Ultrastructure of the effect of T-514 obtained from Karwinskia humboldtiana on assembly and integrity of yeast's peroxisomes

Karwinskia humboldtiana is a poisonous plant that grows in semi desertic areas in north and central México. It produces several substances with different toxic effects. One of them designated T-514 damages severely the lung, kidney and liver, producing in the hepatoeyte large intracellular fat deposits and necrosis. Preliminary observations demonstrated that three is a decrease in the amount of peroxisomes in the hepatocytes of experimentally intoxicated rats and monkeys. To study the effect exerted by the T-514 on peroxisomes, a yeast model was selected, thus, three species: Saccha romices cerevisiae, Ilansenula polymorpha and Candida boidinii were used, because there is information concerning their peroxisome's morphology, enzyme content, biological behaviour under different culture conditions and biogenesis.

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The Toxic Effects of Lindane On Microcystis Aeruginosa And The Influence of pH And DOM Dependent Effects of Lindane On Microcystis Aeruginosa

10.21203/rs.3.rs-795222/v1 ◽

2021 ◽

Author(s):

Deng Xiru ◽

Jiang Yingnan ◽

Xian Qiming

Keyword(s):

Microcystis Aeruginosa ◽

Total Protein ◽

Culture Conditions ◽

Toxic Effects ◽

Maximal Effect ◽

Sod Activity ◽

Protein Levels ◽

Toxicant Concentration ◽

Effect Concentration ◽

Influence Of Ph

Abstract The toxic effects of Lindane (γ-BHC) on Microcystis aeruginosa were studied under lab culture conditions. Total protein levels, as well as malondialdehyde (MDA) levels and superoxide dismutase (SOD) enzyme activity, in algal cells, were determined after exposure to different concentrations of Lindane. The bioaccumulation of Lindane, as well as the influence of pH and dissolved organic matter (DOM), on the toxic effects was also evaluated in algal cells. The growth of M. aeruginosa was inhibited by Lindane treatment (96 h), resulting in 50% of maximal effect (EC50) concentration of 442 μg/L. In addition the lowest observed effect concentration (LOEC) was found to be 120 μg/L, the no observed effect concentration (NOEC) 60 μg/L, and the maximum acceptable toxicant concentration (MATC) 85 μg/L. With increasing concentrations of Lindane and exposure time, M. aeruginosa growth was significantly inhibited; in addition, total protein levels and SOD activity significantly decreased. MDA concentration, however, showed an insignificant increase after 96 h. Lindane has the potential for bioaccumulation in algal cells with a bioconcentration factor (BCF) of 340. Furthermore, the toxic effects of Lindane on M. aeruginosa were influenced by environmental factors, such as pH and DOM. The toxic effects decreased with increasing pH and humic acid concentrations. Ultrastructure cell images were used to depict Lindane induced apoptosis.

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Mammalian ribosomal and chaperone protein RPS3A counteracts α-synuclein aggregation and toxicity in a yeast model system

Biochemical Journal ◽

10.1042/bj20130417 ◽

2013 ◽

Vol 455 (3) ◽

pp. 295-306 ◽

Cited By ~ 8

Author(s):

Stijn De Graeve ◽

Sarah Marinelli ◽

Frank Stolz ◽

Jelle Hendrix ◽

Jurgen Vandamme ◽

...

Keyword(s):

Parkinson’S Disease ◽

Parkinson's Disease ◽

Model System ◽

Toxic Effects ◽

Screening System ◽

Brain Protein ◽

Chaperone Protein ◽

Main Protein ◽

Yeast Model

A yeast screening system was developed and successfully used to isolate a brain protein that counteracts the toxic effects of the main protein involved in Parkinson's disease.

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Some Conditions Necessary for Pinocytosis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100100457 ◽

1968 ◽

Vol 26 ◽

pp. 142-143

Author(s):

M. W. Brightman

Keyword(s):

Smooth Muscle ◽

Cell Membrane ◽

Toxic Effects ◽

Cytological Evidence ◽

Cell Processes

The cytological evidence for pinocytosis is the focal infolding of the cell membrane to form surface pits that eventually pinch off and move into the cytoplasm. This activity, which can be inhibited by oxidative and glycolytic poisons, is performed only by cell processes that are at least 300A wide. However, the interpretation of such toxic effects becomes equivocal if the membrane invaginations do not normally lead to the formation of migratory vesicles, as in some endothelia and in smooth muscle. The present study is an attempt to set forth some conditions under which pinocytosis, as distinct from the mere inclusion of material in surface invaginations, can take place.

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Scanning Microscopy of Human Intestinal Explants in Organ Culture

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100095248 ◽

1972 ◽

Vol 30 ◽

pp. 396-397

Author(s):

Bruce Wetzel ◽

Robert Buscho ◽

Raphael Dolin

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Culture Conditions ◽

Human Fetuses ◽

Enteric Disease ◽

Organ Cultures ◽

Growth Of A Variety ◽

Normal Human ◽

Fetal Intestine ◽

Scanning Electron

It has been reported that explants of human fetal intestine can be maintained in culture for up to 21 days in a viable condition and that these organ cultures support the growth of a variety of known viral agents responsible for enteric disease. Scanning electron microscopy (SEM) has been undertaken on several series of these explants to determine their appearance under routine culture conditions.Fresh specimens of jejunum obtained from normal human fetuses were washed, dissected into l-4mm pieces, and cultured in modified Leibowitz L-15 medium at 34° C as previously described. Serial specimens were fixed each day in 3% glutaraldehyde for 90 minutes at room temperature, rinsed, dehydrated, and dried by the CO2 critical point method in a Denton DCP-1 device. Specimens were attached to aluminum stubs with 3M transfer tape No. 465, and one sample on each stub was carefully rolled along the adhesive such that villi were broken off to expose their interiors.

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Lectin Binding Studies on RNA Tumor Virus-Infected Cells

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100115250 ◽

1975 ◽

Vol 33 ◽

pp. 326-327

Author(s):

D. C. Hixson

Keyword(s):

Binding Sites ◽

Lectin Binding ◽

Culture Conditions ◽

3T3 Cells ◽

Binding Studies ◽

Con A ◽

Microscopic Studies ◽

Tumor Virus ◽

Infected Cells ◽

Cell Culture Conditions

The abilities of plant lectins to preferentially agglutinate malignant cells and to bind to specific monosaccharide or oligosaccharide sequences of glycoproteins and glycolipids make them a new and important biochemical probe for investigating alterations in plasma membrane structure which may result from malignant transformation. Electron and light microscopic studies have demonstrated clustered binding sites on surfaces of SV40-infected or tryp- sinized 3T3 cells when labeled with concanavalin A (con A). No clustering of con A binding sites was observed in normal 3T3 cells. It has been proposed that topological rearrangement of lectin binding sites into clusters enables con A to agglutinate SV40-infected or trypsinized 3T3 cells (1). However, observations by other investigators have not been consistent with this proposal (2) perhaps due to differences in reagents used, cell culture conditions, or labeling techniques. The present work was undertaken to study the lectin binding properties of normal and RNA tumor virus-infected cells and their associated viruses using lectins and ferritin-conjugated lectins of five different specificities.

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Neutrophil migration through in vitro interstitial matrix

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124872 ◽

1992 ◽

Vol 50 (1) ◽

pp. 894-895

Author(s):

J. Roemer ◽

S.R. Simon

Keyword(s):

Extracellular Matrix ◽

Smooth Muscle ◽

Cell Migration ◽

Smooth Muscle Cells ◽

Inflammatory Cell ◽

Neutrophil Migration ◽

Culture Conditions ◽

Aortic Smooth Muscle ◽

Specific Culture

We are developing an in vitro interstitial extracellular matrix (ECM) system for study of inflammatory cell migration. Falcon brand Cyclopore membrane inserts of various pore sizes are used as a support substrate for production of ECM by R22 rat aortic smooth muscle cells. Under specific culture conditions these cells produce a highly insoluble matrix consisting of typical interstitial ECM components, i.e.: types I and III collagen, elastin, proteoglycans and fibronectin.

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Ultrastructural features of prognostic significance in human oral cancer

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100123490 ◽

1992 ◽

Vol 50 (1) ◽

pp. 618-619

Author(s):

Karvita B. Ahluwalia ◽

Nidhi Sharma

Keyword(s):

Oral Cancer ◽

Squamous Cell ◽

Common Knowledge ◽

Prognostic Significance ◽

Growth Control ◽

Terminal Differentiation ◽

Squamous Cell Carcinomas ◽

Effective Therapy ◽

Invasive Potential ◽

Biological Behaviour

It is common knowledge that apparently similar tumors often show different responses to therapy. This experience has generated the idea that histologically similar tumors could have biologically distinct behaviour. The development of effective therapy therefore, has the explicit challenge of understanding biological behaviour of a tumor. The question is which parameters in a tumor could relate to its biological behaviour ? It is now recognised that the development of malignancy requires an alteration in the program of terminal differentiation in addition to aberrant growth control. In this study therefore, ultrastructural markers that relate to defective terminal differentiation and possibly invasive potential of cells have been identified in human oral leukoplakias, erythroleukoplakias and squamous cell carcinomas of the tongue.

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Ultrastructural Study of a differentiating human colon carcinoma cell line

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100158583 ◽

1990 ◽

Vol 48 (3) ◽

pp. 208-209

Author(s):

Sylvie Polak-Charcon ◽

Mehrdad Hekmati ◽

Yehuda Ben Shaul

Keyword(s):

Cell Line ◽

Morphological Changes ◽

Secretory Granules ◽

Human Colon ◽

Cell Types ◽

Culture Conditions ◽

Morphological Evidence ◽

Human Colon Carcinoma Cell ◽

Colon Cell

The epithelium of normal human colon mucosa “in vivo” exhibits a gradual pattern of differentiation as undifferentiated stem cells from the base of the crypt of “lieberkuhn” rapidly divide, differentiate and migrate toward the free surface. The major differentiated cell type of the intestine observed are: absorptive cells displaying brush border, goblet cells containing mucous granules, Paneth and endocrine cells containing dense secretory granules. These different cell types are also found in the intestine of the 13-14 week old embryo.We present here morphological evidence showing that HT29, an adenocarcinoma of the human colon cell line, can differentiate into various cell types by changing the growth and culture conditions and mimic morphological changes found during development of the intestine in the human embryo.HT29 cells grown in tissue-culture dishes in DMEM and 10% FCS form at late confluence a multilayer of morphologically undifferentiated cell culture covered with irregular microvilli, and devoid of tight junctions (Figs 1-3).

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