Serum and intratumoural GH and IGF-I concentrations: Prognostic factors in the outcome of canine mammary cancer

The biological implication of the growth hormone/insulin like growth factor-I (GH/IGF-I) axis in canine mammary tumours (CMT) has been recently demonstrated, however its clinical and prognostic implications are unknown. Our aim was to investigate its prognostic significance.Hormonal determinations were done by enzyme immunoassays techniques validated for canine species in serum and tumour tissue from 32 bitches with CMT and in serum and normal mammary tissue from 10 controls. Serum and tissular GH and IGF-I concentrations were significantly higher in the case of malignant tumour compared with benign and controls. GH and IGF-I elevated concentrations were significantly associated with tumour relapse and/or metastases during follow-up and in dogs with reduced survival times; however these parameters were not independent prognostic factors in multivariate analysis. This association demonstrates a link between high serum and intratumoural GH and IGF-I concentrations and a worse prognosis and opens the possibility to new anticancer endocrine therapies in dogs.     

Separating the effects of habitat amount and fragmentation on invertebrate abundance using a multi-scale framework

Context

Herbicide treatments in viticulture can generate highly contrasting mosaics of vegetated and bare vineyards, of which vegetated fields often provide better conditions for biodiversity. In southern Switzerland, where herbicides are applied at large scales, vegetated vineyards are limited in extent and isolated from one another, potentially limiting the distribution and dispersal ability of organisms.

Objectives

We tested the separate and interactive effects of habitat amount and fragmentation on invertebrate abundance using a multi-scale framework, along with additional environmental factors. We identified which variables at which scales were most important in predicting patterns of invertebrate abundance.

Methods

We used a factorial design to sample across a gradient of habitat amount (area of vegetated vineyards, measured as percentage of landscape PLAND) and fragmentation (number of vegetated patches, measured as patch density PD). Using 10 different spatial scales, we identified the factors and scales that most strongly predicted invertebrate abundance and tested potential interactions between habitat amount and fragmentation.

Results

Habitat amount (PLAND index) was most important in predicting invertebrate numbers at a field scale (50 m radius). In contrast, we found a negative effect of fragmentation (PD) at a broad scale of 450 m radius, but no interactive effect between the two.

Conclusions

The spatial scales at which habitat amount and fragmentation affect invertebrates differ, underpinning the importance of spatially explicit study designs in disentangling the effects between habitat amount and configuration. We showed that the amount of vegetated vineyards has more influence on invertebrate abundance, but that fragmentation also contributed substantially. This suggests that efforts for augmenting the area of vegetated vineyards is more beneficial for invertebrate numbers than attempts to connect them.

     

Gut sugar analysis in field-caught parasitoids: Adapting methods originally developed for biting flies

The ability to determine the presence and identity of sugars in the guts of adult parasitoids in the field would aid researchers in addressing long-standing problems in parasitoid ecology. Until very recently, however, gut sugar analyses have not been carried out on parasitoids. This is despite the development and use of methodologies for gut sugar analyses in biting flies (mosquitoes, sand-flies, black-flies, horse- and deer-flies, and biting midges) for decades. Methods used have been the cold anthrone test for the detection of gut sugars, and various forms of chromatography for the identification of gut sugars. We review the use of these methods in biting fly research and then describe the nascent field of gut sugar analyses in parasitoids. Both cold anthrone and chromatography tests have begun to be used on field-caught parasitoids, and we describe progress from our own work. We used cold anthrone on the aphid parasitoid Aphelinus albipodus (Hymenoptera: Aphelinidae), and results from one field study show that approximately one-fifth of individuals tested were positive for gut sugars. The characteristics of the field site point to the primary source of these gut sugars as being aphid honeydew. We also analysed the gut contents of Diadegma insulare (Hymenoptera: Ichneumonidae), a parasitoid of diamondback moth. In this case, HPLC analyses showed that over 85% of field-captured individuals had fed upon sugars. These same analyses suggested that honeydew may have been a major source of the gut sugars in this case also, but the sugar profiles suggest some nectar feeding. Understanding the importance of various sugar sources on parasitoid activity and effectiveness will facilitate the incorporation of sugar sources in habitat manipulation programmes as a part of IPM.     

Total chemically available (free and intrachain) lysine and furosine in pea, bean, and lentil sprouts

The effect of the germination of peas, beans, and lentils under differing conditions of illumination for different times on parameters linked to the Maillard reaction (chemically available free and intrachain lysine, lysine availability, and furosine) was evaluated. The chemically available free lysine content in the raw seeds of the three legumes was quite small compared to the chemically available intrachain lysine content, and furosine was detectable only in the beans and the lentils. The effect of germination was to increase lysine availability compared with levels in the raw seeds in all of the germinated samples, the smallest increase taking place in the lentils. In addition, furosine became detectable in all of the germinated samples. Quantities varied depending on the germination conditions but in all cases were higher than the quantities observed in the raw seeds. Linear correlations were observed to exist between some of the parameters considered in the three legumes tested.     

Middle Paleolithic assemblages from the Indian subcontinent before and after the Toba super-eruption

The Youngest Toba Tuff (YTT) eruption, which occurred in Indonesia 74,000 years ago, is one of Earth's largest known volcanic events. The effect of the YTT eruption on existing populations of humans, and accordingly on the course of human evolution, is debated. Here we associate the YTT with archaeological assemblages at Jwalapuram, in the Jurreru River valley of southern India. Broad continuity of Middle Paleolithic technology across the YTT event suggests that hominins persisted regionally across this major eruptive event.