197 research outputs found
GLUCOCORTICOID-INDUCED ALTERATION OF THE SURFACE MEMBRANE OF CULTURED HEPATOMA CELLS
Glucocorticoids induce an alteration of the surface of hepatoma tissue culture (HTC) cells as expressed by changes in cell electrophoretic, antigenic, and adhesive properties. The alteration is assayed by the increased adhesiveness of induced cells for a glass surface. The induction process has a lag period of about 3 hr and attains a plateau level after 24–30 hr when 50–80% of the steroid-treated cells are firmly adhered. Less than 10% of untreated cells adhere under the same conditions. Induction is inhibited by actinomycin D and cycloheximide, demonstrates both pH and temperature dependence, and responds to changes in steroid concentration and structure. By contrast, the attachment per se of preinduced cells is not affected by inhibitors of RNA and protein synthesis, fluctuations of temperature and pH, and the presence or absence of the hormone. When the induction process is reversed by removal of steroid or addition of actinomycin D, preinduced adhesiveness is lost with a half-life of 13–24 hr, but in the presence of cycloheximide the loss is accelerated (t1/2 3–5.5 hr). These results suggest that glucocorticoids induce the biosynthesis of a protein which either modifies the cell surface (an enzyme) or is incorporated into surface structures (structural protein)
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Genetic variation in CRHR1 is associated with short-term respiratory response to corticosteroids in preterm infants at risk for bronchopulmonary dysplasia.
BackgroundBronchopulmonary dysplasia (BPD) is an orphan disease and advances in prevention and treatment are lacking. The clinical efficacy of systemic corticosteroid therapy to reduce the severity of lung disease and BPD is highly variable. Our objective was to assess whether candidate SNPs in corticosteroid metabolism and response genes are associated with short-term phenotypic response to systemic corticosteroids in infants at high risk for BPD.MethodsPharmacogenetic analysis of data from a large randomized controlled trial (TOLSURF) in infants treated with dexamethasone or hydrocortisone using multivariate linear regression. The primary outcome was a change in respiratory severity score (RSS, mean airway pressure x FiO2) at day 7 of corticosteroid treatment.Resultsrs7225082 in the intron of CRHR1 is significantly associated with the magnitude of decrease in RSS 7 days after starting treatment with systemic corticosteroid (meta-analysis P = 2.8 × 10-4). Each T allele at rs7225082 is associated with a smaller absolute change in RSS at day 7, i.e., less response to systemic corticosteroids.ConclusionsGenetic variability is associated with corticosteroid responsiveness with regard to respiratory status in preterm infants. Identification of genetic markers of corticosteroid responsiveness may allow for therapeutic individualization, with the goal of optimizing the risk-to-benefit ratio for an individual child
ACCURACY AND PRECISION OF ESTIMATING AGE OF GRAY WOLVES BY TOOTH WEAR
We evaluated the accuracy and precision of tooth wear for aging gray wolves (Canis lupus) from Alaska, Minnesota, and Ontario based on 47 known-age or known-minimum-age skuIIs. Estimates of age using tooth wear and a commercial cementum annuli-aging service were useful for wolves up to 14 years old. The precision of estimates from cementum annuli was greater than estimates from tooth wear, but tooth wear estimates are more applicable in the field. We tended to overestimate age by 1-2 years and occasionaIIy by 3 or 4 years. The commercial service aged young wolves with cementum annuli to within ± 1 year of actual age, but under estimated ages of wolves 2:9 years old by 1-3 years. No differences were detected in tooth wear patterns for wild wolves from Alaska, Minnesota, and Ontario, nor between captive and wild wolves. Tooth wear was not appropriate for aging wolves with an underbite that prevented normal wear or severely broken and missing teeth
Surfactant status and respiratory outcome in premature infants receiving late surfactant treatment.
BACKGROUND:Many premature infants with respiratory failure are deficient in surfactant, but the relationship to occurrence of bronchopulmonary dysplasia (BPD) is uncertain. METHODS:Tracheal aspirates were collected from 209 treated and control infants enrolled at 7-14 days in the Trial of Late Surfactant. The content of phospholipid, surfactant protein B, and total protein were determined in large aggregate (active) surfactant. RESULTS:At 24 h, surfactant treatment transiently increased surfactant protein B content (70%, p < 0.01), but did not affect recovered airway surfactant or total protein/phospholipid. The level of recovered surfactant during dosing was directly associated with content of surfactant protein B (r = 0.50, p < 0.00001) and inversely related to total protein (r = 0.39, p < 0.0001). For all infants, occurrence of BPD was associated with lower levels of recovered large aggregate surfactant, higher protein content, and lower SP-B levels. Tracheal aspirates with lower amounts of recovered surfactant had an increased proportion of small vesicle (inactive) surfactant. CONCLUSIONS:We conclude that many intubated premature infants are deficient in active surfactant, in part due to increased intra-alveolar metabolism, low SP-B content, and protein inhibition, and that the severity of this deficit is predictive of BPD. Late surfactant treatment at the frequency used did not provide a sustained increase in airway surfactant
Messina (\u3cem\u3eMelilotus siculus\u3c/em\u3e)–A New Pasture Legume for Saltland
Messina (Melilotus siculus ((Turra) Vitman ex B.D. Jacks)) is a new annual pasture legume for saltland in temperate Australia and regions of the world that experience Mediterranean climates. Messina has greater tolerance to the combined stresses of salinity and water-logging than existing commercial pasture legumes. Coupled with desirable agronomic traits these characteristics give messina the capacity to rehabilitate saltland and increase productivity on land where existing legumes fail. This paper reviews the agronomic perform-ance of messina in relation to top soil salinity levels
Influence of coronary artery disease on morbidity and mortality after abdominal aortic aneurysmectomy: A population-based study, 1971–1987
AbstractThe prognostic importance of coronary artery disease at the time of elective abdominal aortic aneurysmectomy was evaluated among 131 residents of Olmsted County, Minnesota who underwent elective aneurysmectomy from 1971 to 1987 and were followed up to 1988 for death and cardiac events (cardiac death, myocardial infarction, coronary bypass surgery and angioplasty). Before aneurysmectomy, 75 patients (Group 1) had no clinically recognized coronary disease, 47 patients (Group 2) had suspected or overt uncorrected coronary artery disease (history of prior myocardial infarction, angina or a positive stress test) and 9 patients (Group 3) had undergone coronary artery bypass grafting or coronary angioplasty.The 30 day operative mortality rate was 3% (2 of 75) in Group 1 and 9% (4 of 47) in Group 2 (p = 0.15). According to Kaplan-Meier analysis, estimated survival 8 years after aneurysmectomy was 59% (expected rate 68%, p = 0.29) in Group 1 versus 34% (expected rate 61%, p = 0.01) in Group 2. The cumulative incidence rate of cardiac events at 8 years was 15% and 61%, respectively, for patients without and with suspected/overt coronary artery disease (p < 0.01). Using multivariable proportional hazards analysis, uncorrected coronary artery disease was associated with a nearly twofold increased risk of death (hazard ratio 1.79, 95% confidence interval 1.06 to 3.00) and a fourfold increased risk of cardiac events (hazard ratio 3.71, 95% confidence interval 1.79 to 7.69).These population-based data support an aggressive lifelong approach to the management of coronary artery disease in patients undergoing abdominal aortic aneurysmectomy
Staphylococcus aureus infects osteoclasts and replicates intracellularly
Osteomyelitis (OM), or inflammation of bone tissue, occurs most frequently as a result of bacterial infection and severely perturbs bone structure. OM is predominantly caused b
SPECULOOS exoplanet search and its prototype on TRAPPIST
One of the most significant goals of modern science is establishing whether
life exists around other suns. The most direct path towards its achievement is
the detection and atmospheric characterization of terrestrial exoplanets with
potentially habitable surface conditions. The nearest ultracool dwarfs (UCDs),
i.e. very-low-mass stars and brown dwarfs with effective temperatures lower
than 2700 K, represent a unique opportunity to reach this goal within the next
decade. The potential of the transit method for detecting potentially habitable
Earth-sized planets around these objects is drastically increased compared to
Earth-Sun analogs. Furthermore, only a terrestrial planet transiting a nearby
UCD would be amenable for a thorough atmospheric characterization, including
the search for possible biosignatures, with near-future facilities such as the
James Webb Space Telescope. In this chapter, we first describe the physical
properties of UCDs as well as the unique potential they offer for the detection
of potentially habitable Earth-sized planets suitable for atmospheric
characterization. Then, we present the SPECULOOS ground-based transit survey,
that will search for Earth-sized planets transiting the nearest UCDs, as well
as its prototype survey on the TRAPPIST telescopes. We conclude by discussing
the prospects offered by the recent detection by this prototype survey of a
system of seven temperate Earth-sized planets transiting a nearby UCD,
TRAPPIST-1.Comment: Submitted as a chapter in the "Handbook of Exoplanets" (editors: H.
Deeg & J.A. Belmonte; Section Editor: N. Narita). 16 pages, 4 figure
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