Enzyme-linked immunosorbent assay-based detection of free trenbolone in bovine bile

A rapid antibody-based detection system has been developed for the presence of free trenbolone in bovine samples. Polyclonal antibodies were produced that showed specificity toward epitopes located around the steroidal A-ring of the trenbolone molecule. These antibodies were shown to have little or no recognition for many closely related compounds. The antibodies were utilized as the specific biorecognition molecules in competitive and inhibitive enzyme-linked immunosorbent assay systems. While both assays were able to detect low nanogram concentrations of trenbolone in bovine bile, the competitive format was more sensitive (2.41 vs 17.15 ng/mL for TRAb2 and 3.31 vs 30.73 ng/mL for TRAb1). This format was also more accurate and the data produced by this assay fitted more closely to the four parameter equation used to calculate the standard curve. This was a common finding with both of the polyclonal antibodies, suggesting that this was a characteristic of the format used.     

Leaching of genetically modified Pseudomonas fluorescens through intact soil microcosms: Influence of soil type

Summary The leaching of a genetically modified Pseudomonas fluorescens through soil was investigated using intact (undisturbed) soil microcosms over a 2-month period. The microcosms comprised large cylindrical cores of three contrasting soil types (a loamy sand, a sandy loam, and a clay loam) supporting a grass/clover sward. Late log-phase cells of Pseudomonas fluorescens containing lux genes encoding for bioluminescence were applied to the surface of the soil cores. Eighteen hours after application of the inocula, the microcosms were subjected to simulated rain events (9 mm per event) at 3-day intervals and leachates were analysed for the concentration of genetically modified bacteria. The lux-modified pseudomonads were detected immediately in leachate from the clay looam with a steady decline in the concentration of cells with time. Leaching of pseudomonads from the sandy loam and loamy sand only occurred over a few rain events and total recoveries from the leachate were lower than from the clay loam. Leaching patterns are discussed in relation to differences in structure of topsoil and subsoil, which determine the pathways of water flow, and to the matric potential at inoculation, which determines the pore-size classes into which cells were first introduced.     

No alternative? The politics and history of non-GMO certification

Third-party certification is an increasingly prevalent tactic which agrifood activists use to “help” consumers shop ethically, and also to reorganize commodity markets. While consumers embrace the chance to “vote with their dollar,” academics question the potential for labels to foster widespread political, economic, and agroecological change. Yet, despite widespread critique, a mounting body of work appears resigned to accept that certification may be the only option available to activist groups in the context of neoliberal socio-economic orders. At the extreme, Guthman (Antipode 39(3): 457, 2007) posits that “at this political juncture… ‘there is no alternative.” This paper offers a different assessment of third-party certification, and points to interventions that are potentially more influential that are currently available to activist groups. Exploring the evolution of the Non-GMO Project—a novel certification for foods that are reasonably free of genetically engineered (GE) material—I make two arguments. First, I echo the literature’s critical perspective by illustrating how certification projects become vulnerable to industry capture. Reviewing its history and current context, I suggest that the Non-GMO Project would be better suited to helping companies avoid mounting public criticism than to substantially reorient agrifood production. Second, I explore the “politics of the possible” in the current political economy and argue that while neoliberalization and organizers’ places within the food system initially oriented the group towards the private sector, the choice to pursue certification arose directly from two industry partnerships. Consequently, current trends might favor market mechanisms, but certification is only one possible intervention that has emerged as a result of particular, and perhaps avoidable, circumstances. The article offers tentative delineation of alternatives ways that activists might intervene in agrifood and political economic systems given present constraints.     

Urinary tract manifestations of protothecosis in dogs

Records of 13 dogs with systemic infection with Prototheca sp. from 3 veterinary teaching hospitals were reviewed. Acute renal failure secondary to disseminated infection with Prototheca zopfii was diagnosed in 2 dogs. In 1 dog, acute renal failure developed during administration of immunosuppressive drugs for treatment of anterior uveitis. During diagnostic evaluation of this dog, Prototheca sp. organisms were noted in urine sediment and renal biopsy specimens. In the 2nd dog, acute renal failure was diagnosed after treatment for bacterial cystitis. After diagnosis of protothecosis, organisms were successfully isolated by aerobic urine culture. Both dogs with acute renal failure did not respond to conventional medical therapy. In total, Prototheca sp. was noted in urine sediment in 4 of 8 dogs and successfully cultured from urine in 5 of 7 dogs. Four of 5 dogs had organisms noted in the kidneys on histopathologic examination. In all dogs, the species identified was P zopfii. Sensitivity testing of 3 isolates revealed wide differences in in vitro drug resistance. Examination and culture of urine is recommended as a practical method for diagnosis of systemic infection with Prototheca sp.