[Quantitative risk assessment of occupational exposure to PCDD/Fs in the waste incineration industry].

Objective: To analyze the level of PCDD/Fs exposure of occupational workers in the waste incineration industry and explore the risk of occupational exposure. Methods: In September 2021, literature on environmental PCDD/Fs exposure in waste incineration plants published from the establishment of the database to February 10, 2021 was retrieved from CNKI database. A total of 1365 literatures were retrieved, and 7 met the criteria for inclusion. The US Environmental Protection Agency (EPA) inhalation risk model was used to assess and analyze carcinogenic and non-carcinogenic risks of PCDD/Fs exposure among occupational workers in the waste incineration industry. Results: A total of 86 sampling sites were included in incineration plants in 7 regions. The study of Wuhan area showed that the concentration of working environment near the waste incinerator in the same factory was the highest, followed by the rest and office area in the factory. The concentration of PCDD/Fs in waste incinerators was the highest in Southwest China (4880.00-24880.00 pg TEQ/m(3)), and the lowest in Shenzhen (0.02-0.44 pg TEQ/m(3)). According to the cancer risk assessment, with the increase of exposure years, the risk of cancer increased. The highest risk of cancer was found in the waste incineration plants in Southwest China. When the exposure period was 1 year, the risk was moderate (22.40×10(-6)-114.20×10(-6)). When the exposure time was more than 5 years, the risk of cancer was high. In Jinan, workers working near the incinerator had a moderate risk of cancer after five years of exposure. In Zhejiang, workers were at medium risk of cancer after exposure for more than 20 years. Workers in Wuhan, Shanghai, Zhejiang Province, Shenzhen and the Pearl River Delta were still at low risk of cancer after 40 years of occupational exposure. HQ>1 of workers working near the waste incinerators in Jinan, Zhejiang Province and Southwest China, and the qualitative evaluation results showed that the non-carcinogenic risk was unacceptable. Conclusion: There are great differences in PCDD/Fs of occupational exposure in waste incineration industry, and the occupational exposure exceeding the occupational exposure limit has higher carcinogenic and non carcinogenic risks.

[Mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 regimen in the treatment of pediatric Burkitt lymphoma].

Objective: To analyze the clinical characteristics of children with Burkitt lymphoma (BL) and to summarize the mid-term efficacy of China Net Childhood Lymphoma-mature B-cell lymphoma 2017 (CNCL-B-NHL-2017) regimen. Methods: Clinical features of 436 BL patients who were ≤18 years old and treated with the CNCL-B-NHL-2017 regimen from May 2017 to April 2021 were analyzed retrospectively. Clinical characteristics of patients at disease onset were analyzed and the therapeutic effects of patients with different clinical stages and risk groups were compared. Survival analysis was performed by Kaplan-Meier method, and Cox regression was used to identify the prognostic factors. Results: Among 436 patients, there were 368 (84.4%) males and 68 (15.6%) females, the age of disease onset was 6.0 (4.0, 9.0) years old. According to the St. Jude staging system, there were 4 patients (0.9%) with stage Ⅰ, 30 patients (6.9%) with stage Ⅱ, 217 patients (49.8%) with stage Ⅲ, and 185 patients (42.4%) with stage Ⅳ. All patients were stratified into following risk groups: group A (n=1, 0.2%), group B1 (n=46, 10.6%), group B2 (n=19, 4.4%), group C1 (n=285, 65.4%), group C2 (n=85, 19.5%). Sixty-three patients (14.4%) were treated with chemotherapy only and 373 patients (85.6%) were treated with chemotherapy combined with rituximab. Twenty-one patients (4.8%) suffered from progressive disease, 3 patients (0.7%) relapsed, and 13 patients (3.0%) died of treatment-related complications. The follow-up time of all patients was 24.0 (13.0, 35.0) months, the 2-year event free survival (EFS) rate of all patients was (90.9±1.4) %. The 2-year EFS rates of group A, B1, B2, C1 and C2 were 100.0%, 100.0%, (94.7±5.1) %, (90.7±1.7) % and (85.9±4.0) %, respectively. The 2-year EFS rates was higher in group A, B1, and B2 than those in group C1 (χ2=4.16, P=0.041) and group C2 (χ2=7.21, P=0.007). The 2-year EFS rates of the patients treated with chemotherapy alone and those treated with chemotherapy combined with rituximab were (79.3±5.1)% and (92.9±1.4)% (χ2=14.23, P<0.001) respectively. Multivariate analysis showed that stage Ⅳ (including leukemia stage), serum lactate dehydrogenase (LDH)>4-fold normal value, and with residual tumor in the mid-term evaluation were risk factors for poor prognosis (HR=1.38,1.23,8.52,95%CI 1.05-1.82,1.05-1.43,3.96-18.30). Conclusions: The CNCL-B-NHL-2017 regimen show significant effect in the treatment of pediatric BL. The combination of rituximab improve the efficacy further.

[Pulmonary extranodal natural killer/T-cell lymphoma: clinical analysis of three cases].

Objective: To improve the understanding of pulmonary involvement of extranodal natural killer/T-cell lymphoma (ENKTL) by analyzing the clinical manifestations, imaging and pathological features of this disease. Methods: Three cases of ENKTL, proven by pathological diagnosis in Fuzhou General Clinical Medical College of Fujian Medical University, were retrospectively analyzed. Results: All of the 3 cases were males, aged 74, 61 and 49 years, respectively. The main clinical symptoms included cold and fever. One patient had nasal congestion and runny nose. Chest CT showed multiple lung nodules (n=3), masses (n=2) and patchy shadows (n=2), with irregular lesions and clear boundaries. The 3 cases had been misdiagnosed as community acquired pneumonia, and treated with intravenous injection of moxifloxacin. ENKTL was confirmed by CT-guided percutaneous biopsy with immunohistochemical staining, which showed that 3 cases were positive for CD(56), CD(2), in situ hybridization for EBV encoded RNA (EBER), while negative for CD(20), and 2 cases were positive for CD(3), Granzyme B; and 1 case was positive for T-cell intracytoplasmic antigen-1. All 3 patients received chemotherapy, but 2 patients died, one of rejection 1 month later after bone marrow transplantation. One patient had improved after chemotherapy with follow-up. Conclusion: ENKTL should be considered when patients presented with fever, multiple lung nodules or consolidations which were non-responsive to antibiotics. Lung biopsy was the key to diagnosis.

Avian sarcoma and leukosis virus gag gene in the Anser anser domesticus genome.

Endogenous retroviruses are regarded as ideal genetic markers for evolutionary analyses. Birds were some of the initial vertebrates found to contain endogenous retroviruses. However, few studies have investigated the presence and distribution of endogenous retroviruses in goose. In this study, we detected the avian sarcoma and leukosis virus gag gene in the genomic DNA of 8 Chinese native breeds using polymerase chain reaction method. The results indicated that a 1.2-kb avian sarcoma and leukosis virus gag sequence was integrated into all 8 goose breeds. The mean genetic pairwise distance was 0.918% among the investigated geese. To the best of our knowledge, this is the first report demonstrating the presence of the endogenous retroviruses in the domestic goose genome. The genetic structure should be further examined in the domestic goose.

Radiation-induced metabolomic changes in sterile male Μοnochamus alternatus (Coleoptera: Cerambycidae).

Radiation-induced sterile insect technique is a biologically based, environment-friendly method for the suppression or eradication of a number of insect pests. Although the basic mechanisms underlying the technology have been well studied, little is known about the cell responses in organisms. Characterization of the metabolic shift associated with radiation exposure in sterile insects would be helpful for understanding the detailed mechanism underlying this technique and promote its practical application. In this article, a metabolomic study was performed to characterize the global metabolic changes induced by radiation using untreated and 40 Gy (60)Coγ-irradiated testes of Japanese pine sawyer, Monochamus alternatus Hope. Differential metabolites were detected and tentatively identified. Many key metabolites in glycolysis and the tricarboxylic acid cycle, as well as most fatty and amino acids, were elevated in irradiated male M. alternatus, presumably resulting from depression of glycolysis and the tricarboxylic acid cycle, each of which are important pathways for energy generation Adenosine Triphosphate (ATP) in insect spermatozoa. The findings in this article will contribute to our knowledge of the characteristic metabolic changes associated with irradiation sterility and understand the molecular mechanisms underlying radiation-induced sterile insect technique.

Differential expression of Toll-like receptor genes in lymphoid tissues between Marek's disease virus-infected and noninfected chickens.

Toll-like receptors (TLR) are trans-membrane sensors recognizing invading microbes. Toll-like receptors play a central role in initiating immune responses against several pathogens. In this study, we investigated the response of TLR and downstream genes to Marek's disease virus (MDV) infection. Forty 1-d-old chicks were randomly divided into 2 groups, with 20 chicks infected with MDV and 20 chicks mock-infected. Four chickens were euthanized respectively from infected and age-matched noninfected groups at 4, 7, 14, 21, and 28 d postinfection (dpi). Bursas, spleens, and thymuses were removed. The differential expression of TLR genes, including TLR3, TLR5, TLR7, TLR15, and TLR21, and downstream genes of TLR7, including MyD88, TRAF3, TRAF6, IFNA, IFNB, and IL6, in lymphoid tissues of MDV-infected and noninfected chickens was determined by real-time PCR. The results showed that the change of TLR genes was different in 3 lymphoid tissues. Expression of TLR7 and MyD88 was upregulated at 14 dpi and downregulated at 28 dpi in MDV-infected compared with noninfected spleens. The TRAF6 and IFNB were upregulated, and TRAF3, IFNA, and IL6 genes showed increasing trends in MDV-infected compared with noninfected spleens at 14 dpi. The expression of TLR3 and TLR15 genes was downregulated in MDV-infected compared with noninfected spleens at 28 dpi. The results indicated that TLR7 and its downstream genes were a response to MDV infection at 14 dpi. However, the function of TLR was impaired when the infection entered the tumor transformation phase. In bursas, TLR3 and TLR15 genes were upregulated at 7 and 4 dpi, respectively. It indicated that TLR3 and TLR15 might be involved in response to MDV infection in bursa at early phases. However, no differential expression of TLR genes was observed between MDV-infected and noninfected thymuses, which indicated that the thymus had little response to MDV infection mediated by TLR.

A genome-wide SNP scan reveals two loci associated with the chicken resistance to Marek's disease.

Marek's disease (MD) is a neoplastic disease in chickens, caused by the Marek's disease virus (MDV). To investigate host genetic resistance to MD, we conducted a genome-wide association study (GWAS) on 67 MDV-infected chickens based on a case and control design, including 57 susceptible chickens in the case group and 10 resistant chickens as controls. After searching 38 655 valid genomic markers, two SNPs were found to be associated with host resistance to MD. One SNP, rs14527240, reaching chromosome-wide significance level (P < 0.01) was located in the SPARC-related modular calcium-binding 1 (SMOC1) gene on GGA5. The other one, GGaluGA156129, reaching genome-wide significance (P < 0.05), was located in the protein tyrosine phosphatase, non-receptor type 3 (PTPN3) gene on GGA2. In addition, expression patterns of these two genes in spleens were detected by qPCR. The expression of SMOC1 was significantly up-regulated (P < 0.05), whereas the expression of PTNP3 did not show significance when the case group was compared with the control group. Up-regulation of SMOC1 in susceptible spleens suggests its important roles in MD tumorigenesis. This is the first study to investigate MD-resistant loci, and it demonstrates the power of GWASs for mapping genes associated with MD resistance.

Gene expression analysis of host spleen responses to Marek's disease virus infection at late tumor transformation phase.

Marek's disease is a viral neoplastic disease of chickens caused by Marek's disease virus (MDV). Gene expression patterns have been investigated at different MDV infection stages, but there is limited research about the late tumor transformation phase. In this experiment, 44K Agilent chicken genome-wide expression microarrays were used to profile differential expression in tumorous spleens (TS) from severely morbid chickens and apparently normal spleens from survivors (SS) after MDV infection and expression in noninfected spleens (NS) from controls. There were 4,317 differentially expressed (DE) genes in TS versus NS. However, no DE genes were detected in SS versus NS, suggesting that maintenance of, or return to, homeostasis of gene activity in survivor spleens. Downregulated genes in tumorous spleens mainly enriched in the cytokine-cytokine receptor interaction pathway, and commonly investigated genes in Marek's disease study, IL6, IL18, IFNA, and IFNG were nondifferentially expressed, which indicates host inflammatory response was impaired. The IL10 and TNFRSF8 genes were upregulated in tumorous spleens. We speculated that IL10 might be exploited by MDV to escape from host immune surveillance, as reported for Epstein-Barr virus, which stimulated T cells secreting IL10 to subvert immune response. Previous study reported that transcription from TNFRSF8 promoter could be enhanced by MDV oncogene Meq. In this study, the increased expression of TNFRSF8 indicated interaction between MDV and TNFRSF8, which might facilitate pathogenesis and tumor transformation. The expression of many members in IGF system was changed in tumorous compared with noninfected spleens. The downregulation of IGFBP7 was considered to be associated with MD lymphoma transformation. Gene expression change of multiple regulatory pathways indicated their involvements in facilitating tumor transformation.

The refolding, purification, and activity analysis of a rice Bowman-Birk inhibitor expressed in Escherichia coli.

A putative rice trypsin/chymotrypsin inhibitor of the Bowman-Birk family, RBBI-8 of about 20 kDa, was expressed in Escherichia coli as a fusion protein bearing an N-terminal (His)6 purification tag. The expressed recombinant protein, rRBBI-8, is insoluble and accumulates as inclusion bodies. The insoluble protein was solubilized in 8 M urea under reducing environment and then refolded into its active conformation under optimized redox conditions. Strategies used to optimize yield and efficiency include selecting the redox system, increasing protein concentration during refolding by adding the denatured protein in a stepwise way, utilizing additives to prevent aggregation, and selecting buffer-exchanging conditions. A Ni-chelate affinity column was then employed to purify the renatured protein. rRBBI-8 shows strong inhibitory activity against trypsin and it can slightly inhibit chymotrypsin. In this study, a refolding and purification system was set up for this cysteine-rich recombinant protein expressed in a prokaryotic system.