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Recurrence rates following surgical management of chronic subdural haematoma (CSDH) range from 5 to 33 %. There is growing evidence which suggests middle meningeal artery embolisation (MMAe) may reduce recurrence rates when used as surgical adjunct or standalone treatment. In this study we described our experience of this new procedure in the our UK institution. Patients with recurrent CSDH or CSDH at high risk of recurrence were selected for MMAe on a case-by-case basis following MDT discussion. A departmental database was used to identify patients treated. 26 CSDH were embolised in 20 patients; 9 CSDH were de-novo and 17 were recurrent. 10/26 CSDH were treated with MMAe only. No procedural mortality, access site or thrombo-embolic complications occurred. One patient experienced symptomatic collection growth 12 h following MMAe and required surgical drainage. 15 (75 %) of patients were living at home at follow-up (mean 14 months). On imaging follow-up 15/18 showed CSDH volume reduction or resolution, 1/18 remained stable requiring no further treatment, 2/18 patients suffered recurrent CSDH requiring treatment. In both recurrent cases incomplete embolisation was noted on procedural imaging (posterior division of MMA not embolised). Persistent posterior MMA division filling was significantly associated with collection recurrence (p = 0.002). Our results suggest MMAe as a stand-alone or adjuvant therapy can be performed safely in a UK neuroscience setting and is associated with high rates of symptomatic CSDH size reduction or resolution in problematic CSDH that have either recurred or are prone to recurrence.

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Effective management of benthic habitats is important for maintaining heathy and functional aquatic ecosystems. To provide managers with the best possible information, characterizing benthic habitats at the community level is essential; yet, acquiring the data sets needed to achieve this task is resource intensive and, at times, prohibitively expensive. Thus, thoughtful assessments of which data to collect and utilize in benthic habitat characterization studies are needed. Environmental data sets commonly used to characterize benthic habitats include a range of variables from water depth and sediment grain size to seabed features identified by sonar backscatter. The objective of this study was to identify the most useful environmental variables for characterizing infaunal benthic habitats and to determine how to best utilize these variables in analyses (e.g., by comparing continuous vs. categorical explanatory variables). The modeling approach used multivariate regression tree and redundancy analysis along with a critical cross-validation step for model evaluation. Results indicated that models with more than ~7 environmental predictors overfitted the data sets analyzed and that categorizing continuous predictors into categorical ones influenced the proportion of infaunal community variation explained by each model. Habitats identified and characterized on the basis of sonar backscatter explained more of the infaunal community variation than any model that used a combination of other environmental variables (e.g., water depth & sediment grain size) or those constructed using categorical habitat classes from existing classification schemes. We therefore recommend maximizing the potential of sonar-derived variables for characterizing infaunal benthic habitats in nearshore, soft-sediment ecosystems.

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Shrinking lung syndrome (SLS) is a rare manifestation of systemic lupus erythematosus, characterized by progressive dsypnoea, reduced lung volumes and associated restrictive lung physiology. Here, we provide two previously unreported cases, and review the available literature on the pathophysiology, clinical features and management of SLS. Effective treatment can prevent further deterioration or lead to improvement in abnormal lung function. A heightened awareness of SLS and its management is therefore required to prevent disease progression and increased morbidity.

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An apparatus was developed to obtain, for the first time, 2D maps of the surface resistance of the inner surface of an operating superconducting radio-frequency niobium cavity by a low-temperature laser scanning microscopy technique. This allows identifying non-uniformities of the surface resistance with a spatial resolution of about 2.4 mm and surface resistance resolution of ~1 µΩ at 3.3 GHz. A signal-to-noise ratio of about 10 dB was obtained with 240 mW laser power and 1 Hz modulation frequency. The various components of the apparatus, the experimental procedure and results are discussed in detail in this contribution.

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Research on HIV medication adherence has relied mainly on quantitative methods. The objective of this study was to explore factors associated with adherence from the HIV-infected patient's perspective. Six focus groups were convened with treatment-experienced HIV-positive individuals. The discussions focused on issues that make it easy or difficult to adhere to HIV regimens. Thirty-five patients participated in the focus groups, which were conducted in Washington, D.C., and Los Angeles. The mean age was 48; 66% were male; 63% were black; and 40% contracted HIV through heterosexual contact. Six major themes emerged from the data that influenced adherence to medication: regimen complexity/medication features (including number of pills), lifestyle fit, emotional impacts (including worry, anger, stress and anxiety), side effects, medication effectiveness, and communication (including information from friends, physicians, and published sources). The data informed a conceptual framework, illustrating the possible interactions among these themes that can potentially be used by clinicians when discussing HIV treatment options with patients. This is potentially one of the first focus group studies concentrating on HIV medication adherence. The findings highlight specific factors that should be considered when trying to improve adherence and may be helpful in clinical decision-making.

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The objective is to assess patient preferences for attributes associated with third agent HIV medications, including fosamprenavir/ritonavir (FPVr), fosamprenavir (FPV), lopinavir/ritonavir (LPVr), atazanavir (ATZ), and efavirenz (EFV). Subjects with HIV were recruited in the US and Germany to complete a computerized adaptive conjoint survey that assessed 13 attributes, including moderate to severe side effects, regimen convenience, drug resistance and efficacy. Literature on the target third-agent HIV drugs was used to identify percentage risk and severity level descriptions for each attribute. The derived preference (utility) weights for each attribute level informed the calculation of relative importance estimates for each attribute and the desirability of combinations of attributes matching the respective target third agents. The analysis included 288 HIV-positive participants (US: 132; Germany: 156), 205 of whom were treatment-experienced and 83 of whom were treatment-naïve. Of the 13 medication attributes evaluated, developing drug resistance, the risk of lipodystrophy, the risk of gastronitestinal side effects (diarrhoea, nausea and vomiting) and regimen convenience had the greatest impact on preferences. The profile based on FPVr was most preferred. Differences in the risk of developing drug resistance, risk of lipodystrophy, risk of gastrointestinal side effects and regimen convenience would likely be most influential in the perceived relative value of a third-agent medication. Physicians may wish to consider these features, especially when discussing HIV treatment options with their patients.

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The purpose of this retrospective cohort study was to determine the rate and prediction of infection in children, < or = 21 years, with diabetic ketoacidosis (DKA). Over a 6-year period, 247 admissions were identified. There were 171 (69%) with no infection, 44 (17.8%) with presumed viral infection, and 32 (12.9%) with bacterial infection. The mean WBC for all patients was 17,519 ( +/- 9,582). 118 (50%) had leukocytosis as defined by a WBC > or = 15,000/mm3. WBC, differential, leukocytosis, as well as sex, temperature and new onset diabetes, were not significant predictors (P > .05) of bacterial infection. Bacterial infections were more common in children < or = 3 years of age (P = .03). There was a significant correlation of WBC with both pH (r = -0.59, P < .001) and bicarbonate (r = -0.43, P < .001). In conclusion, most children in DKA have no evidence of infection. Leukocytosis is common but most likely reflects the severity of DKA rather than the presence of infection.

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[reaction: see text]. Polyethylene glycol (PEG)-bound poly-L-leucine acts as a THF-soluble catalyst for the Juliá-Colonna asymmetric epoxidation of enones. Excellent enantioselectivities may be obtained even with short chain length polyleucine. FT-IR investigations have determined that the catalytically active polyleucine components of these copolymers have an alpha-helical structure.

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Epoxidation of chalcone (1), using basic hydrogen peroxide, catalysed by polypeptides with defined primary structures demonstrates that the residues in the chain near to the N-terminus determine the stereochemical outcome of the reaction.

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We have analyzed the incidence, management, and outcome of 84 cases of coronary artery perforation in patients who underwent percutaneous coronary intervention at our institution. This complication was more frequent in female patients and in patients who underwent lesion modification with atheroablative devices. A total of 8 patients (9.5%) died after the procedure. They were usually older and had a higher incidence of cardiac tamponade; a larger percentage of these patients underwent emergency surgery than those who survived.

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The hospital records of 22 patients on hemodialysis undergoing coronary artery bypass grafting, and 19 others undergoing percutaneous transluminal coronary angioplasty were reviewed to compare the outcomes of these procedures in this population. Evidence of previous myocardial infarction or triple vessel or left main coronary artery disease was more common in patients undergoing coronary artery bypass graft than those undergoing percutaneous transluminal coronary angioplasty. Perioperative mortality and complication rates following coronary artery bypass graft (4.5% and 41%, respectively) were similar to those following percutaneous transluminal coronary angioplasty (5.3% and 42%). Cardiac event-free rates at 18 months by life-table analysis following coronary artery bypass graft and percutaneous transluminal coronary angioplasty were 87 +/- 16% and 40 +/- 14%, respectively. Survival at 18 months were 67 +/- 17% following coronary artery bypass graft and 69 +/- 14% following percutaneous transluminal coronary angioplasty. Cardiac events were observed to occur in three patients undergoing coronary artery bypass graft at a median of 10 months, and in nine patients following percutaneous transluminal coronary angioplasty at a median of 6 months. One patient required percutaneous transluminal coronary angioplasty after the initial coronary artery bypass graft. Seven patients required repeat percutaneous transluminal coronary angioplasty, and two patients underwent coronary artery bypass graft after initial percutaneous transluminal coronary angioplasty. Although these conclusions are limited by the retrospective nature of the study, it is concluded that coronary artery bypass graft can be performed with morbidity and mortality equivalent to percutaneous transluminal coronary angioplasty, and provides better cardiac event-free rates than percutaneous transluminal coronary angioplasty in patients on hemodialysis. Percutaneous transluminal angioplasty does not appear to be justified in this population because of its unacceptably high restenosis and cardiac event rates.

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We report here the discovery and characterization of a fibrous mineral contaminant of the diet in that area of north-east Iran where oesophageal cancer has a very high incidence. This contaminant has a smoothly tapering shape and is between 50 and 150 micrometers long. The greatest diameter is between 1 and 10 micrometers and this decreases to a sharply pointed tip with a radius of curvature of between 0.25 and 0.60 micrometers. Electron microscope X-ray analysis shows that this fibre consists almost entirely of silica. It is free from alkali metals, aluminium and iron, and therefore differs from other known natural or manmade mineral fibres. Examination of the seeds of more than sixty different species of weed know to contaminate the wheat in this area of the Middle East shows that the fibre originates from the seeds of the common Mediterranean grass Phalaris minor. This seed bears fibres of the same dimensions, composition and birefringence, borne upon the inflorescence bracts which envelop the pericarp of the seeds of this and other members of the phalaris genus. They are broken off from the seed when the wheat is milled but persist in the flour, where up to 3,000 are found in each gram. Similar fibres can be isolated in quantity from the seeds of related species which are grown commercially, and they have a similar size and composition. When cells of the 3T3 mouse fibroblast line are exposed to these fibres in semi-solid suspension culture, their proliferation is stimulated more than 100-fold. We present an hypothesis for the involvement of these plant mineral fibres in the aetiology of oesophageal cancer in Iran and in other areas of high incidence.

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We measured topographical ventilation and perfusion distribution in the gravity field using 133Xe in 5 normal subjects either during natural breathing or during intermittent positive pressure ventilation (IPPB) in the lateral decubitus posture. The ratio of ventilation of upper regions to that of lower regions increased from 0.61 +/- 0.10 (mean +/- SE) during natural breathing to 0.95 +/- 0.08 during IPPB. In contrast, the ratio of regional perfusion was unchanged in the 2 conditions. Consequently, distribution of regional ventilation-perfusion ratios became less homogeneous during IPPB. Whereas during natural breathing the ratio of ventilation-perfusion of upper regions to that of lower regions was 1.09 +/- 0.18, during IPPB this ratio was 1.52 +/- 0.14. Despite the differences in regional ventilation distribution between natural breathing and IPPB, analysis of multiple-breath 133Xe washouts measured at the mouth did not reveal any difference. The results are consistent with the hypothesis that the magnitude of diaphragmatic tension is the main determinant of topographical ventilation distribution in the lateral posture.

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