[Objective] To study the molecular biological mechanism for a case of ABO blood group B subtype, and perform three-dimensional modeling of the mutant enzyme. [Methods] The ABO phenotype was identified by the tube method and microcolumn gel method; the ABO gene of the proband was detected by sequence-specific primer polymerase chain reaction (PCR-SSP), and the exon 6 and 7 of the ABO gene were sequenced and analyzed. Homologous modeling of Bw.03 glycosyltransferase (GT) was carried out by Modeller and analyzed by PyMOL2.5.0 software. [Results] The weakening B antigen was detected in the proband sample by forward typing, and anti-B antibody was detected by reverse typing. PCR-SSP detection showed B, O gene, and the sequencing results showed c.721 C>T mutation in exon 7 of the B gene, resulting in p. Arg 241 Trp. Compared with the wild type, the structure of Bw.03GT was partially changed, and the intermolecular force analysis showed that the original three hydrogen bonds at 241 position disappeared. [Conclusion] Blood group molecular biology examination is helpful for the accurate identification of ambiguous blood group. Homologous modeling more intuitively shows the key site for the weakening of Bw.03 GT activity. The intermolecular force analysis can explain the root cause of enzyme activity weakening.

Mesenchymal stem cells (MSCs) have been widely used in the treatment of various autoimmune and inflammation-related diseases due to their potent immunomodulatory properties. Several studies have demonstrated that MSC-mediated immunomodulation is complex and bidirectional, with the in vivo microenvironment influencing the direction of this modulation. Indoleamine-2,3-dioxygenase (IDO), an immunosuppressive factor, has been identified as a key "switch" in the immunomodulatory role of MSCs. In this review, we explore how IDO functions as a critical regulator of MSC immunoregulatory plasticity. We delve into the mechanisms by which changes in IDO expression affect the function of various immune cells, summarize relevant research and clinical advances regarding the role of IDO expression in MSC-based therapies for various diseases, and discuss potential therapeutic strategies that target IDO to enhance the stability of MSC therapeutic effects. This provides a theoretical foundation for optimizing MSCs as safer and more effective clinical therapeutic agents.

Objective Previous studies on the association between lipid profiles and chronic kidney disease(CKD)have yielded inconsistent results and no defined thresholds for blood lipids. Methods A prospective cohort study including 32,351 subjects who completed baseline and follow-up surveys over 5 years was conducted.Restricted cubic splines and Cox models were used to examine the association between the lipid profiles and CKD.A regression discontinuity design was used to determine the cutoff value of lipid profiles that was significantly associated with increased the risk of CKD. Results Over a median follow-up time of 2.2(0.5,4.2)years,648(2.00%)subjects developed CKD.The lipid profiles that were significantly and linearly related to CKD included total cholesterol(TC),triglycerides(TG),high-density lipoprotein cholesterol(HDL-C),TC/HDL-C,and TG/HDL-C,whereas low-density lipoprotein cholesterol(LDL-C)and LDL-C/HDL-C were nonlinearly correlated with CKD.TC,TG,TC/HDL-C,and TG/HDL-C showed an upward jump at the cutoff value,increasing the risk of CKD by 0.90%,1.50%,2.30%,and 1.60%,respectively,whereas HDL-C showed a downward jump at the cutoff value,reducing this risk by 1.0%.Female and participants with dyslipidemia had a higher risk of CKD,while the cutoff values for the different characteristics of the population were different. Conclusion There was a significant association between lipid profiles and CKD in a prospective cohort from Northwest China,while TG,TC/HDL-C,and TG/HDL-C showed a stronger risk association.The specific cutoff values of lipid profiles may provide a clinical reference for screening or diagnosing CKD risk.

Humans ; Aged ; Lung Diseases ; Pneumonia/drug therapy* ; Adrenal Cortex Hormones/therapeutic use* ; Pulmonary Disease, Chronic Obstructive/drug therapy* ; Administration, Inhalation ; Community-Acquired Infections/drug therapy*

Nitroxide radicals are a kind of stable organic free radicals.Due to the presence of N-O·and unpaired electrons in its structure,it has many characteristics,and thus can be used as a spin marker to explore the mechanism of biological reactions;with its magnetic properties,it can be used for the development of multifunctional magnetic molecular materials and used as a polymerization inhibitor and catalyst in organic reactions.More importantly,it has a variety of biological activities such as anti-oxidation and anti-tumor,and so has attracted much attention in the research and development of new drugs.For example,the spin labeling of nitroxide radicals on anticancer drug podophyllotoxin can enhance the efficacy and reduce the toxicity,and can be easily to be absorbed by the body,thus obtaining a new anti-cancer drug 4-[4″-(2″,2″,6″,6″-tetramethyl-1″-piperidinyloxy nitroxide radical)amino]-4′-demethyl epipodophyllotoxin(GP-7).It is an effective way to seek new drugs by introducing pharmacophore to modify nitroxide radicals or it can be spin-labeled on active natural products to obtain new compounds with high efficiency and low toxicity.The research progress of derivatives and its biological activitives of nitroxide radicals are summarized,aiming to provide theoretical basis for the developing and utilizing of nitroxide radicals and searching for new drugs.

An innovative on-site real-time avian influenza virus(AIV)detection method was estab-lished by integratingrecombinase-aided amplification(RAA)with the clustered regularly inter-spaced short palindromic repeats(CRISPR)/CRISPR-associated protein(Cas)system.After analy-zing 120 sequences of the M gene of avian influenza viruses of different subtypes publicly available on NCBI,the RAA primers and crRNA were designed based on the identified highly conserved segment and used for RAA nucleic acid amplification.After the amplified products were transferred to a CRISPR/Cas13a detection system,the fluorescence values were monitored throughout the re-action process to indicate the results.The sensitivity and specificity of the RAA-CRISPR/Cas13a method were validated using gradient dilutions(106-100 copies/μL)of positive plasmids and sev-en other avian viruses.Fifty clinical samples were tested using this method and compared with the national standard fluorescence RT-PCR method.The results indicated that the detection limit for RAA-CRISPR/Cas13a method was 102 copies/μL,a two-fold improvement over the standard RAA.Specificity assay showed the established method only detected AIV with no cross-reactivity with other seven avian viruses.Compared to the national standard fluorescence RT-PCR method,this method exhibited 100％specificity,95.24％accuracy,and 98.00％consistency in detection of clinical samples.In conclusion,a universal and rapid RAA-CRISPR/Cas13a for detection of AIV was established with the capacity of achieving detection within 60 minutes at 37 ℃,which provides a rapid,sensitive,and specific on-site detection method for AIV.

Objectives:To observe the exercise tolerance and cardiopulmonary function characteristics of patients with obstructive sleep apnea-hypopnea syndrome (OSAHS) combined with cardiovascular disease,in order to assess the cardiorespiratory reserve and health status of untreated OSAHS,and to provide a clinical evidence for the phase Ⅱ cardiac rehabilitation. Methods:This retrospective analysis included 134 cardiovascular disease patients who attended the Cardiac Rehabilitation Center of Fuwai Hospital,Chinese Academy of Medical Sciences from November 2021 to April 2024 and received home sleep apnea monitoring (HSAT).According to the apnea hypopnea index (AHI),the patients were divided into the non-OSAHS (AHI<5 times/h) group (n=24),the mild-OSAHS (5 times/h ≤AHI<15 times/h) group (n=65),and moderate-to-severe OSAHS (AHI ≥15 times/h) group (n=45),and the body composition,pulmonary function characteristics,exercise tolerance,and ventilatory response to exercise were compared among the three groups. Results:A total of 110 (82.1％) patients had comorbid OSAHS,with a higher proportion of male patients (80.0％).Height,weight,body mass index,lean body mass,skeletal muscle mass,body water content,and basal metabolic rate increased progressively with increasing OSAHS severity in three groups (all P<0.05),while cardiovascular disease comorbidity was similar.Static lung function,exercise tolerance and ventilatory function at maximal exercise were similar between the patients in the mild OSAHS group and the moderate-severe OSAHS group as compared to the non-OSAHS group (all P>0.05).With the increase in the severity of OSAHS,the cardiorespiratory fitness showed a decreasing trend among patients in the three groups,and the forced vital capacity and the maximum vital capacity of patients in the moderate-severe OSAHS group were significantly higher than that of the mild OSAHS group,while peak O2 pulse％pred was significantly lower than that of the mild OSAHS group (all P<0.05).Multivariate analysis showed that the body fat mass (β=0.307,95％CI:0.263-0.823,P<0.001),minute ventilation at rest (β=0.259,95％CI:0.429-1.785,P=0.002) were the independent influencing factors of AHI. Conclusions:The prevalence of OSAHS is high in patients with cardiovascular disease,and patients with moderate-to-severe OSAHS have reduced cardiorespiratory fitness,OSAHS is not associated with additional cardiac impairment and ventilatory function impairment in patients with cardiovascular disease.Weight loss should be the primary rehabilitation goal in patients with OSAHS combined with cardiovascular disease.

Objective:To study the molecular basis for a proband with A subtype B of the ABO blood group and explore the influence of amino acid variant on the activity of glycosyltransferase (GT).Methods:A proband who had presented at the First Affiliated Hospital of Zhengzhou University on July 2, 2020 was selected as the study subject. Serological identification of the ABO blood groups of the proband and her family members were performed by gel card and test tube methods. The ABO gene of the proband was identified by PCR-sequence specific primers (PCR-SSP) and DNA sequencing. A 3D molecular homologous model was constructed to predict the impact of the variant on the stability of α-(1→3)-D-N-acetylgalactosamine transferase (GTA). Results:The red blood cells of the proband, her mother and two younger brothers showed weak agglutination with anti-A and strong agglutination with anti-B. The sera showed 1~2+ agglutination with Ac and no agglutination with Bc. Based on the serological characteristics, the proband was identified as AwB subtype. Pedigree analysis suggested that the variant was inherited from her mother. The blood group of the proband was identified as A223B type by PCR-SSP. ABO gene sequencing analysis showed that the proband has harbored heterozygous variants of c. 297A>G, c. 467C>T, c. 526C>G, c. 657C>T, c. 703G>A, c. 796C>A, c. 803G>C, c. 930G>A and c. 1055insA. Based on the results of clone sequencing, it was speculated that the genotype was ABO* A223/ ABO* B.01. There were c. 467C>T and c. 1055insA variants compared with ABO* A1.01, and c. 1055insA variant compared with ABO* A1.02. Homologous modeling showed that the C-terminal of A223 GT was significantly prolonged, and the local amino acids and hydrogen bond network have changed. Conclusion:Above results revealed the molecular genetics mechanism of A223B subtype. The c. 1055insA variant carried by the proband may affect the enzymatic activity of GTA and ultimately lead to weakening of A antigen.

Objective To investigate the clinical value of matrix-assisted laser desorption/ionization time of flight mass spectrometry(MALDI-TOF MS)in rapid detection of carbapenemase produced by Klebsiella pneumoniae and Pseudomonas aeruginosa.Methods A total of 60 strains of Klebsiella pneumoniae and 80 strains of Pseudomonas aeruginosa isolated from Pizhou People's Hospital affiliated to Xuzhou Medical University from January 2022 to October 2023 were collected,including 30 strains of carbapenem-resistant Klebsiella pneumoniae(CRKP),30 strains of carbapenem-sensitive Klebsiella pneumoniae(CSKP),50 strains of carbapenem-resistant Pseudo-monas aeruginosa(CRPA)and 30 strains of carbapenem-sensitive Pseudomonas aeruginosa(CSPA).Three detection methods were applied,i.e.,modified carbapenem inactivation method(mCIM),colloidal gold immunochromatography and Autof MS 1000 mass spectrometry identification system to evaluate the ability of Autof MS 1000 mass spectrometry identification system in detecting carbape-nase production of Klebsiella pneumoniae and Pseudomonas aeruginosa.Results The results of Autof MS 1000 mass spectrometry iden-tification system were consistent with those of both mCIM and colloidal gold immunochromatography.Carbapenemase was detected in 28 of the 30 CRKP strains,and it was negative in 2 CRKP strains.Carbapenamase was detected in 15 of the 50 CRPA strains and it was negative in 35 CRPA strains.Thirty strains of CSKP and 30 strains of CSPA were all Carbapenemase negative.The coincidence rate of the results of the three methods in the detection for carbapenase was 100％.Conclusion The result of Autof MS 1000 mass spectrome-try identification system has been consistent with those of mCIM and colloidal gold immunochromatography.It not only has the charac-teristics of cost-saving compare with of mCIM method,but also hold the advantages of fast speed and high accuracy of colloidal gold im-munochromatography method.Thus,Autof MS 1000 system can be used for the rapid identification of carbapenemase produced by Kleb-siella pneumoniae and Pseudomonas aeruginosa.

Objective:To evaluate the diagnostic efficacy and practicality of the Jaundice color card (JCard) as a screening tool for neonatal jaundice.Methods:Following the standards for reporting of diagnostic accuracy studies (STARD) statement, a multicenter prospective study was conducted in 9 hospitals in China from October 2019 to September 2021. A total of 845 newborns who were admitted to the hospital or outpatient department for liver function testing due to their own diseases. The inclusion criteria were a gestational age of ≥35 weeks, a birth weight of ≥2 000 g, and an age of ≤28 days. The neonate′s parents used the JCard to measure jaundice at the neonate′s cheek. Within 2 hours of the JCard measurement, transcutaneous bilirubin (TcB) was measured with a JH20-1B device and total serum bilirubin (TSB) was detected. The Pearson′s correlation analysis, Bland-Altman plots and the receiver operating characteristic (ROC) curve were used for statistic analysis.Results:Out of the 854 newborns, 445 were male and 409 were female; 46 were born at 35-36 weeks of gestational age and 808 were born at ≥37 weeks of gestational age. Additionally, 432 cases were aged 0-3 days, 236 cases were aged 4-7 days, and 186 cases were aged 8-28 days. The TSB level was (227.4±89.6) μmol/L, with a range of 23.7-717.0 μmol/L. The JCard level was (221.4±77.0) μmol/L and the TcB level was (252.5±76.0) μmol/L. Both the JCard and TcB values showed good correlation ( r=0.77 and 0.80, respectively) and agreements (96.0% (820/854) and 95.2% (813/854) of samples fell within the 95% limits of agreement, respectively) with TSB. The JCard value of 12 had a sensitivity of 0.93 and specificity of 0.75 for identifying a TSB ≥205.2?μmol/L, and a sensitivity of 1.00 and specificity of 0.35 for identifying a TSB ≥342.0?μmol/L. The TcB value of 205.2?μmol/L had a sensitivity of 0.97 and specificity of 0.60 for identifying TSB levels of 205.2 μmol/L, and a sensitivity of 1.00 and specificity of 0.26 for identifying TSB levels of 342.0 μmol/L. The areas under the ROC curve (AUC) of JCard for identifying TSB levels of 153.9, 205.2, 256.5, and 342.0 μmol/L were 0.96, 0.92, 0.83, and 0.83, respectively. The AUC of TcB were 0.94, 0.91, 0.86, and 0.87, respectively. There were both no significant differences between the AUC of JCard and TcB in identifying TSB levels of 153.9 and 205.2 μmol/L (both P>0.05). However, the AUC of JCard were both lower than those of TcB in identifying TSB levels of 256.5 and 342.0 μmol/L (both P<0.05). Conclusions:JCard can be used to classify different levels of bilirubin, but its diagnostic efficacy decreases with increasing bilirubin levels. When TSB level are ≤205.2 μmol/L, its diagnostic efficacy is equivalent to that of the JH20-1B. To prevent the misdiagnosis of severe jaundice, it is recommended that parents use a low JCard score, such as 12, to identify severe hyperbilirubinemia (TSB ≥342.0 μmol/L).