Homogeneous Catalyzed Direct Conversion of Furfural to Gamma-Valerolactone.

Herein, we report the direct conversion of biomass-derived furfural to γ-valerolactone (GVL) in a one-pot system, using the combination of Ru-MACHO-BH and a Brønsted acid (H3 PO4 ). A GVL yield of 84 % is achieved under mild reaction conditions using 1 mol% of Ru-MACHO-BH and 3.8 M H3 PO4 (aq) at 100 °C for 7 hours.

Base-free, acceptorless dehydrogenative coupling of ethanol to ethyl acetate with PNP complexes.

A base-free, acceptorless dehydrogenative coupling of ethanol to ethyl acetate is presented. By using the pincer complex (PhPNP)RuH(BH4)(CO) (0.25 mol%) in the presence of m-xylene as the co-solvent, the catalysis proceeds with up to >99% conversion and >99% yield after 24 h at 120 °C. A scaled-up reaction is also effective under similar conditions.

Versatile CO2 Hydrogenation-Dehydrogenation Catalysis with a Ru-PNP/Ionic Liquid System.

High catalytic activities of Ru-PNP [Ru = ruthenium; PNP = bis alkyl- or aryl ethylphosphinoamine complexes in ionic liquids (ILs) were obtained for the reversible hydrogenation of CO2 and dehydrogenation of formic acid (FA) under exceedingly mild conditions and without sacrificial additives. The novel catalytic system relies on the synergic combination of Ru-PNP and IL and proceeds with CO2 hydrogenation already at 25 °C under a continuous flow of 1 bar of CO2/H2 (1:5), leading to 14 mol % FA with respect to the IL. A pressure of 40 bar of CO2/H2 (1:1) provides 126 mol % of FA/IL corresponding to a space-time yield (STY) of FA of 0.15 mol L-1 h-1. The conversion of CO2 contained in imitated biogas was also achieved at 25 °C. Furthermore, the Ru-PNP/IL system catalyzes FA dehydrogenation with average turnover frequencies up to 11,000 h-1 under heat-integrated conditions for proton-exchange membrane fuel cell applications (<100 °C). Thus, 4 mL of a 0.005 M Ru-PNP/IL system converted 14.5 L FA over 4 months with a turnover number exceeding 18,000,000 and a STY of CO2 and H2 of 35.7 mol L-1 h-1. Finally, 13 hydrogenation/dehydrogenation cycles were achieved with no sign of deactivation. These results demonstrate the potential of the Ru-PNP/IL system to serve as a FA/CO2 battery, a H2 releaser, and a hydrogenative CO2 converter.

Development and validation of a UHPLC-ESI-QTOF mass spectrometry method to analyze opines, plant biomarkers of crown gall or hairy root diseases.

Opines are low-molecular-weight metabolites specifically biosynthesized by agrobacteria-transformed plant cells when plants are struck by crown gall and hairy root diseases, which cause uncontrolled tissue overgrowth. Transferred DNA is sustainably incorporated into the genomes of the transformed plant cells, so that opines constitute a persistent biomarker of plant infection by pathogenic agrobacteria and can be targeted for crown gall/hairy root disease diagnosis. We developed a general, rapid, specific and sensitive analytical method for overall opine detection using ultra-high-performance liquid chromatography-electrospray ionization quadrupole time-of-flight mass spectrometry (UHPLC-ESI-MS-QTOF), with easy preparation of samples. Based on MS, MS/MS and chromatography data, the detection selectivity of a wide range of standard opines was validated in pure solution and in different plant extracts. The method was successfully used to detect different structural types of opines, including opines for which standard compounds are unavailable, in tumors or hairy roots induced by pathogenic strains. As the method can detect a wide range of opines in a single run, it represents a powerful tool for plant gall analysis and crown gall/hairy root disease diagnosis. Using an appropriate dilution of plant extract and a matrix-based calibration curve, the quantification ability of the method was validated for three opines belonging to different families (nopaline, octopine, mannopine), which were accurately quantified in plant tissue extracts.

Impact of Paraburkholderia phytofirmans PsJN on Grapevine Phenolic Metabolism.

Phenolic compounds are implied in plant-microorganisms interaction and may be induced in response to plant growth-promoting rhizobacteria (PGPRs). Among PGPR, the beneficial bacterium Paraburkholderia phytofirmans PsJN was previously described to stimulate the growth of plants and to induce a better adaptation to both abiotic and biotic stresses. This study aimed to investigate the impact of PsJN on grapevine secondary metabolism. For this purpose, gene expression (qRT-PCR) and profiling of plant secondary metabolites (UHPLC-UV/DAD-MS QTOF) from both grapevine root and leaves were compared between non-bacterized and PsJN-bacterized grapevine plantlets. Our results showed that PsJN induced locally (roots) and systemically (leaves) an overexpression of PAL and STS and specifically in leaves the overexpression of all the genes implied in phenylpropanoid and flavonoid pathways. Moreover, the metabolomic approach revealed that relative amounts of 32 and 17 compounds in roots and leaves, respectively, were significantly modified by PsJN. Once identified to be accumulated in response to PsJN by the metabolomic approach, antifungal properties of purified molecules were validated in vitro for their antifungal effect on Botrytis cinerea spore germination. Taking together, our findings on the impact of PsJN on phenolic metabolism allowed us to identify a supplementary biocontrol mechanism developed by this PGPR to induce plant resistance against pathogens.

Differential Contribution of Plant-Beneficial Functions from Pseudomonas kilonensis F113 to Root System Architecture Alterations in Arabidopsis thaliana and Zea mays.

Fluorescent pseudomonads are playing key roles in plant-bacteria symbiotic interactions due to the multiple plant-beneficial functions (PBFs) they are harboring. The relative contributions of PBFs to plant-stimulatory effects of the well-known plant growth-promoting rhizobacteria Pseudomonas kilonensis F113 (formerly P. fluorescens F113) were investigated using a genetic approach. To this end, several deletion mutants were constructed, simple mutants ΔphlD (impaired in the biosynthesis of 2,4-diacetylphloroglucinol [DAPG]), ΔacdS (deficient in 1-aminocyclopropane-1-carboxylate deaminase activity), Δgcd (glucose dehydrogenase deficient, impaired in phosphate solubilization), and ΔnirS (nitrite reductase deficient), and a quadruple mutant (deficient in the four PBFs mentioned above). Every PBF activity was quantified in the wild-type strain and the five deletion mutants. This approach revealed few functional interactions between PBFs in vitro. In particular, biosynthesis of glucose dehydrogenase severely reduced the production of DAPG. Contrariwise, the DAPG production impacted positively, but to a lesser extent, phosphate solubilization. Inoculation of the F113 wild-type strain on Arabidopsis thaliana Col-0 and maize seedlings modified the root architecture of both plants. Mutant strain inoculations revealed that the relative contribution of each PBF differed according to the measured plant traits and that F113 plant-stimulatory effects did not correspond to the sum of each PBF relative contribution. Indeed, two PBF genes (ΔacdS and ΔnirS) had a significant impact on root-system architecture from both model plants, in in vitro and in vivo conditions. The current work underscored that few F113 PBFs seem to interact between each other in the free-living bacterial cells, whereas they control in concert Arabidopsis thaliana and maize growth and development.

Activation of aldehydes by exocyclic iridium(i)-η4:π2-diene complexes derived from 1,3-oxazolidin-2-ones.

The Ir(i) complexes [TpMe2Ir(η4-1,4-diene)] 2b and 2c react thermally with a variety of aromatic aldehydes, 3a-e, to generate the metallabicyclic compounds 4e-k and the Fischer-type carbenes 5a-b in moderate yields. These reactions are proposed to take place with the initial formation of η1-aldehyde adducts as key intermediates. The formation of the metallabicyclic compounds 4e-k involves a formal decarboxylation process at the exo-2-oxazolidinone diene and an ortho metallation of the aromatic ring. The generation of the Fischer-type carbenes 5a-b is the result of a series of metal-based rearranged intermediates with no decarboxylation observed. Treatment of the η4-diene complex 2b with a variety of Lewis bases induces a change in the binding mode of the diene ligand from η4:π2 to η2:σ2 to form the Ir(iii) derivatives 6b-d of composition TpMe2Ir-(η4:π2-1,4-diene)(L) (L = CO, MeCN, and C5H5N). A study of reactions of complex 2b with either mono- or poly-deuterated aldehydes was performed to understand the mechanisms of such processes. The results of these studies were used to determine plausible formation mechanisms of the metallabicyclic compounds 4e-4k and Fischer-type carbenes 5a-b compound series. These mechanisms were corroborated by density functional theory (DFT) calculations of the free energy profiles.

Synthesis, structure and reactivity of group 4 corrole complexes.

A series of early transition metal corrole complexes has been prepared via salt metathesis with the corresponding lithium corrole. Their characterization by single crystal X-ray diffraction, NMR, and absorption spectroscopy is described. Organometallic derivatives of the titanium complex were obtained via treatment of 2 with NaCp* or ClMgCH2SiMe3.

Unusual activation of H2 by reduced cobalt complexes supported by a PNP pincer ligand.

The reactivity of cobalt complexes supported by a PNP pincer ligand towards H2 varies depending on whether the N-donor atom is protonated; the synthesis of [(HPNP)CoCl(H)2] (2), [(PNP)CoH]2 (4), and the trihydride species [(HPNP)CoH3] (7) (HPNP = HN(CH2CH2P(i)Pr2)2) are described.

Chemistry of reduced monomeric and dimeric cobalt complexes supported by a PNP pincer ligand.

The reduction chemistry of cobalt complexes with HPNP (HPNP = HN(CH2CH2P(i)Pr2)2) as a supporting ligand is described. Reaction of [(HPNP)CoCl2] (1) with n-BuLi generated both the deprotonated Co(II) species [(PNP)CoCl] (2) along with the Co(I) complex [(HPNP)CoCl] (3). Products resulting from reduction of 2 with KC8 vary depending upon the atmosphere under which the reduction is performed. Monomeric square planar [(PNP)CoN2] (4) is obtained under dinitrogen, whereas dimeric [(PNP)Co]2 (5) is formed under argon. Over time, 5 activates a C-H bond in the PNP ligand to form the species [Co(H)(µ-PNP)(µ-(i)Pr2PCH2CH2NCHCH2P(i)Pr2)Co] (6). We also observed the oxidative addition of H-Si bond to complex 3 to form [(HPNP)CoCl(H)SiH2Ph] (7). (1)H NMR studies showed that species 7 is in equilibrium with 3 and silane in solution. Complex 3 can be oxidized with AgBPh4 to generate {(HPNP)CoCl}BPh4 (8), a square planar species with a formal electron count of 15 electrons.

Personality disorders in child sexual abuse victims.

The main aim of the present study is to offer an updated review of the international studies published on personality disorders in child sexual abuse victims. The different papers were classified according to the most frequently found topics regarding this issue, with special focus on antisocial personality disorder and borderline personality disorder. The studies reviewed provide inconclusive results, which demonstrate the need for longitudinal studies that could test the directionality of the relationship between child sexual abuse, personality traits, and personality disorders. The concept of resilience is emphasized in order to explain the interindividual differences that are found in victims of the same traumatic event.

Guía de bioseguridad para laboratorios clínicos / Biosecurity Guidelines for Clinical Labortatories

Vías de infección.- Clasificación de laboratorios.- Procedimientos de seguridad.- Manejo de muestras biológicas.- Limpieza y desinfección.- Accidentes de trabajo.- Manejo de desechos.- Recursos humanos y físicos.- Bioética y control de calidad

Leishmania cutánea: a propósito de un caso clínico / Cutaneous leishmania: with regard to a clinical case

Analiza que la Leishmania es una antropozoonosis de amplia distribución geográfica en nuestro país, que compromete a la mayor parte de las provincias (clima tropical y subtropical), hasta los 1500 metros sobre el nivel del mar, enfermedad transmitida por moscas (flebotomos-lutzomia) a partir de huésped, mamíferos. Su período de incubación es amplio desde pocos días a varios meses y su presentación clínica es muy diversa. En nuestro país predomina las formas de Leishmania Cutánea y Leishmania Mucocutánea, siendo más frecuente en hombres, por su ocupación o trabajos en el campo (cazadores, pescadores, empleados forestales, etc). No obstante se presenta en mujeres como nuestro caso. En el Centro de Salud No. 1 de la ciudad de Riobamba, acude una paciente de sexo femenino de 32 años, por presentar una lesión en la cara anterior de la pierna derecha, la misma que tiene un período de evolución de 4 meses tiempo en el cual ha recibido varios tratamientos antibióticos y antiinflamatorios, sin ninguna mejora. En su anamnesis se desprende que hace 5 meses y estando de viaje a la costa recibe picadura de insecto en el sitio de la lesión. Se realiza el diagnóstico clínico y de laboratorio y se instala el tratamiento con antimoniacales hasta el tercer día, por presentar el paciente hipersensibilidad a éste, se le cambia a un medicamente alterno (Metronidazol) con evolución muy favorable. Relatamos este caso por considerar que una anamnesis, un diagnóstico y tratamiento precoz y correcto, reducirá las secuelas cicatrizales y psicológicas en inmuerables ocasiones.

Prevalencia de cesáreas en el Hospital Pablo Arturo Suárez de la ciudad de Quito 1996 / Prevalencia of Caesarean in the Hospital Pablo Arturo Suárez the city of Quito 1996

Presenta une studio de tripo retrospectivo, para valorar la prevalencia de cesáreas en el Hospital Pablo Arturo Suárez de la ciudad de Quito, entre ene. a dic. de 1996. Se atendió en esta unidad operativa, un total de 2003 partos de los cuales se registró un total de 380 pacientes a quienes se les prescribió y realizó la intervención cesárea, se determinó una tasa de prevalencia de 18.97xcto. En relación a la edad materna se determinó que el 92.11xcto (n=350) de pacientes correspondieron a los no adolescentes, y el 7.89xcto (N=30) correspondieron a los adolescentes. La mayor prevalencia de cesáreas según la paridad fue en multíparas con el 64.2xcto (n=224). La etiología de la cesárea fue debido a: Cesárea anterior en el 29.5xcto (n=11), desproporción cefalopélvico en el 22.6xcto (n=86) y el sufrimiento fetal agudo en el 10xcto (n=38), confirmándose que las cesáreas están indicadas en caso de riesgos fetal y materno. Se observó que el mayor porcentaje de casos fueron en embarazos a término en el 85.5xcto (n=325) y pretérmino 5.23xcto (n=20). El tipo de anestesia fue raquídea en el 52.8xcto (n=201) y peridural en el 38.65xcto (n=147).

Complicaciones de la anestesia raquidea en el Hospital Pablo Arturo Suárez 1995 / Complications of the rachidian anesthesia in the Hospital Pablo Artuto Suárez Hospital 1995

Presenta un estudio longitudinalmente prospectivo de las complicaciones de la práctica de anestesia raquídea en el Hospital Pablo Arturo Suárez de Quito. Se analizan un total de 130 pacientes quirúrgicos entre mar. a jul. 1995. Se pudo encontrar los siguientes hallazgos: 1. Sexo femenino 35.15xciento, masculino 63.84xciento. 2. Tipos de cirugía: Ginecológica 19.16xciento, general 34.04xciento, traumatología 46.8xciento. 3. Altura de punción en mujeres DXII-LI 0xciento. Varones. D XII-LI 1.2xciento. L II-L III 19.27xciento y L IV-L V 3.61xciento. Efectos colaterales en mujeres: Hipotensión 13.24xciento. Bradicardia 14.45xciento, técnica inadecuada 3.62xciento. Dolor tipo corriente 7.22xciento Otros 13.26xciento. Otros 48.2xciento.