EFFECTS OF ISOFORM-SELECTIVE PHOSPHATIDYLINOSITOL-3 KINASE INHIBITORS ON OSTEOCLASTS

Phosphatidylinositol 3-kinases (PI3K) are key intracellular signaling molecules. Our objective was to determine effects of isoform-selective PI3K inhibitors on osteoclasts. The following inhibitors were investigated (targets in parentheses): wortmannin and LY294002 (pan-pllO), PIK75 (a), GDC0941 (a, 5), TGX221 (p), AS252424 (y), IC87114 (5) and CAL-120 (5). Wortmannin, GDC0941, IC87114 and CAL-120 induced dramatic retraction of rat osteoclasts. In contrast, there was no significant retraction in response to vehicle, PIK75, TGX221 or AS252424. Moreover, wortmannin and CAL- 120, but not PIK75 or TGX221, disrupted filamentous F-actin belts; and CAL-120 inhibited the formation of sealing zones. In contrast to their selective actions on cytoskeletal organization, PIK75, TGX221 and CAL-120 blocked RANKL-stimulated osteoclast survival. Thus, PI3K8 appears to play a specific role in regulating osteoclast cytoskeleton. In contrast, multiple PI3K isoforms control osteoclast survival. The PI3K5 isoform, which has more limited tissue distribution than PI3Ka and PI3KP, is an attractive target for anti-resorptive therapeutic

Functional Antimicrobial Surfaces by Ultrafine Powder Coating

The modem era of technology has amplified the significance of coated materials as well as their potential relevance and opportunity. With microbial infection arising as one of North America’s biggest public concerns, by the ongoing spread o f harmful microorganisms, the need for a marketably simple and durable antimicrobial surface has arisen for applications including inanimate objects and/or biomaterials. Antimicrobial surfaces cater to public safety by protection/prevention of infectious disease by the reduction of transmission of harmful microorganisms and the intervention of microorganism contamination. This study exhibits the development of various powder coating formulation efficacies against Escherichia coli and corresponding bacterial reductions of over 99% after only hours of exposure on metallic substrates. The most effective formulations recognize differences in the inorganic active agent concentrations of silver ion or nano silver metal and accompanied additive percentages of corresponding carrier materials of natural chabazite zeolite or silica gel. As an additional advantage to functional antimicrobial coatings, ultrafine powder coating is an environmentally friendly green technological coating, since it eliminates the use of toxic solvents that are responsible for the hazardous emissions of volatile organic compound

The Two Worlds of University Publishing

24 p. 23 cm. "Given on November 16, 1967, under the joint sponsorship of the University of Kansas Libraries and of the University Press of Kansas, on the occasion of the founding of the new press." Bibliography: p. 24

Sustainable management of Central Victorian mineral waters

Central Victoria contains more than 100 carbonated mineral water springs, many were discovered when uncovered by alluvial gold mining activities of the 1850's. The mineral springs are located at distances of 2 to 45 km from the crest of the Great Dividing Range, and are situated at elevations from 700 down to 200 m above sea level. The discharge from individual springs is small, and usually falls in the range 0.01 0.4 L/s (0.3-13 ML/annum). The mineral spring waters are cold ranging from around 10o C at the higher elevations to 17o C at the springs occurring at lower elevations. The carbonated mineral waters are a facies of the more widely distributed high bicarbonate alkalinity groundwater in the deep circulation systems of Central Victoria. The carbonated mineral waters are mildly acidic (pH 5.7 - 6.3), oxidic (Eh +50 to +100 mv), have low chloride (median 60 mg/L), high bicarbonate (median 1500 mg/L) and low sulphate (median 18 mg/L) concentrations. The water becomes slightly effervescent on discharge from the springs, and may be vigorously gassy when escaping from bores in the ascension zone. The characteristics of the mineral water chemistry may be explained by clay reactions - proton exchange, carbonate dissolution and base exchange. In the ascension zone heterogeneous thermodynamics, including the dissociation characteristics of a diprotic acid, acidity regulation by non carbonate equilibria, in particular by iron chemistry results in effervescence as pressure, degassing, acidity change and electro neutrality determine the water chemistry. Local characterisation of the m ineral waters arises from a superimposition of flux and mixing relationships encountered in discharge or ascension zones on regional trends. In Central Victoria the bedrock aquifer consists of interbedded lithic and arkosic grits, sandstones and graphitic shales. The most common occurrence is in rocks of Lower Ordovician age, but mineral waters also occur in Cambrian, Upper Silurian and Lower Devonian strata. The rocks have been subjected to variable but low grade regional metamorphism. Sandstone and grit units may retain some primary porosity, and thin intersections of unconsolidated sediment occur in bore holes. Narrow bands of saccharoidal marble and cone-in-cone limestone are present, but carbonates are a minor constituent of the rock mass (0.5% - 2%) and associated diagenetic ankerite. Organic carbon may exceed 5% in the black graphitic shales. Deep weathering profiles are developed on these rocks with elution of carbonates and kaolinisation silicate minerals. The rocks are folded asymmetrically and cut by strongly developed concordant meridional bearing thrust faults. The linear character of the rock mass failure produces anisotropy and heterogeneity. Deep fissure flow systems emanating from the Great Dividing Range follow litho structural corridors for distances of more than 40 km and groundwater has been observed in the bedrock mines of Central Victoria at depths of more than 1.6 km. The sustainable management of the mineral water resource involves the maintenance of yield, water quality and public equity. Sustaining Public Equity was initiated in 1865 by the formal establishment of mineral spring reserves. Reserves were proclaimed to preserve the springs from "the ravages of mining, and for public recreation and amusement". At Hepburn the first Pavilion was erected in 1869; a bottling plant in 1880 and a bath house was built in 1890. The region is the centre of balneology and hydrotherapy in Victoria and provides a 150 year history of development, conflict and sustainable resource management resolution. The spring reserves and surrounding buffer areas in the planning schemes offer protection for the discharge zones, but there is increasing tendency to commercialise and encroach on the reserves and allocate the mineral water for commercial or semi commercial development. Past evidence illustrates that management of the water quality, its salinity and gas content, is equally difficu lt as the maintenance of the flow of the springs and the continuation of public equity. Long term sustainable management is an evolving process that recognises past failures and crises. It shares the failure profile exhibited in many examples of overseas development of mineral and thermal waters. Legal Principles and endeavours outside the jurisdiction of the water and environment protection sectors are pre-eminent in the decision making processes. Nevertheless, the existing regulatory processes do have the potential to protect the resource

Neurohormonal Regulation of IKs in Heart Failure: Implications for Ventricular Arrhythmogenesis and Sudden Cardiac Death

Heart failure (HF) results in sustained alterations in neurohormonal signaling, including enhanced signaling through the sympathetic nervous system and renin-angiotensin-aldosterone system pathways. While enhanced sympathetic nervous system and renin-angiotensin-aldosterone system activity initially help compensate for the failing myocardium, sustained signaling through these pathways ultimately contributes to HF pathophysiology. HF remains a leading cause of mortality, with arrhythmogenic sudden cardiac death comprising a common mechanism of HF-related death. The propensity for arrhythmia development in HF occurs secondary to cardiac electrical remodeling that involves pathological regulation of ventricular ion channels, including the slow component of the delayed rectifier potassium current, that contribute to action potential duration prolongation. To elucidate a mechanistic explanation for how HF-mediated electrical remodeling predisposes to arrhythmia development, a multitude of investigations have investigated the specific regulatory effects of HF-associated stimuli, including enhanced sympathetic nervous system and renin-angiotensin-aldosterone system signaling, on the slow component of the delayed rectifier potassium current. The objective of this review is to summarize the current knowledge related to the regulation of the slow component of the delayed rectifier potassium current in response to HF-associated stimuli, including the intracellular pathways involved and the specific regulatory mechanisms

Calcium/Calmodulin-Dependent Protein Kinase II Regulation of IKs during Sustained Beta-Adrenergic Receptor Stimulation

Background Sustained β-adrenergic receptor (β-AR) stimulation causes pathophysiological changes during heart failure (HF), including inhibition of the slow component of the delayed rectifier potassium current (IKs). Aberrant calcium handling, including increased activation of calcium/calmodulin-dependent protein kinase II (CaMKII), contributes to arrhythmia development during HF. Objective The purpose of this study was to investigate CaMKII regulation of KCNQ1 (pore-forming subunit of IKs) during sustained β-AR stimulation and associated functional implications on IKs. Methods KCNQ1 phosphorylation was assessed using LCMS/MS after sustained β-AR stimulation with isoproterenol (ISO). Peptide fragments corresponding to KCNQ1 residues were synthesized to identify CaMKII phosphorylation at the identified sites. Dephosphorylated (alanine) and phosphorylated (aspartic acid) mimics were introduced at identified residues. Whole-cell, voltage-clamp experiments were performed in human endothelial kidney 293 cells coexpressing wild-type or mutant KCNQ1 and KCNE1 (auxiliary subunit) during ISO treatment or lentiviral δCaMKII overexpression. Results Novel KCNQ1 carboxy-terminal sites were identified with enhanced phosphorylation during sustained β-AR stimulation at T482 and S484. S484 peptides demonstrated the strongest δCaMKII phosphorylation. Sustained β-AR stimulation reduced IKs activation (P = .02 vs control) similar to the phosphorylated mimic (P = .62 vs sustained β-AR). Individual phosphorylated mimics at S484 (P = .04) but not at T482 (P = .17) reduced IKs function. Treatment with CN21 (CaMKII inhibitor) reversed the reductions in IKs vs CN21-Alanine control (P < .01). δCaMKII overexpression reduced IKs similar to ISO treatment in wild type (P < .01) but not in the dephosphorylated S484 mimic (P = .99). Conclusion CaMKII regulates KCNQ1 at S484 during sustained β-AR stimulation to inhibit IKs. The ability of CaMKII to inhibit IKs may contribute to arrhythmogenicity during HF

Efavirenz inhibits the human ether-a-go-go related current (hERG) and induces QT interval prolongation in CYP2B6*6*6 allele carriers

Background Efavirenz (EFV) has been associated with torsade de pointes despite marginal QT interval lengthening. Since EFV is metabolized by the cytochrome P450 (CYP) 2B6 enzyme, we hypothesized that EFV would lengthen the rate-corrected QT (QTcF) interval in carriers of the CYP2B6*6 decreased functional allele. Objective The primary objective of this study was to evaluate EFV-associated QT interval changes with regard to CYP2B6 genotype and to explore mechanisms of QT interval lengthening. Methods EFV was administered to healthy volunteers (n=57) as a single 600 mg dose followed by multiple doses to steady-state. Subjects were genotyped for known CYP2B6 alleles and ECGs and EFV plasma concentrations were obtained serially. Whole-cell, voltage-clamp experiments were performed on cells stably expressing hERG and exposed to EFV in the presence and absence of CYP2B6 expression. Results EFV demonstrated a gene-dose effect and exceeded the FDA criteria for QTcF interval prolongation in CYP2B6*6/*6 carriers. The largest mean time-matched differences ΔΔQTcF were observed at 6 hrs (14 ms; 95% CI [1; 27]), 12 hrs (18 ms; 95% CI [−4; 40] and 18 hrs (6 ms; 95% CI [−1; 14]) in the CYP2B6*6/*6 genotype. EFV concentrations exceeding 0.4 µg/mL significantly inhibited outward hERG tail currents (P<0.05). Conclusions This study demonstrates that homozygous carriers of CYP2B6*6 allele may be at increased risk for EFV-induced QTcF interval prolongation via inhibition of hERG

Life-Threatening Docetaxel Toxicity in a Patient With Reduced-Function CYP3A Variants: A Case Report.

Docetaxel therapy occasionally causes severe and life-threatening toxicities. Some docetaxel toxicities are related to exposure, and inter-individual variability in exposure has been described based on genetic variation and drug-drug interactions that impact docetaxel clearance. Cytochrome P450 3A4 (CYP3A4) and CYP3A5 metabolize docetaxel into inactive metabolites, and this is the primary mode of docetaxel clearance. Supporting their role in these toxicities, increased docetaxel toxicities have been found in patients with reduced- or loss-of-function variants in CYP3A4 and CYP3A5. However, since these variants in CYP3A4 are rare, little is known about the safety of docetaxel in patients who are homozygous for the reduced-function CYP3A4 variants. Here we present a case of life-threatening (grade 4) pneumonitis, dyspnea, and neutropenia resulting from a single dose of docetaxel. This patient was (1) homozygous for CYP3A4*22, which causes reduced expression and is associated with increased docetaxel-related adverse events, (2) heterozygous for CYP3A4*3, a rare reduced-function missense variant, and (3) homozygous for CYP3A5*3, a common loss of function splicing defect that has been associated with increased docetaxel exposure and adverse events. The patient also carried functional variants in other genes involved in docetaxel pharmacokinetics that may have increased his risk of toxicity. We identified one additional CYP3A4*22 homozygote that received docetaxel in our research cohort, and present this case of severe hematological toxicity. Furthermore, the one other CYP3A4*22 homozygous patient we identified from the literature died from docetaxel toxicity. This case report provides further evidence for the need to better understand the impact of germline CYP3A variants in severe docetaxel toxicity and supports using caution when treating patients with docetaxel who have genetic variants resulting in CYP3A poor metabolizer phenotypes

Clinical Opportunities for Germline Pharmacogenetics and Management of Drug-Drug Interactions in Patients With Advanced Solid Cancers.

PURPOSE: Precision medicine approaches, including germline pharmacogenetics (PGx) and management of drug-drug interactions (DDIs), are likely to benefit patients with advanced cancer who are frequently prescribed multiple concomitant medications to treat cancer and associated conditions. Our objective was to assess the potential opportunities for PGx and DDI management within a cohort of adults with advanced cancer. METHODS: Medication data were collected from the electronic health records for 481 subjects since their first cancer diagnosis. All subjects were genotyped for variants with clinically actionable recommendations in Clinical Pharmacogenetics Implementation Consortium guidelines for 13 pharmacogenes. DDIs were defined as concomitant prescription of strong inhibitors or inducers with sensitive substrates of the same drug-metabolizing enzyme and were assessed for six major cytochrome P450 (CYP) enzymes. RESULTS: Approximately 60% of subjects were prescribed at least one medication with Clinical Pharmacogenetics Implementation Consortium recommendations, and approximately 14% of subjects had an instance for actionable PGx, defined as a prescription for a drug in a subject with an actionable genotype. The overall subject-level prevalence of DDIs and serious DDIs were 50.3% and 34.8%, respectively. Serious DDIs were most common for CYP3A, CYP2D6, and CYP2C19, occurring in 24.9%, 16.8%, and 11.7% of subjects, respectively. When assessing PGx and DDIs together, approximately 40% of subjects had at least one opportunity for a precision medicine-based intervention and approximately 98% of subjects had an actionable phenotype for at least one CYP enzyme. CONCLUSION: Our findings demonstrate numerous clinical opportunities for germline PGx and DDI management in adults with advanced cancer