The effect of vitamin C supplementation in the last month of pregnancy on neonatal bilirubin levels; A double-blind randomized clinical trial.

OBJECTIVES: Jaundice is a typical condition in the neonatal period, particularly in the Asian continent. Drowsiness and disruption of breastfeeding, behavioral and neurological disorders, hearing loss and mental retardation are the results of impairment in controlling it. The increase in oxidant substances can stimulate the heme oxygenase enzyme and increase the conversion of heme to bilirubin. In some studies, vitamin C levels in the blood of infants with hyperbilirubinemia were lower than in healthy infants. DESIGN: In this double-blind clinical trial study, 144 healthy pregnant women aged 20-40 years who were in 34th weeks of gestation were randomly divided into intervention, and control groups and until the end of pregnancy, they took a 500 mg tablet of vitamin C or placebo (Preparation of starch) daily. Demographic information, dietary intake, and physical activity level of the participants were also evaluated. The total blood bilirubin level was measured on the fifth day after birth using a sample of the neonatal heel. Statistical analysis was performed using SPSS software version 22. In this study P-value < 0. 05 was considered significant. RESULTS: Of the 144 participants, 128 of them completed the intervention. There was no significant difference between the two groups at the level of vitamin C intake through diet, and anthropometric indices, but the total bilirubin level in the neonates of the two groups was statistically different (P = 0.02). CONCLUSION: Vitamin C supplementation in the last month of pregnancy had a significant effect on neonatal bilirubin level and decreased it significantly.

High-level aminoglycoside resistance and distribution of aminoglycoside resistance genes among Enterococcus spp. clinical isolates in Tehran, Iran.

OBJECTIVES: Enterococci have gained attention during the past decade as important nosocomial pathogens. Their increasing prevalence has been paralleled by the occurrence of multidrug-resistant and high-level aminoglycoside-resistant strains. This study isolated Enterococcus spp. from hospital samples and determined their antibiotic resistance profile, focusing on aminoglycosides, and associated resistance mechanisms. METHODS: A total of 195 enterococci from hospital samples in Tehran were studied. Isolates were identified by biochemical reactions. Antimicrobial resistance was determined by disk diffusion. The vancomycin MIC for vancomycin-resistant isolates was determined by agar dilution. Detection of aminoglycoside resistance genes and intI1 and intI2 gene was performed by PCR. RESULTS: The majority of isolates were Enterococcus faecalis (65.1%), followed by Enterococcus faecium (31.8%), Enterococcus gallinarum (2.6%) and Enterococcus solitarius (0.5%). According to antibiogram results, 42.1% of isolates were high-level gentamicin-resistant (HLGR) and 40.5% were high-level streptomycin-resistant (HLSR). There was a high prevalence of aac(6')-Ie-aph(2")-Ia (96.3%) among HLGR isolates. ant(6)-Ia and aadA were identified in 93.7% and 64.6% of HLSR isolates, respectively. aph(2'')-Ic was detected in 7 isolates (3.6%) and aph(2'')-Ib in only 4 isolates (2.1%); no isolates harboured aph(2'')-Id, intI1 or intI2. CONCLUSION: Multidrug resistance was higher among HLGR and HLSR isolates compared with non-HLGR and non-HLSR isolates, which may result in limited treatment options. More than 50% of isolates were susceptible to aminoglycosides, thus correct identification in clinical laboratories and administration of these antibiotics can result in decreased used of antibiotics such as vancomycin and linezolid and help to reduce the emergence of resistance to these drugs.

Mannitol decreases neocortical epileptiform activity during early brain development via cotransport of chloride and water.

Seizures and brain injury lead to water and Cl- accumulation in neurons. The increase in intraneuronal Cl- concentration ([Cl-]i) depolarizes the GABAA reversal potential (EGABA) and worsens seizure activity. Neocortical neuronal membranes have a low water permeability due to the lack of aquaporins necessary to move free water. Instead, neurons use cotransport of ions including Cl- to move water. Thus, increasing the extracellular osmolarity during seizures should result in an outward movement of water and salt, reducing [Cl-]i and improving GABAA receptor-mediated inhibition. We tested the effects of hyperosmotic therapy with a clinically relevant dose of mannitol (20 mM) on epileptiform activity, spontaneous multiunit activity, spontaneous inhibitory post-synaptic currents (sIPSCs), [Cl-]i, and neuronal volume in layer IV/V of the developing neocortex of C57BL/6 and Clomeleon mice. Using electrophysiological techniques and multiphoton imaging in acute brain slices (post-natal day 7-12) and organotypic neocortical slice cultures (post-natal day 14), we observed that mannitol: 1) decreased epileptiform activity, 2) decreased neuronal volume and [Cl-]i through CCCs, 3) decreased spontaneous multi-unit activity frequency but not amplitude, and 4) restored the anticonvulsant efficacy of the GABAA receptor modulator diazepam. Increasing extracellular osmolarity by 20 mOsm with hypertonic saline did not decrease epileptiform activity. We conclude that an increase in extracellular osmolarity by mannitol mediates the efflux of [Cl-]i and water through CCCs, which results in a decrease in epileptiform activity and enhances benzodiazepine actions in the developing neocortex in vitro. Novel treatments aimed to decrease neuronal volume may concomitantly decrease [Cl-]i and improve seizure control.