DNA barcoding: a way forward to obtain deep insights about the realistic diversity of living organisms

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Advances in Nematode Identification: A Journey from Fundamentals to Evolutionary Aspects

Nematodes are non-segmented roundworms evenly distributed with various habitats ranging to approximately every ecological extremity. These are the least studied organisms despite being the most diversified group. Nematodes are the most critical equilibrium-maintaining factors, having implications on the yield and health of plants as well as well-being of animals. However, taxonomic knowledge about nematodes is scarce. As a result of the lack of precise taxonomic features, nematode taxonomy remains uncertain. Morphology-based identification has proved inefficacious in identifying and exploring the diversity of nematodes, as there are insufficient morphological variations. Different molecular and new evolving methodologies have been employed to augment morphology-based approaches and bypass these difficulties with varying effectiveness. These identification techniques vary from molecular-based targeting DNA or protein-based targeting amino acid sequences to methods for image processing. High-throughput approaches such as next-generation sequencing have also been added to this league. These alternative approaches have helped to classify nematodes and enhanced the base for increased diversity and phylogeny of nematodes, thus helping to formulate increasingly more nematode bases for use as model organisms to study different hot topics about human well-being. Here, we discuss all the methods of nematode identification as an essential shift from classical morphometric studies to the most important modern-day and molecular approaches for their identification. Classification varies from DNA/protein-based methods to the use of new emerging methods. However, the priority of the method relies on the quality, quantity, and availability of nematode resources and down-streaming applications. This paper reviews all currently offered methods for the detection of nematodes and known/unknown and cryptic or sibling species, emphasizing modern-day methods and budding molecular techniques

Deformation of Nanowires and Nanotubes

In this article, we have investigated the consequences of the next to the leading order correction to the effective field theory of nanostructures. This has been done by analyzing the effects of deformed Heisenberg algebra on nanowires and nanotubes. We first deform the Schrodinger equation with cylindrical topology. Then specific solutions to the deformed Schrodinger equation with different boundary conditions are studied. These deformed solutions are used to investigate the consequences of the deformation on the energy of nanowires and nanotubes.Comment: 9 pages, 6 figure

Chemoprotective effect of taurine on potassium bromate-induced DNA damage, DNA-protein cross-linking and oxidative stress in rat intestine.

Potassium bromate (KBrO3) is widely used as a food additive and is a major water disinfection by-product. It induces multiple organ toxicity in humans and experimental animals and is a probable human carcinogen. The present study reports the protective effect of dietary antioxidant taurine on KBrO3-induced damage to the rat intestine. Animals were randomly divided into four groups: control, KBrO3 alone, taurine alone and taurine+ KBrO3. Administration of KBrO3 alone led to decrease in the activities of intestinal brush border membrane enzymes while those of antioxidant defence and carbohydrate metabolism were also severely altered. There was increase in DNA damage and DNA-protein cross-linking. Treatment with taurine, prior to administration of KBrO3, resulted in significant attenuation in all these parameters but the administration of taurine alone had no effect. Histological studies supported these biochemical results showing extensive intestinal damage in KBrO3-treated animals and greatly reduced tissue injury in the taurine+ KBrO3 group. These results show that taurine ameliorates bromate induced tissue toxicity and oxidative damage by improving the antioxidant defence, tissue integrity and energy metabolism. Taurine can, therefore, be potentially used as a therapeutic/protective agent against toxicity of KBrO3 and related compounds

Histology of hematoxylin and eosin stained sections of rat intestine (duodenum section).

<p>Duodenum in the untreated control (A) shows normal epithelia of both villi and intestinal glands whereas KBrO₃ treated group (B) reveals extensive damage of both components with the lumen being filled with debris. The taurine alone group (C) shows reasonably well preserved condition of both components while taurine+KBrO₃ treated group (D) shows resumption in the morphology of both villi and intestinal glands. Intestinal villi are shown by black arrow and intestinal crypts by green arrow. Magnification is 200 X, scale bar [−] = 50 μm.</p

Effect of taurine pre-treatment on KBrO₃-induced changes in the activities of BBM enzyme in the intestinal homogenates.

<p>Effect of taurine pre-treatment on KBrO₃-induced changes in the activities of BBM enzyme in the intestinal homogenates.</p

Comet assay of intestinal mucosal cells to assess the degree of DNA breakage.

<p>(A) Mucosal cells were subjected to alkaline single cell gel electrophoresis (comet assay) and visualized under a fluorescent microscope after staining the DNA with ethidium bromide. I: Control; II: KBrO₃ alone; III: taurine alone; IV: taurine+KBrO₃. (B) Comet tail lengths. The results of comet assay in panel (A) are represented as mean values of tail lengths. *Significantly different at p < 0.05 from control. † Significantly different at p < 0.05 from KBrO₃-treated group. ǂ Significantly different at p < 0.05 from KBrO₃ and taurine+KBrO₃ treated group.</p

Effect of taurine pre-treatment on KBrO₃-induced changes in the activities of enzymes of carbohydrate metabolism in intestinal homogenates.

<p>Effect of taurine pre-treatment on KBrO₃-induced changes in the activities of enzymes of carbohydrate metabolism in intestinal homogenates.</p

Effect of taurine pre-treatment on KBrO₃-induced changes in the activities of BBM enzymes in isolated BBMV.

<p>Effect of taurine pre-treatment on KBrO₃-induced changes in the activities of BBM enzymes in isolated BBMV.</p

Chemoprotective effects of taurine on KBrO₃ induced alterations in intestinal cell metabolism, membrane integrity and oxidative stress: a summary.

<p>AO: antioxidant; BBM: brush border membrane; DPC: DNA-protein cross-links; KBr: potassium bromide; KBrO₃: potassium bromate; ROS: reactive oxygen species; SH: sulfhydryl; T: taurine.</p