[Occupational exposures among nurses caring for chemotherapy patients -Quantitative analysis of cyclophosphamide and α-fluoro-β-alanine in urine]

OBJECTIVES

The aim of this study was to measure the antineoplastic drug content in urine and verify the situation of occupational exposure of the antineoplastic drug among nurses who care for patients undergoing chemotherapy.

METHODS

Ten female nurses who were caring for patients receiving chemotherapy were the subjects of this study. Urine samples were collected over 24-hour periods, and each sample was analyzed. The excretion of cyclophosphamide (CP) and α-fluoro-β-alanine (FBAL) were measured in the urine of the 10 nurses. CP and FBAL were detected separately using gas chromatography tandem mass spectrometry (GC-MSMS) methods (Exposure Control, the Netherlands).

RESULT

CP was detected in 24 urine samples of 9 nurses. The total amount of CP excreted ranged from 5.4 to 44.2 ng/24-hours. The mean amount of CP excreted per nurse was 16.8 ng/24-hours. No significant difference was observed between the hospital I and II. FBAL was not detected in any of the urine samples. CP was detected in the urine of the nurses prior to their work shift. Moreover, CP was detected in the urine of the nurses who were not caring for patients in the intravenous drip of CP. There was most what answered that there was hair loss in health condition.

CONCLUSION

The results reveal that almost all nurses were exposed to cyclophosphamide. Even when the patient in the intravenous drip of CP was not being cared for, it became clear that exposure by CP existed. As the route of the exposure to CP, the inhalation or dermal absorption can be considered. To ensure minimum exposed to antineoplastic drugs, suitable personal protective equipment needs to be equipped also of various scenes of caring for chemotherapy patients. Moreover, it is important to keep an eye on the monitoring of the antineoplastic drug in the environment and a nurse's health condition periodically going forward.

How Anionic Vesicles Steer the Oligomerization of Enzymatically Oxidized p-Aminodiphenylamine (PADPA) toward a Polyaniline Emeraldine Salt (PANI-ES)-Type Product

The oxidation of the aniline dimer, p-aminodiphenylamine (PADPA), with Trametes versicolor laccase and O2 in an aqueous solution of pH 3.5 is controlled by negatively charged AOT (sodium bis(2-ethylhexyl) sulfosuccinate) vesicles. With vesicles, a product resembling polyaniline in its emeraldine salt form (PANI-ES) is obtained, in contrast to the reaction without vesicles where no such product is formed. To understand this observation, the product distribution and structures from the reaction with and without vesicles were determined by using partially selectively deuterated PADPA as a starting material and analyzing the products with HPLC-MS. We found that in the presence of vesicles the main product is obtained in about 50% yield, which is the N-C-para-coupled PADPA dimer that has spectroscopic properties of PANI-ES, as determined by time-dependent density functional theory (TD-DFT) calculations. A secondary reaction route leads to longer PADPA oligomers that must contain a phenazine core. Without vesicles, PADPA and its products undergo partial hydrolysis, but in the presence of vesicles, hydrolysis does not occur. Because molecular dynamics (MD) simulations show that the main intermediate oxidation product is embedded within the vesicle membrane, where the water content is very low, we propose that the microenvironment of the vesicle membrane protects the oxidation products from unwanted hydrolysis.

Urinary metabolomic profiling in mice with diet-induced obesity and type 2 diabetes mellitus after treatment with metformin, vildagliptin and their combination

Metformin, vildagliptin and their combination are widely used for the treatment of diabetes, but little is known about the metabolic responses to these treatments. In the present study, NMR-based metabolomics was applied to detect changes in the urinary metabolomic profile of a mouse model of diet-induced obesity in response to these treatments. Additionally, standard biochemical parameters and the expression of enzymes involved in glucose and fat metabolism were monitored. Significant correlations were observed between several metabolites (e.g., N-carbamoyl-β-alanine, N1-methyl-4-pyridone-3-carboxamide, N1-methyl-2-pyridone-5-carboxamide, glucose, 3-indoxyl sulfate, dimethylglycine and several acylglycines) and the area under the curve of glucose concentrations during the oral glucose tolerance test. The present study is the first to present N-carbamoyl-β-alanine as a potential marker of type 2 diabetes mellitus and consequently to demonstrate the efficacies of the applied antidiabetic interventions. Moreover, the elevated acetate level observed after vildagliptin administration might reflect increased fatty acid oxidation.

Effects of multiple ascending doses of the glucagon receptor antagonist PF-06291874 in patients with type 2 diabetes mellitus

AIMS

To assess the pharmacokinetics, pharmacodynamics, safety and tolerability of multiple ascending doses of the glucagon receptor antagonist PF-06291874 in patients with type 2 diabetes mellitus (T2DM).

METHODS

Patients were randomized to oral PF-06291874 or placebo on a background of either metformin (Part A, Cohorts 1-5: 5-150 mg once daily), or metformin and sulphonylurea (Part B, Cohorts 1-2: 15 or 30 mg once daily) for 14-28 days. A mixed-meal tolerance test (MMTT) was administered on days -1 (baseline), 14 and 28. Assessments were conducted with regard to pharmacokinetics, various pharmacodynamic variables, safety and tolerability. Circulating amino acid concentrations were also measured.

RESULTS

PF-06291874 exposure was approximately dose-proportional with a half-life of ∼19.7-22.7 h. Day 14 fasting plasma glucose and mean daily glucose values were reduced from baseline in a dose-dependent manner, with placebo-corrected decreases of 34.3 and 42.4 mg/dl, respectively, at the 150 mg dose. After the MMTT, dose-dependent increases in glucagon and total glucagon-like peptide-1 (GLP-1) were observed, although no meaningful changes were noted in insulin, C-peptide or active GLP-1 levels. Small dose-dependent increases in LDL cholesterol were observed, along with reversible increases in serum aminotransferases that were largely within the laboratory reference range. An increase in circulating gluconeogenic amino acids was also observed on days 2 and 14. All dose levels of PF-06291874 were well tolerated.

CONCLUSION

PF-06291874 was well tolerated, has a pharmacokinetic profile suitable for once-daily dosing, and results in reductions in glucose with minimal risk of hypoglycaemia.

(11)C-methylaminoisobutyric acid (MeAIB) PET for evaluation of prostate cancer: compared with (18)F-fluorodeoxyglucose PET

OBJECTIVE

α-N-methyl-(11)C-methylaminoisobutyric acid ((11)C-MeAIB) is a selective substrate of system A amino acid transport, and known to accumulate in malignant lesions. The aim of this study was to evaluate the utility of MeAIB PET for the assessment of prostate cancer, compared with FDG PET.

METHODS

Thirty-four men (age range 57-77 years) with prostate cancer were prospectively enrolled, and underwent MeAIB PET and FDG PET between January 2011 and January 2013. MeAIB PET and FDG PET were performed at 20 and 50 min post-injection, respectively. SUVmax of the prostate was calculated, and visual analysis was conducted for MeAIB and FDG PET studies. MRI images were visually evaluated if available. All patients received total prostatectomy subsequently, and imaging findings were compared with pathological results, including T stage, Gleason score, and tumor size. The patient-based and lesion-based sensitivity and specificity were calculated according to pathological significant cancer.

RESULTS

Mean value of SUVmax of (11)C-MeAIB PET and (18)F-FDG PET in prostate cancer were 3.18 (±1.90, range; 1.55-9.57) and 3.88 (±2.85, range; 2.04-14.47). MeAIB PET and FDG PET were positive by visual analysis in 47.1 % (16/34) and 44.1 % (15/34) of the patients. MRI was positive in 51.5 % (17/33). Pathological stage and Gleason score were as follows: Stage 2 (n = 23), 3 (n = 8), and 4 (n = 3); Gleason score 6 (n = 13), 7 (n = 16), 8 (n = 3), and 9 (n = 2). The sensitivities tended to be higher according to higher pathological T stage or Gleason sum score for both MeAIB and FDG PET studies. Visual analysis of both MeAIB PET and FDG PET had significant correlation with extraprostatic extension (p < 0.05). MeAIB PET and FDG PET had complementary results by visual analysis in the assessment of prostate cancer. The patient-based sensitivity of MeAIB PET, FDG PET, and MRI were 51.6, 48.4, and 56.7 %, respectively. The patient-based specificity of these modalities was 100 % for each modality.

CONCLUSIONS

MeAIB PET has better diagnostic results than FDG PET for the assessment of significant prostate cancer, and these PET studies showed complementary results. MRI has even better diagnostic results than (11)C-MeAIB PET. MeAIB accumulates in prostate cancer, which indicates that the system A amino acid transport pathway is activated in prostate cancer.

Visualization of conventional outflow tissue responses to netarsudil in living mouse eyes

Visual impairment due to glaucoma currently impacts 70 million people worldwide. While disease progression can be slowed or stopped with effective lowering of intraocular pressure, current medical treatments are often inadequate. Fortunately, three new classes of therapeutics that target the diseased conventional outflow tissue responsible for ocular hypertension are in the final stages of human testing. The rho kinase inhibitors have proven particularly efficacious and additive to current therapies. Unfortunately, non-contact technology that monitors the health of outflow tissue and its response to conventional outflow therapy is not available clinically. Using optical coherence tomographic (OCT) imaging and novel segmentation software, we present the first demonstration of drug effects on conventional outflow tissues in living eyes. Topical netarsudil (formerly AR-13324), a rho kinase/ norepinephrine transporter inhibitor, affected both proximal (trabecular meshwork and Schlemm's Canal) and distal portions (intrascleral vessels) of the mouse conventional outflow tract. Hence, increased perfusion of outflow tissues was reliably resolved by OCT as widening of the trabecular meshwork and significant increases in cross-sectional area of Schlemm's canal following netarsudil treatment. These changes occurred in conjunction with increased outflow facility, increased speckle variance intensity of outflow vessels, increased tracer deposition in conventional outflow tissues and decreased intraocular pressure. This is the first report using live imaging to show real-time drug effects on conventional outflow tissues and specifically the mechanism of action of netarsudil in mouse eyes. Advancements here pave the way for development of a clinic-friendly OCT platform for monitoring glaucoma therapy.

Diaminopropionic Acid Reinforced Graphene Sponge and Its Use for Hemostasis

2,3-Diaminopropionic acid (DapA), a medicinal amino acid, is used for the first time to prepare a DapA cross-linked graphene sponge (DCGS) for hemostasis treatment. In a comparison with the reported ethanediamine (EDA) cross-linked graphene sponge (CGS), this carboxyl-functionalized DCGS can not only quickly absorb plasma, but also stimulate erythrocytes and platelets to change their normal form and structure at the interface, which largely affects a cell's metabolism and biofunction, thus further promoting blood coagulation. Whole blood clotting and rat-tail amputation tests indicated that on the basis of the additional interfacial stimulation, the hemostatic efficiency of the DCGS has been significantly improved in comparison with that of the CGS control (P < 0.05). In-depth insight revealed that the increased oxidation degree and the negative charge density play the crucial rule in the enhanced hemostatic performance. The chiral effect contributes mainly to the selective adhesion of erythrocytes and platelets rather than practical hemostasis. Nevertheless, this presentation demonstrated that, on the premise of keeping the fast absorbability, this is an effective method to improve the hemostatic efficiency by enhancing the cell/graphene interface interaction.

Infodisruption of inducible anti-predator defenses through commercial insect repellents?

Commercial insect repellents like DEET (N,N-diethyl-m-toluamide), EBAAP (IR3535(®), (3-[N-butyl-N-acetyl]-aminopropionic acid, ethyl ester)) or Icaridine (picaridin, Bayrepel, 1-piperidinecarboxylic acid, 2-(2-hydroxyethyl), 1-methylpropyl ester) are used worldwide to protect against biting insects and ticks. The detection of these repellents in surface waters in concentrations up to several μg/L levels has caused concern that these substances might affect non-target organisms in freshwaters. Daphnia sp., a keystone organism in lakes and ponds, is known for diel vertical migration (DVM) and life-history changes (LHCs) as inducible defenses against predation by fish. Here we test whether (i) environmentally relevant concentrations of DEET, EBAPP or Icaridine have repellent effects on Daphnia magna and (ii) if these repellents are infodisruptors for DVM and LHCs. Using concentrations of up to 44 μg/L, the repellents neither had effects on juvenile somatic growth nor on clutch size. In thermally stratified water columns with a repellent-free hypolimnion, no repellent effects of the test compounds on D. magna were observed. The presence of fish-born infochemicals induced LHCs, which are characterized by a reduced size at first reproduction, and DVM in D. magna. These effects were not affected by the presence of either repellent. Hence no evidences for infodisruption of the chemical communication of fish and Daphnia by DEET, EBAAP or Icaridine were found.

Idarucizumab for Dabigatran Reversal

BACKGROUND

Specific reversal agents for non-vitamin K antagonist oral anticoagulants are lacking. Idarucizumab, an antibody fragment, was developed to reverse the anticoagulant effects of dabigatran.

METHODS

We undertook this prospective cohort study to determine the safety of 5 g of intravenous idarucizumab and its capacity to reverse the anticoagulant effects of dabigatran in patients who had serious bleeding (group A) or required an urgent procedure (group B). The primary end point was the maximum percentage reversal of the anticoagulant effect of dabigatran within 4 hours after the administration of idarucizumab, on the basis of the determination at a central laboratory of the dilute thrombin time or ecarin clotting time. A key secondary end point was the restoration of hemostasis.

RESULTS

This interim analysis included 90 patients who received idarucizumab (51 patients in group A and 39 in group B). Among 68 patients with an elevated dilute thrombin time and 81 with an elevated ecarin clotting time at baseline, the median maximum percentage reversal was 100% (95% confidence interval, 100 to 100). Idarucizumab normalized the test results in 88 to 98% of the patients, an effect that was evident within minutes. Concentrations of unbound dabigatran remained below 20 ng per milliliter at 24 hours in 79% of the patients. Among 35 patients in group A who could be assessed, hemostasis, as determined by local investigators, was restored at a median of 11.4 hours. Among 36 patients in group B who underwent a procedure, normal intraoperative hemostasis was reported in 33, and mildly or moderately abnormal hemostasis was reported in 2 patients and 1 patient, respectively. One thrombotic event occurred within 72 hours after idarucizumab administration in a patient in whom anticoagulants had not been reinitiated.

CONCLUSIONS

Idarucizumab completely reversed the anticoagulant effect of dabigatran within minutes. (Funded by Boehringer Ingelheim; RE-VERSE AD ClinicalTrials.gov number, NCT02104947.).

Metal coordination and tyrosinase inhibition studies with Kojic-βAla-Kojic

Kojic acid is a natural antifungal and antibacterial agent that has been extensively studied for its tyrosinase inhibitory and metal coordination properties. Tyrosinase is a metalloenzyme with two copper ions in the active site. It is widely accepted that the tyrosinase inhibitory activity of kojic acid is related to its ability to coordinate metals. Over the past five years, we have used kojic acid to synthesize new and efficient bis-kojic acid chelators of iron and aluminium. In parallel, we investigated whether the de novo designed ligands could interfere with proper tyrosinase functioning. The present study combines our experience with inhibition and coordination studies of the new ligand: Kojic-βAla-Kojic. Research aimed at the assembly of a new potent tyrosinase inhibitor was based on the well-known crystal structure of the enzyme. Two questions were whether two kojic acids could act better than one and to what extent the length and kind of linker could ameliorate metal coordination, and inhibitory activity. Our results show that Kojic-βAla-Kojic has high affinity for Fe(III), Al(III), Zn(II), and Cu(II) and strong tyrosinase inhibitory effect and it can be proposed for use in industrial and pharmaceutical applications.

Global coagulation tests: their applicability for measuring direct factor Xa- and thrombin inhibition and reversal of anticoagulation by prothrombin complex concentrate

BACKGROUND

Specific mass spectrometry and direct activated factor X (Xa)- and thrombin inhibition assays do not allow determination of the reversal of anticoagulant effects of non-vitamin K direct oral anticoagulants (NOACs) by prothrombin complex concentrate (PCC). The objective of this study was the evaluation of the applicability of a variety of commercially available global coagulation assays in analyzing the reversal of NOAC anticoagulation by PCC.

METHODS

Plasma and whole blood were spiked with apixaban or dabigatran and PCC was added to these samples. Prothrombin time (PT), modified PT (mPT), activated partial prothrombin time (APTT), thrombography (CAT method) and thromboelastography (ROTEM, TEG) were performed.

RESULTS

Assays triggered by contact activation (APTT, INTEM) did not show inhibitor reversal by PCC. Assays triggered by tissue factor (TF) showed NOAC type and NOAC concentration dependent anticoagulation reversal effects of PCC ranging from partial normalization to overcorrection of the following parameters: clotting or reaction time (PT, mPT TEG-TF, EXTEM, FIBTEM); angle in thromboelastography (TEG-TF); thrombin generation (CAT) lag time, endogenous thrombin potential (ETP) and peak thrombin. Extent of reversal was assay reagent dependent. ETP (5 pM TF) was the only parameter showing complete reversal of anticoagulation by PCC for all NOACs ranging from 200 to 800 μg/L.

CONCLUSIONS

ETP fits with the concept that reversal assessment of NOAC anticoagulation by PCC should be based on measurements on the clotting potential or thrombin generating potential of the plasma or whole blood patient sample. Low sensitivity of ETP for NOACs and its correlation with bleeding are issues that remain to be resolved.

Dabigatran (Pradaxa): deep vein thrombosis and pulmonary embolism. Warfarin remains the standard drug

Not more effective than warfarin in three "non-inferiority" trials. Less bleeding but more acute coronary events with dabigatran, and still no antidote.

Fumigant Toxicity of Phenylpropanoids Identified in Asarum sieboldii Aerial Parts to Lycoriella ingenua (Diptera: Sciaridae) and Coboldia fuscipes (Diptera: Scatopsidae)

Lycoriella ingenua (Dufour) (Diptera: Sciaridae) and Coboldia fuscipes (Meigen) (Diptera: Scatopsidae) are two of the most economically important insect pests of cultivated mushrooms. The toxicities to the fly larvae of the three phenylpropanoids (methyleugenol, myristicin, and safrole) from aerial parts of Asarum sieboldii Miquel (Aristolochiaceae) were compared with those of the currently available carbamate insecticide benfuracarb. In a contact+fumigant mortality bioassay with L. ingenua and C. fuscipes larvae, methyleugenol (1.46 and 2.33 µg/cm2) was the most toxic compound, followed by safrole (2.03 and 2.59 µg/cm2) and myristicin (3.59 and 4.96 µg/cm2), based on 24-h LC50 values. The phenylpropanoids were less toxic than benfuracarb (LC50, 0.75 and 0.55 µg/cm2). In vapor-phase mortality tests with the larvae, the phenylpropanoids were consistently more toxic in closed versus open containers, indicating that the effect of the compounds was largely a result of vapor action. Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on A. sieboldii plant-derived products as potential fumigants for the control of mushroom fly populations in mushroom houses and mushroom compost.

Determination of β-N-oxalyl-L-α,β-diaminopropionic acid and homoarginine in Lathyrus sativus and Lathyrus cicera by capillary zone electrophoresis

BACKGROUND

Lathyrus species as legumes represent an alternative protein source for human and animal nutrition. Heavy consumption of these species can lead to lathyrism, caused by the non-protein amino acid β-N-oxalyl-l-α,β-diaminopropionic acid (β-ODAP). Currently, there is no well-defined level below which β-ODAP is considered non-toxic. In this work, the β-ODAP content was determined in L. sativus and L. cicera samples to assess their potential toxicity. Homoarginine is another non-protein amino acid found in Lathyrus spp. with interesting implications for human and animal nutrition.

RESULTS

The level of β-ODAP found in these two species ranged from 0.79 to 5.05 mg g(-1). The homoarginine content of the samples ranged from 7.49 to 12.44 mg g(-1).

CONCLUSION

This paper describes an accurate, fast and sensitive method of simultaneous detection and quantification of β-ODAP and homoarginine by capillary zone electrophoresis in L. cicera and L. sativus seeds. Moreover, several methods of extraction were compared to determine the highest performance.

Risk of gastrointestinal bleeding associated with oral anticoagulants: population based retrospective cohort study

OBJECTIVES

To determine the real world safety of dabigatran or rivaroxaban compared with warfarin in terms of gastrointestinal bleeding.

DESIGN

Retrospective cohort study.

SETTING

Large administrative database of commercially insured people in United States from 1 October 2010 through 31 March 2012.

PARTICIPANTS

Enrollees with a prescription of warfarin, dabigatran, or rivaroxaban between 1 October 2010 and 31 March 2012, who were aged 18 years or older, had continuous enrollment and no oral anticoagulant use during the six months before the entry date, with known age and sex, and with no gastrointestinal bleeding for at least six months before the cohort entry date. The final study sample of 46,163 patients included 4907 using dabigatran, 1649 using rivaroxaban, and 39,607 using warfarin.

MAIN OUTCOME MEASURE

Time to gastrointestinal bleeding. Hazard ratios were derived from Cox proportional hazard models with propensity score weighting and robust estimates of errors.

RESULTS

Dabigatran users tended to be older (dabigatran v rivaroxaban v warfarin: 62.0 v 57.6 v 57.4 years) and more likely to be male (69% v 49% v 53%). The rate of gastrointestinal bleeding was highest among dabigatran users and lowest among rivaroxaban users (dabigatran v rivaroxaban v warfarin: 9.01 v 3.41 v 7.02 cases per 100 person years). After adjustment for potentially confounding covariates, there was no evidence of a statistically significant difference in the risk of gastrointestinal bleeding between dabigatran and warfarin users (adjusted hazard ratio 1.21, 95% confidence interval 0.96 to 1.53) or between rivaroxaban and warfarin users (0.98, 0.36 to 2.69).

CONCLUSIONS

Although rates of gastrointestinal bleeding seem to be similar in this commercially insured sample of adults in the United States, we cannot rule out as much as a 50% increase in the risk of gastrointestinal bleeding with dabigatran compared with warfarin or a more than twofold higher risk of bleeding with rivaroxaban compared with warfarin.

Comparative risk of gastrointestinal bleeding with dabigatran, rivaroxaban, and warfarin: population based cohort study

OBJECTIVE

To determine the real world risk of gastrointestinal bleeding associated with the use of the novel oral anticoagulants dabigatran and rivaroxaban compared with warfarin.

DESIGN

Retrospective, propensity matched cohort study.

SETTING

Optum Labs Data Warehouse, a large database including administrative claims data on privately insured and Medicare Advantage enrollees.

PARTICIPANTS

New users of dabigatran, rivaroxaban, and warfarin from 1 November 2010 to 30 September 2013.

MAIN OUTCOME MEASURES

Incidence rates (events/100 patient years) and propensity score matched Cox proportional hazards models were used to estimate rates of total gastrointestinal bleeds, upper gastrointestinal bleeds, and lower gastrointestinal bleeds for the novel oral anticoagulants compared with warfarin in patients with and without atrial fibrillation. Heterogeneity of treatment effect related to age was examined using a marginal effects model.

RESULTS

The incidence of gastrointestinal bleeding associated with dabigatran was 2.29 (95% confidence interval 1.88 to 2.79) per 100 patient years and that associated with warfarin was 2.87 (2.41 to 3.41) per 100 patient years in patients with atrial fibrillation. In non-atrial fibrillation patients, the incidence of gastrointestinal bleeding was 4.10 (2.47 to 6.80) per 100 patient years with dabigatran and 3.71 (2.16 to 6.40) per 100 patient years with warfarin. With rivaroxaban, 2.84 (2.30 to 3.52) gastrointestinal bleeding events per 100 patient years occurred in atrial fibrillation patients (warfarin 3.06 (2.49 to 3.77)/100 patient years) and 1.66 (1.23 to 2.24) per 100 patient years in non-atrial fibrillation patients (warfarin 1.57 (1.25 to 1.99)/100 patient years). In propensity score matched models, the risk of gastrointestinal bleeding with novel oral anticoagulants was similar to that with warfarin in atrial fibrillation patients (dabigatran v warfarin, hazard ratio 0.79 (0.61 to 1.03); rivaroxaban v warfarin, 0.93 (0.69 to 1.25)) and in non-AF patients (dabigatran v warfarin, hazard ratio 1.14 (0.54 to 2.39); rivaroxaban v warfarin, 0.89 (0.60 to 1.32)). The risk of gastrointestinal bleeding increased after age 65, such that by age 76 the risk exceeded that with warfarin among atrial fibrillation patients taking dabigatran (hazard ratio 2.49 (1.61 to 3.83)) and patients with and without atrial fibrillation taking rivaroxaban (2.91 (1.65 to 4.81) and 4.58 (2.40 to 8.72), respectively).

CONCLUSIONS

The risk of gastrointestinal bleeding related to novel oral anticoagulants was similar to that for warfarin. Caution should be used when prescribing novel oral anticoagulants to older people, particularly those over 75 years of age.

Site-level variation in and practices associated with dabigatran adherence

IMPORTANCE

Unlike warfarin, which requires routine laboratory testing and dose adjustment, target-specific oral anticoagulants like dabigatran do not. However, optimal follow-up infrastructure and modifiable site-level factors associated with improved adherence to dabigatran are unknown.

OBJECTIVES

To assess site-level variation in dabigatran adherence and to identify site-level practices associated with higher dabigatran adherence.

DESIGN, SETTING, AND PARTICIPANTS

Mixed-methods study involving retrospective quantitative and cross-sectional qualitative data. A total of 67 Veterans Health Administration sites with 20 or more patients filling dabigatran prescriptions between 2010 and 2012 for nonvalvular atrial fibrillation were sampled (4863 total patients; median, 51 patients per site). Forty-seven pharmacists from 41 eligible sites participated in the qualitative inquiry.

EXPOSURE

Site-level practices identified included appropriate patient selection, pharmacist-driven patient education, and pharmacist-led adverse event and adherence monitoring.

MAIN OUTCOMES AND MEASURES

Dabigatran adherence (intensity of drug use during therapy) defined by proportion of days covered (ratio of days supplied by prescription to follow-up duration) of 80% or more.

RESULTS

The median proportion of patients adherent to dabigatran was 74% (interquartile range [IQR], 66%-80%). After multivariable adjustment, dabigatran adherence across sites varied by a median odds ratio of 1.57. Review of practices across participating sites showed that appropriate patient selection was performed at 31 sites, pharmacist-led education was provided at 30 sites, and pharmacist-led monitoring at 28 sites. The proportion of adherent patients was higher at sites performing appropriate selection (75% vs 69%), education (76% vs 66%), and monitoring (77% vs 65%). Following multivariable adjustment, association between pharmacist-led education and dabigatran adherence was not statistically significant (relative risk [RR], 0.94; 95% CI, 0.83-1.06). Appropriate patient selection (RR, 1.14; 95% CI, 1.05-1.25), and provision of pharmacist-led monitoring (RR, 1.25; 95% CI, 1.11-1.41) were associated with better patient adherence. Additionally, longer duration of monitoring and providing more intensive care to nonadherent patients in collaboration with the clinician improved adherence.

CONCLUSIONS AND RELEVANCE

Among nonvalvular atrial fibrillation patients treated with dabigatran, there was variability in patient medication adherence across Veterans Health Administration sites. Specific pharmacist-based activities were associated with greater patient adherence to dabigatran.

Economic process to co-produce poly(ε-l-lysine) and poly(l-diaminopropionic acid) by a pH and dissolved oxygen control strategy

This study tended to apply biorefinery of indigenous microbes to the fermentation of target-product generation through a novel control strategy. A novel strategy for co-producing two valuable homopoly(amino acid)s, poly(ε-l-lysine) (ε-PL) and poly(l-diaminopropionic acid) (PDAP), was developed by controlling pH and dissolved oxygen concentrations in Streptomyces albulus PD-1 fermentation. The production of ε-PL and PDAP got 29.4 and 9.6gL(-1), respectively, via fed-batch cultivation in a 5L bioreactor. What is more, the highest production yield (21.8%) of similar production systems was achieved by using this novel strategy. To consider the economic-feasibility, large-scale production in a 1t fermentor was also implemented, which would increase the gross profit of 54,243.5USD from one fed-batch bioprocess. This type of fermentation, which produces multiple commercial products from a unified process is attractive, because it will improve the utilization rate of raw materials, enhance production value and enrich product variety.