简介：AbstractThe emergence of mobile Tigecycline-resistant tet(X3) and tet(X4) is believed to be a global threat to public health. Here, we investigated the prevalence of tet(X3) and tet(X4) in our metagenomic data of migratory birds. While tet (X4) was not identified in our samples, tet(X3) was found in two gut microbiomes of bird fecal samples, with 100% amino acid identity of sites 150–387. These results suggest that tet(X3) has been spreading into the environment for a long period of time and that there is an urgent need to control its further transmission.

简介：AbstractThe low success rates in the treatment of multidrug-resistant tuberculosis (MDR-TB) and extensively drug-resistant TB (XDR-TB), which account for 55% and 34% respectively, led the WHO to conclude that MDR/XDR-TB is a serious public health crisis. However, the virulence of MDR/XDR-Mycobacterium Tuberculosis(Mtb) has not been analyzed in details, which could provide a specific guidance for the control and prevention. In this review, we discuss different aspects of MDR/XDR-Mtb virulence and its relationship to fitness cost by probing the following questions: (1) what mediates the virulence of MDR/XDR-Mtb? (What is the relationship between fitness and virulence of Mtb? (2) Is it possible that drug-resistant Mtb(DR Mtb) can show higher fitness? (3) What is the definite effect on fitness of each drug-resistant mutant? (4) What other important factors affecting fitness in the mutant strain? (5) How to study the virulence of a large number of DR Mtb?And what prevention and control measures will be taken in the future, especially for the high virulent DR Mtb? We therefore summarized the congruent relationship between drug resistance and fitness from the global response-related genes to antibiotic resistance-contributing mutation, provided methods to explore the virulence of DR Mtb. This review may offer some critical information and concise guide to creating strategies for the prevention and control of drug-resistant Mtb.

简介：AbstractAlthough the first-line rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone regimen (R-CHOP) substantially improved outcomes for patients with diffuse large B-cell lymphoma (DLBCL), 40% of the patients suffered from relapsed/refractory disease and had poor survival outcomes. The detailed mechanism underlying R-CHOP resistance has not been well defined. For this review, we conducted a thorough search for literature and clinical trials involving DLBCL resistance. We discussed DLBCL biology, epigenetics, and aberrant signaling of the B-cell receptor (BCR), phosphatidylinositol 3-kinase (PI3K)/Akt, nuclear factor kappa light chain enhancer of activated B-cells (NF-κB), and the Janus kinase (JAK)/signal transducer and activator of transcription 3 (STAT3) pathways as defining mechanisms of DLBCL heterogeneity and R-CHOP resistance. The cell of origin, double- or triple-hit lymphoma and double-protein-expression, clonal evolution, tumor microenvironment, and multi-drug resistance help to contextualize DLBCL resistance in an (epi)genetically and biologically comparative manner. With better understanding of the biological and molecular landscape of DLBCL, a more detailed classification system and tailored treatments will ideally become available to further improve the prognosis of DLBCL patients.