Red muscle function in stiff-bodied swimmers: there and almost back again

Fishes with internalized and endothermic red muscles (i.e. tunas and lamnid sharks) are known for a stiff-bodied form of undulatory swimming, based on unique muscle–tendon architecture that limits lateral undulation to the tail region even though the red muscle is shifted anteriorly. A strong convergence between lamnid sharks and tunas in these features suggests that thunniform swimming might be evolutionarily tied to this specialization of red muscle, but recent observations on the common thresher shark ( Alopias vulpinus ) do not support this view. Here, we review the fundamental features of the locomotor systems in lamnids and tunas, and present data on in vivo muscle function and swimming mechanics in thresher sharks. These results suggest that the presence of endothermic and internalized red muscles alone in a fish does not predict or constrain the swimming mode to be thunniform and, indeed, that the benefits of this type of muscle may vary greatly as a consequence of body size.

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Fish swimming: patterns in muscle function

Journal of Experimental Biology ◽

10.1242/jeb.202.23.3397 ◽

1999 ◽

Vol 202 (23) ◽

pp. 3397-3403 ◽

Cited By ~ 26

Author(s):

J.D. Altringham ◽

D.J. Ellerby

Keyword(s):

Muscle Function ◽

Muscle Activation ◽

Muscle Power ◽

Lateral Displacement ◽

Travelling Wave ◽

The Body ◽

Caudal Fin ◽

Swimming Mode ◽

Undulatory Swimming

Undulatory swimming in fish is powered by the segmental body musculature of the myotomes. Power generated by this muscle and the interactions between the fish and the water generate a backward-travelling wave of lateral displacement of the body and caudal fin. The body and tail push against the water, generating forward thrust. The muscle activation and strain patterns that underlie body bending and thrust generation have been described for a number of species and show considerable variation. This suggests that muscle function may also vary among species. This variation must be due in large part to the complex interactions between muscle mechanical properties, fish body form, swimming mode, swimming speed and phylogenetic relationships. Recent work in several laboratories has been directed at studying patterns of muscle power output in vitro under simulated swimming conditions. This work suggests that the way that fish generate muscle power and convert it into thrust through the body and caudal fin does indeed vary. However, despite the differences, several features appear to be common to virtually all species studied and suggest where future effort should be directed if muscle function in swimming fish is to be better understood.

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How to build a pectoral fin: functional morphology and steady swimming kinematics of the spotted ratfish (Hydrolagus colliei)

Canadian Journal of Zoology ◽

10.1139/z10-043 ◽

2010 ◽

Vol 88 (8) ◽

pp. 774-780 ◽

Cited By ~ 3

Author(s):

K. L. Foster ◽

T. E. Higham

Keyword(s):

Body Size ◽

Adductor Muscle ◽

Squalus Acanthias ◽

Pectoral Fin ◽

Phylogenetic Placement ◽

Swimming Mode ◽

Fine Control ◽

Swimming Kinematics ◽

Stroke Amplitude

Aquatic flight is the primary locomotor mode for many animals, including penguins and other diving birds, turtles, and fishes, where labriform and rajiform swimming have been the focus of much interest. However, despite its interesting phylogenetic placement, little is known about the aquatic flight of the sister lineage to the elasmobranchs, the chimaerids. This study investigates the pectoral fin morphology of the spotted ratfish ( Hydrolagus colliei (Lay and Bennett, 1839)) as a possible factor underlying the kinematics of their steady swimming by comparing muscle mass, distribution, and abductor to adductor ratio with those of a closely related shark ( Squalus acanthias L., 1758). Despite fundamental differences in swimming mode, abductor to adductor muscle ratio did not differ between species (P = 0.49). However, the muscle ratio in the spotted ratfish was similar to the range determined in other flapping labriform swimmers. Ratfish had larger, distally placed pectoral fin muscles relative to body size than dogfish (P < 0.0001) possibly aiding in fine control. Stroke amplitude remained constant across body size (P = 0.26) and relative swimming speed (P = 0.23) in the ratfish, whereas the downstroke was significantly faster than the upstroke (P = 0.006). The similar muscle ratio, despite differences in stroke phases, may be explained by physiological or in vivo recruitment differences between abductors and adductors in the ratfish.

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The Application of the Cold Atmospheric Plasma-Activated Solutions in Cancer Treatment

Anti-Cancer Agents in Medicinal Chemistry ◽

10.2174/1871520617666170731115233 ◽

2018 ◽

Vol 18 (6) ◽

pp. 769-775 ◽

Cited By ~ 13

Author(s):

Dayun Yan ◽

Jonathan H. Sherman ◽

Michael Keidar

Keyword(s):

Cancer Treatment ◽

Atmospheric Plasma ◽

Current Status ◽

Cold Atmospheric Plasma ◽

Anti Cancer ◽

Long Time ◽

Key Topics ◽

The Common

Background: Over the past five years, the cold atmospheric plasma-activated solutions (PAS) have shown their promissing application in cancer treatment. Similar as the common direct cold plasma treatment, PAS shows a selective anti-cancer capacity in vitro and in vivo. However, different from the direct cold atmospheric plasma (CAP) treatment, PAS can be stored for a long time and can be used without dependence on a CAP device. The research on PAS is gradually becoming a hot topic in plasma medicine. Objectives: In this review, we gave a concise but comprehensive summary on key topics about PAS including the development, current status, as well as the main conclusions about the anti-cancer mechanism achieved in past years. The approaches to make strong and stable PAS are also summarized.

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Allometry and Paleoecology of Medial Miocene Dwarf Rhinoceroses from the Texas Gulf Coastal Plain

Paleobiology ◽

10.1017/s0094837300004322 ◽

1982 ◽

Vol 8 (1) ◽

pp. 16-30 ◽

Cited By ~ 53

Author(s):

Donald R. Prothero ◽

Paul C. Sereno

Keyword(s):

Body Size ◽

Coastal Plain ◽

Sympatric Species ◽

High Plains ◽

Gulf Coastal Plain ◽

Canine Tooth ◽

Positive Allometry ◽

Mammalian Faunas ◽

The Common ◽

Limb Proportions

Barstovian (medial Miocene) mammalian faunas from the Texas Gulf Coastal Plain contained four apparently sympatric species of rhinoceroses: the common forms Aphelops megalodus and Teleoceras medicornutus, a dwarf Teleoceras, and a dwarf Peraceras. Previous work has suggested positive allometry in tooth area with respect to body size in several groups of mammals, i.e., larger mammals have relatively more tooth area. However, dwarfing lineages were shown to have relatively more tooth area for their body size. Our data show no significant allometry in post-canine tooth area of either artiodactyls or ceratomorphs. Similarly, dwarf rhinoceroses and hippopotami show no more tooth area than would be predicted for their size. Limbs are proportionately longer and more robust in larger living ceratomorphs (rhinos and tapirs) than predicted by previous authors. Limb proportions of both dwarf rhinoceroses and dwarf hippopotami are even more robust than in their living relatives.The high rhinoceros diversity reflects the overall high diversity of Barstovian faunas from the Texas Gulf Coastal Plain. The first appearance of several High Plains mammals in these faunas indicates “ecotone”-like conditions as faunal composition changed. Study of living continental dwarfs shows that there is commonly an ecological separation between browsing forest dwarfs and their larger forebears, which are frequently savannah grazers. This suggests that the dwarf rhinoceroses might have been forest browsers which were sympatric with the larger grazing rhinos of the High Plains during the Barstovian invasion. The continental dwarf model also suggests that insular dwarfism may be explained by the browsing food resources that predominate on islands.

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Stu2p binds tubulin and undergoes an open-to-closed conformational change

The Journal of Cell Biology ◽

10.1083/jcb.200511010 ◽

2006 ◽

Vol 172 (7) ◽

pp. 1009-1022 ◽

Cited By ~ 87

Author(s):

Jawdat Al-Bassam ◽

Mark van Breugel ◽

Stephen C. Harrison ◽

Anthony Hyman

Keyword(s):

Conformational Change ◽

Conformational Transition ◽

Budding Yeast ◽

Microtubule Dynamics ◽

Open Structure ◽

Microtubule Associated Proteins ◽

Associated Proteins ◽

The Common

Stu2p from budding yeast belongs to the conserved Dis1/XMAP215 family of microtubule-associated proteins (MAPs). The common feature of proteins in this family is the presence of HEAT repeat–containing TOG domains near the NH2 terminus. We have investigated the functions of the two TOG domains of Stu2p in vivo and in vitro. Our data suggest that Stu2p regulates microtubule dynamics through two separate activities. First, Stu2p binds to a single free tubulin heterodimer through its first TOG domain. A large conformational transition in homodimeric Stu2p from an open structure to a closed one accompanies the capture of a single free tubulin heterodimer. Second, Stu2p has the capacity to associate directly with microtubule ends, at least in part, through its second TOG domain. These two properties lead to the stabilization of microtubules in vivo, perhaps by the loading of tubulin dimers at microtubule ends. We suggest that this mechanism of microtubule regulation is a conserved feature of the Dis1/XMAP215 family of MAPs.

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The common antitussive agent dextromethorphan protects against hyperoxia-induced cell death in established in vivo and in vitro models of neonatal brain injury

Neuroscience ◽

10.1016/j.neuroscience.2014.05.059 ◽

2014 ◽

Vol 274 ◽

pp. 260-272 ◽

Cited By ~ 4

Author(s):

A. Posod ◽

K. Pinzer ◽

M. Urbanek ◽

K. Wegleiter ◽

M. Keller ◽

...

Keyword(s):

Cell Death ◽

Brain Injury ◽

In Vitro Models ◽

Neonatal Brain ◽

Neonatal Brain Injury ◽

The Common

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A Wolf in Another Wolf’s Clothing: Post-Genomic Regulation Dictates Venom Profiles of Medically-Important Cryptic Kraits in India

Toxins ◽

10.3390/toxins13010069 ◽

2021 ◽

Vol 13 (1) ◽

pp. 69 ◽

Cited By ~ 1

Author(s):

Kartik Sunagar ◽

Suyog Khochare ◽

R. R. Senji Laxme ◽

Saurabh Attarde ◽

Paulomi Dam ◽

...

Keyword(s):

Negative Impact ◽

Indian Subcontinent ◽

Clinical Effectiveness ◽

Venom Gland ◽

Western India ◽

The Common ◽

Genomic Regulation

The Common Krait (Bungarus caeruleus) shares a distribution range with many other ‘phenotypically-similar’ kraits across the Indian subcontinent. Despite several reports of fatal envenomings by other Bungarus species, commercial Indian antivenoms are only manufactured against B. caeruleus. It is, therefore, imperative to understand the distribution of genetically distinct lineages of kraits, the compositional differences in their venoms, and the consequent impact of venom variation on the (pre)clinical effectiveness of antivenom therapy. To address this knowledge gap, we conducted phylogenetic and comparative venomics investigations of kraits in Southern and Western India. Phylogenetic reconstructions using mitochondrial markers revealed a new species of krait, Romulus’ krait (Bungarus romulusi sp. nov.), in Southern India. Additionally, we found that kraits with 17 mid-body dorsal scale rows in Western India do not represent a subspecies of the Sind Krait (B. sindanus walli) as previously believed, but are genetically very similar to B. sindanus in Pakistan. Furthermore, venom proteomics and comparative transcriptomics revealed completely contrasting venom profiles. While the venom gland transcriptomes of all three species were highly similar, venom proteomes and toxicity profiles differed significantly, suggesting the prominent role of post-genomic regulatory mechanisms in shaping the venoms of these cryptic kraits. In vitro venom recognition and in vivo neutralisation experiments revealed a strong negative impact of venom variability on the preclinical performance of commercial antivenoms. While the venom of B. caeruleus was neutralised as per the manufacturer’s claim, performance against the venoms of B. sindanus and B. romulusi was poor, highlighting the need for regionally-effective antivenoms in India.

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