Aedes albopictusis a very important vector for pathogens of many infectious diseases including dengue fever. In this study, we explored the genetic polymorphism ofAedes albopictusstrains in different geographical regions using DNA barcoding of mitochondrial COI (MT-COI) gene. We collectedMT-COIsequence of 106Aedes albopictusmosquitos from 6 provinces in China including Fujian, Guangdong, Hainan, Yunnan, and Taiwan. The length of the sequences is 709bp with the content of A+T (67.7%) greater than that of G+C (32.3%). We identified mutations in 90 (13.68%) loci, of which 57 (63.33%) are transitions, 28 (31.11%) are transversions, and 5 (5.56%) are hypervariable loci. In addition, we obtained 42 haplotypes, 4 (9.52%) of which are shared among different populations. The haplotype diversity ofAedes albopictusis 0.882 and nucleotide diversity is 0.01017. Moreover, the pedigree network diagram shows that most haplotypes are under parallel evolution, suggesting a local expansion ofAedes albopictusin history. Finally, the Neighbor-Joining tree ofMT-COIhaplotypes reveals a certain correlation between haplotype clusters and geographical distribution, and there are differences amongAedes albopictusin different geographical regions. In conclusion, DNA barcoding ofMT-COIgene is an effective method to study the genetic structure ofAedes albopictus.

Allele frequency data and forensic statistical parameters were determined for 20 autosomal short tandem repeat (STR) loci of the PowerPlex 21 System in 214 unrelated healthy individuals of a Uyghur ethnic minority group living in Xinjiang province, northwest China. A total of 232 alleles were observed with the corresponding allele frequencies ranging from 0.0023 to 0.5304. All loci were consistent with Hardy–Weinberg equilibrium (HWE) after the Bonferroni correction (p > 0.0025). The combined probability of exclusion, power of discrimination, probability of matching value were 0.999999999, 0.9999999999999999999999995, and 4.78246 × 10⁻²⁵, respectively. Our results revealed that the 20 STRs were highly polymorphic and informative, and could be suitable for forensic application, especially parentage test and personal identification. The further population comparison between the Uyghur and other 26 reference populations revealed that the loci of D13S317, TH01 and D6S1043 showed high ethnical specificity. Phylogenetic analysis based on 19 shared loci demonstrated that the Uyghur had a close genetic relationship with the Kazakh, but a distinct genetic distance with other Chinese populations from different ethnicity and regions.

Three new ursane triterpenes, 3α,19α-dihydroxy-2-nor-urs-12-en-23,28-dioic acid-23-methyl ester (1), 19α,23-dihydroxy-3-oxo-2-nor-urs-12-en-28-oic acid (2), and 2,3-seco-3-methoxy-3,19α,23-trihydroxy-urs-12-en-2-al-28-oic acid (3), were isolated from the MeOH extract of the branch barks of Davidia involucrata, together with six known compounds. Their structures were elucidated by means of various spectroscopic analyses. The isolated triterpenes provide important evolutionary and chemotaxonomic knowledge about the monotypic genus Davidia. Five of the identified compounds showed moderate cytotoxicities against the cell proliferation of SGC-7901, MCF-7, and BEL-7404 with IC₅₀ range from 7.26 to 47.41 μM.

Background: Multiple incompatibility (Inc) groups of plasmids have been identified in Enterobacteriaceae species, but there are still quite a few sequenced plasmids that could not be assigned to any known Inc groups. Methods: One IncFII_pKF727591β plasmid p205880-qnrS and two Inc_pKPHS1 plasmids p11219-CTXM and p205880-NR1 were fully sequenced in this work. Detailed genomic comparison was applied to all available sequenced plasmids of IncFII_pKF727591 or Inc_pKPHS1 group. Results: p205880-qnrS carried a novel transposon Tn6396, which was an ISKpn19-compsite transposon and represented a prototype transposable element carrying a minimum core qnrS1 module. p11219-CTXM harbored a novel transposon Tn6559, which was generated from integration of a truncated IS903D–bla_CTX-M-14–ISEcp1 unit into the Tn3-family cryptic unit transposon Tn1722. Two Inc groups, IncFII_pKF727591 and Inc_pKPHS1, of plasmids from Enterobacteriaceae species were proposed, and IncFII_pKF727591 was further grouped into two subgroups IncFII_pKF727591α and IncFII_pKF727591β. Each of the 11 IncFII_pKF727591 plasmids carried multiple accessory modules including at least one resistance module, and the relatively small IncFII_pKF727591 backbones could acquire a wealth of foreign genetic contents. The modular structures of plasmid backbones were conserved within each of IncFII_pKF727591α and IncFII_pKF727591β subgroups but dramatically different, although with similar gene organizations, between these two subgroups. The Inc_pKPHS1 backbones were conserved with respect to modular structures, and only four of the 14 Inc_pKPHS1 plasmids carried accessory modules, two of which contained resistance genes. Conclusion: A genomic comparison of sequenced Inc_pKPHS1 or IncFII_pKF727591 plasmids provides insights into modular differences and genetic diversification of these plasmids, some of which carries antimicrobial resistance genes.