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Ontogenetic stages of ceratopsian dinosaur Psittacosaurus in bone histology

100%

Zhao Q., Benton M. J., Hayashi S., Xu X.

Acta Palaeontologica Polonica

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2019

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tom 64

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nr 2

The early ceratopsians Psittacosaurus and Protoceratops have provided important information on dinosaurian development because of abundant specimens of adults, subadults, juveniles, and even hatchlings. Here we present new data and methods for identifying key growth stages from bone histology. Previous studies on Psittacosaurus lujiatunensis from the Early Cretaceous Jehol Biota of China did not present in-depth analysis of growth patterns. Based on a histological study of 43 thin sections from 17 individuals of this species, we recognize four histological ontogenetic stages, i.e., hatchling, juvenile, sub-adult, and adult, but no fully-grown stage. We estimate life history and longevity from diaphyseal growth line counts and other features of histology. We show that P. lujiatunensis grew fast in early stages (hatchling, juvenile, and subadult), according to the density of vascular canals and the different type of bone tissue; the deposition of parallel fibred bone tissue in the outer cortex of the subadult stage indicates that growth rate was slowing down. We introduce a new graphical method to estimate the occurrence and volumes of vascular canals from thin sections more accurately than current two-dimensional approaches.

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Intraspecific genetic divergence of Paramecium bursaria and re-construction of the paramecian phylogenetic tree

100%

Hoshina R., Hayashi S., Imamura N.

Acta Protozoologica

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2006

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tom 45

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nr 4

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Function and evolution of ankylosaur dermal armor

88%

Hayashi S., Carpenter K., Scheyer T. M., Watabe M., Suzuki D.

Acta Palaeontologica Polonica

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2010

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tom 55

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nr 2

213-228

Ankylosaurs have spike−, plate−, and club−shaped osteoderms probably used as defensive and/or offensive weapons. Previous studies have proposed the evolution and function of small ankylosaur osteoderms, but histological variations in their defensive weapons are little known. Here, we provide comparisons of the internal structures in defensive weapons of ankylosaurs, which shed light on understanding their evolutionary history and function. Histological features of spikes, plates, and clubs are similar to those of small osteoderms in having thin compact bone, thick cancellous bone with large vascular canals, and abundant collagen fibers. A previous study demonstrated that each of the three groups of ankylosaurs (the Polacanthidae, Nodosauridae, and Ankylosauridae) have distinct arrangements of collagen fibers in small osteoderms. This study shows that spikes and clubs of ankylosaurs maintain the same characteristic features for each group despite the differences in shapes and sizes. These histological similarities suggest that various types of osteoderms in ankylosaurs retained the thin compact bone and abundant fiber structures of the small osteoderms during their evolution. Polacanthid spikes show thin compact bone, with less collagen fibers than in spikes of nodosaurids and spikes and clubs of ankylosaurids. Also, ankylosaurid plates with hollow bases are very thin in morphology and show thin compact bone. These results imply that the bone strengths of polacanthid spikes and ankylosaurid plates are lower than spikes and clubs of other ankylosaurs, indicating that they may be used more probably as display and/or thermoregulation rather than as weapons. It is thus probable that ankylosaur armor in general played more than just a defensive role.

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Muscarinic acetylcholine receptor subtype 4 is esssential for cholinergic stimulation of duodenal bicarbonate secretion in mice - relationship to D cell/somatostatin

88%

Takeuchi K., Kita K., Takahashi K., Aihara E., Hayashi S.

Journal of Physiology and Pharmacology

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2015

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tom 66

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nr 3

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Cinacalcet, a calcimimetic, prevents nonsteroidal antiinflammatory drug-induced small intestinal damage in rats

76%

Hayashi S., Kurata N., Kitahirachi E., Nishimura Y., Amagase K., Yano T., Takeuchi K.

Journal of Physiology and Pharmacology

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2013

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tom 64

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nr 4

6

An artery accompanying the sciatic nerve (arteria comitans nervi ischiadici) and the position of the hip joint: a comparative histological study using chick, mouse, and human foetal specimens

76%

Ishizawa A., Hayashi S., Nasu H., Abe H., Rodriguez-Vazquez J. F., Murakami G.

Folia Morphologica

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2013

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tom 72

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nr 1

Birds and reptiles always carry a long and thick artery accompanying the sciatic nerve (i.e. the sciatic artery) whereas mammals do not. We attempted to demonstrate a difference in courses of the nerve and the arteries of foetuses in relation to hip joint posture. Eight mid-term human foetuses (15–18 weeks), five mouse foetuses (E18), and five chick embryos (11 days after incubation) were examined histologically. Thin feeding arteries in the sciatic nerve were consistently observed in human foetuses in spite of the long, inferiorly curved course of the nerve around the ischium. The tissue around the human sciatic nerve was not so tight because of the medial and inferior shift of the nerve away from the hip joint. The foetal hip joint position differed among the species, being highly flexed in humans and almost at right angle flexion in mice and chicks. Because of deep adduction of the hip joint in the mouse, the knee was located near the midline of the body. The mouse sciatic nerve ran through the tight tissue along the head of the femur, whereas the chick nerve ran through the loose space even in the gluteal region. In birds, evolution of the pelvis including the hip joint without adduction seemed to make the arterial development possible. In mammals, highly flexed or adducted hip joint seemed to be one of the disturbing factors against development of the long and thick artery. A slight change in posture may cause significant arterial variation. (Folia Morphol 2013; 72, 1: 41–50)

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Interface between intramembranous and endochondral ossification in human foetuses

76%

Hayashi S., Kim J. H., Hwang S. E., Shibata S., Fujimiya M., Murakami G., Cho B. H.

Folia Morphologica

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2014

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tom 73

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nr 2

In the head and neck of human mid-term foetuses, the interface between areas of endochondral ossification and adjacent membranous (intramembranous) ossification is extensive. Using 8 foetal heads at 15–16 weeks, we have demonstrated differences in the matrices and composite cells between these 2 ossification processes, especially in the occipital squama and pterygoid process. Aggrecan-positive cartilage was shown to be invaded by a primitive bony matrix that was negative for aggrecan. At the interface, the periosteum was continuous with the perichondrium without any clear demarcation, but tenascin-c expression was restricted to the periosteum. In contrast, the interface between the epiphysis and shaft of the femur showed no clear localisation of tenascin-c. Versican expression tended to be restricted to the perichondrium. In the pterygoid process, the density of CD34-positive vessels was much higher in endochondral than in membranous ossification. The membranous part of the occipital was considered most likely to contribute to growth of the skull to accommodate the increased volume of the brain, while the membranous part of the pterygoid process seemed to be suitable for extreme flattening under pressure from the pterygoid muscles. (Folia Morphol 2014; 73, 2: 199–205)

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Low-dose exposure to di-(2-ethylhexyl) phthalate (DEHP) increases susceptibility to testicular autoimmunity in mice

64%

Hirai S., Naito M., Kuramasu M., Ogawa Y., Terayama H., Qu N., Hatayama N., Hayashi S., Itah M.

Reproductive Biology

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2015

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tom 15

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nr 3

9

Impairment by allyl isothiocyanate of gastric epithelial wound repair through inhibition of ion transporters

64%

Hayashi S., Nakamura E., Kubo Y., Takahashi N., Yamaguchi A., Matsui H., Hagen S. J., Takeuchi K.

Journal of Physiology and Pharmacology

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2008

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tom 59

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nr 4

691-706

Isothiocyanate is a transient receptor potential ankyrin 1 (TRPA1) agonist and also an inhibitor of ion transporters such as anion exchanger (AE) and Na+/HCO3- co-transporter (NBC). We examined the expression of TRPA1 and ion transporters in monolayers of the rat gastric epithelial cell line RGM1 and investigated the involvement of these factors in the inhibitory action of isothiocyanate on epithelial wound healing. After obtaining a confluent monolayer, a round artificial wound of constant size was induced in the center of the cell monolayer using a pencil-type mixer with a rotating silicon tip. Immediately after the wound induction, cells at the edge of the wound started to form lamellipodia, migrating towards the center of wound, and the cell-free area decreased with time. Addition of allyl isothiocyanate to standard buffer suppressed the recovery of the wound in a concentration-dependent manner without affecting the viability of the RGM1 cells. Icilin, another TRPA1 agonist, dose-dependently inhibited wound repair. Likewise, 4,4’-diisothio- cyanatostilbene-2,2’-disulfonic acid (DIDS), a stilbene compound containing an isothiocyanate group, also inhibited the recovery of epithelial wounds. In addition, the repair of epithelial wounds was suppressed when the cells were incubated in Na+, Cl- or HCO3- free buffer. The RGM1 cells expressed the mRNAs of AE2a and NBC1 but not TRPA1. These results suggested that isothiocyanate impairs the repair of epithelial wounds in RGM1 cells, probably through the inhibition of ion transporters such as AE2a and NBC1 and not the activation of the TRPA1 channel. It is assumed that the process of epithelial repair is associated with the regulation of cell volume and intracellular pH (pHi) by these ion transporters.

10

The profile of gene expression during bovine adipogenesis:cloning and expression of type XII collagen isoforms

52%

Aso H., Tahara K., Yamasaki T., Rose M. T., Kido T., Minashima T., Miyazawa K., Hayashi S., Sanosaka M., Watanabe K., Ohwada S., Yamaguchi T.

Journal of Animal and Feed Sciences. Supplement

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2004

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tom 13

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nr 1

Ograniczanie wyników

Ontogenetic stages of ceratopsian dinosaur Psittacosaurus in bone histology

Intraspecific genetic divergence of Paramecium bursaria and re-construction of the paramecian phylogenetic tree

Function and evolution of ankylosaur dermal armor

Muscarinic acetylcholine receptor subtype 4 is esssential for cholinergic stimulation of duodenal bicarbonate secretion in mice - relationship to D cell/somatostatin

Cinacalcet, a calcimimetic, prevents nonsteroidal antiinflammatory drug-induced small intestinal damage in rats

An artery accompanying the sciatic nerve (arteria comitans nervi ischiadici) and the position of the hip joint: a comparative histological study using chick, mouse, and human foetal specimens

Interface between intramembranous and endochondral ossification in human foetuses

Low-dose exposure to di-(2-ethylhexyl) phthalate (DEHP) increases susceptibility to testicular autoimmunity in mice

Impairment by allyl isothiocyanate of gastric epithelial wound repair through inhibition of ion transporters

The profile of gene expression during bovine adipogenesis:cloning and expression of type XII collagen isoforms