Antimicrobial peptides as effective tools for enhanced disease resistance in plants

Plant Cell, Tissue and Organ Culture (PCTOC) - Four serotypes of the dengue virus that can cause severe disease in humans greatly increases the complexity of vaccine development. In this study, we...     

Which option best estimates the above-ground biomass of mangroves of Bangladesh: pantropical or site- and species-specific models?

Wetlands Ecology and Management - Bangladesh has the single largest tract of naturally growing mangrove forest as well as the world’s largest manmade mangrove forest on newly accreted land in...     

New N-benzhydrylpiperazine/1,3,4-oxadiazoles conjugates inhibit the proliferation,migration, and induce apoptosis in HeLa cancer cells via oxidative stress–mediated mitochondrial pathway

N-benzhydrylpiperazine and 1,3,4-oxadiazoles are pharmacologically active scaffolds which exhibits significant inhibitory growth effects against various cancer cells, however, antiproliferation effects and the underlying mechanism for inducing apoptosis for aforementioned scaffolds addressing HeLa cancer cells remains uncertain. In this study, N-benzhydrylpiperazine clubbed with 1,3,4-oxadiazoles ( 4a–4h ) were synthesized, subsequently characterized using high resolution spectroscopic techniques and eventually evaluated for their antiproliferation potential by inducing apoptosis in HeLa cancer cells. The MTT assay screening results revealed that among all, compound 4d ( N-benzhydryl-4-((5-(4-aminophenyl)-1,3,4-oxadiazol-2-yl)methyl)piperazine) in particular, exhibited IC ₅₀ value of 28.13 ± 0.21 μg/mL and significantly inhibited the proliferation of HeLa cancer cells in concentration-dependent manner. The in vitro anticancer assays for treated HeLa cells resulted in alterations in the cell morphology, reduction in colony formation, and inhibition of cell migration in concentration-dependent treatment. Furthermore, G2/M phase arrest, variations in the nuclear morphology, degradation of chromosomal DNA confirmed the ongoing apoptosis in treated HeLa cells. Increase in the expression of cytochrome C and caspase-3 confirmed the involvement of intrinsic mitochondrial pathway regulating the cell death. Also, elevation in reactive oxygen species level and loss of mitochondrial membrane potential signified that compound 4d induced apoptosis in HeLa cells by generating the oxidative stress. Therefore, compound 4d may act as a potent chemotherapeutic agent against human cervical cancer.     

Foliar characteristics,cambial activity and wood formation in Azadirachta indica A. Juss. as affected by coal–smoke pollution

This study, aimed at elucidating changes in the foliar and cambial behavior in Azadirachta indica (Neem tree) due to coal-smoke pollution, has revealed inhibitory effects of pollution stress on leaf pigments concentrations, nitrate reductase activity and the contents of reducing sugars and total N content, whereas stimulatory effects were given on stomatal index and nitrate and sulphur contents. Under smoke effects, stomatal conductance was low, leading to a drop in the net photosynthetic rate and a rise in the internal CO₂ concentration of leaf. Cambial reactivation in the stem was delayed at the polluted site. Although the total span of the cambial activity was reduced, greater amount of wood was observed to accumulate in the stem axis under heavy pollution stress. Vessel proportion in the wood increased, whereas size of vessel elements and xylem fibers decreased. “Vulnerability factor” (ratio between mean vessel diameter and mean vessel abundance) and “mesomorphic ratio” (multiplication product of vulnerability factor and mean length of vessel element) of the stem–wood, both declined with increase in the pollution stress, thus indicating a tendency of the species for shifting towards xeromorphy when grown under stress. Given the opposite trends of photosynthetic rate and wood increment, the carbon-partitioning pattern rather than the photosynthetic rate seems to have influenced the accumulation of new wood. The Neem tree proves to be suitable for growing in the polluted areas.     

Analysis of N-glycans of pathological tau: possible occurrence of aberrant processing of tau in Alzheimer's disease

In a previous study [Wang et al. (1996) Nat. Med. 2, 871-875], Wang et al. found (i) that abnormally hyperphosphorylated tau (AD P-tau) isolated from Alzheimer's disease (AD) brain as paired helical filaments (PHF)-tau and as cytosolic AD P-tau but not tau from normal brain were stained by lectins, and (ii) that on in vitro deglycosylation the PHF untwisted into sheets of thin straight filaments, suggesting that tau only in AD brains is glycosylated. To elucidate the primary structure of N-glycans, we comparatively analyzed the N-glycan structures obtained from PHF-tau and AD P-tau. More than half of N-glycans found in PHF-tau and AD P-tau were different. High mannose-type sugar chains and truncated N-glycans were found in both taus in addition to a small amount of sialylated bi- and triantennary sugar chains. More truncated glycans were richer in PHF-tau than AD P-tau. This enrichment of more truncated glycans in PHF might be involved in promoting the assembly and or stabilizing the pathological fibrils in AD.     

Mediated pathogenicity of the baculovirus AcMNPV by the venom from Euplectrus comstockii Howard (Hymenoptera: Eulophidae)

The compatibility of the venom from the parasitic species Euplectrus comstockii Howard (Hymenoptera: Eulophidae) with the pathogenicity of Autographa californica (Speyer) (Lepidoptera: Noctuidae) MNPV baculovirus (AcMNPV) was tested in third and fourth instar larvae of Trichoplusia ni (Hübner) (Lepidoptera: Noctuidae). The presence of AcMNPV did not alter the ability of the venom to arrest ecdysis in T. ni larvae. The presence of the venom delayed the rate of viruses by AcMNPV but increased the total mortality rates from days 9 to 14 in both third and fourth instar T. ni larvae. The delay in viruses was minimized by administering the virus prior to envenomation. In the presence of the venom, the final LD50 values were lower for fourth instar larvae than for third instar larvae. Surface response equations were developed to visualize the effect of the venom on the viruses caused by AcMNPV.     

Age-dependent renal accumulation of 4-hydroxy-2-nonenal (HNE)-modified proteins following parenteral administration of ferric nitrilotriacetate commensurate with its differential toxicity: implications for the involvement of HNE-protein adducts in oxidative stress and carcinogenesis

In this study, we show that the toxicity of ferric nitrilotriacetate (Fe-NTA) can be correlated with the tissue accumulation of 4-hydroxy-2-nonenal (HNE)-modified protein adducts. It is observed that the toxic manifestations of Fe-NTA gradually increase with the increasing age of animals. A dose of Fe-NTA which produces almost 100% mortality in aged rats causes 70% mortality in adults, 30% in pups, 20% in litters, and less than 10% in neonates. The age-dependent increase in its toxicity is also evident from the data of renal microsomal lipid peroxidation and hydrogen peroxide generation. No significant difference in the generation of H2O2 and induction of renal microsomal lipid peroxidation between saline- and Fe-NTA-treated neonates, litters, and pups could be observed. However, in adult rats, a significant increase in both of the parameters was observed which was even greater in aged rats. On the contrary, renal glutathione levels in these animals show an inverse relationship with the oxidant generation. In neonates, litters, and pups the maximum decrease of glutathione was up to 22%, whereas in adult and aged rats, the depletion was more than 60% of their respective saline-treated controls. Parallel to this data, blood urea nitrogen and creatinine, the indicators of renal damage, show a significant increase in Fe-NTA-treated adult and aged rats only, whereas no significant alterations were observed in other groups. Similarly, the magnitude of ODC induction and [3H]thymidine incorporation was much higher in aged and adult rats in comparison to other groups of animals after Fe-NTA treatment. Additionally, the immunohistochemical localization studies show a significant increase in HNE-modified protein adducts in kidney of adult and aged rats, whereas no significant staining was observed in other groups. A similar increase in the level of protein carbonyls has also been observed with the increasing age of rats. These data suggest that the toxicity of Fe-NTA increases with the increasing age of rats and correlates with the accumulation of HNE-modified protein adducts. It may also be speculated that Fe-NTA-mediated renal toxicity leading to carcinogenesis may be related to the tissue accumulation of HNE-modified protein adducts. However, further studies are needed to establish a definite role of HNE-modified proteins in Fe-NTA-mediated carcinogenesis.     

The oil of Adenanthera pavonina L. seeds and its emulsions

The oil of Adenanthera pavonina L. seeds was analysed by chromatographic and instrumental means. The oil was found to be rich in neutral lipids (86.2%), and low in polar lipids (13.8%). The neutral lipids consisted mainly of triacylglycerols (64.2%). Unsaturated fatty acids were found as high as 71%, while the percentage of saturated fatty acids was only 29%. GC and GC/MS analyses revealed linoleic, oleic and lignocerotic acid to be predominant among all fatty acids in the A. pavonina oil, whereas stigmasterol was the major steroid identified within this study. Subsequently, the oil was used for preparation of submicron oil-in-water (o/w) lipid emulsions. Lipid emulsions were formulated by using soybean lecithin (SL) to investigate their particle size, Zeta potential and stability at the different oil and SL ratios. The results obtained indicate possible applications of the tested oil in pharmaceutical and medical fields as drug and cosmetic active ingredient carriers.     

Lipoxygenase inhibiting and antioxidant oligostilbene and monoterpene galactoside from Paeonia emodi

Paeoninol and paeonin C, oligostilbene and monoterpene galactoside, have been isolated from the methanolic extract of the fruits of Paeonia emodi. Their structures have been assigned on the basis of spectral analysis including 1D and 2D NMR techniques. In addition, 4-hydroxybenzoic acid 3, gallic acid 4 and methyl gallate 5 have also been reported for the first time from this species. Compounds 1 and 2 have displayed potent inhibitory potential against enzyme lipoxygenase in a concentration-dependent fashion with the IC(50) values 0.77 and 99.5 microM, along with ABTS(.+) radical quenching activity with IC(50) values of 147.5 and 498.2 microM, respectively.