The Genital System of Temnocephala. I. Ultrastructural Features of the Differentiating Spermatid of Temnocephala Novaezealandiae, Including Notes on a Possible Correlation Between Cellular Autophagy and Mitochondrial Function.

1983 ◽  
Vol 31 (3) ◽  
pp. 317 ◽  
Author(s):  
JB Williams
Keyword(s):  
Mitochondrial Function ◽  
Sperm Morphology ◽  
Lamellar Body ◽  
Glycogen Metabolism ◽  
Basal Bodies ◽  
Genital System ◽  
Nuclear Region ◽  
Cellular Autophagy ◽  
Early Spermatid

The early spermatid of I: novaezealandiae possesses two centrioles, between which lies a transient lamellar body. The centrioles form the basal bodies of two flagella of the '9+1' type, which remain free throughout spermatogenesis. Following cell elongation and organelle migration, the advanced spermatid is composed of a proximal cytoplasmic mass, a greatly attenuated nuclear region, an elongated mid-piece, an end piece, and the subterminally inserted flagella. There is no acrosome. Rows of glycogen granules occur in the spermatid shaft. Extrusion of nuclear components probably contributes to the modelling and compaction of the nucleus. The mitochondria of the cytoplasmic mass possess indentations filled with membrane whorls; it is proposed that the membrane accumulates in cellular autophagy. Mitochondria in the spermatid shaft are also indented; perhaps autophagic vesicles occupying the invaginations are related to glycogen metabolism. Modified membranes lining the indentations may be sites for the entry of lytic products into the mitochondria. Knowledge of the sperm morphology of Temnocephala assists in the determination of the taxonomic position of the genus.

The Genital System of Temnocephala II.* Further Observations on theSpermatogenesis of Temnocephala novaezealandiae, with particular Reference to the Mitochondria

1984 ◽  
Vol 32 (4) ◽  
pp. 447 ◽  
Author(s):  
JB Williams
Keyword(s):  
Sperm Cell ◽  
Lamellar Body ◽  
Mirror Image ◽  
Genital System ◽  
Long Period ◽  
Dense Bodies ◽  
Cellular Autophagy ◽  
Cell Processes ◽  
Spiral Array ◽  
Chromatoid Bodies

The testis is bounded by a modified epithelium which has strongly phagocytic properties. Cells at synchronized stages of development are united in syncytia but do not form rosettes; the clusters of joined cells are enveloped by epithelial cell processes. A relatively long period of synapsis characterizes the primary spermatocytes. The nucleus passes through a racquet-shaped configuration as it commences to elongate, and later the compacted chromatin transforms into helically wound strands. At the time of centriole reorientation, the intercentriolar lamellar body divides down the middle, separating the mirror-image halves. Components of the intercentriolar body may give rise to the dense centriole caps. The peripheral microtubules form a spiral array in certain segments of the elongated sperm cell, and dense bodies with paracrystalline centres are regularly aligned in the shaft. When chromatoid bodies of animal spermatozoa are associated with aggregated, indented mitochondria. they are probably in process of degradation by cellular autophagy.

Spermatogenesis and the fine structure of the mature spermatozoon of the liver fluke, Fasciola hepatica (Trematoda: Digenea)

Parasitology ◽  
1990 ◽  
Vol 101 (3) ◽  
pp. 395-407 ◽  
Author(s):  
A. W. Stitt ◽  
I. Fairweather
Keyword(s):  
Fine Structure ◽  
Liver Fluke ◽  
Central Body ◽  
Fasciola Hepatica ◽  
Mature Spermatozoon ◽  
Basal Bodies ◽  
Nuclear Region ◽  
Sperm Ultrastructure ◽  
Transmission Electron ◽  
Median Process

SUMMARYSpermatogenesis and the fine structure of the mature spermatozoon of Fasciola hepatica have been studied by transmission electron microscopy. The primary spermatogonia display a typical gonial morphology and occupy the periphery of the testis. They undergo 3 mitotic divisions to give rise to 8 primary spermatocytes forming a rosette of cells connected to a central cytophore. The primary spermatocytes undergo 2 meiotic divisions, resulting in 32 spermatids that develop into spermatozoa. Intranuclear synaptonemal complexes in primary spermatocytes confirm the first meiotic division. The onset of spermiogenesis is marked by the formation of the zone of differentiation which contains 2 basal bodies and a further centriole derivative, the central body. The zone extends away from the spermatid cell to form the median process; into this migrates the differentiated and elongate nucleus. Simultaneously, 2 axonemes develop from the basal bodies. During development, they rotate through 90° to extend parallel to the median process. The migration of the nucleus to the distal end of the median process coincides with the fusion of the axonemes to the latter to form a monopartite spermatozoon. The mature spermatozoon possesses 2 axonemes of the 9 + ‘1’ pattern typical of parasitic platyhelminths, 2 elongate mitochondria and a variable array of peripheral microtubules. The nuclear region of the spermatozoon is immotile. The value of sperm ultrastructure as a taxonomic tool in platyhelminth phylogeny is discussed.

scholarly journals Basophilic Lamellar Systems in the Crayfish Spermatocyte

1958 ◽  
Vol 4 (3) ◽  
pp. 267-274 ◽  
Author(s):  
August Ruthmann
Keyword(s):  
Electron Microscopy ◽  
Small Rna ◽  
Meiotic Prophase ◽  
Lamellar Body ◽  
Annulate Lamellae ◽  
Late Prophase ◽  
Lamellar System ◽  
Thin Sections ◽  
Early Spermatid ◽  
Break Up

Histochemical procedures for the demonstration of RNA have shown the presence of intensely basophilic bodies in the cytoplasm of spermatocytes of the crayfish, Cambarus virilis. The staining of thick sections, cut alternately with thin sections for electron microscopy, has permitted identification of the basophilic bodies with two types of lamellar systems. One of these, a set of straight annulate lamellae, is restricted to meiotic prophase. The second type of lamellar systems has been found from late prophase to early spermatid stages. It consists of an ellipsoidal lamellar set which intersects a number of straight lamellae. Within the region of intersection, the ellipsoidal lamellae break up into an array of small tubules of about 150 A diameter. The term tubulate lamellar system was chosen to designate this type of lamellar complex. Small RNA-containing granules could not be detected in annulate lamellar systems. While there are a few granules in the marginal regions of the tubulate lamellar system, their distribution cannot be responsible for the basophilia which is intense within all regions of the lamellar body.

Non-invasive Prenatal Determination of Fetal Maturity

2016 ◽  
Vol 70 (3) ◽  
pp. 153-157
Author(s):  
Elena Dzikova ◽  
Goran Dimitrov ◽  
Olivera Stojceva-Taneva
Keyword(s):  
Gestational Age ◽  
Lamellar Body ◽  
Invasive Technique ◽  
Non Invasive ◽  
Gynecology And Obstetrics ◽  
Fetal Maturity ◽  
Invasive Method ◽  
The University ◽  
Body Count

Abstract Aims. The prenatal prediction of fetal maturity is very important, since neonatal respiratory distress syndrome (RDS) is one of the biggest causes of neonatal mortality. Our aim was to investigate a new non-invasive method for prediction of fetal maturity and to determine in which group according to gestational age of the fetus, the treatment works the best and in which cases it is necessary to be repeated. Methods. We examined 60 patients (30 with impending preterm delivery, divided in 3 groups: 28-30, 30-32, and 32-34 gestational weeks and 30 controls), at the University Clinic for Gynecology and Obstetrics, Medical Faculty, University “Ss. Cyril and Methodius”, Skopje, R. Macedonia. Fetal maturity was examined using ultrasound histogram from fetal lungs and liver, correlated with gestational age and postpartum RDS. Where possible, we performed amniocentesis for lamellar body count (LBC) to correlate our results with the current invasive method for prediction of fetal maturity. Results. Pre-therapy investigation showed a strong fetal immaturity in 28-32 weeks of gestation and less evident fetal immaturity in 32-34 weeks of gestation. Seventy-two hours post-treatment, fetal maturation was low in the first group, higher in the second and the highest in the third group. Amniocentesis for LBC showed correlation with the ultrasound results. Postpartum results were correlated with pre-delivery ultrasound and showed significance of p <0.05. Conclusion. The results obtained in our study were with high significance, and they were in correlation with other similar studies. However, more extensive investigations should be made to replace the current invasive technique.

scholarly journals AN ULTRASTRUCTURAL STUDY OF PLANT SPERMATOGENESIS

1968 ◽  
Vol 37 (2) ◽  
pp. 370-393 ◽  
Author(s):  
F. R. Turner
Keyword(s):  
Electron Microscopy ◽  
Golgi Apparatus ◽  
Ultrastructural Study ◽  
Light And Electron Microscopy ◽  
Mature Sperm ◽  
Basal Bodies ◽  
Animal Cells ◽  
Early Spermatid ◽  
And Behavior ◽  
Cytoskeletal System

Spermatogenesis in the charophyte Nitella has been followed in antheridia prepared for light and electron microscopy. The antheridial filament cells contain paired centrioles which are similar in structure and behavior to the centrioles of animal cells. In the early spermatid, the centrioles undergo an initial elongation at their distal ends and become joined by a spindle-shaped fibrous connection. At the same time, their proximal ends are closely associated with the development of a layer of juxtaposed microtubules which will form the microtubular sheath. The architectural arrangement of these microtubules suggests that they constitute a cytoskeletal system, forming a framework along which the mitochondria and plastids become aligned and along which the nucleus undergoes extensive elongation and differentiation. The microtubular sheath persists in the mature sperm. During mid-spermatid stages, the centrioles give rise to the flagella and concomitantly undergo differentiation to become the basal bodies. The Golgi apparatus goes through a period of intensive activity during mid-spermatid stages, then decreases in organization until it can no longer be detected in the late spermatid. An attempt is made to compare similarities between plant and animal spermiogenesis.

scholarly journals Improvement of Rat Survival and Liver Mitochondrial Function in Biliary Obstruction After Treatment With Sodium Thiosulfate

HPB Surgery ◽  
1995 ◽  
Vol 8 (4) ◽  
pp. 249-252
Author(s):  
B. Myslovaty ◽  
S. Kyzer ◽  
H. Levinsky ◽  
C. Chaimoff
Keyword(s):  
Survival Rate ◽  
Liver Function ◽  
Mitochondrial Function ◽  
Mitochondrial Respiration ◽  
Biliary Obstruction ◽  
Sodium Thiosulfate ◽  
Sodium Thiosulphate ◽  
Respiratory Capacity ◽  
Effect Of Treatment

The exact cause of liver failure occurring after long standing biliary obstruction is not known. Impairment of hepatic mitochondrial respiration was postulated in some studies. Sodium thiosulphate (STS) is known to have a protective effect on liver function during administration of hepatotoxic chemotherapy. In the present experimental study the effect of treatment with STS in the presence of obstructive jaundice was studied by determination of the survival rate of rats subjected to biliary obstruction and by polarographic determination of the hepatic mitochondrial function. Treatment with STS was found to result in a significant improvement in rats' survival rate (p < 0.05). Polarography demonstrated significant preservation of mitochondrial respiratory capacity after treatment with STS. The results of the present study show that the deterioration in liver function in the presence of biliary obstruction is probably caused by impairment of mitochondrial respiration. This may be preserved by treatment with STS. The exact explanation of its effect is not yet clear.

Determination of Lamellar Body Phospholipids in Amniotic Fluid: A Method to Predict when the Fetal Lung Becomes Mature

1986 ◽  
Vol 21 (2) ◽  
pp. 64-69 ◽  
Author(s):  
A. Beintema-Dubbeldam ◽  
Bennebroek Gravenhorst ◽  
J. Egberts
Keyword(s):  
Amniotic Fluid ◽  
Lamellar Body ◽  
Fetal Lung

ACTION OF PINEAL EXTRACTS ON THE GONADS AND THEIR FUNCTION

1963 ◽  
Vol 27 (1) ◽  
pp. 107-118 ◽  
Author(s):  
M. REISS ◽  
R. H. DAVIS ◽  
M. B. SIDEMAN ◽  
I. MAUER ◽  
E. S. PLICHTA
Keyword(s):  
Inhibitory Effect ◽  
Laboratory Animals ◽  
Genital System ◽  
Weight Changes ◽  
Test Animal ◽  
Short Term ◽  
Trichloracetic Acid ◽  
Pineal Extracts ◽  
Phosphorus Turnover

SUMMARY The action of pineal extracts on the genital system of several species of laboratory animals has been investigated. Determination of the phosphorus turnover in the genital organs of treated animals proved to be a significant guide to the action of pineal preparations. Doses of pineal extracts lower than those required for weight changes sufficed to produce changes in phosphorus metabolism. Apparently contradictory results encountered originally were explained when findings were evaluated on the basis of the age of the test animal and the type of extract used. Thus, in immature and/or hypophysectomized animals, crude aqueous extracts stimulate the genital system, whereas in mature intact animals the same extract often has an inhibitory effect on the same organs. The inhibitory effect could be measured also in immature mice treated with gonadotrophic hormone and this proved useful in short-term experiments. Crude glandular suspensions apparently contain both inhibitory and stimulatory principles. Partial separation of these was achieved through the use of trichloracetic acid, the supernatant fluid having predominantly inhibitory action while the stimulatory substance was found mainly in the precipitate.

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