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Standardized terminology for the porcine reproductive and respiratory syndrome virus (PRRSV) status of swine herds is necessary to facilitate communication between veterinarians, swine producers, genetic companies, and other industry participants. It is also required for implementation of regional and national efforts towards PRRSV control and elimination. The purpose of this paper is to provide a herd classification system for describing the PRRSV status of herds, based upon a set of definitions reflecting the biology and ecology of PRRSV. The herd classification system was developed by a definitions committee formed jointly by the American Association of Swine Veterinarians (AASV) and the United States Department of Agriculture PRRS-Coordinated Agricultural Project, and was approved by the AASV Board of Directors on March 9, 2010. The committee included veterinarians from private practice and industry, researchers, and representatives from AASV and the National Pork Board. Breeding herds, with or without growing pigs on the same premises, are categorized as Positive Unstable (Category I), Positive Stable (Category II), Provisional Negative (Category III), or Negative (Category IV) on the basis of herd shedding and exposure status. Growing-pig herds are categorized as Positive or Negative. Recommended testing procedures and decision rules for herd classification are detailed.

Interferons (IFNs) regulate the expression of genes that mediate their antiviral, antitumor, and immunomodulatory actions. We have previously shown that IFN-beta suppresses growth of human ovarian carcinoma xenografts in vivo and induces apoptosis of ovarian carcinoma cells in vitro. To investigate mechanisms of IFN-beta-induced apoptosis we employed an antisense technical knockout approach to identify gene products that mediate cell death and have isolated several regulators of interferon-induced death (RIDs). In this investigation, we have characterized one of the RIDs, RID-2. Sequence analysis revealed that RID-2 was identical to human inositol hexakisphosphate kinase 2 (IP6K2). IP6K2 is post-transcriptionally induced by IFN-beta in ovarian carcinoma cells. A mutant IP6K2 with substitutions in the putative inositol phosphate binding domain abrogates IFN-beta-induced apoptosis. These studies identify a novel function for IP6K2 in cell growth regulation and apoptosis.

The effect on the polymerization kinetics of predissolving polystyrene polymers that have various molecular weights and end groups in styrene miniemulsions prepared using hexadecane as costabilizer was studied. It was noted that the rate of polymerization and number of droplets nucleated were affected by the molecular weight of the polymer that was predissolved. This dependence was attributed to a change in the number of droplets formed during homogenization as the molecular weight of the polymer was varied. However, the end group of the predissolved polymer did not have an affect on the kinetics. In all cases, predissolving polymer into a miniemulsion stabilized using hexadecane as costabilizer resulted in a much lower degree of enhancement in the kinetics compared to similar miniemulsion systems using cetyl alcohol as costabilizer. Since droplet sizes in miniemulsions containing hexadecane have been shown to be stable with time, unlike miniemulsions containing cetyl alcohol, these experiments were taken as evidence that the dominant cause for “enhanced droplet nucleation” is the preservation of droplet number prior to the addition of initiator.

Conventional nonsteroidal anti-inflammatory drugs inhibit both cyclooxygenase (Cox) isoforms (Cox-1 and Cox-2) and may be associated with nephrotoxicity. The present study was undertaken to assess the renal effects of the specific Cox-2 inhibitor, MK-966. Healthy older adults (n = 36) were admitted to a clinical research unit, placed on a fixed sodium intake, and randomized under double-blind conditions to receive the specific Cox-2 inhibitor, MK-966 (50 mg every day), a nonspecific Cox-1/Cox-2 inhibitor, indomethacin (50 mg t.i.d.), or placebo for 2 weeks. All treatments were well tolerated. Both active regimens were associated with a transient but significant decline in urinary sodium excretion during the first 72 h of treatment. Blood pressure and body weight did not change significantly in any group. The glomerular filtration rate (GFR) was decreased by indomethacin but was not changed significantly by MK-966 treatment. Thromboxane biosynthesis by platelets was inhibited by indomethacin only. The urinary excretion of the prostacyclin metabolite 2,3-dinor-6-keto prostaglandin F1alpha was decreased by both MK-966 and indomethacin and was unchanged by placebo. Cox-2 may play a role in the systemic biosynthesis of prostacyclin in healthy humans. Selective inhibition of Cox-2 by MK-966 caused a clinically insignificant and transient retention of sodium, but no depression of GFR. Inhibition of both Cox isoforms by indomethacin caused transient sodium retention and a decline in GFR. Our data suggest that acute sodium retention by nonsteroidal anti-inflammatory drugs in healthy elderly subjects is mediated by the inhibition of Cox-2, whereas depression of GFR is due to inhibition of Cox-1.

The purified human placental alpha 2 beta 2 heterotetrameric insulin receptor complex was reduced and dissociated into functional alpha beta heterodimers by a combination of alkaline pH and dithiothreitol treatment. Insulin treatment of the isolated alpha beta heterodimeric complex was observed to induce the complete reassociation to an alpha 2 beta 2 heterotetrameric state when analyzed by nondenaturing Bio-Gel A-1.5m gel filtration chromatography. Nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis of 125I-insulin affinity cross-linked and 32P-autophosphorylated alpha beta heterodimers demonstrated that the insulin-dependent reassociation to the alpha 2 beta 2 heterotetrameric state occurred both covalently and noncovalently under these conditions. Comparison by reducing and nonreducing sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the insulin-dependent covalent reassociation to an alpha 2 beta 2 heterotetrameric complex was due to the formation of a disulfide linkage(s) between the alpha beta heterodimers. beta subunit autophosphorylation of the control alpha 2 beta 2 heterotetrameric insulin receptor preparation was maximally stimulated within 5 min of insulin preincubation and occurred exclusively in the Mr = 400,000 alpha 2 beta 2 complex. Similarly, maximal insulin-stimulated beta subunit autophosphorylation of the alpha beta heterodimeric preparation occurred within 5 min of insulin pretreatment in the Mr = 210,000 alpha beta complex. However, 4 h of insulin pretreatment of the alpha beta heterodimer preparation induced the formation (6-fold) of a covalent 32P-labeled alpha 2 beta 2 heterotetrameric complex. Maximal stimulation of substrate phosphorylation for the alpha 2 beta 2 heterotetrameric complex was also observed to occur within 5 min of insulin treatment, whereas maximal insulin-stimulated substrate phosphorylation of the alpha beta heterodimeric complex required greater than 4 h. These data demonstrate that (i) insulin treatment can induce the reassociation of the alpha beta heterodimeric complex into a covalent alpha 2 beta 2 heterotetrameric state, and (ii) insulin-dependent protein kinase activation of the alpha beta heterodimeric insulin receptor correlates with the covalent reassociation into a disulfide-linked alpha 2 beta 2 heterotetrameric complex.

A case-control study was conducted to examine the association of beta-haemolytic non-group A streptococci and pharyngitis in a paediatric population (n=502). No association could be found between disease and traditional Lancefield groups B, C, F, or G. When the analysis included the clustering of genetically related subgroups from different Lancefield groups, an association was evident for moderate and heavy quantitations of beta-haemolytic “large colony” group C and G streptococci (Streptococcus equisimilis and human biotypes of large colony group G streptococci) (p=0.021). This study further defines a subset of the beta-haemolytic non-group A streptococci that merit recognition by both the laboratory and physician.

A study of 12 streams draining forested and non-forested catchments was made in an area of central Scotland where slow-weathering bedrock was predominantly quartzite, schists and slates. Sitka spruce (Picea sitchensis Carriere) was the most common tree species. Precipitation in the area had an annual mean pH in the range 4.3–4.5. Streams within the planted zone were always more acid than those outside and had higher concentrations of aluminium and manganese. With one exception, trout were absent from streams within long-established forests and planted salmon eggs (Salmo salar L.) died within a few weeks. A high proportion of such eggs survived in streams outside the forest. Siphlonurus lacustris Eaton was the only mayfly nymph found in the most acid streams in summer collections. In winter samples, mayfly nymphs, Heptagenia lateralis (Curtis) were found in only one forest stream but several species were present in the non-forested catchments. It is suggested that spruce forests can effectively collect acid pollutants which are subsequently washed out, thus accelerating the acidification of the soil. Streams therefore become increasingly acid as the neutralisation capacities of their catchments decrease.

Insulin and Mn/MgATP treatment of immunoaffinity-purified αβ heterodimeric insulin receptors induced the formation of an α2β2heterotetrameric insulin receptor complex. In contrast, insulin-like growth factor-1 (IGF-1) treatment was completely ineffective in inducing the association of αβ heterodimeric insulin receptors. Similarly, IGF-1 or Mn/MgATP, but not insulin, treatment of immunoaffinity-purified αβ heterodimeric IGF-1 receptors induced the formation of an α2β2heterotetrameric IGF-1 receptor complex. A monoclonal antibody specific for the insulin receptor (MA5) completely immunoprecipitated all the insulin binding activity from both the α2β2heterotetrameric and αβ heterodimeric insulin receptor complexes but did not immunoprecipitate IGF-1 receptors. Conversely, the IGF-1 receptor-specific monoclonal antibody (αIR-3) immunoprecipitated all the IGF-1 binding activity, but not insulin receptors.

A positive association between the use of artificial sweeteners, particularly saccharin, and risk of bladder cancer in males has been observed in a case-control study of 480 men and 152 women in three Provinces in Canada. The risk ratio for ever versus never used is 1·6 for males (p=0·009, onetailed test), and a significant dose-response relationship was obtained for both duration and frequency of use. The population attributable risk for males is estimated at 7%, though for diabetics, who have a similar risk ratio for artificial sweetener use as non-diabetics, the attributable risk is 33%.

Two possible methods for monitoring exposure to 2,4-difluoroaniline and 4-fluoroaniline have been investigated: measurement of methaemoglobin content in blood and measurement of urinary metabolites. Experiments using rats dosed by the oral route as a model system show that measurement of methaemoglobin content provides a very rapid and simple monitoring method, but is not very sensitive. Measurement of the ortho-hydroxy metabolites of the two compounds, as their benzoxazole derivatives, provides a much more sensitive, but complicated technique. Details of both methods are presented.