Effect of surface roughness and sterilization on bacterial adherence to ultra-high molecular weight polyethylene

AbstractSterilization with ethylene oxide (EO) and gas plasma (GP) are well-known methods applied to ultra-high molecular weight polyethylene (UHMWPE) surfaces in the belief that they prevent major material changes caused by gamma irradiation. However, the influence of these surface sterilization methods on bacterial adherence to UHMWPE is unknown. UHMWPE samples with various degrees of roughness (0.3, 0.8 and 2.0 µm) were sterilized with either GP or EO. The variations in hydrophobicity, surface free energy and surface functional groups were investigated before and after sterilization. Sterilized samples were incubated with either Staphylococcus aureus or Staphylococcus epidermidis in order to study bacterial adherence to these materials. Fewer bacteria adhered to UHMWPE after sterilization with EO than after sterilization with GP, especially to the smoothest surfaces. No changes in chemical composition of the UHMWPE surface due to sterilization were observed using X-ray photoemission spectroscopy analysis. The decreased bacterial adherence to UHMWPE found at the smoothest surfaces after sterilization with EO was not directly related to changes in chemical composition. Increased bacterial adherence to rougher surfaces was associated with increased polar surface energy of EO-sterilized surfaces

Manufacturing Methods Based on Planar Circuits

Manufacture of hybrid 3D-planar circuits, especially those incorporating empty waveguides on substrates, can benefit from most standardized planar fabrication processes, although they are not exactly the same. For this reason, planar circuit manufacturing methods must be adapted to the requirements of these new circuits. Through numerous fabrications and successful designs, several enhancing strategies have been established to improve all the manufacturing phases to achieve better results. They all have been proved in the following substrate-integrated technologies for the manufacturing of microwave devices: ESIW, ESICL, continuous profile, and microstrip. Thanks to these improvements, good-quality prototypes such as transitions, filters, circulators, couplers, antennas, among others, have been fabricated. Throughout the next chapter, these strategies applied along the manufacturing process will be explained: from the first manufacturing phase to the final welding of the whole circuit and taking into account external elements such as wires that may be present in these structures. For this purpose, some devices that have been published will be used as examples

Bridging the gap between molecular and elemental mass spectrometry: Higher energy collisional dissociation (HCD) revealing elemental information

Molecular mass spectrometry has been applied to simultaneously obtain molecular and elemental information from metal-containing species. Energy tuning of the higher-energy collision dissociation (HCD) fragmentation cell allows the controlled production of typical peptide fragments or elemental reporter ions informing about the metallic content of the analyzed species. Different instrumental configurations and fragmentation techniques have been tested, and the efficiency extracting the elemental information has been compared. HCD fragmentation operating at very high energy led to the best results. Platinum, lanthanides, and iodine reporter ions from peptides interacting with cisplatin, peptides labeled with lanthanides-MeCAT-IA, and iodinated peptides, respectively, were obtained. The possibility to produce abundant molecular and elemental ions in the same analysis simplifies the correlation between both signals and open pathways in metallomics studies enabling the specific tracking of metal-containing species. The proposed approach has been successfully applied to in solution standards and complex samples. Moreover, interesting preliminary MALDI-imaging experiments have been performed showing similar metal distribution compared to laser ablation (LA)-ICPMS

Distribución espacial y controles ambientales de las represas (tajamares) en el Chaco Árido

Las regiones áridas tienen déficit hídrico a lo largo de todo el año, lo cual limita el crecimiento de la vegetación y la provisión de agua para bebida animal. El Chaco Árido (~10 Mha) sostiene una producción ganadera extensiva de baja inversión, basada en cosechar agua de lluvia en represas (tajamares) como principal fuente de abastecimiento de agua. En este trabajo se determinó la distribución espacial de las represas y su relación con el entorno biofísico (precipitación, vegetación, caminos) en el Chaco Árido. Para ello analizamos imágenes satelitales, información vectorial y análisis multivariados sobre una grilla de 135 celdas de 0.25°x0.25° cada una. En total identificamos 7920 represas (1 cada 1230 ha) y observamos densidades máximas de 1 represa cada 185 ha, pero también celdas sin represas, asociadas a la presencia de sierras, salinas y dunas. La densidad de represas fue mayor en celdas con mayor densidad de establecimientos ganaderos, caminos y carga animal (r=0.63, r=0.56 y r=0.51, respectivamente; P<0.01 en todos los casos), y en sitios con mayor precipitación media anual y menor variabilidad interanual (r=0.62 y r=-0.47, respectivamente; P<0.01 para ambos casos). Aunque la precipitación media anual fue el atributo que mejor se asoció a la distribución de las represas a escala regional, dicha relación fue más variable hacia los extremos del gradiente (árido y subhúmedo). Esto puede deberse a factores antrópicos tales como la baja rentabilidad de los sistemas ganaderos y la historia o el cambio en el uso del suelo. Los resultados de este trabajo representan un primer intento para dimensionar la importancia que tienen las represas en el Chaco Árido. Consideramos que este estudio puede ser útil para entender la producción ganadera y también para futuras investigaciones relacionadas con la conservación de la vida silvestre y el desarrollo de poblados rurales en la región.Spatial distribution and environmental controls of dams (small impoundments) in the Arid Chaco. Arid regions are characterized by water shortage throughout the year, which constrains both the vegetation growth and the supply of water for livestock consumption. The Arid Chaco (~10 Mha) hosts extensive and low-investment livestock systems based on rainwater harvesting stored in dams (small impoundments) as the main source of water supply. In this study, we characterized the spatial distribution of dams in the Arid Chaco and analyzed their relationship with biophysical variables (e.g. rainfall, vegetation, roads). For these purposes, we used satellite images, vector information and performed multivariate analysis on a spatial grid of 135 cells of 0.25°x0.25°. In total, 7920 dams were identified (1 dam every 1230 ha), with maximum densities of 1 dam every 185 ha but also cells without dams associated with the presence of mountains, salt flats and dunes. Dam density was higher in cells with higher densities of livestock establishments, roads and cale stock (r=0.63, r=0.56 and r=0.51, respectively; P<0.01 in all cases), and in cells with higher mean annual rainfall and lower interannual rainfall variability (r=0.62 and r=-0.47, respectively; P<0.01 for both cases). Although the mean annual rainfall was the best-associated variable with the distribution of dams at the regional scale, this relationship weakened towards the extremes of the gradient (arid and sub-humid). This may be due to anthropic factors such as the low profitability of livestock systems, the previous land uses or land-use changes. The results of this study represent a first aempt to assess the importance of impoundments in the Arid Chaco. We believe that this study may be useful not only to understand livestock production, but also for future studies related to the conservation of wildlife and the development of rural towns in the region.Instituto de Investigación Animal del Chaco SemiáridoFil: Niborski, Marcos J. Universidad Nacional de San Luis. Grupo de Estudios Ambientales-IMASL. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Niborski, Marcos J. Universidad de Buenos Aires. Facultad de Agronomía. Cátedra de Manejo y Conservación de Suelos; ArgentinaFil: Murray, Francisco. Instituto Nacional de Tecnología Agropecuaria (INTA). Estación Experimental Agropecuaria San Luis. Agencia De Extensión Rural San Luis; ArgentinaFil: Jobbágy, Esteban G. Universidad Nacional de San Luis. Grupo de Estudios Ambientales-IMASL. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nosetto, Marcelo D. Universidad Nacional de San Luis. Grupo de Estudios Ambientales-IMASL. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Nosetto, Marcelo D. Universidad Nacional de Entre Ríos. Facultad de Ciencias Agropecuarias. Cátedra de Climatología; ArgentinaFil: Fernandez, Pedro David. Instituto Nacional de Tecnología Agropecuaria (INTA). Instituto de Investigación Animal del Chaco Semiárido; ArgentinaFil: Fernandez, Pedro David. Universidad Nacional de Tucumán. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Ecología Regional (IER); ArgentinaFil: Castellanos, George. Universidad Nacional de San Luis. Grupo de Estudios Ambientales-IMASL. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Magliano, Patricio N. Universidad Nacional de San Luis. Grupo de Estudios Ambientales-IMASL. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Magliano, Patricio N. Universidad Nacional de San Luis. Facultad de Química, Bioquímica y Farmacia. Departamento de Biología; Argentin

CD98hc facilitates B cell proliferation and adaptive humoral immunity.

The proliferation of antigen-specific lymphocytes and resulting clonal expansion are essential for adaptive immunity. We report here that B cell-specific deletion of the heavy chain of CD98 (CD98hc) resulted in lower antibody responses due to total suppression of B cell proliferation and subsequent plasma cell formation. Deletion of CD98hc did not impair early B cell activation but did inhibit later activation of the mitogen-activated protein kinase Erk1/2 and downregulation of the cell cycle inhibitor p27. Reconstitution of CD98hc-deficient B cells with CD98hc mutants showed that the integrin-binding domain of CD98hc was required for B cell proliferation but that the amino acid-transport function of CD98hc was dispensable for this. Thus, CD98hc supports integrin-dependent rapid proliferation of B cells. We propose that the advantage of adaptive immunity favored the appearance of CD98hc in vertebrates

Sublayer- and cell-type-specific neurodegenerative transcriptional trajectories in hippocampal sclerosis

Altres ajuts: Fundación Tatiana Pérez de Guzman el Bueno; SynCogDis Network (SAF2014-52624-REDT, SAF2017-90664-REDT); Human Frontiers Science Program (HFSP RGP0022/2013); Fondo Europeo de Desarrollo Regional (FEDER).Hippocampal sclerosis, the major neuropathological hallmark of temporal lobe epilepsy, is characterized by different patterns of neuronal loss. The mechanisms of cell-type-specific vulnerability and their progression and histopathological classification remain controversial. Using single-cell electrophysiology in vivo and immediate-early gene expression, we reveal that superficial CA1 pyramidal neurons are overactive in epileptic rodents. Bulk tissue and single-nucleus expression profiling disclose sublayer-specific transcriptomic signatures and robust microglial pro-inflammatory responses. Transcripts regulating neuronal processes such as voltage channels, synaptic signaling, and cell adhesion are deregulated differently by epilepsy across sublayers, whereas neurodegenerative signatures primarily involve superficial cells. Pseudotime analysis of gene expression in single nuclei and in situ validation reveal separated trajectories from health to epilepsy across cell types and identify a subset of superficial cells undergoing a later stage in neurodegeneration. Our findings indicate that sublayer- and cell-type-specific changes associated with selective CA1 neuronal damage contribute to progression of hippocampal sclerosis

Epidemiology, patterns of care, and mortality for patients with acute respiratory distress syndrome in intensive care units in 50 countries

IMPORTANCE: Limited information exists about the epidemiology, recognition, management, and outcomes of patients with the acute respiratory distress syndrome (ARDS). OBJECTIVES: To evaluate intensive care unit (ICU) incidence and outcome of ARDS and to assess clinician recognition, ventilation management, and use of adjuncts-for example prone positioning-in routine clinical practice for patients fulfilling the ARDS Berlin Definition. DESIGN, SETTING, AND PARTICIPANTS:The Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG SAFE) was an international, multicenter, prospective cohort study of patients undergoing invasive or noninvasive ventilation, conducted during 4 consecutive weeks in the winter of 2014 in a convenience sample of 459 ICUs from 50 countries across 5 continents. EXPOSURES:Acute respiratory distress syndrome. MAIN OUTCOMES AND MEASURES: The primary outcome was ICU incidence of ARDS. Secondary outcomes included assessment of clinician recognition of ARDS, the application of ventilatory management, the use of adjunctive interventions in routine clinical practice, and clinical outcomes from ARDS. RESULTS: Of 29,144 patients admitted to participating ICUs, 3022 (10.4%) fulfilled ARDS criteria. Of these, 2377 patients developed ARDS in the first 48 hours and whose respiratory failure was managed with invasive mechanical ventilation. The period prevalence of mild ARDS was 30.0% (95% CI, 28.2%-31.9%); of moderate ARDS, 46.6% (95% CI, 44.5%-48.6%); and of severe ARDS, 23.4% (95% CI, 21.7%-25.2%). ARDS represented 0.42 cases per ICU bed over 4 weeks and represented 10.4% (95% CI, 10.0%-10.7%) of ICU admissions and 23.4% of patients requiring mechanical ventilation. Clinical recognition of ARDS ranged from 51.3% (95% CI, 47.5%-55.0%) in mild to 78.5% (95% CI, 74.8%-81.8%) in severe ARDS. Less than two-thirds of patients with ARDS received a tidal volume 8 of mL/kg or less of predicted body weight. Plateau pressure was measured in 40.1% (95% CI, 38.2-42.1), whereas 82.6% (95% CI, 81.0%-84.1%) received a positive end-expository pressure (PEEP) of less than 12 cm H2O. Prone positioning was used in 16.3% (95% CI, 13.7%-19.2%) of patients with severe ARDS. Clinician recognition of ARDS was associated with higher PEEP, greater use of neuromuscular blockade, and prone positioning. Hospital mortality was 34.9% (95% CI, 31.4%-38.5%) for those with mild, 40.3% (95% CI, 37.4%-43.3%) for those with moderate, and 46.1% (95% CI, 41.9%-50.4%) for those with severe ARDS. CONCLUSIONS AND RELEVANCE: Among ICUs in 50 countries, the period prevalence of ARDS was 10.4% of ICU admissions. This syndrome appeared to be underrecognized and undertreated and associated with a high mortality rate. These findings indicate the potential for improvement in the management of patients with ARDS

Results of noninvasive ventilation in very old patients

International audienceABSTRACT: BACKGROUND: Noninvasive ventilation (NIV) is frequently used for the management of acute respiratory failure (ARF) in very old patients (>80 years), often in the context of a do-not-intubate order (DNI). We aimed to determine its efficacy and long-term outcome. METHODS: Prospective cohort of all patients admitted to the medical ICU of a tertiary hospital during a 2-year period and managed using NIV. Characteristics of patients, context of NIV, and treatment intensity were compared for very old and younger patients. Six-month survival and functional status were assessed in very old patients. RESULTS: During the study period, 1,019 patients needed ventilatory support and 376 (37%) received NIV. Among them, 163 (16%) very old patients received ventilatory support with 60% of them managed using NIV compared with 32% of younger patients (p < 0.0001). Very old patients received NIV more frequently with DNI than in younger patients (40% vs. 8%). Such cases were associated with high mortality for both very old and younger patients. Hospital mortality was higher in very old than in younger patients but did not differ when NIV was used for cardiogenic pulmonary edema or acute-on-chronic respiratory failure (20% vs. 15%) and in postextubation (15% vs. 17%) out of a context of DNI. Six-month mortality was 51% in very old patients, 67% for DNI patients, and 77% in case of NIV failure and endotracheal intubation. Of the 30 hospital survivors, 22 lived at home and 13 remained independent for activities of daily living. CONCLUSIONS: Very old patients managed using NIV have an overall satisfactory 6-month survival and functional status, except for endotracheal intubation after NIV failure

Non-standard interactions versus non-unitary lepton flavor mixing at a neutrino factory

The impact of heavy mediators on neutrino oscillations is typically described by non-standard four-fermion interactions (NSIs) or non-unitarity (NU). We focus on leptonic dimension-six effective operators which do not produce charged lepton flavor violation. These operators lead to particular correlations among neutrino production, propagation, and detection non-standard effects. We point out that these NSIs and NU phenomenologically lead, in fact, to very similar effects for a neutrino factory, for completely different fundamental reasons. We discuss how the parameters and probabilities are related in this case, and compare the sensitivities. We demonstrate that the NSIs and NU can, in principle, be distinguished for large enough effects at the example of non-standard effects in the $\mu$-$\tau$-sector, which basically corresponds to differentiating between scalars and fermions as heavy mediators as leading order effect. However, we find that a near detector at superbeams could provide very synergistic information, since the correlation between source and matter NSIs is broken for hadronic neutrino production, while NU is a fundamental effect present at any experiment.Comment: 32 pages, 5 figures. Final version published in JHEP. v3: Typo in Eq. (27) correcte