Synergistic Effects of Earthworms and Plants on Chromium Removal from Acidic and Alkaline Soils: Biological Responses and Implications.

Soil heavy metal pollution has become one of the major environmental issues of global concern and solving this problem is a major scientific and technological need for today's socio-economic development. Environmentally friendly bioremediation methods are currently the most commonly used for soil heavy metal pollution remediation. Via controlled experiments, the removal characteristics of chromium from contaminated soil were studied using earthworms (Eisenia fetida and Pheretima guillelmi) and plants (ryegrass and maize) at different chromium concentrations (15 mg/kg and 50 mg/kg) in acidic and alkaline soils. The effects of chromium contamination on biomass, chromium bioaccumulation, and earthworm gut microbial communities were also analyzed. The results showed that E. fetida had a relatively stronger ability to remove chromium from acidic and alkaline soil than P. guillelmi, and ryegrass had a significantly better ability to remove chromium from acidic and alkaline soil than maize. The combined use of E. fetida and ryegrass showed the best effect of removing chromium from contaminated soils, wih the highest removal rate (63.23%) in acidic soil at low Cr concentrations. After soil ingestion by earthworms, the content of stable chromium (residual and oxidizable forms) in the soil decreased significantly, while the content of active chromium (acid-extractable and reducible forms) increased significantly, thus promoting the enrichment of chromium in plants. The diversity in gut bacterial communities in earthworms decreased significantly following the ingestion of chromium-polluted soil, and their composition differences were significantly correlated with soil acidity and alkalinity. Bacillales, Chryseobacterium, and Citrobacter may have strong abilities to resist chromium and enhance chromium activity in acidic and alkaline soils. There was also a significant correlation between changes in enzyme activity in earthworms and their gut bacterial communities. The bacterial communities, including Pseudomonas and Verminephrobacter, were closely related to the bioavailability of chromium in soil and the degree of chromium stress in earthworms. This study provides insights into the differences in bioremediation for chromium-contaminated soils with different properties and its biological responses.

Assessment of prior opioid tolerance among new users of fentanyl transdermal system in FDA's Sentinel System.

PURPOSE: Fentanyl transdermal system (FTS) is intended only for patients with prior opioid tolerance. The purpose of this study is to identify the proportion of new FTS users who had evidence of prior opioid tolerance, by dosage strength, in FDA's Sentinel System. METHODS: We identified new FTS episodes (183-day washout) from 2009 through 2013. Members were <65 years and enrolled in medical and pharmacy coverage for 183 days prior to initial FTS dispensing (index). We assessed the proportion of users with prior tolerance stratified by dosage strength of FTS using four definitions of opioid tolerance: ≥30-mg oxycodone equivalents/day in each of 7 consecutive days immediately prior to index; ≥30-mg oxycodone equivalents/day for any 7 days in the 30 days prior to index (secondary); any dose in each of 7 days in the 7 consecutive days immediately prior to index (tertiary); and any dose for any 7 days in the 30 days prior to index (quaternary). RESULTS: Of 44 450 episodes of 25 mcg/hr FTS, 37% met the primary definition, and 77% met the quaternary definition. Of 3507 episodes of 100 mcg/hr FTS, 57% and 74% met the primary and quaternary definitions, respectively. Those aged 25 to 34 years had the highest proportion of episodes with prior tolerance; those aged 55 to 64 accounted for more of the episodes overall. CONCLUSIONS: In Sentinel, many new users of FTS did not have evidence of prior opioid tolerance by the primary definition, ie, the product label definition, which is the minimum standard for the lowest FTS dose (12 mcg/hr), especially at the highest strength (100 mcg/hr). Validation of this metric is warranted, but our findings suggest the need for further prescriber education regarding appropriate prescribing of FTS.

Opioid tolerance and urine drug testing among initiates of extended-release or long-acting opioids in Food and Drug Administration's Sentinel System.

OBJECTIVE: A risk evaluation and mitigation strategy for extended-release and long-acting (ER/LA) opioid analgesics was approved by the Food and Drug Administration in 2012. Our objective was to assess frequency of opioid tolerance and urine drug testing for individuals initiating ER/LA opioid analgesics. DESIGN: Retrospective cohort study. SETTING: Sentinel, a distributed database with electronic healthcare data on >190 million predominantly commercially insured members. PATIENTS, PARTICIPANTS: Members under age 65 initiating ER/LA opioid analgesics between January 2009 and December 2013. MAIN OUTCOME MEASURE(S): We examined the proportion of opioid-tolerant-only ER/LA opioid analgesic initiates meeting tolerance criteria: receipt of ≥30 mg oxycodone equivalents per day in 7 days prior to the first opioid-tolerant-only dispensing. We separately examined the proportion of new users of extended-release oxycodone (ERO) and other ER/LA opioid analgesics with a claim for a urine drug test in the 30 days prior to, and separately for the 183 days after, dispensing. RESULTS: We identified 79,824 ERO, 7,343 extended-release hydromorphone, and 91,778 transdermal fentanyl opi-oid-tolerant-only episodes. Tolerance criteria were met in 64 percent of ERO, 64 percent of extended-release hydromorphone and 40 percent of transdermal fentanyl episodes. We identified 210,581 incident ERO and 311,660 other ER/LA opioid analgesic episodes. Use of urine drug testing for ERO compared with other ER/LA opioid analgesics was: 4 percent vs 14 percent respectively in the 30 days prior to initiation and 9 percent vs 23 percent respectively in the 183 days following initiation. CONCLUSIONS: These results suggest potential areas for improving appropriate ER/LA opioid analgesic prescribing practices.

Principles of economics crucial to pharmacy students' understanding of the prescription drug market.

Many pharmacy schools have increased the amount of economics coursework to which pharmacy students are exposed in their prepharmacy and pharmacy curriculums. Students obtain competencies aimed at understanding the basic concepts of microeconomic theory, such as supply and demand. However, pharmacy students often have trouble applying these principles to real world pharmaceuticals or healthcare markets. Our objective is to make economics more relevant for pharmacy students. Specifically, we detail and provide pharmacy-relevant examples of the effects of monopoly power, barriers to marketplace entry, regulatory environment, third party insurance, information asymmetry and unanticipated changes in the marketplace on the supply and demand for pharmaceuticals and healthcare services.

Cost-of-illness studies : a review of current methods.

The number of cost-of-illness (COI) studies has expanded considerably over time. One outcome of this growth is that the reported COI estimates are inconsistent across studies, thereby raising concerns over the validity of the estimates and methods. Several factors have been identified in the literature as reasons for the observed variation in COI estimates. To date, the variation in the methods used to calculate costs has not been examined in great detail even though the variations in methods are a major driver of variation in COI estimates. The objective of this review was to document the variation in the methodologies employed in COI studies and to highlight the benefits and limitations of these methods. The review of COI studies was implemented following a four-step procedure: (i) a structured literature search of MEDLINE, JSTOR and EconLit; (ii) a review of abstracts using pre-defined inclusion and exclusion criteria; (iii) a full-text review using pre-defined inclusion and exclusion criteria; and (iv) classification of articles according to the methods used to calculate costs. This review identified four COI estimation methods (Sum_All Medical, Sum_Diagnosis Specific, Matched Control and Regression) that were used in categorising articles. Also, six components of direct medical costs and five components of indirect/non-medical costs were identified and used in categorising articles.365 full-length articles were reflected in the current review following the structured literature search. The top five cost components were emergency room/inpatient hospital costs, outpatient physician costs, drug costs, productivity losses and laboratory costs. The dominant method, Sum_Diagnosis Specific, was a total costing approach that restricted the summation of medical expenditures to those related to a diagnosis of the disease of interest. There was considerable variation in the methods used within disease subcategories. In several disease subcategories (e.g. asthma, dementia, diabetes mellitus), all four estimation methods were represented, and in other cases (e.g. HIV/AIDS, obesity, stroke, urinary incontinence, schizophrenia), three of the four estimation methods were represented. There was also evidence to suggest that the strengths and weaknesses of each method were considered when applying a method to a specific illness. Comparisons and assessments of COI estimates should consider the method used to estimate costs both as an important source of variation in the reported COI estimates and as a marker of the reliability of the COI estimate.