Antimicrobial Effect of 7-O-Butylnaringenin, a Novel Flavonoid, and Various Natural Flavonoids against Helicobacter pylori Strains

Abstract: The antimicrobial effect of a novel flavonoid (7-O-butylnaringenin) on Helicobacter pylori 26695, 51, and SS1 strains and its inhibitory effect on the urease activity of the strains were evaluated and compared with those of several natural flavonoids. First, various flavonoids were screened for antimicrobial activities using the paper disc diffusion method. Hesperetin and naringenin showed the strongest antimicrobial effects among the natural flavonoids tested, and thus hesperetin and naringenin were selected for comparison with 7-O-butylnaringenin. The antimicrobial effect of 7-O-butylnaringenin was greater than that of the hesperetin and naringenin. H. pylori 51 was more sensitive to 7-O-butylnaringenin (2 log reduction of colony forming units, p \u3c 0.05) than the other two strains at 200 μM. 7-O-Butylnaringenin also showed the highest inhibitory effect against urease activity of H. pylori. Morphological changes of H. pylori 26695 treated with these flavonoids indicated that both hesperetin and 7-O-butylnaringenin at 200 μM damaged the cell membranes

Intracellular consequences of SOS1 deficiency during salt stress

A mutation of AtSOS1 (Salt Overly Sensitive 1), a plasma membrane Na+/H+-antiporter in Arabidopsis thaliana, leads to a salt-sensitive phenotype accompanied by the death of root cells under salt stress. Intracellular events and changes in gene expression were compared during a non-lethal salt stress between the wild type and a representative SOS1 mutant, atsos1-1, by confocal microscopy using ion-specific fluorophores and by quantitative RT-PCR. In addition to the higher accumulation of sodium ions, atsos1-1 showed inhibition of endocytosis, abnormalities in vacuolar shape and function, and changes in intracellular pH compared to the wild type in root tip cells under stress. Quantitative RT-PCR revealed a dramatically faster and higher induction of root-specific Ca2+ transporters, including several CAXs and CNGCs, and the drastic down-regulation of genes involved in pH-homeostasis and membrane potential maintenance. Differential regulation of genes for functions in intracellular protein trafficking in atsos1-1 was also observed. The results suggested roles of the SOS1 protein, in addition to its function as a Na+/H+ antiporter, whose disruption affected membrane traffic and vacuolar functions possibly by controlling pH homeostasis in root cells

Genome structures and transcriptomes signify niche adaptation for the multiple-ion-tolerant extremophyte Schrenkiella parvula

Schrenkiella parvula (formerly Thellungiella parvula), a close relative of Arabidopsis (Arabidopsis thaliana) and Brassica crop species, thrives on the shores of Lake Tuz, Turkey, where soils accumulate high concentrations of multiple-ion salts. Despite the stark differences in adaptations to extreme salt stresses, the genomes of S. parvula and Arabidopsis show extensive synteny. S. parvula completes its life cycle in the presence of Na+, K+, Mg2+, Li+, and borate at soil concentrations lethal to Arabidopsis. Genome structural variations, including tandem duplications and translocations of genes, interrupt the colinearity observed throughout the S. parvula and Arabidopsis genomes. Structural variations distinguish homologous gene pairs characterized by divergent promoter sequences and basal-level expression strengths. Comparative RNA sequencing reveals the enrichment of ion-transport functions among genes with higher expression in S. parvula, while pathogen defense-related genes show higher expression in Arabidopsis. Key stress-related ion transporter genes in S. parvula showed increased copy number, higher transcript dosage, and evidence for subfunctionalization. This extremophyte offers a framework to identify the requisite adjustments of genomic architecture and expression control for a set of genes found in most plants in a way to support distinct niche adaptation and lifestyles. © 2014 American Society of Plant Biologists. All rights reserved

A novel phase variant of the cholera pathogen shows stress-adaptive cryptic transcriptomic signatures

© 2016 The Author(s). Background: In a process known as phase variation, the marine bacterium and cholera pathogen Vibrio cholerae alternately expresses smooth or rugose colonial phenotypes, the latter being associated with advanced biofilm architecture and greater resistance to ecological stress. To define phase variation at the transcriptomic level in pandemic V. cholerae O1 El Tor strain N16961, we compared the RNA-seq-derived transcriptomes among the smooth parent N16961, its rugose derivative (N16961R) and a smooth form obtained directly from the rugose at high frequencies consistent with phase variation (N16961SD). Results: Differentially regulated genes which clustered into co-expression groups were identified for specific cellular functions, including acetate metabolism, gluconeogenesis, and anaerobic respiration, suggesting an important link between these processes and biofilm formation in this species. Principal component analysis separated the transcriptome of N16961SD from the other phase variants. Although N16961SD was defective in biofilm formation, transcription of its biofilm-related vps and rbm gene clusters was nevertheless elevated as judged by both RNA-seq and RT-qPCR analyses. This transcriptome signature was shared with N16961R, as were others involving two-component signal transduction, chemotaxis, and c-di-GMP synthesis functions. Conclusions: Precise turnarounds in gene expression did not accompany reversible phase transitions (i.e., smooth to rugose to smooth) in the cholera pathogen. Transcriptomic signatures consisting of up-regulated genes involved in biofilm formation, environmental sensing and persistence, chemotaxis, and signal transduction, which were shared by N16961R and N16961SD variants, may implicate a stress adaptation in the pathogen that facilitates transition of the N16961SD smooth form back to rugosity should environmental conditions dictate

Trans-Sacral Epiduroscopic-Assisted 1,414-nm Nd:YAG Laser Decompression for Lumbar Discal Cyst: A Report of 9 Cases

Prevalence of lumbar discal cyst is very low, it can cause low back pain and radiating leg pain when present. Currently, trans-sacral epiduroscopic-assisted, 1,414-nm Nd:YAG laser decompression (SELD) is commonly used for spinal pathologies. However, the use of the laser for spinal procedures can be limited due to the risk of thermal injury. We reviewed nine consecutive patients who underwent SELD ablation for discal cyst between 2014 and 2015. Each patient underwent diagnostic imaging, including simple radiographs, computed tomography with discography, and magnetic resonance imaging (MRI). Pain relief and clinical outcome assessment of patient satisfaction was the primary outcome measure. All patients presented with back pain and unilateral radiating pain. The discal cyst was located in the lumbar region in all patients. Preoperative MRI showed a connection between the cyst and the involved intervertebral disc. All patients obtained immediate relief of symptoms after the discal cyst was treated with a SELD-assisted, 1,414-nm Nd:YAG laser. The mean visual analogue scale (VAS) for back pain was 7.89±0.78 preoperatively, 1.67±1.50 at the 1-month follow up, and 0.38±0.5 at the final follow up (p<0.01). All patients obtained excellent or good outcomes according to the modified MacNab's criteria. There were no complications. These cases demonstrated that trans-sacral, epiduroscopic-assisted, 1,414-nm Nd:YAG laser decompression was a safe, viable, and efficacious option for treating lumbar discal cyst because it lowers the risk of muscle injury and can be performed under local anesthesia

Effects of Textural Properties on the Response of a SnO2-Based Gas Sensor for the Detection of Chemical Warfare Agents

The sensing behavior of SnO2-based thick film gas sensors in a flow system in the presence of a very low concentration (ppb level) of chemical agent simulants such as acetonitrile, dipropylene glycol methyl ether (DPGME), dimethyl methylphosphonate (DMMP), and dichloromethane (DCM) was investigated. Commercial SnO2 [SnO2(C)] and nano-SnO2 prepared by the precipitation method [SnO2(P)] were used to prepare the SnO2 sensor in this study. In the case of DCM and acetonitrile, the SnO2(P) sensor showed higher sensor response as compared with the SnO2(C) sensors. In the case of DMMP and DPGME, however, the SnO2(C) sensor showed higher responses than those of the SnO2(P) sensors. In particular, the response of the SnO2(P) sensor increased as the calcination temperature increased from 400 °C to 800 °C. These results can be explained by the fact that the response of the SnO2-based gas sensor depends on the textural properties of tin oxide and the molecular size of the chemical agent simulant in the detection of the simulant gases (0.1–0.5 ppm)