Compliance with GLP standards and management in analytical laboratories: current status

 Analytical laboratories in Japan, operating more often as departments within a company than as independent contractors, have to contend with different good laboratory practice (GLP) standards. Problems also occur in the analytical laboratories which must comply with GLP, good manufacturing practice (GMP) and good clinical practice (GCP) regulations within the same facility. The status of these GLP-complied analytical laboratories is reviewed with regard to assurance program, validation method, laboratory information management, and security systems. The differences in the responsible authorities and scopes under the six GLPs are also briefly described. Analytical tests in GLP are not itemized as a test for accreditation. Therefore, the accreditation of analytical laboratories in Japan is currently granted as a part of ISO 9000 approvals. Received: 27 September 1996 Accepted: 11 November 1996     

Quinazoline Based HDAC Dual Inhibitors as Potential Anti-Cancer Agents

Cancer is the most devastating disease and second leading cause of death around the world. Despite scientific advancements in the diagnosis and treatment of cancer which can include targeted therapy, chemotherapy, endocrine therapy, immunotherapy, radiotherapy and surgery in some cases, cancer cells appear to outsmart and evade almost any method of treatment by developing drug resistance. Quinazolines are the most versatile, ubiquitous and privileged nitrogen bearing heterocyclic compounds with a wide array of biological and pharmacological applications. Most of the anti-cancer agents featuring quinazoline pharmacophore have shown promising therapeutic activity. Therefore, extensive research is underway to explore the potential of these privileged scaffolds. In this context, a molecular hybridization approach to develop hybrid drugs has become a popular tool in the field of drug discovery, especially after witnessing the successful results during the past decade. Histone deacetylases (HDACs) have emerged as an important anti-cancer target in the recent years given its role in cellular growth, gene regulation, and metabolism. Dual inhibitors, especially based on HDAC in particular, have become the center stage of current cancer drug development. Given the growing significance of dual HDAC inhibitors, in this review, we intend to compile the development of quinazoline based HDAC dual inhibitors as anti-cancer agents.     

Wolfe步长规则下约束优化问题的共轭梯度投影算法

本文研究了约束优化问题min x∈Ωf(x).利用共轭梯度算法与GLP梯度投影思想相结合的方法,构造了一个新的共轭梯度投影算法,并在Wolfe线搜索下获得了该算法的全局收敛性结果.     

Validating automated analytical instruments to meet regulatory and quality standard requirements

Analytical laboratories are more and more faced to meet official regulatory requirements as described in FDA and EPA good laboratory practice, good automated laboratory practice and good manufacturing practice regulations or to officially establish quality systems, such as specified in the ISO 9000 Series quality standards, in the ISO Guide 25 or in the EN 45001 guidelines. The impact on analytical instrumentation will be the requirement for stringent validation of analytical equipment and methods which increase the overall analysis costs. An overview is presented on the validation requirements using e.g. gas chromatography, high performance liquid chromatography, capillary electrophoresis and UV-visible spectroscopy and on the strategy to meet such needs at minimal extra costs with the help of an instrument vendor. It is recommended to use instrument hardware that has already built-in tools for self-verification and which is to be validated at the vendor's site. Performance testing in the user's laboratory is done using standard operating procedures as supplied with the instrument. If resources in the user's laboratory are limited, the performance verification is done by the vendor. Software and the entire computer system is validated prior to shipment at the vendor's site. Acceptance testing is done in the user's environment following the vendor recommendations. Analytical methods are validated automatically at the end of method development using a dedicated software. The software can be customized such that it can also be used for daily automated system suitability testing. Security and integrity of analytical data are ensured by saving the raw data together with instrument conditions and instrument log-books in check-sum protected binary register files for long-term archiving.     

Ab initio modelling of the N-terminal domain of the secretin receptors

G protein coupled receptors of the secretin family are activated by peptide hormones of about 30 residues in length. There is considerable sequence homology within both the hormone and receptor families. The receptors possess in addition to the integral membrane domain a characteristic extracellular domain of about 120 residues in length, having conserved cysteine residues, which are involved in disulphide bridge formation, and tryptophanes, which have been shown to be critical for hormone binding. This extracellular domain does not have detectable homology to any known protein fold. In order to be able to propose a structure for this domain we have used ab initio prediction methods combined with constraints based on experimental results for the disulphide connectivity. The results of computational tools for predicting secondary structure and accessibility, together with ligand binding and mutational data and other structural considerations were used in the ab initio protein folding programs DRAGON and GADGET and also the simpler program RAMBLE, which was able to explore different permutations of disulphide bond connectivity, tryptophan side chain orientation and chain topology. The methods generated a limited number of plausible models but no single unique solution was found under the constraints. One of these was refined into a full atomic model that contained a possible peptide binding site comprising the most conserved residues.     

A novel hybrid solid-like fluid-like (SLFL) method for the simulation of dry granular flows

This paper proposes a novel hybrid method to simulate the dry granular flow of materials over a wide range of inertial numbers that simultaneously covers the quasi-static and dense granular flow regimes. To overcome the lack of incremental objectivity whenever large deformations occur in solid-like regimes and to remove computational singularities in fluid-like regimes close to rest, the elastic–perfectly plastic theory based on the Drucker–Prager yield criterion is combined with the theory of dense granular flows. By implementing some new modifications at the boundaries and removing all ghost particles, smoothed particle hydrodynamics (SPH) is used as the framework for the method. A number of benchmark problems have been solved to show the capabilities of the new modified SPH method. Precise prediction of both location and pressure makes the modifications comparable with the previous works on SPH. Finally, the method is used to solve the classic 2D dry granular cliff collapse problem and to model dry granular material flow inside a rotary drum. The outcomes of the numerical simulation show good agreement with tabletop experiments and published results.     

基于修正拟牛顿方程的两阶段步长非单调稀疏对角变尺度梯度投影算法

基于修正拟牛顿方程, 利用Goldstein-Levitin-Polyak (GLP)投影技术, 建立了 求解带凸集约束的优化问题的两阶段步长Zhang H.C.非单调变尺度梯度投影方法, 证明了算法的全局收敛性. 数值实验表明算法是有效的, 适合求解大规模问题.     

Determination of GDC‐0980 (apitolisib), a small molecule dual phosphatidylinositide 3‐kinase/mammalian target of rapamycin inhibitor in dog plasma by LC‐MS/MS to support a GLP toxicology study

An LC‐MS/MS method for the determination of GDC‐0980 (apitolisib) concentrations in dog plasma has been developed and validated for the first time to support pre‐clinical drug development. Following protein precipitation with acetonitrile, the resulting samples were analyzed using reverse‐phase chromatography on a Metasil AQ column. The mass analysis was performed on a triple quadruple mass spectrometer coupled with an electrospray interface in positive ionization mode. The selected reaction monitoring transitions monitored were m/z 499.3 → 341.1 for GDC‐0980 and m/z 507.3 → 341.1 for IS. The method was validated over the calibration curve range 0.250–250 ng/mL with linear regression and 1/x² weighting. Relative standard deviation (RSD) ranged from 0.0 to 10.9% and accuracy ranged from 93.4 to 113.6% of nominal. Stable‐labeled internal standard GDC‐0980‐d₈ was used to minimize matrix effects. This assay was used for the measurement of GDC‐0980 dog plasma concentrations to determine toxicokinetic parameters after oral administration of GDC‐0980 (0.03, 0.1 and 0.3 mg/kg) to beagle dogs in a GLP toxicology study. Peak concentration ranged from 3.23 to 84.9 ng/mL. GDC‐0980 was rapidly absorbed with a mean time to peak concentration ranging from 1.3 to 2.4 h. Mean area under the concentration–time curve from 0 to 24 hours ranged from 54.4 to 542 ng h/mL. Copyright © 2015 John Wiley & Sons, Ltd.