Multiple Sclerosis
Irun R. Cohen in Perspectives on Autoimmunity, 2020
Direct cellular observations have been limited to the relatively few B-cells found in the CSF.195,210,237 A high proportion of these secrete immunoglobulin without in vitro stimulation or show intracytoplasmic immunoglobulin.195,261,262 This proportion is frequently higher than is found with peripheral blood B-cells in the same individuals, and it is clear that these cells are activated. Use of pokeweed mitogen stimulates an additional proportion to produce Ig, but this test does not differentiate these cells from those in the CSF of individuals with other neurologic diseases.210,262 The finding that many or most of the CSF B-cells are activated is in accord with inferences from the study of CSF immunoglobulins, already discussed, and with the view that they may in part represent long-term lines or clones of Ig-producing cells. However, phenotypic marker studies have yet to be done, and these cells cannot be considered representative of the B-cell or plasma cell population in perivascular spaces within the CNS on the basis of present information.
The Structural Biology, Biochemistry, Toxicology, and Military Use of the Ricin Toxin and the Associated Treatments and Medical Countermeasures for Ricin Exposure
Brian J. Lukey, James A. Romano, Salem Harry in Chemical Warfare Agents, 2019
Although all RIPs exhibit N-glycosidase activity toward ribosomes, they display marked differences in substrate specificity. Most type I toxins exhibit very broad specificities, whereas type II toxins display a preference for animal ribosomes. Ricin, for example, is highly active against mammalian and yeast ribosomes but poorly active, or even inactive, against plant and bacterial ribosomes (Yoshinari et al., 1997). Pokeweed antiviral protein, on the other hand, depurinates ribosomes from plants, bacteria, yeast, and various evolutionally diverse animals (Rajamohan et al., 1999). Both the RIP and the ribosome of an RIP–ribosome complex contribute to the apparent substrate specificity (Kurinov et al., 1999). Because the rRNA sarcin–ricin loop architecture is universally conserved, the broad range of specificities displayed by different RIPs may possibly reside within the associated ribosomal proteins conferring tertiary structure to the ribosome (Kurinov et al., 1999), which either facilitate or hinder access of the RIPs to the sarcin–ricin loop. Vater et al. (1995) identified the rat liver ribosomal proteins L9 and L10e as the binding target of RTA and yeast ribosomal protein L3 as the binding factor for pokeweed antiviral protein. In addition to the highly specific action on ribosomes, ricin and related RIPs have a less specific action in vitro on single- and double-stranded DNA, RNA substrates releasing multiple adenine nucleotides, and guanine nucleotides in some instances (Wang and Tumer, 1999). RTA also catalyzes the hydrolysis of synthetic oligonucleotides as short as six base pairs, provided that a specific tetra loop of guanosine and adenosine nucleotides is present (Amukele and Schramm, 2004).
Inherited Defects in Immune Defenses Leading to Pulmonary Disease
Stephen D. Litwin in Genetic Determinants of Pulmonary Disease, 2020
Bloom's syndrome is also an autosomal recessive disease found predominantly among Ashkenazic Jews. The major features are growth retardation, a characteristic telangiectactic rash, a high frequency of chromosomal rearrangements, and malignancy [147]. Recently it has been shown that individuals with this inherited disease have relatively subtle immune defects which include a poor response of their lymphocytes in vitro to pokeweed mitogen, and variable abnormalities of their serum Ig values [148]. The above data is consistent with observations of an increased incidence of infectious diseases in the first decade of life.
Recent developments in vaccines and biological therapies against Japanese encephalitis virus
Published in Expert Opinion on Biological Therapy, 2018
Several inhibitors acting at a postentry stage of flavivirus infection have been developed. These include a derivate of the protein secondary structure mimetic bispidine conjugated with hydrophobic amino acid residues, which showed antiviral properties against JEV in vitro, probably by inhibition of viral genome replication [157]. Pokeweed, a plant-derived N-glycosidase ribosomal-inactivating protein isolated from Phytolacca americana, is a broad-spectrum antiviral protein that inhibits protein translation by depurination of rRNA. In vitro and in vivo experiments showed that pokeweed inhibited JEV replication and nanomolar concentration and conferred partial protection against JEV lethal infection in mice [158]. The antiparasitic drug nitazoxanide was shown to have also antiviral activity against a variety of viruses through different mechanisms. Regarding JEV, nitazoxanide inhibits JEV replication in cell culture and daily intragastric administration of the drug led to 90% reduction of the mortality of mice challenged with a lethal dose of JEV [159].
Plant identification applications do not reliably identify toxic and edible plants in the American Midwest
Published in Clinical Toxicology, 2023
Kevan Long, Andrew Townesmith, Alex Overmiller, Wendy Applequist, Anthony Scalzo, Paula Buchanan, Cindy C. Bitter
We also included several plants that are edible with proper preparation. Ripened fruits of Podophyllum peltatum (mayapple) are edible, while green fruits contain podophyllotoxin, from which the antineoplastic agents etoposide and teniposide were derived. Young shoots of the Phytolacca americana (pokeweed) plant are edible if cooked, while older shoots, roots, and berries from the plant contain saponins and pokeweed mitogen, which causes nausea, vomiting, and diarrhea which can be severe [19]. Elderberries (Sambucus spp.) contain a cyanide-inducing glycoside, but cooking neutralizes the compound [33]. Misidentification of fruits and berries has caused toxicity in humans [21,29].
Role of Mushroom as Dietary Supplement on Performance of Poultry
Published in Journal of Dietary Supplements, 2019
Sohail Hassan Khan, Nasir Mukhtar, Javid Iqbal
Molting in poultry is used to rejuvenate hens for a second or third laying cycle. Feed withdrawal was once the most effective method used for molt induction; however, it has been phased out due to food safety and animal welfare concerns. In some studies, mushrooms were used as a safe and effective alternative for inducing molt, enhancing immunity, reducing Salmonella growth, and returning to egg production. Willis et al. (2008) evaluated the efficiency of medicinal mushroom (shiitake) and pokeweed extract combined with alfalfa on the induction of a molt, weight loss, Salmonella population, and postmolt egg production in older hens. The results indicated that body weight loss, ovary regression, and return to egg production were not adversely affected by the two extracts utilized in this experiment. A greater decrease in the natural Salmonella population in the ceca and crop was obtained with the combination of full-fed alfalfa plus mushroom extract in molting hens, and it induced a comparable molt with feed withdrawal. The mechanism is not clear regarding the combined effect of alfalfa and mushroom extract to decrease the Salmonella population. A possible explanation could come from the work of Hinton et al. (2000). They indicated that feed withdrawal purges the crop of fermentable carbohydrates that lactic acid–producing bacteria require for growth and lactic acid production. This action generally allows an increase in the numbers of Salmonellae and other Enterobacteriaceae. The polysaccharides provided by the mushroom extract could have optimized this process. There was also a significant reduction of Salmonella in the crop with the combination of alfalfa meal plus pokeweed. Willis et al. (2009) evaluated the use of feeding fungus-myceliated (FM) sorghum grain on molt induction, postmolt production, Salmonella, and humoral immunity response in laying hens. The results showed that egg production for the FM group ceased completely by day 5, whereas hens in the FM + alfalfa group ceased egg production by day 6. The percentage of body weight loss decreased significantly in FM group (35%) and FM + alfalfa group (37%) than control group (57%). Return to egg production differed between treatments with higher production beginning in the FM group and ending in the FM + alfalfa group. However, no differences in antibody production could be attributed to the supplementation of fungus-myceliated grain.
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