Histological, Histochemical and Ultrastructural Changes in the Digestive Tract of Sturgeon Acipenser naccarii During Early Ontogeny

The deleterious effects of agricultural insecticides on non-target organisms have been under investigation for a number of years. Most studies have dealt with the degree of toxicity, mechanism of action, metabolism, or distribution in the biosphere. There has been comparatively little interest in morphological effects of an insecticide at its site of entry. Toxaphene, a general-purpose organochlorine insecticide that is widely and heavily applied in the U.S. is quite toxic to fish. It can be absorbed via the gills or the gut. This study examined the effects of Toxaphene on the absorptive cells of the anterior intestinal bulb in goldfish (Carassius auratus). These cells are involved in the uptake of dietary lipids; since Toxaphene is lipid-soluble, this was considered the likeliest region of the digestive tract to exhibit damage due to its presence.

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Ultrastructural Changes of the Digestive Tract of Pomacea canaliculata Exposed to Copper at Lethal Concentration

Sains Malaysiana ◽

10.17576/jsm-2021-5010-02 ◽

2021 ◽

Vol 50 (10) ◽

pp. 2869-2876

Author(s):

Vipawee Dummee ◽

Maleeya Kruatrachue ◽

Sombat Singhakaew ◽

Phanwimol Tanhan

Keyword(s):

Heavy Metals ◽

Digestive Tract ◽

Lethal Concentration ◽

Ultrastructural Changes ◽

Pomacea Canaliculata ◽

Freshwater Environment ◽

Cu Contamination ◽

Cu Pollution ◽

Freshwater Environments ◽

Membrane Destabilization

The present study was undertaken to elucidate the basis of cellular reactions and to verify the suitability of Pomacea canaliculata digestive tract ultrastructure as a biomarker for assessing the Cu pollution in freshwater environments. Two-month-old P. canaliculata were exposed to 96-h lethal concentration of Cu (0.15 mg L-1) for 96 h. Electron microscope investigations showed different alterations of organelles in the epithelial cells lining the esophagus and intestine. The most striking changes were damages to the mitochondria, RER, and nucleus typified by loss of cristae and degeneration of mitochondria; degranulation and fragmentation of RER. In nucleus, karyolysis and rupture of nuclear envelope were observed. These changes were attributed to membrane destabilization and increased membrane permeability to ions under the influence of toxicants or heavy metals. These findings indicate the possibility of using the P. canaliculata as biomonitor for Cu contamination in the freshwater environment.

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Embryology and early ontogeny of an anemonefish Amphiprion ocellaris

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315407054227 ◽

2007 ◽

Vol 87 (4) ◽

pp. 1025-1033 ◽

Cited By ~ 13

Author(s):

Inayah Yasir ◽

Jian G. Qin

Keyword(s):

Coral Reef ◽

Embryonic Development ◽

Digestive Tract ◽

Coral Reef Fish ◽

Ventral Surface ◽

Early Ontogeny ◽

Egg Activation ◽

Pectoral Fins ◽

Vegetal Pole ◽

Blood Formation

The present study describes the embryonic development and early ontogeny of Amphiprion ocellaris from fertilization to post hatching. Anemonefish spontaneously spawned at 27–28°C. The newly laid eggs were orange in colour and elliptical in shape (1.8×0.8 mm). Melanin appeared as a black mass situated at the vegetal pole in mature eggs. This is rarely seen in eggs of other fish species. We documented developmental times at 27–28°C to egg activation (0.5 h), cleavage (4 h), blastula (11.5 h), gastrula (20 h), neurula (24.5 h), somite (28.5 h), turnover (72 h), blood formation (113 h) and internal ear and jaw formation (144 h). Hatching occurred 152 h after fertilization. On day 4, the eye buds were pigmented and melanophores formed on the ventral surface of the embryo. Internal ear and gill formation were completed on day 5 and coincided with movement of the opercula and pectoral fins. The mouth formed on day 6 and the digestive tract appeared on day 7. By day 10, the yolk was fully absorbed and a substantial amount of food was observed in the gut. Dark and orange pigments were dispersed and aggregated through muscle contractions by day 14, but red pigments did not appear until the fish were three months old. This study contributes to a further understanding of the embryology and the early ontogeny of damselfish and may help improve the culture of coral reef fish.

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Development of digestive tract and enzyme activities during the early ontogeny of the tropical gar Atractosteus tropicus

Fish Physiology and Biochemistry ◽

10.1007/s10695-015-0070-9 ◽

2015 ◽

Vol 41 (5) ◽

pp. 1075-1091 ◽

Cited By ~ 14

Author(s):

C. A. Frías-Quintana ◽

G. Márquez-Couturier ◽

C. A. Alvarez-González ◽

D. Tovar-Ramírez ◽

H. Nolasco-Soria ◽

...

Keyword(s):

Digestive Tract ◽

Enzyme Activities ◽

Early Ontogeny ◽

Tropical Gar ◽

Atractosteus Tropicus

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Fine Structural Changes in the Microvasculature of the Mouse Pinna: Aging and Radiation Injury

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100050287 ◽

1974 ◽

Vol 32 ◽

pp. 54-55

Author(s):

S. Phyllis Steamer ◽

Rosemarie L. Devine

Keyword(s):

Structural Changes ◽

Radiation Treatment ◽

Arterial Stenosis ◽

Ultrastructural Changes ◽

Vascular Effects ◽

Microvascular Changes ◽

Surrounding Connective Tissue ◽

Fission Neutrons ◽

Total Body

The importance of radiation damage to the skin and its vasculature was recognized by the early radiologists. In more recent studies, vascular effects were shown to involve the endothelium as well as the surrounding connective tissue. Microvascular changes in the mouse pinna were studied in vivo and recorded photographically over a period of 12-18 months. Radiation treatment at 110 days of age was total body exposure to either 240 rad fission neutrons or 855 rad 60Co gamma rays. After in vivo observations in control and irradiated mice, animals were sacrificed for examination of changes in vascular fine structure. Vessels were selected from regions of specific interest that had been identified on photomicrographs. Prominent ultrastructural changes can be attributed to aging as well as to radiation treatment. Of principal concern were determinations of ultrastructural changes associated with venous dilatations, segmental arterial stenosis and tortuosities of both veins and arteries, effects that had been identified on the basis of light microscopic observations. Tortuosities and irregularly dilated vein segments were related to both aging and radiation changes but arterial stenosis was observed only in irradiated animals.

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Basal Lamina Formation in DMBA Induced Mammary Carcinoma

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100080109 ◽

1977 ◽

Vol 35 ◽

pp. 534-535

Author(s):

I. Russo ◽

J. Saby ◽

J. Russo

Keyword(s):

Mammary Carcinoma ◽

Virgin Female ◽

Mammary Glands ◽

Sesame Oil ◽

Female Rats ◽

Ultrastructural Changes ◽

Post Inoculation ◽

Intermediate Type ◽

Sprague Dawley ◽

Intercellular Spaces

It has been previously demonstrated that DMBA-induced rat mammary carcinoma originates in the terminal end bud (TEB) of the mammary gland by proliferation of intermediate type cells (1). The earliest lesion identified is the intraductal proliferation (IDP), which gives rise to intraductal carcinomas. These evolve to cribriform, papillary and comedo types (2). In the present work, we report the ultrastructural changes that take place in the IDP for the formation of a cribriform pattern.Fifty-five-day-old Sprague Dawley virgin female rats were inoculated intra- gastrically with 20 mg 7,12-dimethylbenz(a)anthracene (DMBA) in 1 ml sesame oil. Non-inoculated, age-matched females were used as controls. Mammary glands from both control and experimental rats were removed weekly from the time of inoculation until 86 days post-inoculation. The glands were fixed and processed for electron microscopy (2).The first change observed in IDP's was the widening of intercellular spaces and the secretion of an electron dense material into these spaces (Fig. 1).

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Ultrastructural Changes of the Symbiotic Chlorella-Like Alga Isolated from Hydra Viridis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100054212 ◽

1982 ◽

Vol 40 ◽

pp. 320-321

Author(s):

K.W. Lee ◽

R.H. Meints ◽

D. Kuczmarski ◽

J.L. Van Etten

Keyword(s):

Time Course ◽

Reciprocal Cross ◽

Ultrastructural Level ◽

Ultrastructural Changes ◽

Symbiotic Relationship ◽

Cell Recognition ◽

Green Hydra ◽

Different Strains ◽

Hydra Viridis

The physiological, biochemical, and ultrastructural aspects of the symbiotic relationship between the Chlorella-like algae and the hydra have been intensively investigated. Reciprocal cross-transfer of the Chlorellalike algae between different strains of green hydra provide a system for the study of cell recognition. However, our attempts to culture the algae free of the host hydra of the Florida strain, Hydra viridis, have been consistently unsuccessful. We were, therefore, prompted to examine the isolated algae at the ultrastructural level on a time course.

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Ultrastructural Changes in Patients With Heat Stroke

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068047 ◽

1970 ◽

Vol 28 ◽

pp. 210-211

Author(s):

O. T. Minick ◽

M. C. Kew

Keyword(s):

Liver Damage ◽

Heat Stroke ◽

Free State ◽

Ultrastructural Changes ◽

Gold Mines

The effects of heat stroke on hepatic structure were studied in 32 Bantu patients who worked underground in the Transvaal and Orange Free State Gold Mines.Judging from biochemical and morphologic findings, liver damage is an invariable complication of heat stroke. In the milder cases (90 per cent) raised enzyme levels, bromsulphalein retention, and increased prothrombin times were the most common abnormalities.

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Fine Structural Alterations in Thyroid Follicular Cells (FC) and Changes in Serum Thyroxine Produced by Feeding Polychlorinated Biphenyl (PCB) to Rats

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079929 ◽

1977 ◽

Vol 35 ◽

pp. 498-499

Author(s):

W.T. Collins ◽

Charles C. Capen ◽

Louis Kasza

Keyword(s):

Feed Efficiency ◽

Polychlorinated Biphenyl ◽

Serum Proteins ◽

Skin Lesions ◽

Hepatic Necrosis ◽

Ultrastructural Changes ◽

Lymphoid Tissues ◽

Heat Transfer Fluids ◽

Thyroid Follicular Cells ◽

Peripheral Metabolism

The widespread contamination of the environment with PCB, a compound used extensively by industry in hydraulic and heat transfer fluids as well as plasticizers and solvents in adhesives and sealants, has resulted in detectable tissue levels in a large portion of the human population, domestic animals, and wildlife. Intoxication with PCB produces severe hepatic necrosis, degeneration of lymphoid tissues and kidney, skin lesions, decreased reproductive performance, reduced feed efficiency, and decreased weight gain. PCB also has been reported to reduce the binding of thyroid hormone to serum proteins and enhance the peripheral metabolism of thyroxine with increased excretion of thyroxine-glucuronide in the bile (Bastomsky, Endocrinology 95: 1150-1155, 1974).The objectives of this investigation were (1) to investigate the histopathologic, histochemical, and ultrastructural changes in thyroid FC produced by the acute (4 week) and chronic (12 week) administration of low (50 ppm) and high (500 ppm) doses of PCB to rats, (2) to correlate these alterations to changes in serum immunoreactive thyroxine concentration, and (3) to investigate the persistence of the effects of PCB on the thyroid gland.

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