Characterization of recast Nafion films by small- and wide-angle X-ray scattering

Room temperature recast Nafion

1 General formula:

films, prepared under different humidities in the curing atmosphere, were characterized by small- and wide-angle X-ray scattering (SAXS and WAXS). SAXS reveals that the humidity influences the size of the ionic clusters in these polymer films. It was found that the number and size of ionic clusters increases with increasing relative humidity. WAXS indicates the presence of locally ordered regions of the backbone polymer. These results allow a qualitative understanding of the electrochemical behaviour of Nafion recast films cured at different humidities, as described in the literature.     

Association of total and central adiposity measures with fasting insulin in a biracial population of young adults with normal glucose tolerance: the CARDIA study.

OBJECTIVE: To determine the association of computed tomography (CT)-measured visceral adipose tissue (AT) and other measures of adiposity with fasting insulin in a biracial (African American and Caucasian) study population of young adults. RESEARCH METHODS AND PROCEDURES: The study population consisted of 251 young adults with normal glucose tolerance (NGT), ages 28-40 years, who were volunteers from the Birmingham, Alabama, and Oakland, California centers of the Coronary Artery Risk Development in Young Adults (CARDIA) study. RESULTS: In regression models with total adiposity measures (body mass index or dual-energy X-ray absorptiometry-measured percent fat), visceral AT (measured as a cross-sectional area in cm2) was generally a stronger predictor of insulin than overall adiposity in all race/gender groups (partial correlation coefficients ranging from 0.31 to 0.47) except for black men, in whom the associations were nonsignificant. Partial correlation coefficients between waist circumference and insulin, controlling for percent fat, were nearly identical to those between visceral AT and insulin in women and in white men. Analyses performed on 2060 NGT CARDIA subjects who were not in this study of visceral AT showed significant correlations of waist circumference with insulin in all race/gender groups, including black men, and that black men in the visceral AT study group were significantly leaner than other black male CARDIA subjects. DISCUSSION: We conclude that visceral AT was associated with fasting insulin in NGT participants in three of the four race/gender groups (black men excepted) and that waist circumference was a good surrogate for visceral AT in examining associations of central adiposity with fasting insulin.     

Coronary artery bypass procedures in septuagenarians are justified. Short and long-term results

BACKGROUND: Elective coronary artery bypass surgery can be performed with low operative mortality. There is a controversial discussion whether short-term and long-term results of CABG justify this procedure in elderly patients. METHODS: To add to this discussion, we evaluated retrospectively, the clinical profile, operative technique, short- and long-term results of 1127 patients over 70 years of age who underwent myocardial revascularization between January 1985 and December 1996. RESULTS: Mean age of the cohort was 73.9 years and it rose continuously. In 1996, septuagenarians represented 21.5% of our coronary patients, in comparison to 6.4% in 1985. Analysis of risk factors showed an increasing prevalence of renal failure, obesity, hyperuricemia and a history of smoking. Preoperatively, 87% of our patients were in NYHA-class III or IV, and thus operated to relieve severe symptoms. The percentage of emergent operations decreased over the observed period by 10.3%. The internal mammary artery was used with rising frequency (44.8% in 1985-1992 vs 61.5% in 1993-1996). The number of simultaneous valve replacements increased, too. Postoperatively, we noted a rising incidence of respiratory failure (17.1%) and neurological disorders (13.7%). On the other hand, the need for intra-aortic balloon pumping and hemofiltration declined by 6.6% and 2.9%, respectively. Perioperative mortality (< or =24 hrs) was 3.65%, hospital mortality (< or =30 days) was 9.64%. The actuarial survival (standard error) at 1 year was 82% (+/-4.3%), and 65.7% (+/-3.8%) at 5 years. CONCLUSIONS: Our data suggest that coronary artery bypass grafting can be performed in septuagenarians at an acceptable risk. Since the large majority of patients improve symptomatically, surgery is a recommendable option for a growing number of elderly patients suffering from severe angina.     

HER2 status in non-small cell lung cancer: results from patient screening for enrollment to a phase II study of herceptin.

PURPOSE: For the first time a large number (563) of non-small cell lung cancer (NSCLC) samples was used to compare three different technologies for the assessment of HER2 status. Fluorescence in situ hybridization (FISH) and immunohistochemistry (IHC) were used for tumor tissue samples, and ELISA for serum samples. The results were compared with other tumor entities, mainly breast. EXPERIMENTAL DESIGN: Samples (563) from patients suffering from primary advanced or metastatic NSCLC were evaluated. RESULTS: HER2 overexpression was demonstrated using IHC in 20% (83 of 410) of the specimens, whereas 2% (7 of 378) were positive by FISH and 6% (31 of 511) showed elevated serum HER2 levels (>15 ng/ml) by ELISA. Sixty-six specimens were positive by IHC only and 13 by ELISA only, whereas none of the specimens was positive only by FISH. Concordance between all of the techniques was seen for only 3 specimens. Of 7 IHC 3+ specimens, 4 showed gene amplification by FISH, and 3 were positive by ELISA (>15 ng/ml), whereas of 76 IHC 2+ cases only 2 were amplified by FISH, and 4 were positive by ELISA. HER2 positivity by at least one of the three techniques was most common in adenocarcinomas, at 29% (42 of 143). CONCLUSION: Gene amplification and HER2 protein overexpression at the 3+ level appear to be uncommon in NSCLC. The concordance between FISH and IHC 3+ disease was good in this study, in addition, ELISA would have detected several patients without IHC/FISH-positive disease.     

Comparison of ciprofloxacin (7 days) and trimethoprim-sulfamethoxazole (14 days) for acute uncomplicated pyelonephritis pyelonephritis in women: a randomized trial

Context  The optimal antimicrobial regimen and treatment duration for acute uncomplicated pyelonephritis are unknown. Objective  To compare the efficacy and safety of a 7-day ciprofloxacin regimen and a 14-day trimethoprim-sulfamethoxazole regimen for the treatment of acute pyelonephritis in women. Design  Randomized, double-blind comparative trial conducted from October 1994 through January 1997. Setting  Twenty-five outpatient centers in the United States. Patients  Of 378 enrolled premenopausal women aged at least 18 years with clinical diagnosis of acute uncomplicated pyelonephritis, 255 were included in the analysis. Other individuals were excluded for no baseline causative organism, inadequate receipt of study drug, loss to follow-up, no appropriate cultures, and other reasons. Interventions  Patients were randomized to oral ciprofloxacin, 500 mg twice per day for 7 days (with or without an initial 400-mg intravenous dose) followed by placebo for 7 days (n = 128 included in analysis) vs trimethoprim-sulfamethoxazole, 160/800 mg twice per day for 14 days (with or without intravenous ceftriaxone, 1 g) (n = 127 included in the analysis). Main Outcome Measure  Continued bacteriologic and clinical cure, such that alternative antimicrobial drugs were not required, among evaluable patients through the 4- to 11-day posttherapy visit, compared by treatment group. Results  At 4 to 11 days posttherapy, bacteriologic cure rates were 99% (112 of 113) for the ciprofloxacin regimen and 89% (90 of 101) for the trimethoprim-sulfamethoxazole regimen (95% confidence interval [CI] for difference, 0.04-0.16; P = .004). Clinical cure rates were 96% (109 of 113) for the ciprofloxacin regimen and 83% (92 of 111) for the trimethoprim-sulfamethoxazole regimen (95% CI, 0.06-0.22; P = .002). Escherichia coli, which caused more than 90% of infections, was more frequently resistant to trimethoprim-sulfamethoxazole (18%) than to ciprofloxacin (0%; P<.001). Among trimethoprim-sulfamethoxazole–treated patients, drug resistance was associated with greater bacteriologic and clinical failure rates (P<.001 for both). Drug-related adverse events occurred in 24% of 191 ciprofloxacin-treated patients and in 33% of 187 trimethoprim-sulfamethoxazole–treated patients, respectively (95% CI, -0.001 to 0.2). Conclusions  In our study of outpatient treatment of acute uncomplicated pyelonephritis in women, a 7-day ciprofloxacin regimen was associated with greater bacteriologic and clinical cure rates than a 14-day trimethoprim-sulfamethoxazole regimen, especially in patients infected with trimethoprim-sulfamethoxazole–resistant strains.      

Surgery for bilateral outflow tract obstruction in elastin arteriopathy

OBJECTIVE: A number of patients with Williams syndrome or other forms of elastin arteriopathy have stenoses of pulmonary arteries in addition to supravalvular aortic stenosis. We sought to investigate the effect of the degree of pulmonary arterial stenosis on the prognosis after an operation for supravalvular aortic stenosis to help define the optimal treatment strategy for patients with severe forms of elastin arteriopathy. METHODS: Between 1960 and 1999, 33 patients underwent operations for supravalvular aortic stenosis while having significant stenoses of the pulmonary arteries. We retrospectively reviewed patient charts, obtained current follow-up information, and determined risk factors for survival and reoperation. RESULTS: Fifteen patients with moderate right-sided obstructions (confirmed by pulmonary artery Z-scores and right ventricular/descending aortic pressure ratio) underwent operations for supravalvular aortic stenosis only. Eighteen patients had more severe right-sided obstructions and underwent surgical relief of pulmonary arterial stenoses or right ventricular outflow tract obstruction in addition to operations for supravalvular aortic stenosis. Eight patients had undergone preoperative balloon dilations of stenotic pulmonary arteries. There were 6 early deaths and 1 late death in our series. Survival at 10 and 20 years was 76% (70% confidence interval, 68%-84%) and freedom from reintervention was 59% (70% confidence interval, 46%-71%) at 10 years and 49% (70% confidence interval, 35%-62%) at 20 years. Multivariate analysis revealed that patients with a right ventricular/descending aortic pressure ratio of 1.0 or more were at higher risk for reintervention but not for death. CONCLUSIONS: Surgical treatment of pulmonary artery obstructions in elastin arteriopathy is palliative but, in conjunction with balloon dilation of peripheral pulmonary arteries, offers good long-term survival to patients with the severest form of elastin arteriopathy.