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.     

Thermophysical Properties of Short Carbon Fiber/SiC Multilayer Composites Prepared by Tape Casting and Pressureless Sintering

C_sf/SiC multilayer composites for thermal conductivity (TC) test in three directions were successively prepared by tape casting and pressureless sintering. After 1500°C/5 h oxidation treatment, short carbon fibers were oxidized which produced many pores. However, a core area, which was composed by short carbon fiber, SiC, and few SiO₂, was still observed. TC properties of C_sf/SiC multilayer composites were highly anisotropic. The TC was decreased with the increase in fiber amount. C_sf/SiC multilayer composites demonstrated the highest TC along the tape casting direction and the lowest TC through the thickness direction, which is favorable for thermal protection purpose.     

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.     

Polymerase chain reaction-based analysis to detect terrestrial animal protein in fish meal

The recent European bovine spongiform encephalopathy crisis has focused attention on the importance of adopting stringent control measures to avoid the risk of the diffusion of mad cow disease through meat meal-based animal feedstuffs. Potential adulteration of such feedstuffs with bone particles from terrestrial animals is determined by microscopic examination by law before the release of these feedstuffs for free circulation in the European Community. This study describes a DNA monitoring method to examine fish meal for contamination with mammalian and poultry products. A polymerase chain reaction (PCR) method based on the nucleotide sequence variation in the 12S ribosomal RNA gene of mitochondrial DNA was developed and evaluated. Three species-specific primer pairs were designed for the identification of ruminant, pig, and poultry DNA. The specificity of the primers used in the PCR was tested by comparison with DNA samples for several vertebrate species and confirmed. The PCR specifically detected mammalian and poultry adulteration in fish meals containing 0.125% beef, 0.125% sheep, 0.125% pig, 0.125% chicken, and 0.5% goat. A multiplex PCR assay for ruminant and pig adulteration was optimized and had a detection limit of 0.25%.     

Metformin and Vitamin D Modulate Inflammation and Autophagy during Adipose-Derived Stem Cell Differentiation

Adipose-derived stem cells (ADSCs) came out from the regenerative medicine landscape for their ability to differentiate into several phenotypes, contributing to tissue regeneration both in vitro and in vivo. Dysregulation in stem cell recruitment and differentiation during adipogenesis is linked to a chronic low-grade inflammation and macrophage infiltration inside the adipose tissue, insulin resistance, cardiovascular disease and obesity. In the present paper we aimed to evaluate the role of metformin and vitamin D, alone or in combination, in modulating inflammation and autophagy in ADSCs during adipogenic commitment. ADSCs were cultured for 21 days in the presence of a specific adipogenic differentiation medium, together with metformin, or vitamin D, or both. We then analyzed the expression of FoxO1 and Heat Shock Proteins (HSP) and the secretion of proinflammatory cytokines IL-6 and TNF-α by ELISA. Autophagy was also assessed by specific Western blot analysis of ATG12, LC3B I, and LC3B II expression. Our results showed the ability of the conditioned media to modulate adipogenic differentiation, finely tuning the inflammatory response and autophagy. We observed a modulation in HSP mRNA levels, and a significant downregulation in cytokine secretion. Taken together, our findings suggest the possible application of these molecules in clinical practice to counteract uncontrolled lipogenesis and prevent obesity and obesity-related metabolic disorders.     

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.     

Evidence for Diffusion-Controlled Hydrocarbon Selectivities in the Fischer�CTropsch Synthesis Over Cobalt Supported on Ordered Mesoporous Silica

A series of four cobalt-based catalysts (two of which promoted with ruthenium) supported on SiO₂ or SBA-15 were prepared and tested in the Fischer?CTropsch synthesis at industrially relevant process conditions (483 K, 20 bar, H₂/CO ratio = 2.1, pellet size: 53?C90 ??m). The catalysts were characterized by N₂-adsorption, X-ray diffraction (XRD), temperature-programmed reduction (TPR), H₂-chemisorption and transmission electron microscopy (TEM). Ru as promoter enhanced the activity but not the selectivity to long-chain hydrocarbons ( $ {\text{S}}_{{{\text{C}}_{ 5+ } }} $ ). The $ {\text{S}}_{{{\text{C}}_{ 5+ } }} $ values of the SBA-supported catalysts were very low, especially at low conversion levels (i.e. low water partial pressure), suggesting that CO diffusion limitation increased the H₂/CO ratio inside the 1-dimensional (1-D) porous network. A superimposition of the selectivity results on the correlations found in our recent study, derived for Co-based catalysts supported on ??-Al₂O₃, ??-Al₂O₃ and TiO₂ free from diffusion limitations, was made. While the SiO₂-supported catalysts with a 3-D porous structure followed the correlations, the SBA-catalysts deviated significantly at low conversions, giving a further indication that the selectivity results of these catalysts were affected by CO diffusion limitations. Hence, it may be concluded that the kinetically significant diffusion distances (i.e. those long enough to cause an intrapore H₂/CO ratio higher than that of the bulk gas phase) are probably much shorter for 1-D porous networks than for conventional 3-D supports. This is explained by a significantly lower effective diffusivity in 1-D porous networks. The potential of using the correlations between non-ASF distributed hydrocarbons and C₅₊, to give insight on the occurrence of diffusion limitations, was confirmed by superimposing data from the literature that were anticipated to be influenced by CO diffusion limitations.     

HE4 in the Differential Diagnosis of a Pelvic Mass: A Case Report

Neoplasms of the ovary present an increasing challenge to the physician. Neoplastic ovarian cysts can resemble endometriomas in ultrasound imaging and need to be carefully considered in the differential diagnosis. We report the case of a woman with a strong family history of hereditary breast and ovarian cancer, who presented with a pelvic mass. The young girl refused oncogenetic counseling and genetic testing, even though she had a 50% a priori probability of being a BRCA1 mutation carrier. Pelvic magnetic resonance imaging (MRI) and a comparative analysis of the serum concentration of HE-4 and CA125 biomarkers provided accuracy and sensitivity in the diagnosis of a benign ovarian pathology. Based on this experience, we propose that the sensitivity of a screening program based on a HE4 and CA125 assay and MRI in high risk patients with mutations in the BRCA1 and BRCA2 genes may be considered a useful pre-operative tool for the differential diagnosis of pelvic masses.