Current drug targets
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Current drug targets · Jun 2012
ReviewIs preoperative endoscopic biliary drainage indicated for jaundiced patients with resectable pancreatic cancer?
The role of preoperative biliary drainage (PBD) in the management of jaundiced patients with resectable pancreatic cancer (RPC) is controversial. Obstructive jaundice determines hepatic dysfunction which can increase the operative risks. Experimental studies demonstrated that PBD could be associated with improved surgical outcomes. ⋯ The latter is still considered the first step for jaundiced patients when they present with cholangitis, intense pruritus or severe jaundice; surgery cannot be scheduled within 7-10 days from the diagnosis; neoadjuvant chemoradiation is planned, as part of the treatment. While endoscopic PBD is considered the preferred approach, there is still controversy about the type of biliary stent which should be used. Emerging data support the insertion of short (4-6 cm) biliary self-expandable metallic stent, especially if surgery is not immediately planned.
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Current drug targets · Dec 2011
ReviewSelective estrogen receptor modulators and aromatase inhibitors for breast cancer chemoprevention.
In premenopausal women, tamoxifen for 5 years reduces the risk of estrogen receptor (ER) - positive breast cancer for at least 10 years. Women < 50 years of age experience fewer serious side effects. Vascular and vasomotor events do not persist after treatment regardless of age. ⋯ No evidence exists establishing whether a reduction in breast cancer risk from either agent translates into reduced breast cancer mortality. Overall quality of life is similar with raloxifene or tamoxifen, but the incidence of dyspareunia, weight gain, and musculoskeletal complaints is higher with raloxifene use, whereas vasomotor symptoms, bladder incontinence, gynecologic symptoms, and leg cramps were higher with tamoxifen use. Ongoing randomized, placebo-controlled trials investigating the use of third-generation aromatase inhibitors in the chemoprevention of breast cancer in postmenopausal women include the NCIC Clinical Trials Group MAP3 (ExCel) Trial (Exemestane in Preventing Cancer in Postmenopausal Women at Increased Risk of Developing Breast Cancer), and the IBIS-II trial.71 The North American MAP3 study randomized patients to exemestane or placebo in patients who refuse treatment with a SERM, and the international IBIS-II trial compares anastrozole for 5 years versus placebo for chemoprevention in patients at increased risk.
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Current drug targets · Nov 2011
ReviewBleeding and acute coronary syndromes: defining, predicting, and managing risk and outcomes.
Acute coronary syndromes (ACS) continue to have a large impact on morbidity and mortality in the United States. Over the last two decades, there have been several advancements in the care of patients with ACS. ⋯ Studies have found an association between bleeding and subsequent mortality and morbidity in ACS patients; therefore, minimizing bleeding risk has become a priority. This review describes the prevalence of bleeding during ACS management, risk for bleeding, and strategies to reduce bleeding risk.
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Current drug targets · May 2011
ReviewGenetic polymorphisms of ATP-binding cassette transporters ABCB1 and ABCC2 and their impact on drug disposition.
The ATP-binding cassette (ABC) transporter superfamily comprises membrane proteins that translocate a variety of substrates across extra- and intra-cellular membranes, and act as efflux proteins. ABC transporters are characterised by the presence of genetic polymorphisms mainly represented by single nucleotide polymorphisms (SNPs), some of which having an impact on their activity. Besides physiological substances, drugs are also substrates of some ABC transporters, mainly ABCB1, ABCC1, ABCC2, ABCC3 and ABCG2. ⋯ For different reasons discussed in this paper, the effect of ABCB1 and/or ABCC2 polymorphisms on drug concentrations in blood is not always easy to interpret and to correlate with pharmacological effects. In contrast, intracellular or target tissue drug concentrations appear more directly influenced by these polymorphisms, as illustrated with intralymphocyte concentrations for immunosupressants and antiretrovirals or with cerebrospinal fluid (CSF) concentrations for antiepileptics and antidepressants. Further research on intracellular and/or target tissue drug concentrations are still needed to better characterise the PK-PG (pharmacogenetics) relationship involving ABC transporters.
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Current drug targets · May 2011
ReviewThe ryanodine receptor: a pivotal Ca2+ regulatory protein and potential therapeutic drug target.
The ryanodine receptor (RyR) calcium release channel is an essential intracellular ion channel that is central to Ca(2+) signaling and contraction in the heart and skeletal muscle. The rapid release of Ca(2+) from the internal sarcoplasmic reticulum Ca(2+) stores through the RyR during excitation-contraction coupling is facilitated by the unique arrangement of the surface and sarcoplasmic reticulum membrane systems. Debilitating and sometimes fatal skeletal and cardiomyopathies result from changes in RyR activity that disrupt normal Ca(2+) signaling. ⋯ These drugs show that the RyR is a valid therapeutic target, but have side effects that prevent their chronic use. Thus there is an urgent need for the development of skeletal and cardiac specific drugs to treat these diverse muscle disorders. In this review, we discuss the mutations that cause skeletal myopathies and cardiac arrhythmias and how these mutations pinpoint residues within the RyR protein that are functionally significant and might be developed as targets for therapeutic drugs.