Synthesis,Biological Evaluation and 2D-QSAR Study of Halophenyl Bis-Hydrazones as Antimicrobial and Antitubercular Agents

In continuation of our endeavor towards the development of potent and effective antimicrobial agents, three series of halophenyl bis-hydrazones (14a–n, 16a–d, 17a and 17b) were synthesized and evaluated for their potential antibacterial, antifungal and antimycobacterial activities. These efforts led to the identification of five molecules 14c, 14g, 16b, 17a and 17b (MIC range from 0.12 to 7.81 μg/mL) with broad antimicrobial activity against Mycobacterium tuberculosis; Aspergillus fumigates; Gram positive bacteria, Staphylococcus aureus, Streptococcus pneumonia, and Bacillis subtilis; and Gram negative bacteria, Salmonella typhimurium, Klebsiella pneumonia, and Escherichia coli. Three of the most active compounds, 16b, 17a and 17b, were also devoid of apparent cytotoxicity to lung cancer cell line A549. Amphotericin B and ciprofloxacin were used as references for antifungal and antibacterial screening, while isoniazid and pyrazinamide were used as references for antimycobacterial activity. Furthermore, three Quantitative Structure Activity Relationship (QSAR) models were built to explore the structural requirements controlling the different activities of the prepared bis-hydrazones.     

In Situ Production of Biofunctionalized Few‐Layer Defect‐Free Microsheets of Graphene

Biological interfacing of graphene has become crucial to improve its biocompatibility, dispersability, and selectivity. However, biofunctionalization of graphene without yielding defects in its sp²‐carbon lattice is a major challenge. Here, a process is set out for biofunctionalized defect‐free graphene synthesis through the liquid phase ultrasonic exfoliation of raw graphitic material assisted by the self‐assembling fungal hydrophobin Vmh2. This protein (extracted from the edible fungus Pleurotus ostreatus) is endowed with peculiar physicochemical properties, exceptional stability, and versatility. The unique properties of Vmh2 and, above all, its superior hydrophobicity, and stability allow to obtain a highly concentrated (≈440–510 μg mL^?1) and stable exfoliated material (ζ‐potential, +40/+70 mV). In addition controlled centrifugation enables the selection of biofunctionalized few‐layer defect‐free micrographene flakes, as assessed by Raman spectroscopy, atomic force microscopy, scanning electron microscopy, and electrophoretic mobility. This biofunctionalized product represents a high value added material for the emerging applications of graphene in the biotechnological field such as sensing, nanomedicine, and bioelectronics technologies.     

TCE dechlorination rates, pathways, and efficiency of nanoscale iron particles with different properties

Nanoscale Fe0 particles are a promising technology for in situ remediation of trichloroethene (TCE) plumes and TCE-DNAPL source areas, butthe physical and chemical properties controlling their reactivity are not yet understood. Here, the TCE reaction rates, pathways, and efficiency of two nanoscale Fe0 particles are measured in batch reactors: particles synthesized from sodium borohydride reduction of ferrous iron (Fe/B) and commercially available particles (RNIP). Reactivity was determined under iron-limited (high [TCE]) and excess iron (low [TCE]) conditions and with and without added H2. Particle efficiency, defined as the fraction of the Fe0 in the particles that is used to dechlorinate TCE, was determined under iron-limited conditions. Both particles had a core/shell structure and similar specific surface areas (approximately 30 m2/g). Using excess iron, Fe/B transformed TCE into ethane (80%) and C3-C6 coupling products (20%). The measured surface area normalized pseudo-first-order rate constant for Fe/B (1.4 x 10(-)2 L.h(-1).m(-2) is approximately 4-fold higher than for RNIP (3.1 x 10-(3) L.h(-1).m(-2). All the Fe0 in Fe/B was accessible for TCE dechlorination, and 92 +/- 0.7% of the Fe0 was used to reduce TCE. For Fe/B, H2 evolved from reduction of water (H+) was subsequently used for TCE dechlorination, and adding H2 to the reactor increased both the dechlorination rate and the mass of TCE reduced, indicating that a catalytic pathway exists. RNIP yielded unsaturated products (acetylene and ethene). Nearly half (46%) of the Fe0 in RNIP was unavailable for TCE dechlorination over the course of the experiment and remained in the particles. Adding H2 did not change the reaction rate or efficiency of RNIP. Despite this, the mass of TCE dechlorinated per mass of Fe0 added was similar for both particles due to the less saturated products formed from RNIP. The oxide shell composition and the boron content are the most likely causes for the differences between the particle types.     

Synthesis of Supported Catalysts by Impregnation and Calcination of Low-Temperature Polymerizable Metal-Complexes

The low-temperature polymerizable metal complex solution has been used as an active component precursor to prepare supported (structured) catalysts by a straight-forward sequence of impregnation, drying and calcination. Two typical samples, 5 wt% Zr _x Ce_1?x O₂/Al₂O₃ nanocomposite and structured carbon nanofiber supported Cu?CCeO₂ catalyst, are prepared to explore the potential of this method in the controlled synthesis of catalysts and catalyst supports. The interaction between the active component precursor and the surface of the solid matrices during impregnation and drying is investigated by infrared spectroscopy (IR) and transmission electron microscopy (TEM), demonstrating that the in situ polymerization process is crucial for the deposition of the active component on the surface of solid matrices. The evolution of the phase transformation and the structure of the produced materials during the calcination step is studied by coupling thermal gravimetric analysis?Cdifferential thermal analysis?Cmass spectroscopy (TGA?CDTA?CMS), TEM and X-ray diffraction (XRD) measurements, indicating that higher thermal stable particles or smaller particles can be obtained with the presence of the Al₂O₃ or structured carbon nanofibers (SCNF), respectively, after calcination. This method combines the advantages of sol?Cgel and impregnation, representing a promising route for preparing supported catalysts and catalyst supports. The limitations of the method are also discussed.     

Bioactive xanthones from the roots of Hypericum perforatum (common St John's wort)

BACKGROUND: Extracts of Hypericum perforatum L. (common St John's wort; Hypericaceae) are sold as phytopharmaceuticals and herbal supplements to treat mild to moderate depression and as food additives. Extensively cultivated in Europe, plants can be infected by anthracnose (Colletotrichum gloeosporioides), a virulent fungal pathogen that causes tissue necrosis and dramatically decreases crop value. Such infections triggered the production of new secondary metabolites, specifically xanthones, in cell culture experiments. RESULTS: Bioassay‐guided fractionation of H. perforatum root extracts, testing for growth inhibition of plant pathogenic fungi from the genera Colletotrichum, Botrytis, Fusarium and Phomopsis, was performed. In vitro anti‐inflammatory activity through inhibition of COX‐1, COX‐2 and 5‐LOX‐catalyzed LTB₄ formation was also evaluated. Extracts were analyzed by various chromatographic means and structure elucidation was performed using data from nuclear magnetic resonance and mass spectrometry. CONCLUSION: Researchers have previously described constituents from the aerial parts of this species, but few reports describe secondary metabolites found in underground parts, of particular interest because the lower stem and upper root are often sites of fungal infection. This work resulted in the isolation of three xanthones: 1,6‐dihydroxy‐5‐methoxy‐4′,5′‐dihydro‐4′,4′,5′‐trimethylfurano‐(2′,3′:3,4)‐xanthone; 4,6‐dihydroxy‐2,3‐dimethoxyxanthone; and cis‐kielcorin, one of which possessed novel bioactivity against species of Phomopsis and inhibited 5‐LOX‐mediated LTB₄ formation. Copyright © 2010 Society of Chemical Industry     

Diversity of acetic acid bacteria present in healthy grapes from the Canary Islands

The identification of acetic acid bacteria (AAB) from sound grapes from the Canary Islands is reported in the present study. No direct recovery of bacteria was possible in the most commonly used medium, so microvinifications were performed on grapes from Tenerife, La Palma and Lanzarote islands. Up to 396 AAB were isolated from those microvinifications and identified by 16S rRNA gene sequencing and phylogenetic analysis. With this method, Acetobacter pasteurianus, Acetobacter tropicalis, Gluconobacter japonicus and Gluconacetobacter saccharivorans were identified.However, no discrimination between the closely related species Acetobacter malorum and Acetobacter cerevisiae was possible. As previously described, 16S-23S rRNA gene internal transcribed spacer (ITS) region phylogenetic analysis was required to classify isolates as one of those species. These two species were the most frequently occurring, accounting for more than 60% of the isolates. For typing the AAB isolates, both the Enterobacterial Repetitive Intergenic Consensus (ERIC)-PCR and (GTG)5-PCR techniques gave similar resolution. A total of 60 profiles were identified. Thirteen of these profiles were found in more than one vineyard, and only one profile was found on two different islands (Tenerife and La Palma).     

Detection and quantification of ricin in beverages using isotope dilution tandem mass spectrometry

The toxic plant protein ricin has gained notoriety due to wide availability and potential use as a bioterrorism agent, with particular concern for food supply contamination. We have developed a sensitive and selective mass spectrometry-based method to detect ricin in tap water, 2% milk, apple juice, and orange juice. Ricin added to beverage matrices was extracted using antibody-bound magnetic beads and digested with trypsin. Absolute quantification was performed using isotope dilution mass spectrometry with a linear ion trap operating in product-ion-monitoring mode. The method allows for identification of ricin A chain and B chain and for distinction of ricin from ricin agglutinin within a single analytical run. Ricin-bound beads were also tested for deadenylase activity by incubation with a synthetic ssDNA oligomer. Depurination of the substrate by ricin was confirmed by matrix-assisted laser desorption ionization-time-of-flight mass spectrometry (MALDI-TOFMS). This method was used successfully to extract ricin from each beverage matrix. The activity of recovered ricin was assessed, and quantification was achieved, with a limit of detection of 10 fmol/mL (0.64 ng/mL).     

Implementation of sine condition test to measure optical system misalignments

Rather than measuring aberrations across the field to quantify the alignment of an optical system, we show how a single, on-axis measurement of the pupil mapping can be used to measure the off-axis performance of the system and determine the state of alignment. In this paper we show how the Abbe sine condition can be used to relate the mapping between the entrance and exit pupils to image aberrations that have linear field dependence. This mapping error then can be used to measure the linear astigmatism caused by the misalignment. Additionally, we present experimental results from the sine condition test on a simple system.     

Cognitive behavioral treatment of PTSD in residents of battered women's shelters: Results of a randomized clinical trial.

Objective: This study was designed to explore the acceptability, feasibility, and initial efficacy of a new shelter-based treatment for victims of intimate partner violence (IPV; i.e., Helping to Overcome PTSD through Empowerment [HOPE]). Method: A Phase I randomized clinical trial comparing HOPE (n = 35) with standard shelter services (SSS) (n = 35) was conducted. Primary outcome measures included the Clinician-Administered PTSD Scale (CAPS; D. D. Blake et al., 1995) and the Conflict Tactic Scales-Revised (M. A. Straus, S. L. Hamby, S. Boney-McCoy, & D. B. Sugarman, 1996). Participants were followed at 1-week, 3- and 6-months postshelter. Results: Participants reported HOPE to be credible and indicated a high degree of satisfaction with treatment. Only 2 women withdrew from treatment. Both intent to treat (ITT) and minimal attendance (MA) analyses found that HOPE treatment relative to SSS was significantly associated with a lower likelihood of reabuse over the 6-month follow-up period (OR = 5.1, RR = 1.75; OR = 12.6, RR = 3.12, respectively). Results of hierarchical linear model analyses found a significant treatment effect for emotional numbing symptom severity in the ITT sample, t(67) = ?2.046, p