Clinical pharmacology and regulatory consequences of GnRH analogues in prostate cancer

INTRODUCTION: GnRH (gonadotropin-releasing hormone) analogues are long-term known to be safe and effective in the clinical management of hormone-dependent advanced prostate cancer. However, their unusual mechanism of action of de-sensitizing pituitary receptors makes generic market entry challenging. In addition, safety aspects like initial flare-up, breakthrough escape, and miniflares render planning and organization of clinical registration trials a complex project. REGULATORY REQUIREMENTS THERAPEUTIC EQUIVALENCE: Regulatory requirements are high as these medicines are compared to bilateral surgical castration with a 100% success rate. GnRH analogues will be used probably even wider in the near future due to demographic development and extension of indications. However, they are challenged by their antagonistic counterparts, which are avoiding flare-up phenomena. The following article deals with regulatory requirements of GnRH analogues in regard to their clinical characteristics

The metabolic fate of two new psychoactive substances - 2-aminoindane and N-methyl-2-aminoindane - studied in vitro and in vivo to support drug testing

The aim of this study was to characterize the in vitro and in vivo metabolism of 2-aminoindane (2,3-dihydro-1H-inden-2-amine, 2-AI), and N-methyl-2-aminoindane (N-methyl-2,3-dihydro-1H-inden-2-amine, NM-2-AI) after incubations using pooled human liver microsomes (pHLMs), pooled human liver S9 fraction (pS9), and rat urine after oral administration. After analysis using liquid chromatography coupled to high-resolution mass spectrometry, pHLM incubations revealed that 2-AI was left unmetabolized, while NM-2-AI formed a hydroxylamine and diastereomers of a metabolite formed after hydroxylation in beta position. Incubations using pS9 led to the formation of an acetyl conjugation in the case of 2-AI and merely a hydroxylamine for NM-2-AI. Investigations on rat urine showed that 2-AI was hydroxylated also forming diasteromers as described for NM-2-AI or acetylated similar to incubations using pS9. All hydroxylated metabolites of NM-2-AI except the hydroxylamine were found in rat urine as additional sulfates. Assuming similar patterns in humans, urine screening procedures might be focused on the parent compounds but should also include their metabolites. An activity screening using human recombinant N-acetyl transferase (NAT) isoforms 1 and 2 revealed that 2-AI was acetylated exclusively by NAT2, which is polymorphically expressed

An Efficient Molecular Dynamics Scheme for Predicting Dopant Implant Profiles in Semiconductors

We present a highly efficient molecular dynamics scheme for calculating the concentration profile of dopants implanted in group-IV alloy, and III-V zinc blende structure materials. Our program incorporates methods for reducing computational overhead, plus a rare event algorithm to give statistical accuracy over several orders of magnitude change in the dopant concentration. The code uses a molecular dynamics (MD) model, instead of the binary collision approximation (BCA) used in implant simulators such as TRIM and Marlowe, to describe ion-target interactions. Atomic interactions are described by a combination of `many-body' and screened Coulomb potentials. Inelastic energy loss is accounted for using a Firsov model, and electronic stopping is described by a Brandt-Kitagawa model which contains the single adjustable parameter for the entire scheme. Thus, the program is easily extensible to new ion-target combinations with the minimum of tuning, and is predictive over a wide range of implant energies and angles. The scheme is especially suited for calculating profiles due to low energy, large angle implants, and for situations where a predictive capability is required with the minimum of experimental validation. We give examples of using our code to calculate concentration profiles and 2D `point response' profiles of dopants in crystalline silicon, silicon-germanium blends, and gallium-arsenide. We can predict the experimental profile over five orders of magnitude for and channeling and for non-channeling implants at energies up to hundreds of keV.Comment: 10 pages, 7 figures. Proceedings of COSIRES98. Accepted for publication in Nucl. Instrum. and Meth. B. See http://bifrost.lanl.gov/~reed

Liquid Chromatography-High-Resolution Mass Spectrometry-Based In Vitro Toxicometabolomics of the Synthetic Cathinones 4-MPD and 4-MEAP in Pooled Human Liver Microsomes

Synthetic cathinones belong to the most often seized new psychoactive substances on an international level. This study investigated the toxicometabolomics, particularly the in vitro metabolism of 2-(methylamino)-1-(4-methylphenyl)-1-pentanone (4-MPD) and 2-(ethylamino)-1-(4- methylphenyl)-1-pentanone (4-MEAP) in pooled human liver microsomes (pHLM) using untargeted metabolomics techniques. Incubations were performed with the substrates in concentrations ranging from 0, 12.5, and 25 µM. Analysis was done by means of high-performance liquid chromatography coupled to high-resolution mass spectrometry (HPLC-HRMS/MS) in full scan only and the obtained data was evaluated using XCMS Online and MetaboAnalyst. Significant features were putatively identified using a separate parallel reaction monitoring method. Statistical analysis was performed using Kruskal-Wallis test for prefiltering significant features and subsequent hierarchical clustering, as well as principal component analysis (PCA). Hierarchical clustering or PCA showed a distinct clustering of all concentrations with most of the features z-scores rising with the concentration of the investigated substances. Identification of significant features left many of them unidentified but revealed metabolites of both 4-MPD and 4-MEAP. Both substances formed carboxylic acids, were hydroxylated at the alkyl chain, and formed metabolites after combined hydroxylation and reduction of the cathinone oxo group. 4-MPD additionally formed a dihydroxy metabolite and a hydroxylamine. 4-MEAP was additionally found reduced at the cathinone oxo group, N-dealkylated, and formed an oxo metabolite. These findings are the first to describe the metabolic pathways of 4-MPD and to extend our knowledge about the metabolism of 4-MEAP. Findings, particularly the MS data of the metabolites, are essential for setting up metabolite-based toxicological (urine) screening procedures

Simulation of ion track ranges in uranium oxide

Direct comparisons between statistically sound simulations of ion-tracks and published experimental measurements of range densities of iodine implants in uranium dioxide have been made with implant energies in the range of 100-800 keV. Our simulations are conducted with REED-MD (Rare Event Enhanced Domain-following Molecular Dynamics) in order to account for the materials structure in both single crystalline and polycrystalline experimental samples. We find near-perfect agreement between REED-MD results and experiments for polycrystalline target materials.Comment: Eleven pages, four figures

Toxicokinetic studies of the four new psychoactive substances 4-chloroethcathinone, N-ethylnorpentylone, N-ethylhexedrone, and 4-fluoro-alpha-pyrrolidinohexiophenone

Purpose The presented study aimed to elucidate the toxicokinetics of the four synthetic cathinones 4-chloroethcathinone (4-CEC), N-ethylnorpentylone (N-ethylpentylone, ephylone), N-ethylhexedrone (NEH), and 4-fluoro-alpha-pyrrolidinohexiophenone (4-fluoro-alpha-pyrrolidinohexanophenone, 4-F-α-PHP, 4F-alpha-PHP, 4F-PHP). Methods First, their metabolism was studied using human urine and blood samples. Analysis of specimens was performed by liquid chromatography-high resolution tandem mass spectrometry (LC-HRMS/MS) and gas chromatography–mass spectrometry (GC–MS). LC-HRMS/MS was also used to analyze in vitro incubations of the new psychoactive substances using pooled human liver S9 fraction (pS9), to identify the monooxygenases involved in the initial metabolic steps, and determination of plasma concentrations after a standard addition method. Metabolic stability was tested in pooled human liver microsomes incubations analyzed by LC-ion trap MS. Results Using LC-HRMS/MS, 47 metabolites in total were found in patient samples and pS9 incubations. Using GC–MS, 4-CEC, ephylone, NEH, and five of their metabolites were detectable in urine. The following main phase I reactions were observed: carbonyl group reduction, N-deethylation, hydroxylation, lactam formation (4F-PHP), and demethylenation (ephylone). Mainly glucuronidations were observed as phase II reactions besides conjugates with the dicarboxylic acids malonic, succinic, and glutaric acid (4-CEC), sulfation, methylation (both ephylone), and N-acetylation (NEH). A broad range of monooxygenases was involved in the initial steps with exception of NEH (only CYP1A2 and CYP2C19). 4F-PHP had the shortest in vitro half-life (38 min) and highest intrinsic clearance (15.7 mL/min/kg). Plasma concentrations ranged from 0.8 to 8.5 ng/mL. Conclusions Our results are expected to help toxicologists to reliably identify these substances in case of suspected abuse and allow them a thorough risk assessment

Platinum resistance in breast and ovarian cancer cell lines

Breast and ovarian cancers are among the 10 leading cancer types in females with mortalities of 15% and 6%, respectively. Despite tremendous efforts to conquer malignant diseases, the war on cancer declared by Richard Nixon four decades ago seems to be lost. Approximately 21,800 women in the US will be diagnosed with ovarian cancer in 2011. Therefore, its incidence is relatively low compared to breast cancer with 207.090 prognosed cases in 2011. However, overall survival unmasks ovarian cancer as the most deadly gynecological neoplasia. Platinum-based chemotherapy is emerging as an upcoming treatment modality especially in triple negative breast cancer. However, in ovarian cancer Platinum-complexes for a long time are established as first line treatment. Emergence of a resistant phenotype is a major hurdle in curative cancer therapy approaches and many scientists around the world are focussing on this issue. This review covers new findings in this field during the past decade

Systemic therapy of Cushing’s syndrome

Cushing’s disease (CD) in a stricter sense derives from pathologic adrenocorticotropic hormone (ACTH) secretion usually triggered by micro- or macroadenoma of the pituitary gland. It is, thus, a form of secondary hypercortisolism. In contrast, Cushing’s syndrome (CS) describes the complexity of clinical consequences triggered by excessive cortisol blood levels over extended periods of time irrespective of their origin. CS is a rare disease according to the European orphan regulation affecting not more than 5/10,000 persons in Europe. CD most commonly affects adults aged 20–50 years with a marked female preponderance (1:5 ratio of male vs. female). Patient presentation and clinical symptoms substantially vary depending on duration and plasma levels of cortisol. In 80% of cases CS is ACTH-dependent and in 20% of cases it is ACTH-independent, respectively. Endogenous CS usually is a result of a pituitary tumor. Clinical manifestation of CS, apart from corticotropin-releasing hormone (CRH-), ACTH-, and cortisol-producing (malign and benign) tumors may also be by exogenous glucocorticoid intake. Diagnosis of hypercortisolism (irrespective of its origin) comprises the following: Complete blood count including serum electrolytes, blood sugar etc., urinary free cortisol (UFC) from 24 h-urine sampling and circadian profile of plasma cortisol, plasma ACTH, dehydroepiandrosterone, testosterone itself, and urine steroid profile, Low-Dose-Dexamethasone-Test, High-Dose-Dexamethasone-Test, after endocrine diagnostic tests: magnetic resonance imaging (MRI), ultra-sound, computer tomography (CT) and other localization diagnostics. First-line therapy is trans-sphenoidal surgery (TSS) of the pituitary adenoma (in case of ACTH-producing tumors). In patients not amenable for surgery radiotherapy remains an option. Pharmacological therapy applies when these two options are not amenable or refused. In cases when pharmacological therapy becomes necessary, Pasireotide should be used in first-line in CD. CS patients are at an overall 4-fold higher mortality rate than age- and gender-matched subjects in the general population. The following article describes the most prominent substances used for clinical management of CS and gives a systematic overview of safety profiles, pharmacokinetic (PK)-parameters, and regulatory framework

Differential cross section measurements for the production of a W boson in association with jets in proton–proton collisions at √s = 7 TeV

Measurements are reported of differential cross sections for the production of a W boson, which decays into a muon and a neutrino, in association with jets, as a function of several variables, including the transverse momenta (pT) and pseudorapidities of the four leading jets, the scalar sum of jet transverse momenta (HT), and the difference in azimuthal angle between the directions of each jet and the muon. The data sample of pp collisions at a centre-of-mass energy of 7 TeV was collected with the CMS detector at the LHC and corresponds to an integrated luminosity of 5.0 fb[superscript −1]. The measured cross sections are compared to predictions from Monte Carlo generators, MadGraph + pythia and sherpa, and to next-to-leading-order calculations from BlackHat + sherpa. The differential cross sections are found to be in agreement with the predictions, apart from the pT distributions of the leading jets at high pT values, the distributions of the HT at high-HT and low jet multiplicity, and the distribution of the difference in azimuthal angle between the leading jet and the muon at low values.United States. Dept. of EnergyNational Science Foundation (U.S.)Alfred P. Sloan Foundatio