Ascorbic Acid Concentrations in Umbilical Cord Veins and Arteries of Preterm and Term Newborns
Bibliographic record
Abstract
Ascorbic acid (AA) is a powerful antioxidant required for the defense against oxidative stress. At present it is not known whether AA may play a role in the developmental process of the fetus. We therefore determined the relationship of AA levels between the umbilical cord vein (UCV) and umbilical cord artery (UCA) of preterm ( < 37 weeks of gestation) and term ( > or = 37 weeks of gestation) infants and compared those levels to matched maternal venous AA levels. We also assessed the association between UCV plasma AA levels with birth weight and gestational age by measuring AA in 88 UCV plasma samples and 58 UCA plasma samples obtained from newborn infants ranging in gestational age from 24 to 42 weeks and birth weight from 675 to 5,020 g, by high pressure liquid chromatography. Maternal venous samples were collected at the time of delivery. The mean UCV plasma AA levels (mg/dl) were significantly lower in the preterm group than in the term group (0.43 +/- 0.59 and 1.16 +/- 0.97, respectively; p < 0.002); however, the mean UCA plasma AA levels did not differ between the groups. In contrast, mean maternal venous plasma AA levels of the preterm group (1.33 +/- 0.62) were significantly higher than those of the mothers in the term group (0.72 +/- 0.69; p < 0.01). A direct correlation was found between UCV levels and birth weight (r = 0.23, p < 0.05), and UCV levels and gestational age (r = 0.23, p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.002 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".