Simple high-performance liquid chromatographic method for determination of losartan and E-3174 metabolite in human plasma, urine and dialysate

A simple high-performance liquid chromatographic (HPLC) method was developed for the determination of losartan and its E-3174 metabolite in human plasma, urine and dialysate. For plasma, a gradient mobile phase consisting of 25 mM potassium phosphate and acetonitrile pH 2.2 was used with a phenyl analytical column and fluorescence detection. For urine and dialysate, an isocratic mobile phase consisting of 25 mM potassium phosphate and acetonitrile (60:40, v/v) pH 2.2 was used. The method demonstrated linearity from 10 to 1000 ng/ml with a detection limit of 1 ng/ml for losartan and E-3174 using 10 microl of prepared plasma, urine or dialysate. The method was utilized in a study evaluating the pharmacokinetic and pharmacodynamic effects of losartan in patients with kidney failure undergoing continuous ambulatory peritoneal dialysis (CAPD).     

Use of concurrent chemotherapy, accelerated fractionation radiation, and surgery for patients with esophageal carcinoma

BACKGROUND: The results of a Phase II study of concurrent chemotherapy and accelerated fractionation radiation therapy followed by surgical resection for patients with both adenocarcinoma and squamous cell carcinoma of the esophagus are presented. Pretreatment and postinduction staging were correlated with pathologic findings at surgery to assess the role of surgical resection and the predictive value of noninvasive staging techniques. METHODS: Patients received 2 induction courses with 4-day continuous intravenous infusions of cisplatin (20 mg/m2/day) and 5-fluorouracil (1000 mg/m2/day) beginning on Day 1 and Day 21, concurrent with a split course of accelerated fractionation radiation (1.5 grays [Gy] twice daily, to a total dose of 45 Gy). All patients were subsequently referred for surgical resection. A single, identical postoperative course of chemotherapy and 24 Gy accelerated fractionation radiation was planned for patients with residual tumor at surgery. RESULTS: Seventy-four patients were entered on this study; 72 patients were considered eligible and evaluable. Induction toxicity included nausea (85%), increased dysphagia (90%), neutropenia (<1000/mm3) (43%), thrombocytopenia (<20,000/mm3) (10%), and reversible nephrotoxicity (8%). Sixty-seven patients (93%) underwent surgery, and 65 (90%) were found to have resectable tumors. Twelve of these patients (18%) died perioperatively, and 18 (27%) had no residual pathologic evidence of disease. Resolution of symptoms and normalization of radiographic studies, endoscopy, or esophageal ultrasound did not identify pathologic complete responders accurately. No patient completing induction therapy and surgery experienced a locoregional recurrence. The Kaplan-Meier 4-year projected recurrence free and overall survival rates were 49% and 44%, respectively. CONCLUSIONS: Although this regimen is feasible, there was significant preoperative toxicity and perioperative mortality. Nonetheless, the recurrence free and overall survival rates were encouraging. However, no staging tool can predict a pathologic complete response after induction therapy accurately, suggesting a continued need for surgical resection.     

Effect of ambient water vapour on stability of lithium niobate electro-optic waveguide devices

A study of the effect of ambient water vapour on the stability of LiNbO3 Mach-Zehnder optical waveguide devices is reported. It is shown using both a conventional stability measurement technique and a novel voltage-stressing technique that the presence of water vapour degrades considerably the stability of these devices.     

Low loss channel waveguides in polymers

The primary routes for creating polymeric channel waveguides are reviewed. Processes, materials, waveguide performance, and applications recently reported in the literature are covered. Emphasis is on an internal diffusion approach under development at Du Pont which has not been widely reported. The intent is to provide a perspective on the flexibility and versatility for fabricating polymer channel waveguides for practical integrated optic applications     

Magnetic properties and microstructures of mischmetal-FeB-(Al, Ti and Al-Co) permanent magnets

The magnetic characteristics of anisotropic MM-FeB- (Al, Ti and Al-Co) permanent magnets have been investigated by using hot-pressing and die-upsetting process. The best magnetic properties obtained in these studies were H _C = 5.1 kOe, B _r = 5.4 kG with (BH)_max = 5.1 MGOe for hot-pressed MM-FeB-Al-Co magnets and H _C = 3.6 kOe, B _r = 6.7 kG, (BH)_max = 6.8 MGOe for die-upset MM-FeB-Al-Co magnets. Higher squareness of demagnetization curve was obtained in anisotropic die-upset MM-FeB- (Al, Al-Co) magnets. X-ray diffraction and STEM investigations revealed that the higher magnetic properties in die-upset magnets were resulted from alignment of the c-axis along the die-upsetting direction. The magnetic anisotropy of the die-upset magnets and the densification of the hot-pressed magnets were increased by partial substitution of Al and Al-Co for Fe.     

Effects of parental separation and divorce on very young children.

Data from the National Institute of Child Health and Human Development Study of Early Child Care were analyzed to explore effects of marital separation on children in the first 3 years of life. The sample included 73 never-married mothers and 97 separated mothers; a comparison group of 170 was conditionally randomly selected from the 2-parent families. Children in 2-parent families performed better than children in 1-parent families on assessments of cognitive and social abilities, problem behavior, attachment security, and behavior with mother. However, controlling for mothers' education and family income reduced these differences, and associations with separated-intact marital status were nonsignificant (the effect size was .01). Thus, children's psychological development was not affected by parental separation per se; it was related to mothers' income, education, ethnicity, childrearing beliefs, depressive symptoms, and behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Can rheometry measure crystallization kinetics? A comparative study using block copolymers

The isothermal crystallization kinetics and the melting behavior of block copolymers of poly(ethylene oxide) and poly(1,2-butylene oxide) were studied by means of differential scanning calorimetry and rheometry to test the validity of rheological methods. The copolymers had different block lengths (hence different melt structures) and different block architectures (diblock EB and triblock EBE and BEB). For crystallization from disordered and lamellar melts, half-times for crystallization from rheometry were much shorter, and Avrami exponents were higher, than those from calorimetry. For more-highly structured melts (gyroid, hexagonal and cubic spheres), the half-times were comparable but the Avrami exponents from rheometry were still high compared to DSC. The differences between the rates of crystallization from calorimetry and rheometry are an artifact of the rheological measurements, at low crystallite volume fractions the rheology is directly proportional to the degree of crystallinity but at high crystalline volume fractions the proportionality is lost due to the changing connectivity of the crystals. The rates of crystallization ranked in order: lamellar>disordered≈gyroid>hexagonal?cubic spheres. Other things being equal, the effect of block architecture was insignificant.     

Unbiased combinations of nonanalog Monte Carlo techniques and fair games

Historically, Monte Carlo variance reduction techniques have developed one at a time in response to calculational needs. This paper provides the theoretical basis for obtaining unbiased Monte Carlo estimates from all possible combinations of variance reduction techniques. Hitherto, the techniques have not been proven to be unbiased in arbitrary combinations. The authors are unaware of any Monte Carlo techniques (in any linear process) that are not treated by the theorem herein.     

A time-course study of the effect of sulphur on glucosinolates in oilseed rape (Brassica napus) from the vegetative stage to maturity

Samples consisting of the whole above-ground part of the oilseed rape plant (Brassica napus L), were taken every 2 weeks from before stem extension to maturity. The plants were separated into vegetative tissue, floral tissue, pods and seeds (when these components appeared), and the individual glucosinolates present were quantified by high performance liquid chromatography. A high glucosinolate variety (Rafal) and a low glucosinolate variety (Cobra) were compared. The effect of sulphur (32 kg ha^?1 elemental sulphur applied at the beginning of stem extension) on the various parts of the plant was investigated. Total glucosinolate concentration in all plant parts was higher in Rafal than in Cobra. Glucosinolate concentration in the vegetation declined over time, most noticeably when the flowers and seeds were produced, and glucosinolate concentration of the pods also fell as that of the seeds rose. It is suggested that there may have been some redistribution of glucosinolates or glucosinolate precursors within the plant as maturity approached. Changes occurred in the proportions that individual glucosinolates contributed to the total glucosinolate content, and this may be relevant to plant/pathogen relationships. Sulphur application increased the glucosinolate concentration of the vegetative tissue by mid April and also increased the glucosinolate concentration of the flowers. It is suggested that this could affect the plant's resistance to disease.     

Modified technique for efficient detection of microsporidia

Changes in temperature (from room temperature to 50 degrees C) and staining time (from 90 to 10 min) were evaluated as a means of improving the detection of microsporidia from stool specimens. A blinded and independent comparison of 50 known positive matched-specimen pairs by three technologists resulted in consistently easier microscopic detection. The background is clearer, and spores stain more intensely. Staining time is reduced by 80 min.