Effects of storage, RNA extraction, genechip type, and donor sex on gene expression profiling of human whole blood

BACKGROUND: Gene expression profiling of whole blood may be useful for monitoring toxicological exposure and for diagnosis and monitoring of various diseases. Several methods are available that can be used to transport, store, and extract RNA from whole blood, but it is not clear which procedures alter results. In addition, characterization of interindividual and sex-based variation in gene expression is needed to understand sources and extent of variability. METHODS: Whole blood was obtained from adult male and female volunteers (n = 42) and stored at various temperatures for various lengths of time. RNA was isolated and RNA quality analyzed. Affymetrix GeneChips (n = 23) were used to characterize gene expression profiles (GEPs) and to determine the effects on GEP of storage conditions, extraction techniques, types of GeneChip, or donor sex. Hierarchical clustering and principal component analysis were used to assess interindividual differences. Regression analysis was used to assess the relative impact of the studied variables. RESULTS: Storage of blood samples for >1 week at 4 degrees C diminished subsequent RNA quality. Interindividual GEP differences were seen, but larger effects were observed related to RNA extraction technique, GeneChip, and donor sex. The relative importance of the variables was as follows: storage < genechip < extraction technique < donor sex. CONCLUSION: Sample storage and extraction methods and interindividual differences, particularly donor sex, affect GEP of human whole blood.     

Women in-between' (Strathern, 1995): the ambiguous position of the sister tutor, 1918-1960

The purpose of this article is to explore the ambiguous position of sister tutors, within the nursing and hospital hierarchy between 1918 and 1960. The function of the sister tutor was to train the probationers (student nurses). However, I will argue that the students' education was to come second to the service needs of the hospital, the authority of the matron and desire of the medical profession to maintain control over the nursing curriculum and nursing practice. Therefore sister tutors were caught 'in-between' several opposing forces which together militated against the individual sister tutor's work and the ability of the nursing profession to recruit adequate numbers of senior nurses into the classroom. The recruitment issue was further hampered by the widespread knowledge that much of the sister tutor's work was not student education at all, but organising lectures by medical staff and marking students' notes. In order to gauge the 'official' attitudes to the sister tutors and also the experiences of those who either worked as sister tutors or were taught by them, I used both archival and oral evidence in the research for this article. Pseudonyms have been used throughout for the oral history respondents.     

The chemistry and pharmacology of synthetic cannabinoid SDB‐006 and its regioisomeric fluorinated and methoxylated analogs

Synthetic cannabinoids are the largest and most structurally diverse class of new psychoactive substances, with manufacturers often using isomerism to evade detection and circumvent legal restriction. The regioisomeric methoxy‐ and fluorine‐substituted analogs of SDB‐006 (N‐benzyl‐1‐pentyl‐1H‐indole‐3‐carboxamide) were synthesized and could not be differentiated by gas chromatography–mass spectrometry (GC–MS), but were distinguishable by liquid chromatography–quadrupole time‐of‐flight–MS (LC–QTOF–MS). In a fluorescence‐based plate reader membrane potential assay, SDB‐006 acted as a potent agonist at human cannabinoid receptors (CB₁ EC₅₀ = 19 nM). All methoxy‐ and fluorine‐substituted analogs showed reduced potency compared to SDB‐006, although the 2‐fluorinated analog (EC₅₀ = 166 nM) was comparable to known synthetic cannabinoid RCS‐4 (EC₅₀ = 146 nM). Using biotelemetry in rats, SDB‐006 and RCS‐4 evoked comparable reduction in body temperature (~0.7°C at a dose of 10 mg/kg), suggesting lower potency than the recent synthetic cannabinoid AB‐CHMINACA (>2°C, 3 mg/kg).     

Metabolic syndrome: pathogenesis, medical care and dental implications

BACKGROUND: The dental literature contains little information about metabolic syndrome (MetS) and its dental implications. TYPES OF STUDIES REVIEWED: The authors conducted a MEDLINE search for the period 2000 through 2005, using the term "metabolic syndrome" to define its pathophysiology, medical treatment and dental implications. RESULTS: MetS is the co-occurrence of abdominal obesity, hyper-triglyceridemia, reduced high-density lipoprotein cholesterol levels, hypertension and impaired fasting glucose, which results from consumption of a high-calorie diet and decreased levels of physical activity superimposed on the appropriate genetic setting. Components of MetS synergistically promote the development of atherosclerosis, resulting in myocardial infarction and stroke. CLINICAL IMPLICATIONS: Deteriorating oral health status is associated with worsening of the atherogenic profile. Tooth loss often results in chewing difficulties because of inadequate occlusive surfaces and may lead to alterations in food selection and dietary quality. This, in turn, adversely affects body composition and nutritional status, both of which are related to vascular health. Dentists should develop treatment plans that preserve and restore the dentition, thus ensuring maximum masticatory efficiency and affording patients the optimum opportunity to consume food that will not foster atherogenesis.     

Reaping benefits from intellectual capital

The wealth and value of organizations are increasingly based on intellectual capital. Although acquiring talented individuals and investing in employee learning adds value to the organization, reaping the benefits of intellectual capital involves translating the wisdom of employees into reusable and sustained actions. This requires a culture that creates employee commitment, encourages learning, fosters sharing, and involves employees in decision making. An infrastructure to recognize and embed promising and best practices through social networks, evidence-based practice, customization of innovations, and use of information technology results in increased productivity, stronger financial performance, better patient outcomes, and greater employee and customer satisfaction.