Dissemination of methicillin-resistant Staphylococcus aureus USA300 sequence type 8 lineage in Latin America.

BACKGROUND: Methicillin-resistant Staphylococus aureus (MRSA) is an important nosocomial and community-associated (CA) pathogen. Recently, a variant of the MRSA USA300 clone emerged and disseminated in South America, causing important clinical problems. METHODS: S. aureus isolates were prospectively collected (2006-2008) from 32 tertiary hospitals in Colombia, Ecuador, Peru, and Venezuela. MRSA isolates were subjected to antimicrobial susceptibility testing and pulsed-field gel electrophoresis and were categorized as health care-associated (HA)-like or CA-like clones on the basis of genotypic characteristics and detection of genes encoding Panton-Valentine leukocidin and staphylococcal cassette chromosome (SCC) mec IV. In addition, multilocus sequence typing of representative isolates of each major CA-MRSA pulsotype was performed, and the presence of USA300-associated toxins and the arcA gene was investigated for all isolates categorized as CA-MRSA. RESULTS: A total of 1570 S. aureus were included; 651 were MRSA (41%)--with the highest rate of MRSA isolation in Peru (62%) and the lowest in Venezuela (26%)--and 71%, 27%, and 2% were classified as HA-like, CA-like, and non-CA/HA-like clones, respectively. Only 9 MRSA isolates were confirmed to have reduced susceptibility to glycopeptides (glycopeptide-intermediate S. aureus phenotype). The most common pulsotype (designated ComA) among the CA-like MRSA strains was found in 96% of isolates, with the majority (81%) having a \u3c or =6-band difference with the USA300-0114 strain. Representative isolates of this clone were sequence type 8; however, unlike the USA300-0114 strain, they harbored a different SCCmec IV subtype and lacked arcA (an indicator of the arginine catabolic mobile element). CONCLUSION: A variant CA-MRSA USA300 clone has become established in South America and, in some countries, is endemic in hospital settings

Casimir-like tunneling-induced electronic forces

We study the quantum forces that act between two nearby conductors due to electronic tunneling. We derive an expression for these forces by calculating the flux of momentum arising from the overlap of evanescent electronic fields. Our result is written in terms of the electronic reflection amplitudes of the conductors and it has the same structure as Lifshitz's formula for the electromagnetically mediated Casimir forces. We evaluate the tunneling force between two semiinfinite conductors and between two thin films separated by an insulating gap. We discuss some applications of our results.Comment: 8 pages, 3 figs, submitted to Proc. of QFEXT'05, to be published in J. Phys.

Molecular Line Emission Towards High-Mass Clumps: The MALT90 Catalogue

The Millimetre Astronomy Legacy Team 90 GHz (MALT90) survey aims to characterise the physical and chemical evolution of high-mass clumps. Recently completed, it mapped 90 GHz line emission toward 3246 high-mass clumps identified from the ATLASGAL 870 �m Galactic plane survey. By utilising the broad frequency coverage of the Mopra telescope's spectrometer, maps in 16 different emission lines were simultaneously obtained. Here we describe the �first line catalog of the detected emission, generated by Gaussian profile �fitting to spectra extracted toward each clumps' dust peak. Synthetic spectra show that the catalog has a completeness of >95%, a probability of a false-positive detection of <0.3%, and a relative uncertainty in the measured quantities of <20% over the range of detection criteria. We find that the detection rates are highest for the (1{0) molecular transitions of HCO+, HNC, N2H+, and HCN (72{88%). The majority of clumps (~� 95%) are detected in at least one of the molecular transitions, just under half of the clumps (�~48%) are detected in 4 or more of the transitions, while only 2 clumps are detected in 13 or more transitions. We find several striking trends in the ensemble of properties for the different molecular transitions when plotted as a function of the clumps' evolutionary state. In particular, the optically thickest HCO+ emission shows a `blue-red asymmetry' that indicates overall collapse that monotonically decreases as the clumps evolve. This catalog represents the largest compiled database of molecular line emission toward high-mass clumps and is a valuable data set for detailed studies of these objects

Nutrientes y productividad primaria fitoplanctónica en una laguna costera tropical intermitente (La Mancha, Ver.) del Golfo de México

In the coastal lagoon of La Mancha, the effect of the sand barriers opening implies that the lagoon loses along this period (157 days), 1148,400 m3 of their original volume; when the barrier closes, the increment of water toward the interior of the system is calculated in approximately 950, 400 m3 reaching 1 663, 200 m3 . When the lagoon remained communicated with the sea (from June 23 to November 25 , the measured parameters showed the following medians values: salinity 22.0 ups, disolved oxygen 3.33 ml/l, pH 7.3 units; the concentrations of ammonia 7.24 µM; nitrates plus nitrite 0.6 µM, while phosphates registered 8.66 µM; like consequence N:P ratio was below to 1 (0.78), this means P&gt;N; chlorophyll a reach 11.30 mg/m3 and primary productivity quantities was low (29.84 mgC/m3 /h) this causes a drop in C:Chl ratio of 2.50 mgCm3 hr:mg-1m-3.During the period when the lagoon is isolated, salinity showed a descent (16.5 ups), as same as the concentration of dissolved oxygen (2.58 ml/l); pH was lightly higher (7.58 units); the ammonia was 8.47 µM and was detected a slight increment in the nitrates plus nitrite (1.65 µM), contrarily there was a decrease in phosphates (5.73 µM), this cause that N:P ratio increased lightly to 1.77; chlorophyll a diminished to 3.04 mg/m3 , contrarily there was a significant increment of the primary productivity (158.63 mgC/m3 /h), the above-mentioned brought gets a greater value of the C:Chl ratio (28.09 mgCm3 hr:mg-1m-3).En el caso de la laguna de La Mancha, el efecto de la apertura de la boca implica que la laguna pierda, a lo largo de este período (157 días) 1148,400 m3 de su volumen original; cuando la boca se cierra, el incremento de agua hacia el interior del sistema se calcula en aproximadamente 950,400 m3 alcanzando 1 663,200 m3 . Cuando la laguna permaneció comunicada con el mar (del 23 de junio al 25 de noviembre), los parámetros medidos mostraron las siguientes medianas: la salinidad de 22.0 ups, el oxígeno disuelto 3.33 ml/l, el pH 7.3 unidades; las concentraciones de amonio 7.24 µM; los nitratos más nitritos 0.6 µM, mientras que los fosfatos registraron 8.66 µM, como consecuencia la relación N:P fue menor a 1 (0.78), esto es P&gt;N; clorofila a registró 11.30 mg/m3 y una baja productividad primaria (29.84 mgC/m3 /h) lo que con llevó a una relación C:Clor a de apenas 2.50 mgCm3 hr:mg-1m-3. En cambio, cuando la laguna se encuentra incomunicada, la salinidad manifestó un descenso (16.5 ups), igualmente que la concentración de oxígeno (2.58 ml/l); el pH fue ligeramente mayor (7.58 unidades); el amonio fue de 8.47 µM y se detectó un ligero incremento en los nitratos más nitritos (1.65 µM), contrariamente hubo una disminución en los fosfatos (5.73 µM), por lo que la relación N:P aumentó ligeramente a 1.77; la clorofila a disminuyó a 3.04 mg/m3 , contrariamente hubo un incremento de la productividad primaria (158.63 mgC/m3 /h), lo anterior trajo consigo un valor mayor de la relación C:Clor a (28.09 mgCm3 hr:mg-1m-3)

MALT90 Kinematic Distances to Dense Molecular Clumps

Using molecular-line data from the Millimetre Astronomy Legacy Team 90 GHz Survey (MALT90), we have estimated kinematic distances to 1905 molecular clumps identified in the ATLASGAL 870 μm continuum survey over the longitude range 295° < l < 350°. The clump velocities were determined using a flux-weighted average of the velocities obtained from Gaussian fits to the HCO+, HNC, and N2H+ (1–0) transitions. The near/far kinematic distance ambiguity was addressed by searching for the presence or absence of absorption or self-absorption features in 21 cm atomic hydrogen spectra from the Southern Galactic Plane Survey. Our algorithm provides an estimation of the reliability of the ambiguity resolution. The Galactic distribution of the clumps indicates positions where the clumps are bunched together, and these locations probably trace the locations of spiral arms. Several clumps fall at the predicted location of the far side of the Scutum–Centaurus arm. Moreover, a number of clumps with positive radial velocities are unambiguously located on the far side of the Milky Way at galactocentric radii beyond the solar circle. The measurement of these kinematic distances, in combination with continuum or molecular-line data, now enables the determination of fundamental parameters such as mass, size, and luminosity for each clump

Pathophysiological Role of Genetic Factors Associated With Gestational Diabetes Mellitus

Gestational Diabetes Mellitus (GDM) is a highly prevalent maternal pathology characterized by maternal glucose intolerance during pregnancy that is, associated with severe complications for both mother and offspring. Several risk factors have been related to GDM; one of the most important among them is genetic predisposition. Numerous single nucleotide polymorphisms (SNPs) in genes that act at different levels on various tissues, could cause changes in the expression levels and activity of proteins, which result in glucose and insulin metabolism dysfunction. In this review, we describe various SNPs; which according to literature, increase the risk of developing GDM. These SNPs include: (1) those associated with transcription factors that regulate insulin production and excretion, such as rs7903146 (TCF7L2) and rs5015480 (HHEX); (2) others that cause a decrease in protective hormones against insulin resistance such as rs2241766 (ADIPOQ) and rs6257 (SHBG); (3) SNPs that cause modifications in membrane proteins, generating dysfunction in insulin signaling or cell transport in the case of rs5443 (GNB3) and rs2237892 (KCNQ1); (4) those associated with enzymes such as rs225014 (DIO2) and rs9939609 (FTO) which cause an impaired metabolism, resulting in an insulin resistance state; and (5) other polymorphisms, those are associated with growth factors such as rs2146323 (VEGFA) and rs755622 (MIF) which could cause changes in the expression levels of these proteins, producing endothelial dysfunction and an increase of pro-inflammatory cytokines, characteristic on GDM. While the pathophysiological mechanism is unclear, this review describes various potential effects of these polymorphisms on the predisposition to develop GDM

SEDIGISM: Structure, excitation, and dynamics of the inner Galactic interstellar medium

The origin and life-cycle of molecular clouds are still poorly constrained, despite their importance for understanding the evolution of the interstellar medium. Many large-scale surveys of the Galactic plane have been conducted recently, allowing for rapid progress in this field. Nevertheless, a sub-arcminute resolution global view of the large-scale distribution of molecular gas, from the diffuse medium to dense clouds and clumps, and of their relationshipto the spiral structure, is still missing. Aims. We have carried out a systematic, homogeneous, spectroscopic survey of the inner Galactic plane, in order to complement the many continuum Galactic surveys available with crucial distance and gas-kinematic information. Our aim is to combine this data set with recent infrared to sub-millimetre surveys at similar angular resolutions. © 2017 ESO

Calcium and temperature effect on structural damage of hot air dried apple slices: Nonlinear irreversible thermodynamic approach and rehydration analysis

Mathematical models traditionally employed in fitting convective drying data do not use to report information about chemical and other physical changes different from the simple decrease in moisture content. In the present study, structural damage undergone by fresh and vacuum impregnated apple slices with different calcium lactate concentrations during convective drying at 30, 40 and 50 °C was analysed by applying equations derived from nonlinear irreversible thermodynamics to experimental data. According to the results obtained, vacuum impregnation with isotonic sucrose solution before drying at 30 °C provided maximum protection to cellular structure by promoting reversible deformations against irreversible breakages. On the contrary, cell walls strengthen with calcium had severe damaged during drying. Regarding air temperature, it was directly related both to the molar energy employed in deforming structures and the drying rate. These results were confirmed by analysing dried samples behaviour during further rehydration.Barrera Puigdollers, C.; Betoret Valls, N.; Betoret Valls, ME.; Fito Maupoey, P. (2016). Calcium and temperature effect on structural damage of hot air dried apple slices: Nonlinear irreversible thermodynamic approach and rehydration analysis. Journal of Food Engineering. 189:106-114. doi:10.1016/j.jfoodeng.2016.05.024S10611418