Ultrastructural changes, phenolics localization and heavy metals distribution in the leaf ofVaccinium myrtillusL. exposed to chromium in environment-preliminary observations

2003 ◽  
Vol 107 ◽  
pp. 181-184
Author(s):  
D. Bialonska ◽  
K. Sawicka-Kapusta ◽  
A. Obel ◽  
M. Kuras ◽  
T. Tykarska ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Ultrastructural Changes

scholarly journals Ultrastructural, Confocal and Viscoelastic Characteristics of Whole Blood and Plasma After Exposure to Cadmium and Chromium Alone and in Combination: An Ex Vivo Study

2017 ◽  
Vol 43 (3) ◽  
pp. 1288-1300 ◽  
Author(s):  
Chantelle Venter ◽  
Hester Magdalena Oberholzer ◽  
Janette Bester ◽  
Mia-Jeanne van Rooy ◽  
Megan Jean Bester
Keyword(s):  
Heavy Metals ◽  
Heavy Metal ◽  
Blood Coagulation ◽  
Ex Vivo ◽  
The Body ◽  
Laser Scanning Microscopy ◽  
Ultrastructural Changes ◽  
Target System ◽  
Metal Exposure ◽  
Confocal Laser

Background/Aims: Heavy metal pollution is increasing in the environment, contaminating water, food and air supplies. This can be linked to many anthropogenic activities. Heavy metals are absorbed through the skin, inhalation and/or orally. Irrespective of the manner of heavy metal entry in the body, the blood circulatory system is potentially the first to be affected following exposure and adverse effects on blood coagulation can lead to associated thrombotic disease. Although the plasma levels and the effects of cadmium (Cd) and chromium (Cr) on erythrocytes and lymphocytes have been described, the environmental exposure to heavy metals are not limited to a single metal and often involves metal mixtures, with each metal having different rates of absorption, different cellular, tissue, and organ targets. Therefore the aim of this study is to investigate the effects of the heavy metals Cd and Cr alone and whether Cr synergistically increases the effect of Cd on physiological important processes such as blood coagulation. Methods: Human blood was exposed to the heavy metals ex vivo, and thereafter morphological analysis was performed with scanning electron- and confocal laser scanning microscopy (CLSM) in conjunction with thromboelastography®. Results: The erythrocytes, platelets and fibrin networks presented with ultrastructural changes, including varied erythrocytes morphologies, activated platelets and significantly thicker fibrin fibres in the metal-exposed groups. CLSM analysis revealed the presence of phosphatidylserine on the outer surface of the membranes of the spherocytic erythrocytes exposed to Cd and Cr alone and in combination. The viscoelastic analysis revealed only a trend that indicates that clots that will form after heavy metal exposure, will likely be fragile and unstable especially for Cd and Cr in combination. Conclusion: This study identified the blood as an important target system of Cd and Cr toxicity.

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

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.

Whole blood ultrastructural alterations by mercury, nickel and manganese alone and in combination: An ex vivo investigation

2020 ◽  
pp. 074823372098311
Author(s):  
PB Maseko ◽  
M van Rooy ◽  
H Taute ◽  
C Venter ◽  
JC Serem ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Confocal Laser Scanning Microscopy ◽  
Laser Scanning ◽  
Ex Vivo ◽  
Laser Scanning Microscopy ◽  
Confocal Laser Scanning ◽  
Scanning Microscopy ◽  
Coagulation System ◽  
Ultrastructural Changes ◽  
Confocal Laser

The distribution of metals across the environment is increasingly becoming a major concern as they not only pollute the environment but also pose a danger to humans and animals. Human exposure to heavy metals often occurs as a combination of metals the synergistic effects of which can be more toxic than a single metal. The aim of this study was to investigate the effects that the metals mercury (Hg), nickel (Ni) and manganese (Mn) alone and in combination have on erythrocyte morphology and other components of the coagulation system using the haemolysis assay, scanning electron microscopy (SEM), and confocal laser scanning microscopy. Human blood was exposed to the heavy metals ex vivo, and percentage haemolysis was determined. Ultrastructural analysis of erythrocytes, platelets and fibrin networks was performed using SEM. Analysis of phosphatidylserine (PS) flip-flop was determined using confocal laser scanning microscopy. At the highest concentration of 10,000× the World Health Organization safety limit, all the metals caused haemolysis. The results showed that the exposure of erythrocytes to Hg alone and in combination with other metals displayed more haemolysis compared to Ni and Mn alone and in combination. Components of the coagulation system showed ultrastructural changes, including the formation of echinocytes and the activation of platelets with all single metals as well as the combinations. Confocal laser scanning microscopy analysis showed the presence of PS on the outer surface of the echinocytes that were exposed to metals alone and in combination. It can, therefore, be concluded that these heavy metals have a negative impact on erythrocytes and the coagulation system.

scholarly journals Using extracellular polymeric substances (EPS)-producing cyanobacteria for the bioremediation of heavy metals: do cations compete for the EPS functional groups and also accumulate inside the cell?

Microbiology ◽  
2011 ◽  
Vol 157 (2) ◽  
pp. 451-458 ◽  
Author(s):  
Sara Pereira ◽  
Ernesto Micheletti ◽  
Andrea Zille ◽  
Arlete Santos ◽  
Pedro Moradas-Ferreira ◽  
...  
Keyword(s):  
Heavy Metals ◽  
Extracellular Polymeric Substances ◽  
Metal Removal ◽  
Ultrastructural Changes ◽  
Wild Type ◽  
Mutual Inhibition ◽  
Biotechnological Potential ◽  
Surrounding Environment ◽  
In The Wild ◽  
Mutant Cells

Many cyanobacteria produce extracellular polymeric substances (EPS) mainly of polysaccharidic nature. These EPS can remain associated to the cell surface as sheaths, capsules and/or slimes, or be liberated into the surrounding environment as released polysaccharides (RPS). The ability of EPS-producing cyanobacteria to remove heavy metals from aqueous solutions has been widely reported in the literature, focusing mainly on the biotechnological potential. However, the knowledge of the effects of the metals in the cell's survival/growth is still scarce, particularly when they are simultaneously exposed to more than one metal. This work evaluated the effects of different concentrations of Cu2+ and/or Pb2+ in the growth/survival of Gloeothece sp. PCC 6909 and its sheathless mutant Gloeothece sp. CCY 9612. The results obtained clearly showed that both phenotypes are more severely affected by Cu2+ than Pb2+, and that the mutant is more sensitive to the former metal than the wild-type. Evident ultrastructural changes were also observed in the wild-type and mutant cells exposed to high levels (10 mg l−1) of Cu2+. Moreover, in bi-metal systems, Pb2+ was preferentially removed compared with Cu2+, being the RPS of the mutant that is the most efficient polysaccharide fraction in metal removal. In these systems, the simultaneous presence of Cu2+ and Pb2+ caused a mutual inhibition in the adsorption of each metal.

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

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.

Basal Lamina Formation in DMBA Induced Mammary Carcinoma

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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