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This paper describes the technical information and performance of a new multi-objective chamber system enabling the control of environmental variables ( e.g., temperature, CO, air humidity, wind speed, and UV-B radiation) for understanding plant responses to climate change. Over a whole growing season, four different climate scenarios were evenly programmed into the system's 16 chambers as ambient environment (AMB), elevated temperature (ET), elevated CO concentration (EC) and elevated temperature and CO concentration (ETC). Simultaneously, the chamber effects were assessed regarding the physiological responses and growth of a boreal perennial grass (reed canary grass, Phalaris arundinacea L.). During the growing season, the chamber system provided a wide variety of climatic conditions for air temperature ( T), relative humidity (RH) and CO concentration ( C) in the AMB chambers following outside conditions. The target temperature (+3.5°C) was achieved to a good degree in the ET and ETC chambers, being on average 3.3°C and 3.7°C higher than ambient conditions, respectively. The target concentration of CO (700 ppm) was also well achieved in the EC and ETC chambers, being on average 704 ppm and 703 ppm, respectively. The stable airflow condition inside all of the chambers provided a homogeneous distribution of gases and temperature. The decreases in RH and increases in vapour pressure deficit (VPD) in the elevated temperature chambers were also maintained at a low level. Chamber effects were observed, with some physiological and growth parameters of plants being significantly lower in the AMB chambers, compared to outside conditions. The plant growth was negatively affected by the reduced radiation inside the chambers. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the prevalence of enamel defects in both primary and permanent dentitions of the same preterm children, and to elucidate the role of early dietary mineral and vitamin D intake in the etiology of the enamel defects. The status of the primary and permanent teeth was evaluated in 32 preterm children and in 64 control children. The prevalence of enamel defects in children born preterm was clearly higher as compared with controls in both the primary (78% vs 20%, P<0.001) and permanent (83% vs 36%, P<0.001) dentitions. Neither the mineral supplementation used nor a vitamin D dose of 1000 IU/day, as compared with a lower dose of 500 IU/day, reduced the prevalence of enamel defects in the primary or permanent dentitions. Further studies are needed to clarify whether achieving near optimum intra-uterine mineral retention would lower the prevalence of subsequent enamel defects in infants born prematurely. [ABSTRACT FROM AUTHOR]

A randomised double blind placebo controlled study was conducted to determine whether a one week course of dexamethasone could reduce the severity of bronchopulmonary dysplasia in preterm infants without compromising their adrenal function. Forty one infants with a mean birth weight of 880 g and a gestational age of 27 weeks who were ventilator dependent at 10 days of age were enrolled. At the age of 28 days pulmonary outcome was significantly better in the girls treated with dexamethasone but not in all infants. There was no difference between the groups in the long term outcome, except for a shorter duration of supplemental oxygen in dexamethasone treated female infants. After the one week dexamethasone treatment there was a significant but short lived suppression of the basal cortisol concentrations and the adrenal response to corticotrophin (ACTH). No serious side effects were observed. It is concluded that early one week dexamethasone treatment improves short term pulmonary outcome in premature infants, but there is no clear evidence of long term benefits. [ABSTRACT FROM AUTHOR]

A family in which the proband showed phenotypic signs of both the Turner and Down syndromes was studied cytogenetically and with restriction fragment length polymorphisms. The proband's karyotype was 46,X,+21, showing double aneuploidy without any signs of mosaicism. The single X and one chromosome 21 were of paternal origin while two chromosomes 21 were of maternal origin. The nondisjunction of chromosome 21 took place in maternal meiosis II. If it is assumed that the absence of mosaicism renders postzygotic mitotic loss of the X chromosome unlikely, then the X chromosome would have been lost in maternal meiosis I or II. Recombination had occurred between the nondisjoined chromosomes 21. We conclude that double nondisjunction took place in one parent and that asynapsis was not a prerequisite for the autosomal nondisjunction. [ABSTRACT FROM AUTHOR]

Aims: To elucidate the development of primary and permanent teeth and to interpret the effect of different calcium, phosphorus, and vitamin D supplementation in the neonatal period on dental maturation in preterm children.Methods: Preterm infants were randomised to four groups to receive a vitamin D dose of 500 or 1000 IU/day and calcium and phosphorus supplemented or unsupplemented breast milk. The maturity of the primary and permanent teeth was recorded in 30 preterm children. Sixty children aged 2 years and 60 children aged 9-11 years served as controls. Bone mineral content/density was assessed in the preterm infants.Results: The median (range) corrected teething age was 7 (2-16) months in preterm infants and 6 (2-12) months in controls (p = 0.43). The median (range) number of erupted teeth at 2 years of age was 16 (11-19) in preterm infants and 16 (12-20) in controls (p = 0.16). Maturation of the permanent teeth in the preterm infants was not delayed compared with the controls (mean Demirjian SDS 0.16 v 0.49, p = 0.14). Early dietary intake of either mineral or vitamin D did not affect maturation of the primary dentition in preterm children. Children receiving the higher vitamin D dose in the neonatal period had more mature permanent dentition than those receiving the lower dose, but mineral intake did not affect maturation of the permanent teeth. Dental maturation did not correlate with bone mineral status.Conclusions: This is the first longitudinal study to follow primary and permanent tooth maturation in the same preterm children. Premature birth has no appreciable late sequelae in tooth maturation. [ABSTRACT FROM AUTHOR]

Aims: To test the hypothesis that a vitamin D dose of 200 IU/kg, maximum 400 IU/day, given to preterm infants will maintain normal vitamin D status and will result in as high a bone mineral density as that attained with the recommended dose of 960 IU/day.Methods: Thirty nine infants of fewer than 33 weeks of gestational age were randomly allocated to receive vitamin D 200 IU/kg of body weight/day up to a maximum of 400 IU/day or 960 IU/day until 3 months old. Vitamin D metabolites, bone mineral content and density were determined by dual energy x-ray absorptiometry, and plasma ionised calcium, plasma alkaline phosphatase, and intact parahormone measurements were used to evaluate outcomes.Results: The 25 hydroxy vitamin D concentrations tended to be higher in infants receiving 960 IU/day, but the differences did not reach significance at any age. There was no difference between the infants receiving low or high vitamin D dose in bone mineral content nor in bone mineral density at 3 and 6 months corrected age, even after taking potential risk factors into account.Conclusions: A vitamin D dose of 200 IU/kg of body weight/day up to a maximum of 400 IU/day maintains normal vitamin D status and as good a bone mineral accretion as the previously recommended higher dose of 960 IU/day. Vitamin D is a potent hormone which affects organs other than bone and should not be given in excess to preterm infants. [ABSTRACT FROM AUTHOR]