Comparison of five different methods to assess the concentration of boar semen

Both for research and practical purposes, accurate and repeatable methods are required to assess the concentration of boar semen samples. Since the method which is used may influence the results considerably, the aim of the present study was to compare 5 frequently used techniques to determine boar semen concentration. Fifty ejaculates were collected from 37 different boars at an artificial insemination centre. Subsequently, each ejaculate was analyzed for sperm concentration by means of 2 different types of colorimeters (Colorimeter 1: Model 252, Sherwood Scientific Ltd, Cambridge, UK; Colorimeter 2: Ciba-Corning, Schippers, Bladel, The Netherlands), the Burker counting chamber (golden standard), and the Hamilton Thorne Analyzer (Ceros 42.1) using 2 types of Leja chambers (the 'former' and the 'recently developed'). Each ejaculate was assessed 5 times with each of the 5 methods, and the repeatability, expressed by coefficient of variation (CV), was determined for each method. The different methods were compared using Pearson's correlations and limits of agreement. The colorimeters yielded the lowest CV's (both 3.7%), while the former Leja chamber resulted in the highest CV (12.4%). Moreover, significant (P0.71) were found between the results obtained by the different methods. The limits of agreement plots showed that none of the methods consistently over- or underestimated the sperm concentrations when compared to the Burker chamber, although there was a tendency toward higher over- or underestimation in highly concentrated sperm samples. Based on our results, there were no major differences in the assessment of sperm concentration between the evaluated methods. The choice of method used in a laboratory could therefore be based on factors such as cost, number of samples to be assessed and practical use, without thereby negatively affecting the validity of the results thus obtained

Electron Affinity Calculations for Thioethers

Previous work indicated that polyphenyl thioethers possessed chemical properties, related to their electron affinities, which could allow them to function as vapor phase lubricants (VPL). Indeed, preliminary tribological tests revealed that the thioethers could function as vapor phase lubricants but not over a wide temperature and hertzian pressure range. Increasing the electron affinity of the thioethers may improve their VPL properties over this range. Adding a substituent group to the thioether will alter its electron affinity in many cases. Molecular orbital calculations were undertaken to determine the effect of five different substituent groups on the electron affinity of polyphenyl thioethers. It was found that the NO2, F, and I groups increased the thioethers electron affinity by the greatest amount. Future work will involve the addition of these groups to the thioethers followed by tribological testing to assess their VPL properties

Detailed motility evaluation of boar semen and its predictive value for reproductive performance in sows

Reliable estimates of boar fertility potential from semen evaluation could be a valuable tool for boar selection. The aim of this study was to investigate the morphology and the detailed motility parameters of diluted boar semen and to relate these to their predictive value concerning conception and farrowing rate, litter size and the number of live born piglets. In addition, the optimal time for evaluation of the motility of preserved semen with respect to its predictive effect on fertility was determined. One hundred ejaculates from 38 boars were evaluated morphologically by eosin-nigrosin staining and different motility characteristics were assessed using Computer Assisted Semen Analysis (CASA). The motility was determined at 15, 45 and 120 minutes after incubation at 37 degrees C. The conception rate, farrowing rate, litter size and number of live born piglets were registered from 276 sows inseminated with these ejaculates. Different regression models were used to evaluate the predictive value of the semen characteristics on these fertility parameters, taking into account the effect of herd, parity and weaning to estrus interval. The motility characteristics of the spermatozoa varied significantly during the 15 to 120 minutes of incubation. The longer the incubation time, the more the velocity parameters along the actual cell path decreased, while the parameters of straightforward movement increased. The predictive value of individual semen parameters on conception and farrowing rate was very small. The predictive value of certain associations of different semen parameters, on the other hand, was significant. The percentage of motile spermatozoa had a significant (P<0.05) and positive effect on the total number of piglets born (litter size) and on the number of live born piglets, independent of the time of measurement (X-2 0.38-1.00 and 0.41-1.00, respectively). Accurate evaluation of the motility of a semen dose is therefore imperative for estimating its predictive value relating to fertility. In conclusion, since the time of evaluation after warming the samples significantly influences the motility parameters, CASA measurement should be done when the cells are completely acclimatized to 37 degrees C. On the basis of the available data, a 45 min incubation period appeared to be sufficient. The percentage of motile spermatozoa, as assessed by CASA on diluted semen, offers detailed predictive information regarding litter size, irrespective of the time of measurement

R1507, an Anti-Insulin-Like Growth Factor-1 Receptor (IGF-1R) Antibody, and EWS/FLI-1 siRNA in Ewing's Sarcoma: Convergence at the IGF/IGFR/Akt Axis

A subset of patients with Ewing's sarcoma responds to anti-insulin-like growth factor-1 receptor (IGF-1R) antibodies. Mechanisms of sensitivity and resistance are unknown. We investigated whether an anti-IGF-1R antibody acts via a pathway that could also be suppressed by small interfering (si) RNA against the EWS/FLI-1 fusion protein, the hallmark of Ewing's sarcoma. The growth of two Ewing's sarcoma cell lines (TC-32 and TC-71) was inhibited by the fully human anti-IGF-1R antibody, R1507 (clonogenic and MTT assays). TC-32 and TC-71 cells express high levels of IGF-2, while RD-ES and A4573 Ewing's cell lines, which were less responsive to R1507 in our assays, express low or undetectable IGF-2, respectively. TC-71 cells also expressed high levels of IGF-1R, and R1507 decreased steady-state levels of this receptor by internalization/degradation, an effect which was associated with a decrease in p-IGF-1R, p-IRS-1, and p-Akt. EWS/FLI-1 siRNA also decreased p-Akt, due to its ability to increase IGF-BP3 levels and subsequently decrease IGF-1 and IGF-2 levels, thus inhibiting signaling through p-IGF-1R. This inhibition correlated with growth suppression and apoptosis. The attenuation of Akt activation was confirmed in TC-71 and HEK-293 (human embryonic kidney) cells by transfecting them with IGF-1R siRNA. We conclude that antibodies and siRNA to IGF-1R, as well as siRNA to EWS/FLI-1, act via intersecting IGF/IGF-1R signals that suppress a common point in this pathway, namely the phosphorylation of Akt

Pediatric T- and NK-cell lymphomas: new biologic insights and treatment strategies

T- and natural killer (NK)-cell lymphomas are challenging childhood neoplasms. These cancers have varying presentations, vast molecular heterogeneity, and several are quite unusual in the West, creating diagnostic challenges. Over 20 distinct T- and NK-cell neoplasms are recognized by the 2008 World Health Organization classification, demonstrating the diversity and potential complexity of these cases. In pediatric populations, selection of optimal therapy poses an additional quandary, as most of these malignancies have not been studied in large randomized clinical trials. Despite their rarity, exciting molecular discoveries are yielding insights into these clinicopathologic entities, improving the accuracy of our diagnoses of these cancers, and expanding our ability to effectively treat them, including the use of new targeted therapies. Here, we summarize this fascinating group of lymphomas, with particular attention to the three most common subtypes: T-lymphoblastic lymphoma, anaplastic large cell lymphoma, and peripheral T-cell lymphoma-not otherwise specified. We highlight recent findings regarding their molecular etiologies, new biologic markers, and cutting-edge therapeutic strategies applied to this intriguing class of neoplasms

Comparison of 5 different methods for the assessment of boar semen concentration

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