Ureaplasma parvum causes hyperammonemia in a pharmacologically immunocompromised murine model.

A relationship between hyperammonemia and Ureaplasma infection has been shown in lung transplant recipients. We have demonstrated that Ureaplasma urealyticum causes hyperammonemia in a novel immunocompromised murine model. Herein, we determined whether Ureaplasma parvum can do the same. Male C3H mice were given mycophenolate mofetil, tacrolimus, and prednisone for 7 days, and then challenged with U. parvum intratracheally (IT) and/or intraperitoneally (IP), while continuing immunosuppression over 6 days. Plasma ammonia concentrations were determined and compared using Wilcoxon rank-sum tests. Plasma ammonia concentrations of immunosuppressed mice challenged IT/IP with spent broth (median, 188 µmol/L; range, 102-340 µmol/L) were similar to those of normal (median, 226 µmol/L; range, 154-284 µmol/L, p > 0.05), uninfected immunosuppressed (median, 231 µmol/L; range, 122-340 µmol/L, p > 0.05), and U. parvum IT/IP challenged immunocompetent (median, 226 µmol/L; range, 130-330 µmol/L, p > 0.05) mice. Immunosuppressed mice challenged with U. parvum IT/IP (median 343 µmol/L; range 136-1,000 µmol/L) or IP (median 307 µmol/L; range 132-692 µmol/L) had higher plasma ammonia concentrations than those challenged IT/IP with spent broth (p < 0.001). U. parvum can cause hyperammonemia in pharmacologically immunocompromised mice.

High-sensitivity cardiac troponin T for detection of subtle abnormalities of cardiac phenotype in a general population of elderly individuals.

OBJECTIVE: To investigate the association between circulating cardiac biomarkers and minor abnormalities in cardiac phenotype [left ventricular (LV) mass and midwall fractional shortening (MFS)] in elderly individuals in a general population sample. DESIGN AND SETTING: We examined the relationship between plasma concentrations of high-sensitivity cardiac troponin T (hs-cTnT) or N-terminal probrain natriuretic peptide (NT-proBNP) and elevated LV mass (LV mass/body surface area >95 g m(-2) for women and 115 g m(-2) for men), reduced MFS (<15%) or isolated LV diastolic dysfunction in 1973 elderly subjects (mean age 73 ± 5 years, range 65-84) resident in the Lazio region of Italy and enrolled in the PREDICTOR study. RESULTS: Overall, 24.8% of subjects had elevated LV mass, and 30.4% had reduced MFS. Median [quartile 1-3] plasma concentrations of hs-cTnT and NT-proBNP were higher in individuals with elevated than those with normal LV mass: 6.6 [3.5-11.6] and 147 [64-296] ng L(-1) vs. 4.6 [3.0-8.1] and 79 [41-151] ng L(-1) respectively (P < 0.001). There was a graded increase in median hs-cTnT concentrations across clinical categories of LV hypertrophy: 4.6 [3.0-8.1], 5.8 [3.1-10.2], 7.6 [3.8-13.7] and 8.4 [3.8-17.6] ng L(-1) for subjects with normal LV mass and mild, moderate or severe LV hypertrophy respectively (P < 0.0001); hs-cTnT also increased with increasing quartiles of MFS or grades of isolated LV diastolic dysfunction. CONCLUSIONS: Within an extremely low range of concentrations, increased hs-cTnT amongst community-dwelling elderly subjects is associated with subtle alterations in cardiac phenotype, suggesting that minor injury to cardiac myocytes and subsequent release of troponin reflect subclinical pathophysiological LV deterioration in this population.

An almost head-on collision as the origin of two off-centre rings in the Andromeda galaxy.

The unusual morphology of the Andromeda galaxy (Messier 31, the closest spiral galaxy to the Milky Way) has long been an enigma. Although regarded for decades as showing little evidence of a violent history, M31 has a well-known outer ring of star formation at a radius of ten kiloparsecs whose centre is offset from the galaxy nucleus. In addition, the outer galaxy disk is warped, as seen at both optical and radio wavelengths. The halo contains numerous loops and ripples. Here we report the presence of a second, inner dust ring with projected dimensions of 1.5 x 1 kiloparsecs and offset by about half a kiloparsec from the centre of the galaxy (based upon an analysis of previously-obtained data). The two rings appear to be density waves propagating in the disk. Numerical simulations indicate that both rings result from a companion galaxy plunging through the centre of the disk of M31. The most likely interloper is M32. Head-on collisions between galaxies are rare, but it appears nonetheless that one took place 210 million years ago in our Local Group of galaxies.

Effects of the Temperature and Ethanol on the Kinetics of Proanthocyanidin Adsorption in Model Wine Systems.

The kinetics and quantitative and qualitative effects of grape proanthocyanidin (PA) adsorption to grape skin-derived cell wall material (CWM) were investigated in five different temperature-ethanol conditions. Progress curves for each condition were constructed by monitoring the decrease in concentration of PA solutions after exposure to CWM over 720 min. Adsorption isotherms were constructed for each condition, and a Langmuir equation model was applied to each via regression analysis. Compositional changes in the PA solutions after exposure to CWM were determined using phloroglucinolysis and gel permeation chromatography (GPC). A negative correlation between PA adsorption and both the temperature and ethanol concentration was found. Progress curves suggested that both the temperature and ethanol affect the equilibration rate of the adsorption reactions. Additionally, equilibration rates for lower temperature and ethanol concentration conditions were found to be much longer than previously reported, taking up to 720 min. Phloroglucinolysis results showed no discernible correlation between the temperature or ethanol concentration and percent galloylation or percent gallo units of adsorbed compounds. Analyses by phloroglucinolysis and GPC indicate a preferential adsorption of larger molecular weight PAs under all conditions, although no discernible impact on PA composition was detected. Additionally, findings suggest that both the temperature and ethanol concentration impact the percent reduction in molar mass of the PA solution. Data from this study were ultimately utilized to develop a computational model for predicting phenolic extraction during red wine fermentations.

Probability of metastable configurations in spherical three-dimensional Yukawa crystals.

Recently the occurrence probabilities of ground and metastable states of three-dimensional Yukawa clusters with 27 and 31 particles have been analyzed in dusty plasma experiments [D. Block, Phys. Plasmas 15, 040701 (2008)]. There it was found that, in many cases, the ground state appeared substantially less frequently than excited states. Here we analyze this question theoretically by means of molecular dynamics (MD) and Monte Carlo simulations and an analytical method based on the canonical partition function. We confirm that metastable states can occur with a significantly higher probability than the ground state. The results strongly depend on the screening parameter of the Yukawa interaction and the damping coefficient used in the MD simulations. The analytical method allows one to gain insight into the mechanisms being responsible for the occurrence probabilities of metastable states in strongly correlated finite systems.

Use of heart rate variability analysis to determine the risk of cardiac ischaemia in high-risk patients undergoing general anaesthesia.

The aim of this study was to investigate the use of pre-operative heart rate variability analysis to predict postoperative cardiac events (identified by 24 h Holter-ECG recording and an increase of creatine kinase MB) in high-risk cardiac patients. Length of hospital stay, the incidence of postoperative cardiac ischaemia and cardiac events after discharge were recorded. Fifty patients were assigned by the presence of cardiac events and the heart rate variability in 17 patients with an event was compared with 33 patients without. Total power was identified as a predictive parameter. The usefulness of this test was assessed in a second group of 50 patients. The incidence of cardiac events detected by Holter-ECG recording or an increased creatine kinase MB was greater and the duration of hospital stay longer in the 26 patients with total power < 400 ms(2).Hz(-1) compared with those with total power > 400 ms(2).Hz(-1) (eight and four patients and 10 (7) days (mean (SD)), vs 1 (p < 0.05) and 0 (p < 0.05) patients and 6 (2) days (p < 0.05), respectively). The total power of high-risk cardiac patients predicted postoperative cardiac events and extended length of hospital stay.

Relationship between vaccine vial monitors and cold chain infrastructure in a rural district of India.

INTRODUCTION: The potency of oral polio vaccine (OPV), a heat-labile vaccine, is preserved by the cold chain. The Vaccine Vial Monitor, a heat-sensitive label, is critical to the monitoring and maintenance of the cold chain. This study was conducted to evaluate the relationship between the adequacy of cold chain infrastructure and the proper use of Vaccine Vial Monitor in a rural district of India. METHODS: Forty-six health centers in a rural district were included in our evaluation of the cold chain equipment and the Vaccine Vial Monitors. Cold chain equipment and vaccine vials within each health center were evaluated for adherence to WHO cold chain maintenance protocols and the Vaccine Vial Monitor stage, respectively. RESULTS: Among the 46 health centers, Vaccine Vial Monitor stage I was found at 58% of the health centers, 33% of the health centers reported stage II and 9% reported a stage III, indicating weaknesses in the cold chain mechanism CONCLUSION: Cold chain for the OPV was not adequately maintained at primary and sub-health centers in this rural district. Well maintained ice packs and vaccine carriers will help ensure delivery and availability of a safe and potent vaccine to children in rural areas of India.

Ground state of a confined Yukawa plasma.

The ground state of an externally confined one-component Yukawa plasma is derived analytically. In particular, the radial density profile is computed. The results agree very well with computer simulations of three-dimensional spherical Coulomb crystals. We conclude in presenting an exact equation for the density distribution for a confinement potential of arbitrary geometry.

Spaceflight effects on cultured embryonic chick bone cells.

A model calcifying system of primary osteoblast cell cultures derived from normal embryonic chicken calvaria has been flown aboard the shuttle, Endeavour, during the National Aeronautics and Space Administration (NASA) mission STS-59 (April 9-20, 1994) to characterize unloading and other spaceflight effects on the bone cells. Aliquots of cells (approximately 7 x 10(6)) grown in Dulbecco's modified Eagle's medium (DMEM) + 10% fetal bovine serum (FBS) were mixed with microcarrier beads, inoculated into cartridge culture units of artificial hollow fiber capillaries, and carried on the shuttle. To promote cell differentiation, cartridge media were supplemented with 12.5 microg/ml ascorbate and 10 mM beta-glycerophosphate for varying time periods before and during flight. Four cartridges contained cells from 17-day-old embryos grown for 5 days in the presence of ascorbate prior to launch (defined as flight cells committed to the osteoblastic lineage) and four cartridges supported cells from 14-day-old embryos grown for 10 days with ascorbate before launch (uncommitted flight cells). Eight cartridges prepared in the same manner were maintained under normal gravity throughout the flight (control cells) and four additional identical cartridges under normal gravity were terminated on the day of launch (basal cells). From shuttle launch to landing, all cartridges were contained in closed hardware units maintaining 5% CO2, 37 degrees C, and media delivery at a rate of approximately 1.5 ml/6 h. During day 3 and day 5 of flight, duplicate aliquots of conditioned media and accumulated cell products were collected in both the flight and the control hardware units. At the mission end, comparisons among flight, basal, and control samples were made in cell metabolism, gene expression for type I collagen and osteocalcin, and ultrastructure. Both committed and uncommitted flight cells were metabolically active, as measured by glucose uptake and lactate production, at approximately the same statistical levels as control counterparts. Flight cells elaborated a less extensive extracellular matrix, evidenced by a reduced collagen gene expression and collagen protein appearance compared with controls. Osteocalcin was expressed by all cells, a result indicating progressive differentiation of both flight and control osteoblasts, but its message levels also were reduced in flight cells compared with ground samples. This finding suggested that osteoblasts subjected to flight followed a slower progression toward a differentiated function. The summary of data indicates that spaceflight, including microgravity exposure, demonstrably affects bone cells by down-regulating type I collagen and osteocalcin gene expression and thereby inhibiting expression of the osteogenic phenotype notably by committed osteoblasts. The information is important for insight into the response of bone cells to changes of gravity and of force in general.

Self-reports of health care utilization compared to provider records.

This study compares self-reports of medical utilization with provider records. As part of a chronic disease self-management intervention study, patients completed self-reports of their last six months of health care utilization. A subgroup of patients was selected from the larger study and their self-reports of utilization were compared to computerized utilization records. Consistent with earlier studies, patients tended to report less physician utilization than was recorded in the computerized provider records. However, they also tended to report slightly more emergency room visits than were reported in the computerized utilization records. There was no association between demographic or health variables and the tendency toward discrepancy between self-report and computerized utilization record reports. However, there was a tendency for the discrepancy to increase as the amount of record utilization increased. Thus, the likelihood of bias caused by differing demographic factors is low, but researchers should take into account that underreporting occurs and is likely to increase as utilization increases.

The effects of nicotine chewing gum on the sensitivity to muscle tension.

It has been shown that smoking can alter the sensitivity to muscle activity in female smokers. The present study was designed to assess the effects of smoking cessation and nicotine replacement on sensitivity to muscle tension. Twenty-five women were randomly assigned to one of two groups. One group was given nicotine chewing gum during the withdrawal period and a second group was given no nicotine replacement. Results showed a significant difference in sensitivity at post-test for subjects given nicotine gum compared to subjects receiving no nicotine replacement. These results are consistent with the hypothesis that nicotine alters sensitivity to muscle tension.

Placental 17 beta-hydroxysteroid oxidoreductase, lactate dehydrogenase and malate dehydrogenase during the latter half of pregnancy in the mouse.

The specific activity of 17 beta-hydroxysteroid oxidoreductase (17-HOR) with estradiol-17 beta (E2), estrone (E1) and testosterone (T), as well as that of lactate dehydrogenase (LDH) and malate dehydrogenase (MDH) were measured in homogenates of CF-1 mouse placenta during the latter half of pregnancy. 17-HOR activity with E2 and T increased over 100-fold between days 9 and 12, and 3- to 4-fold between days 15 and 19, with no further change to day 21. In contrast, activity with E1 increased 39-fold between days 9 and 12, 3.8-fold between days 15 and 19 but then decreased between days 19 and 21. The E2/T activity ratio was constant while the E2/E1 ratio increased between days 9 and 21. LDH increased 2-fold between days 9 and 12 with no further increase to day 19. MDH was constant from day 9 to 19. Activity with E2 was inhibited by T, 5 alpha-dihydrotestosterone (5 alpha-DHT) and DHA but not by E1, androstenedione (A) or 20 alpha-dihydroprogesterone. Activity with T was inhibited by E2, 5 alpha-DHT and DHA, but not by A. In contrast, activity with E1 was inhibited by A and DHA but not by E2, T or 5 alpha-DHT. The results suggest placental 17-HOR is developmentally regulated. Although the results are also suggestive of multiple forms of 17-HOR, a single enzyme with an ordered kinetic mechanism cannot be ruled out.

Fasted state impedes recovery of porcine hepatic oxygen consumption after warm hepatic ischemia.

The most effective means to prepare the hepatic donor liver for harvest, preservation, and transplantation are not known. Studies have shown that in combination with an injury to the liver, fasting reduces hepatic function. This study randomized 20 market pigs, 20 to 45 kg, to an overnight fast (fed group) or a 42-hour fast (fasted group). Under general anesthetic perfusion of the portal vein and hepatic artery were controlled. Studies were performed at high flow (30 ml/min/kg portal flow and 10 ml/min/kg arterial flow) and after a 90-minute period of warm ischemia (no flow). Flow was restored at 25% of the original (low flow), then increased to 50% of the original (medium flow). After the ischemic insult, the fed group improved hepatic oxygen consumption at a faster rate than the fasted group (p less than 0.05 by ANOVA). In addition, significant differences were noted between the fed and fasted groups in the amount of insulin delivered by the portal venous system to the liver (p less than 0.001 by ANOVA). Hepatic oxygen consumption was related to insulin delivery (r2 = 0.46; p less than 0.001) for both groups. The data suggest that acute changes in the nutritional status of both the donor and the recipient may affect hepatic recovery from ischemia.

Slit scanning of Saccharomyces cerevisiae cells: quantification of asymmetric cell division and cell cycle progression in asynchronous culture.

Slit scanning flow cytometry has been applied to the analysis of the cell cycle and cell-cycle-dependent events in Saccharomyces cerevisiae, yielding information on the low-resolution spatial distribution of cellular components in single cells of unperturbed cell populations. Because this process is rapid, large numbers of cells can be analyzed to give distributions of parameters in a given population. To study asymmetric cell division and cell cycle progression, forward-angle light scattering (FALS) signals together with fluorescence signals from acriflavine-stained nuclei have been measured in cells from exponentially growing yeast populations. An algorithm has been developed that assigns the position of the bud neck in the FALS signals so that both FALS and DNA signals can be analyzed in terms of the contributions from the mother cell and the cell bud. The data indicate that mother cell FALS, on average, remains constant while FALS due to the cell bud increases as a cell progresses through the cell cycle. By identifying mitotic cells and measuring their properties, we have found that the coefficient of variation for the distribution of FALS is smallest within the dividing cell population and largest within the newborn cell population, in accordance with the critical size control mechanism of yeast cell growth. The use of this experimental approach to provide data for statistical population models is discussed.

Synchronization of drift waves.

Based on a thorough experimental study of the equilibrium plasma state and the description of coherent drift modes in the framework of a linear, nonlocal model, the response of drift modes to different external driver signal is reported. Purely temporal perturbations as well as corotating and counter-rotating electric fields of various mode numbers are applied to the system. Drift mode synchronization and periodic pulling, typical for driven nonlinear oscillator systems, are investigated in detail. The full spatio-temporal behavior of periodic pulling is observed with multiprobe arrays.

The effects of physical activity as maintenance for smoking cessation.

The effects of physical activity as a maintenance strategy for smoking cessation were evaluated. After a standard smoking cessation program, forty-two women were randomly assigned to one of three groups that received equal number of maintenance meetings: a physical activity program, smoking habit change information and contact control. Abstinence decreased from 83% at the end of treatment to 73% at 3 months, 49% at six months and 34% at 18 months. No differences were shown in cessation across groups. Group differences were shown for subjective levels of tension-anxiety, those who exercised showed increased tension anxiety levels compared to subjects in the no activity groups.

Placental teratoma.

The rare teratoma of the placenta has been compared to the fetus amorphus, two distinguishing characteristics being the teratoma's lack of structural organization and lack of large vessels entering the tumor. A case of placental teratoma and theories of origin are discussed.

A controlled study of silver nitrate prophylaxis and the incidence of nasolacrimal duct obstruction.

The caustic property of silver nitrate prompted a double-blind, controlled study of a possible causal relationship between use of the agent for prophylaxis against ophthalmic infection in the newborn and the subsequent development of nasolacrimal duct obstruction. Follow-up of 145 newborns randomized either to 1% silver nitrate prophylaxis or to 1% tetracycline prophylaxis revealed no statistically significant difference in the incidence of nasolacrimal duct obstruction between the two groups at either two weeks or two months of age. It is concluded that silver nitrate prophylaxis does not predispose to nasolacrimal duct obstruction in the newborn.

New concepts in systemic autoimmunity testing.

Diagnosis of systemic autoimmune diseases is highly complex, and it is becoming increasingly difficult to make assumptions about the functional roles and diagnostic significance of autoantibodies. The latter is mainly due to the fact that results from different assay systems are not interchangeable. A laboratory "gold standard" which helps the clinician to differentiate irrelevant autoimmune phenomena from significant autoimmune diseases at an early stage, is clearly missed. To meet this challenge, a rheuma entrance screening (RES) assay toolbox is proposed based on fully-automated enzyme immunoassay (EIA) technology on one system for the clinical and routine laboratory. The RES concept is intended to cover the most important syndromes of systemic rheumatic diseases, i.e. collagenosis, early rheumatoid arthritis, early osteoarthritis, anti-phospholipid syndrome and inflammation. The serological part of diagnosis of these diseases comprises testing for anti-nuclear antibodies (ANA), rheumatoid factor (RF), low levels of C-reactive protein (CRP), and disease-specific anti-phospholipid antibodies, e.g. anti-beta-2 glycoprotein I (anti-beta2 GPI). To eliminate the known problems of varying assay systems in this field, a novel, objective, rapid and reproducible approach to screen for such analytes in patient serum or plasma more efficiently is the application of EIAs on the fully-automated immunoassay analyser COBAS CORE (Roche Diagnostics GmbH, Mannheim, Germany). The combined use of the RES (COBAS CORE HEp2 ANA EIA, COBAS CORE RF EIA Quant, COBAS CORE CRP EIA Quant and COBAS CORE Anti-beta2 GPI EIA) is intended for patients sent to the laboratory with the primary suspicion of harbouring a systemic rheumatic disease.