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51.
Pigs used in research are often housed in barren environments. The effects of ice as a simple enrichment tool for newly weaned pigs were investigated. Four replicates of 120 pigs were separated into 3 groups. One group was given free access to blocks of ice (ice group), another group had access to Classic Kong toys (Kong group), and a 3rd group did not receive any enrichment (control group). The behavior of each group was observed every 5 min from 08:00 hr to 12:00 hr during 4 consecutive days. Pigs were motivated to explore the ice blocks (4.85% ± 1.34) over the Classic Kong toys (2.03% ± 0.59). No differences in other behaviors were found between treatments. Ice is an effective and easy-to-replace enrichment device. Blocks of ice can be used as enrichment devices for pigs housed in research facilities. 相似文献
52.
Vanessa I. Rohlf Samia Toukhsati Grahame J. Coleman Pauleen C. Bennett 《Journal of applied animal welfare science : JAAWS》2013,16(3):213-236
Dog obesity is a common nutritional disorder affecting up to 40% of the companion animal (pet) dog population in Australia and other developed nations. A clear understanding of factors determining relevant caregiver (owner) behaviors underpins effective treatment for this disorder. The theory of planned behavior can be used to understand factors contributing to human behavior. This article describes research informed by this theory. The research examined relationships between owners' behavioral beliefs and barriers, normative beliefs and perceptions of control, owners' feeding and exercise behaviors toward their dogs, and the body condition scores (BCSs) of dogs. The study recruited a sample of 182 dog and owner dyads. The researcher independently assessed BCSs. Owners completed a questionnaire measuring relevant feeding and exercise beliefs and behaviors. This revealed significant correlations between many psychological variables and BCSs and between psychological variables and specific owner behaviors: for example, the relationship of low levels of intentions to feed appropriately to ambivalent beliefs toward feeding appropriately and low perceived control. Careful consideration of the specific variables identified will permit the development of more effective interventions. 相似文献
53.
Vanessa Pitozzi Stefania Pallotta Manuela Balzi Marta Bucciolini Aldo Becciolini Piero Dolara 《Free radical research》2013,47(11):1149-1154
We used X-rays from a linear accelerator and from a low energy therapeutic source to calibrate the single cell gel electrophoresis (comet assay), a widely used method to measure DNA damage. γ-Rays from 60Co, with known efficiency in inducing DNA breakage, were used as reference. Human lymphocytes and one murine tumour cell line, F10-M3 cells, were irradiated under different experimental conditions. A similar relationship between radiation dose and induced DNA damage was obtained with γ- and X-rays. A calibration curve was constructed to convert the comet assay raw data into break frequency. The median levels of DNA breaks and oxidative damage in circulating lymphocytes from healthy volunteers were calculated to be 0.76 and 0.80 breaks/109 Da, respectively, (0.50 and 0.52 breaks/106 bp). The values of oxidative DNA damage were in the same order of magnitude as those found by others with HPLC methods. 相似文献
54.
Vanessa Gonzalez‐Covarrubias Marian Beekman Hae‐Won Uh Adrie Dane Jorne Troost Iryna Paliukhovich Frans M. van der Kloet Jeanine Houwing‐Duistermaat Rob J. Vreeken Thomas Hankemeier Eline P. Slagboom 《Aging cell》2013,12(3):426-434
Middle‐aged offspring of nonagenarians, as compared to their spouses (controls), show a favorable lipid metabolism marked by larger LDL particle size in men and lower total triglyceride levels in women. To investigate which specific lipids associate with familial longevity, we explore the plasma lipidome by measuring 128 lipid species using liquid chromatography coupled to mass spectrometry in 1526 offspring of nonagenarians (59 years ± 6.6) and 675 (59 years ± 7.4) controls from the Leiden Longevity Study. In men, no significant differences were observed between offspring and controls. In women, however, 19 lipid species associated with familial longevity. Female offspring showed higher levels of ether phosphocholine (PC) and sphingomyelin (SM) species (3.5–8.7%) and lower levels of phosphoethanolamine PE (38:6) and long‐chain triglycerides (TG) (9.4–12.4%). The association with familial longevity of two ether PC and four SM species was independent of total triglyceride levels. In addition, the longevity‐associated lipid profile was characterized by a higher ratio of monounsaturated (MUFA) over polyunsaturated (PUFA) lipid species, suggesting that female offspring have a plasma lipidome less prone to oxidative stress. Ether PC and SM species were identified as novel longevity markers in females, independent of total triglycerides levels. Several longevity‐associated lipids correlated with a lower risk of hypertension and diabetes in the Leiden Longevity Study cohort. This sex‐specific lipid signature marks familial longevity and may suggest a plasma lipidome with a better antioxidant capacity, lower lipid peroxidation and inflammatory precursors, and an efficient beta‐oxidation function. 相似文献
55.
Stella Manta Vanessa Parmenopoulou Christos Kiritsis Athina Dimopoulou Nikolaos Kollatos Ioannis Papasotiriou 《Nucleosides, nucleotides & nucleic acids》2013,32(7):522-535
This article describes the synthesis of (3 ′S) and (3 ′R)-3 ′-amino-3 ′-deoxy pyranonucleosides and their precursors (3 ′S) and (3 ′R)-3 ′-azido-3 ′-deoxy pyranonucleosides. Azidation of 1,2:5,6-di-O-isopropylidene-3-O-toluenesulfonyl-α-D-allofuranose followed by hydrolysis and subsequent acetylation afforded 3-azido-3-deoxy-1,2,4,6-tetra-O-acetyl-D-glucopyranose, which upon coupling with the proper silylated bases, deacetylation, and catalytic hydrogenation, obtained the target 3 ′-amino-3 ′-deoxy-β-D-glucopyranonucleosides. The desired 1-(3 ′-amino-3 ′-deoxy-β-D-allopyranosyl)5-fluorouracil was readily prepared from the suitable imidazylate sugar after azidation followed by a protection/deprotection sequence and reduction of the unprotected azido precursor. No antiviral activity was observed for the novel nucleosides. Moderate cytostatic activity was recorded for the 5-fluorouracil derivatives. 相似文献
56.
Vanessa Dutra Silva Jeferson Schneider Carletto Eduardo Carasek Boris Ugarte Stambuk Maria da Graça Nascimento 《Process Biochemistry》2013,48(8):1159-1165
The α,β-unsaturated carbonyl compound (4S)-(+)-carvone was selectively reduced to (1R,2R,4S)-iso-dihydrocarveol using baker's yeasts. The conversion of the bioreduction reaction was monitored using a green hollow-fiber liquid–liquid–liquid microextraction (HF-LLLME) technique. Several parameters which may affect the bioreduction of (4S)-(+)-carvone, such as temperature, time, substrate/enzyme ratio, pH and buffer concentration, were evaluated. The effect of some additives, such as trehalose, DMSO and the ionic liquid [BMIm][PF6], was also studied. The (1R,2R,4S)-iso-dihydrocarveol was recovered with 52.7% conversion and diastereoisomeric excess >99% after 48 h of reaction at 40 °C in an aqueous monophasic system, with 0.1 mol L?1 buffer concentration (pH 7.5) and a substrate/yeast cell mass ratio of 8.0 mg g?1. The HF-LLLME microextraction technique allowed the optimization of the reaction with a reduction of over 99.5% in relation to the use of organic solvents. 相似文献
57.
58.
Marcelo de Oliveira Barbosa Rubens Rodrigues da Silva Vanessa Carolina de Sena Correia Luana Pereira dos Santos Analía del Valle Garnero Ricardo José Gunski 《Genetics and molecular biology》2013,36(1):70-73
Cytogenetic studies in birds are still scarce compared to other vertebrates. Woodcreepers (Dendrocolaptidae) are part of a highly specialized group within the Suboscines of the New World. They are forest birds exclusive to the Neotropical region and similar to woodpeckers, at a comparable evolutionary stage. This paper describes for the first time the karyotypes of the Olivaceous and the Narrow-billed Woodcreeper using conventional staining with Giemsa and silver nitrate staining of the nucleolar organizer regions (Ag-NORs). Metaphases were obtained by fibular bone marrow culture. The chromosome number of the Olivaceous Woodcreeper was 2n = 82 and of the Narrow-billed Woodcreeper, 2n = 82. Ag-NORs in the largest macrochromosome pair and evidence of a chromosome inversion are described herein for the first time for this group. 相似文献
59.
Jamie Bryant Vanessa M McDonald Allison Boyes Rob Sanson-Fisher Christine Paul Jessica Melville 《Respiratory research》2013,14(1):109
Adherence to medication among individuals with chronic obstructive pulmonary disease (COPD) is suboptimal and has negative impacts on survival and health care costs. No systematic review has examined the effectiveness of interventions designed to improve medication adherence. Electronic databases Medline and Cochrane were searched using a combination of MeSH and keywords. Eligible studies were interventions with a primary or secondary aim to improve medication adherence among individuals with COPD published in English. Included studies were assessed for methodological quality using the Effective Practice and Organisation of Care (EPOC) criteria. Of the 1,186 papers identified, seven studies met inclusion criteria. Methodological quality of the studies was variable. Five studies identified effective interventions. Strategies included: brief counselling; monitoring and feedback about inhaler use through electronic medication delivery devices; and multi-component interventions consisting of self-management and care co-ordination delivered by pharmacists and primary care teams. Further research is needed to establish the most effective and cost effective interventions. Special attention should be given to increasing patient sample size and using a common measure of adherence to overcome methodological limitations. Interventions that involve caregivers and target the healthcare provider as well as the patient should be further explored. 相似文献
60.
Matthew Maddocks Vanessa Halliday Alpna Chauhan Victoria Taylor Annmarie Nelson Cathy Sampson Anthony Byrne Gareth Griffiths Andrew Wilcock 《PloS one》2013,8(12)