Endo-beta-N-acetylglucosaminidase (ENGase) is widely distributed in various organisms. The first reported ENGase activity was detected in Diplococcus pneumoniae in 1971. The protein (Endo D) was purified and its peptide sequence was determined in 1974. Three ENGases (Endo F1-F3) were discovered in Flavobacterium meningosepticum from 1982 to 1993. After that, the activity was detected from different species of bacteria, yeast, fungal, plant, mice, human, etc. Multiple ENGases were detected in some species, such as Arabidopsis thaliana and Trichoderma atroviride. The first preliminary crystallographic analysis of ENGase was conducted in 1994. But to date, only a few ENGases structures have been obtained, and the structure of human ENGase is still missing. The currently identified ENGases were distributed in the GH18 or GH85 families in Carbohydrate-Active enZyme (CAZy) database. GH18 ENGase only has hydrolytic activity, but GH85 ENGase has both hydrolytic and transglycosylation activity. Although ENGases of the two families have similar (β/α)8-TIM barrel structures, the active sites are slightly different. ENGase is an effective tool for glycan detection andglycan editing. Biochemically, ENGase can specifically hydrolyze β‑1,4 glycosidic bond between the twoN-acetylglucosamines (GlcNAc) on core pentasaccharide presented on glycopeptides and/or glycoproteins. Different ENGases may have different substrate specificity. The hydrolysis products are oligosaccharide chains and a GlcNAc or glycopeptides or glycoproteins with a GlcNAc. Conditionally, it can use the two products to produce a new glycopeptides or glycoprotein. Although ENGase is a common presentation in cell, its biological function remains unclear. Accumulated evidences demonstrated that ENGase is a none essential gene for living and a key regulator for differentiation. No ENGase gene was detected in the genomes of Saccharomyces cerevisiae and three other yeast species. Its expression was extremely low in lung. As glycoproteins are not produced by prokaryotic cells, a role for nutrition and/or microbial-host interaction was predicted for bacterium produced enzymes. In the embryonic lethality phenotype of the Ngly1-deficient mice can be partially rescued by Engase knockout, suggesting down regulation of Engase might be a solution for stress induced adaptation. Potential impacts of ENGase regulation on health and disease were presented. Rabeprazole, a drug used for stomach pain as a proton inhibitor, was identified as an inhibitor for ENGase. ENGases have been applied in vitro to produce antibodies with a designated glycan. The two step reactions were achieved by a pair of ENGase dominated for hydrolysis of substrate glycoprotein and synthesis of new glycoprotein with a free glycan of designed structure, respectively. In addition, ENGase was also been used in cell surface glycan editing. New application scenarios and new detection methods for glycobiological engineering are quickly opened up by the two functions of ENGase, especially in antibody remodeling and antibody drug conjugates. The discovery, distribution, structure property, enzymatic characteristics and recent researches in topical model organisms of ENGase were reviewed in this paper. Possible biological functions and mechanisms of ENGase, including differentiation, digestion of glycoproteins for nutrition and stress responding were hypothesised. In addition, the role of ENGase in glycan editing and synthetic biology was discussed. We hope this paper may provide insights for ENGase research and lay a solid foundation for applied and translational glycomics.

Protein as the allergens could lead to allergy. In addition, a widespread class of allergens were known as glycans of N-glycoprotein. N-glycoprotein contained oligosaccharide linked by covalent bonds with protein. Recently,studies implicated that allergy was associated with glycans of heterologous N-glycoprotein found in food, inhalants, insect toxins, etc. The N-glycan structure of N-glycoprotein allergen has exerted an influence on the binding between allergens and IgE, while the recognition and presentation of allergens by antigen-presenting cells (APCs) were also affected. Some researches showed thatN-glycan structure of allergen was remodeled by N-glycosidase, such as cFase I, gpcXylase, as binding of allergen and IgE partly decreased. Thus, allergic problems caused by N-glycoproteins could potentially be solved by modifying or altering the structure ofN-glycoprotein allergens, addressing the root of the issue. Mechanism of N-glycans associated allergy could also be elaborated through glycosylation enzymes, alterations of host glycosylation. This article hopes to provide a separate insight for glycoimmunology perspective, and an alternative strategy for clinical prevention or therapy of allergic diseases.

Patients with severe trauma require an extremely timely treatment and transfusion plays an irreplaceable role in the emergency treatment of such patients. An increasing number of evidence-based medicinal evidences and clinical practices suggest that patients with severe traumatic bleeding benefit from early transfusion of low-titer group O whole blood or hemostatic resuscitation with red blood cells, plasma and platelet of a balanced ratio. However, the current domestic mode of blood supply cannot fully meet the requirements of timely and effective blood transfusion for emergency treatment of patients with severe trauma in clinical practice. In order to solve the key problems in blood supply and blood transfusion strategies for emergency treatment of severe trauma, Branch of Clinical Transfusion Medicine of Chinese Medical Association, Group for Trauma Emergency Care and Multiple Injuries of Trauma Branch of Chinese Medical Association, Young Scholar Group of Disaster Medicine Branch of Chinese Medical Association organized domestic experts of blood transfusion medicine and trauma treatment to jointly formulate Chinese expert consensus on blood support mode and blood transfusion strategies for emergency treatment of severe trauma patients ( version 2024). Based on the evidence-based medical evidence and Delphi method of expert consultation and voting, 10 recommendations were put forward from two aspects of blood support mode and transfusion strategies, aiming to provide a reference for transfusion resuscitation in the emergency treatment of severe trauma and further improve the success rate of treatment of patients with severe trauma.

Silver nanoparticles(AgNPs)is widely used in biomedicine,daily chemicals,food industry and other fields,and the possible negative health effects of its exposure have attracted widespread attention.Accurate analysis of AgNPs in biological matrices is the basis for biosafety studies of AgNPs.Among the existing analytical techniques,single particle-inductively coupled plasma-mass spectrometry(sp-ICP-MS)has significant advantages such as high sensitivity and simultaneous detection of different forms of silver.However,AgNPs in biological matrices is uniquely highly dynamic and low in content,and the matrix interference is severe,which increases the complexity of the analysis.Although some scholars have reviewed the application of this method for detection of metal nanoparticles in different scenarios,there is a lack of a summary of the quality control and optimization of the whole process from the perspective of AgNPs detection.There is still a lack of reference standards for the sp-ICP-MS analysis of AgNPs in biological matrices,and the existing methods need to be summarized and further optimized to achieve accurate quantification.Therefore,this paper reviewed the recent studies on the analysis of silver-containing nanoparticles in biological matrices based on sp-ICP-MS,mainly included the principles of the technique,the extraction methods of the particles,and the process of data processing,which focused on elaborating and comparing different pre-treatment methods,and explored issues of the current application of sp-ICP-MS for detection of AgNPs in biological tissues and the development of future optimization trends.The current problems of sp-ICP-MS for detection of AgNPs in biological tissues and the future development trend were also discussed.

Abstract: Objective　To investigate the relationship between the body mass index (BMI) levels and the negative conversion time of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) nucleic acid in adult coronavirus disease 2019 (COVID-19) patients and the asymptomatic persons. Methods　Asymptomatic infected patients and confirmed COVID-19 patients admitted to Chengdu Public Health Clinic Center from February 2021 to November 2021 were dynamically included. The epidemiological and clinical characteristics of the objects were collected, and the SARS-CoV-2 nucleic acid testing of the objects during their hospitalization was continuously monitored, and the negative nucleic acid conversion time was recorded. The t test or Wilcoxon rank sum test, χ2 test or Fisher's exact probability method examine were used to distribute characteristics of each group of variables and the connection between different variables, respectively. Then the variables showed differences in distribution (P<0.05) between different BMI groups were included in the multivariate Cox proportional risk regression model. Results　A total of 253 subjects ranged from 18 to 63 years old, with M(P25, P75) age of 37.0 (30.0, 47.0) years old, were included in this study. The male to female ratio was 4.16 to 1. The BMI was (23.97±3.33) kg/m2. 50.59% (128/253) of the objects were overweight or obese, and 78.13% (100/128) were overweight. The negative time of SARS-CoV-2 nucleic acid conversion of all subjects ranged from 1 to 71 days, with M(P25, P75) of 7.0 (2.0, 18.0) days (P<0.001). The negative time of SARS-CoV-2 nucleic acid conversion of the normal weight or the thin, and the overweight or obese were 5.00 (2.00, 19.00) and 8.00 (2.00, 17.75) days respectively. The results of multivariate Cox's proportional hazards regression model showed that the BMI levels may not be associated with the negative conversion time of SARS-CoV-2 nucleic acid (HR=1.090, 95%CI: 0.843-1.410, P=0.510). Conclusions　Adult asymptomatic persons and confirmed COVID-19 patients are mainly middle-aged and young males, and overweight or obesity is relatively common. Overweight or obesity cannot be considered as an independent factor influencing the negative conversion time of SARS-CoV-2 nucleic acid.

This study aimed to investigate the therapeutic effect of Yunkang Oral Solution on the improvement of spleen deficiency and pregnancy outcomes in pregnant mice with spleen deficiency syndrome induced by irregular diet and over consumption of cold and bitter foods. To simulate human irregular diet and over consumption of cold and bitter foods leading to spleen deficiency, the pregnant mice with spleen deficiency syndrome were prepared using an alternate-day fasting and high-fat diet combined with oral administration of Sennae Folium. During the experiment, spleen deficiency-related indicators and diarrhea-related parameters were measured. Gastric and intestinal motility(gastric emptying rate and intestinal propulsion rate) were evaluated. The levels of serum ghrelin, growth hormone(GH), gastrin(Gas), total cholesterol(TC), low-density lipoprotein cholesterol(LDL-c), chorionic gonadotropin β(β-CG), progesterone(P), and estradiol(E_2) were measured. Intestinal barrier function in pregnant mice with spleen deficiency syndrome was assessed. Conception rate, ovarian coefficient, litter-bearing uterine coefficient, number of live fetuses, average fetal weight, and fetal length were calculated. The results showed that Yunkang Oral Solution significantly improved spleen deficiency-related indicators and diarrhea in pregnant mice with spleen deficiency syndrome, increased gastric emptying rate and intestinal propulsion rate, elevated the levels of gastrointestinal hormones(ghrelin, GH, and Gas) in the serum, and reduced lipid levels(TC and LDL-c), thereby improving lipid metabolism disorders. It also improved colonic tissue morphology, increased the number of goblet cells, and promoted the mRNA and protein expression of occludin and claudin-1 in colonic tissues, thereby alleviating intestinal barrier damage. Yunkang Oral Solution also regulated the levels of pregnancy hormones(β-CG, P, and E_2) in the serum of pregnant mice with spleen deficiency syndrome. Moreover, it increased the conception rate, ovarian coefficient, litter-bearing uterine coefficient, number of live fetuses, average fetal weight, and fetal length. These findings suggest that Yunkang Oral Solution can improve spleen deficiency-related symptoms in pregnant mice before and during pregnancy, regulate pregnancy-related hormones, and improve pregnancy outcomes.
Pregnancy ; Female ; Mice ; Humans ; Animals ; Spleen ; Ghrelin ; Fetal Weight ; Cholesterol, LDL ; Diarrhea

The aim of the present study was to investigate the effects of short-term ketogenic diet on the low temperature tolerance of mice and the involvement of peroxisome proliferator-activated receptor α (PPARα). C57BL/6J mice were divided into two groups: normal diet (WT+ND) group and ketogenic diet (WT+KD) group. After being fed with normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The changes in core temperature, blood glucose, blood pressure of mice under low temperature condition were detected, and the protein expression levels of PPARα and mitochondrial uncoupling protein 1 (UCP1) were detected by Western blot. PPARα knockout mice were divided into normal diet (PPARα^-/-+ND) group and ketogenic diet (PPARα^-/-+KD) group. After being fed with the normal or ketogenic diet at room temperature for 2 d, the mice were exposed to 4 °C low temperature for 12 h. The above indicators were also detected. The results showed that, at room temperature, the protein expression levels of PPARα and UCP1 in liver and brown adipose tissue of WT+KD group were significantly up-regulated, compared with those of WT+ND group. Under low temperature condition, compared with WT+ND, the core temperature and blood glucose of WT+KD group were increased, while mean arterial pressure was decreased; The ketogenic diet up-regulated PPARα protein expression in brown adipose tissue, as well as UCP1 protein expression in liver and brown adipose tissue of WT+KD group. Under low temperature condition, compared to WT+ND group, PPARα^-/-+ND group exhibited decreased core temperature and down-regulated PPARα and UCP1 protein expression levels in liver, skeletal muscle, white and brown adipose tissue. Compared to the PPARα^-/-+ND group, the PPARα^-/-+KD group exhibited decreased core temperature and did not show any difference in the protein expression of UCP1 in liver, skeletal muscle, white and brown adipose tissue. These results suggest that the ketogenic diet promotes UCP1 expression by up-regulating PPARα, thus improving low temperature tolerance of mice. Therefore, short-term ketogenic diet can be used as a potential intervention to improve the low temperature tolerance.
Animals ; Mice ; Adipose Tissue, Brown/metabolism* ; PPAR alpha/pharmacology* ; Diet, Ketogenic ; Uncoupling Protein 1/metabolism* ; Blood Glucose/metabolism* ; Temperature ; Mice, Inbred C57BL ; Liver ; Adipose Tissue/metabolism*

This study aims to evaluate the quality consistency of Saposhnikoviae Radix based on carbohydrates, and explore the potential of carbohydrates as the internal quality control indicators of Saposhnikoviae Radix. The total polysaccharides were quantified by UV-Vis spectrophotometry and the molecular weight range of the polysaccharides was determined by high performance gel-permeation chromatography-evaporative light scattering detection(HPGPC-ELSD). The monosaccharides in polysaccharides and the free monosaccharides were quantified by high performance liquid chromatography-UV detection(HPLC-UV), and the oligosaccharides and fructose were quantified by high performance liquid chromatography-evaporative light scattering detection(HPLC-ELSD). The carbohydrate-based quality of Saposhnikoviae Radix was compared among 45 batches of commercial samples and 13 batches of self-collected samples. The results showed that the molecular weight distribution, monosaccharide composition, oligosaccharide, and free monosaccharide composition were similar in the 58 batches of samples. The average content of total polysaccharides, oligosaccharides, and total free monosaccharides in commercial samples were 39.66, 148.79, and 68.62 mg·g~(-1), respectively. The content showed significant differences among batches, with the highest differences of 3.51, 1.75, and 2.58 times, respectively. The RSD of the relative ratios of monosaccharides in the polysaccharides in commercial samples reached 28%-45%. The average content of total polysaccharides, oligosaccharides, and total free monosaccharides in self-collected samples were 68.07, 145.76, and 42.04 mg·g~(-1), respectively, with the inter-region differences of 2.88, 1.88, and 1.07 times, respectively. The RSD of the relative ratios of monosaccharides in polysaccharides in self-collected samples ranged from 8.2% to 59%. The total polysaccharides and total free monosaccharides in self-collected samples were 1.72 times higher and 1.63 times lower, respectively, than those in commercial samples. The content of oligosaccharides was similar between self-collected samples and commercial samples. To sum up, carbohydrates are one of the material bases for the internal quality consistency of Saposhnikoviae Radix. The qualitative characteristics of polysaccharides and the quantitative characteristics of polysaccharides and oligosaccharides are related to the origin of medicinal materials. Moreover, the quantitative characteristics of polysaccharides and free monosaccharides may be related to the storage conditions. Carbohydrates are potential indicators for the quality control of Saposhnikoviae Radix and deserve attention.

Platelets are reprogrammed by cancer via a process called education, which favors cancer development. The transcriptional profile of tumor-educated platelets (TEPs) is skewed and therefore practicable for cancer detection. This intercontinental, hospital-based, diagnostic study included 761 treatment-naïve inpatients with histologically confirmed adnexal masses and 167 healthy controls from nine medical centers (China, n = 3; Netherlands, n = 5; Poland, n = 1) between September 2016 and May 2019. The main outcomes were the performance of TEPs and their combination with CA125 in two Chinese (VC1 and VC2) and the European (VC3) validation cohorts collectively and independently. Exploratory outcome was the value of TEPs in public pan-cancer platelet transcriptome datasets. The AUCs for TEPs in the combined validation cohort, VC1, VC2, and VC3 were 0.918 (95% CI 0.889-0.948), 0.923 (0.855-0.990), 0.918 (0.872-0.963), and 0.887 (0.813-0.960), respectively. Combination of TEPs and CA125 demonstrated an AUC of 0.922 (0.889-0.955) in the combined validation cohort; 0.955 (0.912-0.997) in VC1; 0.939 (0.901-0.977) in VC2; 0.917 (0.824-1.000) in VC3. For subgroup analysis, TEPs exhibited an AUC of 0.858, 0.859, and 0.920 to detect early-stage, borderline, non-epithelial diseases and 0.899 to discriminate ovarian cancer from endometriosis. TEPs had robustness, compatibility, and universality for preoperative diagnosis of ovarian cancer since it withstood validations in populations of different ethnicities, heterogeneous histological subtypes, and early-stage ovarian cancer. However, these observations warrant prospective validations in a larger population before clinical utilities.
Humans ; Female ; Blood Platelets/pathology* ; Biomarkers, Tumor/genetics* ; Ovarian Neoplasms/pathology* ; China

Objective: We analyze the characteristics of Clostridioides difficile (C. difficile) infection among diarrhea patients in Kunming from 2018 to 2020 and provide evidence for follow-up surveillance and prevention. Methods: A total of 388 fecal samples of diarrhea patients from four sentinel hospitals in Yunnan Province from 2018 to 2020 were collected. Real-time quantitative PCR was used to detect the fecal toxin genes of C. difficile. The positive fecal samples isolated the bacteria, and isolates were identified by mass spectrometry. The genomic DNA of the strains was extracted for multi-locus sequence typing (MLST). The fecal toxin, strain isolation, and clinical patient characteristics, including co-infection with other pathogens, were analyzed. Results: Among the 388 fecal samples, 47 samples with positive reference genes of C. difficile were positive, with a total positive rate of 12.11%. There were 4 (8.51%) non-toxigenic and 43 (91.49%) toxigenic ones. A total of 18 strains C. difficile were isolated from 47 positive specimens, and the isolation rate of positive specimens was 38.30%. Among them, 14 strains were positive for tcdA, tcdB, tcdC, tcdR, and tcdE. All 18 strains of C. difficile were negative for binary toxins. The MLST results showed 10 sequence types (ST), including 5 strains of ST37, accounting for 27.78%; 2 strains of ST129, ST3, ST54, and ST2, respectively; and 1 strain of ST35, ST532, ST48, ST27, and ST39, respectively. Fecal toxin gene positive (tcdB+) results were statistically associated with the patient's age group and with or without fever before the visit; positive isolates were only statistically associated with the patient's age group. In addition, some C. difficile patients have co-infection with other diarrhea-related viruses. Conclusions: The infection of C. difficile in diarrhea patients in Kunming is mostly toxigenic strains, and the high diversity of strains was identified using the MLST method. Therefore, the surveillance and prevention of C. difficile should be strengthened.
Humans ; Bacterial Toxins/genetics* ; Enterotoxins/genetics* ; Clostridioides difficile/genetics* ; Multilocus Sequence Typing ; Coinfection ; Bacterial Proteins/genetics* ; China/epidemiology* ; Clostridium Infections/epidemiology* ; Diarrhea/microbiology*