Rhizosphere Bacteria Enhance Selenium Accumulation and Volatilization by Indian Mustard

Indian mustard (Brassica juncea L.) accumulates high tissue Se concentrations and volatilizes Se in relatively nontoxic forms, such as dimethylselenide. This study showed that the presence of bacteria in the rhizosphere of Indian mustard was necessary to achieve the best rates of plant Se accumulation and volatilization of selenate. Experiments with the antibiotic ampicillin showed that bacteria facilitated 35% of plant Se volatilization and 70% of plant tissue accumulation. These results were confirmed by inoculating axenic plants with rhizosphere bacteria. Compared with axenic controls, plants inoculated with rhizosphere bacteria had 5-fold higher Se concentrations in roots (the site of volatilization) and 4-fold higher rates of Se volatilization. Plants with bacteria contained a heat-labile compound in their root exudate; when this compound was added to the rhizosphere of axenic plants, Se accumulation in plant tissues increased. Plants with bacteria had an increased root surface area compared with axenic plants; the increased area was unlikely to have caused their increased tissue Se accumulation because they did not accumulate more Se when supplied with selenite or selenomethionine. Rhizosphere bacteria also possibly increased plant Se volatilization because they enabled plants to overcome a rate-limiting step in the Se volatilization pathway, i.e. Se accumulation in plant tissues.     

Predominance of non-Streptococcus mutans bacteria in dental biofilm and its relation to caries progression

This study aims to assess differences in biofilm bacterial composition between patients with low and high caries. Patients without a medical problem and with no history of antibiotic use, mouth wash or fluoride application in the previous 3 months were recruited. Caries was recorded at cavitation level; score was calculated by a national mean (dmft of 4.8 and DMFT of 2.7). Pooled biofilm samples were collected from mesial, distal, buccal, lingual, and occlusal surfaces. Based on caries experience, individuals were classified into low and high caries and both groups were compared regarding bacteria identified using 16S rRNA gene sequencing, and molecular phylogenetic analysis of the isolates was performed. A total of twenty seven randomly selected samples with low (n = 13) and high (n = 14) caries. Identification of oral bacteria was performed using 16S rRNA sequence, Rothia mucilaginosa and R. aeria were identified in low caries individuals, while R. dentocariosa was detected in high caries individuals. Two Streptococcus spp. were identified only in low caries S. salivarius and S. gordonii whereas S. sanguinis, S. mitis, S. sinensis, S. rubneri, S. vestibularis, S. cristatus and S. massiliensis were identified only in individuals with high caries. This study revealed the absence of R. mucilaginosa in the high caries subjects and its coexistence with the low caries subjects. Streptococcus mutans was insignificant contributor of caries among samples, while, Streptococcus sanguinis was the main constituent of high caries Saudi patients.     

A novel sustainable second-derivative synchronous spectrofluorimetric method for the simultaneous determination of olmesartan medoxomil and rosuvastatin calcium in bulk and formulations: Integrated greenness and whiteness evaluation

The present research has established a quick and highly sensitive second-derivative synchronous fluorometric technique for the simultaneous quantification of a binary mixture of olmesartan medoxomil and rosuvastatin calcium. Simultaneously, the suggested approach was used to detect the synchronous fluorescence intensity of the cited drugs at Δ λ = 80 nm in ethanol to determine the concentrations of olmesartan medoxomil and rosuvastatin calcium at 265 and 240 nm, respectively. Various experimental conditions were tested, and each variable was analyzed and optimized. The calibration graphs were shown to be linear within ranges of 0.1–2.0 and 0.5–6.0 μg ml⁻¹ for each drug concentration, respectively. The newly developed Green Solvents Selecting Tool (GSST) was utilized to assess the solvent's sustainability. Furthermore, the proposed method was found to be environmentally friendly after being evaluated with three different tools [the Green Analytical Procedure Index (GAPI), the Analytical Greenness Metric (AGREE), and the Analytical Eco-Scale with Eco-score equal to 95]. The whiteness qualities were also studied using the Red–Green–Blue (RGB12) model, which was recently designed and showed a high score equal to 92.9. The proposed method’s good findings, as well as its ongoing sustainability, simplicity, and economy, stimulate its application in QC laboratories.     

Reconfigurable RCS Reduction from Curved Structures Using Plasma Based FSS

Plasmonics - The radar cross section (RCS) reduction from curved surfaces using plasma based frequency selective surfaces (FSS) is investigated. A frequency reconfigurable plasma based FSS...     

Herbal plants in the traditional medicine of Bahrain

Plant samples collected in Bahrain and data reported in the literature indicate the flora of Bahrain to contain 52 species (49 genera; 20 families) of medicinal interest. Of these plant species 20 appear to be indigenous and are being used in traditional herbal remedies for numerous afflictions. Preparation of such remedies appears to be simple and includes boiling, infusions, extraction of milled dry or fresh leaves, flowers, seeds or whole plants. Direct consumption of plant parts, raw or cooked, is also practiced. None of these plants has been studied systematically to evaluate their medicinal potential.     

Antimalarial and cytotoxic activities of chiral triamines

Chiral triamine antimalarial compounds have been identified following the screening of mixture-based positional scanning libraries made up of 31,320 compounds against P. falciparum. The library, namely N-methyl triamine (TPI 762) was generated following exhaustive reduction of resin-bound acylated dipeptides. Using the PSCL approach, individual compounds were rapidly identified which were only 10 times less active than the standard drugs chloroquine (CQ) and Artemisinin (Artes).     

Taxonomic characterization of the microorganisms associated with the cultivable diatom Synedra acus from Lake Baikal

Determination of the taxonomic position of microorganisms associated with diatoms was carried out using microscopic, microbiological, and phylogenetic methods. Examination of the cultures of the fresh-water diatom Synedra acus grown in Lake Baikal water by epifluorescence and electron microscopy revealed that bacterial cells colonized the mucilage surrounding the cells of living microalgae and their cell surfaces and penetrate into the frustules of dead diatoms. A total of 13 strains of heterotrophic bacteria were isolated in pure cultures and described. Based on the results of analysis of their morphological, physiological, and biochemical properties, as well as on data obtained by 16S rRNA gene analysis, the following strains were identified to the species level: Sphingomonas sp., Variovorax paradoxus, Pseudomonas fluorescens, Microbacterium trichothecenolyticum, Rhodococcus sp., Caulobacter vibrioides, and Brevundimonas vesicularis.     

Cervicothoracic spinal cord and pontomedullary injury secondary to high-voltage electrocution: a case report

ABSTRACT: INTRODUCTION: High-voltage electrical injuries are uncommonly reported and may predispose to both immediate and delayed neurologic complications. CASE PRESENTATION: We report the case of a 43-year-old Caucasian man who experienced a high-voltage electrocution injury resulting in ischemic myelopathy and secondary paraparesis. CONCLUSION: High-voltage electrocution injuries are a serious problem with potential for both immediate and delayed neurologic sequelae. The existing literature regarding effective treatment of neurologic complications is limited. Long-term follow-up and multidisciplinary management of these patients is required.     

Sensitivity of human pancreatic carcinoma cell line (MIA PaCa-2) to Bisantrene and Theprubicin in vitro

Summary We tested the effect of Bisantrene (BS) and Theprubicin (THP-ADR) on cell growth of a human pancreatic carcinoma cell line (MIA PaCa-2). After 1 h exposure ID₅₀ of BS or THP-ADR was 3×10⁻⁷ and 5×10⁻⁸ M, respectively. Increasing the exposure time from 1 h to continuous exposure for 5d resulted in 11-fold decrease in ID₅₀ for BS and a 6-fold decrease for THP-ADR. Both drugs inhibited [¹⁴C]thymidine incorporation to the same extent and caused an accumulation of cells into G₂+M phase of the cell cycle. This work is supported by a gift, from Mr. Issam Fares and U.S. Public Health Service Grants AM 07114 and CA 19182.