Ultrastructural changes in Tritrichomonas foetus after treatments with AlPcS4 and photodynamic therapy

Programmed cell death in T. foetus does not seem to make sense at first sight; however, different mechanisms of cellular death in this unicellular organism have been observed. This review summarizes the available data related to programmed cell death already published for the cattle parasite T. foetus and attempts to clarify some crucial points to understand this mechanism found in non-mitochondriates parasites, as well as assist in future research. Important results with different treatments showed that the T. foetus can choose among different pathways how to initiate cell death. Thus, a major challenge for cellular death research remains the identification of the molecular cell death machinery of this protist, such as caspases pathway, nuclear abnormalities, morphology cell changes, cellular death in this parasite and the prospects in the future research. Although, the possibility of the existence of different pathways to cell death in trichomonads is discussed and a model for possible executioners pathways during T. foetus cell death is proposed.

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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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