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Aim: Understanding the role of enemy release in biological invasions requires an assessment of the invader's home range, the number of invasion events and enemy prevalence. The common wasp (Vespula vulgaris) is a widespread invader. We sought to determine the Eurasian origin of this wasp and examined world-wide populations for microsporidian pathogen infections to investigate enemy release. Location: Argentina, Eurasia, New Zealand. Methods: A haplotype network and phylogenetic tree were constructed from combined wasp COI and cytb mitochondrial markers. A morphometric study using canonical discriminant analysis was conducted on wing venation patterns. Microsporidian pathogens prevalence was also examined using small subunit rRNA microsporidia-specific primers. Results: Our spatially structured haplotype network from the native range suggested a longitudinal cline of wasp haplotypes along an east to west gradient. Six haplotypes were detected from New Zealand, and two from Argentina. The populations from the introduced range were genetically similar to the western European, United Kingdom and Ireland. The morphometric analysis showed significant morphological variation between countries and supported the Western European origin for New Zealand populations, although not for Argentine samples. Microsporidian infection rates were highest in New Zealand samples (54%), but no significant differences in infection rates were observed between the invaded and native range. Nosema species included matches to N. apis (a pathogen from honey bees) and N. bombi (from bumble bees). Main conclusions: Multiple introductions of the common wasp have occurred in the invaded range. A high microsporidian infection rate within the native range, combined with multiple introductions and a reservoir of pathogens in other social insects such as bees, likely contributes to the high microsporidian infection rates in the invaded range. Enemy release is likely to be more frequent when pathogens are rare in the home range, or are host specific and rare in reservoir populations of the introduced range. Fil: Lester, P. J.. Victoria University of Wellington; Nueva Zelanda Fil: Gruber, M. A. M.. Victoria University of Wellington; Nueva Zelanda Fil: Brenton Rule, E. C.. Victoria University of Wellington; Nueva Zelanda Fil: Archer, M.. York St. John University; Reino Unido Fil: Corley, Juan Carlos. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Dvorak, L.. Mestske muzeum Marianske Lazne; República Checa Fil: Masciocchi, Maité. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Patagonia Norte. Estación Experimental Agropecuaria San Carlos de Bariloche; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Oystaeyen, A. Van. Katholikie Universiteit Leuven; Bélgica

Epidemiologic evidence suggests that cancer incidence is associated with diabetes as well as certain diabetes risk factors and treatments. This consensus statement of experts assembled jointly by the American Diabetes Association and the American Cancer Society reviews the state of science concerning 1) the association between diabetes and cancer incidence or prognosis; 2) risk factors common to both diabetes and cancer; 3) possible biologic links between diabetes and cancer risk; and 4) whether diabetes treatments influence the risk of cancer or cancer prognosis. In addition, key unanswered questions for future research are posed.

Obesity, particularly visceral adiposity, is an established risk factor for colorectal cancer (CRC) and this is thought to result, at least in part, from insulin resistance and chronic hyperinsulinemia that may be mediated by adipokines. Serum levels of adiponectin, the most abundant protein secreted from adipocytes, are decreased in obesity and are inversely associated with insulin resistance and hyperinsulinemia. The objective of this study was to determine whether elevated circulating adiponectin plays a role in colon carcinogenesis using adiponectin transgenic (AdTg) mice that have 2–3-fold elevated circulating adiponectin but similar body weights as wildtype (WT) littermates used as controls. Eight-week old male and female AdTg and WT mice were treated with 4 weekly injections of the colon-specific carcinogen azoxymethane (AOM). One week following the last dose of AOM, all mice were placed on a high-fat diet and killed 24 weeks later, at 36 weeks of age, for the analysis of colon tumors. Glucose tolerance tests (GTT) were performed by injecting 2g/kg dextrose or 1.25–1.5 g/kg dextrose into all 12-week and 32–35-week-old mice respectively, and measuring blood from the tail vein 15, 30, 60 and 120 min following glucose administration. There were no significant differences in colon tumor incidence, number or size between AdTg and WT mice of either sex. AdTg mice of both sexes displayed resistance to diet-induced decreases in insulin sensitivity. Our results show that constitutively elevated levels of circulating adiponectin in AdTg mice do not confer protection against the development of colon tumors. © 2008 Wiley-Liss, Inc.

SYNOPSIS An account is given of worker characteristics, worker activities and brood characteristics in nests of Vespula vulgaris. Variations in queen productivity and efficiency of reproduction are discussed.

Obesity is associated with impaired fatty acid (FA) oxidation and increased de novo hepatic lipogenesis that may contribute to the development of hypertriglyceridemia, an important risk factor for the development of cardiovascular disease. Strategies to improve hepatocyte FA metabolism, including dietary interventions, are therefore important for the prevention of obesity-associated co-morbidities. Farnesol is consumed in the diet as a component of plant products. In the present study, we administered farnesol orally to rats for seven days and found significantly reduced serum triglyceride concentrations compared with controls. Potential mechanisms underlying the hypotriglyceridemic effect of farnesol were investigated using clone-9 cultured rat hepatocytes. Farnesol significantly upregulated expression of peroxisome proliferator-activated receptor alpha (PPARalpha) and the PPARalpha-regulated genes fatty acyl-CoA oxidase and carnitine palmitoyl transferase 1a, suggesting that increased hepatic FA oxidation may contribute to serum triglyceride lowering in rats. Farnesol did not change SREBP-1c mRNA levels, but significantly down-regulated fatty acid synthase (FAS) mRNA and protein levels and activity, indicating that attenuated lipogenesis may also contribute to hypotriglyceridemic effects of farnesol in vivo. Rescue experiments revealed that down-regulation of FAS by farnesol was not related to activation of PPARalpha, but rather was caused by a 9-cis retinoic acid mediated mechanism that involved down-regulation of retinoid X receptor beta. Diets rich in plant products are associated with a lower risk of cardiovascular disease. Our findings suggest that farnesol may contribute to this protective effect by lowering serum TG levels.

To report a technique for eye enucleation in standing sedated horses and to report outcome in 40 horses.Retrospective study.Horses (n=40) requiring eye enucleation.The eye was enucleated using a transpalpebral technique in 40 horses restrained in stocks and sedated. Anesthesia of orbital structures was provided by local nerve blocks and infiltration of the surgical site with local anesthetic solution.Affected eyes were successfully enucleated with the horse standing. Short-term complications included moderate swelling (5 horses) and wound discharge (1). Long-term complications were not observed.A diseased eye can be safely enucleated with a horse standing.Enucleating an equine eye in the standing position eliminates the risks and costs of general anesthesia.

Circulating insulin-like growth factor I (IGF-I) is associated with increased risk of colorectal cancer. It is not clear, however, whether IGF-1 plays a direct causative role in colon carcinogenesis or whether it mediates the known promoting effects of insulin. The objective of this study was to determine the role of IGF-1 in colon carcinogenesis using liver-specific IGF-I deficient (LID) mice that exhibit 70% reductions in circulating IGF-I. Female and male LID mice were treated with the colon-specific carcinogen azoxymethane to induce aberrant crypt foci (ACF) or colon tumors. Female LID mice developed significantly fewer ACF and had normal insulin levels compared to controls. Male LID mice, however, were hyperinsulinemic and exhibited no significant differences in ACF development compared to controls. In the tumor study, both male and female LID mice were hyperinsulinemic and had no significant differences in tumor incidence or multiplicity compared to their respective controls. There was a significant 25% reduction in tumor size, however, in both male and female LID mice compared to controls. These data suggest that IGF-I deficiency attenuates the promoting effect of insulin on colon carcinogenesis and that IGF-I is an independent promoter of the growth of established tumors. Our findings implicate both IGF-I and insulin as important promoters of colon cancer development.

The genus Dolichovespula consists provisionally of 18 species. Aerial nest site characteristics have been established for seven species but most of these species show flexibility in their choice of nest sites and two species often nest in shallow subterranean situations. Colony length is usually just over 3 months to approximately 4 months, but at lower latitudes may extend to more than 5 months. Mature colony size is usually approximately 1000 cells with more large cells than small cells. Parasitized colonies have a shorter colony cycle and smaller colonies. During the production of the sexual brood the larva/worker ratio reaches its lowest value of approximately 2.5 larvae per worker. Colonies often have upper mixed combs of small and large cells. Total adult production is usually less than 2000 adults. Colonies of D. arenaria and D. norwegica may specialize in mainly producing males or queens. Variations in mature colony size and production of queens is probably a consequence of the number of workers present, particularly early in the colony cycle.

Mutual policing is an important mechanism for maintaining social harmony in group-living organisms. In some ants, bees, and wasps, workers police male eggs laid by other workers in order to maintain the reproductive primacy of the queen. Kin selection theory predicts that multiple mating by the queen is one factor that can selectively favor worker policing. This is because when the queen is mated to multiple males, workers are more closely related to queen's sons than to the sons of other workers. Here we provide an additional test of worker policing theory in Vespinae wasps. We show that the yellowjacket Vespula rufa is characterized by low mating frequency, and that a significant percentage of the males are workers' sons. This supports theoretical predictions for paternities below 2, and contrasts with other Vespula species, in which paternities are higher and few or no adult males are worker produced, probably due to worker policing, which has been shown in one species, Vespula vulgaris. Behavioral observations support the hypothesis that V. rufa has much reduced worker policing compared to other Vespula. In addition, a significant proportion of worker-laid eggs were policed by the queen. ispartof: Evolution vol:59 issue:6 pages:1306-14 ispartof: location:United States status: published

A role for mevalonate in cancer development has long been suggested by findings that 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase activity is elevated in malignant cells. Increased synthesis of mevalonate and mevalonate-derived nonsterol isoprenoids supports increased cell proliferation through the activation of growth-regulatory proteins and oncoproteins, and by promoting DNA synthesis. We have recently shown that mevalonate promotes the growth of human breast cancer cells both in culture and as tumors grown in nude mice. Inhibiting mevalonate synthesis, therefore, may be an effective strategy to impair the growth of malignant breast cells. Several dietary compounds with known anti-cancer effects are also reported to inhibit HMG-CoA reductase activity. Here, we review evidence suggesting that inhibition of mevalonate synthesis may mediate the protective effects of cholesterol, plant isoprenoids, genistein, and long-chain n-3 polyunsaturated fatty acids (PUFAs) on experimental breast cancer.

CLA inhibits mammary cancer and reduces body fat accumulation in rodents. It is not known whether uncoupling proteins (UCP), which are modulators of energy balance and metabolism, play a role in these actions of CLA. To determine the effects of dietary CLA on the expression of UCP in various tissues, 5-wk-old Sprague-Dawley rats and C57Bl/6 mice were fed diets containing 1% CLA for 3 wk. CLA treatment reduced adipose depot weights in both rats and mice but had no significant effects on body weight. There was a species-specific effect of CLA on the expression of UCP. Whereas CLA did not affect the expression of UCP in most tissues in rats, mice fed CLA had increased expression of UCP2 in the mammary gland, brown adipose tissue (BAT), and white adipose tissue (WAT). Furthermore, UCP1 and UCP3 mRNA and protein levels in BAT were significantly lower in CLA-fed mice compared to controls. Skeletal muscle UCP3 mRNA was unchanged, but UCP3 protein levels were significantly increased in mice, suggesting translational or posttranslational regulation of this protein. Results from this study suggest that alterations in the expression of UCP in mice may be related to the previously reported effects of dietary CLA in lowering adiposity and increasing FA oxidation. In rats, however, induction of UCP is not likely to be responsible for fat reduction or for the inhibitory action of CLA on mammary carcinogenesis.

Summary 1. Thirteen time series, varying from 17 to 27 years, of the abundance of Vespula germanica and V. vulgaris from lowland England are examined. The time series depend on either spring queens and workers taken in Malaise or suction traps, or collected colonies. 2. During the late 1970s and early 1980s, the abundance of V. germanica declined abruptly but that of V. vulgaris did not. 3. During the early 1980s, the 2-year cycle of annual abundance of V. vulgaris changed to a nearly perfectly damped pattern of annual abundances. 4. The most likely factor causing these population changes was the increased use of pesticides acting directly by killing the wasps and indirectly by reducing their food resources. 5. The difference in response of the two species to increased pesticide use may be related to a difference in foraging ability.

The insulin-like growth factors (IGFs) are mitogenic polypeptides that have been linked to a variety of normal physiological processes as well as neoplasia. Overexpression of several components of the IGF system is associated with hepatocarcinogenesis in humans and rodents. In rat liver, diets rich in n-6 polyunsaturated fatty acid (PUFA) enhance the development of preneoplastic lesions and tumors. Therefore, the objective of this study was to determine the effect of these dietary fatty acids on the hepatic expression of the various components of the IGF system. The mRNA levels of IGF-1 and the type 1 receptor were not different in livers of rats fed a diet containing 20% corn oil (CO) compared with those fed 5% CO. Analysis of the IGF binding proteins revealed that insulin-like growth factor binding protein-1 (IGFBP-1) levels were altered by the amount and type of dietary fat. A 2.5-fold induction of IGFBP-1 mRNA occurred within 1 week after the animals were fed the 20% corn oil diet compared with those fed 5% CO and was further enhanced to over 6-fold after 1 month. Furthermore, IGFBP-1 protein was only detectable in the livers of animals fed the 20% CO diet. Induction of IGFBP-1 mRNA (4.5-fold) also occurred in rats fed a high-fat diet containing safflower (rich in n-6 PUFAs) compared with those fed a high-fat diet containing menhaden oil (rich in n-3 PUFAs). The induction of IGFBP-1 mRNA was independent of serum insulin levels and the development of insulin resistance. Since IGFBP-1 mRNA is upregulated in regenerating liver, we reasoned that the induction of IGFBP-1 mRNA may be associated with an increase in cell proliferation; however, no difference was observed in the hepatic labeling index of rats fed the 20% CO compared with the 5% CO diet. In summary, these studies show a striking induction by dietary n-6 PUFAs of hepatic IGFBP-1, a protein that has been implicated in liver cancer development.

3-Hydroxy-3-methylglutaryl (HMG)-CoA reductase, the rate-limiting enzyme in cholesterol biosynthesis, catalyzes the formation of mevalonate which is also required for cell proliferation. Changes in HMG-CoA reductase may mediate the differential effects of n-3 and n-6 polyunsaturated fatty acids (PUFA) on experimental mammary tumorigenesis, but the mechanisms by which these fatty acids regulate HMG-CoA reductase are unclear. To determine whether the low density lipoprotein receptor (LDL-R) is required for this regulation, groups of female LDL-R knockout (-/-) and wild-type (+/+) mice were fed 7% fat diets rich in either n-3 (menhaden oil) or n-6 (safflower oil) PUFA for 1 wk. Dietary PUFA and deletion of the LDL-R had independent effects on HMG-CoA reductase and serum lipids, and a significant diet-gene interaction was observed. The effects of PUFA on HMG-CoA reductase in the mammary gland, but not the liver, were mediated by the LDL-R. We also observed that differences in HMG-CoA reductase and serum LDL-cholesterol, high density lipoprotein cholesterol, and triglycerides between -/- and +/+ mice were dependent on whether the mice were fed n-3 or n-6 PUFA. Differences between -/- and +/+ mice were much greater when animals were fed n-6 PUFA rather than n-3 PUFA. These results show that the LDL-R mediates the effects of PUFA on HMG-CoA reductase in the mammary gland but not the liver. Furthermore, the composition of dietary PUFA profoundly influences the effects of deleting the LDL-R on HMG-CoA reductase and serum lipids and suggests that diet may influence the phenotype of other knock-out or transgenic animals.

The occurrence of Ha-ras and Ki-ras oncogenes was investigated in mammary tumors produced by treating genetically resistant Copenhagen (Cop) rats with N-methyl-N-nitrosourea. G35-->A codon 12 mutations in both Ha-ras and Ki-ras genes were analyzed by a polymerase chain reaction/liquid hybridization and gel retardation assay. More than half of the adenocarcinomas analyzed contained an activated Ha-ras gene. This was also the predominant mutation in similar tumors from susceptible Buf/N rats, suggesting a common mechanism of initiation. In contrast, only two of 15 mammary adenosquamous carcinomas from the Cop rats contained an activated Ha-ras gene, suggesting a different initiation mechanism for most of these tumors. Ki-ras activation was found in none of five and one of five adenocarcinomas from Buf/N and Cop rats, respectively, and in none of 13 adenosquamous carcinomas from Cop rats. These results suggest that Ki-ras activation does not play a major role in the initiation of the mammary tumors.

alpha-Acetoxy-N-nitrosodimethylamine, an activated derivative of the carcinogen N-nitrosodimethylamine, methylated in vitro a plasmid containing the human c-Ha-ras-1 proto-oncogene, resulting in the generation of a transforming oncogene, assayed by transfection into NIH 3T3 cells. The resulting transformed cells were tumorigenic and metastatic in immune-deprived mice. Further transfection using tumor DNA led to the formation of three secondary NIH 3T3 transformants. DNA from these secondary transformants contained human ras gene sequences. Two of the three secondary transformants contained G----A mutations at guanine 35 in codon 12, and the third secondary transformant retained the wild-type sequence at codons 12, and 61. For the latter, the activating mutation was not determined. These results demonstrate that a simple methylating agent can activate a normal human ras proto-oncogene to a transforming oncogene.

1 Six categories of immature and five categories of mature colonies are described and their developmental relationships suggested. 2 Mature brood destroyed by the workers became numerous in 46.4% of the immature colonies. Most of these formed unsuccessful colonies (36.9%) producing few or no queens. The remaining 9.5% recovered to form successful colonies. 3 Successful colonies either reared queens only (mean 356 queens), or queens (mean 1461) and males (mean 254) in their large cells. 4 The number of small cells in mature colonies correlated with the number of cells built by the founder queen. 5 The greater the number of large cells in a mature colony the greater were the chances that a larger proportion of these cells would be used to rear adults. 6 The number of small and large cells are correlated in mature successful colonies. 7 Queen activity and quality are important factors in the control of colony size and success. 8 Selective destruction of male sealed brood in the large cells is linked to worker, rather than queen, control.

The solubilization of fish protein concentrate (FPC) by Bacillus subtilis protease (Monzyme) has been investigated. Conditions have been defined which eliminate the problems of microbial contamination and salt accumulation. A Kinetic treatment revealed that enzyme is adsorbed to the surface of the substrate, exposed to aqueous phase. The overall kinetics were described by a sequence of two first-order processes—an initial, fast reaction in which loosely bound polypeptide chains are cleaved from an insoluble protein particle, and a second, slower reaction in which more compacted core protein is digested.

Summary 1. Populations of introduced species are often thought to perform differently, or experience different population dynamics, in their introduced range compared to their native habitat. Differences between habitats in climate, competition or natural enemies may result in populations with varying density dependence and population dynamics. 2. We examined the long‐term population dynamics of the invasive common wasp, Vespula vulgaris, in its native range in England and its invaded range in New Zealand. We used 39 years of wasp density data from four sites in England, and 23 years of data from six sites in New Zealand. Wasp population time series was examined using partial rate correlation functions. Gompertz population models and multivariate autoregressive state‐space (MARSS) models were fitted, incorporating climatic variation. 3. Gompertz models successfully explained 59–66% of the variation in wasp abundance between years. Density dependence in wasp populations appeared to act similarly in both the native and invaded range, with wasp abundance in the previous year as the most important variable in predicting intrinsic rate of increase (r). No evidence of cyclic population dynamics was observed. 4. Both the Gompertz and MARSS models highlighted the role of weather conditions in each country as significant predictors of annual wasp abundance. The temporal evolution of wasp populations at all sites was best modelled jointly using a single latent dynamic factor for local trends, with the inclusion of a latent spring weather covariate. That same parsimonious multivariate model structure was optimal in both the native and invaded range. 5. Density dependence is overwhelmingly important in predicting wasp densities and ‘wasp years’ in both the native and invaded range. Spring weather conditions in both countries have a major influence, probably through their impact on wasp colony initiation and early development. The population dynamics in the native range and invaded range show no evidence of cyclic boom‐and‐bust dynamics. Invasive species may not exhibit different population dynamics despite considerable variation in abundances throughout their distribution.