Investigating sub-2 μm particle stationary phase supercritical fluid chromatography coupled to mass spectrometry for chemical profiling of chamomile extracts.

Roman and German chamomile are widely used throughout the world. Chamomiles contain a wide variety of active constituents including sesquiterpene lactones. Various extraction techniques were performed on these two types of chamomile.

Automating pressure ulcer risk assessment using documented patient data.

Objective: A rule-based prototype decision support tool; Braden-scale based Automated Risk-assessment Tool (BART) was developed to test whether pressure ulcer risk scores can be determined automatically based on the documented patient data.

Methods: The data items required for assessing pressure ulcer risk were identified by analyzing the parameter definitions of the Braden scale and by consulting the nurses specialized in pressure ulcer prevention and care. Documentation coverage and formats of the required data was evaluated.

Effects of octamethylcyclotetrasiloxane (D4) on the luteinizing hormone (LH) surge and levels of various reproductive hormones in female Sprague-Dawley rats.

The objectives of this study were to assess the potential for D(4) to suppress the pre-ovulatory lutenizing hormone (LH) surge, to block or delay ovulation, and to evaluate potential effects on reproductive hormones in rats. Female Sprague-Dawley Crl:CD (SD) IGS BR rats received whole-body vapor inhalation exposure to D(4) (0, 700, or 900ppm) 6h per day for 3 days. Trunk blood obtained on proestrus at 10a.

Improving LC-MS sensitivity through increases in chromatographic performance: comparisons of UPLC-ES/MS/MS to HPLC-ES/MS/MS.

Recent technological advances have made available reverse phase chromatographic media with a 1.7 microm particle size along with a liquid handling system that can operate such columns at much higher pressures. This technology, termed ultra performance liquid chromatography (UPLC), offers significant theoretical advantages in resolution, speed, and sensitivity for analytical determinations, particularly when coupled with mass spectrometers capable of high-speed acquisitions.

Repeated inhalation exposure to octamethylcyclotetrasiloxane produces hepatomegaly, transient hepatic hyperplasia, and sustained hypertrophy in female Fischer 344 rats in a manner similar to phenobarbital.

Octamethylcyclotetrasiloxane (D4) has been described as a phenobarbital-like inducer of hepatic enzymes. Phenobarbital (PB) and phenobarbital-like chemicals induce transient hepatic and thyroid hyperplasia and sustained hypertrophy in rats and mice. The extent to which these processes are involved with D4-induced hepatomegaly is not known.

Preemptive pain control in patients having laparoscopic hernia repair: a comparison of ketorolac and ibuprofen.

Objectives: To determine if nonsteroidal anti-inflammatory drugs provide adequate pain control for patients having laparoscopic hernia repair and to compare the effectiveness of ketorolac tromethamine with ibuprofen in reducing postoperative laparoscopic hernia pain.

Design And Setting: Prospective double-blind randomized study at a 100-bed community hospital.

Patients: Seventy patients ranging in age from 16 to 83 years scheduled for elective laparoscopic inguinal hernia repair.

Size-selective predation on groundwater bacteria by nanoflagellates in an organic-contaminated aquifer.

Time series incubations were conducted to provide estimates for the size selectivities and rates of protistan grazing that may be occurring in a sandy, contaminated aquifer. The experiments involved four size classes of fluorescently labeled groundwater bacteria (FLB) and 2- to 3-microns-long nanoflagellates, primarily Spumella guttula (Ehrenberg) Kent, that were isolated from contaminated aquifer sediments (Cape Cod, Mass.).

Cyclic food restriction, insulin and mammary cell proliferation in the rat.

We reported recently that weight cycling significantly increased the incidence of mammary cancer in virgin female rats that were pretreated with N-methyl-N-nitrosourea. The present study investigated the effect of weight cycling on mammary epithelial cell proliferation and its relationship to changes in plasma insulin, estrogen, progesterone and urinary corticosterone in 30 female virgin Sprague-Dawley rats. Animals were fed a modified AIN-76A diet containing 24.

Climate Change During the Last Deglaciation in Antarctica.

Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability.

Cyclic food restriction alters substrate utilization and abolishes protection from mammary carcinogenesis female rats.

We tested the hypothesis that cyclic food restriction abolishes protection against mammary carcinogenesis. Virgin female Sprague Dawley rats (n = 159) were injected intraperitoneally with 25 mg/kg n-methyl-n-nitrosourea at 50 d of age. Eleven days later, rats were given free access to a 24.

A human-powered, small radius centrifuge for space application: a design study.

The necessity of preventing physiologic deconditioning of astronauts exposed to long duration space flights is well known. A method under consideration to prevent this deconditioning is the use of periodic exposure to artificial gravity which could be provided by a centrifuge. This paper presents a design study for a human-powered centrifuge which could be used aboard the NASA Space Shuttle with analyses which quantify many of the forces produced.

Increased lipolysis to beta-adrenergic stimulation after dehydroepiandrosterone treatment in rats.

Young adult male rats were treated with 4 mg dehydroepiandrosterone (DHEA)/100-g diet for 4 wk or were fed the same purified diet unadulterated (51 carbohydrate:20 fat: 23.5 protein; wt/wt). After 1 wk body weight and fat mass of the DHEA-fed rats were significantly less than the controls.

Record of Volcanism Since 7000 B.C. from the GISP2 Greenland Ice Core and Implications for the Volcano-Climate System.

Sulfate concentrations from continuous biyearly sampling of the GISP2 Greenland ice core provide a record of potential climate-forcing volcanism since 7000 B.C. Although 85 percent of the events recorded over the last 2000 years were matched to documented volcanic eruptions, only about 30 percent of the events from 1 to 7000 B.

Changes in Atmospheric Circulation and Ocean Ice Cover over the North Atlantic During the Last 41,000 Years.

High-resolution, continuous multivariate chemical records from a central Greenland ice core provide a sensitive measure of climate change and chemical composition of the atmosphere over the last 41,000 years. These chemical series reveal a record of change in the relative size and intensity of the circulation system that transported air masses to Greenland [defined here as the polar circulation index (PCI)] and in the extent of ocean ice cover. Massive iceberg discharge events previously defined from the marine record are correlated with notable expansions of ocean ice cover and increases in PCI.

The atmosphere during the younger dryas.

One of the most dramatic climate change events observed in marine and ice core records is the Younger Dryas, a return to near-glacial conditions that punctuated the last deglaciation. High-resolution, continuous glaciochemical records, newly retrieved from central Greenland, record the chemical composition of the arctic atmosphere at this time. This record shows that both the onset and the termination of the Younger Dryas occurred within 10 to 20 years and that massive, frequent, and short-term (decadal or less) changes in atmospheric composition occurred throughout this event.

Physiologic validation of a short-arm centrifuge for space application.

A short-arm centrifuge (SAC) of 5-6 ft (1.5-1.8 m) radius may be useful in space to measure tolerances to acceleration (G) and to stimulate the cardiovascular system, thereby reducing cardiovascular decompensation that occurs in weightlessness.

Unpredictability of fighter pilot G tolerance using anthropometric and physiologic variables.

Correlation and regression analyses were used to study relationships between centrifuge G tolerances of 1,434 fighter pilots during High-G Training (HGT) and anthropometric and physiologic variables. Multiple regression analyses yielded a four-variable model in which gradual onset run (GOR) relaxed-G tolerance was inversely correlated with height and directly correlated with age, weight, and diastolic blood pressure. Although the four-variable model was able to predict more of the variation in G tolerance than any single variable, neither method showed a correlation (r) of greater than 0.

Centrifuges for studying the effects of sustained acceleration on human physiology.

The operation, development, and use of high-performance centrifuges with high G-onset rates, similar to those found in modern fighter aircraft, are discussed. Their performance characteristics are examined, and the USAFSAM centrifuge at Brooks AFB in Texas is then described. Centrifuges for space research and large-radius track centrifuges are considered.

Effects of diet and exercise on the in vivo rates of the triglyceride-fatty acid cycle in adipose tissue and muscle of the rat.

The effects of feeding a low-protein diet (5 percent w/w) and daily exercise on the rates of substrate (futile) cycling between triglyceride and fatty acids (TG-FA cycle) were studied in rats in vivo using a radiochemical assay that involves following the incorporation of tritium from 3H-H2O into the fatty acid and glycerol moieties of triglyceride. Sixty-four rats were fed either a purified control diet (COND) consisting of 70 percent carbohydrate, 20 percent protein, 5 percent fat or an experimental low protein (LPD) diet consisting of 80 percent carbohydrate, 5 percent protein and 10 percent fat (w/w) and were either exercised six days weekly or remained sedentary for six weeks. Both LPD and exercise training (EXT) were found to increase significantly the rate of TG-FA substrate cycling above the rates observed in dietary and sedentary control groups.

Effect of exercise on the induction of mammary carcinogenesis.

Although data reported in several epidemiological investigations indicate that reduced consumption of dietary fat and increased levels of physical activity are associated with reduced risk for breast cancer, the results of some studies do not support these observations. Underlying this situation is the unanswered question about whether degree of body fatness, which is affected by dietary composition, total caloric intake, and energy expenditure, is the critical determinant affecting breast cancer risk. The objective of this work was to establish whether increasing energy expenditure by exercise would reduce the occurrence of mammary carcinomas induced by 7,12-dimethylbenz[a]anthracene (DMBA) in animals consuming a high fat diet to the level of occurrence observed in sedentary animals consuming a low fat diet.

Modern turtle origins: the oldest known cryptodire.

The discovery of a turtle in the Early Jurassic(185 million years before present) Kayenta Formation of northeastern Arizona provides significant evidence about the origin of modern turtles. This new taxon possesses many of the primitive features expected in the hypothetical common ancestor of pleurodires and cryptodires, the two groups of modern turtles. It is identified as the oldest known cryptodire because of the presence of a distinctive cryptodiran jaw mechanism consisting of a trochlea over the otic chamber that redirects the line of action of the adductor muscle.