Molecular characteristics and pathogenicity of a Tibet-origin mutant avian leukosis virus subgroup J isolated from Tibetan chickens in China.

Tibetan chicken is found in China Tibet (average altitude; ˃4500 m). However, little is known about avian leukosis virus subgroup J (ALV-J) found in Tibetan chickens. ALV-J is a typical alpharetrovirus that causes immunosuppression and myelocytomatosis and thus seriously affects the development of the poultry industry. In this study, Tibet-origin mutant ALV-J was isolated from Tibetan chickens and named RKZ-1-RKZ-5. A Myelocytomatosis outbreak occurred in a commercial Tibetan chicken farm in Shigatse of Rikaze, Tibet, China, in March 2022. About 20% of Tibetan chickens in the farm showed severe immunosuppression, and mortality increased to 5.6%. Histopathological examination showed typical myelocytomas in various tissues. Virus isolation and phylogenetic analysis demonstrated that ALV-J caused the disease. Gene-wide phylogenetic analysis showed the RKZ isolates were the original strains of the previously reported Tibetan isolates (TBC-J4 and TBC-J6) (identity; 94.5% to 94.9%). Furthermore, significant nucleotide mutations and deletions occurred in the hr1 and hr2 hypervariable regions of gp85 gene, 3'UTR, Y Box, and TATA Box of 3'LTR. Pathogenicity experiments demonstrated that the viral load, viremia, and viral shedding level were significantly higher in RKZ-1-infected chickens than in NX0101-infected chickens. Notably, RKZ-1 caused more severe cardiopulmonary damage in SPF chickens. These findings prove the origin of Tibet ALV-J and provide insights into the molecular characteristics and pathogenic ability of ALV-J in the plateau area. Therefore, this study may provide a basis for ALV-J prevention and eradication in Tibet.

Serum amyloid A regulates TLR2/4-mediated IFN-ß signaling pathway against Marek's disease virus.

Serum amyloid A (SAA), an acute response phase protein (APP), is crucial for the innate immune response during pathogenic microorganisms' invasion. Marek's disease virus (MDV) is a highly oncogenic alphaherpesvirus that activates multiple innate immune molecules, including SAA, in the host during infection. However, the pathway through which SAA participates in MDV-induced host innate immunity remains unknown. The present study aimed to elucidate the pathway through which SAA exerts its anti-MDV function. We observed that MDV infection in vivo and in vitro significantly elevated SAA expression. Furthermore, through SAA overexpression and knockdown experiments, we demonstrated that SAA could inhibit MDV replication. Subsequently, we found that SAA activated Toll-Like Receptor 2/4 (TLR2/4) -mediated Interferon Beta (IFN-ß) promoter activity and IFN regulatory factor 7 (IRF7) promoter activity. During MDV infection, SAA enhanced TLR2/4-mediated IFN-ß signal transduction and messenger RNAs (mRNAs) expression of type I IFN (IFN-I) and interferon-stimulated genes (ISGs). Finally, TLR2/4 inhibitor OxPAPC inhibits the anti-MDV activity of SAA. These results demonstrated that SAA inhibits MDV replication and enhancing TLR2/4-mediated IFN-ß signal transduction to promote IFNs and ISGs expression. This finding is the first to demonstrate the signaling pathway by which SAA exerts its anti-MDV function. It also provides new insights into the control of oncogenic herpesviruses from the perspective of acute response phase proteins.

Arsenic and cadmium bioavailability to rice (Oryza sativa L.) plant in paddy soil: Influence of sulfate application.

Arsenic (As) and cadmium (Cd) accumulate easily in rice grains that pose a non-negligible threat to human health worldwide. Sulfur fertilizer has been shown to affect the mobilization of As and Cd in paddy soil, but the effect of co-contamination by As and Cd has not been explored. This study selected three soils co-contaminated with As and Cd from Shangyu (SY), Tongling (TL) and Ma'anshan (MA). Incubation experiments and pot experiments were carried out to explore the effect of sulfate supply (100 mg kg-1) on the bioavailability of As and Cd in soil and the rice growth. The results showed that the exogenous sulfate decreased As concentrations in porewater of SY and TL by 51.1% and 29.2% through forming arsenic-sulfide minerals. The exchangeable Cd in soil also declined by 25.6% and 18.6% and transformed into Fe and Mn oxides-bound Cd. The relative abundance of Desulfotomaculum, Desulfurispora and dsr gene increased remarkably indicated that sulfate addition stimulated the activity of sulfate-reducing bacteria. In MA soil, sulfate addition immobilized Cd but had little effect on As solubility, which was speculated to be related to the high sulfate background of the soil. Further pot experiments showed that sulfate application significantly increased rice tillers, biomass, chlorophyll content in shoots, and decreased electrolyte leakage in root. Finally, sulfate significantly reduced As and Cd in SY rice shoots by 60.2% and 40.8%, respectively, while As decreased by 39.6% in TL rice shoots and Cd decreased by 23.0% in MA rice shoots. These results indicate that the application of sulfate can reduce the bioavailability of As and Cd in the soil-rice system and promote rice growth, and it is possible to reduce the accumulation of As and Cd in rice plants simultaneously.

Interaction of p10/p27 with macrophage migration inhibitory factor promotes avian leukosis virus subgroup J infection.

Avian leukosis virus subgroup J (ALV-J), an oncogenic retrovirus, induces myelocytoma and various other tumors in broilers and layers. Many recent studies have shown that ALV-J can hijack host molecules to facilitate infection. However, the molecular mechanisms of this process are not clear. Here, we aimed to elucidate the molecular mechanisms contributing to ALV-J infection. ALV-J hijacked MIF via p10 and p27 to facilitate ALV-J infection. ALV-J persistently activated MIF expression in DF-1 cells, and MIF significantly facilitated ALV-J internalization and replication, which demonstrated by MIF overexpression and knockdown experiments and treatment with the MIF antagonist ISO-1. Furthermore, we found that the two subunit proteins of Gag, p10 and p27, interacted with MIF in the cytoplasm, respectively. These results suggested that the p10 and p27 subunit in Gag protein recruited MIF to promote ALV-J infection, providing insights into the roles of the p10/p27 and the host factor MIF in ALV-J infection. The finding may facilitate the development of new strategies for controlling ALV-J or retrovirus infections.

Interaction between Avian Leukosis Virus Subgroup J Surface Protein and Doublecortin-Like Kinase 1 Accelerates Cell Proliferation and Epithelial-Mesenchymal Transition.

Avian leukosis virus subgroup J (ALV-J) induces myelocytomas, which can metastasize to multiple organs in diseased chickens. Although metastasis is the primary cause of death in such cases, the mechanism for it remains unclear. Here, we found that interaction between ALV-J surface protein (SU) and doublecortin-like kinase 1 (DCLK1) promotes epithelial-mesenchymal transition (EMT) and cell proliferation. We found that ALV-J can activate EMT in infected cells. Subsequently, proteomics analysis revealed that DCLK1, a well-established putative tumor stem cell marker, which is highly expressed in ALV-J-infected DF-1 cells and chickens, might be a potential factor mediating EMT. Furthermore, using immunofluorescence and immunoprecipitation, we verified that SU interacts with DCLK1. Functional studies suggested that overexpression of DCLK1 increased viral replication and promoted cell proliferation by accelerating the progression of cells from the G0/G1 phase to the S phase of cell cycle, whereas RNA interference of DCLK1 reduced viral replication and arrested cell proliferation by retarding cell cycle progression from the late G1 phase into the S phase in ALV-J-infected cells. Moreover, we demonstrate that the increased accumulation of DCLK1 promotes EMT by increasing the expression of N-cadherin, vimentin, MMP2, and transcription factor Snail1 and decreasing the expression of epithelial marker E-cadherin. These results suggest that ALV-J SU interacts with DCLK1, and accelerates cell proliferation, leading to increased viral replication and ultimately activating EMT, which paves the way for tumor metastasis. IMPORTANCE Tumor metastasis is a major challenge in cancer research, because of its systemic nature and the resistance of disseminated tumor cells to existing therapeutic agents. It is estimated that >90% of mortality from cancer is attributable to metastases. We found that ALV-J can activate EMT, which plays a critical role in cancer metastasis. Subsequently, we identified a tumor stem cell marker, DCLK1, in ALV-J infected cells, which interacts with surface protein (SU) of ALV-J to promote virus replication, activate EMT, and accelerate cell proliferation enabling ALV-J to obtain metastatic ability. Understanding the process of participation of ALV-J in EMT and the route of metastasis will help elucidate the mechanism of virus-induced tumor metastasis and help identify promising molecular targets and key obstacles for ALV-J control and clinical technology development.

[Effect of moxibustion on acupoints at "opening" time on telomere length and expression of liver cell cycle regulators in aging rats].

OBJECTIVE: To observe the effects of "lingguibafa" moxibustion performing at the appropriate acupoints at their "opening" time on telomere length，expressions of p53 of tumor supressor genes and retinoblastoma gene(Rb)in the liver of aging rats，so as to explore its mechanisms underlying delaying senescence. METHODS: Forty male SD rats were randomly divi-ded into normal, model, prevention and treatment groups, with 10 rats in each group. The rat model was established by intrape-ritoneally injection of D-galactose (200 mg/kg) once a day for 42 days. The rats in the prevention group were given "lingguibafa" moxibustion during modeling, while those in the treatment group were given "lingguibafa" moxibustion after modeling. Quantitative real-time PCR was used to detect the telomere length and the mRNA expressions of p53 and Rb，ELISA was used to detect the protein contents of p53 and Rb in the liver tissues. RESULTS: Compared with the normal group, the relative telomere length of the model group was significantly shortened (P<0.01), the mRNA expressions and protein contents of p53 and Rb were significantly increased (P<0.01). After intervention and in comparison with the model group, the relative telomere length of the prevention group and the treatments group were significantly increased (P<0.01), and the expressions of p53 and Rb mRNA and protein contents were significantly reduced (P<0.01, P<0.05). There were no significant difference between the prevention and the treatment groups in the abovementioned indexes (P>0.05). CONCLUSION: Moxibustion on acupoints at "opening" time can inhibit the shortening of telomere length and the down-regulation of the expressions of p53 and Rb in aging rats, which may contribute to its function in delaying the process of cell senescence.

Zinc oxide nanoparticles alleviate the arsenic toxicity and decrease the accumulation of arsenic in rice (Oryza sativa L.).

BACKGROUND: Rice is particularly effective, compared to other cereals, at accumulating arsenic (As), a nonthreshold, class 1 human carcinogen in shoot and grain. Nano-zinc oxide is gradually used in agricultural production due to its adsorption capacity and as a nutrient element. An experiment was performed to explore the effects of zinc oxide nanoparticles (nZnO) on arsenic (As) toxicity and bioaccumulation in rice. Rice seedlings were treated with different levels of nZnO (0, 10, 20, 50, 100 mg/L) and As (0, and 2 mg/L) for 7 days. RESULTS: The research showed that 2 mg/L of As treatment represented a stress condition, which was evidenced by phenotypic images, seedling dry weight, chlorophyll, and antioxidant enzyme activity of rice shoot. The addition of nZnO (10-100 mg/L) enhanced the growth and photosynthesis of rice seedlings. As concentrations in the shoots and roots were decreased by a maximum of 40.7 and 31.6% compared to the control, respectively. Arsenite [As (III)] was the main species in both roots (98.5-99.5%) and shoots (95.0-99.6%) when exposed to different treatments. Phytochelatins (PCs) content up-regulated in the roots induced more As (III)-PC to be complexed and reduced As (III) mobility for transport to shoots by nZnO addition. CONCLUSION: The results confirmed that nZnO could improve rice growth and decrease As accumulation in shoots, and it performs best at a concentration of 100 mg/L.

Effect of orthodontic force on inflammatory periodontal tissue remodeling and expression of IL-6 and IL-8 in rats.

OBJECTIVE: To investigate effect of orthodontic force on inflammatory periodontal tissue remodeling and expression of IL-6 and IL-8 in rats. METHODS: Eighty SD rats were randomly divided into 4 groups, blank control group (group A) with 5 rats, treatment normal group (group B) with 25 rats, inflammation control group (group (group C) with 25 rats, inflammation treatment group (group D) with 25 rats. Immunohistochemistry and histomorphometric analysis was performed to measure the expression of IL-6, IL-8 and the first molar to the recent movement in the distance. RESULTS: The expression of IL-8 reached a maximum on day 5 and declined thereafter in group B; the expression of IL-6 reached a maximum on day 5 in group B. The expression of IL-6 and IL-8 was gradually weakened with time in group C. The expression of IL-6 and IL-8 were high, and reached a maximum on day 5 and declined thereafter in group D. AD of positive cells in group D were higher than group B at each time point (P<0.05). The time which 0.49 N orthodontic force was loaded was longer, orthodontic tooth movement distance was greater. Movement distance in group D were longer than group B (P<0.05). CONCLUSIONS: Orthodontic force as well as inflammatory stimulus can evoke the expression of IL-6 and IL-8. Under the combined effects of inflammation and orthodontic force, the expression of IL-6, IL-8 will increase.

[Estimating genetic distance and phylogenetic tree of HPA-1-3, 5, and 15 in different populations].

According to the human platelet alloantigens (HPA) polymorphisms in five systems, the distributions of HPA-1 -3, 5, and 15 systems in 1 000 Chinese donors were carried out by using a polymerase chain reaction with sequence-specific primers (PCR-SSP) method. The genetic distance and phylogenetic tree between Chinese Hans and other populations were estimated by using DISPAN and PHYLIP software. As presented by the phylogenetic tree, Asian had a convergence with European first, and grouped together with African. Beninese which came from Africa was on the top of dendrogram. Indian was located between Asian and European. Brazilian was converged with other Europe populations. Oceanian Polynexiya had been shown specifically to cluster with Asia populations. These results proved the "out of Africa theory" from one side, and it also confirmed that early migration of Asian is from south to southeast, and east Asia., thus it is probable that Europeans are migrated from south to north, and west Europe. As genetic distance was estimated effectively by HPA systems, HPA systems could serve as the genetic marker in human migration and evolution research.

HLA-A, -B, -DR haplotype frequencies from DNA typing data of 26,266 Chinese bone marrow donors.

HLA phenotypes of 26,266 Chinese individuals who were recruited as potential hematopoietic stem cell donors by the Shanghai Red Cross Marrow Donor Registry, part of the China Marrow Donor Program, were determined for HLA-A, -B, and -DRB1 alleles at low to intermediate resolution using DNA-based typing methods. The large sample size of the study allowed accurate calculation of the Chinese HLA haplotype frequencies. The observed alleles correspond to 19 HLA-A, 44 -B, and 13 -DR split antigens. The serologic equivalents of HLA-A36, -A80, -B78, and -DR18 alleles were not observed. A total of 2,241 distinct HLA-A, -B, -DRB1 haplotypes were identified. Three-locus haplotype frequency was estimated using the maximum likelihood method. The lowest haplotype frequency that can be reliably estimated at a 95% confidence level was 0.000057. Using this cutoff value, 1,220 haplotypes (54%) were statistically reliable and their cumulative haplotype frequency was 0.9730. The cumulative haplotype frequency of the remaining 1,021 haplotypes (46%) was 0.0270. A regression equation of p = 0.192 log N - 0.576 was derived to estimate the probability (p) of finding an HLA-A, -B, -DR split antigens-matched donor in a pool of N Chinese donors.