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-29246229

RESUMEN

BACKGROUND: Gaps between evidence-based research and clinical-public health practice have been evident for decades. One of the aims of medical student research is to close this gap. Accordingly, evaluating individual and environmental factors that influence participation of medical students in research are needed to understand and identify potential targets for action. This study aims to identify characteristics of medical student researchers in Colombia and the associated factors with scientific publications. METHODS: A cross-sectional study of Colombian medical students involved in research using a validated, self-administered, online survey. The survey was distributed through the Colombian Association of Medical Students' Associations (ASCEMCOL). Data sets were analyzed using descriptive and summary statistics. Bivariate analysis and a multiple logistic regression model were conducted to identify predictors of scientific publications. RESULTS: A total of 133 responses were analyzed from students at 12 Colombian cities and 20 higher-education institutions. Although 94% of responders had at least one research proposal, only 57% had completed a project, and 17% had published their findings. Barriers for undertaking research included time restrictions and a lack of mentorship. Motivational factors included opportunity to publish findings and good mentorship. Students planning to do a specialization (OR = 3.25; 95% Confidence interval [CI] = 1.27-8.30), innovators (OR = 3.52; 95%CI = 1.30-9.52) and committed (OR = 3.39; 95%CI = 1.02-11.29), those who had previously published their findings (OR 9.13 IC95% 2.57-32.48), and were further in their medical education (OR 2.26 IC95% 1.01-5.07), were more likely to publish scientific papers. CONCLUSIONS: Our findings describe medical students understanding of the process of conducting research in Colombia. Although there appears to be motivation to participate in research, very few students achieve publication. Barriers such as time constraints and mentorship seem to play a critical role. This highlights opportunities where barriers to research can be overcome in medical school and other levels.


Asunto(s)
Investigación Biomédica/estadística & datos numéricos , Internado y Residencia , Publicaciones Periódicas como Asunto , Investigadores/educación , Facultades de Medicina , Investigación Biomédica/educación , Colombia/epidemiología , Estudios Transversales , Medicina Basada en la Evidencia , Femenino , Conocimientos, Actitudes y Práctica en Salud , Humanos , Masculino , Mentores , Guías de Práctica Clínica como Asunto , Estudiantes de Medicina , Adulto Joven
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