The accessory bacteriochlorophyll

The primary electron transfer in reaction centers of Rhodobacter sphaeroides is studied by subpicosecond absorption spectroscopy with polarized light in the spectral range of 920-1040 nm. Here the bacteriochlorophyll anion radical has an absorption band while the other pigments of the reaction center have vanishing ground-state absorption. The transient absorption data exhibit a pronounced 0.9-ps kinetic component which shows a strong dichroism. Evaluation of the data yields an angle between the transition moments of the special pair and the species related with the 0.9-ps kinetic component of 26 +/- 8 degrees. This angle compares favorably with the value of 29 degrees expected for the reduced accessory bacteriochlorophyll. Extensive transient absorbance data are fully consistent with a stepwise electron transfer via the accessory bacteriochlorophyll

a meta-analysis

The objective of the conducted meta-analysis was to assess the efficacy of the treatment of bovine endometritis with PGF(2α) by statistical means. Postpartum uterine infections have a high prevalence and a very negative effect on reproductive performance in dairy cattle. Because of a wide discordance between research results, a meta-analysis of the efficacy of the treatment of bovine endometritis with PGF(2α) was conducted. A comprehensive literature search was performed using online databases to reveal a total of 2,307 references. In addition, 5 articles were retrieved by reviewing citations. After applying specific exclusion criteria and evaluating specific evidence parameters, 5 publications, comprising 6 trials, were eligible for being analyzed by means of meta-analysis. Data for each trial were extracted and analyzed using meta-analysis software Review Manager (version 5.1; The Nordic Cochrane Centre, Copenhagen, Denmark). Estimated effect sizes of PGF(2α) were calculated on calving to first service and calving to conception interval. Prostaglandin F(2α) treatment of cows with chronic endometritis had a negative effect on both reproductive performance parameters. Heterogeneity was substantial for calving to first service and calving to conception interval [I(2) (measure of variation beyond chance)=100 and 87%, respectively]; therefore, random-effects models were used. Sensitivity analysis as well as subgroup analysis showed that the performance of randomization was influential in modifying effect size of PGF(2α) treatment. The funnel plot illustrated a publication bias toward smaller studies that reported a prolonged calving to conception interval after a PGF(2α) treatment. We conclude that the investigation of this subject by means of meta-analysis did not reveal an improvement of reproductive performance of cows with endometritis after treatment with PGF(2α). Furthermore, there is a shortage of comparable high quality studies investigating reproductive performance after PGF(2α) treatment of cows with chronic endometritis

quality and comparability of clinical trials investigating the efficacy of prostaglandin F2α for the treatment of bovine endometritis

The objective of this study was to evaluate the quality and comparability of published literature, and to summarize the effect of prostaglandin F(2α) (PGF(2α)) for the treatment of endometritis. It has been postulated that there is a dearth of high-level evidence-based research results in veterinary medicine. Also, there is a marked variation in the quality of studies in veterinary and animal science. Post-partum uterine infections occur commonly in dairy cattle and are reported to have a negative impact on reproductive performance. A comprehensive literature search was conducted utilizing online databases revealing a total of 2723 references. After applying specific exclusion criteria, a total of 68 trials were eligible for further analysis. These articles were evaluated utilizing specific parameters listed in an evaluation form such as randomization and the involvement of control groups. The analysis revealed that more than half of the trials (51·5%) were at least 20 years old. Furthermore, we found that about one third (36·8%) of all trials were controlled and randomized, while 3 of those (4·4%) were also blinded. Of those trials which calculated a calving-to-conception interval (n=30), 50% of the authors claimed an improvement, which was statistically significant in 23·3% of the cases. We conclude that there is a wide discrepancy between research results investigating the efficacy of PGF(2α)

A critical evaluation of diagnostic methods used to identify dairy cows with acute post-partum metritis in the current literature

The overall objective of this study was to investigate how relevant research publications address the validity of diagnostic methods for acute puerperal metritis (APM) in dairy cows, a disease commonly treated with antibiotic drugs. Therefore, a literature search was conducted in Journal of Dairy Science, Theriogenology, Animal Reproduction Science and The Veterinary Journal utilizing the ScienceDirect database. The search revealed 259 articles addressing APM. After applying exclusion criteria, a total of 48 trials remained. It was determined whether the author gave a clear definition of APM, the time of diagnosis relative to calving, and the person who performed the diagnosis. Studies were checked for the presence of definitions of possible findings, thresholds, and test characteristics of the methods used. Overall 9 different diagnostic methods were employed. On average 2·5 ± 1·75 diagnostic methods were used in a study. References to support the use of the diagnostic methods were provided in 10 of 48 articles (20·8%). Vaginal discharge, transrectal palpation and rectal temperature were examined in 39, 22, and 21 of the studies, respectively. Thresholds for diagnostic tests and test characteristics were mentioned in 6 and 3 of the 48 articles, respectively. Based on this systematic review of 48 research papers the evidence supporting the use of the diagnostic methods to identify cows with APM has either been not reported or is weak. In conclusion, the reporting of the diagnostic methods to identify cows with APM needs to be improved and further high- quality research is necessary to improve diagnostic performance of the methods employed

The promoter of human p22/PACAP response gene 1 (PRG1) contains functional binding sites for the p53 tumor suppressor and for NFκB

AbstractWe describe functional binding sites for the tumor suppressor p53 and for NFκB residing in the promoter of the novel human early response gene p22/PRG1 (IEX-1/DIF-2). Gel shift and supershift assays demonstrate binding of p53 and NFκB to their corresponding sites in vitro. CAT-reporter gene assays show transactivation of the human p22/PRG1 promoter by p53 in Hep3B cells stably transfected with a temperature-sensitive mutant p53, but not in p53-deficient Hep3B cells. TNFα induced NFκB dependent transactivation was shown in HepG2 cells or in 818-4 pancreatic cancer cells. These data imply that human p22/PRG1 is a target gene for p53 and NFκB involved in growth regulation and stress response

Spontaneous symmetry breaking in spinor Bose-Einstein condensates

We present an analytical model for the theoretical analysis of spin dynamics and spontaneous symmetry breaking in a spinor Bose-Einstein condensate (BEC). This allows for an excellent intuitive understanding of the processes and provides good quantitative agreement with experimental results in Phys. Rev. Lett. 105, 135302 (2010). It is shown that the dynamics of a spinor BEC initially prepared in an unstable Zeeman state mF=0 (|0>) can be understood by approximating the effective trapping potential for the state |+-1> with a cylindrical box potential. The resonances in the creation efficiency of these atom pairs can be traced back to excitation modes of this confinement. The understanding of these excitation modes allows for a detailed characterization of the symmetry breaking mechanism, showing how a twofold spontaneous breaking of spatial and spin symmetry can occur. In addition a detailed account of the experimental methods for the preparation and analysis of spinor quantum gases is given.Comment: 12 pages, 14 figure

Statistical methods and software for the analysis of highthroughput reverse genetic assays using flow cytometry readouts

Highthroughput cell-based assays with flow cytometric readout provide a powerful technique for identifying components of biologic pathways and their interactors. Interpretation of these large datasets requires effective computational methods. We present a new approach that includes data pre-processing, visualization, quality assessment, and statistical inference. The software is freely available in the Bioconductor package prada. The method permits analysis of large screens to detect the effects of molecular interventions in cellular systems