Human seminal vesicle-specific antigen is a substrate for prostate-specific antigen (or P-30)

Human seminal vesicle and prostatic fluids were obtained separately and reconstituted in vitro to test the hypothesis that proteolytic enzymes of prostatic origin would degrade seminal vesicle-specific antigen (SVSA). Using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and immunoblot analysis to follow the fate of SVSA over time, we found that upon mixing the two secretions, SVSA was converted to forms of intermediate and low molecular weight identical to transformations seen in normal liquefied ejaculates. Diisoproprylfluorophophate, a serine protease inhibitor, prevented this degradation, indicating serine protease involvement in the proteolysis of SVSA. Prostate-specific antigen (PSA; also known as P-30), recently identified as a serine protease, was examined for its ability to mimic the effects of prostatic fluid on SVSA. Purified PSA catalyzed degradation of SVSA to produce proteolytic fragments that comigrated and were immunologically related to SVSA fragments produced by prostatic fluid. Purified PSA in the presence of serine protease inhibitors was unable to degrade SVSA. These results demonstrate that SVSA is a substrate for PSA during human semen liquefaction.     

Versammlung des zoologisch-botanischen Vereines zu Wien am 2. Juli d. J.

Ohne Zusammenfassung     

Heterobiaryl purine derivatives as potent antiproliferative agents: Inhibitors of cyclin dependent kinases. Part II

C-6 Biarylmethylamino purine derivatives of roscovitine (1) inhibit cyclin dependent kinases and demonstrate potent antiproliferative activity. Replacement of the aryl rings of the C-6 biarylmethylamino group with heterobiaryl rings has provided compounds with significantly improved activity. In particular, derivatives 18g and 9c demonstrated 1000-fold and 1250-fold improvements, respectively, in the growth inhibition of HeLa cells compared to roscovitine (1).     

A single molecule assay for measuring site-specific DNA cleavage

Sequence-specific DNA cleavage is a key step in a number of genomic transactions. Here, we report a single-molecule technique that allows the simultaneous measurement of hundreds of DNAs, thereby collecting significant statistics in a single experiment. Microbeads are tethered with single DNA molecules in a microfluidic channel. After the DNA cleavage reaction is initiated, the time of cleavage of each DNA is recorded using video microscopy. We demonstrate the utility of our method by measuring the cleavage kinetics of NdeI, a type II restriction endonuclease.     

Incorporation of ascorbic acid and α-tocopherol to the extender media to enhance antioxidant system of cryopreserved sea bass sperm

Despite the overwhelming application of sperm cryopreservation in aquaculture and broodstock management, its detrimental effects on sperm quality must be taken into account. Imbalance of reactive oxygen species is considered one of the main triggers of cell damage after cryopreservation, because the spermatozoa antioxidant system is decimated during this process, mainly because the natural antioxidants present in seminal plasma diminish when sperm is diluted in extenders. It has been demonstrated that the addition of antioxidants to the extender improves the quality of thawed sperm. Thus, the aim of the present work was to evaluate the status of the antioxidant system in cryopreserved sea bass sperm, and the possibility of enhancing this system to reduce oxidation of the membrane compounds by extender supplementation with vitamins. To do this, sperm from European sea bass (Dicentrarchus labrax) was cryopreserved using an extender control (NAM), supplemented with 0.1 mm α-tocopherol or 0.1 mm ascorbic acid. Sperm motility (computer assisted sperm analysis (CASA) parameters), viability (SYBR Green/propidium iodide (PI)), lipid peroxidation (malondialdehyde (MDA) levels) and protein oxidation (DNPH levels) were analyzed, as well as the status of the sperm antioxidant system by determining glutathione peroxidase, glutathione reductase and superoxide dismutase (GPX, GSR and SOD) activity. The results demonstrated that extenders containing vitamins significantly increased sperm motility. Total motility, velocity and linearity increased from 31.2 ± 3.0 μm/sec, 18.3 ± 1.7 μm/sec and 46.9 ± 2.0% in extender containing 0.1 mm α-tocopherol or 30.6 ± 3.9 μm/sec, 19.5 ± 1.6 μm/sec and 47.9 ± 2.2% in extender containing 1 mm ascorbic acid respect to the extender control (20.7 ± 3.3 μm/sec, 13.8 ± 1.7 μm/sec and 37.3 ± 4.1%). However, viability and levels of lipid peroxidation and protein oxidation were not affected by the presence of these antioxidants, suggesting that membrane impairment could be more associated to osmotic shock or membrane destabilization than oxidative damage. The increased activity of both GPX and GSR after cryopreservation showed that the antioxidant system of sea bass sperm must play an important role in preventing oxidation of the membrane compounds. In conclusion, the addition of α-tocopherol and ascorbic acid to the extender media, together with the antioxidant system of the spermatozoa improved sea bass sperm motility, which is one of the impairment parameters most affected by cryopreservation.     

Genome-wide MicroRNA Expression Profiles in COPD: Early Predictors for Cancer Development

Chronic obstructive pulmonary disease(COPD) significantly increases the risk of developing cancer. Biomarker studies frequently follow a case-control set-up in which patients diagnosed with a disease are compared to controls. Longitudinal cohort studies such as the COPD-centered German COPD and SYstemic consequences-COmorbidities NETwork(COSYCONET) study provide the patient and biomaterial base for discovering predictive molecular markers. We asked whether microRNA(miRNA) profiles in blood collected from COPD patients prior to a tumor diagnosis could support an early diagnosis of tumor development independent of the tumor type. From 2741 participants of COSYCONET diagnosed with COPD, we selected 534 individuals including 33 patients who developed cancer during the follow-up period of 54 months and 501 patients who did not develop cancer, but had similar age, gender and smoking history. Genome-wide miRNA profiles were generated and evaluated using machine learning techniques. For patients developing cancer we identified nine miRNAs with significantly decreased abundance(two-tailed unpaired t-test adjusted for multiple testing P 0.05), including members of the miR-320 family. The identified mi RNAs regulate different cancer-related pathways including the MAPK pathway(P = 2.3 x 10~(-5)). We also observed the impact of confounding factors on the generated miRNA profiles, underlining the value of our matched analysis. For selected miRNAs, qRT-PCR analysis was applied to validate the results. In conclusion, we identified several miRNAs in blood of COPD patients, which could serve as candidates for biomarkers to help identify COPD patients at risk of developing cancer.     

Second harvest–Is there sufficient stubble for biofuel production in Australia?

Identifying the location and amount of grain crop residues (stubble) in Australia is necessary for determining the viability of potential biofuel plant locations. We combined 22 years of crop statistics with harvest indices and land use to arrive at spatially explicit stubble productivity figures. Stubble quantities using different focal radii and from different seasons provide an insight into the feasibility of its use for bioenergy. We focus on areas where the stubble concentrations within a 50 km radius were at least 500 kt per year; the amount suggested for a viable lignocellolosic bioethanol facility. The outcome of this study has been to show, for the first time, where there are large amounts of stubble in Australia. Whether the supply of stubble is sufficiently constant over time and indeed available at a price that is economic for a biofuel plant must be subject to future work.