Algicidal properties of the pesticide cosolvent Aerotex 3470: growth, ATP synthesis, and ultrastructure

The algicidal properties of Aerotex 3470, a pesticide cosolvent in several fenitrothion formulations, have been investigated under controlled laboratory conditions. Aerotex (1–100 ppm) inhibited the growth of three unicellular freshwater algae (Chlamydomonas reinhardii, Chlorella pyrenoidosa, and Scenedesmus obtusiusculus) on agar plates and in liquid culture. Prolongation of the lag phase was directly related to Aerotex concentration. Algal cultures exposed for 1 h to Aerotex (1–10 ppm) had significantly reduced ATP levels. In all cases (agar, liquid culture, and ATP bioassays), Chlamydomonas and Chlorella were more sensitive to Aerotex than Scenedesmus.Electron microscopy demonstrated gross ultrastructural changes in Chlamydomonas treated for 1 h with Aerotex (5 ppm), including swollen mitochondria, disorganization of thylakoids, and crenulation of the cell membrane. Similar membrane damage was caused by 1-methylnaphthalene (5 ppm), a constituent of Aerotex.

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Toxic effect of puromycin on erythrocyte membranes which is unrelated to inhibition of protein synthesis

Blood ◽

10.1182/blood.v45.1.21.21 ◽

1975 ◽

Vol 45 (1) ◽

pp. 21-27 ◽

Cited By ~ 3

Author(s):

ER Burka ◽

SK Ballas ◽

SM Sabesin

Keyword(s):

Protein Synthesis ◽

Cell Membrane ◽

Toxic Effect ◽

Erythrocyte Membrane ◽

Membrane Damage ◽

Erythrocyte Membranes ◽

Erythroid Cell ◽

Ultrastructural Changes ◽

Direct Toxic Effect ◽

Increased Susceptibility

Abstract Exposure of rabbit or human erythrocytes to concentrations of puromycin as low as 7 x 10(-4)M for 2 hr causes damage to the cell membrane, as evidenced by increased susceptibility of the cells to hyposmotic lysis, increased cell rigidity, and ultrastructural changes consistent with severe membrane damage. Puromycin causes a concentration-dependent internalization of the erythrocyte membrane, resulting in vacuolization of the cells, at concentrations between 7 x 10(-4) M and 10(-2) M. Since the erythrocyte does not synthesize protein, the data indicate that puromycin has a direct toxic effect on erythroid cell membranes which is unrelated to its action in inhibiting the synthesis of protein.

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Toxic effect of puromycin on erythrocyte membranes which is unrelated to inhibition of protein synthesis

Blood ◽

10.1182/blood.v45.1.21.bloodjournal45121 ◽

1975 ◽

Vol 45 (1) ◽

pp. 21-27

Author(s):

ER Burka ◽

SK Ballas ◽

SM Sabesin

Keyword(s):

Protein Synthesis ◽

Cell Membrane ◽

Toxic Effect ◽

Erythrocyte Membrane ◽

Membrane Damage ◽

Erythrocyte Membranes ◽

Erythroid Cell ◽

Ultrastructural Changes ◽

Direct Toxic Effect ◽

Increased Susceptibility

Exposure of rabbit or human erythrocytes to concentrations of puromycin as low as 7 x 10(-4)M for 2 hr causes damage to the cell membrane, as evidenced by increased susceptibility of the cells to hyposmotic lysis, increased cell rigidity, and ultrastructural changes consistent with severe membrane damage. Puromycin causes a concentration-dependent internalization of the erythrocyte membrane, resulting in vacuolization of the cells, at concentrations between 7 x 10(-4) M and 10(-2) M. Since the erythrocyte does not synthesize protein, the data indicate that puromycin has a direct toxic effect on erythroid cell membranes which is unrelated to its action in inhibiting the synthesis of protein.

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The effect of two organophosphate insecticides on the growth of freshwater algae

Canadian Journal of Botany ◽

10.1139/b77-170 ◽

1977 ◽

Vol 55 (11) ◽

pp. 1453-1456 ◽

Cited By ~ 16

Author(s):

Brendan C. Birmingham ◽

Brian Colman

Keyword(s):

Growth Rate ◽

Green Alga ◽

Growth Stimulation ◽

Chlorella Pyrenoidosa ◽

Freshwater Algae ◽

Chlamydomonas Reinhardii ◽

Blue Green Algae ◽

Algal Groups ◽

Green Alga Chlorella ◽

Similar Growth

Seven freshwater algae were grown in the presence of Abate® 4-E (O,O,O′,O′-tetramethyl-O,O′-thiodi-p-phenylene phosphorothioate) and Dursban® M-3633 (O,O-diethyl-O-(3,5,6-trichloro-2-pyridyl) phosphorothioate) at 1,10, and 100 μg/ℓ active ingredient. The response of different algal groups to the insecticides was highly variable.The growth rate of the nitrogen-fixing blue-green alga Anabaena flos-aquae was increased from 22% at 10 μg/ℓ Abate to 58% at 100 μg/ℓ Abate when grown on nitrogen-free medium. Dursban caused similar growth stimulation. The green alga Chlamydomonas reinhardii showed growth stimulation in response to 100 μg/ℓ Dursban.Significant decreases in growth rate were observed for the green alga Chlorella pyrenoidosa after treatment with 10 μg/ℓ Abate (8%) and 100 μg/ℓ Dursban (12%). The diatom Navicula pelliculosa gave decreases in growth rate of the same order with 10 μg/ℓ Abate or Dursban.No significant effect on the growth rates of the diatom Navicula minima or the blue-green algae Coccochloris peniocystis, Oscillatoria sp., and Anabaena flos-aquae grown in the presence of nitrate was detected after treatment with either insecticide.

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Effects of the cationic protein poly-L-arginine on airway epithelial cellsin vitro

Mediators of Inflammation ◽

10.1080/09622935020138172 ◽

2002 ◽

Vol 11 (3) ◽

pp. 141-148 ◽

Cited By ~ 27

Author(s):

Shahida Shahana ◽

Caroline Kampf ◽

Godfried M. Roomans

Keyword(s):

Electron Microscopy ◽

Epithelial Cells ◽

Cell Membrane ◽

Cell Damage ◽

Membrane Damage ◽

Light And Electron Microscopy ◽

Airway Epithelial Cells ◽

Airway Epithelial ◽

Cationic Protein ◽

Induced Apoptosis

Background: Allergic asthma is associated with an increased number of eosinophils in the airway wall. Eosinophils secrete cationic proteins, particularly major basic protein (MBP).Aim: To investigate the effect of synthetic cationic polypeptides such as poly-L-arginine, which can mimic the effect of MBP, on airway epithelial cells.Methods: Cultured airway epithelial cells were exposed to poly-L-arginine, and effects were determined by light and electron microscopy.Results: Poly-L-arginine induced apoptosis and necrosis. Transmission electron microscopy showed mitochondrial damage and changes in the nucleus. The tight junctions were damaged, as evidenced by penetration of lanthanum. Scanning electron microscopy showed a damaged cell membrane with many pores. Microanalysis showed a significant decrease in the cellular content of magnesium, phosphorus, sodium, potassium and chlorine, and an increase in calcium. Plakoglobin immunoreactivity in the cell membrane was decreased, indicating a decrease in the number of desmosomes.Conclusions: The results point to poly-L-arginine induced membrane damage, resulting in increased permeability, loss of cell-cell contacts and generalized cell damage.

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Reduced Graphene Oxides Modulate the Expression of Cell Receptors and Voltage-Dependent Ion Channel Genes of Glioblastoma Multiforme

International Journal of Molecular Sciences ◽

10.3390/ijms22020515 ◽

2021 ◽

Vol 22 (2) ◽

pp. 515

Author(s):

Jaroslaw Szczepaniak ◽

Joanna Jagiello ◽

Mateusz Wierzbicki ◽

Dorota Nowak ◽

Anna Sobczyk-Guzenda ◽

...

Keyword(s):

Glioblastoma Multiforme ◽

Cell Membrane ◽

Ion Channel ◽

Functional Groups ◽

Membrane Damage ◽

Infrared Analysis ◽

Graphene Oxides ◽

Antitumor Effects ◽

Reduced Graphene ◽

Voltage Dependent

The development of nanotechnology based on graphene and its derivatives has aroused great scientific interest because of their unusual properties. Graphene (GN) and its derivatives, such as reduced graphene oxide (rGO), exhibit antitumor effects on glioblastoma multiforme (GBM) cells in vitro. The antitumor activity of rGO with different contents of oxygen-containing functional groups and GN was compared. Using FTIR (fourier transform infrared) analysis, the content of individual functional groups (GN/exfoliation (ExF), rGO/thermal (Term), rGO/ammonium thiosulphate (ATS), and rGO/ thiourea dioxide (TUD)) was determined. Cell membrane damage, as well as changes in the cell membrane potential, was analyzed. Additionally, the gene expression of voltage-dependent ion channels (clcn3, clcn6, cacna1b, cacna1d, nalcn, kcne4, kcnj10, and kcnb1) and extracellular receptors was determined. A reduction in the potential of the U87 glioma cell membrane was observed after treatment with rGO/ATS and rGO/TUD flakes. Moreover, it was also demonstrated that major changes in the expression of voltage-dependent ion channel genes were observed in clcn3, nalcn, and kcne4 after treatment with rGO/ATS and rGO/TUD flakes. Furthermore, the GN/ExF, rGO/ATS, and rGO/TUD flakes significantly reduced the expression of extracellular receptors (uPar, CD105) in U87 glioblastoma cells. In conclusion, the cytotoxic mechanism of rGO flakes may depend on the presence and types of oxygen-containing functional groups, which are more abundant in rGO compared to GN.

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Particle Size of Drug Nanocarriers Defines the Fate of Spinal Cord Injury’s Recovery

10.21203/rs.3.rs-530238/v1 ◽

2021 ◽

Author(s):

Delaram Poormoghadam ◽

Bita Rasoulian Shiadeh ◽

Fereshte Azedi ◽

Hani Tavakol ◽

Seyed Mahdi Rezayat ◽

...

Keyword(s):

Spinal Cord ◽

Cell Membrane ◽

Muscular Atrophy ◽

Muscle Tone ◽

Membrane Damage ◽

Definitive Treatment ◽

Detrusor Muscle ◽

Cell Membrane Damage ◽

Fty 720 ◽

Cord Injury

Abstract Spinal cord injury (SCI) is a debilitating condition for which no definitive treatment has yet been identified. Noteworthy, it influences other tissues through inflammatory reactions and metabolic disturbance. Therefore, fingolimod (FTY-720) as an FDA-approved inflammatory modulator would be promising. In the present study, nanocarriers at two distinct monodisperse particle sizes of 60 (nF60) and 190 (nF190) nm were prepared.The neural stem cell (NSC) viability and LDH release were studied in the face of the nanocarriers and free FTY-720. Results indicated that nanocarriers and free FTY-720 enhanced NSC viability than the control group.However, nF190 significantly induced less cell membrane damage than nF60. Nanocarriers and free FTY-720 enhanced motor neuron recovery in SCI rats, while body weight and return to bladder reflux by nF190 was significantly higher than nF60 groups. Return to bladder reflux might be due to the role of FTY-720 in regulation of detrusor muscle tone and preservation of the integrity of vessels by acting on endothelial cells. Moreover,nF190 gained higher soleus muscle weight than the free drugs;probably decreasing pro-inflammatory cytokines in soleus diminish muscular atrophy in SCI rats.To sum thing up, larger nanacarrirs with less cell membrane damage seems to be more efficient than smaller ones to manage SCI.

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Surface chemistry modification of silica nanoparticles alters the activation of monocytes

Therapeutic Delivery ◽

10.4155/tde-2021-0006 ◽

2021 ◽

Author(s):

Romina Mitarotonda ◽

Martín Saraceno ◽

Marcos Todone ◽

Exequiel Giorgi ◽

Emilio L Malchiodi ◽

...

Keyword(s):

Flow Cytometry ◽

Immune System ◽

Cell Membrane ◽

Cell Activation ◽

Membrane Damage ◽

Living Cells ◽

Cell Membrane Damage ◽

Study Materials ◽

Therapeutic Molecules ◽

Pro Inflammatory Cytokines

Aim: Nanoparticles (NPs) interaction with immune system is a growing topic of study. Materials & methods: Bare and amine grafted silica NPs effects on monocytes/macrophages cells were analyzed by flow cytometry, MTT test and LIVE/DEAD® viability/cytotoxicity assay. Results: Bare silica NPs inhibited proliferation and induced monocyte/macrophages activation (increasing CD40/CD80 expression besides pro-inflammatory cytokines and nitrite secretion). Furthermore, silica NPs increased cell membrane damage and reduced the number of living cells. In contrast, amine grafted silica NPs did not alter these parameters. Conclusion: Cell activation properties of bare silica NPs could be hindered after grafting with amine moieties. This strategy is useful to tune the immune system stimulation by NPs or to design NPs suitable to transport therapeutic molecules.

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