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Obstetric care models in the Southern Region of Brazil and associated factors
The study sought to identify obstetric care models for low-risk pregnancies in the Southern Region of Brazil and to estimate factors associated with these models and maternal and neonatal outcomes. This is a cross-sectional, hospital-based study using data from the Birth in Brazil survey regarding puerperae and newborns. We identified 2,668 low-risk pregnant women. We carried out an exploratory analysis using the proportion of practices per hospital, among them inducing labor, presence of a companion, cesarean section and skin-to-skin contact, in order to obtain the care models we called Best Practice, Interventionist I and Interventionist II. We then carried out an inferential analysis of the associated characteristics. Results show that access to public or private funding, cultural factors and actions taken by health professional are associated with the care models. Public care had different contexts, one based on public policies and evidence-based practices; and another, that suggests the intentionality of vaginal delivery without considering humanization principles. Private care, on the other hand, is standardized and centered on the medical professional, with higher intervention levels. We conclude there is a predominance of interventionist obstetric care models in the Southern Region of Brazil, a type of care that goes against the best evidence, and that women who receive care in public hospitals have greater chances of benefiting from good practices
Study of electron-irradiated silicon thin films using transient photocurrent spectroscopy
Electron irradiation of silicon thin films creates localised states, which degrade theiropto-electronic properties. We present a series of transient photocurrent spectroscopy (TPC)measurements on electron-irradiated amorphous and microcrystalline silicon films, annealed atprogressively increasing temperatures. This has enabled localised states associated with bothdangling bonds and conduction band tails to be examined over a wide energy range.Trends inthe evolution of the DOS following electron irradiation followed by isochronal annealing stepsindicate reductions in the deep defect density,which correlate with spin density. We also find asteepening of the conduction band tail slope in amorphous silicon on annealing. Both defectdensity and tail slope may be restored close to as-prepared material values. Earlier CPM dataare re-examined, and a similar trend in the valence band tail slope is indicated. Computersimulations predict that following e-irradiation changes in deep defect density primarily controlsolar cell performance, and will tend to obscure effects related to band tails
Energy Spectra of Elemental Groups of Cosmic Rays: Update on the KASCADE Unfolding Analysis
The KASCADE experiment measures extensive air showers induced by cosmic rays
in the energy range around the so-called knee. The data of KASCADE have been
used in a composition analysis showing the knee at 3-5 PeV to be caused by a
steepening in the light-element spectra. Since the applied unfolding analysis
depends crucially on simulations of air showers, different high energy hadronic
interaction models (QGSJet and SIBYLL) were used. The results have shown a
strong dependence of the relative abundance of the individual mass groups on
the underlying model. In this update of the analysis we apply the unfolding
method with a different low energy interaction model (FLUKA instead of GHEISHA)
in the simulations. While the resulting individual mass group spectra do not
change significantly, the overall description of the measured data improves by
using the FLUKA model. In addition data in a larger range of zenith angle are
analysed. The new results are completely consistent, i.e. there is no hint to
any severe problem in applying the unfolding analysis method to KASCADE data.Comment: accepted for publication in Astroparticle Physic
Biogenesis and functions of bacterial S-layers.
The outer surface of many archaea and bacteria is coated with a proteinaceous surface layer (known as an S-layer), which is formed by the self-assembly of monomeric proteins into a regularly spaced, two-dimensional array. Bacteria possess dedicated pathways for the secretion and anchoring of the S-layer to the cell wall, and some Gram-positive species have large S-layer-associated gene families. S-layers have important roles in growth and survival, and their many functions include the maintenance of cell integrity, enzyme display and, in pathogens and commensals, interaction with the host and its immune system. In this Review, we discuss our current knowledge of S-layer and related proteins, including their structures, mechanisms of secretion and anchoring and their diverse functions
The Opportunistic Pathogen Propionibacterium acnes: Insights into Typing, Human Disease, Clonal Diversification and CAMP Factor Evolution
We previously described a Multilocus Sequence Typing (MLST) scheme based on eight genes that facilitates population
genetic and evolutionary analysis of P. acnes. While MLST is a portable method for unambiguous typing of bacteria, it is
expensive and labour intensive. Against this background, we now describe a refined version of this scheme based on two
housekeeping (aroE; guaA) and two putative virulence (tly; camp2) genes (MLST4) that correctly predicted the phylogroup
(IA1, IA2, IB, IC, II, III), clonal complex (CC) and sequence type (ST) (novel or described) status for 91% isolates (n = 372) via
cross-referencing of the four gene allelic profiles to the full eight gene versions available in the MLST database (http://
pubmlst.org/pacnes/). Even in the small number of cases where specific STs were not completely resolved, the MLST4
method still correctly determined phylogroup and CC membership. Examination of nucleotide changes within all the MLST
loci provides evidence that point mutations generate new alleles approximately 1.5 times as frequently as recombination;
although the latter still plays an important role in the bacterium’s evolution. The secreted/cell-associated ‘virulence’ factors
tly and camp2 show no clear evidence of episodic or pervasive positive selection and have diversified at a rate similar to
housekeeping loci. The co-evolution of these genes with the core genome might also indicate a role in commensal/normal
existence constraining their diversity and preventing their loss from the P. acnes population. The possibility that members of
the expanded CAMP factor protein family, including camp2, may have been lost from other propionibacteria, but not P.
acnes, would further argue for a possible role in niche/host adaption leading to their retention within the genome. These
evolutionary insights may prove important for discussions surrounding camp2 as an immunotherapy target for acne, and
the effect such treatments may have on commensal lineages
Macroalgal-Associated Dinoflagellates Belonging to the Genus Symbiodinium in Caribbean Reefs
Coral-algal symbiosis has been a subject of great attention during the last two decades in response to global coral reef decline. However, the occurrence and dispersion of free-living dinoflagellates belonging to the genus Symbiodinium are less documented. Here ecological and molecular evidence is presented demonstrating the existence of demersal free-living Symbiodinium populations in Caribbean reefs and the possible role of the stoplight parrotfish (Sparisoma viride) as Symbiodinium spp. dispersers. Communities of free-living Symbiodinium were found within macroalgal beds consisting of Halimeda spp., Lobophora variegata, Amphiroa spp., Caulerpa spp. and Dictyota spp. Viable Symbiodinium spp. cells were isolated and cultured from macroalgal beds and S. viride feces. Further identification of Symbiodinium spp. type was determined by length variation in the Internal Transcribed Spacer 2 (ITS2, nuclear rDNA) and length variation in domain V of the chloroplast large subunit ribosomal DNA (cp23S-rDNA). Determination of free-living Symbiodinium and mechanisms of dispersal is important in understanding the life cycle of Symbiodinium spp
Taskforce report on the diagnosis and clinical management of COVID-19 associated pulmonary aspergillosis
Purpose: Invasive pulmonary aspergillosis (IPA) is increasingly reported in patients with severe coronavirus disease 2019 (COVID-19) admitted to the intensive care unit (ICU). Diagnosis and management of COVID-19 associated pulmonary aspergillosis (CAPA) are challenging and our aim was to develop practical guidance. Methods: A group of 28 international experts reviewed current insights in the epidemiology, diagnosis and management of CAPA and developed recommendations using GRADE methodology. Results: The prevalence of CAPA varied between 0 and 33%, which may be partly due to variable case definitions, but likely represents true variation. Bronchoscopy and bronchoalveolar lavage (BAL) remain the cornerstone of CAPA diagnosis, allowing for diagnosis of invasive Aspergillus tracheobronchitis and collection of the best validated specimen for Aspergillus diagnostics. Most patients diagnosed with CAPA lack traditional host factors, but pre-existing structural lung disease and immunomodulating therapy may predispose to CAPA risk. Computed tomography seems to be of limited value to rule CAPA in or out, and serum biomarkers are negative in 85% of patients. As the mortality of CAPA is around 50%, antifungal therapy is recommended for BAL positive patients, but the decision to treat depends on the patients’ clinical condition and the institutional incidence of CAPA. We recommend against routinely stopping concomitant corticosteroid or IL-6 blocking therapy in CAPA patients. Conclusion: CAPA is a complex disease involving a continuum of respiratory colonization, tissue invasion and angioinvasive disease. Knowledge gaps including true epidemiology, optimal diagnostic work-up, management strategies and role of host-directed therapy require further study
Propionibacterium acnes CAMP Factor and Host Acid Sphingomyelinase Contribute to Bacterial Virulence: Potential Targets for Inflammatory Acne Treatment
) permits the bacteria to spread and become in contact with various skin and immune cells.-induced inflammation. CAMP factor may hijack host ASMase to amplify bacterial virulence to degrade and invade host cells. This work has identified both CAMP factor and ASMase as potential molecular targets for the development of drugs and vaccines against acne vulgaris
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