Comparing coordination uranyl(vi) complexes with 2-(1H-imidazo[4,5-b]phenazin-2-yl)phenol and derivatives.

Four derivatives of 2-(1H-imidazo[4,5-b]phenazin-2-yl)phenol have been synthesized and characterized structurally using X-ray crystallography. Coordination complexes with uranyl (UO22+) and copper (Cu2+) were prepared and absorption/emission spectra detailed. We observed increased fluorescence upon uranyl binding, in stark contrast to rapid quenching observed with the addition of copper. These phenomena have been further examined by DFT computational methods.

Contrasting patterns of X-chromosome divergence underlie multiple sex-ratio polymorphisms in stalk-eyed flies.

Sex-linked segregation distorters cause offspring sex ratios to differ from equality. Theory predicts that such selfish alleles may either go to fixation and cause extinction, reach a stable polymorphism or initiate an evolutionary arms race with genetic modifiers. The extent to which a sex ratio distorter follows any of these trajectories in nature is poorly known. Here, we used X-linked sequence and simple tandem repeat data for three sympatric species of stalk-eyed flies (Teleopsis whitei and two cryptic species of T. dalmanni) to infer the evolution of distorting X chromosomes. By screening large numbers of field and recently laboratory-bred flies, we found no evidence of males with strongly female-biased sex ratio phenotypes (SR) in one species but high frequencies of SR males in the other two species. In the two species with SR males, we find contrasting patterns of X-chromosome evolution. T. dalmanni-1 shows chromosome-wide differences between sex-ratio (XSR ) and standard (XST ) X chromosomes consistent with a relatively old sex-ratio haplotype based on evidence including genetic divergence, an inversion polymorphism and reduced recombination among XSR chromosomes relative to XST chromosomes. In contrast, we found no evidence of genetic divergence on the X between males with female-biased and nonbiased sex ratios in T. whitei. Taken with previous studies that found evidence of genetic suppression of sex ratio distortion in this clade, our results illustrate that sex ratio modification in these flies is undergoing recurrent evolution with diverse genomic consequences.

[Adenoviral Vectors in Gene Therapy]. / Adenovírusové vektory v génovej terapii.

This review is focused on gene therapy, especially adenovirus vectors and their relationship with the immune system response. Adenovirus vectors belong to the most used gene delivery vehicles in gene therapy, study of gene expression or immunotherapy. One of the most important questions concerning their use is their influence on organism in vivo. Study of immunomodulating properties of the adenovirus vectors opens a way for further manipulation and their more effective practical use.

The locus of sexual selection: moving sexual selection studies into the post-genomics era.

Sexual selection drives fundamental evolutionary processes such as trait elaboration and speciation. Despite this importance, there are surprisingly few examples of genes unequivocally responsible for variation in sexually selected phenotypes. This lack of information inhibits our ability to predict phenotypic change due to universal behaviours, such as fighting over mates and mate choice. Here, we discuss reasons for this apparent gap and provide recommendations for how it can be overcome by adopting contemporary genomic methods, exploiting underutilized taxa that may be ideal for detecting the effects of sexual selection and adopting appropriate experimental paradigms. Identifying genes that determine variation in sexually selected traits has the potential to improve theoretical models and reveal whether the genetic changes underlying phenotypic novelty utilize common or unique molecular mechanisms. Such a genomic approach to sexual selection will help answer questions in the evolution of sexually selected phenotypes that were first asked by Darwin and can furthermore serve as a model for the application of genomics in all areas of evolutionary biology.

[Ananlysis of phosphoproteins and signalling pathways by quantitative proteomics]. / Analýza fosfoproteínov a signálnych dráh kvantitatívno proteomickými metódami.

Protein phosphorylation is a key regulator in cellular signaling pathways. It is involved in most cellular events in which interplay between phosphatases and kinases strictly controls bio-logical processes, such as differentiation, proliferation and apoptosis. Altered or defective signaling pathways often result in various diseases, emphasizing the importance of studying the phosphoproteome. The abundance of phosphoproteins in the proteome is often very low, which requires specific and highly sensitive approaches. By using quantitative proteomics methods, we are able to analyze changes in abundance of proteins and their posttranslational modifications and then changes in signaling pathways. In this review, we describe quantitative proteomics methods, which could be used for study of phosphoproteins and their connection in signaling pathways.

Characterization of the heterozygous glucokinase knockout mouse as a translational disease model for glucose control in type 2 diabetes.

BACKGROUND AND PURPOSE: The global heterozygous glucokinase (GK) knockout (gk(wt/del)) male mouse, fed on a high-fat (60% by energy) diet, has provided a robust and reproducible model of hyperglycaemia. This model could be highly relevant to some facets of human type 2 diabetes (T2D). We aimed to investigate the ability of standard therapeutic agents to lower blood glucose at translational doses, and to explore the glucose-lowering potential of novel glucokinase activators (GKAs) in this model. EXPERIMENTAL APPROACH: We measured the ability of insulin, metformin, glipizide, exendin-4 and sitagliptin, after acute or repeat dose administration, to lower free-feeding glucose levels in gk(wt/del) mice. Further, we measured the ability of novel GKAs, GKA23, GKA71 and AZD6370 to control glucose either alone or in combination with some standard agents. KEY RESULTS: A single dose of insulin (1 unit·kg(-1)), metformin (150, 300 mg·kg(-1)), glipizide (0.1, 0.3 mg·kg(-1)), exendin-4 (2, 20 µg·kg(-1)) and GKAs reduced free-feeding glucose levels. Sitagliptin (10 mg·kg(-1)), metformin (300 mg·kg(-1)) and AZD6370 (30, 400 mg·kg(-1)) reduced glucose excursions on repeat dosing. At a supra-therapeutic dose (400 mg·kg(-1)), AZD6370 also lowered basal levels of glucose without inducing hypoglycaemia. CONCLUSION AND IMPLICATIONS: Standard glucose-lowering therapeutic agents demonstrated significant acute glucose lowering in male gk(wt/del) mice at doses corresponding to therapeutic free drug levels in man, suggesting the potential of these mice as a translatable model of human T2D. Novel GKAs also lowered glucose in this mouse model.

Chronic glucokinase activator treatment at clinically translatable exposures gives durable glucose lowering in two animal models of type 2 diabetes.

BACKGROUND AND PURPOSE: Pharmacological activation of glucokinase (GK) lowers blood glucose in animal models and humans, confirming proof of concept for this mechanism. However, recent clinical evidence from chronic studies suggests that the glucose-lowering effects mediated by glucokinase activators (GKAs) are not maintained in patients with type 2 diabetes (T2D). Existing preclinical data with GKAs do not explain this loss of sustained glucose-lowering efficacy in patients. Here, we have assessed the effects of chronic (up to 11 months) treatment with two different GKAs in two models of T2D. EXPERIMENTAL APPROACH: Two validated animal models of T2D, insulin-resistant obese Zucker rats and hyperglycaemic gk(wt/del) mice, were treated with two different GKAs for 1 or 11 months respectively at exposures that translate to clinical exposures in humans. Blood glucose, cholesterol, triglycerides and insulin were measured. GKA pharmacokinetics were also determined. KEY RESULTS: Treatment with either GKA provided sustained lowering of blood glucose for up to 1 month in the Zucker rat and up to 11 months in hyperglycaemic gk(wt/del) mice, with maintained compound exposures. This efficacy was achieved without increases in plasma or hepatic triglycerides, accumulation of hepatic glycogen or impairment of glucose-stimulated insulin secretion. CONCLUSIONS AND IMPLICATIONS: Chronic treatment with two GKAs in two animal models of diabetes provided sustained lowering of blood glucose, in marked contrast to clinical findings. Therefore, either these animal models of T2D are not good predictors of responses in human T2D or we need a better understanding of the consequences of GK activation in humans.

Proneural genes in neocortical development.

Neurons, astrocytes and oligodendrocytes arise from CNS progenitor cells at defined times and locations during development, with transcription factors serving as key determinants of these different neural cell fates. An emerging theme is that the transcription factors that specify CNS cell fates function in a context-dependent manner, regulated by post-translational modifications and epigenetic alterations that partition the genome (and hence target genes) into active or silent domains. Here we profile the critical roles of the proneural genes, which encode basic-helix-loop-helix (bHLH) transcription factors, in specifying neural cell identities in the developing neocortex. In particular, we focus on the proneural genes Neurogenin 1 (Neurog1), Neurog2 and Achaete scute-like 1 (Ascl1), which are each expressed in a distinct fashion in the progenitor cell pools that give rise to all of the neuronal and glial cell types of the mature neocortex. Notably, while the basic functions of these proneural genes have been elucidated, it is becoming increasingly evident that tight regulatory controls dictate when, where and how they function. Current efforts to better understand how proneural gene function is regulated will not only improve our understanding of neocortical development, but are also critical to the future development of regenerative therapies for the treatment of neuronal degeneration or disease.

First measurement of the form factors in the decays D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e).

The beauty to up quark coupling constant |V(ub)| can be extracted from B → ρ e+ ν(e) combined with the form factors for D → K* e+ ν(e) and B → V ℓ+ ℓ- and D → ρ e+ ν(e). Using the entire CLEO-c ψ(3770) → DD event sample, corresponding to an integrated luminosity of 818 pb(-1) and approximately 5.4×10(6) DD events, we measure the form factors for the decays D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e) for the first time and the branching fractions with improved precision. A four-dimensional unbinned maximum likelihood fit determines the form factor ratios to be V(0)/A1(0)=1.48±0.15±0.05 and A2(0)/A1(0)=0.83±0.11±0.04. Assuming Cabibbo-Kobayashi-Maskawa unitarity, the known D meson lifetimes, and our measured branching fractions we obtain the form factor normalizations A1(0), A2(0), and V(0). We also present a measurement of the branching fraction for D+ → ω e+ ν(e) with improved precision.

Effects of ornamentation and phylogeny on the evolution of wing shape in stalk-eyed flies (Diopsidae).

Exaggerated male ornaments are predicted to be costly to their bearers, but these negative effects may be offset by the correlated evolution of compensatory traits. However, when locomotor systems, such as wings in flying species, evolve to decrease such costs, it remains unclear whether functional changes across related species are achieved via the same morphological route or via alternate changes that have similar function. We conducted a comparative analysis of wing shape in relation to eye-stalk elongation across 24 species of stalk-eyed flies, using geometric morphometrics to determine how species with increased eye span, a sexually selected trait, have modified wing morphology as a compensatory mechanism. Using traditional and phylogenetically informed multivariate analyses of shape in combination with phenotypic trajectory analysis, we found a strong phylogenetic signal in wing shape. However, dimorphic species possessed shifted wing veins with the result of lengthening and narrowing wings compared to monomorphic species. Dimorphic species also had changes that seem unrelated to wing size, but instead may govern wing flexion. Nevertheless, the lack of a uniform, compensatory pattern suggests that stalk-eyed flies used alternative modifications in wing structure to increase wing area and aspect ratio, thus taking divergent morphological routes to compensate for exaggerated eye stalks.

Treatment for older men with fractures.

UNLABELLED: Less than 10% of men receive osteoporosis treatment, even after a fracture. A study of 17,683 men revealed that older men, those with spinal fractures, and those taking steroids or antidepressants are more likely to receive treatment after a fracture. Seeing a primary care physician also increases osteoporosis treatment rates. INTRODUCTION: In 2000, the FDA approved bisphosphonates for the treatment of osteoporosis in men. The purpose of this study is to estimate the frequency of bisphosphonate therapy within 12 months following a fracture and describe patient/physician factors associated with treatment. METHODS: Health insurance claims for 17,683 men ≥ 65 years of age, who had a claim for an incident fracture from 2000 to 2005, were followed for at least 6 months post-fracture for the initiation of treatment with a bisphosphonate. Patient characteristics, diagnostic procedures, therapies, co-morbidities, and provider characteristics were compared for men who received treatment with those who did not. RESULTS: Eight percent of men (n = 1,434) received bisphosphonate therapy. Overall treatment increased from 7% in 2001 to 9% in 2005 (p < 0.001). Treatment for hip fractures remained at 7% (p = 0.747). Treatment increased with age: 6% in men aged 65-69 compared to 11.6% in men aged 85-89 (p < 0.001). Factors associated with treatment included: diagnosis of osteoporosis (OR = 8.8; 95% CI, 7.7, 10.4), glucocorticoid therapy (OR = 3.2; 95% CI, 2.4, 4.3), bone mineral density measurement (OR = 3.4; 95% CI, 2.9, 4.0), and antidepressant therapy with tricyclics (OR = 2.0; 95% CI, 1.2, 3.5) or selective serotonin reuptake inhibitors (OR = 1.7; 95% CI, 1.3, 2.4). Men with vertebral fractures (OR = 2.2; 95% CI, 1.8, 2.6) and men seen by primary physicians (OR = 2.6; 95% CI, 2.3, 3.1) were more likely to receive treatment. CONCLUSIONS: Less than 10% of men received bisphosphonate therapy following a low-impact fracture. Men with a primary physician were more likely to receive bisphosphonate therapy; however, <25% of men were seen by a primary physician.

Observation of the h(c)(1P) Using e+ e- collisions above the DD threshold.

Using 586 pb(-1) of e+ e- collision data at E(c.m.) = 4170 MeV, produced at the Cornell Electron Storage Ring collider and collected with the CLEO-c detector, we observe the process e+ e- → π+ π- h(c)(1P). We measure its cross section to be 15.6±2.3±1.9±3.0 pb, where the third error is due to the external uncertainty on the branching fraction of ψ(2S) → π0 h(c)(1P), which we use for normalization. We also find evidence for e+ e- → ηh(c)(1P) at 4170 MeV at the 3σ level and see hints of a rise in the e+ e- → π+ π- h(c)(1P) cross section at 4260 MeV.

Residues within the transmembrane domain of the glucagon-like peptide-1 receptor involved in ligand binding and receptor activation: modelling the ligand-bound receptor.

The C-terminal regions of glucagon-like peptide-1 (GLP-1) bind to the N terminus of the GLP-1 receptor (GLP-1R), facilitating interaction of the ligand N terminus with the receptor transmembrane domain. In contrast, the agonist exendin-4 relies less on the transmembrane domain, and truncated antagonist analogs (e.g. exendin 9-39) may interact solely with the receptor N terminus. Here we used mutagenesis to explore the role of residues highly conserved in the predicted transmembrane helices of mammalian GLP-1Rs and conserved in family B G protein coupled receptors in ligand binding and GLP-1R activation. By iteration using information from the mutagenesis, along with the available crystal structure of the receptor N terminus and a model of the active opsin transmembrane domain, we developed a structural receptor model with GLP-1 bound and used this to better understand consequences of mutations. Mutation at Y152 [transmembrane helix (TM) 1], R190 (TM2), Y235 (TM3), H363 (TM6), and E364 (TM6) produced similar reductions in affinity for GLP-1 and exendin 9-39. In contrast, other mutations either preferentially [K197 (TM2), Q234 (TM3), and W284 (extracellular loop 2)] or solely [D198 (TM2) and R310 (TM5)] reduced GLP-1 affinity. Reduced agonist affinity was always associated with reduced potency. However, reductions in potency exceeded reductions in agonist affinity for K197A, W284A, and R310A, while H363A was uncoupled from cAMP generation, highlighting critical roles of these residues in translating binding to activation. Data show important roles in ligand binding and receptor activation of conserved residues within the transmembrane domain of the GLP-1R. The receptor structural model provides insight into the roles of these residues.

Safe eye surgery: non-technical aspects.

The traditional training of surgeons focused exclusively on developing knowledge, clinical expertise, and technical (surgical) skills. However, analyses of the reasons for adverse events in surgery have revealed that many underlying causes originate from behavioural or non-technical aspects of performance (eg, poor communication among members of the surgical team) rather than from a lack of surgical (ie, technical) skills. Therefore, technical skills appear to be necessary but not sufficient to ensure patient safety. Paying attention to non-technical skills, such as team working, leadership, situation awareness, decision making, and communication, will increase the likelihood of maintaining high levels of error-free performance. Identification and training of non-technical skills has been developed for high-risk careers, such as civil aviation and nuclear power. Only recently, training in non-technical skills has been adopted by the surgical world and anaesthetists. Non-technical skills need to be tailored to the environment where they are used, and eye surgery has some substantial differences compared with other surgical areas, for example, high volume of surgery, use of local anaesthetics, and very sophisticated equipment. This review highlights the need for identification of the non-technical skills relevant to eye surgeons and promotion of their use in the training of eye surgeons.

Role of the signal peptide in the synthesis and processing of the glucagon-like peptide-1 receptor.

BACKGROUND AND PURPOSE: The glucagon-like peptide-1 receptor (GLP-1R) belongs to Family B of the G protein-coupled receptor superfamily and is a target for treatment of type 2 diabetes. Family B G protein-coupled receptors contain a putative N-terminal signal peptide, but its role in receptor synthesis and trafficking are unclear. Further, the signal peptide is not cleaved in at least one family member. EXPERIMENTAL APPROACH: We examined receptor glycosylation and the role of the signal peptide in GLP-1R synthesis and trafficking using constructs containing epitope tags at the N- and/or C-terminus and in which the signal peptide sequence was either present or absent. KEY RESULTS: The signal peptide was absolutely required for GLP-1R synthesis but could be substituted to some extent by increasing positive charge in the N-terminal region of the receptor flanking the signal peptide. The signal peptide is cleaved during synthesis and processing of the receptor. An enhanced GFP-epitope tag at the N-terminus of the receptor permitted synthesis of the receptor but blocked signal peptide cleavage and prevented trafficking to the plasma membrane. Cleavage site mutation allowed synthesis of a full-length receptor, blocked signal peptide cleavage and caused retention within the endoplasmic reticulum. CONCLUSIONS AND IMPLICATIONS: Signal peptide cleavage was not essential for receptor synthesis but was obligatory for processing and trafficking of receptors to the plasma membrane. Further, the GLP-1R is subject to N-linked glycosylation and only the mature, fully glycosylated form of the receptor is present in the plasma membrane. Inhibition of glycosylation prevents processing and cell surface expression of the GLP-1R.

J/psi and psi(2S) Radiative Transitions to eta_{c}.

Using 2.45x10;{7} psi(2S) decays collected with the CLEO-c detector at the Cornell Electron Storage Ring we present the most precise measurements of magnetic dipole transitions in the charmonium system. We measure B(psi(2S)-->gammaeta_{c})=(4.32+/-0.16+/-0.60)x10;{-3}, B(J/psi-->gammaeta_{c})/B(psi(2S)-->gammaeta_{c})=4.59+/-0.23+/-0.64, and B(J/psi-->gammaeta_{c})=(1.98+/-0.09+/-0.30)%. We observe a distortion in the eta_{c} line shape due to the photon-energy dependence of the magnetic dipole transition rate. We find that measurements of the eta_{c} mass are sensitive to the line shape, suggesting an explanation for the discrepancy between measurements of the eta_{c} mass in radiative transitions and other production mechanisms.

Racial difference in the correlates of bone mineral content/density and age at peak among reproductive-aged women.

SUMMARY: Racial/ethnic differences were observed in age at peak bone density and their correlates, with whites peaking at least 5 years earlier at the femoral neck than black and Hispanic women. Race-specific standards generated in this study could be useful when interpreting bone densitometry data in young women. INTRODUCTION: The influence of race/ethnicity on bone measurements has not been widely examined. This study identifies age and amount of bone accumulated at peak density and their correlates by race/ethnicity. METHODS: Bone mineral content (BMC) and bone mineral density (BMD) of the spine and femoral neck were measured by dual X-ray absorptiometry in 708 white, black, and Hispanic reproductive-aged women. Race-specific nonlinear models were used to describe the relationship between age and bone measurements, after adjusting for body weight and height. Log-transformed bone measurements were used to determine predictors based on multiple linear regression. RESULTS: Predictors, which were race and site specific, included age, age at menarche, body weight, height, months of depot medroxyprogesterone acetate use, weight-bearing exercise, and alcohol use. Women of all races gained BMC and BMD at the spine up to 30-33 years of age. BMC and BMD of the femoral neck peaked among white women earlier (