Sea urchin maternal and embryonic U1 RNAs are spatially segregated in early embryos.

We have used in situ hybridization and cell fractionation methods to follow the distribution of U1 RNA and immunofluorescence microscopy to follow the distribution of snRNP proteins in oocytes, eggs, and embryos of several sea urchin species. U1 RNA and U1-specific snRNP antigens are concentrated in germinal vesicles of oocytes. Both appear to relocate after oocyte maturation because they are found primarily, if not exclusively, in the cytoplasm of mature unfertilized eggs. This cytoplasmic residence is maintained during early cleavage and U1 RNA is first detectable in nuclei of micromeres at the 16-cell stage. Between morula and gastrula stages the steady-state concentrations of both RNA and antigens gradually increase in nuclei and decrease in cytoplasm. Surprisingly, analysis of the distribution of newly synthesized U1 RNA shows that it does not equilibrate with the maternal pool. Instead new transcripts are confined to nuclei, while cytoplasmic U1 RNAs are of maternal origin. This lack of equilibration and the conversion of maternal U1 RNAs from nuclear species in oocytes to cytoplasmic in embryos suggests that these RNPs (or RNAs) are structurally altered when released to the cytoplasm at oocyte maturation.

Insulin adjustment by a diabetes nurse educator improves glucose control in insulin-requiring diabetic patients: a randomized trial.

BACKGROUND: Diabetic patients taking insulin often have suboptimal glucose control, and standard methods of health care delivery are ineffective in improving such control. This study was undertaken to determine if insulin adjustment according to advice provided by telephone by a diabetes nurse educator could lead to better glucose control, as indicated by level of glycated hemoglobin (HbA1c). METHODS: The authors conducted a prospective randomized trial involving 46 insulin-requiring diabetic patients who had poor glucose control (HbA1c of 0.085 or more). Eligible patients were those already taking insulin and receiving endocrinologist-directed care through a diabetes centre and whose most recent HbA1c level was 0.085 or higher. The patients were randomly assigned to receive standard care or to have regular telephone contact with a diabetes nurse educator for advice about adjustment of insulin therapy. RESULTS: At baseline there was no statistically significant difference between the 2 groups in terms of HbA1c level (mean [and standard deviation] for standard-care group 0.094 [0.008] and for intervention group 0.096 [0.010]), age, sex, type or duration of diabetes, duration of insulin therapy or complications. After 6 months, the mean HbA1c level in the standard-care group was 0.089 (0.010), which was not significantly different from the mean level at baseline. However, the mean HbA1c level in the intervention group had fallen to 0.078 (0.008), which was significantly lower than both the level at baseline for that group (p < 0.001) and the level for the standard-care group at 6 months (p < 0.01). INTERPRETATION: Insulin adjustment according to advice from a diabetes nurse educator is an effective method of improving glucose control in insulin-requiring diabetic patients.