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Introduction: Oxazolidinones are synthetic antimicrobials with strong bacteriostatic activity against Gram-positive organisms. Recently, tedizolid phosphate was approved for clinical use becoming the second agent of this class after linezolid available in clinical practice., Areas Covered: Oxazolidinone pharmacology including structure-activity relationships, mode of action, pharmacokinetics, drug-drug interactions, and adverse drug reactions is reviewed. Furthermore, bacterial resistance, approved indications, use in paediatric populations, and tuberculosis treatment with oxazolidinones are discussed, and differences in indications and pharmacotoxicological properties between the two approved agents are elucidated. A MEDLINE PubMed search for articles published in English from January 1960 to June 2015 was completed using the terms: oxazolidinone, oxazolidinone-induced toxicity, oxazolidinone pharmacokinetics, serotonin syndrome, oxazolidinone drug-drug interactions, antituberculotic treatment., Expert Opinion: Linezolid illustrates an important antimicrobial in several Gram-positive infections especially when methicillin-resistant Staphylococcus aureus strains are involved. Myelosuppression and neuropathy are toxicities of high relevance particularly in case of prolonged treatment periods. The significance of linezolid in the treatment of extensively drug-resistant tuberculosis has to be further investigated. Tedizolid phosphate represents a welcome addition in our anti-infective arsenal, and future research will clarify its role in indications other than the already approved acute bacterial skin infections.

Unraveling the underlying mechanisms of cetuximab resistance in head and neck squamous cell carcinoma (HNSCC) is of major importance as many tumors remain non-responsive or become resistant. Our microarray results suggest that "resistant" cells still exhibit RAS-MAPK pathway signaling contributing to drug resistance, as witnessed by low expression of DUSP5 and DUSP6, negative regulators of ERK1/2, and increased expression of AURKB, a key regulator of mitosis. Therefore, interrupting the RAS-MAPK pathway by an ERK1/2 inhibitor (apigenin) or an AURKB inhibitor (barasertib) might be a new strategy for overcoming cetuximab resistance in HNSCC., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

People are constantly exposed to environmental chemicals through contact with the atmosphere or by ingestion of food. Therefore, when conducting safety assessments, the immunotoxic effects of combinations of chemicals in addition to toxicities produced by each chemical alone should be considered. The objective of the studies reported here were to demonstrate the combined effects of three well-known environmental immunotoxic chemicals -- methoxychlor (MXC), an organochlorine compound; parathion (PARA), an organophosphate compound; and piperonyl butoxide (PBO), an agricultural insecticide synergist -- by using a short-term oral exposure method. Seven-week-old Balb/cAnN mice received daily oral exposure to either one or two of the environmental immunotoxic chemicals for 5 consecutive days. On Day 2, all mice in each group were immunized with sheep red blood cells (SRBC), and their SRBC-specific IgM responses were analyzed by using an enzyme-linked immunosorbent assay and plaque-forming cell assay. T- and B-cell counts in the mouse spleens were also assessed via surface antigen expression. Mice that received MXC + PARA and PBO + MXC treatment showed marked decreases in SRBC-specific IgM production and T- and B-cell counts compared with those in mice that received vehicle control or the corresponding individual test substance. This suggests that simultaneous exposure to multiple environmental chemicals increases the immunotoxic effects of the chemicals compared to individual exposure.

Objectives: Tedizolid phosphate is a novel antibacterial under investigation for the treatment of gram-positive infections. This study was conducted to assess the pharmacokinetics, safety, and tolerability of intravenous tedizolid phosphate as well as the oral bioavailability of tedizolid phosphate., Design: Double-blind, single-ascending dose, multiple-dose pharmacokinetics study, as well as tolerability and open-label crossover studies., Setting: Single center in the United States (Covance Clinical Research Unit, Madison, WI) between September 2009 and January 2010., Participants: Ninety healthy volunteers., Intervention: Single intravenous (IV) doses of tedizolid phosphate 50 mg (lead-in) and 100-400 mg. Single oral and IV dose of tedizolid phosphate 200 mg in crossover fashion. Multiple IV doses of tedizolid phosphate 200 and 300 mg for up to 7 days., Measurements and Main Results: A dose-dependent increase was observed in the maximum plasma concentration (1.2-5.1 μg/ml) and the area under the concentration-time curve (17.4-58.7 μg × hr/ml) of tedizolid (the microbiologically active moiety of tedizolid phosphate) after single IV doses of tedizolid phosphate 100-400 mg. Administration of IV tedizolid phosphate 200 mg once/day for 7 days resulted in minimal (28%) tedizolid accumulation. The absolute oral bioavailability of tedizolid after a single 200-mg dose of tedizolid phosphate was 91%; pharmacokinetic parameters of tedizolid were similar with oral and IV administration. Treatment-related adverse events occurred in 41% of subjects. Most adverse events were related to infusion site and became more frequent with multiple dosing. In an additional 3-day tolerability study, IV tedizolid phosphate 200 mg and placebo were similarly tolerated, based on visual infusion phlebitis scores., Conclusion: These results from a population of healthy volunteers support once/day dosing of tedizolid phosphate 200 mg with both the oral and IV formulations, without the need for dose adjustment when switching administration routes., (© 2014 Cubist Pharmaceuticals. Pharmacotherapy published by Wiley Periodicals, Inc. on behalf of Pharmacotherapy Publications, Inc.)

Introduction: Sorafenib is the only drug approved by the Food and Drug Administration for metastatic hepatocellular carcinoma (HCC). Triptolide, a diterpene triepoxide, exhibits antineoplastic properties in multiple tumor cell types. In this study, we examined the effects of these agents and their combination on HCC in vitro and in vivo models., Methods: HuH-7 and PLC/PRF/5 cells were treated with triptolide (50 nM), sorafenib (1.25 or 2.5 μM), or a combination of both. Cell viability assay (CCK-8), caspase 3&7 activation, and nuclear factor κB assays were performed. For in vivo studies, 40 mice were implanted with subcutaneous HuH7 tumors and divided into four treatment groups (n = 10); saline control, sorafenib 10 mg/kg PO daily (S), Minnelide (a prodrug of triptolide) 0.21 mg/kg intraperitoneally7 daily (M), and combination of both (C). Tumor volumes were assessed weekly., Results: The combination of triptolide and sorafenib was superior to either drug alone in inducing apoptosis and decreasing viability, whereas triptolide alone was sufficient to decrease nuclear factor κB activity. After 2 weeks of treatment, tumor growth inhibition rates were S = 59%, M = 84%, and C = 93%, whereas tumor volumes in control animals increased by 9-fold. When crossed over to combination treatment, control mice tumor growth volumes plateaued over the following 4 weeks., Conclusion: The combination of sorafenib and triptolide is superior to single drug treatment in increasing cell death and apoptosis in vitro. Combining sorafenib with Minnelide inhibited tumor growth with greater efficacy than single-agent treatments. Importantly, in vivo combination treatment allowed for using a lesser dose of sorafenib (10 mg/kg), which is less than 10% of currently prescribed dose for HCC patients. Therefore, combination treatment could have translational potential in the management of HCC., (Copyright © 2014 Mosby, Inc. All rights reserved.)

The present study aimed to prospectively monitor the vascular disrupting effect of M410 by dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) in rabbits with VX2 liver tumors. Twenty-eight rabbits bearing VX2 tumors in the left lobe of the liver were established and randomly divided into treatment and control groups, intravenously injected with 25 mg/kg M410 or sterile saline, respectively. Conventional and DCE-MRI data were acquired on a 3.0-T MR unit at pretreatment, 4 h, 1, 4, 7 and 14 days post-treatment. Histopathological examinations [hematoxylin and eosin (H&E) and CD34 immunohistochemisty staining] were performed at each time point. The dynamic changes in tumor volume, kinetic DCE-MRI parameter [volume transfer constant (Ktrans)] and histological data were evaluated. Tumors grew slower in the M410 group 4-14 days following treatment, compared with rapidly growing tumors in the control group (P<0.05). At 4 h, 1 and 4 days, Ktrans significantly decreased in the M410 group compared with that in the control group (P<0.05). However, Ktrans values were similar in the two groups for the other time points studied. The changes in DCE-MRI parameters were consistent with the results obtained from H&E and CD34 staining of the tumor tissues. DCE-MRI parameter Ktrans may be used as a non-invasive imaging biomarker to monitor the dynamic histological changes in tumors following treatment with the vascular targeting agent M410.

Background: New antibiotics are needed to treat infections caused by drug-resistant bacteria. Tedizolid is a novel oxazolidinone antibacterial drug designed to provide enhanced activity against Gram-positive pathogens. We aimed to assess the efficacy and safety of intravenous to oral tedizolid for treatment of patients with acute bacterial skin and skin-structure infections., Methods: ESTABLISH-2 was a randomised, double-blind, phase 3, non-inferiority trial done between Sept 28, 2011, and Jan 10, 2013, at 58 centres in nine countries. Patients (aged ≥12 years) with acute bacterial skin and skin-structure infections (cellulitis or erysipelas, major cutaneous abscess, or wound infection) that had a minimum lesion area of 75 cm(2) and were suspected or documented to be associated with a Gram-positive pathogen, were randomly assigned (1:1), via an interactive voice-response system with block randomisation, to receive intravenous once-daily tedizolid (200 mg for 6 days) or twice-daily linezolid (600 mg for 10 days), with optional oral step-down. Randomisation was stratified by geographic region and type of acute bacterial skin and skin-structure infection. The primary endpoint was early clinical response (≥20% reduction in lesion area at 48-72 h compared with baseline), with a non-inferiority margin of -10%. Analysis was by intention to treat. This study is registered with ClinicalTrials.gov, number NCT01421511., Findings: 666 patients were randomly assigned to receive tedizolid (n=332) or linezolid (n=334). 283 (85%) patients in the tedizolid group and 276 (83%) in the linezolid group achieved early clinical response (difference 2·6%, 95% CI -3·0 to 8·2), meeting the prespecified non-inferiority margin. Gastrointestinal adverse events were less frequent with tedizolid than linezolid, taking place in 52 (16%) of 331 patients and 67 (20%) of 327 patients in the safety population. Treatment-emergent adverse events leading to discontinuation of study drug were reported by one (<1%) patient in the tedizolid group and four (1%) patients in the linezolid group., Interpretation: Intravenous to oral once-daily tedizolid 200 mg for 6 days was non-inferior to twice-daily linezolid 600 mg for 10 days for treatment of patients with acute bacterial skin and skin-structure infections. Tedizolid could become a useful option for the treatment of acute bacterial skin and skin-structure infections in the hospital and outpatient settings., Funding: Cubist Pharmaceuticals., (Copyright © 2014 Elsevier Ltd. All rights reserved.)

Psychosis and other mental illnesses are common in HIV-infected patients. Olanzapine is one of the preferred antipsychotic agents for the treatment of schizophrenia. Olanzapine is primarily metabolised by CYP1A2 and uridine diphosphate glucuronosyltransferase (UGT). High-dose ritonavir has been shown to increase olanzapine elimination through induction of CYP1A2 and/or UGT, but the effect of low-dose ritonavir on olanzapine pharmacokinetics is unknown. Fosamprenavir is an HIV protease inhibitor that is boosted by low-dose ritonavir. To compensate for the induction of olanzapine metabolism by fosamprenavir/ritonavir, we hypothesised that a dose increase of olanzapine to 15 mg with fosamprenavir/ritonavir would lead to a similar area under the concentration-time curve (AUC) compared with olanzapine 10 mg alone. An open-label, randomised, two-period, cross-over, single-centre trial was conducted in 24 healthy volunteers. Subjects were randomised to one of the following treatments: (A) fosamprenavir/ritonavir 700/100 mg twice daily (b.i.d.) for 16 days with a single dose of olanzapine 15 mg on Day 13, a wash-out period of 31 days and a single dose of olanzapine 10 mg on Day 48; or (B) the same medication in reverse order. Twenty subjects completed the trial. The geometric mean ratios (90% CI) of olanzapine AUClast, maximum drug concentration (C(max)) and apparent elimination half-life (t(1/2)) when taken with fosamprenavir/ritonavir versus olanzapine alone were 1.00 (0.93-1.08), 1.32 (1.18-1.47) and 0.68 (0.63-0.74), respectively. Fosamprenavir/ritonavir 700/100 mg b.i.d. appeared to induce olanzapine metabolism. We therefore propose a 50% dosage increase of olanzapine when combining with a ritonavir-boosted protease inhibitor., (Copyright © 2014 Elsevier B.V. and the International Society of Chemotherapy. All rights reserved.)

The threshold of toxicological concern (TTC) concept is a risk assessment tool for substances present at low oral exposure and lacking hazard data. In the past, several thresholds were elaborated by Munro et al. (1996) and Kroes et al. (2004). For these TTC thresholds, the Cramer class III threshold is based on a broad spectrum of substances, including organophosphates. For organophosphates a separate threshold was elaborated by Kroes et al. (2004), however without adjustment of the Cramer class III threshold. Moreover, reference was made by Munro et al. (2008) that for organohalogens a separate threshold also may apply whereas the EFSA (2012) considers that carbamate substances with anti-choline esterase activity can be included in the threshold for organophosphates. In this paper, a reevaluation of the Munro dataset (original TTC database) was performed, focused on the thresholds for organophosphates including carbamates, organohalogens and remaining Cramer class III substances. This way thresholds for each of these groups are elaborated. As a results of the current reevaluation of the Munro dataset, thresholds for life-time exposure are elaborated for the group of organophosphates including carbamates, the group of organohalogens and the remaining Cramer class III substances, being 0.30, 1.5 and 4.0 μg/kg bodyweight/day, respectively., (Copyright © 2014 Elsevier Inc. All rights reserved.)

The potent human toxicity of organophosphorus (OP) nerve agents calls for the development of effective antidotes. Standard treatment for nerve agent poisoning with atropine and an oxime has a limited efficacy. An alternative approach is the development of catalytic bioscavengers using OP-hydrolyzing enzymes such as paraoxonases (PON1). Recently, a chimeric PON1 mutant, IIG1, was engineered toward the hydrolysis of the toxic isomers of soman and cyclosarin with high in vitro catalytic efficiency. In order to investigate the suitability of IIG1 as a catalytic bioscavenger, an in vivo guinea pig model was established to determine the protective effect of IIG1 against the highly toxic nerve agent cyclosarin. Prophylactic i.v. injection of IIG1 (1 mg/kg) prevented systemic toxicity in cyclosarin (~2LD50)-poisoned guinea pigs, preserved brain acetylcholinesterase (AChE) activity, and protected erythrocyte AChE activity partially. A lower IIG1 dose (0.2 mg/kg) already prevented mortality and reduced systemic toxicity. IIG1 exhibited a high catalytic efficiency with a homologous series of alkylmethylfluorophosphonates but had low efficiency with the phosphoramidate tabun and was virtually ineffective with the nerve agent VX. This quantitative analysis validated the model for predicting in vivo protection by catalytic bioscavengers based on their catalytic efficiency, the level of circulating enzyme, and the dose of the intoxicating nerve agent. The in vitro and in vivo results indicate that IIG1 may be considered as a promising candidate bioscavenger to protect against the toxic effects of a range of highly toxic nerve agents.

Objectives: To evaluate the clinical performance of two one-step self-etch adhesives in noncarious cervical lesions (NCCL) under active or passive application mode., Methods: Thirty-one patients with four NCCL were enrolled in this study. One hundred and twenty-four restorations were placed according to one of the following conditions: 1) Adper Prompt L-Pop (AP), active application (APA); 2) AP, passive application (APP); 3) Xeno III (XE), active application (XEA), or 4) XE, passive application (XEP). The restorations were evaluated by the FDI World Dental Federation criteria at baseline and after six, 12, and 24 months of clinical service. The effects of adhesive, mode of application, and recall period were assessed via mixed generalized linear model (α=0.05)., Results: The adhesive AP and the passive application mode showed significantly higher marginal staining than did XE and active application, respectively (p<0.05). With regard to the retention rates, the active application mode yielded higher retention rates at the 24-month recall compared to the passive application, regardless of the material. The individual retention rates (95% confidence interval) of both adhesives in the active application mode were the same, 96.8% (83.8-99.4%), while in the passive application rates were 87.1% (71.2-94.9%) and 80.7% (63.7-90.8%) for XE and AP, respectively., Conclusions: The active application improved the retention rates of both adhesives after 24 months and minimized the marginal staining at enamel margins.

Purpose: Pancreatic adenocarcinoma is the fourth leading cause for cancer-related mortality with a survival rate of less than 5%. Late diagnosis and lack of effective chemotherapeutic regimen contribute to these grim survival statistics. Relapse of any tumor is largely attributed to the presence of tumor-initiating cells (TIC) or cancer stem cells (CSC). These cells are considered as hurdles to cancer therapy as no known chemotherapeutic compound is reported to target them. Thus, there is an urgent need to develop a TIC-targeted therapy for pancreatic cancer., Experimental Design: We isolated CD133(+) cells from a spontaneous pancreatic ductal adenocarcinoma mouse model and studied both surface expression, molecular markers of pancreatic TICs. We also studied tumor initiation properties by implanting low numbers of CD133(+) cells in immune competent mice. Effect of Minnelide, a drug currently under phase I clinical trial, was studied on the tumors derived from the CD133(+) cells., Results: Our study showed for the first time that CD133(+) population demonstrated all the molecular markers for pancreatic TIC. These cells initiated tumors in immunocompetent mouse models and showed increased expression of prosurvival and proinvasive proteins compared to the CD133(-) non-TIC population. Our study further showed that Minnelide was very efficient in downregulating both CD133(-) and CD133(+) population in the tumors, resulting in a 60% decrease in tumor volume compared with the untreated ones., Conclusion: As Minnelide is currently under phase I clinical trial, its evaluation in reducing tumor burden by decreasing TIC as well as non-TIC population suggests its potential as an effective therapy., (©2014 AACR.)

Objectives: The single- and multiple-dose pharmacokinetics (PK) of tedizolid were examined after oral administration of tedizolid phosphate disodium (TPD), including the effect of food on PK. The relative bioavailability of TPD to the free acid tedizolid phosphate was determined to bridge the results of these and other studies to the solid form of the prodrug selected for further development., Design: Randomized placebo-controlled, double-blind single- and multiple-ascending dose studies and randomized open-label, crossover food effect and relative bioavailability studies., Setting: Clinical Research Units., Participants: Healthy subjects., Intervention: Study TR701-101 enrolled 40 subjects in single-ascending dose (200-1200 mg TPD or placebo) and 40 subjects in 21-day multiple-ascending dose (200, 300, or 400 mg TPD once/day; 600 mg linezolid twice/day; or placebo) arms. Study TR701-103 was a food-effect study in 12 subjects administered 600 mg TPD. Study TR701-108 was a relative bioavailability study in 12 subjects administered 150-mg tedizolid equivalents as TPD or tedizolid phosphate., Measurements and Main Results: Plasma concentrations of the prodrug tedizolid phosphate, its active moiety tedizolid, and/or linezolid were collected. After administration of 200 to 600 mg TPD, tedizolid values increased approximately dose proportionally in area under the concentration-time curve (AUC) and maximum plasma concentration (Cmax ). Tedizolid half-life values were approximately 2-fold greater compared with linezolid. TPD administration with food delayed tedizolid absorption and reduced Cmax relative to the fasted state but did not alter AUC. Minimal accumulation was predicted and observed for tedizolid, whereas observed accumulation of linezolid exceeded predictions based on single-dose PK. Comparable PK of tedizolid was observed following oral administration of either TPD or tedizolid phosphate. In the multiple-ascending dose study, 3 of 24 tedizolid subjects were withdrawn under prespecified stopping rules (one each of elevated alanine aminotransferase, low reticulocyte count, or low white blood cell count), as was 1 of 8 linezolid subjects (low reticulocyte count)., Conclusions: Overall, tedizolid has a favorable PK profile, a half-life that supports once daily administration, and no nonlinearities at steady state. Tedizolid phosphate can be administered without regard to food., (© 2013 Trius Therapeutics. Pharmacotherapy published by Wiley Periodicals, Inc. on behalf of Pharmacotherapy Publications, Inc.)

Background: The anticancer properties of aspirin are restricted by its gastrointestinal toxicity and its limited efficacy. Therefore, we synthesized phospho-aspirin (PA-2; MDC-22), a novel derivative of aspirin, and evaluated its chemotherapeutic and chemopreventive efficacy in preclinical models of triple negative breast cancer (TNBC)., Methods: Efficacy of PA-2 was evaluated in human breast cancer cells in vitro, and in orthotopic and subcutaneous TNBC xenografts in nude mice. Mechanistic studies were also carried out to elucidate the mechanism of action of PA-2., Results: PA-2 inhibited the growth of TNBC cells in vitro more potently than aspirin. Treatment of established subcutaneous TNBC xenografts (MDA-MB-231 and BT-20) with PA-2 induced a strong growth inhibitory effect, resulting in tumor stasis (79% and 90% inhibition, respectively). PA-2, but not aspirin, significantly prevented the development of orthotopic MDA-MB-231 xenografts (62% inhibition). Mechanistically, PA-2: 1) inhibited the activation of epidermal growth factor receptor (EGFR) and suppressed its downstream signaling cascades, including PI3K/AKT/mTOR and STAT3; 2) induced acetylation of p53 at multiple lysine residues and enhanced its DNA binding activity, leading to cell cycle arrest; and 3) induced oxidative stress by suppressing the thioredoxin system, consequently inhibiting the activation of the redox sensitive transcription factor NF-κB. These molecular alterations were observed in vitro and in vivo, demonstrating their relevance to the anticancer effect of PA-2., Conclusions: Our findings demonstrate that PA-2 possesses potent chemotherapeutic efficacy against TNBC, and is also effective in its chemoprevention, warranting further evaluation as an anticancer agent.

Fosamprenavir (FPV) is the phosphate ester prodrug of the HIV-1 protease inhibitor amprenavir (APV). A pediatric population pharmacokinetic model for APV was developed and simulation was used to identify dosing regimens for pediatric patients receiving FPV in combination with ritonavir (RTV) which resulted in concentrations similar to those in adults receiving FPV/RTV 700/100 mg BID. Pharmacokinetic data was obtained from HIV infected subjects aged 2 months to 18 years receiving either FPV or FPV/RTV. A two-compartment model with first order absorption and elimination was an appropriate structural model. Significant covariates in the model included RTV coadministration on clearance, fed status on bioavailability for the oral suspension, body weight on clearance and volume terms, black race on clearance, and age on clearance. The following FPV/RTV twice daily dosing regimens in pediatric patients delivered plasma APV exposure similar to adults: 45/7 mg/kg in patients weighing <11 kg, 30/3 mg/kg in patients weighing 11 to <15 kg, 23/3 mg/kg in patients weighing 15 to <20 kg, and 18/3 mg/kg in patients weighting ≥20 kg. Additionally children weighing ≥39 kg can receive the adult regimen., (© 2013, The American College of Clinical Pharmacology.)

Background: Pharmacokinetics, safety and antiviral activity of twice-daily fosamprenavir with or without ritonavir were evaluated in 2- to 18-year-old protease inhibitor-naïve and -experienced HIV-1-infected children., Methods: Serial pharmacokinetic samples were collected at week 2 and predose samples every 4-12 weeks. Safety and plasma HIV-1 RNA were monitored every 4-12 weeks., Results: Twenty protease inhibitor-naïve 2- to <6-year-old subjects received antiretroviral treatment including unboosted fosamprenavir twice-daily, whereas 89 protease inhibitor-naïve and -experienced 2- to 18-year-old subjects received fosamprenavir/ritonavir-containing therapy twice-daily. Median fosamprenavir exposure was 891 days (range 15-1805 days), with 88% exposed >48 weeks. Twice-daily doses of fosamprenavir/ritonavir 23/3 mg/kg in 2- to <6-year olds, 18/3 mg/kg in ≥6-year olds and 700/100 mg in adolescents achieved plasma amprenavir exposures comparable with or higher than 700/100 mg twice-daily in adults while fosamprenavir 30 mg/kg twice-daily in 2- to <6-year olds led to exposures higher than 1400 mg twice-daily in adults. The proportion of subjects with HIV-1 RNA <400 copies/mL at week 48 was 60% for fosamprenavir and 53-74% for fosamprenavir/ritonavir (intent-to-treat [exposed], snapshot analysis). Median increases in absolute and relative (percentage) CD4 counts from baseline to week 48 occurred in both the fosamprenavir (340 cells/mm; 8%) and fosamprenavir/ritonavir group (190 cells/mm; 8%). The most common adverse events were vomiting, cough, and diarrhea; 18 subjects experienced serious adverse events, including 9 with suspected abacavir hypersensitivity., Conclusions: Fosamprenavir regimens administered to HIV-1-infected children aged 2-18 years were generally well-tolerated and provided sustained antiviral activity over 48 weeks, with plasma amprenavir exposures comparable with or higher than adults.

In the Staphylococcus aureus neutropenic murine thigh-infection model, the ratio of the free area under the 24-hour concentration-time curve to the minimum inhibitory concentration (fAUC/MIC) was found to be the pharmacodynamic index most closely linked to bacterial effect, with a ratio of approximately 50 producing a static effect. Further work was undertaken in neutropenic versus non-neutropenic animals. The presence of granulocytes increased the activity of tedizolid considerably, 25-fold on average, and maximal effect was achieved at an exposure equivalent to approximately 200 mg tedizolid phosphate per day in humans (dosing regimen used in phase 2 and 3 clinical trials). The fAUC/MIC was also found to be the pharmacodynamically linked variable in the S. aureus neutropenic murine pneumonia model; the fAUC/MIC ratio required for a static effect was approximately 20. Pharmacokinetic (PK) data demonstrate that tedizolid penetrates well into the epithelial lining fluid (ELF) of the lung. Data from the pneumonia infection model and ELF penetration PK study support exploring its use in pneumonia.

Background: Pharmacokinetics, safety and antiviral activity of fosamprenavir (FPV) with ritonavir (RTV) twice daily were evaluated in HIV-1-infected infants and children 4 weeks to <2 years over 48 weeks., Methods: Results from intensive pharmacokinetic sampling of subjects enrolled in single dose visits was used to determine individualized dosing for the first 6-10 subjects in each of 2 cohorts (4 weeks to <6 months, 6 months to <2 years); steady state pharmacokinetic data were then used to select the dosage regimen for the remaining subjects recruited to the cohort. Intensive pharmacokinetic sampling was performed at week 2 or 8; predose samples were collected every 4-12 weeks thereafter. Safety and plasma HIV-1 RNA were monitored every 4-12 weeks., Results: Fifty-nine subjects received study medication. FPV 45 mg/kg boosted with RTV 7 to 10 mg/kg BID achieved average plasma amprenavir area under curve(0-τ) values 26% to 28% lower and Cmax similar to historical adult data for FPV/RTV 700/100 mg BID; amprenavir Cτ values were lower in the subjects <6 months of age. At week 48, 35 of 54 (65%) subjects had achieved plasma HIV-1 RNA <400 copies/mL and 33 of 54 (61%) had plasma HIV-1 RNA values <50 copies/mL. The most common adverse events were diarrhea, upper respiratory tract infection, gastroenteritis and otitis media., Conclusions: Final FPV/RTV dosing regimens achieved plasma amprenavir exposures comparable with those from regimens approved in adults, with the exception of trough exposures in the <6-month-old infants. The FPV/RTV regimens led to viral suppression in 61% of patients and were generally well tolerated.

Introduction: Barasertib is the pro-drug of barasertib-hydroxy-quinazoline pyrazole anilide, a selective Aurora B kinase inhibitor that has demonstrated preliminary anti-AML activity in the clinical setting., Patients and Methods: This Phase I dose-escalation study evaluated the safety and tolerability of barasertib, combined with LDAC, in patients aged 60 years or older with de novo or secondary AML. Barasertib (7-day continuous intravenous infusion) plus LDAC 20 mg (subcutaneous injection twice daily for 10 days) was administered in 28-day cycles. The MTD was defined as the highest dose at which ≤ 1 patient within a cohort of 6 experienced a dose-limiting toxicity (DLT) (clinically significant adverse event [AE] or laboratory abnormality considered related to barasertib). The MTD cohort was expanded to 12 patients., Results: Twenty-two patients (median age, 71 years) received ≥ 1 treatment cycle (n = 6, 800 mg; n = 13, 1000 mg; n = 3, 1200 mg). DLTs were reported in 2 patients (both, National Cancer Institute Common Terminology Criteria for Adverse Events grade 3 stomatitis/mucositis; 1200 mg cohort). The most common AEs were infection (73%), febrile neutropenia (59%), nausea (50%), and diarrhea (46%). Barasertib plus LDAC resulted in an overall response rate (International Working Group criteria) of 45% (n = 10/22; according to investigator opinion)., Conclusion: The MTD of 1000 mg barasertib in combination with LDAC in older patients with AML was associated with acceptable tolerability and preliminary anti-AML activity., (Copyright © 2013 Elsevier Inc. All rights reserved.)

BNC105P is a tubulin polymerisation inhibitor that selectively disrupts tumour vasculature and suppresses cancer cell proliferation. This agent has exhibited preclinical and phase I activity in Malignant Pleural Mesothelioma (MPM). This phase II, single arm trial investigated the efficacy and safety of BNC105P as second line therapy in MPM. Participants had progressive MPM after first line pemetrexed/platinum chemotherapy, ECOG PS 0-1, adequate organ function, and measurable disease. BNC105P 16 mg/m(2) was administered intravenously on day 1 and 8 every 21 days until progression or undue toxicity. The primary endpoint was centrally reviewed objective response rate (RR). Tumour response was assessed every two cycles using modified RECIST. 30 patients were enrolled in 10 months, predominantly male (90%), ECOG PS 1 (77%), epithelioid histology (67%), and non-metastatic disease (67%). All patients received at least one dose of study drug, with a median of 2 cycles. No significant haematologic, biochemical, or cardiac adverse events (AEs) were observed. Grade 3 or 4 AEs occurred in 10 patients (33%). There were 2 deaths on study: 1 cardiorespiratory, the other to pneumonia. We observed 1 partial response (3%); 13 patients had stable disease (43%). Median progression free survival was 1.5 months (95% CI 1.4-2.4); median overall survival was 8.2 months (95% CI 3.8-11.9). BNC105P was safe and tolerable. The sole response was insufficient to warrant further research as a single agent., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Purpose: Heat shot protein 90 (Hsp90) is a ubiquitous molecular chaperone involved in protein folding, activation, and assembly, including key mediators of signal transduction, cell-cycle control, and transcriptional regulation. We conducted a phase I dose-finding and pharmacokinetic/pharmacodynamic study of BIIB028, a prodrug designed to inhibit Hsp90 activity., Experimental Design: Patients with advanced solid tumors were enrolled and received escalating doses of BIIB028 intravenously twice a week in 21-day cycles (3+3 design). Response was evaluated after two cycles., Results: Forty-one patients received doses of 6 to 192 mg/m2. The maximum tolerated dose was 144 mg/m2. Dose-limiting toxicities were syncope (n=1) and fatigue (n=1). Common toxicities at least possibly related to drug were grades 1 to 2, including fatigue (46%), diarrhea (44%), nausea (44%), vomiting (29%), hot flushes (29%), and abnormal dreams (17%). The concentration-time curves for day 1 and day 18 for both prodrug and active metabolite (CF2772) showed a negligible difference. There was a dose-dependent increase in plasma exposure for BIIB028 (CF3647) and CF2772 with plasma half-life of 0.5 and 2.1 hours, respectively. Pharmacodynamic analyses showed significant increases in Hsp70 in peripheral blood mononuclear cells and significantly decreased circulating human EGF receptor-2 extracellular domain in all patients who received BIIB028 at dose levels of 48 mg/m2 or more. Stable disease for at least eight cycles (24 weeks) was achieved in 5 (12%) patients (for durations of 6, 6, 8, 12.5, and 19 months)., Conclusion: BIIB028 is a well-tolerated molecule that showed target impact and was associated with prolonged stable disease in two patients., (©2013 AACR.)

Background: In this phase 2 study, the authors evaluated the efficacy, safety, and tolerability of the Aurora B kinase inhibitor barasertib compared with low-dose cytosine arabinoside (LDAC) in patients aged ≥ 60 years with acute myeloid leukemia (AML)., Methods: Patients were randomized 2:1 to receive either open-label barasertib 1200 mg (as a 7-day intravenous infusion) or LDAC 20 mg (subcutaneously twice daily for 10 days) in 28-day cycles. The primary endpoint was the objective complete response rate (OCRR) (complete responses [CR] plus confirmed CRs with incomplete recovery of neutrophils or platelets [CRi] according to Cheson criteria [also requiring reconfirmation of CRi ≥21 days after the first appearance and associated with partial recovery of platelets and neutrophils]). Secondary endpoints included overall survival (OS) and safety., Results: In total, 74 patients (barasertib, n = 48; LDAC, n = 26) completed ≥1 cycle of treatment. A significant improvement in the OCRR was observed with barasertib (35.4% vs 11.5%; difference, 23.9%; 95% confidence interval, 2.7%-39.9%; P < .05). Although the study was not formally sized to compare OS data, the median OS with barasertib was 8.2 months versus 4.5 months with LDAC (hazard ratio, 0.88; 95% confidence interval, 0.49-1.58; P = .663). Stomatitis and febrile neutropenia were the most common adverse events with barasertib versus LDAC (71% vs 15% and 67% vs 19%, respectively)., Conclusions: Barasertib produced a significant improvement in the OCRR versus LDAC and had a more toxic but manageable safety profile, consistent with previous studies., (© 2013 American Cancer Society.)

Barasertib, an aurora B inhibitor, terminates cell division, introduces polyploidy, and consequently causes apoptosis. In the present study, we evaluated the effect of the combination of barasertib and cytarabine (ara-C), a key agent for leukemia chemotherapy, on leukemic cells in vitro. Human leukemia HL-60 cells and HL-60/ara-C20 cells, a 20-fold ara-C-resistant variant, were used. The 50% growth inhibitory concentrations of an active metabolite of barasertib, barasertib-hydroxyquinazoline-pyrazol-aniline (Barasertib-HQPA), and ara-C were 51 nM and 300 nM for HL-60 cells and 70 nM and 5300 nM for HL-60/ara-C20 cells, respectively. Barasertib-HQPA induced polyploidy with a subsequent induction of sub-G1 phase apoptosis, indicating the M-phase specific cytotoxicity. Cells treated with the S-phase specific ara-C accumulated in S phase and subsequently died through apoptosis. When HL-60 cells were treated with barasertib-HQPA and ara-C in combination, a greater-than-additive apoptosis was induced. This enhancement was obtained when the cells were treated with barasertib-HQPA prior to ara-C (37.9% sub-G1) or with both concurrently (31.2% sub-G1), but not with ara-C prior to barasertib-HQPA (17.8% sub-G1). The combination effects were similarly obtained in HL-60/ara-C20 cells with 19.7% sub-G1 for barasertib-HQPA→ara-C, 18.4% sub-G1 for both concurrently, and 13.8% sub-G1 for ara-C→barasertib-HQPA, and another leukemic U937 cells with 25.4% sub-G1 for barasertib-HQPA→ara-C, 28.2% sub-G1 for both concurrently, and 16.0% sub-G1 for ara-C→barasertib-HQPA. Barasertib-HQPA inhibited aurora B autophosphorylation and histone H3 phosphorylation in all the cell lines. Barasertib-HQPA did not inhibit DNA synthesis, allowing ara-C incorporation into DNA for its cytotoxicity. Thus, barasertib-HQPA and ara-C provided a greater-than-additive cytotoxicity in leukemic cells in vitro., (© 2013 Japanese Cancer Association.)

BMS-663068 is a phosphonooxymethyl ester prodrug under development for the treatment of HIV/AIDS. The prodrug is designed to overcome the solubility-limited bioavailability of the active moiety, BMS-626529. BMS-663068 is not absorbed from the gastrointestinal (GI) tract and requires enzymatic conversion by alkaline phosphatase to BMS-626529 immediately before absorption. In the light of the known short in vivo half-life of BMS-626529, compartmental absorption modeling was used to predict the potential feasibility of extended-release (ER) delivery to achieve target Cmax :Cmin ratios. To further refine the model with respect to colonic absorption, the regional absorption of BMS-626529 following delivery of BMS-663068 to upper and lower GI sites was characterized through a site of absorption study in human subjects. A refined model was subsequently applied to guide the development of ER tablet formulations. Comparisons of results from the refined model to the in vivo human pharmacokinetic data for three selected ER formulations demonstrate the utility of the model in predicting feasibility of ER delivery and in directing formulation development., (Copyright © 2013 Wiley Periodicals, Inc.)

The concept of gene therapy is promising; however, the perceived risks and side effects associated with this technology have severely dampened the researchers' enthusiasm. Thus, the development of a nonviral gene vector without immunological effects and with high transfection efficiency is necessary. Currently, most nonviral vectors have failed to achieve the in vivo transfection efficiencies of viral vectors due to their toxicity, rapid clearance, and/or inappropriate release rates. Although our previous studies have successfully demonstrated the controlled-release of plasmid DNA (pDNA) polyplexes encapsulated into nanoparticles formulated with l-tyrosine polyphosphate (LTP-pDNA nanoparticles), the in vivo transfection capabilities and immunogenicity of this delivery system have yet to be examined. Thus, we evaluate LTP-pDNA nanoparticles in an in vivo setting via injection into rodent uterine tissue. Our results demonstrate through X-gal staining and immunohistochemistry of uterine tissue that transfection has successfully occurred after a nine-day incubation. In contrast, the results for the control nanoparticles show results similar to those of shams. Furthermore, reverse transcriptase polymerase chain reaction (RT-PCR) from the injected tissues confirms the transfection in vivo. To examine the immunogenicity, the l-tyrosine polyphosphate (LTP) nanoparticles have been evaluated in a mouse model. No significant differences in the activation of the innate immune system are observed. These data provide the first report for the potential use of controlled-release nanoparticles formulated from an amino acid based polymer as an in vivo nonviral vector for gene therapy.

Metabolic abnormalities associated with cumulative exposure to antiretroviral therapy have been linked to an increased risk of myocardial infarction in HIV positive individuals. The aim of this study was to evaluate whether the switch from lopinavir/ritonavir (LPV/r) or fosamprenavir/ritonavir (FPV/r) to darunavir/ritonavir (DRV/r) is able to improve the lipid profile. A total of 13 Caucasian subjects (7 from LPV/r and 6 from FPV/r) were enrolled in the study and received DRV/r at the dose of 800/100 mg, without change in their NRTI backbone. Viro-immunological parameters, triglycerides (TGs), total cholesterol (TCh), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) cholesterol, fasting glucose, HOMA-IR, indexes of hepatic and renal functionality, microalbuminuria and cystatin C were measured at baseline (T0), 3 months (T3), 6 months (T6), and 12 months (T12). The switch to DRV/r reduced levels of TCh, LDL, and TGs at T3. Similar improvements were confirmed further at T6 and at T12. A 14% increase in CD4+ count cells (P < 0.05) was observed. Serum cystatin C values showed a statistically significant decrease. After 12 months of switching to DRV/r from LPV/r or FPV/r, patients infected with HIV with TGs above 200 mg/dl, showed a 49% decrease in TGs, along with a 16% reduction of LDL and 19% reduction of TCh. Switching to DRV/r also improved immunological parameters, such as CD4+ cells count and cystatin C plasmatic levels, which may translate into a reduction of the cardiovascular risk. In conclusion, a switch to DRV/r should be considered in those HIV positive patients undergoing antiretroviral therapy, who also present abnormal lipid profiles., (Copyright © 2013 Wiley Periodicals, Inc.)

Steady-state pharmacokinetics in pregnant women prescribed ritonavir-boosted fosamprenavir (FPV) to prevent HIV transmission were assessed in the second trimester, third trimester, and postpartum. Compared with postpartum, geometric mean amprenavir (APV, FPVs active metabolite) area under the plasma concentration-time curves were 35% lower in the second trimester and 25% lower in the third trimester. Maternal APV concentrations were 9- to 15-fold above the mean APV protein-adjusted 50% inhibitory concentration for wild-type HIV. Median ratio of cord blood/maternal APV levels was 0.27, and all infants were HIV negative. FPV/ritonavir during pregnancy was well tolerated and led to virologic suppression.

Background: High phosphate levels attenuate nephroprotection through angiotensin-converting enzyme inhibition in patients with proteinuric chronic kidney disease (CKD). Whether this phenomenon holds true for other nephroprotective interventions like very-low-protein diet (VLPD) is unknown., Methods: We tested the hypothesis that phosphate interferes with the anti-proteinuric response to VLPD in a non-randomized, sequential study in 99 proteinuric CKD patients who sequentially underwent low-protein diet (LPD; 0.6 g/kg) and VLPD (0.3 g/kg) supplemented with keto-analogues, each for periods longer than 1 year., Results: Serum phosphate significantly reduced during VLPD (3.2 ± 0.6 mg/dL) when compared with LPD (3.7 ± 0.6 mg/dL, P < 0.001), an effect paralleled by a substantial decline in phosphate excretion (LPD, 649 ± 180 mg/day; VLPD, 462 ± 97 mg/day; P < 0.001). The median proteinuria during LPD was 1910 mg/24 h (interquartile range: 1445-2376 mg/24 h) and reduced to 987 mg/24 h (656-1300 mg/24 h) during VLPD (P < 0.001). No significant change in the estimated glomerular filtration rate (eGFR) was observed during the two diet periods. In linear mixed models including the diagnosis of renal disease, eGFR, 24-h urine sodium and urea and other potential confounders, there was a strong interaction between serum phosphate (P = 0.04) and phosphaturia (P < 0.001) with the anti-proteinuric response to VLPD. Accordingly, 24-h proteinuria reduced modestly in patients who maintained relatively higher serum phosphate levels or relatively higher phosphaturia to be maximal in those who achieved the lowest level of serum and urine phosphate., Conclusion: Phosphate is an important modifier of the anti-proteinuric response to VLPD. Reducing phosphate burden may decrease proteinuria and slow the progression of renal disease in CKD patients, an issue that remains to be tested in specific clinical trials.

Objectives: The aim of the study was to assess whether pill burden is associated with self-reported adherence to current combination antiretroviral regimens and health status in a large sample of unselected and chronically treated HIV-infected patients., Methods: An adherence and health status questionnaire was offered to all patients collecting their drugs between March and May 2010 at our clinic; both parameters were primarily evaluated using a visual analogue scale. Linear correlations were evaluated using Spearman's correlation coefficient. Wilcoxon's rank-sum test and the χ(2) test were used to compare quantitative and qualitative variables. The generalized linear model was used in multivariable analyses., Results: Among 2763 subjects on treatment during the study period, 2114 (78.8% male; mean age 46.9 ± 8.84 years) were tested for adherence; 1803 (85.3%) had viral loads < 50 HIV-1 RNA copies/mL. After adjusting for age, gender, HIV risk factor, current CD4 count, pill burden and dosing interval, adherence was higher in patients with undetectable HIV RNA (P < 0.0001) and directly associated with current CD4 count (P = 0.029). After adjusting for the same variables, health status was better in patients with undetectable viraemia (P = 0.004) and in men who have sex with men (MSM) and heterosexuals compared with injecting drug users and those with other risk factors (P < 0.0001 for MSM and P = 0.008 for heterosexuals); it was also directly associated with current CD4 count (P < 0.0001) and inversely associated with age (P < 0.0001) and pill burden (P = 0.019)., Conclusions: In this highly adherent population, the number of daily pills was related to self-reported health status but not to self-reported adherence, whereas the dosing interval did not influence self-reported adherence or health status., (© 2012 British HIV Association.)

The cancer chemopreventive properties and gastrointestinal toxicity of ibuprofen are well documented. Modification of existing NSAIDs has improved on the chemopreventive efficacy of this agent and reduced its toxicity. In this study, ibuprofen and a modified derivative (phospho-modified ibuprofen or p-ibuprofen) were used in a chemically induced model of colon cancer. Fisher 344 rats were injected with azoxymethane then treated with either ibuprofen (500 ppm) or p-ibuprofen (900 ppm) for 20 weeks to observe aberrant crypt foci (ACF) or 40 weeks to evaluate tumor incidence and multiplicity. β-catenin and p65 were measured in colonic tissues by immunofluorescence staining. Equal molar doses of ibuprofen (75 and 670 mg/kg) and p-ibuprofen (135 and 1,215 mg/kg) were administered to rats for 7 days to assess acute toxicity. The in vitro effect of p-ibuprofen on COX-2 and PGE(2) synthesis, β-catenin expression and NF-κB activity were examined in RAW 264.7 macrophage and HCT 116 colon cancer cells. At week 20, p-ibuprofen and ibuprofen significantly reduced the multiplicity of ACF compared with control (p<0.05); 31.2 and 37.9%, respectively. At week 40, p-ibuprofen and ibuprofen reduced the multiplicity of colon tumors compared with control (p<0.01) by 47.2 and 56.6%, respectively. Equal molar concentrations of ibuprofen (670 mg/kg) and p-ibuprofen (1,215 mg/kg) resulted in stomach ulceration in 85.7% (6 out of 7) and 14.3% (1 out of 7) of rats, respectively, with p<0.01. Immunofluoresence staining and western blot analysis demonstrated that both ibuprofen and p-ibuprofen suppressed β-catenin nuclear translocation in colon cancer cells. In addition, p-ibuprofen but not ibuprofen inhibited NF-κB activation in colon cancer cells. Collectively, these results suggest that p-ibuprofen is a potential effective novel drug for long-term use in colon cancer prevention.

We herein report the case of an 85-year-old woman presenting with right internal jugular vein candidal thrombophlebitis associated with central venous catheters (CTCVC). The infecting agent was Candida albicans, which caused recurrent candidemia five times in total. Micafungin (MCFG) alone was ineffective; however, the combination of MCFG with fosfluconazole (F-FLCZ) successfully treated the patient without a need for any anticoagulant or surgical therapies. To the extent of our knowledge, this is the first report of CTCVC being successfully treated with a combination of F-FLCZ and MCFG. These new antifungal agents have better efficacy, tolerability and bioavailability; therefore, they can be useful alternatives to classical combination therapies such as amphotericin-B and 5-fluorocytosine.

Objective: To investigate whether AZD1152 (AZD), the selective inhibitor of aurora kinase B, may play a role in the treatment of cisplatin-resistant ovarian carcinoma when administrated alone or in combination with cisplatin., Methods: Hey (cisplatin-resistant ovarian cancer cell line) cells were analyzed. According to the treatment plan, Hey cells were divided into four groups (AZD group, cisplatin group, AZD + cisplatin group and control group). Methyl thiazolyl tetrazolium (MTT) assay was used to test the cells proliferation, caspase-3/7 activity analysis was used to analyze cells apoptosis, and fluorescence in-situ hybridization (FISH) assay was used to determine the copy the number of chromosome 7 and checked the copy numbers of hTERC gene and C-myc gene., Results: MTT test showed that proliferation of AZD group was lower than that in control group (P < 0.01). The cells proliferation with the treatment with 10 and 20 nmol/L AZD for 24 hours was (81.4 ± 3.6)% and (81.4 ± 3.6)% respectively, and the cells proliferation for 48 hours was (43.1 ± 2.0)% and (38.5 ± 1.6)% respectively, which was significantly lower than control group (100%, P < 0.01); Treated with the same concentration of AZD, inhibition of proliferation was significantly enhanced as the time extended (P < 0.01). Proliferation in group AZD + cisplatin was lower than that in cisplatin group (P < 0.01) which suggest that there were additive effects after combined AZD with cisplatin. Compared with control group, caspase-3/7 activity in AZD group increased significantly (P = 0.000), and the same results was seen between AZD + cisplatin group and cisplatin group or AZD group (all P < 0.01). Compared with cisplatin group or control group, the copy numbers of hTERC, C-myc and the number of chromosome were significantly increased in AZD group and AZD + cisplat group (all P < 0.05)., Conclusions: AZD could inhibit ovarian cancer cells proliferation and induce cells apoptosis significantly. AZD alone or in combination with cisplatin may result in the increased cells polyploidy.

We develop a mathematical model of nanoparticles depositing onto and penetrating into a biofilm grown in a parallel-plate flow cell. We carry out deposition experiments in a flow cell to support the modeling. The modeling and the experiments are motivated by the potential use of polymer nanoparticles as part of a treatment strategy for killing biofilms infecting the deep passages in the lungs. In the experiments and model, a fluid carrying polymer nanoparticles is injected into a parallel-plate flow cell in which a biofilm has grown over the bottom plate. The model consists of a system of transport equations describing the deposition and diffusion of nanoparticles. Standard asymptotic techniques that exploit the aspect ratio of the flow cell are applied to reduce the model to two coupled partial differential equations. We perform numerical simulations using the reduced model. We compare the experimental observations with the simulation results to estimate the nanoparticle sticking coefficient and the diffusion coefficient of the nanoparticles in the biofilm. The distributions of nanoparticles through the thickness of the biofilm are consistent with diffusive transport, and uniform distributions through the thickness are achieved in about four hours. Nanoparticle deposition does not appear to be strongly influenced by the flow rate in the cell for the low flow rates considered.

In this study we endeavored to determine the seroprevalence of tick-borne infections in the military working dog (MWD) population in the Republic of Korea (ROK). Our sample population consisted of 182 serum samples from MWDs for 3 different years (1996, 2002, and 2007). In addition, 63 whole blood samples from 2007 were available for polymerase chain reaction (PCR). Serum samples were evaluated by a commercially available enzyme-linked immunosorbent assay (ELISA) and immunofluorescence assay (IFA) for Ehrlichia canis and Anaplasma phagocytophilum, and by ELISA only for Borrelia burgdorferi. PCR amplification of DNA was performed to screen for Ehrlichia canis, E. chaffeensis, E. ewingii, Anaplasma phagocytophilum, A. platys, Borrelia burgdorferi, and Rickettsia rickettsii, as well as Babesia and Theileria species using previously published primers and probes. A total of 56 (30.8%) MWDs were positive by at least one serologic test. Seroprevalences for Anaplasma and Ehrlichia were 4.4% and 0.6% based on the ELISA, and 24.7% and 22.5% based on the IFA, respectively. ELISA testing for Borrelia yielded 2 (1.1%) positive results. In parallel testing using both the ELISA and IFA tests, the percentages of dogs with one or more positive results were 34.1%, 25.9%, and 28.4%, for 1996, 2002, and 2007, respectively. There was no significant differences in seroprevalence based on location, year, breed, or sex of the MWD. There was poor agreement between IFA and ELISA test results. No MWD sample had a positive PCR result. MWDs stationed in Korea had serologic evidence of exposure to several tick-borne pathogens, but PCR testing did not identify any active infections.

Prophylactic administration of reversible acetylcholinesterase (AChE) inhibitors can protect against the lethal effects of organophosphorus compounds (OPCs). The usefulness of pyridostigmine, the only compound approved by the Food and Drug Administration (FDA) for such pretreatment, has been questioned. In search for more efficacious alternatives, we have examined in vivo the efficacy of a group of ten compounds with known anti-AChE activity (pyridostigmine, metoclopramide, tiapride, ranitidine, physostigmine, tacrine, amiloride, methylene blue, 7- methoxytacrine and K-27) to reduce mortality induced by the OPC methyl-paraoxon. AChE inhibitors were given intraperitoneally in equitoxic dosage (25% of LD₀₁) 30 min before OPC exposure. Protection was quantified in rats by determining the relative risk of death (RR) by Cox analysis, with RR=1 for animals given only methyl-paraoxon, but no pretreatment. Only physostigmine (RR=0.39), K-27 (RR=0.40) and tacrine (RR=0.48) significantly (p≤ 0.05) reduced methylparaoxon- induced mortality, when given prophylactically. Pretreatment with pyridostigmine, ranitidine, tiapride, amiloride, metoclopramide and methylene blue did not significantly protect against the lethal effects of methyl-paraoxon. 7-methoxytacrine (7-MEOTA) significantly (p≤ 0.05) increased the relative risk of methyl-paraoxon-induced death (RR=1.31). These results indicate that pretreatment with pyridostigmine cannot be considered a broad-spectrum approach against OPC exposure. K-27 may be a suitable alternative if passage into the brain is contraindicated.

Background: Erufosine is a promising anticancer drug that increases the efficacy of radiotherapy in glioblastoma cell lines in vitro. Moreover, treatment of nude mice with repeated intraperitoneal or subcutaneous injections of Erufosine is well tolerated and yields drug concentrations in the brain tissue that are higher than the concentrations required for cytotoxic drug effects on glioblastoma cell lines in vitro., Methods: In the present study we aimed to evaluate the effects of a combined treatment with radiotherapy and Erufosine on growth and local control of T98G subcutaneous glioblastoma xenograft-tumours in NMRI nu/nu mice., Results: We show that repeated intraperitoneal injections of Erufosine resulted in a significant drug accumulation in T98G xenograft tumours on NMRI nu/nu mice. Moreover, short-term treatment with 5 intraperitoneal Erufosine injections caused a transient decrease in the growth of T98G tumours without radiotherapy. Furthermore, an increased radiation-induced growth delay of T98G xenograft tumours was observed when fractionated irradiation was combined with short-term Erufosine-treatment. However, no beneficial drug effects on fractionated radiotherapy in terms of local tumour control were observed., Conclusions: We conclude that short-term treatment with Erufosine is not sufficient to significantly improve local control in combination with radiotherapy in T98G glioblastoma xenograft tumours. Further studies are needed to evaluate efficacy of extended drug treatment schedules.

We report a rare case of cryptococcal meningoencephalitis in which antifungal therapy was monitored by measuring the cerebrospinal fluid (CSF) levels of the antifungal drugs. A 78-year-old man with diabetes mellitus being treated with oral agents. He had no history of human immunodeficiency virus infection. The patient showed abnormal behavior and fever (>38°C) on November 20, 2009, and was admitted for disturbance of consciousness on November 24. CSF examination showed an increased cell count, and a yeast-like fungus, suggesting cryptococcal meningoencephalitis, was observed by India ink staining. Initial treatment was liposomal amphotericin B (L-AMB) plus flucytosine. Cryptococcus neoformans was isolated by CSF culture on day 2. MIC was 0.25 μg/ml for amphotericin B (AMPH-B), 4 μg/ml for flucytosine, 4 μg/ml for fluconazole (FLCZ), and 0.03 μg/ml for voriconazole (VRCZ). Despite treatment, his disturbance of consciousness persisted. The CSF level of AMPH-B was ≤0.05 μg/ml on day 8. Therefore, L-AMB was switched to fosfluconazole. The CSF level of FLCZ was sufficient (22.6 μg/ml) on day 25, but there was a decrease in glucose and the fungus could still be detected in CSF smears. Consequently, FLCZ was switched to VRCZ. On day 47, CSF level of VRCZ was 1.97 μg/ml, exceeding its MIC, so treatment was continued. On day 77, the patient was generally lucid, and CSF smears did not detect any fungi. The patient was then transferred for rehabilitation. On day 84, voriconazole was discontinued, with no evidence of fungal recurrence.

Background: Although dual-boosted protease inhibitors regimen is not recommended in children with HIV infection, such a strategy could be useful in subjects with a complex resistance profile. This study was aimed at assessing the long term efficacy and safety of a double-boosted protease inhibitor combination, fosamprenavir (fAVP) and atazanavir/ritonavir (ATV/r) in a cohort of HIV-infected children and adolescents who had failed with nucleoside reverse transcriptase inhibitors., Methods: Seven vertically infected children and adolescents who had previously failed highly active antiretroviral therapy and were resistant to nucleoside reverse transcriptase inhibitors, received a dual protease inhibitor (PI) regimen including fAVP plus ATV/r for 42 months. The patients were assessed at baseline, every month for the first 24 weeks of therapy and every 3 months until month 32. Physical examination, CD4+ cell count, HIV-RNA viral load, lipid profile and hepatic function were assessed throughout the follow up., Results: During the study no serious adverse events were reported. CD4 absolute number increased over-time in all subjects. At baseline the median HIV-RNA was 6562 cp/mL (ranging 1048 -102772 cp/mL) and rapidly decreased below the limit of detection (50 cp/mL) after 2 months of the new treatment and remained undetectable in all cases through the entire study period. At the beginning of the study all cases showed a normal lipid profile. During the study period, 4/7 subjects showed total cholesterol, low density lipoprotein and triglyceride levels >97th cent.le for the males and 94th cent.le for the females. HDL cholesterol showed protective values. Hepatic enzymes remained stable during the entire observation, whereas total bilirubin showed toxicity II/III grade in 6/7 subjects. No change in fat redistribution and insulin resistance was observed., Conclusion: Dual-boosted protease inhibitor therapy was virologically and immunologically effective and it could be considered as a possible alternative to a rescue regimen in children and adolescents. However, hypercholesterolemia and hypertriglyceridemia need close follow-up and may limit the use of this therapeutic option.

Although Listeria monocytogenes can induce systemic infection causing spontaneous abortion, septicemia, and meningitis, studies have not been performed to investigate human anti-L. monocytogenes immune responses, including those of Ag-specific Vγ2Vδ2 T cells, a dominant human γδ T cell subset. L. monocytogenes is the only pathogen known to possess both the mevalonate and non-mevalonate isoprenoid biosynthesis pathways that produce metabolic phosphates or phosphoantigens activating human Vγ2Vδ2 T cells, making it interesting to explore in vivo anti-L. monocytogenes immune responses of Vγ2Vδ2 T cells. In this study, we demonstrated that subclinical systemic L. monocytogenes infection of rhesus macaques via parenteral inoculation or vaccination with an attenuated Listeria strain induced multieffector-functional immune responses of phosphoantigen-specific Vγ2Vδ2 T cells. Subclinical systemic infection and reinfection with attenuated L. monocytogenes uncovered the ability of Vγ2Vδ2 T cells to mount expansion and adaptive or recall-like expansion. Expanded Vγ2Vδ2 T cells could traffic to and accumulate in the pulmonary compartment and intestinal mucosa. Expanded Vγ2Vδ2 T cells could evolve into effector cells producing IFN-γ, TNF-α, IL-4, IL-17, or perforin after L. monocytogenes infection, and some effector Vγ2Vδ2 T cells could coproduce IL-17 and IFN-γ, IL-4 and IFN-γ, or TNF-α and perforin. Surprisingly, in vivo-expanded Vγ2Vδ2 T effector cells in subclinical L. monocytogenes infection could directly lyse L. monocytogenes-infected target cells and inhibit intracellular L. monocytogenes bacteria. Thus, we present the first demonstration, to our knowledge, of multieffector-functional Vγ2Vδ2 T cell responses against L. monocytogenes.

Introduction: Modeling and simulation of pharmacokinetics and pharmacodynamics has previously been shown to be potentially useful in designing Phase I programs of novel anti-cancer agents that show hematological toxicity. In this analysis, a two-stage model-based trial design was evaluated retrospectively using data from the Phase I program with the aurora kinase inhibitor barasertib., Methods: Data from two Phase I trials and four regimens were used (n = 79). Using barasertib-hydroxy QPA plasma concentrations and neutrophil count data from only study 1A, a PKPD model was developed and subsequently used to predict the MTD and a safe starting dose for the other trials., Results: The PKPD model based on data from the first study adequately described the time course of neutrophil count fluctuation. The two-stage model-based design provided safe starting doses for subsequent phase I trials for barasertib. Predicted safe starting dose levels were higher than those used in two subsequent trials, but lower than used in the other trial., Discussion: The two-stage approach could have been applied safely to define starting doses for alternative dosing strategies with barasertib. The limited improvement in efficiency for the phase I program of barasertib may have been due to the fact that starting doses for the studied phase I trials were already nearly optimal., Conclusion: Application of the two-stage model-based trial design in Phase I programs with novel anti-cancer drugs that cause haematological toxicity is feasible, safe, and may lead to a reduction in the number of patient treated at sub-therapeutic dose-levels.

What Is Known and Objective: Fluconazole is an antifungal agent that is commonly used to treat patients with serious systemic fungal infections in intensive care units. Fosfluconazole is a phosphate prodrug of fluconazole, which was developed to reduce the volume of fluid required to administer fluconazole by intravenous injection. The objective of this study was to characterize the pharmacokinetics of the antifungal fluconazole after the intravenous administration of the prodrug fosfluconazole or fluconazole in critically ill patients with serious systemic fungal infections, by population pharmacokinetic analysis using the nonmem software package., Methods: Clinical biochemical data including serum fluconazole levels were obtained from 57 patients treated in the intensive care unit along with two naïve pooled patients gleaned from previous reports. The pharmacokinetic model of fluconazole was estimated using a one-compartment model. The probability that the area under the concentration-time curve is higher than 800 μg h/mL was determined by simulation., Results: It was assumed that all the administered fosfluconazole was converted to fluconazole with an estimated fosfluconazole-fluconazole conversion rate constant of 2·05/h. The significant covariates for clearance for fluconazole (CL) and volume of distribution for fluconazole (Vd) were resulted in creatinine clearance (CLcr) and body weight (BW), respectively, in the final pharmacokinetic model equations: CL (L/h) = 0·799 × [CLcr (mL/min)/92·7](0·685) and Vd (L) = 48·1 × [BW (kg)/65](1·40) , where the interpatient variabilities in CL and Vd and the intrapatient variability were 44·8%, 79·7% and 19·8%, respectively. On the basis of the results of the Monte Carlo simulation, the probabilities of target attainment were 60%, 26% and 11% for 400 mg/day administration as fluconazole equivalent at CLcr values of 40, 70 and 100 mL/min, respectively., What Is New and Conclusion: The present population pharmacokinetic analysis strongly indicates that fosfluconazole (and fluconazole) dosage should be optimized in terms of CLcr in critically ill patients., (© 2011 Blackwell Publishing Ltd.)

Background and Purpose: Phospho-ibuprofen (P-I; MDC-917) inhibits the growth of colon cancer in mice. Here, we investigated the use of nanocarriers to improve its pharmacokinetics (PKs) and anti tumour efficacy., Experimental Approach: The cellular uptake and cytotoxicity of P-I encapsulated into liposomes and micelles, and its in vitro metabolic stability, were determined in cultures of human colon adenocarcinoma cells. The performance of liposomal P-I was further evaluated in PK studies in mice, and in a model of colon cancer xenografts in nude mice., Key Results: Liposomal P-I and micellar P-I showed significantly enhanced cellular uptake in the colon cancer cells. Liposomal P-I also demonstrated increased cytotoxicity in vitro. Free P-I was metabolized rapidly to ibuprofen in the presence of purified esterases. In contrast, liposomal P-I, and to a lesser extent micellar P-I, was resistant to esterase-mediated hydrolysis. In mice, liposomal P-I partially protected P-I from hydrolysis in the circulation, and improved the biodistribution of intact P-I and its metabolites compared to free P-I. Liposomal P-I was more effective at inhibiting the growth of human colon cancer xenografts in mice, which may be explained on the basis of its improved PK profile compared to free P-I., Conclusions and Implications: Liposome encapsulation of P-I partially protected P-I from esterase-mediated hydrolysis in mice, enhanced the cytotoxicity and bioavailability of P-I and increased its efficacy at inhibiting the growth of human colon cancer xenografts. These results indicate that liposomes are suitable nanocarriers for the delivery of P-I, and that the anti-tumour potential of liposomal P-I merits further evaluation., (© 2011 The Authors. British Journal of Pharmacology © 2011 The British Pharmacological Society.)

Purpose: To incorporate phospho-ibuprofen (P-I), a lipophilic, water insoluble novel anti-cancer agent, into pegylated liposomes and upon formulation optimization to evaluate its antitumor activity in vitro and in vivo., Methods: P-I loaded liposomes were prepared using the thin-film hydration method, and characterized for size, zeta potential, drug content and drug release. We examined their physical stability by particle size changes; their lyophilization ability in the presence of cryoprotectants; and their antitumor activity in vitro in human cancer cell lines and in vivo in a xenograft murine model., Results: P-I was successfully loaded into liposomes consisting of soy-PC and PEG(2000)-PE. These liposomes were <150 nm in diameter; exhibited prolonged stability in suspension and can be lyophilized using sucrose as cryoprotectant. P-I liposomes inhibited the growth of human cancer cell lines in vitro and in vivo of xenograft in nude mice to a greater extent than free P-I., Conclusions: High levels of P-I can be incorporated into liposomes which can be lyophilized in the presence of sucrose and showed good stability upon storage. Moreover, these drug-incorporating liposomes were capable of inhibiting the growth of xenografted tumors in mice more effectively than free P-I. These results justify further development of the P-I liposomes.

Purpose: This post hoc analysis investigated the hepatic safety profile of fosampre-navir (FPV) in patients monoinfected with HIV or coinfected with HIV and hepatitis B (HbsAg positive) and/or hepatitis C (anti-HCV antibody positive)., Methods: Data were pooled from 7 prospective, randomized clinical trials of FPV., Results: Baseline demographics were generally well-matched between the 205 coinfected (72% HCV, 24% HBV, 3% both) and 1,114 monoinfected patients in this analysis. At baseline, most regimens included ritonavir 100 mg (58%) or 200 mg (38%), and 73% of subjects were ART-naïve. Over 48 weeks, the rate of treatment-related serious adverse events was similar between the coinfected (8%; 16/205) and monoinfected (6%; 62/1114) groups, and the rate of treatment-related grade 2-4 adverse events was higher in the coinfected (38%; 77/205) compared with the monoinfected (29%; 320/1114) group. The percentage of patients with grade 3/4 liver enzyme elevations at any time through week 48 was 14% (ALT) and 12% (AST) in the coinfected group and 1% (both ALT and AST) in the monoinfected group. Median AST to platelet ratio index (APRI) scores decreased by 29% in both groups., Conclusion: Liver enzyme elevations in coinfected patients treated with FPV with or without ritonavir appear generally similar to those reported for other second-generation protease inhibitors.

Objective: oral sedation is the simplest and most convenient sedation method for managing uncooperative child patients because it is easy to administer and there is no need for nasal hood or injection. Oral midazolam is the most commonly used preanesthetic medication for children. When given in amounts between 0.5 and 0.75 mg/kg of body weight, oral midazolam has been found to be an effective sedative agent for pediatric outpatients. Tramadol is a synthetic, centrally acting analgesic indicated for moderate to severe pain. Chloral hydrate is one of the sedatives most commonly used, has excellent absorption, fast induction, and exert minimal effects on respiration. zolpidem is the most commonly prescribed hypnotic due to its clinical efficacy, safety, and ability to be well tolerated with patients., Materials and Methods: 60 anxious and fearful children who reported to the department were treated under conscious sedation for the accomplishment of dental treatment. Patients were randomly assigned to four groups. Statistical analysis was done using Kruskal Wallis Test and decision criterion was to reject the null hypothesis if the P-value is less than 0.05., Results: it was observed that there is a statistically significant difference in median scores recorded for the level of sedation between the different groups (P < 0.001)., Conclusion: this study concluded that midazolam is the best drug for producing conscious sedation followed by tramadol and triclofos. Zolpidem was not able to produce a sufficient level of sedation and it cannot be supported as a sedative agent at the present dosage.

In a retrospective database study at two HIV treatment centres, medical records were accessed to evaluate long-term efficacy and safety parameters in all HIV-infected adults who had achieved HIV-1 RNA <50 copies/mL following the initiation of fosamprenavir (FPV)/ritonavir (RTV) 1400 mg/100 mg once-daily (QD)-containing regimens between January 2004 and January 2006. Data were available for 20 antiretroviral (ARV)-naïve patients (baseline median HIV-1 RNA 5.0 log(10) copies/mL; CD4+ cell count 307 cells/mm(3)), 30 protease inhibitor (PI)-naïve, ARV-experienced patients (HIV-1 RNA 3.6 log(10) copies/mL; CD4+ count 348 cells/mm(3)) and 25 PI-experienced patients switching to FPV/RTV100 for reasons other than virological failure (HIV-1 RNA 2.7 log(10) copies/mL; CD4+ count 328 cells/mm(3)). HIV-1 RNA <50 copies/mL was achieved in 100% of the ARV-naïve cohort (median monitoring period, 2.4 years; range, 1.4-3.2 years), 87% of the PI-naïve cohort (2.4 years; range, 1.2-3.4 years) and 88% of the PI-experienced cohort (2.2 years; range, 1.0-3.2 years). Virological failure occurred in 0%, 7% and 8% of the cohorts, respectively, and median CD4+ count increased above baseline by 224, 155 and 115 cells/mm(3), respectively. Change from baseline in median fasting lipids was: total cholesterol +12, -6, -2 mg/dL; low-density lipoprotein-cholesterol 0, -5, +12 mg/dL; high-density lipoprotein-cholesterol +4, +2, +7 mg/dL; triglycerides +9, -21, -65 mg/dL, respectively. In conclusion, FPV/RTV 1400/100 mg QD-containing regimens remained effective long-term in all ARV-naïve and most PI-naïve and PI-experienced HIV-infected patients.