[Association of drug resistance of Mycoplasma pneumoniae with DNA load and genotypes in children with Mycoplasma pneumoniae pneumonia].

OBJECTIVE: To investigate the association of drug resistance of Mycoplasma pneumoniae (MP) with DNA load and genotypes in children with MP pneumonia. METHODS: A total of 230 children who were hospitalized and diagnosed with MP pneumonia between January 2012 and December 2016 were enrolled. Throat swabs were collected from the 230 children, and a rapid drug sensitivity assay was used to determine the sensitivity of clinical isolates of MP to nine commonly used antibacterial agents. Quantitative real-time PCR was used to measure MP-DNA load in throat swabs. PCR sequencing was used to determine the genotype of 2063 locus of the MP 23S rRNA V domain. RESULTS: Of the 230 children, 86 (37.4%) had genotype A in 2063 locus, 134 (58.3%) had genotype G, 8 (3.5%) had genotype C, and 2 (0.9%) had genotype T. Mutant strains (genotype G+C+T) had a significantly higher MP-DNA load than wild-type strains (genotype A) (P<0.05). The strains resistant to erythromycin, azithromycin, clarithromycin, and clindamycin had a significantly higher MP-DNA load than non-resistant strains (P<0.05). MP had a high drug resistance rate to macrolide antibiotics. More than 60% of the cases with resistance to macrolides were found to have A2063G mutations. MP was rarely resistant to quinolones (less than 2%). CONCLUSIONS: Mutations in 2063 locus of the MP 23S rRNA V domain may result in the resistance of MP to macrolides and the change in DNA load and can be used as a basis for selecting drugs for MP.

[Application of Mycoplasma pneumoniae antibody and load index in the diagnosis of Mycoplasma pneumoniae pneumonia in children].

OBJECTIVE: To study the role of Mycoplasma pneumoniae (MP) load and antibody measurements in the diagnosis of MP pneumonia. METHODS: A total of 115 children with MP pneumonia and 400 healthy children were enrolled. The MP load and total antibody level were measured at different stages, and the MP load index (MPLI) was calculated. RESULTS: The cut-off value of MPLI for MP infection was 6.12. MPLI and total antibody titer increased during the course of the disease, while MP-DNA decreased rapidly. Within the same time of blood collection, the group with a higher MP load had a significantly higher total antibody titer than the group with a lower MP load (P<0.05). Within 2 weeks of the course of the disease, the negative antibody group had a significantly higher MPLI than the positive antibody group (P<0.05). CONCLUSIONS: MPLI provides a standardized quantitative value of MP-DNA and plays an important role in the early diagnosis of MP infection.

[Association between CHI3L1 SNPs and susceptibility to childhood asthma].

OBJECTIVE: To investigate the association between CHI3L1 single nucleotide polymorphisms (SNPs) and the susceptibility to childhood asthma. METHODS: A total of 316 children diagnosed with asthma between January 2011 and October 2013 and 297 healthy children were selected as asthma group and control group respectively. Peripheral blood samples were collected from all subjects. Chemiluminescence and flow cytometry were applied to measure total IgE level and the percentage of eosinophils. ELISA was used to measure YKL-40 level. Genomic DNA was extracted from peripheral blood hemocytes, and the genotype and allele frequencies at CHI3L1 SNPs rs4950928, rs10399805, and rs883125 were determined by MALDI-TOP mass spectrometry. RESULTS: The total IgE and YKL-40 levels were significantly higher in the asthma group than in the control group (P<0.05), while the percentage of eosinophils showed no significant difference between the two groups (P>0.05). The frequency of GG genotype at rs883125 in the asthma group was significantly higher than that in the control group (P<0.05). For rs4950928, the asthma group had a significantly lower frequency of CC genotype (P<0.05) but a significantly higher frequency of CG genotype (P<0.05) compared with the control group. In the asthma group, the patients with GG and CG genotypes at rs4950928 had significantly increased total IgE and YKL-40 levels compared with those with CC genotype at this locus (P<0.05). CONCLUSIONS: YKL-40 is a potential molecular biomarker for the primary diagnosis of childhood asthma. CHI3L1 SNPs rs4950928 and rs883125 may be associated with childhood asthma. G allele at rs4950928 may increase the risk of childhood asthma.

The therapeutic potential of G-CSF in pressure overload induced ventricular reconstruction and heart failure in mice.

In animal models of clinical entities causative of severe right and left ventricular (LV) pressure overload hypertrophy, increased density of the cellular microtubule network, through viscous loading of active myofilaments, causes contractile dysfunction that is normalized by microtubule depolymerization. In this study, 86 male mice were divided into seven groups. The transverse ascending aorta constriction (TAC) in six groups were performed in order to make heart failure model. Mice in each group were injected with G-CSF or/and telmisartan subcutaneously at different time respectively. Results showed that reduction in left ventricular volume and improved function persisted at 2 week, but recurrent dilatation at 4 weeks was associated with a loss of functional improvement. Compared with PBS group, the expression of VEGF protein and HIF-1 mRNA were significantly higher in mice injected with G-CSF or/and telmisartan (P<0.05). The expression of p53 mRNA, myocardial fibrosis and mortality were significantly lower in mice injected with G-CSF or/and telmisartan (P<0.05). It could be concluded that G-CSF can delay the progression of pressure overload induced ventricular reconstruction and heart failure in mice.

Multi-objective evaluation of freshly distilled brandy: Characterisation and distribution patterns of key odour-active compounds.

The characterisation and distribution patterns of key odour-active compounds in head, heart1, heart2, tail, and stillage cuts of freshly distilled brandy were investigated by gas chromatography-olfactometry-mass spectrometry coupled with aroma extract dilution analysis (AEDA) and chemometrics analysis. Results from AEDA showed that there were 50, 61, 48, 25, and 18 odour-active compounds in the head, heart1, heart2, tail, and stillage cuts, respectively. Besides, 19, 22, 11, 5, and 4 quantified compounds with odour activity values ≥ 1, respectively, were considered to be potential contributors to the aroma profile of different distillation cuts. Especially, the chemometrics analysis illustrated the heart1 fraction was characterized by 3-methylbutanol, ethyl hexanoate, 1-hexanol, ethyl octanoate, benzaldehyde, ethyl decanoate, and 2-phenylethyl acetate; (E)-hex-3-en-1-ol, (Z)-hex-3-en-1-ol, and 2-phenylethyl acetate greatly contributed to the characteristics of the heart2 cut. Furthermore, different volatile compounds with a variety of boiling points and solubilities followed diverse distillation rules during the second distillation. Our findings may provide a rational basis for concentrating more pleasant aroma components contributing to brandy.

Cost-effectiveness analysis of glecaprevir/pibrentasvir regimen for treating Chinese patients with chronic hepatitis C genotype 1 and genotype 2 infection.

BACKGROUND: Hepatitis C virus (HCV) infection is an important health threat in China to which direct acting antivirals (DAAs) are very effective. In 2019, another novel DAA glecaprevir/pibrentasvir (GLE/PIB) was officially approved. Knowledge of its cost-effectiveness would be informative for clinical decision-making but has not been evaluated. This study aims to evaluate the cost-effectiveness of GLE/PIB to inform policy-making on drug reimbursement and HCV eradication. METHODS: Markov models were developed from the payers' perspective and simulated the lifetime experience of adult patients chronically infected with HCV genotype 1 or genotype 2. Two regimens, GLE/PIB and pegylated interferon (pegIFN) plus ribavirin (RBV), were compared in cost and quality adjusted life years (QALY) with both outcomes being discounted to 2020 values. The incremental cost-effectiveness ratio (ICER) was computed to reflect the incremental benefit of GLE/PIB versus pegIFN + RBV. The robustness of the model outcomes was examined using deterministic and probabilistic sensitivity analysis (PSA) to identify influential parameters and to assess the probability of GLE/PIB being cost-effective. The GDP per capita in China in 2019 ($10,275) was used as the threshold for cost-effectiveness. RESULTS: For the entire target population, GLE/PIB was the dominant regimen attaining a cost-saving of $255 and 1.17 more QALYs relative to pegIFN + RBV. The finding was more pronounced for HCV genotype 1 infection by saving $1,656 and creating 1.37 more QALYs. At the $10,275 threshold, the probability of GLE/PIB being cost-effective was 99.32% overall and 99.85% for HCV genotype 1 infection. The age of starting DAA treatment, price of pegIFN + RBV, cost of cirrhosis treatment and duration of the GLE/PIB regimen were the five most influential factors. For the patients with HCV genotype 2 infection, the ICER of GLE/PIB was $12,914/QALY with 95% confidence interval of $4,047/QALY to $37,640/QALY. The GLE/PIB regimen statistically cannot be ruled out as a cost-effective option for HCV genotype 2 infection. CONCLUSIONS: GLE/PIB is a cost-effective strategy to treat chronic HCV genotype 1 and HCV genotype 2 infection in China. This regimen should be initiated at a younger age to maximize its value. To achieve national eradication, it may be timely to consider replacing pegIFN + RBV with DAAs, such as GLE/PIB, as the first-line treatment.

Chemosensory characteristics of regional Vidal icewines from China and Canada.

This work aimed to compare the flavor characteristics of Vidal icewines from China and Canada and to establish relationships between sensory descriptors and chemical composition. Descriptive analysis was performed with a trained panel to obtain the sensory profiles. Thirty important aroma-active compounds were quantified by four different methodologies. Partial least squares discriminant analysis was used to identify candidate compounds, which were unique to certain sensory descriptors. The sensory profiles of icewines from China were characterized by nut and honey aromas, while icewines from Canada expressed caramel and rose aromas. Nut and honey aromas had a close correlation with 1-hexanol, isoamyl acetate, phenethyl acetate and phenylethyl alcohol. Caramel aroma was correlated with ethyl esters and lactones and rose aroma was correlated with terpenes.

Characterization of the Key Aroma Compounds in Chinese Vidal Icewine by Gas Chromatography-Olfactometry, Quantitative Measurements, Aroma Recombination, and Omission Tests.

The key aroma compounds of Chinese Vidal icewine were characterized by means of gas chromatography-olfactometry (GC-O) coupled with mass spectrometry (MS) on polar and nonpolar columns, and their flavor dilution (FD) factors were determined by aroma extract dilution analysis (AEDA). A total of 59 odor-active aroma compounds in three ranks of Vidal icewines were identified, and 28 odorants (FD ≥ 9) were further quantitated for aroma reconstitution and omission tests. ß-Damascenone showed the highest FD value of 2187 in all icewines. Methional and furaneol were first observed as important odorants in Vidal icewine. Aroma recombination experiments revealed a good similarity containing the 28 important aromas. Omission tests corroborated the significant contribution of ß-damascenone and the entire group of esters. Besides, 4-hydroxy-2,5-dimethyl-3(2H)-furanone (furaneol) and 3-(methylthio)-1-propanal (methional) also had significant effects on icewine character, especially on apricot, caramel, and tropical fruit characteristics.

Comparison and chemometric analysis of the phenolic compounds and organic acids composition of chinese wines.

Characteristics of 106 wines from 5 major grape varieties and 3 typical geographic regions in China were investigated by means of profiling of organic acids and phenolic compounds analysis. An ultra-performance liquid chromatography method was developed and thus, large number of samples could be determined in a quick and reliable way. The results showed that different origins and varieties were characteristic of various profiles of organic acid and phenolic compounds. In order to investigate possible correlation between organic acids and phenolic compounds content and grape variety and/or geographical origin, analysis of variance and linear discriminant analysis (LDA) were conducted. A satisfactory LDA result for red wines according to geographic origin was obtained, in which the correct classification was 100% and the leave-one-out validation accuracy was 90%. The corresponding results of white wines were 91% and 86%, respectively. When LDA was processed, according to grape varieties, the proportionality of successfully classified wines was 96%, while the leave-one-out validation accuracy was 94%. The organic acids and phenolic compounds profiles were useful in the classification of Chinese wines according to grape variety and geographic origin.