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471.
Michelle R. Kneeland Vincent A. Spagnuolo David C. Evers James D. Paruk Lee Attix Nina Schoch Mark A. Pokras Virginia Stout Alex Dalton Katy Silber 《Zoo biology》2020,39(4):263-270
Common loons (Gavia immer) are diving waterbirds that are particularly challenging to keep in captivity due to their specific behavioral and physiologic needs, special housing requirements, and susceptibility to stress-related disease. We report a novel method for housing and captive rearing common loon chicks that was developed as part of the first-ever loon translocation effort in southeast Massachusetts, from 2015 to 2017. Thirteen loon chicks were reared in aquatic pens in a natural lake environment, utilizing noninvasive feeding and monitoring techniques that avoided human habituation. Chicks were reared in aquatic pens for 16–28 days before being released onto the lake. All chicks remained clinically normal and were monitored on the lake for up to 4 months following release. At least four of the chicks were subsequently confirmed to have survived to adulthood when they returned to the area in breeding plumage two to 3 years following release. Two of these confirmed adults displayed prolonged territorial pair behavior together, and this is an encouraging early sign that captive-reared individuals may form successful breeding pairs in the future. Because most immature loons remain on the ocean until at least 3 years of age, we expect additional captive-reared loons to return to the release area in subsequent years. These husbandry techniques could be applied to other loon and diving bird species that are notoriously difficult to house in captivity. The novel feeding techniques described here could also be adapted for loon chicks being reared in pools or other traditional captive settings. 相似文献
472.
Lucy H. R. Whitaker Jen Reid Alex Choa Stuart McFee Marta Seretny John Wilson Rob A. Elton Katy Vincent Andrew W. Horne 《PloS one》2016,11(4)
Chronic pelvic pain (CPP) affects 5.7–26.6% women worldwide. 55% have no obvious pathology and 40% have associated endometriosis. Neuropathic pain (NeP) is pain arising as a consequence of a lesion/disease affecting the somatosensory system. The prevalence of NeP in women with CPP is not known. The diagnosis of NeP is challenging because there is no gold-standard assessment. Questionnaires have been used in the clinical setting to diagnose NeP in other chronic pain conditions and quantitative sensory testing (QST) has been used in a research setting to identify abnormal sensory function. We aimed to determine if women with chronic pelvic pain (CPP) have a neuropathic pain (NeP) component to their painful symptoms and how this is best assessed. We performed an exploratory prospective cohort study of 72 pre-menopausal women with a diagnosis of CPP. They underwent a clinician completed questionnaire (DN4) and completed the S-LANSS and PainDETECT™ questionnaires. Additionally QST testing was performed by a clinician. They also completed a patient acceptability questionnaire. Clinical features of NeP were identified by both questionnaires and QST. Of the women who were NeP positive, 56%, 35% and 26% were identified by the S-LANSS, DN4 and PainDETECT™ respectively. When NeP was identified by questionnaire, the associated laparoscopy findings were similar irrespective of which questionnaire was used. No subject had entirely unchanged QST parameters. There were distinct loss and gain subgroups, as well as mixed alteration in function, but this was not necessarily clinically significant in all patients. 80% of patients were confident that questionnaires could diagnose NeP, and 90% found them easy to complete. Early identification of NeP in women with CPP with a simple questionnaire could facilitate targeted therapy with neuromodulators, which are cheap, readily available, and have good safety profiles. This approach could prevent unnecessary or fertility-compromising surgery and prolonged treatment with hormones. 相似文献
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Albino Bacolla Xiao Zhu Hanning Chen Katy Howells David N. Cooper Karen M. Vasquez 《Nucleic acids research》2015,43(10):5065-5080
Single base substitutions (SBSs) and insertions/deletions are critical for generating population diversity and can lead both to inherited disease and cancer. Whereas on a genome-wide scale SBSs are influenced by cellular factors, on a fine scale SBSs are influenced by the local DNA sequence-context, although the role of flanking sequence is often unclear. Herein, we used bioinformatics, molecular dynamics and hybrid quantum mechanics/molecular mechanics to analyze sequence context-dependent mutagenesis at mononucleotide repeats (A-tracts and G-tracts) in human population variation and in cancer genomes. SBSs and insertions/deletions occur predominantly at the first and last base-pairs of A-tracts, whereas they are concentrated at the second and third base-pairs in G-tracts. These positions correspond to the most flexible sites along A-tracts, and to sites where a ‘hole’, generated by the loss of an electron through oxidation, is most likely to be localized in G-tracts. For A-tracts, most SBSs occur in the direction of the base-pair flanking the tracts. We conclude that intrinsic features of local DNA structure, i.e. base-pair flexibility and charge transfer, render specific nucleotides along mononucleotide runs susceptible to base modification, which then yields mutations. Thus, local DNA dynamics contributes to phenotypic variation and disease in the human population. 相似文献
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It has previously been shown that the ability of the chick toassociate the consumption of novel flavoured substances withsubsequent malaise is specific to the mode of ingestion (Gilletteet al., 1980), i.e., chicks will readily form conditioned aversionsto weakly flavoured solutions but not to relatively stronglyflavoured foods. The present series of four experiments indicatedthat the failure of chicks to develop conditioned aversionsto flavoured food is not due to the parameters of flavour intensity (salience), conditioned stimulus duration, or tastequality. Altering the validity of visual cues did not facilitateflavour avoidance nor did compounding the flavour cue with avisual cue. Although chicks showed increasing neophobia forincreasing concentrations of NaCl flavoured food, they did notlearn to avoid the food relative to controls (Experiment 1).Similarly, varying the amount of time allowed for ingestingthe NaCl flavoured food produced no differences between groups(Experiment 2). Since it was possible that NaCl might produceconsiderable malaise in its own right, the third experimentwas a partial replication of Experiment 2 using sucrose flavouredfood. Again, there was no effect due to conditioned stimulusduration. The final experiment showed, firstly, that the failureto develop flavour aversions cannot be attributed to overshadowingby familiar visual cues and, secondly, that aversions for NaClflavoured food cannot be potentiated by the presence of a noveland highly salient visual cue. These results suggest that previousfailures to demonstrate flavoured food aversions in chicks arenot due to procedural inadequacies but, rather, due to an organismicconstraint. Whether this constraint is associative, physiologicalor attentional remains to be determined.
The authors express appreciation to Marion Connors, Paula Halland Graeme Negri for technical assistance. 相似文献
479.
Serafino Pantano Valérie Dubost Katy Darribat Philippe Couttet Olivier Grenet Steven Busch Pierre Moulin 《Journal of molecular histology》2013,44(6):733-747
Dipeptidyl peptidase IV (DPP4) is a peptidase whose inhibition is beneficial in Type II diabetes treatment. Several evidences suggest potential implication of DPP4 in skin disorders such as psoriasis, keloids and fibrotic skin diseases where its inhibition could also be beneficial. DPP4 expression in human skin was described mainly in dermal fibroblasts and a subset of keratinocytes in the basal layer. Of importance in the perspective of preclinical experimentation, DPP4 distribution in skin of non-human primate species has not been documented. This report evidences unexpected differences between a set of human and cynomolgus monkey skin samples revealing a major expression of DPP4 in eccrine sweat glands of cynomolgus monkeys but not in humans. This represents a unique distinctive feature compared to the conserved expression of dipeptidyl peptidases 8 and 9 and potential relevant DPP4 substrates such as neuropeptide Y (NPY) and receptors (NPY-receptor 1 and Neurokinin receptor). Finally the observation that cathepsin D, an unrelated protease, shows the opposite expression compared to DPP4 (present in human but not in cynomolgus monkey eccrine sweat glands) could indicate that human eccrine sweat glands evolved a divergent protease repertoire compared to non-human primates. These unexpected differences in the eccrine sweat glands protease repertoire will need to be confirmed extending the analysis to a major number of donors but could imply possible biochemical divergences, reflecting the functional evolution of the glands and the control of their activity. Our findings also demonstrate that non-human primates studies aiming at understanding DPP4 function in skin biology are not readily translatable to human. 相似文献
480.
Biotechnology Letters - Functional characterization of metagenomic DNA often involves expressing heterologous DNA in genetically tractable microorganisms such as Escherichia coli. Functional... 相似文献