Search results for " evolution"
showing 10 items of 9699 documents
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
Modeling the epidemiological history of plague in Central Asia: Palaeoclimatic forcing on a disease system over the past millennium
2010
Abstract Background Human cases of plague (Yersinia pestis) infection originate, ultimately, in the bacterium's wildlife host populations. The epidemiological dynamics of the wildlife reservoir therefore determine the abundance, distribution and evolution of the pathogen, which in turn shape the frequency, distribution and virulence of human cases. Earlier studies have shown clear evidence of climatic forcing on contemporary plague abundance in rodents and humans. Results We find that high-resolution palaeoclimatic indices correlate with plague prevalence and population density in a major plague host species, the great gerbil (Rhombomys opimus), over 1949-1995. Climate-driven models trained…
Metabolic enzymes in coelomic cells (eleocytes) of the polychaete Nereis virens: sex specific changes during sexual maturation
1993
The activities of some enzymes of the intermediary metabolism and the content of soluble protein and carbohydrate (glycogen plus free glucose) were measured in one type of coelomic cells (eleocytes) of the polychaete Nereis virens. Specimens used in this study were collected between 1989 and 1991 in Oosterscheldt Bay, The Netherlands, and divided into six different stages of sexual maturation as determined by the mean oocyte volume. In both sexes, the soluble protein content in eleocytes of immature individuals (11 mg ml−1 cell vol) increased three-fold. In prespawning N. virens the soluble protein content decreased to less than 2 mg protein ml−1 cell vol in females but not in males. In bot…
Microbial technologies for the discovery of novel bioactive metabolites
2002
Soil microbes represent an important source of biologically active compounds. These molecules present original and unexpected structure and are selective inhibitors of their molecular targets. At Biosearch Italia, discovery of new bioactive molecules is mostly carried out through the exploitation of a proprietary strain collection of over 50000 strains, mostly unusual genera of actinomycetes and uncommon filamentous fungi. A critical element in a drug discovery based on microbial extracts is the isolation of unexploited groups of microorganisms that are at the same time good producers of secondary metabolites. Molecular genetics can assist in these efforts. We will review the development an…
Molecular Surveillance of HIV-1 in Madrid, Spain: a Phylogeographic Analysis ▿
2011
ABSTRACT The molecular epidemiology of HIV-1 is constantly changing, mainly as a result of human migratory flows and the high adaptive ability of the virus. In recent years, Spain has become one of Europe's main destinations for immigrants and one of the western European countries with the highest rates of HIV-positive patients. Using a phylogeographic approach, we have analyzed the relationship between HIV-1 variants detected in immigrant and native populations of the urban area of Madrid. Our project was based on two coincidental facts. First, resistance tests were extended to naïve and newly diagnosed patients, and second, the Spanish government legislated the provision of legal status t…
Multidirectional chromosome painting reveals a remarkable syntenic homology between the greater galagos and the slow loris.
2006
We report on the first reciprocal chromosome painting of lorisoids and humans. The chromosome painting showed a remarkable syntenic homology between Otolemur and Nycticebus. Eight derived syntenic associations of human segments are common to both Otolemur and Nycticebus, indicative of a considerable period of common evolution between the greater galago and the slow loris. Five additional Robertsonian translocations form the slow loris karyotype, while the remaining chromosomes are syntenically equivalent, although some differ in terms of centromere position and heterochromatin additions. Strikingly, the breakpoints of the human chromosomes found fragmented in these two species are apparentl…