New Water Disinfectant: an Insoluble Quaternary Ammonium Resin-Triiodide Combination that Releases Bactericide on Demand

Strongly basic anion-exchange resins form stable, water-insoluble combinations with triiodide ions. The combinations have remarkable antibacterial properties: 3.0 x 10(5)Escherichia coli cells per ml were killed when passed through a 3.8-g column of commercially available resin treated with triiodide (volume 4 ml after treatment). In an attempt to deplete the resin-triiodide complex, 1.14 x 10(9)E. coli cells in 15 liters were passed through the column with no significant loss of effectiveness. The antibacterial capabilities of the resin-triiodide columns ranged from 10(6)Salmonella typhimurium per ml to 1.1 x 10(4)Streptococcus faecalis per ml. Staphylococcus aureus and Pseudomonas aeruginosa were also tested and killed at concentrations of 1.8 x 10(4) and 1.3 x 10(5) per ml, respectively. The cells were not filtered from the water. They emerged from the column in nonviable form. This was demonstrated by using (14)C-labeled bacteria. The irreversible nature of the antibacterial action was revealed when attempts to wash the damaged cells did not restore viability.     

Improved pregnancy and birth rates with routine application of nonsurgical embryo transfer

Nonsurgical embryo transfer (NSET) of blastocysts to pseudopregnant female recipients provides many benefits over surgical implantation with less distress for the mice, no anesthesia or analgesia required and a considerable reduction in implantation time per mouse. Although a disposable device to perform NSET is on the market since 2009, it is not generally used in transgenic facilities, most likely because surgical implantation is efficient and inexpensive. Here, we report that with several refinements to the original protocol, the NSET method becomes very attractive and outperforms the traditional surgical transfer on basis of pregnancy rate, birth rate and implantation-related discomfort. Furthermore, repeated use of the same NSET device on several recipient females reduces the costs to a reasonable level. The data presented covers all embryo transfers over the last 5 years at the transgenic facility of the Netherlands Cancer Institute, of which the last 2 years were performed exclusively with NSET.     

Efficacy of a pentaiodide resin disinfectant on Cryptosporidium parvum (Apicomplexa: Cryptosporidiidae) oocysts in vitro

The resin-I5 column developed at Kansas State University was tested for efficacy against oocysts of Cryptosporidium parvum (Apicomplexa: Cryptosporidiidae). Cesium chloride gradient-purified oocysts were passed through 1.0-cm-diameter columns with lengths of 2.5, 5.0, and 10.0 cm at 23 C. Following column passage, oocyst viability was determined both in vitro by excystation and in vivo by the ability to establish infections in suckling mice. Oocysts were found to be retained by the pentaiodide resin in a linear fashion, probably by electrostatic interactions. Linear regression analysis revealed 100% of the oocysts should be removed in such a manner using a column length of greater than or equal to 25.7 cm. When compared to untreated control oocysts, less than 12% of the oocysts that passed through the columns appeared to be affected by the resin, as assessed by excystation. Inoculation of suckling mice with these column-treated oocysts supported the excystation data and revealed the coccidian to be viable. These results indicate that oocysts of C. parvum are retained on the pentaiodide column in a 1-hit manner and that, although killing of parasites may occur within the column, the greatest effect that the column may have on the parasite is as an electrostatic retention device.     

Giant congenital melanocytic nevus with vascular malformation and epidermal cysts associated with a somatic activating mutation in BRAF

Giant congenital melanocytic nevi may be symptomatically isolated or syndromic. Associations with capillary malformations are exceptional, and development of epidermal cysts has not been described. A 71‐year‐old patient with a giant congenital melanocytic nevus (CMN) of the lower back, buttocks, and thighs was asymptomatic except for unexpected hemorrhage during partial surgical excision years before. Blunt trauma at age 64 initiated recurrent, severe pain under the nevus; multiple large epidermal cysts then developed within it. Imaging and biopsy showed a large, non‐pulsatile venous malformation intermingled with the deep nevus. A low‐abundance, heterozygous BRAF c.1799T>A (p.V600E) mutation was present in both gluteal and occipital congenital nevi; additional mutations in NRAS, GNAQ, GNA11, HRAS, or PIK3CA were undetectable. This is the first demonstration of a recurrent BRAF mutation in multiple large congenital nevi from the same individual, confirming that this malformation can have multiple genetic origins. Early constitutive activation of BRAF can therefore cause unusual associations of giant nevi with vascular malformations, indicating that both pigment and endothelial cell physiology may be affected by mosaic RASopathies.     

Carbonic anhydrase activity in leaves as measured in vivo by18O exchange between carbon dioxide and water

Carbonic anhydrase activity of intactCommelina communis L. leaves was measured using mass spectrometry, by following the¹⁸O-exchange kinetics between¹⁸O-enriched carbon dioxide and water. A gas-diffusion model (Gerster, 1971, Planta97, 155–172) was used to interpret the¹⁸O-exchange kinetics and to determine two constants, one (k) related to the hydration of CO₂ and the other (k_e), related to the diffusion of CO₂. Both constants were determined inCommelina communis L. leaves after stripping the lower epidermis to remove any stomatal influence. The hydration constant (k) was 17200 +2200 ·min^–1 (mean±SD, 12 experiments), i.e., about 8 600 times the uncatalyzed hydration of CO₂ in pure water, and was specifically inhibited by ethoxyzolamide, a powerful inhibitor of carbonic anhydrases, half-inhibition occurring around 10^–5 Methoxyzolamide. The diffusion constant (k_e) was 1.18±0.28·min^–1 (mean±SD, 12 experiments) and was only slightly inhibited (about 20%) by ethoxyzolamide. Carbonic anhydrase activity of stripped leaves was not affected by the leaf water status (up to 50% relative water deficits), was strongly inhibited by monovalent anions such as Cl^– or NO ₃ ^– , and decreased by about 50% when the photon flux density during growth was increased from 100 to 500 mol photons·m^–2·s^–1. By studying the effect of ethoxyzolamide (10^–4 M) on photosynthetic O₂ exchange, measured using¹⁸O₂ and mass spectrometry, we found that inhibition of carbonic anhydrase activity by 92–95% had little effect on the response curves of net O₂ evolution to increased CO₂ concentrations. Ethoxyzolamide had no effect on the photosynthetic electron-transport rate, measured as gross O₂ photosynthesis at high CO₂ concentration (>350 l·^–1), but was found to increase both gross O₂ photosynthesis and O₂ uptake at lower CO₂ levels. The chloroplastic CO₂ concentration calculated from O₂-exchange data was not significantly modified by ethoxyzolamide. We conclude from these results that, under normal conditions of photosynthesis, most of the carbonic anhydrase activity is not involved in CO₂ assimilation. Measurement of carbonic anhydrase activity using¹⁸O-isotope exchange therefore provides a suitable model to study the in-vivo regulation of this chloroplastic enzyme in plants submitted to various environmental conditions.Abbreviations CA carbonic anhydrase - C_cc chloroplastic CO₂ concentration - C_e external CO₂ concentration - EZA ethoxyzolamide - k CO₂ hydration rate constant - k_e CO₂ diffusion rate constan - PPFD photosynthetic photon flux density - Rubisco ribulose-1,5 bisphosphate carboxylase oxygenase - RWD relative water deficit The authors wish to thank P. Carrier for technical assistance with mass-spectrometric experiments and Dr. P. Thibault for helpful suggestions and comments. Dr. A. Vavasseur is gratefully acknowledged for supplyingCommelima communis. cultures. P.C., P.T. and A.V. are all from the CEA, Département de Physiologie Végétale et Ecosystèmes, Cadarache, France.     

BRCA2 protein deficiency exaggerates doxorubicin-induced cardiomyocyte apoptosis and cardiac failure

The tumor suppressor breast cancer susceptibility gene 2 (BRCA2) plays an important role in the repair of DNA damage, and loss of BRCA2 predisposes carriers to breast and ovarian cancers. Doxorubicin (DOX) remains the cornerstone of chemotherapy in such individuals. However, it is often associated with cardiac failure, which once manifests carries a poor prognosis. Because BRCA2 regulates genome-wide stability and facilitates DNA damage repair, we hypothesized that loss of BRCA2 may increase susceptibility to DOX-induced cardiac failure. To this aim, we generated cardiomyocyte-specific BRCA2 knock-out (CM-BRCA2(-/-)) mice using the Cre-loxP technology and evaluated their basal and post-DOX treatment phenotypes. Although CM-BRCA2(-/-) mice exhibited no basal cardiac phenotype, DOX treatment resulted in markedly greater cardiac dysfunction and mortality in CM-BRCA2(-/-) mice compared with control mice. Apoptosis in left ventricular (LV) sections from CM-BRCA2(-/-) mice compared with that in corresponding sections from wild-type (WT) littermate controls was also significantly enhanced after DOX treatment. Microscopic examination of LV sections from DOX-treated CM-BRCA2(-/-) mice revealed a greater number of DNA double-stranded breaks and the absence of RAD51 focus formation, an essential marker of double-stranded break repair. The levels of p53 and the p53-related proapoptotic proteins p53-up-regulated modulator of apoptosis (PUMA) and Bax were significantly increased in samples from CM-BRCA2(-/-) mice. This corresponded with increased Bax to Bcl-2 ratios and elevated cytochrome c release in the LV sections of DOX-treated CM-BRCA2(-/-) mice. Taken together, these data suggest a critical and previously unrecognized role of BRCA2 as a gatekeeper of DOX-induced cardiomyocyte apoptosis and susceptibility to overt cardiac failure. Pharmacogenomic studies evaluating cardiac function in BRCA2 mutation carriers treated with doxorubicin are encouraged.     

Connectedness among herds of beef cattle bred under natural service

Background

A procedure to measure connectedness among herds was applied to a beef cattle population bred by natural service. It consists of two steps: (a) computing coefficients of determination (CDs) of comparisons among herds; and (b) building sets of connected herds.

Methods

The CDs of comparisons among herds were calculated using a sampling-based method that estimates empirical variances of true and predicted breeding values from a simulated n-sample. Once the CD matrix was estimated, a clustering method that can handle a large number of comparisons was applied to build compact clusters of connected herds of the Bruna dels Pirineus beef cattle. Since in this breed, natural service is predominant and there are almost no links with reference sires, to estimate CDs, an animal model was used taking into consideration all pedigree information and, especially, the connections with dams. A sensitivity analysis was performed to contrast single-trait sire and animal model evaluations with different heritabilities, multiple-trait animal model evaluations with different degrees of genetic correlations and models with maternal effects.

Results

Using a sire model, the percentage of connected herds was very low even for highly heritable traits whereas with an animal model, most of the herds of the breed were well connected and high CD values were obtained among them, especially for highly heritable traits (the mean of average CD per herd was 0.535 for a simulated heritability of 0.40). For the lowly heritable traits, the average CD increased from 0.310 in the single-trait evaluation to 0.319 and 0.354 in the multi-trait evaluation with moderate and high genetic correlations, respectively. In models with maternal effects, the average CD per herd for the direct effects was similar to that from single-trait evaluations. For the maternal effects, the average CD per herd increased if the maternal effects had a high genetic correlation with the direct effects, but the percentage of connected herds for maternal effects was very low, less than 12%.

Conclusions

The degree of connectedness in a bovine population bred by natural service mating, such as Bruna del Pirineus beef cattle, measured as the CD of comparisons among herds, is high. It is possible to define a pool of animals for which estimated breeding values can be compared after an across-herds genetic evaluation, especially for highly heritable traits.     

Non-Thermal Plasmas Affect Plant Growth and DNA Methylation Patterns in Glycine max

Journal of Plant Growth Regulation - Non-thermal plasmas (NTP) are partially ionized gases that represent a promising technology for seed treatment to enhance seed health while promoting...     

Molecular profile of androgen-independent prostate cancer xenograft LuCaP 23.1

After castration or therapeutic hormone deprivation, most cancer of the prostate (CaP) cells develop androgen-independent (AI) growth. In this work, we studied the effect of androgen depletion (castration) on the growth of experimental model LuCaP 23.1 xenograft. A total of 101 nude mice were implanted and analysed for their growth profile before experimental period 1 (11 weeks) and after castration experimental period 2 (15 weeks). For specific periods, tumors were harvested and assessed for molecular marker expression specific for CaP. Taking into account tumor dynamic growth, prior to castration we found 37 fast growing (FG) tumors (948.9 ± 76.9 mm³) and 63 slow growing (SG) tumors (229.6 ± 18.4 mm³). Real-time quantitative RT-PCR showed that in comparison to SGs, FGs contained elevated expression of epidermal growth factor receptor type 1 (HER1), urokinase plasminogen activator (uPA), thymidine phosphorylase (TP) and thymidilate synthase (TS) mRNAs expression and low levels of 5-reductase 2 (5-R2) mRNA. After castration all FG tumors progressed rapidly (by 5 weeks) to AI growth (FG-P). In SG castrated tumors, 66% of tumors showed retarded progression (by 12 weeks) to AI (SG-P), whereas 34% responded to castration (SG-R). Molecular analysis demonstrated distinct molecular profiles integrating different pathways associated with AI progression. The progressive tumors FG-P, and some tumors of SG-P subgroup, presented significantly high levels of HER1, epidermal growth factor receptor type 2 (HER2), TS, uPA, TP, tumor necrosis factor superfamily member 6 (FAS) and peptidylglycine -amidating mono-oxygenase (PAM) mRNA all of which correlated with androgen receptor (AR) mRNA. The second subgroup of SG-P tumors showed a high expression of the anti-apoptotic gene Bcl-2. A third subgroup of SG-P tumors showed significant expression of hypoxia-related genes such as adrenomedullin (AM) after castration. LuCaP 23.1 xenograft represent a useful dynamic model to study pre-clinically new therapeutic molecules and evaluate non-randomized therapeutics protocols combining different target inhibition specific to each AI pathways.