1,280 research outputs found

    The effects of species ortholog and SNP variation on receptors for free fatty acids

    Get PDF
    Although it is widely assumed that species orthologs of hormone responsive G protein-coupled receptors will be activated by the same endogenously produced ligand(s), variation in potency, particularly in cases where more than one receptor responds to the same hormone, can result in challenges in defining the contribution of individual receptors in different species. This can create considerably greater issues when using synthetic chemical ligands and, in some cases, may result in a complete lack of efficacy of such a ligand when used in animal models of pathophysiology. In man, the concept that distinct responses of individuals to medicines may reflect differences in the ability of such drugs to bind to or activate single nucleotide polymorphism variants of receptors is more established as a concept but, in many cases, clear links between such variants that are associated with disease phenotypes and substantial differences in receptor ligand pharmacology have been more difficult to obtain. Herein, we consider each of these issues for the group of receptors, FFA1-FFA4, defined to be activated by free fatty acids of varying chain length which, based on their production by one tissue or location and action in distinct locations, have been suggested to possess characteristics of ‘hormones’

    Do female association preferences predict the likelihood of reproduction?

    Get PDF
    Sexual selection acting on male traits through female mate choice is commonly inferred from female association preferences in dichotomous mate choice experiments. However, there are surprisingly few empirical demonstrations that such association preferences predict the likelihood of females reproducing with a particular male. This information is essential to confirm association preferences as good predictors of mate choice. We used green swordtails (<i>Xiphophorus helleri</i>) to test whether association preferences predict the likelihood of a female reproducing with a male. Females were tested for a preference for long- or short-sworded males in a standard dichotomous choice experiment and then allowed free access to either their preferred or non-preferred male. If females subsequently failed to produce fry, they were provided a second unfamiliar male with similar sword length to the first male. Females were more likely to reproduce with preferred than non-preferred males, but for those that reproduced, neither the status (preferred/non-preferred) nor the sword length (long/short) of the male had an effect on brood size or relative investment in growth by the female. There was no overall preference based on sword length in this study, but male sword length did affect likelihood of reproduction, with females more likely to reproduce with long- than short-sworded males (independent of preference for such males in earlier choice tests). These results suggest that female association preferences are good indicators of female mate choice but that ornament characteristics of the male are also important

    Interpersonal Dysfunction in Depressed Women: Impairments Independent of Depressive Symptoms

    Get PDF
    Background: The study explored the generality of interpersonal impairments in depressed women and examined the extent of their independence of current depressive episodes or symptoms. Methods: 812 community women who were formerly depressed, currently depressed, or never depressed were compared on a variety of indices of interpersonal behavior and beliefs. Information was also obtained from their spouses, adolescent children, and raters. Current depressive mood and sociodemographic factors that might affect social functioning were controlled. Results: Consistent with the hypotheses that interpersonal difficulties are not just consequences of depressive symptoms, formerly but not currently depressed women were significantly more impaired than never-depressed women on nearly all measures. They were less likely to be stably married, had poorer marital satisfaction, reported more spouse coercion and physical injury, had more problematic relationships with their child, friends, and extended family, reported more stressful life events with interpersonal and conflict content, and were more insecure in their beliefs about other people. Their spouses and boyfriends also reported more problems, and were themselves more likely to have diagnosable disorders. However, the groups did not differ in their children's perceptions of maternal warmth or hostility. Limitations: The cross-sectional design precluded conclusions about the causal direction of the relationship between interpersonal impairment and depressive disorder. Since clinical depression is more often than not followed by subthreshold symptoms that are not captured by standard diagnostic instruments, such symptoms are not easily discernable from preceding or co-existing interpersonal problems. Only women were studied. Conclusions: Interpersonal impairment is a stable feature of depression, a significant challenge to treatment, and may reflect underlying vulnerability to the onset, and recurrence, of depressive experiences

    From Re-Emergence to Hyperendemicity: The Natural History of the Dengue Epidemic in Brazil

    Get PDF
    The spread of dengue virus is a major public health problem. Though the burden of dengue has historically been concentrated in Southeast Asian countries, Brazil has become the country that reports the largest number of cases in the world. While prior to 2007 the disease affected mostly adults, during the 2007 epidemic the number of dengue hemorrhagic fever cases more than doubled, and over 53% of cases were in children under 15 years of age. In this paper, we propose that the conditions for the shift were being set gradually since the re-introduction of dengue in 1986 and that they represent the transition from re-emergence to hyperendemicity. Using data from an age stratified seroprevalence study conducted in Recife, we estimated the force of infection (a measure of transmission intensity) between 1986–2006 and used these estimates to simulate the accumulation of immunity since the re-emergence. As the length of time that dengue has circulated increases, adults have a lower probability of remaining susceptible to primary or secondary infection and thus, cases become on average younger. If in fact the shift represents the transition from re-emergence to hyperendemicity, similar shifts are likely to be observed in the rest of Brazil, the American continent and other regions where transmission emerges

    Clinical report of cervical arthroplasty in management of spondylotic myelopathy in Chinese

    Get PDF
    OBJECTIVES: To investigate clinical effects and manual operational point of Bryan cervical disc prosthesis in Chinese, to observe the stability and range of movement (ROM) post-operatively. METHODS AND MATERIALS: From 2003,12 to 2005,12, Bryan disc prosthesis replacement applied in 83 cases (102 levels) of cervical spondylotic myelopathy (CSM) after anterior decompression in our hospital. Clinical (JOA grade and Odom's scale) and radiological (X-ray of flexion, extension; left and right bending position) follow-up was performed. Systemic radiographic study about stability and ROM of replaced level post operationally were measured. CT or MRI scans were applied in all cases to evaluate the signs of the prosthesis deflexion and hetero-ossification in the replaced levels. RESULTS: At least 12 months follow-up were done in 65/83 of these paients. All of 83 patients were improved according to Odsm's scale. JOA score increased from average 8.7 to 15.5. There was no prosthesis subsidence. Replaced segment achieved stability and restored partial of normal ROM 4.73°(3.7°–5.9°) early postoperation and 8.12°(5.8°–13.6°) more than 12 months postoperation in flex and extension position. No obvious loss of lordosis was found. CT or MRI follow-up shows position deflexion of the prosthesis metal endplates (<1.5 mm) in 14/77 levels and (1.5~3 mm) in 4/77. heter-ossification was found in the replaced levels only in 2 cases. CONCLUSION: Byran cervical disc prosthesis restored motion to the level of the intact segment in flexion-extension and lateral bending in post-operative images. At the same time, it can achieve good anterior decompression treatment effect and immediate stability in replaced 1 or 2 levels, and which is a new choice for the treatment of CSM

    The Bone-Protective Effect of Genistein in the Animal Model of Bilateral Ovariectomy: Roles of Phytoestrogens and PTH/PTHR1 Against Post-Menopausal Osteoporosis

    Get PDF
    Genistein, a major phytoestrogen of soy, is considered a potential drug for the prevention and treatment of post-menopausal osteoporosis. Mounting evidence suggested a positive correlation between genistein consumption and bone health both in vivo and in vitro. Earlier studies have revealed that genistein acted as a natural estrogen analogue which activated estrogen receptor and exerted anti-osteoporotic effect. However, it remains unclear whether PTH, the most crucial hormone that regulates mineral homeostasis, participates in the process of genistein-mediated bone protection. In the present study, we compared the therapeutic effects between genistein and nilestriol and investigated whether PTH and its specific receptor PTHR1 altered in response to genistein-containing diet in the animal model of ovariectomy. Our results showed that genistein administration significantly improved femoral mechanical properties and alleviates femoral turnover. Genistein at all doses (4.5 mg/kg, 9.0 mg/kg and 18.0 mg/kg per day, respectively) exerted improved bending strength and b-ALP limiting effects than nilestriol in the present study. However, genistein administration did not exert superior effects on bone protection than nilestriol. We also observed circulating PTH restoration in ovariectomized rats receiving genistein at the dose of 18 mg/kg per day. Meanwhile, PTHR1 abnormalities were attenuated in the presence of genistein as confirmed by RT-PCR, Western blot and immunohistochemistry. These findings strongly support the idea that besides serving as an estrogen, genistein could interact with PTH/PTHR1, causing a superior mineral restoring effect than nilestriol on certain circumstance. In conclusion, our study reported for the first time that the anti-osteoporotic effect of genistein is partly PTH/PTHR1-dependent. Genistein might be a potential option in the prevention and treatment of post-menopausal osteoporosis with good tolerance, more clinical benefits and few undesirable side effects

    Precision Measurement of the Mass of the h_c(1P1) State of Charmonium

    Full text link
    A precision measurement of the mass of the h_c(1P1) state of charmonium has been made using a sample of 24.5 million psi(2S) events produced in e+e- annihilation at CESR. The reaction used was psi(2S) -> pi0 h_c, pi0 -> gamma gamma, h_c -> gamma eta_c, and the reaction products were detected in the CLEO-c detector. Data have been analyzed both for the inclusive reaction and for the exclusive reactions in which eta_c decays are reconstructed in fifteen hadronic decay channels. Consistent results are obtained in the two analyses. The averaged results of the present measurements are M(h_c)=3525.28+-0.19 (stat)+-0.12(syst) MeV, and B(psi(2S) -> pi0 h_c)xB(h_c -> gamma eta_c)= (4.19+-0.32+-0.45)x10^-4. Using the 3PJ centroid mass, Delta M_hf(1P)= - M(h_c) = +0.02+-0.19+-0.13 MeV.Comment: 9 pages, available through http://www.lns.cornell.edu/public/CLNS/, submitted to PR

    Precision Measurement of B(D+ -> mu+ nu) and the Pseudoscalar Decay Constant fD+

    Full text link
    We measure the branching ratio of the purely leptonic decay of the D+ meson with unprecedented precision as B(D+ -> mu+ nu) = (3.82 +/- 0.32 +/- 0.09)x10^(-4), using 818/pb of data taken on the psi(3770) resonance with the CLEO-c detector at the CESR collider. We use this determination to derive a value for the pseudoscalar decay constant fD+, combining with measurements of the D+ lifetime and assuming |Vcd| = |Vus|. We find fD+ = (205.8 +/- 8.5 +/- 2.5) MeV. The decay rate asymmetry [B(D+ -> mu+ nu)-B(D- -> mu- nu)]/[B(D+ -> mu+ nu)+B(D- -> mu- nu)] = 0.08 +/- 0.08, consistent with no CP violation. We also set 90% confidence level upper limits on B(D+ -> tau+ nu) < 1.2x10^(-3) and B(D+ -> e+ nu) < 8.8x10^(-6).Comment: 24 pages, 11 figures and 6 tables, v2 replaced some figure vertical axis scales, v3 corrections from PRD revie

    Determination of the D0 -> K+pi- Relative Strong Phase Using Quantum-Correlated Measurements in e+e- -> D0 D0bar at CLEO

    Full text link
    We exploit the quantum coherence between pair-produced D0 and D0bar in psi(3770) decays to study charm mixing, which is characterized by the parameters x and y, and to make a first determination of the relative strong phase \delta between doubly Cabibbo-suppressed D0 -> K+pi- and Cabibbo-favored D0bar -> K+pi-. We analyze a sample of 1.0 million D0D0bar pairs from 281 pb^-1 of e+e- collision data collected with the CLEO-c detector at E_cm = 3.77 GeV. By combining CLEO-c measurements with branching fraction input and time-integrated measurements of R_M = (x^2+y^2)/2 and R_{WS} = Gamma(D0 -> K+pi-)/Gamma(D0bar -> K+pi-) from other experiments, we find \cos\delta = 1.03 +0.31-0.17 +- 0.06, where the uncertainties are statistical and systematic, respectively. In addition, by further including external measurements of charm mixing parameters, we obtain an alternate measurement of \cos\delta = 1.10 +- 0.35 +- 0.07, as well as x\sin\delta = (4.4 +2.7-1.8 +- 2.9) x 10^-3 and \delta = 22 +11-12 +9-11 degrees.Comment: 37 pages, also available through http://www.lns.cornell.edu/public/CLNS/2007/. Incorporated referee's comment
    • …
    corecore