Low doses of acetaminophen produce antidepressive-like effects through the opioid system in mice.

Acetaminophen (paracetamol) is one of the most popular analgesics for the management of fever and pain but few reports have investigated its antidepressant-like effect. Moreover, the role of the opioidergic pathway has been indicated in depression pathophysiology. This study aimed to examine the involvement of the opioid receptors in the antidepressant-like effect of acetaminophen after acute and sub-chronic administration using mice forced swimming test (FST). Our finding showed that administration of acetaminophen (50 and 100 mg/kg, i.p.) 30 min before the FST produced an antidepressant effect which was reduced by naloxone (1 mg/kg, i.p., a nonselective opioid receptor antagonist). Moreover, we observed that acetaminophen in higher doses (200 and 400 mg/kg) was ineffective. Also, the response of the non-effective dose of acetaminophen (25 mg/kg) was potentiated by the non-effective dose of morphine (0.1 mg/kg) in the FST that was antagonized by naloxone. Also, in contrast to morphine (10 mg/kg), acetaminophen (100 mg/kg, i.p.) induced neither tolerance to the anti-immobility behavior nor withdrawal syndrome after repeated administration. In addition, RT-PCR showed that hippocampal mu- and kappa-opioid receptor mRNA expression increased in mice after repeated administration of acetaminophen; however, morphine therapy for 6 days did not affect kappa-opioid receptor expression. Our findings demonstrated that acetaminophen in lower doses but not high doses revealed an antidepressant-like activity without inducing tolerance and withdrawal syndromes. Moreover, the observed effect of acetaminophen may be via altering the opioid system, particularly hippocampal mu- and kappa-receptors.

Tradeoffs between Radiation Exposure to the Lens of the Eyes and Diagnostic Image Quality in Pediatric Brain Computed Tomography.

Background: Computed tomography (CT) of the brain is associated with radiation exposure to the lens of the eyes. Therefore, it is necessary to optimize scan settings to keep radiation exposure as low as reasonably achievable without compromising diagnostic image information. The aim of this study was to compare the effectiveness of the five practical techniques for lowering eye radiation exposure and their effects on diagnostic image quality in pediatric brain CT. Methods: The following scan protocols were performed: reference scan, 0.06-mm Pbeq bismuth shield, 30% globally lowering tube current (GLTC), reducing tube voltage (RTV) from 120 to 90 kVp, gantry tilting, and combination of gantry tilting with bismuth shielding. Radiation measurements were performed using thermoluminescence dosimeters. Objective and subjective image quality was evaluated. Results: All strategies significantly reduced eye dose, and increased the posterior fossa artifact index and the temporal lobe artifact index, relative to the reference scan. GLTC and RTV increased image noise, leading to a decrease signal-to-noise ratio and contrast-to-noise ratio. Except for bismuth shielding, subjective image quality was relatively the same as the reference scan. Conclusions: Gantry tilting may be the most effective method for reducing eye radiation exposure in pediatric brain CT. When the scanner does not support gantry tilting, GLTC might be an alternative.

Comparison between maternal and neonatal serum vitamin D levels in term jaundiced and nonjaundiced cases.

BACKGROUND: Neonatal jaundice is the result of an imbalance between the production and conjugation of bilirubin. Considering the multiple roles of vitamin D, lower levels of vitamin D in these cases may be associated with neonatal jaundice. The present study was undertaken for the purpose of comparing serum vitamin D levels in healthy term jaundiced and nonjaundiced newborns and their mothers. METHODS: This case-control study was conducted in 60 term newborns and their mothers from a teaching and referral children's hospital in the southwestern region of Iran, from December 22, 2013 through March 22, 2014. Neonatal and maternal blood samples were obtained and sent to the laboratory. RESULTS: The mean serum 25-hydroxy vitamin D levels of newborns and their mothers in both the case and the control groups were not significantly associated with their serum bilirubin levels. The mean of laboratory indices (calcium, phosphorus, alkaline phosphates, parathyroid hormone, and 25-hydroxy vitamin D) in mothers and newborns of the case group were nonsignificantly higher than that of the control group, but the mean vitamin D level was significantly lower among newborn cases compared with the controls (p<0.05). CONCLUSION: Newborn vitamin D levels were significantly lower in jaundiced cases compared with those in the nonjaundiced healthy groups, which may reveal an association between indirect hyperbilirubinemia and serum vitamin D levels. We suggest that more studies should be conducted including follow-up after 15 days of age, when jaundice has typically been resolved, and before starting vitamin D supplementation.