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1.
Biol Lett ; 17(4): 20200729, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33878275

RESUMEN

We explored fluctuating asymmetry (FA) and morphological integration (MI) in the skull of the small, highly inbred and divergent Apennine bear (Ursus arctos marsicanus), to explore its uniqueness and investigate any potential effects of inbreeding depression. We used 3D geometric morphometrics contrasting Apennine bears with other two large outbred bear populations from Scandinavia and Kamchatka as controls. Shape divergence and variability were explored by a principal component analysis on aligned coordinates of 39 landmarks. Procrustes ANOVA, morphological disparity and the global integration index were used to explore FA, shape variance and MI. By remarking Apennine bears as a highly divergent phenotype, we recorded the highest FA and deviation from self-similarity compared with the other two control populations. We conclude that Apennine bears are likely facing developmental instability as a consequence of inbreeding depression, whereas the divergent trait covariance pattern may represent a potential source of evolutionary novelties. We discuss the implications for the conservation and management of this imperiled taxon.


Asunto(s)
Ursidae , Animales , Fenotipo , Cráneo , Ursidae/genética
2.
J Pest Sci (2004) ; 89: 45-57, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26924956

RESUMEN

The bean fly (Ophiomyia spp.) is considered the most economically damaging field insect pest of common beans in Uganda. Despite the use of existing pest management approaches, reported damage has remained high. Forty-eight traditional and improved common bean varieties currently grown in farmers' fields were evaluated for resistance against bean fly. Data on bean fly incidence, severity and root damage from bean stem maggot were collected. Generalized linear mixed model (GLMM) revealed significant resistance to bean fly in the Ugandan traditional varieties. A popular resistant traditional variety and a popular susceptible commercial variety were selected from the 48 varieties and evaluated in pure and mixed stands. The incidence of bean fly infestation on both varieties in mixtures with different arrangements (systematic random versus rows), and different proportions within each of the two arrangements, was measured and analysed using GLMMs. The proportion of resistant varieties in a mixture and the arrangement type significantly decreased bean fly damage compared to pure stands, with the highest decrease in damage registered in the systematic random mixture with at least 50 % of resistant variety. The highest reduction in root damage, obvious 21 days after planting, was found in systematic random mixtures with at least 50 % of the resistant variety. Small holder farmers in East Africa and elsewhere in the world have local preferences for growing bean varieties in genetic mixtures. These mixtures can be enhanced by the use of resistant varieties in the mixtures to reduce bean fly damage on susceptible popular varieties.

3.
Clin Pharmacol Ther ; 97(4): 404-10, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25670256

RESUMEN

The pivotal clinical trial to support the indication of liver transplantation for everolimus was based on a noninferiority trial design. The unique trial design made it impossible to estimate the noninferiority margin at the design stage. Even though the trial was conducted based on a noninferiority margin of 12% for the primary efficacy endpoint, the lack of consensus on this margin made the efficacy results difficult to interpret. A novel pharmacometric approach was applied to derive a new margin. Even though it was smaller than 12%, the new margin was large enough so that the observed efficacy results became interpretable. This novel analysis was an important contributor to the "totality of evidence" approach that led to the approval of everolimus for the new indication. This approval represents the approval of a new drug in more than 10 years for the indication of liver transplantation.


Asunto(s)
Relación Dosis-Respuesta a Droga , Ensayos Clínicos Controlados Aleatorios como Asunto , Proyectos de Investigación , Adulto , Anciano , Interpretación Estadística de Datos , Quimioterapia Combinada , Everolimus , Femenino , Rechazo de Injerto/prevención & control , Humanos , Inmunosupresores/uso terapéutico , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Reproducibilidad de los Resultados , Sirolimus/análogos & derivados , Sirolimus/uso terapéutico , Tacrolimus/uso terapéutico , Adulto Joven
4.
Phys Rev Lett ; 112(4): 041601, 2014 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-24580437

RESUMEN

The nucleon structure function F2(N) computed in a holographic framework can be used to describe nuclear deep inelastic scattering effects provided that a rescaling of the Q2 momentum and of the IR hard-wall parameter z0 is made. The ratios RA=F2(A)/F2(N) can be obtained in terms of a single rescaling parameter λA for each nucleus. The resulting ratios agree with the experiment in a wide range of the shadowing region.

5.
J Morphol ; 273(7): 696-711, 2012 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-22419178

RESUMEN

The shape and mechanical performance in Talpidae humeri were studied by means of Geometric Morphometrics and Finite Element Analysis, including both extinct and extant taxa. The aim of this study was to test whether the ability to dig, quantified by humerus mechanical performance, was characterized by convergent or parallel adaptations in different clades of complex tunnel digger within Talpidae, that is, Talpinae+Condylura (monophyletic) and some complex tunnel diggers not belonging to this clade. Our results suggest that the pattern underlying Talpidae humerus evolution is evolutionary parallelism. However, this insight changed to true convergence when we tested an alternative phylogeny based on molecular data, with Condylura moved to a more basal phylogenetic position. Shape and performance analyses, as well as specific comparative methods, provided strong evidence that the ability to dig complex tunnels reached a functional optimum in distantly related taxa. This was also confirmed by the lower phenotypic variance in complex tunnel digger taxa, compared to non-complex tunnel diggers. Evolutionary rates of phenotypic change showed a smooth deceleration in correspondence with the most recent common ancestor of the Talpinae+Condylura clade.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Húmero/anatomía & histología , Mamíferos/anatomía & histología , Aclimatación , Animales , Fenómenos Biomecánicos , Clasificación , Análisis de Elementos Finitos , Húmero/fisiología , Mamíferos/clasificación , Topos/anatomía & histología , Topos/fisiología , Fenotipo , Filogenia
6.
Clin Pharmacol Ther ; 90(2): 217-20, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21772300

RESUMEN

This workshop was organized by the US Food and Drug Administration (FDA) Office of Clinical Pharmacology Review Team supporting the Division of Special Pathogen and Transplant Products in the Center for Drug Evaluation and Research. The main goal of the workshop was to enhance the knowledge base regarding biomarkers in solid-organ transplantation via presentation and discussion of scientific findings.


Asunto(s)
Biomarcadores Farmacológicos/metabolismo , Biomarcadores/metabolismo , Trasplante de Órganos/métodos , United States Food and Drug Administration , Educación , Humanos , Inmunosupresores/uso terapéutico , Estados Unidos
7.
Clin Pharmacol Ther ; 88(1): 115-9, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20505665

RESUMEN

The purpose of this article is to report the exposure-response (E-R) relationship of posaconazole oral suspension (POS) for prophylaxis against invasive fungal infections (IFIs), on the basis of the US Food and Drug Administration (FDA) clinical pharmacology review of two randomized, active-controlled clinical studies. Posaconazole average steady state plasma concentrations (C(avg)) ranged from 22 to 3,650 ng/ml after administration of POS 200 mg three times daily (t.i.d.). In a double-blind, randomized clinical trial, the quartile ranges of C(avg) with midpoint values of 289, 736, 1,239, and 2,607 ng/ml had clinical failure rates of 44, 21, 18, and 18%, respectively, indicating an inverse association between C(avg) and clinical failure rate. There were no significant relationships between C(avg) and posaconazole-related major adverse events. Determining posaconazole concentrations in plasma will aid in assessing the need for either POS dose adjustment (e.g., increasing the POS dose) or switching to another systemic antifungal drug, thereby improving the effectiveness of prophylaxis against IFIs.


Asunto(s)
Antifúngicos/administración & dosificación , Antifúngicos/uso terapéutico , Micosis/prevención & control , Triazoles/administración & dosificación , Triazoles/uso terapéutico , Antifúngicos/farmacocinética , Antineoplásicos/efectos adversos , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Enfermedad Injerto contra Huésped/complicaciones , Humanos , Neutropenia/inducido químicamente , Neutropenia/complicaciones , Trasplante de Células Madre , Resultado del Tratamiento , Triazoles/farmacocinética
8.
Mol Phylogenet Evol ; 55(2): 372-80, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20138223

RESUMEN

The range of the genus Talpa covers almost all Europe up to Western Asia. This genus has never been the object of comprehensive systematic studies using molecular and genetic techniques, such that the evolutionary relationships among species remain unclear. Talpa shows high levels of endemism, and the influence of past glaciation cycles on the distribution pattern of several species has been hypothesized. In this work, we assessed the molecular systematics of the genus using the mitochondrial gene cytochrome b from eight of the nine extant species of Talpa moles. Furthermore, molecular clock estimations were used to hypothesize a biogeographic scenario in concordance with fossil data. Results suggest a monophyletic origin of the genus and a common ancestor for the western European moles T. europaea, T. caeca, T. romana and T. occidentalis. The eastern species T. altaica and T. caucasica are basally divergent. The estimated ages of divergence among lineages are in accordance with a Miocene origin of the extant moles. The genus likely originated in Asia, spreading into Europe during the Pliocene. The evolution of moles appears to have been driven by changes in moisture levels that influenced extinction and speciation events during the Miocene and the Pliocene. Pleistocene climatic oscillations likely caused the range shrinkages and expansions that led to the current distribution pattern of most Talpa species.


Asunto(s)
Evolución Molecular , Topos/genética , Filogenia , Animales , Teorema de Bayes , Citocromos b/genética , ADN Mitocondrial/genética , Geografía , Funciones de Verosimilitud , Modelos Genéticos , Topos/clasificación , Análisis de Secuencia de ADN
9.
Appl Radiat Isot ; 67(7-8 Suppl): S292-5, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19406649

RESUMEN

The boron neutron capture therapy is mainly suited in the treatment of some tumor kinds which revealed ineffective to the traditional radiotherapy. In order to take advantage of such a therapeutic modality in hospital environments, neutron beams of suitable energy and flux levels provided by compact size facilities are needed. The advantages and drawbacks of several neutron beams are here analysed in terms of therapeutic gains. In detail the GEANT-3/MICAP simulations show that high tumor control probability, with sub-lethal dose at healthy tissues, can be achieved by using neutron beams of few keV energy having a flux of about 10(9) neutrons/(cm(2)s). To produce such a neutron beam, the feasibility of a proton accelerator is investigated. In particular an appropriate choice of the radiofrequency parameters (modulation, efficiency of acceleration, phase shift, etc.) allows the development of relatively compact accelerators, having a proton beam current of 30 mA and an energy of 2 MeV, which could eventually lead to setting up of hospital-based neutron facilities.


Asunto(s)
Terapia por Captura de Neutrón de Boro/instrumentación , Neutrones/uso terapéutico , Aceleradores de Partículas , Fenómenos Biofísicos , Neoplasias Encefálicas/radioterapia , Diseño de Equipo , Neutrones Rápidos/uso terapéutico , Humanos , Método de Montecarlo , Fantasmas de Imagen/estadística & datos numéricos , Protones
10.
Phys Med Biol ; 45(1): 49-58, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10661582

RESUMEN

The optimal neutron energy for the treatment of deep-seated tumours using boron neutron capture therapy is studied by analysing various figures of merit. In particular, analysis of the therapeutic gain as a function of the neutron energy indicates that, with the currently available 10B carriers, the most useful neutrons for the treatment of deep-seated tumours, in particular glioblastoma multiforme, are those with an energy of a few keV. Based on the results of the simulations, a method is presented which allows us to evaluate the quality of epithermal neutron beams of known energy spectrum, thus allowing us to compare different neutron-producing reactions and beam-shaping assembly configurations used for accelerator-based neutron sources.


Asunto(s)
Terapia por Captura de Neutrón de Boro , Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Boro , Simulación por Computador , Humanos , Método de Montecarlo , Neutrones
11.
Implant Dent ; 9(3): 219-25, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-11307408

RESUMEN

The aim of the study was to evaluate the mechanical performance and the structure of neoformed bone around hydroxyapatite-coated titanium fixtures according to guided bone regeneration techniques. Ten hydroxyapatite-coated titanium fixtures were inserted in the femurs of five rabbits, in which a cortical defect was created and after the insertion of the fixture, covered with a resorbable membrane obtained from bovine Achilles tendon collagen Type I (A implant). In the same femur, a second fixture was inserted in similar cavities without application of the membrane (B implant). After 60 days, the animals were sacrificed, and block sections of the femoral bone containing the implants were embedded in polymethylmetacrylate and subjected to tensile shear-stress at break testing. After the detachment of the implants from the bone, their surfaces were examined with a scanning electron microscope. Tensile shear-stress values for A and B implant specimens were comparable to some extent, but the former had a lower performance. In this regard, scanning electron microscope observations showed that the neoformed cortical bone present cervically around implant A was much thicker than around implant B.


Asunto(s)
Regeneración Ósea , Colágeno , Fémur/cirugía , Regeneración Tisular Guiada Periodontal/instrumentación , Membranas Artificiales , Implantes Absorbibles , Animales , Materiales Biocompatibles , Bovinos , Materiales Biocompatibles Revestidos , Implantes Dentales , Durapatita , Femenino , Fémur/patología , Fémur/fisiopatología , Masculino , Microscopía Electrónica de Rastreo , Modelos Animales , Osteogénesis/fisiología , Adhesión en Plástico , Polimetil Metacrilato , Conejos , Estrés Mecánico , Propiedades de Superficie , Resistencia a la Tracción , Titanio
12.
Pediatr Neurol ; 15(4): 337-9, 1996 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-8972535

RESUMEN

Progressive encephalopathy with edema, hypsarrhythmia, and optic atrophy syndrome is a recently described rare disorder of infantile regression, intractable seizures, and cerebellar atrophy that occurs almost exclusively in the Finnish population. We report the first North American child with this condition.


Asunto(s)
Edema Encefálico/genética , Cerebelo/patología , Atrofia Óptica/genética , Espasmos Infantiles/genética , Atrofia , Preescolar , Electroencefalografía , Potenciales Evocados/fisiología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Imagen por Resonancia Magnética , Examen Neurológico , Síndrome
13.
Phys Rev D Part Fields ; 54(7): 4622-4628, 1996 Oct 01.
Artículo en Inglés | MEDLINE | ID: mdl-10021143
14.
Phys Rev D Part Fields ; 54(1): 1212-1214, 1996 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-10020589
15.
Phys Rev D Part Fields ; 53(7): 3672-3686, 1996 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-10020364
16.
Phys Rev D Part Fields ; 52(11): 6422-6434, 1995 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-10019183
17.
Clin Pharmacol Ther ; 58(3): 310-5, 1995 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-7554704

RESUMEN

A double-blind placebo-controlled study was conducted in healthy men to determine the effect of coadministration of azithromycin on the pharmacodynamics and pharmacokinetics of terfenadine. Administration of 500 mg azithromycin for 1 day and 250 mg on 4 subsequent days did not affect the pharmacokinetics of the pharmacologically active terfenadine carboxylate metabolite when 60 mg terfenadine was given twice daily for 12 days, starting 7 days before azithromycin administration. Terfenadine alone resulted in a 0.010 msec increase in the rate-corrected QT interval (QTc), but the incremental effects of azithromycin and placebo on QTc in volunteers receiving terfenadine were not statistically different. It is concluded that the potentially life-threatening disorders that have been attributed to a pharmacokinetic interaction between macrolide antibiotics and terfenadine are unlikely to take place in patients treated simultaneously with azithromycin and terfenadine.


Asunto(s)
Antibacterianos/farmacología , Azitromicina/farmacología , Antagonistas de los Receptores Histamínicos H1/farmacología , Terfenadina/farmacología , Adulto , Antibacterianos/efectos adversos , Antibacterianos/farmacocinética , Azitromicina/efectos adversos , Azitromicina/farmacocinética , Método Doble Ciego , Interacciones Farmacológicas , Electrocardiografía/efectos de los fármacos , Antagonistas de los Receptores Histamínicos H1/efectos adversos , Antagonistas de los Receptores Histamínicos H1/farmacocinética , Humanos , Masculino , Placebos , Terfenadina/efectos adversos , Terfenadina/farmacocinética
19.
Phys Rev D Part Fields ; 49(1): 238-246, 1994 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-10016758
20.
Implant Dent ; 2(2): 101-5, 1993.
Artículo en Inglés | MEDLINE | ID: mdl-8242012

RESUMEN

Artificial cross-shaped intrabony defects were created in the mandibles of 12 rabbits and the cavities covered with Type I highly cross-linked resorbable collagen membranes for 30 days. Similar cavities were prepared in three control animals and left uncovered for the same time period. Morphological and analytical data were obtained by means of light microscopy, scanning electron microscopy, and x-ray energy-dispersive spectrometry. After the experimental period, the membrane covered cavities were completely filled with regenerated bone. In the control specimens, the artificial cavities were occupied by fibrous connective tissue.


Asunto(s)
Regeneración Ósea , Colágeno , Regeneración Tisular Dirigida , Animales , Biodegradación Ambiental , Estudios de Evaluación como Asunto , Femenino , Masculino , Mandíbula , Membranas , Microscopía Electrónica de Rastreo , Proyectos Piloto , Conejos , Cicatrización de Heridas
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