Structure, optical properties and antimicrobial activities of MgO-Bi2-xCrxO3 nanocomposites prepared via solvent-deficient method.

MgO-Bi2-xCrxO3 nanocomposites for x = 0 and 0.07 were fabricated using the solvent-deficient route. X-ray diffraction method, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDXA) and UV-Vis spectroscopy were employed to study the properties. The samples were also evaluated for the antibacterial activity. The x = 0 sample showed a dominant monoclinic crystalline structure of [Formula: see text] phase. No peaks attributed to MgO were observed. Cr-doped [Formula: see text] in which Bi was substituted showed that [Formula: see text] phase was also present in the [Formula: see text] composite. The Scherrer formula was employed to determine the crystallite size of the samples. The Cr-doped sample showed a decrease in the crystallite size. The microstructures of the non-doped MgO-Bi2O3 and MgO-Bi1.93Cr0.07O3 composites consisted of micrometer sized grains and were uniformly distributed. Direct transition energy gap, [Formula: see text] decreased from 3.14 to 2.77 eV with Cr-doping as determined from UV-Vis spectroscopy. The Cr-doped [Formula: see text] nanocomposites exhibited two energy gaps at 2.36 and 2.76 eV. The antibacterial activity was determined against gram-negative bacteria (Salmonella typhimurium and Pseudomonas aeruginosa) and gram-positive bacteria (Staphylococcus aureus) by disc diffusion method. Cr-doping led to a decrease in inhibitory activity of MgO-Bi2-xCrxO3 nanocomposite against the various types of bacteria.

Effect of red thyme oil (Thymus vulgaris L.) vapours on fungal decay, quality parameters and shelf-life of oranges during cold storage.

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.

Ornamental plants on sale to the public are a significant source of pesticide residues with implications for the health of pollinating insects.

Garden centres frequently market nectar- and pollen-rich ornamental plants as "pollinator-friendly", however these plants are often treated with pesticides during their production. There is little information on the nature of pesticide residues present at the point of purchase and whether these plants may actually pose a threat to, rather than benefit, the health of pollinating insects. Using mass spectrometry analyses, this study screened leaves from 29 different 'bee-friendly' plants for 8 insecticides and 16 fungicides commonly used in ornamental production. Only two plants (a Narcissus and a Salvia variety) did not contain any pesticide and 23 plants contained more than one pesticide, with some species containing mixtures of 7 (Ageratum houstonianum) and 10 (Erica carnea) different agrochemicals. Neonicotinoid insecticides were detected in more than 70% of the analysed plants, and chlorpyrifos and pyrethroid insecticides were found in 10% and 7% of plants respectively. Boscalid, spiroxamine and DMI-fungicides were detected in 40% of plants. Pollen samples collected from 18 different plants contained a total of 13 different pesticides. Systemic compounds were detected in pollen samples at similar concentrations to those in leaves. However, some contact (chlorpyrifos) and localised penetrant pesticides (iprodione, pyroclastrobin and prochloraz) were also detected in pollen, likely arising from direct contamination during spraying. The neonicotinoids thiamethoxam, clothianidin and imidacloprid and the organophosphate chlorpyrifos were present in pollen at concentrations between 6.9 and 81 ng/g and at levels that overlap with those known to cause harm to bees. The net effect on pollinators of buying plants that are a rich source of forage for them but simultaneously risk exposing them to a cocktail of pesticides is not clear. Gardeners who wish to gain the benefits without the risks should seek uncontaminated plants by growing their own from seed, plant-swapping or by buying plants from an organic nursery.

Amygdalar hyperactivity, a fear-related link between panic disorder and mesiotemporal epilepsy.

The sudden onset, short duration and stereotyped features of panic attacks, and the fear aura of seizures starting at the mesial aspects of the temporal lobe, suggest common mechanisms underlying panic disorder (PD) and mesiotemporal epilepsy (MTLE). However, current consensus emphasizes the importance of differentiating the two entities based on 1) intact consciousness in panic attacks, 2) poor response to antiepileptics, and 3) unsuccessful electrophysiological attempts to demonstrate a relationship. We report two cases with a diagnosis of PD that had been partially responsive to first line treatments. During the EEG session, both patients developed panic symptoms with minimal EEG changes in response to paper bag-hyperventilation (PB-HV), and several minutes later presented a clear ictal EEG pattern associated with very different clinical symptoms, but both with strong fear content. Z-scored LORETA analysis showed increased current source densities (CSD) at the right amygdala in both subjects during the induced panic symptoms. Several areas were involved during the seizure, different in each subject. Yet, a very significant increase at the amygdala was found in both cases. The LORETA Z-scored source correlation (LSC) analysis also showed similar abnormal patterns during the panic symptoms in both patients, and marked differences during the seizure. These findings show a major role of amygdalar hyperactivity in both fear-related conditions for the two patients, and are discussed in relation to existing models of PD in general. Abnormal overactivation at mesiotemporal regions is poorly represented at the surface recordings but can be detected by the appropriate analytical techniques.

Isolation and characterization of unsymmetrical C(60)Me(5)O(3)H, a cage-opened bisepoxide ketone: tautomerism involving a fullerene cage bond.

Bisepoxide ketone C(60)Me(5)O(3)H, possessing a nine-membered hole in the cage, has been isolated from the reaction of C(60)Cl(6) with methyllithium followed by hydrolysis. It is a tautomer of the recently isolated bisepoxide fullerenol, this tautomerism being the first example involving a cage C-C bond, and may be driven by cage strain. Like the fullerenol, the ketone gives a high C(58)(+) fragmentation ion intensity during EI mass spectrometry.

T-cell receptor gammadelta T-cell leukemia with the morphology of T-cell prolymphocytic leukemia and a postthymic immunophenotype.

T-cell prolymphocytic leukemia (T-PLL) is a postthymic T-cell neoplasm with a characteristic morphology and heterogeneous immunophenotype. Most cases of T-PLL express membrane T-cell receptors (TCRs) of the alphabeta phenotype. We experienced a 30-year-old man suffering from TCRgammadelta T-cell leukemia with morphology compatible to T-PLL with a postthymic phenotype. He was admitted with skin eruption and pancytopenia. Peripheral blood and bone marrow were occupied with medium-sized lymphocytes, which had moderately condensed chromatin with a single nucleolus and sparse, nongranular basophilic cytoplasm. The immunophenotype was CD1a-, CD2-, CD3+, CD4-, CD5+, CD7+, CD8-, and terminal deoxynucleotidyl transferase negative. Hepatosplenomegaly was absent. He was diagnosed as having T-PLL and was treated with combination chemotherapy. Six months later the leukemic cell became chemoresistant. Although the patient showed transient improvement in response to pentostatin, he died 13 months after the diagnosis. To our knowledge, this is the first case of T-PLL with a TCRgammadelta phenotype.

Enzymatic synthesis of 2-beta-D-galactopyranosyloxy ethyl methacrylate (GalEMA) by the thermophilic archeon Sulfolobus solfataricus.

beta-Glycosidases catalyze the synthesis of glycosides when a nucleophilic acceptor other than water is present in the reaction medium. We describe the enzymatyc synthesis of 2-beta-D-galactopyranosyloxyethyl methacrylate (GalEMA) starting from 2-hydroxyethyl methacrylate (HEMA) and p-nitrophenyl-beta-D-galactopyranoside (pNPG) using a beta-glycosidase activity present in the thermophilic archaeon Sulfolobus solfataricus. This thermophilic enzyme catalyzes the transfer of the galactopyranosyl unit from pNPG to the HEMA hydroxyl group by the formation of a new beta-glycosidic bond. The conditions of the biocatalytic system have been optimized to obtain high yield of GalEMA. (c) 1996 John Wiley & Sons, Inc.

Characterization of the reactivity of sulphydryl groups in tryptophanase by a dual-monitoring high-performance liquid chromatographic system with a site-directed fluorescent reagent.

Sulphydryl groups of E. coli tryptophanase (L-tryptophan indole lyase, E.C. 4.1.99.1) were made to react with a fluorescent maleimide derivative, N-(4-anilino-1-naphthyl)maleimide(ANM). By carefully controlling the reaction conditions it was possible to limit the extent of sulphydryl group modification. The modified enzyme was digested with (L-1-tosylamide-2-phenylethyl chloromethyl ketone)-trypsin. The fluorescent peptides obtained were analysed by reversed-phase high-performance liquid chromatography on a C18 column with a dual-monitoring system consisting of a UV and a fluorescence monitor connected in tandem. This was followed by the determination of the amino acid composition of the fluorescent peptides. Comparison of these results with the known, complete primary structure of tryptophanase from the K-12 strain of E. coli allowed the assignment of position 298 to the cysteine residue, which is more selectively modified by ANM under the conditions chosen and is involved in the maintenance of the catalytic activity.

[Adenocarcinoma arising in a bronchial cyst of the mediastinum].

A 39 year-old man with a mediastinal tumor was operated on. After the median sternotomy incision, a mediastinal cyst, which was connected to the right pulmonary hilus with a string, was found. The microscopic examination of the cyst revealed a bronchial cyst with ciliated columunar epithelium and muscle fibers. Adenocarcinoma was found in the mucosa of the cyst. This patient seemed to be the first reported instance of carcinoma in a mediastinal bronchial cyst.