The future of laboratory medicine - A 2014 perspective.

Predicting the future is a difficult task. Not surprisingly, there are many examples and assumptions that have proved to be wrong. This review surveys the many predictions, beginning in 1887, about the future of laboratory medicine and its sub-specialties such as clinical chemistry and molecular pathology. It provides a commentary on the accuracy of the predictions and offers opinions on emerging technologies, economic factors and social developments that may play a role in shaping the future of laboratory medicine

How norms make causes

This paper is on the problem of causal selection and comments on Collingwood's classic paper "The so-called idea of causation". It discusses the relevance of Collingwood’s control principle in contemporary life sciences and defends that it is not the ability to control, but the willingness to control that often biases us towards some rather than other causes of a phenomenon. Willingness to control is certainly only one principle that influences causal selection, but it is an important one. It shows how norms make causes

Three DNA polymerases, recruited by different mechanisms, carry out NER repair synthesis in human cells

Nucleotide excision repair (NER) is the most versatile DNA repair system that deals with the major UV photoproducts in DNA, as well as many other DNA adducts. The early steps of NER are well understood, whereas the later steps of repair synthesis and ligation are not. In particular, which polymerases are definitely involved in repair synthesis and how they are recruited to the damaged sites has not yet been established. We report that, in human fibroblasts, approximately half of the repair synthesis requires both polκ and polδ, and both polymerases can be recovered in the same repair complexes. Polκ is recruited to repair sites by ubiquitinated PCNA and XRCC1 and polδ by the classical replication factor complex RFC1-RFC, together with a polymerase accessory factor, p66, and unmodified PCNA. The remaining repair synthesis is dependent on polɛ, recruitment of which is dependent on the alternative clamp loader CTF18-RFC

CYP2D6 function moderates the pharmacokinetics and pharmacodynamics of 3,4-methylene-dioxymethamphetamine in a controlled study in healthy individuals

The role of genetic polymorphisms in cytochrome (CYP) 2D6 involved in the metabolism of 3,4-methylene-dioxymethamphetamine (MDMA, ecstasy) is unclear. Effects of genetic variants in CYP2D6 on the pharmacokinetics and pharmacodynamic effects of MDMA were characterized in 139 healthy individuals (70 men, 69 women) in a pooled analysis of eight double-blind, placebo-controlled crossover studies. In CYP2D6 poor metabolizers, the maximum concentrations (Cmax) of MDMA and its active metabolite 3,4-methylene-dioxyamphetamine were +15 and +50% higher, respectively, compared with extensive metabolizers and the Cmax of the inactive metabolite 4-hydroxy-3-methoxymethamphetamine was 50-70% lower. Blood pressure and subjective drug effects increased more rapidly after MDMA administration in poor metabolizers than in extensive metabolizers. In conclusion, the disposition of MDMA and its effects in humans are altered by polymorphic CYP2D6 activity, but the effects are small because of the autoinhibition of CYP2D6

Polymorphisms of pyrimidine pathway enzymes encoding genes and HLA-B*4001 carriage in stavudine-associated lipodystrophy in HIV-infected patients

: To assess in a cohort of Caucasian patients exposed to stavudine (d4T) the association of polymorphisms in pyrimidine pathway enzymes and HLA-B*4001 carriage with HIV lipodystrophy syndrome (HALS). 336 patients, 187 with HALS and 149 without HALS, and 72 controls were recruited. HALS was associated with the presence of a low expression, thymidylate synthase (TS) genotype polymorphism. Methylene-tetrahydrofolate reductase (MTHFR) gene polymorphisms and HLA-B*4001 carriage were not associated with HALS or d4T-TP intracellular levels. In conclusion HALS is associated with combined low-expression TS and MTHFR associated with high activity polymorphisms but not with HLA-B*4001 carriage.: L'objectiu de l'estudi es avaluar en una cohort de pacients caucàsics exposats a estavudina, l'associació de polimorfismes dels enzims de la via de la pirimidina: timidilat sintasa (TS) i metilentetrahidrofolat reductasa (MTHFR) i l'alel HLA-B * 4001 amb la lipodistròfia. Van ser reclutats 336 pacients; 187 amb lipodistròfia i 149 sense lipodistròfia i 72 subjectes sans. La lipodistròfia es va associar amb la presència d'una baixa expressió dels polimorfismes genètics de l 'enzim TS, sobretot en combinació amb polimorfismes d'alta activitat de l'enzim MTHFR però no amb l' HLA-B * 4001

Preoperative fasting protects against renal ischemia-reperfusion injury in aged and overweight mice

Ischemia-reperfusion injury (IRI) is inevitable during kidney transplantation leading to oxidative stress and inflammation. We previously reported that preoperative fasting in young-lean male mice protects against IRI. Since patients are generally of older age with morbidities possibly leading to a different response to fasting, we investigated the effects of preoperative fasting on renal IRI in aged-overweight male and female mice. Male and female F1-FVB/C57BL6-hybrid mice, average age 73 weeks weighing 47.2 grams, were randomized to preoperative ad libitum feeding or 3 days fasting, followed by renal IRI. Body weight, kidney function and survival of the animals were monitored until day 28 postoperatively. Kidney histopathology was scored for all animals and gene expression profiles after fasting were analyzed in kidneys of young and aged male mice. Preoperative fasting significantly improved survival after renal IRI in both sexes compared with normal fed mice. Fasted groups had a better kidney function shown by lower serum urea levels after renal IRI. Histopathology showed less acute tubular necrosis and more regeneration in kidneys from fasted mice. A mRNA analysis indicated the involvement of metabolic processes including fatty acid oxidation and retinol metabolism, and the NRF2-mediated stress response. Similar to young-lean, healthy male mice, preoperative fasting protects against renal IRI in aged-overweight mice of both genders. These findings suggest a general protective response of fasting against renal IRI regardless of age, gender, body weight and genetic background. Therefore, fasting could be a non-invasive intervention inducing increased oxidative stress resistance in older and overweight patients as well

Pharmacogenetics of ecstasy: CYP1A2, CYP2C19, and CYP2B6 polymorphisms moderate pharmacokinetics of MDMA in healthy subjects

In vitro studies showed that CYP2C19, CYP2B6, and CYP1A2 contribute to the metabolism of 3,4-methylenedioxymethamphetamine (MDMA, ecstasy) to 3,4-methylenedioxyamphetamine (MDA). However, the role of genetic polymorphisms in CYP2C19, CYP2B6, and CYP1A2 in the metabolism of MDMA in humans is unknown. The effects of genetic variants in these CYP enzymes on the pharmacokinetics and pharmacodynamics of MDMA were characterized in 139 healthy subjects (69 male, 70 female) in a pooled analysis of eight double-blind, placebo-controlled studies. MDMA-MDA conversion was positively associated with genotypes known to convey higher CYP2C19 or CYP2B6 activities. Additionally, CYP2C19 poor metabolizers showed greater cardiovascular responses to MDMA compared with other CYP2C19 genotypes. Furthermore, the maximum concentration of MDA was higher in tobacco smokers that harbored the inducible CYP1A2 rs762551 A/A genotype compared with the non-inducible C-allele carriers. The findings indicate that CYP2C19, CYP2B6, and CYP1A2 contribute to the metabolism of MDMA to MDA in humans. Additionally, genetic polymorphisms in CYP2C19 may moderate the cardiovascular toxicity of MDMA