266 research outputs found

    0E2FA: Zero Effort Two-Factor Authentication

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    Smart devices (mobile devices, laptops, tablets, etc.) can receive signals from different radio frequency devices that are within range. As these devices move between networks (e.g., Wi-Fi hotspots, cellphone towers, etc.), they receive broadcast messages from access points, some of which can be used to collect useful information. This information can be utilized in a variety of ways, such as to establish a connection, to share information, to locate devices, and to identify users, which is central to this dissertation. The principal benefit of a broadcast message is that smart devices can read and process the embedded information without first being connected to the corresponding network. Moreover, broadcast messages can be received only within the range of the wireless access point that sends the broadcast, thus inherently limiting access to only those devices in close physical proximity, which may facilitate many applications that are dependent on proximity. In our research, we utilize data contained in these broadcast messages to implement a two-factor authentication (2FA) system that, unlike existing methods, does not require any extra effort on the part of the users of the system. By determining if two devices are in the same physical location and sufficiently close to each other, we can ensure that they belong to the same user. This system depends on something that a user knows, something that a user owns, and—a significant contribution of this work—something that is in the user’s environment

    Secure Mobile Payment Architecture Enabling Multi-factor Authentication

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    The rise of smartphones has led to a significant increase in the usage of mobile payments. Mobile payments allow individuals to access financial resources and make transactions through their mobile devices while on the go. However, the current mobile payment systems were designed to align with traditional payment structures, which limits the full potential of smartphones, including their security features. This has become a major concern in the rapidly growing mobile payment market. To address these security concerns,in this paper we propose new mobile payment architecture. This architecture leverages the advanced capabilities of modern smartphones to verify various aspects of a payment, such as funds, biometrics, location, and others. The proposed system aims to guarantee the legitimacy of transactions and protect against identity theft by verifying multiple elements of a payment. The security of mobile payment systems is crucial, given the rapid growth of the market. Evaluating mobile payment systems based on their authentication, encryption, and fraud detection capabilities is of utmost importance. The proposed architecture provides a secure mobile payment solution that enhances the overall payment experience by taking advantage of the advanced capabilities of modern smartphones. This will not only improve the security of mobile payments but also offer a more user-friendly payment experience for consumers

    Alpha-amylase and alpha-glucosidase enzyme inhibition and antioxidant potential of 3-oxolupenal and katononic acid isolated from Nuxia oppositifolia

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    Nuxia oppositifolia is traditionally used in diabetes treatment in many Arabian countries; however, scientific evidence is lacking. Hence, the present study explored the antidiabetic and antioxidant activities of the plant extracts and their purified compounds. The methanolic crude extract of N. oppositifolia was partitioned using a two-solvent system. The n-hexane fraction was purified by silica gel column chromatography to yield several compounds including katononic acid and 3-oxolupenal. Antidiabetic activities were assessed by α-amylase and α-glucosidase enzyme inhibition. Antioxidant capacities were examined by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2â€Č-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) scavenging assays. Further, the interaction between enzymes (α-amylase and α-glucosidase) and ligands (3-oxolupenal and katononic acid) was followed by fluorescence quenching and molecular docking studies. 3-oxolupenal and katononic acid showed IC50 values of 46.2 ”g/mL (101.6 ”M) and 52.4 ”g/mL (119.3 ”M), respectively against the amylase inhibition. 3-oxolupenal (62.3 ”g/mL or 141.9 ”M) exhibited more potent inhibition against α-glucosidases compared to katononic acid (88.6 ”g/mL or 194.8 ”M). In terms of antioxidant activity, the relatively polar crude extract and n-butanol fraction showed the greatest DPPH and ABTS scavenging activity. However, the antioxidant activities of the purified compounds were in the low to moderate range. Molecular docking studies confirmed that 3-oxolupenal and katononic acid interacted strongly with the active site residues of both α-amylase and α-glucosidase. Fluorescence quenching results also suggest that 3-oxolupenal and katononic acid have a good affinity towards both α-amylase and α-glucosidase enzymes. This study provides preliminary data for the plant’s use in the treatment of type 2 diabetes mellitus

    Acute Appendicitis among Saudi and Non-Saudi Patients: A Cross-Sectional Based Study

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    Objective: We conduct this study to discuss the differences between Saudi and non- Saudi patients with acute appendicitis.Background: Acute appendicitis is one of emergency surgeries in developing and developed countries. Its symptoms are vomiting, lower abdominal pain and decreased appetite. Appendicitis needs urgent surgical prouder to avoid its perforation and associated complications which may lead to death. Method: We conduct cross-sectional based study in one of khamis Mushayt, Saudi Araba. 136 patients diagnosed with acute appendicitis were included and their medical records were reviewed after getting their informed consent.Results: We included 136 patients, 90 were non-Saudi and 46 were Saudi. There were no statistically differences in their diagnosis but the distribution of the diagnosis was different.Conclusion: Acute appendicitis was more prevalent among non-Saudi patients, the diagnosis between both was with no significant differences. Keywords: acute appendicitis, Saudi, non-Saudi, diagnosis, cross-sectional, Saudi Arabia and khamis Mushayt

    Attenuation of methylglyoxal-induced glycation and cellular dysfunction in wound healing by Centella cordifolia

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    Current pre-clinical evidences of Centella focus on its pharmacological effects on normal wound healing but there are limited studies on the bioactivity of Centella in cellular dysfunction associated with diabetic wounds. Hence we planned to examine the potential of Centella cordifolia in inhibiting methylglyoxal (MGO)-induced extracellular matrix (ECM) glycation and promoting the related cellular functions. A Cell-ECM adhesion assay examined the ECM glycation induced by MGO. Different cell types that contribute to the healing process (fibroblasts, keratinocytes and endothelial cells) were evaluated for their ability to adhere to the glycated ECM. Methanolic extract of Centella species was prepared and partitioned to yield different solvent fractions which were further analysed by high performance liquid chromatography equipped with photodiode array detector (HPLC-PDA) method. Based on the antioxidant [2,2-diphenyl-1-picrylhydrazyl (DPPH) assay] screening, anti-glycation activity and total phenolic content (TPC) of the different Centella species and fractions, the ethyl acetate fraction of C. cordifolia was selected for further investigating its ability to inhibit MGO-induced ECM glycation and promote cellular distribution and adhesion. Out of the three Centella species (C. asiatica, C. cordifolia and C. erecta), the methanolic extract of C. cordifolia showed maximum inhibition of Advanced glycation end products (AGE) fluorescence (20.20 ± 4.69 %, 25.00 ± 3.58 % and 16.18 ± 1.40 %, respectively). Its ethyl acetate fraction was enriched with phenolic compounds (3.91 ± 0.12 mg CAE/ÎŒg fraction) and showed strong antioxidant (59.95 ± 7.18 ÎŒM TE/ÎŒg fraction) and antiglycation activities. Improvement of cells spreading and adhesion of endothelial cells, fibroblasts and keratinocytes was observed for ethyl acetate treated MGO-glycated extracellular matrix. Significant reduction in attachment capacity of EA.hy926 cells seeded on MGO-glycated fibronectin (41.2%) and attachment reduction of NIH3t3 and HaCaT cells seeded on MGO-glycated collagen (33.7% and 24.1%, respectively) were observed. Our findings demonstrate that ethyl acetate fraction of C. cordifolia was effective in attenuating MGO-induced glycation and cellular dysfunction in the in-vitro wound healing models suggesting that C. cordifolia could be a potential candidate for diabetic wound healing. It could be subjected for further isolation of new phytoconstituents having potential diabetic wound healing properties

    A Phytochemical Analysis, Microbial Evaluation and Molecular Interaction of Major Compounds of Centaurea bruguieriana Using HPLC-Spectrophotometric Analysis and Molecular Docking

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    Centaurea is one of the most important genera within the family Asteraceae. An investigation of the phytochemical composition of Centaurea bruguieriana using Gas-Chromatography coupled to Mass spectrometry (GC-MS) was performed. Antimicrobial activity was evaluated using the minimum inhibitory concentration method (MIC) and validated by molecular docking for the major compounds of the most active fraction (1,10-di-epi-cubenol and methyl 8-oxooctanoate) of C. bruguieriana against three bacterial receptors (TyrRS, DNA gyrase, and dihydrofolate reductase (DHFR)). Evaluation of antioxidant activity was conducted using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2â€Č-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. High-performance liquid chromatography (HPLC) was used to identify and quantify the contents of major compounds from ethyl acetate fraction (luteolin 7-O-glucoside, chlorogenic acid, kaempferol and isorhamnetin). The antimicrobial activity test showed that the chloroform fraction was more active against all microbial strains. The results of the molecular docking of two major compounds from chloroform fraction showed that good affinities were made between 1,10-di-epi-cubenol and the three selected receptors (TyrRs: −6.0 Kcal/mol against −8.2 Kcal/mol obtained with clorobiocin (standard); DNA gyrase: −6.6 Kcal/mol against −9.1 Kcal/mole obtained with clorobiocin; DHFR: −7.4 Kcal/mol against −6.3 Kcal/mol obtained with SCHEMBL2181345 Standard). Antioxidant evaluation showed that the ethyl acetate fraction was the most active fraction in DPPH (IC50 49.4 ”g/mL) and ABTS (IC50 52.8 ”g/mL) models. HPLC results showed the contents of luteolin 7-O-glucoside (7.4 ”g/mg), and chlorogenic acid (3.2 ”g/mg). Our study demonstrated that C. bruguierana is a promising source of bioactive compounds

    A Phytochemical Analysis, Microbial Evaluation and Molecular Interaction of Major Compounds of Centaurea bruguieriana Using HPLC-Spectrophotometric Analysis and Molecular Docking

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    Centaurea is one of the most important genera within the family Asteraceae. An investigation of the phytochemical composition of Centaurea bruguieriana using Gas-Chromatography coupled to Mass spectrometry (GC-MS) was performed. Antimicrobial activity was evaluated using the minimum inhibitory concentration method (MIC) and validated by molecular docking for the major compounds of the most active fraction (1,10-di-epi-cubenol and methyl 8-oxooctanoate) of C. bruguieriana against three bacterial receptors (TyrRS, DNA gyrase, and dihydrofolate reductase (DHFR)). Evaluation of antioxidant activity was conducted using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2â€Č-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) assays. High-performance liquid chromatography (HPLC) was used to identify and quantify the contents of major compounds from ethyl acetate fraction (luteolin 7-O-glucoside, chlorogenic acid, kaempferol and isorhamnetin). The antimicrobial activity test showed that the chloroform fraction was more active against all microbial strains. The results of the molecular docking of two major compounds from chloroform fraction showed that good affinities were made between 1,10-di-epi-cubenol and the three selected receptors (TyrRs: −6.0 Kcal/mol against −8.2 Kcal/mol obtained with clorobiocin (standard); DNA gyrase: −6.6 Kcal/mol against −9.1 Kcal/mole obtained with clorobiocin; DHFR: −7.4 Kcal/mol against −6.3 Kcal/mol obtained with SCHEMBL2181345 Standard). Antioxidant evaluation showed that the ethyl acetate fraction was the most active fraction in DPPH (IC50 49.4 ”g/mL) and ABTS (IC50 52.8 ”g/mL) models. HPLC results showed the contents of luteolin 7-O-glucoside (7.4 ”g/mg), and chlorogenic acid (3.2 ”g/mg). Our study demonstrated that C. bruguierana is a promising source of bioactive compounds

    Anti-inflammatory and anti-oxidant properties of Ipomoea nil (Linn.) Roth significantly alleviates cigarette smoke (CS)-induced acute lung injury via possibly inhibiting the NF-KB pathway

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    Acute respiratory distress syndrome (ARDS), a serious manifestation of acute lung injury (ALI), is a debilitating inflammatory lung disease that is caused by multiple risk factors. One of the primary causes that can lead to ALI/ ARDS is cigarette smoke (CS) and its primary mode of action is via oxidative stress. Despite extensive research, no appropriate therapy is currently available to treat ALI/ARDS, which means there is a dire need for new potential approaches. In our study we explored the protective effects of 70 % methanolic-aqueous extract of Ipomoea nil (Linn.) Roth, named as In.Mcx against CS-induced ALI mice models and RAW 264.7 macrophages because Ipomoea nil has traditionally been used to treat breathing irregularities. Male Swiss albino mice (20-25 +/- 2 g) were subjected to CS for 10 uninterrupted days in order to establish CS-induced ALI murine models. Dexamethasone (1 mg/kg), In.Mcx (100 200, and 300 mg/kg) and normal saline (10 mL/kg) were given to respective animal groups, 1 h before CS-exposure. 24 h after the last CS exposure, the lungs and bronchoalveolar lavage fluid (BALF) of all euthanized mice were harvested. Altered alveolar integrity and elevated lung weightcoefficient, total inflammatory cells, oxidative stress, expression of pro-inflammatory cytokines (IL-10 and IL-6) and chemokines (KC) were significantly decreased by In.Mcx in CS-exposed mice. In.Mcx also revealed significant lowering IL-10, IL-6 and KC expression in CSE (4 %)-activated RAW 264.7 macrophage. Additionally, In.Mcx showed marked enzyme inhibition activity against Acetylcholinesterase, Butyrylcholinesterase and Lipoxygenase. Importantly, In.Mcx dose-dependently and remarkably suppressed the CS-induced oxidative stress via not only reducing the MPO, TOS and MDA content but also improving TAC production in the lungs. Accordingly, HPLC analysis revealed the presence of many important antioxidant components. Finally, In.Mcx showed a marked decrease in the NF-KB expression both in in vivo and in vitro models. Our findings suggest that In.Mcx has positive therapeutic effects against CS-induced ALI via suppressing uncontrolled inflammatory response, oxidative stress, lipoxygenase and NF-KB p65 pathway

    Whole Genome Sequence of Dermacoccus abyssi MT1.1 Isolated from the Challenger Deep of the Mariana Trench Reveals Phenazine Biosynthesis Locus and Environmental Adaptation Factors

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    Dermacoccus abyssi strain MT1.1T is a piezotolerant actinobacterium that was isolated from Mariana Trench sediment collected at a depth of 10898 m. The organism was found to produce ten dermacozines (A‒J) that belonged to a new phenazine family and which displayed various biological activities such as radical scavenging and cytotoxicity. Here, we report on the isolation and identification of a new dermacozine compound, dermacozine M, the chemical structure of which was determined using 1D and 2D-NMR, and high resolution MS. A whole genome sequence of the strain contained six secondary metabolite-biosynthetic gene clusters (BGCs), including one responsible for the biosynthesis of a family of phenazine compounds. A pathway leading to the biosynthesis of dermacozines is proposed. Bioinformatic analyses of key stress-related genes provide an insight into how the organism adapted to the environmental conditions that prevail in the deep-sea

    Determination of Phenolic Compounds in Various Propolis Samples Collected from an African and an Asian Region and Their Impact on Antioxidant and Antibacterial Activities

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    The biological activities of propolis samples are the result of many bioactive compounds present in the propolis. The aim of the present study was to determine the various chemical compounds of some selected propolis samples collected from Palestine and Morocco by the High-Performance Liquid Chromatography–Photodiode Array Detection (HPLC-PDA) method, as well as the antioxidant and antibacterial activities of this bee product. The chemical analysis of propolis samples by HPLC-PDA shows the cinnamic acid content in the Palestinian sample is higher compared to that in Moroccan propolis. The results of antioxidant activity demonstrated an important free radical scavenging activity (2,2-Diphenyl-1-picrylhydrazyl (DPPH); 2,2â€Č-azino-bis 3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and reducing power assays) with EC50 values ranging between 0.02 ± 0.001 and 0.14 ± 0.01 mg/mL. Additionally, all tested propolis samples possessed a moderate antibacterial activity against bacterial strains. Notably, Minimum Inhibitory Concentrations (MICs) values ranged from 0.31 to 2.50 mg/mL for Gram-negative bacterial strains and from 0.09 to 0.125 mg/mL for Gram-positive bacterial strains. The S2 sample from Morocco and the S4 sample from Palestine had the highest content of polyphenol level. Thus, the strong antioxidant and antibacterial properties were apparently due to the high total phenolic and flavone/flavonol contents in the samples. As a conclusion, the activities of propolis samples collected from both countries are similar, while the cinnamic acid in the Palestinian samples was more than that of the Moroccan samples
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