Bowhead whales are some of the largest animals that occupy the Arctic Circle. Despite the challenges of living and giving birth in icy waters, having huge blubber stores, eating a fat-rich diet, and undergoing arduous migrations, bowheads achieved…
Swallowing in mammals requires the precise coordination of multiple oropharyngeal structures, including the palatopharyngeal arch. During a typical swallow, the activity of the palatopharyngeus muscle produces pharyngeal shortening to assist in…
In the late 1980s, annual carbon isotope cycles in the baleen plates of bowhead whales formed the basis of the first effective means of estimating bowhead age. However, the baleen aging method could only be used for aging subadult whales less than…
Bering–Chukchi–Beaufort Sea bowhead whales are born at about 4.2m in length and 1000kg, in lead systems along the NW Alaskan coast. Bowheads in the other northern stocks are also born in ice-covered seas. Maximum body lengths (standard measure) can…
The skull of the bowhead whale is composed of all the bones commonly found in mammals, although the shape of these bones is far from ordinary. Features related to feeding dominate the skull: there are no teeth, and the rostrum is long and curved,…
An understanding of the functional morphology of the bowhead whale continues to have significance for population management. This chapter first examines the anatomical features of the bowhead whale reproductive system, with an emphasis on the female.…
The commercial hunt of the four stocks of bowhead whales by the nations of Europe and North America commenced in 1540 and came to an effective end at the start of World War I. At that time, all four stocks had been driven to near extinction. Whalers…
We discuss the evolution, phylogenetic relations to right whales, and geographical distribution of bowhead whales. We summarize its relations to humans, including whaling by indigenous and European whalers, conservation efforts, and modern challenges…
The sensory biology of bowhead whales reflects features both related to their origin from land mammals and adaptations to their current environment, polar seas. There is anatomical and genomic evidence that bowheads have a sense of smell. Their sense…
The prenatal development of bowhead whales is poorly known, and no complete ontogenetic series exist. However, the available embryos and fetuses elucidate aspects of the development of the species, as well as that of all of mysticetes in general, and…
The postcranial skeleton of bowhead whales was described in detail more than 100 years ago. The musculature of bowheads has not been studied in detail but matches that of other mysticetes in general features. In this chapter, we focus on some aspects…
The order Cetacea (dolphins, whales, and porpoises) evolved from terrestrial artiodactyls (even‐toed ungulates) around 50 million years ago. This transition from land to water occurred over an evolutionarily short period of less than 10 million years…
Chronic inflammation in aging is characterized by increased inflammatory cytokines, bone loss, decreased adaptation, and defective tissue repair in response to injury. Aging leads to inherent changes in mesenchymal stem cell (MSC) differentiation,…
We have previously identified osteoactivin (OA), encoded by Gpnmb, as an osteogenic factor that stimulates osteoblast differentiation in vitro. To elucidate the importance of OA in osteogenesis, we characterized the skeletal phenotype of a mouse…
We previously reported on the importance of osteoactivin (OA/Gpnmb) in osteogenesis. In this study, we examined the role of OA in osteoclastogenesis, using mice with a nonsense mutation in the Gpnmb gene (D2J) and wild-type controls (D2J/Gpnmb(+)).…
Infant birth weight affects neuromotor and biomechanical swallowing performance in infant pig models. Preterm infants are generally born low birth weight and suffer from delayed development and neuromotor deficits. These deficits include critical …
Joint inflammation is a key player in the pathogenesis of osteoarthritis (OA). Imperatorin, a plant-derived small molecule has been reported to have anti-inflammatory properties; however, its effect on chondrocytes is not known. Here, we investigated…
Accumulating evidence suggests that inflammation has a key role in the pathogenesis of osteoarthritis (OA). Nitric oxide (NO) has been established as one of the major inflammatory mediators in OA and drives many pathological changes during the…
OBJECTIVE: Osteoarthritis (OA) is characterized by cartilage degradation in the affected joints. Pomegranate fruit extract (PFE) inhibits cartilage degradation in vitro. The aim of this study was to determine whether oral consumption of PFE inhibits…
OBJECTIVE: Hedgehog (HH) signaling has recently been associated with cartilage degradation in osteoarthritis (OA). Because interleukin-1beta (IL-1beta) has been implicated as a principal instigator of OA, we sought to determine whether
Bats are the only mammals to have achieved powered flight. A key innovation allowing for bats to conquer the skies was a forelimb modified into a flexible wing. The wing bones of bats are exceptionally long and dynamically bend with wingbeats. Bone …
OBJECTIVE: Mitochondrial dysfunction, oxidative stress and chondrocyte death are important contributors to the development and pathogenesis of osteoarthritis (OA). In this study, we determined the expression and role of Parkin in the clearance of…
Mitochondrial function is impaired in osteoarthritis (OA) but its impact on cartilage catabolism is not fully understood. Here, we investigated the molecular mechanism of mitochondrial dysfunction-induced activation of catabolic response in …
OBJECTIVE: Lysosomes are the major catabolic organelle of the cell and regulate the macromolecular and organelle turnover and programmed cell death. Here, we investigated the lysosome dysfunction in cartilage and its role in chondrocytes apoptosis…
BACKGROUND/AIMS: Butein (2',3,4,4'-Tetrahydroxychalcone), a polyphenol produced by several plants including Butea monoserpma, has been reported to exert potent anti-inflammatory activity but the mechanism remains unknown. In the present work we…
OBJECTIVE: Cytokine expression is tightly regulated post-transcriptionally but high levels of IL-6 in osteoarthritis (OA) indicate disruption of regulatory mechanisms. ZCCHC6 enzyme is implicated in post-transcriptional regulation of inflammatory…
Objective: Cytokine expression is tightly regulated posttranscriptionally, but high levels of interleukin‐6 (IL‐6) in patients with osteoarthritis (OA) indicate that regulatory mechanisms are disrupted in this disorder. The enzyme ZCCHC6 (zinc‐finger…
BACKGROUND/OBJECTIVE: Osteoarthritis (OA) is a leading cause of joint dysfunction, disability and poor quality of life in the affected population. The underlying mechanism of joint dysfunction involves increased oxidative stress, inflammation, high…
Peste-des-petits-ruminants is a highly contagious and fatal disease of goats and sheep caused by non-segmented, negative strand RNA virus belonging to the Morbillivirus genus-Peste-des-petits-ruminants virus (PPRV) which is evolutionarily closely…
Osteoarthritis (OA) is the most prevalent joint degenerative disease leading to irreversible structural and functional changes in the joint and is a major cause of disability and reduced life expectancy in ageing population. Despite the high …