A Study of Retinal Development in Larval Herring and Sole

1980 ◽  
Vol 60 (1) ◽  
pp. 59-71 ◽  
Author(s):  
Jennifer M. Sandy ◽  
J. H. S. Blaxter
Keyword(s):  
Outer Layer ◽  
Light Microscope ◽  
Retinal Development ◽  
Visual Cell ◽  
Adult Fish ◽  
Cell Nuclei ◽  
Larval Life ◽  
Paraffin Sections ◽  
Early Stages

It is known from earlier work (Blaxter & Jones, 1967; Blaxter, 1968a; Blaxter & Staines, 1970) that the larvae of many species of teleost have a pure-cone retina. The rods only appear well after hatching and often as late as metamorphosis. This means that much of the larval life may be spent without fully developed eyes. The rods are difficult to resolve under the light microscope using paraffin sections (about 5 µm) and it is therefore easier to compare the number of cones with the prominent visual cell nuclei in the outer layer (ONL) in such preparations. The ratio has been found to be 1:1 in the early stages and changes as the rods develop, reaching ratios of 1:15 or more in adult fish. Thus, for every cone there may be 14 or more rods.

Reproduction

2017 ◽  
Author(s):  
Derek Burton ◽  
Margaret Burton
Keyword(s):  
Reproductive Behaviour ◽  
Life Cycles ◽  
Freshwater Species ◽  
Adult Fish ◽  
Reproductive Patterns ◽  
Cell Divisions ◽  
Early Stages ◽  
External Cues ◽  
Neural Factors

Interspecific fish reproductive patterns, outputs and life cycles display the greatest variability within the vertebrates. Early stages of oogenesis can be repeated in adult fish, contrasting with mammals; the pre-set sequence of cell divisions in gametogenesis is otherwise similar and is described in detail. Most fish deposit much yolk (vitellogenesis) in developing eggs. Migrations, beach-spawning and mouth-brooding are some of the interesting variations. Fertilization is predominantly external but is internal in some groups such as chondrichthyans. The omission of annual reproduction is well established in some freshwater species and the idea that this may also be the case for marine teleosts is gaining acceptance. This should be taken into account for intensively fished species. The possible roles of external cues, hormones, pheromones and neural factors acting as ‘switches’ and coordinators in gametogenesis and reproductive behaviour are discussed.

Differential accumulation of oocyte nuclear proteins by embryonic nuclei of Xenopus

Development ◽  
1987 ◽  
Vol 101 (4) ◽  
pp. 829-846 ◽  
Author(s):  
C. Dreyer
Keyword(s):  
De Novo ◽  
Germinal Vesicle ◽  
Intrinsic Property ◽  
Nuclear Proteins ◽  
Cell Nuclei ◽  
Germinal Vesicle Breakdown ◽  
Early Stages ◽  
Nuclear Antigens ◽  
Gradual Process ◽  
Oocyte Nuclear Proteins

Oocyte nuclear proteins of Xenopus are distributed into the cytoplasm of the maturing egg after germinal vesicle breakdown. Later they are found in all cell nuclei of the embryo. At early stages of development, different nuclear proteins behave differently. A class of ‘early shifting’ antigens is accumulated by pronuclei and cleavage nuclei, whereas others appear to be excluded from the nuclei at early stages but are shifted into the nuclei at blastula or during and after gastrulation. Accumulation of ‘late-shifting’ nuclear antigens is a gradual process and occurs during a period characteristic of each protein. Multiple artificial pronuclei can be formed after injection of sperm nuclei, erythrocyte nuclei or pure lambda-DNA into unfertilized eggs. The artificial pronuclei accumulate early- but not late-shifting proteins. Early-migrating proteins rapidly accumulate into the germinal vesicle after de novo synthesis in the oocyte, indicating that the efficiency of translocation into nuclei is an intrinsic property of each protein. Artificial extension of the length of the cell cycle before midblastula transition does not lead to accumulation of the late-shifting nuclear antigens investigated.

Histochemical characteristics of the metacercarial cyst wall of Gynaecotyla adunca

1995 ◽  
Vol 69 (3) ◽  
pp. 223-228
Author(s):  
J. Lee ◽  
M.A. Medlin ◽  
S.T. Dunn
Keyword(s):  
Outer Layer ◽  
Cyst Wall ◽  
Light Microscope ◽  
Structural Modification ◽  
Microscope Level ◽  
Histochemical Analysis ◽  
Light Microscope Level ◽  
Metacercarial Cyst

AbstractThe cyst wall of the metacercaria of Gynaecotyla adunca (Microphallidae: Digenea) was subjected to comprehensive histochemical analysis. At the light microscope level, a uniformly thick, bipartite cyst wall, probably wholly of parasite origin, was evident. Structural modification of the cyst wall to provide an escape aperture was not apparent. The thicker, inner layer was comprised of phospholipid and glyco- and/or mucoproteins, possibly similar in structure to collagen. The outer layer was highly proteinaceous and contained additional amounts of acidic and neutral mucosubstances. The results are discussed in the context of previous observations regarding the excystment requirements of this microphallid species.

scholarly journals Early stages of retinal development depend on Sec13 function

Biology Open ◽  
2013 ◽  
Vol 2 (3) ◽  
pp. 256-266 ◽  
Author(s):  
K. Schmidt ◽  
F. Cavodeassi ◽  
Y. Feng ◽  
D. J. Stephens
Keyword(s):  
Retinal Development ◽  
Early Stages

scholarly journals Intranuclear Inclusions in Multiple Myeloma and Macroglobulinemia

Blood ◽  
1963 ◽  
Vol 21 (3) ◽  
pp. 335-351 ◽  
Author(s):  
GEOFFREY M. BRITTIN ◽  
YASUKAZU TANAKA ◽  
GEORGE BRECHER
Keyword(s):  
Multiple Myeloma ◽  
Bone Marrow ◽  
Electron Microscope ◽  
Serum Protein ◽  
Plasma Cell ◽  
Inclusion Bodies ◽  
Intranuclear Inclusions ◽  
Nuclear Inclusion ◽  
Cell Nuclei ◽  
Paraffin Sections

Abstract Inclusion bodies in plasma cell nuclei of six patients with multiple myeloma and of three patients with macroglobulinemia have been studied histochemically. In three cases they have been studied with the electron microscope. The inclusions are readily identified in Giemsa stained smears of bone marrow and in paraffin sections. Their PAS positivity may be related to the hexose content of the patient’s abnormal serum protein. Evidence is presented that the inclusions are true nuclear inclusion bodies, that they represent nuclear elaboration of glycoprotein, and that they may be found in all three immunoelectrophoretic varieties of multiple myeloma, as well as in macroglobulinemia.

scholarly journals APOPTOSIS CELLS OF CORONARY ARTERY WALL AS DEVELOPING AND PROGRESSING FACTOR OF CORONARY SCLEROSIS

2013 ◽  
Vol 68 (9) ◽  
pp. 22-26
Author(s):  
T. E. Vladimirskaya ◽  
I. A. Shved ◽  
S. G. Krivorot
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Coronary Artery ◽  
Smooth Muscle Cells ◽  
Coronary Arteries ◽  
Muscle Cells ◽  
Artery Wall ◽  
Paraffin Sections ◽  
Early Stages ◽  
Coronary Artery Wall

Objective: to study apoptosis of individual cellular components of the vascular wall of coronary arteries at different morphological stages of atherosclerosis. Material and methods. The study was performed on coronary arteries taken from 52 deceased patients with atherosclerosis and coronary heart disease at different stages of atherogenesis. For morphological study prepared paraffin sections, which were stained for morphological studies were prepared paraffin sections, which were stained with hematoxylin and eosin, by Van Gieson, Masson, on lipids with Sudan black B, according to Van Cossu. .To determine apoptosis, TUNEL method used in paraffin sections. Apoptotic index (AI) was calculated by TUNEL-positive cells and the average inner shell coronary artery around the perimeter each with increasing microscopic 1000. Results. Investigation showed significant apoptosis (p 0.05) increase in AI smooth muscle, endothelial cells, macrophages in the coronary arteries affected by atherosclerosis compared to intact control group vascular segments significant reduction AI endothelial, smooth muscle cells and macrophages (p  0,05) traced from the early stages of atherogenic disorders to atheromatosis. Conclusions. It is established that apoptosis of smooth muscle cells, macrophages and endothelial cells is the most intensive on early stages of atherosclerotic process. In process of progressing of atherosclerosis intensity and prevalence of apoptosis of coronary artery wall cells decreases, and processes of necrosis becomes predominant. Apoptosis of coronary artery wall cells is valuable in increasing the zones of atheromatosis, plaque destabilizations, and also increases the risk of thrombosis and ulcerations. 

scholarly journals Microscophy Identification of Toxocara cati First Stage Larvae and Second Stage Larvae

2019 ◽  
Vol 3 (1) ◽  
pp. 1
Author(s):  
Eny Coolfina Simarmata ◽  
Kusnoto Kusnoto ◽  
Mochamad Lazuardi ◽  
Setiawan Koesdarto ◽  
Endang Suprihati ◽  
...  
Keyword(s):  
Outer Layer ◽  
Light Microscope ◽  
Adult Stage ◽  
Anterior Part ◽  
Posterior Part ◽  
Middle Layer ◽  
Toxocara Cati ◽  
Structural Morphology ◽  
Second Stage ◽  
The Third

This study was aimed to identify the ultra structural morphology of Toxocara cati First Stage Larvae and Second Stage Larvae using Light Microscope. Toxocara cati larvae were obtained from adult worm eggs then were treated in phospat buffer saline with comparasion 1 : 1 until it reached the stage of larvae 1 and 2. The shell of egg Toxocara cati were thick and usually consist of three layers. The first layer was inner membrane, the second layer was middle layer and the third was outer layer. The results of larvae morphology that were identified using light microscope showed that the anterior part of Toxocara cati first stage larvae has a dorsal lip and esophagus and intestine on the posterior part but it could not be identified perfectly. The anterior part of Toxocara cati second stage larvae that were identified has three lips that leads directly into the oesophagus. Three lips on the anterior part of Toxocara cati larvae 2 consist of a dorsal lip and two subventral lips. Morphological of Toxocara cati larvae similar with the Toxocara cati adult worms because morphology of larvae and adult stage was difficult to differentiated.

scholarly journals Formation Mechanism of Aluminide Diffusion Coatings on Ti and Ti-6Al-4V Alloy at the Early Stages of Deposition by Pack Cementation

Materials ◽  
2019 ◽  
Vol 12 (19) ◽  
pp. 3097
Author(s):  
Hailiang Du ◽  
Ning Tan ◽  
Li Fan ◽  
Jiajie Zhuang ◽  
Zhichao Qiu ◽  
...  
Keyword(s):  
Outer Layer ◽  
Aluminide Coating ◽  
Energy Dispersive Spectrometer ◽  
Pack Cementation ◽  
X Ray Diffraction ◽  
Diffusion Coatings ◽  
Early Stages ◽  
Outward Migration ◽  
Kinetics Of ◽  
Precision Balance

The diffusion coatings were deposited on commercially pure Ti and Ti-6Al-4V alloy at up to 1000 °C for up to 10 h using the pack cementation method. The pack powders consisted of 4 wt% Al (Al reservoir) and 4 wt% NH4Cl (activator) which were balanced with Al2O3 (inert filler). The growth kinetics of coatings were gravimetrically measured by a high precision balance. The aluminised specimens were characterised by means of scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and X-ray diffraction (XRD). At the early stages of deposition, a TiO2 (rutile) scale, other than aluminide coating, was developed on both materials at <900 °C. As the experimental temperature arose above 900 °C, the rutile layer became unstable and reduced to the low oxidation state of Ti oxides. When the temperature increased to 1000 °C, the TiO2 scale dissociated almost completely and the aluminide coating began to develop. After a triple-layered coating was generated, the coating growth was governed by the outward migration of Ti species from the substrates and obeyed the parabolic law. The coating formed consisted of an outer layer of Al3Ti, a mid-layer of Al2Ti and an inner layer of AlTi. The outer layer of Al3Ti dominated the thickness of the aluminide coating.

scholarly journals Cüce Hamsterlerin (Phodopus roborovskii) Genital Dokularında Androjen Reseptör Lokalizasyonu

2018 ◽  
Vol 6 (4) ◽  
pp. 415
Author(s):  
Fatih Mehmet Gür ◽  
Sema Timurkaan ◽  
Saime Betül Baygeldi ◽  
Zait Ender Özkan ◽  
Yeşim Aslan Kanmaz ◽  
...  
Keyword(s):  
Prostate Gland ◽  
The Body ◽  
Antigen Retrieval ◽  
Cell Nuclei ◽  
Paraffin Sections ◽  
Dwarf Hamster ◽  
Positive Immunostaining ◽  
Neutral Formalin ◽  
Female Genital ◽  
Male Dwarf

Androgens perform the their effects on target tissues mainly through the androgen receptor (AR). In this study, AR localization was investigated in female and male dwarf hamsters genital tissues. In the present study, 6 female and 6 male animals were used. After anesthesia, the tissues to be worked were quickly removed from the body and fixed in 10% buffered neutral formalin, and embedded in paraffin. Sections were stained after microwave antigen retrieval for immunohistochemistry. Although AR positive immunostaining was observed only in cell nuclei in testis, caput epididymis, prostate gland and vesicle seminalis tissues, it was observed in cytoplasm or nucleus of the cells in the ovarium and oviduct tissues. AR localization in dwarf hamster male and female genital tissues was similar to other species. The presence of AR in genital tissues supports the idea that androgens are essential for these tissues.

scholarly journals Tbx12, a novel T-box gene, is expressed during early stages of heart and retinal development

2000 ◽  
Vol 96 (1) ◽  
pp. 137-140 ◽  
Author(s):  
Christian T Carson ◽  
Eric R Kinzler ◽  
Brian A Parr
Keyword(s):  
Retinal Development ◽  
T Box ◽  
Early Stages
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