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Impact of Sulphur Dioxide Deposition on Medicinal Plants' Growth and Production of Active Constituents
Published in Azamal Husen, Environmental Pollution and Medicinal Plants, 2022
Shakeelur Rahman, Azamal Husen
The leaf tissue injured by SO2 exposed by microscopic assessment that the mesophyll cells affected with the chloroplasts become plasmolysed and the spongy cells are frequently more affected than the palisade. It has also been seen that the epidermis cells are also plasmolysed under severe conditions. The genotypes of timothy (Phleum pratense) from the location of a gas plant were examined for SO2 sensitivity. The plants were measured resistant when they expressed no signs of visible injury and no significant decreases in shoot or root dry weights compared to control plants (Clapperton and Reid 1994). Hazy shapes of stomata found in Pongamia pinnata exposed to drain pollution resulted from lowering of pH in the cytoplasm of guard cells and thus change in the turgor relations of the stomata complex (Kondo et al. 1980) due to physiological injury within the leaf (Ashenden and Mansfield 1978). Rai and Mishra (2013) added that the plants growing along the roadsides have modified leaf surface characteristics, including stomata and epidermal cells, due to the stress of vehicular pollution.
Basic Microbiology
Published in Philip A. Geis, Cosmetic Microbiology, 2020
Free-living bacteria require protection against osmotic stresses. Osmotic stress is encountered when bacteria enter hypotonic or hypertonic environments depending on the concentration of solutes within the cell. This can lead water to cross the plasma membrane by osmosis in an attempt to normalize solute concentrations across the membrane. Excess gain of water can cause the bacteria to lyse or explode due to cellular swelling whereas excess loss of water can cause membrane rupture by excessive shrinkage (plasmolysis). Most bacteria utilize a carbohydrate-based cell wall in order to provide resistance to osmotic forces. The basis of the cell wall is a macromolecular complex unique to bacteria called “peptidoglycan” or murein (Figure 1.4). The basic repeating structure of peptidoglycan is a disaccharide comprising N-acetylglucosamine (NAG) linked to N-acetylmuramic acid (NAM). This disaccharide is repeated hundreds of times to build long carbohydrate chains that are linked together by short peptides (called stem peptides) that contain unusual amino acids, some not found in proteins. These long chains appear to be wound into helices first and then cross-linked to other helices to form the peptidoglycan structure (2). The peptidoglycan is attached firmly to the cell membrane by lipoproteins. Although bacteria have proteins that determine the overall morphology of the cell, the peptidoglycan reinforces that morphology.
Lysis Protein
Published in Paul Pumpens, Single-Stranded RNA Phages, 2020
The specific localization of the MS2 lysis protein in the membrane adhesion sites of the E. coli cell wall was determined by immunoelectron microscopy (Walderich and Höltje 1989). Thus, the lysis protein was present mostly in clusters of the adhesion sites visible after plasmolysis. In contrast, a quite different distribution of the lysis protein was found in the cells grown under conditions of penicillin tolerance, i.e., at pH 5, a condition that protected cells from the lysis protein−induced lysis. It was concluded that lysis of the E. coli host was a result of the formation of specific lysis protein−mediated membrane adhesion sites (Walderich and Höltje 1989).
Cellular biogenesis of metal nanoparticles by water velvet (Azolla pinnata): different fates of the uptake Fe3+ and Ni2+ to transform into nanoparticles
Published in Artificial Cells, Nanomedicine, and Biotechnology, 2021
Ratima Janthima, Sineenat Siri
Figure 6 shows the representative TEM images of vascular cells of A. pinnata roots exposed to Fe(NO3)3 and both Fe(NO3)3 and Ni(NO3)2. With Fe(NO3)3 exposure, FeNPs were observed near the cell wall of the metaxylem and in paramural bodies of pericycle cells. With both metal treatments, FeNPs also localized near the cell membrane of pericycle cells. The plasmolysis was also observed. It was likely due to the osmosis of water to the outside of the cell in a hypertonic environment. The average diameter of FeNPs in vascular cells was 18.53 ± 10.24 nm, which their diameters ranged from 4.47 to 52.86 nm.
Bacillus Calmette–Guérin Infection and Cytotoxicity in the Retinal Pigment Epithelium
Published in Ocular Immunology and Inflammation, 2018
Victor Llorenç, Marina Mesquida, Blanca Molins, Julián González-Martín, Maite Sainz de la Maza, Alfredo Adán
Cells from infected and control cultures were processed at 3, 24, 48, 72, and 96 h as follows: after trypsinization cell count was made by trypan blue stain in a Neubauer counting chamber. A total of 50 μL of cell suspension was mixed in 10 mL double-distilled sterile water and kept for plasmolysis, shaken for 5 min, and then 50 μL of lysed cell suspension (50 μL of the culture well suspension diluted 1/200) were serially diluted and cultured in Lowenstein–Jensen media. Colony forming units (CFU) were counted after 4 weeks of incubation. The infection rate was calculated as the number of CFU/mL divided by the number of cells/mL of cell suspension at each time point.
Vision of bacterial ghosts as drug carriers mandates accepting the effect of cell membrane on drug loading
Published in Drug Development and Industrial Pharmacy, 2020
Fars K. Alanazi, Abdulaziz A. Alsuwyeh, Nazrul Haq, Mounir M. Salem-Bekhit, Abdullah Al-Dhfyan, Faiyaz Shakeel
Based on these results, the higher loading efficiency was achieved at tonicity of 0.9%. However, since no considerably difference between 0.9% and 0.7% were observed, tonicity 0.7% was preferred and selected to avoid bacterial raptured or plasmolysis at 0.9% tonicity in presence of High DOX concentration (10 mg/mL). When, cells are placed in high tonicity environments, plasmolysis occurs due to reductions in cytoplasmic volume because of water loss by osmosis. The thin peptidoglycan layer of Gram-negative microorganisms is anchored to the cytoplasmic membrane and can be distended by plasmolysis or even ruptured when plasmolysis is more extreme [28].