Island environments have the potential to change evolutionary trajectories of morphological traits in species relative to their mainland counterparts due to habitat and resource differences, or by reductions in the intensity of social or sexual selection. Latitude, island size, and isolation may further influence trait evolution through biases in colonization rates. We used a global dataset of passerine plumage color as a model group to identify selective pressures driving morphological evolution of island animals using phylogenetically-controlled analyses.
View Article and Find Full Text PDFBackground: Healthcare-associated infections due to multidrug-resistant (MDR) bacteria such as Pseudomonas aeruginosa are significant public health issues worldwide. A system biology approach can help understand bacterial behaviour and provide novel ways to identify potential therapeutic targets and develop new drugs. Gene regulatory networks (GRN) are examples of in silico representation of interaction between regulatory genes and their targets.
View Article and Find Full Text PDFis an opportunistic human pathogen that has been a constant global health problem due to its ability to cause infection at different body sites and its resistance to a broad spectrum of clinically available antibiotics. The World Health Organization classified multidrug-resistant among the top-ranked organisms that require urgent research and development of effective therapeutic options. Several approaches have been taken to achieve these goals, but they all depend on discovering potential drug targets.
View Article and Find Full Text PDFBird migration is typically associated with a latitudinal movement from north to south and vice versa. However, many bird species migrate seasonally with an upslope or downslope movement in a process termed altitudinal migration. Globally, 830 of the 6,579 Passeriformes species are considered altitudinal migrants and this pattern has emerged multiple times across 77 families of this order.
View Article and Find Full Text PDFBackground: Intimin is an important virulence factor involved in the pathogenesis of enteropathogenic Escherichia coli (EPEC) and enterohemorrhagic Escherichia coli (EHEC). Both pathogens are still important causes of diarrhea in children and adults in many developing and industrialized countries. Considering the fact that antibodies are important tools in the detection of various pathogens, an anti-intimin IgG2b monoclonal antibody was previously raised in immunized mice with the conserved sequence of the intimin molecule (int388-667).
View Article and Find Full Text PDFThe phytochemical investigation of Dimerostemma arnottii (Asteraceae) afforded, in addition to a known eudesmanolide, two unusual eudesmane methyl ester derivatives and a new eudesmanolide. Structural elucidation of the compounds was based on their 1D and 2D NMR spectroscopic as well as HR-ESI-MS data. There is a remarkable similarity between the structures of the eudesmanes from D.
View Article and Find Full Text PDFThe cell's cytoplasm is crowded by its various molecular components, resulting in a limited solvent capacity for the allocation of new proteins, thus constraining various cellular processes such as metabolism. Here we study the impact of the limited solvent capacity constraint on the metabolic rate, enzyme activities, and metabolite concentrations using a computational model of Saccharomyces cerevisiae glycolysis as a case study. We show that given the limited solvent capacity constraint, the optimal enzyme activities and the metabolite concentrations necessary to achieve a maximum rate of glycolysis are in agreement with their experimentally measured values.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
October 2007
Emerging infectious diseases are among the main threats to conservation of biological diversity. A crucial task facing epidemiologists is to predict the vulnerability of populations of endangered animals to disease outbreaks. In this context, the network structure of social interactions within animal populations may affect disease spreading.
View Article and Find Full Text PDFFEMS Immunol Med Microbiol
November 2007
Proteus mirabilis is an important cause of urinary tract infection (UTI) in patients with complicated urinary tracts. Thirty-five strains of P. mirabilis isolated from UTI were examined for the adherence capacity to epithelial cells.
View Article and Find Full Text PDFOBJECTIVE: This article aims at reviewing one of the most important problems faced by pediatricians in the field of child neurology. The paroxystic non-epileptic events are also a frequent reason for pediatric neurology consultations and admission for diagnostic videoelectroencephalogram monitoring. SOURCES: Literature review on the subject was perform on Medline, data were also collected from the main Pediatric Neurology Textbooks, which were found to be an important and unique source of information on the subject.
View Article and Find Full Text PDFPhys Rev E Stat Nonlin Soft Matter Phys
October 2002
We study the static and dynamic behavior of the one dimensional pair contact process with diffusion. Several critical exponents are found to vary with the diffusion rate, while the order-parameter moment ratio m=rho(2);/rho;(2) grows logarithmically with system size. The anomalous behavior of m is traced to a violation of scaling in the order parameter probability density, which in turn reflects the presence of two distinct sectors, one purely diffusive, the other reactive, within the active phase.
View Article and Find Full Text PDFPurpose: Few reports detailing the electroclinical features of epileptic spasms persisting beyond infancy have been published. We sought to characterize this unique population further.
Methods: We retrospectively reviewed the clinical and video-EEG data on 26 patients (4-17 years; mean, 93 months) with a confirmed diagnosis of epileptic spasms and who were evaluated at our tertiary referral center between 1993 and 2000.