Retailers play a vital role in supply chain management because they deal directly with consumers. Occasionally, retailers may cover the entire system's statistics and not disclose these data to the manufacturer. Therefore, asymmetry is generated in the data throughout the system.
View Article and Find Full Text PDFPlastic pollution has been reported to negatively impact global biodiversity and ecosystem health. However, the molecular mechanisms of nano-plastics in plants are unidentified, especially their negative impacts on genomic stability. This study for the first time showed that nano-polystyrene leads to cell death in plants by subjugating the cellular antioxidant defence mechanisms through the aggravated production of ROS, which in turn could induce the DNA damage impairing the genetic regulation of the corresponding DNA repair pathway.
View Article and Find Full Text PDFMelatonin is an important biomolecule found in diverse groups of organisms. Under different abiotic stresses, the synthesis of melatonin is markedly increased suggesting pivotal roles of melatonin in plants enduring stresses. Being an endogenous signaling molecule with antioxidant activity, melatonin alters many physiological responses and is found to be involved in regulating DNA damage responses.
View Article and Find Full Text PDFMany studies have investigated the negative impacts of microplastics on teleost fishes with very little or no evidence of their mechanism of action. This scenario entreats us to investigate the toxicities of nanopolystyrene in zebrafish oocyte with emphasis on the mechanism of action. In the present study, the cellular levels of mRNA transcripts of different genetic markers (such as: sod, gpx, nrf2, inos, ucp2, and atp6 (redox-sensitive markers); nfkβ, tnfα, il-10, ikβ, gdf9, and bmp15 (immune markers); gadd45, rad51, p53 and bcl2 (DNA damage and apoptotic)) have been quantified by real-time PCR after 6 h of incubation of isolated oocyte with different doses of nanopolystyrene viz.
View Article and Find Full Text PDFSome recent studies have reviewed the occurrence and phytotoxicity of micro/nanoplastics, but their distribution in the soil environment, mechanisms of uptake by roots and the mode of action are unclear. Thus, this review comprehensively represents the relative abundance of micro/nanoplastics in different soil types and their toxicities in plants with insights into their partitioning to different soil matrices, uptake mechanisms, and the mode of action. Partitioning of micro/nanoplastics to different soil matrices (like-soil particles, naturally occurring soil organic matters, pore waters and soil fauna) could modify their bioavailability to plants.
View Article and Find Full Text PDFThe phenomenon of eutrophication leads to the global occurrence of algal blooms. Cyanotoxins as produced by many cyanobacterial species can lead to detrimental effects to the biome due to their stability and potential biomagnification along food webs. Therefore, understanding of the potential risks these toxins pose to the most susceptible organisms is an important prerequisite for ecological risks assessment of cyanobacteria blooms.
View Article and Find Full Text PDFInteractions of plastic particles with different organic/inorganic pollutants including heavy metals impact their ecotoxicological potential, and proper understanding in this regard is important for their ecological risk assessment. However, many studies have reported the interactions between micro-/nanoplastics (MNPs) and heavy metals (HMs), but the most prevalent interactive forces and factors monitoring their interactions are still not clear. So, the present review represents the mechanisms of interactions with special emphasis on major interactive forces and biophysicochemical and environmental factors influencing trace element's adsorption onto the surface of MNPs.
View Article and Find Full Text PDFCyanotoxins (CTX) and micro/nanoplastics (M/NP) are ubiquitously distributed in every environmental compartment. But the distribution, abundance and associated ecological risks of CTX are still poorly understood in soil system. On the other hand, M/NP could serve as vectors for persistent organic/inorganic pollutants in the natural environment through the sorption of pollutants onto them.
View Article and Find Full Text PDFEscalated production of plastic, their worldwide distribution and persistent nature finally results into their environmental accumulation causing severe threats to the ecological environment and biotic health. Thus, development of suitable measurements for environmental remediation of plastic may be an urgent issue in this plastic age. Some recent reviews have categorized the microbial species able to degrade different plastic polymers and the different factors effecting bio-degradation of plastic are poorly understood.
View Article and Find Full Text PDFConventional chemical approaches for synthesizing nanoparticles (NPs) may restrict their applicability as they are not eco-friendly, energetically efficient and often involve toxic reducing/capping agents; but phytonanotechnology enabled the synthesis of safe, inexpensive, highly biocompatible NPs. In this regard, thorough understanding of green components and the modulatory effects of different reaction conditions on the physicochemical parameters of green synthesized NPs would be a prerequisite, which is not depicted elsewhere. This review critically analyzes the relevant reaction conditions from their mechanistic viewpoints in plant-based synthesis of NPs arising fundamental issues which need to be determined carefully.
View Article and Find Full Text PDFIn mammals, interleukin 6 (IL-6) has an important function during ovulation, however, the functions of IL-6 in fish have not been elucidated. In the present study, there was quantification of de novo synthesis of ovarian IL-6 and tumor necrosis factor-alpha (TNFα) in control and hCG-treated fish and results were compared with those from an in vitro study where there was evaluation of the regulatory functions of gonadotropins and TNFα of IL-6 secretions. Relatively greater concentrations of ovarian IL-6 at the post-GVBD (post-germinal vesicle breakdown) stage indicates IL-6 modulates ovulatory processes.
View Article and Find Full Text PDFPlastic pollution represents a global concern for the biodiversity conservation, ecosystem and public health. The polystyrene is one of the dominant pollutants in both terrestrial and aquatic ecosystem. This work measured the hazardous nature of 100 nm micropolystyrene (MPS) using 25, 50, 100, 200, and 400 mg/L concentrations in terms of oxidative stress, morphotoxicity and cytogenotoxicity in Allium cepa.
View Article and Find Full Text PDFThe endocrine regulation of gonadal development and annual variation of key sex steroids is the basic knowledge to understand the reproductive cycle of teleost fish. Present study was aimed to investigate the levels of gonadotropins in relation to the follicular development and plasma steroids during the reproductive cycle of female Trichogaster fasciata. Female fish were sampled and ovarian development is described histologically throughout the year in relation to the seasonal variations of gonadosomatic index (GSI); follicle stimulating hormone (FSH) and luteinizing hormone (LH); three key steroids for folliculogenesis and maturation i.
View Article and Find Full Text PDFMercury is one of the key pollutants responsible for the degradation of natural aquatic ecosystems. Among the different forms of mercury that exist in the environment, mercuric chloride (HgCl) is the dominant pollutant for freshwater environments as it is used as an ingredient in antiseptics, disinfectants and preservatives, insecticides, batteries and in metallurgical and photographic operations. Pollutant may exert their action on organisms or populations by affecting their normal endocrine function as well as reproduction.
View Article and Find Full Text PDFPhenylethanolamine N-methyltransferase (PNMT) is the enzyme that catalyzes the S-adenosyl-L-methionine-dependent methylation of (-)norepinephrine to (-)epinephrine in the adrenal medulla. Adrenal PNMT activity is markedly different in two highly inbred rat strains; enzyme activity in the F344 strain is more than fivefold greater than that in the Buf strain. Initial characterization of the enzyme in the two inbred strains reveals evidence for catalytic and structural differences, as reflected in dissimilar Km values for the cosubstrate (S-adenosyl-L-methionine) and prominent differences in thermal inactivation curves.
View Article and Find Full Text PDFThe potential role of brain adrenergic neurons in regulating noradrenergic neuronal metabolism was assessed using inhibitors of phenylethanolamine N-methyltransferase (PNMT), the enzyme responsible for epinephrine production. Two centrally active PNMT inhibitors (SK&F 64139 and LY134046) were administered over a 6-day treatment period to cause prolonged reductions in epinephrine formation. In brain regions containing endogenous epinephrine (medulla-pons and hypothalamus), chronic treatment with PNMT inhibitors produced: 1) reductions of epinephrine content, 2) elevation of tyrosine hydroxylase activity and 3) elevation of alpha-1 and particularly alpha-2 adrenergic receptor radioligand binding sites; neither norepinephrine turnover nor beta adrenergic receptor binding was affected.
View Article and Find Full Text PDFEpinephrine content and PNMT activity in medulla pons and hypothalamus of F344 inbred rats is from 3- to 8-fold higher than that of Buf inbred rats. These strain-dependent differences in brain adrenergic neurons are reciprocally related to altered alpha 1- adn alpha 2-adrenergic receptor density in PNMT-containing brain regions. Radioligand binding indices related to alpha 2-receptor function reveal that receptors may be 'desensitized' as well as 'down-regulated' in the strain with high PNMT activity (F344), and may be 'supersensitive' as well as 'up-regulated' in the strain with low PNMT activity (Buf).
View Article and Find Full Text PDFInbred tht strains Fischer 344 (F344) and Buffalo (BUF) differ in serveral physiological and behavioral measures. It was found that the activity of adrenomedullary and regional brain phenylethanolamine N-methyltransferase is at least four times higher in F344 rats than in BUF rats; these strain-dependent differences corresponded directly with the epinephrine content of the medulla-pons and hypothalamus. Conversely, alpha-adrenergic receptor density in brain regions containing phenylethanolamine N-methyltransferase is two to three times lower in F344 rats than in BUF rats; alpha-receptors in frontal cortex (a brain region lacking phenylethanolamine N-methyltransferase activity and epinephrine) are similar in both strains.
View Article and Find Full Text PDFStandard procedures for the purification of phenylethanolamine N-methyltransferase were modified by the addition of an affinity chromatography step utilizing immobilized S-adenosyl-L-homocysteine and by use of preparative isoelectric focusing. Enzyme derived from bovine adrenal medullae was bound to S-adenosyl-L-homocysteine agarose, and could be eluted with 0.1 M NaCl.
View Article and Find Full Text PDFThe metabolic clearance rate (MCR) of both bovine and rat dopamine beta-hydroxylase (DBH) preparations was measured using two complementary procedures, pulse-dose injection and constant infusion of enzyme into the rat circulation. Rats that received injections of DBH activity had plasma DBH activity levels similar to those of controls by 24 hr after a pulse dose of rat DBH. The DBH MCR computed by stochastic analysis of the disappearance curve of injected DBH activity was about 1.
View Article and Find Full Text PDFThe circadian rhythm of methionine S-adenosyltransferase, which catalyzes the formation of S-adenosylmethionine, a cosubstrate for melatonin in the pineal gland, follows the pattern of hydroxyindole-O-methyltransferase. Around the middle of the dark period, methionine S-adenosyltransferase and hydroxyindole-O-methyltransferase appear to be elevated by 2.5- and 1.
View Article and Find Full Text PDFComp Biochem Physiol C Comp Pharmacol
December 1981
Int J Neurosci
September 1980
In contrast to mammalian tissues, catechol-O-methyltransferase (COMT) activity is localized predominantly, if not entirely, in the cytosolic fraction in the tissues of Biomphalaria glabrata. Enzymatic activity is greater in glycylglycine and Tris-Cl buffers than in phosphate buffer. The pH optimum for this enzymatic reaction is 8.
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