Centrifugal isolation of SARS-CoV-2: numerical simulation for purification of hospitals’ air

Biomechanics and Modeling in Mechanobiology - Coronavirus and its spread all over the world have been the most challenging crisis in 2020. Hospitals are categorized among the most vulnerable...     

Therapeutic potency of Wnt signaling antagonists in the pathogenesis of prostate cancer,current status and perspectives

Prostate cancer is a major cause of cancer-related death in males. Wnt/β-catenin signaling plays a critical role in the pathogenesis of this disease by regulating angiogenesis, drug resistance, cell proliferation, and apoptosis. Suppression of Wnt canonical or noncanonical signaling pathways via Wnt biological or pharmacological antagonists is a potentially novel therapeutic approach for patients with prostate cancer. This review summarizes the role of Wnt signaling inhibitors in the pathogenesis of prostate cancer for a better understanding and hence a better management of this disease.     

Molecular Design,Expression and Evaluation of PASylated Human Recombinant Erythropoietin with Enhanced Functional Properties

Erythropoietin (EPO) is the principal hormone which, has somewhat short half-life involved in the differentiation and regulation of circulating red blood cells. The present study was carried out to evaluate the capability of a polyethylene glycol mimetic technology as a biological alternative to improve pharmaceutical properties of human recombinant EPO. In silico models of EPO fused to 200 amino acids of proline, alanine, and serine (PAS) were initially generated and assessed by molecular dynamic (MD) simulation. The fluctuations of the modeled structure reached a plateau after 6000 ps of MD simulation. The Phi and psi analysis showed >99.2% of residues were located in the allowed regions. An expression vector consisting of EPO cDNA tagged to PAS coding sequences was synthesized and expressed in CHO-K1 Cells. The produced PASylated molecule was purified and characterized by standard analytical methods. The molecular weight of fusion protein was expanded to 70 kDa using sodium dodecyl sulfate polyacrylamide gel electrophoresis method. Analytical size exclusion chromatography revealed an approximately sevenfold increase in apparent size of produced protein. Although the in vitro potency of the fusion protein was significantly reduced (1.26?±?0.05 vs. 0.24?±?0.03 ng/ml) but, the in vivo activity was considerably increased up to 1.58?×?10⁵ IU/ml in normocythemic mice assay. Pharmacokinetic animal studies revealed strongly 15.6-fold plasma half-life extension for the PASylated EPO (83.16?±?13.28 h) in comparison to epoetin α (8.5?±?2.4 h) and darbepoetin α (25.3?±?2.2h).     

Thyrsiferol Inhibits Mitochondrial Respiration and HIF-1 Activation

The cytotoxic marine red algal metabolite thyrsiferol (1) was found to inhibit hypoxia-induced hypoxia-inducible factor-1 (HIF-1) activation in T47D human breast tumor cells (66% inhibition at 3 μM). Compound 1 also suppressed hypoxic induction of HIF-1 target genes (VEGF, GLUT-1) at the mRNA level, and displayed tumor cell line-selective time-dependent inhibition of cell viability/proliferation. Mechanistic studies revealed that 1 selectively suppressed mitochondrial respiration at Complex I (IC(50) 3 μM). Thyrsiferol represents a prototypical, structurally unique electron transport chain inhibitor. The apparent rotenone-like activity may contribute to the observed cytotoxicity of 1 and play an important role in Laurencia chemical defense.     

Mapping binding domains of kininogens on endothelial cell cytokeratin 1

Human cytokeratin 1 (CK1) in human umbilical vein endothelial cells (HUVEC) is expressed on their membranes and is able to bind high molecular weight kininogen (HK) (Hasan, A. A. K., Zisman, T., and Schmaier, A. H. (1998) Proc. Natl. Acad. Sci. U. S. A. 95, 3615-3620). New investigations have been performed to demonstrate the HK binding domain on CK1. Four overlapping recombinant (r) CK1 proteins were produced in Escherichia coli by a glutathione S-transferase gene fusion system. Biotin-HK specifically bound to rCK128 and rCK131 in the presence of Zn2+ but not to Deleted1-6rCK131. Recombinant CK128 and rCK131 also inhibited biotin-HK binding to HUVEC with IC50 of 0.4 and 0.5 microM, respectively. Alternatively, rCK114 and Deleted1-6rCK131 did not inhibit binding at concentrations >/=1 microM. Seven sequential 20 amino acid peptides of CK1 were prepared to cover the protein coded by exons 1-3. Only the first peptide (GYG20) coded by exon 1 significantly inhibited HK binding to HUVEC with an IC50 of 35 microM. Fine mapping studies isolated two overlapping peptides also coded by exon 1 (GPV15 and PGG15) that inhibited binding to HUVEC with IC50 of 18 and 9 microM, respectively. A sequence scrambled peptide of PGG15 did not block binding to HUVEC and biotin-GPV20 specifically bound to HK. Peptides GPV15 and PGG15 also blocked prekallikrein activation on endothelial cells. However, inhibition of PK activation by peptide PGG15 occurred at 10-fold lower concentration (IC50 = 1 microM) than inhibition of biotin-HK binding to HUVEC (IC50 = 10 microM). These studies indicate that HK binds to a region of 20 amino acids coded by exon 1 on CK1 which is carboxyl-terminal to its glycine-rich amino-terminal globular domain. Furthermore, HK binding to CK1 modulates PK activation on HUVEC.     

Co‐utilization of acidified glycerol pretreated‐sugarcane bagasse for microbial oil production by a novel Rhodosporidium strain

Acidified glycerol pretreatment is very effective to deconstruct lignocellulosics for producing glucose. Co‐utilization of pretreated biomass and residual glycerol to bioproducts could reduce the costs associated with biomass wash and solvent recovery. In this study, a novel strain Rhodosporidium toruloides RP 15, isolated from sugarcane bagasse, was selected and tested for coconversion of pretreated biomass and residual glycerol to microbial oils. In the screening trails, Rh. toruloides RP 15 demonstrated the highest oil production capacity on glucose, xylose, and glycerol among the 10 strains. At the optimal C:N molar ratio of 140:1, this strain accumulated 56.7, 38.3, and 54.7% microbial oils based on dry cell biomass with 30 g/L glucose, xylose, and glycerol, respectively. Furthermore, sugarcane bagasse medium containing 32.6 g/L glucose from glycerol‐pretreated bagasse and 23.4 g/L glycerol from pretreatment hydrolysate were used to produce microbial oils by Rh. toruloides RP 15. Under the preliminary conditions without pH control, this strain produced 7.7 g/L oil with an oil content of 59.8%, which was comparable or better than those achieved with a synthetic medium. In addition, this strain also produced 3.5 mg/L carotenoid as a by‐product. It is expected that microbial oil production can be significantly improved through process optimization.     

A newly identified c.1824_1828dupATACG mutation in exon 13 of the GAA gene in infantile-onset glycogen storage disease type II (Pompe disease)

Pompe disease or glycogen storage disease type II is a glycogen storage disorder associated with malfunction of the acid α-glucosidase enzyme (GAA; EC.3.2.1.3) leading to intracellular aggregations of glycogenin muscles. The infantile-onset type is the most life-threatening form of this disease, in which most of patients suffer from cardiomyopathy and hypotonia in early infancy. In this study, a typical case of Pompe disease was reported in an Iranian patient using molecular analysis of the GAA gene. Our results revealed a new c.1824_1828dupATACG mutation in exon 13 of the GAA gene. In conclusion, with the finding of this novel mutation, the genotypic spectrum of Iranian patients with Pompe disease has been extended, facilitating the definition of disease-related mutations.