On the use of a corresponding sequence algorithm for δ-fractions

AbstractThis paper discusses an algorithm for generating a new type of continued fraction, a δ-fraction, from a given power series. The δ-fraction corresponds to the given power series at z = 0. Included are convergence results and truncation error bounds

[17beta-Estradiol and testosterone influence the mRNA expression and the time course of inflammatory cytokines in activated human monocytic cell line (THP-1)].

Objective: The aim of this study was to evaluate the effects of 17b-estradiol (E2) and testosterone (T) on the mRNA expression of IL-1b, IL-6, TNF-a and TGF-b in cultured human monocytic cells (THP-1) after INF-g activation. Methods: THP-1 were cultured with E2 and T (10 nM) for 24 hs and then activated with INF-g (500 U/ml), during different periods of time (1, 3, 6, and 12 hs). After total RNA extraction, all samples were analyzed by multiple RT-PCR to detect mRNA expression of the selected cytokines. Results: Cells cultured without hormonal treatment expressed IL-1b mRNA after 1 h; on the contrary TNF-a, TGF-b and IL-6 mRNA were expressed only after 3 hs. At 6 and 12 hs only IL-6 mRNA was still expressed. Interestingly, cells cultured with testosterone never expressed IL-1b nor TNF-a mRNA and showed an IL-6 mRNA expression similar to the untreated controls at 3, 6 and 12 hours. On the contrary, cells treated with E2 showed the expression of all cytokines at 3 and 12 hs, and in general showed an higher expression of all the analyzed cytokines mRNA when compared to the other conditions. Conclusions: This study suggests that sex hormones may modulate the cytokine mRNA expression in the inflammatory cells. In fact, T inhibits TNF-a production at all the tested times, whereas E2 seems to accelerate and to enhance the inflammatory response. Therefore, the altered sex hormone ratio, as observed in the synovial fluid of RA patients (high E2/low T), might contribute to the occurrence and last of synovitis

AB0283 REDUCED HOSPITAL ADMISSION IN RA PATIENTS TAPERING BIOLOGIC DMARDS: PRELIMINARY ANALYSIS OF A RETROSPECTIVE STUDY

Background:bDMARDs are among the most effective therapies in the management of inflammatory arthritides, but they are associated with potentially severe adverse events (AEs), particularly infection. Tapering strategies of bDMARDs for patients in remission/low disease activity (R/LDA) have demonstrated comparable efficacy to standard-dose treatments, but their safety profile has not been studied yet.Objectives:To compare the number and the causes of hospital admissions in RA patients in R/LDA continuing or tapering bDMARDs.Methods:Consecutive patients with rheumatoid arthritis (RA) evaluated between 2011 and 2017, were assigned, based on treating physician's discretion, to continue the standard dose (STD) of bDMARDs or to undergo a predetermined tapering strategy (TAP), after being in R/LDA for two consecutive visits at least 3 months apart. Down-titration of bDMARDs was obtained by a stepwise increase of the dosing interval to achieve a reduction of about 30% (e.g. administration of etanercept every 10 days instead of weekly). Demographic, clinical data and concomitant treatments were retrospectively retrieved from the electronic charts of the outpatient clinics. Information about hospital admissions, including main diagnosis, period and duration of hospitalization, and death were retrieved from the Regional Healthcare System Database.For the STD group, the observation period started with the occurrence of remission and finished with one of these events: loss of remission, switch to another bDMARD, withdrawal of the bDMARD, severe AE, death, end of the study period in (December 2017). For the TAP group, the observation period started with tapering onset and finished with one of these events: reduction of the dosing interval due to either a relapse (according to a DAS28 increase) or to a subjective, symptomatic relapse (according to the patient's definition), switch to another bDMARD, withdrawal of the bDMARD, severe AE, death, end of the study period in (December 2017).Results:81 patients were included, of whom 40 underwent TAP. Demographic, clinical and treatment data are shown in table 1. Baseline characteristics were comparable between the two groups, except for the number of previous bDMARDs before observational period entry that was slightly higher in the STD group (STD 1.0±0.9 versus TAP 0.5±0.8, P=0.11).Table 1.Baseline demographic and clinical characteristics of the patients in remission or low disease activity.NO TAPERING(n=41)TAPERING(n=40)p valueMean age (yrs)57±1158±130.563Mean disease duration (yrs)12±912±70.897Starting bDMARD to tapering/monitoring (months)52±4567±410.128Mean monitoring period (months)22±2419±230.632Taking sDMARD at any time ((n (%))40 (98%)37 (92%)0.359Taking glucocorticoids29 (71%)28 (70%)0.999Mean prednisone dose (mg/day)2.5±2.92.1±2.70.527DAS28 at the time of tapering or first LDA/REM2.3±0.82.3±0.90.863Previous bDMARDs >1 (n (%))10 (24.4%)4 (10%)0.140In the STD group, 14 hospital admissions occurred, while in the TAP group there were 7 admissions (p=0.128). The corresponding figures for hospital admission due to infectious diseases were 6 in the STD group and 0 in the TAP group (p=0.026).Conclusion:Tapering bDMARDs in RA patients in R/LDA is associated with fewer hospital admissions, with a possible protective effect especially toward infections.Acknowledgments:The authors are indebted with Mrs Rosella Gramuglia and Mrs Cristina Olivieri for the management and analysis of the data on the flow of the drugs, and with Mrs Anna Consigliere, Mrs Anna Cosso, Mrs Romina Petralito and Mrs Laura Ravaschio for helping in retrieving clinical data.Disclosure of Interests:Dario Camellino Consultant of: I have received consultancy fees from Celgene, Sanofi, Novartis, Janssen-Cilag, Accord, Paid instructor for: I have served as a paid instructor for Mylan, Andrea Giusti Consultant of: UCB, Amgen, Janssen, Eli Lilly, Abiogen, EffRx, Speakers bureau: UCB, Amgen, Janssen, Eli Lilly, Abiogen, EffRx, Alfa-Sigma, Chiesi, Giuseppe Girasole: None declared, Chiara Craviotto: None declared, Paola Diana: None declared, Antonia Locaputo: None declared, Tiziana Caviglia: None declared, Lacramioara Luca: None declared, Gerolamo Bianchi Consultant of: Amgen, Janssen, Merck Sharp & Dohme, Novartis, UCB, Speakers bureau: Abbvie, Abiogen, Alfa-Sigma, Amgen, BMS, Celgene, Chiesi, Eli Lilly, GSK, Janssen, Medac, Merck Sharp & Dohme, Novartis, Pfizer, Roche, Sanofi Genzyme, Servier, UC

Transition probabilities for general birth-death processes with applications in ecology, genetics, and evolution

A birth-death process is a continuous-time Markov chain that counts the number of particles in a system over time. In the general process with $n$ current particles, a new particle is born with instantaneous rate $\lambda_n$ and a particle dies with instantaneous rate $\mu_n$. Currently no robust and efficient method exists to evaluate the finite-time transition probabilities in a general birth-death process with arbitrary birth and death rates. In this paper, we first revisit the theory of continued fractions to obtain expressions for the Laplace transforms of these transition probabilities and make explicit an important derivation connecting transition probabilities and continued fractions. We then develop an efficient algorithm for computing these probabilities that analyzes the error associated with approximations in the method. We demonstrate that this error-controlled method agrees with known solutions and outperforms previous approaches to computing these probabilities. Finally, we apply our novel method to several important problems in ecology, evolution, and genetics

Environmental assessment of maize production alternatives: Traditional, intensive and GMO-based cropping patterns

The evolution of maize production patterns in Argentina is evaluated over the last 25 years to compare costs, benefits, environmental performance and sustainability as well as to identify the main driving sources and improvement potential. Results from Argentina cropping systems are compared to other systems worldwide in order to put the Argentina results in a broader context. The study focuses on three farming categories: (1) traditional, low-intensity systems, (2) conventional, high-intensity systems, and (3) GMO-based cropping systems. Low input intensity systems include traditional cropping patterns with seed selection by farmers and conventional hybrid seed coupled to plowing and crop-animal rotation techniques; high input intensity systems use conventional hybrid seeds and recommended chemicals, irrigation and machinery with important soil erosion consequences; and GMO-based cropping systems use herbicide resistant transgenic hybrids, pesticides, higher fertilizer rates, and no-till practices. In each of the three cases, input flows are compared to the achieved yield (in mass and income terms) to better understand relative efficiencies and options for improvement. The study of GMO systems required a preliminary investigation of GMO seed production by seed companies, where a large investment in terms of prior knowledge and high-tech laboratory research is required. The assessments used the Emergy Accounting (EMA) approach. EMA includes material, energy, labor, money, and knowledge flows into the assessment and expands its focus over larger time and spatial scales than conventional economic and cumulative energy demand methods. Emergy-based environmental indicators of grain production for high-intensity hybrid and GMO systems both show a lower performance than low-intensity, traditional patterns in terms of resource return, renewability and sustainability. The fraction of renewability in low-intensity systems is between 28% and 63%, while it is between 8% and 26% for high-intensity hybrid and GMO systems. Calculated indicators also show that GMO-based maize production patterns do not guarantee the expected improvement over conventional high-intensity cropping systems or low-intensity systems in terms of performance and sustainability. Strong reliance on nonrenewable resources and technology, as well as role of direct and indirect labor costs are important factors in determining long-term sustainability and environmental stability of maize production systems

Variabilidad de la viabilidad y vigor de lotes de semillas de soja con presencia de simientes verdes pertenecientes a cultivares de distintos grupos de maduración producidos en dos fechas de siembra

Temperaturas superiores a los 32 ºC combinadas con estrés hídrico durante el llenado de granos de soja pueden provocar la aparición de semillas verdes. Estas simientes pueden ocasionar fallas en la germinación de los lotes, problemas durante el acondicionamiento y dificultades para el almacenamiento. Los objetivos del presente trabajo fueron determinar la calidad fisiológica de lotes de semillas de soja pertenecientes a distintos grupos de madurez, sembrados en dos fechas de siembras y con distintos contenidos de semillas verdes y estimar la viabilidad y el vigor de las semillas verdes. Se emplearon 5 lotes de semillas de cultivares de grupos de madurez III y IV sembrados tempranamente, con diferentes % de semillas verdes (4, 11, 16, 38 y 53%) y 5 lotes de grupo de madurez VI y VII sembrados tardíamente, con 3, 7, 11, 13 y 19% de semillas verdes. La calidad fisiológica fue evaluada mediante la Prueba Topográfica por Tetrazolio. Se utilizaron 4 repeticiones de 50 semillas para cada cultivar. El porcentaje de daño ambiental fue ≥ 52% en todos los cultivares. En las semillas de los grupos de madurez sembrados tempranamente los daños ambientales fueron extensos y ubicados en el eje embrionario. En las semillas de los grupos de madurez sembrados tardíamente, las lesiones ambientales fueron de poca extensión y superficiales. Las semillas verdes que permanecieron sin tinción en la PTT fueron clasificadas como no viables. Todos los materiales evaluados, presentaron un alto porcentaje de daño ambiental, siendo los cultivares de GM III y IV los que presentaron daños más críticos. Las semillas verdes pueden ser viables cuando el eje embrionario y la zona de unión de éste con los cotiledones no presentan daños profundos ni deterioro fisiológico