Resistance of Bordetella pertussis, the causative agent of pertussis, to erythromycin is rare. Recently, several Chinese isolates were found to be erythromycin resistant. This study aimed to investigate the occurrence of pertussis in children suffering persistent cough and the prevalence of B. pertussis resistance to erythromycin in Xi'an, China. Three hundred and thirteen patients with suspected pertussis admitted to Xi'an Children's Hospital from January 2012 through to December 2013 were included and their nasopharyngeal (NP) swabs were taken for culture and PCRs (targeting IS481 and ptx‐Pr). PCR‐based sequencing was used to identify the A2047G mutation of B. pertussis 23S rRNA directly from the NP samples. Sixteen (5.1%) and 168 (53.7%) patients were positive for culture and IS481 PCR. Of the 168 samples positive for IS481 PCR, 122 (72.6%) and 100 (59.5%) were positive for ptx‐Pr and 23S rRNA PCRs, respectively. All culture‐positive samples were also positive for the three PCRs. Fourteen (87.5%) of the 16 B. pertussis isolates were found to be resistant to erythromycin (MICs > 256 mg/L). All the 14 isolates were confirmed to have a homogeneous A2047G mutation of 23S rRNA. Of the 100 samples positive for 23S rRNA PCR, 85 (85.0%) were found to have the A2047G mutation by sequencing. Our results indicate that in Xi'an, China, pertussis remains endemic in young children, and the circulating B. pertussis strains are mostly erythromycin resistant.

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Periodontitis can exert a severe impact on the life of patients, and the use of stem cell therapy for this disease is promising. The inflammatory response consequent to periodontitis can promote stem cell proliferation. Activated inflammation triggers inhibitory cytokine secretion, thus reducing inflammation subsequent to stem cell activation. High-fluence low-power laser irradiation (HF-LPLI) has the ability to regulate stem cell function through its effect on inflammation. Thus, the aim of the present study was to examine whether HF-LPLI is able to activate stem cells to promote regeneration in periodontitis by promoting inflammation resolution, as well as to evaluate the underlying mechanism of action if an effect is observed. Stem cells were treated with HF-LPLI following inflammation activation. Reverse transcription-quantitative polymerase chain reaction and EdU assay were used to evaluate cell proliferation and differentiation. Flow cytometry and immunofluorescence were also used to detect the ability of HF-LPLI to regulate the surrounding inflammatory environment. Animal models of periodontal disease were treated with stem cells and HF-LPLI, and regeneration was detected by hematoxylin and eosin staining and in vivo imaging. It was observed that HF-LPLI promoted inflammation resolution by reducing the excessive inflammatory response, and finally stimulated stem cell proliferation and differentiation. Furthermore, in vivo results revealed that stem cells treated with HF-LPLI induced bone regeneration. HF-LPLI stimulated stem cell proliferation and differentiation by promoting inflammation resolution subsequent to stem cell activation, providing a new strategy for the clinical treatment of periodontitis.

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Background: The global prevalent ptxP3 strains varies from about 10% to about 50% of circulating B. pertussis population in different areas of China. Methods: To investigate the difference of vaccination status between different genotypes in the circulating B. pertussis after 10 years of acellular pertussis vaccine (aPV) used in China. The nasopharyngeal swabs and isolates of B. pertussis from these patients were used to perform genotyping of antigen genes. We use antibiotic susceptibility test against erythromycin and sequencing methods for site 2047 of 23S rRNA to determine the resistance status. Results: The ptxP1 allele with erythromycin resistant (ER) B. pertussis infection (total of 449 subjects) consisted of 84.70 to 96.70% from 2012 to 2016 in this study. Vaccinated with co-purified aPV was found in 133(133/403,33.0%), 1(1/9,11.1%) and 2(2/21,9.5%) in ptxP1/fhaB3-ER, ptxP1/fhaB2-ES and ptxP3/fhaB2-ES B. pertussis infected children each, which showed a significant difference (χ 2 = 6.87, P = 0.032). Conclusions: The ptxP3-ES B. pertussis was rare while the ptxP1-ER B. pertussis was steadily increased in Xi'an, China from 2012 to 2016, where co-purified aPV was prevalent used. This pose a hypothesis that the co-purified aPV might protect against ptxP3 strains more efficient, which generated a rare chance for ptxP3 strains to be under the antibiotic pressure and further developed to be erythromycin resistance. A further cohort study and the mechanisms of the additional antigen proteins of co-purified aPV protected against B. pertussis should be consideration.

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Background: The global prevalent ptxP3 strains varies from about 10% to about 50% of circulating B. pertussis population in different areas of China. Methods To investigate the difference of vaccination status between different genotypes in the circulating B. pertussis after 10 years of acellular pertussis vaccine (aPV) used in China. The nasopharyngeal swabs and isolates of B. pertussis from these patients were used to perform genotyping of antigen genes. We use antibiotic susceptibility test against erythromycin and sequencing methods for site 2047 of 23S rRNA to determine the resistance status. Results The ptxP1 allele with erythromycin resistant strains infection (total of 449 samples) consisted of 84.70% to 96.70% from 2012 to 2016. Only 2 of the 21 ptxP3 strains infected in children vaccinated with co-purified aPV, that showed a significant difference between the ptxP1 strains does (χ 2 =6.87, P=0.032). Conclusions The ptxP1 allele with erythromycin resistant B. pertussis was steadily increased in Xi’an, China from 2012 to 2016, where co-purified aPV was prevalence used . We assumed that the co-purified aPV might protect against ptxP3 strains more efficient, which generated a rare chance for ptxP3 strains to be under the antibiotic pressure and further developed to be erythromycin resistance. A further cohort study and the mechanisms of the additional antigen proteins of co-purified aPV protected against B. pertussis should be consideration.