Marked Changes In Concentration Research Articles

Serum Levels of Selected IL-1 Family Cytokines in Patients with Morphea.

Morphea/localized scleroderma (LoS) represents an inflammatory-sclerotic skin disease, the pathogenesis of which is not fully understood. Given the important role of IL-1 family cytokines in the development and therapy of inflammatory diseases, including systemic sclerosis, we analyzed the clinical significance of serum levels of selected IL-1 family cytokines (IL-1α, IL-1β, IL-18, IL-33, IL-37 and IL-38) in LoS patients (n = 30) using the standardized disease assessment tools and comparison to healthy controls (n = 28). We also compared the pre- and post-treatment concentrations, i.e., before and after systemic (glucocorticosteroids and/or methotrexate) and/or topical (topical glucocorticosteroids and/or calcineurin inhibitors). Our findings did not reveal significant differences in baseline IL-1α, IL-1β, IL-18, IL-33, IL-37 and IL-38 levels between LoS group and HCs; however, after treatment, there were marked changes in concentrations of IL-1α and IL-33 within LoS group as well as in comparison to HCs. We also found significant negative correlations between PGA-A and IL-1α concentration as well as between mLoSSI and IL-1α after treatment. Furthermore, we showed an inverse correlation of baseline IL-1β levels with mLoSSI scores of borderline significance. We believe that IL-1α and IL-33, as well as Il-1β, may be potential mediators and targets of interest in LoS.

Abstract 4239: The effects of long-term storage on commonly-measured serum analyte levels

Abstract Introduction: Cohort studies typically bank biospecimens for many years prior to assay and the levels of analyte degradation is unknown. Long storage times could cause degradation and produce measurement errors that would bias estimation of the analyte effects on health outcomes. Such effects could also produce confounding with other factors under study. Methods: We collected control samples from 22 non-study participants using the same enrollment criteria and specimen collection, processing, and storage protocols as in The Sister Study, a large cohort study conducted by the National Institute of Environmental Health Sciences. Samples were assayed for 21 analytes at collection and then six years later. For each sample, the difference between the result at baseline and at six years was calculated for each analyte. The difference, Yij = result6 year - resultbaseline, was then modeled using a mixed-effects model, with random effects for batch (bi) and a fixed effect for the overall mean difference: Yij = u + bi + eij , where , bi ~ N(0, s2batch) , i=1,2,3,5,6. Results: Some of the analytes experienced a marked change in concentration after six years of frozen storage, compared to their baseline value. There were no significant changes in ten of the analytes. Two of the analytes, lactate dehydrogenase (LDH) and sex hormone binding globulin (SHBG), increased significantly in concentration over time. Two analytes, HDL cholesterol and luteinizing hormone (LH), decreased significantly but within the limits of the internal laboratory control variance. Significant reductions in excess of the laboratory control variance were found for 7 of the 21 analytes tested (aspartate transaminase (AST), total cholesterol, estradiol, glucose, protein, sodium, and triglycerides). Despite the evidence for systematic changes over long-term storage, correlations between baseline and later measures were high and there was little relation between the size of the correlation and the estimated mean difference across the two time points. Conclusion: We conclude there are differences in assay results after long-term storage, although for most analytes the correlation coefficients were high and percent change small. Biobanks or cohort studies that bank samples should consider building in QC experiments designed to assess the impact of long-term storage on anticipated analytes of interest, when possible. By doing so, degradation could be corrected for to control bias due to the associated measurement error. Since not all cohorts were able to conduct these QC experiments, those that have carried out such assessment should share their results so others can use the data to evaluate the potential impact of measurement error on their study findings. Citation Format: Cynthia Kleeberger, David Shore, Elaine Gunter, Dale P. Sandler, Sandra Deming-Halverson, Clarice R. Weinberg. The effects of long-term storage on commonly-measured serum analyte levels [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 4239. doi:10.1158/1538-7445.AM2017-4239

Stability of 11-Nor-Δ9-carboxy-tetrahydrocannabinol Glucuronide in Plasma and Urine Assessed by Liquid Chromatography-Tandem Mass Spectrometry

Unconjugated 11-nor-Delta(9)-carboxy-tetrahydrocannabinol (THCCOOH) in blood and urine has been proposed as a valuable marker, but the glucuronide (THCCOOglu) is present in considerably higher concentrations than the parent drug. Acyl glucuronides have been shown to be potentially reactive conjugates, which may affect the in vitro metabolite pattern. Extraction procedures and a liquid chromatography-tandem mass spectrometry assay were developed and validated to investigate the stability of THCCOOglu in urine and plasma. Plasma and urine samples with added THCCOOglu were stored at -20, 4, 20, and 40 degrees C up to 10 days. The glucuronide was stable at -20 degrees C in both matrices, whereas THCCOOglu concentrations decreased at all other storage conditions. For a given storage time and temperature, the decrease in plasma was higher than that in urine. At 20 degrees C, a marked change in concentration could be observed within 2 days of storage. Degradation of THCCOOglu followed an apparent first-order process and led to the formation of THCCOOH. The sum of the molar concentrations of both analytes corresponded only to the initial THCCOOglu in plasma and urine samples stored at 4 degrees C. The in vitro degradation of THCCOOglu prevents clinical conclusions based on the metabolite pattern or the concentration of unconjugated THCCOOH in samples stored at > or =4 degrees C for prolonged periods.

A novel acute phase marker in cattle: lipopolysaccharide binding protein (LBP)

The host response to infection, the "acute phase response" is a highly conserved series of physiological reactions including marked changes in concentrations of plasma proteins. These proteins have been shown to participate in the immune response to infections. Several recent studies have elevated the role of acute phase proteins (APPs) as predictive markers in infection. APPs such as serum amyloid A and haptoglobin but not C-reactive protein (CRP) have been identified as markers of inflammation in cattle. In humans, lipopolysaccharide (LPS) binding protein (LBP) has certain biological functions in host defence and participates in acute phase reactions. We measured plasma levels of LBP in a group of 20 calves experimentally infected with Gram-negative Mannheimia haemolytica (Pasteurella) in comparison to haptoglobin, the most widely studied APP in cattle. In infected calves, LBP levels rose significantly 6 h after infection, reaching a maximum at 24 h. Haptoglobin concentrations significantly rose after 12 h, and peak responses were measured 48 h after infection. Thus, LBP may prove to be a diagnostic marker in cattle infection and is faster than haptoglobin in detecting sepsis.

Late paleozoic atmospheres and biotic evolution

The latter half of the Paleozoic era is marked by notable evolutionary advances, followed by the greatest of all mass extinctions and the subsequent establishment of Mesozoic‐Cenozoic faunas of very different aspect. Current models suggest marked changes in concentration of oxygen and carbon dioxide in the Paleozoic atmosphere. Atmospheric oxygen is thought to have increased from 15% in the mid‐Devonian to near 35% by the end of the Carboniferous, followed by a decline to 17% near the end of the Permian. Atmospheric carbon dioxide was near 0.5% in the early Paleozoic, declining to less than 0.3% in the Devonian, and then more steeply downward to a minimum near 0.04% at the end of the Carboniferous. The principal causes of these changes were the advent and expansion of land plants, deposition of carbonates and continental weathering. Notwithstanding quantitative uncertainties, it seems clear that a major pulse of high oxygen concentration and associated shifts in carbon dioxide characterized the late Paleozoic atmosphere. Atmospheres with such different compositions have markedly different physical characteristics. These changes have major implications for the physiologies of contemporary organisms. The fossil records of various taxa indicate dramatic changes in the biosphere that coincide in time with the inferred changes in composition of the atmosphere. Major changes in phenotype observed in numerous lineages of animals and plants, including accelerated radiations in fresh water and on the land, are inferred to have occurred in response to these changes in the atmosphere. The morphologies, physiologies, and inferred behavior of many organisms preserved in the fossil record are in good accord with expectations based on hyperoxic, low carbon dioxide conditions of the Carboniferous atmosphere and with a return to lower oxygen levels by the end of the Permian.

Intracellular adenosine triphosphate and cyclic adenosine 3',5'-monophosphate concentrations during derepression of actinomycin biosynthesis.

Measurements of adenosine triphosphate and of cyclic adenosine 3′,5′-monophosphate in the mycelium of Streptomyces antibioticus during growth in a medium containing a mixture of glucose and galactose showed no marked changes in concentration during the period when glucose was exhausted and the synthesis of actinomycin began. Thus, these nucleotides do not appear to have a role in mediating catabolite repression of either carbon source utilization or antibiotic production in this organism. Since no NADP-glucohydrolase activity was detected in cell extracts, this enzyme is also excluded from apossible role in regulating actinomycin biosynthesis.

Methane Concentration and Distribution in Pressurized Core Samples from Mississippian Delta Sediments: ABSTRACT

Elevated concentrations of shallow biogenic methane are common in regions of rapid sediment deposition. A pressure core barrel was designed and implemented by Texas A&M University, in conjunction with the U.S. Geological Survey Mississippi Delta Project, to study these gas-charged shallow sediments of the continental shelf. Methane measurements were made on 10 pressurized cores taken in the South Pass region of the Mississippi delta. The results of these measurements indicated methane was present in concentrations ranging from 3,450 to 137,140 ppm (µl CH4(STP)/l wet sediment). Methane values were generally higher than found in comparative samples taken with conventional wire-line equipment. However, these values were lower than predicted by theoretical calculations and also lower than pressure corrected saturation values for methane solubility in seawater. Stepwise decompression experiments were performed on selected samples to study the rate of methane release into the surrounding inert atmosphere of the pressurized sampling container. Results showed that at least 98% of the methane was released from the sediment matrix within 3 to 5 hours after opening the pressurized core. Samples containing higher total methane concentrations demonstrated no change in concentration with pressure during stepwise decompression while those containing lower total methane concentration demonstrated a marked change in concentration with pressure. These experimental results, successfully obtained with pressurized core barrel techniques, provide further in ight into the physical and chemical properties of gas in sediments. End_of_Article - Last_Page 1007------------

The Effect of X-Irradiation on the Metabolism of Folic Acid in Rat Organs

Folic acid (FA) and citrovorum factor (CF) in liver, kidneys, testes, thymus, and spleen of young rats were examined at various periods after x irradiation with 400 or 600 r. in spleen, the amounts of both FA and CF per gram of tissue were significantly diminished a few hours after irradiation, that of CF more than that of FA. These levels remained low for several days. In testes both FA and CF decreased from the tenth day on, the ratio between these two substances remaining unchanged. No marked change in concentration of either.FA or CF occurred in thymus, liver, and kidneys. Local irradiation with3000 r led to a considerable decrease in total amount of both FA and CF on the seventh day after irradiation. Aminopterin in a dose which markedly suppresses formation of CF from FA in the liver was without effect on FA and CF metabolism in spleen and thymus. These results do not support the assumption that the inhibition of formate incorporation and of DNA formation probably resulting from it (known to follow irradiation) is due to an intsnference with the metabolism of FA or the formation of CF. They may reflect changes in the cell population whichmore » take place in certain organs after irradiation. (auth)« less

DISTINCTIVE FEATURES OF THE HEALING OF A CRACK IN A CRYSTAL UNDER CONDITIONS OF DECLINING TEMPERATURE

The concentrations of aqueous solution from which quartz, feldspar, topaz, tourmaline and other minerals crystallize during the hydrothermal stage, is important to an understanding of pegmatite formation. Two opposing theories have been advanced on solution concentration: 1) Pegmatitic minerals separate from highly concentrated solution, without marked change in concentration, by gradual cooling. 2) Pegmatitic minerals separate as a result of flow and of renovation of the exhausted contents of solutions; this need is based on low solubility of silica in pure water. Study of liquid inclusions in minerals reveals that separation of hydrothermal minerals is known to occur from aqueous solutions heavily saturated with alkaline-halide salts, carbonates, borates, and free carbonic acid. From observations made on secondary liquid inclusions in topaz samples from pegmatites, it was found that one-third of the inclusion-cavity volume was occupied by the gas bubble and the remainder of the volume, largely, by small...

NEW DATA ON THE DEPOSITION OF CRYSTAL SUBSTANCE ON CAVITY WALLS OF LIQUID INCLUSIONS

The concentrations of aqueous solution from which quartz, feldspar, topaz, tourmaline and other minerals crystallize during the hydrothermal stage, is important to an understanding of pegmatite formation. Two opposing theories have been advanced on solution concentration: 1) Pegmatitic minerals separate from highly concentrated solution, without marked change in concentration, by gradual cooling. 2) Pegmatitic minerals separate as a result of flow and of renovation of the exhausted contents of solutions; this need is based on low solubility of silica in pure water. Study of liquid inclusions in minerals reveals that separation of hydrothermal minerals is known to occur from aqueous solutions heavily saturated with alkaline-halide salts, carbonates, borates, and free carbonic acid. From observations made on secondary liquid inclusions in topaz samples from pegmatites, it was found that one-third of the inclusion-cavity volume was occupied by the gas bubble and the remainder of the volume, largely, by small...

THE EFFECT OF GROWTH HORMONE UPON LIVER AND KIDNEY D-AMINO ACID OXIDASE AND UPON MUSCLE SUCCINIC ACID DEHYDROGENASE

Since enzymes are proteins, and may indeed constitute a major part of the protein in cells (Sumner and Somers, 1947) several relationships between them and the growth hormone are conceivable. As catalysts, tissue enzymes might be chemical mediators through which certain effects of the hormone are produced; as proteins, they may simply participate in any increase of body protein. In the case of bone phosphatase, marked changes in concentration which are readily correlated with known effects of the growth hormone on skeletal development are observed after hypophysectomy and after replacement therapy, and a functional relationship is indicated (Mathies and Gaebler, 1949). The concentrations of the two enzymes discussed in this paper do not change during induced growth, so there is no indication of a relationship to the growth hormone differing from that of other tissue proteins.