Expression Profile of pha Gene Cluster of Pseudomonas putida KT2442

Polyhydroxyalkanoates (PHAs) are biodegradable polymers that many bacteria accumulate as carbon and energy storage when growth conditions are unbalanced. Pseudomonas strains belonging to the rRNA homology group I such as P. putida can accumulate medium-chain-length-PHA from monomers in the C8 to C10 range. Regulation of PHA synthesis and degradation in P. putida KT2442 has been studied using different molecular approaches. In this study six promoter regions located upstream of each pha gene were identified. The expression of the pha cluster have been analysed in the presence of octanoic acid versus glucose in the culture medium. Results demonstrated that the system is activated in the presence of octanoic acid as PHA precursor.     

Dioxomolybdenum(VI) complexes containing N-heterocyclic carbenes

Compound MoO₂Cl₂(THF)₂ reacts with two equivalents of 1,3-dialkyl substituted 4,5-dimethylimidazol-2-ylidenes to give the dioxomolybdenum(VI) complexes MoO₂Cl₂(L^R)₂ [R = Me (1), i-Pr (2)]. Treatment of MoO₂Cl₂(THF)₂ with one equivalent of the N-heterocyclic carbenes L^Me, L^i-Pr and ^C1L^n-Bu (L^Me = 1,3,4,5-tetramethylimidazol-2-ylidene, L^i-Pr = 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene, and ^C1L^n-Bu = 1,3-dibutyl-4,5-dichloroimidazol-2-ylidene) affords the monocarbene adducts MoO₂Cl₂(L^R) [R = Me (3), i-Pr (4)] and MoO₂Cl₂(^C1L^n-Bu) (5), respectively. Decomposition of complexes 1-5 affords a molybdenum oxychloride anion [Mo₂O₅Cl₄]²⁻ as an imidazolium salt.     

An ultrasonic-accelerated oxidation method for determining the oxidative stability of biodiesel

Biodiesel is considered an alternative energy because it is produced from fats and vegetable oils by means of transesterification. Furthermore, it consists of fatty acid alkyl esters (FAAS) which have a great influence on biodiesel fuel properties and in the storage lifetime of biodiesel itself. The biodiesel storage stability is directly related to the oxidative stability parameter (Induction Time – IT) which is determined by means of the Rancimat® method. This method uses condutimetric monitoring and induces the degradation of FAAS by heating the sample at a constant temperature. The European Committee for Standardization established a standard (EN 14214) to determine the oxidative stability of biodiesel, which requires it to reach a minimum induction period of 6 h as tested by Rancimat® method at 110 °C. In this research, we aimed at developing a fast and simple alternative method to determine the induction time (IT) based on the FAAS ultrasonic-accelerated oxidation. The sonodegradation of biodiesel samples was induced by means of an ultrasonic homogenizer fitted with an immersible horn at 480 Watts of power and 20 duty cycles. The UV–Vis spectrometry was used to monitor the FAAS sonodegradation by measuring the absorbance at 270 nm every 2. Biodiesel samples from different feedstock were studied in this work. In all cases, IT was established as the inflection point of the absorbance versus time curve. The induction time values of all biodiesel samples determined using the proposed method was in accordance with those measured through the Rancimat® reference method by showing a R² = 0.998.     

In Vivo Anticancer Activity of AZD3965: A Systematic Review

Proliferating cancer cells have high energy demands, which is mainly obtained through glycolysis. The transmembrane trafficking of lactate, a major metabolite produced by glycolytic cancer cells, relies on monocarboxylate transporters (MCTs). MCT1 optimally imports lactate, although it can work bidirectionally, and its activity has been linked to cancer aggressiveness and poor outcomes. AZD3965, a specific MCT1 inhibitor, was tested both in vitro and in vivo, with encouraging results; a phase I clinical trial has already been undertaken. Thus, analysis of the experimental evidence using AZD3965 in different cancer types could give valuable information for its clinical use. This systematic review aimed to assess the in vivo anticancer activity of AZD3965 either alone (monotherapy) or with other interventions (combination therapy). Study search was performed in nine different databases using the keywords “AZD3965 in vivo” as search terms. The results show that AZD3965 successfully decreased tumor growth and promoted intracellular lactate accumulation, which confirmed its effectiveness, especially in combined therapy. These results support the setup of clinical trials, but other important findings, namely AZD3965 enhanced activity when given in combination with other therapies, or MCT4-induced treatment resistance, should be further considered in the clinical trial design to improve therapy response.     

Thermal behavior of tetradentate Schiff base chromium(III) complexes

Thermal analytical behavior of eight chromium(III) complexes with N,N′-bis(salicylidene)ethylenediamine (salen) Schiff bases, Cr(salen), has been investigated regarding their thermal stability and thermal decomposition pathways. Thus, the ligands and the respective chromium(III) complexes of salen-type Schiff bases derived from salicylaldehyde and its 5-chloro, 5-bromo, 5-methoxy, 5-nitro, 3,5-dicloro, 3,5-dibromo, and 3,5-diiodosalicylaldehyde were synthesized, characterized, and submitted to TG/DTG, DTA, and TG–FTIR evolved gas analysis. The number of steps and, in particular, the starting temperature of decomposition of these complexes was dependent of the ligand nature. The gaseous products evolved during the thermal decomposition of these compounds were identified by TG–FTIR.     

Catalytic enantioselective Reformatsky reaction with ketones

Chiral tertiary alcohols were obtained with good yields and enantioselectivities via a catalytic Reformatsky reaction with ketones, including the challenging diaryl ketones, using chiral BINOL derivatives.     

Hyperbranched polymers versus dendrimers containing a carbosilane framework and terminal ammonium groups as antimicrobial agents

A new family of amine- and ammonium-terminated hyperbranched polycarbosilanes (PCS) and dendrimers has been synthesized. The functionalization of a polycarbosilane matrix was carried out with peripheral allyl groups by two strategies in the case of PCS: 1) hydrosilylation of allyl amines with PCS containing terminal Si-H bonds, or 2) hydrosilylation of PCS-allyl with an aminosilane. Dendrimers with terminal amine groups were synthesized by hydrosilylation of allydimethylamine. Quaternized systems with MeI are soluble and stable in water or other protic solvent. The antibacterial properties of the ammonium-terminated hyperbranched polycarbosilanes and dendrimers have been evaluated showing that they act as potent biocides against Gram-positive and Gram-negative bacterial strains.     

Proposal of a new distribution in PERT methodology

The aim of this paper is to present the generalized biparabolic distribution (GBP) as a good candidate to be utilized as the distribution underlying to PERT methodology (Malcolm et al. in Oper. Res. 7:646–669, 1959). To do this and following the criteria established by Taha (Investigación de Operaciones, 1981) and Herrerías (Estudios de Economía Aplicada, pp. 89–112, 1989), we will compare the mean and variance estimates derived from each proposed density function, viz beta, two-sided power (TSP) and GBP distributions. Also we will compare the estimates contributed by the mesokurtic and of constant variance families of the aforementioned distributions. The main conclusion is that the GBP distribution is the most convenient to be used in the PERT methodology because its mean is almost as moderate as that of trapezoidal and its variance is much higher than that of the rest of distributions. As a consequence, it can be stated that the GBP distribution is an alternative to the other four-parameter distributions.     

Mathematical formulation and validation of the Be-FAST model for Classical Swine Fever Virus spread between and within farms

Classical Swine Fever is a viral disease of pigs that causes severe restrictions on the movement of pigs and pig products in the affected areas. The knowledge of its spread patterns and risk factors would help to implement specific measures for controlling future outbreaks. In this article, we describe in detail a spatial hybrid model, called Be-FAST, based on the combination of a stochastic Individual-Based model (modeling the interactions between the farms, considered as individuals) for between-farm spread with a Susceptible-Infected model for within-farm spread, to simulate the spread of this disease and identify risk zones in a given region. First, we focus on the mathematical formulation of each component of the model. Then, in order to validate Be-FAST, we perform various numerical experiments considering the Spanish province of Segovia. Obtained results are compared with the ones given by two other Individual-Based models and real outbreaks data from Segovia and The Netherlands.