Subtle temperature increase can interact with individual size and social context in shaping phenotypic traits of a coldwater fish.

Temperature and individual egg size have been long studied in the development of fishes because of their direct effects on individual fitness. Here we studied the combined effects of three important factors for fish development, i.e. egg size, social environment and water temperature. Arctic charr (Salvelinus alpinus), a coldwater fish known to be phenotypically plastic, was used to investigate how these factors may affect growth and foraging behaviour of juvenile fish in a benign environment. We accounted for the social environment during early development by comparing fish raised in groups and in isolation. We examined the effect of egg size and a 2 °C difference on foraging behaviour, activity and growth a few weeks after first feeding. Growth trajectories of fish originating from large and small eggs were similar within each temperature: larger fish coming large eggs were at all time larger than smaller fish. There was no indication that small fish raised at a higher temperature grew faster than larger fish raised at a lower temperature. A 2 °C difference in temperature affected the behaviour of fish differently according to body size and/or social context. The foraging probability difference between fish raised in groups and fish briefly isolated was higher at 4.5 °C than at 6.5 °C for both size fish. Finally, there was no repeatability in foraging behaviour and mobility for isolated individuals. These results highlight the importance of small changes in temperature when evaluating growth and behaviour of fishes, and reveal the importance of considering the interaction of temperature with other factors, e.g. individual size and social environment, especially at early stages of development in fishes. We discuss these findings in the context of rapid changes in temperature and how temperature and its interaction with other factors may affect the phenotypes, ecology and evolution of coldwater fishes.

Prolonged glucose requirements after intentional glargine and aspart overdose.

Intentional insulin overdose in diabetic patients is a rather rare critical situation. We report the case of a patient suffering from type 1 diabetes who was found comatose with a plasma glucose close to zero after having injected herself massive doses of both aspart and glargine insulin analogues. The prevention of hypoglycaemic episodes in this patient required a long-term glucose infusion (i.e., 59 hours) which significantly exceeds the usual time-effect profile of glargine. This observation emphasizes again that clinicians should be aware of the extremely prolonged action of long acting insulin analogue glargine after intentional massive injection in order to avoid a too early interruption of glucose infusion and a subsequent risk of relapse of severe hypoglycaemic episodes.

Lumpectomy with tamoxifen as primary treatment for elderly women with early-stage breast cancer.

BACKGROUND: Appropriate therapy for women over 70 years of age with breast cancer is currently a highly debated topic. The aim of this study was to determine whether a subset of patients could be identified in which lumpectomy alone, followed by tamoxifen, would offer adequate local, regional, and long-term control of disease. METHODS: A retrospective analysis of 171 women over the age of 70 with stage I or II breast carcinomas treated by the senior authors from 1984 to 1998 was undertaken. One hundred and thirty-five patients who received conventional treatment were compared with 43 patients who received lumpectomy alone followed by tamoxifen. Differences in patient and tumor characteristics and in disease outcome and complications between the two groups were analyzed. RESULTS: The patients treated with lumpectomy and tamoxifen were significantly older (80 versus 76 years) and had significantly smaller tumors (1.4 versus 1.8 cm) than the conventionally treated patients. No significant differences were noted in comorbidities, clinical tumor size, histology, margin status, tumor differentiation, and hormone receptor status. There were no local or regional recurrences and only 1 distant recurrence (2%) in the lumpectomy with tamoxifen patients. In the conventionally treated group, 4 patients (3%) recurred locally, none regionally, and 18 patients (13%) recurred distantly. CONCLUSION: These data indicate that lumpectomy alone followed by tamoxifen results in an acceptable disease outcome in a subset of elderly women with breast cancer. This subset is defined by older patients with small, hormone receptor positive tumors.

Drosophila Rrp1 3'-exonuclease: demonstration of DNA sequence dependence and DNA strand specificity.

Drosophila Rrp1 (recombination repair protein 1) is a DNA repair enzyme whose nuclease activities include AP-endonuclease, 3'-exonuclease, 3'-phosphodiesterase and 3'-phosphatase. This study investigates the sequence specificity of the dsDNA 3'-exonuclease activity of Rrp1. We demonstrate that the activity is more efficient in purine-rich regions of dsDNA than in pyrimidine-rich regions. Rrp1 exonuclease activity is examined at 3'-terminal homopurine or homopyrimidine tracts, at junctions between purine- and pyrimidine-rich sequences and upon encountering repeated dinucleotide runs. The data show that purine-purine and 3'-pyrimidine-5'-purine dinucleotide bonds are cleaved faster than 3'-purine-5'-pyrimidine or pyrimidine-pyrimidine bonds. Thus, the base occupying the penultimate position in the 3'-terminal dinucleotide may be important in determining the relative efficiency of bond cleavage by Rrp1. These findings may reflect upon specific DNA-protein interactions in the enzyme active site.