High-throughput virtual screening and molecular dynamics simulation reveals NPC170742 a novel chalconoid compound as a potential inhibitor of D-glycero-D-manno-heptose-1,7-bisphosphate 7-phosphatase in Helicobacter pylori.

Helicobacter pylori is a gram negative spiral shaped bacteria that causes peptic ulcer and gastric cancer. It Is the sixth most prevalent cancer in the world and the third leading cause of cancer death. The increase in reported cases of H. pylori resistance to the drugs and antibiotics shows the need for the development of new and efficient drugs against the pathogen. In the present study, D-glycero-D-manno-heptose-1,7-bisphosphate 7-phosphatase (GmhB), an enzyme involved in the biosynthesis of lipopolysaccharides that encourages bacterial adherence, self-aggregation and identifying the host cells was modelled and the active sites were predicted through POCASA which is an automated ligand binding site prediction server. Natural product activity and species source (NPASS) is a database of 96,481 natural compounds that were subjected to virtual screening workflow that includes Qikprop, Lipinski rule, filtering out reactive functional groups followed by high throughput virtual screening and the top 10 compounds were selected for further induced fit docking along with the substrate D-glycero-ß-D-manno-heptose 1,7-bisphosphate. The compound NPC170742 (Alpha, Beta, 3,4,5,2',4',6'-Octahydroxy dihydrochalcone) showed higher affinity than the substrate, and both the substrate D-glycero-ß-D-manno-heptose 1,7-bisphosphate and the compound NPC170742 were subjected to molecular dynamics simulation. The results exposed the compound NPC170742 could be a potential lead compound against the enzyme D-glycero-D-manno-heptose-1,7-bisphosphate 7-phosphatase of H. pylori.Communicated by Ramaswamy H. Sarma.

Effect of graphene nanopaint on performance of solar air heater attached with inclined and winglet baffles.

Solar air heater is widely used for drying and industrial processing application. Different artificial roughened surfaces and coatings over the absorber plates are used to improve their performance of solar air heater by increasing absorption and heat transfer. In this proposed work, the graphene-based nanopaint is prepared by wet chemical and ball milling method and the prepared graphene nanopaint is characterized using Fourier transform infrared spectroscopy (FTIR) and X-ray diffraction (XRD). The prepared graphene-based nanopaint is coated on the absorber plate by conventional coating method. The thermal performance of the solar air heater coated with traditional black paint and graphene nanopaint is evaluated and compared. The day's maximum energy gain by the graphene-coated solar air heater is 972.84 W, whereas traditional black paint is only 808.02 W. The average energy gain of graphene nanopaint is 655.85 W, which is 12.9% higher than the traditional black paint. The maximum thermal efficiency for solar air heater coated with graphene nanopaint is 81%. Also the average thermal efficiency of graphene-coated solar air heater is 72.5%, which has a 13.24% higher average thermal efficiency when compared to conventional black paint-coated solar air heater. The average top heat loss for solar air heater coated with graphene nanopaint is 8.48% lower than solar air heater with traditional black paint.

Enhancing the performance of a solar air heater by employing the broken V-shaped ribs.

This work aims to enhance the performance of a solar air heater (SAH) by introducing broken V-ribs as roughness elements on the absorber plate. The unit with a conventional flat absorber plate is referred to as the "FSAH," while the unit with a broken V-rib-shaped absorber plate is called the "VSAH." The experiment was performed for three air velocities: 25 m/s, 20 m/s, and 15 m/s and the corresponding air flow rates were 0.037 kg/s, 0.031 kg/s, and 0.023 kg/s, respectively. The results showed that the maximum temperature was experienced on the absorber plate, followed by the glass plate for both SAHs. Overall, the average absorber and glass plate temperatures of the VSAH were 0.6-1.4 °C and 0.4-1.9 °C lower than those of the FSAH. Compared to the FSAH, the experimental results showed that the VSAH experienced useful power and thermal efficiency that were 16.6-19.8% and 15.7-20.4% higher, respectively, while the top surface heat losses were found to decrease by 2.1-8.1%. Due to the disrupted air paths in the VSAH, the observed pressure drop was 113.3-133.3% higher than that of the FSAH. More impotently, the thermo-hydraulic performance factor was always higher 1 and the observed values were 1.48, 1.39, and 1.24 at the va (velocity) values of 15, 20, and 25 m/s, respectively. Therefore, the proposed VSAH had an admirable thermal performance as compared to FSAH. Further, optimization through varying the roughness parameters, namely, relative blockage width (W/w), relative pitch ratio (P/e), number of baffles (n), relative blockage height (e/H), and angle of attack (ß) could helped to achieve better performance.

Environmental, economic, and performance assessment of solar air heater with inclined and winglet baffle.

To investigate the solar air heater's (SAH) effectiveness, experiments are conducted using flat plate and artificially roughened plate in terms of inclined and winglet baffles over the collector surface. This proposed system collector plate is made up of inclined and winglet ribs and serves as an artificial roughness generator. Air stream of 0.01, 0.02, and 0.03 kg/s are used in the experiment. To determine the improvement in the proposed work, these experimental results are compared with flat plate SAH. This proposed work offers a greater efficiency, useful energy gain, and lower top heat loss than a conventional SAH. At 0.03 kg/s system efficiency and useful energy gain reach their peak. Experimental day's average efficiency of a SAH with inclined and winglet baffles is 30.8%, 52.7%, and 72.9%, respectively, for the examined cases, and it is 11%, 13.8%, and 22.2% more effective than a flat surface SAH. For the investigated air flow rates, the proposed system gains 36.2%, 24.2%, and 28.9% more energy than flat plate SAH. Substantial reductions in top losses of up to 8.48%, 7.28%, and 7.27% have been reported at the specified flow rates, respectively. Energy metrics and economic study performed show the payback time, production factor, life cycle conversion efficiency, and economic values of the proposed SAH are optimum.

Experimental study on the thermal performance of a solar air heater integrated with multi-geometry arrangements over the absorber plate.

A solar air heater (SAH) is investigated experimentally by employing multi-geometry arrangements over the absorber plate. In the current work, the absorber plate is designed with rectangular ribs, slits, and cylinders. For the proposed system, this multi-geometry arrangement serves as an artificial roughness (baffles). Different airflow rates of 0.01, 0.02, 0.03, and 0.04 kg/s are used in the experiment. The results of this experiment are compared to those of a conventional SAH to assess the improvement. Compared to a conventional SAH, the proposed system has higher thermal efficiency, energy gain, and minimal top loss. The highest thermal efficiency and energy gain are observed at a mass flow rate of 0.04 kg/s. Increasing the mass flow rate increases the system's performance. For the analyzed flow rates, the average thermal efficiency of a SAH with multi-geometry baffle is 40.8%, 58.2%, 68.2%, and 77.4%. For the same flow rates, it is 12.8%, 10.2%, 12.3%, and 13.5% higher than a conventional SAH. For the same examined air flow rates, the suggested air heater gains 31.9%, 21%, 19.2%, and 20.8% more energy than conventional SAH. Significant decreases in top losses are reported up to 8.1%, 7.3%, 7.2%, and 6.5%, respectively for the specified flow rates.

Draft Genome of the Liver Fluke Fasciola gigantica.

Fascioliasis, a neglected foodborne disease caused by liver flukes (genus Fasciola), affects more than 200 million people worldwide. Despite technological advances, little is known about the molecular biology and biochemistry of these flukes. We present the draft genome of Fasciola gigantica for the first time. The assembled draft genome has a size of ∼1.04 Gb with an N50 and N90 of 129 and 149 kb, respectively. A total of 20 858 genes were predicted. The de novo repeats identified in the draft genome were 46.85%. The pathway included all of the genes of glycolysis, Krebs cycle, and fatty acid metabolism but lacked the key genes of the fatty acid biosynthesis pathway. This indicates that the fatty acid required for survival of the fluke may be acquired from the host bile. It may be hypothesized that the relatively larger F. gigantica genome did not evolve through genome duplications but rather is interspersed with many repetitive elements. The genomic information will provide a comprehensive resource to facilitate the development of novel interventions for fascioliasis control.

Structure-function studies of the asparaginyl-tRNA synthetase from Fasciola gigantica: understanding the role of catalytic and non-catalytic domains.

The asparaginyl-tRNA synthetase (NRS) catalyzes the attachment of asparagine to its cognate tRNA during translation. NRS first catalyzes the binding of Asn and ATP to form the NRS-asparaginyl adenylate complex, followed by the esterification of Asn to its tRNA. We investigated the role of constituent domains in regulating the structure and activity of Fasciola gigantica NRS (FgNRS). We cloned the full-length FgNRS, along with its various truncated forms, expressed, and purified the corresponding proteins. Size exclusion chromatography indicated a role of the anticodon-binding domain (ABD) of FgNRS in protein dimerization. The N-terminal domain (NTD) was not essential for cognate tRNA binding, and the hinge region between the ABD and the C-terminal domain (CTD) was crucial for regulating the enzymatic activity. Molecular docking and fluorescence quenching experiments elucidated the binding affinities of the substrates to various domains. The molecular dynamics simulation of the modeled protein showed the presence of an unstructured region between the NTD and ABD that exhibited a large number of conformations over time, and further analysis indicated this region to be intrinsically disordered. The present study provides information on the structural and functional regulation, protein-substrate(s) interactions and dynamics, and the role of non-catalytic domains in regulating the activity of FgNRS.

Aminoacyl-tRNA synthetases: Structure, function, and drug discovery.

Aminoacyl-tRNA synthetases (AARSs) are the enzymes that catalyze the aminoacylation reaction by covalently linking an amino acid to its cognate tRNA in the first step of protein translation. Beyond this classical function, these enzymes are also known to have a role in several metabolic and signaling pathways that are important for cell viability. Study of these enzymes is of great interest to the researchers due to its pivotal role in the growth and survival of an organism. Further, unfolding the interesting structural and functional aspects of these enzymes in the last few years has qualified them as a potential drug target against various diseases. Here we review the classification, function, and the conserved as well the appended structural architecture of these enzymes in detail, including its association with multi-synthetase complexes. We also considered their role in human diseases in terms of mutations and autoantibodies against AARSs. Finally, we have discussed the available inhibitors against AARSs. This review offers comprehensive information on AARSs under a single canopy that would be a good inventory for researchers working in this area.

Antihyperlipidemic activity of Cassia auriculata flower extract in oleic acid induced hyperlipidemia in Saccharomyces cerevisiae.

The Cassia auriculata herb has been traditionally used in India for medicinal purposes to treat hyperglycemia, diabetes, rheumatism, asthma, and skin diseases. In the present study, ethanolic extract of Cassia auriculata flower (Et-CAF) depicted anti-hyperlipidemic effect in the budding yeast cells. The hyperlipidemic conditions were induced in the yeast cells with oleic acid which showed an increase in triacylglycerol (TAG) and sterol esters (SE), and was supported by the mRNA expression of LRO1 and DGA1 (involved in TAG formation); as well as ARE1 and ARE2 (involved in SE formation). The anti-hyperlipidemic effect by the Et-CAF was compared with the commercial drug Atorvastatin. The lipid droplets were increased in the hyperlipidemic yeast cell that was observed under the confocal microscope with BODIPY staining; Atorvastatin and Et-CAF reduced the lipid droplets. This study revealed that the anti-hyperlipidemic effect in Et-CAF has gained importance and might be used to fill the gap created by the allopathic drugs.

Keratomycosis Caused By Graphium eumorphum (Graphium State of Scedosporium apiospermum).

Graphium eumorphum is rarely associated with mycotic keratitis. We report the case of a 30-year-old female presented with complaints of redness and defective vision in the left eye for one month. Gram staining and 10% KOH wet mount of corneal smears revealed fungal filaments. On potato dextrose agar, fast growing greyish white colonies turning grayish black on maturity was obtained. Lactophenol cotton blue (LPCB) staining confirmed the isolate as Graphium eumorphum. The infection was resolved with the combination of natamycin, econazole and itraconazole.

Solitary bone cyst of the mandible: a case report and brief review of literature.

A solitary bone cyst is a non-neoplastic osseous lesion comprising 1% of all the cysts affecting the jaws. They are generally asymptomatic, usually detected incidentally during routine radiological assessment and are less common in the mandibular anterior region. This article presents a well-documented case involving a solitary bone cyst affecting the mandibular symphysis in a 12-year-old boy with no history of previous trauma. Simple curettage of the bone cavity resulted in the resolution of the lesion with progressive osseous regeneration. No evidence of recurrence was noted 2 years after the treatment.

Single-rooted primary first mandibular molar.

Morphological variations like single-rooted molar in primary dentition are scarce. Understanding the root canal anatomy and variations is necessary for successful root canal therapy. The purpose of the present article is to report successful endodontic treatment of primary left mandibular first molar with an abnormal morphology of a single root. This case report highlights the importance of knowledge and its applications in the management of anomalous anatomic variants which play a crucial role in the success of endodontic treatment.