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41.
Eneda Pjetri Ria de Haas Simone de Jong Cigdem Gelegen Hugo Oppelaar Linda A. W. Verhagen Marinus J. C. Eijkemans Roger A. Adan Berend Olivier Martien J. Kas 《PloS one》2012,7(11)
Animal studies are very useful in detection of early disease indicators and in unravelling the pathophysiological processes underlying core psychiatric disorder phenotypes. Early indicators are critical for preventive and efficient treatment of progressive psychiatric disorders like anorexia nervosa. Comparable to physical hyperactivity observed in anorexia nervosa patients, in the activity-based anorexia rodent model, mice and rats express paradoxical high voluntary wheel running activity levels when food restricted. Eleven inbred mouse strains and outbred Wistar WU rats were exposed to the activity-based anorexia model in search of identifying susceptibility predictors. Body weight, food intake and wheel running activity levels of each individual mouse and rat were measured. Mouse strains and rats with high wheel running activity levels during food restriction exhibited accelerated body weight loss. Linear mixed models for repeated measures analysis showed that baseline wheel running activity levels preceding the scheduled food restriction phase strongly predicted activity-based anorexia susceptibility (mice: Beta = −0.0158 (±0.003 SE), P<0.0001; rats: Beta = −0.0242 (±0.004 SE), P<0.0001) compared to other baseline parameters. These results suggest that physical activity levels play an important role in activity-based anorexia susceptibility in different rodent species with genetically diverse background. These findings support previous retrospective studies on physical activity levels in anorexia nervosa patients and indicate that pre-morbid physical activity levels could reflect an early indicator for disease severity. 相似文献
42.
Dispersal is a crucial ecological process, driving population dynamics and defining the structure and persistence of populations. Measuring demographic connectivity between discreet populations remains a long-standing challenge for most marine organisms because it involves tracking the movement of pelagic larvae. Recent studies demonstrate local connectivity of reef fish populations via the dispersal of planktonic larvae, while biogeography indicates some larvae must disperse 100–1000 s kilometres. To date, empirical measures of long-distance dispersal are lacking and the full scale of dispersal is unknown. Here we provide the first measure of long-distance dispersal in a coral reef fish, the Omani clownfish Amphiprion omanensis, throughout its entire species range. Using genetic assignment tests we demonstrate bidirectional exchange of first generation migrants, with subsequent social and reproductive integration, between two populations separated by over 400 km. Immigration was 5.4% and 0.7% in each region, suggesting a biased southward exchange, and matched predictions from a physically-coupled dispersal model. This rare opportunity to measure long-distance dispersal demonstrates connectivity of isolated marine populations over distances of 100 s of kilometres and provides a unique insight into the processes of biogeography, speciation and adaptation. 相似文献
43.
Background
The trade of plant roots as traditional medicine is an important source of income for many people around the world. Destructive harvesting practices threaten the existence of some plant species. Harvesters of medicinal roots identify the collected species according to their own folk taxonomies, but once the dried or powdered roots enter the chain of commercialization, accurate identification becomes more challenging.Methodology
A survey of morphological diversity among four root products traded in the medina of Marrakech was conducted. Fifty-one root samples were selected for molecular identification using DNA barcoding using three markers, trnH-psbA, rpoC1, and ITS. Sequences were searched using BLAST against a tailored reference database of Moroccan medicinal plants and their closest relatives submitted to NCBI GenBank.Principal Findings
Combining psbA-trnH, rpoC1, and ITS allowed the majority of the market samples to be identified to species level. Few of the species level barcoding identifications matched the scientific names given in the literature, including the most authoritative and widely cited pharmacopeia.Conclusions/Significance
The four root complexes selected from the medicinal plant products traded in Marrakech all comprise more than one species, but not those previously asserted. The findings have major implications for the monitoring of trade in endangered plant species as morphology-based species identifications alone may not be accurate. As a result, trade in certain species may be overestimated, whereas the commercialization of other species may not be recorded at all. 相似文献44.
Beta-galactosidase activity was studied as a possible cause of the low milk acidification ability observed in Lactobacillus reuteri NRRL 14171. Enzymatic activity was determined in MRS broth supplemented with either glucose or lactose and milk at the middle and final stage of the exponential phase, as well as at the stationary phase. Results were compared with beta-galactosidase activity in Lactobacillus casei NRRL-B1922, a strain that shows the milk acidification ability. The effects of the types of carbon and nitrogen sources were established by comparison of growth parameters (higher maximum cell concentration and specific growth rate) in broth culture and skim milk supplemented with 2% glucose or 1% casein peptone. In milk, L. reuteri showed higher beta-galactosidase activity in all growth phases compared with L. casei. Greater cell concentration maxima, specific growth rates, and acidification abilities were observed in L. reuteri when it was cultured in milk supplemented with 1% casein peptone compared with non-supplemented milk cultures. Results suggest that the poor milk acidification ability observed in L. reuteri may be more related to a weak proteolytic system than to deficient beta-galactosidase activity. 相似文献
45.
Francisco Amorim Orly Razgour Vanessa A. Mata Susana Lopes Raquel Godinho Carlos Ibáñez Javier Juste Stephen J. Rossiter Pedro Beja Hugo Rebelo 《Journal of Zoological Systematics and Evolutionary Research》2020,58(1):499-518
The Mediterranean Basin is a global biodiversity hotspot, hosting a number of native species belonging to families that are found almost exclusively in tropical climates. Yet, whether or not these taxa were able to survive in the Mediterranean region during the Quaternary climatic oscillations remains unknown. Focusing on the European free-tailed bat (Tadarida teniotis), we aimed to (a) identify potential ancient populations and glacial refugia; (b) determine the post-glacial colonization routes across the Mediterranean; and (c) evaluate current population structure and demography. Mitochondrial and nuclear markers were used to understand T. teniotis evolutionary and demographic history. We show that T. teniotis is likely restricted to the Western Palearctic, with mitochondrial phylogeny suggesting a split between an Anatolian/Middle East clade and a European clade. Nuclear data pointed to three genetic populations, one of which is an isolated and highly differentiated group in the Canary Islands, another distributed across Iberia, Morocco, and France, and a third stretching from Italy to the east, with admixture following a pattern of isolation by distance. Evolutionary and demographic reconstruction supports a pre-Last Glacial Maximum (LGM) colonization of Italy and the Anatolian/Middle East, while the remaining populations were colonized from Italy after the Younger Dryas. We also found support for demographic expansion following the Iberian colonization. The results show that during the LGM T. teniotis persisted in Mediterranean refugia and has subsequently expanded to its current circum-Mediterranean range. Our findings raise questions regarding the physiological and ecological traits that enabled species with tropical affinities to survive in colder climates. 相似文献
46.
Daniel Mota-Rojas Adriana Olmos-Hernndez Antonio Verduzco-Mendoza Hugo Lecona-Butrn Julio Martínez-Burnes Patricia Mora-Medina Jocelyn Gmez-Prado Agustín Orihuela 《Experimental Animals》2021,70(1):1
The science of animal welfare has evolved over the years, and recent scientific advances have enhanced our comprehension of the neurological, physiological, and ethological mechanisms of diverse animal species. Currently, the study of the affective states (emotions) of nonhuman animals is attracting great scientific interest focused primarily on negative experiences such as pain, fear, and suffering, which animals experience in different stages of their lives or during scientific research. Studies underway today seek to establish methods of evaluation that can accurately measure pain and then develop effective treatments for it, because the techniques available up to now are not sufficiently precise. One innovative technology that has recently been incorporated into veterinary medicine for the specific purpose of studying pain in animals is called infrared thermography (IRT), a technique that works by detecting and measuring levels of thermal radiation at different points on the body’s surface with high sensitivity. Changes in IRT images are associated mainly with blood perfusion, which is modulated by the mechanisms of vasodilatation and vasoconstriction. IRT is an efficient, noninvasive method for evaluating and controlling pain, two critical aspects of animal welfare in biomedical research. The aim of the present review is to compile and analyze studies of infrared thermographic changes associated with pain in laboratory research involving animals. 相似文献
47.
Wayllace NZ Valdez HA Merás A Ugalde RA Busi MV Gomez-Casati DF 《Molecular biology reports》2012,39(1):585-591
The metabolic pathways leading to the synthesis of bacterial glycogen involve the action of several enzymes, among which glycogen
synthase (GS) catalyzes the elongation of the α-1,4-glucan. GS from Agrobacterium tumefaciens uses preferentially ADPGlc, although UDPGlc can also be used as glycosyl donor with less efficiency. We present here a continuous
spectrophotometric assay for the determination of GS activity using ADP- or UDPGlc. When ADPGlc was used as the substrate,
the production of ADP is coupled to NADH oxidation via pyruvate kinase (PK) and lactate dehydrogenase (LDH). With UDPGlc as
substrate, UDP was converted to ADP via adenylate kinase and subsequent coupling to PK and LDH reactions. Using this assay,
we determined the kinetic parameters of GS and compared them with those obtained with the classical radiochemical method.
For this purpose, we improved the expression procedure of A. tumefaciens GS using Escherichia coli BL21(DE3)-RIL cells. This assay allows the continuous monitoring of glycosyltransferase activity using ADPGlc or UDPGlc as
sugar-nucleotide donors. 相似文献
48.
Rosete Pescador Gilberto Barbante Kerbauy Déborah Yara Alves Cursino dos Santos Lírio Luiz Dal Vesco Hugo Pacheco de Freitas Fraga Miguel Pedro Guerra 《Acta Physiologiae Plantarum》2012,34(2):771-778
Somatic embryogenesis is an in vitro morphogenetic route in which isolated cells or a small group of somatic cells give rise
to bipolar structures resembling zygotic embryos. Lipids, carbohydrates, and proteins are major compounds in plant and animal
metabolism. Comparative analysis along different developmental stages of Acca sellowiana (Myrtaceae) zygotic and somatic embryos, revealed a progressive increase in levels of total lipids. A high degree of similarity
could be found in the total lipids composition between A. sellowiana somatic and zygotic embryos. High lipid levels were found in zygotic embryos in the torpedo and cotyledonary stages, and
these levels increased according to the progression in the developmental stages. Somatic embryos obtained through direct embryogenesis
route showed higher levels of lipids than in indirect somatic embryogenesis. The compounds most frequently were linoleic acid
(C18:2), palmitic (C16:0) and oleic (C18:1). These results indicate a high similarity degree of accumulation of total lipids,
regardless of zygotic or somatic embryogenesis. 相似文献
49.
Rütgen BC Willenbrock S Reimann-Berg N Walter I Fuchs-Baumgartinger A Wagner S Kovacic B Essler SE Schwendenwein I Nolte I Saalmüller A Murua Escobar H 《PloS one》2012,7(6):e40078
Cell lines are key tools in cancer research allowing the generation of neoplasias in animal models resembling the initial tumours able to mimic the original neoplasias closely in vivo. Canine lymphoma is the major hematopoietic malignancy in dogs and considered as a valuable spontaneous large animal model for human Non-Hodgkin's Lymphoma (NHL). Herein we describe the establishment and characterisation of an in vivo model using the canine B-cell lymphoma cell line CLBL-1 analysing the stability of the induced tumours and the ability to resemble the original material. CLBL-1 was injected into Rag2(-/-)γ(c) (-/-) mice. The generated tumor material was analysed by immunophenotyping and histopathology and used to establish the cell line CLBL-1M. Both cell lines were karyotyped for detection of chromosomal aberrations. Additionally, CLBL-1 was stimulated with IL-2 and DSP30 as described for primary canine B-cell lymphomas and NHL to examine the stimulatory effect on cell proliferation. CLBL-1 in vivo application resulted in lymphoma-like disease and tumor formation. Immunophenotypic analysis of tumorous material showed expression of CD45(+), MHCII(+), CD11a(+) and CD79αcy(+). PARR analysis showed positivity for IgH indicating a monoclonal character. These cytogenetic, molecular, immunophenotypical and histological characterisations of the in vivo model reveal that the induced tumours and thereof generated cell line resemble closely the original material. After DSP30 and IL-2 stimulation, CLBL-1 showed to respond in the same way as primary material. The herein described CLBL-1 in vivo model provides a highly stable tool for B-cell lymphoma research in veterinary and human medicine allowing various further in vivo studies. 相似文献
50.
Aspergillus is a genus of mold fungi that includes more than 200 described species. Many members of the group are relevant pathogens and other species are economically important. Only one species has been analyzed for codon usage, and this was performed with a small number of genes. In this paper, we report the codon usage patterns of eight completely sequenced genomes which belong to this genus. The results suggest that selection for translational efficiency and accuracy are the major factors shaping codon usage in all of the species studied so far, and therefore they were active in the last common ancestor of the group. Composition and molecular distances analyses show that highly expressed genes evolve slower at synonymous sites. We identified a conserved core of translationally optimal codons and study the tRNA gene pool in each genome. We found that the great majority of preferred triplets match the respective cognate tRNA with more copies in the respective genome. We discuss the possible scenarios that can explain the observed differences among the species analyzed. Finally we highlight the biotechnological application of this research regarding heterologous protein expression. 相似文献