Evidence-based medicine: quality and comparability of clinical trials investigating the efficacy of prostaglandin F(2α) 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).     

Neutron radiography and current distribution measurements for studying cathode flow field properties of direct methanol fuel cells

The influence of the cathode flow field properties on the water distribution and performance of direct methanol fuel cells (DMFCs) was studied. All measurements were performed with DMFC stack cells (A = 314.75 cm²). The local and temporal water distributions in the flow field channels during DMFC operation were visualized by means of through‐plane neutron radiography. Current and temperature distributions were measured simultaneously by the segmented cell technology. Additionally, the time‐dependent current distribution, cell performance and pressure drop were measured. Cathode flow field designs with channel and grid structures were compared. The cathode flow field channels were impregnated by either hydrophobizing or hydrophilizing agents or used as received. It turned out that hydrophobized and partially also untreated flow fields cause large water droplets in the cathode channels. The water droplets cause a blocking of the air flow and consequently a lower and more unstable (fluctuating) performance, less steady current and temperature distributions, and higher pressure drops between cathode inlet and outlet. Because of their two‐dimensional design, grid flow fields are less prone to water accumulations. The best results are achieved with a hydrophilized grid flow field that has a channel depth and width of 1.5 mm each (‘C‐GR15’). Copyright © 2013 John Wiley & Sons, Ltd.     

Reverse-phase protein arrays for application-orientated cancer research

A detailed and quantitative analysis of disease-relevant signaling will greatly contribute to our understanding of tumorigenesis and cancer progression, and thus open new strategies for drug discovery. However, throughput and sensitivity of currently established methods available for proteome profiling do not comply with the needs of clinical research such as high sample capacity and low sample consumption. Protein microarrays emerged as a promising alternative to analyze the abundance of proteins and their phosphorylation status on a high-throughput level. Here we summarize recent methodological advancements in the field of reverse-phase protein arrays and demonstrate their potential for clinical research as well as for in vitro applications.     

Twinning in ferroelectric and ferroelastic ceramics: stress relief

The regular twinning in ceramics and metals below the temperature of a ferroelastic or ferroelectric structural phase transition is a result of energy minimization. Here homogeneous elastic energy is reduced at the expense of twin wall energy. The twin density depends on the gram sizeg; under homogeneous stress the total elastic energy of a grain increases g ³. Any kind of twin wall, however, increases g ². Below the intersection of these two curves, stress reduction by twinning cannot lower the total energy. Thus there is a critical grain size below which twinning should not occur. Above this limit the width of the twin lamellae increases g ^1/2. The shape of the grain then adjusts to the surroundings in two dimensions only. Above another larger critical grain size more complex interfaces with higher surface energy are created, which allow stress relief in the third dimension. A semi-quantitative model is developed with the example of BaTiO₃ ceramic, of which the domain patterns are well known. It is representative for many ceramics. The highT _c superconductor YBa₂Cu₃O_7– also twins according to the same law. For three-dimensional adjustment here a proper interface is missing.     

Efficacy of homeopathic remedies as prophylaxis of bovine endometritis

The objective of this study was to evaluate the efficacy of 2 different homeopathic prophylactic strategies for the prevention of endometritis. The drugs used were Lachesis compositum (Lachesis), Carduus compositum (Carduus), and Traumeel LT (Traumeel). Each drug contained a mixed formula of homeopathic remedies. All 929 cows received the first treatment within 24 h postpartum. The second to fourth treatments were conducted at 7 to 13, 14 to 20, and 21 to 27 d in milk, respectively. In the first group, the 4 treatments were Traumeel, Lachesis, Carduus, and Carduus, respectively (n = 206). In the second group, Lachesis was administered 3 times, followed by 1 treatment with Carduus (n = 198). The control group received 4 injections of saline (n = 189). In the fourth week after calving, the prevalence of clinical endometritis, uterine involution, and ovarian activity was monitored by rectal palpation and by ultrasonography. To assess the resumption of ovarian activity, blood samples were taken to determine the concentration of serum progesterone. The concentrations of β-hydroxybutyrate and nonesterified fatty acids in blood serum were examined to evaluate energy metabolism. The incidence of clinical endometritis at 21 to 27 d in milk did not differ between the groups (44.4, 44.8, and 36.9% in the Traumeel, Lachesis, Carduus, and Carduus group; the 3× Lachesis, followed by Carduus group; and the control group, respectively). The proportion of cows with cyclic activity at 21 to 27 d in milk and the proportion of cows above threshold values of progesterone, β-hydroxybutyrate, and nonesterified fatty acids did not differ significantly between groups. When reproductive performance data were analyzed, no significant differences were found between groups. Hence, the treatment protocols tested were not effective in preventing bovine endometritis or in enhancing reproductive performance in this study.     

Partition Coefficients of Alkyl Parabens and Ibuprofen in Micellar Systems

The partitioning of alkyl parabens and ibuprofen in aqueous solutions of nonionic and ionic surfactants is studied experimentally and via a priori predictions using the COSMO‐RS model. The effects of organic (Bu₄NBr) and inorganic (NaCl) electrolytes are examined. Addition of NaCl results in a slight increase in the partition coefficients of parabens in solutions of octylphenolpoly(ethyleneglycolether) and a more pronounced increase in the sodium dodecyl sulfate (SDS) system. The partition coefficients of ibuprofen increase on addition of NaCl to aqueous solutions of SDS and decrease if Bu₄NBr is added to dodecyl trimethyl ammonium bromide (DTAB) solutions. Good agreement between experimental and calculated data shows a high potential of COSMO‐RS in the prediction of micelle/water partition coefficients in the presence of electrolytes and makes it a valuable tool in drug and drug‐carrier design as well as in optimizing micellar reactions or micelle‐enhanced separation processes.