120 research outputs found

    Розробка та валідація ГРХ/МС-методики кількісного визначення доксиламіну

    Get PDF
    Doxylamine is a hypnotic medicine used for treatment of minor sleep disorders and is a frequent cause of poisoning.Aim. To develop GLC/MS-procedure of doxylamine quantification and carry out step-by-step validation ofthe developed procedure in the variants of the method of calibration curve, method of standard and method of additions.Results. The chromatographic conditions have been chosen for doxylamine determination by the method of GLC with mass-spectrometry detection with temperature program changing during the analysis from 70 °C to 320 °C. Retention time for doxylamine is 14.53 min. To prove the possibility of the proposed procedure application in further analysis its validation has been carried out in the variants of the method of calibration curve, method of standard and method of additions. Such validation parameters as in process stability, linearity, accuracy, precision and limit of determination have been estimated by model solutions.Experimental part. Conditions of chromatographic analysis: Agilent 6890N/5973N/7683; НР-5MS ∅0.25 mm × 30 m, 0.25 μm; DB-17MS ∅0.25 mm × 30 m, 0.15 μm; columns are connected sequentially through Deans switch; thermostat – 70 CºС (2 min), 45 ºС/min to 210 ºС, 6 ºС/min to 320 ºС (12.56 min); transfer line – 280 ºС; ion source – 230 ºС; quadrupole – 150 ºС; electron impact, 70eV; 40 – 750 m/z; injector – 250 ºС; splitless mode; inlet carrier gas (helium) pressure: 1st column – 26.06 psi, 2nd column – 19.30 psi.Conclusions. New procedure of doxylamine quantitative determination by the method of GLC/MS has been developed. Its validation has been carried out and acceptability for application has been shown.Доксиламин – снотворный препарат, который применяется для лечения легких незначительных расстройств сна и является частой причиной отравлений.Цель. Разработать ГЖХ/МС-методику количественного определения доксиламина и провести поэтапную валидацию разработанной методики в вариантах метода калибровочного графика, метода стандарта и метода добавок.Результаты. Для определения доксиламина методом ГЖХ с использованием масс-спектрометрической детекции были подобраны хроматографические условия с программируемым изменением температуры от 70 °С до 320 °С в процессе анализа. Время удерживания для секнидазола составляет 14,53 мин. Для доказательства возможности применения предлагаемых методик в дальнейшем анализе была проведена их валидация в вариантах метода калибровочного графика, метода стандарта и метода добавок. Такие валидационные параметры, как стабильность, линейность, правильность, прецизионность ипредел количественного определения были оценены с помощью модельных растворов.Экспериментальная часть. Условия хроматографирования: Agilent 6890N/5973N/7683; НР-5МС ∅0,25 мм × 30 м, 0,25 мкм; DB-17MS ∅0,25 мм × 30 м, 0,15 мкм; колонки подключены последовательно через переключатель Дина; термостат – 70 ºС (2 мин), 45 ºС/мин. до 210 ºС, 6 ºС/мин до 320 ºС (12,56 мин); интерфейс масс-спектрометра – 280 ºС; источник ионов – 230 ºС; квадруполь – 150 ºС; электронный удар, 70 эВ; 40 – 750 m/z; инжектор – 250 ºС; без разделения потока; давление газа-носителя (гелия) на входе: 1-я колонка – 26,06 psi, 2-я колонка – 19,30 psi.Выводы. Разработана новая методика количественного определения доксиламина методом ГЖХ/МС. Проведена ее валидация и показана приемлемость для применения.Доксиламін – снодійний лікарський засіб, що застосовується для лікування легких незначних розладів сну та є частою причиною отруєнь.Мета. Розробити ГРХ/МС-методику кількісного визначення доксиламіну та провести поетапну валідацію розробленої методики у варіантах методу калібрувального графіка, методу стандарту та методу добавок.Результати. Для визначення доксиламіну методом ГРХ з використанням мас-спектрометричного детектування були підібрані хроматографічні умови з програмованою зміною температури від 70 °С до 320 °С в процесі аналізу. Час утримування для доксиламіну становить 14,53 хв. Для доведення можливості застосування запропонованих методик у подальшому аналізі було проведено їх валідацію у варіантах методу калібрувального графіка, методу стандарту та методу добавок. Такі валідаційні параметри, як стабільність, лінійність, правильність, прецизійність і межа кількісного визначення було оцінено за допомогою модельних розчинів.Експериментальна частина. Умови хроматографування: Agilent 6890N/5973N/7683; НР-5МС ∅0,25 мм × 30 м, 0,25 мкм; DB-17MS ∅0,25 мм × 30 м, 0,15 мкм; колонки підключено послідовно через перемикач Діна; термостат – 70 ºС (2 хв), 45 ºС/хв до 210 ºС, 6 ºС/хв до 320 ºС (12,56 хв); інтерфейс мас-спектрометра – 280 ºС; джерело іонів – 230 ºС; квадруполь – 150 ºС; електронний удар, 70 еВ; 40 – 750 m/z; інжектор – 250 ºС; без розділення потоку; тиск газу-носія (гелію) на вході: 1-а колонка – 26,06 psi, 2-а колонка – 19,30 psi.Висновки. Розроблено нову методику кількісного визначення доксиламіну методом ГРХ/МС. Проведено її валідацію і показано прийнятність для застосування

    On selection of foxes for enhanced aggressiveness and its correlated implications

    Get PDF
    The results of a 35-year selection of foxes for aggressive response to humans are reported. Averaged estimates of the phenotypic manifestation of aggressiveness in all selection generations are presented. The dynamics of these estimates shows that the phenotypic response to the selection was obvious only in the first 12 generations. Subsequent selection did not alter the mean aggressiveness score. Analysis of variance was performed for the intergroup variability (among descendants of different mothers) and intragroup variability (among the offspring within a family). The intragroup variability was constantly low. Most likely, the trait is stabilized by maternal prenatal and early neonatal factors. The general tendency in the dynamics of intergroup variability is that it does not decrease over time during selection, no matter how long the population has been under it. It follows from the statistical indices of the phenotypic similarity between parents and offspring that additive interactions are insufficient for the explanation of the persisting variability. The contribution of epistatic interactions is not ruled out, though. Emphasis is laid on the correlated consequences of the selection for aggressiveness and their coordination with the consequences of the selection in the opposite direction, for elimination of aggressive response to humans, or for tameness. The parallelism of correlated changes in the selection in contrasting directions is illustrated by the examples of some physiological and morphological traits. The phenomenon is discussed in the light of classical notions of the resource of cryptic genetic variation and the role of selection in its phenotypic manifestation. Its interpretation also invokes molecular data pointing that some genetic pathways may regulate parameters of both aggression and tameness and that the selection processes in both directions may have some genetic targets in common

    Effects of experimental domestication of silver foxes (Vulpes vulpes) on vocal behaviour

    Get PDF
    This paper systematizes and generalizes a research cycle devoted to studying the acoustics and vocal behaviour of silver foxes that differ in their tolerance to humans. The research revealed that 50-year selection for tameness toward people resulted in selective use by Tame foxes toward humans of two call types, pant and cackle. At the same time, the selected for aggression toward people Aggressive foxes and the non-selected for behaviour Control foxes, selectively use toward humans cough and snort. Thus, call types representing vocal indicators of friendly and aggressive behaviour of foxes toward humans have been revealed by the research. Nevertheless, experimental domestication did not change vocal behaviour of foxes toward conspecifics; all three strains did not differ by their vocal behaviour toward same-strain silver foxes. Relationship has been investigated between vocal behaviour and degree of tolerance toward people for hybrids between Tame and Aggressive foxes and for backcrosses to Tame and Aggressive foxes. Effect was estimated between fox sex and the degree of human impact on focal fox for variables of fox vocal behaviour. The research revealed the universal for mammals vocal indicators of emotional arousal that are independent of the emotional valence. Characteristics of vocal behaviour that are related with positive and negative emotional valence have been revealed. A simple and effective method for estimating animal discomfort based on ”joint calls” that takes into account the characteristics of all calls irrespective of their acoustic structure has been revealed. The obtained results provide a basis for further comparative studies of the acoustic structure and vocal behaviour for other taxa of the genus Vulpes and the related canid genera (Canis, Cuon, Lycaon)

    Sequence comparison of prefrontal cortical brain transcriptome from a tame and an aggressive silver fox (Vulpes vulpes)

    Get PDF
    <p>Abstract</p> <p>Background</p> <p>Two strains of the silver fox (<it>Vulpes vulpes</it>), with markedly different behavioral phenotypes, have been developed by long-term selection for behavior. Foxes from the tame strain exhibit friendly behavior towards humans, paralleling the sociability of canine puppies, whereas foxes from the aggressive strain are defensive and exhibit aggression to humans. To understand the genetic differences underlying these behavioral phenotypes fox-specific genomic resources are needed.</p> <p>Results</p> <p>cDNA from mRNA from pre-frontal cortex of a tame and an aggressive fox was sequenced using the Roche 454 FLX Titanium platform (> 2.5 million reads & 0.9 Gbase of tame fox sequence; >3.3 million reads & 1.2 Gbase of aggressive fox sequence). Over 80% of the fox reads were assembled into contigs. Mapping fox reads against the fox transcriptome assembly and the dog genome identified over 30,000 high confidence fox-specific SNPs. Fox transcripts for approximately 14,000 genes were identified using SwissProt and the dog RefSeq databases. An at least 2-fold expression difference between the two samples (p < 0.05) was observed for 335 genes, fewer than 3% of the total number of genes identified in the fox transcriptome.</p> <p>Conclusions</p> <p>Transcriptome sequencing significantly expanded genomic resources available for the fox, a species without a sequenced genome. In a very cost efficient manner this yielded a large number of fox-specific SNP markers for genetic studies and provided significant insights into the gene expression profile of the fox pre-frontal cortex; expression differences between the two fox samples; and a catalogue of potentially important gene-specific sequence variants. This result demonstrates the utility of this approach for developing genomic resources in species with limited genomic information.</p

    The Red Fox Y-Chromosome in Comparative Context

    Get PDF
    While the number of mammalian genome assemblies has proliferated, Y-chromosome assemblies have lagged behind. This discrepancy is caused by biological features of the Y-chromosome, such as its high repeat content, that present challenges to assembly with short-read, next-generation sequencing technologies. Partial Y-chromosome assemblies have been developed for the cat (Felis catus), dog (Canis lupus familiaris), and grey wolf (Canis lupus lupus), providing the opportunity to examine the red fox (Vulpes vulpes) Y-chromosome in the context of closely related species. Here we present a data-driven approach to identifying Y-chromosome sequence among the scaffolds that comprise the short-read assembled red fox genome. First, scaffolds containing genes found on the Y-chromosomes of cats, dogs, and wolves were identified. Next, analysis of the resequenced genomes of 15 male and 15 female foxes revealed scaffolds containing male-specific k-mers and patterns of inter-sex copy number variation consistent with the heterogametic chromosome. Analyzing variation across these two metrics revealed 171 scaffolds containing 3.37 Mbp of putative Y-chromosome sequence. The gene content of these scaffolds is consistent overall with that of the Y-chromosome in other carnivore species, though the red fox Y-chromosome carries more copies of BCORY2 and UBE1Y than has been reported in related species and fewer copies of SRY than in other canids. The assignment of these scaffolds to the Y-chromosome serves to further characterize the content of the red fox draft genome while providing resources for future analyses of canid Y-chromosome evolution

    EquiFACS: the Equine Facial Action Coding System

    Get PDF
    Although previous studies of horses have investigated their facial expressions in specific contexts, e.g. pain, until now there has been no methodology available that documents all the possible facial movements of the horse and provides a way to record all potential facial configurations. This is essential for an objective description of horse facial expressions across a range of contexts that reflect different emotional states. Facial Action Coding Systems (FACS) provide a systematic methodology of identifying and coding facial expressions on the basis of underlying facial musculature and muscle movement. FACS are anatomically based and document all possible facial movements rather than a configuration of movements associated with a particular situation. Consequently, FACS can be applied as a tool for a wide range of research questions. We developed FACS for the domestic horse (Equus caballus) through anatomical investigation of the underlying musculature and subsequent analysis of naturally occurring behaviour captured on high quality video. Discrete facial movements were identified and described in terms of the underlying muscle contractions, in correspondence with previous FACS systems. The reliability of others to be able to learn this system (EquiFACS) and consistently code behavioural sequences was high—and this included people with no previous experience of horses. A wide range of facial movements were identified, including many that are also seen in primates and other domestic animals (dogs and cats). EquiFACS provides a method that can now be used to document the facial movements associated with different social contexts and thus to address questions relevant to understanding social cognition and comparative psychology, as well as informing current veterinary and animal welfare practices

    Construction of Red Fox Chromosomal Fragments from the Short-Read Genome Assembly

    Get PDF
    The genome of a red fox (Vulpes vulpes) was recently sequenced and assembled using next-generation sequencing (NGS). The assembly is of high quality, with 94X coverage and a scaffold N50 of 11.8 Mbp, but is split into 676,878 scaffolds, some of which are likely to contain assembly errors. Fragmentation and misassembly hinder accurate gene prediction and downstream analysis such as the identification of loci under selection. Therefore, assembly of the genome into chromosome-scale fragments was an important step towards developing this genomic model. Scaffolds from the assembly were aligned to the dog reference genome and compared to the alignment of an outgroup genome (cat) against the dog to identify syntenic sequences among species. The program Reference-Assisted Chromosome Assembly (RACA) then integrated the comparative alignment with the mapping of the raw sequencing reads generated during assembly against the fox scaffolds. The 128 sequence fragments RACA assembled were compared to the fox meiotic linkage map to guide the construction of 40 chromosomal fragments. This computational approach to assembly was facilitated by prior research in comparative mammalian genomics, and the continued improvement of the red fox genome can in turn offer insight into canid and carnivore chromosome evolution. This assembly is also necessary for advancing genetic research in foxes and other canids

    Dog breed differences in visual communication with humans

    Get PDF
    Domestic dogs (Canis familiaris) have developed a close relationship with humans through the process of domestication. In human-dog interactions, eye contact is a key element of relationship initiation and maintenance. Previous studies have suggested that canine ability to produce human-directed communicative signals is influenced by domestication history, from wolves to dogs, as well as by recent breed selection for particular working purposes. To test the genetic basis for such abilities in purebred dogs, we examined gazing behavior towards humans using two types of behavioral experiments: the `visual contact task' and the `unsolvable task'. A total of 125 dogs participated in the study. Based on the genetic relatedness among breeds subjects were classified into five breed groups: Ancient, Herding, Hunting, Retriever-Mastiff and Working). We found that it took longer time for Ancient breeds to make an eye-contact with humans, and that they gazed at humans for shorter periods of time than any other breed group in the unsolvable situation. Our findings suggest that spontaneous gaze behavior towards humans is associated with genetic similarity to wolves rather than with recent selective pressure to create particular working breeds

    A Method to Quantify Mouse Coat-Color Proportions

    Get PDF
    Coat-color proportions and patterns in mice are used as assays for many processes such as transgene expression, chimerism, and epigenetics. In many studies, coat-color readouts are estimated from subjective scoring of individual mice. Here we show a method by which mouse coat color is quantified as the proportion of coat shown in one or more digital images. We use the yellow-agouti mouse model of epigenetic variegation to demonstrate this method. We apply this method to live mice using a conventional digital camera for data collection. We use a raster graphics editing program to convert agouti regions of the coat to a standard, uniform, brown color and the yellow regions of the coat to a standard, uniform, yellow color. We use a second program to quantify the proportions of these standard colors. This method provides quantification that relates directly to the visual appearance of the live animal. It also provides an objective analysis with a traceable record, and it should allow for precise comparisons of mouse coats and mouse cohorts within and between studies

    Self domestication and the evolution of language

    Get PDF
    corecore