The concordance between nonclinical and phase I clinical cardiovascular assessment from a cross-company data sharing initiative.

It is widely accepted that more needs to be done to bring new, safe, and efficacious drugs to the market. Cardiovascular toxicity detected both in early drug discovery as well as in the clinic, is a major contributor to the high failure rate of new molecules. The growth of translational safety offers a promising approach to improve the probability of success for new molecules.

Automatic analysis of the micronucleus test in primary human lymphocytes using image analysis.

The in vitro micronucleus test (MNT) is a well-established test for early screening of new chemical entities in industrial toxicology. For assessing the clastogenic or aneugenic potential of a test compound, micronucleus induction in cells has been shown repeatedly to be a sensitive and a specific parameter. Various automated systems to replace the tedious and time-consuming visual slide analysis procedure as well as flow cytometric approaches have been discussed.

Differentiating electrophysiological effects and cardiac safety of drugs based on the electrocardiogram: a blinded validation.

Background: The ventricular components (QRS and QT) on the electrocardiogram (ECG) depend on the properties of ventricular action potentials that can be modulated by drugs via specific ion channels. However, the correlation of ECG ventricular waveforms with underlying ion actions is not well established and has been extensively debated.

Objective: To conduct a blinded in vitro assessment of the ionic mechanisms for drug-induced ECG changes.

Best practices for heart failure: a focused review.

Heart failure (HF) is a progressive condition and is associated with high patient mortality rates and frequent hospitalizations. This article provides an overview of clinical, self-management support, and care transitions best practices for HF care in the home care sector. Clinicians armed with competencies in HF management are positioned to meet the 3-part aim of healthcare reform: improved health, better care, and lower cost.

How do the top 12 pharmaceutical companies operate safety pharmacology?

Introduction: How does safety pharmacology operate in large pharmaceutical companies today? By understanding our current position, can we prepare safety pharmacology to successfully navigate the complex process of drug discovery and development?

Methods: A short anonymous survey was conducted, by invitation, to safety pharmacology representatives of the top 12 pharmaceutical companies, as defined by 2009 revenue figures. A series of multiple choice questions was designed to explore group size, accountabilities, roles and responsibilities of group members, outsourcing policy and publication record.

Results: A 92% response rate was obtained.

Miniaturized flow cytometry-based in vitro primary human lymphocyte micronucleus assay-validation study.

Most in vitro mammalian genotoxicity assays show a low specificity (high rate of irrelevant positive results), and therefore, lead to an increase in follow-up in vivo genotoxicity testing. One of the sources of the high rate of in vitro irrelevant positive results that find no confirmation in in vivo studies may be the characteristics of the test system used. It has been shown that cells that are p53 deficient or carry an alteration in DNA repair genes may be more prone to produce high rate of false/irrelevant positive results.

In vitro primary human lymphocyte flow cytometry based micronucleus assay: simultaneous assessment of cell proliferation, apoptosis and MN frequency.

In order to minimise the number of positive in vitro cytogenetic results which are not confirmed in rodent carcinogenicity tests, biological systems that are p53 and DNA repair proficient should be recommended. Moreover, an appropriate cytotoxicity parameter for top dose selection should be considered. Recent International Conference on Harmonisation draft S2 and Organisation for Economic Co-operation and Development (OECD) 487 guideline accepted the in vitro micronucleus test (MNT) as a valid alternative method for in vitro chromosome aberration test within the in vitro cytogenetic test battery.

How can we improve our understanding of cardiovascular safety liabilities to develop safer medicines?

Given that cardiovascular safety liabilities remain a major cause of drug attrition during preclinical and clinical development, adverse drug reactions, and post-approval withdrawal of medicines, the Medical Research Council Centre for Drug Safety Science hosted a workshop to discuss current challenges in determining, understanding and addressing 'Cardiovascular Toxicity of Medicines'. This article summarizes the key discussions from the workshop that aimed to address three major questions: (i) what are the key cardiovascular safety liabilities in drug discovery, drug development and clinical practice? (ii) how good are preclinical and clinical strategies for detecting cardiovascular liabilities? and (iii) do we have a mechanistic understanding of these liabilities? It was concluded that in order to understand, address and ultimately reduce cardiovascular safety liabilities of new therapeutic agents there is an urgent need to: • Fully characterize the incidence, prevalence and impact of drug-induced cardiovascular issues at all stages of the drug development process. • Ascertain the predictive value of existing non-clinical models and assays towards the clinical outcome.

Theory-based telehealth and patient empowerment.

Health care technology holds great potential to improve the quality of health care delivery. One effective technology is remote patient monitoring, whereby patient data, such as vital signs or symptom reports, are captured from home monitoring devices and transmitted to health care professionals for review. The use of remote patient monitoring, often referred to as telehealth, has been widely adopted by health care providers, particularly home care agencies.

Follow-up actions from positive results of in vitro genetic toxicity testing.

Appropriate follow-up actions and decisions are needed when evaluating and interpreting clear positive results obtained in the in vitro assays used in the initial genotoxicity screening battery (i.e., the battery of tests generally required by regulatory authorities) to assist in overall risk-based decision making concerning the potential effects of human exposure to the agent under test.

A flow cytometry based in vitro micronucleus assay in TK6 cells--validation using early stage pharmaceutical development compounds.

The micronucleus test (MNT) is a well established test for detecting clastogenic and aneugenic compounds. Despite the assay's advantages, the MNT may produce false positive and false negative results in some conditions. This fact may be related to the underestimation of apoptosis or necrosis, the p53 status of the cell system or the cytotoxicity assay, and the top dose selection.

High-content micronucleus assay in genotoxicity profiling: initial-stage development and some applications in the investigative/lead-finding studies in drug discovery.

This article describes the first step toward full (that includes conditions for both absence and presence of metabolic activation) validation and drug discovery application of a 96-well, automated, high-content micronucleus (HCMN) assay. The current validation tests were performed using Chinese hamster ovary cells, in the absence of metabolic activation, against three distinct sets of drug-like compounds that represent all stages of a drug discovery pipeline. A compound categorization scheme was created based on quantitative relationships between micronucleus (MN) signals, cytotoxicity, and compound solubility.

Flow cytometry peripheral blood micronucleus test in vivo: determination of potential thresholds for aneuploidy induced by spindle poisons.

Non-DNA binding genotoxins (e.g., aneugens), unlike DNA-binding genotoxins, are theoretically expected to show thresholded concentration-effect response curves.

Cytogenetic assessment of methylphenidate treatment in pediatric patients treated for attention deficit hyperactivity disorder.

Methylphenidate (MPH, Ritalin), has been prescribed to treat attention deficit/hyperactivity disorder (ADHD) since its approval by the FDA over 50 years ago. Diagnoses of pediatric patients with ADHD and the administration of MPH to treat the symptoms have increased in prevalence in recent years. A 2005 study by El-Zein et al.

Telehealth infection control: a movement toward best practice.

As healthcare transitions to the home environment, there is an increasing need to prevent and control infections traced to telehealth equipment. Background information about infection control is presented, and the need for a survey of agency cleaning policies is described. Findings from 31 agencies using telehealth equipment are described followed by suggested Best Practice Guidelines for the cleaning of telehealth equipment.

Depression revealed: the need for screening, treatment, and monitoring.

Depression is common among both the elderly and those with chronic conditions. Unidentified and inadequately treated depression in home health patients has serious and costly consequences. The authors argue that many negative consequences can be avoided by careful management.

Repair of sparfloxacin-induced photochemical DNA damage in vivo.

The induction and subsequent repair of photochemically induced DNA damage by sparfloxacin was assessed in different tissues of juvenile Wistar rats. The animals were treated once orally with 500 mg kg(-1) of sparfloxacin and irradiated 3 hours later with 7 J cm(-2) UVA. Induction and repair of DNA damage was studied in the skin, retina and cornea using the alkaline comet assay.

Selective block of IKs plays a significant role in MAP triangulation induced by IKr block in isolated rabbit heart.

Introduction: The role of IKr (rapidly-activating delayed rectifier K(+) current) block in triangulation of monophasic action potentials (MAP) and in development of torsade de pointes (TdP) arrhythmia is known. Combined IKr and IKs (slowly-activating delayed rectifier K(+) current) block has been demonstrated to promote TdP. The aim of this study was to describe a possible implication of IKs block in MAP triangulation.

Relevance of in vitro SCREENIT results for drug-induced QT interval prolongation in vivo: a database review and analysis.

Introduction: The use of an isolated rabbit heart model (SCREENIT) to predict drug-induced QTc prolongation in animals was assessed using hERG and telemetry data.

Purpose: We compiled data from (i) hERG assay (IC50s), (ii) SCREENIT assay (APD60) and (iii) in vivo non-rodent telemetry studies (QTc interval) and evaluated the reliability of APD60 to fit with IC50s and QTc prolongation using the ratio to free plasma level (FPL). Eighty-two compounds were separated into three classes based on hERG IC50s (class I: IC50s< or =1 microM, n=7; class II: IC50s>1 microM to < or =10 microM, n=15; class III: IC50s>10 microM, n=60).

Home-based chronic care. An expanded integrative model for home health professionals.

The Chronic Care Model (CCM) developed by is an influential and accepted guide for the care of patients with chronic disease. Wagner acknowledges a current healthcare focus on acute care needs that often circumvents chronic care coordination. He identifies the need for a "division of labor" to assist the primary care physician with this neglected function.

Patient education. Timeless principles of learning: a solid foundation for enhancing chronic disease self-management.

The use of evidence-based principles of learning can contribute to the empowerment of patients as they adopt self-management skills aligned with healthy behaviors. This article, jointly written by a nurse and an educator, describes these timeless principles and how home care clinicians and patients benefit from their use.

Detection of photogenotoxicity in skin and eye in rat with the photo comet assay.

Photosensitizing drugs increase the sensitivity of the skin and the eye toward normally harmless sunlight conditions and are known to enhance the induction of skin tumors or severe injuries to the eye. The photogenotoxicity of five common drugs (sparfloxacin, dacarbazine, chlorpromazine and 8-methoxypsoralen, promazine) was investigated in the skin as well as in the retina and cornea of Wistar rats. The compounds were administered once orally by gavage and the resulting DNA damage was analyzed in the newly developed in vivo photo comet assay.

The photo comet assay--a fast screening assay for the determination of photogenotoxicity in vitro.

Different classes of chemicals can induce a phototoxic effect by absorbing light energy within the wavelength range of sunlight. The assessment of photo-safety is therefore an obligatory part of the development of new drugs. Ten UV-vis (280-800nm)-absorbing compounds (ketoprofen, promazine, chlorpromazine, dacarbazine, acridine, lomefloxacin, 8-methoxypsoralen, chlorhexidine, titanium dioxide, octylmethoxycinnamate) were tested for their photogenotoxic potential in the alkaline comet assay in the presence and absence of UV-vis.

Comparison of the peripheral blood micronucleus test using flow cytometry in rat and mouse exposed to aneugens after single-dose applications.

Detection of clastogenic compounds in the peripheral blood micronucleus test (MNT) in rats is a well-established methodology. However, the results obtained on the induction of micronuclei by aneugens in rat peripheral blood are controversial. Our aim was a comparative evaluation of the peripheral blood flow cytometry MNT in Wistar Han rat and CD1 mouse exposed to three aneugens (vinblastine, vincristine and colchicine) after single-dose applications.