Evidence for Multiple Rhythmic Skills

Rhythms, or patterns in time, play a vital role in both speech and music. Proficiency in a number of rhythm skills has been linked to language ability, suggesting that certain rhythmic processes in music and language rely on overlapping resources. However, a lack of understanding about how rhythm skills relate to each other has impeded progress in understanding how language relies on rhythm processing. In particular, it is unknown whether all rhythm skills are linked together, forming a single broad rhythmic competence, or whether there are multiple dissociable rhythm skills. We hypothesized that beat tapping and rhythm memory/sequencing form two separate clusters of rhythm skills. This hypothesis was tested with a battery of two beat tapping and two rhythm memory tests. Here we show that tapping to a metronome and the ability to adjust to a changing tempo while tapping to a metronome are related skills. The ability to remember rhythms and to drum along to repeating rhythmic sequences are also related. However, we found no relationship between beat tapping skills and rhythm memory skills. Thus, beat tapping and rhythm memory are dissociable rhythmic aptitudes. This discovery may inform future research disambiguating how distinct rhythm competencies track with specific language functions.     

Activation of Mutant Enzyme Function In Vivo by Proteasome Inhibitors and Treatments that Induce Hsp70

Missense mutant proteins, such as those produced in individuals with genetic diseases, are often misfolded and subject to processing by intracellular quality control systems. Previously, we have shown using a yeast system that enzymatic function could be restored to I278T cystathionine β-synthase (CBS), a cause of homocystinuria, by treatments that affect the intracellular chaperone environment. Here, we extend these studies and show that it is possible to restore significant levels of enzyme activity to 17 of 18 (94%) disease causing missense mutations in human cystathionine β-synthase (CBS) expressed in Saccharomyces cerevisiae by exposure to ethanol, proteasome inhibitors, or deletion of the Hsp26 small heat shock protein. All three of these treatments induce Hsp70, which is necessary but not sufficient for rescue. In addition to CBS, these same treatments can rescue disease-causing mutations in human p53 and the methylene tetrahydrofolate reductase gene. These findings do not appear restricted to S. cerevisiae, as proteasome inhibitors can restore significant CBS enzymatic activity to CBS alleles expressed in fibroblasts derived from homocystinuric patients and in a mouse model for homocystinuria that expresses human I278T CBS. These findings suggest that proteasome inhibitors and other Hsp70 inducing agents may be useful in the treatment of a variety of genetic diseases caused by missense mutations.     

Evolution of the clinical presentation and outcomes after radical prostatectomy for patients with clinically localized prostate cancer--changing trends over a ten year period

We demonstrate the evolution of the clinical presentation and outcomes for patients with clinically localized prostate cancer (PC) treated with radical retropubic prostatectomy (RRP) at our department, emphasizing epidemiologic significance of changes during the 10-year period. We assessed the annual trends for changes in patients age, preoperative prostate specific antigen (PSA), preoperative versus postoperative stages and Gleason grades, organ confined status and surgical margin status. A total of 488 RRPs were performed from January 1996 to December 2005 with the annual frequency increased from 8 to 129 (1512.5%). Mean patient age increased from 61.5 to 66.12 years in 2005, with the percentage of men aged more than 70 years increased from 12.5 to 26.5%, respectively. The detection of PC based solely on pathological PSA levels (as indication for prostate biopsy) rose impressively from 25.5 to 70% and the rates of postoperative organ-confined disease also increased significantly from 25 to 74.7%. Mean preoperative PSA decreased from 16.7 to 9.89 ng/mL. On the contrary, there was an increase in percentage of patients with preoperative PSA values ranging from 4 to 10 ng/mL (from 20 to 65.4%). Positive surgical margin rate decreased from 49.4 to 25% and percent of patients receiving neoadjuvant therapy decreased from 78.5 to 5.4%. Proportion of patients who were undergraded decreased from 75.1 to 31.7%. The rates of understaging have remained relatively stable over the years. During the study period, PC was increasingly detected by prostate biopsy on the basis of a pathological PSA level only and shifted significantly to more organ-confined stages with more favourable outcomes for pathological variables due to a more accurate assessment of clinical stage prior to surgery, reduced use of neoadjuvant therapy and improved surgical technique. Our data also argue strongly that routine PSA testing should be expanded and not restricted.     

Discovery of 5-HT6 receptor ligands based on virtual HTS

Based on a pharmacophore alignment on a 5-HT(6) ligand applying 4SCan technology, a new lead series was identified and further structurally investigated. K(i)s down to 8 nM were achieved.     

Patterns of male reproductive success in a highly promiscuous whale species: the endangered North Atlantic right whale

Parentage analyses of baleen whales are rare, and although mating systems have been hypothesized for some species, little data on realized male reproductive success are available and the patterns of male reproductive success have remained elusive for most species. Here we combine over 20 years of photo-identification data with high-resolution genetic data for the majority of individual North Atlantic right whales to assess paternity in this endangered species. There was significant skew in male reproductive success compared to what would be expected if mating was random (P < 0.001). The difference was due to an excess of males assigned zero paternities, a deficiency of males assigned one paternity, and an excess of males assigned as fathers for multiple calves. The variance in male reproductive success was high relative to other aquatically mating marine mammals, but was low relative to mammals where the mating system is based on resource- and/or mate-defence polygyny. These results are consistent with previous data suggesting that the right whale mating system represents one of the most intense examples of sperm competition in mammals, but that sperm competition on its own does not allow for the same degree of polygyny as systems where males can control access to resources and/or mates. The age distribution of assigned fathers was significantly biased towards older males (P < 0.05), with males not obtaining their first paternity until approximately 15 years of age, which is almost twice the average age of first fertilization in females (8 years), suggesting that mate competition is preventing younger males from reproducing. The uneven distribution of paternities results in a lower effective population size in this species that already has one of the lowest reported levels of genetic diversity, which may further inhibit reproductive success through mate incompatibility of genetically similar individuals.     

Hydrogen sulfide mediates vasoactivity in an O2-dependent manner

Hydrogen sulfide (H(2)S) has recently been shown to have a signaling role in vascular cells. Similar to nitric oxide (NO), H(2)S is enzymatically produced by amino acid metabolism and can cause posttranslational modification of proteins, particularly at thiol residues. Molecular targets for H(2)S include ATP-sensitive K(+) channels, and H(2)S may interact with NO and heme proteins such as cyclooxygenase. It is well known that the reactions of NO in the vasculature are O(2) dependent, but this has not been addressed in most studies designed to elucidate the role of H(2)S in vascular function. This is important, since H(2)S reactions can be dramatically altered by the high concentrations of O(2) used in cell culture and organ bath experiments. To test the hypothesis that the effects of H(2)S on the vasculature are O(2) dependent, we have measured real-time levels of H(2)S and O(2) in respirometry and vessel tension experiments, as well as the associated vascular responses. A novel polarographic H(2)S sensor developed in our laboratory was used to measure H(2)S levels. Here we report that, in rat aorta, H(2)S concentrations that mediate rapid contraction at high O(2) levels cause rapid relaxation at lower physiological O(2) levels. At high O(2), the vasoconstrictive effect of H(2)S suggests that it may not be H(2)S per se but, rather, a putative vasoactive oxidation product that mediates constriction. These data are interpreted in terms of the potential for H(2)S to modulate vascular tone in vivo.