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1.
Ecology ; 99(10): 2405, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-29999519

RESUMEN

Cooperative breeding decreases the direct reproductive output of subordinate individuals, but cooperation can be evolutionarily favored when there are challenges or constraints to breeding independently. Environmental factors, including temperature, precipitation, latitude, high seasonality, and environmental harshness have been hypothesized to correlate with the presence of cooperative breeding. However, to test the relationship between cooperation and ecological constraints requires comparative data on the frequency and variation of cooperative breeding across differing environments, ideally replicated across multiple species. Paper wasps are primitively social species, forming colonies composed of reproductively active dominants and foraging subordinates. Adult female wasps, referred to as foundresses, initiate new colonies. Nests can be formed by a single solitary foundress (noncooperative) or by multiple foundress associations (cooperative). Cooperative behavior varies within and among species, making paper wasps species well suited to disentangling ecological correlates of variation in cooperative behavior. This data set reports the frequency and extent of cooperative nest founding for 87 paper wasp species. Data were assembled from more than 170 published sources, previously unpublished field observations, and photographs contributed by citizen scientists to online natural history repositories. The data set includes 25,872 nest observations and reports the cooperative behavioral decisions for 45,297 foundresses. Species names were updated to reflect modern taxonomic revisions. The type of substrate on which the nest was built is also included, when available. A smaller population-level version of this data set found that the presence or absence of cooperative nesting in paper wasps was correlated with temperature stability and environmental harshness, but these variables did not predict the extent of cooperation within species. This expanded data set contains details about individual nests and further increases the power to address the relationship between the environment and the presence and extent of cooperative breeding. Beyond the ecological drivers of cooperation, these high-resolution data will be useful for future studies examining the evolutionary consequences of variation in social behavior. This data set may be used for research or educational purposes provided that this data paper is cited.

2.
J Small Anim Pract ; 59(2): 98-105, 2018 02.
Artículo en Inglés | MEDLINE | ID: mdl-29095498

RESUMEN

OBJECTIVES: To describe the placement of self-inflating tissue expanders and clinical outcomes in 12 consecutive cases of reconstruction of distal cutaneous limb defects in dogs. MATERIALS AND METHODS: Cases of distal cutaneous limb defect were divided into three groups based on the location of the placement of the self-inflating tissue expanders: Group A (n=4): on, or proximal to, the elbow and stifle; Group B (n=4): distal to the elbow or stifle and proximal to the carpus or tarsus; and Group C (n=4): distal to the carpus or tarsus. Owner satisfaction and clinical outcome were documented. RESULTS: Thirteen cases were originally included, but one was excluded because of incomplete follow-up. In one case, the self-inflating tissue expanders were removed before expansion started. A mean of five expanders were implanted per dog (range 2 to 9). Devices were removed after a mean of 24 days (range 13 to 42 days). Primary closure was achieved in eight of 11 cases, including all cases from Group A and 75% and 33% of cases from Groups B and C, respectively. All incompletely reconstructed defects or areas of wound dehiscence healed by second intention. Eight of 12 owners were satisfied. CLINICAL SIGNIFICANCE: Self-inflating tissue expanders can be used as an alternative for the reconstruction of limb defects in dogs in which direct primary closure would otherwise not be achievable. Defects below the carpus and tarsus are more challenging to treat with this method.


Asunto(s)
Extremidades/cirugía , Procedimientos de Cirugía Plástica/veterinaria , Dispositivos de Expansión Tisular/veterinaria , Animales , Perros , Hidrogeles , Estudios Prospectivos , Expansión de Tejido/métodos , Expansión de Tejido/veterinaria , Resultado del Tratamiento , Heridas y Lesiones/cirugía , Heridas y Lesiones/veterinaria
3.
Rev Sci Instrum ; 88(3): 033706, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28372445

RESUMEN

An experimental technique for the estimation of the temporal-averaged vapour volume fraction within high-speed cavitating flow orifices is presented. The scientific instrument is designed to employ X-ray micro computed tomography (microCT) as a quantitative 3D measuring technique applied to custom designed, large-scale, orifice-type flow channels made from Polyether-ether-ketone (PEEK). The attenuation of the ionising electromagnetic radiation by the fluid under examination depends on its local density; the transmitted radiation through the cavitation volume is compared to the incident radiation, and combination of radiographies from sufficient number of angles leads to the reconstruction of attenuation coefficients versus the spatial position. This results to a 3D volume fraction distribution measurement of the developing multiphase flow. The experimental results obtained are compared against the high speed shadowgraph visualisation images obtained in an optically transparent nozzle with identical injection geometry; comparison between the temporal mean image and the microCT reconstruction shows excellent agreement. At the same time, the real 3D internal channel geometry (possibly eroded) has been measured and compared to the nominal manufacturing CAD drawing of the test nozzle.

4.
Vox Sang ; 111(4): 391-398, 2016 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-27509167

RESUMEN

BACKGROUND AND OBJECTIVES: Patient Blood Management (PBM) in Europe is a working group of the European Blood Alliance with the initial objective to identify the starting position of the participating hospitals regarding PBM for benchmarking purposes, and to derive good practices in PBM from the experience and expertise in the participating teams with the further aim of implementing and strengthening these practices in the participating hospitals. METHODS: We conducted two surveys in seven university hospitals in Europe: Survey on top indications for red blood cell use regarding usage of red blood cells during 1 week and Survey on PBM organization and activities. RESULTS: A total of 3320 units of red blood cells were transfused in 1 week at the seven hospitals. Overall, 61% of red cell units were transfused to medical patients and 36% to surgical patients, although there was much variation between hospitals. The organization and activities of PBM in the seven hospitals were variable, but there was a common focus on optimizing the treatment of bleeding patients, monitoring the use of blood components and treatment of preoperative anaemia. CONCLUSION: Although the seven hospitals provide a similar range of clinical services, there was variation in transfusion rates between them. Further, there was variable implementation of PBM activities and monitoring of transfusion practice. These findings provide a baseline to develop joint action plans to further implement and strengthen PBM across a number of hospitals in Europe.


Asunto(s)
Hospitales Universitarios , Anemia/terapia , Conservación de la Sangre , Transfusión Sanguínea/normas , Transfusión Sanguínea/estadística & datos numéricos , Europa (Continente) , Encuestas de Atención de la Salud , Humanos
5.
Neuroimage ; 115: 224-34, 2015 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-25963734

RESUMEN

In this study we introduce the regional flux analysis, a novel approach to deformation based morphometry based on the Helmholtz decomposition of deformations parameterized by stationary velocity fields. We use the scalar pressure map associated to the irrotational component of the deformation to discover the critical regions of volume change. These regions are used to consistently quantify the associated measure of volume change by the probabilistic integration of the flux of the longitudinal deformations across the boundaries. The presented framework unifies voxel-based and regional approaches, and robustly describes the volume changes at both group-wise and subject-specific level as a spatial process governed by consistently defined regions. Our experiments on the large cohorts of the ADNI dataset show that the regional flux analysis is a powerful and flexible instrument for the study of Alzheimer's disease in a wide range of scenarios: cross-sectional deformation based morphometry, longitudinal discovery and quantification of group-wise volume changes, and statistically powered and robust quantification of hippocampal and ventricular atrophy.


Asunto(s)
Enfermedad de Alzheimer/patología , Encéfalo/patología , Algoritmos , Anatomía Transversal , Atrofia/patología , Ventrículos Cerebrales/patología , Bases de Datos Factuales , Progresión de la Enfermedad , Hipocampo/patología , Humanos , Procesamiento de Imagen Asistido por Computador
6.
Rev Sci Instrum ; 86(2): 023708, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25725853

RESUMEN

An experimental study about the anisotropic wetting behavior of a surface patterned with parallel grooves is presented as an application example of a novel technique for investigation of complete and partial anisotropic wetting on structured surface by X-ray microtomography. Shape of glycerin droplets on such surface is investigated by X-ray micro computed tomography (microCT) acting as a non-intrusive, full volume 3D microscope with micrometric spatial resolution. The reconstructed drop volumes enable to estimate the exact volumes of the drops, their base contours, and 3D static contact angles, based on true cross-sections of the drop-surface couple. Droplet base contours are compared to approximate geometrical contour shapes proposed in the literature. Contact angles along slices parallel and perpendicular to the grooves direction are compared with each other. The effect of the sessile drop volume on the wetting behavior is discussed. The proposed technique, which is applicable for any structured surface, enables the direct measure of Wenzel ratio based on the microCT scan in the wetted region usually inapproachable by any others. Comparisons with simplified models are presented and congruence of results with respect to the minimum resolution needed is evaluated and commented.

7.
QJM ; 108(4): 299-306, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25239762

RESUMEN

AIM: To conduct a network meta-analysis (NMA) to determine the comparative efficacy, as measured by sustained virological response (SVR), between boceprevir (BOC), telaprevir (TEL), faldaprevir (FAL), simeprevir (SIM) and sofosbuvir (SOF) in combination with peginterferon-ribavirin (PR) against a control of PR. DESIGN: A literature search was conducted to identify randomized controlled trials (RCTs) including adult patients with hepatitis C virus genotype 1 who were naive to any prior therapy. RCTs assessing standard duration therapy (SDT) or response-guided therapy (RGT) BOC, TEL, FAL, SIM or SOF in combination with PR against a control of PR were eligible for inclusion. All RCTs must have provided SVR at either 12 or 24 weeks post-therapy cessation. RESULTS: We included nine RCTs. All direct-acting antivirals (DAAs) were found to perform better than PR. Additionally, SDT FAL was found to be better than the 240 mg RGT FAL regimen with the PR lead-in. A sensitivity analysis excluding RCTs with only SVR at 12 weeks was consistent with the results of the primary analysis. A sensitivity analysis removing an RCT assessing SIM that reported SVR of >60% in the PR control group additionally found that RGT SIM was superior to the 240 mg RGT FAL regimen with the PR lead-in. DISCUSSION: Our analyses indicate that SDT and RGT regimens of DAAs plus PR do not differ greatly in terms of SVR among treatment-naive hepatitis C genotype 1 patients. More advanced Bayesian network meta-analyses are likely needed to incorporate a comprehensive evidence base, expanding beyond randomized clinical trials.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis C Crónica/tratamiento farmacológico , Teorema de Bayes , Quimioterapia Combinada , Genotipo , Hepacivirus/genética , Humanos , Interferón alfa-2 , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Proteínas Recombinantes/uso terapéutico , Ribavirina/uso terapéutico
8.
Animal ; 9(4): 728-34, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25500004

RESUMEN

One of the consequences of intense genetic selection for growth of poultry is the recent appearance of abnormalities in chicken breast muscles, such as white striping (characterised by superficial white striations) and wooden breast (characterised by pale and bulged areas with substantial hardness). The aim of this study was to evaluate the quality traits of chicken fillets affected by white striping and wooden breast abnormalities. In two replications, 192 fillets were divided into the following four classes: normal (n=48; absence of any visual defects), white striping (n=48, presence of white striations), wooden breast (n=48; diffusely presence of hardened areas) and white striping/wooden breast (n=48; fillets affected by both abnormalities). Morphology, raw meat texture and technological properties were assessed in both unprocessed (pH, colour, drip loss, cooking loss and cooked meat shear force) and marinated meat (marinade uptake, purge loss, cooking loss and cooked meat shear force). Fillets affected by white striping, wooden breast or both abnormalities exhibited higher breast weights compared with normal fillets (305.5, 298.7, 318.3 and 244.7 g, respectively; P<0.001). Wooden breast, either alone or in combination with white striping, was associated with a significant (P<0.001) increase of fillet thickness in the caudal area and raw meat hardness compared with both normal and the white striping abnormality, for which there was no difference. Overall, the occurrence of the individual and combined white striping and wooden breast abnormalities resulted in substantial reduction in the quality of breast meat, although these abnormalities are associated with distinct characteristics. Wooden breast fillets showed lower marinade uptake and higher cooking losses than white-striped fillets for both unprocessed and marinated meats. On the other hand, white-striped fillets showed a moderate decline in marinade and cooking yield. Fillets affected by both abnormalities had the highest (P<0.001) ultimate pH values. In contrast, the effects on colour of raw and cooked meat, drip loss, purge loss and cooked meat shear force were negligible or relatively low and of little practical importance. Thus, the presence of white striping and wooden breast abnormalities impair not only breast meat appearance but also the quality of both raw and marinated meats mainly by reducing water holding/binding abilities.


Asunto(s)
Culinaria/métodos , Carne/análisis , Carne/normas , Animales , Pollos/fisiología , Color
9.
Cell Death Differ ; 21(2): 234-46, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24037089

RESUMEN

We previously reported that STAT1 expression is frequently abrogated in human estrogen receptor-α-positive (ERα(+)) breast cancers and mice lacking STAT1 spontaneously develop ERα(+) mammary tumors. However, the precise mechanism by which STAT1 suppresses mammary gland tumorigenesis has not been fully elucidated. Here we show that STAT1-deficient mammary epithelial cells (MECs) display persistent prolactin receptor (PrlR) signaling, resulting in activation of JAK2, STAT3 and STAT5A/5B, expansion of CD61(+) luminal progenitor cells and development of ERα(+) mammary tumors. A failure to upregulate SOCS1, a STAT1-induced inhibitor of JAK2, leads to unopposed oncogenic PrlR signaling in STAT1(-/-) MECs. Prophylactic use of a pharmacological JAK2 inhibitor restrains the proportion of luminal progenitors and prevents disease induction. Systemic inhibition of activated JAK2 induces tumor cell death and produces therapeutic regression of pre-existing endocrine-sensitive and refractory mammary tumors. Thus, STAT1 suppresses tumor formation in mammary glands by preventing the natural developmental function of a growth factor signaling pathway from becoming pro-oncogenic. In addition, targeted inhibition of JAK2 may have significant therapeutic potential in controlling ERα(+) breast cancer in humans.


Asunto(s)
Receptor alfa de Estrógeno/metabolismo , Janus Quinasa 2/metabolismo , Neoplasias Mamarias Animales/metabolismo , Células Madre Neoplásicas/metabolismo , Factor de Transcripción STAT1/metabolismo , Proteínas Supresoras de la Señalización de Citocinas/metabolismo , Animales , Supervivencia Celular/efectos de los fármacos , Células Cultivadas , Femenino , Compuestos Heterocíclicos con 3 Anillos/farmacología , Janus Quinasa 2/antagonistas & inhibidores , Neoplasias Mamarias Animales/tratamiento farmacológico , Neoplasias Mamarias Animales/genética , Ratones , Células Madre Neoplásicas/efectos de los fármacos , Células Madre Neoplásicas/patología , Factor de Transcripción STAT1/deficiencia , Transducción de Señal/efectos de los fármacos , Proteína 1 Supresora de la Señalización de Citocinas
10.
Neurogastroenterol Motil ; 25(10): e669-79, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23859028

RESUMEN

BACKGROUND: Over the last 15 years, many studies demonstrated the myogenic regenerative potential of bone marrow mesenchymal stem cells (BM-MSC), making them an attractive tool for the regeneration of damaged tissues. In this study, we have developed an animal model of esophagogastric myotomy (MY) aimed at determining the role of autologous MSC in the regeneration of the lower esophageal sphincter (LES) after surgery. METHODS: Syngeneic BM-MSC were locally injected at the site of MY. Histological and functional analysis were performed to evaluate muscle regeneration, contractive capacity, and the presence of green fluorescent protein-positive BM-MSC (BM-MSC-GFP(+) ) in the damaged area at different time points from implantation. KEY RESULTS: Treatment with syngeneic BM-MSC improved muscle regeneration and increased contractile function of damaged LES. Transplanted BM-MSC-GFP(+) remained on site up to 30 days post injection. Immunohistochemical analysis demonstrated that MSC maintain their phenotype and no differentiation toward smooth or striated muscle was shown at any time point. CONCLUSIONS & INFERENCES: Our data support the use of autologous BM-MSC to both improve sphincter regeneration of LES and to control the gastro-esophageal reflux after MY.


Asunto(s)
Esfínter Esofágico Inferior/fisiología , Trasplante de Células Madre Mesenquimatosas/métodos , Regeneración , Animales , Trasplante de Médula Ósea/métodos , Modelos Animales de Enfermedad , Unión Esofagogástrica/lesiones , Inmunohistoquímica , Masculino , Músculo Liso/lesiones , Ratas , Ratas Endogámicas Lew
11.
Neuroimage ; 81: 470-483, 2013 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-23685032

RESUMEN

Non-linear registration is a key instrument for computational anatomy to study the morphology of organs and tissues. However, in order to be an effective instrument for the clinical practice, registration algorithms must be computationally efficient, accurate and most importantly robust to the multiple biases affecting medical images. In this work we propose a fast and robust registration framework based on the log-Demons diffeomorphic registration algorithm. The transformation is parameterized by stationary velocity fields (SVFs), and the similarity metric implements a symmetric local correlation coefficient (LCC). Moreover, we show how the SVF setting provides a stable and consistent numerical scheme for the computation of the Jacobian determinant and the flux of the deformation across the boundaries of a given region. Thus, it provides a robust evaluation of spatial changes. We tested the LCC-Demons in the inter-subject registration setting, by comparing with state-of-the-art registration algorithms on public available datasets, and in the intra-subject longitudinal registration problem, for the statistically powered measurements of the longitudinal atrophy in Alzheimer's disease. Experimental results show that LCC-Demons is a generic, flexible, efficient and robust algorithm for the accurate non-linear registration of images, which can find several applications in the field of medical imaging. Without any additional optimization, it solves equally well intra & inter-subject registration problems, and compares favorably to state-of-the-art methods.


Asunto(s)
Algoritmos , Enfermedad de Alzheimer/patología , Encéfalo/patología , Interpretación de Imagen Asistida por Computador/métodos , Atrofia/patología , Humanos , Neuroimagen/métodos
12.
Integr Comp Biol ; 53(4): 689-700, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23660588

RESUMEN

Related species share genetic and developmental backgrounds. Therefore, separate-sex species that share recent common ancestors with hermaphroditic species may have hidden genetic variation for sex determination that causes some level of lability of expression of gender. Worms of the polychaete species Ophryotrocha labronica have separate, dimorphic sexes and their ancestor was hermaphroditic. Ophryotrocha labronica has a worldwide distribution and populations may differ in the degree of gender specialization. We analyzed the extent to which O. labronica had fixed or labile expression of gender. We found that there were up to four different sexual phenotypes, namely, pure males, males with oocytes, pure females, and females with sperm; the relative frequency of these sexual phenotypes varied in three geographically-distant populations. These sexual morphs had either male or female morphology. However, populations differed in the extent to which worms were sexually dimorphic. In the less dioecious-like population (in which pure males and females were virtually absent, all worms had both oocytes and sperm and sexual dimorphism was relatively weak), males with oocytes had slightly plastic female allocation that depended on mating opportunities-a clearly hermaphroditic trait. Males with oocytes and females with sperm were not functional hermaphrodites. They only used one type of gametes to reproduce and in this respect they probably differed from many cases of inconstancy of gender described in the literature. We consider these populations as novel examples of intermediate states between androdioecy and dioecy. This study contributes to our understanding of breeding systems as continuous gradients rather than as distinct clear-cut alternatives.


Asunto(s)
Evolución Biológica , Variación Genética , Organismos Hermafroditas/fisiología , Fenotipo , Poliquetos/fisiología , Procesos de Determinación del Sexo/fisiología , Conducta Sexual Animal/fisiología , Animales , California , Femenino , Organismos Hermafroditas/genética , Italia , Masculino , Oocitos/citología , Poliquetos/genética , Caracteres Sexuales , Procesos de Determinación del Sexo/genética , Espermatozoides/citología , Estadísticas no Paramétricas
13.
Br J Cancer ; 106(10): 1648-59, 2012 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-22569000

RESUMEN

BACKGROUND: MEK is activated in ∼40% colorectal cancer (CRC) and 20-30% non-small cell lung cancer (NSCLC). Selumetinib is a selective inhibitor of MEK1/2, which is currently in clinical development. METHODS: We evaluated the effects of selumetinib in vitro and in vivo in CRC and NSCLC cell lines to identify cancer cell characteristics correlating with sensitivity to MEK inhibition. RESULTS: Five NSCLC and six CRC cell lines were treated with selumetinib and classified according to the median inhibitory concentration (IC(50)) values as sensitive (≤1 µM) or resistant (>1 µM). In selumetinib-sensitive cancer cell lines, selumetinib treatment induced G1 cell-cycle arrest and apoptosis and suppression of tumour growth as xenografts in immunodeficient mice. Evaluation of intracellular effector proteins and analysis of gene mutations showed no correlation with selumetinib sensitivity. Microarray gene expression profiles revealed that the activation of cAMP-dependent protein kinase A (PKA) was associated with MEK inhibitor resistance. Combined targeting of both MEK and PKA resulted in cancer cell growth inhibition of MEK inhibitor-resistant cancer cell lines in vitro and in vivo. CONCLUSION: This study provides molecular insights to explain resistance to an MEK inhibitor in human cancer cell lines.


Asunto(s)
Bencimidazoles/farmacología , Neoplasias Colorrectales/tratamiento farmacológico , Proteínas Quinasas Dependientes de AMP Cíclico/fisiología , Neoplasias Pulmonares/tratamiento farmacológico , Quinasas de Proteína Quinasa Activadas por Mitógenos/antagonistas & inhibidores , Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Línea Celular Tumoral , Proliferación Celular , Neoplasias Colorrectales/patología , Resistencia a Antineoplásicos , Activación Enzimática/efectos de los fármacos , Perfilación de la Expresión Génica , Humanos , Neoplasias Pulmonares/patología , Mutación , Ensayos Antitumor por Modelo de Xenoinjerto
14.
Leukemia ; 26(2): 280-8, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22015772

RESUMEN

We report the characterization of BMS-911543, a potent and selective small-molecule inhibitor of the Janus kinase (JAK) family member, JAK2. Functionally, BMS-911543 displayed potent anti-proliferative and pharmacodynamic (PD) effects in cell lines dependent upon JAK2 signaling, and had little activity in cell types dependent upon other pathways, such as JAK1 and JAK3. BMS-911543 also displayed anti-proliferative responses in colony growth assays using primary progenitor cells isolated from patients with JAK2(V617F)-positive myeloproliferative neoplasms (MPNs). Similar to these in vitro observations, BMS-911543 was also highly active in in vivo models of JAK2 signaling, with sustained pathway suppression being observed after a single oral dose. At low dose levels active in JAK2-dependent PD models, no effects were observed in an in vivo model of immunosuppression monitoring antigen-induced IgG and IgM production. Expression profiling of JAK2(V617F)-expressing cells treated with diverse JAK2 inhibitors revealed a shared set of transcriptional changes underlying pharmacological effects of JAK2 inhibition, including many STAT1-regulated genes and STAT1 itself. Collectively, our results highlight BMS-911543 as a functionally selective JAK2 inhibitor and support the therapeutic rationale for its further characterization in patients with MPN or in other disorders characterized by constitutively active JAK2 signaling.


Asunto(s)
Antineoplásicos/farmacología , Compuestos Heterocíclicos con 3 Anillos/farmacología , Janus Quinasa 2/antagonistas & inhibidores , Inhibidores de Proteínas Quinasas/farmacología , Antineoplásicos/química , Western Blotting , Proliferación Celular/efectos de los fármacos , Perfilación de la Expresión Génica , Compuestos Heterocíclicos con 3 Anillos/química , Humanos , Trastornos Mieloproliferativos/enzimología , Trastornos Mieloproliferativos/patología , Inhibidores de Proteínas Quinasas/química
15.
Evolution ; 65(12): 3527-42, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22133223

RESUMEN

Social parasites exploit societies, rather than organisms, and rear their brood in social insect colonies at the expense of their hosts, triggering a coevolutionary process that may affect host social structure. The resulting coevolutionary trajectories may be further altered by selection imposed by predators, which exploit the abundant resources concentrated in these nests. Here, we show that geographic differences in selection imposed by predators affects the structure of selection on coevolving hosts and their social parasites. In a multiyear study, we monitored the fate of the annual breeding attempts of the solitary nesting foundresses of Polistes biglumis wasps in four geographically distinct populations that varied in levels of attack by the congeneric social parasite, P. atrimandibularis. Foundress fitness depended mostly on whether, during the long founding phase, a colony was invaded by social parasites or attacked by predators. Foundresses from each population differed in morphological traits and reproductive tactics that were consistent with selection imposed by their natural enemies and in ways that may affect host sociality. In turn, parasite traits were consistent with selection imposed locally by hosts, implying a geographic mosaic of coevolution in this brood parasitic interaction.


Asunto(s)
Evolución Biológica , Geografía , Interacciones Huésped-Parásitos , Avispas/fisiología , Animales , Jerarquia Social , Comportamiento de Nidificación , Reproducción , Selección Genética , Conducta Sexual Animal , Conducta Social , Avispas/genética
16.
Diabetologia ; 54(6): 1539-42, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21380594

RESUMEN

AIMS/HYPOTHESIS: Impaired activity of the pentose phosphate pathway of glucose metabolism caused by hereditary deficiency of its key regulatory enzyme glucose-6-phosphate dehydrogenase (G6PD) has consequences that may worsen or attenuate the course of diabetic complications. Decreased availability of NADPH can predispose to oxidative stress and endothelial dysfunction, but can also limit the activity of the polyol pathway and cholesterol synthesis. Reduced availability of pentose phosphates for nucleic acid synthesis could impair cell proliferation. We sought to learn in which direction G6PD deficiency affects diabetic retinopathy. METHODS: We enrolled patients who were G6PD-deficient or -sufficient with type 1 diabetes of duration 15 years or longer for whom HbA(1c) records were available for at least the previous 3 years. Renal failure and smoking were exclusion criteria. For each participant seven standard field colour photographs were obtained of each eye, and retinopathy was graded in a masked fashion. RESULTS: The clinical characteristics of the 19 G6PD-deficient patients studied (age 42 ± 9 years, diabetes duration 24 ± 6 years, average HbA(1c) over 3 years 6.7 ± 0.8%) were similar to those of the 35 G6PD-sufficient patients. Almost 90% of patients in both groups had retinopathy; however, proliferative retinopathy was noted solely among G6PD-deficient patients (28%, p = 0.0036 vs G6PD-sufficient). The G6PD-deficient patients also showed a trend for increased frequency of microalbuminuria. CONCLUSIONS/INTERPRETATION: The data suggest that G6PD deficiency accelerates the microvascular complications of diabetes, and that among the consequences of G6PD deficiency those that can enhance the damage caused by diabetes outweigh those that could be protective.


Asunto(s)
Diabetes Mellitus Tipo 1/complicaciones , Retinopatía Diabética/epidemiología , Retinopatía Diabética/etiología , Deficiencia de Glucosafosfato Deshidrogenasa/complicaciones , Adolescente , Adulto , Diabetes Mellitus Tipo 1/epidemiología , Diabetes Mellitus Tipo 1/metabolismo , Retinopatía Diabética/metabolismo , Glucosafosfato Deshidrogenasa/metabolismo , Deficiencia de Glucosafosfato Deshidrogenasa/metabolismo , Hemoglobina Glucada/metabolismo , Humanos , Italia/epidemiología , Masculino , Persona de Mediana Edad , Prevalencia , Adulto Joven
17.
Am Nat ; 176(3): 249-63, 2010 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-20636132

RESUMEN

Sexual selection is often quantified using Bateman gradients, which represent sex-specific regression slopes of reproductive success on mating success and thus describe the expected fitness returns from mating more often. Although the analytical framework for Bateman gradients aimed at covering all sexual systems, empirical studies are biased toward separate-sex organisms, probably because important characteristics of other systems remain incompletely treated. Our synthesis complements the existing Bateman gradient approach with three essential reproductive features of simultaneous hermaphrodites. First, mating in one sex may affect fitness via the opposite sex, for example, through energetic trade-offs. We integrate cross-sex selection effects and show how they help characterizing sexually mutualistic versus antagonistic selection. Second, male and female mating successes may be correlated, complicating the interpretation of Bateman gradients. We show how to quantify the impact of this correlation on sexual selection and propose a principal component analysis on male and female mating success to facilitate interpretation. Third, self-fertilization is accounted for by adding selfed progeny as a separate category of reproductive success to analyses of Bateman gradients. Finally, using a worked example from the snail Biomphalaria glabrata, we illustrate how the extended analytical framework can enhance our understanding of sexual selection in hermaphroditic animals and plants.


Asunto(s)
Interpretación Estadística de Datos , Preferencia en el Apareamiento Animal/fisiología , Animales , Biomphalaria/fisiología , Trastornos del Desarrollo Sexual , Femenino , Masculino
18.
Neurobiol Aging ; 31(8): 1443-51, 1451.e1, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20541287

RESUMEN

Clinical trials of disease modifying drugs for Alzheimer's disease (AD) in patients with mild cognitive impairment (MCI) might benefit from enrichment with true AD cases. Four hundred five MCI patients (143 converters and 262 nonconverters to AD within 2 years) of the Alzheimer's disease Neuroimaging Initiative (ADNI) were used. Markers for enrichment were hippocampal atrophy on magnetic resonance (MRI), temporoparietal hypometabolism on FDG PET, cerebrospinal fluid (CSF) biomarkers (Abeta42, tau, and phospho-tau), and cortical amyloid deposition (11C-PIB positron emission tomography (PET)). Two separate enrichment strategies were tested to A) maximize the proportion of MCI converters screened in, and B) minimize the proportion of MCI converters screened out. Based on strategy A, when compared with no enrichment and ADAS-Cog as an outcome measure (sample size of 834), enrichment with 18F-FDG PET and hippocampal volume lowered samples size to 260 and 277 cases per arm, but at the cost of screening out 1,597 and 434 cases per arm. When compared with no enrichment and clinical dementia rating (CDR-SOB) as an outcome measure (sample size of 674), enrichment with hippocampal volume and Abeta42 lowered sample sizes to 191 and 291 cases per arm, with 639 and 157 screened out cases. Strategy B reduced the number of screened out cases (740 for [11C]-PIB PET, 101 hippocampal volume, 82 ADAS-COG and 330 for [18F]-FDG PET) but at the expense of decreased power and a relative increase size (740 for [11C]-PIB PET, 676 for hippocampal volume, 744 for ADAS-Cog, and 517 for [18F]-FDG PET). Enrichment comes at the price of an often relevant proportion of screened out cases, and in clinical trial settings, the balance between enrichment of screened in and loss of screened out patients should be critically discussed.


Asunto(s)
Enfermedad de Alzheimer/líquido cefalorraquídeo , Enfermedad de Alzheimer/tratamiento farmacológico , Trastornos del Conocimiento/líquido cefalorraquídeo , Trastornos del Conocimiento/tratamiento farmacológico , Preparaciones Farmacéuticas , Ensayos Clínicos Controlados Aleatorios como Asunto/métodos , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/patología , Péptidos beta-Amiloides/líquido cefalorraquídeo , Péptidos beta-Amiloides/metabolismo , Atrofia , Biomarcadores/líquido cefalorraquídeo , Trastornos del Conocimiento/patología , Femenino , Hipocampo/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Fragmentos de Péptidos/líquido cefalorraquídeo , Fragmentos de Péptidos/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Proteínas tau/líquido cefalorraquídeo , Proteínas tau/metabolismo
19.
J Biol Regul Homeost Agents ; 24(2): 225-8, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20487637

RESUMEN

Pulmonary embolism is still currently considered a very insidious disease and if not diagnosed and treated rapidly is lethal in almost 10 percent of all cases. Clinical and patient history data are essential for the diagnosis and evaluation of the clinical risk of pulmonary embolism. Pulmonary embolism, particularly during minor episodes, was primarily identified by abnormalities in D-dimer concentration during laboratory testing. Indeed, an increase in D-dimer plasma levels was consequently identified as a valid diagnostic element for pulmonary embolism and therefore, in the absence of D-dimer abnormalities, a tendency to exclude such diagnosis exists. This case report describes the importance of carrying out level II diagnostic investigations which may be particularly valid in patients with a minimal rise in D-dimer levels and a clinical suspicion of a pulmonary embolism. This method allows for a quick diagnosis with early therapeutic measures which improve survival rates during the acute and critical phase.


Asunto(s)
Productos de Degradación de Fibrina-Fibrinógeno/metabolismo , Embolia Pulmonar/sangre , Anciano , Anticoagulantes/uso terapéutico , Análisis de los Gases de la Sangre , Femenino , Fracturas Óseas/complicaciones , Humanos , Arteria Pulmonar/diagnóstico por imagen , Tomografía Computarizada por Rayos X
20.
J Exp Biol ; 213(Pt 9): 1586-90, 2010 May.
Artículo en Inglés | MEDLINE | ID: mdl-20400644

RESUMEN

Hermaphroditism and gonochorism are two contrasting forms of sexuality. Hermaphroditic species are generally seen as species adapted to conditions of low density, stabilized by poor mate search efficiency and high costs of searching. They can adjust allocation of reproductive resources to each sex function in response to current social conditions, making reproduction more efficient, at least in principle. By contrast, gonochorism (separate sexes) is advantageous when mates are frequent, making it ineffective to maintain two sex functions in a single individual. This, however, also rules out the need for a flexible response to mating opportunities as known for hermaphrodites. In the hermaphroditic marine polychaete worm Ophryotrocha diadema we showed earlier that group size is assessed through a chemical cue. In this study we verified the accuracy of the response to gradients of the chemical cue used to assess group size by O. diadema by checking reduction in egg production as the group of partners increases, as expected according to sex allocation theory. Furthermore we compared the effect of such a gradient with a similar gradient in a closely related gonochoric species (O. labronica). Here sex allocation adjustment is not predicted, thus an adaptive change in egg production in response to group-size cues is not expected. In fact, our results show that the group-size effect only occurs in O. diadema and not in O. labronica. Moreover, our study provides evidence of high perceptual abilities of chemical cues in O. diadema, suggesting that perceiving social cues and adjusting sex allocation appropriately are special properties of hermaphrodites.


Asunto(s)
Poliquetos/fisiología , Animales , Señales (Psicología) , Densidad de Población , Reproducción , Caracteres Sexuales , Conducta Sexual Animal
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