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The epidemiological investigation and laboratory-based confirmation were performed on samples from a family botulism outbreak in Zhangjiakou, Hebei province, China. Forty-four samples, including 14 samples (leftover food, and swabs taken of both food packaging bags and dishes, and serum and vomitus of the victims) related to outbreak and 30 causative food products after outbreak, were collected and analyzed. Isolation, bacterial identification, toxin detection, and whole-genome sequencing of Clostridiumspp. cultured from the latter samples and animal assays were performed. Mice injected with the cultures of the leftover chili chicken feet, together with the inner layer of its packaging bag, the plate for serving it, and supernatant of two patients' serum that demonstrated the typical signs of botulism. The polyvalent anti-botulinum neurotoxin (BoNT) and the monovalent anti-BoNT/E exhibited protective effects when administered to mice. Three Clostridium botulinumcultures were obtained and verified to be positive for BoNT/E. The whole genome analysis of the isolates revealed that the classic bont/egene orfXcluster was found to be located on the chromosomes of all three isolates. Single nucleotide polymorphism analysis suggested that these might be from the same source. Our findings indicated that this botulism outbreak occurred following the ingestion of vacuum-packed chili chicken feet contaminated with BoNT/E produced by C. botulinum.

AbstractObjective:Laboratory-based characterization and traceback of Clostridium butyricumisolates linked to outbreak cases of neonatal necrotizing enterocolitis (NEC) in a hospital in China.Methods:In total, 37 samples were collected during the NEC outbreak. Classical bacteriological methods were applied to isolate and identify Clostridiumspp. Meanwhile, 24 samples collected after an outbreak were similarly tested. All Clostridiumisolates were identified to species level as either C. butyricumor C. sporogenes. These isolates were subsequently subtyped using pulsed-field gel electrophoresis (PFGE). Genomic DNA was purified from 2 representative C. butyricumisolates and sequenced to completion.Results:Of 37 samples collected during the NEC outbreak, 17 (45.95%) were positive for Clostridiumspp. One species, C. butyricum, was cultured from 10 samples. Another species cultured from 2 other samples was identified as C. sporogenes. Both of these species were cocultured from 5 samples. Pulsotyping showed that the 15 C. butyricumand the 7 C. sporogenesisolates produced indistinguishable DNA profiles. No NEC cases were reported after disinfection following the outbreak, and all samples collected after the outbreak were negative for Clostridiumspp. Whole-genome sequencing (WGS) indicated that sialidase, hemolysin, and enterotoxin virulence factors were located on the chromosomes of 2 C. butyricumisolates.Conclusions:The outbreak of NEC was epidemiologically linked to C. butyricumcontamination within the hospital. This is the first report of an NEC outbreak associated with C. butyricuminfection in China.

The hematopoietic system is sensitive to radiation. In this research, new aryl sulfone derivatives (XH-201 and XH-202) containing a nitrogen heterocycle were designed and synthesized and their radio-protective efficacies with regard to the hematopoietic system were evaluated. XH-201 administration significantly increased the survival rate of mice after 8.0 Gy total body irradiation (TBI). The results showed that XH-201 treatment not only increased the white blood cells, platelets counts and the percentage of hematopoietic progenitor cells and hematopoietic stem cells in mice exposed to 4.0 Gy TBI but also decreased DNA damage, as determined by flow cytometric analysis of histone H2AX phosphorylation. In addition, our data demonstrated that XH-201 decreased the mitochondrial reactive oxygen species (ROS) levels in hematopoietic cells. Overall, these data suggest that XH-201 is beneficial for the protection of the hemoatopoietic system against radiation-induced injuries.

Intestinal injury is the primary toxicity of radiotherapy for pelvic and abdominal tumors, and it is also one of the common acute complications of radiotherapy. At present, there are no effective drugs to prevent intestinal injury in the clinic. Zingerone is a natural product with radioprotective effects. In this study, a novel compound (thiazolidine hydrochloride, TZC01) was synthesized by structural modification of zingerone. The effects of TZC01 on preventing intestinal injury from radiation were further investigated in this study. C57BL/6N mice were exposed to a lethal dose of abdominal irradiation (ABI) with and without TZC01 treatments. The morphological changes of the intestine and various makers of intestinal crypt cells were investigated. Treatment with TZC01 improved the survival rate of mice exposed to 12 Gy ABI. Moreover, TZC01 protected the intestinal morphology of mice, decreased the apoptotic rate of intestinal crypt cells, maintained cell regeneration and promoted crypt cell proliferation and differentiation. This study suggests that TZC01 has preventive and therapeutic effects on radiation enteritis by promoting the proliferation and differentiation of crypt cells to protect the small intestine from the toxic effects of ionizing radiation. Furthermore, the study of TCZ01 lays a strong foundation for developing novel radioprotectors with multiple properties.

The hematopoietic system is widely studied in radiation research. Tea has been proved to have antioxidative activity. In the present study, we describe the protective effects of dark tea extract (DTE) on radiation-induced hematopoietic injury. DTE administration significantly enhanced the survival rate of mice after 7.0 and 7.5 Gy total body irradiation (TBI). The results showed that DTE not only markedly increased the numbers and cloning potential of hematopoietic cells, but also decreased DNA damages after mice were exposed to 6.0 Gy total body irradiation (TBI). In addition, DTE also decreased the levels of reactive oxygen species (ROS) in hematopoietic cells by inhibiting NOX4 expression and increasing the dismutase, catalase and glutathione peroxidase in livers. These data demonstrate that DTE can prevent radiation-induced hematopoietic syndromes, which is beneficial for protection from radiation injuries.

To develop and synthesize a novel derivative of ethyl pyruvate, named TZC02, and investigate its radioprotective effects against ionizing radiation (IR)-induced intestinal injury in mice.

Purpose: To analyze the correlation of hepatitis B virus reactivation with patient-related and treatment-related dose–volume factors and to describe the feasibility of hepatitis B virus reactivation analyzed by a normal tissue complication probability model for patients with hepatocellular carcinoma treated with radiotherapy.Materials and Methods: Ninety patients with hepatitis B virus-related hepatocellular carcinoma treated with radiotherapy were enrolled in this retrospective study and were followed from June 2009 to December 2015. Of the 90 patients, 78 had received conventional fractionation radiotherapy to a mean dose of 39.6 to 50.4 Gy and 12 patients were scheduled to receive hypofractionation. The physical doses were converted into 2 Gy equivalents for analysis. The parameters, TD50(1), n, and m, of the Lyman-Kutcher-Burman normal tissue complication probability model were derived using maximum likelihood estimation. Bootstrap and leave-one-out were employed to against model overfitting and improve the model stability.Results: Radiation-induced liver diseases were 17.8%, hepatitis B virus reactivation was 22.2%, and hepatitis B virus reactivation-induced hepatitis was 21.1%, respectively. In multivariate analysis, the V5Gywas associated with hepatitis B virus reactivation; TD50(1), m, and nwere 32.3, 0.55, and 0.71 Gy, respectively, for hepatitis B virus reactivation. Bootstrap and leave-one-out results showed that the hepatitis B virus parameter fits were extremely robust.Conclusion: A Lyman-Kutcher-Burman normal tissue complication probability model has been established to predict hepatitis B virus reactivation for patients with hepatocellular carcinoma who received radiotherapy.