Characterization of AZD8931, a potent reversible small molecule inhibitor against epidermal growth factor receptor (EGFR), erythroblastic leukemia viral oncogene homolog 2 (HER2) and 3 (HER3) with a unique and balanced pharmacological profile

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Background: Successful combined pharmacological inhibition of EGFR, HER2, and HER3 signaling is currently under investigation in the clinic. HERs (erbB receptors including EGFR, erbB2, erbB3, erbB4) undergo various types of alteration and in many cancers HER ligands are produced either by the tumor cells themselves or surrounding stromal cells. These mechanisms of receptor activation all lead to constitutive proliferative and/or survival signaling driven by homo- and/or heterodimerization of the HER family. Characterization of a novel tyrosine kinase inhibitor with a potent and balanced profile against EGFR, HER2 (erbB2), and HER3 (erbB3) has been carried out. Methods: A range of assays has been developed to assess the detailed pharmacology of AZD8931 and understand how the profile of AZD8931 compares with other HER family inhibitors, such as gefitinib and lapatinib. These assays have provided unique insights into the pharmacology of these drugs that result from the varying levels of HER and their associated ligands. Results: Across a number of cell systems, AZD8931 has been shown to be a potent inhibitor of tumor cell growth. This effect is through the ability of AZD8931 to inhibit potently the phosphorylation of EGFR (0.004 μM; 95% CIR: 1.377), HER2 (0.003 μM; 95% CIR: 1.817) and HER3 (0.004 μM; 95% CIR: 1.890) in a balanced manner. Furthermore, when compared to control AZD8931 has significant and dramatic effects on the downstream signaling pathways (pAKT [p=0.002] & pMAK [NS]), apoptotic (M30 [p=0.004]), and proliferative (Ki67 [p<0.0005]) endpoints. The novel agent AZD8931 displays a distinct pharmacological profile compared to both gefitinib and lapatinib. Conclusions: Based on our data as well as published literature, the combined pharmacological inhibition of EGFR, HER2, and HER3 signaling has not yet been tested in the clinic. AZD8931 offers an agent to test the hypothesis that combined inhibition of HER signaling could provide additional clinical benefit in cancer, particularly in the majority of solid tumors that do not overexpress HER2.

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Design, construction, and first commissioning results of superconducting source for ions at NSCL/MSU

A new electron cyclotron resonance ion source (ECRIS) was constructed at the NSCL/MSU to replace the existing SC-ECRIS. This ECRIS operates at 18+14.5 GHz microwave frequencies with a planned upgrade to 24-28 GHz in the second phase of commissioning. A superconducting hexapole coil system produce the radial magnetic field; the axial trapping is produced with six superconducting solenoid coils enclosed in an iron yoke to allow the optimization of the distance between the plasma electrode and the resonant zone in the plasma. We report the details of the design, construction, and initial commissioning results of this new ECRIS.

QTL analysis of body weight and conformation score in commercial broiler chickens using variance component and half-sib analyses

The aim of the study was to investigate quantitative trait loci (QTL) in previously identified regions of chicken chromosomes 1, 4 and 5 relating to 40-day body weights and conformation scores. Half-sib (HS) and variance component analyses were implemented and compared using QTL Express software. Data were from a two-generation design and consisted of 100 dam families nested in 46 sire families with trait values for 2,708 offspring. Chicken chromosome 4 showed nominal significance for QTL affecting body weight and conformation, and linkage was confirmed for both traits on chromosome 5. Results varied according to method of analysis and with common parent in the HS method.

Spiral computed tomography-intravenous cholangiography with three-dimensional reconstructions for imaging the biliary tree

This study aimed to assess the ability of CT-i.v. cholangiography to show the perihilar biliary and cystic duct anatomy and to assess the relative performance of axial, maximum intensity projection and surface rendered displays. We also assessed the correlation between serum bilirubin levels and adequacy of biliary opacification. Spiral CT was carried out following infusion of 100 mL of Biliscopin in 181 patients with suspected biliary disease. The display of biliary anatomy was of high quality, with 91% of patients having good opacification of at least first-order bile ducts and 84% having good opacification of at least third-order right and left hepatic ducts. The quality of biliary opacification correlated inversely to serum bilirubin levels, with levels above two to three times the normal value being associated with lower rates of good opacification. Maximum intensity projection and surface rendered reformats aided anatomical interpretation to a similar degree. The relative frequency of types of perihilar branching patterns and cystic duct junctional anatomy correlated closely to those reported from previous anatomical studies.

Segregation of QTL for production traits in commercial meat-type chickens

This study investigated whether quantitative trait loci (QTL) identified in experimental crosses of chickens provide a short cut to the identification of QTL in commercial populations. A commercial population of broilers was targeted for chromosomal regions in which QTL for traits associated with meat production have previously been detected in extreme crosses. A three-generation design, consisting of 15 grandsires, 608 half-sib hens and over 15 000 third-generation offspring, was implemented within the existing breeding scheme of a broiler breeding company. The first two generations were typed for 52 microsatellite markers spanning regions of nine chicken chromosomes and covering a total of 730 cM, approximately one-fifth of the chicken genome. Using half-sib analyses with a multiple QTL model, linkage was studied between these regions and 17 growth and carcass traits. Out of 153 trait x region comparisons, 53 QTL exceeded the threshold for genome-wide significance while an additional 23 QTL were significant at the nominal 1% level. Many of the QTL affect the carcass proportions and feed intake, for which there are few published studies. Given intensive selection for efficient growth in broilers for more than 50 generations it is surprising that many QTL affecting these traits are still segregating. Future fine-mapping efforts could elucidate whether ancestral mutations are still segregating as a result of pleiotropic effects on fitness traits or whether this variation is due to new mutations.

Inhibitory effect of stiripentol on carbamazepine and saquinavir metabolism in human

AIMS

To characterize the in vitro and in vivo inhibitory effect of stiripentol, a new anticonvulsant, on the metabolism of carbamazepine and saquinavir, which are substrates of CYP3A4.

METHODS

Human liver microsomes and cDNA-expressed CYP enzymes were used for the in vitro experiments. Pharmacokinetic data from epileptic children and healthy adults were used for the carbamazepine and saquinavir in vivo studies, respectively.

RESULTS

Carbamazepine biotransformation to its 10,11-epoxide by human liver microsomes (Vmax = 10.3 nmol min(-1) nmol(-1) P450, apparent Km = 362 microm), cDNA-expressed CYP3A4 (Vmax = 1.17 nmol min(-1) nmol(-1) P450, apparent Km = 119 microm) and CYP2C8 (Vmax = 0.669 nmol min(-1) nmol(-1) P450, apparent Km = 757 microm) was inhibited by stiripentol (IC50 14, 5.1, 37 microM and apparent Ki 3.7, 2.5, 35 microm, respectively). Saquinavir biotransformation to its major metabolite M7 by human liver microsomes (Vmax = 5.7 nmol min(-1) nmol(-1) P450, apparent Km = 0.79 microm) was inhibited by stiripentol (IC50 163 microM, apparent Ki 86 microm). In epileptic children treated with carbamazepine and stiripentol, the plasma concentration ratio of carbamazepine epoxide/carbamazepine was decreased by 65%. The in vivo apparent Ki for stiripentol ranged from 10.5 to 41.4 microm. The pharmacokinetics of saquinavir was not modified by stiripentol in healthy adults. The 95% confidence intervals for the difference for Cmax and AUC of saquinavir between the placebo and stiripentol phase were (-39.8, 39.8) and (-33.2, 112), respectively.

CONCLUSIONS

These results showed that stiripentol was a weak inhibitor of saquinavir metabolism both in vitro and in vivo. In contrast, stiripentol is a potent inhibitor of carbamazepine 10,11-epoxide formation in vitro and in vivo in epileptic patients.

Quantitative trait locus detection in commercial broiler lines using candidate regions

A QTL that explained a large proportion of the phenotypic difference between broiler and layer chickens in an experimental cross was evaluated in a commercial broiler line. A three-generation design, consisting of 15 grandsires, 608 half-sib hens, and more than 50,000 third-generation offspring, was implemented within the existing breeding scheme of a broiler breeding company. Four markers from a candidate region on chicken chromosome 4 were selected for their informativeness in the grandsires and used to genotype the first two generations. Using half-sib analyses, linkage was studied between these markers and 13 growth and carcass traits. The QTL analyses confirmed the presence of significant QTL for body weight (P < 0.01) and residual feed intake (P < 0.05) on chicken chromosome 4. Furthermore, evidence was found for QTL affecting the relative weight of bone and muscle in the thigh. Four more markers were added to increase resolution of the QTL positions. This increased the significance of the QTL for body weight (P < 0.001) and residual feed intake (P < 0.01) and showed evidence (P < 0.05) for additional QTL affecting carcass weight and conformation score. This study showed for the first time that a QTL that explains differences between broilers and layers was segregating in lines that have been selected for body weight over 50 generations. A possible explanation could be a pleiotropic or closely linked effect on fitness-related traits that are not part of the present study. The results demonstrate the feasibility of QTL detection and the potential for marker-assisted selection within a commercial broiler line without altering the existing breeding scheme.

[Development of a self-administered questionnaire to assess women's satisfaction with maternity care]

OBJECTIVES

We describe the development and the validation of a French self-administered questionnaire which measures women satisfaction concerning care given during pregnancy. The analysis includes pregnancy monitoring, hospitalization for delivery and homecoming.

METHODS

We considered the content validity, internal-consistency and the reproducibility by test-retest estimates. This survey also compared the characteristics of respondents and non-respondents.

RESULTS

Response rate was 61% and the rate of reply per question was greater than 90%. Eleven dimensions are identified by principal-components analysis. Ten of them had good Cronbach's alpha coefficients (0.58 to 0.83). The convergence between open comments and questions and between the different methods to measure satisfaction was good. The test-retest estimates for each dimension were correct.

CONCLUSION

This questionnaire is reliable. It is a valid tool for evaluation of satisfaction after pregnancy. Designed to be sent to the woman's residence 2 months after childbirth, it can be easily used in common practice.

The use of speech therapy in the treatment of globus pharyngeus patients. A randomised controlled trial

INTRODUCTION

Globus sensation is a common condition accounting for about 4% of new referrals to an ENT clinic. A review of current theories on the cause of globus sensation concludes that no single aetiology is responsible. Wareing et al believed that globus sensation might in part be associated with excessive laryngeal and pharyngeal tension. The aim of this study was to substantiate in a controlled prospective manner the results of a non-controlled study by the same authors that certain speech therapy techniques improved globus symptoms.

METHODS

1. 36 patients with typical globus pharyngeus symptoms were randomised to treatment with speech therapy (Study group) and reassurance by nurse practitioner (Control group). The following data was collated for each patient: duration and type of globus symptoms (sense of a lump in the throat/throat irritation), severity of globus symptoms on a visual analogue scale, fibreoptic laryngoscopy, full blood count, barium swallow. 2. At the end of 3 months, patients in both groups marked on the visual analogue scale the severity of their symptoms.

RESULTS

There was a significant improvement in the globus symptom scores in the speech therapy group compared to pre-intervention scores (p < 0.001, Wilcoxon rank test). There was also a significant improvement in globus symptoms in the speech therapy group compared to controls (p < 0.001, Mann-Whitney U test).

CONCLUSION

Initial results suggest that patients with globus pharyngeus symptoms benefit from speech therapy.

[Long-term efficacy and tolerance of stiripentaol in severe myoclonic epilepsy of infancy (Dravet's syndrome)]

OBJECTIVE

To describe the long term efficacy and tolerance of stiripentol associated with valproate and clobazam in an exhaustive cohort of patients with severe myoclonic epilepsy of infancy (Dravet's syndrome), in which short term efficacy of such a treatment has recently been demonstrated in a placebo-controlled trial.

RESULTS

In 46 patients the frequency and the duration of seizures was significantly reduced (p < 0.001) as well as the number of convulsive status at a median of three-year follow-up. Ten patients were dramatically improved (seizures significantly decreased in number [p = 0.002] and duration [p = 0.002] and status epilepticus disappeared), 20 were moderately improved (seizures significantly decreased in duration [p = 0.001] and status were less numerous), four had no response and efficacy was non evaluable in 12 mainly because of adverse events. Efficacy was better in the youngest patients. The most frequent adverse events were loss of appetite and loss of weight. They could be so severe in patients over 12 years of age that the stiripentol dosage could not be increased to 50 mg kg-1 j-1.

CONCLUSION

This follow-up study shows that stiripentol added to valproate and clobazam maintains its efficacy at long term in children with severe myoclonic epilepsy of infancy and suggests that the tritherapy should be introduced as early as possible in these patients in order to suppress the convulsive status epilepticus.

Remineralization of enamel subsurface lesions by sugar-free chewing gum containing casein phosphopeptide-amorphous calcium phosphate

Casein phosphopeptide-amorphous calcium phosphate nanocomplexes (CPP-ACP) exhibit anticariogenic potential in laboratory, animal, and human in situ experiments. The aim of this study was to determine the ability of CPP-ACP in sugar-free chewing gum to remineralize enamel subsurface lesions in a human in situ model. Thirty subjects in randomized, cross-over, double-blind studies wore removable palatal appliances with six human-enamel half-slabs inset containing sub-surface demineralized lesions. The appliances were inserted immediately before gum-chewing for 20 min and then retained for another 20 min. This was performed four times per day for 14 days. At the completion of each treatment, the enamel half-slabs were paired with their respective demineralized control half-slabs, embedded, sectioned, and subjected to microradiography and densitometric image analysis, for measurement of the level of remineralization. The addition of CPP-ACP to either sorbitol- or xylitol-based gum resulted in a dose-related increase in enamel remineralization, with 0.19, 10.0, 18.8, and 56.4 mg of CPP-ACP producing an increase in enamel remineralization of 9, 63, 102, and 152%, respectively, relative to the control gum, independent of gum weight or type.