Effects of centrifugation prior to pneumatic tube system transport on routine biochemical and immunological tests of susceptibility to hemolysis.

BACKGROUND: Pneumatic tube system (PTS) may be associated with preanalytical hemolysis. The objective of this study was to evaluate the effects of PTS on biochemical and immunological tests susceptible to hemolysis and try to find ways to reduce the result bias caused by PTS. METHODS: Laboratory parameters were compared between PTS without centrifuging group, PTS after centrifuging group, PTS with serum group, and hand-delivered (HD) group. Studies were performed to access the influence of different PTS transport frequencies on laboratory assays. RESULTS: PTS transportation resulted in obviously increase in LDH (lactate dehydrogenase) and NSE (neuron-specific enolase) results (LDH: Bias = 17.95%, 95% confidence interval (CI) = -3.13-39.02; p < 0.001; NSE: Bias = 64.26%, 95% CI = -21.29-149.82; p < 0.001; respectively). After pre-centrifugation, no statistical difference was observed in LDH results (Bias = 2.83%, 95% CI = -13.00-18.65; p = 0.737). However, the bias of NSE still reach 19.16% (95% CI = -41.78-80.11), which exceeded the clinical acceptable range (p = 0.017). Both LDH(p = 0.931) and NSE(p > 0.999) show no statistical difference between PTS with serum group and HD group (LDH: Bias = -1.60%, 95% CI = -6.00-2.81; NSE: Bias = -3.68%, 95% CI = -11.35-3.99). CONCLUSION: PTS can lead to falsely increased LDH and NSE test results. Only loading the centrifuged upper serum in new tubes during PTS transport can eliminate the results bias of NSE.

Neoadjuvant Immunotherapy Combined with Chemotherapy for Local Advanced Non-Small-Cell Lung Cancer in a Patient with a History of Breast Cancer: A Case Report.

Durvalumab consolidation therapy is the standard treatment after concurrent chemoradiotherapy for patients with surgically unresectable stage IIIA (N2) non-small-cell lung cancer (NSCLC). Neoadjuvant therapy followed by surgery could reduce locoregional and distant recurrence and improve the survival rate for surgically resectable NSCLC. However, the value of neoadjuvant therapy in locally advanced potentially resectable NSCLC remains controversial. Herein, we report a locally advanced potentially resectable NSCLC case with a history of breast cancer who achieved a pathologic complete response (pCR) after preoperative treatment with pembrolizumab and chemotherapy. A 50-year-old woman developed squamous cell carcinoma (SCC) (left lower lobe of the lung, stage IIIA-N2) after two years of chemotherapy and anti-HER2 therapy following a diagnosis of HER2-overexpressing breast cancer. Surgical resection was attempted despite an MDT classification as unamenable to curative surgical resection. After two cycles of neoadjuvant chemotherapy combined with anti-PD1 immunotherapy, the tumor significantly shrank, then the patient underwent a left lower lobectomy. Complete resection with negative margins (R0 resection) was achieved in the patient. The patient experienced grade 1-2 adverse effects and no grade 3 or worse adverse effects occurred. Cardiotoxicity did not occur in the patient despite prior anti-HER2 treatment for breast cancer. Our case study contributes to the existing evidence on the feasibility, efficacy, and safety of neoadjuvant immunotherapy combined with chemotherapy in locally advanced unresectable NSCLC. Furthermore, future studies are needed to determine which patients can benefit from immunoadjuvant therapy and the duration and course of preoperative and postoperative immunotherapy.

Construction and validation of a prognostic model for kidney renal clear cell carcinoma based on podocyte-associated genes.

BACKGROUND: As the most common renal malignancy, kidney renal clear cell carcinoma (KIRC) has a high prevalence and death rate as well as a poor response to treatment. Developing an efficient prognostic model is essential for accurately predicting the outcome and therapeutic benefit of KIRC patients. METHODS: Gene expression profiles of podocyte-associated genes (PAGs) were obtained from The Cancer Genome Atlas and GEO datasets. Cox regression and Lasso regression analyses were then used for filtering prognosis-associated PAGs. Risk score (RS) was computed from these genetic characteristics. Kaplan-Meier analysis and receiver operating characteristic (ROC) curves were applied for ascertaining the prognostic value. Stratified analysis was used to sufficiently validate model performance. Concordance index was used to compare the predictive ability of different models. Immuno-infiltration analysis and immunophenoscore were utilized for the prediction of patient reaction to immune checkpoint inhibitors (ICIs). RESULTS: WT1, ANLN, CUBN, OSGEP, and RHOA were significantly associated with KIRC prognosis. Prognostic analysis indicated that high-RS patients have a significantly poorer outcome. Cox regression analysis demonstrated a potential for RS to be an independent prognostic factor. Pathway enrichment results indicated a lower enrichment of cancer-related biological pathways in the low-RS subgroup. Immune infiltration analysis and IPS demonstrated greater responsiveness to ICIs in the high RS group. CONCLUSIONS: This podocyte-associated KIRC prognostic model can effectively predict KIRC prognosis and immunotherapy response, which may help to provide clinicians with more effective treatment strategies.

Identification of IRF-associated molecular subtypes in clear cell renal cell carcinoma to characterize immunological characteristics and guide therapy.

Background: Recently studies have identified a critical role for interferon regulatory factor (IRF) in modulating tumour immune microenvironment (TME) infiltration and tumorigenesis. Methods: Based on IRF1-9 expression profiles, we classified all ccRCC samples into three molecular subtypes (clusters A-C) and characterized the prognosis and immune infiltration of these clusters. IRFscore constructed by principal component analysis was performed to quantify IRF-related subtypes in individual patients. Results: We proved that IRFscore predicted multiple patient characteristics, with high IRFscore group having poorer prognosis, suppressed TME, increased T-cell exhaustion, increased TMB and greater sensitivity to anti- PD-1/CTLA-4 therapies. Furthermore, analysis of metastatic ccRCC (mccRCC) molecular subtypes and drug sensitivity proved that low IRFscore was more sensitive to targeted therapies. Moreover, IRFscore grouping can be well matched to the immunological and molecular typing of ccRCC. qRT-PCR showed differential expression of IRFs in different cell lines. Conclusions: Evaluating IRF-related molecular subtypes in individual ccRCC patients not only facilitates our understanding of tumour immune infiltration, but also provides more effective clinical ideas for personalised treatment.

Hepatitis D: challenges in the estimation of true prevalence and laboratory diagnosis.

Hepatitis delta virus (HDV) is a defective single negative chain RNA virus, as its envelope protein synthesis is dependent on hepatitis B virus (HBV). Studies have consistently shown that coinfection of HBV and HDV is the most serious form of viral hepatitis, with accelerated progression to liver cirrhosis and hepatocellular carcinoma. About 74 million of HBV surface antigen (HBsAg) positive patients worldwide are also co-infected with HDV. Besides, patients with intravenous drug use and high-risk sexual behavior are at higher risk of HDV infection. Therapeutic schedules for HDV are limited, and relapse of HDV has been observed after treatment with pegylated interferon alpha. To reduce the transmission of HDV, all people infected with HBV should be screened for HDV. At present, several serological and molecular detection methods are widely used in the diagnosis of HDV. However, due to the lack of international standards diagnostic results from different laboratories are often not comparable. Therefore, the true prevalence of HDV is still unclear. In this manuscript, we have analyzed various factors influencing the estimation of HDV prevalence. We have also discussed about the advantages and disadvantages of currently available HDV laboratory diagnostic methods, in order to provide some ideas for improving the detection of HDV.

Association of Serum Neuron-Specific Enolase and C-Reactive Protein With Disease Location and Endoscopic Inflammation Degree in Patients With Crohn's Disease.

Objective: The objective of this study was to explore the association between serum markers neuron-specific enolase (NSE) and C-reactive protein (CRP) with intestinal lesion location and degree of inflammation in patients with Crohn's disease (CD). Design: The levels of serum NSE, CRP, and fecal calprotectin (FC) in patients with CD were analyzed retrospectively. The severity of inflammatory lesions in the intestinal wall was accessed using the Simple Endoscopic Score for Crohn's disease (SES-CD). Results: The levels of NSE in patients with CD were higher than those of healthy individuals (14.87 vs. 12.68 ng/ml, P < 0.001). The levels of CRP in patients with CD were higher than those of healthy individuals (12.30 vs. 3.40 mg/l, P < 0.001). The FC levels in patients with CD were higher than those of patients with non-inflammatory bowel disease (1,143.90 vs. 114.21 µg/g, P < 0.05). The levels of NSE in CD with ileal lesions and simultaneous ileal and colon lesions were significantly higher than those in patients with CD with colonic lesions. However, the CRP was higher in patients with colonic lesions than those with ileal lesions. The levels of NSE in patients with severe inflammation were higher than those in patients with moderate inflammation (15.95 vs. 13.89 ng/ml, P < 0.05). Similarly, the NSE levels in patients with CD with severe inflammation were higher than those in patients with CD with mild inflammation (15.95 vs. 13.53 ng/mL, P < 0.05). The levels of CRP in severe inflammation were higher than those in moderate inflammation (29.80 vs. 19.60 mg/l, P < 0.05). In addition, the CRP levels in severe inflammation were higher than those in mild inflammation (29.80 vs. 5.86 mg/l, P < 0.05). ROC curve analysis showed that when NSE was combined with CRP for distinguishing between patients with CD and those without CD, sensitivity increased to 80.41%, specificity increased to 74.66%, and a highest AUC was equal to 0.843. Conclusion: Our study shows that serum NSE and CRP can be used to assess the severity of CD as well as the location of intestinal involvement. Therefore, NSE and CRP could be used as the non-invasive tests in detecting the location and severity of disease in patients with CD in daily routine practice.

STING and liver disease.

STING (stimulator of interferon genes) also known as transmembrane protein 173 (TMEM173) is a cytoplasmic DNA sensor which can be activated by the upstream cyclic dinucleotides (CDNs). This activation produces cytokines such as interferons and pro-inflammatory factors via the downstream IRF3 and NF-κB pathways, triggering an innate immune response and adaptive immunity to maintain homeostasis. STING is mainly expressed and activated in non-parenchymal cells, thus exerting a corresponding effect to maintain the homeostasis of the liver. In viral hepatitis, interferons and pro-inflammatory factors produced after STING activation initiate the immune response to inhibit virus replication and assembly. In the case of metabolic diseases of the liver, the activation of STING in kupffer cells and hepatic stellate cells leads to inflammation, the proliferation of connective tissue, and metabolic disorders in the hepatocytes, promoting the occurrence and development of the disease. In hepatocellular carcinoma, STING has two contradictory roles. When STING is activated in dendritic cells and macrophages, a large number of cytokines can be produced to initiate innate immune effects directly and to exert adaptive immunity through the recruitment and activation of T cells; however, aberrant activation of the STING pathway leads to a weakening of immune function and promotes oncogenesis and metastasis. Here, we summarize the interactions between STING and liver disease that have currently been identified and how to achieve therapeutic goals by modulating the activity of the STING pathway.

Association of Rotavirus Vaccines With Reduction in Rotavirus Gastroenteritis in Children Younger Than 5 Years: A Systematic Review and Meta-analysis of Randomized Clinical Trials and Observational Studies.

Importance: Rotavirus vaccines have been introduced worldwide, and the clinical association of different rotavirus vaccines with reduction in rotavirus gastroenteritis (RVGE) after introduction are noteworthy. Objective: To evaluate the comparative benefit, risk, and immunogenicity of different rotavirus vaccines by synthesizing randomized clinical trials (RCTs) and observational studies. Data Sources: Relevant studies published in 4 databases: Embase, PubMed, the Cochrane Library, and Web of Science were searched until July 1, 2020, using search terms including "rotavirus" and "vaccin*." Study Selection: Randomized clinical trials and cohort and case-control studies involving more than 100 children younger than 5 years that reported the effectiveness, safety, or immunogenicity of rotavirus vaccines were included. Data Extraction and Synthesis: A random-effects model was used to calculate relative risks (RRs), odds ratios (ORs), risk differences, and 95% CIs. Adjusted indirect treatment comparison was performed to assess the differences in the protection of Rotarix and RotaTeq. Main Outcomes and Measures: The primary outcomes were RVGE, severe RVGE, and RVGE hospitalization. Safety-associated outcomes involved serious adverse events, intussusception, and mortality. Results: A meta-analysis of 20 RCTs and 38 case-control studies revealed that Rotarix (RV1) significantly reduced RVGE (RR, 0.316 [95% CI, 0.224-0.345]) and RVGE hospitalization risk (OR, 0.347 [95% CI, 0.279-0.432]) among children fully vaccinated; RotaTeq (RV5) had similar outcomes (RVGE: RR, 0.350 [95% CI, 0.275-0.445]; RVGE hospitalization risk: OR, 0.272 [95% CI, 0.197-0.376]). Rotavirus vaccines also demonstrated higher protection against severe RVGE. Additionally, no significant differences in the protection of RV1 and RV5 against rotavirus disease were noted in adjusted indirect comparisons. Moderate associations were found between reduced RVGE risk and Rotavac (RR, 0.664 [95% CI, 0.548-0.804]), Rotasiil (RR, 0.705 [95% CI, 0.605-0.821]), and Lanzhou lamb rotavirus vaccine (RR, 0.407 [95% CI, 0.332-0.499]). All rotavirus vaccines demonstrated no risk of serious adverse events. A positive correlation was also found between immunogenicity and vaccine protection (eg, association of RVGE with RV1: coefficient, -1.599; adjusted R2, 99.7%). Conclusions and Relevance: The high protection and low risk of serious adverse events for rotavirus vaccines in children who were fully vaccinated emphasized the importance of worldwide introduction of rotavirus vaccination. Similar protection provided by Rotarix and RotaTeq relieves the pressure of vaccines selection for health care authorities.

Surface Plasmon-Enhanced Luminescence of CdSe/CdS Quantum Dots Film Based on Au Nanoshell Arrays.

In this paper, Au nanoshell arrays, serving as a photo-activated material, are fabricated via the combination of self-assembled nanosphere lithography and the thermal decomposing polymer method. The intensity and position of surface plasmonic resonance can be tuned from the visible region to the near-infrared region by changing the size of Au nanoshell arrays. When resonance absorption peaks of metal nanoparticles are matched with emission wavelengths of core-shell CdSe/CdS quantum dots, fluorescent intensity of CdSe/CdS quantum dots can be strongly enhanced. The physical mechanism of fluorescent enhancement is explained.

Higher risk of myocardial injury in chest pain patients with elevated red blood cell distribution width.

BACKGROUND: High level of red blood cell distribution width (RDW) has been associated with adverse outcomes in coronary artery disease patients. We aimed to investigate the relationship between RDW and the risk of myocardial injury in chest pain patients. METHODS AND RESULTS: We retrospectively reviewed 2078 chest pain patients with suspected acute myocardial infarction. Myocardial injury was defined as high-sensitivity cardiac troponin T (hs-cTnT) >14 ng/L. RDW was associated with hs-cTnT (r = 0.607) and the risk of myocardial injury stepwise increased across increasing RDW quartiles in all subgroups based on age and sex. The receiver operating characteristic curve analysis was calculated to assess the elevated RDW to predict myocardial injury, with the cutoff value of 13.25%. RDW had a high sensitivity (78.10%), specificity (87.44%), as well as positive predictive value (77.48%). The area under the curve (AUC) for all patients was 0.88 (95%CI 0.87, 0.90) and there is no statistical significant in AUCs for all subgroups. CONCLUSIONS: Elevated RDW was significantly associated with a higher risk of myocardial injury in chest pain patients with potential acute myocardial infarction. The RDW may be helpful to identify myocardial injury in such patients.

Sulfur rich microporous polymer enables rapid and efficient removal of mercury(II) from water.

Design and synthesis of adsorbents for efficient decontamination of hazardous contaminants Hg2+ from wastewater, based on a facile and economical strategy, is an attractive target. Here, a novel sulfur rich microporous polymer (sulfur content of 31.4 wt %) with high surface area as well as densely populated sulfur atom with fast accessibility was reported to remove mercury (II) from water. The as prepared polymer (SMP) exhibited high binding affinity, high adsorption capacities, rapid adsorption kinetics, and good recyclability for Hg2+. The adsorption capacity of SMP was 595.2 mg g-1. Furthermore, SMP could reduce trace concentrations of Hg2+ from 200 p. p. b. to a level below drinking water standards (2 p. p. b.) within 3 min. This work allows large-scale production of sulfur rich porous materials for the practical application in water treatment.

Methyllithium-Doped Naphthyl-Containing Conjugated Microporous Polymer with Enhanced Hydrogen Storage Performance.

Hydrogen storage is a primary challenge for using hydrogen as a fuel. With ideal hydrogen storage kinetics, the weak binding strength of hydrogen to sorbents is the key barrier to obtain decent hydrogen storage performance. Here, we reported the rational synthesis of a methyllithium-doped naphthyl-containing conjugated microporous polymer with exceptional binding strength of hydrogen to the polymer guided by theoretical simulations. Meanwhile, the experimental results showed that isosteric heat can reach up to 8.4 kJ mol(-1) and the methyllithium-doped naphthyl-containing conjugated microporous polymer exhibited an enhanced hydrogen storage performance with 150 % enhancement compared with its counterpart naphthyl-containing conjugated microporous polymer. These results indicate that this strategy provides a direction for design and synthesis of new materials that meet the US Department of Energy (DOE) hydrogen storage target.

High Uric Acid (UA) Negatively Affects Serum Tartrate-Resistant Acid Phosphatase 5b (TRACP 5b) Immunoassay.

BACKGROUND: Bone metastases often occur in the majority of patients with advanced cancer, such as prostate cancer, lung cancer and breast cancer. Serum tartrate-resistant acid phosphatase 5b (TRACP 5b), a novel bone resorption marker, has been used gradually in the clinics as a specific and sensitive marker of bone resorption for the early diagnosis of cancer patients with bone metastasis. Here, we reported that high concentrations of uric acid (UA) lead to decrease of TRACP 5b levels and determined whether TRACP 5b level was associated with UA in interference experiment. METHODS: A total of 77 patients with high concentrations of UA and 77 healthy subjects were tested to evaluate the differences in their TRACP 5b levels. Serial dilutions of UA were respectively spiked with a known concentration of TRACP 5b standard sample, then Serum TRACP 5b was detected by using bone TRAP® Assay. A correction equation was set to eliminate UA-derived TRACP 5b false-decrease. The effect of this correction was evaluated in high-UA individuals. RESULTS: The average TRACP level of the high-UA individuals (1.47 ± 0.62 U/L) was significantly lower than that of the healthy subjects (2.62 ± 0.63 U/L) (t-test, p < 0.0001). The UA correction equation derived: ΔTRACP 5b = -1.9751lgΔUA + 3.7365 with an R2 = 0.98899. Application of the UA correction equation resulted in a statistically non-significant difference in TRACP 5b values between the healthy subjects and high-UA individuals (p = 0.24). CONCLUSIONS: High UA concentrations can falsely decrease TRACP 5b levels due to a method-related systematic error. To avoid misdiagnoses or inappropriate therapeutic decisions, increased attention should be paid to UA interference, when TRACP 5b is used for early diagnosis of cancer patients with bone metastasis, evaluation of the aggressiveness of osteosarcoma or prediction of survival in prostate cancer and breast cancer with bone metastases.

Extraordinary capability for water treatment achieved by a perfluorous conjugated microporous polymer.

Oils, organic solvents, dyes, and heavy metal ions are primary pollutants in water resources. Currently, no sorbent material can effectively remove these types of pollutants simultaneously. Here we report a perfluorous conjugated microporous polymer with superhydrophobicity and a large surface area, which exhibits outstanding adsorption capacities, kinetics, and recyclability for a wide range of organic solvents, oils, dyes, and heavy metal ions. The adsorption capacities of this polymer, 1376.7 mg g(-1) for Congo red, 808.2 mg g(-1) for Pb(II) and 303.2 mg g(-1) for As(V), are higher than the adsorption capacities of any previously described porous materials. Our theoretical calculation reveals that the superior properties of this polymer are due to fluorination and triple bonds within the polymer. A benchmark experiment indicates that this polymer can efficiently remove these pollutants simultaneously. Application of this polymer may lead to the development of next-generation reusable and portable water purification appliances.

[Study on packaging-induced stress in 4 mm cavity length high-power single emitter semiconductor laser].

To reduce packaging-induced stress of long cavity length high-power single emitter semiconductor laser, the relationship between the stress and the wavelength shift was deduced on the basis of the theory that the stress can change the band gap. A method was developed for quantitatively calculating the stress by measuring the emission spectrum of the laser under pulse conditions. The results show that the soldering quality is a critical factor affecting thermal stress. The difference in stress can exceed 300 MPa due to the difference in soldering quality. By optimizing the reflowing soldering curve of the laser, the stress of the laser drops from 129.7 to 53.4 MPa. This method can also effectively solve the problem that the stress varies with storage time. This work demonstrates that the measurement and analysis of the emission spectrum of the laser can provide a useful method to study packaging stress of the high-power single emitter semiconductor laser. It is also an available means to evaluate and analyze soldering quality.

Preparation of lysine-coated magnetic Fe2O3 nanoparticles and influence on viability of A549 lung cancer cells.

OBJECTIVE: To explore the effect of lysine-coated oxide magnetic nanoparticles (Lys@MNPs) on viability and apoptosis of A549 lung cancer cells. METHODS: Transmission electron microscopy (TEM), vibrating sample magnetometer (VSM) and Zeta potentiometric analyzer were employed to characterize Lys@MNPs. Then Lys@MNPs and lung cancer A549 cells were co-cultured to study the effect of Lys@MNPs on cell viability and apoptosis. The pathway of Lys@MNPs entering A549 cells was detected by TEM and cell imaging by 1.5 T MRI. RESULTS: Lys@MNPs were 10.2 nm in grain diameter, characterized by small size, positive charge, and superparamagnetism. Under low-dose concentration of Lys@MNPs (<40 µg/mL), the survival rate of A549 cells was decreased but remained higher than 95% while under high-dose concentration (100 µg/mL), the survival ratewas still higher than 80%, which suggested Lys@MNPs had limited influence on the viability of A549 cells, with good biocompatibility and and no induction of apoptosis. Moreover, high affinity for cytomembranes, was demonstrated presenting good imaging effects. CONCLUSION: Lys@MNPs can be regarded as a good MRI negative contrast agents, with promising prospects in biomedicine.

Efficient fixation of CO2 by a zinc-coordinated conjugated microporous polymer.

Zinc-coordinated conjugated microporous polymers (Zn-CMPs), prepared by linking salen zinc and 1,3,5-triethynylbenzene, exhibit extraordinary activities (turnover frequencies of up to 11600 h(-1) ), broad substrate scope, and group tolerance for the synthesis of functional organic carbonates by coupling epoxides with CO2 at 120 °C and 3.0 MPa without the use of additional solvents. The catalytic activity of Zn-CMP is comparable to those of homogeneous catalysts and superior to those of other heterogeneous catalysts. This catalyst could be reused more than ten times without a significant decrease in performance.

[Comparison of heterotrophic nitrification and aerobic denitrification system by strain qy37 and its accelerating removal characteristic of NH4+ -N].

The characterization in nitrogen removal of a heterotrophic nitrification-aerobic denitrification bacteria (qy37) was studied. A strain coded as qy37 which had simultaneous heterotrophic nitrifying and aerobic denitrifying ability was screened. In the light of its morphological and physiological characters as well as their sequence analysis of the 16S rDNA, strain qy37 was identified as Pseudomonas sp.. In heterotrophic nitrifying system utilized ammonium chloride as nitrogen source, the concentration of NH4+ -N reduced from 138.52 mg/L to 7.88 mg/L and COD reduced from 2408.39 to 1177.49 mg/L by strain qy37 in 32 hours, the maximum accumulation of NH2OH and NO2- -N were 9.42 mg/L and 0.02 mg/L respectively, it was speculated that NH2OH was transformed to N2O and N2 directly by strain qy37. In aerobic denitrifying system utilized sodium nitrite as nitrogen source, the concentration of NO2- -N reduced from 109.25 mg/L to 2.59 mg/L by strain qy37 in 24 hours, and the maximum accumulation of NH2OH was 3.28 mg/L. Compared with heterotrophic nitrifying system, aerobic denitrifying system had a higher bacterial growth whereas the lower removal rate of TN and COD, as well as the accumulation of NH2OH. NO3- -N was also detected in aerobic denitrifying system. It is considered that the upgrowth of bacterium and utilization of energy in aerobic denitrifying system were more efficient than that in heterotrophic nitrifying system. In heterotrophic nitrification-aerobic denitrification system, the removal rate of NH4+ -N improved 37.31% in 16 hours than that in heterotrophic nitrifying system, the accumulation of NH2OH was less but N2O was higher than that in both heterotrophic nitrifying system and aerobic denitrifying system.

[Bioaugmentation for shortcut nitrification in SBR treating for sewage containing sea water by nitrification-aerobic denitrification bacteria].

The feasibility of heterotrophic nitrification-aerobic denitrification bacteria applied in shortcut nitrification system was studied. Four heterotrophic nitrification-aerobic denitrification strains mixed with halotolerant activated sludge was added into SBR in order to test their bioaugmentation ability for shortcut nitrification system, which was treating for sewage containing sea water, and the difference between bioaugmentation system and original system was compared. The results showed that the maximum accumulation of NO2(-) -N in bioaugmentation system was 34.92% lower than that in original system, and the time of maximum accumulation of NO2(-) -N was 2 hours earlier than that in original system. The TN and COD was continuously decreasing in the later phase of nitrification in bioaugmentation system, and finally the removal rate of TN and COD were 15.24% and 5.39% higher than that in original system respectively, as well as the removal rate of NH4(+) -N and the nitrosation rate were 6.85% and 14.47% higher than that in original system. And the pH was 0.46 higher than that in original system, whereas the ORP was 25.84 mV lower. It was considered that the function of heterotrophic nitrification-aerobic denitrification bacteria should strengthen the performance of bioaugmentation system. When the seawater content raised to 70%, the stability of bioaugmentation system was better than that in original system, and the current that transforming shortcut nitrification to complete nitrification was restrained by heterotrophic nitrification-aerobic denitrification bacteria effectively. The number of heterotrophic nitrification-aerobic denitrification bacteria was changed when bioaugmentation system and original system ran in different phase and the bacteria had a great loss with the discharge of activated sludge. These results may provide a theoretical reference about the feasibility that the heterotrophic nitrification-aerobic denitrification bacteria applied in shortcut nitrification system.