Cypermethrin inhibits egg development in the ixodid tick, Amblyomma hebraeum

The pyrethroid insecticide, cypermethrin (CyM), stimulates vitellogenesis in Ornithodoros moubata (an argasid tick) by stimulating the release of the normal vitellogenesis-inducing factor (a neuropeptide) and subsequent release of the vitellogenic hormone [19]. Here we examine the effects of CyM on egg development in the ixodid tick, Amblyomma hebraeum. Ovary weight, oocyte size, and vitellin content of the ovary were measured after CyM treatment; in partially fed ticks, none of these parameters were affected significantly. However, CyM treatment caused an inhibition of ovary development, as well as reduction of both hemolymph 20-hydroxyecdysone (20E; the vitellogenic hormone in this species) and vitellogenin (Vg)-concentrations in engorged ticks. In addition, the degree of salivary gland degeneration (which is triggered by 20E) was slightly reduced in CyM-treated engorged ticks. These results indicate that CyM acts differently in Amblyomma compared to Ornithodoros. Instead of stimulating vitellogenesis, CyM inhibits egg development perhaps in part as a result of inhibiting release of 20E.     

Microbial degradation of several acetamide,acylanilide, carbamate,toluidine and urea pesticides

Soil enrichment was used to isolate soil microorganisms capable of degrading isopropyl carbanilate (propham), 3′,4′-dichloropropionanilide (propanil), 3′-chloro-2-methyl-p-valerotoluidide (solan), and methyl 3,4-dichlorocarbanilate (swep) in a muck and a silty clay loam. Degradation of the pesticides in enrichment solutions, and by pure cultures of effective microbial isolates was demonstrated by the production of the corresponding aniline, chloride ion liberation and disappearance of the parent compound. Degradation products were identified by gas-liquid and thin-layer chromatography.Organisms isolated include Pseudomonas striata Chester, Achromobacter sp., Aspergillus ustus (Bain) Thorn and Church, A. versicolor (Vuill. Tirabaschi), Fusarium oxysporum Schlecht, F. solani (Martius) Appel and Wollenweber, Penicillium chrysogenum Thorn, P. janthinellum Biourge, P. rugulosum Thorn and Trichoderma viride Pers. Each organism demonstrated a unique substrate specificity and was capable of degrading other aniline-based pesticides of the acetamide, acylanilide, carbamate, toluidine and urea classes.     

Monitoring insecticide resistance in house flies (Diptera: Muscidae) from New York dairies

House flies were collected from dairies across New York state and the levels of resistance to seven insecticides were measured using standard laboratory assays with three to five diagnostic concentrations. The highest levels of resistance were found for tetrachlorvinphos, permethrin and cyfluthrin. Although levels of resistance to methomyl were somewhat lower, they were among the highest ever reported for field‐collected house flies. Resistance to pyrethrins was limited primarily to the lowest diagnostic concentration. House flies were susceptible to fipronil at all dairies, suggesting that this material would be highly effective for fly control. The levels of resistance were similar at all the dairies, irrespective of their insecticide use, suggesting substantial movement of flies between facilities. Relative to resistance levels found at New York dairies in 1987, resistance levels had increased for permethrin, were unchanged for tetrachlorvinphos and had decreased for dimethoate. To identify a single diagnostic concentration that could be used in the laboratory assays to assess accurately resistance levels in future studies, we carried out a ‘simulated’ field bioassay using formulated materials. A diagnostic concentration for each insecticide is proposed on the basis of a comparison of our bioassays. © 2001 Society of Chemical Industry     

Comparison of methods to assess dog owners' therapeutic compliance

Objective To compare different methods for assessing the compliance of veterinary clients administering medication to their dogs.
Procedure Thirty-one owners whose dogs were prescribed amoxycillin-clavulanate, twice and thrice daily, for a duration of five to seven days were recruited from three Sydney veterinary hospitals. Compliance was assessed by electronic monitoring devices, return medication counts, client self-reports and veterinarians' estimation of likely compliance.
Results Electronic monitoring showed owners administered on average 84% (range 7 to 104%) of prescribed medication to their dogs. Both return medication counts and client self-reports tended to overestimate therapeutic compliance when compared with electronic monitoring. When questioned, the majority of owners (71%) claimed perfect compliance with the prescribed regimen. No correlation was found between veterinarians' estimates of owner compliance and that assessed electronically.
Conclusion Electronic monitoring provided valuable information on dose timing and variation, but proved costly and difficult to employ in veterinary practice. Simplicity and low cost of return medication counts makes this method attractive for use in veterinary compliance studies. Client self-reports reliably detected some noncompliers and permitted identification of individual problems or errors. For practical purposes a combination of return medication counts and client self-reports may have merit in future veterinary compliance studies.     

Responses to the Standard for Exchange of Nonclinical Data (SEND) in non-US countries

The Standard for the Exchange of Nonclinical Data (SEND), adopted by the US FDA, is part of a set of regulations and guidances requiring the submission of standardized electronic study data for nonclinical and clinical data submissions. SEND is the nonclinical implementation of SDTM (Study Data Tabulation Model), the standard electronic format for clinical regulatory submissions to FDA. SEND, SDTM, and the associated Controlled Terminology have been developed by CDISC (Clinical Data Interchange Standards Consortium). In order to successfully implement SEND, interdisciplinary contributions between sponsors and CROs, need a model for task allocation. This is being undertaken by the Pharmaceutical Users Software Exchange (PhUSE). Because SEND is currently the preferred submission format of the US FDA only and will become required by it starting in December 2016, only American academic societies and companies are actively involved. An exception to this is the INHAND initiative, which leads the way in standardizing terminology for toxicological pathology. On the other hand, international globalization of other clinical and nonclinical practices is not feasible because there are substantial differences between the US and non-US countries in CRO involvement in drug development. Thus, non-US countries must consider and develop approaches to SEND that meet their needs. This paper summarizes the activities of the major organizations involved in SEND development and implementation, discusses the effective use of SEND, and details a compliance scheme (research material of the Showa University School of Medicine) illustrating how pharmaceutical companies can complete a large amount of work up to an FDA application with the effective utilization of CROs and solution providers.     

Comparison of Antral and Preantral Ovarian Follicle Populations Between Bos indicus and Bos indicus‐taurus Cows with High or Low Antral Follicles Counts

The objective was to compare populations of antral and pre‐antral ovarian follicles in Bos indicus and Bos indicus‐taurus cows with high and low antral follicle counts. Nelore (Bos indicus, n = 20) and Nelore X Angus (1/2 Bos indicus‐taurus, n = 20) cows were subjected to follicular aspiration without regard to the stage of their oestrous cycle (day of aspiration = D0) to remove all follicles ≥3 mm and induce growth of a new follicular wave. Ovaries were examined by ultrasonography on D4, D19, D34, D49 and D64, and antral follicles ≥3 mm were counted. Thereafter, cows were assigned to one of two groups: high or low antral follicular count (AFC, ≥30 and ≤15 antral follicles, respectively). After D64, ovaries were collected after slaughter and processed for histological evaluation. There was high repeatability in the numbers of antral follicles for all groups (range 0.77–0.96). The mean (±SD) numbers of antral follicles were 35 ± 9 (Bos indicus) and 38 ± 6 (Bos indicus‐taurus) for the high AFC group and 10 ± 3 (Bos indicus) and 12 ± 2 (Bos indicus‐taurus) follicles for the low AFC. The mean number of preantral follicles in the ovaries of Bos indicus‐taurus cows with high AFC (116 226 ± 83 156 follicles) was greater (p < 0.05) than that of Bos indicus cows (63 032 ± 58 705 follicles) with high AFC. However, there was no significant correlation between numbers of antral and preantral follicles.