Search

Objective To investigate the clinical features and risk factors of infections caused by cefepime- and ertapenem-heteroresistant Klebsiella pneumoniae (FEP-HR-KP and ETP-HR-KP, respectively). Methods We conducted a retrospective case-control study of 108 Klebsiella pneumoniae strains isolated from the body fluids of the inpatients in our hospital from January, 2014 to December, 2015. The heteroresistance of the isolated strains was detected using Kirby-Bauer disk diffusion test (K-B test) and E-test, and the results were further confirmed by population analysis profile (PAP) method. The risk factors for infections by FEP-HR-KP and ETP-HR-KP were analyzed using Chi-square test and logistic regression analysis. Results Of the total of 108 non-duplicate Klebsiella pneumoniae strains isolated, 41 (40.0%) were heteroresistant to cefepime, 63(58.3%) were heteroresistant to ertapenem, and 38 (35.2%) showed heteroresistance to both. The annual detection rate of FEP-HR-KP increased from 41.7% (20/48) in 2014 to 51.7% (31/60) in 2015, and that of ETP-HR-KP increased from 54.1% (26/48) in 2014 to 61.7% (37/60) in 2015. The strains were isolated mainly from blood specimens (25/66, 37.9%), and more than half (47/66, 71.2%) of the strains were isolated from the department of surgery. Multivariate logistic regression analysis revealed that soft tissue infection (OR=1.92, 95%CI: 0.91~3.91, P=0.049), mechanical ventilation (OR=2.45, 95%CI: 1.31~4.47, P=0.013), and use of cephalosporins (OR=2.10, 95%CI: 1.18~3.13, P=0.020) were independent risk factors for infections by FEP-HR-KP; use of cephalosporins (OR=2.08, 95%CI: 0.96~4.20, P=0.033), use of carbapenems (OR=2.52, 95%CI: 1.08~3.86, P=0.023) and drainage tube placement (OR=2.76, 95%CI: 1.49~4.90, P=0.018) were independent risk factors for ETP-HR-KP infections. Conclusion The Klebsiella pneumoniae strains isolated in our hospital show high rates of heteroresistance to cefepime and ertapenem. Avoiding unnecessary invasive operation and optimizing the use of antibiotics can help to reduce the generation of heteroresistant strains and improve the treatment efficacy for FEP-HR-KP and ETP-HR-KP infections.

Objective To establish a PCR-based capillary electrophoresis (PCR/CE) to detect Survival Motor Neuron 1 (SMN1) and Survival Motor Neuron 2 (SMN2) genes and to evaluate its performance. Methods PCR/CE and Multiplex Ligation-dependent Probe Amplification (MLPA) for SMA gene diagnosis were used to blindly test the samples in sync. The performance of PCR/CE was assessed using MLPA results as the standard. Results A total of 336 samples were included in this study, consisting of 50 homozygous deletion types (14.9%), 65 heterozygous deletion types (19.3%), and 221 non-deletion types (65.8%). The results of PCR/CE for detecting SMN1 and SMN2 copy numbers (0, 1, 2, 3, ≥ 4) were in complete agreement with the results of the MLPA. Conclusions PCR/CE for gene testing related to SMA could accurately detect copy numbers of exon 7 and exon 8 of the SMN1 and SMN2 genes (0, 1, 2, 3, ≥ 4). [ABSTRACT FROM AUTHOR]

Background: Potent antitumor responses can be induced through cytokine immunotherapy. Interleukin (IL)-2 and granulocyte-macrophage colony-stimulating factor (GM-CSF) are among the most effective cytokines to induce tumor-specific systemic immune responses and can act synergistically. To overcome the limitations of combined use of these two cytokines, we have constructed an IL2-GMCSF fusion protein and characterized its antitumor effects in this study.Methods: The expression of IL-2 receptor and GM-CSF receptor of cell lines were detected with quantitative real-time PCR. On this basis, the bioactivities of IL2-GMCSF, especially effects on DC2.4 cells were assayed. Another function of IL2-GMCSF-bridge two types of cells-was assessed by cell contact counting and cytotoxicity assays. The anti-tumor activity in vivo of IL2-GMCSF was evaluated in the melanoma model. The statistical significance among treatment groups were determined by One-Way ANOVA.Results: The fusion protein IL2-GMCSF maintained the activities of IL-2 and GM-CSF, and could significantly promote DC2.4 cell activities, including phagocytosis, proliferation and cytokine secretion. In addition to the inherent cytokine activity, IL2-GMCSF bridges direct cell-cell interactions and enhances splenocyte killing efficacy against multiple tumor cell lines in vitro. Co-injection of IL2-GMCSF and inactivated B16F10 mouse melanoma cells induced complete immunoprotective responses in about 30 % of mice.Conclusion: These results suggested that IL2-GMCSF can efficiently regulate immune responses against tumors. Furthermore, as the bridging effect relies on both IL-2R and GM-CSFR and promotes interactions between immune and tumor cells, IL2-GMCSF may be utilized as a useful tool for dissecting specific immune responses for future clinical applications. [ABSTRACT FROM AUTHOR]

Objective: To explore the clinical application of preimplantation genetic testing for monogenic disorders (PGT-M) in an unique case with Spinal muscular atrophy (SMA) type 2+0., Methods: A special SMA family presented at the Third Affiliated Hospital of Guangzhou Medical University on October 19, 2020 was selected as the study subject. Multiple ligation-dependent probe amplification (MLPA) and molecular tagging linkage analysis were carried out to identify the SMN1 genotype of the couple and their fetus. Subsequently, next-generation sequencing (NGS), molecular tagging linkage analysis, and chromosomal microarray analysis were employed to determine the haplotypes and validate the result of PGT-M on the 11 embryos derived for the couple., Results: The female partner was identified as a carrier of the rare SMN1[2+0] variant, and prenatal diagnosis confirmed the fetus to be affected by SMA. Ultimately, PGT-M has successfully selected four embryos free from the pathogenic SMN1 variants and X chromosome deletion., Conclusion: PGT-M can effectively prevent the transmission of rare genetic variants such as the SMA 2+0 subtype in the families. Above finding has provided guidance for genetic counseling and family planning for the couple.