scholarly journals Structure of the yolk syncytial layer during postembryonic development of Andinoacara rivulatus (Günther), 1860 (Cichlidae)

2019 ◽  
Vol 323 (4) ◽  
pp. 523-532
Author(s):  
E.A. Kondakova ◽  
F.N. Shkil ◽  
V.I. Efremov
Keyword(s):  
Morphological Diversity ◽  
Postembryonic Development ◽  
Early Ontogeny ◽  
Pigment Cells ◽  
Apical Surface ◽  
Immune Functions ◽  
Yolk Syncytial Layer ◽  
Bony Fishes ◽  
Well Differentiated ◽  
Species Specific

Temporary “extraembryonic” systems are important for the development of representatives of many Metazoan taxa and are characterized by significant diversity. The yolk syncytial layer (YSL), a component of embryonic and larval teleost yolk complex, is a provisory structure performing morphogenetic, nutritional and immune functions. Despite the crucial role of YSL in the early ontogeny of bony fishes, the data concerning YSL structure and morphological diversity is scant. Here, we describe YSL organization in the postembryonic development of the green terror cichlid, Andinoacara rivulatus, studied by the analysis of serial histological sections. YSL cytoplasm contains numerous yolk inclusions decreasing in size from basal to apical surface of YSL. The mode of yolk engulfment is one of the most variable YSL characteristics in the species studied. The yolk syncytial nuclei (YSN) have especially complex shape, and large nucleoli are well distinguished. The yolk mass consists of homogenous globules. It contains the oil globules, many of which are in contact with the basal surface of YSL. The YSL thickness is very uneven due to its interaction with oil globules. Significant part of the apical YSL surface is associated with the blood vessels and pigment cells. During the period of mixed feeding the yolk complex locates anterior to the liver. Thus, the yolk complex of green terror cichlid has a well-differentiated structure. Our results contribute to the knowledge of the morphology of fish temporary systems and allow clarifying their common and species-specific features.

FEATURES OF FORMATION OF THE MAIN SYSTEMS AND ORGANS IN EARLY LARVAE OF MULLETS (LIZA AURATA, RISSO, 1810)

2017 ◽  
pp. 98-106
Author(s):  
Dariya Aleksandrovna Gavrilova ◽  
Maria Pavlovna Grushko
Keyword(s):  
Nervous System ◽  
Sample Selection ◽  
Early Ontogeny ◽  
Basal Cells ◽  
The Caspian Sea ◽  
Liza Aurata ◽  
Morphological Organization ◽  
Organ Systems ◽  
Major Organ ◽  
Well Differentiated

The aim of this work was to study peculiarities of mullet morphological organization during early ontogeny. Sample selection was made on board Caspian research and development Institute of Fisheries’ research vessel in period from June to September, 2015 in Russian waters of the Caspian Sea. Larvae aged 10 days could be characterized by heterochrony in the development of major organ systems. Nervous system and sense organs were well developed. The eyeball had all membranes well-differentiated, in the retina all the layers were formed. The olfactory fossae had cells of 3 types: olfactory receptor cells, supporting cells and basal cells. There was observed intensive formation of respiratory, cardiovascular, excretory and digestive systems. The early development of the nervous system and sensory organs of the larvae indicated adaptation of mullet to active life.

An approach to the understanding of the clinical-etiopathological aspect of COVID-19 (SARS-CoV-2)

2020 ◽  
Vol 11 (SPL1) ◽  
pp. 862-869
Author(s):  
Meena Kumari ◽  
Monika Agrawal ◽  
Rakesh Kumar Singh ◽  
Parameswarappa S Byadgi
Keyword(s):  
World Health ◽  
Apical Surface ◽  
Therapy Assessment ◽  
Differentiated Cells ◽  
The World ◽  
Polarized Epithelia ◽  
Well Differentiated ◽  
Novel Coronavirus ◽  
Health Organization ◽  
Epidemiological Characteristics

Currently, the world is facing a health and socioeconomic crisis caused by the novel coronavirus disease COVID-19. On 11 March 2020, the World Health Organization (WHO) has declared this disease as a pandemic. The condition (COVID-19) is an infectious disorder triggered by a newly discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2. Most of the COVID-19 infected patients will experience mild to moderate respiratory symptoms and recover without any unique therapy. Assessment of the clinical and epidemiological characteristics of SARS-CoV-2 cases suggests the infected patients will not be contagious until the onset of severe symptoms and affects the other organs. Well-differentiated cells of apical airway epithelia communicating with ACE2 were promptly infected to SARS-CoV-2 virus. But the expression of ACE 2 in poorly differentiated epithelia facilitated SARS spike (S) protein-pseudo typed virus entry and it is replicated in polarized epithelia and especially exited via the apical surface. Limiting the transmission of COVID-19 infection & its prevention can be regarded as a hierarchy of controls. In this article, we briefly discuss the most recent advances in respect to aetiology, pathogenesis and clinical progression of the disease COVID-19.

scholarly journals The Effect of an Anthropogenic Magnetic Field on the Early Developmental Stages of Fishes—A Review

2021 ◽  
Vol 22 (3) ◽  
pp. 1210
Author(s):  
Krzysztof Formicki ◽  
Agata Korzelecka-Orkisz ◽  
Adam Tański
Keyword(s):  
Magnetic Fields ◽  
Developmental Stages ◽  
Negative Influence ◽  
Pigment Cells ◽  
Egg Activation ◽  
Industrial Equipment ◽  
Positive Effects ◽  
Early Developmental Stages ◽  
Species Specific ◽  
Early Developmental

The number of sources of anthropogenic magnetic and electromagnetic fields generated by various underwater facilities, industrial equipment, and transferring devices in aquatic environment is increasing. These have an effect on an array of fish life processes, but especially the early developmental stages. The magnitude of these effects depends on field strength and time of exposure and is species-specific. We review studies on the effect of magnetic fields on the course of embryogenesis, with special reference to survival, the size of the embryos, embryonic motor function, changes in pigment cells, respiration hatching, and directional reactions. We also describe the effect of magnetic fields on sperm motility and egg activation. Magnetic fields can exert positive effects, as in the case of the considerable extension of sperm capability of activation, or have a negative influence in the form of a disturbance in heart rate or developmental instability in inner ear organs.

scholarly journals Phylogenetic and Morphological Diversity of Cyanobacteria in Soil Desert Crusts from the Colorado Plateau

2001 ◽  
Vol 67 (4) ◽  
pp. 1902-1910 ◽  
Author(s):  
Ferran Garcia-Pichel ◽  
Alejandro López-Cortés ◽  
Ulrich Nübel
Keyword(s):  
Denaturing Gradient Gel Electrophoresis ◽  
Colorado Plateau ◽  
Morphological Diversity ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Filamentous Cyanobacteria ◽  
Phylogenetic Cluster ◽  
Field Samples ◽  
Gradient Gel Electrophoresis ◽  
Well Differentiated

ABSTRACT We compared the community structures of cyanobacteria in four biological desert crusts from Utah's Colorado Plateau developing on different substrata. We analyzed natural samples, cultures, and cyanobacterial filaments or colonies retrieved by micromanipulation from field samples using microscopy, denaturing gradient gel electrophoresis, and sequencing of 16S rRNA genes. While microscopic analyses apparently underestimated the biodiversity of thin filamentous cyanobacteria, molecular analyses failed to retrieve signals for otherwise conspicuous heterocystous cyanobacteria with thick sheaths. The diversity found in desert crusts was underrepresented in currently available nucleotide sequence databases, and several novel phylogenetic clusters could be identified. Morphotypes fitting the description of Microcoleus vaginatus Gomont, dominant in most samples, corresponded to a tight phylogenetic cluster of probable cosmopolitan distribution, which was well differentiated from other cyanobacteria traditionally classified within the same genus. A new, diverse phylogenetic cluster, named “Xeronema,” grouped a series of thin filamentousPhormidium-like cyanobacteria. These were also ubiquitous in our samples and probably correspond to various botanicalPhormidium and Schizothrix spp., but they are phylogenetically distant from thin filamentous cyanobacteria from other environments. Significant differences in community structure were found among soil types, indicating that soil characteristics may select for specific cyanobacteria. Gypsum crusts were most deviant from the rest, while sandy, silt, and shale crusts were relatively more similar among themselves.

scholarly journals Molecular Evolution of Tubulins in Diatoms

2022 ◽  
Vol 23 (2) ◽  
pp. 618
Author(s):  
Kirill V. Khabudaev ◽  
Darya P. Petrova ◽  
Yekaterina D. Bedoshvili ◽  
Yelena V. Likhoshway ◽  
Mikhail A. Grachev
Keyword(s):  
Amino Acids ◽  
Posttranslational Modification ◽  
Molecular Mechanisms ◽  
Morphological Diversity ◽  
Amino Acid Sequences ◽  
Transcriptome Data ◽  
Eukaryotic Proteins ◽  
Large Diatom ◽  
Species Specific ◽  
Β Tubulin

Microtubules are formed by α- and β-tubulin heterodimers nucleated with γ-tubulin. Tubulins are conserved eukaryotic proteins. Previously, it was shown that microtubules are involved in diatom silica frustule morphogenesis. Diatom frustules are varied, and their morphology is species-specific. Despite the attractiveness of the problem of elucidating the molecular mechanisms of genetically programmed morphogenesis, the structure and evolution of diatom tubulins have not been studied previously. Based on available genomic and transcriptome data, we analyzed the phylogeny of the predicted amino acid sequences of diatom α-, β- and γ-tubulins and identified five groups for α-tubulins, six for β-tubulins and four for γ-tubulins. We identified characteristic amino acids of each of these groups and also analyzed possible posttranslational modification sites of diatom tubulins. According to our results, we assumed what changes occurred in the diatom tubulin structures during their evolution. We also identified which tubulin groups are inherent in large diatom taxa. The similarity between the evolution of diatom tubulins and the evolution of diatoms suggests that molecular changes in α-, β- and γ-tubulins could be one of the factors in the formation of a high morphological diversity of diatoms.

scholarly journals Interleukin-17A induces bicarbonate secretion in normal human bronchial epithelial cells

2009 ◽  
Vol 296 (2) ◽  
pp. L257-L266 ◽  
Author(s):  
James L. Kreindler ◽  
Carol A. Bertrand ◽  
Robert J. Lee ◽  
Thomas Karasic ◽  
Shean Aujla ◽  
...  
Keyword(s):  
Cystic Fibrosis ◽  
Ion Transport ◽  
Antimicrobial Peptide ◽  
Basolateral Membrane ◽  
Chloride Secretion ◽  
Bicarbonate Secretion ◽  
Immune Functions ◽  
Bronchial Epithelial ◽  
Interleukin 17A ◽  
Well Differentiated

The innate immune functions of human airways include mucociliary clearance and antimicrobial peptide activity. Both functions may be affected by changes in epithelial ion transport. Interleukin-17A (IL-17A), which has a receptor at the basolateral membrane of airway epithelia, is a T cell cytokine that has been shown to increase mucus secretion and antimicrobial peptide production by human bronchial epithelial (HBE) cells. Furthermore, IL-17A levels are increased in sputum from patients during pulmonary exacerbations of cystic fibrosis. Therefore, we investigated the effects of IL-17A on basal, amiloride-sensitive, and forskolin-stimulated ion transport in mature, well-differentiated HBE cells. Exposure of HBE monolayers to IL-17A for 48 h induced a novel forskolin-stimulated bicarbonate secretion in addition to forskolin-stimulated chloride secretion and resulted in alkalinization of liquid on the mucosal surface of polarized cells. IL-17A-induced bicarbonate secretion was cystic fibrosis transmembrane conductance regulator (CFTR)-dependent, mucosal chloride-dependent, partially Na+-dependent, and sensitive to serosal, but not mucosal, stilbene inhibition. These data suggest that IL-17A modulates epithelial bicarbonate secretion and implicate a mechanism by which airway surface liquid pH changes may be abnormal in cystic fibrosis.

scholarly journals ACE2 Receptor Expression and Severe Acute Respiratory Syndrome Coronavirus Infection Depend on Differentiation of Human Airway Epithelia

2005 ◽  
Vol 79 (23) ◽  
pp. 14614-14621 ◽  
Author(s):  
Hong Peng Jia ◽  
Dwight C. Look ◽  
Lei Shi ◽  
Melissa Hickey ◽  
Lecia Pewe ◽  
...  
Keyword(s):  
Severe Acute Respiratory Syndrome ◽  
Receptor Expression ◽  
Pseudotyped Virus ◽  
Apical Surface ◽  
Sars Coronavirus ◽  
Airway Epithelia ◽  
S Protein ◽  
Human Airway ◽  
Well Differentiated ◽  
Human Airway Epithelia

ABSTRACT Studies of patients with severe acute respiratory syndrome (SARS) demonstrate that the respiratory tract is a major site of SARS-coronavirus (CoV) infection and disease morbidity. We studied host-pathogen interactions using native lung tissue and a model of well-differentiated cultures of primary human airway epithelia. Angiotensin converting enzyme 2 (ACE2), the receptor for both the SARS-CoV and the related human respiratory coronavirus NL63, was expressed in human airway epithelia as well as lung parenchyma. As assessed by immunofluorescence staining and membrane biotinylation, ACE2 protein was more abundantly expressed on the apical than the basolateral surface of polarized airway epithelia. Interestingly, ACE2 expression positively correlated with the differentiation state of epithelia. Undifferentiated cells expressing little ACE2 were poorly infected with SARS-CoV, while well-differentiated cells expressing more ACE2 were readily infected. Expression of ACE2 in poorly differentiated epithelia facilitated SARS spike (S) protein-pseudotyped virus entry. Consistent with the expression pattern of ACE2, the entry of SARS-CoV or a lentivirus pseudotyped with SARS-CoV S protein in differentiated epithelia was more efficient when applied to the apical surface. Furthermore, SARS-CoV replicated in polarized epithelia and preferentially exited via the apical surface. The results indicate that infection of human airway epithelia by SARS coronavirus correlates with the state of cell differentiation and ACE2 expression and localization. These findings have implications for understanding disease pathogenesis associated with SARS-CoV and NL63 infections.

scholarly journals Revealing sound-induced motion patterns in fish hearing structures in 4D: A standing wave tube-like setup designed for high-resolution time-resolved tomography

2021 ◽  
Author(s):  
Isabelle P. Maiditsch ◽  
Friedrich Ladich ◽  
Martin Heß ◽  
Christian M. Schlepütz ◽  
Tanja Schulz-Mirbach
Keyword(s):  
Standing Wave ◽  
Morphological Diversity ◽  
Wave Tube ◽  
Time Resolved ◽  
Motion Patterns ◽  
Bony Fishes ◽  
Spatial Dimensions ◽  
Spatio Temporal ◽  
Standing Wave Tube ◽  
Fish Hearing

Modern bony fishes possess a high morphological diversity in the auditory structures and their auditory capabilities. Yet, our knowledge of how the auditory structures such as the otoliths in the inner ears and the swim bladder work together remains elusive. Gathering experimental evidence on the in-situ motion of fish auditory structures while avoiding artifacts caused by surgical exposure of the structures has been challenging for decades. Synchrotron radiation-based tomography with high spatio-temporal resolution allows to study morphofunctional issues non-invasively in an unprecedented way. We therefore aimed to develop an approach that characterizes the moving structures in 4D (= three spatial dimensions+time). We designed a miniature standing wave tube-like setup to meet both the requirements of tomography and those of tank acoustics. With this new setup, we successfully visualized the motion of isolated otoliths and the auditory structures in zebrafish (Danio rerio) and the glass catfish (Kryptopterus vitreolus).

scholarly journals Regulation of dynamic pigment cell states at single-cell resolution

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Margherita Perillo ◽  
Nathalie Oulhen ◽  
Stephany Foster ◽  
Maxwell Spurrell ◽  
Cristina Calestani ◽  
...  
Keyword(s):  
Single Cell ◽  
Pigment Cell ◽  
Cell Types ◽  
Pigment Cells ◽  
Immune Functions ◽  
New Members ◽  
Evolutionary Selection ◽  
Purple Sea Urchin ◽  
Coelomic Cells

Cells bearing pigment have diverse roles and are often under strict evolutionary selection. Here, we explore the regulation of pigmented cells in the purple sea urchin Strongylocentrotus purpuratus, an emerging model for diverse pigment function. We took advantage of single cell RNA-seq (scRNAseq) technology and discovered that pigment cells in the embryo segregated into two distinct populations, a mitotic cluster and a post-mitotic cluster. Gcm is essential for expression of several genes important for pigment function, but is only transiently expressed in these cells. We discovered unique genes expressed by pigment cells and test their expression with double fluorescence in situ hybridization. These genes include new members of the fmo family that are expressed selectively in pigment cells of the embryonic and in the coelomic cells of the adult - both cell-types having immune functions. Overall, this study identifies nodes of molecular intersection ripe for change by selective evolutionary pressures.

The pollen metamorphosis phenomenon in Panax ginseng, Aralia elata and Oplopanax elatus; an addition to discussion concerning the Panax affinity in Araliaceae

Zygote ◽  
2009 ◽  
Vol 17 (1) ◽  
pp. 1-17 ◽  
Author(s):  
Arkadiy A. Reunov ◽  
Galina D. Reunova ◽  
Yana N. Alexandrova ◽  
Tamara I. Muzarok ◽  
Yuriy N. Zhuravlev
Keyword(s):  
Morphological Characteristics ◽  
Pollen Grains ◽  
Morphological Diversity ◽  
Average Diameter ◽  
Aralia Elata ◽  
Phylogenetic Perspective ◽  
Oplopanax Elatus ◽  
Species Specific ◽  
Structural Mechanisms ◽  
Size Diminution

SummaryTo find more morphological characteristics useful for discussion on aralian or non-aralian Panax affinity, pollen morphological diversity was comparatively analysed in P. ginseng, Aralia elata and Oplopanax elatus collected during their pollination periods. In the anthers of both the buds and open flowers, the pollen average diameter varied between some species-specific maximum and minimal measurement. However, the larger pollen grains were typically found in the buds whereas the smaller pollen prevailed in the open flowers, testifying to the pollen size diminution during anther maturation. Based on this finding, the subsequent examination of pollen according to size decrease was put into operation as a method of pollen modification for the study. The structural mechanisms of pollen metamorphosis were identified as not being species specific but rather universal. These mechanisms are suggested to be the shrinkage of the pollen vegetative cytoplasm, the intine enlargement, the deepening of three colporate apertures provided by exine sunken into enlarged intine areas, the aperture accretion as well as the transformation of the exine from thick/sculptured into thin/less sculptured. During ‘size-reducing metamorphosis’, the pollen grains changed dramatically, going through a species-specific set of intermediate morphs to the final species-specific morphotype. In P. ginseng this morphotype is round (diameter is about 16 μm), in A. elata it is round with a single projection (diameter is about 15 μm) and in O. elatus it is ovoid with a single projection (average diameter is about 18 μm). In addition, every species is peculiar in having the unique vegetative cytoplasm inclusions and individual construction of the largest pollen exine. From a phylogenetic perspective, these findings presumably add support to the option of equal remoteness of P. ginseng from A. elata and O. elatus. The characteristics found seem to be suitable for examination of Panax affinity, by the subsequent study of more Araliaceae representatives.

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