Phytotoxic effects of β-pinene on early growth and associated biochemical changes in rice

β-Pinene, an oxygenated monoterpene, is one of the major monoterpenes emitted into the atmosphere from forest areas and trees. Besides, it is a principal component of essential oils of a number of aromatic plants, which are involved in a variety of ecological interactions, including allelopathy, in the natural environment. However, studies pertaining to phytotoxicity and biochemical effect(s) of β-pinene are largely lacking. We investigated the effect of β-pinene (0.02, 0.04, 0.08, 0.20, 0.40 and 0.80 mg/ml) in a dose- and time-dependent manner on early seedling growth, dry weight accumulation, photosynthetic pigments and changes in macromolecule (protein and carbohydrate) content and activities of enzymes—proteases, α- and β-amylases, polyphenol oxidases and peroxidases- in rice (Oryza sativa) after 3rd, 5th and 7th day of exposure. β-pinene (≥0.04 mg/ml) significantly reduced the root (by 13–87%) and coleoptile (by 5–80%) length of rice. Exposure to β-pinene reduced total chlorophyll content in rice coleoptiles suggesting a negative impact on photosynthesis. The content of macromolecules (proteins and carbohydrates) enhanced significantly in response to β-pinene, whereas the activities of hydrolyzing enzymes—proteases, α-amylases, and β-amylases—declined (by 30–85, 26–84, 27–74%, respectively) in β-pinene-exposed seedlings. In contrast, the activities of peroxidases (POX) and polyphenol oxidases (PPO) enhanced significantly (by 16–152 and 53–290%, respectively) in rice roots in response to β-pinene in a dose- and time-dependent manner. Increased activities of POX and PPO indicate their involvement in providing protection and/or conferring resistance against β-pinene-induced stress. The study concludes that β-pinene inhibits the early growth of rice by altering the plant biochemical status and enhancing activities of POXs and PPOs involved in general plant defense.     

Improving the developability of an anti-EphA2 single-chain variable fragment for nanoparticle targeting

Antibody-targeted nanoparticles have great promise as anti-cancer drugs; however, substantial developmental challenges of antibody modules prevent many candidates from reaching the clinic. Here, we describe a robust strategy for developing an EphA2-targeting antibody fragment for immunoliposomal drug delivery. A highly bioactive single-chain variable fragment (scFv) was engineered to overcome developmental liabilities, including low thermostability and weak binding to affinity purification resins. Improved thermostability was achieved by modifying the framework of the scFv, and complementarity-determining region (CDR)-H2 was modified to increase binding to protein A resins. The results of our engineering campaigns demonstrate that it is possible, using focused design strategies, to rapidly improve the stability and manufacturing characteristics of an antibody fragment for use as a component of a novel therapeutic construct.     

Effects of some imidazoles on cellular immune responses--an experimental study.

Effects of some imidazole compounds were studied on two animal models of cellular immune responses. Metronidazole in doses of 100 and 200 mg/kg and cimetidine 200mg/kg (ip), significantly suppressed the delayed type of hypersensitivity reaction, as evidenced by the footpad thickness method in mice. No significant alteration in the response could be observed however, in tinidazole treated groups. All the three drugs inhibited the migration of leucocytes in the presence of antigen in rats considerably. However, they did not produce any involution of spleen or reduction of adrenal weight indicating that their actions are not corticosteroid mediated. All the three drugs studied are histamine-like imidazole derivatives. H2 receptors are present on the surface of T-lymphocytes. They appear to modulate the cellular immune response by altering the function of the regulatory lymphocytes.     

Effect of simazine and atrazine on the mineralization of fertilizer and manure nitrogen

Summary Laboratory experiments were carried out with alluvial sandy loam soil to study the effect of simazine and atrazine herbicides at four levels (0.5, 1.0, 1.5 and 2.0 kg/ha) on the mineralization of nitrogen (ammoniacal and nitrate production) from fertilizer urea and sludge sources. The herbicides stimulated nitrate production. No specific trend in total mineralized nitrogen, ammoniacal and nitrate nitrogen was observed by varying the levels of herbicides. Mineralization of total nitrogen (ammoniacal and nitrate nitrogen) in presence of simazine and atrazine from the different sources in the descending order was:Urea > Sludge + Urea > Sludge > No Nitrogen.     

Optimisation of skin phototype classification

Understanding individuals' skin pigmentation and photosensitivity is important in judging risk of skin cancer and response to certain treatment modalities. However, individuals with darkly pigmented skin are poorly represented in the widely used Fitzpatrick skin phototype (FST) system. Moreover, the FST system is prone to misuse, as it relies on subjective patient and clinician assessment of skin type, and does not clearly differentiate pigmentation from photosensitivity. By evaluating the key literature surrounding the FST system, its criticisms and proposed alternatives, this review serves to understand how skin phototype classification can be optimised.     

The HSP GRP94 interacts with macrophage intracellular complement C3 and impacts M2 profile during ER stress

The role of GRP94, an endoplasmic reticulum (ER) stress protein with both pro- and anti-inflammatory functions, has not been investigated in macrophages during ER stress, whereas ER stress has been reported in many diseases involving macrophages. In this work, we studied GRP94 in M1/LPS + IFNγ and M2/IL-4 primary macrophages derived from human monocytes (isolated from buffy coats), in basal and ER stress conditions induced by thapsigargin (Tg), an inducer of ER calcium depletion and tunicamycin (Tm), an inhibitor of N-glycosylation. We found that GRP94 was expressed on the membrane of M2 but not M1 macrophages. In M2, Tg, but not Tm, while decreased GRP94 content in the membrane, it induced its secretion. This correlated with the induction of a pro-inflammatory profile, which was dependent on the UPR IRE1α arm activation and on a functional GRP94. As we previously reported that GRP94 associated with complement C3 at the extracellular level, we analyzed C3 and confirmed GRP94-C3 interaction in our experimental model. Further, Tg increased this interaction and, in these conditions, C3b and cathepsin L were detected in the extracellular medium where GRP94 co-immunoprecipitated with C3 and C3b. Finally, we showed that the C3b inactivated fragment, iC3b, only present on non-stressed M2, depended on functional GRP94, making both GRP94 and iC3b potential markers of M2 cells. In conclusion, our results show that GRP94 is co-secreted with C3 under ER stress conditions which may facilitate its cleavage by cathepsin L, thus contributing to the pro-inflammatory profile observed in stressed M2 macrophages.Subject terms: Immunology, Innate immune cells     

Up regulation of the GRP-78 and GADD-153 and down regulation of Bcl-2 proteins in primary glomerular diseases: a possible involvement of the ER stress pathway in glomerulonephritis

Alpha-lipoic acid (LA) has recently been reported to afford protection against neurodegenerative disorders in humans and experimental animals. However, the mechanisms underlying LA-mediated neuroprotection remain an enigma. Because peroxynitrite has been extensively implicated in the pathogenesis of various forms of neurodegenerative disorders, this study was undertaken to investigate the effects of LA in peroxynitrite-induced DNA strand breaks, a critical event leading to peroxynitrite-elicited cytotoxicity. Incubation of φX-174 plasmid DNA with the 3-morpholinosydnonimine (SIN-1), a peroxynitrite generator, led to the formation of both single- and double-stranded DNA breaks in a concentration- and time-dependent fashion. The presence of LA at 100–1,600 μM was found to significantly inhibit SIN-1-induced DNA strand breaks in a concentration-dependent manner. The consumption of oxygen induced by 250 μM SIN-1 was found to be decreased in the presence of high concentrations of LA (400–1,600 μM), indicating that LA at these concentrations may affect the generation of peroxynitrite from auto-oxidation of SIN-1. It is observed that incubation of the plasmid DNA with authentic peroxynitrite resulted in a significant formation of DNA strand breaks, which could also be dramatically inhibited by the presence of LA (100–1,600 μM). EPR spectroscopy in combination with spin-trapping experiments, using 5,5-dimethylpyrroline-N-oxide (DMPO) as spin trap, resulted in the formation of DMPO-hydroxyl radical adduct (DMPO-OH) from authentic peroxynitrite and LA at 50–1,600 μM inhibited the adduct signal. Taken together, these studies demonstrate for the first time that LA can potently inhibit peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation. In view of the critical involvement of peroxynitrite in the pathogenesis of various neurodegenerative diseases, the inhibition of peroxynitrite-mediated DNA damage by LA may be responsible, at least partially, for its neuroprotective activities.     

Application of calcium alginate immobilized and crude pectin lyase from Bacillus cereus in degumming of plant fibres

Abstract

In this study, the purified pectin lyase was immobilized in calcium alginate beads and compared with crude enzyme for application in degumming of buel and banana plant fibres. From the data of scanning electron microscopy (SEM), it was observed that untreated buel fibres were covered by non-cellulosic materials (pectin, hemicelluloses and waxes) and the surface of enzymatically treated buel fibres looked smoother. Also, the crude alkaline pectin lyase treated buel fibre exhibited a considerably cleaner surface, which suggested that the crude pectin lyase could provide better degumming effects in comparison to the immobilized pectin lyase. In case of banana fibre, the FTIR spectroscopy showed that both crude and immobilized alkaline pectin lyase treatments of banana plant fibres were equally efficient in degumming. The enzymatic degumming of buel and banana with crude pectin lyase resulted in maximum release of galacturonide after 24?h for buel and 15?h for banana fibre. The optimum temperature for degumming of buel and banana fibres with crude pectin lyase was found to be 50?°C and 45?°C, respectively. Also, the maximum galacturonide was released with 200 and 250?U of pectin lyase for buel and banana fibre, respectively.