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Molecular mechanism(s) of regulation(s) of c-MET/HGF signaling in head and neck cancer
Get PDFHead and neck cancer is the sixth most common cancer across the globe. This is generally associated with tobacco and alcohol consumption. Cancer in the pharynx majorly arises through human papillomavirus (HPV) infection, thus classifying head and neck squamous cell carcinoma (HNSCC) into HPV-positive and HPV-negative HNSCCs. Aberrant, mesenchymal-epithelial transition factor (c-MET) signal transduction favors HNSCC progression by stimulating proliferation, motility, invasiveness, morphogenesis, and angiogenesis. c-MET upregulation can be found in the majority of head and neck squamous cell carcinomas. c-MET pathway acts on several downstream effectors including phospholipase C gamma (PLCγ), cellular Src kinase (c-Src), phosphotidylinsitol-3-OH kinase (PI3K), alpha serine/threonine-protein kinase (Akt), mitogen-activated protein kinase (MAPK), and wingless-related integration site (Wnt) pathways. c-MET also establishes a crosstalk pathway with epidermal growth factor receptor (EGFR) and contributes towards chemoresistance in HNSCC. In recent years, the signaling communications of c-MET/HGF in metabolic dysregulation, tumor-microenvironment and immune modulation in HNSCC have emerged. Several clinical trials have been established against c-MET/ hepatocyte growth factor (HGF) signaling network to bring up targeted and effective therapeutic strategies against HNSCC. In this review, we discuss the molecular mechanism(s) and current understanding of c-MET/HGF signaling and its effect on HNSCC.O
Quality Attributes of Chitosan-Coated Cornelian Cherry (Cornus mas L.) Fruits under Different Storage Temperatures
Get PDFTemperature is the dominant environmental stimulus that influences the postharvest quality, visual appearance, and nutritional content of fruits. Temperature hastens fruit ripening and senescence by the impact on respiration rate and the acceleration of metabolic reactions. This study was conducted to select the optimized temperature for preserving the quality-related traits and antioxidant potential of cornelian cherry fruits after harvest. The fruits were treated with 1% chitosan and then kept under 0, 5, 10, and 21oC for 21 days. The results revealed that fruits kept under lower than room temperature (21oC) better retained antioxidant capacity and had higher levels of phenolics, flavonoids, and anthocyanins and even higher antioxidant enzyme activity, hence attaining prolonged postharvest life. Considering the quantity attributes and the shelf life, the temperature of choice was 0oC. Zero temperature was also the best to keep the antioxidant capacity of cornelian cherry fruits. Overall, the results showed that low temperature and chitosan pretreatment provide an efficient method for maintaining the nutritional quality and antioxidant capacity of cornelian cherry fruits during storage time.O
Determining the phytotoxicity of rubber granulate from waste tires
No full textThe annually increasing global production of tires ranges around 1 billion and the number of waste tires is growing too. A question comes to the fore how to handle the waste to prevent environmental risks. The most advanced recycling facilities can process waste tires by sophisticated methods leading to their further use. One of products is a so-called rubber granulate which enjoys great interest of gardeners who use it instead organic mulch. In relation with this research, phytotoxicity of rubber granulate made from waste tires was studied in laboratory conditions using a test kit (PhytotoxkitTM) for the determination of inhibitory/stimulating effect. The testing was made on the reference soil and tested seeds were the seeds of white mustard (Sinapis alba L). The granulate was applied onto the soil at rates of 5%, 10%, 25%, 50% and 75%. Research results demonstrated the inhibition of Sinapis alba L. seeds already from the rate of 5%, i.e. 6.50%. In the other rates, the inhibition ranged between 26.37% and 62.36%. The granulate is therefore considered phytotoxic and should not be used on the soil.Published Versio
COVID-19 vaccine equity for the Global South: Vaccination challenges and opportunities for small and poor countries
Get PDFThe effects of COVID-19 have significantly interrupted countries and the social order across the globe. However, the developing countries which could not manufacture or even buy the most wanted commodity: COVID-19 Vaccine, looked on as the situation got worse even in the wealthy nations. Diplomacy seems a ray of hope among developing countries as wealthy nations have used almost all the vaccines themselves. The goal of this study was to critically analyze the challenges and opportunities around the COVID-19 pandemic, especially vaccine distribution and access, and the role of diplomacy in this process in selected countries in Africa. We used the narrative literature review approach. We examined the cases of Uganda, Ghana, and South Africa on the COVID-19 vaccine distribution. We found minimal accessibility and affordability of vaccines in developing nations. African and other developing countries have since depended on vaccine donations. Affordability makes it challenging for wealthy countries to lend a hand while ensuring their population and market needs are catered for. We propose that nationals in the Global South must strengthen their diplomatic systems and negotiation skills with wealthy countries while reinforcing public health systems. Developing countries must build alliances to engage with high-income countries as equal partners.O
Economic growth effects of de facto and de jure trade globalization in ECOWAS
Get PDFThis paper examines the dynamics of trade globalization by analysing and comparing the economic growth effect of overall trade globalization with the growth effects of de facto and de jure trade globalization in the economic community of west African states (ECOWAS). Using fixed effects and random effects models, we separate the de facto measure of trade globalization from the de jure measure to prove that de facto trade globalization significantly and positively contributes to economic growth in ECOWAS, whereas de jure trade globalization does not. We also use pooled mean group estimates to prove that the growth effect of de facto trade globalization is significant only in the short run. By implication, relying only on the results of overall trade globalization can be misleading for policymakers, considering that the de facto and de jure measures of trade globalization yield different growth results. The findings of this study can aid policymakers within the region in identifying proper measures and tailoring trade policies to gain reasonable competitive advantage among other economic communities.O
Toxicological effects of nanoselenium in animals
Get PDFThe productivity and sustainability of livestock production systems are heavily influenced by animal nutrition. To maintain homeostatic balance in the body of the animal at different phases of life, the percentage of organically active minerals in livestock feed must be optimized. Selenium (Se) is a crucial trace mineral that is required for the maintenance of many functions of the body. Se nanoparticles (SeNPs) attracted considerable interest from researchers for a variety of applications a decade ago, owing to their extraordinary properties. SeNPs offer significant advantages over larger-sized materials, by having a comparatively wider surface area, increased surface energy, and high volume. Despite its benefits, SeNP also has toxic effects, therefore safety concerns must be taken for a successful application. The toxicological effects of SeNPs in animals are characterized by weight loss, and increased mortality rate. A safe-by-strategy to certify animal, human and environmental safety will contribute to an early diagnosis of all risks associated with SeNPs. This review is aimed at describing the beneficial uses and potential toxicity of SeNPs in various animals. It will also serve as a summary of different levels of SeNPs which should be added in the feed of animals for better performance.O
Analysis of Field View from Tractor and Trailer Units Using the Method of Terrestrial Laser Scanning
Get PDFHaving a proper view from the cabin of agricultural and forest machines is one of the main factors affecting work safety and efficiency. In forestry, machine operators very often perform working activities also in the rear of the cabin. Requirements, criteria and test procedures for the field of view from the tractor cabin are stipulated by the international technical standard ISO 5721. This study evaluates field view parameters from the cabin of the tractor (Valtra T 6300) and trailer (STS 12T) unit. In accordance with the test procedures, prescribed parameters were evaluated for the forward field of view; values for the rear field of view were determined in addition to outside the standard. In order to achieve more accurate measurements and faster evaluation of data, one of the latest methods-using laser pulse reflections (method of terrestrial laser scanning)-was employed. The results of our study demonstrate that even the construction of machines manufactured before the above-mentioned standard came to force can meet the current requirements, except for minor deviations.O
Effect of Biosynthesized Silver Nanoparticles on Bacterial Biofilm Changes in S. aureus and E. coli
Get PDFOne approach for solving the problem of antibiotic resistance and bacterial persistence in biofilms is treatment with metals, including silver in the form of silver nanoparticles (AgNPs). Green synthesis is an environmentally friendly method to synthesize nanoparticles with a broad spectrum of unique properties that depend on the plant extracts used. AgNPs with antibacterial and antibiofilm effects were obtained using green synthesis from plant extracts of Lagerstroemia indica (Ag- NPs_LI), Alstonia scholaris (AgNPs_AS), and Aglaonema multifolium (AgNPs_AM). Nanoparticles were characterized by transmission electron microscopy (TEM) and energy-dispersive X-ray spectroscopy (EDX) analysis. The ability to quench free radicals and total phenolic content in solution were also evaluated. The antibacterial activity of AgNPs was studied by growth curves as well as using a diffusion test on agar medium plates to determine minimal inhibitory concentrations (MICs). The effect of AgNPs on bacterial biofilms was evaluated by crystal violet (CV) staining. Average minimum inhibitory concentrations of AgNPs_LI, AgNPs_AS, AgNPs_AM were 15+- 5, 20 +- 5, 20 + 5 g/mL and 20+- 5, 15 +- 5, 15 + 5 g/mL against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria, respectively. The E. coli strain formed biofilms in the presence of AgNPs, a less dense biofilm than the S. aureus strain. The highest inhibitory and destructive effect on biofilms was exhibited by AgNPs prepared using an extract from L. indica.O
Potential effect of wetting agents added to agricultural sprays on the stability of soil aggregates
Get PDFA potential effect of adjuvants/wetting agents added to the spray mixture on the water stability of soil aggregates (WSA) in agricultural soil was studied. Nine sites were chosen in the Czech Republic. Each site was mapped using representative soil pits (depth min. 1.3 m). A total of 54 mixed samples were collected from topsoil horizons on the selected sites. The samples were exposed to the action of four different types of wetting agents (organosilicone wetting agent; methyl ester of rapeseed oil; mixture of methyl ester palmitic and oleic acids; isodecyl alcohol ethoxylate), which are the most common wetting agents used in agriculture in the Czech Republic. WSA was determined before and after the addition of wetting agents (WA). Initial WSA values were at the same level in a majority of sampling points. Two sites were an exception, on which Haplic Luvisols and Relictistagnic Fluvisols occurred. These soil types featured the lowest WSA values. After the addition of WA across the sampling points, average WSA values exhibited a demonstrable trend: WSA of control sample (without the WA application) was at all times higher than in samples with the addition of WA. If the measured WSA values are compared in terms of overall means, it is evident that the control variant always exhibited the highest WSA value (on average 44.04 %) and the variants with the application of WA showed always WSA values lower by min 16 %. The worst effect on WSA was that of wetting agents whose basic component was methyl ester of rapeseed. These wetting agents caused a decrease in WSA by more than 50 %. All soil samples were also analysed for basic soil parameters (glomalin, oxidizable carbon - C-ox, pH, Na, P, Ca, K, Mg) in order to determine their potential influence on aggregate stability and to possibly eliminate the negative impact of WA. In this respect, only a significant influence of C-ox content on WSA was recorded, which positively correlated with the stability of soil aggregates.O
Response of Winter Wheat (Triticum aestivum L.) to Fertilizers with Nitrogen-Transformation Inhibitors and Timing of Their Application under Field Conditions
Get PDFWinter wheat is a widely cultivated crop that requires high inputs of nitrogen (N) fertilization, which is often connected with N losses. The application of fertilizers with nitrification (NI) and urease inhibitors (UI) is an opportunity to eliminate the risk of N losses and improve N availability to plants. The aim of this study is to compare the effect of conventional nitrogen fertilizers with fertilizers containing nitrogen-transformation inhibitors as well as to evaluate the timing of their application on the wheat-grain yield and quality under the conditions of a three-year field experiment. The examined fertilizers with inhibitors were applied in a single dose or in a split application in combination with conventional fertilizers. The single application of urea with NI and/or UI resulted in a relatively average increase in the grain yield, while protein content and the Zeleny-test values were significantly increased compared to the split N application. The more significant effect of urea with NI and UI was found under the moisture-rich conditions compared to the drier conditions. A significant increase in the grain yield (by 6.3%) and in the Zeleny-test value (by 16.5%) was observed after inhibited urea application comparing to the control treatment (without inhibitors).O