Ultrastructural changes in female hepatocytes during ovarian maturation of Steindachnerina insculpta (Pisces: Curimatidae)

During gonadal maturation the females of Steindachnerina insculpta, a teleost of the Furnas reservoir, Minas Gerais, Brazil, show low hepatosomatic and high gonadossomatic indexes, suggesting possible transference of hepatic substances to the ovaries. In comparison to the resting phase, in the maturation/mature one the hepatocytes show greater development of both smooth and rough endoplasmic reticula, increased electron density in the mitochondria, and glycogen scattered throughout the cytoplasm. In both resting and maturation/mature phases, the hepatic parenchyma contains melanomacrophagic centers that consist of degenerating cellular debris and are surrounded by capsules formed by cells, resembling fibroblasts, joined by desmosomes. No physiological relation of these centers with ovarian maturation was found.

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The ultrastructure of M1-a-mediated resistance to powdery mildew infection in barley

Canadian Journal of Botany ◽

10.1139/b75-286 ◽

1975 ◽

Vol 53 (22) ◽

pp. 2589-2597 ◽

Cited By ~ 10

Author(s):

H. H. Edwards

Keyword(s):

Powdery Mildew ◽

Host Cell ◽

Electron Density ◽

Epidermal Cells ◽

Dense Material ◽

Ultrastructural Changes ◽

Electron Dense Material ◽

Host Cytoplasm ◽

Powdery Mildew Infection ◽

Cell Protoplast

M1-a-mediated resistance in barley to invasion by the CR3 race of Erysiphe graminis f. sp. hordei does not occur in every host cell with the same speed and severity. In some cells ultrastructural changes within the host cell as a result of resistance will occur within 24 h after inoculation, whereas in other cells these changes may take up to 72 h. In some cells the ultrastructural changes are so drastic that they give the appearance of a hypersensitive death of the host cell, whereas in other cells the changes are very slight. In any case, at the end of these changes the fungus ceases growth. The ultrastructural changes occur in penetrated host epidermal cells as well as non-infected adjacent epidermal and mesophyll cells.The following ultrastructural changes have been observed: (1) an electron-dense material which occurs either free in the vacuole or adhering to the tonoplast (the material is granular or in large clumps); (2) an increased electron density of the host cytoplasm and nucleus; (3) a breakdown of the tonoplast so that the cytoplasmic constituents become dispersed throughout the cell lumen; and (4) the deposition of papillar-like material in areas other than the penetration site. The first three changes take place within the host cell protoplasts and are directly attributable to the gene M1-a. These changes are typical of stress or incompatibility responses and thus M1-a appears to trigger a generalized incompatibility response in the presence of race CR3. The papillar-like material occurs outside the host cell protoplast in the same manner as the papilla and probably is not directly attributable to M1-a.

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Effects of High Hydrostatic Pressure Processing on the Number of Bacteria and Texture of Beef Liver

Journal of Food Quality ◽

10.1155/2017/7835714 ◽

2017 ◽

Vol 2017 ◽

pp. 1-7 ◽

Cited By ~ 2

Author(s):

Hirokazu Ogihara ◽

Hodaka Suzuki ◽

Masaki Michishita ◽

Hitoshi Hatakeyama ◽

Yumiko Okada

Keyword(s):

Hydrostatic Pressure ◽

High Hydrostatic Pressure ◽

Ultrastructural Analysis ◽

Lower Pressure ◽

Mitochondrial Swelling ◽

Beef Liver ◽

High Hydrostatic Pressure Processing ◽

Rough Endoplasmic Reticula ◽

Endoplasmic Reticula ◽

Number Of Bacteria

Providing beef liver for raw consumption was banned in Japan on July 1, 2012. To lift the ban, the establishment of effective countermeasures for safe raw consumption is necessary. In this study, we examined the effects of high hydrostatic pressure processing on raw beef liver. Beef liver samples subjected to 300 MPa of pressure or higher for 10 min at 25°C became firmer and showed a paler color and were considered unsuitable for raw consumption. More than 3.0 log reductions of bacteria were seen after treatments at 400 and 500 MPa, but the treatment with lower pressure did not show enough microcidal effects for safe consumption. Histological and ultrastructural analysis revealed that high hydrostatic pressure processing increased mitochondrial swelling and reduced rough endoplasmic reticula in hepatocytes, and such changes might be related to the observed changes of texture in the treated raw beef liver.

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Fine structural observation on the oogenesis and vitellogenesis of the Chinese soft-shelled turtle (Pelodiseus sinensis)

Zygote ◽

10.1017/s0967199409990116 ◽

2009 ◽

Vol 18 (2) ◽

pp. 109-120 ◽

Cited By ~ 10

Author(s):

Hei Nainan ◽

Yang Ping ◽

Yang Yang ◽

Liu Jinxiong ◽

Bao Huijun ◽

...

Keyword(s):

Electron Microscopy ◽

Special Functions ◽

Dorsal Surface ◽

Sibling Relationship ◽

Follicular Epithelium ◽

Follicular Cells ◽

Cell Organelles ◽

Rough Endoplasmic Reticula ◽

Relationship Of ◽

Endoplasmic Reticula

SummaryFine structure observations were performed by means of electron microscopy on oogenesis and vitellogenesis and the special functions of follicular cells in the Chinese soft-shelled turtle (Pelodiseus sinensis). Histological examination of the ovary showed a well developed lacunae system containing fine granules, fibres or gelatiniform materials with one or two germinal beds dispersed on the dorsal surface of the ovarian cortex. The process of oogenesis comprised 10 consecutive phases according to the morphology of the yolk platelets, follicular cells and zona pellucida (ZP). Electron microscopy of vitellogenesis revealed some of the mitochondria gradually being transformed into yolk granules. In the advanced stage of vitellogenesis, large amounts of rough endoplasmic reticula, Golgiosomes and other cell organelles that are involved in synthesis and secretion were observed in follicular cells. The ZP was formed by microvilli, thus increasing the absorptive surface of the oocyte and facilitating transport of nutrients from the follicular epithelium to the ooplasm. This study demonstrated that the ovaries of members of the Testudinidae share more features with Archosaurs than with Squamates, indicating that these features were phylogenetically conserved in the Archosauria. The present observations suggest that the accumulation of yolk materials was controlled by the intrinsic and extrinsic pathways as well as by the activity of follicular cells. These results might also support a sibling relationship of the Testudinidae with the Archosauria and not with all extant reptiles.

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Reproduction of the catfish Iheringichthys labrosus (Lütken) (Pisces, Siluriformes) in Furnas reservoir, Minas Gerais, Brazil

Revista Brasileira de Zoologia ◽

10.1590/s0101-81752004000200006 ◽

2004 ◽

Vol 21 (2) ◽

pp. 193-200 ◽

Cited By ~ 19

Author(s):

José Enemir dos Santos ◽

Nilo Bazzoli ◽

Elizete Rizzo ◽

Gilmar Bastos Santos

Keyword(s):

Feeding Activity ◽

Gonadosomatic Index ◽

Secretory Activity ◽

Minas Gerais ◽

Reproductive Period ◽

Mature Stage ◽

Hepatosomatic Index ◽

Gonadal Maturation ◽

Caudal Region ◽

Iheringichthys Labrosus

The reproductive biology of Iheringichthys labrosus (Lütken, 1874) was studied in Furnas reservoir, Minas Gerais, Brazil. The fishes, 323 males and 817 females, were captured bimonthly from August 1993 to July 1994 by using gill nets with 3-10 cm mesh size. Gonadal maturation of the specimens was analyzed through macro and microscopical characteristics of the gonads. The secretory activity of the tubules of the caudal region of the testis was analyzed during the maturational testicular cycle. Females and males were in reproductive activity throughout the year in the reservoir. The peak of advanced maturation/mature stages occurred from October to January and of spawned/spent from February to May. The spawning of I. labrosus was identified as fractional or multiple type: occurring in the reservoir or in tributaries around it. The oocyte development of the species was asynchronous as different clusters of oocytes occurred simultaneously in the ovarian parenchyma. The epithelium of the tubules of the caudal region of the testis was in high secretory activity during advanced maturation/mature stage and this activity was absence in resting. The gonadosomatic index followed gonadal maturation, and the hepatosomatic index of females was lowest in advanced maturation/mature probably due the contribution of the liver in the vitellogenesis. The variations of the stomach repletion index, coelomic fat and condition factor indicated that the feeding activity was reduced and that the energetic reserves were consumed during the reproductive period.

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Nano-imaging trace elements at organelle levels in substantia nigra overexpressing α-synuclein to model Parkinson’s disease

Communications Biology ◽

10.1038/s42003-020-1084-0 ◽

2020 ◽

Vol 3 (1) ◽

Author(s):

Laurence Lemelle ◽

Alexandre Simionovici ◽

Philippe Colin ◽

Graham Knott ◽

Sylvain Bohic ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Substantia Nigra ◽

Trace Element ◽

Brain Diseases ◽

Transmission Electron ◽

Rough Endoplasmic Reticula ◽

Nano Imaging ◽

Cellular Compartments ◽

Endoplasmic Reticula

AbstractSub-cellular trace element quantifications of nano-heterogeneities in brain tissues offer unprecedented ways to explore at elemental level the interplay between cellular compartments in neurodegenerative pathologies. We designed a quasi-correlative method for analytical nanoimaging of the substantia nigra, based on transmission electron microscopy and synchrotron X-ray fluorescence. It combines ultrastructural identifications of cellular compartments and trace element nanoimaging near detection limits, for increased signal-to-noise ratios. Elemental composition of different organelles is compared to cytoplasmic and nuclear compartments in dopaminergic neurons of rat substantia nigra. They exhibit 150–460 ppm of Fe, with P/Zn/Fe-rich nucleoli in a P/S-depleted nuclear matrix and Ca-rich rough endoplasmic reticula. Cytoplasm analysis displays sub-micron Fe/S-rich granules, including lipofuscin. Following AAV-mediated overexpression of α-synuclein protein associated with Parkinson’s disease, these granules shift towards higher Fe concentrations. This effect advocates for metal (Fe) dyshomeostasis in discrete cytoplasmic regions, illustrating the use of this method to explore neuronal dysfunction in brain diseases.

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Structure of the Leydig Cell in the African Sideneck Turtle (Pelusios castaneus)

Sahel Journal of Veterinary Sciences ◽

10.54058/saheljvs.v17i2.103 ◽

2020 ◽

Vol 17 (2) ◽

pp. 19-25

Author(s):

S. G. Olukole ◽

B. O. Oke

Keyword(s):

Blood Vessels ◽

Leydig Cell ◽

Comparative Anatomy ◽

West African ◽

Freshwater Turtle ◽

Seminiferous Tubules ◽

Transmission Electron ◽

Entire Cell ◽

Rough Endoplasmic Reticula ◽

Endoplasmic Reticula

The African sideneck turtle (Pelusios castaneus) is a freshwater turtle of West African origin used in traditional medicine with little consumption as meat. There have been documentations on the reproductive biology of the turtle with no report on the structure of the Leydig cell of the animal. We described the structure of the Leydig cell of the adult African sideneck turtle using histology, microstereology and transmission electron microscopy. The Leydig cell of the African sideneck turtle were elliptical in shape when found proximal to blood vessels and elongated at other points within the testicular interstitium. Leydig cells occurred in cords or clusters of varying sizes and numbers (3-5 cells) that appear to be random in distribution possessing round to ovoid nuclei containing small amount of peripherally disposed heterochromatin with prominent nucleoli. The seminiferous tubules of the turtle occupied about 85% of the total testicular parenchyma while the interstitium occupied 15% of it. Of this 15%, the Leydig cell occupied about 10% while the stromal elements, inclusive of blood vessels occupied the remaining 5%. The cytoplasm of the Leydig cell was about 85% of the entire cell and comprised microfilaments, lipid droplets, smooth and rough endoplasmic reticula as well as numerous mitochondria. In conclusion, the histological and ultrastructural features of the Leydig cell of the African sideneck turtle bear close similarities with those of other reptiles with little variations. These variations include interstitial location as well as in relation to blood vessels within the testicular interstitium. Information made available by this study is expected to be useful in the comparative anatomy of the Leydig cell of turtles and reptiles.

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Ultrastructural changes accompany inhibition of proteoglycan synthesis in chondrocytes by Cyclofenil diphenol

Journal of Cell Science ◽

10.1242/jcs.92.2.271 ◽

1989 ◽

Vol 92 (2) ◽

pp. 271-280 ◽

Cited By ~ 1

Author(s):

C.A. Lancaster ◽

P.R. Fryer ◽

S. Griffiths ◽

R.M. Mason

Keyword(s):

Endoplasmic Reticulum ◽

Protein Synthesis ◽

Electron Density ◽

Lipid Droplets ◽

Secretory Pathway ◽

Ultrastructural Changes ◽

Proteoglycan Synthesis ◽

Filamentous Material

Cyclofenil diphenol, a weak non-steroidal oestrogen, profoundly inhibits [35S]proteoglycan synthesis in cultures of Swarm chondrosarcoma chondrocytes under conditions in which protein synthesis is only marginally reduced. In the present experiments it was shown that after a 40-min treatment with Cyclofenil diphenol (90 micrograms ml-1) most of the normally abundant Golgi stacks in these cells disappeared and after 60 min they were absent. After 2–3 h treatment the cisternae of the endoplasmic reticulum (ER) were grossly distended and transformed into large ribosome-studded vesicles containing flocculent and filamentous material. These changes were dependent on the concentration of Cyclofenil and were fully reversible within 21 h of withdrawing the drug. The ultrastructural changes differed in some aspects if protein synthesis was blocked with cycloheximide for 15 min or 180 min before and during treatment with Cyclofenil. The Golgi disappeared but the ER cisternae, though distended, formed a continuous network and swollen ribosome-studded vesicles did not develop. However, non-membrane-bounded structures containing lipid droplets and material of low electron density developed in the cytoplasm under these conditions. The ultrastructural changes induced by Cyclofenil differ from those induced by monensin and diethylcarbamazine, suggesting that the drug acts at a different point in the secretory pathway for macromolecules.

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Plasma levels of luteinizing hormone and gonadal maturation of lambari females under different photoperiods

Pesquisa Agropecuária Brasileira ◽

10.1590/s0100-204x2013000800036 ◽

2013 ◽

Vol 48 (8) ◽

pp. 1064-1070 ◽

Cited By ~ 1

Author(s):

Fernanda Keley Silva Pereira Navarro ◽

Rodrigo Diana Navarro ◽

Luis David Solis Murgas ◽

Marina Apocalypse Nogueira Pereira ◽

Guilherme Crispim Hundley

Keyword(s):

Luteinizing Hormone ◽

Plasma Levels ◽

Gonadosomatic Index ◽

Hepatosomatic Index ◽

Ovarian Maturation ◽

Gonadal Maturation ◽

Ovary Weight ◽

Randomized Design ◽

Final Weight ◽

Completely Randomized Design

The objective of this work was to evaluate the effect of photoperiod on luteinizing hormone (LH) plasma levels and gonadal maturation of lambari females. One hundred and twenty adult lambaris, distributed into 12 aquaria of 20 L each, were randomly subjected to three different treatments, in a completely randomized design, and four replicates. Treatments were photoperiods in hours of light (L) and darkness (D): T1, 0 L:24 D; T2, 12 L:12 D; T3, 24 L:0 D. After 40 days, fish were subjected to fasting for 24 hours and, then, anesthetized. Immediately after slaughter, fish were weighed, and their gonads and livers were removed and weighed. Ovaries were weighed and immersed in Bouin's fixative solution for 24 hours and, then, kept in 70% alcohol until processing the material. Subsequently, the oocyte developmental stage was determined. No significant differences were observed between treatments for final weight, ovary weight, gonadosomatic index (GSI), hepatosomatic index (HSI) and LH levels. In all treatments, lambari females showed maturing ovaries with prevalence of vitellogenic oocytes. Photoperiod does not affect the LH levels and ovarian maturation in lambari females.

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Ethylene-induced Rough Endoplasmic Reticula in Abscission Cells

PLANT PHYSIOLOGY ◽

10.1104/pp.47.1.162 ◽

1971 ◽

Vol 47 (1) ◽

pp. 162-163 ◽

Cited By ~ 17

Author(s):

Jack G. Valdovinos ◽

Thomas E. Jensen ◽

Linda M. Sicko

Keyword(s):

Rough Endoplasmic Reticula ◽

Endoplasmic Reticula

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Influence of 17β-oestradiol (E2) and 17α-hydroxyprogesterone (OHP) on ovarian maturation in Penaeus semisulcatus De Haan, 1844 (Decapoda, Dendrobranchiata, Penaeidae) from the Mediterranean Sea off Alexandria, Egypt

Crustaceana ◽

10.1163/15685403-bja10120 ◽

2021 ◽

Vol 94 (8) ◽

pp. 903-932

Author(s):

Ibrahim Gaber ◽

Oleg Latyshev

Keyword(s):

Mediterranean Sea ◽

Steroid Hormones ◽

Maximum Temperature ◽

Basal Cells ◽

Ovarian Maturation ◽

High Concentration ◽

Spawning Period ◽

Gonadal Maturation ◽

Penaeus Semisulcatus ◽

The Mediterranean

Abstract This study searches to provide appropriate conditions to trigger spawning in Penaeus semisulcatus in aquaculture. The aim was to test the effect of 17β-oestradiol and 17α-hydroxyprogesterone on ovarian maturation and to study the correlation between the different stages of ovarian maturation and hormonal levels in the ovaries, hepatopancreas, and haemolymph. Female shrimps were collected from Ras El-Tin beach and the fishing port to Abu Qir Bay of the Mediterranean Sea off Alexandria, Egypt from June 2018-August 2019. Shrimps were individually weighed and subsequently killed by thermal shock at a maximum temperature of 45°C. Gonadosomatic and hepatosomatic indices were calculated. The correlation between the gonadosomatic and hepatosomatic indices indicates the presence of endogenous and exogenous vitellogenesis. The haemolymph, hepatopancreas, and ovaries were studied by stereo- and electron microscopy. From 15 females in each season the mentioned tissues were isolated for the extraction and quantification of steroid hormones during the different stages of gonadal maturation using radioimmunoassay. An ecdysteroid- and steroid-extraction protocol was applied. Aliquots were collected from the haemolymph to identify 17β-oestradiol and 17α-hydroxyprogesterone by mass spectrometry. Five stages of gonadal maturation were observed. The hepatopancreas was formed by a set of tubules lined with pseudostratified epithelium composed of five cell types, cell E (undifferentiated), cell F (fibrillar), cell B (vesicular), R (reabsorbing), and M (basal) cells. Steroidogenic tissues were small in size and numerous. The ultrastructure of the ovary and hepatopancreas were studied during oocyte development. There was a high concentration of 17β-oestradiol and 17α-hydroxyprogesterone in stages I and II of ovarian maturation, coinciding with the preparation phase for vitellogenesis. A progressive decrease of these steroid hormones occurred during the course of gonadal maturation, and reached its lowest concentration in the spawning period. The ecdysone concentration did not fluctuate in ripe females. Its level increases from stages I-IV of vitellogenesis onward.

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