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1.
Immunity ; 56(8): 1939-1954.e12, 2023 08 08.
Artículo en Inglés | MEDLINE | ID: mdl-37442134

RESUMEN

Lung infection during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) via the angiotensin-I-converting enzyme 2 (ACE2) receptor induces a cytokine storm. However, the precise mechanisms involved in severe COVID-19 pneumonia are unknown. Here, we showed that interleukin-10 (IL-10) induced the expression of ACE2 in normal alveolar macrophages, causing them to become vectors for SARS-CoV-2. The inhibition of this system in hamster models attenuated SARS-CoV-2 pathogenicity. Genome-wide association and quantitative trait locus analyses identified a IFNAR2-IL10RB readthrough transcript, COVID-19 infectivity-enhancing dual receptor (CiDRE), which was highly expressed in patients harboring COVID-19 risk variants at the IFNAR2 locus. We showed that CiDRE exerted synergistic effects via the IL-10-ACE2 axis in alveolar macrophages and functioned as a decoy receptor for type I interferons. Collectively, our data show that high IL-10 and CiDRE expression are potential risk factors for severe COVID-19. Thus, IL-10R and CiDRE inhibitors might be useful COVID-19 therapies.


Asunto(s)
COVID-19 , Humanos , COVID-19/genética , SARS-CoV-2 , Enzima Convertidora de Angiotensina 2/genética , Interleucina-10/genética , Macrófagos Alveolares/metabolismo , Estudio de Asociación del Genoma Completo , Peptidil-Dipeptidasa A/metabolismo
2.
J Evol Biol ; 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38656295

RESUMEN

Quantitative genetic theory on multivariate character evolution predicts that a population's response to directional selection is biased toward the major axis of the genetic covariance matrix G-the so-called genetic line of least resistance. Inferences on the genetic constraints in this sense have traditionally been made by measuring the angle of deviation of evolutionary trajectories from the major axis, or more recently by calculating the amount of genetic variance-the Hansen-Houle evolvability-available along the trajectories. However, there have not been clear practical guidelines on how these quantities can be interpreted, especially in a high-dimensional space. This study summarizes pertinent distribution theories for relevant quantities, pointing out that they can be written as ratios of quadratic forms in evolutionary trajectory vectors by taking G as a parameter. For example, a beta distribution with appropriate parameters can be used as a null distribution for squared cosine of the angle of deviation from a major axis or subspace. More general cases can be handled with the probability distribution of ratios of quadratic forms in normal variables. Apart from its use in hypothesis-testing, this latter approach could potentially be used as a heuristic tool for looking into various selection scenarios like directional and/or correlated selection as parameterized with mean and covariance of selection gradients.

3.
J Math Biol ; 86(6): 95, 2023 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-37217733

RESUMEN

Theory predicts that the additive genetic covariance ([Formula: see text]) matrix determines a population's short-term (in)ability to respond to directional selection-evolvability in the Hansen-Houle sense-which is typically quantified and compared via certain scalar indices called evolvability measures. Often, interest is in obtaining the averages of these measures across all possible selection gradients, but explicit formulae for most of these average measures have not been known. Previous authors relied either on approximations by the delta method, whose accuracy is generally unknown, or Monte Carlo evaluations (including the random skewers analysis), which necessarily involve random fluctuations. This study presents new, exact expressions for the average conditional evolvability, average autonomy, average respondability, average flexibility, average response difference, and average response correlation, utilizing their mathematical structures as ratios of quadratic forms. The new expressions are infinite series involving top-order zonal and invariant polynomials of matrix arguments, and can be numerically evaluated as their partial sums with, for some measures, known error bounds. Whenever these partial sums numerically converge within reasonable computational time and memory, they will replace the previous approximate methods. In addition, new expressions are derived for the average measures under a general normal distribution for the selection gradient, extending the applicability of these measures into a substantially broader class of selection regimes.


Asunto(s)
Algoritmos , Método de Montecarlo
4.
Biol Lett ; 18(2): 20210638, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-35168376

RESUMEN

Parallelism between evolutionary trajectories in a trait space is often seen as evidence for repeatability of phenotypic evolution, and angles between trajectories play a pivotal role in the analysis of parallelism. However, properties of angles in multidimensional spaces have not been widely appreciated by biologists. To remedy this situation, this study provides a brief overview on geometric and statistical aspects of angles in multidimensional spaces. Under the null hypothesis that trajectory vectors have no preferred directions (i.e. uniform distribution on hypersphere), the angle between two independent vectors is concentrated around the right angle, with a more pronounced peak in a higher-dimensional space. This probability distribution is closely related to t- and beta distributions, which can be used for testing the null hypothesis concerning a pair of trajectories. A recently proposed method with eigenanalysis of a vector correlation matrix can be connected to the test of no correlation or concentration of multiple vectors, for which simple test procedures are available in the statistical literature. Concentration of vectors can also be examined by tools of directional statistics such as the Rayleigh test. These frameworks provide biologists with baselines to make statistically justified inferences for (non)parallel evolution.


Asunto(s)
Evolución Biológica , Fenotipo
5.
Int Heart J ; 61(2): 338-346, 2020 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-32173709

RESUMEN

Sympathetic nerve activity has arrhythmogenic potential for ventricular arrhythmias associated with structural heart diseases. However, a sufficient amount of beta-blockers occasionally cannot be prescribed in some patients.An experimental study was performed to clarify the therapeutic effects of bepridil, a multiple ionic current inhibitor that does not affect beta-adrenergic receptors, for premature beats occurring during enhanced sympathetic nerve activity. Cardio-sympathetic nerve activity was augmented via stellate-ganglion (SG) stimulation in a canine model (n = 8), and the arrhythmogenic potential and anti-arrhythmic effects of bepridil (2 and 4 mg/kg intravenously) were assessed. For safe use, vagal-stimulation-induced slow HR and programmed electrical stimulation were applied to evaluate possible pro-arrhythmic effects of the drug. Heart rate variability (HRV) indexes were used to estimate cardio-autonomic nerve activity.Either side of the SG-stimulation increased BP and HR. Premature beats were induced in 10/16 SG-stimulations and it was more frequent in left (8/8) rather than right stimulation (2/8). Following 2 mg/kg drug administration, premature beats were still inducible in 8/16 stimulations (7/8 in left and 1/8 in right), but burden of the premature beats decreased from 87.1 ± 46.8 to 62.1 ± 42.6 beats. After 4 mg/kg administration, premature beats were inducible in one SG-stimulation. Proarrhythmic effects were not observed in all experiments. Steady-state HRV indexes and percent increases in SG-stimulation-induced BP-elevation and HR-acceleration were similar among the 3 periods (before, 2 and 4 mg/kg of the drug).Bepridil may be an option for ventricular arrhythmias developed during enhanced cardio-sympathetic nerve activity with minimal effect on autonomic nerve responses.


Asunto(s)
Antiarrítmicos/uso terapéutico , Bepridil/uso terapéutico , Complejos Prematuros Ventriculares/tratamiento farmacológico , Animales , Antiarrítmicos/farmacología , Bepridil/farmacología , Presión Sanguínea/efectos de los fármacos , Perros , Evaluación Preclínica de Medicamentos , Estimulación Eléctrica , Electrocardiografía/efectos de los fármacos , Frecuencia Cardíaca/efectos de los fármacos , Ganglio Estrellado
6.
Int Heart J ; 60(5): 1161-1167, 2019 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-31484866

RESUMEN

Therapy-resistant ventricular arrhythmias can occur during accidental advanced hypothermic conditions. On the other hand, hypothermic therapy using mild cooling has been successfully accomplished with infrequent ventricular arrhythmia events.To further clarify the therapeutic-resistant arrhythmogenic substrate which develops in hypothermic conditions, an experimental study was performed using a perfusion wedge preparation model of porcine ventricle, and electrophysiological characteristics, inducibility of ventricular arrhythmias, and effects of therapeutic interventions were assessed at 3 target temperatures (37, 32 and 28°C).As the myocardial temperature decreased, myocardial contractions and the number of spontaneous beats deceased. Depolarization (QRS width, stimulus-QRS interval) and repolarization (QT interval, ERP) parameters progressively increased, and dispersion of the ventricular repolarization increased. At 28°C, VF tended to be inducible more frequently (1/11 at 37°C, 1/11 at 32°C, and 5/11 hearts at 28°C), and some VFs at 28°C required greater defibrillation energy to resume basic rhythm.An advanced but not a mild hypothermic condition had an enhanced arrhythmogenic potential in our model. In the advanced hypothermic condition, VF with relatively prolonged F-F intervals and a greater defibrillation energy were occasionally inducible based on the arrhythmogenic substrate characterized as slowed conduction and prolonged repolarization of the ventricle.


Asunto(s)
Antiarrítmicos/administración & dosificación , Electrocardiografía/métodos , Hipotermia Inducida/métodos , Fibrilación Ventricular/diagnóstico por imagen , Fibrilación Ventricular/terapia , Análisis de Varianza , Animales , Arritmias Cardíacas/fisiopatología , Arritmias Cardíacas/terapia , Electrofisiología Cardíaca/métodos , Modelos Animales de Enfermedad , Resistencia a Medicamentos , Distribución Aleatoria , Medición de Riesgo , Porcinos , Resultado del Tratamiento
7.
Pacing Clin Electrophysiol ; 40(3): 223-231, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-27943352

RESUMEN

BACKGROUND: During bipolar (BIP) radiofrequency (RF) ablation using two catheters in humans, each catheter is placed in separate cardiac chambers or spaces. We developed a contact force-controlled experimental preparation, and compared measurements made with two catheters placed in a single bath (SB), versus each catheter placed in separate baths, in order to assess the preparation-dependent differences in the results of BIP-RF ablation. METHODS: In the SB experiments, a porcine heart was placed in the center of the bath, while in the dual-bath (DB) experiments, it was placed between two half baths communicating through windows. RESULTS: The initial impedance was greatest (110.5 ± 7.2 Ω) with the BIP-DB, followed by the BIP-SB (92.0 ± 5.6 Ω) and the unipolar (UNIP) DB (84.9 ± 4.7 Ω) configurations. During 50-W ablation for 60 seconds at a 20-g contact force, the root mean square voltage was 75.7 ± 2.5 V in the BIP-DB, 68.0 ± 2.1 V in the BIP-SB, and 66.8 ± 2.0 V in the UNIP-DB. The mean surface lesion diameters were similar among the three configurations. However, the endocardial lesion depth was 5.60 ± 0.56 mm with the BIP-DB, 4.71 ± 0.64 mm with the BIP-SB, and 4.24 ± 0.58 mm with the UNIP-DB configuration. On average, the endocardial lesions were significantly deeper than the epicardial ones. CONCLUSIONS: BIP ablation created much deeper lesions as compared to UNIP ablation. Lesion depth could be different depending on experimental preparation, and contact force-controlled DB preparation may be a much more appropriate model for studying the effects of BIP ablation.


Asunto(s)
Electrodos , Ventrículos Cardíacos/patología , Ventrículos Cardíacos/cirugía , Modelos Animales , Técnicas de Cultivo de Órganos/métodos , Cloruro de Sodio/química , Animales , Impedancia Eléctrica , Diseño de Equipo , Análisis de Falla de Equipo , Presión , Estrés Mecánico , Porcinos
8.
J Comp Pathol ; 203: 19-22, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-37207418

RESUMEN

A 1 year and 2-months-old neutered male cat underwent surgical resection of a cutaneous nodule on the midline of the forehead that had been present since approximately 6 months of age. Histopathologically, the nodule was composed of interlacing collagenous fibres interspersed with varying numbers of spindloid cells with round to oval nuclei and moderate to abundant amounts of pale eosinophilic cytoplasm. Similar to meningothelial cells, the spindloid cells were immunopositive for vimentin, neuron-specific enolase, E-cadherin and somatostatin receptor 2. Based on these findings and the absence of nuclear atypia and mitotic figures, the nodule was diagnosed as meningothelial hamartoma. Although cases of cutaneous meningioma have been reported, this is the first report of meningothelial hamartoma in a domestic animal.


Asunto(s)
Hamartoma , Neoplasias Cutáneas , Masculino , Animales , Frente , Hamartoma/veterinaria , Neoplasias Cutáneas/veterinaria
9.
Evolution ; 76(1): 4-28, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34679186

RESUMEN

Analysis of trait covariation plays a pivotal role in the study of phenotypic evolution. The magnitude of covariation is often quantified with statistics based on dispersion of eigenvalues of a covariance or correlation matrix-eigenvalue dispersion indices. This study clarifies the statistical justifications of these statistics and elaborates on their sampling properties. The relative eigenvalue variance of a covariance matrix is known in the statistical literature a test statistic for sphericity, and thus is an appropriate measure of eccentricity of variation. The same of a correlation matrix is equal to the average squared correlation, which has a straightforward interpretation as a measure of integration. Here, expressions for the mean and variance of these statistics are analytically derived under multivariate normality, clarifying the effects of sample size N, number of variables p, and parameters on sampling bias and error. Simulations confirm that approximations involved are reasonably accurate with a moderate sample size (N ≥ 16-64). Importantly, sampling properties of these indices are not adversely affected by a high p:N ratio, promising their utility in high-dimensional phenotypic analyses. They can furthermore be applied to shape variables and phylogenetically structured data with appropriate modifications.


Asunto(s)
Evolución Biológica , Fenotipo , Tamaño de la Muestra
10.
Integr Org Biol ; 3(1): obaa040, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34258512

RESUMEN

Despite longstanding interest in convergent evolution, factors that result in deviations from fully convergent phenotypes remain poorly understood. In birds, the evolution of flightless wing-propelled diving has emerged as a classic example of convergence, having arisen in disparate lineages including penguins (Sphenisciformes) and auks (Pan-Alcidae, Charadriiformes). Nevertheless, little is known about the functional anatomy of the wings of flightless auks because all such taxa are extinct, and their morphology is almost exclusively represented by skeletal remains. Here, in order to re-evaluate the extent of evolutionary convergence among flightless wing-propelled divers, wing muscles and ligaments were reconstructed in two extinct flightless auks, representing independent transitions to flightlessness: Pinguinus impennis (a crown-group alcid), and Mancalla (a stem-group alcid). Extensive anatomical data were gathered from dissections of 12 species of extant charadriiforms and 4 aequornithine waterbirds including a penguin. The results suggest that the wings of both flightless auk taxa were characterized by an increased mechanical advantage of wing elevator/retractor muscles, and decreased mobility of distal wing joints, both of which are likely advantageous for wing-propelled diving and parallel similar functional specializations in penguins. However, the conformations of individual muscles and ligaments underlying these specializations differ markedly between penguins and flightless auks, instead resembling those in each respective group's close relatives. Thus, the wings of these flightless wing-propelled divers can be described as convergent as overall functional units, but are incompletely convergent at lower levels of anatomical organization-a result of retaining differing conditions from each group's respective volant ancestors. Detailed investigations such as this one may indicate that, even in the face of similar functional demands, courses of phenotypic evolution are dictated to an important degree by ancestral starting points.


La reconstruction de la musculature des ailes d'espèces éteintes de pingouins non-volants (Pinguinus et Mancalla) révèle une convergence incomplète avec les manchots (Spheniscidae) expliquée par des états ancestraux différentsMalgré un intérêt de longue date pour l'évolution convergente, les facteurs limitant l'evolution de phénotypes entièrement convergents restent mal compris. Chez les oiseaux, l'évolution de la plongée propulsée par les ailes, associée à une perte de la capacité de vol, est devenue un exemple classique de convergence, apparue dans des lignées disparates telles que les manchots (Sphenisciformes) et les pingouins (Pan-Alcidae, Charadriiformes). On sait cependant peu de choses sur l'anatomie fonctionnelle des ailes des pingouins non-volants, car tous sont éteints et leur morphologie est presque exclusivement représentée par des restes squelettiques. Ici, afin de réévaluer l'étendue de la convergence évolutive chez les espèces non-volantes d'oiseaux plongeurs propulsés par leurs ailes, les muscles des ailes et les ligaments ont été reconstruits chez deux espèces éteintes de pingouins non-volants. Ces espèces représentent des transitions indépendantes vers l'inaptitude à voler : Pinguinus impennis (un alcidé du groupe-couronne) et Mancalla (un alcidé du groupe-tronc). Des données anatomiques approfondies ont été recueillies à partir des dissections de 12 espèces actuelles de Charadriiformes et de 4 espèces d'oiseaux d'eau Aequornithes, dont un manchot. Les résultats suggèrent que les ailes des deux taxons de pingouins non-volants étaient caractérisées par un avantage mécanique accru des muscles alaires élévateurs / rétracteurs, et par une mobilité réduite des articulations distales de l'aile. Ces deux éléments sont probablement avantageux pour la plongée propulsée par les ailes, et représentent des spécialisations fonctionnelles similaires à celles des manchots. Cependant, les conformations des muscles et des ligaments individuels sous-jacents à ces spécialisations diffèrent nettement entre les manchots et les pingouins non-volants. Ces conformations ressemblent ainsi plutôt à celles des taxons proches de chaque groupe respectif. Chez ces oiseaux plongeurs non-volants propulsés par les ailes, les ailes peuvent être décrites comme convergentes en tant qu'unités fonctionnelles globales, mais sont incomplètement convergentes à des niveaux inférieurs d'organisation anatomique. C'est le résultat du maintien de conditions différentes héritées des ancêtres volants respectifs de chaque groupe. Des recherches détaillées comme celle-ci peuvent indiquer que, même face à des exigences fonctionnelles similaires, le cours de l'évolution phénotypique est dicté, de manière importante, par le point de départ ancestral.(Translated by Simon L. Ducatez).


La reconstrucción de la musculatura del ala en álcidos extintos no voladores (Pinguinus y Mancalla) revela una convergencia incompleta con los pingüinos (Spheniscidae) debido a sus distintos estados ancestralesA pesar del gran interés que tradicionalmente ha despertado la evolución convergente, los factores que limitan la evolución de fenotipos completamente convergentes siguen siendo poco conocidos. En las aves, la evolución del buceo mediante propulsión alar asociado a una pérdida de la capacidad de vuelo ha emergido como un ejemplo clásico de convergencia evolutiva, habiendo aparecido en linajes dispares que incluyen los pingüinos (Sphenisciformes) y los álcidos (Pan-Alcidae, Charadriiformes). Sin embargo, el conocimiento sobre la anatomía funcional de los álcidos no voladores es limitado, dado que dichos taxones están completamente extintos y su morfología está representada de modo prácticamente exclusivo por restos esqueléticos. En este trabajo, reconstruimos los ligamentos y los músculos del ala de dos álcidos extintos no voladores que representan dos transiciones independientes hacia la condición no voladora: Pinguinus impennis (un álcido del grupo corona) y Mancalla (un álcido del grupo troncal), con el objetivo de reevaluar el alcance de la convergencia evolutiva entre los distintos grupos de aves no voladoras que bucean mediante propulsión alar. A tal efecto, recolectamos información anatómica exhaustiva a partir de la disección de 12 especies existentes de caradriformes y 4 aequornitinas acuáticas, incluyendo un pingüino. Los resultados sugieren que las alas de ambos álcidos no voladores estaban caracterizadas por una mayor ventaja mecánica de los músculos elevadores/retractores del ala, y por una disminución de la movilidad de las articulaciones distales del ala. Ambas características son probablemente ventajosas para el buceo mediante propulsión alar y representan especializaciones funcionales similares a las de los pingüinos. Sin embargo, la configuración de los ligamentos y músculos individuales ligados a dichas especializaciones difiere marcadamente entre pingüinos y álcidos no voladores, siendo similar a la configuración en los respectivos parientes cercanos de cada grupo. En consecuencia, las alas de estas aves no voladoras que bucean mediante propulsión alar pueden ser descritas como convergentes si son consideradas como unidades funcionales generales, pero esta convergencia es incompleta en niveles inferiores de su organización anatómica. Esto es el resultado de la retención de las distintas condiciones presentes en los antepasados voladores de ambos grupos. Investigaciones detalladas como la presente pueden indicar que, incluso frente a requerimientos funcionales similares, el curso de la evolución fenotípica está fuertemente dictado por el punto de partida ancestral.(Translated by Juan Benito Moreno).

11.
Heart Rhythm ; 17(1): 133-141, 2020 01.
Artículo en Inglés | MEDLINE | ID: mdl-31369871

RESUMEN

BACKGROUND: Renal artery catheter ablation has been reported as a possible therapeutic option for drug-refractory ventricular arrhythmias (VAs) associated with structural heart diseases. OBJECTIVE: To further clarify its therapeutic background, we examined the relationship between electrical nerve stimulation (ENS)-induced blood pressure (BP) elevation and occurrence of VAs by using an acute canine model of renal artery ablation. METHODS: Using a decapolar electrode catheter, ENS was successively applied from the distal, mid, and proximal segments of the renal artery in 8 beagles. The same ENS was repeated after accomplishment of radiofrequency ablation at the ostial site of the renal artery by using an irrigation catheter. RESULTS: Before ablation, ENS increased BP from 140 ± 11/77 ± 11 to 167 ± 20/98 ± 16 mm Hg and heart rate from 100 ± 21 to 131±33 beats/min as well as induced VAs in 20 of the 45 ENS applications. Occurrence of VAs was associated with a greater magnitude of sympathetic nerve augmentation, and VAs were more frequently observed by ENS at the distal (67%) rather than mid/proximal segments of the renal artery (33%). Renal artery ablation was accomplished without any angiographic stenosis, and ENS-induced BP elevation, heart rate acceleration, and VAs occurrence were attenuated not only at the close segment (proximal) but also at the remote segments (mid/distal) of the renal artery. CONCLUSION: The renal autonomic nerves are considered as one of the therapeutic targets for suppression of frequent VAs because its activation has arrhythmogenic potential and induces premature ventricular beats.


Asunto(s)
Vías Autónomas/fisiopatología , Ablación por Catéter/métodos , Estimulación Eléctrica/métodos , Sistema de Conducción Cardíaco/cirugía , Arteria Renal/cirugía , Taquicardia Ventricular/cirugía , Animales , Modelos Animales de Enfermedad , Perros , Sistema de Conducción Cardíaco/fisiopatología , Taquicardia Ventricular/fisiopatología
12.
Evolution ; 72(12): 2632-2652, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30328113

RESUMEN

The evolutionary diversification of birds has been facilitated by specializations for various locomotor modes, with which the proportion of the limb skeleton is closely associated. However, recent studies have identified phylogenetic signals in this system, suggesting the presence of historical factors that have affected its evolutionary variability. In this study, to explore potential roles of ontogenetic integration in biasing the evolution in the avian limb skeleton, evolutionary diversification patterns in six avian families (Anatidae, Procellariidae, Ardeidae, Phalacrocoracidae, Laridae, and Alcidae) were examined and compared to the postnatal ontogenetic trajectories in those taxa, based on measurement of 2641 specimens and recently collected ontogenetic series, supplemented by published data. Morphometric analyses of lengths of six limb bones (humerus, ulna, carpometacarpus, femur, tibiotarsus, and tarsometatarsus) demonstrated that: (1) ontogenetic trajectories are diverse among families; (2) evolutionary diversification is significantly anisotropic; and, most importantly, (3) major axes of evolutionary diversification are correlated with clade-specific ontogenetic major axes in the shape space. These results imply that the evolutionary variability of the avian limbs has been biased along the clade-specific ontogenetic trajectories. It may explain peculiar diversification patterns characteristic to some avian groups, including the long-leggedness in Ardeidae and tendency for flightlessness in Anatidae.


Asunto(s)
Evolución Biológica , Aves/crecimiento & desarrollo , Aves/genética , Miembro Posterior/crecimiento & desarrollo , Alas de Animales/crecimiento & desarrollo , Animales , Aves/clasificación , Vuelo Animal , Variación Genética , Modelos Biológicos
13.
Anat Rec (Hoboken) ; 301(6): 1026-1045, 2018 06.
Artículo en Inglés | MEDLINE | ID: mdl-29195009

RESUMEN

Despite its importance in various disciplines, a general method to assess ontogenetic ages of skeletal and fossil specimens has been lacking for birds. Although the textural ageing method was formulated to assess relative ontogenetic ages of specimens from inspection of bone surface textures, the exact correspondence of surface textures to ontogenetic stages has not yet been clear. In this study, bone surface textures of six major limb bones (humerus, ulna, carpometacarpus, femur, tibiotarsus, and tarsometatarsus) were described in postnatal ontogenies of four species of modern birds (Calonectris leucomelas, Phalacrocorax capillatus, Larus crassirostris, and Cerorhinca monocerata) from 14 to 28 individuals of known ontogenetic stages for each species. Consistently with the previous postulation, it was found that bones of chicks were characterized by rough surface textures with numerous grooves/depressions that host minute foramina. Bones of fledglings/juveniles, which are generally as large as those of adults but more slender, were characterized by the occasional presence of depressions and foramina. Histological observations confirmed that these rough surface textures were underlain by fibrolamellar bone tissue which is associated with active periosteal ossification. These results indicate that the smooth surface texture in adults is formed after the cessation of circumferential bone growth, which probably takes place between fledging and the attainment of sexual maturity. The available evidence suggests that the textural ageing is probably applicable to the entire Neognathae, a clade containing most crown-group birds. Anat Rec, 301:1026-1045, 2018. © 2017 Wiley Periodicals, Inc.


Asunto(s)
Envejecimiento/fisiología , Aves/anatomía & histología , Huesos/anatomía & histología , Animales
14.
Water Res ; 145: 1-11, 2018 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-30103048

RESUMEN

Occurrence of residual endotoxin activity (ET) in dialysis water and also tap water as its source is a matter of great concern to medical professionals conducting dialysis therapy at healthcare facilities (HCFs). The present study was performed to determine the occurrence and fate of the ET at selected Japanese drinking water purification plants and HCFs between 2014 and 2016. Chemical coagulation and sedimentation, rapid sand filtration, and membrane filtration were highly effective to decrease both ET dissolved in water (free-ET) and ET bound to cells/particles (bound-ET). Moderate decreases in bound-ET and limited decreases in free-ET were observed by chlorination and ozonation. Bacterial activated carbon filtration was a major cause of significant increases in endotoxin activity during the course of drinking water purification process. Levels of residual ET in water supplied to HCFs were strongly affected by their source waters and the configurations of water purification processes served. Microbial regrowth on the premises, from water tanks to faucets at HCFs could also contribute to ET increases in tap water.


Asunto(s)
Agua Potable , Contaminantes Químicos del Agua , Purificación del Agua , Endotoxinas , Filtración , Japón , Diálisis Renal
15.
J Chromatogr A ; 944(1-2): 41-59, 2002 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-11831763

RESUMEN

Synthetic adsorbents with fine particle sizes (15-30 microm) were manufactured. These adsorbents are made of poly(styrenedivinylbenzene) and polymethacrylate, and have the same chemical structure as analytical- (5-10 microm) or industrial- (200-600 microm) grade synthetic adsorbents. Both of them have very similar porous structure to those of analytical or industrial sizes, so that they can adsorb compounds of various molecular masses. Chromatographic separation characteristics of newly manufactured fine-particle grades of synthetic adsorbents were evaluated and compared to those of analytical or industrial adsorbents. Reasonable dependency of separation performance on particle size of synthetic adsorbents was obtained. Hydraulic properties of fine-grade adsorbents had also been measured in view of column operations. Furthermore, scalability and applicability of these adsorbents for preparative-scale chromatographic separation of bioactive compounds was evaluated. Separation of soybean isoflavones and tea catechin derivatives had revealed that fine-grade synthetic adsorbents could be well applied with scalability under the same elution conditions used for analytical use. Scalability up to a 22400-fold loading amount was achieved from a small column packed with analytical-grade adsorbent used for method development to a scale-up preparative column packed with fine-grade adsorbent used for preparative purification. These results showed the usefulness of the fine-grade synthetic adsorbents for more precise purification of bioactive compounds, including pharmaceuticals and functional food additives with higher recovery.


Asunto(s)
Cromatografía Liquida/instrumentación , Adsorción , Catequina/aislamiento & purificación , Isoflavonas/aislamiento & purificación , Tamaño de la Partícula , Glycine max/química , Espectrofotometría Ultravioleta , Té/química
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