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Alpha1-antitrypsin is a kind of plasma protein that requires a sequence of different fractionation steps to get generally. To report an effective process for isolating and purifying alpha1-antitrypsin from Cohn Fraction IV based upon a new immunoaffinity chromatography medium, named “Alpha-1 Antitrypsin Select,” characterization of alpha1-antitrypsin (α1-AT) was performed by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), Western blot, and tandem mass spectroscopy. Total protein content was determined by the method of Bradford under visible light absorption at 595 nm. Pretreatment process and the immunoaffinity chromatography step achieved a 60.35 ± 1.39% yield. Thus, an overall 71.68 ± 1.32 fold increase in purity and a 41.88 ± 6.98% yield were obtained from plasma. The α1-AT had a specific activity of about 1.00–1.05 PU/mg. This technique will develop an effective process for isolating and purifying, with high purity and specific activity, alpha1-antitrypsin from Cohn Fraction IV or human whole plasma, which could be an efficient and scaled-up method for alpha1-antitrypsin products purification. [ABSTRACT FROM AUTHOR]

In order to increase the yield of prothrombin complex concentrates (PCCs) and to reduce their associated thrombotic risks, the influence of washing conditions on the yield, purity, and balance of coagulation factors (FII, FVII, FIX, and FX), and inhibitor proteins (PC, PS, PZ, and AT [antithrombin]) in PCCs was investigated by orthogonal testing, in which three variables (sodium citrate, NaCl, and pH) and their three levels were selected. It was found that AT yield and purity were extraordinarily low, and at lower NaCl content, the general yield, purity, and balance were higher, lower, and better, respectively; however, the results became contrary at higher NaCl. Moreover, within the investigated levels, NaCl was the first determinant for the yield except AT and the purity except FVII, PC, PS, and AT. Sodium citrate was the first determinant for AT yield and FVII, PS, and AT purity. The yield except FII, PS, and AT decreased and the purity except PC increased with increase of sodium citrate content. Just for PC purity, pH was the first determinant. The effect with pH fluctuation on the yield and purity was characteristically unobvious. The outcome undoubtedly supplies the guidance to further improve PCCs. [ABSTRACT FROM PUBLISHER]

Intravenous immunoglobulin (IVIg) is increasingly used for the treatment of autoimmune and systemic inflammatory diseases with both licensed and off‐label indications. Recent studies indicated that IVIg‐mediated immunomodulation and anti‐inflammation are closely associated with the IgG sialylation, especially with IgG crystallizable fragment (Fc) sialylation. The sialic acid levels of the IgG molecules and Fc fragments in 12 IVIg preparations from six Chinese manufacturers were evaluated. The Fc fragments were derived from the papain digestion of IVIg, followed by affinity and size exclusion chromatography. The sialic acid levels in Fc fragments and IVIg preparations were determined by high‐performance liquid chromatography with fluorescence detection, after the sialic acid residues were released from the proteins. The results showed that the sialic acid levels in Chinese IVIg preparations ranged from 0.875 (mol/mol IgG) to 1.085 (mol/mol IgG), and the sialic acid levels in Fc fragments were from 0.321 (mol/mol Fc) to 0.361 (mol/mol Fc). Furthermore, the sialic acid levels of IVIg preparations and Fc fragments from different Chinese manufactures were significantly different. These findings will contribute to an increased understanding of Chinese IVIg preparations and the relationship between the sialic acid levels in IVIg preparations and their clinical efficacy in future clinical studies. [ABSTRACT FROM AUTHOR]

Aims: We evaluated whether Subjective Cognitive Decline (SCD) subtypes could be empirically derived within the Sino Longitudinal Study on Cognitive Decline (SILCODE) SCD cohort and examined associated neuroimaging markers, biomarkers, and clinical outcomes. Methods: A cluster analysis was performed on eight neuropsychological test scores from 124 SCD SILCODE participants and 57 normal control (NC) subjects. Structural and functional neuroimaging indices were used to evaluate the SCD subgroups. Results: Four subtypes emerged: (1) dysexecutive/mixed SCD (n = 23), (2) neuropsychiatric SCD (n = 24), (3) amnestic SCD (n = 22), and (4) cluster‐derived normal (n = 55) who exhibited normal performance in neuropsychological tests. Compared with the NC group, each subgroup showed distinct patterns in gray matter (GM) volume and the amplitude of low‐frequency fluctuations (ALFF). Lower fractional anisotropy (FA) values were only found in the neuropsychiatric SCD group relative to NC. Conclusion: The identification of empirically derived SCD subtypes demonstrates the presence of heterogeneity in SCD neuropsychological profiles. The cluster‐derived normal group may represent the majority of SCD individuals who do not show progressive cognitive decline; the dysexecutive/mixed SCD and amnestic SCD might represent high‐risk groups with progressing cognitive decline; and finally, the neuropsychiatric SCD may represent a new topic in SCD research. [ABSTRACT FROM AUTHOR]

Biosensors featuring single molecule detection present huge opportunities as well as challenges in food safety inspection, disease diagnosis, and environmental monitoring. Single‐molecule detection is largely lacking of high enough activity, precision molecule selectivity, and understanding in the exact operating mechanism. Single‐atom catalysts (SACs), especially those metals‐nitrogen‐carbon that mimic the natural metalloenzyme structure, and with well‐defined metal atom bond configurations, high level of molecular selectivity, and easy fabrication, endow single molecule detections with practical‐use feasibilities. The recent advances in single‐atom catalysts also present new pathways in the key mechanism understandings. In this short review, we will first visit the brief history and advantages of SACs that have been explored only recently for molecule‐scale biosensors, where they are analogous and also differentiated from those nanozymes and natural metalloenzymes. Their applications in electrochemical, photochemical, and photoelectrochemical sensors are then discussed comprehensively by focusing on the different molecule‐scale sensing modes in achieving local coordination‐modulated signal amplifications. Finally, we identify new opportunities and challenges faced by these SACs‐based single molecule detections in the further development of biosensors. [ABSTRACT FROM AUTHOR]

5‐hydroxymethylfurfural (HMF), one of the most significant biomass‐derived renewable resources, has been widely utilized to create furan‐based value‐added chemicals such as 2,5‐diformylfuran (DFF), 5‐hydroxymethyl‐2‐furancarboxylic acid (HMFCA), 5‐formyl‐2‐furancarboxylic acid (FFCA), and 2,5‐furan dicarboxylic acid (FDCA). Indeed, DFF, HMFCA and FFCA are key intermediate products during the oxidation of HMF to FDCA. Herein, this review aims to demonstrate the recent advances in metal‐catalyzed oxidation of HMF into FDCA via two different reaction routes (HMF‐DFF‐FFCA‐FDCA and HMF‐HMFCA‐FFCA‐FDCA). All the four furan‐based compounds are comprehensively discussed by the selective oxidation of HMF. Additionally, various metal catalysts, reaction conditions, and reaction mechanisms used to obtain the four different products are systematically reviewed. It is anticipated that this review will provide related researchers with new perspectives and speed up the development of this field. [ABSTRACT FROM AUTHOR]

A novel ethanolic two-phase system (ETPS) composed of Pluronic®L-64 (PL 64) and deep eutectic solvents (DESs) was constructed for the separation of two similar flavonoids of naringin (Nar) and neohesperidin (Neo) from the pomelo peel. The selectivity (S) data showed that DES prepared from tetrabutylammonium bromide (N4444Br) and glycerol (Gly) had the optimal distribution efficiency for Nar and Neo standards. A binodal curve of N4444Br-Gly/PL 64/ethanol system fitted to the nonlinear Merchuk relationship showed that the biphasic region was narrow for ETPS. The influences of the mass ratio of DESs and PL 64, DES concentration, PL 64 concentration, molar ratio of DESs, temperature, phosphate buffer solution, and ethanolic pH were studied in single-factor experiments. Under the optimal conditions, the maximum extraction efficiency (ENar = 68.32%, ENeo = 86.09%), partition coefficient (KNar = 6.66, KNeo = 19.13), and S (2.88) were obtained in the DESs-rich (bottom) phase. N4444Br-Gly, Nar, and Neo with recovery yields of 78.12%, 66.61%, and 68.03%, respectively, had been recovered using D101 macroporous resin. This proposed ETPS is efficient and environmentally friendly and is expected to avail meaningful references for the separation of natural products with similar structures. [ABSTRACT FROM AUTHOR]

The state of charge (SOC) of lithium batteries is an important parameter of battery management systems. We aim at the problem that the noise variance is fixed during the estimation of the battery state by the unscented Kalman filter (UKF), which leads to low estimation accuracy. Lithium battery SOC estimation based on the UKF and whale optimization algorithm (WOA) is proposed. The first WOA is used to identify the parameters of the battery model. WOA–UKF is used to estimate the SOC of the battery, in which the observed noise variance and process noise variance of the UKF are updated through the second WOA, thereby the estimation accuracy is improved. The experimental results verify the effectiveness of the improved method. [ABSTRACT FROM AUTHOR]

As an emerging subclass of 2D materials, Xenes (e.g., borophene, silicene, germanene, stanene, phosphorene, arsenene, antimonene, and bismuthene) consist of one single element and have opened the door for various important applications. Benefiting from their impressive characteristics, including ultrathin folded structure, ultrahigh surface–volume ratio, excellent mechanical strength and flexibility, Xenes are considered as promising electrode materials in the field of electrochemical energy with large capacity, high rate, and high safety. This review provides a comprehensive summary of selected properties, synthetic challenges, and the latest theoretical and experimental advances in the energy‐related applications of Xenes, including Li/Na ion batteries, Li–S batteries, electrocatalysis, and supercapacitors. Finally, the challenges and outlook of this emerging field are discussed. [ABSTRACT FROM AUTHOR]