Search results for "evolution"
showing 10 items of 11096 documents
Un ecosistema malalt: la lluita contra la resistència a antibiòtics des d’una perspectiva global
2013
La produccio antropogenica d'antibiotics ha provocat una malaltia dels ecosistemes microbians de dimensio planetaria, la repercussio mes immediata de la qual per a l'home es la intractabilitat de les infeccions. La comprensio del fenomen i les possibilitats d'intervencio requereixen nous metodes conceptuals, analitics i tecnologics.
What is the amygdala? A comparative approach.
1999
Patterns and rates of nucleotide substitution, insertion and deletion in the endosymbiont of antsBlochmannia floridanus
2009
Genome reduction is a general process that has been studied in numerous symbiotic bacteria associated with insects. We investigated the last stages of genome degradation in Blochmannia floridanus, a mutualistic bacterial endosymbiont of the ant Camponotus floridanus. We determined the tempo (rates of insertion and deletion) and mode (size and number of insertion-deletion events) of the process in the last 200,000 years by analysing a total of 16 intergenic regions in several strains of this endosymbiont from different ant populations. We provide the first calculation of the reduction rate for noncoding DNA in this endosymbiont (2.2 x 10(-8) lost nucleotides/site/year) and compare it with th…
A single key-odorant accounts for the pheromonal effect of rabbit milk : Further test of the mammary pheromone's activity against a wide sample of vo…
2003
In the rabbit, lactating females emit a volatile compound in milk, the mammary pheromone (MP), that triggers rooting for the nipple and its grasping in pups. Previous studies have shown that the MP seems to act selectively, in terms both of intensity and quality. Here, we aimed to add new evidence to these properties of the MP. Newborn rabbits (n=825) were submitted to an oral activation test allowing to measure their searching/grasping responses towards different stimuli. In Experiment 1 we assessed whether pups respond to the MP in an intensity-dependent manner. In Experiment 2 we assessed the activity of 20 volatiles previously identified in rabbit milk, other than the MP, which were nev…
Effects of time of day on resistance exercise-induced anabolic signaling in skeletal muscle
2013
This study examined the effect of morning versus afternoon exercise on acute responses in phosphorylation of proteins regulating muscle size and metabolism. Twenty-two untrained men, divided into the morning (n = 11) or afternoon (n = 11) group, performed maximal isometric leg extensions before and after resistance loading at 07:30–08:30 h and 16:00–17:00 h, respectively. Muscle pre- and postloading biopsies were analyzed for phosphorylated Akt, p70S6K, rpS6, p38 mitogen-activated protein kinase (MAPK), Erk1/2, and eukaryotic elongation factor (eEF) 2. Muscle force declined after exercise in both groups (p < 0.001). p70S6K Thr389 (p < 0.05) and Thr421/Ser424 and rpS6 (all p < 0.001) increas…
Structural alterations of faecal and mucosa-associated bacterial communities in irritable bowel syndrome
2012
Summary Irritable bowel syndrome (IBS) is the most common functional gastrointestinal disorder in western coun- tries. Previous studies on IBS, mostly based on faecal samples, suggest alterations in the intestinal micro- biota. However, no consensus has been reached regarding the association between specific bacteria and IBS. We explore the alterations of intestinal bac- terial communities in IBS using massive sequencing of amplified 16S rRNA genes. Mucosal biopsies of the ascending and descending colon and faeces from 16 IBS patients and 9 healthy controls were analysed. Strong inter-individual variation was observed in the composition of the bacterial communities in both patients and cont…
Signal transduction in isolated fat body from the cockroach Blaptica dubia exposed to hypertrehalosaemic neuropeptide
1998
Hypertrehalosaemic hormones stimulate trehalogenesis while inhibiting glycolysis in cockroach fat body. Signal transduction of the hypertrehalosaemic peptide Bld HrTH was examined in isolated fat body of the Argentine cockroach Blaptica dubia with respect to its effects on the increase in trehalose production and decrease in the content of the glycolytic activator fructose 2,6-bisphosphate in the tissue. Cyclic AMP does not seem to be involved in these processes as the cAMP analogue cpt-cAMP and the phosphodiesterase inhibitor IBMX, which both permeate cell membranes, had no effect on either parameter. Octopamine at physiological concentrations (10−7 mol · l−1) was also ineffective, but at …
Seducin, male sex pheromone of the cockroachNauphoeta cinerea: Isolation, identification, and bioassay.
1990
The male sex pheromone of the cockroachNauphoeta cinerea was isolated from adult sternal glands and identified by gas chromatography-mass spectrometry. This pheromone, which attracts females from a distance, is a multicomponent blend. It is composed principally of three compounds: 3-hydroxy-2-butanone (acetoin), 2-methylthiazolidine, and 4-ethyl-2-meth-oxyphenol. A mixture of synthetic compounds in a ratio of 4∶4∶1 (2700 ng) elicits maximal response and short latency of response by receptive females, similar to that induced by male sternal gland extracts. Tested separately, each compound induces a positive response, but the moving times spent by females are generally longer than with the mi…
Three-dimensional parametric modeling of bicuspid aortopathy and comparison with computational flow predictions
2017
Bicuspid aortic valve (BAV)-associated ascending aneurysmal aortopathy (namely "bicuspid aortopathy") is a heterogeneous disease making surgeon predictions particularly challenging. Computational flow analysis can be used to evaluate the BAV-related hemodynamic disturbances, which likely lead to aneurysm enlargement and progression. However, the anatomic reconstruction process is time consuming so that predicting hemodynamic and structural evolution by computational modeling is unfeasible in routine clinical practice. The aim of the study was to design and develop a parametric program for three-dimensional (3D) representations of aneurysmal aorta and different BAV phenotypes starting from s…
Quality-of-Life Impairment among Patients with Hidradenitis Suppurativa: A Cross-Sectional Study of 1795 Patients
2021
The chronic, inflammatory skin disorder hidradenitis suppurativa (HS) is associated well documented negative influences on patients&rsquo