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1.
Phys Rev Lett ; 129(19): 195002, 2022 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-36399755

RESUMEN

The application of an external 26 Tesla axial magnetic field to a D_{2} gas-filled capsule indirectly driven on the National Ignition Facility is observed to increase the ion temperature by 40% and the neutron yield by a factor of 3.2 in a hot spot with areal density and temperature approaching what is required for fusion ignition [1]. The improvements are determined from energy spectral measurements of the 2.45 MeV neutrons from the D(d,n)^{3}He reaction, and the compressed central core B field is estimated to be ∼4.9 kT using the 14.1 MeV secondary neutrons from the D(T,n)^{4}He reactions. The experiments use a 30 kV pulsed-power system to deliver a ∼3 µs current pulse to a solenoidal coil wrapped around a novel high-electrical-resistivity AuTa_{4} hohlraum. Radiation magnetohydrodynamic simulations are consistent with the experiment.

2.
Phys Rev Lett ; 121(24): 242002, 2018 Dec 14.
Artículo en Inglés | MEDLINE | ID: mdl-30608729

RESUMEN

We report the first observation of the parity-violating gamma-ray asymmetry A_{γ}^{np} in neutron-proton capture using polarized cold neutrons incident on a liquid parahydrogen target at the Spallation Neutron Source at Oak Ridge National Laboratory. A_{γ}^{np} isolates the ΔI=1, ^{3}S_{1}→^{3}P_{1} component of the weak nucleon-nucleon interaction, which is dominated by pion exchange and can be directly related to a single coupling constant in either the DDH meson exchange model or pionless effective field theory. We measured A_{γ}^{np}=[-3.0±1.4(stat)±0.2(syst)]×10^{-8}, which implies a DDH weak πNN coupling of h_{π}^{1}=[2.6±1.2(stat)±0.2(syst)]×10^{-7} and a pionless EFT constant of C^{^{3}S_{1}→^{3}P_{1}}/C_{0}=[-7.4±3.5(stat)±0.5(syst)]×10^{-11} MeV^{-1}. We describe the experiment, data analysis, systematic uncertainties, and implications of the result.

3.
Regul Toxicol Pharmacol ; 97: 88-97, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29894733

RESUMEN

Reduced Risk Products (RRPs) do not burn tobacco and produce lower levels of toxicants than in cigarette smoke. The long-term effects of using RRPs on health are difficult to assess in a pre-market setting and a modeling approach is required to quantify harm reduction. The Population Health Impact Model (Weitkunat et al., 2015) follows a hypothetical population of individuals over time, creating their tobacco use histories and, based on these, estimating relative and absolute risks of lung cancer, ischemic heart disease, stroke and chronic obstructive pulmonary disease. Linking the tobacco use to the risk profile allow us to assess how the relative and absolute risks of these diseases vary between individuals aged 20, 30, 40 or 50 at baseline who have never smoked or who initiated smoking at 19 years old and either continued to smoke, quit smoking, or switched to RRPs with varying degrees of harm reduction. The simulations suggest that, for smokers in their 20s-30s quitting, or switching to RRP primarily prevents the accrual of risk, while in their 40s-50s it reduces risk. Though tobacco prevention has been the primary approach to limit smoking-related diseases, RRPs can also substantially reduce risks in individuals who do not quit.


Asunto(s)
Neoplasias Pulmonares/inducido químicamente , Isquemia Miocárdica/inducido químicamente , Enfermedad Pulmonar Obstructiva Crónica/inducido químicamente , Accidente Cerebrovascular/inducido químicamente , Productos de Tabaco/efectos adversos , Uso de Tabaco/efectos adversos , Adulto , Femenino , Humanos , Neoplasias Pulmonares/epidemiología , Masculino , Persona de Mediana Edad , Modelos Teóricos , Isquemia Miocárdica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Factores de Riesgo , Accidente Cerebrovascular/epidemiología , Adulto Joven
4.
Phytopathology ; 107(12): 1522-1531, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28762287

RESUMEN

Incorporating disease resistance into cultivars is a primary focus of modern breeding programs. Resistance to pathogens is often introgressed from landrace or wild individuals with poor fruit quality into commercial-quality cultivars. Sites of multiple disease resistance (MDR) are regions or "hot spots" of the genome with closely linked genes for resistance to different pathogens that could enable rapid incorporation of resistance. An F2-derived F6 recombinant inbred line population from a cross between 'Criollo de Morelos 334' (CMM334) and 'Early Jalapeno' was evaluated in inoculated fruit studies for susceptibility to oomycete and fungal pathogens: Phytophthora capsici, P. nicotianae, Botrytis cinerea, Fusarium oxysporum, F. solani, Sclerotinia sclerotiorum, Alternaria spp., Rhizopus oryzae, R. stolonifer, and Colletotrichum acutatum. All isolates evaluated were virulent on pepper. Significant differences in disease susceptibility were identified among lines for each of the pathogens evaluated. P. capsici was the most virulent pathogen, while R. oryzae and one Sclerotinia isolate were the least virulent. Quantitative trait loci associated with resistance were identified for Alternaria spp. and S. sclerotiorum. Positive correlations in disease incidence were detected between Alternaria spp. and F. oxysporum, F. solani, and C. acutatum, as well as between C. acutatum and Botrytis spp., F. oxysporum, F. solani, and P. capsici. No sites of MDR were identified for pathogens tested; however, positive correlations in disease incidence were detected among pathogens suggesting there may be genetic linkage among resistance genes in CM334 and Early Jalapeno.


Asunto(s)
Capsicum/inmunología , Resistencia a la Enfermedad/genética , Hongos/fisiología , Phytophthora/fisiología , Enfermedades de las Plantas/inmunología , Sitios de Carácter Cuantitativo/genética , Capsicum/genética , Capsicum/microbiología , Frutas/genética , Frutas/inmunología , Frutas/microbiología , Ligamiento Genético , Enfermedades de las Plantas/microbiología
5.
Plant Dis ; 99(12): 1689-1694, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30699514

RESUMEN

Boxwood blight caused by Calonectria pseudonaviculata is typically expressed as a foliage disease with aboveground symptoms including defoliation, dieback and formation of dark narrow stem cankers. Whether this pathogen behaves like other Calonectria spp. and has a significant soil phase in the epidemiology of boxwood blight is not known. In this study we observed experimentally that (1) the boxwood blight pathogen consistently forms microsclerotia in artificially inoculated leaves and roots of Buxus spp., (2) soil artificially inoculated with conidia and microsclerotia of this pathogen can cause foliar blight, (3) conidia and microsclerotia can remain viable in soil for up to 3 and at least 40 weeks, respectively (4) and the pathogen can cause crown and root rot to plants only when roots and crowns are directly exposed to relatively high inoculum levels. Our results suggest that C. pseudonaviculata is primarily a foliar pathogen with a potentially epidemiologically significant soil phase.

6.
Surgeon ; 13(1): 19-33, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24206935

RESUMEN

BACKGROUND: Survival in oesophageal cancer remains poor with high post-operative recurrence rates. PET/CT was introduced to the Three-Counties Cancer Network (3CCN) in 2006 to detect 'occult' metastatic disease not seen with conventional staging modalities. This study aims to determine whether the introduction of Integrated fluorodeoxyglucose (18F) Positron Emission Tomography (PET/CT) has changed the management, improved survival or reduced the rate of early post-operative recurrence in patients with operable oesophageal cancer. METHODS: A retrospective review was undertaken of all patients diagnosed with oesophageal cancer in the 3CCN from 2005 to 2009. Early recurrence was defined as proven recurrence locally or at a distant site within one year of resection. RESULTS: 725 patients were identified. 200 (27.6%) patients underwent staging PET/CT. PET/CT altered treatment intent in 19 (9.5%) patients. 128 (17.7%) patients underwent oesophageal resection, 90 (70.3%) of which had a staging PET/CT. No significant difference was noted in post-operative mortality (4.4% Vs 5.3%, p = 0.8) or early recurrence where PET/CT was performed when adjusted for age, sex, stage or neo-adjuvant chemotherapy (p = 0.761, OR 1.136[95% CI 0.499-2.585]). PET/CT had no significant effect on survival (log-rank test; Chi-square 0.710, p = 0.4). CONCLUSION: PET/CT has improved the accuracy of oesophageal cancer staging avoiding potentially unnecessary surgery. Ultimately however, its use has had no effect on early recurrence or survival rates. Inaccurate identification of occult metastatic disease prior to the introduction of staging PET/CT does not appear to be the primary cause of early recurrence in patients with oesophageal cancer.


Asunto(s)
Neoplasias Esofágicas/diagnóstico , Fluorodesoxiglucosa F18/farmacología , Recurrencia Local de Neoplasia/epidemiología , Estadificación de Neoplasias , Tomografía de Emisión de Positrones/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias Esofágicas/mortalidad , Neoplasias Esofágicas/cirugía , Esofagectomía , Femenino , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Pronóstico , Radiofármacos/farmacología , Estudios Retrospectivos , Tasa de Supervivencia/tendencias , Reino Unido/epidemiología
7.
Dev Biol ; 372(1): 5-16, 2012 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-23010510

RESUMEN

Establishment and maintenance of functional stem cells is critical for organ development and tissue homeostasis. Little is known about the mechanisms underlying stem establishment during organogenesis. Drosophila testes are among the most thoroughly characterized systems for studying stem cell behavior, with germline stem cells (GSCs) and somatic cyst stem cells (CySCs) cohabiting a discrete stem cell niche at the testis apex. GSCs and CySCs are arrayed around hub cells that also comprise the niche and communication between hub cells, GSCs, and CySCs regulates the balance between stem cell maintenance and differentiation. Recent data has shown that functional, asymmetrically dividing GSCs are first established at ∼23 h after egg laying during Drosophila testis morphogenesis (Sheng et al., 2009). This process correlates with coalescence of the hub, but development of CySCs from somatic gonadal precursors (SGPs) was not examined. Here, we show that functional CySCs are present at the time of GSC establishment, and that Jak-STAT signaling is necessary and sufficient for CySC maintenance shortly thereafter. Furthermore, hyper-activation of Jak in CySCs promotes expansion of the GSC population, while ectopic Jak activation in the germline induces GSC gene expression in GSC daughter cells but does not prevent spermatogenic differentiation. Together, these observations indicate that, similar to adult testes, Jak-STAT signaling from the hub acts on both GSCs and CySC to regulate their development and differentiation, and that additional signaling from CySCs to the GSCs play a dominant role in controlling GSC maintenance during niche formation.


Asunto(s)
Diferenciación Celular , Proteínas de Drosophila/genética , Drosophila/embriología , Drosophila/genética , Quinasas Janus/genética , Factores de Transcripción STAT/genética , Testículo/citología , Factores de Transcripción/genética , Animales , Drosophila/metabolismo , Proteínas de Drosophila/metabolismo , Embrión no Mamífero/metabolismo , Células Germinativas/citología , Células Germinativas/metabolismo , Quinasas Janus/metabolismo , Masculino , Modelos Biológicos , Morfogénesis , Factores de Transcripción STAT/metabolismo , Transducción de Señal , Nicho de Células Madre/genética , Células Madre/citología , Células Madre/metabolismo , Testículo/metabolismo , Factores de Transcripción/metabolismo
8.
J Exp Med ; 150(6): 1577-81, 1979 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-512591

RESUMEN

Rat hepatocytes in short-term monolayer cultures bound radiolabeled polymeric rat IgA but not IgG. The binding of 125I-IgA was inhibited equally well by unlabeled polymeric IgA and by antiserum to rat secretory component (SC). The antibody to SC, after specific purification and radiolabeling, was bound to hepatocytes as effectively as the IgA. These results indicate that SC acts as the receptor for polymeric IgA on rat hepatocytes as it does on human gut epithelia, and that the transport of IgA from blood to bile in rats across the liver is analogous to that of IgA across human enterocytes.


Asunto(s)
Inmunoglobulina A/metabolismo , Fragmentos de Inmunoglobulinas , Hígado/inmunología , Receptores Inmunológicos/metabolismo , Componente Secretorio , Animales , Reacciones Antígeno-Anticuerpo , Transporte Biológico , Células Cultivadas , Sustancias Macromoleculares , Ratas
9.
Science ; 175(4018): 192-4, 1972 Jan 14.
Artículo en Inglés | MEDLINE | ID: mdl-5008438

RESUMEN

The rate of (35)S incorporation into cerebroside sulfate in cultures of embryo mouse spinal cord shows a rapid acceleration at the time of myelin formation. Exposure of cultures to dilute serum from rabbits with experimental allergic encephalomyelitis results in almost complete inhibition of sulfatide synthesis. Within 24 hours after replacement of inhibiting medium with normal medium there is an increase in sulfatide synthesis followed by myelination.


Asunto(s)
Cerebrósidos/biosíntesis , Encefalomielitis/sangre , Médula Espinal/metabolismo , Animales , Autorradiografía , Técnicas de Cultivo , Embrión de Mamíferos , Ratones , Sulfatos/metabolismo , Sulfoglicoesfingolípidos/análisis , Sulfoglicoesfingolípidos/biosíntesis , Isótopos de Azufre , Factores de Tiempo
10.
Science ; 183(4124): 540-2, 1974 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-4203489

RESUMEN

Antiserum to cerebroside was prepared in rabbits by injection of cerebroside together with bovine serum albumin in complete Freund's adjuvant. When applied to cultures of embryo mouse spinal cord at explantation, this antiserum inhibited sulfatide synthesis and myelination; when applied to myelinated cultures it inhibited sulfatide synthesis and produced demyelination. Complement fixation assays also show antibody to cerebroside in serums from rabbits with experimental allergic encephalomyelitis induced by injection of whole white matter. Absorption of such serum with cerebroside abolishes the inhibiting and demyelinating activities.


Asunto(s)
Anticuerpos , Cerebrósidos , Vaina de Mielina , Proteínas del Tejido Nervioso , Médula Espinal/metabolismo , Sulfoglicoesfingolípidos/biosíntesis , Animales , Formación de Anticuerpos , Reacciones Antígeno-Anticuerpo , Pruebas de Fijación del Complemento , Técnicas de Cultivo , Embrión de Mamíferos , Adyuvante de Freund , Sueros Inmunes/farmacología , Inmunización , Ratones , Mycobacterium tuberculosis/inmunología , Fosfatidilcolinas , Conejos/inmunología , Albúmina Sérica Bovina , Sulfatos/metabolismo , Radioisótopos de Azufre
11.
BMC Evol Biol ; 8: 295, 2008 Oct 26.
Artículo en Inglés | MEDLINE | ID: mdl-18950531

RESUMEN

BACKGROUND: Quantifying the amount of standing genetic variation in fitness represents an empirical challenge. Unfortunately, the shortage of detailed studies of the genetic architecture of fitness has hampered progress in several domains of evolutionary biology. One such area is the study of sexual selection. In particular, the evolution of adaptive female choice by indirect genetic benefits relies on the presence of genetic variation for fitness. Female choice by genetic benefits fall broadly into good genes (additive) models and compatibility (non-additive) models where the strength of selection is dictated by the genetic architecture of fitness. To characterize the genetic architecture of fitness, we employed a quantitative genetic design (the diallel cross) in a population of the seed beetle Callosobruchus maculatus, which is known to exhibit post-copulatory female choice. From reciprocal crosses of inbred lines, we assayed egg production, egg-to-adult survival, and lifetime offspring production of the outbred F1 daughters (F1 productivity). RESULTS: We used the bio model to estimate six components of genetic and environmental variance in fitness. We found sizeable additive and non-additive genetic variance in F1 productivity, but lower genetic variance in egg-to-adult survival, which was strongly influenced by maternal and paternal effects. CONCLUSION: Our results show that, in order to gain a relevant understanding of the genetic architecture of fitness, measures of offspring fitness should be inclusive and should include quantifications of offspring reproductive success. We note that our estimate of additive genetic variance in F1 productivity (CVA=14%) is sufficient to generate indirect selection on female choice. However, our results also show that the major determinant of offspring fitness is the genetic interaction between parental genomes, as indicated by large amounts of non-additive genetic variance (dominance and/or epistasis) for F1 productivity. We discuss the processes that may maintain additive and non-additive genetic variance for fitness and how these relate to indirect selection for female choice.


Asunto(s)
Escarabajos/genética , Vigor Híbrido , Preferencia en el Apareamiento Animal , Selección Genética , Animales , Cruzamientos Genéticos , Evolución Molecular , Femenino , Variación Genética , Genética de Población , Genotipo , Patrón de Herencia , Modelos Genéticos , Fenotipo , Carácter Cuantitativo Heredable
12.
Artículo en Inglés | MEDLINE | ID: mdl-30136978

RESUMEN

Much research has been done regarding how to visualize and interact with observations and attributes of high-dimensional data for exploratory data analysis. From the analyst's perceptual and cognitive perspective, current visualization approaches typically treat the observations of the high-dimensional dataset very differently from the attributes. Often, the attributes are treated as inputs (e.g., sliders), and observations as outputs (e.g., projection plots), thus emphasizing investigation of the observations. However, there are many cases in which analysts wish to investigate both the observations and the attributes of the dataset, suggesting a symmetry between how analysts think about attributes and observations. To address this, we define SIRIUS (Symmetric Interactive Representations In a Unified System), a symmetric, dual projection technique to support exploratory data analysis of high-dimensional data. We provide an example implementation of SIRIUS and demonstrate how this symmetry affords additional insights.

13.
Neuroscience ; 148(2): 375-84, 2007 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-17640817

RESUMEN

Dehydroepiandrosterone sulfate (DHEAS) has been shown to enhance memory retention in different animal models and in various learning paradigms. In the present study, we investigated the effect of peripherally administered DHEAS on the acquisition, consolidation and retention of memory using a weak version of the one-trial passive avoidance task in day-old chicks. Intraperitoneally administered DHEAS (20 mg/kg) either 30 min before or 30 min and 4.5 h after training on the weakly aversive stimulus, enhanced recall at 24 h following training, suggesting a potentiation of not only the acquisition but also the early and late phases of memory consolidation. In contrast, when DHEAS was administered at 30 min prior to the 24 h retention test there was no memory enhancement, indicating a lack of effect on memory retrieval. Memory recall was unaltered when DHEAS was administered at 30 min before training in a control group trained on a strongly aversive stimulus, confirming memory-specific effects. Interestingly, the memory enhancement appeared to be sex-specific as male chicks showed higher recall than females. These findings provide further evidence that DHEAS enhances memory and may be involved in the temporal cascade of long-term memory formation.


Asunto(s)
Sulfato de Deshidroepiandrosterona/farmacología , Memoria/efectos de los fármacos , Animales , Animales Recién Nacidos , Reacción de Prevención/efectos de los fármacos , Conducta Animal/efectos de los fármacos , Embrión de Pollo , Pollos , Sulfato de Deshidroepiandrosterona/metabolismo , Femenino , Masculino , Factores Sexuales , Estadísticas no Paramétricas , Factores de Tiempo , Tritio/metabolismo
14.
Plant Dis ; 91(9): 1170-1179, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-30780659

RESUMEN

We compared photosynthesis and multispectral radiometry (MSR) measurements with visual quality ratings for assessment of feeding injury to creeping bentgrass caused by the lance nematode (Hoplolaimus galeatus) using artificially infested microplots and a naturally infested putting green. Nematode feeding resulted in negative visual and MSR effects on creeping bentgrass in microplots. Visual quality ratings were correlated more consistently with nematode densities than either individual MSR variables or factor models of MSR variables. Threshold estimates for H. galeatus population densities associated with unacceptable bentgrass quality in microplots varied widely by month and year. Similarly, the relationship between H. galeatus population density and turf health indicators (including MSR measurements, visual ratings, and net photosynthetic rate) varied with cultivar and management practice (irrigation frequency and mowing height) in the naturally infested putting green. Notably, negative effects of nematode feeding were not consistently associated with more stressful management practices, suggesting that stress avoidance is not a reliable deterrent to H. galeatus damage in creeping bentgrass. Damage thresholds for this nematode-host association are dynamic and should be used with caution.

15.
Endocrinology ; 147(1): 179-90, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16223859

RESUMEN

Steroids in the brain arise both from local synthesis and from peripheral sources and have a variety of effects on neuronal function. However, there is little direct chemical evidence for the range of steroids present in brain or of the pathways for their synthesis and inactivation. This information is a prerequisite for understanding the regulation and function of brain steroids. After extraction from adult male rat brain, we have fractionated free steroids and their sulfate esters and then converted them to heptafluorobutyrate or methyloxime-trimethylsilyl ether derivatives for unequivocal identification and assay by gas chromatography analysis and selected ion monitoring mass spectrometry. In the free steroid fraction, corticosterone, 3alpha,5alpha-tetrahydrodeoxycorticosterone, testosterone, and dehydroepiandrosterone were found in the absence of detectable precursors usually found in endocrine glands, indicating peripheral sources and/or alternative synthetic pathways in brain. Conversely, the potent neuroactive steroid 3alpha,5alpha-tetrahydroprogesterone (allopregnanolone) was found in the presence of its precursors pregnenolone, progesterone, and 5alpha-dihydroprogesterone. Furthermore, the presence of 3beta-, 11beta-, 17alpha-, and 20alpha-hydroxylated metabolites of 3alpha,5alpha-tetrahydroprogesterone implicated possible inactivation pathways for this steroid. The 20alpha-reduced metabolites could also be found for pregnenolone, progesterone, and 5alpha-dihydroprogesterone, introducing a possible regulatory diversion from the production of 3alpha,5alpha-tetrahydroprogesterone. In the steroid sulfate fraction, dehydroepiandrostrone sulfate was identified but not pregnenolone sulfate. Although pharmacologically active, identification of the latter appears to be an earlier methodological artifact, and the compound is thus of doubtful physiological significance in the adult brain. Our results provide a basis for elucidating the origins and regulation of brain steroids.


Asunto(s)
Andrógenos/análisis , Química Encefálica , Hormonas Esteroides Gonadales/análisis , Progesterona/análisis , Andrógenos/aislamiento & purificación , Animales , Cromatografía de Gases y Espectrometría de Masas , Hormonas Esteroides Gonadales/aislamiento & purificación , Masculino , Progesterona/aislamiento & purificación , Ratas , Ratas Sprague-Dawley
16.
Plant Dis ; 90(1): 44-50, 2006 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30786473

RESUMEN

The effects of management practices and nematode population density on the seasonal fluctuationsin lance nematode (Hoplolaimus galeatus) populations in creeping bentgrass were studiedin a naturally infested experimental putting green and in artificially infested microplots. In general, H. galeatus populations increased from late spring through midsummer, declined in August, and increased again in the fall. Population increase in microplots was strongly density dependent, with final population densities inversely proportional to inoculum levels. Ectoparasitic populationsof H. galeatus in both studies were composed of adults and juveniles, whereas endoparasiticpopulations were almost exclusively juveniles. H. galeatus populations in the naturallyinfested site were aggregated spatially, but the aggregation was not temporally stable. Nematodepopulations were not affected by bentgrass cultivar selection or irrigation frequency.

17.
J Small Anim Pract ; 57(9): 459-64, 2016 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27271454

RESUMEN

OBJECTIVES: To describe serum C-reactive protein and S100A12 concentrations in dogs with hepatic disease and to determine whether there is a relationship between the concentration of either and the severity of hepatic necroinflammation. METHODS: Serum C-reactive protein and S100A12 concentrations were measured in 46 dogs undergoing hepatic biopsy. Dogs were divided into three groups: congenital portosystemic shunts, chronic hepatitis and hepatic neoplasia. The histological severity of hepatic necroinflammation was scored. RESULTS: C-reactive protein and S100A12 concentrations were greater than the upper limit of the reference intervals in 39 and 26% of dogs, respectively. There was no association of disease group with C-reactive protein (P=0·1733) or S100A12 (P=0·1513) concentrations. There was a positive correlation between serum C-reactive protein concentration and hepatic necroinflammatory activity (rs =0·428, P=0·006). CLINICAL SIGNIFICANCE: Increased serum C-reactive protein and S100A12 concentrations were observed in a subpopulation of dogs with various types of hepatic diseases, suggesting acute-phase inflammation and activation of phagocytic cells, respectively. Dogs with higher hepatic necroinflammatory activity scores tended to have higher serum C-reactive protein concentrations. Further studies are needed to confirm this finding in a larger group of dogs.


Asunto(s)
Biomarcadores/sangre , Proteínas Sanguíneas/metabolismo , Enfermedades de los Perros/sangre , Hepatopatías/sangre , Proteína S100A12/sangre , Animales , Enfermedades de los Perros/patología , Perros , Femenino , Masculino , Valor Predictivo de las Pruebas , Índice de Severidad de la Enfermedad
18.
Genes Brain Behav ; 4(4): 209-28, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15924554

RESUMEN

The midbrain dopamine system mediates normal and pathologic behaviors related to motor activity, attention, motivation/reward and cognition. These are complex, quantitative traits whose variation among individuals is modulated by genetic, epigenetic and environmental factors. Conventional genetic methods have identified several genes important to this system, but the majority of factors contributing to the variation remain unknown. To understand these genetic and environmental factors, we initiated a study measuring 21 behavioral and neurochemical traits in 15 common inbred mouse strains. We report trait data, heritabilities and genetic and non-genetic correlations between pheno-types. In general, the behavioral traits were more heritable than neurochemical traits, and both genetic and non-genetic correlations within these trait sets were high. Surprisingly, there were few significant correlations between the behavioral and the individual neurochemical traits. However, striatal serotonin and one measure of dopamine turnover (DOPAC/DA) were highly correlated with most behavioral measures. The variable accounting for the most variation in behavior was mouse strain and not a specific neurochemical measure, suggesting that additional genetic factors remain to be determined to account for these behavioral differences. We also report the prospective use of the in silico method of quantitative trait loci (QTL) analysis and demonstrate difficulties in the use of this method, which failed to detect significant QTLs for the majority of these traits. These data serve as a framework for further studies of correlations between different midbrain dopamine traits and as a guide for experimental cross designs to identify QTLs and genes that contribute to these traits.


Asunto(s)
Química Encefálica/genética , Mapeo Cromosómico/métodos , Bases de Datos Genéticas , Ratones Endogámicos/genética , Actividad Motora/genética , Animales , Monoaminas Biogénicas/metabolismo , Cromatografía Líquida de Alta Presión , Dopamina/fisiología , Electroquímica , Variación Genética , Habituación Psicofisiológica/genética , Masculino , Mesencéfalo/metabolismo , Ratones , Análisis Multivariante , Neostriado/química , Neostriado/metabolismo , Fenotipo , Polimorfismo de Nucleótido Simple , Análisis de Componente Principal
19.
Genetics ; 134(4): 1237-47, 1993 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-8375658

RESUMEN

A locus influencing floral pigment intensity in the morning glory, Ipomoea purpurea, is polymorphic throughout the southeastern United States. Previous work has suggested that the white allele at this locus has a transmission advantage during mating because of the effect of flower color on pollinator behavior. The experiment described here was designed to determine whether other effects of the W locus may contribute an opposing selective advantage to the dark allele. Dark homozygotes were vegetatively smaller and produced fewer flowers, seed capsules and seeds than either light heterozygotes or white homozygotes. In addition, dark homozygotes produced smaller seeds than heterozygotes, and there is some indication that white homozygotes also produced smaller seeds than heterozygotes. Pleiotropic effects on seed number thus do not seem to contribute to selection opposing the mating advantage associated with the white allele. However, pleiotropic effects on seed size might contribute to overdominance that could stabilize the W locus polymorphism.


Asunto(s)
Pigmentación/genética , Plantas/genética , Análisis de Varianza , Genotipo , Desarrollo de la Planta , Reproducción
20.
Genetics ; 144(2): 671-88, 1996 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8889529

RESUMEN

We have investigated genetic interactions between spontaneous mutations affecting abdominal and sternopleural bristle number that have accumulated in 12 long-term selection lines derived from an inbred strain, and mutations at 14 candidate bristle number quantitative trait loci. The quantitative test for complementation was to cross the selection lines to an inbred wild-type strain (the control cross) and to a derivative of the control strain into which the mutant allele at the candidate locus to be tested was substituted (the tester strain). Genetic interactions between spontaneous mutations affecting bristle number and the candidate locus mutations were common, and in several cases the interaction effects were different in males and females. Analyses of variance of the (tester- control) differences among and within groups of replicate lines selected in the same direction for the same trait showed significant group effects for several candidate loci. Genetically, the interactions could be caused by allelism of, and/ or epistasis between, spontaneous mutations in the selection lines and the candidate locus mutations. It is possible that much of the response to selection was from new mutations at candidate bristle number quantitative trait loci, and that for some of these loci, mutation rates were high.


Asunto(s)
Drosophila melanogaster/genética , Genes de Insecto , Selección Genética , Análisis de Varianza , Animales , Mapeo Cromosómico , Femenino , Prueba de Complementación Genética , Masculino , Mutación , Filogenia
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