Search

Electron microscope (EM) was developed in 1931 and since then microscopical examination of both the biological and non‐biological samples has been revolutionized. Modifications in electron microscopy techniques, such as scanning EM and transmission EM, have widened their applicability in the various sectors such as understanding of drug toxicity, development of mechanism, criminal site investigation, and characterization of the nano‐molecule. The present review summarizes its role in important aspects such as toxicity assessment and disease diagnosis in special reference to SARS‐COV2. In the biological system, EM studies have elucidated the impact of toxicants at the ultra‐structural level in various tissue in conformity to physiological alterations. Thus, EM can be concluded as an important tool in toxicity assessment and disease prognosis. [ABSTRACT FROM AUTHOR]

The present study aimed at assessing the singular and combined effects of water copper and polyvinyl chloride microplastic (MPVC) on intestinal copper accumulation, histopathological damage, and stress‐/immune‐related genes' expression in common carp, Cyprinus carpio. Four groups of fish were maintained in triplicate: control (kept in clean water), Cu (exposed to 0.25 mg/L of copper), MPVC (exposed to 0.5 mg/L of MPVC), and Cu‐MPVC (exposed to 0.25 mg/L of copper + 0.5 mg/L of MPVC). After 14‐day exposure, the fish of Cu and Cu‐MPVC treatments exhibited significantly higher intestinal copper contents, compared to the fish of control and MPVC treatments. In this regard, the Cu‐MPVC fish had significantly higher copper content than the Cu fish. Exposure to copper and/or MPVC significantly upregulated the intestinal heat shock protein 70 (hsp70), cytochrome P450 family 1 subfamily A member 1 (cyp1a1), lysozyme (lys), defensin (def), mucin 2 (muc2), and mucin 5 (muc5) expression. The highest expression of hsp70, cyp1a1, lys, and def was related to Cu‐MPVC treatment; whereas, the highest expression of muc2 and muc5 was observed in Cu and MPVC treatments. Exposure to copper and/or MPVC induced intestinal damage, which Cu‐MPVC fish exhibited the highest severity. The present study revealed that exposure to copper and/or MPVC causes intestinal histopathological damage and upregulation in stress‐ and immune‐related genes' expression. The most serious effects were observed in Cu‐MPVC treatment that might be due to additive effects of copper and MPVC and/or higher copper accumulation in this treatment. Highlights: Presence of polyvinyl chloride microparticles (MPVC) in Cu‐contaminated water increase fish' intestinal copperCopper and/or MPVC upregulate intestinal stress‐ and immune‐related gene expressionsCopper and/or MPVC induce histopathological damages to the fish intestineCoexposure to copper and MPVC increases the negative changes in the fish intestine [ABSTRACT FROM AUTHOR]

Blood is a sensitive bioindicator of stress observed by organisms in response to toxicants. Erythrocytic morphological abnormalities serve as a reliable determinant of fish health. Malachite green, a multifunctional dye was assessed for toxicity in Cyprinus carpio. Dye‐induced blood toxicity has been determined through biochemical and ultra structural endpoints at 15, 30 and 60 days in the fish. Further, an attempt has been made to combat the adverse effects of the toxicant through supplementation with Emblica officinalis. Electron microscopic study depicted erythrocytic remodelling in form of surface blebbing, lobopodial projections and shrinkage; appearance of crenate, acanthocytes, echinocytes, dacrocytes, spherocytes and rhomboidal cells. Hepatic marker enzymes showed significantly (p < 0.05) elevated levels of biomarker enzymes, alkaline phosphatase, serum glutamate oxaloacetate transaminase and serum glutamate pyruvate transaminase. Contrarily feeding with E. officinalis extract (1,000 mg/kg feed) significantly attenuated biochemical and morphological alterations, indicating the protective efficacy of E. officinalis. Both toxicity and attenuation observed were in exposure‐dependent manner. [ABSTRACT FROM AUTHOR]