HLA-DQB1 Allele Polymorphism Associated with Oral Submucous Fibrosis in Hunan, China.

Methods: 44 OSF patients and 44 healthy volunteers were included in this study. To detect the expression frequency of HLA-DQB1 alleles in the two groups and analyze significant allelic subtypes and their relative risk, polymerase chain reaction (PCR) sequence-specific primers were used. Subsequently, based on the identification of differential genes, we compare the gene expression levels of OSF patients and healthy volunteers expressing differential genes by real-time quantitative PCR. Results: The expression frequency of the HLA-DQB1 ∗05 : 02 allele in the OSF group (36.4%) was significantly higher than in the controls (13.6%), and exposure to the HLA-DQB1 ∗05 : 02 allele was strongly related to OSF (OR (95% CI) = 3.619 (1.257,10.421), Wald χ2 = 5.681, P=0.017). However, there were no significant differences in the allele expression frequencies of DQB1 ∗02 : 01, DQB1 ∗03 : 03, DQB1 ∗05 : 01, DQB1 ∗05 : 03, DQB1 ∗06 : 02, DQB1 ∗06 : 03, and DQB1 ∗06 : 04 in the OSF group compared with the controls (all P > 0.05). Furthermore, the relative expression level of the HLA-DQB1 ∗05 : 02 allele in the OSF group (3.98 ± 3.50) was significantly higher than in controls (0.70 ± 0.41). Conclusions: There are differences in the HLA-DQB1 allele polymorphisms between the healthy population and patients with oral submucosal fibrosis. Preliminarily, it is suggested that the HLA-DQB1 ∗05 : 02 allele, which has a strong correlation with OSF and great differential expression between patients with OSF and controls, might be a susceptibility gene for OSF in Hunan.

Positive responses and mechanisms of nitrifying sludge to carbon quantum dots: reactor performance, microbial behavior, and antioxidant defense.

Extensive application of carbon quantum dots (CQDs) enlarges its concentration in sewage treatment system. The response of nitrifying sludge to CQDs after long-term exposure was investigated. Results showed that CQD concentrations of 0-100 mg/L presented positive effect to enzymes involved in nitrification, accelerating NH4+-N degradation and NO2--N transformation. The oxidation rate of NO2--N was significantly improved from 3.14 to 7.91 mg/(L h) under the stress of 100 mg/L CQDs. Besides, CQDs stimulated the production of sludge biomass and kept the stability of sludge settleability. Additionally, CQDs were mainly captured by loosely bound extracellular polymeric substances, reducing aromatic-like protein. Microbes alleviated CQD stress by secreting tryptophan-like protein and polysaccharides. After few CQDs entered cells, intracellular antioxidant defense was activated. Total antioxidant capacity level was heightened at least 31%. The activities of superoxide dismutase and catalase were enhanced at relatively low and high CQD concentration levels. Hence, microbial metabolic pathways, microbial community, and nitrifying bacteria were not significantly affected by CQDs. The findings of this work provide new insight for understanding the environmental implication of CQDs in the biological treatment system.

The ecotoxicological effects of chromium (III) oxide nanoparticles to Chlorella sp.: perspective from the physiological and transcriptional responses.

Extensive application of nanomaterials enlarges its concentrations in the aquatic environments and poses a threat to algae. This study comprehensively analyzed the physiological and transcriptional responses of Chlorella sp. after being exposed to chromium (III) oxide nanoparticles (nCr2O3). The nCr2O3 at 0-100 mg/L presented adverse effects on cell growth (96 h EC50 = 16.3 mg/L), decreasing the photosynthetic pigment concentrations and photosynthetic activity. Moreover, more extracellular polymeric substances (EPS), especially polysaccharides in soluble EPS, were produced in algae cell, which mitigated the damage of nCr2O3 to cells. However, with the increase of nCr2O3 doses, the EPS protective responses were exhausted, accompanied by toxicity in the form of organelle damage and metabolic disturbance. The enhanced acute toxicity was closely related to the physical contact of nCr2O3 with cells, oxidative stress, and genotoxicity. Firstly, large amounts of nCr2O3 aggregated around and were attached to cells, causing physical damage. Then, the intracellular reactive oxygen species and malondialdehyde levels were significantly increased that led to lipid peroxidation, especially at 50-100 mg/L nCr2O3. Finally, the transcriptomic analysis further revealed that the transcription of ribosome, glutamine, and thiamine metabolism-related genes were impaired under 20 mg/L nCr2O3, suggesting nCr2O3 inhibited algal cell growth through metabolism, cell defense, and repair, etc.

The nutrient removal and tolerance mechanism of a heterotrophic nitrifying bacterium Pseudomonas putida strain NP5 under metal oxide nanoparticles stress.

The occurrence of metal oxide nanoparticles (NPs) in wastewater treatment plants (WWTPs) has raised great concerns about their adverse impacts on nitrification performance. In this study, a heterotrophic nitrifying bacterium Pseudomonas putida strain NP5 showed strong resistance against TiO2 and NiO NPs. Under 5-50 mg/L NP stress, cell viability was still normal, and the final nutrient removal rates, always higher than 80%, were slightly inhibited. Correspondingly, the PO43--P removal rates were almost the same as those observed in the control test. Although the enzyme assay demonstrated ammonia monooxygenase and hydroxylamine oxidoreductase activities markedly decreased caused by increased reactive oxygen species (ROS) level under 50 mg/L NPs stress. The total antioxidant capability of NP5 could eliminate excess ROS to maintain a balance between oxidants and antioxidants. Besides, in response to the escalating burden of NPs, strain NP5 tended to secrete more extracellular polymeric substances (EPS), which could protect cell from being damaged by binding to ions and coating. Thus, the strong NP resistance of NP5 would help to overcome the vulnerability of the nitrification process in WWTPs.

[Denitrification Process and N2O Production Characteristics of Heterotrophic Nitrifying Bacterium Pseudomonas aeruginosa YL].

Because of the massive discharge of nitrogenous wastewater, the eutrophication of a water body is becoming increasingly serious, and how to effectively remove nitrogen from this wastewater remains an urgent problem to be solved. In this study, due to disadvantages in the traditional biological nitrogen removal process, such as complex and long procedures, high energy consumption, weak impact resistance, and N2O release, the nitrogen removal theory by heterotrophic nitrification was further analyzed by discussing the physiological-biochemical, heterotrophic nitrification-aerobic denitrification, and N2O production characteristics of a high-efficiency heterotrophic nitrifying bacteria Pseudomonas aeruginosa YL. Results show that the strain YL had an eminent heterotrophic nitrification and aerobic denitrification ability, and NH4+-N, NO2--N, and NO3--N with concentration of 100 mg·L-1 could be completely removed during the 24-hour incubation period. There was almost no intermediate product in the process of heterotrophic nitrification, however when NO3--N was used as nitrogen source, the accumulation of NO2--N reached 25.55 mg·L-1. Meanwhile, the successful expression of denitrification genes napA, nirK, and nosZ further confirmed the aerobic denitrification ability of strain YL. Gaseous nitrogen products accounted for about 30%-40% of removed TN in the heterotrophic nitrification-aerobic denitrification process by strain YL, and N2 was the main denitrification product. When NH4+-N, NO2--N, and NO3--N were used as the sole nitrogen source, N2 production amounted to 3.46, 3.49, and 3.36 mg, respectively. In contrast, only small amounts of N2O were produced in the denitrification process by strain YL, and the total amount was 6.63 µg when NH4+-N was the nitrogen source, which was much lower than in the cases of NO2--N and NO3--N as the sole nitrogen source. In addition, high C/N, low pH, high temperature, high NH4+-N, and high NO2--N conditions could result in more N2O generation. Nevertheless, most environmental factors had little effect on N2O production of strain YL, and the maximum N2O production was significantly lower than that of short-cut nitrification system and autotrophic nitrification system. These results demonstrated that strain YL exhibited excellent abilities of nitrogen removal, N2O emission control, and tolerance to environmental conditions, and could be an effective candidate for treating wastewater without secondary air pollution.

[Simultaneous Nitrogen and Phosphorus Removal and Kinetics by the Heterotrophic Nitrifying Bacterium Acinetobacter junii NP1].

Due to the problems of traditional biological nitrogen and phosphorus removal, including long process duration and high infrastructural and operational costs, the simultaneous nitrogen and phosphorus removal capabilities, influencing factors and kinetic characteristics were systematically studied using the heterotrophic nitrifier Acinetobacter junii NP1 which possesses efficient simultaneous nitrogen and phosphorus removal ability. The results showed that strain NP1 exhibited efficient heterotrophic nitrification ability with a maximum ammonia removal rate of 99.12%. Furthermore, only small amounts of nitrification intermediates were accumulated during the reaction process. Strain NP1 also adapted well to higher ammonia nitrogen loading. In addition, strain NP1 had efficient aerobic denitrification characteristics, and could utilize nitrite and nitrate for growth and metabolism, achieving a maximum removal rate of 91.40% and 95.10%, respectively. The heterotrophic nitrification process of strain NP1 was accompanied by simultaneous phosphorus accumulation, and the appropriate ratio of nitrogen to phosphorus was beneficial for the simultaneous removal of nitrogen and phosphorus. When the ratio of nitrogen to phosphorus was 5:1, the maximum ammonia nitrogen and phosphate removal rates reached 99.21% and 88.35%, respectively. The bacterial growth process of stain NP1 matched the Logistic model (R2>0.99), and the nitrogen and phosphate degradation conformed to the Compertz model (R2>0.99). The maximum conversion rates of nitrogen and phosphate (Rm) obtained by model fitting were in the order ammonia>nitrate>nitrite, and lag time (t0) was in the order nitrate>nitrite>ammonia. According to the analysis of the degradation kinetics of the matrix and the removal rate of nitrogen and phosphorus, the optimal conditions were found to be sodium succinate, C/N=10, T=30℃, and r=160 r·min-1.

Simultaneous removal of nitrogen and phosphorous by heterotrophic nitrification-aerobic denitrification of a metal resistant bacterium Pseudomonas putida strain NP5.

A novel strain NP5 with efficient heterotrophic nitrification, aerobic denitrification and phosphorus accumulation ability was isolated and identified as Pseudomonas putida strain NP5. The removed ammonium and phosphate were mainly converted into intracellular components by assimilation, and negligible nitrification intermediates and N2O were accumulated during heterotrophic nitrification. In addition, the optimal conditions for nutrient removal were: succinate as carbon source, C/N 10, P/N 0.2, temperature 30 °C, salinity 0% and shaking speed 160 rpm. Besides, strain NP5 possessed an exceptional heavy metal and nanoparticles resistance. Cr6+ was found to be the most toxic among the tested metals, and it could be removed simultaneously. Moreover, an obvious phosphorus release was observed under anaerobic condition, and repeated exposure to the anaerobic/aerobic conditions could significantly improve the nutrient removal. Furthermore, the successful expression of key enzymes for nitrogen and phosphorous removal provided additional evidence for possibility of simultaneous nitrification, denitrification and phosphorus removal.

[Correlation research on the expression of FcgammaR II b on B cells and rheumatoid arthritis patients of Shen deficiency syndrome].

OBJECTIVE: To study the correlation between the expression of Fcgamma receptor II b (FcgammaRII b) on B cells and rheumatoid arthritis (RA) patients of Shen deficiency syndrome (SDS). METHODS: There were 43 RA patients, including 26 of SDS and 17 of non-SDS. The expression levels of FcgammaRII b on naive B cells, memory B cells, and plasma blasts in the peripheral blood were detected by flow cytometry. The numbers of tender joints, numbers of swollen joints, erythrocyte sedimentation rate (ESR), rheumatoid factor (RF), and disease activity score (DAS28), the correlation between the distribution of B cells and the expression level of FcgammaRII b in RA patients were analyzed. Besides, another 21 healthy volunteers were recruited as the control group. RESULTS: The expression level of FcgammaRII b was 49.65% +/- 15.86% on memory B cells and 43.69% +/- 22.57% on plasma blasts in RA patients of SDS, significantly down-regulated when compared with those of the control group (64.03% +/- 6.01%, 66.59% +/- 10.18%, P < 0.01). The expression level of FcgammaRII b on memory B cells of RA patients of non-SDS was down-regulated more obviously when compared with that of the control group (52.70% +/- 9.52% versus 64.03% +/- 6.01%, P < 0.01). The expression level of FcgammaRII b on plasma blasts was obviously lower in RA patients of SDS than in RA patients of non-SDS (56.10% +/- 17.05%, P < 0.05). The expression level of FcgammaRII b on memory B cells was not correlated with numbers of tender joints, numbers of swollen joints, ESR, RF, or DAS28. CONCLUSIONS: The defective immunological tolerance of B cells in RA patients of SDS might be closely correlated with down-regulation of FcgammaRII b on memory B cells and plasma blasts. There might exist genetic abnormality of FcgammaRII b gene in RA patients of SDS, thus inducing loss of autoimmunity tolerance.

[Correlation study of auto-immune antibodies and rheumatoid arthritis patients of Shen deficiency syndrome].

OBJECTIVE: To investigate the correlation between auto-immune antibodies and rheumatoid arthritis (RA) patients of Shen deficiency syndrome (SDS), thus providing clinical evidence for further researches on molecular biological mechanisms of RA patients of SDS. METHODS: Totally 451 RA patients were assigned to the SDS group and the non-SDS group. Their general conditions (including gender, age, duration, and age of onset), C reactive protein (CRP), erythrocyte sedimentation rate (ESR), platelet (PLT), disease activities (DAS28), auto-antibodies [rheumatoid factor (RF), anti-CCP antibodies, anti-nuclear antibody (ANA)] were compared between the two groups. RESULTS: (1) The scores for EST, PLT, and DAS28 were obviously higher in the SDS group than in the non-SDS group (P < 0.05, P <0. 01). (2) The level of average RF was (697.32 +/-1 061.38 IU/mL) in the SDS group, higher than that in the non-SDS group (439.91 +/- 672.24 IU/mL, P <0.01). There was no statistical difference in anti-CCP antibody between the two groups (P >0.05).(3) The ANA positive rate of RA patients was 29. 63% (120/405). It was 37.19% (74/199) in RA patients of SDS and 22. 33% (46/206) in RA patients of non-SDS, showing statistical difference between the two groups (P <0.01). (4) The odds ratio for high level RF positive and ANA positive was 1. 574 and 2. 059 folds in RA patients of SDS as high as that in RA patients of non-SDS. CONCLUSIONS: RA patients of SDS would have higher risk of having auto-immune antibodies, fastened development, more worsen joint damage, and more poor prognosis. Its mechanisms might be closely associated with autoimmune tolerance.

[Pharmacological mechanisms of ethyl acetate extraction of Tongbiheji for active T cell signaling molecules].

AIM: To confirm extracts of activity from Traditional Chinese Medicine TongBiHeJi, study effect on two signaling pathways of T cells and clarify the pharmacological mechanisms of TongBiHeJi. METHODS: Concanavalin(ConA) were added successively into rats lymphocytic culture with different extracts of activity from Traditional Chinese Medicine. After 24 hours, CD71 expression rate on rat T lymphocytes activated with ConA was analyzed by flow cytometry. TCR, CD28 and ICOS on T cells were detected after T lymphocytes of rat activated by ConA were cultivated with various EthylAcetate extraction of TongBiHeJi(TBHJ) and Methotrexate (MTX) for 48 hours. RESULTS: CD71 expression rate on rat T lymphocytes induced by ConA was increased to 69.7%. TBHJ inhibited the rate of CD3(+);CD71(+); expression(32.5%); ConA up-regulated TCR, CD28 and ICOS expression on T cells obviously. There was different between ConA and positive control significantly(P<0.001). TBHJ could down-regulate obviously TCR, CD28 and ICOS expression on ConA-activated T lymphocytes with Concentration-dependent, especially ICOS. MTX inhibited CD3(+);CD71(+); and CD3(+);TCR(+); expression also. CONCLUSION: TBHJ inhibited T cells activation by adjusting two signaling pathways. That implied TBHJ could block CD28-ICOS signaling molecules to induce immunological tolerance. This study provided an experimental basis for application of TongBiHeJi to treatment of rheumatoid arthritis.