Galactic and Extragalactic Samples of Supernova Remnants: How They Are Identified and What They Tell Us

Supernova remnants (SNRs) arise from the interaction between the ejecta of a supernova (SN) explosion and the surrounding circumstellar and interstellar medium. Some SNRs, mostly nearby SNRs, can be studied in great detail. However, to understand SNRs as a whole, large samples of SNRs must be assembled and studied. Here, we describe the radio, optical, and X-ray techniques which have been used to identify and characterize almost 300 Galactic SNRs and more than 1200 extragalactic SNRs. We then discuss which types of SNRs are being found and which are not. We examine the degree to which the luminosity functions, surface-brightness distributions and multi-wavelength comparisons of the samples can be interpreted to determine the class properties of SNRs and describe efforts to establish the type of SN explosion associated with a SNR. We conclude that in order to better understand the class properties of SNRs, it is more important to study (and obtain additional data on) the SNRs in galaxies with extant samples at multiple wavelength bands than it is to obtain samples of SNRs in other galaxiesComment: Final 2016 draft of a chapter in "Handbook of Supernovae" edited by Athem W. Alsabti and Paul Murdin. Final version available at https://doi.org/10.1007/978-3-319-20794-0_90-

Assessment of learning curves in complex surgical interventions: a consecutive case-series study

Background: Surgical interventions are complex, which complicates their rigorous assessment through randomised clinical trials. An important component of complexity relates to surgeon experience and the rate at which the required level of skill is achieved, known as the learning curve. There is considerable evidence that operator performance for surgical innovations will change with increasing experience. Such learning effects complicate evaluations; the start of the trial might be delayed, resulting in loss of surgeon equipoise or, if an assessment is undertaken before performance has stabilised, the true impact of the intervention may be distorted. Methods: Formal estimation of learning parameters is necessary to characterise the learning curve, model its evolution and adjust for its presence during assessment. Current methods are either descriptive or model the learning curve through three main features: the initial skill level, the learning rate and the final skill level achieved. We introduce a fourth characterising feature, the duration of the learning period, which provides an estimate of the point at which learning has stabilised. We propose a two-phase model to estimate formally all four learning curve features. Results: We demonstrate that the two-phase model can be used to estimate the end of the learning period by incorporating a parameter for estimating the duration of learning. This is achieved by breaking down the model into a phase describing the learning period and one describing cases after the final skill level is reached, with the break point representing the length of learning. We illustrate the method using cardiac surgery data. Conclusions: This modelling extension is useful as it provides a measure of the potential cost of learning an intervention and enables statisticians to accommodate cases undertaken during the learning phase and assess the intervention after the optimal skill level is reached. The limitations of the method and implications for the optimal timing of a definitive randomised controlled trial are also discussed

Patient safety culture lives in departments and wards: Multilevel partitioning of variance in patient safety culture

<p>Abstract</p> <p>Background</p> <p>Aim of study was to document 1) that patient safety culture scores vary considerably by hospital department and ward, and 2) that much of the variation is across the lowest level organizational units: the wards. Setting of study: 500-bed Norwegian university hospital, September-December 2006.</p> <p>Methods</p> <p>Data collected from 1400 staff by (the Norwegian version of) the generic version of the Safety Attitudes Questionnaire (SAQ Short Form 2006). Multilevel analysis by MLwiN version 1.10.</p> <p>Results</p> <p>Considerable parts of the score variations were at the ward and department levels. More organization level variation was seen at the ward level than at the department level.</p> <p>Conclusions</p> <p>Patient safety culture improvement efforts should not be limited to all-hospital interventions or interventions aimed at entire departments, but include involvement at the ward level, selectively aimed at low-scoring wards. Patient safety culture should be studied as closely to the patient as possible. There may be such a thing as "hospital safety culture" and the variance across hospital departments indicates the existence of department safety cultures. However, neglecting the study of patient safety culture at the ward level will mask important local variations. Safety culture research and improvement should not stop at the lowest formal level of the hospital (wards, out-patient clinics, ERs), but proceed to collect and analyze data on the micro-units within them.</p

Listeria monocytogenes encodes a functional ESX-1 secretion system whose expression is detrimental to in vivo infection

Bacterial pathogenicity deeply depends on the ability to secrete virulence factors that bind specific targets on host cells and manipulate host responses. The Gram-positive bacterium Listeria monocytogenes is a human foodborne pathogen that remains a seriThis work was supported for the DC lab by national funds through FCT - Fundacao para a Ciencia e a Tecnologia/MEC Ministerio da Educacao e Ciencia and co-funded by FEDER funds within the partnership agreement PT2020 related with the research unit number

IDENTIFICATION OF SANDFLIES (Diptera: Psychodidae: Phlebotominae) BLOOD MEALS IN AN ENDEMIC LEISHMANIASIS AREA IN BRAZIL

SUMMARY The aim of this study was to identify blood meals of female sandflies captured in the municipality of Governador Valadares, an endemic area of visceral and cutaneous leishmaniasis, in the State of Minas Gerais, Brazil. From May 2011 to January 2012, captures were performed using HP light traps in four districts. There were 2,614 specimens (2,090 males and 524 females) captured; 97 engorged females were identified belonging to the species Lutzomyia longipalpis (82.1%) and Lutzomyia cortelezzii (17.9%). Considering simple and mixed feeding, the enzyme-linked immunosorbent assay revealed a predominance of chicken blood (43.6%) in Lutzomyia longipalpis, showing the important role that chickens exert around the residential areas of Governador Valadares. This finding increases the chances of sandflies contact with other vertebrates and consequently the risk of leishmaniasis transmission

Mutation detection analysis of a region of 16S-like ribosomal RNA gene of Entamoeba histolytica, Entamoeba dispar and Entamoeba moshkovskii

<p>Abstract</p> <p>Background</p> <p>The level of intra-species genetic variation in <it>Entamoeba histolytica, Entamoeba dispar </it>and <it>Entamoeba moshkovskii </it>populations in a localized geographic area, like Puducherry, India, remains unknown.</p> <p>Methods</p> <p>In the present study the existence of genetic variation in the nested multiplex polymerase chain reaction (NM-PCR) amplified region of the 16S-like ribosomal RNA genes of <it>E. histolytica, E. dispar </it>and <it>E. moshkovskii </it>was investigated by riboprinting and single strand conformation polymorphism (SSCP) analysis.</p> <p>Results</p> <p>We found that 70 stool specimens were positive for <it>E. histolytica</it>, 171 stool specimens were positive for <it>E. dispar</it>, and 37 stool specimens were positive for <it>E. moshkovskii </it>by NM-PCR. Ninety liver abscess pus specimens, 21 urine specimens, and 8 saliva specimens were positive for <it>E. histolytica </it>by NM-PCR. Riboprinting analysis detected a mutation in the PCR product of only one <it>E. histolytica </it>isolate from a stool specimen. However, SSCP analysis detected mutations in the PCR products of five <it>E. histolytica </it>isolates and three <it>E. moshkovskii </it>isolates from stool specimens, and one <it>E. histolytica </it>isolate from a saliva specimen. The mutations detected by riboprinting and SSCP analysis were confirmed by sequencing. All the nucleotide sequences showing mutations in this study have already been deposited into the NCBI GenBank database under accession numbers [GenBank: <ext-link ext-link-type="gen" ext-link-id="EF682200">EF682200</ext-link> to GenBank: <ext-link ext-link-type="gen" ext-link-id="EF682208">EF682208</ext-link>].</p> <p>Conclusion</p> <p>The present study has revealed the subsistence of mutations in the ribosomal RNA genes of <it>E. histolytica </it>and <it>E. moshkovskii</it>, which points towards the existence of intra-species genetic variation in <it>E. histolytica </it>and <it>E. moshkovskii </it>isolates infecting humans.</p

Posterior cavoplasty: a new approach to avoid venous outflow obstruction and symptoms for small-for-size syndrome in right lobe living donor liver transplantation

A common and serious problem after living donor liver transplantation (LDLT) of small grafts is small-for-size syndrome (SFSS). Although hyperdynamic portal inflow and portal hypertension are cornerstones in the development of SFSS, inadequate outflow may aggravate SFSS. Therefore, enlargement of the portal outflow tract by incision of the anterior rim of the orifice of the right hepatic vein (RHV) has been advocated for right lobe LDLT. But backwards tilt of a small graft into a large abdominal cavity may lead to a choking of the otherwise large anastomosis and thus we propose posterior enlargement of the orifice of the RHV. In this test-of-concept study, we evaluated portal vein pressure (PVP), clinical parameters, and laboratory measurements in 22 patients that underwent right lobe LDLT and either received standard end-to-end anastomosis of the RHV or posterior cavoplasty. In patients that underwent posterior cavoplasty, we observed significantly lower PVP and less hyperbilirubinemia. There was a non-significant trend to lower incidence of SFSS. Other laboratory measurements and clinical parameters were not significantly different. We recommend posterior cavoplasty for enlargement of the hepatic venous outflow tract in right lobe LDLT as a method to avoid portal hypertension, hyperbilirubinemia, and possibly SFSS, especially in patients that receive small grafts

Metabolic markers in relation to hypoxia; staining patterns and colocalization of pimonidazole, HIF-1α, CAIX, LDH-5, GLUT-1, MCT1 and MCT4

Contains fulltext : 96097.pdf (postprint version ) (Open Access)BACKGROUND: The cellular response of malignant tumors to hypoxia is diverse. Several important endogenous metabolic markers are upregulated under hypoxic conditions. We examined the staining patterns and co-expression of HIF-1alpha, CAIX, LDH-5, GLUT-1, MCT1 and MCT4 with the exogenous hypoxic cell marker pimonidazole and the association of marker expression with clinicopathological characteristics. METHODS: 20 biopsies of advanced head and neck carcinomas were immunohistochemically stained and analyzed. All patients were given the hypoxia marker pimonidazole intravenously 2 h prior to biopsy taking. The tumor area positive for each marker, the colocalization of the different markers and the distribution of the markers in relation to the blood vessels were assessed by semiautomatic quantitative analysis. RESULTS: MCT1 staining was present in hypoxic (pimonidazole stained) as well as non-hypoxic areas in almost equal amounts. MCT1 expression showed a significant overall correlation (r = 0.75, p < 0.001) and strong spatial relationship with CAIX. LDH-5 showed the strongest correlation with pimonidazole (r = 0.66, p = 0.002). MCT4 and GLUT-1 demonstrated a typical diffusion-limited hypoxic pattern and showed a high degree of colocalization. Both MCT4 and CAIX showed a higher expression in the primary tumor in node positive patients (p = 0.09 both). CONCLUSIONS: Colocalization and staining patterns of metabolic and hypoxia-related proteins provides valuable additional information over single protein analyses and can improve the understanding of their functions and environmental influences

Fatores associados à não adesão aos antirretrovirais em adultos com AIDS nos seis primeiros meses da terapia em Salvador, Bahia, Brasil

O controle da replicação viral é essencial na terapia antirretroviral altamente potente (TARV) e a adesão ao tratamento é o fundamento para esse controle. Fatores individuais e externos influenciam a adesão aos antirretrovirais (ARV). Estudo transversal para investigar fatores associados à não adesão à TARV, em indivíduos com AIDS em Salvador, Bahia, Brasil, com idade ≥ 13 anos e primeira prescrição em 2009. Dados coletados em prontuários e registros da farmácia. Dos 216 pacientes, 65,3% eram homens; idade média 37,8 ± 9,5 anos, solteiros 67,9%; heterossexuais 64%; > 8 anos de estudo 65,3%, etilistas 61,5% e não relatou tabagismo 75,1% ou uso de drogas 93,7%. Iniciaram a TARV com TCD4+ < 350 células/mm3 94%, 61,8% sintomáticos e 68,4% apresentaram reação adversa ao medicamento. Prevalência de não adesão 25%. Variáveis associadas: maior tempo entre o diagnóstico de infecção pelo HIV e a AIDS (aOR = 3,9), reação adversa ao medicamento (aOR = 2,4), idade menor que 34 anos (aOR = 2,2), menos que 8 anos de estudo (aOR = 2,2) e uso de drogas (aOR = 2,6). A alta taxa de não adesão é um problema importante nos seis primeiros meses da TARV