Priyali Chauhan

Perspective in Antimalarial Chemotherapy

Antimalarial chemotherapy has become more complex and challenging because of multidrug resistant strains of Plasmodium falciparum. Due to resistance of malarial parasite against well known drugs, the chemotherapy of malaria has become complicated. In this review we have discussed brief introduction followed by life cycle of malaria parasite. The list of commercially available antimalarial drugs along with there action on different stages of parasite have been discussed. A brief description of their mechanism of action and advantages and disadvantages were reported. The natural products as antimalarial have been discussed in the review. On the basis of chemical classes the natural products were divided in the following categories; Quinoline alkaloids, Iso-quinoline alkaloids, Indoloquinoline alkaloids, Carbolines, Bis-isoquinoline, 4-Quinazole derivatives, Trioxanes, Terpenes, Naphthoquinone, Anthraquinones, Chalcones, Hydroxy flavanones, Coumarins and phenolic glycoside. The combination chemotherapy has been highlighted in the review. The Biochemical and Immunological changes in malarial infection are discussed along with complications of malarial chemotherapy due to resistance. In the conclusion section, the future strategies for the chemotherapy of malaria have been discussed.

Marker assisted selection and crop management for salt tolerance: A review

Salinity is one of the major abiotic constraints for crop management in irrigated as well as rainfed areas and results to poor harvests. The yield reduction in salt affected soils can be overcome by soil reclamation or by improving salt tolerance in crops. The saline soils can be reclaimed by leaching the salt and cultivation of salt tolerance crops. Rice is known as a good reclamation crop. Salt tolerance is a complex polygenic trait. Insufficient knowledge about mechanism of its inheritance results to slow progress in its introgression into target crops. The role of traditional as well as marker assisted breeding approaches has been discussed for introgression of salt tolerance in crops in order to obtain better harvests. Key word : Abiotic constraints, salinity, crop management, introgression, traditional breeding, marker assisted selection.

Solid Phase Synthesis of Structurally Diverse Tetra Substituted Pyrimidines for Potential Use in Combinatorial Chemistry

A new pyrimidine based scaffold has been identified for generation of combinatorial libraries using solid phase technique. The utility of the scaffolds was demonstrated by synthesizing small libraries of 12 substituted pyrimidines (4a-4l).

Morphometric and rheological study of lunar domes of Marius Hills volcanic complex region using Chandrayaan-1 and recent datasets

Marius Hills volcanic complex is one of the most important regions on the lunar surface having an abundant number of volcanic features like domes and cones. Systematic mapping of 106 domes/cones in the Marius Hills region was carried out in this study using high-resolution orthoimage and digital elevation models of Chandrayaan-1 and Kaguya missions. Various morphometric parameters like diameter, height, volume, flank slope, circularity index and form factor are derived for all the mapped domes. The rheological parameters, such as viscosity and eruption rate are estimated for isolated domes and cones superimposed over low domes. The morphometric and rheological properties of these domes are comparable to those located in the area near to Hortensius crater and other mare regions. Surface ages derived for a selected region in NW portion of the Marius Hills volcanic complex using crater size-frequency distribution technique yields ages of 2.98 and 1.91 Ga. It suggests that the domes in this region formed at about 2.98 Ga ago, and then, the younger mare basalts likely embayed this region about 1.98 Ga ago. Stratigraphic sequence of rilles, wrinkle ridge and domes shows that wrinkle ridges are the oldest, while the rilles are younger than the domes.

Quantitative Evaluation of Apically Extruded Debris of Different Single File Systems: WaveOne Gold, One Shape, F360, and Reciproc: An in vitro Study

dimensional obturation. During the process, the debris of the root canal system is pushed out from the canals, leading to treatment failure and flare-ups.1 Many factors contribute to debris extrusion. According,2 irrigation of the root canal space during instrumentation is one of the factors that led to an increased amount of debris extrusion. Teeth with necrotic pulp permitted more irrigant extrusion compared with vital teeth. The depth of file insertion into the root canal is another factor affecting debris extrusion. Studies conducted 3,4 showed that instrumentation short of apical foramen decreased the amount of debris extrusion with both endosonic and k-files. Canal preparation done with step-back techniques showed greater amount of periapical extrusion, whereas canal preparation having special design of nickel–titanium files with crown-down technique decreases the amount of extrusion periapically.2 The amount of apical extrusion can also vary according to the technique used. It is generally accepted that instrumentation techniques that incorporate rotational action generate less debris than push/ pull instrumentation, and the crown-down technique has been associated with the least amount of debris extrusion, compared with techniques involving a linear filing motion. Thus, engine-driven rotary systems have tended to extrude less debris than hand techniques. Recently, newer file system WaveOne Gold has been introduced, which was compared with F360, One Shape, and Reciproc. The Reciproc files are composed of M-Wire nickel– titanium, which offers increased flexibility. The reciprocating movement of the instrument reduces the risk of cyclic fatigue. One Shape files, on the contrary, employ traditional continuous rotation. They have a triangle-shaped cutting edge and two additional cutting edges, in the apical and coronal parts, as well as a cross-section that progressively changes from three to two cutting edges between the apical and coronal parts. This design offers optimal cutting action.1,3 F360 has a double S-shaped cutting edges and a lower bending ability increasing the flexibility of file. It has a 1Professor and Head, 2Professor, 3-8Postgraduate Student (3rd Year) 1-8Department of Conservative Dentistry and Endodontics, Divya Jyoti College of Dental Sciences & Research, Ghaziabad, Uttar Pradesh, India

Comparative Evaluation of Fractured Resistance of Different Post System in Endodontically treated Teeth: An in vitro Study

Reconstruction of endodontically treated teeth is a great challenge in restorative dentistry since the tooth crown is usually totally or partially lost by caries, erosion, abrasion, previous restorations, trauma, or endodontic access. If more than half of the coronal structure has been lost, a root canal post is required to provide retention for the restoration.1 When assessing an endodontically treated tooth for restorative treatment, it has to be assumed that good judgments have been made previously concerning the periodontal status of the tooth, the remaining tooth structure, and the prognosis of the endodontic treatment. The tooth to be restored should exhibit a good apical seal when evaluating the radiograph, and also exhibit no sensitivity to percussion or palpation, no exudates, no fistula, no apical sensitivity, and no active inflammation.2 Although posts are recommended to strengthen the teeth, several investigators have cautioned that posts with inadequate resistance to rotational forces on the posts can weaken the teeth. Consequently, root fractures constitute the most serious type of failure in post restored teeth. To prevent root fractures, a post should have an elastic modulus similar to that of dentin – a property that enables a more uniform distribution of stress by distributing the occlusal load. On the contrary, while it is important to ensure that a post is firmly cemented to provide adequate retention for the restoration and adequate protection of the remaining tooth structure, it should yet be easily removed if retreatment were required.3

An In-Vitro Evaluation of Remaining Dentine Thickness through Cbct Using Different Files

Aim: The present study was undertaken to compare and evaluate the remaining dentin thickness of root canals with ProTaper Golr, NeoEndo and Revo-S systems using cone beam computed tomography for analysis. Materials and Methods: Forty five extracted human mandibular molars having were collected. Teeth were randomly assigned to three groups (n=15). Samples were decoronized by maintaining root length. Pre-instrumentation cone beam computed tomography scan was done after stabilizing the samples on wax blocks. The working length was determined at 1 mm short from the apical foramen by using a ISO 15 K-fi le tip protruding at apical foramen. Preparation was carried out according to the manufacturer’s instructions. Finally, canals were instrumented upto apically for each group. After each instrumentation, root canals were irrigated with 2ml of 3% sodium hypochlorite solution followed by 2 ml of 17% EDTA solution. Final irrigation was done with 5ml of saline. Post instrumentation cone beam computed tomography scans of all samples in the 3 groups were acquired. Result: revo-s and NeoEndo removed less dentin than Protaper Gold file system. Conclusion: Protaper Gold, NeoEndo and Revo-S showed statistically significant difference in remaining dentin thickness over the different intervals of root canal length. Therefore, it was concluded that Protaper Gold file system removed more dentine than RevoS and NeoEndo file system.