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1.
Nature ; 631(8020): 344-349, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38926575

RESUMEN

Many threats to biodiversity cannot be eliminated; for example, invasive pathogens may be ubiquitous. Chytridiomycosis is a fungal disease that has spread worldwide, driving at least 90 amphibian species to extinction, and severely affecting hundreds of others1-4. Once the disease spreads to a new environment, it is likely to become a permanent part of that ecosystem. To enable coexistence with chytridiomycosis in the field, we devised an intervention that exploits host defences and pathogen vulnerabilities. Here we show that sunlight-heated artificial refugia attract endangered frogs and enable body temperatures high enough to clear infections, and that having recovered in this way, frogs are subsequently resistant to chytridiomycosis even under cool conditions that are optimal for fungal growth. Our results provide a simple, inexpensive and widely applicable strategy to buffer frogs against chytridiomycosis in nature. The refugia are immediately useful for the endangered species we tested and will have broader utility for amphibian species with similar ecologies. Furthermore, our concept could be applied to other wildlife diseases in which differences in host and pathogen physiologies can be exploited. The refugia are made from cheap and readily available materials and therefore could be rapidly adopted by wildlife managers and the public. In summary, habitat protection alone cannot protect species that are affected by invasive diseases, but simple manipulations to microhabitat structure could spell the difference between the extinction and the persistence of endangered amphibians.


Asunto(s)
Anuros , Quitridiomicetos , Resistencia a la Enfermedad , Especies en Peligro de Extinción , Micosis , Refugio de Fauna , Animales , Anuros/inmunología , Anuros/microbiología , Anuros/fisiología , Temperatura Corporal/inmunología , Temperatura Corporal/fisiología , Temperatura Corporal/efectos de la radiación , Quitridiomicetos/inmunología , Quitridiomicetos/patogenicidad , Quitridiomicetos/fisiología , Resistencia a la Enfermedad/inmunología , Resistencia a la Enfermedad/fisiología , Resistencia a la Enfermedad/efectos de la radiación , Ecosistema , Micosis/veterinaria , Micosis/microbiología , Micosis/inmunología , Luz Solar , Animales Salvajes/inmunología , Animales Salvajes/microbiología , Animales Salvajes/fisiología , Especies Introducidas
2.
Mol Cell Neurosci ; 128: 103913, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38056728

RESUMEN

Fibroblast growth factors (FGFs) and bone morphogenic proteins (BMPs) play various important roles in the development of the central nervous system. However, the roles of FGF and BMP signaling in the development of the olfactory bulb (OB) are largely unknown. In this study, we first showed the expression of FGF receptors (FGFRs) and BMP receptors (BMPRs) in OB RGCs, radial glial cells (RGCs) in the developing OB, which generate the OB projection neurons, mitral and tufted cells. When the FGF signaling was inhibited by a dominant-negative form of FGFR1 (dnFGFR1), OB RGCs accelerated their state transition to mitral cell precursors without affecting their transcription cascade and fate. However, the mitral cell precursors could not radially migrate to form the mitral cell layer (MCL). In addition, FGF signaling inhibition reduced the expression of a BMP antagonist, Noggin, in the developing OB. When BMP signaling was suppressed by the ectopic expression of Noggin or a dominant-negative form of BMPR1a (dnBMPR1a) in the developing OB, the defect in MCL formation caused by the dnFGFR1 was rescued. However, the dnBMPR1a did not rescue the accelerated state transition of OB RGCs. These results demonstrate that FGF signaling is important for OB RGCs to maintain their self-renewal state and MCL formation. Moreover, the suppression of BMP signaling is required for mitral cells to form the MCL. This study sheds new light on the roles of FGFs and BMPs in OB development.


Asunto(s)
Proteínas Morfogenéticas Óseas , Bulbo Olfatorio , Ratones , Animales , Bulbo Olfatorio/metabolismo , Diferenciación Celular , Proteínas Morfogenéticas Óseas/metabolismo , Transducción de Señal , Factores de Crecimiento de Fibroblastos
3.
Drug Metab Dispos ; 2024 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-39029948

RESUMEN

An open-label, single-center, phase I study was conducted to determine the absolute bioavailability and absorption, distribution, metabolism, and excretion of capivasertib-a potent, selective AKT serine/threonine kinase inhibitor-in healthy males. In part 1, six participants received a single oral dose of capivasertib (400 mg; tablets) followed by a [14C]-radiolabeled intravenous microdose of capivasertib (100 µg). After a 14­day washout, five of the participants proceeded to part 2 and received a single oral dose of [14C]capivasertib (400 mg; solution). In part 1, median time of maximum observed concentration for capivasertib was 1.7 hours, geometric mean terminal elimination half-life was 12.9 hours, and absolute bioavailability was estimated at 28.6% (90% confidence interval, 23.9 to 34.2). In part 2, a high proportion of the administered radioactivity was recovered over the 168-hour sampling period (mean recovery: 95.1% [feces, 50.4%; urine, 44.7%]). Unchanged capivasertib in urine accounted for 7.4% of the total dose and 21.1% of the systemically available drug. Geometric mean renal clearance was 8.3 L/h, suggesting active tubular secretion. Twelve metabolites were identified in plasma. M11 (AZ14102143)-the glucuronide conjugate of capivasertib, inactive as an AKT serine/threonine kinase inhibitor-was the most abundant, accounting for a mean 78.4% of the plasma drug-related area under the curve. Of 22 metabolites identified in excreta, M11 was the most abundant (mean 28.2% of administered dose), indicating direct glucuronidation as one of the major routes of metabolism. No new safety concerns were identified. Significance Statement This study provides characterization of the pharmacokinetics of capivasertib-a potent, selective AKT serine/threonine kinase (AKT) inhibitor-including absolute bioavailability, mass balance, and metabolic fate in humans; the findings are being used to inform further clinical development. Absolute bioavailability was estimated at 28.6%, and mean recovery of the administered dose in excreta over 168 hours was 95.1%. M11 (AZ14102143)-the glucuronide conjugate, inactive as an AKT inhibitor-was the most abundant identified metabolite in plasma and excreta.

4.
Dysphagia ; 39(1): 33-42, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-37243730

RESUMEN

Videofluoroscopic swallow studies (VFSS) provide dynamic assessment of the phases of swallowing under fluoroscopic visualization and allow for identification of abnormalities in the process, such as laryngeal penetration and aspiration. While penetration and aspiration both reflect degrees of swallowing dysfunction, the predictive potential of penetration for subsequent aspiration is not fully elucidated in the pediatric population. As a result, management strategies for penetration vary widely. Some providers may interpret any depth or frequency of penetration as a proxy for aspiration and implement various therapeutic interventions (e.g., modification of liquid viscosity) to eliminate penetration episodes. Some may recommend enteral feeding given the presumed risk of aspiration with penetration, even when aspiration is not identified during the study. In contrast, other providers may advise continued oral feeding without modification even when some degree of laryngeal penetration is identified. We hypothesized that the depth of penetration is associated with the likelihood of aspiration. Identification of predictive factors for aspiration following laryngeal penetration events has significant implications for selection of appropriate interventions. We performed a retrospective cross-sectional analysis of a random sample of 97 patients who underwent VFSS in a single tertiary care center over a 6 month period. Demographic variables including primary diagnosis and comorbidities were analyzed. We examined the association between aspiration and degrees of laryngeal penetration (presence or absence, depth, frequency) across diagnostic categories. Infrequent and shallow penetration events of any type of viscosity were less likely to be associated with aspiration event(s) during the same clinical encounter regardless of diagnosis. In contrast, children with consistent deep penetration of thickened liquids invariably demonstrated aspiration during the same study. Our findings show that shallow, intermittent laryngeal penetration of any viscosity type on VFSS was not consistent with clinical aspiration. These results provide further evidence that penetration-aspiration is not a uniform clinical entity and that nuanced interpretation of videofluoroscopic swallowing findings is necessary to guide appropriate therapeutic interventions.


Asunto(s)
Trastornos de Deglución , Laringe , Humanos , Niño , Trastornos de Deglución/diagnóstico , Estudios Retrospectivos , Estudios Transversales , Deglución , Laringe/diagnóstico por imagen , Aspiración Respiratoria/diagnóstico , Aspiración Respiratoria/etiología , Fluoroscopía/métodos
5.
PLoS Comput Biol ; 18(8): e1010368, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-36037236

RESUMEN

Maintenance of epidermal thickness is critical to the barrier function of the skin. Decreased tissue thickness, specifically in the stratum corneum (the outermost layer of the tissue), causes discomfort and inflammation, and is related to several severe diseases of the tissue. In order to maintain both stratum corneum thickness and overall tissue thickness it is necessary for the system to balance cell proliferation and cell loss. Cell proliferation in the epidermis occurs in the basal layer and causes constant upwards movement in the tissue. Cell loss occurs when dead cells at the top of the tissue are lost to the environment through a process called desquamation. Desquamation is thought to occur through a gradual reduction in adhesion between cells, due to the cleaving of adhesion proteins by enzymes, in the stratum corneum. In this paper we will investigate combining a (mass action) subcellular model of desquamation with a three dimensional (cell centre based) multicellular model of the interfollicular epidermis to better understand maintenance of epidermal thickness. Specifically, our aim is to determine if a hypothesised biological model for the degradation of cell-cell adhesion, from the literature, is sufficient to maintain a steady state tissue thickness. These investigations show the model is able to provide a consistent rate of cell loss in the multicellular model. This loss balances proliferation, and hence maintains a homeostatic tissue thickness. Moreover, we find that multiple proliferative cell populations in the basal layer can be represented by a single proliferative cell population, simplifying investigations with this model. The model is used to investigate a disorder (Netherton Syndrome) which disrupts desquamation. The model shows how biochemical changes can cause disruptions to the tissue, resulting in a reduced tissue thickness and consequently diminishing the protective role of the tissue. A hypothetical treatment result is also investigated: we compare the cases of a partially effective homogeneous treatment (where all cells partially recover) and a totally effective heterogeneous treatment (in which a proportion of the cells totally recover) with the aim to determine the difference in the response of the tissue to these different scenarios. Results show an increased benefit to corneum thickness from the heterogeneous treatment over the homogeneous treatment.


Asunto(s)
Células Epidérmicas , Epidermis , Adhesión Celular , Proliferación Celular , Epidermis/fisiología , Proteínas/metabolismo
6.
Br J Clin Pharmacol ; 89(11): 3330-3339, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37328269

RESUMEN

AIMS: This two-part, adaptive study assessed the effect of food and an acid-reducing agent (rabeprazole) on the pharmacokinetics (PK) and safety of capivasertib, a potent AKT inhibitor, in clinical development for cancer treatment. METHODS: In Part 1, healthy participants (n = 24) were randomized to receive single-dose capivasertib after overnight fasting, a high-fat, high-calorie meal and with rabeprazole postovernight fasting in one of six treatment sequences. Based on Part 1 results, a new group of participants (n = 24) were randomized (Part 2) to receive capivasertib after overnight fasting, a low-fat, low-calorie meal and modified fasting (food restricted from 2 h before dosing to 1 h postdose) in one of six treatment sequences. Blood samples were collected for PK analyses. RESULTS: Following a high-fat, high-calorie meal, capivasertib exposure increased versus overnight fasting (geometric mean ratio [GMR] [90% confidence interval (CI)]: area under the concentration-time curve [AUCinf ] 1.32 [1.22, 1.43], maximum concentration [Cmax ] 1.23 [1.08, 1.41]), but was comparable to that postmodified fasting (GMR: AUCinf 1.13 [0.99, 1.29], Cmax 0.85 [0.70, 1.04]). AUCinf was similar and Cmax was lower with/without rabeprazole (GMR: AUCinf 0.94 [0.87, 1.02]), Cmax 0.73 [0.64, 0.84]). Capivasertib exposure was similar after a low-fat, low-calorie meal versus overnight fasting (GMR: AUCinf 1.14 [1.05, 1.25], Cmax 1.21 [0.99, 1.48]) or modified fasting (GMR: AUCinf 0.96 [0.88, 1.05], Cmax 0.86 [0.70, 1.06]). Safety was consistent with that in larger trials. CONCLUSIONS: This study demonstrates that administering capivasertib with food or acid-reducing agents does not lead to clinically relevant PK or safety profile changes.


Asunto(s)
Interacciones Alimento-Droga , Sustancias Reductoras , Humanos , Administración Oral , Área Bajo la Curva , Disponibilidad Biológica , Estudios Cruzados , Ayuno , Voluntarios Sanos , Rabeprazol/farmacocinética
7.
Environ Monit Assess ; 195(10): 1150, 2023 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-37668950

RESUMEN

Understanding the spatiotemporal dynamics of river water chemistry from its source to sinks is critical for constraining the origin, transformation, and "hotspots" of contaminants in a river basin. To provide new spatiotemporal constraints on river chemistry, dissolved trace element concentrations were measured at 17 targeted locations across the Ramganga River catchment. River water samples were collected across three seasons: pre-monsoon, monsoon, and post-monsoon between 2019 and 2021. To remove the dependency of trace element concentrations on discharge, we used molar ratios, as discharge data on Indian transboundary rivers are not publicly available. The dataset reveals significant spatiotemporal variability in dissolved trace element concentrations of the Ramganga River. Samples collected upstream of Moradabad, a major industrial city in western Uttar Pradesh, are characterized by ~ 1.2-2.5 times higher average concentrations of most of the trace elements except Sc, V, Cr, Rb, and Pb, likely due to intense water-rock interactions in the headwaters. Such kind of enrichment in trace metal concentrations was also observed at sites downstream of large cities and industrial centers. However, such enrichment was not enough to bring a major change in the River Ganga chemistry, as the signals got diluted downstream of the Ramganga-Ganga confluence. The average river water composition of the Ramganga River was comparable to worldwide river water composition, albeit a few sites were characterized by very high concentrations of dissolved trace elements. Finally, we provide an outlook that calls for an assessment of stable non-traditional isotopes that are ideally suited to track the origin and transformation of elements such as Li, Mg, Ca, Ti, V, Cr, Fe, Ni, Cu, Zn, Sr, Ag, Cd, Sn, Pt, and Hg in Indian rivers.


Asunto(s)
Monitoreo del Ambiente , Oligoelementos , Ríos , Agua Dulce , India , Agua
8.
Paediatr Respir Rev ; 44: 3-10, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36411238

RESUMEN

The current available literature evaluating pediatric multidisciplinary aerodigestive programs for the management of aerodigestive disorders in infants was reviewed. Multidisciplinary aerodigestive programs have emerged to provide coordinated and comprehensive care for the growing population of children with aerodigestive conditions, including complex airway, pulmonary, gastrointestinal, and feeding disorders, which are prevalent among infants discharged from the neonatal intensive care unit (NICU). The team approach central to aerodigestive clinics offers a comprehensive diagnostic workup and unified management plan through consolidated interdisciplinary clinics, combined endoscopic procedures, and regular team discussions, leading to improved resource utilization and health care outcomes. We review common conditions presenting in the NICU that benefit from the aerodigestive model of care, including esophageal atresia, prematurity, bronchopulmonary dysplasia with or without tracheostomy or ventilator dependence, and dysphagia.


Asunto(s)
Trastornos de Deglución , Atresia Esofágica , Enfermedades Respiratorias , Lactante , Recién Nacido , Niño , Humanos , Trastornos de Deglución/etiología , Trastornos de Deglución/terapia , Unidades de Cuidado Intensivo Neonatal , Sistema Respiratorio
9.
Eur J Neurosci ; 53(3): 895-901, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33378593

RESUMEN

A key issue facing cybercrime investigations is connecting online identities to real-world identities. This paper shows that by combining the Fringe-P3 method with a concealed information test, we can detect a participant's familiarity with their own email address, thus connecting their real-world identity to their online one. Participants were shown Rapid Serial Visual Presentation (RSVP) streams of email addresses, some including their own email address (probe) or a target email address. Familiarity with the probe was accurately detected with significant results at the group level and for 7 of 11 participants at the individual level. These promising results demonstrate that the method can be successfully used to detect online identities. Factors that may affect how well an email address probe stands out in the RSVP streams are also discussed.


Asunto(s)
Correo Electrónico , Reconocimiento en Psicología , Humanos
10.
Eur J Neurosci ; 54(6): 6168-6186, 2021 09.
Artículo en Inglés | MEDLINE | ID: mdl-34374142

RESUMEN

Excessive sensitivity to certain visual stimuli (cortical hyperexcitability) is associated with a number of neurological disorders including migraine, epilepsy, multiple sclerosis, autism and possibly dyslexia. Others show disruptive sensitivity to visual stimuli with no other obvious pathology or symptom profile (visual stress) which can extend to discomfort and nausea. We used event-related potentials (ERPs) to explore the neural correlates of visual stress and headache proneness. We analysed ERPs in response to thick (0.37 cycles per degree [c/deg]), medium (3 c/deg) and thin (12 c/deg) gratings, using mass univariate analysis, considering three factors in the general population: headache proneness, visual stress and discomfort. We found relationships between ERP features and the headache and discomfort factors. Stimulus main effects were driven by the medium stimulus regardless of participant characteristics. Participants with high discomfort ratings had larger P1 components for the initial presentation of medium stimuli, suggesting initial cortical hyperexcitability that is later suppressed. The participants with high headache ratings showed atypical N1-P2 components for medium stripes relative to the other stimuli. This effect was present only after repeated stimulus presentation. These effects were also explored in the frequency domain, suggesting variations in intertrial theta band phase coherence. Our results suggest that discomfort and headache in response to striped stimuli are related to different neural processes; however, more exploration is needed to determine whether the results translate to a clinical migraine population.


Asunto(s)
Deslumbramiento , Trastornos Migrañosos , Electroencefalografía , Fenómenos Electrofisiológicos , Humanos
11.
J Theor Biol ; 527: 110807, 2021 10 21.
Artículo en Inglés | MEDLINE | ID: mdl-34119497

RESUMEN

The maintenance of the proliferative cell niche is critical to epithelial tissue morphology and function. In this paper we investigate how current modelling methods can result in the erroneous loss of proliferative cells from the proliferative cell niche. Using an established model of the inter-follicular epidermis we find there is a limit to the proliferative cell densities that can be maintained in the basal layer (the niche) if we do not include additional mechanisms to stop the loss of proliferative cells from the niche. We suggest a new methodology that enables maintenance of a desired homeostatic population of proliferative cells in the niche: a rotational force is applied to the two daughter cells during the mitotic phase of division to enforce a particular division direction. We demonstrate that this new methodology achieves this goal. This methodology reflects the regulation of the orientation of cell division.


Asunto(s)
Células Epidérmicas , Células Epiteliales , División Celular , Epitelio , Humanos , Huso Acromático
12.
Acta Neurol Scand ; 142(6): 597-604, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32559313

RESUMEN

BACKGROUND: Treatment options for the subgroup of people who develop long-lasting symptoms following mild traumatic brain injury are limited. Transcranial pulsating low-frequency electromagnetic stimulation (T-PEMF) in other patient groups has shown promising results in several studies with proposed neuroprotective and anti-inflammatory effects. OBJECTIVE: The present pilot study was conducted to access feasibility and tolerability of T-PEMF in treating post-concussion syndrome. METHODS: Seven patients with post-concussion syndrome received 5 weeks of daily 30 minutes T-PEMF treatment with evaluation after 2 and 5 weeks and 3 months after ending treatment. RESULTS: Compliance was high as all subject completed the full treatment. Two patients however experienced a worsening of their concussion symptoms during the course of treatment. The remaining patients had some discomfort in relation to treatment, mainly headache, but passing and less for each treatment. The majority (n = 5) had a reduction in symptoms overall, up to 61% (2%-61%) based on the Rivermead Post-Concussion Symptoms Questionnaire. CONCLUSION: Further studies on T-PEMF as a treatment option for post-concussion syndrome are warranted.


Asunto(s)
Síndrome Posconmocional/terapia , Estimulación Magnética Transcraneal/efectos adversos , Estimulación Magnética Transcraneal/métodos , Adulto , Femenino , Humanos , Masculino , Proyectos Piloto
13.
Genet Med ; 21(7): 1639-1643, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30546084

RESUMEN

PURPOSE: There is little long-term, population-based data on uptake of prenatal diagnosis for Huntington disease (HD), a late-onset autosomal dominant neurodegenerative disorder, and the effect of the availability of preimplantation genetic diagnosis (PGD) on families' decisions about conventional prenatal diagnosis is not known. We report trends in prenatal diagnosis and preimplantation diagnosis for HD in the United Kingdom since services commenced. METHODS: Long-term UK-wide prospective case record-based service evaluation in 23 UK Regional Genetic Centres 1988-2015, and four UK PGD centers 2002-2015. RESULTS: From 1988 to 2015, 479 prenatal diagnoses were performed in the UK for HD. An exclusion approach was used in 150 (31%). The annual rate of HD prenatal diagnosis has remained around 18 (3.5/million) over 27 years, despite a steady increase in the use of PGD for HD since 2002. CONCLUSION: Although increasing number of couples are choosing either direct or exclusion PGD to prevent HD in their offspring, both direct and exclusion prenatal diagnosis remain important options in a health system where both PGD and prenatal diagnosis are state funded. At-risk couples should be informed of all options available to them, preferably prepregnancy.


Asunto(s)
Enfermedad de Huntington/diagnóstico , Diagnóstico Prenatal , Femenino , Humanos , Masculino , Embarazo , Diagnóstico Preimplantación , Estudios Prospectivos , Reino Unido
14.
Glob Chang Biol ; 25(10): 3365-3380, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31095834

RESUMEN

Cyanobacterial blooms are an increasing threat to water quality and global water security caused by the nutrient enrichment of freshwaters. There is also a broad consensus that blooms are increasing with global warming, but the impacts of other concomitant environmental changes, such as an increase in extreme rainfall events, may affect this response. One of the potential effects of high rainfall events on phytoplankton communities is greater loss of biomass through hydraulic flushing. Here we used a shallow lake mesocosm experiment to test the combined effects of: warming (ambient vs. +4°C increase), high rainfall (flushing) events (no events vs. seasonal events) and nutrient loading (eutrophic vs. hypertrophic) on total phytoplankton chlorophyll-a and cyanobacterial abundance and composition. Our hypotheses were that: (a) total phytoplankton and cyanobacterial abundance would be higher in heated mesocosms; (b) the stimulatory effects of warming on cyanobacterial abundance would be enhanced in higher nutrient mesocosms, resulting in a synergistic interaction; (c) the recovery of biomass from flushing induced losses would be quicker in heated and nutrient-enriched treatments, and during the growing season. The results supported the first and, in part, the third hypotheses: total phytoplankton and cyanobacterial abundance increased in heated mesocosms with an increase in common bloom-forming taxa-Microcystis spp. and Dolichospermum spp. Recovery from flushing was slowest in the winter, but unaffected by warming or higher nutrient loading. Contrary to the second hypothesis, an antagonistic interaction between warming and nutrient enrichment was detected for both cyanobacteria and chlorophyll-a demonstrating that ecological surprises can occur, dependent on the environmental context. While this study highlights the clear need to mitigate against global warming, oversimplification of global change effects on cyanobacteria should be avoided; stressor gradients and seasonal effects should be considered as important factors shaping the response.


Asunto(s)
Cianobacterias , Fitoplancton , Eutrofización , Lagos , Nutrientes
15.
J Am Chem Soc ; 140(21): 6540-6544, 2018 05 30.
Artículo en Inglés | MEDLINE | ID: mdl-29723466

RESUMEN

An octacationic diazaperopyrenium (DAPP2+)-based homo[2]catenane (DAPPHC8+), wherein no fewer than eight positive charges are associated within a mechanically interlocked molecule, has been produced in 30% yield under ambient conditions as a result of favorable homophilic interactions, reflecting a delicate balance between strong π-π interactions and the destabilizing penalty arising from Coulombic repulsions between DAPP2+ units. This DAPPHC8+ catenane is composed of two identical mechanically interlocked tetracationic cyclophanes, namely DAPPBox4+, each of which contains one DAPP2+ unit and one extended viologen (ExBIPY2+) unit, linked together by two p-xylylene bridges. The solid-state structure of the homo[2]catenane demonstrates how homophilic interactions play an important role in the formation of DAPPHC8+, in which the mean ring planes of the two DAPPBox4+ cyclophanes are oriented at about 60° with respect to each other, with a centroid-to-centroid separation of 3.7 Å between the mean planes of the outer ExBIPY2+ and inner DAPP2+ units, and 3.6 Å between the mean planes of the two inner DAPP2+ units. We show that irradiation of the DAPPHC8+ catenane at 330 nm in acetonitrile solution results in simultaneous energy and electron transfer. The latter occurs from the inner DAPP2+ dimer to the outer ExBIPY2+ unit, leading to the generation of a temporary charge-separated state within a rigid and robust homo[2]catenane. Compared to DAPPBox4+, both forward- and back-electron transfer in DAPPHC8+ occur with faster rates, owing to the closer proximity between the electron donor and acceptor in the homo[2]catenane than in the separated cyclophane.

16.
J Clin Microbiol ; 56(9)2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29997200

RESUMEN

Escherichia coli is the most common cause of human and canine urinary tract infection (UTI). Clonal groups, often with high levels of antimicrobial resistance, are a major component of the E. coli population that causes human UTI. While little is known about the population structure of E. coli that causes UTI in dogs, there is evidence that dogs and humans can share fecal strains of E. coli and that human-associated strains can cause disease in dogs. In order to better characterize the E. coli strains that cause canine UTI, we analyzed 295 E. coli isolates obtained from canine urine samples from five veterinary diagnostic laboratories and analyzed their multilocus sequence types, phenotypic and genotypic antimicrobial resistance profiles, and virulence-associated gene repertoires. Sequence type 372 (ST372), an infrequent human pathogen, was the predominant sequence type in dogs at all locations. Extended-spectrum ß-lactamase-producing isolates with blaCTX-M genes were uncommon in canine isolates but when present were often associated with sequence types that have been described in human infections. This provides support for occasional cross-host-species sharing of strains that cause extraintestinal disease and highlights the importance of understanding the role of companion animals in the overall transmission patterns of extraintestinal pathogenic E. coli.


Asunto(s)
Enfermedades de los Perros/microbiología , Farmacorresistencia Bacteriana/genética , Infecciones por Escherichia coli/veterinaria , Infecciones Urinarias/veterinaria , Escherichia coli Uropatógena/clasificación , Escherichia coli Uropatógena/efectos de los fármacos , Animales , Antibacterianos/farmacología , Perros , Infecciones por Escherichia coli/microbiología , Femenino , Genes Bacterianos/genética , Genotipo , Humanos , Masculino , Pruebas de Sensibilidad Microbiana , Tipificación de Secuencias Multilocus/veterinaria , Fenotipo , Filogenia , Factores de Riesgo , Estados Unidos , Infecciones Urinarias/microbiología , Escherichia coli Uropatógena/genética , Virulencia/genética
17.
Genet Med ; 20(12): 1575-1582, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29565421

RESUMEN

PURPOSE: BRCA1/BRCA2 predictive test negatives are proven noncarriers of a BRCA1/BRCA2 mutation that is carried by their relatives. The risk of developing breast cancer (BC) or epithelial ovarian cancer (EOC) in these women is uncertain. The study aimed to estimate risks of invasive BC and EOC in a large cohort of BRCA1/BRCA2 predictive test negatives. METHODS: We used cohort analysis to estimate incidences, cumulative risks, and standardized incidence ratios (SIRs). RESULTS: A total of 1,895 unaffected women were eligible for inclusion in the BC risk analysis and 1,736 in the EOC risk analysis. There were 23 incident invasive BCs and 2 EOCs. The cumulative risk of invasive BC was 9.4% (95% confidence interval (CI) 5.9-15%) by age 85 years and the corresponding risk of EOC was 0.6% (95% CI 0.2-2.6%). The SIR for invasive BC was 0.93 (95% CI 0.62-1.40) in the overall cohort, 0.85 (95% CI 0.48-1.50) in noncarriers from BRCA1 families, and 1.03 (95% CI 0.57-1.87) in noncarriers from BRCA2 families. The SIR for EOC was 0.79 (95% CI 0.20-3.17) in the overall cohort. CONCLUSION: Our results did not provide evidence for elevated risks of invasive BC or EOC in BRCA1/BRCA2 predictive test negatives.


Asunto(s)
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Neoplasias Ováricas/genética , Adulto , Anciano , Neoplasias de la Mama/diagnóstico , Neoplasias de la Mama/epidemiología , Femenino , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/diagnóstico , Neoplasias Ováricas/epidemiología , Medición de Riesgo , Factores de Riesgo
18.
J Vasc Surg ; 67(4): 1227-1233, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-29122421

RESUMEN

OBJECTIVE: High-resolution fixed C-arm fluoroscopic systems allow high-quality endovascular imaging but come at a cost of greater scatter radiation generation and increased occupational exposure for surgeons. The purpose of this study was to evaluate the efficacy of two methods in reducing scattered radiation exposure. METHODS: There were 164 endovascular cases analyzed in three phases. In phase 1 (P1), baseline radiation exposure was calculated. In phase 2 (P2), staff used real-time radiation dose monitoring (dosimetry badges [RaySafe; Unfors, Hopkinton, Mass]). In phase 3 (P3), a software imaging algorithm was installed that reduced radiation (EcoDose software; Philips Healthcare, Best, The Netherlands). RESULTS: A total of 72 cases in P1, 34 cases in P2, and 58 cases in P3 were analyzed. Total mean dose-area product decreased across each phase, with statistical significance achieved for P1 vs P3 (mean ± standard error of the mean, 186,173 ± 16,754 mGy/cm2 vs 121,536 ± 11,971 mGy/cm2; P = .002) and P2 vs P3 (171,921 ± 26,276 mGy/cm2 vs 121,536 ± 11,971 mGy/cm2; P = .04), whereas total mean fluoroscopy time did not significantly differ across any phase. The radiation exposure to the primary operator did not change significantly from P1 to P2 but fell significantly in P3 (0.08 ± 0.02 mSv vs 0.03 ± 0.01 mSv; P = .02). The addition of dose reduction software had the most impact on endovascular aneurysm repair, with reductions in median room dose (P = .03) and primary operator exposure (P2 vs P3; 0.19 ± 0.04 mSv vs 0.03 ± 0.02 mSv; P < .01). CONCLUSIONS: Dose reduction software may be an effective technique to lower radiation exposure. Implementation of system-based strategies to reduce radiation is needed to reduce lifetime occupational radiation exposure for endovascular staff and to improve patient safety.


Asunto(s)
Angiografía/métodos , Procedimientos Endovasculares/métodos , Exposición Profesional/prevención & control , Salud Laboral , Quirófanos , Dosis de Radiación , Exposición a la Radiación/prevención & control , Radiografía Intervencional/métodos , Dispersión de Radiación , Algoritmos , Angiografía/efectos adversos , Aortografía , Procedimientos Endovasculares/efectos adversos , Fluoroscopía , Humanos , Exposición Profesional/efectos adversos , Ohio , Estudios Prospectivos , Exposición a la Radiación/efectos adversos , Monitoreo de Radiación , Radiografía Intervencional/efectos adversos , Medición de Riesgo , Factores de Riesgo , Programas Informáticos
19.
Glob Chang Biol ; 24(11): 5044-5055, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30005138

RESUMEN

Blooms of cyanobacteria are a current threat to global water security that is expected to increase in the future because of increasing nutrient enrichment, increasing temperature and extreme precipitation in combination with prolonged drought. However, the responses to multiple stressors, such as those above, are often complex and there is contradictory evidence as to how they may interact. Here we used broad scale data from 494 lakes in central and northern Europe, to assess how cyanobacteria respond to nutrients (phosphorus), temperature and water retention time in different types of lakes. Eight lake types were examined based on factorial combinations of major factors that determine phytoplankton composition and sensitivity to nutrients: alkalinity (low and medium-high), colour (clear and humic) and mixing intensity (polymictic and stratified). In line with expectations, cyanobacteria increased with temperature and retention time in five of the eight lake types. Temperature effects were greatest in lake types situated at higher latitudes, suggesting that lakes currently not at risk could be affected by warming in the future. However, the sensitivity of cyanobacteria to temperature, retention time and phosphorus varied among lake types highlighting the complex responses of lakes to multiple stressors. For example, in polymictic, medium-high alkalinity, humic lakes cyanobacteria biovolume was positively explained by retention time and a synergy between TP and temperature, while in polymictic, medium-high alkalinity, clear lakes only retention time was identified as an explanatory variable. These results show that, although climate change will need to be accounted for when managing the risk of cyanobacteria in lakes, a "one-size fits-all" approach is not appropriate. When forecasting the response of cyanobacteria to future environmental change, including changes caused by climate and local management, it will be important to take this differential sensitivity of lakes into account.


Asunto(s)
Cianobacterias , Lagos/microbiología , Cambio Climático , Ambiente , Europa (Continente) , Fósforo/análisis , Fitoplancton
20.
J Am Chem Soc ; 139(2): 663-671, 2017 01 18.
Artículo en Inglés | MEDLINE | ID: mdl-27977196

RESUMEN

Singlet exciton fission (SF) in organic chromophore assemblies results in the conversion of one singlet exciton (S1) into two triplet excitons (T1), provided that the overall process is exoergic, i.e., E(S1) > 2E(T1). We report on SF in thin polycrystalline films of two terrylene-3,4:11,12-bis(dicarboximide) (TDI) derivatives 1 and 2, which crystallize into two distinct π-stacked structures. Femtosecond transient absorption spectroscopy (fsTA) reveals a charge-transfer state preceding a 190% T1 yield in films of 1, where the π-stacked TDI molecules are rotated by 23° along an axis perpendicular to their π systems. In contrast, when the TDI molecules are slip-stacked along their N-N axes in films of 2, fsTA shows excimer formation, followed by a 50% T1 yield.

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