Microbeam x-ray absorption spectroscopy study of chromium in large-grain uranium dioxide fuel.

Synchrotron-based microprobe x-ray absorption spectroscopy (XAS) has been used to study the local atomic structure of chromium in chromia-doped uranium dioxide (UO2) grains. The specimens investigated were a commercial grade chromia-doped UO2 fresh fuel pellet, and materials from a spent fuel pellet of the same batch, irradiated with an average burnup of ~40 MW d kg(-1). Uranium L3-edge and chromium K-edge XAS have been measured, and the structural environments of central uranium and chromium atoms have been elucidated. The Fourier transform of uranium L3-edge extended x-ray absorption fine structure shows two well-defined peaks of U-O and U-U bonds at average distances of 2.36 and 3.83 Å. Their coordination numbers are determined as 8 and 11, respectively. The chromium Fourier transform extended x-ray absorption fine structure of the pristine UO2 matrix shows similar structural features with the corresponding spectrum of the irradiated spent fuel, indicative of analogous chromium environments in the two samples studied. From the chromium XAS experimental data, detectable next neighbor atoms are oxygen and uranium of the cation-substituted UO2 lattice, and two distinct subshells of chromium and oxygen neighbors, possibly because of undissolved chromia particles present in the doped fuels. Curve-fitting analyses using theoretical amplitude and phase-shift functions of the closest Cr-O shell and calculations with ab initio computer code FEFF and atomic clusters generated from the chromium-dissolved UO2 structure have been carried out. There is a prominent reduction in the length of the adjacent Cr-O bond of about 0.3 Å in chromia-doped UO2 compared with the ideal U-O bond length in standard UO2 that would be expected because of the change in effective Coulomb interactions resulting from replacing U(4+) with Cr(3+) and their ionic size differences. The contraction of shortest Cr-U bond is ~0.1 Å relative to the U-U bond length in bulk UO2. The difference in the local chromium environment between fresh and irradiated UO2 is discussed based on the comparison of quantitative structural information obtained from the two chromia-doped fuel samples analyzed.

2-Year course of bipolar disorder type I patients in outpatient care: factors associated with remission and functional recovery.

EMBLEM is a 2-year, prospective, observational study that enrolled patients initiating/changing oral treatment for an acute manic/mixed episode. This paper analysed remission and functional recovery in 1656 patients who entered the 2-year long-term phase. Cox models identified variables significantly associated with achieving remission and functional recovery at 2years. Of these patients, 64% achieved remission and 34% achieved functional recovery. Patients with a higher CGI-BP overall score at baseline, who had depressive episodes in the year before inclusion and who had poor social functioning (work or social impairment, not living independently or without a spouse/partner) were less likely to achieve remission or recovery. Prescription of typical antipsychotics and prescription of antidepressants at the first visit of the long-term treatment phase (12weeks) were independent predictors of lower remission and recovery rates. In conclusion, functional recovery occurred in approximately half of those who achieved remission. Impairment of work and social functioning was consistently associated with lower remission and recovery rates.

Assessment of medication adherence in a cohort of patients with bipolar disorder.

INTRODUCTION: This study aimed to identify factors associated with medication adherence in bipolar disorder (BPD) patients. METHODS: EMBLEM is a 2-year, prospective, observational study on the outcomes of BPD patients initiating or changing treatment for a manic/mixed episode. Data were collected at baseline, during the first 12 weeks of treatment (acute phase) and up to 24 months of follow-up (maintenance phase). Adherence was assessed by investigators at every visit. Repeated measures logistic regression analyses identified variables associated with adherence. RESULTS: Of 1,831 patients included in the analysis, 76.6% were adherent and 23.4% were non-adherent with their BPD medication during the maintenance phase. Patients were more likely to be adherent if they had insight into their illness at week 12. Patients were less likely to be adherent if they had cannabis abuse/dependence during the acute phase, work impairment or higher CGI hallucinations/delusions at baseline DISCUSSION: Psychotic symptoms, poor insight, cannabis abuse/dependence and work impairment are negatively related to medication adherence during maintenance therapy of bipolar disorder. Patients with these characteristics may need a different therapeutic approach.

Translation of randomised controlled trial findings into clinical practice: comparison of olanzapine and valproate in the EMBLEM study.

OBJECTIVES: The aim of this study was to compare the outcomes of olanzapine- and valproate-treated patients in an observational study of acute mania with the results of a randomised controlled trial (RCT) assessing the same treatments. METHODS: EMBLEM (European Mania in Bipolar Evaluation of Medication) was a 2-year, prospective, observational study of health outcomes associated with the treatment of mania. Severity of mania and depression were assessed at baseline and 6 weeks using the YMRS and the 5-item version of the HAMD, respectively. RESULTS: 621 patients were analysed (n=107 valproate, n=514 olanzapine). Both groups improved from baseline to 6 weeks in mean YMRS and HAMD-5 total scores, with greater mean improvements in the olanzapine compared with the valproate group. Olanzapine was associated with more weight gain and less gastrointestinal difficulties than valproate. DISCUSSION: The EMBLEM results support those of the RCT, which suggest that olanzapine monotherapy seems to be more effective than valproate monotherapy in the treatment of acute mania.

Right ureteral injury after radiofrequency ablation for atrial fibrillation.

Percutaneous radiofrequency ablation is a common procedure to treat atrial fibrillation. We describe a patient without a urologic history who had immediate abdominal pain after this treatment. Computed tomography scan and cystoscopy/retrograde pyelography confirmed a right proximal ureteral injury with urinary extravasation. The patient was treated with right ureteral stent placement and urethral catheter drainage. This case appears to be the first report of percutaneous radiofrequency ablation complicated by spontaneous ureteral injury related to blunt injury during manipulation of the transseptal sheaths or intracardiac catheters.

Rapid-cycling bipolar I disorder: course and treatment outcome of a large sample across Europe.

OBJECTIVES: To evaluate the baseline characteristics and follow-up outcomes of rapid-cycling (RC) bipolar I patients in a large, prospective, observational study. METHODS: EMBLEM (European Mania in Bipolar Longitudinal Evaluation of Medication) is a long-term prospective observational study of in- and outpatients with an acute mania/mixed episode conducted in 14 European countries. Demographic and clinical variables were collected at baseline, including the presence or absence of DSM-IV rapid-cycling during the past year. Outcome measures included the 5-item Hamilton Depression Rating Scale (HAMD-5) and Young Mania Rating Scale (YMRS) over 12 weeks, as well as the Clinical Global Impressions-Bipolar Disorder Scale (CGI-BP overall, mania and depression) over 12 months. RESULTS: Of 3684 patients enrolled, 3089 patients provided reliable data to qualify for either RC (N=535, 17.3%) or non-RC (NRC, N=2554), according to DSM-IV. RC prevalence varied across countries (p<0.001). Baseline and 12 week outcomes on the YMRS and HAMD-5, 12 month ratings on the CGI-BP subscales and work impairment at 12 months were significantly different (p<0.001) between groups, being worse in RC. RC patients were more likely to receive antidepressants and lamotrigine (p<0.001). Using logistic regression, RC was associated to country (p<0.001), female sex (p=0.029), outpatients (p=0.035), more history of attempted suicide (p<0.001) and alcohol abuse (p<0.001). CONCLUSIONS: The EMBLEM results suggest that in naturalistic settings, patients with mania and RC differ from NRC in socio-demographic characteristics, treatment prescriptions and clinical outcome measures with a consistently worse occupational outcome and comorbidities. RC represents a longitudinally severe form of bipolar disorder, with poorly evidence-based diagnostic and therapeutic tools.

Patterns of switching phosphodiesterase type 5 inhibitors in the treatment of erectile dysfunction: results from the Erectile Dysfunction Observational Study.

AIMS: This report describes patterns of treatment changes with the phosphodiesterase type 5 (PDE5) inhibitors tadalafil, sildenafil and vardenafil, and variables associated with those treatment changes, during the 6-month, prospective, pan-European Erectile Dysfunction Observational Study (EDOS). METHODS: EDOS observed 8047 men > or = 18 years old with erectile dysfunction (ED), who began or changed ED therapy as part of their routine healthcare. Patients could change ED treatment at any time during EDOS. Data were collected at baseline and at 3 (+/- 1) and 6 (+/- 1) months. Analyses included ED treatment-naïve patients with complete follow-up who were prescribed a PDE5 inhibitor at baseline (n = 4026). RESULTS: Most patients, regardless of what PDE5 inhibitor they were prescribed at baseline, continued on that same PDE5 inhibitor throughout the study. Continuation rates were approximately 89% in the tadalafil cohort, vs. 63-64% in the sildenafil and vardenafil cohorts. The variables most strongly associated with increased risk of switching were prescription of sildenafil or vardenafil, vs. tadalafil, at baseline (odds ratios 4.43 and 4.14 respectively; p < 0.0001). Of patients who switched from tadalafil to another treatment, nearly 25% had switched back to tadalafil by study end. In contrast, of patients who switched from sildenafil or vardenafil, < 10% from each cohort had switched back to their original treatment by study end. CONCLUSION: The data suggest that tadalafil treatment in treatment-naïve ED patients may increase their likelihood of treatment continuation. These findings should be interpreted conservatively due to the observational nature of the study.

Issues in end-of-life care: family practice faculty perceptions.

BACKGROUND: Issues in end-of-life care in the United States are receiving increasing discussion in light of the aging population and the documented need to improve the quality of care for dying patients and their families. Family practice faculty are in a key position to contribute valuable information, given their missions to model necessary values, attitudes, and skills and directly teach quality end-of-life care. METHODS: We conducted interviews with 20 family practice faculty members in 3 residencies, and verbatim transcripts were coded by the authors. We held a second round of 12 interviews in 3 different residencies to check validity and expand the themes emerging from the original interviews. Corrected and elaborated themes were presented to focus groups from 2 other residencies. RESULTS: Themes of reaching consensus; establishing a treatment plan; mobilizing a caregiving system; dealing with relationships with patients, families, and the treatment team; and issues of personal domain were described as important in end-of-life care. CONCLUSIONS: The discussion of quality end-of-life care and how to provide it emphasized traditional medical concerns of diagnosis and prognosis, treatment, and caregiver support. Opportunities for innovation and improvement exist within the less explored areas of the relationship between the provider, patient, and family, and issues of personal meaning and experience.

Green algal cytochrome b6-f complexes: isolation and characterization from Dunaliella saline, Chlamydomonas reinhardtii and Scenedesmus obliquus.

Cytochrome b6-f complexes have been isolated from Chlamydomonas reinhardtii, Dunaliella saline and Scenedesmus obliquus. Each complex is essentially free of chlorophyll and carotenoids and contains cytochrome b6 and cytochrome f hemes in a 2:1 molar ratio. C. reinhardtii and S. obliquus complexes contain the Rieske iron-sulfur protein (present in approx 1:1 molar ratio to cytochrome f) and each catalyzes a DBMIB- and DNP-INT-sensitive electron transfer from duroquinol to spinach plastocyanin. Immunological assays using antibodies to the peptides from the spinach cytochrome complex show varying cross-reactivity patterns except for the complete absence of binding to the Rieske proteins in any of the three complexes, suggesting little structural similarity between the Rieske proteins of algae with those from higher plants. One complex (D. salina) has been uniformly labeled by growth in NaH14CO3 to determine stoichiometries of constituent polypeptide subunits. Results from these studies indicate that all functionally active cytochrome b6-f complexes contain four subunits which occur in equimolar amounts.

Colored silver-intensified gold technique for light microscopy.

The development of silver-intensified immunogold-labeled antibodies for light microscopy described by Fritz et al. (4) has been investigated. Principles and chemistries used in color photographic science have been applied to immunogold enhancement. In this technique, colloidal gold acts as the catalytic center for the reduction of silver ions to metallic silver with subsequent color development in the presence of hydroquinone. Silver ions and hydroquinone are adsorbed onto the surface of colloidal gold. The reduction of silver ions to metallic silver is further catalyzed by autometallography. The colored-SIG technique offers several advantages. It has sensitivity comparable to the silver-intensified gold (SIG) method and greater sensitivity than immunoenzymatic procedures, takes approximately one hour, results in one of three color reaction products (magenta, cyan, or yellow), and produces better contrast between the reaction products and the background (Figure 1). Thus, this method should prove useful in double- and even triple-staining procedures.

Multilayer film analysis: evaluation of ion-selective electrolyte slides.

We evaluated the Kodak Ektachem multilayer ion-selective electrolyte slides. For various types and concentrations of control material the precision (CV) within- and between-day ranged from 0.5 to 1.3% (1.7-2.1%) for sodium, 1.2 to 2.2% (2.7-2.9%) for potassium, 2.9 to 4.6% (5.9-6.7%) for carbon dioxide, and 0.7 to 1.6% (1.3-1.4%) for chloride. For all these analytes, analytical recovery was about 100%, except in the supra-physiological ranges, for which carbon dioxide recovery was about 110-120%. Either serum or heparin-treated plasma can be used, interchangeably, for analysis; use of serum treated with lithium iodoacetate is unacceptable. Comparisons with results by continuous-flow procedures demonstrated good correlation for sodium, potassium, and chloride; carbon dioxide comparisons indicate an Ektachem calibrator change may be required. Abnormally low protein concentrations or lipemia had no observed effects on results for electrolytes. Abnormally high protein concentrations affect sodium results slightly (approximately 5 mmol/L).

A water purification system for laboratory use.

A water purification system is described, capable of producing Type I water upon demand at multiple locations up to 700 feet, from the purifying equipment. Tap water is initially treated employing reverse osmosis, followed by treatment with activated charcoal and mixed anion/cation exchange resins. The resultant Type I quality water is maintained by means of a recycling loop until removal upon demand. The current cost of producing water of this quality is $0.03 per liter, exclusive of capital and installation costs.

Does stereopsis change with age?

Stereopsis thresholds were measured on 242 subjects with normal visual acuity and ranging in age from 8 to 46 years. The results showed no trend with age and no significant sex difference. The log-second threshold mean was 0.74+/-0.21 with a test-retest reliability coefficient of 0.70+/-0.05.