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Nitrogen in the bubbling gas was directly fixed into water by pulsed high-voltage discharge. When the discharge occurred, nitrogen could be dissociated to form active N species to take part in the aqueous chemical process. Nitrous acid (HN[O.sub.2]) was primarily produced, which was further converted into nitric acid (HN[O.sub.3]). With the formation of HN[O.sub.2] and HN[O.sub.3], the pH of the liquid decreased. The decrease in pH sped up the conversion from HN[O.sub.2] into HN[O.sub.3], thus resulted in an increase in the N[O.sup.-.sub.2] concentration at first and a decrease after a turning point. The nitrogen fixation rate with bubbling nitrogen was faster than that with bubbling air in distilled water. By discharge for about 30 min, HN[O.sub.2] was converted into HN[O.sub.3] as the final products. Its concentrations were 1.96 mmol x [L.sup.-1] with bubbling air and 2.34 mmol x [L.sup.-1] with bubbling pure nitrogen. The energy efficiencies were 2.08 x [10.sup.-9] and 2.48 x [10.sup.-9] mol x [J.sup.-1], respectively. Index Terms--Discharge in water, nitrate, nitrogen fixation, plasma.

Abstract: By applying pulsed high voltage discharge to a needle-mesh reactor that using seven acupuncture needles as discharge electrode and stainless steel wire mesh as ground electrode, nitrogen from bubbling gas could be fixed into NO2 − and NO3 − with equivalent mol H+ produced in the liquid phase and a small amount of NO and NO2 yielded in the gas phase. The HNO2 was originally formed and then converted into HNO3. The ·OH and H2O2 stimulated the conversion reaction from HNO2 to HNO3, which caused HNO2 concentration increased in the first 12min and then decreased until lower than its detection limit. The concentration of HNO3 still increased with discharge time. After 36min, HNO3 was the only and ultimate product in the liquid. The total yield of HNO2 and HNO3 could be affected by processing parameters such as electric factors of peak voltage and frequency, mesh size of ground electrode and content of nitrogen in N2/O2 bubbling. Increasing peak voltage or frequency, the total yield of HNO2 and HNO3 increased. Gas composition had a heavy impact on the fixation efficiency that obtained its maximum value at an oxygen content of 66.7% with bubbling O2/N2 gas. At the end of the 36min discharge, the HNO3 concentration with bubbling air was 2.215mmolL−1 at an applied voltage of 25kV, pulse repetition frequency of 140Hz and ground electrode mesh of 20×20. The energy yield was about 1.22g (HNO3)/kWh. [Copyright &y& Elsevier]

Objectives: Human leukocyte antigen (HLA) B27 is a susceptibility allele of ankylosing spondylitis (AS), and HLA-B27 antigen typing is an important indicator for clinical diagnosis of AS, but current typing methods such as sequence specific primer polymerase chain reaction (PCR-SSP) still possess limitation. Therefore, this study aims to analyze the correlation between B27 subtypes and susceptibility to AS in Hunan Province by applying high-resolution polymerase chain reaction-sequence-based typing (PCR-SBT)., Methods: Peripheral blood of 116 patients with suspected AS (suspected AS group) and 121 healthy volunteers (control group) admitted to the Second Xiangya Hospital from January 2020 to December 2020 were collected for HLA-B genotyping by PCR-SBT. Among the patients in the suspected AS group, 23 patients were finally diagnosed with AS (confirmed AS group), and the remaining 93 undiagnosed patients served as the non-confirmed AS group. PCR-SBT and PCR-SSP were used to detect HLA-B27 typing in 116 patients with suspected AS, and the results of the 2 methods were compared., Results: The HLA-B27 allele frequency in the suspected AS group was significantly higher than that in the control group [11.63% vs 2.48%; P <0.001, odds ratio ( OR )=5.18, 95% confidence interval ( CI ) 2.097 to 12.795]. B*27:04, B*27:05, B*27:06, and B*27:07 were detected in the suspected AS group and the control group. The frequency of the B*27:04 allele in the suspected AS group was significantly higher than that in the control group (9.48% vs 1.24%; P <0.001, OR =8.346, 95% CI 2.463 to 28.282). The positive rate of B27 in the suspected AS group and the confirmed AS group (B27+/+ and B27+/-) was significantly higher than that in the control group ( χ 2 =16.579, P <0.001; χ 2 =94.582, P <0.001, respectively). Among the confirmed AS group, 21 were HLA-B27 carriers, and the B27 positive rate in the confirmed AS group was 91.3%. PCR-SBT could achieve high resolution typing of the HLA-B gene locus, with higher sensitivity, specificity, positive predictive value, negative predictive value, and accuracy than PCR-SSP., Conclusions: PCR-SBT typing analysis shows a strong correlation between HLA-B * 27:04 and AS in Hunan province. The PCR-SBT method can be used as the preferred option for the auxiliary diagnosis of clinical AS.

The structures of chimeric antigen receptors (CARs) currently designed for natural killer (NK) cells are mostly based on knowledge gained about CAR-T cells. Although these CAR-NK cells have shown promising effects, there are still many limitations to their application. In this study, we designed a soluble NK-CAR since the membrane protein NKG2D expressed by NK cells can directly trigger NK cell cytotoxicity by binding with the ligand MICA. This CAR is composed of three segments: the extracellular domain of MICA, an anti-CD20 single-chain variable fragment (anti-CD20 ScFv), and a human IgG Fc component. The nucleotide sequence of the soluble NK-CAR was cloned into a eukaryotic expression vector and expressed in suspension HEK293 cells, and the recombinant NK-CAR protein was then purified in a Staphylococcus aureus protein A column. The novel NK-CAR exhibited bifunctional activity, recognizing both the CD20 antigen of target cells and the NKG2D receptor of NKL cells. The NK-CAR activated the NKG2D receptor signaling pathway, causing NKL cells to express CD107a and secrete interferon-gamma. The soluble NK-CAR mediated the NKL cell killing of CD20 + Daudi cells in vitro, with a 1 µg/mL concentration inducing the maximum killing effect. Moreover, 51.7% (p < 0.01) of Daudi cells were killed at the effector-to-target ratio of 10:1. In the presence of recombinant rMICA and NKG2D-Ig proteins, this killing effect was reduced to 30% (P < 0.01) owing to competitive interference. Our results highlight the clinical application potential of this novel immunotherapy for killing target tumor cells., Competing Interests: Disclosure Statement The authors have no conflicts of interest to declare., (copyright: © 2022 Liu et al.)

Glomangiomatosis is benign but may manifest as diffusely, locally infiltrating lesions and recur after simple excision. However, conservative treatment should be advocated. The authors report a recent case in which the lesion occurred in the paravertebral area. The patient was a 39-year-old Chinese man who complained of chronic lumbago for 20 years. The clinicopathological features, in conjunction with the immunostaining pattern and ultrastructural features, confirmed the diagnosis. Glomangiomatosis is an extremely rare soft-tissue lesion. To the best of authors' knowledge, only 10 cases have been reported in the English-language literature worldwide, and the current case is the first to represent a lesion arising from the paravertebral area. The authors review the English-language literature in glomangiomatosis.