Search results for: entry inhibitors
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 867

Search results for: entry inhibitors

747 Obesity, Metabolic Syndrome and Related Risk Behaviors Among Thai Medical Students of Thammasat University

Authors: Patcharapa Thaweekul, Paskorn Sritipsukho

Abstract:

Background: During the training period of the 6-year medical curriculum, medical students seem to have many risk behaviors of developing obesity. This study aims to demonstrate the prevalence and risk behavior of obesity and related metabolic disorders among the final-year medical students of Thammasat University as well as the change in nutritional status during studying program. Methods: 123 participants were asked to complete the self-report questionnaires. Weight, height, waist circumference and blood pressure were obtained. Blood samples were drawn for total cholesterol, high-density lipoprotein, low-density lipoprotein, triglycerides and plasma glucose. Body weight and height of the medical students in the first year were obtained from the medical report at the entry. Results: The prevalence of overweight and obesity at the entry to medical school was 22.0% and increased to 30.1% in the final year. Two obese students (5.4%) was diagnosed as metabolic syndrome. During 6-year curriculum, the BMI gained in male medical students were more significant as compared to female students (1.76±1.74 and 0.43±1.82 kg/m2, respectively; p <.001). The current BMI is significantly correlated with the BMI at entry. Serum LDL-C in the overweight/obese students was significantly higher as compared to the normal weight and underweight group. Sleep deprivation was a significantly frequent behavior in the overweight/obese students. Conclusion: Medical students, as having high-risk behaviors, should be assessed for the nutritional status and metabolic parameters. Medical schools should promote the healthy behaviors to increase the healthy eating and exercise habits and reduced the risk behaviors among them.

Keywords: medical students, metabolic syndrome, obesity, risk behaviors

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746 Assessment the Manner of Obtaining Hierarchies and Privacy of Traditional Houses Entrance in Providing a Safe Place-Case Study: Traditional Houses in Shiraz

Authors: Zahra A. Barzegar, Maryam B. Golboo

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In this paper, the manner of obtaining hierarchies and privacy entry of traditional houses in providing a safe place in the city of Shiraz will be evaluated by qualitative–descriptive methods and 6 old houses are the case study. The houses of Shiraz, as the houses in other cities in Iran are a response to climate and physical features. The old part of Shiraz has a compressed and dense texture in which the houses are in narrow and tight alleys. In this regard, the principles of traditional house entrance design have been introduced. The results show that every house has a private entrance. Direction of the entry of most houses is toward the south and with a turn to the South-East side. Entrance to yard path in all the cases is not straight, and this had been done by using 90 degrees rotates of the corridor leading to the yard. Vestibule provides a private place for the house and entrance stairway to the rooftop is located inside it.

Keywords: entrance, components of entrance, hierarchy, frontage, Shiraz houses

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745 In Silico Exploration of Quinazoline Derivatives as EGFR Inhibitors for Lung Cancer: A Multi-Modal Approach Integrating QSAR-3D, ADMET, Molecular Docking, and Molecular Dynamics Analyses

Authors: Mohamed Moussaoui

Abstract:

A series of thirty-one potential inhibitors targeting the epidermal growth factor receptor kinase (EGFR), derived from quinazoline, underwent 3D-QSAR analysis using CoMFA and CoMSIA methodologies. The training and test sets of quinazoline derivatives were utilized to construct and validate the QSAR models, respectively, with dataset alignment performed using the lowest energy conformer of the most active compound. The best-performing CoMFA and CoMSIA models demonstrated impressive determination coefficients, with R² values of 0.981 and 0.978, respectively, and Leave One Out cross-validation determination coefficients, Q², of 0.645 and 0.729, respectively. Furthermore, external validation using a test set of five compounds yielded predicted determination coefficients, R² test, of 0.929 and 0.909 for CoMFA and CoMSIA, respectively. Building upon these promising results, eighteen new compounds were designed and assessed for drug likeness and ADMET properties through in silico methods. Additionally, molecular docking studies were conducted to elucidate the binding interactions between the selected compounds and the enzyme. Detailed molecular dynamics simulations were performed to analyze the stability, conformational changes, and binding interactions of the quinazoline derivatives with the EGFR kinase. These simulations provided deeper insights into the dynamic behavior of the compounds within the active site. This comprehensive analysis enhances the understanding of quinazoline derivatives as potential anti-cancer agents and provides valuable insights for lead optimization in the early stages of drug discovery, particularly for developing highly potent anticancer therapeutics

Keywords: 3D-QSAR, CoMFA, CoMSIA, ADMET, molecular docking, quinazoline, molecular dynamic, egfr inhibitors, lung cancer, anticancer

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744 Examining Geometric Thinking Behaviours of Undergraduates in Online Geometry Course

Authors: Peter Akayuure

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Geometry is considered an important strand in mathematics due to its wide-ranging utilitarian value and because it serves as a building block for understanding other aspects of undergraduate mathematics, including algebra and calculus. Matters regarding students’ geometric thinking have therefore long been pursued by mathematics researchers and educators globally via different theoretical lenses, curriculum reform efforts, and innovative instructional practices. However, so far, studies remain inconclusive about the instructional platforms that effectively promote geometric thinking. At the University of Education, Winneba, an undergraduate geometry course was designed and delivered on UEW Learning Management System (LMS) using Moodle platform. This study utilizes van Hiele’s theoretical lens to examine the entry and exit’s geometric thinking behaviours of prospective teachers who took the undergraduate geometry course in the LMS platform. The study was a descriptive survey that involved an intact class of 280 first-year students enrolled to pursue a bachelor's in mathematics education at the university. The van Hiele’s Geometric thinking test was used to assess participants’ entry and exit behaviours, while semi-structured interviews were used to obtain data for triangulation. Data were analysed descriptively and displayed in tables and charts. An Independent t-test was used to test for significant differences in geometric thinking behaviours between those who entered the university with a diploma certificate and with senior high certificate. The results show that on entry, more than 70% of the prospective teachers operated within the visualization level of van Hiele’s geometric thinking. Less than 20% reached analysis and abstraction levels, and no participant reached deduction and rigor levels. On exit, participants’ geometric thinking levels increased markedly across levels, but the difference from entry was not significant and might have occurred by chance. The geometric thinking behaviours of those enrolled with diploma certificates did not differ significant from those enrolled directly from senior high school. The study recommends that the design principles and delivery of undergraduate geometry course via LMS should be structured and tackled using van Hiele’s geometric thinking levels to serve as means of bridging the existing learning gaps of undergraduate students.

Keywords: geometric thinking, van Hiele’s, UEW learning management system, undergraduate geometry

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743 The Digital Desert in Global Business: Digital Analytics as an Oasis of Hope for Sub-Saharan Africa

Authors: David Amoah Oduro

Abstract:

In the ever-evolving terrain of international business, a profound revolution is underway, guided by the swift integration and advancement of disruptive technologies like digital analytics. In today's international business landscape, where competition is fierce, and decisions are data-driven, the essence of this paper lies in offering a tangible roadmap for practitioners. It is a guide that bridges the chasm between theory and actionable insights, helping businesses, investors, and entrepreneurs navigate the complexities of international expansion into sub-Saharan Africa. This practitioner paper distils essential insights, methodologies, and actionable recommendations for businesses seeking to leverage digital analytics in their pursuit of market entry and expansion across the African continent. What sets this paper apart is its unwavering focus on a region ripe with potential: sub-Saharan Africa. The adoption and adaptation of digital analytics are not mere luxuries but essential strategic tools for evaluating countries and entering markets within this dynamic region. With the spotlight firmly fixed on sub-Saharan Africa, the aim is to provide a compelling resource to guide practitioners in their quest to unearth the vast opportunities hidden within sub-Saharan Africa's digital desert. The paper illuminates the pivotal role of digital analytics in providing a data-driven foundation for market entry decisions. It highlights the ability to uncover market trends, consumer behavior, and competitive landscapes. By understanding Africa's incredible diversity, the paper underscores the importance of tailoring market entry strategies to account for unique cultural, economic, and regulatory factors. For practitioners, this paper offers a set of actionable recommendations, including the creation of cross-functional teams, the integration of local expertise, and the cultivation of long-term partnerships to ensure sustainable market entry success. It advocates for a commitment to continuous learning and flexibility in adapting strategies as the African market evolves. This paper represents an invaluable resource for businesses, investors, and entrepreneurs who are keen on unlocking the potential of digital analytics for informed market entry in Africa. It serves as a guiding light, equipping practitioners with the essential tools and insights needed to thrive in this dynamic and diverse continent. With these key insights, methodologies, and recommendations, this paper is a roadmap to prosperous and sustainable market entry in Africa. It is vital for anyone looking to harness the transformational potential of digital analytics to create prosperous and sustainable ventures in a region brimming with promise. In the ever-advancing digital age, this practitioner paper becomes a lodestar, guiding businesses and visionaries toward success amidst the unique challenges and rewards of sub-Saharan Africa's international business landscape.

Keywords: global analytics, digital analytics, sub-Saharan Africa, data analytics

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742 Naltrexone and Borderline Personality Disorder: A Brief Review

Authors: Azadeh Moghaddas, Mehrnoush Dianatkhah, Padideh Ghaeli

Abstract:

The main characteristics of borderline personality disorder (BPD) are instable regulation of affect and self-image, impulsive behavior, and lack of interpersonal relationships. Clinically, emotional dysregulation, impulsive aggression, repeated self-injury, and suicidal thought are noted with this disorder. Proper management of patients with BPD is a difficult challenge due to the complex features of this disorder. Pharmacotherapy of BPD in order to control impulsive behavior and to stabilize affect in patients with BPD has been receiving a lot of attention. Anticonvulsant agents such as topiramate, valproate, or lamotrigine, atypical antipsychotics such as aripiprazole and olanzapine and antidepressants such as monoamine oxidase inhibitors and selective serotonin reuptake inhibitors like fluvoxamine have been implicated in the treatment of BPD. Unfortunately, none of these medications can be used alone or even in combination as sole treatment of BPD. Medications may be used mostly to resolve or reduce impulsivity and aggression in these patients. Naltrexone (NTX), a nonspecific competitive opiate antagonist has been suggested, in the literature, to control self-injurious behavior (SIB) and dissociative symptoms in patients with BPD. This brief review has been intended to look at all documented evidence on the use of NTX in the management of BPD and to reach a comprehensive conclusion.

Keywords: borderline personality disorder, naltrexone, self-injurious behavior, dissociative symptoms

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741 Potential of Polyphenols from Tamarix Gallica towards Common Pathological Features of Diabetes and Alzheimer’s Diseases

Authors: Asma Ben Hmidene, Mizuho Hanaki, Kazuma Murakami, Kazuhiro Irie, Hiroko Isoda, Hideyuki Shigemori

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Type 2 diabetes mellitus (T2DM) and Alzheimer’s disease (AD) are characterized as a peripheral metabolic disorder and a degenerative disease of the central nervous system, respectively. It is now widely recognized that T2DM and AD share many pathophysiological features including glucose metabolism, increased oxidative stress and amyloid aggregation. Amyloid beta (Aβ) is the components of the amyloid deposits in the AD brain and while the component of the amyloidogenic peptide deposit in the pancreatic islets of Langerhans is identified as human islet amyloid polypeptide (hIAPP). These two proteins are originated from the amyloid precursor protein and have a high sequence similarity. Although the amino acid sequences of amyloidogenic proteins are diverse, they all adopt a similar structure in aggregates called cross-beta-spine. Add at that, extensive studies in the past years have found that like Aβ1-42, IAPP forms early intermediate assemblies as spherical oligomers, implicating that these oligomers possess a common folding pattern or conformation. These similarities can be used in the search for effective pharmacotherapy for DM, since potent therapeutic agents such as antioxidants with a catechol moiety, proved to inhibit Aβ aggregation, may play a key role in the inhibit the aggregation of hIAPP treatment of patients with DM. Tamarix gallica is one of the halophyte species having a powerful antioxidant system. Although it was traditionally used for the treatment of various liver metabolic disorders, there is no report about the use of this plant for the treatment or prevention of T2DM and AD. Therefore, the aim of this work is to investigate their protective effect towards T2DM and AD by isolation and identification of α-glucosidase inhibitors, with antioxidant potential, that play an important role in the glucose metabolism in diabetic patient, as well as, the polymerization of hIAPP and Aβ aggregation inhibitors. Structure-activity relationship study was conducted for both assays. And as for α-glucosidase inhibitors, their mechanism of action and their synergistic potential when applied with a very low concentration of acarbose were also suggesting that they can be used not only as α-glucosidase inhibitors but also be combined with established α-glucosidase inhibitors to reduce their adverse effect. The antioxidant potential of the purified substances was evaluated by DPPH and SOD assays. Th-T assay using 42-mer amyloid β-protein (Aβ42) for AD and hIAPP which is a 37-residue peptide secreted by the pancreatic β –cells for T2DM and Transmission electronic microscopy (TEM) were conducted to evaluate the amyloid aggragation of the actives substances. For α-glucosidase, p-NPG and glucose oxidase assays were performed for determining the inhibition potential and structure-activity relationship study. The Enzyme kinetic protocol was used to study the mechanism of action. From this research, it was concluded that polyphenols playing a role in the glucose metabolism and oxidative stress can also inhibit the amyloid aggregation, and that substances with a catechol and glucuronide moieties inhibiting amyloid-β aggregation, might be used to inhibit the aggregation of hIAPP.

Keywords: α-glucosidase inhibitors, amyloid aggregation inhibition, mechanism of action, polyphenols, structure activity relationship, synergistic potential, tamarix gallica

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740 Cannabinoids and Terpenes as Potential Modulators of Efflux Transporters for Overcoming Drug Resistance in Epilepsy

Authors: Tomáš Nejedlý, Dominika Mrázková, Jitka Viktorová

Abstract:

The blood-brain barrier (BBB) serves as a protective shield, preventing the entry of harmful substances into the central nervous system. On the other hand, it also restricts the transport of neuroactive drugs, such as antiepileptics, which mitigate epileptic seizures. Drug-resistant epilepsy is often associated with the overexpression of efflux transporters, including P-glycoprotein (P-gp) or multidrug resistance protein 1 (MRP1), on the BBB. The aim of this work is to find P-gp and MRP1 inhibitors derived from phytocannabinoids and terpenes. The work evaluates whether these compounds interact directly with P-gp or MRP1 by rhodamine 123 or fluorescein efflux assay. The effect of phytocannabinoids on the gene expression of these transporters is also studied using qPCR and Western blot. These transporters are found in BBB cells; however, we decided to use the human ovarian cancer cell line (A2780ADR) due to its overproduction of P-gp and malignant glioma cell line (U87) due to its overproduction of MRP1. The results showed that while terpenes suppressed the activity of efflux transporters, phytocannabinoids tended to decrease their expression. Terpenes demonstrated an average inhibition of 65%, surpassing phytocannabinoids, which exhibited an average inhibition of approximately 30%. Particularly noteworthy was the modulating effect of (-)-α-bisabolol with the highest activity among the compounds tested. Based on these findings, phytocannabinoids and terpenes emerge as promising natural candidates for addressing drug resistance linked to efflux transporters. Acknowledgment: The project was funded by the Grant No 22-20860S of The Czech Science Foundation.

Keywords: drug-resistant epilepsy, efflux transporters, multidrug resistance protein 1, P-glycoprotein, phytocannabinoids, terpens

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739 Efficacy of Celecoxib Adjunct Treatment on Bipolar Disorder: Systematic Review and Meta-Analysis

Authors: Daniela V. Bavaresco, Tamy Colonetti, Antonio Jose Grande, Francesc Colom, Joao Quevedo, Samira S. Valvassori, Maria Ines da Rosa

Abstract:

Objective: Performed a systematic review and meta-analysis to evaluated the potential effect of the cyclo-oxygenases (Cox)-2 inhibitor Celecoxib adjunct treatment in Bipolar Disorder (BD), through of randomized controlled trials. Method: A search of the electronic databases was proceeded, on MEDLINE, EMBASE, Scopus, Cochrane Central Register of Controlled Trials (CENTRAL), Biomed Central, Web of Science, IBECS, LILACS, PsycINFO (American Psychological Association), Congress Abstracts, and Grey literature (Google Scholar and the British Library) for studies published from January 1990 to February 2018. A search strategy was developed using the terms: 'Bipolar disorder' or 'Bipolar mania' or 'Bipolar depression' or 'Bipolar mixed' or 'Bipolar euthymic' and 'Celecoxib' or 'Cyclooxygenase-2 inhibitors' or 'Cox-2 inhibitors' as text words and Medical Subject Headings (i.e., MeSH and EMTREE) and searched. The therapeutic effects of adjunctive treatment with Celecoxib were analyzed, it was possible to carry out a meta-analysis of three studies included in the systematic review. The meta-analysis was performed including the final results of the Young Mania Rating Scale (YMRS) at the end of randomized controlled trials (RCT). Results: Three primary studies were included in the systematic review, with a total of 121 patients. The meta-analysis had significant effect in the YMRS scores from patients with BD who used Celecoxib adjuvant treatment in comparison to placebo. The weighted mean difference was 5.54 (95%CI=3.26-7.82); p < 0.001; I2 =0%). Conclusion: The systematic review suggests that adjuvant treatment with Celecoxib improves the response of major treatments in patients with BD when compared with adjuvant placebo treatment.

Keywords: bipolar disorder, Cox-2 inhibitors, Celecoxib, systematic review, meta-analysis

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738 PEA Design of the Direct Control for Training Motor Drives

Authors: Abdulatif Abdulsalam Mohamed Shaban

Abstract:

This paper states that the art of Procedure Entry Array (PEA) plan with a focus on control system applications. This paper begins with an impression of PEA technology development, followed by an arrangement of design technologies, and the use of programmable description languages and system-level design tools. They allow a practical approach based on a unique model for complete engineering electronics systems. There are three main design rules are implemented in the system. These are algorithm based fine-tuning, modularity, and the control act and the architectural constraints. An overview of contributions and limits of PEAs is also given, followed by a short survey of PEA-based gifted controllers for recent engineering systems. Finally, two complete and timely case studies are presented to illustrate the benefits of a PEA implementation when using the proposed system modelling and devise attitude. These consist of the direct control for training motor drives and the control of a diesel-driven stand-alone generator with the help of logical design.

Keywords: control (DC), engineering electronics systems, training motor drives, procedure entry array

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737 Efficient Reduction of Organophosphate Pesticide from Fruits and Vegetables Using Cost Effective Neutralizer

Authors: Debjani Dasgupta, Aman Zalawadia, Anuj Thapa, Pranjali Sing, Ashish Dabade

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Organophosphate group pesticides are common pesticide group, which gain entry into food product due to incomplete removal of pesticide residues. The current food industry raw material handling process is not sufficient to eliminate pesticide residues. A neutralizer was used to neutralize the residues of pesticide on Vitis vinifera (Grapes). The water based dilution of neutralizer was demonstrated on fruits like grapes. Analysis for pesticides in water wash and neutralizer wash was carried out using GCMS. Fruits washed with neutralizer exhibited 72.95% removal of pesticides compared with normal water wash method. An economical chemical neutralizer can be used to remove such residues in raw material handling at industrial scale with minor modification in process to achieve minimum pesticide entry into final food products.

Keywords: GCMS, organophosphate, raw material handling, Vitis vinifera, pesticide neutralizer

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736 Simulation of Optimum Sculling Angle for Adaptive Rowing

Authors: Pornthep Rachnavy

Abstract:

The purpose of this paper is twofold. First, we believe that there are a significant relationship between sculling angle and sculling style among adaptive rowing. Second, we introduce a methodology used for adaptive rowing, namely simulation, to identify effectiveness of adaptive rowing. For our study we simulate the arms only single scull of adaptive rowing. The method for rowing fastest under the 1000 meter was investigated by study sculling angle using the simulation modeling. A simulation model of a rowing system was developed using the Matlab software package base on equations of motion consist of many variation for moving the boat such as oars length, blade velocity and sculling style. The boat speed, power and energy consumption on the system were compute. This simulation modeling can predict the force acting on the boat. The optimum sculling angle was performing by computer simulation for compute the solution. Input to the model are sculling style of each rower and sculling angle. Outputs of the model are boat velocity at 1000 meter. The present study suggests that the optimum sculling angle exist depends on sculling styles. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the first style is -57.00 and 22.0 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the second style is -57.00 and 22.0 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the third style is -51.57 and 28.65 degree. The optimum angle for blade entry and release with respect to the perpendicular through the pin of the fourth style is -45.84 and 34.38 degree. A theoretical simulation for rowing has been developed and presented. The results suggest that it may be advantageous for the rowers to select the sculling angles proper to sculling styles. The optimum sculling angles of the rower depends on the sculling styles made by each rower. The investigated of this paper can be concludes in three directions: 1;. There is the optimum sculling angle in arms only single scull of adaptive rowing. 2. The optimum sculling angles depend on the sculling styles. 3. Computer simulation of rowing can identify opportunities for improving rowing performance by utilizing the kinematic description of rowing. The freedom to explore alternatives in speed, thrust and timing with the computer simulation will provide the coach with a tool for systematic assessments of rowing technique In addition, the ability to use the computer to examine the very complex movements during rowing will help both the rower and the coach to conceptualize the components of movements that may have been previously unclear or even undefined.

Keywords: simulation, sculling, adaptive, rowing

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735 Correlation between Resistance to Non-Specific Inhibitor and Mammalian Pathogenicity of an Egg Adapted H9N2 Virus

Authors: Chung-Young Lee, Se-Hee Ahn, Jun-Gu Choi, Youn-Jeong Lee, Hyuk-Joon Kwon, Jae-Hong Kim

Abstract:

A/chicken/Korea/01310/2001 (H9N2) (01310) was passaged through embryonated chicken eggs (ECEs) by 20 times (01310-E20), and it has been used for an inactivated oil emulsion vaccine in Korea. After sequential passages, 01310-E20 showed higher pathogenicity in ECEs and acquired multiple mutations including a potential N-glycosylation at position 133 (H3 numbering) in HA and 18aa-deletion in NA stalk. To evaluate the effect of these mutations on the mammalian pathogenicity and resistance to non-specific inhibitors, we generated four PR8-derived recombinant viruses with different combinations of HA and NA from 01310-E2 and 01310-E20 (rH2N2, rH2N20, rH20N2, and rH20N20). According to our results, recombinant viruses containing 01310 E20 HA showed higher growth property in MDCK cells and higher virulence on mice than those containing 01310 E2 HA regardless of NA. The hemagglutination activity of rH20N20 was less inhibited by egg white and mouse lung extract than that of other recombinant viruses. Thus, the increased pathogenicity of 01310-E20 may be related to both higher replication efficiency and resistance to non-specific inhibitors in mice.

Keywords: avian influenza virus, egg adaptation, H9N2, N-glycosylation, stalk deletion of neuraminidase

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734 Cytotoxicity of a Short Chain Fatty Acid Histone Deactylase Inhibitor on HCT116 Human Colorectal Carcinoma Cell Line

Authors: N. A. Kazemi Sefat, M. M. Mohammadi, J. Hadjati, S. Talebi, M. Ajami, H. Daneshvar

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Colorectal cancer metastases result in a significant number of cancer related deaths. Histone deacetylase (HDAC) inhibitors induce growth arrest and apoptosis in a variety of human cancer cells. Sodium butyrate (SB) is a short chain fatty acid, belongs to HDAC inhibitors which is released in the colonic lumen as a consequence of fiber fermentation. In this study, we are about to assess the effect of sodium butyrate on HCT116 human colorectal carcinoma cell line. The viability of cells was measured by microscopic morphologic study and MTT assay. After 48 hours, treatments more than 10 mM lead to cell injury in HCT116 by increasing cell granulation and decreasing cell adhesion (p>0.05). After 72 hours, treatments at 10 mM and more lead to significant cell injury (p<0.05). Our results may suggest that the gene expression which is contributed in cell proliferation and apoptosis has been changed under pressure of HDAC inhibition.

Keywords: colorectal cancer, sodium butyrate, cytotoxicity, MTT

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733 Plastic Pellets in Santa Cruz Dos Navegantes Beach, Brazil, in the Winter of 2019

Authors: Victor Vasques Ribeiro

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The Santa Cruz dos Navegantes beach is located in the city of Guarujá, in the central portion of the coast of the state of São Paulo. Next to this beach is located the Channel of the Port of Santos, configured as a source of plastic pellets for marine environments. On sandy beaches near the sources, especially during the winter and after cold front entrance events, the amounts of pellets can be very high. This study aimed to determine the influence of a cold front entry event of the winter of 2019 on the amount of pellets found on Santa Cruz dos Navegantes beach, besides assuming the proximity of the sources. During six consecutive collection campaigns, three of which were previous and three after the cold front entry peak, 30.0 square meters of surface sediments were sampled in each campaign. The color and shape of the pellets were determined to assume the length of the permanence of these granules in the marine environment and, consequently, the proximity of the sources. This beach was considered ideal for this type of research. The pellet pollution index (PPI) was from moderate to very high right after the peak of the cold front entry. The cold front peak event significantly influenced the amount of pellets found on the beach of Santa Cruz dos Navegantes. The factors that can bury the pellets in the sediments were classified as low when compared to other beaches in the region. Most of the pellets found were recently produced and lost to aquatic environments. Like the other beaches near Santos Bay, Santa Cruz dos Navegantes beach receives significant amounts of pellets that have nearby origins. Therefore, it was supposed that the activities of the Santos port complex are sources of pellets for the marine environment. This pollution can be further worsened in certain meteoceanographic events. The beaches of this region need to be constantly monitored and evaluated for pollution by pellets.

Keywords: beach, cold front, pellets, sources

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732 Walnut (Juglans Regia) Extracts: Investigation of Antioxidant Effect, Total Phenols and Tyrosinase Inhibitory Activity

Authors: N. Saki, S. Nalbantoglu, M. Akin, G. Arabaci

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Walnut has a great range of phenolic profile and it is used in Asia and Africa for treatment of many diseases and cancer. Phenolic compounds play a number of crucial roles in complex metabolism of plants and of also fruit trees. Consumption of certain phenolics in the food is considered beneficial for human nutrition. Phenolic compounds known as anti-radical inactivators with their high antioxidant activities and these activities play an important role in inhibition of multi-metal corrosion. Many common corrosion inhibitors that are still in use today are health hazards. Therefore, there is still an increased attention directed towards the development of environmentally compatible, nonpolluting corrosion inhibitors. The present study reports the total phenols content, antioxidant potentials and tyrosinase inhibitory activity of the walnut (Juglans regia L.) produced in Turkey. The anti-tyrosinase activity was investigated for walnut at 2 h extraction time and all extracts exhibited tyrosinase activity. The results of this study suggested that walnut can be used as an excellent, easily accessible source of natural antioxidant.

Keywords: antioxidant activity, Juglans Regia, total phenols, tyrosinase activity

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731 Development of International Entry-Level Nursing Competencies to Address the Continuum of Substance Use

Authors: Cheyenne Johnson, Samantha Robinson, Christina Chant, Ann M. Mitchell, Carol Price, Carmel Clancy, Adam Searby, Deborah S. Finnell

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Introduction: Substance use along the continuum from at-risk use to a substance use disorder (SUD) contributes substantially to the burden of disease and related harms worldwide. There is a growing body of literature that highlights the lack of substance use related content in nursing curricula. Furthermore, there is also a lack of consensus on key competencies necessary for entry-level nurses. Globally, there is a lack of established nursing competencies related to prevention, health promotion, harm reduction and treatment of at-risk substance use and SUDs. At a critical time in public health, this gap in nursing curricula contributes to a lack of preparation for entry-level nurses to support people along the continuum of substance use. Thus, in practice, early opportunities for screening, support, and interventions may be missed. To address this gap, an international committee was convened to develop international entry-level nursing competencies specifying the knowledge, skills, and abilities that all nurses should possess in order to address the continuum of substance use. Methodology: An international steering committee, including representation from Canada, United States, United Kingdom, and Australia was established to lead this work over a one-year time period. The steering committee conducted a scoping review, undertaken to examine nursing competency frameworks, and to inform a competency structure that would guide this work. The next steps were to outline key competency areas and establish leaders for working groups to develop the competencies. In addition, a larger international committee was gathered to contribute to competency working groups, review the collective work and concur on the final document. Findings: A comprehensive framework was developed with competencies covering a wide spectrum of substance use across the lifespan and in the context of prevention, health promotion, harm reduction and treatment, including special populations. The development of this competency-based framework meets an identified need to provide guidance for universities, health authorities, policy makers, nursing regulators and other organizations that provide and support nursing education which focuses on care for patients and families with at-risk substance use and SUDs. Conclusion: Utilizing these global competencies as expected outcomes of an educational and skill building curricula for entry-level nurses holds great promise for incorporating evidence-informed training in the care and management of people across the continuum of substance use.

Keywords: addiction nursing, addiction nursing curriculum, competencies, substance use

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730 Synthesis, Inhibitory Activity, and Molecular Modelling of 2-Hydroxy-3-Oxo-3-Phenylpropionate Derivatives as HIV-1-Integrase Inhibitors

Authors: O. J. Jesumoroti, Faridoon, R. Klein, K. A. Iobb, D. Mnkadhla, H. C. Hoppe, P. T. Kaye

Abstract:

The 1, 3-aryl diketo acids (DKA) based agents represent an important class of HIV integrase (IN) strand transfer inhibitors. In other to study the chelating role of the divalent metal ion in the inhibition of IN strand transfer, we designed and synthesized a series of 2-hydroxy-3-oxo-3-phenyl propionate derivatives with the notion that such compounds could interact with the divalent ion in the active site of IN. The synthetic sequence to the desired compounds involves the concept of Doebner knoevenagel condensation, Fischer esterification and ketohydroxylation using neuclophilic re-oxidant; compounds were characterized by their IR, IHNMR, 13CNMR, HRMS spectroscopic data and melting point determination. Also, molecular docking was employed in this study and it was revealed that there is interaction with the active site of the enzyme. However, there is disparity in the corresponding anti-HIV activity determined by the experimental bioassay. These compounds lack potency at low micromolar concentration when compared to the results of the docking studies. Nevertheless, the results of the study suggest modification of the aryl ring with one or two hydroxyl groups to improve the inhibitory activity.

Keywords: anti-HIV-1 integrase, ketohydroxylation, molecular docking, propionate derivatives

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729 Cannabis Sativa L as Natural Source of Promising Anti-Alzheimer Drug Candidates: A Comprehensive Computational Approach Including Molecular Docking, Molecular Dynamics, Admet and MM-PBSA Studies

Authors: Hassan Nour, Nouh Mounadi, Oussama Abchir, Belaidi Salah, Samir Chtita

Abstract:

Cholinesterase enzymes are biological catalysts essential for the transformation of acetylcholine, which is a neurotransmitter implicated in memory and learning, into acetic acid and choline, altering the neurotransmission process in Alzheimer’s disease patients. Therefore, inhibition of cholinesterase enzymes is a relevant strategy for the symptomatic treatment of Alzheimer’s disease. The current investigation aims to explore potential Cholinesterase (ChE) inhibitors through a comprehensive computational approach. Forty-nine phytoconstituents extracted from Cannabis sativa L were in-silico screened using molecular docking, pharmacokinetic and toxicological analysis to evaluate their possible inhibitory effect towards the cholinesterase enzymes. Two phytoconstituents belonging to cannabinoid derivatives were revealed to be promising candidates for Alzheimer therapy by acting as cholinesterase inhibitors. They have exhibited high binding affinities towards the cholinesterase enzymes and showed their ability to interact with key residues involved in cholinesterase enzymatic activity. In addition, they presented good ADMET profiles allowing them to be promising oral drug candidates. Furthermore, molecular dynamics (MD) simulations were executed to explore their interactions stability under mimetic biological conditions and thus support our findings. To corroborate the docking results, the binding free energy corresponding to the more stable ligand-ChE complexes was re-estimated by applying the MM-PBSA method. MD and MM-PBSA studies affirmed that the ligand-ChE recognition is spontaneous reaction leading to stable complexes. The conducted investigations have led to great findings that would strongly guide the pharmaceutical industries towards the rational development of potent anti-Alzheimer agents.

Keywords: alzheimer’s disease, molecular docking, cannabis sativa l, cholinesterase inhibitors

Procedia PDF Downloads 48
728 Study of the Efficacy of Cysteine Protease Inhibitors Alone or Combined with Praziquantel as Chemotherapy for Mice Schistosomiasis mansoni

Authors: Alyaa Ahmed Farid, Aida Ismail, Ibrahim Rabia, Azza Fahmy, Azza El Amir

Abstract:

This study was designed for assessment of 3 types of Cysteine protease inhibitors (CPIs) fluromethylketone (FMK), vinyl sulfone (VS) and sodium nitro prussid (SNP), to define which of them is the best? The experiments aimed to define the protective power of each inhibitor alone or combined with PZQ for curing S. mansoni infection in mice. In vitro, treated S. mansoni adult worms recorded a mortality rate after 1 hr of exposure to 500 ppm of FMK, VS and SNP as 75, 70 and 60%, while, treated cercaria recorded 75, 60 and 50%, respectively. FMK+PZQ treatment recorded the maximum reduction in worm burden (97.2% at 5 wk PI). VS treatment alone or combined with PZQ increases IgM, total IgG, IgG2 and IgG4 levels. In EM study of worm tegument, while only detachment of spines was observed in PZQ treated group, the completely implanted spines were reported in the degenerated tegument of adult worms in all groups treated with CPIs. Treatment with VS+PZQ increased Igs levels but, its effect was different on worm reduction. So, it is not enough to eliminate the infection and FMK+PZQ considered the antischistosomicidal drug of choice.

Keywords: praziquantel, fluromethylketone, vinyl sulfone, worm burden, immunoglobulin pattern

Procedia PDF Downloads 343
727 Prevalence of Pretreatment Drug HIV-1 Mutations in Moscow, Russia

Authors: Daria Zabolotnaya, Svetlana Degtyareva, Veronika Kanestri, Danila Konnov

Abstract:

An adequate choice of the initial antiretroviral treatment determines the treatment efficacy. In the clinical guidelines in Russia non-nucleoside reverse transcriptase inhibitors (NNRTIs) are still considered to be an option for first-line treatment while pretreatment drug resistance (PDR) testing is not routinely performed. We conducted a cohort retrospective study in HIV-positive treatment naïve patients of the H-clinic (Moscow, Russia) who performed PDR testing from July 2017 to November 2021. All the information was obtained from the medical records anonymously. We analyzed the mutations in reverse transcriptase and protease genes. RT-sequences were obtained by AmpliSens HIV-Resist-Seq kit. Drug resistance was defined using the HIVdb Program v. 8.9-1. PDR was estimated using the Stanford algorithm. Descriptive statistics were performed in Excel (Microsoft Office, 2019). A total of 261 HIV-1 infected patients were enrolled in the study including 197 (75.5%) male and 64 (24.5%) female. The mean age was 34.6±8.3 years. The median CD4 count – 521 cells/µl (IQR 367-687 cells/µl). Data on risk factors of HIV-infection were scarce. The total quantity of strains containing mutations in the reverse transcriptase gene was 75 (28.7%). From these 5 (1.9%) mutations were associated with PDR to nucleoside reverse transcriptase inhibitors (NRTIs) and 30 (11.5%) – with PDR to NNRTIs. The number of strains with mutations in protease gene was 43 (16.5%), from these only 3 (1.1%) mutations were associated with resistance to protease inhibitors. For NNRTIs the most prevalent PDR mutations were E138A, V106I. Most of the HIV variants exhibited a single PDR mutation, 2 were found in 3 samples. Most of HIV variants with PDR mutation displayed a single drug class resistance mutation. 2/37 (5.4%) strains had both NRTIs and NNRTIs mutations. There were no strains identified with PDR mutations to all three drug classes. Though earlier data demonstrated a lower level of PDR in HIV treatment naïve population in Russia and our cohort can be not fully representative as it is taken from the private clinic, it reflects the trend of increasing PDR especially to NNRTIs. Therefore, we consider either pretreatment testing or giving the priority to other drugs as first-line treatment necessary.

Keywords: HIV, resistance, mutations, treatment

Procedia PDF Downloads 71
726 Aptamers: A Potential Strategy for COVID-19 Treatment

Authors: Mohamad Ammar Ayass, Natalya Griko, Victor Pashkov, Wanying Cao, Kevin Zhu, Jin Zhang, Lina Abi Mosleh

Abstract:

Respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent for coronavirus disease 2019 (COVID-19). Early evidence pointed at the angiotensin-converting enzyme 2 (ACE-2) expressed on the epithelial cells of the lung as the main entry point of SARS-CoV-2 into the cells. The viral entry is mediated by the binding of the Receptor Binding Domain (RBD) of the spike protein that is expressed on the surface of the virus to the ACE-2 receptor. As the number of SARS-CoV-2 variants continues to increase, mutations arising in the RBD of SARS-CoV-2 may lead to the ineffectiveness of RBD targeted neutralizing antibodies. To address this limitation, the objective of this study is to develop a combination of aptamers that target different regions of the RBD, preventing the binding of the spike protein to ACE-2 receptor and subsequent viral entry and replication. A safe and innovative biomedical tool was developed to inhibit viral infection and reduce the harms of COVID-19. In the present study, DNA aptamers were developed against a recombinant trimer S protein using the Systematic Evolution of Ligands by Exponential enrichment (SELEX). Negative selection was introduced at round number 7 to select for aptamers that bind specifically to the RBD domain. A series of 9 aptamers (ADI2010, ADI2011, ADI201L, ADI203L, ADI205L, ADIR68, ADIR74, ADIR80, ADIR83) were selected and characterized with high binding affinity and specificity to the RBD of the spike protein. Aptamers (ADI25, ADI2009, ADI203L) were able to bind and pull down endogenous spike protein expressed on the surface of SARS-CoV-2 virus in COVID-19 positive patient samples and determined by liquid chromatography- tandem mass spectrometry analysis (LC-MS/MS). LC-MS/MS data confirmed that aptamers can bind to the RBD of the spike protein. Furthermore, results indicated that the combination of the 9 best aptamers inhibited the binding of the purified trimer spike protein to the ACE-2 receptor found on the surface of Vero E6 cells. In the same experiment, the combined aptamers displayed a better neutralizing effect than antibodies. The data suggests that the selected aptamers could be used in therapy to neutralize the effect of the SARS-CoV-2 virus by inhibiting the interaction between the RBD and ACE-2 receptor, preventing viral entry into target cells and therefore blocking viral replication.

Keywords: aptamer, ACE-2 receptor, binding inhibitor, COVID-19, spike protein, SARS-CoV-2, treatment

Procedia PDF Downloads 169
725 Inhibition of Crystallization Lithiasis Phosphate (Struvite) by Extracts Zea mays

Authors: N. Benahmed, A. Cheriti

Abstract:

Kidney stones of infectious origin, in particular, the phosphate amoniaco-magnesian hexahydrate or struvite are one of the risk factors that most often leads of renal insufficiency. Many plants species, described in pharmacopoeias of several countries is used as a remedy for urinary stones, the latter is a disease resulting from the presence of stones in the kidneys or urinary tract. Our research is based on the existing relationship between the effect of extracts of medicinal plant used for the cure of urinary tract diseases in the region of Algeria south-west on urolithiasis especially Ammonium-Magnesium Phosphate Hexahydrate (Struvite). We have selected Zea mays L. (POACEAE) for this study. On the first stage, we have studied the crystallisation of struvite 'in vitro' without inhibitors, after we have compared to crystallization with inhibitors. Most of The organic and aqueous extracts of this plant give an effect on the crystal size of struvite. It is a very significant reduction in the size of the crystals of struvite in the presence of hexane and ethanol extract (12 to 5-6 μm). We’ve observed a decrease in the size of the aggregates in the presence of all the extracts. This reduction is important for the aqueous, acetone and chloroform extract (45 to 10-16μm). Finally, a deep study was conducted on the effective extract of Zea mays L.; for determine the influence of inhibitory phytochemical compounds.

Keywords: medicinal plants, struvite, urolithiasis, zea mays

Procedia PDF Downloads 421
724 Cannabis Sativa L as Natural Source of Promising Anti-Alzheimer Drug Candidates: A Comprehensive Computational Approach Including Molecular Docking, Molecular Dynamics, ADMET and MM-PBSA Studies

Authors: Hassan Nour, Nouh Mounadi, Oussama Abchir, Belaidi Salah, Samir Chtita

Abstract:

Cholinesterase enzymes are biological catalysts essential for the transformation of acetylcholine, which is a neurotransmitter implicated in memory and learning, into acetic acid and choline, altering the neurotransmission process in Alzheimer’s disease patients. Therefore, inhibition of cholinesterase enzymes is a relevant strategy for the symptomatic treatment of Alzheimer’s disease. The current investigation aims to explore potential cholinesterase (ChE) inhibitors through a comprehensive computational approach. Forty-nine phytoconstituents extracted from Cannabis sativa L. were in-silico screened using molecular docking and pharmacokinetic and toxicological analysis to evaluate their possible inhibitory effect on the cholinesterase enzymes. Two phytoconstituents belonging to cannabinoid derivatives were revealed to be promising candidates for Alzheimer's therapy by acting as cholinesterase inhibitors. They have exhibited high binding affinities towards the cholinesterase enzymes and showed their ability to interact with key residues involved in cholinesterase enzymatic activity. In addition, they presented good ADMET profiles allowing them to be promising oral drug candidates. Furthermore, molecular dynamics (MD) simulations were executed to explore their interaction stability under mimetic biological conditions and thus support our findings. To corroborate the docking results, the binding free energy corresponding to the more stable ligand-ChE complexes was re-estimated by applying the MM-PBSA method. MD and MM-PBSA studies affirmed that the ligand-ChE recognition is a spontaneous reaction leading to stable complexes. The conducted investigations have led to great findings that would strongly guide the pharmaceutical industries toward the rational development of potent anti-Alzheimer agents.

Keywords: Alzheimer’s disease, molecular docking, Cannabis sativa L., cholinesterase inhibitors, molecular dynamics, ADMET, MM-PBSA

Procedia PDF Downloads 59
723 Barriers to Entry: The Pitfall of Charter School Accountability

Authors: Ian Kingsbury

Abstract:

The rapid expansion of charter schools (public schools that receive government but do not face the same regulations as traditional public schools) over the preceding two decades has raised concerns over the potential for graft and fraud. These concerns are largely justified: Incidents of financial crime and mismanagement are not unheard of, and the charter sector has become a darling of hedge fund managers. In response, several states have strengthened their charter school regulatory regimes. Imposing regulations and attempting to increase accountability seem like sensible measures, and perhaps they are necessary. However, increased regulation may come at the cost of imposing barriers to entry. Specifically, increased regulation often entails evidence for a high likelihood of fiscal solvency. That should theoretically entail access to capital in the short-term, which may systematically preclude Black or Hispanic applicants from opening charter schools. Moreover, increased regulation necessarily entails more red tape. The institutional wherewithal and the number of hours required to complete an application to open a charter school might favor those who have partnered with an education service provider, specifically a charter management organization (CMO) or education management organization (EMO). These potential barriers to entry pose a significant policy concern. Just as policymakers hope to increase the share of minority teachers and principals, they should sensibly care whether individuals who open charter schools look like the students in that school. Moreover, they might be concerned if successful applications in states with stringent regulations are overwhelmingly affiliated with education service providers. One of the original missions of charter schools was to serve as a laboratory of innovation. Approving only those applications affiliated with education service providers (and in effect establishing a parallel network of schools rather than a diverse marketplace of schools) undermines that mission. Data and methods: The analysis examines more than 2,000 charter school applications from 15 states. It compares the outcomes of applications from states with a strong regulatory environment (those with high scores) from NACSA-the National Association of Charter School Authorizers- to applications from states with a weak regulatory environment (those with a low NACSA score). If the hypothesis is correct, applicants not affiliated with an ESP are more likely to be rejected in high-regulation states compared to those affiliated with an ESP, and minority candidates not affiliated with an education service provider (ESP) are particularly likely to be rejected. Initial returns indicate that the hypothesis holds. More applications in low NASCA-scoring Arizona come from individuals not associated with an ESP, and those individuals are as likely to be accepted as those affiliated with an ESP. On the other hand, applicants in high-NACSA scoring Indiana and Ohio are more than 20 percentage points more likely to be accepted if they are affiliated with an ESP, and the effect is particularly pronounced for minority candidates. These findings should spur policymakers to consider the drawbacks of charter school accountability and consider accountability regimes that do not impose barriers to entry.

Keywords: accountability, barriers to entry, charter schools, choice

Procedia PDF Downloads 126
722 Human Par14 and Par17 Isomerases Bind Hepatitis B Virus Components Inside and Out

Authors: Umar Saeed

Abstract:

Peptidyl-prolyl cis/trans isomerases Par14 and Par17 in humans play crucial roles in diverse cellular processes, including protein folding, chromatin remodeling, DNA binding, ribosome biogenesis, and cell cycle progression. However, the effects of Par14 and Par17 on viral replication have been explored to a limited extent. We first time discovered their influential roles in promoting Hepatitis B Virus replication. In this study, we observed that in the presence of HBx, either Par14 or Par17 could upregulate HBV replication. However, in the absence of HBx, neither Par14 nor Par17 had any effect on replication. Their mechanism of action involves binding to specific motifs within HBc and HBx proteins. Notably, they target the conserved 133Arg-Pro134 (RP) motif of HBc and the 19RP20-28RP29 motifs of HBx. This interaction is fundamental for the stability of HBx, core particles, and HBc. Par14 and Par17 exhibit versatility by binding both outside and inside core particles, thereby facilitating core particle assembly through their participation in HBc dimer-dimer interactions. NAGE and immunoblotting analyses unveiled the binding of Par14/Par17 to core particles. Co-immunoprecipitation experiments further demonstrated the interaction of Par14/Par17 with core particle assembly-defective and dimer-positive HBc-Y132A. It's essential to emphasize that R133 is the key residue in the HBc RP motif that governs their interaction with Par14/Par17. Chromatin immunoprecipitation conducted on HBV-infected cells elucidated the participation of residues S19 and E46/D74 in Par14 and S44 and E71/D99 in Par17 in the recruitment of 133RP134 motif-containing HBc into cccDNA. Depleting PIN4 in liver cell lines results in a significant reduction in cccDNA levels, pgRNA, sgRNAs, HBc, core particle assembly, and HBV DNA synthesis. Notably, parvulin inhibitors like juglone and PiB have proven to be effective in substantially reducing HBV replication. These inhibitors weaken the interaction between HBV core particles and Par14/Par17, underscoring the dynamic nature of this interaction. It's also worth noting that specific Par14/Par17 inhibitors hold promise as potential therapeutic options for chronic hepatitis B.

Keywords: Par14Par17, HBx, HBc, cccDNA, HBV

Procedia PDF Downloads 37
721 Electrochemical and Theoretical Quantum Approaches on the Inhibition of C1018 Carbon Steel Corrosion in Acidic Medium Containing Chloride Using Newly Synthesized Phenolic Schiff Bases Compounds

Authors: Hany M. Abd El-Lateef

Abstract:

Two novel Schiff bases, 5-bromo-2-[(E)-(pyridin-3-ylimino) methyl] phenol (HBSAP) and 5-bromo-2-[(E)-(quinolin-8-ylimino) methyl] phenol (HBSAQ) have been synthesized. They have been characterized by elemental analysis and spectroscopic techniques (UV–Vis, IR and NMR). Moreover, the molecular structure of HBSAP and HBSAQ compounds are determined by single crystal X-ray diffraction technique. The inhibition activity of HBSAP and HBSAQ for carbon steel in 3.5 %NaCl+0.1 M HCl for both short and long immersion time, at different temperatures (20-50 ºC), was investigated using electrochemistry and surface characterization. The potentiodynamic polarization shows that the inhibitors molecule is more adsorbed on the cathodic sites. Its efficiency increases with increasing inhibitor concentrations (92.8 % at the optimal concentration of 10-3 M for HBSAQ). Adsorption of the inhibitors on the carbon steel surface was found to obey Langmuir’s adsorption isotherm with physical/chemical nature of the adsorption, as it is shown also by scanning electron microscopy. Further, the electronic structural calculations using quantum chemical methods were found to be in a good agreement with the results of the experimental studies.

Keywords: carbon steel, Schiff bases, corrosion inhibition, SEM, electrochemical techniques

Procedia PDF Downloads 365
720 Material Properties Evolution Affecting Demisability for Space Debris Mitigation

Authors: Chetan Mahawar, Sarath Chandran, Sridhar Panigrahi, V. P. Shaji

Abstract:

The ever-growing advancement in space exploration has led to an alarming concern for space debris removal as it restricts further launch operations and adventurous space missions; hence numerous studies have come up with technologies for re-entry predictions and material selection processes for mitigating space debris. The selection of material and operating conditions is determined with the objective of lightweight structure and ability to demise faster subject to spacecraft survivability during its mission. Since the demisability of spacecraft depends on evolving thermal material properties such as emissivity, specific heat capacity, thermal conductivity, radiation intensity, etc. Therefore, this paper presents the analysis of evolving thermal material properties of spacecraft, which affect the demisability process and thus estimate demise time using the demisability model by incorporating evolving thermal properties for sensible heating followed by the complete or partial break-up of spacecraft. The demisability analysis thus concludes the best suitable spacecraft material is based on the least estimated demise time, which fulfills the criteria of design-for-survivability and as well as of design-for-demisability.

Keywords: demisability, emissivity, lightweight, re-entry, survivability

Procedia PDF Downloads 90
719 Discovery, Design and Synthesis of Some Novel Antitumor 1,2,4-Triazine Derivatives as C-Met Kinase Inhibitors

Authors: Ibrahim M. Labouta, Marwa H. El-Wakil, Hayam M. Ashour, Ahmed M. Hassan, Manal N. Saudi

Abstract:

The receptor tyrosine kinase c-Met is an attractive target for therapeutic treatment of cancers nowadays. Among the wide variety of heterocycles that have been explored for developing c-Met kinase inhibitors, the 1,2,4-triazines have been rarely investigated, although they are well known in the literature to possess antitumor activities. Herein we describe the design and synthesis of a novel series of 1,2,4-triazine derivatives possessing N-acylarylhydrazone moiety and another series combining the 1,2,4-triazine scaffold to the well-known anticancer drug 6-MP in order to explore their “double-drug” effect. The synthesized compounds were evaluated for their in vitro antitumor activity against three c-Met addicted cancer cell lines (A549, HT-29 and MKN-45). Most compounds showed moderate to excellent antiproliferative activity and four compounds showed potent inhibitory activity more than the reference drug Foretinib against one or more cancer cell lines. The obtained results revealed that the potent compounds are highly selective to A549 (lung adenocarcinoma) cancer cell line. The c-Met kinase inhibitory activity of the potent derivatives is still under investigation. The present study clearly demonstrates that the 1,2,4-triazine core ring exhibits promising antitumor activity with potential c-Met kinase inhibitory activity.

Keywords: 1, 2, 4-triazine, antitumor, c-Met inhibitor, double-drug

Procedia PDF Downloads 319
718 Synthesis and Biological Evaluation of Some Benzoxazole Derivatives as Inhibitors of Acetylcholinesterase / Butyrylcholinesterase and Tyrosinase

Authors: Ozlem Temiz-Arpaci, Meryem Tasci, Fatma Sezer Senol, İlkay Erdogan Orhan

Abstract:

Alzheimer’s disease (AD), a neurodegenerative disorder characterized by a progressive deterioration of memory and cognition, occurs more frequently in elderly people. Current treatment approaches in this disease with the major therapeutic strategy are based on the AChE and BChE inhibition. On the other hand, tyrosinase inhibition has become a target for the treatment of Parkinson’s disease (PD) since this enzyme may play a role in neuromelanin formation in the human brain and could be critical in the formation of dopamine neurotoxicity associated with neurodegeneration linked to PD. Also benzoxazoles are structural isosteres of natural nucleotides that can interact with biopolymers so that benzoxazoles showed a lot of different biological activities. In this study, a series of 2,5-disubstituted-benzoxazole derivatives were synthesized and were evaluated as possible inhibitors of acetylcholinesterase (AChE) / butyrylcholinesterase (BChE) and tyrosinase. The results demonstrated that the compounds exhibited a weak spectrum of AChE / BChE inhibitory activity ranging between 3.92% - 54.32% except compound 8 which showed no activity against AChE and compound 4 which showed no activity against BChE at the specified molar concentrations. Also, the compounds indicated lower than tyrosinase inhibitory activity of ranging between 8.14% - 22.90% to that of reference (kojic acid).

Keywords: AChE and BChE inhibition, Alzheimer’s disease, benzoxazoles, tyrosinase inhibition

Procedia PDF Downloads 313