Regional Variation on Rates of Bronchopulmonary Dysplasia and Associated Risk Factors

Background. An abnormally high incidence (44%) of bronchopulmonary dysplasia with variations in rates among cities was observed in Colombia among premature infants. Objective. To identify risk factors that could explain the observed high incidence and regional variations of bronchopulmonary dysplasia. Study Design. A case-control study was designed for testing the hypothesis that differences in the disease rates were not explained by differences in city-of-birth specific population characteristics or by differences in respiratory management practices in the first 7 days of life, among cities. Results. Multivariate analysis showed that premature rupture of membranes, exposure to mechanical ventilation after received nasal CPAP, no surfactant exposure, use of rescue surfactant (instead of early surfactant), PDA, sepsis and the median daily FIO2, were associated with a higher risk of dysplasia. Significant differences between cases and controls were found among cities. Models exploring for associations between city of birth and dysplasia showed that being born in the highest altitude city (Bogotá) was associated with a higher risk of dysplasia (OR 1.82 95% CI 1.31–2.53). Conclusions. Bronchopulmonary dysplasia was manly explained by traditional risk factors. Findings suggest that altitude may play an important role in the development of this disease. Prenatal steroids did not appear to be protective at high altitude.

(Table 1) Lithology, mineralogy, and physical properties of Cretaceous cherts and porcellanites at DSDP Hole 56-436

Cretaceous chert and porcellanite recovered at Site 436, east of northern Honshu, Japan, are texturally and mineralogically similar to siliceous rocks of comparable age at Sites 303, 304, and 307 in the northwest Pacific. These rocks probably were formed by impregnation of the associated pelagic clay with locally derived silica from biogenic and perhaps some volcanic debris. Fine horizontal laminations are the only primary sedimentary structures, suggesting minimal reworking and transport. Collapse breccias and incipient chert nodules are diagenetic features related to silicification and compaction of the original sediment. Disordered opal-CT (d[101] = 4.09 Å) and microgranular quartz (crystallinity index < 1.0) are the two common silica minerals present. Some samples show quartz replacing this poorly ordered opal- CT, supporting the notion that opal-CT does not become completely ordered (i.e., d[101] = 4.04 Å) in some cases before being converted to quartz. The present temperature calculated for the depth of the shallowest chert and porcellanite at this site is 30 °C; this may represent the temperature of conversion of opal-CT to quartz. High reflection coefficients (0.29-0.65) calculated for the boundary between chert-porcellanite and clay-claystone support the common observation that chert is a strong seismic reflector in deep-sea sedimentary sections.

The impact of a simulated intervention on attitudes of undergraduate nursing and medical students towards end of life care provision

Background: The concerns of undergraduate nursing and medical students’ regarding end of life care are well documented. Many report feelings of emotional distress, anxiety and a lack of preparation to provide care to patients at end of life and their families. Evidence suggests that increased exposure to patients who are dying and their families can improve attitudes toward end of life care. In the absence of such clinical exposure, simulation provides experiential learning with outcomes comparable to that of clinical practice. The aim of this study was therefore to assess the impact of a simulated intervention on the attitudes of undergraduate nursing and medical students towards end of life care.
Methods: A pilot quasi-experimental, pretest-posttest design. Attitudes towards end of life care were measured using the Frommelt Attitudes Towards Care of the Dying Part B Scale which was administered pre and post a simulated clinical scenario. 19 undergraduate nursing and medical students were recruited from one large Higher Education Institution in the United Kingdom.
Results: The results of this pilot study confirm that a simulated end of life care intervention has a positive impact on the attitudes of undergraduate nursing and medical students towards end of life care (p < 0.001).
Conclusions: Active, experiential learning in the form of simulation teaching helps improve attitudes of undergraduate nursing and medical students towards end of life. In the absence of clinical exposure, simulation is a viable alternative to help prepare students for their professional role regarding end of life care.

Murray v McCullough (as Nominee on Behalf of the Trustees and on Behalf of the Board of Governors of Rainey Endowed School) [2016] NIQB 52

Considers the Northern Ireland Queen’s Bench Division ruling in Murray v McCullough concerning the duty of care incumbent upon the school with regard to the wearing of mouth guards by pupils when playing hockey. Comments on the limitations of the legal doctrine of in loco parentis in cases of professional negligence and, how ‘sports law’ jurisprudence might prove instructive in sports negligence cases.

A report on the survey of Lakes Opeta and Bisina to further collect data on presence of Hydrilla verticilata and potential biological control agents

Reports of hydrilla (Hydrilla verticilata) infestation lakes Bisina and Opeta were verbally communicated by some members of FIRRI who undertook surveys during the LVEMP 1 phase (1997 to 2004) to assess the diversity and stocks of fishes in the Kyoga basin satellite lakes. This issue was taken up by FIRRI and NAARI staff who work on aquatic weeds management to ascertain and quantify the presence of H. verticilata and other aquatic weeds, with the sole aim of finding ways and means of controlling one of the world's worst aquatic weeds, H. verticilata.The survey on Lake Opeta indicated that this weed was rare since only a few small broken pieces were sited at the lake's outflow through an extensive wetland to Lake Bisina. It was therefore concluded that it was not economically viable to allocate resources for further survey of H. verticilata on Lake Opeta. This finding therefore discredited the previous (informal) reports that H. verticilata was well established on Lake Opeta. It should be noted that the reports came from scientists who were not well versed with systematics of aquatic plants.

Structural Aspects of the Distinct Biochemical Properties of Glutaredoxin 1 and Glutaredoxin 2 from Saccharomyces cerevisiae

Glutaredoxins (Grxs) are small (9-12 kDa) heat-stable proteins that are ubiquitously distributed. In Saccharomyces cerevisiae, seven Grx enzymes have been identified. Two of them (yGrx1 and yGrx2) are dithiolic, possessing a conserved Cys-Pro-Tyr-Cys motif. Here, we show that yGrx2 has a specific activity 15 times higher than that of yGrx1, although these two oxidoreductases share 64% identity and 85% similarity with respect to their amino acid sequences. Further characterization of the enzymatic activities through two-substrate kinetics analysis revealed that yGrx2 possesses a lower Km for glutathione and a higher turnover than yGrx1. To better comprehend these biochemical differences, the pK(a) of the N-terminal active-site cysteines (Cys27) of these two proteins and of the yGrx2-C30S mutant were determined. Since the pK(a) values of the yGrx1 and yGix2 Cys27 residues are very similar, these parameters cannot account for the difference observed between their specific activities. Therefore, crystal structures of yGrx2 in the oxidized form and with a glutathionyl mixed disulfide were determined at resolutions of 2.05 and 1.91 angstrom, respectively. Comparisons of yGrx2 structures with the recently determined structures of yGrx1 provided insights into their remarkable functional divergence. We hypothesize that the substitutions of Ser23 and Gln52 in yGrx1 by Ala23 and Glu52 in yGrx2 modify the capability of the active-site C-terminal cysteine to attack the mixed disulfide between the N-terminal active-site cysteine and the glutathione molecule. Mutagenesis studies supported this hypothesis. The observed structural and functional differences between yGrx1 and yGrx2 may reflect variations in substrate specificity. (C) 2008 Elsevier Ltd. All rights reserved.

Exploring novel targeted therapeutic strategies against Acute Myeloid Leukemia cells based on inhibition of bromodomain proteins and CDC20 activity

Acute myeloid leukemia (AML) is a haematological malignancies arising from the accumulation of undifferentiated myeloid progenitors with an uncontrolled proliferation. The genomic landscape of AML revealed that the disease is characterized by high level of heterogeneity and is subjected to clonal evolution driven by selective pressure of chemotherapy. In this study, we investigated the therapeutic effects of the inhibition of BRD4 and CDC20 in vitro and ex vivo. We demonstrated that inhibition of BRD4 with GSK1215101A in AML cell lines was effective under hypoxia. It induced the activation of antioxidant response both, at transcriptomic and metabolomic levels, driven by enrichment of NRF2 pathway under normoxic and hypoxic condition. Moreover, the combined treatment with Omaveloxolone, a drug inducing NRF2 activation and NF-κB inhibition, potentiated the effects on apoptosis and colony forming capacity of stem progenitor cells. Lastly, gene expression profiling data revealed that combination treatment induced major changes in genes related to cell cycle, together with enrichment of cell differentiation pathways and negative regulation of WNT, in normoxia and hypoxia. Regarding CDC20, we observed its up-regulation in AML patients. Treatment with two different inhibitors, Apcin and proTAME, was effective in primary AML cells and in AML cell lines, through induction of apoptosis and mitotic arrest. The lack of correlation between proliferation markers and CDC20 levels in AML cell subpopulations supports the idea of alternative CDC20 functions, independent from its essential role during mitosis. CDC20-KD experiments conducted in AML cell lines revealed a mild effect on apoptosis induction, but no significant change in cell cycle progression. In summary, these results allowed the identification of a new strategy combination to improve the effects of BRD4 inhibition on LSC residing in the BM hypoxic niche, and provide some new evidence regarding the potential role of CDC20 as a new target for AML treatment.

Elementary properties of Modular curves and Modular forms

Lo scopo di questa tesi è introdurre in breve le prime proprietà delle curve modulari e delle forme modulari, per poi mostrarne alcune applicazioni archetipiche. Per farlo, dopo aver richiamato alcune nozioni utili nel primo capitolo, sviluppiamo, nel secondo capitolo, la teoria di base delle curve modulari compatte come superfici di Riemann, calcolandone il genere nel caso dei sottogruppi principali di congruenza. Dunque, nel terzo capitolo, dopo un estesa trattazione dell'esempio delle forme modulari rispetto al gruppo modulare, viene calcolata la dimensione degli spazi delle forme intere e delle forme cuspidali rispetto a un sottogruppo di indice finito del gruppo modulare. Questo capitolo si conclude con tre esempi di applicazione della teoria esposta, tra i quali spiccano la dimostrazione del Grande Teorema di Picard e del Teorema dei quattro quadrati di Jacobi.

δ 15N measurement of organic and inorganic substances by EA-IRMS: a speciation-dependent procedure

Little attention has been paid so far to the influence of the chemical nature of the substance when measuring δ 15N by elemental analysis (EA)-isotope ratio mass spectrometry (IRMS). Although the bulk nitrogen isotope analysis of organic material is not to be questioned, literature from different disciplines using IRMS provides hints that the quantitative conversion of nitrate into nitrogen presents difficulties. We observed abnormal series of δ 15N values of laboratory standards and nitrates. These unexpected results were shown to be related to the tailing of the nitrogen peak of nitrate-containing compounds. A series of experiments were set up to investigate the cause of this phenomenon, using ammonium nitrate (NH4NO3) and potassium nitrate (KNO3) samples, two organic laboratory standards as well as the international secondary reference materials IAEA-N1, IAEA-N2-two ammonium sulphates [(NH4)2SO4]-and IAEA-NO-3, a potassium nitrate. In experiment 1, we used graphite and vanadium pentoxide (V2O5) as additives to observe if they could enhance the decomposition (combustion) of nitrates. In experiment 2, we tested another elemental analyser configuration including an additional section of reduced copper in order to see whether or not the tailing could originate from an incomplete reduction process. Finally, we modified several parameters of the method and observed their influence on the peak shape, δ 15N value and nitrogen content in weight percent of nitrogen of the target substances. We found the best results using mere thermal decomposition in helium, under exclusion of any oxygen. We show that the analytical procedure used for organic samples should not be used for nitrates because of their different chemical nature. We present the best performance given one set of sample introduction parameters for the analysis of nitrates, as well as for the ammonium sulphate IAEA-N1 and IAEA-N2 reference materials. We discuss these results considering the thermochemistry of the substances and the analytical technique itself. The results emphasise the difference in chemical nature of inorganic and organic samples, which necessarily involves distinct thermochemistry when analysed by EA-IRMS. Therefore, they should not be processed using the same analytical procedure. This clearly impacts on the way international secondary reference materials should be used for the calibration of organic laboratory standards.

Relationship between flocculation of activated sludge and composition of extracellular polymeric substances

Activated sludge floes are a flocculated mass of microorganisms, extracellular polymeric substances (EPS) and adsorbed organic and inorganic material. The structure of the floes is very heterogeneous and floes with very different properties and morphologies may occur, depending on the conditions in the activated sludge treatment plant and wastewater composition. Present thinking suggests that cations, such as calcium, create cationic bridges with EPS excreted by the bacteria and thereby hold the various floe constituents together. However, due to the complex and heterogeneous nature of activated sludge, the mechanisms have neither been thoroughly investigated nor successfully quantified. A better understanding and description of the biological flocculation process is necessary in order to establish more efficient operational strategies. The main aim of this study was to get a comprehensive and unique insight into the floe properties of activated sludge and to assess the relative impact of chemical and physical parameters. A variety of sludges from full scale treatment plants with different settling properties were characterised. The interrelationships between floe parameters such as composition of EPS, surface properties and floe structure, and their effect on the flocculation and separation properties were assessed. The results indicate that the EPS, both in terms of quantity and quality, are very important for the floe properties of the activated sludge. However, presence of filaments may alter the physical properties of the floes considerably. The EPS showed positive correlations to sludge volume index (SVI) if only sludges with low or moderate numbers of filaments were included. The surface properties were more affected by the composition of the EPS than by the number of filaments. The EPS showed positive correlation to negative surface charge and a negative correlation to relative hydrophobicity and flocculation ability. The negative correlation between flocculation ability and amount of EPS was surprising. The shear sensitivity, measured as degree of erosion of floes when subjected to shear, was more affected by floe size and number of filaments than amount of EPS.

Mechanical, electrical and electro-mechanical properties of thermoplastic elastomer styrene–butadiene–styrene/multiwal carbon nanotubes composites

Composites of styrene–butadiene–styrene (SBS) block copolymer with multiwall carbon nanotubes were processed by solution casting to investigate the influence of filler content, the different ratios of styrene/butadiene in the copolymer and the architecture of the SBS matrix on the electrical, mechanical and electro-mechanical properties of the composites. It was found that filler content and elastomer matrix architecture influence the percolation threshold and consequently the overall composite electrical conductivity. Themechanical properties aremainly affected by the styrene and filler content. Hopping between nearest fillers is proposed as the main mechanism for the composite conduction. The variation of the electrical resistivity is linear with the deformation. This fact, together with the gauge factor values in the range of 2–18, results in appropriate composites to be used as (large) deformation sensors.

Mechanical, electrical and electro-mechanical properties of thermoplastic elastomer styrene–butadiene–styrene/multiwall carbon nanotubes composites

Composites of styrene–butadiene–styrene (SBS) block copolymer with multiwall carbon nanotubes were processed by solution casting to investigate the influence of filler content, the different ratios of styrene/butadiene in the copolymer and the architecture of the SBS matrix on the electrical, mechanical and electro-mechanical properties of the composites. It was found that filler content and elastomer matrix architecture influence the percolation threshold and consequently the overall composite electrical conductivity. The mechanical properties are mainly affected by the styrene and filler content. Hopping between nearest fillers is proposed as the main mechanism for the composite conduction. The variation of the electrical resistivity is linear with the deformation. This fact, together with the gauge factor values in the range of 2–18, results in appropriate composites to be used as (large) deformation sensors.