Search results for "genetics [Transcriptome]"

Does predation maintain eyespot plasticity in Bicyclus anynana?

2004

The butterfly Bicyclus anynana exhibits phenotypic plasticity involving the wet-season phenotype, which possesses marginal eyespots on the ventral surface of the wings, and the dry-season form, which lacks these eyespots. We examined the adaptive value of phenotypic plasticity of B. anynana in relation to the defence mechanisms of crypsis and deflection. We assessed the visibility differences between spotless and spotted butterflies against backgrounds of brown (dry season) or green (wet season) leaves. Spotless butterflies were highly cryptic and less predated by adult bird predators than were spotted ones when presented against brown leaf litter. However, the advantage of crypsis disappea…

Coexpression of IL-6 and soluble IL-6R causes nodular regenerative hyperplasia and adenomas of the liver

1998

Studies with tumor necrosis factor p55 receptor- and interleukin-6 (IL-6)-deficient mice have shown that IL-6 is required for hepatocyte proliferation and reconstitution of the liver mass after partial hepatectomy. The biological activities of IL-6 are potentiated when this cytokine binds soluble forms of its specific receptor subunit (sIL-6R) and the resulting complex interacts with the transmembrane signaling chain gp130. We show here that double transgenic mice expressing high levels of both human IL-6 and sIL-6R under the control of liver-specific promoters spontaneously develop nodules of hepatocellular hyperplasia around periportal spaces and present signs of sustained hepatocyte prol…

Total energy expenditure is repeatable in adults but not associated with short-term changes in body composition

2022

Low total energy expenditure (TEE, MJ/d) has been a hypothesized risk factor for weight gain, but repeatability of TEE, a critical variable in longitudinal studies of energy balance, is understudied. We examine repeated doubly labeled water (DLW) measurements of TEE in 348 adults and 47 children from the IAEA DLW Database (mean ± SD time interval: 1.9 ± 2.9 y) to assess repeatability of TEE, and to examine if TEE adjusted for age, sex, fat-free mass, and fat mass is associated with changes in weight or body composition. Here, we report that repeatability of TEE is high for adults, but not children. Bivariate Bayesian mixed models show no among or within-individual correlation between body c…

B Lymphocyte-Deficiency in Mice Causes Vascular Dysfunction by Inducing Neutrophilia

2021

B lymphocytes have been implicated in the development of insulin resistance, atherosclerosis and certain types of hypertension. In contrast to these studies, which were performed under pathological conditions, the present study provides evidence for the protective effect of B lymphocytes in maintaining vascular homeostasis under physiological conditions. In young mice not exposed to any known risk factors, the lack of B cells led to massive endothelial dysfunction. The vascular dysfunction in B cell-deficient mice was associated with an increased number of neutrophils in the circulating blood. Neutrophil depletion in B cell-deficient mice resulted in the complete normalization of vascular f…

Evolution of lactase persistence: an example of human niche construction

2011

Niche construction is the process by which organisms construct important components of their local environment in ways that introduce novel selection pressures. Lactase persistence is one of the clearest examples of niche construction in humans. Lactase is the enzyme responsible for the digestion of the milk sugar lactose and its production decreases after the weaning phase in most mammals, including most humans. Some humans, however, continue to produce lactase throughout adulthood, a trait known as lactase persistence. In European populations, a single mutation (−13910*T) explains the distribution of the phenotype, whereas several mutations are associated with it in Africa and the Middle …

Biological parameters in breast cancer.

1996

Aging, longevity, inflammation, and cancer.

2005

Cancer rates increase sharply with age in both sexes, and the majority of cases of cancer occur in patients over the age of 65 years. However, the incidence and mortality for cancer level off around 85-90 years of age, followed by a plateau, or even a decline in the last decades of life. Therefore, it seems reasonable to conclude that centenarians are endowed with a peculiar resistance to cancer. Tumor progression is a complex process that depends on interactions between tumor and host cells. One aspect of the host response, the inflammatory response, is of particular interest because it includes the release of proinflammatory cytokines, some of which may promote tumor growth and hence infl…

The influence of apo E phenotypes on the plasma triglycerides response to hormonal replacement therapy during the menopause

2001

Objective: To study the influence of apo E phenotype in plasma lipids, especially in triglycerides levels, in menopausal women receiving hormonal replacement therapy (HRT). Methods: One hundred and ten postmenopausal women were studied. Plasma total cholesterol (TC), HDL-C and triglycerides (TG) were measured before and after 3 months of HRT and the apo E phenotype was determined. According to the apo E phenotype the sample was divided into three groups: E2/E3 (n=28), E3/E3 (n=96) and E4/E3 (n=25). Results: In the pre-treatment state, higher plasma levels of TC and TC/HDL-C ratio were observed in women with phenotype E3/E4 (P<0.0001 and P<0.02, respectively), while higher plasma TG levels w…

Amplitude, Latency, and Peak Velocity in Accommodation and Disaccommodation Dynamics

2017

The aim of this work was to ascertain whether there are differences in amplitude, latency, and peak velocity of accommodation and disaccommodation responses when different analysis strategies are used to compute them, such as fitting different functions to the responses or for smoothing them prior to computing the parameters. Accommodation and disaccommodation responses from four subjects to pulse changes in demand were recorded by means of aberrometry. Three different strategies were followed to analyze such responses: fitting an exponential function to the experimental data; fitting a Boltzmann sigmoid function to the data; and smoothing the data. Amplitude, latency, and peak velocity of …

Visual-motion suppression in congenital pendular nystagmus.

2009

Patients with a congenital pendular nystagmus are known not to experience oscillopsia in a normal visual environment. The data of a 31-year-old female patient suffering from a congenital pendular nystagmus are presented. The aim of the fluorodeoxyglucose positron emission tomography (FDG-PET) experiment was to analyze the regional cerebral glucose metabolism (rCGM) during minimal as well as maximal nystagmus. Video-oculography showed a maximum in frequency of the horizontal pendular nystagmus during gaze to the left, whereas the zone of minimal nystagmus was 10 degrees to the right. Two sessions with an 18F-fluorodeoxyglucose tracer were performed to analyze cerebral blood-glucose utilizati…