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CD1E, one of the most important glycolipid antigens on T cell membranes, is required for glycolipid antigen presentation on the cell surface. Cell-based recombinant expression systems have many limitations for synthesizing transmembrane proteins such as CD1E, including low protein yields and miss folding. To overcome these challenges, here we successfully synthesized high-quality soluble CD1E using an E.coli cell-free protein synthesis system (CFPS) with the aid of detergent. Following purification by Ni2+ affinity chromatography, we were able to obtain CD1E with ≥90% purity. Furthermore, we used the string website to predict the protein interaction network of CD1E and identified a potential binding partner━B2M. Similarly, we synthesized soluble B2M in the E.coli CFPS. Finally, we verified the interaction between CD1E and B2M by using Surface Plasmon Resonance (SPR). Taken together, the methods described here provide an alternative way to obtain active transmembrane protein and may facilitate future structural and functional studies on CD1E. Cell-based recombinant expression systems have many limitations for synthesizing transmembrane proteins such as CD1E, including low protein yields and miss folding. To overcome these challenges, here we successfully synthesized high-quality soluble CD1E using an E.coli cell-free protein synthesis system (CFPS) with the aid of detergent. Following purification by Ni2+ affinity chromatography, we were able to obtain CD1E with ≥90% purity. Furthermore, we used the Surface Plasmon Resonance (SPR) to verified the interaction between CD1E and B2M. The methods described here provide an alternative way to obtain active transmembrane protein and may facilitate future structural and functional studies on CD1E. [Display omitted] • Cell-based protein expression systems have limitations for producing membrane proteins, including low yields and solubility. • The cell-free protein expression system saves time and improves overall production of functional full-length proteins. • Proteins that can be used to study protein-protein interactions were successfully synthesized by the cell-free protein expression systems. • The SPR result reveals the precise affinity between CD1E and B2M. [ABSTRACT FROM AUTHOR]

[Display omitted] • Reveal the concentration characteristics of three different types of VOCs. • Explore the drivers of photochemically consumed VOCs to generate O 3. • Quantify the effect of photochemical consumed VOCs sources on O 3 formation. Ground-level ozone (O 3) pollution has received widespread attention because its rising trend and adverse ecological impacts. However, the extremely strong photochemical reactions of its precursor volatile organic compounds (VOCs) increase the difficulty of reducing VOCs emissions to alleviate O 3. Here, we carried out a one-year comprehensive observation in two representative cities, Tianjin (TJ, Northern China) and Guangzhou (GZ, Southern China). By revealing the concentration characteristics of three different types of VOCs, i.e., initial VOCs without photochemical reaction (In-VOCs), consumed VOCs (C-VOCs), and measured VOCs after the reaction (M-VOCs), we elucidated the important role of C-VOCs in the formation of O 3. Although the overall trends were similar in both cities, the average concentration level of VOCs in GZ was 8.2 ppbv higher than that in TJ, and the photochemical loss of VOCs was greater by 2.2 ppbv. In addition, various drivers affecting O 3 generation from C-VOCs were specifically explored, and it was found that most alkenes of TJ were key substances for rapid O 3 formation compared to aromatics of GZ. Meanwhile, favorable meteorological conditions such as high temperature (T > 31 °C in TJ, and T > 33 °C in GZ), low relative humidity (56% in TJ and 45% in GZ), and stable atmospheric environment (proper pressure and gentle wind speed) also contribute to the generation of O 3. More importantly, we combined chemical kinetics and receptor model to quantify the three-type VOCs source contributions and assess the potential impact of C-VOCs sources on O 3 production, thus proposing environmental abatement technologies corresponding to the three types of VOCs. The differences in the comparison results of the three-type VOCs highlight the need to reduce O 3 pollution from C-VOCs sources, which provides insights for future clean air policies development. [ABSTRACT FROM AUTHOR]

With structural diversity of water-soluble polysaccharides, their precise quantitative analysis by phenol‑sulfuric acid method becomes more difficult and challenging. In this study, the quantification analysis of dextran and glucose in phenol sulfuric acid method was compared in this paper. When the concentration is below 90 μg/mL, the quantification of glucose is close to theoretical value, however, glucose derivatives have significantly different absorption. Later, quantitative factors of water-soluble polysaccharide in RID measurement were investigated. The optimum temperature was 40 °C and linear range was 0.3125–10.0 mg/mL in RID for dextrans (1.0–500 kDa) and glucose derivatives. Method validation studies of the RID method were further performed and compared to conventional phenol sulfuric acid method, which demonstrated that RID measurement is more reliable and satisfactory method. The intervention of water-soluble impurity in RID response should be well control below 6% (w/w). By comparison, the RID measurement could well alleviate drawbacks in phenol‑sulfuric acid method. [Display omitted] [ABSTRACT FROM AUTHOR]

Through hot water extraction, protein removal and chromatographic purification, DWPP-Is was found to be the major polysaccharide present in the stem of D. wardianum. The Mn and Mw of DWPP-Is were 29.0 kDa and 98.6 kDa, respectively. Furthermore, mannose and glucose were found to be the most abundant monosaccharides in DWPP-Is. Their backbones consist of (1 → 4)- β - d -Glc p and O -acetylated (1 → 4)- β - d -Man p , which are similar to the structures of other anti-tumour Dendrobium polysaccharides. The inhibition rate of DWPP-Is treatment on SPC-A-1 cells (2 mg/mL, 72 h) reached 56.0%. Intragastric administration of DWPP-Is on A549 tumour-bearing KM mice (10 mg/mL, 0.2 mL) exhibited similar inhibition ratios to that of erlotinib hydrochloride (2 mg/mL). Moreover, the highest inhibition was observed in P-CK treatment combined with DWPP-Is, reaching an inhibition rate of 23.4%. These results suggest that DWPP-Is has the potential to be a functional agent for lung cancer prevention. • Three polysaccharide fractions were extracted from the stem of Dendrobium wardianum. • The Mn and Mw of DWPP-Is were 29.0 kDa and 98.6 kDa, respectively. • DWPP-Is was major composed of mannose and glucose. • The backbones of DWPP-Is was consist of (1 → 4)- β - d -Glc p and O -acetylated (1 → 4)- β - d -Man p. • DWPP-Is exhibited good inhibition on SPC-A-1 cells in vitro and A549 cells in vivo. [ABSTRACT FROM AUTHOR]

With advances in vehicle emission control technology, updating source profiles to meet the current requirements of source apportionment has become increasingly crucial. In this study, on-road and non-road vehicle particles were collected, and then the chemical compositions of individual particles were analyzed using single particle aerosol mass spectrometry. The data were grouped using an adaptive resonance theory neural network to identify signatures and establish a mass spectral database of mobile sources. In addition, a deep learning-based model (DeepAerosolClassifier) for classifying aerosol particles was established. The objective of this model was to accomplish source apportionment. During the training process, the model achieved an accuracy of 98.49 % for the validation set and an accuracy of 93.36 % for the testing set. Regarding the model interpretation, ideal spectra were generated using the model, verifying its accurate recognition of the characteristic patterns in the mass spectra. In a practical application, the model performed hourly source apportionment at three specific field monitoring sites. The effectiveness of the model in field measurement was validated by combining traffic flow and spatial information with the model results. Compared with other machine learning methods, our model achieved highly automated source apportionment while eliminating the need for feature selection, and it enables end-to-end operation. Thus, in the future, it can be applied in refined and online source apportionment of particulate matter., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

The bioactivity of tea polysaccharides (TPs) has been widely reported, but studies to date have focused on green tea. Some human health investigations have implied that black tea may possess potential antidiabetic effects, but less is known about their potential role and related antidiabetic mechanism. The present study was, therefore, conducted to investigate the chemical properties and antidiabetic activity of TPs from black tea. Monosaccharide composition revealed that Alduronic acid (77.8 mol%) considerably predominated in the fraction. TP conformation analysis indicated that three components in TPs were all typical of high-branching structures. Oral administration of TPs could effectively alleviate fasting blood glucose in type 2 diabetes mellitus (T2D) mice, with the values 23.6 ± 1.42, 19.6 ± 2.25, and 16.4 ± 2.07 mmol/L in the 200, 400, and 800 mg/kg·BW groups, respectively. Among these TPs groups, the 800 mg/kg·BW groups significantly decreased by 37.88% when compared with the T2D+water group ( p < 0.05). Further studies demonstrated that TP treatment upregulated the expression of p-Akt/p-PI3K ( p < 0.001). Additionally, TP treatment significantly promoted glucose transporter protein 2 (GLUT2) translocation in the liver ( p < 0.001). These findings suggest that TPs from black tea protect against T2D by activating PI3K/Akt/GLUT2 signaling and might serve as a novel therapeutic candidate for T2D., Competing Interests: The authors declare that they have no conflicts of interest concerning this article.

The structure and bioactivity of a novel polysaccharide from Dendrobium Chrysotoxum Lindl (DCP-1) were investigated. The crude polysaccharides of Dendrobium Chrysotoxum Lindl (DCP) were extracted by hot water extraction, and the protein was removed by enzymatic hydrolysis and Sevage. After purification, the chemical structure of polysaccharides was identified by infrared spectroscopy, methylation analysis and nuclear magnetic resonance spectroscopy. Then, a mouse model of acute kidney injury (AKI) was constructed using lipopolysaccharide (LPS), and pretreated with DCP. Structure characterization demonstrated that the number-average molecular weight and mass average molar mass of DCP-1 were 28.43 kDa and 15.00 kDa, respectively. DCP-1 mainly consisted of mannose (37.8 %) and glucose (55.6 %). The main linkage types of DCP-1 were contained 1,4-Linked Manp and 1,4-Linked Glcp. And DCP-1 was demonstrated to be an O-acetylglucomannan with β-ᴅ-configuration in pyranoid form. Besides, the bioactivity of DCP was further investigated. The results showed that DCP exhibited notable anti-inflammatory activity in LPS-induced AKI mice. After treated with DCP, the creatinine (CREA) and urea nitrogen (BUN) in serum were successfully down-regulated in AKI mice. DCP treatment prevented the characteristic morphological changes of LPS-induced renal tubular injury. The results showed that DCP treatment significantly reduced the concentration of oxidative damage indicators (MDA, SOD) and the expression of inflammatory indices (TNF-α, IL-6, MCP-1, COX-2). In general, the newly extracted polysaccharide DCP showed excellent nephroprotective effect, which enabled it to be an ideal natural medicine for kidney diseases therapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The outbreak of novel coronavirus pneumonia in Wuhan, Hubei Province, in 2019 and its rapid spread across the country caused severe public panic in China. The purpose of this study was to investigate the mental health problems of children's chaperones at the emergency clinic during the coronavirus disease 2019 (COVID-19) outbreak and to analyze the related influencing factors. A total of 260 chaperones for children in the emergency department participated in this cross-sectional study through the questionnaire constellation platform. The survey period was from February to June 2021. Information collected included demographic data and mental health scales. The Self-Assessment Scale for Anxiety, the Self-Rating Scale for Depression, and the Pittsburgh Sleep Quality Index assessed anxiety, depression, and sleep quality, respectively. Logistic regression was used to analyze influential factors associated with mental health problems. The prevalence of depression, anxiety, and sleep disorders among family members accompanying children attending the emergency room was 41.54%, 20.00%, and 93.08%, respectively, with 21.54% of family members suffering from moderate sleep disorders. Univariate analysis showed that being in Wuhan or not during the city closure (X2 = 8.61, P < .01) was strongly associated with the occurrence of depression; female (X2 = 4.87, P = .03), working or not (X2 = 6.39, P = .01) and fear of going to the hospital (X2 = 7.80, P = .01) were key factors for the occurrence of anxiety symptoms; Knowledge of transmission routes and prevention of COVID-19 (X2 = 12.56, P = .03) was a key factor for sleep disorders; logistic stepwise regression analysis showed that fear of going to the hospital was a risk factor for anxiety symptoms (odds ratio = 2.51, P < .01, 95% confidence interval = 1.30-4.85). Our findings suggest that mental health problems were prevalent among family members accompanying children attending the emergency department during the COVID-19 outbreak, with a high prevalence of sleep disturbances in particular. Relevant factors included presence or absence in Wuhan during the outbreak closure, gender, work or absence, and fear of hospital visits. There is a need to focus on the mental health distress of the chaperones for children in the emergency department, and to provide timely intervention and diversion., Competing Interests: The authors have no conflicts of interest to disclose., (Copyright © 2023 the Author(s). Published by Wolters Kluwer Health, Inc.)

Objective: To assess the association of c.109G>A (p.V37I) variant of the GJB2 gene and its types with the risk of deafness., Methods: PubMed, Embase, Cochrane Library, CNKI, Wanfang, and VIP database were searched for cases with GJB2 gene c.109G>A (p.V37I) variant and its compounds with variants of other sites from case-control studies, cohort studies and cross-sectional studies. The search time was from the establishment of database to April 2021. Two researchers have independently screened the literature according to the inclusion and exclusion criteria, extracted the data, and evaluated the included studies according to the criteria. Stata 12.0 software was used for the meta-analysis and publication bias analysis, and a sensitivity analysis was also carried out when necessary., Results: A total of 22 articles (17 in English and 5 in Chinese) were included. There were 7455 cases in the deafness group and 10 464 cases in the control group. The results of meta-analysis showed the c.109G>A (p.V37I) variant to be strongly associated with the risk of deafness (OR: 3.56, 95%CI: 2.31-5.47, P < 0.001). Analysis based on the mutational type also suggested c.109G>A (p.V37I) homozygosity (OR: 11.36, 95%CI: 5.93-21.74, P < 0.001) and compound loss of heterozygosity mutations (OR: 9.27, 95%CI: 3.97-21.64, P < 0.001) to be strongly associated with the risk of deafness. By contrast, heterozygous c.109G>A (p.V37I) variant (OR: 1.20, 95%CI: 0.72-2.00, P = 0.478) and compound heterozygous missense mutation (OR: 1.54, 95%CI: 0.98-2.44, P = 0.063) are not strongly associated with the risk., Conclusion: The homozygous c.109G>A (p.V37I) variants of the GJB2 gene and its compound deletional mutation with another GJB2 allele can significantly increase the risk of deafness. Heterozygous c.109G>A (p.V37I) variant of the GJB2 gene or its compound with a missense mutation of another GJB2 allele do not increase the risk.

Objective: To observe the secondary prevention efficacy of subcutaneous immunotherapy in children with allergic rhinitis（AR） and cough variant asthma（CVA） and to analyze its effect on the levels of serum sIgG4, IL-27 and IL-33. Method: The clinical data of 112 children aged 5-12 years with AR and CVA were retrospectively analyzed and divided into control group（52 cases） and SCIT group（60 cases）. The patients were followed up for 3 years. The control group was received symptomatic treatment only, and the SCIT group was received SCIT on the basis of the control group. The numbers of cases of the two groups of children who produced new allergens and developed CA were analyze during the 3-year treatment. Changes in serum sIgG4, IL-27, IL-33 levels, TNSS, DCSS, NCSS, TRMS, TCMS, VAS score, and FEV1% before and after treatment were analyzed. Result: During the treatment, 4 patients（6.67%） in the SCIT group produced the new allergen, and 20 patients（38.46%） in the control group（χ²=16.73, P <0.05）. There were only 3 cases（5.00%） in the SCIT group, which developed into CA, while 15 cases（28.85%） in the control group. The difference between the groups was statistically significant（χ²=11.74, P <0.05）. Compared with baseline, serum levels of sIgG4 and IL-27 in both groups were significantly increased after 3 years of treatment（ P <0.05）, while serum levels of IL-33 were significantly decreased（ P <0.05）. After 3 years of treatment, serum levels of sIgG4 and IL-27 in the SCIT group were significantly higher than those in the control group, and serum levels of IL-33 were significantly lower than those in the control group（ P <0.05）. Compared with baseline, TNSS, DCSS, NCSS, TRMS, TCMS, VAS, and FEV1% in both groups were significantly improved at 1, 2, and 3 years of treatment（ P <0.05）. There was no significant difference in TNSS, DCSS, NCSS, TRMS, TCMS, VAS and FEV1% between the two groups at baseline（ P >0.05）, while after 1, 2 and 3 years of treatment the above indicators in the SCIT group were significantly better than those in the control group（ P <0.05）. Conclusion: SCIT treatment can prevent AR with CVA patients from producing new allergens and developing into CA, and improve serum sIgG4 and IL-27 and IL-33 levels., Competing Interests: The authors of this article and the planning committee members and staff have no relevant financial relationships with commercial interests to disclose., (Copyright© by the Editorial Department of Journal of Clinical Otorhinolaryngology Head and Neck Surgery.)

Background: The risk factors for multi-drug resistant infection (MDRI) in the pediatric intensive care unit (PICU) remain unclear. It's necessary to evaluate the epidemiological characteristics and risk factors for MDRI in PICU, to provide insights into the prophylaxis of MDRI clinically., Methods: Clinical data of 79 PICU children with MDRI were identified, and 80 children in PICU without MDRI in the same period were selected as control group. The related children's characteristics, clinical care, microbiologic data, treatments provided, and outcomes of the patients with were reviewed and collected. Univariate and multivariate logistic regression analyses were performed to identify the potential risks of MDRI in PICU., Results: Of the diagnosed 79 cases of MDRI, there were28 cases of CR-AB, 24 cases of MRSA, 22 cases of PDR-PA,3 cases of VRE and 2 cases of CRE respectively. Univariate analyses indicated that the length of PICU stay, the duration of mechanical ventilation > 5 days, parenteral nutrition, coma, urinary catheter indwelling, invasive operation, 2 or more antibiotics use were associated with MDRIs (all p < 0.05); The logistic multiple regression analyses indicated that coma, parenteral nutrition, 2 or more antibiotics use and the duration of mechanical ventilation > 5 days were independent risk factors associated with MDRI (all p < 0.05)., Conclusions: This present study has identified several potentially modifiable risk factors for MDRI in PICU, it's conducive to take appropriate measures targeting risk factors of MDRI for health care providers to reduce MDRI.

This paper generalizes the stability test method via integral estimation for integer-order neutral time-delay systems to neutral fractional-delay systems. The key step in stability test is the calculation of the number of unstable characteristic roots that is described by a definite integral over an interval from zero to a sufficient large upper limit. Algorithms for correctly estimating the upper limits of the integral are given in two concise ways, parameter dependent or independent. A special feature of the proposed method is that it judges the stability of fractional-delay systems simply by using rough integral estimation. Meanwhile, the paper shows that for some neutral fractional-delay systems, the stability is extremely sensitive to the change of time delays. Examples are given for demonstrating the proposed method as well as the delay sensitivity.

Objective: To analyze the incidence and treatment of Clostridium difficile infection (CDI) in pediatric patients with antibiotic-associated diarrhea (AAD)., Method: Clinical data of totally 577 pediatric patients with AAD seen from January 2012 to January 2014 were collected; those children were divided according to age into 4 groups, 0.25 -1 year, >1 -4 years, >4 -12 years and >12 -18 years old groups, and 220 healthy children were enrolled as controls. CDI was tested by C. Diff Quik Chek Complete (QCC) and BD GeneOhm™ C. Diff Assay (BD-PCR) in all children, and the CDI incidence of four groups was added up. All pediatric patients with AAD were divided into mild, general and severe type according to different symptoms of diarrhea, and grading treatment, the general type and severe type of CDI children were treated with metronidazole and (or) vancomycin, afterwards, the results of grading treatment were analyzed., Result: The number of pediatric patients with AAD were 178, 177, 132 and 90 in 0. 25 - 1 year, > 1 -4 years, > 4 - 12 years and > 12 - 18 years old group, respectively. The positive rate of CDI (22. 0% (39/177)) in > 1 -4 years old AAD patients was very significantly higher compared to the controls (4% (4/91), P < 0. 001), the rate of CDI (21. 2% (28/132)) in > 4 - 12 years old AAD pediatric patients was significantly higher compared to the controls (4% (2/53), P = 0. 004), the rates of CDI in 0. 25 - 1 year and > 12 - 18years old AAD groups were not significantly different from that of the controls (P >0. 05). There were 285 mild type AAD children (no CDI children), 176 general type AAD children (including 47 CDI children), and 116 severe type AAD children (including 81 CDI children). After grading and symptomatic treatment, there were 16 recurrent diarrhea in 128 CDI patients (severe type AAD), and the rest recovered. Two cases were transferred for referral treatment, 2 cases died, and the rest 12 recurrent diarrhea children fully recovered after administration of metronidazole, vancomycin, probiotics and symptomatic treatment., Conclusion: The > 1 -12 years old AAD children had higher CDI rate than healthy children; administration of metronidazole and (or) vancomycin was effective for CD infection.