Identification and analysis of 2 Corynebacterium diphtheria strains in Guangdong Province / 中华预防医学杂志

Objective: To identify and analyze two strains of C. diphtheriae in Guangdong Province by combining whole genome sequencing with traditional detection methods. Methods: The C. diphtheriae was isolated from Guangzhou in 2010 and Zhuhai in 2020 respectively. Isolates were identified by API Coryne strips and MALDI-TOF-MS. Genomic DNA was sequenced by using Illumina. The assembly was performed for each strain using CLC software. J Species WS online tool was used for average nucleoside homology identification, then narKGHIJ and tox gene were detected by NCBI online analysis tool BLSATN. MEGA-X was used to build a wgSNP phylogenetic tree. Results: GD-Guangzhou-2010 was Belfanti and GD-Zuhai-2020 was Gravis. ANIb between GD-Guangzhou-2010 and C. belfantii was 99.61%. ANI between GD-Zhuhai-2020 and C. diphtheriae was 97.64%. BLASTN results showed that the nitrate reduction gene narKGHIJ and tox gene of GD-Guangzhou-2010 was negative, while GD-Zhuhai-2020 nitrate reduction gene narKGHIJ was positive. There were two obvious clades in wgSNP phylogenetic tree. The first clades included all Mitis and Gravis types strains as well as GD-Zhuhai-2020. The second clades contained all isolates of C.belfantii, C.diphtheriae subsp. lausannense and GD-guangzhou-2010. Conclusion: Two non-toxic C. diphtheriae strains are successfully isolated and identified. The phylogenetic tree suggests that GD-Guangzhou-2010 and GD-Zhuhai-2020 are located in two different evolutionary branches.

Value and evaluation of hilar surgical approach in hilar biliary stricture / 中国实用外科杂志

Hilar biliary stricture is usually divided into malignant stricture and benign stricture. How to effectively deal with hilar biliary stricture has always been the focus in biliary surgery. Because it involves bile duct, hepatic artery,portal vein and liver parenchyma, the choice of surgical path is very important. The approach based on perihilar surgical technique can better expose the operative area and have the advantage of performing precise treatment, thus effectively improving the radical cure rate of hilar cholangiocarcinoma and reducing the surgical difficulty.

Comparison of antibiotic resistance spectrum between methicillin-resistant and methicillin-susceptible coagulase-negative staphylococci nasal isolates among 1 001 HIV infectors / 中华疾病控制杂志

Objective We aimed to elucidate the prevalence and the antibiotic resistance spectrum of nasal coagulase-negative staphylococci (CoNS) colonization among HIV infectors in Guangzhou. Method After isolation and identification, all CoNS isolates were tested for the antibiotic susceptibility, and the antibiotic resistance genes. Result Among the 1 001 HIV infectors, the prevalence of CoNS and MRCoNS were 57.44% and 48.15%, respectively. The three predominant resistant antibiotics of MRCoNS isolates were penicillin, erythromycin and trimethoprim-sulfame thoxazole, while predominant detection rates of genes were Aac(6’)-aph(2’)、ermC and linA genes. The multidrug resistance rate of MRCoNS isolates were significantly higher than methicillin-susceptible coagulase-negative staphylococci (MSCoNS) isolates (80.69% versus 39.66%, P<0.001, OR=6.36). Conclusions The prevalence and multidrug resistant rates of nasal colonization CoNS and MRCoNS are high among HIV infectors in Guangzhou. MRCoNS isolates were 6.36 times more likely to be of multidrug resistance than MSCoNS isolates.