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Context. The impulsive phase of solar flares is a time of rapid energy deposition and heating in the lower solar atmosphere, leading to changes in the temperature and density structure of the region. Aims. We use an Ov density diagnostic formed from the λ192/λ248 line ratio, provided by the Hinode/EIS instrument, to determine the density of flare footpoint plasma at Ov formation temperatures of ~2.5×105 K, giving a constraint on the properties of the heated transition region. Methods. Hinode/EIS rasters from 2 small flare events in December 2007 were used. Raster images were co-aligned to identify and establish the footpoint pixels, multiple-component Gaussian line fitting of the spectra was carried out to isolate the density diagnostic pair, and the density was calculated for several footpoint areas. The assumptions of equilibrium ionisation and optically-thin radiation for the Ov lines used were assessed and found to be acceptable. For one of the events, properties of the electron distribution were deduced from earlier RHESSI hard X-ray observations. These were used to calculate the plasma heating rate delivered by an electron beam for 2 semi-empirical atmospheres under collisional thick-target assumptions. The radiative loss rate for this plasma was also calculated for comparison with possible energy input mechanisms. Results. Electron number densities of up to 1011.9 cm-3 were measured during the flare impulsive phase using the Ov λ192/λ248 diagnostic ratio. The heating rate delivered by an electron beam was found to exceed the radiative losses at this density, corresponding to a height of 450 km, and when assuming a completely ionised target atmosphere far exceed the losses but at a height of 1450-1600 km. A chromospheric thickness of 70-700 km was found to be required to balance a conductive input to the Ov-emitting region with radiative losses. Conclusions. Electron densities have been observed in footpoint sources at transition region temperatures, comparable to previous results but with improved spatial information. The observed densities can be explained by heating of the chromosphere by collisional electrons, with Ov formed at heights of 450-1600 km above the photosphere, depending on the atmospheric ionisation fraction. [ABSTRACT FROM AUTHOR]

Aims. We present direct evidence of the detection of the main energy release site in a non-eruptive solar flare, SOL2013-11-09T06:38 UT. This GOES class C2.6 event was characterised by two flaring ribbons and a compact, bright coronal source located between them, which is the focus of our study. Methods. We use imaging from SDO/AIA, and imaging spectroscopy from RHESSI to characterise the thermal and non-thermal emission from the coronal source, and EUV spectroscopy from the Hinode/Extreme ultraviolet Imaging Spectrometer, which scanned the coronal source during the impulsive peak, to analyse Doppler shifts in Fe xii (log T = 6.2) and Fe xxiv (log T = 7.2) emission lines, and determine the source density. Results. The coronal source exhibited an impulsive emission lightcurve in all SDO/AIA filters during the impulsive phase. RHESSI hard X-ray images indicate both thermal and non-thermal emission at the coronal source, and its plasma temperature derived from RHESSI imaging spectroscopy shows an impulsive rise, reaching a maximum at 12-13 MK about 10 s prior to the hard X-ray peak. High red-shifts associated with this bright source indicate downflows of 40-250 km s-1 at a broad range of temperatures, interpreted as loop shrinkage and/or outflows along the magnetic field. Outflows from the coronal source towards each ribbon are also observed by SDO/AIA images at 171, 193, 211, 304, and 1600 Å. The electron density of the source obtained from a Fe xiv line pair is 1011.50 cm-3 which is collisionally thick to electrons with energy up to 45-65 keV, responsible for the source's non-thermal X-ray emission. Conclusions. Given the rich observational evidence, we conclude that the bright coronal source is the location of the main release of magnetic energy in this flare, with a geometry consistent with component reconnection between crossing, current-carrying loops. We argue that the energy that can be released via reconnection, based on observational estimates, can plausibly account for the non-thermal energetics of the flare. [ABSTRACT FROM AUTHOR]

The temperature distribution of the emitting plasma is a crucial constraint when studying the heating of solar flare footpoints. However, determining this for impulsive phase footpoints has been difficult in the past due to insufficient spatial resolution to resolve the footpoints from the loop structures, and a lack of spectral and temporal coverage. We use the capabilities of Hinode/Extreme Ultraviolet Imaging Spectrometer to obtain the first emission measure distributions (EMDs) from impulsive phase footpoints in six flares. Observations with good spectral coverage were analyzed using a regularized inversion method to recover the EMDs. We find that the EMDs all share a peak temperature of around 8 MK, with lines formed around this temperature having emission measures (EMs) peaking between 1028 and 1029 cm-5, indicating a substantial presence of plasma at very high temperatures within the footpoints. An EMD gradient of EM(T) ~ T is found in all events. Previous theoretical work on EM gradients shows this to be consistent with a scenario in which the deposited flare energy directly heats only the top layer of the flare chromosphere, while deeper layers are heated by conduction. [ABSTRACT FROM AUTHOR]

This article investigates the perspectives of University of Liverpool graduate foundation doctors and their consultants on their preparedness for professional practice. [ABSTRACT FROM AUTHOR]

The article focuses on the findings of a study related to the practice of consultants as well as their experiences in the health care industry in Great Britain. It explores the experiences of newly appointed consultants and investigates the transition from medical student to doctor. Researchers found that new consultants are highly skilled and experienced professionals but may still need a prescriptive support system.

Background: Fibrosing alveolitis (FA) is the most serious pleuropulmonary extra-articular feature of rheumatoid arthritis (RA). Features that predict progression of FA in patients with RA have not yet been determined.Objective: To identify clinical features that predict progressive FA in patients with RA.Methods: An unselected cohort of 29 patients with RA and FA confirmed by high resolution computed tomography (HRCT) were studied prospectively for 24 months. Three monthly clinical assessment, four monthly pulmonary function tests, and yearly HRCT scanning was undertaken on these patients. Progressive FA was defined as >15% fall in carbon monoxide transfer factor (TLCO) with evidence of increasing FA on HRCT or death as a result of FA.Results: During 24 months of follow up 10/29 (34%) patients had progressive FA. Progression on HRCT was seen as acute ground glass exacerbations or increasing reticular pattern lung involvement. Progressive FA was associated with the presence of bibasal crackles (p=0.041), TLCO (p=0.001), and extent (p=0.026) and distribution (p=0.031) of lung involvement on HRCT at initial presentation. When multiple logistic regression was used, only TLCO remained significant. Receiver operator curve analysis was employed to identify presenting TLCO of progressive FA. A TLCO <54% of the predicted value demonstrated 80% sensitivity and 93% specificity in predicting progressive FA.Conclusions: A TLCO <54% of the predicted value is a highly specific predictor of disease progression. [ABSTRACT FROM AUTHOR]

Background: Fibrosing alveolitis (FA) is a common and serious complication of rheumatoid arthritis (RA). Before the availability of high resolution computed tomographic (HRCT) scanning, it was difficult to diagnose accurately without recourse to biopsy. Prospective studies have reported a prevalence of interstitial lung disease (ILD) of 19-44%. The term ILD used by these authors encompasses a variety of appearances on HRCT scans. This prospective study used HRCT scanning to determine the true prevalence of FA in hospital outpatients with RA, and to study associated clinical characteristics.Methods: One hundred and fifty consecutive patients with RA were selected from a hospital outpatient department, irrespective of the presence or absence of chest disease. All underwent a detailed clinical assessment, chest HRCT scanning, and conventional chest radiography within 4 weeks of full pulmonary function tests.Results: Seventy percent of patients were current or reformed cigarette smokers. Twenty eight (19%) had FA, most frequently of reticular pattern, and 12 of this group (43%) also had emphysematous bullae. None of the previously suggested risk factors for developing FA were confirmed. Fifty four percent of patients with HRCT evidence of FA had bilateral basal chest crackles, 82% had a reduced carbon monoxide transfer factor (TLCO), 14% had restrictive pulmonary function tests, and 14% had bilateral chest radiographic signs of FA.Conclusions: HRCT evidence of FA was present in 19% of hospital outpatients with RA. Abnormalities on chest examination or on full pulmonary function tests, even without restrictive changes or chest radiographic abnormalities, should prompt physicians to request a chest HRCT scan when investigating dyspnoea in patients with RA. [ABSTRACT FROM AUTHOR]

Intravenous administration of quinupristin/dalfopristin outside the hospital setting has not been reported previously. We describe 37 outpatients receiving quinupristin/dalfopristin iv for infections including osteomyelitis, bacteraemia, abscesses and cellulitis. The most frequent aetiological pathogens found were Enterococcus faecium, Staphylococcus aureus and coagulase-negative staphylococci. Patients received an average of 9 days therapy as inpatients and 22 days as outpatients. Quinupristin/dalfopristin was administered using various access devices, most commonly peripherally inserted central catheters and tunnelled central catheters. The bacteriological and clinical success rates were both 89.2%. Five patients were readmitted to hospital; one patient developed catheter-related bacteraemia. The most frequently reported non-venous adverse events were nausea (18.9% of patients), myalgia (18.9%) and arthralgia (13.5%). Sixteen patients experienced venous access-related events, most commonly infusion pain, oedema and phlebitis. In this group of patients, for those who had difficult-to-treat infections, intravenous quinupristin/dalfopristin therapy was generally effective and safe outside the hospital setting. [ABSTRACT FROM AUTHOR]

Context: Knowledge and understanding of gram-negative sepsis have grown over the past 20 years, but the ability to treat severe sepsis successfully has not.Objective: To assess the efficacy and safety of E5 in the treatment of patients with severe gram-negative sepsis.Design: A multicenter, double-blind, randomized, placebo-controlled trial conducted at 136 US medical centers from April 1993 to April 1997, designed with 90% power to detect a 25% relative risk reduction, incorporating 2 planned interim analyses.Setting: Intensive care units at university medical centers, Veterans Affairs medical centers, and community hospitals.Patients: Adults aged 18 years or older, with signs and symptoms consistent with severe sepsis and documented or probable gram-negative infection.Intervention: Patients were assigned to receive 2 doses of either E5, a murine monoclonal antibody directed against endotoxin (n = 550; 2 mg/kg per day by intravenous infusion 24 hours apart) or placebo (n = 552).Main Outcome Measures: The primary end point was mortality at day 14; secondary end points were mortality at day 28, adverse event rates, and 14-day and 28-day mortality in the subgroup without shock at presentation.Results: The trial was stopped after the second interim analysis. A total of 1090 patients received study medication and 915 had gram-negative infection confirmed by culture. There were no statistically significant differences in mortality between the E5 and placebo groups at either day 14 (29.7% vs 31.1%; P = .67) or day 28 (38.5% vs 40.3%; P = .56). Patients presenting without shock had a slightly lower mortality when treated with E5 but the difference was not significant (28.9% vs 33.0% for the E5 and placebo groups, respectively, at day 28; P = .32). There was a similar profile of adverse event rates between E5 and placebo.Conclusions: Despite adequate sample size and high enrollment of patients with confirmed gram-negative sepsis, E5 did not improve short-term survival. Current study rationale and designs should be carefully reviewed before further large-scale studies of patients with sepsis are conducted. [ABSTRACT FROM AUTHOR]

Quinupristin/dalfopristin (Synercid), the first injectable streptogramin antibiotic available for the treatment of complicated gram-positive skin and skin structure infections, was compared with standard comparators (cefazolin, oxacillin or vancomycin) in one USA and one international trial. These two randomized, open-label trials of virtually identical design enrolled a total of 893 patients (450 quinupristin/dalfopristin, 443 comparator). The majority of patients had erysipelas, traumatic wound infection or clean surgical wound infection. Staphylococcus aureus was the most frequently isolated pathogen in both treatment groups and polymicrobial infection was more common in the quinupristin/dalfopristin group than in the comparator group. The clinical success rate (cure plus improvement) in the clinically evaluable population was equivalent between the two treatment groups (68.2% quinupristin/dalfopristin, 70.7% comparator; 95% CI, -10.1, 5.1) despite a shorter mean duration of treatment for quinupristin/dalfopristin patients. In the bacteriologically evaluable population, by-patient and by-pathogen bacteriological eradication rates were somewhat lower for quinupristin/dalfopristin (65.8% and 66.6%, respectively) than for the comparator regimens (72.7% and 77.7%, respectively). The lower bacteriological response rates in the quinupristin/dalfopristin group were, in part, due to a higher rate of polymicrobial infections and a higher incidence of patients classified as clinical failure, a category which included premature discontinuation of treatment because of local venous adverse events. The bacteriological eradication rate for quinupristin/dalfopristin was higher in monomicrobial infections than in polymicrobial infections (72.6% versus 63.3%, respectively), whereas the corresponding rate for the comparator regimens was lower for monomicrobial infections than polymicrobial infections (70.8% versus 83.1%). This finding was not unexpected, since the spectrum of quinupristin/dalfopristin is focused on gram-positive pathogens and additional antibiotics to treat gram-negative bacteria were not required per protocol. The systemic tolerability of both treatment regimens was qualitatively similar. A higher rate of drug-related venous adverse events was reported for quinupristin/dalfopristin (66.2%) than for the comparator regimen (28.4%). Premature discontinuation of study drug was primarily due to adverse clinical events for quinupristin/dalfopristin (19.1%), whereas the most common reason for discontinuation among those receiving the comparator regimens was treatment failure (11.5%). Quinupristin/dalfopristin is an effective alternative for the treatment of hospitalized patients with complicated skin and skin structure infections due to quinupristin/ dalfopristin-susceptible gram-positive organisms, including methicillin- and erythromycin-resistant S. aureus. [ABSTRACT FROM AUTHOR]

An elderly female presented with persistent upper gastrointestinal bleeding from a mucosal lesion in the second part of the duodenum. This failed to respond to surgery, but was successfully treated with aminocaproic acid. [ABSTRACT FROM PUBLISHER]

Five infants born at one hospital over a two-year period developed meningitis due to a serotype 02 strain of Citrobacter diversus; four infants developed brain abscesses due to this organism. The initial prevalence of stool colonization in infants was 79%; eventually 140infants (10%) and six nurses (6%) were found to be colonized. One colonized infant remained in the hospital for the entire two-year period. The strains were of two biotypes marked by the presence (biotype d) or absence (biotype a) of fermentation of sucrose and dulcitol. The biotype d strain was found in the five infants with meningitis, 110 asymptomatic infants, and five nurses. The biotype a strain, which was isolated from 30 infants and one nurse, did not cause disease. Colonized infants were distinguished by intensive care therapy (P = 10-31) , gavage feeding (P = 0.036), and prenatal intrauterine monitoring (P = 0.037).These findings suggest a fecal reservoir and person-to-person transmission of C. diversus. Measures to control the outbreak cost about $110,000. [ABSTRACT FROM PUBLISHER]

Objective: To define the epidemiology and clinical manifestations of hepatitis D virus infection in an institutionalized population.Design: A case-control study of hepatitis B carriers with and without serologic evidence of hepatitis D virus infection. Demographic, institutional, and medical data were obtained through questionnaires and chart review. Clinical status was assessed by liver function assays.Setting: Thirteen Illinois state facilities for the developmentally disabled.Participants: Clients (238) who were hepatitis B carriers.Results: Antibody to hepatitis D virus (anti-HDV) was detected in 71 of 238 (30%) hepatitis B carriers. Nine of thirteen facilities housed positive clients. Previous residence at one facility, designated B, was the strongest correlate of anti-HDV positivity; 85% of positive persons had lived there compared with 16% of negative controls (odds ratio 28.3 [95% CI, 13.2 to 60.7], P less than 0.001). Past hepatitis episodes were more common among anti-HDV-positive clients (37% compared with 7%) (odds ratio, 7.5 [95% CI, 3.0 to 19.1], P less than 0.001) and occurred mainly at facility B from 1950 to 1975. Liver function tests were infrequently abnormal among anti-HDV-positive clients.Conclusions: Results show widespread hepatitis D virus infection in our institutionalized population and suggest that transmission occurred mainly in the past at the overcrowded facility B. The low prevalence of laboratory evidence of chronic liver disease in the anti-HDV-positive clients may be explained by increased mortality among those originally infected from 1950 to 1975. [ABSTRACT FROM AUTHOR]

In a 15-day period, seven patients in a small hospital each had one blood culture positive for Enterobacter cloacae. None of the seven patients was septic. All seven positive culture specimens had been obtained by phlebotomist A, who also had obtained 13 negative culture specimens in the same period. Seven other phlebotomists had drawn 69 blood samples for culture during the same period; none had yielded any microorganism (p = 0.00001). Vials of thrombin, routinely used to coagulate blood specimens for chemical analysis, had been carried on the phlebotomy trays. We observed that phlebotomist A occasionally spilled drops of the viscous thrombin on her finger during the procedures. Culture of the thrombin on her tray yielded E. cloacae. No further cases of E. cloacae bacteremia occurred after she stopped drawing blood for culture and the thrombin on her tray was removed from use. [ABSTRACT FROM AUTHOR]

Presents the response of authors to a letter to the editor about the article "Fibrosing Aiveolitis in Patients With Rheumatoid Arthritis As Assessed by High Resolution Computed Tomography, Chest Radiography, and Pulmonary Function tests," published in the 2001 issue of the journal "Thorax."

Two young women presented with acute bleeding disorders and were subsequently found to have coeliac disease. [ABSTRACT FROM PUBLISHER]