Detecting and correcting hyperlipidemia

The dangers of elevated serum cholesterol levels--and in particular, of increased concentrations of small, dense lipoproteins--have been fully delineated. Although effective therapies are available, too many physicians fail to look for hypercholesterolemia, or fail to treat it effectively. Adhering to therapeutic guidelines and encouraging patient compliance can be lifesaving.     

Prognostic implications of p53 overexpression in cutaneous melanoma from sun-exposed and nonexposed sites

Reduced energy expenditure may predispose children to the development of obesity, but there are limited longitudinal studies to support this theory. We studied 75 white, preadolescent children over 4 y by taking annual measures of body composition and resting energy expenditure (by indirect calorimetry) and two annual measures of total energy expenditure and physical-activity-related energy expenditure (by doubly labeled water). Body composition of parents was assessed at the onset of the study with use of underwater weighing. The major outcome variable was the individual rate of change in fat mass (FM) adjusted for fat-free mass (FFM). The influence of sex, energy expenditure components, initial FM, and parental FM on the rate of change in FM was analyzed by hierarchical linear modeling and analysis of variance. The rate of change in absolute FM was 0.89 +/- 1.08 kg/y (range: -0.44 to 5.6 kg/y). The rate of change in FM adjusted for FFM was 0.08 +/- 0.64 kg/y (range: -1.45 to 2.22 kg/y) and was similar among children of two nonobese parents and children with one nonobese or one obese parent, but was significantly higher in children with two obese parents (0.61 +/- 0.87 kg/y). The major determinants of change in FM adjusted for FFM were sex (greater fat gain in girls), initial fatness, and parental fatness. None of the components of energy expenditure were inversely related to change in FM. The main predictors of change in FM relative to FFM during preadolescent growth are sex, initial fatness, and parental fatness, but not reduced energy expenditure.     

Effect of modulators of protein tyrosine kinase activity on gender-related differences in vascular reactivity at reduced temperature

We used the isolated-muscle-bath technique to examine the effect of protein tyrosine kinase (PTK) and protein tyrosine phosphatase (PTP) inhibitors on the response of rings of tail artery from male and female rats to cooling and reduced temperature in the absence and presence of two PTK-dependent (clonidine and serotonin) and one PTK-independent (phenylephrine, PE) agonists. At 37 degrees C, reactivity to clonidine, serotonin, and PE was the same in tail artery from female and male rats. At 25 degrees C, reactivity to clonidine and serotonin, but not PE, was greater in tail artery from female rats compared with those from male rats. Sodium orthovanadate (SOV) eliminated the gender-related difference in the contractile effect of clonidine and serotonin at 25 degrees C. The sensitivity to relaxation by genistein was considerably greater for clonidine and serotonin at both temperatures as compared with PE. At 25 degrees C the sensitivity to genistein was greater for the clonidine and serotonin-contracted rings from female rats. In the presence of SOV, temperature reduction led to contraction of rat-tail artery. This effect was greater in rings from female rats. Our results strongly implicate differences in the activity of the PTK transduction pathway as the cause of the observed gender-related differences in agonist-mediated contraction at 25 degrees C and in cold-induced vasoconstriction.     

Membrane potential mediates H(+)-ATPase dependence of "degradative pathway" endosomal fusion

BACKGROUND: In recent years Tpot (potential doubling time) has been measured before treatment in human tumors in an attempt to estimate the proliferation taking place during a course of irradiation. Tpot is defined as Ts/LI, where Ts is the duration of DNA synthesis and LI is the labeling index (proportion of cells synthesizing DNA). Ts is more difficult to measure than LI, so the question arises whether variation introduced during the determination of Ts is compensated by the theoretically better relevance of the quotient Tpot than of LI alone. It is not clear from comparisons with clinical outcome whether Tpot is a useful indicator of proliferation or whether LI is more prognostic, as suggested by a currently ongoing multicenter analysis elsewhere. Therefore, we investigated intercomparisons between Tpot and its components LI and Ts in two in their proliferation rates contrasting types of tumor where multiple biopsies were taken from each tumor. MATERIALS AND METHODS: Sixty patients with esophageal carcinoma and 57 patients with breast cancer were included in this study. All patients were injected with IUdR 6-8 h before surgery. From each tumor three to five biopsies were taken at surgery. Using flow cytometry, LI and Ts were measured on all biopsies in order to calculate Tpot. Logarithmic transformations of the distributions were used to examine correlations. Kappa-tests were used to assess how reliable an LI value could be in predicting the corresponding Tpot. RESULTS: Ts and LI were not completely independent, based on the within-tumor coefficients of variation (CVw). The ratio of between-tumor coefficient of variation (CVb) to the CVw suggested that the discriminative power of Tpot was higher than LI for esophagus, but the reverse in breast tumors, which had a larger range. Pearson correlation coefficients were high for log Tpot versus log LI in both types of tumor, but the predictive power was low, as shown by kappa-values of only 0.3-0.41 starting with LI and trying to predict the corresponding value of Tpot. Increasing widths of a central 'gray zone' were investigated for improved discrimination between fast and slow proliferation. Multiples of the within-tumor standard deviation, equally on each side of the median, were used to vary the width of the gray zone. Without a gray zone no more than 70% successful matching was obtained in esophagus tumors, compared with 80% in breast tumors. However, by excluding about half of the esophageal tumors an 80% success rate was achieved. In breast tumors over 90% matching was obtained more easily, keeping 80% of the tumors classifiable. For both tumor types correlations between Ts and Tpot were weak, with a trend towards short Ts associated with short Tpot and also with low LI. The latter correlation was significant for esophageal tumors and resulted in Tpot values having a smaller range than the LIs. CONCLUSION: Although there were good correlation coefficients between Tpot and LI, the predictive power of either from the other was not reliable, except by excluding a significant number of tumors close to the medians. The predictive value of LI for Tpot was higher for breast tumors because the spread in cell kinetic measurements was wide. Until more clinical data become available on outcome in comparison with LI or Tpot, it is still worthwhile to measure Tpot and to assess the prognostic value of both LI and Tpot in relation to outcome.     

Three-dimensional low dose gadolinium-enhanced peripheral MR venography

Cases with absolute immotile sperm syndrome are rare, and include the genetic defect of immotile cilia syndrome with the absence of dynein arms in the flagellum. We attempted to increase the percentage of viable spermatozoa to improve the outcome of intracytoplasmic sperm injection (ICSI). Three couples in whom repeated analysis of the male partners indicated 100% sperm immotility underwent an in-vitro fertilization (IVF) procedure in which ICSI was performed. On their first ICSI cycle the males produced a single ejaculation while in their successive ICSI cycles they were requested to repeatedly ejaculate (two to four times) and only the last ejaculation was used. The eosin-Y test was performed on each used sample. Following their first treatment, one couple had one repeated treatment cycle, another had two and the third couple had three repeated treatment cycles. The mean percentages of viable spermatozoa were 41+/-7.4 and 71+/-6.9% in the first and repeated cycles respectively (P < 0.01; t-test). Of the 39 oocytes injected in the first ICSI cycles only one (3%) was normally fertilized (2PN) compared with 41 (48%) of the 85 oocytes injected in the repeated ICSI cycles. One (3%) embryo in the first and 35 (41%) embryos in the repeated ICSI cycles respectively were obtained (P < 0.001), enabling their replacement into the uterine cavity in all the repeated cycles. One woman (in a repeated cycle) conceived a twin pregnancy and delivered two healthy babies. The use of spermatozoa from repeated ejaculation is recommended in men with absolutely immotile spermatozoa so as to obtain significantly better viability and fertilizing capacity.     

Operation and evaluation of the Willard solar thermal power irrigation system

The operation of the Willard solar thermal power system is analyzed and evaluated. The 19 kW (25 hp) power system was coupled to a shallow well and sprinkler system near Willard, New Mexico irrigating approximately, 49 hectares. The specific performance of the major subsystems—collector array, thermal storage, and the organic working fluid Rankine cycle heat engine—were determined. Over the summer months, the daily collector array efficiency (based on direct solar radiation normalized in the plane of collector aperature) was nominally 25 per cent and heat engine rankine cycle efficiency 15 per cent. These conversion efficiencies coupled with the numerous system losses resulted in an overall efficiency of nearly 3 per cent on clear summer days. Electrical parasitic losses reduced the system's net power output by about 20 per cent on clear days and greater amounts on other days. The maintenance and repair effort was distributed evenly among the collector array and the heat engine.     

Fast lithium-ion conducting thin-film electrolytes integrated directly on flexible substrates for high-power solid-state batteries

By utilizing an equilibrium processing strategy that enables co-firing of oxides and base metals, a means to integrate the lithium-stable fast lithium-ion conductor lanthanum lithium tantalate directly with a thin copper foil current collector appropriate for a solid-state battery is presented. This resulting thin-film electrolyte possesses a room temperature lithium-ion conductivity of 1.5 × 10(-5) S cm(-1) , which has the potential to increase the power of a solid-state battery over current state of the art.