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Global warming, as a result of an increase in the mean temperature of the planet, might lead to catastrophic events for humanity. This temperature increase is mainly the result of an increase in the atmospheric greenhouse gases (GHG) concentration. Water vapor, carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O) are the most important GHG, and human activities, such as industry, livestock and agriculture, contribute to the production of these gases. Methane, at an atmospheric concentration of 1.7 μmol mol−1currently, is responsible for 16% of the global warming due to its relatively high global warming potential. Soils play an important role in the CH4cycle as methanotrophy (oxidation of CH4) and methanogenesis (production of CH4) take place in them. Understanding methanogenesis and methanotrophy is essential to establish new agriculture techniques and industrial processes that contribute to a better balance of GHG. The current knowledge of methanogenesis and methanotrophy in soils, anaerobic CH4oxidation and methanotrophy in extreme environments is also discussed.

Porphyromonas gingivalises un microorganismo fuertemente asociado con la etiología de la periodontitis. Esta bacteria posee varios factores de virulencia, dentro de los que destacan las gingipaínas, debido a sus múltiples acciones relacionadas con la destrucción de la matriz extracelular del tejido conectivo periodontal, la modulación del sistema inmune del hospedero y la estimulación de la expresión de citoquinas pro-inflamatorias. Estas proteinasas tienen afinidades específicas siendo Arg-gingipaínas (RgpA y RgpB, codificadas por los genes rgpAy rgpB, respectivamente) y Lys-gingipaínas (Kgp, codificada por el gen kgp). Se ha descrito que existen polimorfismos en los genes que codifican para esta proteinasas. El objetivo del presente estudio fue describir la frecuencia de los genotipos identificados para los genes rgpAy kgpen aislados clínicos de P. gingivalis, obtenidos desde pacientes con periodontitis. Para ello se utilizó amplificación por PCR de los genes rgpAy kgp, seguido de análisis de restricción. De un total de 47 aislados provenientes de 4 individuos con periodontitis crónica y 2 con periodontitis agresiva, se genotipificaron 38 aislados para el gen rgpA, exhibiendo la totalidad de éstos el patrón electroforético A (100%). Para el gen kgpse genotipificaron 43 aislados, presentando 28 de ellos (65.2%) el perfil electroforético kgp-Iy 15 aislados (34.8%) el perfil kgp-II. En los aislados provenientes de un individuo fue posible apreciar ambos genotipos descritos para el gen kgp. Los resultados indican un predominio del patrón electroforético A (rgpA) y que el genotipo kgp-Ifue el más frecuentemente encontrado de los genotipos kgp.

Uno de los campos de interés en el estudio de la microbiología periodontal para muchos investigadores ha sido identi car si es posible que los microorganismos responsables del origen y progresión de la enfermedad periodontal que habitan sobre el margen gingival (supragingival) y bajo este (subgingival) tengan una relación directa que permita mantener interacciones influyentes en el crecimiento y desarrollo de las diferentes especies bacterianas que habitan en los tejidos periodontales. Por lo tanto, al remover los microorganismos que se ubican supragingivalmente sería posible encontrar cambios en el medio subgingival al no existir un intercambio entre los ambientes aerobios (supragingival) y anaerobios (subgingival) una vez desorganizada la placa bacteriana supragingival.

In the past 3 years, genome-wide association studies have identified many tens of common genetic variants associated with metabolic diseases and traits. Although much further research is needed to identify the target genes, the associations between gene variants and diseases are already providing biological insights. The purpose of this review is to update the reader with the most relevant findings, with a particular emphasis on type 2 diabetes (T2D) and glucose metabolism, and discuss some of the biological implications of the genetic findings.

(Abstracted from JAMA2016;315(11):1129–1140)Neonates born to overweight or obese women are more likely to be large for gestational age. It has been noted that maternal obesity-related traits are observationally associated with birth weight; however, the causal nature of these associations is uncertain.

Porphyromonas gingivalises un bacilo Gram-negativo y anaerobio, considerado como el mayor agente causal en la iniciación y progresión de las periodontitis. Este microorganismo presenta diversos factores de virulencia, como su capacidad de adherencia a los tejidos periodontales y a otras bacterias orales, el Lipopolisacárido (LPS) que induce la respuesta inmune del hospedero y la acción de múltiples proteasas. Las bases moleculares de estos mecanismos de virulencia y su relación con la diversidad genética no han sido suficientemente comprendidas aún.

Water and solute transport in the efferent ducts and epididymis are important for the establishment of the appropriate luminal environment for sperm maturation and storage. Aquaporin 9 (AQP9) is the main water channel in the epididymis, but its regulation is still poorly understood. Components of the kinin-kallikrein system (KKS), leading to the production of bradykinin (BK), are highly expressed in the lumen of the male reproductive tract. We report here that the epididymal luminal fluid contains a significant amount of BK (2 nM). RT-PCR performed on epididymal epithelial cells isolated by laser capture microdissection (LCM) showed abundant BK type 2 receptor (Bdkrb2) mRNA expression but no type 1 receptor (Bdkrb1). Double-immunofluorescence staining for BDKRB2 and the anion exchanger AE2 (a marker of efferent duct ciliated cells) or the V-ATPase E subunit, official symbol ATP6V1E1 (a marker of epididymal clear cells), showed that BDKRB2 is expressed in the apical pole of nonciliated cells (efferent ducts) and principal cells (epididymis). Triple labeling for BDKRB2, AQP9, and ATP6V1E1 showed that BDKRB2 and AQP9 colocalize in the apical stereocilia of principal cells in the cauda epididymidis. While uniform Bdkrb2mRNA expression was detected in the efferent ducts and along the epididymal tubule, marked variations were detected at the protein level. BDKRB2 was highest in the efferent ducts and cauda epididymidis, intermediate in the distal initial segment, moderate in the corpus, and undetectable in the proximal initial segment and the caput. Functional assays on tubules isolated from the distal initial segments showed that BK significantly increased AQP9-dependent glycerol apical membrane permeability. This effect was inhibited by BAPTA-AM, demonstrating the participation of calcium in this process. This study, therefore, identifies BK as an important regulator of AQP9.

Standard clinical practice recommends minimal doses of vasoactive drugs during weaning of patients from mechanical ventilation. However, there are currently no clinical data to inform clinicians about whether the use of noradrenaline during weaning predisposes to weaning failure. The objective of this study was to evaluate whether the necessity of the vasopressor noradrenaline in mechanically ventilated patients recovering from septic shock changed the extubation outcome.A total of 656 patients recovering from septic shock on mechanical ventilation were selected from intensive care units in two university hospitals. Patients receiving noradrenaline at the time of weaning and case-controls not taking noradrenaline were matched for age, gender, haemodynamic and ventilatory parameters, aetiology of respiratory failure and APACHE II score. One hundred and forty-five patients who successfully tolerated a spontaneous breathing trial were extubated while on noradrenaline therapy and the reintubation rate was measured.In the noradrenaline group, the mean dose of noradrenaline during initial shock treatment was 0.52±0.29 μg/kg/min and 0.12±0.10 μg/kg/min during weaning. The reintubation rate was 12/63 (19%) in the noradrenaline group and 15/82 (18.3%) in the control group (P=1.00). Intensive care unit mortality was also similar in both groups (10/63, 15.9%) for noradrenaline patients and (11/82, 13.4%) for control patients (P=0.81). Arterial blood gases and ventilatory and haemodynamic parameters were similar in all patients regardless of weaning success.We did not find that the use of noradrenaline at the time of weaning was associated with extubation failure. Low doses of noradrenaline may not preclude weaning from mechanical ventilation.

Las periodontitis son un grupo de patologías que afectan los tejidos de soporte del diente. Diferentes especies de la microbiota subgingival se han asociado con los tipos de periodontitis. El aislamiento de bacilos Gram negativos no fastidiosos en sacos periodontales es un tema importante ya que algunas de estas especies podrían contribuir como causa principal a fracasos de la terapia periodontal. También es un foco de interés ubicar reservorios de estas bacterias como fuente principal de infección del saco periodontal. Así, el objetivo de este trabajo fue determinar la presencia/ausencia de bacilos Gram negativos no fastidiosos en sacos periodontales y en el dorso lingual de un grupo de pacientes chilenos con periodontitis.

We described a case of chronic spinal cystic arachnoiditis after subarachnoid haemorrhage in a 54-year-old woman with a ruptured vertebral artery aneurysm treated by coils. At three months she complained of lumbar pain. At twelve months she presented lower limbs paresthesia then a rapidly bilateral motor deficit. MR showed a spinal arachnoiditis with two compressive cysts. Surgical decompression was inefficient and after three months spinal compression symptoms worsened and MR signs were unchanged.

In the epididymis and vas deferens, the vacuolar H+ATPase (V-ATPase), located in the apical pole of narrow and clear cells, is required to establish an acidic luminal pH. Low pH is important for the maturation of sperm and their storage in a quiescent state. The V-ATPase also participates in the acidification of intracellular organelles. The V-ATPase contains many subunits, and several of these subunits have multiple isoforms. So far, only subunits ATP6V1B1, ATP6V1B2, and ATP6V1E2, previously identified as B1, B2, and E subunits, have been described in the rat epididymis. Here, we report the localization of V-ATPase subunit isoforms ATP6V1A, ATP6V1C1, ATP6V1C2, ATP6V1G1, ATP6V1G3, ATP6V0A1, ATP6V0A2, ATP6V0A4, ATP6V0D1, and ATP6V0D2, previously labeled A, C1, C2, G1, G3, a1, a2, a4, d1, and d2, in epithelial cells of the rat epididymis and vas deferens. Narrow and clear cells showed a strong apical staining for all subunits, except the ATP6V0A2 isoform. Subunits ATP6V0A2 and ATP6V1A were detected in intracellular structures closely associated but not identical to the TGN of principal cells and narrow/clear cells, and subunit ATP6V0D1 was strongly expressed in the apical membrane of principal cells in the apparent absence of other V-ATPase subunits. In conclusion, more than one isoform of subunits ATP6V1C, ATP6V1G, ATP6V0A, and ATP6V0D of the V-ATPase are present in the epididymal and vas deferens epithelium. Our results confirm that narrow and clear cells are well fit for active proton secretion. In addition, the diverse functions of the V-ATPase may be established through the utilization of specific subunit isoforms. In principal cells, the ATP6V0D1 isoform may have a physiological function that is distinct from its role in proton transport via the V-ATPase complex.

Organic–inorganic hybrids incorporating Eu(nta)3·bpy (where nta and bpy stand for 1-(2-naphthyl)-4,4,4-trifluoro-1,3-butanedionate and 2,2′-bipyridine, respectively) were prepared either by acetic acid solvolysis or a conventional hydrolysis sol–gel route. The host framework of these materials, classed as di-ureasil, consists of a siliceous network grafted, through urea cross-linkages, to both ends of poly(ethylene oxide) chains. The resulting Eu(iii)-based di-ureasils were investigated by small angle X-ray scattering, X-ray diffraction, Fourier transform mid-infrared spectroscopy, 29Si and 13C nuclear magnetic resonance, and photoluminescence spectroscopy, with particular attention paid to the effect of the adopted synthesis strategy on the relationship between structure and emission properties. The dimensions and the degree of condensation of the siloxane nanodomains depend noticeably on the synthesis route and the overall emission quantum yield decreases from 15 (conventional hydrolysis) to 6% (solvolysis route). The broad white-light emission typical of the di-ureasil host was not detected here suggesting, therefore, the activation of energy transfer channels between the hybrid host's emitting centres and the Eu(iii) ions. As the first coordination shell of Eu(iii) is essentially independent of the synthesis method employed, the significant decrease in the emission quantum yield for the di-ureasil prepared by acetic acid solvolysis might be explained by the interaction between the hybrid emitting centres and the nta ligand levels, favouring a larger non-radiative transition probability.

We analysed whether markers of cell differentiation and infectivity differed when compared to the parental sensitive strain [NR(Gs)] in an in vitro selected Leishmania strain [NR(Gr)] resistant to Glibenclamide®, an ATP-binding-cassette (ABC)-transporter blocker. The data show that the cell body area was larger in NR(Gr) compared to NR(Gs) and that functional characters associated with an infective metacyclic phenotype, such as resistance to the lytic effect of the alternative complement pathway and expression of the Meta-1 protein, were reduced. The infectivity of NR(Gr) to J774.1 macrophages was also significantly reduced. These results suggest that resistance in Leishmania against Glibenclamide®, a general blocker of P-glycoproteins, could produce functional modifications that may be relevant for Leishmania differentiation, infectivity and survival.

In reaction control thrusters (RCT) propulsed space vehicles the force and/or torque derived from the control law must be translated into thrusters selection and thrusters firing durations. This has often to be done in an optimal way with respect to propellant consumption. Classical catalogue approaches to perform that rely on RCT architectural geometry symmetry properties. When such symmetries are not present at all, use of algorithms such as the linear programming “simplex” one has been advocated. But it presents some risks because the computation duration is not deterministic and no converged solution is granted in a predetermined duration. In-house studies performed at EADS Space Transportation found an optimal catalogue solution for the six DOF (degrees of freedom) problem. This algorithm has been developed for the ATV (Automated Transfer Vehicle) spacecraft. It is based on a precomputed optimal catalogue that is used onboard. However this catalogue depends on the centre of mass and this feature prevents its direct use in the pure attitude control problem. Here it is proposed an adaptation of the 6 DOF optimal catalogue to cope with 3 DOF problems and present some results

Urea and urethane cross-linked hybrids, classed as di-ureasils and di-urethanesils, were prepared through sol−gel derived carboxylic acid solvolysis. The resulting nanohybrids were characterized by X-ray diffraction, mid-infrared spectroscopy, ²⁹Si and ¹³C nuclear magnetic resonance, and photoluminescence spectroscopy and results were compared with those of similar hybrid materials obtained from the conventional sol−gel route. The results indicate a similar structure for the hybrids, independent of the synthesis process used. All the hybrids are efficient room-temperature white-light emitters with emission quantum yields between 6 and 20%. The emission quantum yields of hybrids prepared through carboxylic acid solvolysis are 27−35% higher than those calculated for the di-ureasils and di-urethanesils synthesized via the conventional sol−gel technique. This is attributed to the presence of a larger number of nonbonded NH urea- and urethane-groups in the hybrids prepared by carboxylic acid solvolysis, illustrating the key role played by the synthetic method on the extent and magnitude of hydrogen bonding involving urea and urethane linkages.

In this study, water and eight sanitizing solutions (vinegar at 6, 25, and 50%; acetic acid at 2 and 4%; peracetic acid at 80 ppm, sodium hypochlorite at 200 ppm, and sodium dichloroisocyanurate at 200 ppm) were compared in terms of their effectiveness against the natural microbiota of lettuce. All of the samples were kept in contact with the sanitizing solutions for 15 min, and the effectiveness of a sanitizing agent was evaluated on the basis of the number of decimal reductions of the total aerobic mesophilic count, the mold and yeast count, the total coliform count, and the Escherichia colicount. The average initial levels of these organisms in the samples were 6.94 log10CFU/g for aerobic mesophilic microorganisms, 5.62 log10CFU/g for molds and yeasts, and 3.25 log10CFU/g for total coliforms. Of 10 samples analyzed, only 4 contained E. coli, and the average initial level of this microorganism in these 4 samples was 1.64 log10CFU/g. Salmonellawas not detected in any of the samples tested. The decimal reductions of the populations of aerobic mesophilic microorganisms, molds and yeasts, total coliforms, and E. coliwere 0.78, 0.87, 0.82, and >0.14 log10CFU/g, respectively, in water; 2.89, >3.41, >2.21, and >0.26 log10CFU/g, respectively, in 50% vinegar; 2.42, >3.20, >1.99, and >0.26 log10CFU/g, respectively, in 25% vinegar; 1.83, 2.57, 1.58, and >0.26 log10CFU/g, respectively, in 6% vinegar; 3.91, >3.58, >2.25, and >0.26 log10CFU/g, respectively, in 4% acetic acid; 3.37, >3.53, >2.25, and >0.26 log10CFU/g, respectively, in 2% acetic acid; 1.85, 2.32, 1.44, and >0.20 log10CFU/g, respectively, in 80 ppm of peracetic acid; 2.63, 2.75, 1.91, and >0.26 log10CFU/g, respectively, in 200 ppm of sodium hypochlorite; and 3.23, >3.08, >1.95, and >0.26 log10CFU/g, respectively, in 200 ppm of sodium dichloroisocyanurate. Statistical analysis of the results showed that the effectiveness levels for all of the sanitizing agents tested were equivalent to or higher than that for sodium hypochlorite at 200 ppm.

Abstract In order to obtain further information on the structural organization of the cuticle of nematodes, this structure was isolated from adult forms of the filariid Litomosoides chagasfilhoi. The purity of the fraction was determined by light and transmission electron microscopy, deep-etching, high resolution scanning electron microscopy, atomic force microscopy, immunocytochemistry, gel electrophoresis (SDS-PAGE) and Western blot. The epicuticle presented a rugous surface with parallel rows and several globular particles that could be involved in the absorption of nutrients and secretion of products. Analysis by SDS-PAGE of purified cuticles revealed five major polypeptides corresponding to 151, 41, 28, 13 and 11 kDa. A polyclonal antibody against a synthetic 18 amino-acid peptide that corresponds to the sequence of domain E of the Haemonchus contortus 3A3 collagen gene recognized several protein bands on the Western blot of purified cuticle, and labeled all cuticular layers, as shown by immunocytochemistry.

Colour development in fruit of Actinidia chinensis var. chinensis 'Hort16A', the new yellow-fleshed cultivar produced commercially in New Zealand, was monitored during three seasons in four kiwifruit-producing districts of New Zealand. Fruit were destructively harvested to measure flesh colour between flowering and harvest. Flesh colour of the outer pericarp remained green (115° hue angle) until c. 140 days after mid bloom (DAMB). Then flesh colour changed following a sigmoid like pattern to a yellow hue (97-100° hue angle) by 220 DAMB. The change in hue angle is shown to be well represented by the complementary log-log function. The scale parameter describing this transition was independent of site and season, whereas timing of the transition between the upper and lower asymptote was dependant on both site and season because of a small dependence on the average of the maximum temperature over the period of 100-150 DAMB. Each degree C increase in maximum temperature during the 100-150 DAMB delays colour development by c. 3 days. Distribution of individual hue angles about the mean value was best described by a constrained beta distribution defined by two parameters, which in turn uniquely specify the average hue angle and variance of the population at that time. For hue angles near the mid range, which occurs before harvest maturity, this beta distribution is well approximated by a Normal distribution with the same mean and variance, but at harvest maturity a beta distribution is a better description. When the average hue angle is 103°, the difference between the 97.5 percentile on the Normal approximation and the beta distribution is c. 0.6. This difference rises rapidly as the hue angle drops further.