Post-mating morphological changes in the spermatozoon and spermatophore wall of the crayfish Astacus leptodactylus: Insight into a non-motile spermatozoon

Previous studies have demonstrated that colony forms of Blastocystis undergo cell death with numerous membrane-bound vesicles containing organelles located within the central vacuole, resembling morphological features of autophagy. In this study, we investigated whether Blastocystis underwent autophagy upon amino acid starvation and rapamycin treatment. Concurrently, we provide new insight into a possible function of the central vacuole. The use of the autophagy marker monodansylcadaverine, and the autophagy inhibitors3-methyladenine and wortmannin, showed the existence of autophagy in amino-acid-starved and rapamycin-treated Blastocystis. Confocal microscopy and transmission electron microscopy studies also showed morphological changes that were suggestive of autophagy. The unusually large size of the autophagic compartments within the parasite central vacuole was found to be unique in Blastocystis. In addition, autophagy was found to be triggered when cells were exposed to the cytotoxic antibody mAb 1D5, and autophagy was intensified in the presence of the caspase inhibitor zVAD.fmk. Taken together, our results suggest that the core machinery for autophagy is conserved in Blastocystis, and that it plays an important role in the starvation response and cell death of the parasite.

Download Full-text

Quantitative Analysis and Development of the Fore Feet of Arabian Foals from Birth to 1 Year of Age

Veterinary and Comparative Orthopaedics and Traumatology ◽

10.3415/vcot-16-11-0158 ◽

2017 ◽

Vol 30 (06) ◽

pp. 403-412 ◽

Cited By ~ 2

Author(s):

Babak Faramarzi ◽

Allison Salinger ◽

Andris Kaneps ◽

Yvette Nout-Lomas ◽

Holly Greene ◽

...

Keyword(s):

Limb Development ◽

Morphological Changes ◽

National Institutes Of Health ◽

First Year ◽

Joint Angles ◽

Digital Radiographs ◽

Radiographic Measurements ◽

Sesamoid Bones ◽

First Year Of Life ◽

Insight Into

Abstract Objectives The goal of this study was to quantify external and internal anatomical characteristics of the foal foot throughout the first year of age. Methods Digital radiographs and photographs were taken bimonthly of the forefeet of nine Arabian foals, beginning at about 2 weeks of age until 12 months of age. Sixty-eight linear and angular variables were measured using NIH (National Institutes of Health) Image J software. Statistical analyses were performed using piecewise random coefficient model and p-values < 0.05 were considered significant. Results Distinct changes in hoof development were identified between 4 and 8 months of age. Distinct changes were identified in severalexternal(conformational) measurements including hoof solar widths and lengths, palmar heel lengths, toe and heel angles and in several internal (radiographic) measurements including the widths and lengths of the phalanges and sesamoid bones as well as joint angles. Clinical Significance Existing knowledge of distal limb development in foals, particularly the foot, is limited. These findings define the measurable changes of the foal foot as it grows during the first year of life. These data provide an insight into the transformation of the hoof from its initial oval to a circular shape and from a club-like, cylindrical conformation to a more angled, conical conformation. This paper quantifies this development, ultimately allowing a better understanding of morphological changes in the foot of the growing foal.

Download Full-text

Periodontal disease and ‘oral health’ in the past: new insights from ancient Sudan on a very modern problem.

Dental Anthropology Journal ◽

10.26575/daj.v32i2.288 ◽

2019 ◽

Vol 32 (2) ◽

pp. 30-50 ◽

Cited By ~ 1

Author(s):

Rebecca Whiting ◽

Daniel Antoine ◽

Simon Hillson

Keyword(s):

Oral Health ◽

Periodontal Disease ◽

Morphological Changes ◽

Strong Support ◽

Neolithic Period ◽

Health Issues ◽

Archaeological Remains ◽

Modern Problem ◽

The Past ◽

Insight Into

As one of today’s major oral health issues, periodontal disease affects populations worldwide. Here, methods used to record its past prevalence are reviewed, including the problems associated with the use of measurements to record bone loss. Clinical and bioarchaeological research offers strong support for the Kerr method that records interdental septum morphological changes as a means of identifying gingivitis and periodontal disease. Using Kerr’s approach, four assemblages from Sudan dating to the Neolithic, Kerma and Medieval periods are examined to track the progression of the disease through time. Results show a significantly lower prevalence of periodontal disease and a limited distribution across the mouth in the Neolithic period. Significant differences were found between the sexes at the Medieval sites, which were not present at the Neolithic and Kerma sites. With no patient history and the cumulative effects of a dynamic and episodic disease - only a snapshot of which is captured at death - the concept of ‘oral health’ may be hard to apply in archaeological remains. As suggested by Kerr, it at best provides an insight into the periodontal status at death. Here, this ‘snapshot’ reveals differences across the mouth, over time and between sexes.

Download Full-text

Pineal Gland Morphology in Relation to Age and Season in Three Canidae Species

Journal of Morphological Sciences ◽

10.1055/s-0039-1698373 ◽

2019 ◽

Vol 36 (04) ◽

pp. 247-254

Author(s):

Svetlana Kalinina ◽

Viktor Ilyukha ◽

Lyudmila Uzenbaeva

Keyword(s):

Pineal Gland ◽

Morphological Changes ◽

Nyctereutes Procyonoides ◽

Raccoon Dog ◽

Silver Fox ◽

Reticular Fibers ◽

Different Ages ◽

Blue Fox ◽

Species Specific ◽

Insight Into

Abstract Introduction The aim of the present study was to determine the morphological features of the pineal gland in three closely related Canidae species (raccoon dog, Nyctereutes procyonoides Gray, 1834; silver fox, Vulpes vulpes L., 1758; and blue fox, Vulpes lagopus L., 1758) of different ages during the breeding (spring) and nonbreeding (winter) periods. Materials and Methods Histological analysis of the pineal glands of canids was performed. Results The morphological changes in the pineal gland detected in the current study are either age-associated, including increase in the reticular fibers and vascularization in the studied species, as well as increase in the amount of the protruding septae in the blue fox, or seasonally related, including an increase in the number and size of blood vessels. The present work reported two types of pigments: lipofuscin (primarily in the silver fox) and melanin (primarily in the raccoon dog and in the blue fox). The pineal gland in the blue fox is characterized by the ability to form corpora arenacea. Conclusions The present study provides the first insight into the morphological changes of the pineal gland in three closely related Canidae species of different ages during the breeding (spring) and nonbreeding (winter) periods, and showed some species-specific features of gland morphology. The aspects concerning the biogenesis of the calcium concretions and the factors influencing the accumulation of pigments need further investigation.

Download Full-text

Fire Phenomena of Rigid Polyurethane Foams

Polymers ◽

10.3390/polym10101166 ◽

2018 ◽

Vol 10 (10) ◽

pp. 1166 ◽

Cited By ~ 15

Author(s):

Martin Günther ◽

Alessandra Lorenzetti ◽

Bernhard Schartel

Keyword(s):

Cross Sections ◽

Cone Calorimeter ◽

Morphological Changes ◽

Methodological Approach ◽

Thermal Inertia ◽

Polyurethane Foams ◽

Fire Behaviour ◽

Limiting Oxygen Index ◽

Rigid Polyurethane Foams ◽

Insight Into

Rigid polyurethane foams (RPUFs) typically exhibit low thermal inertia, resulting in short ignition times and rapid flame spread. In this study, the fire phenomena of RPUFs were investigated using a multi-methodological approach to gain detailed insight into the fire behaviour of pentane- and water-blown polyurethane (PUR) as well as pentane-blown polyisocyanurate polyurethane (PIR) foams with densities ranging from 30 to 100 kg/m3. Thermophysical properties were studied using thermogravimetry (TG); flammability and fire behaviour were investigated by means of the limiting oxygen index (LOI) and a cone calorimeter. Temperature development in burning cone calorimeter specimens was monitored with thermocouples inside the foam samples and visual investigation of quenched specimens’ cross sections gave insight into the morphological changes during burning. A comprehensive investigation is presented, illuminating the processes taking place during foam combustion. Cone calorimeter tests revealed that in-depth absorption of radiation is a significant factor in estimating the time to ignition. Cross sections examined with an electron scanning microscope (SEM) revealed a pyrolysis front with an intact foam structure underneath, and temperature measurement inside burning specimens indicated that, as foam density increased, their burning behaviour shifted towards that of solid materials. The superior fire performance of PIR foams was found to be based on the cellular structure, which is retained in the residue to some extent.

Download Full-text

Elastic Properties of Porous Structural Ceramics Produced by Plasma-Spraying

MRS Proceedings ◽

10.1557/proc-521-45 ◽

1998 ◽

Vol 521 ◽

Cited By ~ 1

Author(s):

A. Wanner

Keyword(s):

Plasma Spraying ◽

Morphological Changes ◽

Mass Density ◽

Ceramic Materials ◽

Elastic Stiffness ◽

Model Material ◽

Structural Ceramics ◽

Deep Insight ◽

The Relationship ◽

Insight Into

ABSTRACTThis study focuses on the relationship between porosity and elastic stiffness of structural ceramic materials produced by plasma-spraying. Mg-AI-spinel was chosen as a model material and studied in as-sprayed condition as well as upon annealing to increasingly higher temperatures up to 1650°C. The detailed analysis of the stiffness and mass density evolution offers a deep insight into the initial microstructural state of the material and into the morphological changes that occur upon heat treatment.

Download Full-text

BMP controls dorsoventral and neural patterning in indirect-developing hemichordates providing insight into a possible origin of chordates

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1901919116 ◽

2019 ◽

Vol 116 (26) ◽

pp. 12925-12932 ◽

Cited By ~ 2

Author(s):

Yi-Hsien Su ◽

Yi-Chih Chen ◽

Hsiu-Chi Ting ◽

Tzu-Pei Fan ◽

Ching-Yi Lin ◽

...

Keyword(s):

Nervous System ◽

Morphological Changes ◽

Sister Group ◽

Neural Plate ◽

Bmp Signaling ◽

Neural Patterning ◽

Mechanistic Basis ◽

Lateral Organization ◽

Insight Into ◽

Origin Of Chordates

A defining feature of chordates is the unique presence of a dorsal hollow neural tube that forms by internalization of the ectodermal neural plate specified via inhibition of BMP signaling during gastrulation. While BMP controls dorsoventral (DV) patterning across diverse bilaterians, the BMP-active side is ventral in chordates and dorsal in many other bilaterians. How this phylum-specific DV inversion occurs and whether it is coupled to the emergence of the dorsal neural plate are unknown. Here we explore these questions by investigating an indirect-developing enteropneust from the hemichordate phylum, which together with echinoderms form a sister group of the chordates. We found that in the hemichordate larva, BMP signaling is required for DV patterning and is sufficient to repress neurogenesis. We also found that transient overactivation of BMP signaling during gastrulation concomitantly blocked mouth formation and centralized the nervous system to the ventral ectoderm in both hemichordate and sea urchin larvae. Moreover, this mouthless, neurogenic ventral ectoderm displayed a medial-to-lateral organization similar to that of the chordate neural plate. Thus, indirect-developing deuterostomes use BMP signaling in DV and neural patterning, and an elevated BMP level during gastrulation drives pronounced morphological changes reminiscent of a DV inversion. These findings provide a mechanistic basis to support the hypothesis that an inverse chordate body plan emerged from an indirect-developing ancestor by tinkering with BMP signaling.

Download Full-text

Ionophore-resistant mutant of Toxoplasma gondii reveals involvement of a sodium/hydrogen exchanger in calcium regulation

The Journal of Cell Biology ◽

10.1083/jcb.200309097 ◽

2004 ◽

Vol 165 (5) ◽

pp. 653-662 ◽

Cited By ~ 52

Author(s):

Gustavo Arrizabalaga ◽

Felix Ruiz ◽

Silvia Moreno ◽

John C. Boothroyd

Keyword(s):

Toxoplasma Gondii ◽

Morphological Changes ◽

Resistant Mutant ◽

Host Cells ◽

Ionophore A23187 ◽

Obligate Intracellular ◽

Sodium Hydrogen ◽

Sodium Hydrogen Exchanger ◽

Direct Genetic Evidence ◽

Insight Into

Calcium is a critical mediator of many intracellular processes in eukaryotic cells. In the obligate intracellular parasite Toxoplasma gondii, for example, a rise in [Ca2+] is associated with significant morphological changes and rapid egress from host cells. To understand the mechanisms behind such dramatic effects, we isolated a mutant that is altered in its responses to the Ca2+ ionophore A23187 and found the affected gene encodes a homologue of Na+/H+ exchangers (NHEs) located on the parasite's plasma membrane. We show that in the absence of TgNHE1, Toxoplasma is resistant to ionophore-induced egress and extracellular death and amiloride-induced proton efflux inhibition. In addition, the mutant has increased levels of intracellular Ca2+, which explains its decreased sensitivity to A23187. These results provide direct genetic evidence of a role for NHE1 in Ca2+ homeostasis and important insight into how this ubiquitous pathogen senses and responds to changes in its environment.

Download Full-text