The in vitro and in vivo investigation of biological activities and phenolic analysis of Helichrysum plicatum subsp. plicatum

In Turkey, Helichrysum genus is represented by 26 taxa belonging to 20 species in Turkish flora of which 14 ones are endemic to Turkey. The aerial parts of Helichrysum plicatum subsp. plicatum are used kidney stones, kidney and stomach ailments. The extraction procedures and solvents are important step in processing of bioactive constituents from the plant materials. Therefore, the aim of this study was to evaluate in vitro antioxidant, antimicrobial, anti-urease, anticholinesterase and in vivo antiinflammatory activities of Helichrysum plicatum subsp. plicatum different extracts. In addition, the phenolic characterization of the Soxhlet and maceration methanol extracts which showed significant antioxidant, anti-urease, antimicrobial, anti-inflammatory and anticholinesterase activities were performed by HPLC-DAD and LC-MS/MS. In the present study, the Soxhlet methanol extract exhibited strong antioxidant, antimicrobial and anticholinesterase activities than other extracts. The maceration methanol extract showed the strongest anti-urease activity. The Soxhlet methanol and maceration methanol extracts showed in vivo anti-inflammatory activities very close to each other. As a result of this study, chlorogenic acid, dicaffeoylquinic acid, luteolin, luteolin-7-O-glucoside, naringenin-O-hexoside and isoquercitrin compounds were analysed in plant. Therefore, it is thought that methanol extracts can be used as a natural source in the future for food and pharmaceutical industries

Investigation of antioxidant and anticonvulsant activity of Hypericum triquetrifolium Turra

Epilepsy is a state characterized by sudden, recurrent epileptic seizures that are not initiated by an identifiable event. There are various studies has been shown that Hypericum species may be used for their anticonvulsant potentials. Besides, the relationship between anticonvulsant activity and antioxidant effect has already been shown in the literature. In the current study, H. triquetrifolium was investigated for the first time for its potential antioxidant and anticonvulsant potential using in vitro and in vivo test models. H. triquetrifolium extracts were tested with DPPH assay, FRAP assay, copper (II) ion reducing antioxidant capacity assay, and acetylcholinesterase inhibitory activity assay to understand their antioxidant potential. Especially, methanolic extract of H. triquetrifolium was shown the highest antioxidant activity. Moreover, a pentylenetetrazole (PTZ, 80 mg/kg, i.p.)-induced seizure model was conducted to analyze the anticonvulsant activities of H. triquetrifolium extracts in mice. In addition, this study revealed that H. triquetrifolium decreased the ratio of severe seizures and increased the mean onsite of mortality and survival rate in a dose-dependent manner. It is thought that the anticonvulsant effect may be either related to the antioxidant potential of H. triquetrifolium or its interference in the GABAergic system

Experimental and theoretical investigation of the fluid behavior during polymeric fiber formation with and without pressure

The fabrication of polymeric micro/nanofibers is gaining attention due to their use in an array of applications including tissue engineering scaffolds, nanosensors, and fiber-reinforced composites. Despite their versatile nature, polymeric fibers are widely underutilized due to the lack of reliable, large-scale production techniques. Upon the discovery of centrifugal spinning and, recently, pressurized gyration techniques, new research directions have emerged. Here, we report a comprehensive study detailing the optimal conditions to significantly improve the morphology, homogeneity, and yield of fibers of varying diameters. A series of polymeric fibers was created using a 21 wt.% solution of polyethylene oxide in distilled water and the fluid behavior was monitored inside a transparent reservoir using a high-speed camera. Fabrication of the fibers took less than 1 s. Using centrifugal spinning, we studied the formation of the fibers at three different rotational speeds, and for pressurized gyration, one rotational speed was studied with three different nitrogen gas pressures. Using the pressurized gyration technique at a gas pressure of 0.3 MPa, there was significant improvement in the production yield of the fibers. We found a strong correlation between the variation of pressure and the rate of the solution leaving the reservoir with the improved morphology of the fibers. The use of reduced power techniques, like centrifugal spinning and pressured gyration, to yield high-quality nonwoven nanofibers and microfibers in large quantities is important due to their use in rapidly expanding markets. (C) 2019 Author(s)

Synthesis and investigation of anti-inflammatory and anticonvulsant activities of novel coumarin-diacylated hydrazide derivatives

A number of novel coumarin derivatives synthesized by the reaction of 3-carbonyl chloride coumarin with some substituted aryl acid hydrazides to investigate their anti-inflammatory and anticonvulsant activities. Carrageenan (0.1 ml of 1%, w/v) was injected subplantarly in the right paw of rats to induce an acute model of inflammation. Anti-inflammatory efficacy was evaluated for 5 hours at 3 different dosages 5, 10, 25 mg/kg. After that, the changes in the level of paw edema volumes and percentage inhibition of all groups were observed and the most effective coumarin derivative was found as N'-(2-hyroxybenzoyl)-2-oxo-2H-chromene-3-carbohydrazide. In addition, N'-(2-oxo-2H-chromene-3-carbonyl)nicotinohydrazide, (E)-N'-(3-(4-hydroxyphenyl)acryloyl)-2-oxo-2H-chromene-3-carbohydrazide, and N'-(5-amino-2-hydroxybenzoyl)-2-oxo-2H-chromone-3carbohydrazide showed their anti-inflammatory effects in a dose-dependent manner. On the other hand, pentylenetetrazole (PTZ, 80 mg/kg, i.p.)-induced seizure model was used to investigate the anticonvulsant activities of six newly synthesized coumarin derivatives in mice. Hybrid compound of salicylic acid hydrazide and 3-carbonyl chloride coumarin (8d) was found the most promising anticonvulsant agent among all treatment groups according to the onset of seizure and survival rate. Moreover, (E)-N'-cinnamoyl-2-oxo-2H-chromene-3-carbohyrazide (8b) and (E)-N'-(3-(4-hyroxy phenyl)acryloyl)-2-oxo-2H-chromene-3-carbohydrazide (8c) has potential anticonvulsant efficiency in low doses (30 mg/kg). The anticonvulsant effect of these coumarin derivatives may be through enhanced GABA-mediated inhibition in the brain. (C) 2020 Published by Elsevier B.V. on behalf of King Saud University

Bazı geleneksel tıbbi bitkilerin antidiyabetik etkinliğinin ve etki mekanizmasının aydınlatılması

Amaç: Diabetes mellitus hiperglisemi ile karakterize metabolik bir hastalıktır. Çok sayıda tıbbi bitkiden izole edilen bileşiklerin Tip 2 Diabetes Mellitus (T2DM) tedavisinde potansiyele sahip olduğu gösterilmiştir. Bu çalışmanın amacı, Thymus praecox subsp. skorpilii var. skorpilii ve Salvia triloba bitki ekstrelerinin (TPSE ve STE) olası antidiyabetik etkileri sayesinde T2DM'nin tıbbi tedavisini desteklemek, mevcut tedavide kullanılan oral antidiyabetik dozunun azaltılmasını sağlamak ve bu ilaçların olası yan etkilerini önlemektir. Gereç ve Yöntem: Dişi sıçanlarda T2DM, ilk olarak tek doz NA (100 mg/kg, i.p.) enjeksiyonu, 15 dakika sonrasında ise tek doz STZ (55 mg/kg, i.p.) enjeksiyonu yapılarak indüklendi. Kan glukoz değeri 200-400 mg/dl arasındaki sıçanlar T2DM kabul edildi. Yapılan OGTT, ITT, kan glukozu ölçümleriyle antidiyabetik etkinlikleri incelendi. Detaylı etki mekanizmasını aydınlatmak için diyabet gelişimi ile ilgili olduğu düşünülen enzimlerin miktarına ELISA testi yardımıyla bakıldı. Bulgular: Kan glukoz düzeylerini ciddi şekilde düşüren TPSE ve STE'nin OGTT ve ITT sonucunda güçlü antidiyabetik etkinlikleri olduğu gösterildi. Yapılan ELISA testleri sonucunda STE'nin serumda insülini artırdığı, TNF-α, IL-1β ve IL-6 miktarını önemli ölçüde düşürdüğü; dokularda ise AMPK, GLP-1 miktarını yükselttiği ve PEPCK, GLUT-2 miktarını azalttığı gösterildi. TPSE'nin ise serumda insülini artırdığı, TNF-α, IL-1β, IL-6, ALT ve kreatinin miktarlarını düşürdüğü; dokularda ise AMPK, GLP-1, PPARγ miktarını artırdığı, PEPCK, GLUT-2, α-glukosidaz, SGLT-1 ve SGLT-2 miktarlarını azalttığı gösterildi. Sonuçlar: TPSE, metformin ile kıyaslandığında güçlü bir antidiyabetik etki gösterdi ve STE'nin etkisi de TPSE yakındı. BSTRACT Aim: Diabetes mellitus is a metabolic disorder characterized by hyperglycemia. It has been shown that many compounds isolated from diverse medical plants have potential in the treatment of Type 2 Diabetes Mellitus (T2DM). The aims of this study are to support the medical therapy of T2DM owing to the possible antidiabetic effects of Thymus praecox subsp. skorpilii var. skorpilii and Salvia triloba extracts (TPSE and STE), to procure the antidiabetic dosage reducement in current therapies and to prevent side effects of those as well. Material and Methods: T2DM was induced with a single dosage STZ (55 mg/kg, i.p.) following 15 minutes after a single dosage NA (100 mg/kg, i.p.) in female rats. Rats whose blood glucose levels are between 200 and 400 mg/dl were accepted as T2DM. OGTT, ITT and blood glucose measurements were used. To enlighten the mechanisms of action in details, many enzymes, which are considered as involving in the development of T2DM were investigated via ELISA test. Results: TPSE and STE decreased blood glucose levels and exhibited an antidiabetic activity according to the results of OGTT and ITT. ELISA showed that in serum; STE increased the level of insulin while decreased the levels of TNF-α, IL-1β and IL-6 prominently. When it comes to tissues; STE increased the levels of AMPK and GLP-1 whereas decreased those of PEPCK, GLUT-2. TPSE in serum; provided an elevation in insulin and a drop in the levels of ALT, creatinine, TNF-α, IL-1β, IL-6. In addition TPSE in tissues increased amounts of AMPK, GLP-1, PPAR-γ while it decreased PEPCK, GLUT-2, α-glucosidase, SGLT-1, SGLT-2 levels. Conclusion: TPSE achieved a strong antidiabetic effect comparing with metformin and the efficacies of STE and TPSE were close

A novel reusable anti-COVID-19 transparent face respirator with optimized airflow

This novel face mask is designed to be a reusable respirator with a small and highly efficient disposable fabric filter. Respirator material requirements are reduced by 75% compared to traditional designs and allow repeated cleaning or sterilization. The probability of virus particle inhalation is reduced using novel air filtration pathways, through square-waveform design to increase filter airflow. Air enters the mask from right and left side filters, while the area in front of the mouth is isolated. Clear epoxy is used for a transparent frame, allowing lip-reading, and mask edges contain a silicone seal preventing bypass of the filters. The mask is manufactured using silicone molds, eliminating electricity requirements making it economical and viable in developing countries. Computational fluid dynamics numerical studies and Fluent ANSYS software were used to simulate airflow through the filter to optimize filter air path geometry and validate mask design with realistic human requirements. The breathing cycle was represented as a transient function, and N95 filter specifications were selected as a porous medium. The novel design achieved 1.2 x 10(-3)kg s(-1), 20% higher than human requirements, with air streamlines velocity indicating local high speed, forcing and trapping virus particles against filter walls through centrifugal forces

Optimization of Process-Control Parameters for the Diameter of Electrospun Hydrophilic Polymeric Composite Nanofibers

A composite nanofiber composed of three polymers, namely polyvinyl alcohol/polyvinyl pyrrolidone/polyethylene oxide, is produced. The experiments are constructed using three design of experiment techniques, Taguchi L-9, Taguchi L-27, and Screening method. The experiments are verified using the analysis of variance (ANOVA) method and later a mathematical model is developed using the regression method. The impact of electrospun processing parameters, namely applied voltage, flow rate, and working distance, on nanofibers' diameter is measured. The working distance is a significant factor in controlling the size of the fiber diameter, while the applied voltage has the lowest effect on it. As a result of the regression equation, a Genetic algorithm is used to find the optimum variables for the required fiber diameter, which is 156 nm for flow rate = 0.001 mL h(-1), voltage = 30 kV, and distance = 200 mm with a 3% difference from the experimental fiber diameter

Core-sheath polymer nanofiber formation by the simultaneous application of rotation and pressure in a novel purpose-designed vessel

Forming polymeric core-sheath nanofibers is gaining prominence owing to their numerous potential applications, most notably in functional scenarios such as antiviral filtration, which is attracting significant attention due to the current COVID pandemic. This study has successfully designed and constructed a novel pressurized gyration vessel to fabricate core-sheath polymer nanofibers. Several water-soluble and water-insoluble polymer combinations are investigated. Both polyethylene oxide and polyvinyl alcohol were used as the core while both poly(lactic acid) (PLA) and poly(caprolactone) (PCL) were used as the sheath; PLA and PCL were used as core and sheath, in different instances; respectively. The fluid behavior of the core-sheath within the vessel was studied with and without applied pressure using computational fluid dynamics to simulate the core-sheath flow within the chamber. A high-speed camera was used to observe the behavior of jetted solutions at core-sheath openings, and the best scenario was achieved using 6000 rpm spinning speed with 0.2 MPa (twice atmospheric) applied pressure. The surface morphology of core-sheath fibers was studied using a scanning electron microscope, and focused ion beam milling assisted scanning electron microscopy was used to investigate the cross-sectional features of the produced fibers. Laser confocal scanning microscopy was also used to verify the core-sheath structure of the fibers, which were further characterized by Fourier transform infrared spectroscopy and differential scanning calorimetry. Thus, using a variety of polymer combinations, we show, both theoretically and experimentally, how core-sheath fibers evolve in a vessel that can serve as a scalable manufacturing pressurized gyration production process

Metformin-Loaded Polymer-Based Microbubbles/Nanoparticles Generated for the Treatment of Type 2 Diabetes Mellitus

Type 2 diabetes mellitus (T2DM) is a chronic metabolic disease that is increasingly common all over the world with a high risk of progressive hyperglycemia and high microvascular and macrovascular complications. The currently used drugs in the treatment of T2DM have insufficient glucose control and can carry detrimental side effects. Several drug delivery systems have been investigated to decrease the side effects and frequency of dosage, and also to increase the effect of oral antidiabetic drugs. In recent years, the use of microbubbles in biomedical applications has greatly increased, and research into microactive carrier bubbles continues to generate more and more clinical interest. In this study, various monodisperse polymer nanoparticles at different concentrations were produced by bursting microbubbles generated using a T-junction microfluidic device. Morphological analysis by scanning electron microscopy, molecular interactions between the components by FTIR, drug release by UV spectroscopy, and physical analysis such as surface tension and viscosity measurement were carried out for the particles generated and solutions used. The microbubbles and nanoparticles had a smooth outer surface. When the microbubbles/nanoparticles were compared, it was observed that they were optimized with 0.3 wt % poly(vinyl alcohol) (PVA) solution, 40 kPa pressure, and a 110 μL/min flow rate, thus the diameters of the bubbles and particles were 100 ± 10 μm and 70 ± 5 nm, respectively. Metformin was successfully loaded into the nanoparticles in these optimized concentrations and characteristics, and no drug crystals and clusters were seen on the surface. Metformin was released in a controlled manner at pH 1.2 for 60 min and at pH 7.4 for 240 min. The process and structures generated offer great potential for the treatment of T2DM.