Using 16S rDNA Sequencing Technology to Preliminarily Analyze Intestinal Flora in Children with Mycoplasma pneumoniae Pneumonia / 生物医学与环境科学（英文）

Objective@#We investigated changes in the intestinal flora of children with Mycoplasma pneumoniae pneumonia (MPP).@*Methods@#Between September 2019 and November 2019, stool samples from 14 children with MPP from The Fourth Hospital of Baotou city, Inner Mongolia Autonomous Region, were collected and divided into general treatment (AF) and probiotic (AFY) groups, according to the treatment of "combined Bifidobacterium, Lactobacillus, Enterococcus, and Bacillus cereus tablets live". High-throughput 16S rDNA sequencing was used to identify intestinal flora.@*Results@#Intestinal flora abundance and diversity in children with MPP were decreased. Both Shannon and Simpson indices were lower in the AF group when compared with healthy controls ( P < 0.05). When compared with healthy controls, the proportion of Enterorhabdus was lower in the AF group, while the proportion of Lachnoclostridium was higher ( P < 0.05). The proportion of Bifidobacteria and Akkermansia was lower in the AFY group but Enterococcus, Lachnoclostridium, Roseburia, and Erysipelatoclostridium proportions were higher. The proportion of Escherichia coli- Shigella in the AFY group after treatment was decreased ( P < 0.05).@*Conclusions@#The intestinal flora of children with MPP is disturbed, manifested as decreased abundance and diversity, and decreased Bifidobacteria. Our probiotic mixture partly improved intestinal flora disorders.

Establishment of a Predictive Diagnostic Model for Acute Mycoplasma Pneumoniae Infection in Elderly Patients with Community-acquired Pneumonia / 生物医学与环境科学（英文）

We established a diagnostic model to predict acute Mycoplasma pneumoniae (M. pneumonia) infection in elderly Community-acquired pneumonia (CAP) patients. We divided 456 patients into acute and non-acute M. pneumoniae infection groups. Binary logistic regression and receiver operating characteristic (ROC) curves were used to establish a predictive model. The following independent factors were identified: age ⋝ 70 years; serum cTNT level ⋝ 0.05 ng/mL; lobar consolidation; mediastinal lymphadenopathy; and antibody titer in the acute phase ⋝ 1:40. The area under the ROC curve of the model was 0.923 and a score of ⋝ 7 score predicted acute M. pneumoniae infection in elderly patients with CAP. The predictive model developed in this study has high diagnostic accuracy for the identification of elderly acute M. pneumoniae infection.

P1 gene of Mycoplasma pneumoniae in clinical isolates collected in Beijing in 2010 and relationship between genotyping and macrolide resistance / 中华医学杂志(英文版)

<p><b>BACKGROUND</b>Mycoplasma pneumoniae is a common pathogen that caused community-acquired pneumonia (CAP). P1 protein served as major adhesion and immunodominant protein in Mycoplasma pneumoniae, but little about P1 gene was learned and the relationship between P1 genotype and macrolide resistance has yet to be explored.</p><p><b>METHODS</b>The DNA sequence of the entire P1 gene from 35 strains isolated from clinical specimens collected in Beijing, China, in 2010 was determined. The resulting sequences were checked for known macrolide resistance mutations, such as A2063G, A2064G, C2617G in domain V of 23S rRNA. Antibiotic susceptibility test was done to further identify macrolide resistant strains.</p><p><b>RESULTS</b>Thirty-four clinical strains were type 1, and were identical to type 1 reference strain MP129. Only one clinical strain, MpYYM22, was type 2, and proved to be variant 2c. One synonymous point mutation in the P1 type 1 gene from two isolates was identified relative to the MP129 P1 sequence at nucleotide position (nt) 552 (C>A), while another two isolates had missense mutations at nt 2504 (G>A). This point mutation caused an amino acid change from glycine to glutamic acid. An AGT tri-nucleotide variable-number tandem repeat (VNTR), coding for serine and repeating 6-11 times, up to 15-16 times, was found in the region between the RepMP4 and RepMP2/3 elements in the 35 isolates examined. All 35 clinical strains, including MpYYM22, demonstrated macrolide resistance with the range of minimum inhibitory concentration (MIC) of erythromycin from 64 to 256 µg/ml, having an A2063G transition in domain V of the 23S rRNA gene.</p><p><b>CONCLUSIONS</b>P1 type 1 was the dominant type of Mycoplasma pneumoniae in Beijing in 2010, although variant 2c strains were present. More samples are needed to determine whether there is a relationship between the P1 genotype and macrolide resistance, as the 35 strains examined did not allow a conclusive result. However, the AGT tri-nucleotide VNTR may be a more informative locus for multi-locus VNTR analysis.</p>

Application of nested PCR and sequencing technique to detect point mutations of the 23S rRNA gene of Mycoplasma pneumoniae / 中华儿科杂志

<p><b>OBJECTIVE</b>To establish a quick method to detect drug resistance of Mycoplasma pneumoniae (MP) and study the condition of drug resistance in MP infection.</p><p><b>METHODS</b>MP 23S rRNA target gene in throat swab specimens from 200 patients with suspected MP infection was detected by using nested PCR and DNA sequencing. The result of 23S rRNA gene detection was confirmed by MP isolation and drug susceptibility test in vitro for reliability.</p><p><b>RESULTS</b>Of the 200 clinical specimens, 64 were proved to be positive for MP through MP-IgM antibody, MP specific 16S rRNA nested PCR and MP isolation . The 23S rRNA gene was amplified and the gene sequence was compared with MP reference strain in Genbank, 26 were identical to the reference strain, 38 had a point mutation in 23S rRNA. Among them, 35 had A to G mutation at position 2063, 1 had A to C mutation at position 2063 and 2 had A to G mutation at position 2064, the percentage of drug resistance was 59.4%. The sensitivity of the gene detection method was 10(2) ccu/ml and it was confirmed to be reliable by MP isolation and drug susceptibility test.</p><p><b>CONCLUSIONS</b>The gene detection method could detect MP drug resistant gene directly from clinical specimen, which has the advantages of high specificity, high sensitivity and quickness. It is of great significance for diagnosis of MP infection because MP isolation is difficult and time-consuming.</p>

Macrolide-Resistance of Mycoplasma Pnuemoniae in Respiratory Tract Infection in Children / 实用儿科临床杂志

Objective To investigate the mycoplasma pneumoniae(MP) infection of the respiratory tract infection in children,the macrolide-resistant situation and resistance mechanism of MP. Methods The cultured throat swab specimens were obtained from 80 pediatric outpatients with respiratory tract infection from Dec.2008 to Mar.2009 in Beijing friendship hospital.The 23S rRNA gene of throat swab specimens and positive-cultured specimens were amplified using nested-PCR,and the products were further verified by electrophoresis and DNA sepuencing,which were collected from the outpatients.The specimens were divided into 2 groups depending on the findings of the gene sequencing whether they had gene mutation:sensitive and resistance group.The DNA sequence of samples were compared to the sequence of MP reference strain in genbank in order to findout MP drug resistant gene.The differences in macrolids therapy were investigated between 2 groups before the throat swab obtained.The drug resistance rates were compared between outpatients and inpatients. Results Thirty-two throat swab specimens were proved to be MP by direct nested-PCR,and 8 throat speeimens were proved to be MP by isolation and culrures.Total 33 cases(including 1 was positive-culture but nagative-direct PCR) were proved to be MP positive.Sixteen were identical to the M129 standard sequence,and 17 had point mutation in gene of 23S rRNA V region.Ten had A to G mutation at position 2063,3 had A to G mutation at position 2064,2 had A to G mutation at position 2067,1 had G to A mutation at position 2062,1 had A to T mutation at position 2063.There was no significant difference between the sensitive and resistance group in whether had macrolids before the throat swab obtained(P =0.909).And there was no significant difference in MP drug resistance rate between outpatients and inpatients(P =0.459). Conclusions The major mutation were A2063G and A2064G,and A2063T,A2067G,G2062A were newly found mutation points which were possibly related to macrolids resistance.

Effect of zhidan huayu oral liquid on mycoplasmal pneumonia in mice / 中国中西医结合杂志

<p><b>OBJECTIVE</b>To study the effect of Chinese herbal medicine for activating blood circulation to remove stasis in treating mycoplasmal pneumonia (MP) in mice.</p><p><b>METHODS</b>One hundered and thirty-five BALB/C mice were randomly divided into the control group, the MP model groups IF1 and IF2, the Rexithromycin treated groups LH1 and LH2, and the Rexithromycin plus Zhidan Huayu oral liquid treated groups LZ1 and LZ2. The changes of pathologic scoring, graphic analysis and thrombus counting of lung were observed.</p><p><b>RESULTS</b>In the 3rd day of treatment, the pathologic scores in LH1 and LZ1 were significantly lower and their values of graphic analysis were significantly higher than those in IF1 (P < 0.01 and P < 0.05 respectively), but with inflammation of lung significantly milder than that in IF1. The difference of therapeutic effect between LH1 and LZ1 was insignificant. In the 4th day of treatment, pathologic scores in LZ2 was significantly lower and value of graphic analysis higher than those in IF2 respectively (P < 0.01), with the improvement better than that of LH2 (P < 0.05). In 3rd and 4th day of treatment, the difference of thrombus counting between the Rexithromycin treated groups and the model groups was insignificant (P > 0.05), but it was significantly lower in the combined treated groups than that in the model groups (P < 0.05).</p><p><b>CONCLUSION</b>Zhidan Huayu oral liquid could assist Rexithromycin to alleviate the condition of mice with MP, its mechanism may be related with the effect of reducing thrombosis and improving microcirculation.</p>

Study Status and Comparison in Pediatric Cardiopulmonary Resuscitation in Children / 实用儿科临床杂志

Since cardiopulmonary resuscitation(CPR)guidelines was constituted in 1974,it was adopted many times.The American Heart Association,in collaboration with the International Liaison Committee on Resuscitation(ILCOR),adopted new CPR science guidelines in January,2005.This article gives a short introduction of CPR,and showes the progress of several editions.