Blockchain for IoV in 6G environment: review solutions and challenges

Cluster Computing - In this era of modern digital technologies, the Internet of Vehicles (IoVs) is omnipresent and can be used for varied purposes. However, these devices have scalability,...     

From biotechnology principles to functional and low-cost metallic bionanocatalysts

Chemical, physical and mechanical methods of nanomaterial preparation are still regarded as mainstream methods, and the scientific community continues to search for new ways of nanomaterial preparation. The major objective of this review is to highlight the advantages of using green chemistry and bionanotechnology in the preparation of functional low-cost catalysts. Bionanotechnology employs biological principles and processes connected with bio-phase participation in both design and development of nano-structures and nano-materials, and the biosynthesis of metallic nanoparticles is becoming even more popular due to; (i) economic and ecologic effectiveness, (ii) simple one-step nanoparticle formation, stabilisation and biomass support and (iii) the possibility of bio-waste valorisation. Although it is quite difficult to determine the precise mechanisms in particular biosynthesis and research is performed with some risk in all trial and error experiments, there is also the incentive of understanding the exact mechanisms involved. This enables further optimisation of bionanoparticle preparation and increases their application potential. Moreover, it is very important in bionanotechnological procedures to ensure repeatability of the methods related to the recognised reaction mechanisms. This review, therefore, summarises the current state of nanoparticle biosynthesis. It then demonstrates the application of biosynthesised metallic nanoparticles in heterogeneous catalysis by identifying the many examples where bionanocatalysts have been successfully applied in model reactions. These describe the degradation of organic dyes, the reduction of aromatic nitro compounds, dehalogenation of chlorinated aromatic compounds, reduction of Cr(VI) and the synthesis of important commercial chemicals. To ensure sustainability, it is important to focus on nanomaterials that are capable of maintaining the important green chemistry principles directly from design inception to ultimate application.     

Pulsed feeding during fed-batch fungal fermentation leads to reduced viscosity without detrimentally affecting protein expression

The goal in this study was to determine if pulsed addition of substrate could be used to alter filamentous fungal morphology during fermentation, to result in reduced broth viscosity. In all experiments, an industrially relevant strain of Aspergillus oryzae was grown in 20-liter fermentors. As a control, cultures were fed limiting substrate (glucose) continuously. Tests were performed by altering the feeding strategy so that the same total amount of glucose was fed in repeated 300-s cycles, with the feed pump on for either 30 or 150 s during each cycle. Variables indicative of cellular metabolic activity (biomass concentration, oxygen uptake rate, base consumed for pH control) showed no significant difference between continuous and pulse-fed fermentations. In addition, there was no significant difference between total extracellular protein expression or the apparent distribution of these proteins. In contrast, fungal mycelia during the second half of pulse-fed fermentations were approximately half the size (average projected area) of fungi during fermentations with continuous addition of glucose. As a result, broth viscosity during the second half of pulse-fed fermentations was approximately half that during the second half of continuous fermentations. If these results prove to be applicable for other fungal strains and processes, then this method will represent a simple and inexpensive means to reduce viscosity during filamentous fungal fermentation.     

Ubiquitin chains earmark GPCRs for BBSome-mediated removal from cilia

Regulated trafficking of G protein–coupled receptors (GPCRs) controls cilium-based signaling pathways. β-Arrestin, a molecular sensor of activated GPCRs, and the BBSome, a complex of Bardet–Biedl syndrome (BBS) proteins, are required for the signal-dependent exit of ciliary GPCRs, but the functional interplay between β-arrestin and the BBSome remains elusive. Here we find that, upon activation, ciliary GPCRs become tagged with ubiquitin chains comprising K63 linkages (UbK63) in a β-arrestin–dependent manner before BBSome-mediated exit. Removal of ubiquitin acceptor residues from the somatostatin receptor 3 (SSTR3) and from the orphan GPCR GPR161 demonstrates that ubiquitination of ciliary GPCRs is required for their regulated exit from cilia. Furthermore, targeting a UbK63-specific deubiquitinase to cilia blocks the exit of GPR161, SSTR3, and Smoothened (SMO) from cilia. Finally, ubiquitinated proteins accumulate in cilia of mammalian photoreceptors and Chlamydomonas cells when BBSome function is compromised. We conclude that Ub chains mark GPCRs and other unwanted ciliary proteins for recognition by the ciliary exit machinery.     

Effect of Concomitant Administration of L-Glutamine and Cycloart-23-ene-3β, 25-diol (B2) with Sitagliptin in GLP-1 (7–36) Amide Secretion,Biochemical and Oxidative Stress in Streptozotocin - Nicotinamide Induced Diabetic Sprague Dawley Rats

Previously we have reported that, cycloart-23-ene-3β, 25-diol (called as B2) and L-glutamine stimulated glucagon like peptide-1 (GLP-1) (7–36) amide secretion diabetic rats. The objective of present investigation was to investigate the concomitant administration of cycloart-23-ene-3β, 25-diol+sitagliptin and L-glutamine+sitagliptin in streptozotocin - nicotinamide induced diabetic Sprague Dawley. Type 2 diabetes was induced in overnight fasted male Sprague Dawley rats pre-treated with nicotinamide (100 mg/kg, i.p.) followed by administration of streptozotocin (55 mg/kg, i.p.) 20 min after. The rats were divided into; I- non-diabetic, II- diabetic control, III- Sitagliptin (5 mg/kg, p.o.)+cycloart-23-ene-3β, 25-diol (1 mg/kg, p.o.), IV- Sitagliptin (5 mg/kg, p.o.)+L-glutamine (1000 mg/kg, p.o.). The concomitant treatment of cycloart-23-ene-3β, 25-diol and L-glutamine with sitagliptin was 8 weeks. Plasma glucose, body weight, food and water intake were determined every week. Glycosylated haemoglobin, lipid profile, plasma and colonic active (GLP-1) (7–36) amide, plasma and pancreatic insulin, histology of pancreata and biomarkers of oxidative stress were measured after 8^th week treatment. Concomitant administration of cycloart-23-ene-3β, 25-diol and L-glutamine with sitagliptin significantly (p<0.001) reduced plasma glucose, glyoxylated haemoglobin, lipid profile and oxidative stress parameters compared to diabetic control groups. Both concomitant treatment increased plasma and pancreatic insulin as well as plasma and colonic active (GLP-1) (7–36) amide secretion. Histological analysis by Gomori staining observed less destruction of pancreatic β cells. The result obtained from this study; it is concluded that concomitant administration of cycloart-23-ene-3β, 25-diol+sitagliptin and L-glutamine+sitagliptin showed additive antihyperglycaemic effect in diabetic rats.     

Antidiabetic properties of aqueous and methanol extracts from the trunk bark of Ceiba pentandra in type 2 diabetic rat

The type 2 diabetes is one of the major global health issues that affects millions of people. This study evaluated the antidiabetic activity of aqueous extracts (AECP) and methanol extracts (MECP) from Ceiba pentandra trunk bark on an experimental model of type 2 diabetes (T2D). This model was induced in rats by the combination of a high-fat diet (HFD) and a single dose of streptozotocin (40 mg/kg, intraperitoneal) at the seventh day of experimentation. Diabetes was confirmed on day 10 by fasting blood glucose more than or equal to 200 mg/dL. Diabetic animals still under HFD were treated orally and twice daily, with MECP and AECP (75 and 150 mg/kg) or metformin (40 mg/kg) for 14 days. During the experiment, blood glucose and animal weights were determined. Oral glucose tolerance test was performed on day 15, followed by animals sacrifice for blood, liver, and pancreas collection. Total cholesterol and triglyceride levels were evaluated in plasma, whereas malondialdehyde (MDA), glutathione (GSH), superoxide dismutase, and catalase were quantified in tissue homogenates. AECP and MECP significantly reduced the hyperglycemia by up to 62% and significantly improved the oral glucose tolerance test. The impaired levels of cholesterol and triglycerides registered in diabetic control were significantly reversed by both extracts at all the doses used. Alterations in diabetic pancreas weight, GSH, and MDA were also significantly reversed by plant extracts. AECP and MECP possess type 2 antidiabetic effects that could result from their ability to improve the peripheral use of glucose, lipid metabolism or from their capacity to reduce oxidative stress. These finding provide a new avenue for better control and management of early or advanced T2D.