Do innate killing mechanisms activated by inflammasomes have a role in treating melanoma?

Melanoma, as for many other cancers, undergoes a selection process during progression that limits many innate and adaptive tumor control mechanisms. Immunotherapy with immune checkpoint blockade overcomes one of the escape mechanisms but if the tumor is not eliminated other escape mechanisms evolve that require new approaches for tumor control. Some of the innate mechanisms that have evolved against infections with microorganisms and viruses are proving to be active against cancer cells but require better understanding of how they are activated and what inhibitory mechanisms may need to be targeted. This is particularly so for inflammasomes which have evolved against many different organisms and which recruit a number of cytotoxic mechanisms that remain poorly understood. Equally important is understanding of where these mechanisms will fit into existing treatment strategies and whether existing strategies already involve the innate killing mechanisms.     

Assessment of IL-10, IL-1ß and TNF-α gene polymorphisms in patients with peri-implantitis and healthy controls

Molecular Biology Reports - Peri-implantitis (PI) is a multifactorial condition caused by the interactions of pathogens and the host immune response. Previous studies have demonstrated a...     

Rapid upregulation of endothelial P-selectin expression via reactive oxygen species generation

Endothelial cell ICAM-1 upregulation in response to TNF-alpha is mediated in part by reactive oxygen species (ROS) generated by the endothelial membrane-associated NADPH oxidase and occurs maximally after 4 h as the synthesis of new protein is required. However, thrombin-stimulated P-selectin upregulation is bimodal, the first peak occurring within minutes. We hypothesize that this early peak, which results from the release of preformed P-selectin from within Weibel-Palade bodies, is mediated in part by ROS generated from the endothelial membrane-associated xanthine oxidase. We found that this rapid expression of P-selectin on the surface of endothelial cells was accompanied by qualitatively parallel increases in ROS generation. Both P-selectin expression and ROS generation were inhibited, dose dependently, by the exogenous administration of disparate cell-permeable antioxidants and also by the inhibition of either of the known membrane-associated ROS-generating enzymes NADPH oxidase or xanthine oxidase. This rapid, posttranslational cell signaling response, mediated by ROS generated not only by the classical NADPH oxidase but also by xanthine oxidase, may well represent an important physiological trigger of the microvascular inflammatory response.     

Transmission of RNA silencing signal through grafting confers virus resistance from transgenically silenced tobacco rootstocks to non-transgenic tomato and tobacco scions

We examined the transmission of RNA silencing signal in non-transgenic tomato and tobacco scions grafted onto the tobacco Sd1 rootstocks, which is silenced in both NtTOM1 and NtTOM3 required for tobamovirus multiplication. When the non-transgenic tomato scions were grafted onto the Sd1 rootstocks, RT-PCR analysis of the scions showed the reduced level of mRNA compared with that before grafting in both LeTH3 and LeTH1, tomato homologs of NtTOM1 and NtTOM3, respectively. siRNAs from both genes were detected in the scions after grafting but not before grafting. Further tomato scions were inoculated with Tomato mosaic virus (ToMV) and used for virus infection. They showed very low level of virus accumulation. Necrotic responding tobacco to tobamovirus was grafted onto the rootstock of Sdl. RT-PCR analysis showed low level expression of both NtTOM1 and NtTOM3 in the scions but siRNA was detected after grafting. When the leaves of scions were inoculated with ToMV or Tobacco mosaic virus, they produced very few local necrotic lesions (LNLs) while the control scions did many LNLs. These results suggest that RNA silencing was transmitted to non-transgenic tomato and tobacco scions after grafting onto the Sd1 rootstocks and that virus resistance was induced in the scions.     

Constructions of expression vectors of polyhydroxybutyrate-co-hydroxyvalerate (PHBV) and transient expression of transgenes in immature oil palm embryos

Polyhydroxybutyrate-co-hydroxyvalerate (PHBV) is a polyhydroxyalkanoate (PHA) bioplastic group with thermoplastic properties is thus high in quality and can be degradable. PHBV can be produced by bacteria, but the process is not economically competitive with polymers produced from petrochemicals. To overcome this problem, research on transgenic plants has been carried out as one of the solutions to produce PHBV in economically sound alternative manner. Four different genes encoded with the enzymes necessary to catalyze PHBV are bktB, phaB, phaC and tdcB. All the genes came with modified CaMV 35S promoters (except for the tdcB gene, which was promoted by the native CaMV 35S promoter), nos terminator sequences and plastid sequences in order to target the genes into the plastids. Subcloning resulted in the generation of two different orientations of the tdcB, pLMIN (left) and pRMIN (right), both 17.557 and 19.967 kb in sizes. Both plasmids were transformed in immature embryos (IE) of oil palm via Agrobacterium tumefaciens. Assays of GUS were performed on one-week-old calli and 90% of the calli turned completely blue. This preliminary test showed positive results of integration. Six-months-old calli were harvested and RNA of the calli were isolated. RT-PCR was used to confirm the transient expression of PHBV transgenes in the calli. The bands were 258, 260, 315 and 200 bp in size for bktB, phaB, phaC and tdcB transgenes respectively. The data obtained showed that the bktB, phaB, phaC and tdcB genes were successfully integrated and expressed in the oil palm genome.     

Biodegradation of feather waste by keratinase produced from newly isolated Bacillus licheniformis ALW1

Keratinase are proteolytic enzymes which have gained much attention to convert keratinous wastes that cause huge environmental pollution problems. Ten microbial isolates were screened for their keratinase production. The most potent isolate produce 25.2?U/ml under static condition and was primarily identified by partial 16s rRNA gene sequence as Bacillus licheniformis ALW1. Optimization studies for the fermentation conditions increased the keratinase biosynthesis to 72.2?U/ml (2.9-fold). The crude extracellular keratinase was optimally active at pH 8.0 and temperature 65?°C with 0.7% soluble keratin as substrate. The produced B. licheniformis ALW1 keratinase exhibited a good stability over pH range from 7 to 9 and over a temperature range 50–60?°C for almost 90?min. The crude enzyme solution was able to degrade native feather up to 63% in redox free system.     

Computational and Pharmacological Studies on the Antioxidant,Thrombolytic, Anti-Inflammatory,and Analgesic Activity of Molineria capitulata

Molineria capitulata is an ornamental plant that has traditionally been used to treat several chronic diseases. The present study was designed to examine the antioxidant, cytotoxic, thrombolytic, anti-inflammatory, and analgesic activities of a methanolic extract of M. capitulata leaves (MEMC) using both experimental and computational models. Previously established protocols were used to perform qualitative and quantitative phytochemical screening in MEMC. A computational study, including molecular docking and ADME/T analyses, was performed. The quantitative phytochemical analysis revealed the total phenolic and flavonoid contents as 148.67 and 24 mg/g, respectively. Antioxidant activity was assessed by examining the reducing power of MEMC, resulting in absorbance of 1.87 at 400 µg/mL, demonstrating a strong reduction capacity. The extract exhibited significant protection against blood clotting and showed the highest protein denaturation inhibition at 500 µg/mL. In both the acetic acid-induced writhing and formalin-induced paw-licking models, MEMC resulted in significant potential pain inhibition in mice. In the computational analysis, 4-hydroxybenzaldehyde, orcinol glucoside, curcapital, crassifogenin C, and 2,6-dimethoxy-benzoic acid displayed a strong predictive binding affinity against the respective receptors. These findings indicated that M. capitulata possesses significant pharmacological activities to an extent supported by computational studies.     

Genetic diversity of Salmonella Paratyphi A isolated from enteric fever patients in Bangladesh from 2008 to 2018

BackgroundThe proportion of enteric fever cases caused by Salmonella Paratyphi A is increasing and may increase further as we begin to introduce typhoid conjugate vaccines (TCVs). While numerous epidemiological and genomic studies have been conducted for S. Typhi, there are limited data describing the genomic epidemiology of S. Paratyphi A in especially in endemic settings, such as Bangladesh.Principal findingsWe conducted whole genome sequencing (WGS) of 67 S. Paratyphi A isolated between 2008 and 2018 from eight enteric disease surveillance sites across Bangladesh. We performed a detailed phylogenetic analysis of these sequence data incorporating sequences from 242 previously sequenced S. Paratyphi A isolates from a global collection and provided evidence of lineage migration from neighboring countries in South Asia. The data revealed that the majority of the Bangladeshi S. Paratyphi A isolates belonged to the dominant global lineage A (67.2%), while the remainder were either lineage C (19.4%) or F (13.4%). The population structure was relatively homogenous across the country as we did not find any significant lineage distributions between study sites inside or outside Dhaka. Our genomic data showed presence of single point mutations in gyrA gene either at codon 83 or 87 associated with decreased fluoroquinolone susceptibility in all Bangladeshi S. Paratyphi A isolates. Notably, we identified the pHCM2- like cryptic plasmid which was highly similar to S. Typhi plasmids circulating in Bangladesh and has not been previously identified in S. Paratyphi A organisms.SignificanceThis study demonstrates the utility of WGS to monitor the ongoing evolution of this emerging enteric pathogen. Novel insights into the genetic structure of S. Paratyphi A will aid the understanding of both regional and global circulation patterns of this emerging pathogen and provide a framework for future genomic surveillance studies.     

Effects of halogen substitution on Watson–Crick base pairing: A possible mechanism for radiosensitivity

The halogen substituent effect on geometries and charge distributions of the A–T base pair derivatives was evaluated using density functional theory at B3LYP/6-31G1 level. The results indicate that all of the substitutions affect geometries and charge distributions of the atoms contributing hydrogen bonds. These changes would be the reason of the radiosensitization of these compounds incorporating DNA.