Prognostic significance of peritoneal cytology in low-intermediate risk endometrial cancer.

OBJECTIVES: There is uncertainty surrounding the prognostic value and clinical utility of peritoneal cytology in endometrial cancer. Our primary objective was to determine if positive cytology is associated with disease-free and overall survival in women treated surgically for endometrial cancer, specifically those with low or intermediate risk disease. METHODS: This was a retrospective population-based cohort study of British Columbia Cancer Registry patients who underwent surgery with peritoneal washings for endometrioid-type endometrial cancer from 2003 to 2009. Low risk was defined as Stage IA grade 1 or 2, and intermediate risk defined as Stage IA grade 3, or Stage IB grade 1 or 2 tumours. Five-year overall and disease free-survival were assessed using Kaplan-Meier estimation. Potential covariates including peritoneal cytology, grade, depth of myometrial invasion, LVSI, age, and adjuvant therapy were evaluated in a multivariable Cox proportional hazards model. RESULTS: There were 849 patients, of whom 370 (43.6%) and 298 (35.1%) had low- and intermediate-risk disease, respectively. Overall, forty-nine (5.8%) patients had positive cytology, including 6 and 9 with low- and intermediate-risk respectively (2.2% within low and intermediate risk combined). Positive peritoneal cytology was not significantly associated with disease-free (HR 3.17, 95% CI 0.91-11.03) or overall survival (HR 1.33, 95% CI 0.47-3.76) in low and intermediate risk patients. Only age and extensive LVSI were associated with lower overall survival (HR 1.10, 95% CI 1.08-1.13, and HR 2.39, 95% CI 1.02-5.61, respectively). CONCLUSIONS: Positive peritoneal cytology was not associated with disease-free and overall survival in women with low and intermediate risk endometrial cancer.

Multi-ethnic distribution of clinically relevant CYP2C genotypes and haplotypes.

To determine CYP2C19 and CYP2C8 allele frequencies, 28 coding and/or functional variants were genotyped in 1250 African-American, Asian, Caucasian, Hispanic and Ashkenazi Jewish (AJ) individuals. The combined CYP2C19 variant allele frequencies ranged from ∼0.30 to 0.41; however, the CYP2C8 frequencies were much lower (∼0.04-0.13). After incorporating previously reported CYP2C9 genotyping results from these populations (36 total CYP2C variants), 16 multi-ethnic CYP2C haplotypes were inferred with frequencies >0.5%. Notably, the 2C19*17-2C9*1-2C8*2 haplotype was identified among African-Americans (8%) and Hispanics (2%), indicating that CYP2C19*17 does not always tag a CYP2C haplotype that encodes efficient CYP2C-substrate metabolism. The 2C19*1-2C9*2-2C8*3 haplotype was identified in all populations except African-Americans and additional novel haplotypes were identified in selected populations (for example, 2C19*2-2C9*1-2C8*4 and 2C19*4B-2C9*1-2C8*1), together indicating that both CYP2C19*17 and *2 can be linked with other CYP2C loss-of-function alleles. These results have important implications for pharmacogenomic association studies involving the CYP2C locus and are clinically relevant when administering CYP2C-substrate medications.

Multi-ethnic cytochrome-P450 copy number profiling: novel pharmacogenetic alleles and mechanism of copy number variation formation.

To determine the role of CYP450 copy number variation (CNV) beyond CYP2D6, 11 CYP450 genes were interrogated by multiplex ligation-dependent probe amplification and quantitative PCR in 542 African-American, Asian, Caucasian, Hispanic and Ashkenazi Jewish individuals. The CYP2A6, CYP2B6 and CYP2E1 combined deletion/duplication allele frequencies ranged from 2 to 10% in these populations. High-resolution microarray-based comparative genomic hybridization (aCGH) localized CYP2A6, CYP2B6 and CYP2E1 breakpoints to directly oriented low-copy repeats. Sequencing localized the CYP2B6 breakpoint to a 529-bp intron 4 region with high homology to CYP2B7P1, resulting in the CYP2B6*29 partial deletion allele and the reciprocal, and novel, CYP2B6/2B7P1 duplicated fusion allele (CYP2B6*30). Together, these data identified novel CYP450 CNV alleles (CYP2B6*30 and CYP2E1*1Cx2) and indicate that common CYP450 CNV formation is likely mediated by non-allelic homologous recombination resulting in both full gene and gene-fusion copy number imbalances. Detection of these CNVs should be considered when interrogating these genes for pharmacogenetic drug selection and dosing.

Identification of CYP2C19*4B: pharmacogenetic implications for drug metabolism including clopidogrel responsiveness.

CYP2C19 is a principal enzyme involved in the bioactivation of the antiplatelet prodrug clopidogrel and common CYP2C19 loss-of-function alleles are associated with adverse cardiovascular events. To assess the impact of the CYP2C19*17 increased activity allele in the Ashkenazi Jewish (AJ) and Sephardi Jewish (SJ) populations and to determine the frequencies of additional variant alleles, 250 AJ and 135 SJ individuals were genotyped for CYP2C19*2-*10, *12-*17, *22 and P-glycoprotein (ABCB1) c.3435C>T. Importantly, CYP2C19*4, a loss-of-function allele, was identified in linkage disequilibrium with *17. This novel haplotype, designated CYP2C19*4B, significantly alters the interpretation of CYP2C19 genotyping when testing *17. Moreover, genotyping CYP2C19*17 changed the frequency of extensive metabolizers from ∼70 to ∼40%, reclassifying ∼30% as ultrarapid metabolizers. Combining CYP2C19 and ABCB1 identified ∼1 in 3 AJ and ∼1 in 2 SJ individuals at increased risk for adverse responses to clopidogrel. These data underscore the importance of including *4B and *17 when clinically genotyping CYP2C19.

Fractal electronic devices: simulation and implementation.

Many natural structures have fractal geometries that exhibit useful functional properties. These properties, which exploit the recurrence of patterns at increasingly small scales, are often desirable in applications and, consequently, fractal geometry is increasingly employed in diverse technologies ranging from radio antennae to storm barriers. In this paper, we explore the application of fractal geometry to electrical devices. First, we lay the foundations for the implementation of fractal devices by considering diffusion-limited aggregation (DLA) of atomic clusters. Under appropriate growth conditions, atomic clusters of various elements form fractal patterns driven by DLA. We perform a fractal analysis of both simulated and physical devices to determine their spatial scaling properties and demonstrate their potential as fractal circuit elements. Finally, we simulate conduction through idealized and DLA fractal devices and show that their fractal scaling properties generate novel, nonlinear conduction properties in response to depletion by electrostatic gates.

Quantitative determination of contributions to the thermoelectric power factor in Si nanostructures.

We report thermoelectric measurements on a silicon nanoribbon in which an integrated gate provides strong carrier confinement and enables tunability of the carrier density over a wide range. We find a significantly enhanced thermoelectric power factor that can be understood by considering its behavior as a function of carrier density. We identify the underlying mechanisms for the power factor in the nanoribbon, which include quantum confinement, low scattering due to the absence of dopants, and, at low temperatures, a significant phonon-drag contribution. The measurements set a target for what may be achievable in ultrathin nanowires.

Persistence of foreign innervation on reinnervated goldfish extraocular muscles.

Behavioral observations have suggested that the function of foreign synapses on goldfish extraocular muscles can be repressed after reinnervation by the original nerve without any ultrastructural alterations. The present experiments demonstrate that even after behavioral repression foreign synapses are physiologically functionl and that the original and foreign nerves can simultaneously innervate goldfish extraocular muscles.

Correct axonal regeneration after target cell removal in the central nervous system of the leech.

The unique target neuron of a severed axon in the leech was selectively eliminated by intracellular injection of protease. In the absence of the target, the severed axon regenerated normally along its original pathway to the usual site of synapse, where it stopped growing without forming alternative connections.

Tuberculosis infection control in a South African rural regional hospital emergency centre: Prioritisation for patients and healthcare workers.

South Africa (SA) is in the midst of a tuberculosis (TB) epidemic and has one of the highest TB incidence rates globally. Despite increasing global commitment to eliminate TB, SA appears to be falling behind in this regard. This article examines key challenges to effective TB infection control from a rural regional hospital perspective. It uses the Eden District in Western Cape Province as an example to share lessons learnt. This quality-improvement project identifies four priorities for improving TB infection control in George Hospital and the Eden District: (i) prioritising TB infection control in local policy; (ii) improving the quality of TB screening in the emergency centre; (iii) increasing the number of TB patients followed up; and (iv) implementing TB infection control training for all staff. This project demonstrates the role of an emergency centre in TB screening, highlighting that this should not only be a priority for primary care, but also for secondary and tertiary care. Simple interventions, such as training of local healthcare workers in TB infection control and good-quality TB screening, can initiate a behavioural change. It also stresses the importance of good communication and co-ordination of care across primary and secondary care, ensuring that patients are not lost to follow-up. Local policy needs to reflect these straightforward interventions, empowering local healthcare workers and managers to increase responsibility and accountability for TB infection control.TB is preventable, and infection control needs to become a priority throughout SA primary, secondary and tertiary care. This project highlights that simple interventions, such as engaging local healthcare workers in a co-ordinated multisystem and multidisciplinary approach, could help to reduce the number of missing TB cases and bring SA's TB epidemic under control.

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guidelines for CYP2C19 and Voriconazole Therapy.

Voriconazole, a triazole antifungal agent, demonstrates wide interpatient variability in serum concentrations, due in part to variant CYP2C19 alleles. Individuals who are CYP2C19 ultrarapid metabolizers have decreased trough voriconazole concentrations, delaying achievement of target blood concentrations; whereas poor metabolizers have increased trough concentrations and are at increased risk of adverse drug events. We summarize evidence from the literature supporting this association and provide therapeutic recommendations for the use of voriconazole for treatment based on CYP2C19 genotype (updates at https://cpicpgx.org/guidelines/ and www.pharmgkb.org).

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for Pharmacogenetics-Guided Warfarin Dosing: 2017 Update.

This document is an update to the 2011 Clinical Pharmacogenetics Implementation Consortium (CPIC) guideline for CYP2C9 and VKORC1 genotypes and warfarin dosing. Evidence from the published literature is presented for CYP2C9, VKORC1, CYP4F2, and rs12777823 genotype-guided warfarin dosing to achieve a target international normalized ratio of 2-3 when clinical genotype results are available. In addition, this updated guideline incorporates recommendations for adult and pediatric patients that are specific to continental ancestry.

Cathepsin D-mediated proteolysis of apolipoprotein E: possible role in Alzheimer's disease.

Proteolysis of apolipoprotein E (apoE) may be involved in the pathogenesis of Alzheimer's disease (AD). We previously identified aspartic protease(s) as possibly contributing to the proteolysis of apoE in human brain homogenates. The current study used biochemical and immunohistochemical methods to examine whether cathepsin D (catD) and cathepsin E (catE), candidate aspartic proteases, may be involved in apoE proteolysis. CatD was found to proteolyze both lipid-free recombinant full-length human apoE and lipidated human plasma full-length apoE (apoE4/dipalmitoylphosphatidylcholine-reconstituted discs). CatE was found to proteolyze lipid-free recombinant human apoE to a much greater extent than lipidated apoE. This proteolysis, as well as proteolysis of human apoE added to brain homogenates from apoE-deficient mice, was inhibited by pepstatin A (an aspartic protease inhibitor), but not by phenylmethanesulfonyl fluoride (a serine protease inhibitor). The major apoE fragment obtained with catD included the receptor-binding domain and had an apparent molecular weight similar to that found in human brain homogenates. There was little immunoreactivity for catE in AD brain tissue sections. In contrast, qualitative and quantitative analyses of immunostained sections of the frontal cortex revealed that catD and apoE are colocalized in a subset of predominantly dense-core neuritic plaques and in some neurofibrillary tangles. A positive correlation was observed between estimated duration of illness and the percentage of apoE-positive plaques that were also catD-positive. These results suggest that aspartic proteases, catD in particular, may be involved in proteolysis of apoE and perhaps contribute to the generation of apoE fragments previously implicated in AD pathology.

Implementing Algorithm-Guided Warfarin Dosing in an Ethnically Diverse Patient Population Using Electronic Health Records and Preemptive CYP2C9 and VKORC1 Genetic Testing.

Implementation of pharmacogenetic-guided warfarin dosing has been hindered by inconsistent results from reported clinical trials and a lack of available algorithms that include alleles prevalent in non-white populations. However, current evidence indicates that algorithm-guided dosing is more accurate than empirical dosing. To facilitate multiethnic algorithm-guided warfarin dosing using preemptive genetic testing, we developed a strategy that accounts for the complexity of race and leverages electronic health records for algorithm variables and deploying point-of-care dose recommendations.

Capturing Structural Dynamics in Crystalline Silicon Using Chirped Electrons from a Laser Wakefield Accelerator.

Recent progress in laser wakefield acceleration has led to the emergence of a new generation of electron and X-ray sources that may have enormous benefits for ultrafast science. These novel sources promise to become indispensable tools for the investigation of structural dynamics on the femtosecond time scale, with spatial resolution on the atomic scale. Here, we demonstrate the use of laser-wakefield-accelerated electron bunches for time-resolved electron diffraction measurements of the structural dynamics of single-crystal silicon nano-membranes pumped by an ultrafast laser pulse. In our proof-of-concept study, we resolve the silicon lattice dynamics on a picosecond time scale by deflecting the momentum-time correlated electrons in the diffraction peaks with a static magnetic field to obtain the time-dependent diffraction efficiency. Further improvements may lead to femtosecond temporal resolution, with negligible pump-probe jitter being possible with future laser-wakefield-accelerator ultrafast-electron-diffraction schemes.

Exome sequencing of extreme clopidogrel response phenotypes identifies B4GALT2 as a determinant of on-treatment platelet reactivity.

Interindividual variability in platelet aggregation is common among patients treated with clopidogrel and both high on-treatment platelet reactivity (HTPR) and low on-treatment platelet reactivity (LTPR) increase risks for adverse clinical outcomes. CYP2C19 influences clopidogrel response but only accounts for ∼12% of the variability in platelet reactivity. To identify novel variants implicated in on-treatment platelet reactivity, patients with coronary artery disease (CAD) with extreme pharmacodynamic responses to clopidogrel and wild-type CYP2C19 were subjected to exome sequencing. Candidate variants that clustered in the LTPR subgroup subsequently were genotyped across the discovery cohort (n = 636). Importantly, carriers of B4GALT2 c.909C>T had lower on-treatment P2Y12 reaction units (PRUs; P = 0.0077) and residual platelet aggregation (P = 0.0008) compared with noncarriers, which remained significant after adjusting for CYP2C19 and other clinical variables in both the discovery (P = 0.0298) and replication (n = 160; PRU: P = 0.0001) cohorts. B4GALT2 is a platelet-expressed galactosyltransferase, indicating that B4GALT2 c.909C>T may influence clopidogrel sensitivity through atypical cell-surface glycoprotein processing and platelet adhesion.

Pharmacogenetic allele nomenclature: International workgroup recommendations for test result reporting.

This article provides nomenclature recommendations developed by an international workgroup to increase transparency and standardization of pharmacogenetic (PGx) result reporting. Presently, sequence variants identified by PGx tests are described using different nomenclature systems. In addition, PGx analysis may detect different sets of variants for each gene, which can affect interpretation of results. This practice has caused confusion and may thereby impede the adoption of clinical PGx testing. Standardization is critical to move PGx forward.

Genetic variation among 82 pharmacogenes: The PGRNseq data from the eMERGE network.

Genetic variation can affect drug response in multiple ways, although it remains unclear how rare genetic variants affect drug response. The electronic Medical Records and Genomics (eMERGE) Network, collaborating with the Pharmacogenomics Research Network, began eMERGE-PGx, a targeted sequencing study to assess genetic variation in 82 pharmacogenes critical for implementation of "precision medicine." The February 2015 eMERGE-PGx data release includes sequence-derived data from ∼5,000 clinical subjects. We present the variant frequency spectrum categorized by variant type, ancestry, and predicted function. We found 95.12% of genes have variants with a scaled Combined Annotation-Dependent Depletion score above 20, and 96.19% of all samples had one or more Clinical Pharmacogenetics Implementation Consortium Level A actionable variants. These data highlight the distribution and scope of genetic variation in relevant pharmacogenes, identifying challenges associated with implementing clinical sequencing for drug treatment at a broader level, underscoring the importance for multifaceted research in the execution of precision medicine.

Clinical Pharmacogenetics Implementation Consortium (CPIC) Guideline for CYP2D6 and CYP2C19 Genotypes and Dosing of Selective Serotonin Reuptake Inhibitors.

Selective serotonin reuptake inhibitors (SSRIs) are primary treatment options for major depressive and anxiety disorders. CYP2D6 and CYP2C19 polymorphisms can influence the metabolism of SSRIs, thereby affecting drug efficacy and safety. We summarize evidence from the published literature supporting these associations and provide dosing recommendations for fluvoxamine, paroxetine, citalopram, escitalopram, and sertraline based on CYP2D6 and/or CYP2C19 genotype (updates at www.pharmgkb.org).

Increased NGF-like activity in young but not aged rat hippocampus after septal lesions.

Sympathetic sprouting in the hippocampus following septal denervation is thought to involve nerve growth factor (NGF). This sprouting response is dramatically reduced in aged rats, but immunological assays reveal no age-related decline in hippocampal NGF levels. In the present study, both a bioassay and an immunoassay were used to examine the effect of a medial septal lesion on hippocampal NGF levels in young adult (2-5 months) and aged (24 months) Fischer 344 rats. No significant differences were detected between normal young and aged rats, in agreement with earlier results. Following medial septal lesions, however, only young rats demonstrated significant increases in hippocampal NGF-like activity. These results support the hypothesis that the age-related deficit in sympathetic sprouting results from an attenuated neurotrophic response to hippocampal denervation.