Effects of a nutrient-dense formula compared with a post-discharge formula on post-discharge growth of preterm very low birth weight infants with extrauterine growth retardation: a multicentre randomised study in China.

BACKGROUND: Post-discharge optimal growth and nutritional intake have beneficial effects for neurodevelopment in preterm very low birth weight infants (VLBWIs) with extrauterine growth retardation (EUGR). The present study aimed to compare the effects of a nutrient-dense formula (NDF) to a post-discharge formula (PDF) on post-discharge growth of preterm VLBWIs with EUGR. METHODS: Forty-eight preterm VLBWIs with EUGR at discharge were randomised to receive NDF (100 kcal per 100 mL; 2.6 g protein per 100 mL) or PDF (74 kcal per 100 mL; 1.95 g protein per 100 mL) for 1-6 months until body weight reached the 50th percentile on growth charts with corrected age. Volume, nutrient intake, anthropometry and biochemistry data were collected. RESULTS: Volume intake was lower in the NDF group than the PDF group during the first 2 months of feeding (P = 0.039 and 0.018, respectively).There were no significant differences in volume intake during months 2-6 of feeding. Energy, protein, carbohydrate and fat intake were higher in the NDF group during months 1-6 of feeding. There were no significant differences in weight, length, and head circumference Z-scores during months 1-6 between the two groups. The △length Z-score from discharge to month 6 was significantly higher in the NDF group than the PDF group (P = 0.043). No differences existed between the two groups with respect to biochemistry. CONCLUSIONS: After discharge, preterm VLBWIs with EUGR fed a NDF gain anthropometric parameter Z-scores similar to those for a PDF within 6 months of follow-up. A NDF leading to gain in length requires further follow-up.

Perindopril inhibits myocardial apoptosis in mice with acute myocardial infarction through TLR4/NF-κB pathway.

OBJECTIVE: To explore the anti-apoptotic effect of perindopril on myocardial cells in mice with acute myocardial infarction (AMI). MATERIALS AND METHODS: A total of 48 mice were randomly divided into 4 groups before intervention, namely sham operation group (Sham group, n=12), AMI group (n=12), 1.5 mg/kg perindopril treatment group (Perindopril group, n=12), and 1.5 mg/kg perindopril treatment and Toll-like receptor-4 (TLR4) knockout group (TLR4-/-Perindopril group, n=12). Mice in the control group and AMI group were gavaged with normal saline, and those in the Perindopril group and TLR4-/-Perindopril group were gavaged with perindopril for 7 d. On the 4th day after drug administration, mice in the AMI group, Perindopril group and TLR4-/-Perindopril group were subjected to the ligation of the anterior descending coronary artery to induce AMI, and those in the Sham group underwent the same operation, but had a loose knot at the anterior descending coronary artery. At 24 h after the above operation, color echocardiography was performed on mice to observe changes in cardiac function. Then, the mice were sacrificed. Terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate (dUTP)-biotin nick end labeling (TUNEL) assay was carried out to determine myocardial apoptosis. Immunohistochemistry and Western blotting technique were employed to detect the protein expression levels of B-cell lymphoma 2 (Bcl-2), Bcl-2-associated X protein (Bax), TLR4 and nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p50 in infarction zones. The messenger ribonucleic acid (mRNA) expression levels of TLR4 and NF-κB p50 in infarction zones were measured via Reverse Transcription-Polymerase Chain Reaction (RT-PCR). RESULTS: Perindopril could significantly reduce the number of apoptotic myocardial cells after AMI. Mouse echocardiography showed that ejection fraction (EF), left ventricular fractional shortening (FS), left ventricular end-systolic diameter (LVESD) and left ventricular end-diastolic diameter (LVEDD) of AMI mice in the Perindopril groups were markedly superior to those in the AMI group. AMI mice in the Perindopril group had decreased expression levels of Bax protein and TLR4 and NF-κB p50 mRNA and protein, as well as the Bax/Bcl-2 ratio. Knockout of TLR4 attenuated the effect of perindopril in alleviating myocardial apoptosis after AMI. CONCLUSIONS: Perindopril inhibits myocardial apoptosis in mice with AMI through the TLR4/NF-κB pathway.

Inhibition of cytochrome P450 2A participating in coumarin 7-hydroxylation in pig liver microsomes.

Five commonly used human cytochrome P450 (CYP) inhibitors were examined for their effects on coumarin 7-hydroxylase (CYP2A) activity in pig liver microsomes. The K(m) and V(max) values for coumarin 7-hydroxylation in pig liver microsomes were estimated to be 1 µm and 0.26 nmol·mg/min, respectively. The following human CYP inhibitors caused little or no inhibition of CYP2A as defined by a K(i) > 200 µm: quinidine (CYP2D6), troleandomycin (CYP3A4), and sulfaphenazole (CYP2C9). The other two human CYP inhibitors were classified as strong inhibitors of CYP2A: 8-methoxypsoralen (CYP2A6) and α-naphthoflavone (CYP1A1/2). In the absence of a preincubation period, 8-MOP inhibited the 7-hydroxylation of coumarin with a K(i) value of 1.1 µm, which decreased to 0.1 µm when 8-MOP was preincubated with pig liver microsomes for 3 min. α-Naphthoflavone inhibited the 7-hydroxylation of coumarin with a K(i) value of 32 µm, which did not increase ability to inhibitor CYP2A when α-naphthoflavone was preincubated with pig liver microsomes for 3 min. These results of this study suggest that 8-MOP is a potent, mechanism-based inhibitor of pig CYP2A activity in pig liver microsomes.

Analytical determination and pharmacokinetics of major metabolites of carbasalate calcium in broilers following oral administration.

As a newer anti-inflammatory agent, carbasalate calcium is used in various animal species. In this study, the pharmacokinetics of carbasalate calcium was investigated in broilers. Broilers, with body weight of 2.0 ± 0.3 kg, were administrated carbasalate calcium soluble powder at a single dose of 40 mg/kg body weight orally. The plasma concentrations of its metabolites, aspirin (ASA), salicylic acid (SA) and gentisic acid (GA) were determined by LC-MS/MS method and the pharmacokinetic parameters were calculated by noncompartmental analysis. After oral administration of carbasalate calcium, the plasma drug concentration for ASA, SA and GA reached a peak (C(max) ) of 8.88 ± 1.31, 42.6 ± 4.62 and 10.1 ± 2.16 µg/mL at 0.170, 2.00 and 2.00 h, respectively. The terminal half-life (t(1/2λz) ) of ASA, SA and GA was 11.2 ± 8.04, 23.7 ± 17.1 and 28.6 ± 4.90 h, respectively. In conclusion, analytical method for the quantification of ASA, SA and GA in plasma in the broilers was developed and validated. In broilers, carbasalate calcium is quickly metabolized in ASA and ASA is rapidly converted to SA and one of the metabolites of SA is GA.

Bistability in scanning tunneling spectroscopy of Ga-terminated Si(111)

Bistable electron transport, a phenomenon usually associated with double-barrier structures, has been observed with a conventional STM junction formed between a metal tip and a Ga-terminated Si(111) surface at 77 K. Large hysteresis loops appear in the current-voltage characteristics when electrons are injected from the tip to the surface. The turn-on bias varies from -3.1 to -4.0 V and shows an inverse dependence on the tip-sample distance, indicating a strong field effect. The turn-off bias, however, is essentially pinned at a conductance threshold of -2.7 V.