Pharmacogenomics

Integrative Genomics of Emphysema-Associated Genes Reveals Potential Disease Biomarkers.

Fri, 2017-10-06 07:42
Related Articles

Integrative Genomics of Emphysema-Associated Genes Reveals Potential Disease Biomarkers.

Am J Respir Cell Mol Biol. 2017 Oct;57(4):411-418

Authors: Obeidat M, Nie Y, Fishbane N, Li X, Bossé Y, Joubert P, Nickle DC, Hao K, Postma DS, Timens W, Sze MA, Shannon CP, Hollander Z, Ng RT, McManus B, Miller BE, Rennard S, Spira A, Hackett TL, Lam W, Lam S, Faner R, Agusti A, Hogg JC, Sin DD, Paré PD

Abstract
Chronic obstructive pulmonary disease is the third leading cause of death worldwide. Gene expression profiling across multiple regions of the same lung identified genes significantly related to emphysema. We sought to determine whether the lung and epithelial expression of 127 emphysema-related genes was also related to lung function in independent cohorts, and whether any of these genes could be used as biomarkers in the peripheral blood of patients with chronic obstructive pulmonary disease. To that end, we examined whether the expression levels of these genes were under genetic control in lung tissue (n = 1,111). We then determined whether the mRNA levels of these genes in lung tissue (n = 727), small airway epithelial cells (n = 238), and peripheral blood (n = 620) were significantly related to lung function measurements. The expression of 63 of the 127 genes (50%) was under genetic control in lung tissue. The lung and epithelial mRNA expression of a subset of the emphysema-associated genes, including ASRGL1, LPHN2, and EDNRB, was strongly associated with lung function. In peripheral blood, the expression of 40 genes was significantly associated with lung function. Twenty-nine of these genes (73%) were also associated with lung function in lung tissue, but with the opposite direction of effect for 24 of the 29 genes, including those involved in hypoxia and B cell-related responses. The integrative genomics approach uncovered a significant overlap of emphysema genes associations with lung function between lung and blood with opposite directions between the two. These results support the use of peripheral blood to detect disease biomarkers.

PMID: 28459279 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

Klf10 Gene, a Secondary Modifier and a Pharmacogenomic Biomarker of Hydroxyurea Treatment Among Patients With Hemoglobinopathies.

Fri, 2017-10-06 07:42
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Klf10 Gene, a Secondary Modifier and a Pharmacogenomic Biomarker of Hydroxyurea Treatment Among Patients With Hemoglobinopathies.

J Pediatr Hematol Oncol. 2017 Apr;39(3):e155-e162

Authors: Elalfy MS, El Sherif NH, Kamal TM, Aly NH

Abstract
BACKGROUND: The klf10 gene could indirectly modify γ-globin chain production and hence the level of fetal hemoglobin (HbF) ameliorating the phenotype of β-hemoglobinopathies and the response to hydroxycarbamide (hydroxyurea [HU]) therapy. In this study, we aimed to evaluate the frequency of different genotypes for the klf10 gene in β-thalassemia major (B-TM), β-thalassemia intermedia (B-TI), and sickle cell disease (SCD) patients by polymerase chain reaction and to assess its relation to disease phenotypes and HU response.
METHODS: This cross-sectional study included 75 patients: 50 B-TM, 12 SCD, and 13 B-TI patients (on stable HU dose). The relation of the klf10 gene polymorphism (TIEG, TIEG1, EGRα) (rs3191333: c*0.141C>T) to phenotype was studied through baseline mean corpuscular volume, HbF, and transfusion history, whereas evaluation of response to HU therapy was carried out clinically and laboratory.
RESULTS: The frequency of the mutant klf10 genotype (TT) and that of the mutant allele (T) was significantly higher among B-TM patients compared with those with B-TI and SCD patients. Only homozygous SCD patients for the wild-type allele within the klf10 gene had a significantly lower transfusion frequency. The percentage of HU responders and nonresponders between different klf10 polymorphic genotypes among B-TI or SCD patients was comparable.
CONCLUSIONS: Although the klf10 gene does not play a standalone role as an HbF modifier, our data support its importance in ameliorating phenotype among β-hemoglobinopathies.

PMID: 28085748 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

pharmacogenomics; +15 new citations

Thu, 2017-10-05 10:17

15 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

pharmacogenomics

These pubmed results were generated on 2017/10/05

PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Categories: Literature Watch

pharmacogenomics; +15 new citations

Thu, 2017-10-05 06:01

15 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results:

pharmacogenomics

These pubmed results were generated on 2017/10/05

PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Categories: Literature Watch

Knowledge, Attitude, and Perceptions of Pharmacists and Pharmacy Students towards Pharmacogenomics in Zimbabwe.

Wed, 2017-10-04 09:49

Knowledge, Attitude, and Perceptions of Pharmacists and Pharmacy Students towards Pharmacogenomics in Zimbabwe.

Pharmacy (Basel). 2017 Jun 30;5(3):

Authors: Muzoriana N, Gavi S, Nembaware V, Dhoro M, Matimba A

Abstract
The potential of pharmacogenomics (PGx) to positively impact health outcomes and quality of healthcare is well-established. However, the application of available evidence into clinical practice is still limited due to limited knowledge among healthcare professionals, including pharmacists. As a start towards building capacity for PGx education, we assessed knowledge, attitudes, and perceptions about PGx among practising pharmacists and pharmacy students. A cross-sectional study was conducted among pharmacists and undergraduate pharmacy students selected using a convenient sampling method-a 37-question survey instrument was used to obtain information regarding PGx among the participants. Out of a total of 131 participants, 56% of respondents showed fair-to-good PGx knowledge. Respondents' self-reported assessment indicated that 88% had average and above knowledge scores in PGx. Practising pharmacists in Zimbabwe have positive attitudes towards PGx and would support its application to improve treatments. However, there were concerns about security and discrimination when genomics data is used by those who do not understand its meaning. Participants agreed that they would play a leading role in PGx testing if provided with appropriate training. The interest in PGx is challenged by their limited knowledge and understanding of genetics, suggesting a need to update curricula for pharmacy students and for continuing health education programmes.

PMID: 28970448 [PubMed]

Categories: Literature Watch

rs2841277 (PLD4) is associated with susceptibility and rs4672495 is associated with disease activity in rheumatoid arthritis.

Wed, 2017-10-04 09:49

rs2841277 (PLD4) is associated with susceptibility and rs4672495 is associated with disease activity in rheumatoid arthritis.

Oncotarget. 2017 Sep 08;8(38):64180-64190

Authors: Chen WC, Wang WC, Okada Y, Chang WP, Chou YH, Chang HH, Huang JD, Chen DY, Chang WC

Abstract
Rheumatoid arthritis (RA) is one of the most common autoimmune diseases, can lead to long-term joint damage, chronic pain, and loss of motor function in the hands, and may share some common genetic factors with other autoimmune disorders, such as ankylosing spondylitis (AS). Many single-nucleotide polymorphisms (SNPs) were reported by genome-wide association studies (GWASs) of RA, but some of them have not been examined in the Taiwanese population. In this study, for 15 SNPs reported in previous RA and AS GWASs, we investigated their association with RA in a Taiwanese population. Based on 334 RA patients recruited from the Taichung Veterans General Hospital and 16,036 healthy subjects from the Taiwan Biobank (TWB) project, we observed that subjects having minor allele C at rs2841277 (phospholipase D family, member 4 (PLD4)) have lower susceptibility of RA, compare to those having genotype TT (Odds ratio (OR) = 0.6, p = 3.0 × 10(-6)). Among the RA patients, we observed that subjects having GG at rs4672495 have a lower proportion of severe RA, compare to other subjects (OR = 0.09, p = 5.6 × 10(-3)). Results of a bioinformatics approach showed that rs2841277 is able to influence expression of LINC00638 and AHNAK2 and rs4672495 is able to influence the expression of B3GNT2. In summary, this study replicated an association of rs2841277 with RA susceptibility and showed an AS-associated SNP, rs4672495, is associated with RA activity in the Taiwanese population.

PMID: 28969061 [PubMed]

Categories: Literature Watch

Structural Basis of Single-Nucleotide Polymorphisms in Cytochrome P450 2C9.

Wed, 2017-10-04 06:47

Structural Basis of Single-Nucleotide Polymorphisms in Cytochrome P450 2C9.

Biochemistry. 2017 Oct 03;:

Authors: Maekawa K, Adachi M, Matsuzawa Y, Zhang Q, Kuroki R, Saito Y, Shah MB

Abstract
Single-nucleotide polymorphisms in drug-metabolizing cytochrome P450 (CYP) enzymes are important contributors to interindividual differences in drug metabolism leading to adverse drug reactions. Despite their extensive characterization and importance in pharmacogenetics of clinical drugs, the structural basis of CYP polymorphisms has remained scant. Here we report the crystal structures of human CYP2C9 and its polymorphic variants, *3 (I359L) and *30 (A477T), with an antihypertensive drug losartan. The structures show distinct interaction and occupation of losartan in the active site, the access channel, and the peripheral binding site. The I359L substitution located far from the active site remarkably altered the residue side chains near the active site and the access channel, whereas the T477 substitution illustrated hydrogen-bonding interaction with the reoriented side chain of Q214. The results yield structural insights into the reduced catalytic activity of the CYP2C9 variants and have important implications for understanding genetic polymorphisms in CYP-mediated drug metabolism.

PMID: 28972767 [PubMed - as supplied by publisher]

Categories: Literature Watch

Genetic variability of CYP2D6, CYP2B6, CYP2C9 and CYP2C19 genes across the Italian Peninsula.

Wed, 2017-10-04 06:47

Genetic variability of CYP2D6, CYP2B6, CYP2C9 and CYP2C19 genes across the Italian Peninsula.

Ann Hum Biol. 2017 Oct 03;:1-6

Authors: Carano F, Sarno S, De Fanti S, Serventi P, Bini C, Luiselli D, Pelotti S

Abstract
BACKGROUND: Environmental conditions and past migratory events may have shaped genetic heterogeneity of clinically relevant enzymes involved in the phase I metabolism of the most common therapeutic drugs.
AIM: To investigate the genetic variability of CYP2D6, CYP2B6, CYP2C19 and CYP2C9 across the Italian Peninsula, by sampling only ancestrally and geographically homogeneous individuals from northern, central and southern Italy.
SUBJECTS AND METHODS: A total of 25 SNPs were genotyped in 174 unrelated Italian individuals by means of multiplex PCR and minisequencing reactions. CYP2D6 genotypic data were used to predict phenotypes and the phylogenetic relationships among reconstructed haplotypes were represented by means of a Median Joining Network.
RESULTS: Pairwise Fisher Exact tests revealed significant differences between northern and southern Italy in the distribution of CYP2C19 genotypes, with the CYP2C19*2 allele appearing over-represented in northern Italy. Likewise, significant differences in the distribution of CYP2D6 genotypes (*4/*3, *4/*4 and *6/*4) responsible for the poor metabolizer phenotype were observed in northern with respect to both central and southern Italy.
CONCLUSIONS: The north-south structuring pattern showed by CYP2D6 and CYP2C19 underline how a deeper knowledge of the geographic distribution of alleles may improve clinical practice and help to avoid hypothetical bias in drug trials.

PMID: 28971704 [PubMed - as supplied by publisher]

Categories: Literature Watch

AGXT2: An unnegligible aminotransferase in cardiovascular and urinary systems.

Wed, 2017-10-04 06:47

AGXT2: An unnegligible aminotransferase in cardiovascular and urinary systems.

J Mol Cell Cardiol. 2017 Sep 29;:

Authors: Hu XL, Li MP, Song PY, Tang J, Chen XP

Abstract
Cardiovascular diseases (CVDs) and renal impairment interact in a complex and interdependent manner, which makes clarification of possible pathogenesis between CVDs and renal diseases very challenging and important. There is increasing evidence showing that both asymmetric dimethylarginine (ADMA) and symmetric dimethylarginine (SDMA) play a crucial role in the development of CVDs as well as in the prediction of cardiovascular events. Also, the plasma levels of ADMA and SDMA were reported to be significantly associated with renal function. Alanine-glyoxylate aminotransferase 2 (AGXT2) is reported to be involved in ADMA and SDMA metabolism, thus deficiency in the expression or activity of AGXT2 may play a part in the progression of cardiovascular or renal diseases through affecting ADMA/SDMA levels. Here, we focused our attention on AGXT2 and discussed its potential impact on CVDs and renal diseases. Meanwhile, the review also summarized the functions and recent advances of AGXT2, as well as the clinical association studies of AGXT2 in cardiovascular and urinary systems, which might arouse the interest of researchers in these fields.

PMID: 28970090 [PubMed - as supplied by publisher]

Categories: Literature Watch

Dopamine, the antipsychotic molecule: a perspective on mechanisms underlying antipsychotic response variability.

Wed, 2017-10-04 06:47

Dopamine, the antipsychotic molecule: a perspective on mechanisms underlying antipsychotic response variability.

Neurosci Biobehav Rev. 2017 Sep 29;:

Authors: Amato D, Vernon AC, Papaleo F

Abstract
All antipsychotics bind to the dopamine D2 receptor. An "optimal" level of D2 receptor blockade with antipsychotics is thought to ameliorate the positive symptoms of schizophrenia. However, persistent D2 receptor blockade is associated with a deteriorating clinical response in a subset of patients. Interestingly, antipsychotics with a weaker D2 receptor binding profile appear somewhat superior in this respect. This evidence challenges the hypothesis that D2 receptor blockade is the sole mechanism of antipsychotic efficacy and points to consistent inter-individual responses to antipsychotic treatment. Here, we hypothesize that clinically effective doses of antipsychotics would lead to the formation of a D2 receptor "reserve" that is likely composed of presynaptic dopamine D2 autoreceptors. The majority of the remaining postsynaptic dopamine receptors are instead occupied by antipsychotics. Endogenous dopamine would then mainly interact with this D2 autoreceptor reserve, thereby reducing the presynaptic synthesis and release of dopamine and resulting in an indirect antipsychotic effect. This new proposal reconciles conceptual and empirical gaps encountered when clinical outcomes are compared to the pharmacology of antipsychotics.

PMID: 28970021 [PubMed - as supplied by publisher]

Categories: Literature Watch

Genetic signatures in ischemic stroke: Focus on aspirin resistance.

Wed, 2017-10-04 06:47

Genetic signatures in ischemic stroke: Focus on aspirin resistance.

CNS Neurol Disord Drug Targets. 2017 Oct 02;:

Authors: Munshi A, Vasudeva K, Chaurasia P, Singh S

Abstract
Stroke is one of the leading causes of death. There has been compelling evidence that stroke has a genetic component. Genetic variants not only influence susceptibility to stroke but have also been found to alter the response to pharmacological agents and influence the clinical outcome of the disease. Stroke patients are treated with antiplatelet drugs like aspirin and clopidogrel to prevent a secondary stroke. Inspite the fact that many new antiplatelet drugs have been developed; aspirin is still considered as a golden standard for the antiplatelet therapy. Aspirin achieves its action by inhibiting platelet cyclooxygenase (COX) system involved in the formation of thromboxane A2 (TXA2). TXA2 triggers reactions leading to platelet activation and aggregation. This Non-steroidal anti-inflammatory drug (NSAID) acts by inhibiting this mediator. Despite the demonstrated benefits of aspirin, many patients develop secondary stroke or other vascular events, an observation that has led to the concept of aspirin resistance. Studies have demonstrated that adequate antiplatelet effects are not achieved in 5-45% patients suggesting that many individuals are aspirin resistant. Aspirin resistance is multifactorial in origin. A genetic component has also been suggested, and variants in more than a dozen genes involved in ADME and pharmacodynamics of aspirin have been shown to be responsible for aspirin resistance. In addition, the patients on aspirin treatment also face adverse drug reactions on account of genetic variation. The present review has been compiled with an aim to revisit all the studies related to genetic variation contributing to aspirin resistance as well as adverse drug reactions. The output of high throughput genomic technology like genome wide association studies and others has also been discussed.

PMID: 28969559 [PubMed - as supplied by publisher]

Categories: Literature Watch

Genetic variants influencing elevated myeloperoxidase levels increase risk of stroke.

Wed, 2017-10-04 06:47

Genetic variants influencing elevated myeloperoxidase levels increase risk of stroke.

Brain. 2017 Oct 01;140(10):2663-2672

Authors: Phuah CL, Dave T, Malik R, Raffeld MR, Ayres AM, Goldstein JN, Viswanathan A, Greenberg SM, Jagiella JM, Hansen BM, Norrving B, Jimenez-Conde J, Roquer J, Pichler A, Enzinger C, Montaner J, Fernandez-Cadenas I, Lindgren A, Slowik A, Schmidt R, Biffi A, Rost N, Langefeld CD, Markus HS, Mitchell BD, Worrall BB, Kittner SJ, Woo D, Dichgans M, Rosand J, Anderson CD, METASTROKE, NINDS-SiGN Consortium, International Stroke Genetics Consortium

Abstract
Primary intracerebral haemorrhage and lacunar ischaemic stroke are acute manifestations of progressive cerebral microvascular disease. Current paradigms suggest atherosclerosis is a chronic, dynamic, inflammatory condition precipitated in response to endothelial injury from various environmental challenges. Myeloperoxidase plays a central role in initiation and progression of vascular inflammation, but prior studies linking myeloperoxidase with stroke risk have been inconclusive. We hypothesized that genetic determinants of myeloperoxidase levels influence the development of vascular instability, leading to increased primary intracerebral haemorrhage and lacunar stroke risk. We used a discovery cohort of 1409 primary intracerebral haemorrhage cases and 1624 controls from three studies, an extension cohort of 12 577 ischaemic stroke cases and 25 643 controls from NINDS-SiGN, and a validation cohort of 10 307 ischaemic stroke cases and 29 326 controls from METASTROKE Consortium with genome-wide genotyping to test this hypothesis. A genetic risk score reflecting elevated myeloperoxidase levels was constructed from 15 common single nucleotide polymorphisms identified from prior genome-wide studies of circulating myeloperoxidase levels (P < 5 × 10-6). This genetic risk score was used as the independent variable in multivariable regression models for association with primary intracerebral haemorrhage and ischaemic stroke subtypes. We used fixed effects meta-analyses to pool estimates across studies. We also used Cox regression models in a prospective cohort of 174 primary intracerebral haemorrhage survivors for association with intracerebral haemorrhage recurrence. We present effects of myeloperoxidase elevating single nucleotide polymorphisms on stroke risk per risk allele, corresponding to a one allele increase in the myeloperoxidase increasing genetic risk score. Genetic determinants of elevated circulating myeloperoxidase levels were associated with both primary intracerebral haemorrhage risk (odds ratio, 1.07, P = 0.04) and recurrent intracerebral haemorrhage risk (hazards ratio, 1.45, P = 0.006). In analysis of ischaemic stroke subtypes, the myeloperoxidase increasing genetic risk score was strongly associated with lacunar subtype only (odds ratio, 1.05, P = 0.0012). These results, demonstrating that common genetic variants that increase myeloperoxidase levels increase risk of primary intracerebral haemorrhage and lacunar stroke, directly implicate the myeloperoxidase pathway in the pathogenesis of cerebral small vessel disease. Because genetic variants are not influenced by environmental exposures, these results provide new support for a causal rather than bystander role for myeloperoxidase in the progression of cerebrovascular disease. Furthermore, these results support a rationale for chronic inflammation as a potential modifiable stroke risk mechanism, and suggest that immune-targeted therapies could be useful for treatment and prevention of cerebrovascular disease.

PMID: 28969386 [PubMed - in process]

Categories: Literature Watch

The Pharmacogenomics of a Mutation 'Hotspot' for the Short QT Syndrome.

Tue, 2017-10-03 09:32

The Pharmacogenomics of a Mutation 'Hotspot' for the Short QT Syndrome.

JACC Clin Electrophysiol. 2017 Jul;3(7):744-746

Authors: Darbar D, McCauley M

PMID: 28966985 [PubMed]

Categories: Literature Watch

Time to revisit warfarin pharmacogenetics.

Tue, 2017-10-03 06:27

Time to revisit warfarin pharmacogenetics.

Future Cardiol. 2017 Oct 02;:

Authors: Cavallari LH

PMID: 28967279 [PubMed - as supplied by publisher]

Categories: Literature Watch

Severe Delayed Drug Reactions: Role of Genetics and Viral Infections.

Tue, 2017-10-03 06:27

Severe Delayed Drug Reactions: Role of Genetics and Viral Infections.

Immunol Allergy Clin North Am. 2017 Nov;37(4):785-815

Authors: Pavlos R, White KD, Wanjalla C, Mallal SA, Phillips EJ

Abstract
Adverse drug reactions (ADRs) are a significant source of patient morbidity and mortality and represent a major burden to health care systems and drug development. Up to 50% of such reactions are preventable. Although many ADRs can be predicted based on the on-target pharmacologic activity, ADRs arising from drug interactions with off-target receptors are recognized. Off-target ADRs include the immune-mediated ADRs (IM-ADRs) and pharmacologic drug effects. In this review, we discuss what is known about the immunogenetics and pathogenesis of IM-ADRs and the hypothesized role of heterologous immunity in the development of IM-ADRs.

PMID: 28965641 [PubMed - in process]

Categories: Literature Watch

Pharos: Collating protein information to shed light on the druggable genome.

Tue, 2017-10-03 06:27
Related Articles

Pharos: Collating protein information to shed light on the druggable genome.

Nucleic Acids Res. 2017 Jan 04;45(D1):D995-D1002

Authors: Nguyen DT, Mathias S, Bologa C, Brunak S, Fernandez N, Gaulton A, Hersey A, Holmes J, Jensen LJ, Karlsson A, Liu G, Ma'ayan A, Mandava G, Mani S, Mehta S, Overington J, Patel J, Rouillard AD, Schürer S, Sheils T, Simeonov A, Sklar LA, Southall N, Ursu O, Vidovic D, Waller A, Yang J, Jadhav A, Oprea TI, Guha R

Abstract
The 'druggable genome' encompasses several protein families, but only a subset of targets within them have attracted significant research attention and thus have information about them publicly available. The Illuminating the Druggable Genome (IDG) program was initiated in 2014, has the goal of developing experimental techniques and a Knowledge Management Center (KMC) that would collect and organize information about protein targets from four families, representing the most common druggable targets with an emphasis on understudied proteins. Here, we describe two resources developed by the KMC: the Target Central Resource Database (TCRD) which collates many heterogeneous gene/protein datasets and Pharos (https://pharos.nih.gov), a multimodal web interface that presents the data from TCRD. We briefly describe the types and sources of data considered by the KMC and then highlight features of the Pharos interface designed to enable intuitive access to the IDG knowledgebase. The aim of Pharos is to encourage 'serendipitous browsing', whereby related, relevant information is made easily discoverable. We conclude by describing two use cases that highlight the utility of Pharos and TCRD.

PMID: 27903890 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

Evaluation of a pharmacogenetic-based warfarin dosing algorithm in patients with low time in therapeutic range - study protocol for a randomized controlled trial.

Tue, 2017-10-03 06:27
Related Articles

Evaluation of a pharmacogenetic-based warfarin dosing algorithm in patients with low time in therapeutic range - study protocol for a randomized controlled trial.

BMC Cardiovasc Disord. 2016 Nov 17;16(1):224

Authors: Marcatto LR, Sacilotto L, Bueno CT, Facin M, Strunz CM, Darrieux FC, Scanavacca MI, Krieger JE, Pereira AC, Santos PC

Abstract
BACKGROUND: Time in therapeutic range (TTR) is a measurement of quality of warfarin therapy and lower TTR values (<50%) are associated with greater risk of thromboembolic and bleeding events. Recently, we developed a pharmacogenetic-based warfarin dosing algorithm specifically calibrated for a Brazilian patient sample. The aims of this study are: to evaluate the impact of a genetic-based algorithm, compared to traditional anticoagulation, in the time to achieve the therapeutic target and in TTR percentage; and to assess the cost-effectiveness of genotype-guided warfarin dosing in a specific cohort of patients with low TTR (<50%) from a tertiary cardiovascular hospital.
METHODS/DESIGN: This study is a randomized controlled trial in patients (n = 300) with atrial fibrillation with TTR < 50%, based on the last three INR values. At the first consultation, patients will be randomized into two groups: TA group (traditional anticoagulation) and PA group (pharmacogenetic anticoagulation). For the first group, the physician will adjust the dose according to current INR value and, for the second group, a pharmacogenetic algorithm will be used. At the second, third, fourth and fifth consultations (with an interval of 7 days each) INR will be measured and, if necessary, the dose will be adjusted based on guidelines. Afterwards, patients who are INR stable will begin measuring their INR in 30 day intervals; if the patient's INR is not stable, the patient will return in 7 days for a new measurement of the INR. Outcomes measures will include the time to achieve the therapeutic target and the percentage of TTR at 4 and 12 weeks. In addition, as a secondary end-point, pharmacoeconomic analysis will be carried out. Ethical approval was granted by the Ethics Committee for Medical Research on Human Beings of the Clinical Hospital of the University of São Paulo Medical School.
DISCUSSION: This randomized study will include patients with low TTR and it will evaluate whether a population-specific genetic algorithm might be more effective than traditional anticoagulation for a selected group of poorly anticoagulated patients.
TRIAL REGISTRATION: ClinicalTrials.gov, NCT02592980 . Registered on 29 October 2015.

PMID: 27855643 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

Clopidogrel High On-Treatment Platelet Reactivity in Patients with Carotid Artery Stenosis Undergoing Endarterectomy. A Pilot Study.

Tue, 2017-10-03 06:27
Related Articles

Clopidogrel High On-Treatment Platelet Reactivity in Patients with Carotid Artery Stenosis Undergoing Endarterectomy. A Pilot Study.

Curr Vasc Pharmacol. 2016;14(6):563-569

Authors: Backovic D, Ignjatovic S, Rakicevic L, Novkovic M, Kusic-Tisma J, Radojkovic D, Strugarevic E, Calija B, Radak D, Kovac M

Abstract
OBJECTIVES: A considerable number of patients do not achieve an adequate response to clopidogrel. Our study aimed to evaluate genetic and non-genetic factors as possible risks for clopidogrel high on-treatment platelet reactivity (HTPR) in patients (n=112) with carotid artery stenosis undergoing endarterectomy (CEA).
METHODS: Using multiple-electrode impedance aggregometry (MEA) the antiplatelet effectiveness of clopidogrel was measured after 24 h, 7 and 30 days of clopidogrel treatment, which was introduced after elective CEA at a dose of 75 mg daily, for at least 30 days.
RESULTS: HTPR was observed among 25% patients after clopidogrel therapy for 30 days. Further analysis showed that 53.3% of patients carrying the CYP2C19*2 gene variant had clopidogrel-HTPR, while in the wild type group there were 14.6% (p<0.001). Multivariate logistic regression analysis identified the CYP2C19*2 variant allele (OR 4.384; 95% CI 1.296-14.833, p=0.017) and high total cholesterol level (OR 2.090; 95% CI 1.263-3.459, p=0.004) as the only independent risk factors for clopidogrel-HTPR.
CONCLUSION: The CYP2C19*2 gene variant and high total cholesterol level were major factors for clopidogrel- HTPR in patients with carotid artery stenosis undergoing CEA.

PMID: 27411384 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

Effects of l-Tyrosine on working memory and inhibitory control are determined by DRD2 genotypes: A randomized controlled trial.

Tue, 2017-10-03 06:27
Related Articles

Effects of l-Tyrosine on working memory and inhibitory control are determined by DRD2 genotypes: A randomized controlled trial.

Cortex. 2016 Sep;82:217-224

Authors: Colzato LS, Steenbergen L, Sellaro R, Stock AK, Arning L, Beste C

Abstract
l-Tyrosine (TYR), the precursor of dopamine (DA), has been shown to enhance facets of cognitive control in situations with high cognitive demands. However some previous outcomes were mixed: some studies reported significant improvements, while other did not. Given that TYR increases DA level in the brain, we investigated, in a double-blind, randomized, placebo-controlled design, whether the C957T genotypes of a functional synonymous polymorphism in the human dopamine D2 receptor (DRD2) gene (rs6277) contribute to individual differences in the reactivity to TYR administration and whether this factor predicts the magnitude of TYR-induced performance differences on inhibiting behavioral responses in a stop-signal task and working memory (WM) updating in a N-back task. Our findings show that T/T homozygotes (i.e., individuals potentially associated with lower striatal DA level) showed larger beneficial effects of TYR supplementation than C/C homozygotes (i.e., individuals potentially associated with higher striatal DA level), suggesting that genetically determined differences in DA function may explain inter-individual differences in response to TYR supplementation. These findings reinforce the idea that genetic predisposition modulates the effect of TYR in its role as cognitive enhancer.

PMID: 27403851 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

Challenges in preclinical to clinical translation for anticancer carrier-mediated agents.

Tue, 2017-10-03 06:27
Related Articles

Challenges in preclinical to clinical translation for anticancer carrier-mediated agents.

Wiley Interdiscip Rev Nanomed Nanobiotechnol. 2016 Sep;8(5):642-53

Authors: Lucas AT, Madden AJ, Zamboni WC

Abstract
Major advances in carrier-mediated agents (CMAs), which include nanoparticles and conjugates, have revolutionized drug delivery capabilities over the past decade. While providing numerous advantages over their small-molecule counterparts, there is substantial variability in how individual CMA formulations and patient characteristics affect the pharmacology, pharmacokinetics (PK), and pharmacodynamics (PD) (efficacy and toxicity) of these agents. Development or selection of animal models is used to predict the effects within a particular human disease. A breadth of studies have begun to emphasize the importance of preclinical animal models in understanding and evaluating the interaction between CMAs and the immune system and tumor matrix, which ultimately influences CMA PK (clearance and distribution) and PD (efficacy and toxicity). It is fundamental to study representative preclinical tumor models that recapitulate patients with diseases (e.g., cancer) and evaluate the interplay between CMAs and the immune system, including the mononuclear phagocyte system (MPS), chemokines, hormones, and other immune modulators. Furthermore, standard allometric scaling using body weight does not accurately predict drug clearance in humans. Future studies are warranted to better understand the complex pharmacology and interaction of CMA carriers within individual preclinical models and their biological systems, such as the MPS and tumor microenvironment, and their application to allometric scaling across species. WIREs Nanomed Nanobiotechnol 2016, 8:642-653. doi: 10.1002/wnan.1394 For further resources related to this article, please visit the WIREs website.

PMID: 26846457 [PubMed - indexed for MEDLINE]

Categories: Literature Watch

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