Developmental toxicity in embryo-larval zebrafish (Danio rerio) exposed to strobilurin fungicides (azoxystrobin and pyraclostrobin).

Azoxystrobin and pyraclostrobin are broad spectrum strobilurin fungicides that have been measured in the aquatic environment. Strobilurins inhibit mitochondrial respiration by binding to the mitochondrial respiratory complex III. The goal of this study was to investigate mitochondrial dysfunction and oxidative stress in the developing zebrafish from exposure to azoxystrobin and pyraclostrobin. Exposure studies were performed where zebrafish embryos were exposed to azoxystrobin and pyraclostrobin at 0.1, 10, 100 µg/L from 4 hpf to 48 hpf to measure mitochondrial dysfunction and oxidative stress mRNA transcripts, and 5 dpf to measure movement, growth, oxygen consumption, enzymatic activities, and mRNA transcripts. Results from this study indicated that there was a significant reduction in both basal and maximal respiration at 48 hpf in zebrafish exposed to 100 µg/L of pyraclostrobin. There was no difference in oxidative stress or apoptotic mRNA transcripts at 48 hpf, indicating that the two strobilurins were acting first on mitochondrial function and not directly through oxidative stress. At 5 dpf, standard body length was significantly reduced with exposure to pyraclostrobin and azoxystrobin exposure as compared to the control. These reductions in apical endpoints corresponded with increases in oxidative stress and apoptotic mRNA transcripts in treatment groups at 5 dpf indicating that strobilurins' exposure followed the adverse outcome pathway for mito-toxicants. Our results indicate that strobilurins can decrease mitochondrial function, which in turn lead to diminished growth and movement.

Comparative Lipid Peroxidation and Apoptosis in Embryo-Larval Zebrafish Exposed to 3 Azole Fungicides, Tebuconazole, Propiconazole, and Myclobutanil, at Environmentally Relevant Concentrations.

Azole fungicides have entered the aquatic environment through agricultural and residential runoff. In the present study, we compared the off-target toxicity of tebuconazole, propiconazole, and myclobutanil using embryo-larval zebrafish as a model. The aim of the present study was to investigate the relative toxicity of tebuconazole, propiconazole, and myclobutanil using multiple-level endpoints such as behavioral endpoints and enzymatic and molecular biomarkers associated with their mode of action. Zebrafish embryos were exposed to azoles at environmentally relevant and high concentrations, 0.3, 1.0, and 1000 µg/L, starting at 5 h postfertilization (hpf) up to 48 hpf, as well as 5 d postfertilization (dpf). Relative mRNA expressions of cytochrome P450 family 51 lanosterol-14α-demethylase, glutathione S-transferase, caspase 9, phosphoprotein p53, and BCL2-associated X protein were measured to assess toxicity attributable to fungicides at the mRNA level, whereas caspase 3/7 (apoptosis) and 3,4-methylene​dioxy​amphetamine (lipid peroxidation) levels were measured at the enzymatic level. Furthermore, mitochondrial dysfunction was measure through the Mito Stress test using the Seahorse XFe24 at 48 hpf. In addition, light to dark movement behavior was monitored at 5 dpf using Danio Vision® to understand adverse effects at the organismal level. There was no significant difference in the light to dark behavior with exposure to azoles compared to controls. The molecular biomarkers indicated that propiconazole and myclobutanil induced lipid peroxidation, oxidative stress, and potentially apoptosis at environmentally relevant concentrations (0.3 and 1 µg/L). The results from the mitochondrial respiration assay indicated a slight decrease in spare respiratory capacity with an acute exposure (48 hpf) to all 3 azoles at 1000 µg/L. Based on the present results, propiconazole and myclobutanil are acutely toxic compared to tebuconazole in aquatic organisms at environmentally relevant concentrations. Environ Toxicol Chem 2019;38:1455-1466. © 2019 SETAC.

Next step in antibiotic stewardship: Pharmacist-provided penicillin allergy testing.

WHAT IS KNOWN: Penicillin allergy limits therapeutic options for patients but often disappears over time, leaving patients erroneously labelled allergic and leading to the utilization of broad-spectrum and more expensive antibiotics. Penicillin allergy can be effectively assessed via skin testing. OBJECTIVE: To improve patient access to penicillin allergy testing by implementing a pharmacist-provided service in a hospital setting. COMMENT: Beta-lactams remain a mainstream therapy for many infections due to their effectiveness, low side effects and affordability. Typically, patient access to penicillin allergy testing is limited by the availability of allergy specialists, who traditionally perform such testing. A pharmacist-provided penicillin allergy testing service was implemented at our hospital in 2015 and became a powerful antibiotic stewardship tool. Removing penicillin allergy from patient profiles significantly expanded therapeutic options, expedited discharges and reduced costs of care. WHAT IS NEW: Pharmacists can expand patient access to penicillin allergy testing. CONCLUSION: Pharmacist-provided penicillin allergy testing permitted optimized antibiotic treatment and expedited discharges.

Assessing bioavailability of DDT and metabolites in marine sediments using solid-phase microextraction with performance reference compounds.

Solid-phase microextraction (SPME) has often been used to estimate the freely dissolved concentration (Cfree ) of organic contaminants in sediments. A significant limitation in the application of SPME for Cfree measurement is the requirement for attaining equilibrium partition, which is often difficult for strongly hydrophobic compounds such as DDT. A method was developed using SPME with stable isotope-labeled analogues as performance reference compounds (PRCs) to measure Cfree of DDT and metabolites (DDTs) in marine sediments. Six (13) C-labeled or deuterated PRCs were impregnated into polydimethylsiloxane (PDMS) fiber before use. Desorption of PRCs from PDMS fibers and absorption of DDTs from sediment were isotropic in a range of sediments evaluated ex situ under well-mixed conditions. When applied to a historically contaminated marine sediment from a Superfund site, the PRC-SPME method yielded Cfree values identical to those found by using a conventional equilibrium SPME approach (Eq-SPME), whereas the time for mixing was reduced from 9 d to only 9 h. The PRC-SPME method was further evaluated against bioaccumulation of DDTs by Neanthes arenaceodentata in the contaminated sediment with or without amendment of activated carbon or sand. Strong correlations were consistently found between the derived equilibrium concentrations on the fiber and lipid-normalized tissue residues for DDTs in the worms. Results from the present study clearly demonstrated the feasibility of coupling PRCs with SPME sampling to greatly shorten sampling time, thus affording much improved flexibility in the use of SPME for bioavailability evaluation.

The reliability of the wolf motor function test for assessing upper extremity function after stroke.

OBJECTIVE: To examine the reliability of the Wolf Motor Function Test (WMFT) for assessing upper extremity motor function in adults with hemiplegia. DESIGN: Interrater and test-retest reliability. SETTING: A clinical research laboratory at a university medical center. PATIENTS: A sample of convenience of 24 subjects with chronic hemiplegia (onset >1yr), showing moderate motor impairment. INTERVENTION: The WMFT includes 15 functional tasks. Performances were timed and rated by using a 6-point functional ability scale. The WMFT was administered to subjects twice with a 2-week interval between administrations. All test sessions were videotaped for scoring at a later time by blinded and trained experienced therapists. MAIN OUTCOME MEASURE: Interrater reliability was examined by using intraclass correlation coefficients and internal consistency by using Cronbach's alpha. RESULTS: Interrater reliability was.97 or greater for performance time and.88 or greater for functional ability. Internal consistency for test 1 was.92 for performance time and.92 for functional ability; for test 2, it was.86 for performance time and.92 for functional ability. Test-retest reliability was.90 for performance time and.95 for functional ability. Absolute scores for subjects were stable over the 2 test administrations. CONCLUSION: The WMFT is an instrument with high interrater reliability, internal consistency, test-retest reliability, and adequate stability.

Constraint-induced movement therapy for motor recovery after stroke.

A new therapeutic approach to rehabilitation of movement after stroke, termed Constraint-Induced (CI) Movement Therapy, has been derived from basic research with monkeys given somatosensory deafferentation. CI consists of a family of therapies; their common element is that they induce stroke patients to greatly increase the use of a more affected upper extremity for many hours a day over a 10-14 consecutive-day period. These therapies have significantly improved quality of movement and substantially increased amount of use of a more affected extremity in the activities of daily living in the life situation. The purpose of this paper is to describe the protocol used by the investigative team that developed the family of CI therapies and examined them as an effective rehabilitation approach.

Analysis of the effectiveness of in-office and transtelephonic follow-up in terms of pacemaker system complications.

A study was undertaken to determine the most effective method of pacemaker follow-up in terms of the total number of complications detected and yield per follow-up in single and dual chamber pacing systems. The analysis involved 9,786 patient records from 635 patients. The records were reviewed with respect to method of follow-up, number of chambers paced, and complications detected. Complications included: oversensing, undersensing, noncapture, pocket and diaphragmatic stimulation, pacemaker mediated tachycardia, crosstalk, pulse generator malfunction, lead malfunction, infection/erosion, premature end of service, exit block, and other miscellaneous problems. Eight thousand two hundred eighty-eight of the 9,786 follow-ups were performed in the office while 1,498 were transtelephonic. Single chamber pacing systems were implanted in 329 patients and 306 were dual chamber systems. A total of 599 complications were detected. Analysis yielded a per patient complication rate of 5.1% (single chamber) and 8.4% (dual chamber) for in-office follow-up. This compared to a transtelephonic follow-up per patient complication rate of only 0.3% (single chamber) and 1.0% (dual chamber). In-office pacemaker follow-up is significantly more effective (P < 0.001) than transtelephonic follow-up in detecting both single and dual chamber pacemaker system complications.

An operant approach to rehabilitation medicine: overcoming learned nonuse by shaping.

A new approach to the rehabilitation of movement, based primarily on the principles of operant conditioning, was derived from research with deafferented monkeys. The analysis suggests that a certain proportion of excess motor disability after certain types of injury involves a learned suppression of movement and may be termed learned nonuse. Learned nonuse can be overcome by changing the contingencies of reinforcement so that they strongly favor use of an affected upper extremity in the chronic postinjury situation. The techniques employed here involved 2 weeks of restricting movement of the opposite (unaffected) extremity and training of the affected limb. Initial work with humans has been with chronic stroke patients for whom the approach has yielded large improvements in motor ability and functional independence. We report here preliminary data suggesting that shaping with verbal feedback further enhances the motor recovery.

Technique to improve chronic motor deficit after stroke.

The unaffected upper extremity of chronic stroke patients was restrained in a sling during waking hours for 14 days; on ten of those days, these patients were given six hours of practice in using the impaired upper extremity. An attention-comparison group received several procedures designed to focus attention on use of the impaired upper extremity. The restraint subjects improved on each of the laboratory measures of motor function used--in most cases markedly. Extensive improvement, from a multi-year plateau of greatly impaired motor function, was also noted for the restraint group in the life situation and these gains were maintained during a two-year period of follow-up. For the comparison group only one measure showed small to moderate improvement, and this was lost during the follow-up period; there was essentially no overlap between the individuals of the two groups. Thus, prolonged restraint of an unaffected upper extremity and practice of functional movements with the impaired limb proved to be an effective means of restoring substantial motor function in stroke patients with chronic motor impairment identified by the inclusion criteria of this project.