Search results for "Lost"

Allosteric modulation of nicotinic acetylcholine receptors as a treatment strategy for Alzheimer's disease

2000

The basic symptoms of Alzheimer's dementia, i.e., a loss in cognitive function, are due to impaired nicotinic cholinergic neurotransmission. To compensate for this impairment by drug treatment, blockers of the acetylcholine-degrading enzyme acetylcholinesterase are applied, even though this approach obviously is prone to many side-effects, including those of muscarinic nature. We have recently described a novel class of nicotinic acetylcholine receptor ligands which, similar to the action of benzodiazepines on GABA(A) receptors, allosterically potentiate submaximal nicotinic responses. The sensitizing effect is a consequence of facilitated channel opening in the presence of allosterically p…

Identification of acetyl-T-2 toxin, a trichothecene, in moldy rice by HPLC and FDMS

1982

Incidence and epidemiology of Citrus tristeza virus in the Valencian Community of Spain

2000

Abstract The first outbreak of citrus tristeza disease in Spain caused by Citrus tristeza virus (CTV) was recorded in 1957 in the Valencian Community (VC). In total c. 40 million trees, mainly of sweet orange and mandarin grafted on sour orange rootstocks, declined due to CTV. Large-scale surveys in different municipalities of the VC indicated that the disease spread very fast. Incidence increased from 11% in 1989 to 53% in 1998. Toxoptera aurantii and Aphis spiraecola (inefficient aphid vectors of CTV) predominated before 1985–87. Since then the relatively efficient vector Aphis gossypii has become dominant and induced an epidemic that has been modelled. The large number of A.gossypii that…

Variation of haplotype distributions of two genomic regions of Citrus tristeza virus populations from eastern Spain.

2003

Genetic variation in natural populations of Citrus tristeza virus (CTV) was studied using haplotypes detected by single-strand conformation polymorphism (SSCP) analysis of two genomic regions (p20 gene and segment A, located in ORF1a). Analysis of 254 samples from 125 trees, collected at 12 different sites, yielded 8 different haplotypes for p20 and 5 for segment A. The most frequent haplotype of p20 was predominant at all sites, but several sites differed in the predominance of segment A haplotypes. At most sites, the homozygosity observed for the p20 gene tended to be higher than expected in a neutral evolution, whereas the opposite was true for segment A. Comparison of the populations at…

Control of kinetics by cooperative interactions.

2011

Cooperative effects in ligand binding and dissociation kinetics are much less investigated than steady state kinetics or equilibrium binding. Nevertheless, cooperativity in ligand binding leads necessarily to characteristic properties with respect to kinetic properties of the system. In case of positive cooperativity as found in oxygen binding proteins, a typical property is an autocatalytic ligand dissociation behavior leading to a time dependent, apparent ligand dissociation rate. To follow systematically the influence of the various potentially involved parameters on this characteristic property, simulations based on the simple MWC model were performed which should be relevant for all ty…

Virulence-Associated Mobile Elements in Bacilli and Clostridia

2014

This chapter focuses on (i) species that induce human diseases, (ii) species that are able to produce toxins, and (iii) the association of appropriate virulence factors with possible mobile elements. With reference to bacilli, the chapter discusses mainly Bacillus anthracis and B. cereus. A section on clostridia focuses on Clostridium perfringens, neurotoxin-producing clostridia, and species capable of producing large clostridial cytotoxins (LCTs). The chapter talks about the contribution of the genetic mobility of virulence genes to the evolution of pathogenic bacilli and clostridia. B. anthracis strains produce a tripartite protein toxin, comprising PA (protective antigen), EF (edema fact…

Digestive disorders and Intestinal microbiota

2018

In the last decade, a barge body of scientific literature has suggested that specific alterations of the gut microbiota may be associated with ther development and clinical course of several gastrointestinal diseases, including irritable bowel syndrome, inflammatory bowel disease, celiac disease, gastrointestinal cancer and Clostridium difficile infection. These alterations are often referred to as “dysbiosis”, a generic term designing reduction of gut microbiota biodiversity and alterations in its composition. Here, we provide a synthetic overview of the key concepts on the relationship between intestinal microbiota and gastrointestinal diseases, focusing on the translation of these concep…

Clostridium difficile infekcijas gadījumu analīze stacionārā Latvijas Infektoloģijas Centrs

2016

Clostridium difficile slimību (CDI) skaits pēdējos gados dramatiski pieaug. Vienu no svarīgākajiem šīs problēmas aspektiem var atrisināt, ja tiks kvalitatīvi un kvantitatīvi izvērtēti iespējamie riska faktori, kas predisponē Clostridium difficile slimības attīstību. Pētījuma mērķis bija atrast nozares, kur tiek pārmērīgi izmantotas plaša spektra antibiotikas, kas veicina slimības incidences pieaugumu, kā arī novērtēt laboratorisko rādītāju izmaiņas atkarībā no slimības smaguma pakāpes. Retrospektīvā pētījuma laikā, tika analizētas 60 Latvijas Infektoloģijas centrā stacionētu pacientu medicīniskās kartes 2014.-2015. g. periodā, kuriem tika apstiprināta diagnoze – Clostridium difficile infekc…

Clostridium ģints baktēriju noteikšana dzeramajā ūdenī izmantojot Fluorescento in situ hibridizāciju

2015

Bakalaura darba mērķis bija ātri un precīzi identificēt dzeramajā ūdenī Clostridium ģints baktērijas izmantojot Fluorescento in situ hibridizāciju. Līdz ar to tika izmērīts un salīdzināts fluorescences intensitātes līmenis dažādām Clostridium sugām, kā arī citiem mikroorganismiem izmantojot Clostridium spp. specifiskas fluorescentās zondes. 92% no Clostridium acetobutylicum izmērītam šūnām, relatīvās gaismas vienības (RLU) pārsniedza 500 vienību robežu, 99% no Clostridium beijernickii un 96% no Clostridium tetahomorphum, salīdzinājumā ar Sphingomonas paucimobilis, kur tikai 2% pārsniedza 300 RLU. Veiktais variācijas analīzes tests (ANOVA) liecināja, ka starp Clostridium ģints baktērijām un …

Nucleotide sequence of Clostridium difficile toxin A.

1990