Correction of vitamin D deficiency in a cohort of newborn infants using daily 200 IU vitamin D supplementation.

INTRODUCTION: Although the role of vitamin D in the prevention of rickets has long been well established, controversies still exist on the ideal dose of vitamin D supplementation in infants. OBJECTIVE: We assessed serum 25-hydroxyvitamin D (25OHD) status simultaneously in maternal and cord samples and the response to vitamin D3 supplementation in neonates. METHODS: Serum 25OHD levels were evaluated from maternal, and umbilical cord samples from term normal pregnancies. Repeat 25OHD levels were assessed in neonates with 25OHD below 30 nmol/L following vitamin D3 200 IU daily after 6 weeks. RESULTS: Blood samples were taken including 57 cord samples and 16 follow-up neonatal samples. Maternal and cord serum 25OHD were 43 ± 21 and 29 ± 15 nmol/L, respectively. Infants with 25OHD < 30 nmol/L (19.8 ± 4.7 nmol/L) had a significant increase in serum 25OHD (63.3 ± 14.5 nmol/L) following vitamin D3 200 IU daily after 6 weeks. CONCLUSION: Healthy Irish infants born at term are at high risk of vitamin D deficiency, but vitamin D3 200 IU daily, rapidly corrects poor vitamin D status.

Maternal and infant nutritional supplementation practices in Ireland: implications for clinicians and policymakers.

This prospective Irish observational study examined maternal and infant nutritional supplement use. From an initial sample of 539 mothers recruited from the Coombe Women and Infants University Hospital in Dublin (during 2004-2006), 450 eligible mothers were followed up at 6 weeks and 6 months postpartum. Only 200 women (44.4%) complied with peri-conceptional folic acid at the recommended time with strong social patterning associated with its uptake. Almost 10% of the sample (n = 44) consumed a combined multivitamin and mineral supplement during pregnancy. A vitamin D-containing supplement was provided to only 5 (1.1%) and 15 (3.3%) infants at 6 weeks and 6 months, respectively. A national guideline that advises on adequate and safe use of both vitamin and multivitamin supplements during pregnancy with particular reference to vitamin A and D is warranted. Given the re-emergence of rickets in Ireland, and the reported morbidities associated with vitamin D insufficiency, promoting and monitoring compliance with 200 IU [5 microg] daily vitamin D supplements to all infants particularly those from higher risk groups from birth to 1 year, should be a public health priority.

Permanent and functional male-to-female sex reversal in d-rR strain medaka (Oryzias latipes) following egg microinjection of o,p'-DDT.

Complete sex reversal of fish is accomplished routinely in aquaculture practices by exposing fish to exogenous sex steroids during gonadal differentiation. A variety of environmental chemicals are also active at sex steroid receptors and theoretically possess the potential to alter normal sexual differentiation in fish. However, in controlled environmental chemical exposures to date, only partial alterations of fish sexual phenotype have been observed. Here we report complete, permanent, and functional male-to-female sex reversal in the Japanese medaka (Oryzias latipes, d-rR strain) after a onetime embryonic exposure to the xenoestrogen o, p'-DDT. d-rR strain medaka are strict gonochorists that possesses both sex-linked pigmentation, which distinguishes genotypic sex, and sexually dimorphic external secondary sexual characteristics, which distinguish phenotypic sex. We directly microinjected the xenoestrogen o, p'-DDT into the egg yolks of medaka at fertilization to parallel the maternal transfer of lipophilic contaminants to the embryo. At 10 weeks of age, microinjected medaka were examined for mortality and sex reversal. A calculated embryonic dose of 511 +/- 22 ng/egg o, p'-DDT (mean +/- standard error) resulted in 50% mortality. An embryonic exposure of 227 +/- 22 ng/egg o, p'-DDT resulted in 86% (6 of 7) sex reversal of genetic males to a female phenotype (XY females). XY females were distinguished by sex-linked male pigmentation accompanying female secondary sexual characteristics. Histologic examination of the gonads confirmed active ovaries in 100% of the XY females. In 10-day breeding trials in which XY females were paired with normal XY males, 50% of the XY females produced fertilized embryos; this represents a comparable breeding success rate to normal XX females. Fertilized eggs produced from XY females hatched to viable larvae. These results clearly indicate that a weakly estrogenic pesticide, o, p'-DDT, when presented during the critical period of gonadal development, can profoundly alter sexual differentiation.

Autobiographical amnesia resulting from bilateral paramedian thalamic infarction. A case study in cognitive neurobiology.

A patient with a chronic amnesic state resulting from bilateral paramedian thalamic infarction showed a pattern of retrograde amnesia not previously reported. Personally relevant autobiographical memory was profoundly impaired, whereas knowledge of famous people and public events was relatively spared. Furthermore, knowledge of famous people, including the ability to make accurate temporal judgements, was less affected than knowledge of public events. In addition, we have documented a severe and systematic distortion of personal memory. These findings are not compatible with current accounts of retrograde amnesia based either upon the type of information stored (e.g. episodic versus semantic memory), or upon simple storage versus access models. We propose an explanation based upon an interactive cognitive model in which the patient shows a disorder at the 'thematic retrieval framework' level of memory organization due to a disconnection of frontal and medial temporal memory systems.