Screening of a Custom-Designed Acid Fragment Library Identifies 1-Phenylpyrroles and 1-Phenylpyrrolidines as Inhibitors of Notum Carboxylesterase Activity

The Wnt family of proteins are secreted signaling proteins that play key roles in regulating cellular functions. Recently, carboxylesterase Notum was shown to act as a negative regulator of Wnt signaling by mediating the removal of an essential palmitoleate. Here we disclose two new chemical scaffolds that inhibit Notum enzymatic activity. Our approach was to create a fragment library of 250 acids for screening against Notum in a biochemical assay followed by structure determination by X-ray crystallography. Twenty fragments were identified as hits for Notum inhibition, and 14 of these fragments were shown to bind in the palmitoleate pocket of Notum. Optimization of 1-phenylpyrrole 20, guided by structure-based drug design, identified 20z as the most potent compound from this series. Similarly, the optimization of 1-phenylpyrrolidine 8 gave acid 26. This work demonstrates that inhibition of Notum activity can be achieved by small, drug-like molecules possessing favorable in vitro ADME profiles

Alteration of inhibitory circuits in the somatosensory cortex of Ts65Dn mice, a model for Down's syndrome

Down's syndrome (DS), with an incidence of one in 800 live births, is the most common genetic disorder associated with mental retardation. This trisomy on chromosome 21 induces a variable phenotype in which the only common feature is the presence of mental retardation. The neural mechanisms underlying mental retardation might include defects in the formation of neuronal networks and neural plasticity. DS patients have alterations in the morphology, the density and the distribution of dendritic spines in the pyramidal neurons of the cortex. Our hypothesis is that the deficits in dendritic arborization observed in the principal neurons of DS patients and Ts65Dn mice (a model for DS that mimics most of the structural alterations observed in humans) may be mediated to some extent by changes in their inhibitory inputs. Different types of interneurons control different types of inhibition. Therefore, to understand well the changes in inhibition in DS, it is necessary to study the different types of interneurons separately. We have studied the expression of synaptophysin, Glutamic acid decarboxylase-67 (GAD-67) and calcium-binding protein-expressing cells in the primary somatosensory cortex of 4¿5 month old Ts65Dn mice. We have observed an increment of GAD67 immunoreactivity that is related mainly to an increment of calretinin-immunoreactive cells and among them the ones with bipolar morphology. Since there is a propensity for epilepsy in DS patients, this increase in interneurons might reflect an attempt by the system to block overexcitation rather than an increment in total inhibition and could explain the deficit in interneurons and principal cells observed in elderly DS patients

Revisiting the pH-gated conformational switch on the activities of HisKA-family histidine kinases

Histidine is a versatile residue playing key roles in enzyme catalysis thanks to the chemistry of its imidazole group that can serve as nucleophile, general acid or base depending on its protonation state. In bacteria, signal transduction relies on two-component systems (TCS) which comprise a sensor histidine kinase (HK) containing a phosphorylatable catalytic His with phosphotransfer and phosphatase activities over an effector response regulator. Recently, a pH-gated model has been postulated to regulate the phosphatase activity of HisKA HKs based on the pH-dependent rotamer switch of the phosphorylatable His. Here, we have revisited this model from a structural and functional perspective on HK853-RR468 and EnvZ-OmpR TCS, the prototypical HisKA HKs. We have found that the rotamer of His is not influenced by the environmental pH, ruling out a pH-gated model and confirming that the chemistry of the His is responsible for the decrease in the phosphatase activity at acidic pH

Mechanisms of initiation and reversal of drug-seeking behavior induced by prenatal exposure to glucocorticoids

We would like to thank the members of the Neuroscience Research Domain at ICVS for all the helpful discussions and suggestions. We are especially thankful to the animal facility caretakers, and to Drs Sara Silva, António Melo and Ana Paula Silva and Dieter Fischer for their helpStress and exposure to glucocorticoids (GC) during early life render individuals vulnerable to brain disorders by inducing structural and chemical alterations in specific neural substrates. Here we show that adult rats that had been exposed to in utero GCs (iuGC) display increased preference for opiates and ethanol, and are more responsive to the psychostimulatory actions of morphine. These animals presented prominent changes in the nucleus accumbens (NAcc), a key component of the mesolimbic reward circuitry; specifically, cell numbers and dopamine (DA) levels were significantly reduced, whereas DA receptor 2 (Drd2) mRNA expression levels were markedly upregulated in the NAcc. Interestingly, repeated morphine exposure significantly downregulated Drd2 expression in iuGC-exposed animals, in parallel with increased DNA methylation of the Drd2 gene. Administration of a therapeutic dose of L-dopa reverted the hypodopaminergic state in the NAcc of iuGC animals, normalized Drd2 expression and prevented morphine-induced hypermethylation of the Drd2 promoter. In addition, L-dopa treatment promoted dendritic and synaptic plasticity in the NAcc and, importantly, reversed drug-seeking behavior. These results reveal a new mechanism through which drug-seeking behaviors may emerge and suggest that a brief and simple pharmacological intervention can restrain these behaviors in vulnerable individuals.This work was supported by the Institute for the Study of Affective Neuroscience (ISAN). AJR, BC and MC were supported by Fundação para a Ciência e Tecnologia (FCT) fellowship

Out-of-pocket expenditures for pharmaceuticals: lessons from the Austrian household budget survey

BACKGROUND: Paying pharmaceuticals out-of-pocket is an important source of financing pharmaceutical consumption. Only limited empirical knowledge is available on the determinants of these expenditures. OBJECTIVES: In this paper we analyze which characteristics of private households influence out-of-pocket pharmaceutical expenditure (OOPPE) in Austria. DESIGN & METHODS: We use cross-sectional information on OOPPE and on household characteristics provided by the Austrian household budget survey 2009/10. We split pharmaceutical expenditures into the two components prescription fees and over-the-counter (OTC) expenditures. To adjust for the specific characteristics of the data we compare different econometric approaches: two-part model, hurdle model, generalized linear model, zero-inflated negative binomial regression model. FINDINGS: The finally selected econometric approaches give a quite consistent picture. The probability of expenditures of both types is strongly influenced by the household structure. It increases with age, doctoral visits and the presence of a female householder. The education level and income only increase the probability of OTC-pharmaceuticals. The level of OTC-expenditures remains widely unexplained while the household structure and age influences the expenditures for prescription fees. Insurance characteristics of private households either private or public play a minor role in explaining the expenditure levels in all specifications. This refers to a homogenous and comprehensive provision of pharmaceuticals in the public part of the Austrian health care system. CONCLUSIONS: The paper gives useful insights into the determinants of pharmaceutical expenditures of private households and supplements the previous research which focuses on the individual level

International consensus on natural orifice specimen extraction surgery (NOSES) for colorectal cancer

In recent years, natural orifice specimen extraction surgery (NOSES) in the treatment of colorectal cancer has attracted widespread attention. The potential benefits of NOSES including reduction in postoperative pain and wound complications, less use of postoperative analgesic, faster recovery of bowel function, shorter length of hospital stay, better cosmetic and psychological effect have been described in colorectal surgery. Despite significant decrease in surgical trauma of NOSES have been observed, the potential pitfalls of this technique have been demonstrated. Particularly, several issues including bacteriological concerns, oncological outcomes and patient selection are raised with this new technique. Therefore, it is urgent and necessary to reach a consensus as an industry guideline to standardize the implementation of NOSES in colorectal surgery. After three rounds of discussion by all members of the International Alliance of NOSES, the consensus is finally completed, which is also of great significance to the long-term progress of NOSES worldwide.info:eu-repo/semantics/publishedVersio

Evidence for the h_b(1P) meson in the decay Upsilon(3S) --> pi0 h_b(1P)

Using a sample of 122 million Upsilon(3S) events recorded with the BaBar detector at the PEP-II asymmetric-energy e+e- collider at SLAC, we search for the $h_b(1P)$ spin-singlet partner of the P-wave chi_{bJ}(1P) states in the sequential decay Upsilon(3S) --> pi0 h_b(1P), h_b(1P) --> gamma eta_b(1S). We observe an excess of events above background in the distribution of the recoil mass against the pi0 at mass 9902 +/- 4(stat.) +/- 2(syst.) MeV/c^2. The width of the observed signal is consistent with experimental resolution, and its significance is 3.1sigma, including systematic uncertainties. We obtain the value (4.3 +/- 1.1(stat.) +/- 0.9(syst.)) x 10^{-4} for the product branching fraction BF(Upsilon(3S)-->pi0 h_b) x BF(h_b-->gamma eta_b).Comment: 8 pages, 4 postscript figures, submitted to Phys. Rev. D (Rapid Communications