Optimal dose of meropenem for the treatment of neonatal sepsis: Dosing guideline variations and clinical practice deviations.

AIMS: Meropenem is increasingly used to treat neonatal sepsis. There are several guidelines recommending different dosing regimens of meropenem in neonates. Furthermore, deviations from these guidelines regularly occur in daily clinical practice. Therefore, the current study aimed to evaluate the variations of meropenem dosing guidelines and compare the difference between guideline and clinical practice in terms of the probability of target attainment. METHODS: This study is based on a population pharmacokinetic model. After defining the predictive performance of the model, Monte Carlo simulations were used to calculate the probability of target attainment of the currently existing dosing guidelines of meropenem and their use in daily clinical practice. RESULTS: Two guidelines and two labels were included in the Monte Carlo simulations. For 70% fT>MIC (fraction of time when the free meropenem concentration exceeded the minimum inhibitory concentration during the dosing interval), the probability of target attainment of four recommended doses ranged from 59% to 88% (MIC = 2 mg·L-1 ) and from 17% to 47% (MIC = 8 mg·L-1 ). At the clinical practice evaluation, only 20% of patients attained target exposure for the MIC of 8 mg·L-1 with 70% fT>MIC , which was much less than those found in the Food and Drug Administration labels (40%). CONCLUSION: This model-based population pharmacokinetics simulation showed that improper guidelines and/or clinical practice deviations will result in low probability of target attainment for patients infected with resistant bacteria and critically ill patients. It is important to develop and adhere to evidence-based and clinically pragmatic guidelines.

Simultaneous determination of seven effective components in Shenkui Tongmai granules based on UHPLC-MS/MS.

OBJECTIVES: The objective of the study was to establish the quality standard of the formulation of Shenkui Tongmai granules (SKTM) from the perspective of safety and effectiveness. METHODS: A sensitive and specific method to simultaneously detect seven effective components by ultra-high performance liquid chromatography-tandem-mass spectrometry (UHPLC-MS/MS) in SKTM, including calycosin 7-O-ß-d-glucopyranoside, icariin, sodium danshensu, hyperoside, astragaloside IV, hesperidin, and salvianolic acid, was developed and validated. A Kromasil 100-3.5 C18 column with a mobile phase of 6.5 mmol/l ammonium acetate in acetonitrile was used to separate these above-listed components. Gradient programming was used with a flow rate of 0.2 ml/min, and the components were achieved in 13 min. Multiple reaction monitoring (MRM) in positive/negative mode was applied for the MS/MS detection. KEY FINDINGS: The analytical method was satisfactorily validated for linearity, accuracy and precision, repeatability and stability. The developed UHPLC-MS/MS method had high repeatability and accuracy and it was in a good linear relationship within their respective ranges (r = 0.9999) with the RSD value of the sample recovery of less than 5%. CONCLUSIONS: The current method established here is suitable for use in determining seven effective components in SKTM simultaneously, which may provide a new reliable method for overall quality control of SKTM.

Population Pharmacokinetics and Dosing Optimization of Azithromycin in Children with Community-Acquired Pneumonia.

Azithromycin is extensively used in children with community-acquired pneumonia (CAP). Currently, the intravenous azithromycin is used off-label in children partly due to lacking of pharmacokinetic data. Our objective was to evaluate the population pharmacokinetics (PPK) and optimize dose strategy in order to improve treatment in this distinctive population. This was a prospective, multicenter, open-labeled pharmacokinetic study. Blood samples were collected from hospitalized pediatric patients and concentrations were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS). PPK analysis was conducted using NONMEM software. The pharmacokinetic data from 95 pediatric patients (age range, 2.1 to 11.7 years) were available for analysis. The PPK was best fitted by a two-compartment model with linear elimination. Covariate analysis verified that body weight and alanine aminotransferase (ALT) had significant effects on azithromycin pharmacokinetics, yielding a 24% decrease of clearance in patients with ALT of >40. Monte Carlo simulation showed that for children with normal liver function, a loading-dose strategy (a loading dose of 15 mg/kg of body weight followed by maintenance doses of 10 mg/kg) would achieve the ratio of the area under free drug plasma concentration-time curve over 24 h (fAUC) to MIC90 (fAUC/MIC) target of 3 h in 53.2% of hypothetical patients, using a normative MIC susceptibility breakpoint of 2 mg/liter. For children with ALT of >40, the proposed dose needed to decrease by 15% to achieve comparable exposure. The corresponding risk of overdose for the recommended dosing regimen was less than 5.8%. In conclusion, the PPK of azithromycin was evaluated in children with CAP and an optimal dosing regimen was constructed based on developmental pharmacokinetic-pharmacodynamic modeling and simulation.

Expression and regulation of pear 1-aminocyclopropane-1-carboxylic acid synthase gene (PpACS1a) during fruit ripening, under salicylic acid and indole-3-acetic acid treatment, and in diseased fruit.

In plants, the level of ethylene is determined by the activity of the key enzyme 1-aminocyclopropane-1-carboxylic acid (ACC) synthase (ACS). A gene encoding an ACC synthase protein was isolated from pear (Pyrus pyrifolia). This gene designated PpACS1a (GenBank accession no. KC632526) was 1488 bp in length with an open reading frame (ORF) encoding a protein of 495 amino acids that shared high similarity with other pear ACC synthase proteins. The PpACS1a was grouped into type-1 subfamily of plant ACS based on its conserved domain and phylogenetic status. Real-time quantitative PCR indicated that PpACS1a was differentially expressed in pear tissues and predominantly expressed in anthers. The expression signal of PpACS1a was also detected in fruit and leaves, but no signal was detected in shoots and petals. Furthermore, the PpACS1a expression was regulated during fruit ripening. In addition, the PpACS1a gene expression was regulated by salicylic acid (SA) and indole-3-acetic acid (IAA) in fruit. Moreover, the expression of the PpACS1a was up-regulated in diseased pear fruit. These results indicated that PpACS1a might be involved in fruit ripening and response to SA, IAA and disease.

Effects of guanxinping tablet containing serum on H2O2-induced apoptosis and NF-kappaB expressions in vascular endothelial cells / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the effects of Guanxinping Tablet (GT) containing serum on H2O2-induced apoptosis and the nuclear factor kappa B (NF-kappaB) expression in vascular endothelial cells (VECs).</p><p><b>METHODS</b>Rabbits were randomly divided into the normal control group (treated with normal saline, 10 mL/kg), the verapamil group (0. 02 g/kg, 10 mL/kg), the small dose GT group (2; 8 g/kg, 10 mL/kg), the middle dose GT group (5.6 g/kg, 10 mL/kg), and the large dose GT group (11.2 g/kg, 10 mL/kg), 3 in each group. The medication was given to rabbits by gastrogavage for 3 successive days. The gastrogavage was performed twice on the last day with an interval of 2 h. One h after the last medication the peripheral blood was sampled from the vein of the ear edge. The blood was put for 1 h and centrifuged at 2 500 r/min for 30 min. The serum was extracted and deactivated at 56 degrees C for 30 min to prepare the drug containing serum. The apoptosis injury model was established using 100 micromol/L H2O2 induced VECs in the log phase growth. After modeling they were divided into 6 groups, 5 samples in each group, i. e., the normal group (10% vehicle serum culture solution), the model group (10% vehicle serum culture solution +100 micromol/L H2O2), the verapamil group (10% verapamil serum culture solution +100 micromol/L H2O2), the low dose GT group (10% low dose GT culture solution +100 micromol/L H2O2), the middle dose GT group (10% middle dose GT culture solution + 100 micromol/L H2O2), and the high dose GT group (10% high dose GT culture solution + 100 micromol/L H2O2). THE VEC apoptotic rate was detected using flow cytometry. The protein expression of NF-kappaB was detected using Western blot.</p><p><b>RESULTS</b>The VEC apoptosis rate (9.00% +/- 1.18%) and the protein expression of NF-kappaB (0.39% +/- 0.06%) increased more in the model group than in the normal control group (P<0.01). Compared with the model group, the VEC apoptosis rate of the verapamil group (6.00% +/- 0.18%), the large dose GT group (5.30% +/- 0.08%), and the middle dose GT group (6.83% +/- 0.51%) were obviously lower. The expression of NF-kappaB of each treatment group significantly decreased (the verapamil group: 0.28% +/- 0.03%; the small dose GT group: 0.33% +/- 0.03%; the middle dose GT group: 0.30% +/- 0.03%; the large dose GT group: 0.28% +/- 0.04%, P<0.01, P<0.05).</p><p><b>CONCLUSIONS</b>GT could fight against H2O2-induced VEC cell apoptosis. Its mechanism might be correlated with regulating the expression of NF-kappaB protein.</p>

[Effects of Chinese herb compound Naoyikang on expression of choline acetyltransferase in brain of rats with Alzheimer's disease].

OBJECTIVE: To observe the effects of Naoyikang (NYK) on expression of choline acetyltransferase (ChAT) in brain of rats with Alzheimer' s disease (AD). METHOD: Bilateral infusions of Ibotenic acid (IBO) into nucleus basalis of Meynert (NBM) using hamilton syringe and stereotaxic apparatus were adopted to establish the rat model of AD. After intragastrically administrated with different solution for 28 days, immunohistochemistry and Western-blot were adopted to study the expression of ChAT in frontal cortex of AD rats. RESULT: NYK could improve the morphology and increase the number of ChAT immunoreactive neurons, and significantly promote ChAT protein expression. CONCLUSION: NYK may be able to increase the synthesis of acetylcholine (ACh) through elevating the expression of ChAT protein, thus improving the level of brain ACh so as to protect central cholinergic neurons.

[Clinical efficacy of Gengxueting and its effect on estrogen receptor and progesterone receptor in patients with hysteromyoma].

OBJECTIVE: To explore the clinical efficacy of Gengxueting (GXT) in treating hysteromyoma and its effects on estrogen receptor (ER) and progesterone receptor (PR). METHODS: Sixty-four hysteromyoma patients with surgical indication were equally assigned to the treated group and the control group. Patients in the treated group were treated with GXT one capsule every day for 90 consecutive days before surgical operation, while those in the control group were treated with surgery alone. Serum levels of reproductive hormones were determined in the follicular phase before medication and one day before operation by RIA, and colored Doppler ultrasound examination was conducted for measuring the size of uterus and myoma. Moreover the protein expressions of ER and PR in tumor and uterine muscular tissues were detected by immunohistochemistry assay with streptomycin avidin-biotin peroxidase complex method. RESULTS: In the treated group after medication, the serum level of estradiol was (167.0 +/- 85.9) pmol/L, progesterone (1.9 +/- 1.0) nmol/L, follicle-stimulating hormone (10.4 +/- 2.1) IU/L, and luteinizing (12.0 +/- 9. 8) IU/L, all reached the levels of early follicular phase, with the maximal size of myoma significantly decreased from (380.4 +/- 21.0) cm3 to (162.3 +/- 14. 8) cm3 (P < 0.01); and the ER and PR expressions in tumor tissue were significantly lower than those in the control group respectively (P < 0.01). CONCLUSION: Expressions of ER and PR in hysteromyoma tissue could be significantly reduced by medication of GXT, which leads to significant shrinkage of tumor size and improvement of clinical symptoms.

[Protective effect of Naoyikang on the Alzheimer's disease model mice induced by D-galactose and NaNO2].

AIM: To investigate the mechanisms of Naoyikang (Traditional Chinese Medicine) on the Alzheimer's Disease (AD) model mice induced by D-galactose (D-gal) and NaNO2. METHODS: The mouse model was established by intraperitoneal injection of D-gal and NaNO2. The capacity of learning and memory was tested on mice with electrical maze; the content of nitric oxide (NO) and the activity of monoamine oxidase-B (MAO-B), glutathione peroxidase (GSH-PX), Na(+) -K(+) -ATP enzyme and Ca(2+) -ATP enzyme in cerebral cortex and hippocampus were assayed by biochemical methods; expression of Bax and Bcl-2 mRNA was detested by RT-PCR. RESULTS: Naoyikang could ameliorate the capacity of learning and memory of AD model mice and reduce MAO-B activity in the brain tissue and activate the activity of Na(+) -K(+) -ATP enzyme and Ca(2+) -ATP enzyme in the brain tissue and decrease the expression of Bax mRNA, but increase the expression of Bcl-2 mRNA in the model brain tissue. CONCLUSION: Naoyikang could protect AD model mice induced by D-gal and NaNO2. It could modify the metabolism of monoamine neurotransmitter in brain through reducing MAO-B activity and protect neurons by activating the activity of Na(+) -K(+) -ATP enzyme and Ca(2+) -ATP enzyme and decrease Bax expression and increase Bcl-2 expression in the model brain tissue.

[Protective effect of Naoyikang on the damage induced by glutamate in hippocampal neuron].

AIM: To investigate the effect of Naoyikang serum on the damage induced by glutamate in hippocampal neuron. METHODS: Morphological observation, MTT assay and nuclear DNA-associated fluorescence with DAPI dye were applied to evaluate the viability of hippocampal neuron, immunocytochemistry and RT-PCR were used to determine the expression of PTEN. RESULTS: A decreased viability and increased expression of PTEN were shown in hippocampal neuron in response to the treatment with glutamate. It was shown that the percentage of cell death and the expression of PTEN were reduced by the treatment with Naoyikang serum. CONCLUSION: These results suggest that Naoyikang may prevent the toxicity of glutamate by suppressing the expression of PTEN.