Leptin in Whales: Validation and Measurement of mRNA Expression by Absolute Quantitative Real-Time PCR
obesity; mammals; Science & Technology - Other Topics; resistance; mass; weight; quantification; housekeeping genes; reference genes; rt-pcr; serum leptin
Leptin is the primary hormone in mammals that regulates adipose stores. Arctic adapted cetaceans maintain enormous adipose depots, suggesting possible modifications of leptin or receptor function. Determining expression of these genes is the first step to understanding the extreme physiology of these animals, and the uniqueness of these animals presents special challenges in estimating and comparing expression levels of mRNA transcripts. Here, we compare expression of two model genes, leptin and leptin-receptor gene-related product (OB-RGRP), using two quantitative real-time PCR (qPCR) methods: "relative'' and "absolute''. To assess the expression of leptin and OB-RGRP in cetacean tissues, we first examined how relative expression of those genes might differ when normalized to four common endogenous control genes. We performed relative expression qPCR assays measuring the amplification of these two model target genes relative to amplification of 18S ribosomal RNA (18S), ubiquitously expressed transcript (Uxt), ribosomal protein 9 (Rs9) and ribosomal protein 15 (Rs15) endogenous controls. Results demonstrated significant differences in the expression of both genes when different control genes were employed; emphasizing a limitation of relative qPCR assays, especially in studies where differences in physiology and/or a lack of knowledge regarding levels and patterns of expression of common control genes may possibly affect data interpretation. To validate the absolute quantitative qPCR methods, we evaluated the effects of plasmid structure, the purity of the plasmid standard preparation and the influence of type of qPCR "background'' material on qPCR amplification efficiencies and copy number determination of both model genes, in multiple tissues from one male bowhead whale. Results indicate that linear plasmids are more reliable than circular plasmid standards, no significant differences in copy number estimation based upon background material used, and that the use of ethanol precipitated, linearized plasmid preparation produce the most reliable results.
Ball H C; Holmes R K; Londraville R L; Thewissen J G M; Duff R J
PLOS ONE
2013
2013-01
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1371/journal.pone.0054277" target="_blank" rel="noreferrer noopener">10.1371/journal.pone.0054277</a>
Morphological Correlates Of Substrate Use In Didelphid Marsupials: Implications For Primate Origins
behavior; cercopithecidae; cheirogaleid primates; didelphid marsupials; evolution; foot; forest; french-guyana; hand; locomotion; mass; opossum caluromys-philander; posture; prehensility; small mammals; Zoology
The ability of some mammals to forage on vines or terminal branches depends upon their grasping extremities. This study tests the functional link between use of small-diameter supports and grasping abilities by comparing hand and foot proportions in didelphid marsupials. Metapodials and phalanges were measured for the hands and feet of six didelphid taxa characterized by different patterns of substrate use. Comparisons of hand and foot proportions demonstrate that Marmosa and Caluromys, didelphids that rely on vines or terminal branches, possess more prehensile extremities than Monodelphis, Didelphis, and Philander, which travel and feed mainly on the ground. Moreover, the proportions of the hand and foot of Marmosa and Caluromys are more similar to those of cheirogaelid primates than those of other didelphids. These morphological data corroborate the suggestion that the use of branches of small diameter was an important factor in the development of prehensile hands and feet in early primates.
Lemelin P
Journal of Zoology
1999
1999-02
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1017/s0952836999002046" target="_blank" rel="noreferrer noopener">10.1017/s0952836999002046</a>
Obesity And Breast Cancer Prognosis: An Expanding Body Of Evidence
mass; Oncology; receiving adjuvant chemotherapy; risk; size; stage; weight; women
Dignam J J; Mamounas E P
Annals of Oncology
2004
2004-06
Journal Article or Conference Abstract Publication
<a href="http://doi.org/10.1093/annonc/mdh241" target="_blank" rel="noreferrer noopener">10.1093/annonc/mdh241</a>
PARAVERTEBRALMASSES IN BLUE-TAILED MONITOR, VARANUS DORIANUS, INDICATIVE OF SOFT-TISSUE INFECTION WITH ASSOCIATED OSTEOMYELITIS
bone; Bone disease; cells; classification; deformans pagets-disease; lizard; mass; of-rheumatology criteria; osteoarthritis; osteomyelitis; Paget's disease; spondyloarthropathy; Varanus dorianus; vertebrae; Veterinary Sciences; virus
Paravertebral osseous masses in reptiles have been attributed to Paget's disease on the basis of histology. Histologically recognized mosaic architecture and cement lines, however, lack specificity. A Varanus dorianus with this condition was subjected to standard and computerized tomography. Because the masses were extraskeletal in nature, Paget's disease could be excluded. Although interpretation of the computed tomography suggested the process to be entirely extraskeletal, standard radiographs revealed disorganized vertebral architecture characteristic of osteomyelitis, crossing intervertebral spaces. Posttraumatic myositis ossificans and calcified hematoma were confidently excluded as diagnoses. The etiology of paraspinal masses in this V. dorianus appears attributable to infection, with infection of a puncture wound hypothesized as the underlying process. If one extrapolates the findings in this one animal, it seems reasonable to suggest that consideration be given to investigating the possibility of an infectious origin when similar masses are recognized in other reptiles.
Rothschild B M
Journal of Zoo and Wildlife Medicine
2014
2014-03
Journal Article
<a href="http://doi.org/10.1638/2012-0295r.1" target="_blank" rel="noreferrer noopener">10.1638/2012-0295r.1</a>