Objective: To establish an ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method based on solid-phase extraction column purification for simultaneous determination of cyromazine and melamine in poultry eggs and meat. Methods: Eggs, quail eggs, and chicken were collected from markets. After homogenization, the sample was extracted with 0.5% formic acid in acetonitrile, subjected to solid-phase extraction using an MCX cartridge, and eluted with 5% ammonia in methanol. The eluate was collected, evaporated to near dryness under nitrogen, and reconstituted in a 10% aqueous methanol solution. Separated using TSK gel Amide-80 column (2.0 mm×150 mm, 5 μm), cyromazine and melamine were simultaneously detected in positive ion multiple reaction monitoring mode via tandem mass spectrometry, with quantification achieved by isotope dilution internal standard methods. Efficiency was enhanced and matrix interference minimized by optimizing conditions such as sample extraction, solid-phase extraction cartridge selection, and instrumental parameters. Calibration curves were constructed, and detection limits, quantification limits, spiked recoveries, and relative standard deviations for (RSD) of cyromazine and melamine were calculated. Results: After method optimization, matrix effects for cyromazine and melamine ranged from 0.97 to 1.04, indicating no significant matrix suppression or enhancement. Both cyromazine and melamine exhibited excellent linearity within the concentration range of 1.0-200.0 ng/mL, with correlation coefficients ≥0.999 5. The limits of detection were 0.3 μg/kg for cyromazine and 0.5 μg/kg for melamine, the quantification limits were 1.0 and 1.5 μg/kg, respectively. At spiked levels of 1.0, 20.0, and 150.0 μg/kg, the average recoveries ranged from 78.6% to 103.1%, with RSD between 3.5% and 6.3%. Among 95 samples tested, cyromazine was detected in 6 samples and melamine in 5 samples; neither cyromazine nor melamine was detected in chicken samples. Conclusion The UPLC-MS/MS method established in this study enables simultaneous detection and accurate quantification of cyromazine and melamine in poultry eggs and meat.

In order to investigate the regulatory effect of Codonopsis saponins on the immunosup-pression caused by H9N2 subtype avian influenza virus(AIV)infection,rat pulmonary microvas-cular endothelial cells(RPMECs)were incubated with different concentrations of Codonopsis sap-onins(5,10 and 20 mg/L).The expression level of PD-L1 was detected by RT-PCR and flow cy-tometry,and the contents of TNF-α,IFN-y and IL-10 in supernatant were detected by ELISA kit.The titer of H9N2 AIV in supernatant was detected by plaque method.Then,a co-culture system of RPMECs and T cells was established using a Transwell plate with an aperture of 8 μm to mimic the migration of circulating T cells across microvessels to the site of viral infection.RPMECs were cultured in the upper chamber of Transwell,inoculated with H9N2 AIV,supplemented with 20 mg/L Codonopsis saponins 1 h later,and T cells 36 h later.After 8 h of treatment,T cells in the lower compartment were collected and the proportions of CD4+T cells and CD8+T cells were detected by flow cytometry,the expression levels of IL-2,IFN-y and granzyme B in the superna-tant were detected by ELISA,and the proportions of perforin-1 positive T cells were detected by flow cytometry.The proliferation activity of T cells was detected with the MTT cell proliferation and cytotoxicity assay kit,and the percentage of apoptotic cells was detected by flow cytometry af-ter staining of T cells with Annexin V-FITC/PI.The experimental results showed that Codonopsis saponins could significantly reduce the expression level of PD-L1,IL-10 and TNF-α in RPMECs in-duced by H9N2 AIV infection,and reduce the apoptosis rate of T cells.However,the expression levels of IL-2,IFN-y,perforin-1 and granzyme B in transendothelial migration T cells and the pro-liferation activity of T cells were significantly increased.In this study,Codonopsis saponins can sig-nificantly inhibit the expression of H9N2 AIV-induced PD-L1 in RPMECs,enhance the antiviral function of T cells migrating across the endothelial layer,and enhance the resistance of host to H9N2 AIV.

Objective:To investigate the effectiveness and safety of domestic upper gastrointestinal endoscopic ultrasound (EUS).Methods:A total of 160 patients undergoing EUS at Shengjing Hospital of China Medical University (Center1) and Shenzhen People's Hospital (Center 2) from March to July 2021 were randomly selected by stratified blocked randomization, and were treated with SonoScape EG-UG5T (the test group) or Fujifilm EG-580UT (the control group). The primary outcome was the ultrasound image quality excellence rate, and the comparison was verified by non-inferiority. The secondary outcomes were the endoscopic image quality excellence rate, the operational performance excellence rate, and the system stability evaluation. The safety evaluation was based on the occurrence of intraoperative and postoperative adverse events in the subjects.Results:In the intention-to-treat analysis set (ITT), the excellence rate of ultrasound image quality in the test group and the control group was 100.0% (78/78) and 100.0% (77/77), respectively. The rate difference between the two groups was 0.0% (95% CI: -4.7%-4.8%). In the per protocol analysis set (PPS), the excellence rate of ultrasound image quality in the test group and the control group was 100.0% (78/78) and 100.0% (75/75), respectively. The rate difference between the two groups was 0.0% (95% CI: -4.7%-4.9%). The lower limit of the confidence interval of ultrasound image quality excellence rate of both data sets was greater than the non-inferiority threshold value of -8%, which inferred that the non-inferiority hypothesis of the test machine non-inferior to the control machine was valid. The endoscopic image quality excellence rate and the operational performance excellence rate of the test group and the control group was 100.0% in both the ITT and PPS analyses, and there was no statistically significant difference between the two groups ( P=1.000). The system instability event rate was 0.0% (0/78) in the test group and 3.9% (3/77) in the control group ( P=0.120). No adverse event occurred in either group. Conclusion:The domestic upper gastrointestinal endoscopic ultrasound is standard-compliant for clinical application under normal conditions in terms of effectiveness, safety, and stability.

  Objective  To investigate the needs of eight-year program clinical medical students for the organization and contents of clinical oncology courses.  Methods  From September to November 2020, a questionnaire survey was conducted among eight-year program clinical medicine students in Peking Union Medical College to find out their knowledge base in oncology, teaching mode preference and course contents of interest.  Results  A total of 122 students participated in the survey, in which 89.3%(109/122) of the students showed interest in basic and clinical research projects related to oncology, 84.4%(103/122) thought it was better to use Simulation-based medical education (SBME), and 91.0%(111/122) hoped to learn throughoff-line discussion. In terms of course contents, eight-year program medical students were more interested in knowledge directly related to clinical context, such as diagnosis, treatment, multidisciplinary comprehensive treatment and evidence-based medicine. In terms of sub-analysis, traditional eight-year students (86%, 92/107) showed a higher acceptance of palliative care than students in the 4+4 reform program(60%, 9/15) and were more willing to act as scriptwriters in SBME(26% vs. 7%, P=0.013). The students in clinical phase gained a better understanding of oncology knowledge through research training and were more inclined to take on the role of scriptwriters in SBME than those in basic phase (27% vs. 11%, P=0.048).  Conclusions  The eight-year program clinical medical students are interested in the clinical oncology course and prefer study in the form of Simulation-based medical education (SBME).

To address the key challenges in multivariate statistical modeling,a higher-order derivative approach combined with vector space angle multiplicative error correction was proposed for establishing an acid value prediction ordinary least squares(OLS)regression model based on attenuated total reflectance-Fourier transform infrared(ATR-FTIR)spectroscopy.By using acid values measured by potentiometric titration as reference,ATR-FTIR spectroscopy was utilized for direct calibration and prediction of acid values on 96 kinds of lubricating oil samples from a wind turbine.Firstly,the simulated hyperbolic(SH)method was employed to obtain accurate fourth derivative spectrum,resolving overlapping bands and enhancing spectral selectivity.Then,from the calibration set(48 samples),informative spectral regions were identified based on correlation coefficients.Next,the sample with the highest acid value was selected as the reference and1/(1+tan(θ/2))was used as the metric relation of the spectrum to suppress the multiplicity error caused by factors such as the change of effective optical path in ATR-FTIR spectroscopy.After pretreatment of the spectrum by the method of fourth-order derivative combined with angular quantity,the number of variables decreased from 1737 to 8,and the matrix condition number decreased from 1.85×1015 to 56.34,which effectively eliminated the collinearity issue for OLS regression.Direct OLS modeling on spectral preprocessed data achieved a determination coefficient of 0.981 for 47 validation samples,with a relative error range of-8.38%-8.22%,outperforming the commonly used partial least squares(PLS)method(Determination coefficient of 0.865,relative error of-27.82%-22.38%).It was proved that effective data preprocessing significantly improved the prediction accuracy of the model.Furthermore,when the number of calibration set was compressed to 25 and the number of validation set was expanded to 70,the model retained 8 variables with a condition number of 42.60,the determination coefficient of validation set was 0.972,and the relative error ranged from-10.80%to 12.31%.Comparing with the PLS method(Determination coefficient of 0.724,relative error of-34.26%-53.84%),the improvement was more obvious,which showed that the method could still have high prediction accuracy even with fewer modeling samples as well as robustness against multiplicative error interference.

Pancreatic cancer is a highly malignant tumor with a poor prognosis. It is very hard to treat pancreatic cancers for their high heterogeneity, complex tumor microenvironment, and drug resistance. Currently, gemcitabine plus nab-paclitaxel, capecitabine and FOLFIRINOX are standard chemotherapy for resectable or advanced metastatic pancreatic cancer. Considering the limited efficacy and toxic side effects of chemotherapy, targeted and immune drugs have gradually attracted attention and made some progress. In this article, we systematically reviewed the chemotherapeutic drugs, targets and related targeted drugs, and immunotherapy drugs for pancreatic cancer.

Objective:To assess the clinical effectiveness and safety of Omalizumab for treating pediatric allergic asthma in real world in China.Methods:The clinical data of children aged 6 to 11 years with allergic asthma who received Omalizumab treatment in 17 hospitals in China between July 6, 2018 and September 30, 2020 were retrospectively analyzed.Such information as the demographic characteristics, allergic history, family history, total immunoglobulin E (IgE) levels, specific IgE levels, skin prick test, exhaled nitric oxide (FeNO) levels, eosinophil (EOS) counts, and comorbidities at baseline were collected.Descriptive analysis of the Omalizumab treatment mode was made, and the difference in the first dose, injection frequency and course of treatment between the Omalizumab treatment mode and the mode recommended in the instruction was investigated.Global Evaluation of Treatment Effectiveness (GETE) analysis was made after Omalizumab treatment.The moderate-to-severe asthma exacerbation rate, inhaled corticosteroid (ICS) dose, lung functions were compared before and after Omalizumab treatment.Changes in the Childhood Asthma Control Test (C-ACT) and Pediatric Asthma Quality of Life Questionnaire (PAQLQ) results from baseline to 4, 8, 12, 16, 24, and 52 weeks after Omalizumab treatment were studied.The commodity improvement was assessed.The adverse event (AE) and serious adverse event (SAE) were analyzed for the evaluation of Omalizumab treatment safety.The difference in the annual rate of moderate-to-severe asthma exacerbation and ICS reduction was investigated by using t test.The significance level was set to 0.05.Other parameters were all subject to descriptive analysis.A total of 200 allergic asthma patients were enrolled, including 75.5% ( n=151) males and 24.5% ( n=49) females.The patients aged (8.20±1.81) years. Results:The median total IgE level of the 200 patients was 513.5 (24.4-11 600.0) IU/mL.Their median treatment time with Omalizumab was 112 (1-666) days.Their first dose of Omalizumab was 300 (150-600) mg.Of the 200 cases, 114 cases (57.0%) followed the first Omalizumab dosage recommended in the instruction.After 4-6 months of Omalizumab treatment, 88.5% of the patients enrolled ( n=117) responded to Omalizumab.After 4 weeks of treatment with Omalizumab, asthma was well-controlled, with an increased C-ACT score [from (22.70±3.70) points to (18.90±3.74) points at baseline]. Four-six months after Omalizumab administration, the annual rate of moderate-to-severe asthma exacerbation had a reduction of (2.00±5.68) per patient year( t=4.702 5, P<0.001), the median ICS daily dose was lowered [0 (0-240) μg vs. 160 (50-4 000) μg at baseline] ( P<0.001), the PAQLQ score was improved [(154.90±8.57) points vs. (122.80±27.15) points at baseline], and the forced expiratory volume in one second % predicted (FEV 1%pred) was increased [(92.80±10.50)% vs. (89.70±18.17)% at baseline]. In patients with available evaluations for comorbidities, including allergic rhinitis, atopic dermatitis or eczema, urticaria, allergic conjunctivitis and sinusitis, 92.8%-100.0% showed improved symptoms.A total of 124 AE were reported in 58 (29.0%) of the 200 patients, and the annual incidence was 0(0-15.1) per patient year.In 53 patients who suffered AE, 44 patients (83.0%) and 9 patients (17.0%) reported mild and moderate AE, respectively.No severe AE were observed in patients.The annual incidence of SAE was 0(0-1.9) per patient year.Most common drug-related AE were abdominal pain (2 patients, 1.0%) and fever (2 patients, 1.0%). No patient withdrew Omalizumab due to AE. Conclusions:Omalizumab shows good effectiveness and safety for the treatment of asthma in children.It can reduce the moderate-to-severe asthma exacerbation rate, reduce the ICS dose, improve asthma control levels, and improve lung functions and quality of life of patients.

Objective:To explore the difference of lymphocyte subsets in peripheral blood(PB)between aplastic anemia(AA)and hypoplastic myelodysplastic syndrome(hypo-MDS)patients,meanwhile to compare the clinical parameters obtained from PB and bone marrow(BM).Methods:The lymphocyte subsets in hypo-MDS(n=25)and AA(n=33)patients were investigated by flow cytometry.Meanwhile,the differences in PB cell counts,biochemical indicators,BM cell counts and abnormal chromosomes between the two groups were analyzed.Results:The percentage of CD8+T cells in A A group was significantly higher than that in hypo-MDS group(P=0.001),while the percentage of CD4+T cells and the CD4+/CD8+ratio in AA group were obviously lower than those in hypo-MDS group(P=0.015 and0.001,respectively).Furthermore,the proportion of CD4+andCD8+activated T(TA)cells,and memory Tregs in AA group was distinctly lower than those in hypo-MDS group(P=0.043,0.015 and 0.024,respectively).Nevertheless,the percentage of CD8+naive T(TN)cells in AA patients was remarkably higher(P=0.044).And hypo-MDS patients had declined lymphocyte counts(P=0.025),increased levels of total bilirubin(TBil),lactate dehydrogenase(LDH),vitamin B12 and proportion of BM blasts than AA patients(P=0.019,0.023,0.027 and 0.045,respectively).Conclusion:In this study it was confirmed that the percentages of CD4+and CD8+TA cells,memory Tregs and CD8+TN cells were significantly different between AA and hypo-MDS patients,which provide an essential basis for the identification of these two diseases.

Humans ; Child ; Neurofibromatosis 1/drug therapy* ; Benzimidazoles/therapeutic use*

To understand how the nervous system develops from a small pool of progenitors during early embryonic development, it is fundamentally important to identify the diversity of neuronal subtypes, decode the origin of neuronal diversity, and uncover the principles governing neuronal specification across different regions. Recent single-cell analyses have systematically identified neuronal diversity at unprecedented scale and speed, leaving the deconstruction of spatiotemporal mechanisms for generating neuronal diversity an imperative and paramount challenge. In this review, we highlight three distinct strategies deployed by neural progenitors to produce diverse neuronal subtypes, including predetermined, stochastic, and cascade diversifying models, and elaborate how these strategies are implemented in distinct regions such as the neocortex, spinal cord, retina, and hypothalamus. Importantly, the identity of neural progenitors is defined by their spatial position and temporal patterning factors, and each type of progenitor cell gives rise to distinguishable cohorts of neuronal subtypes. Microenvironmental cues, spontaneous activity, and connectional pattern further reshape and diversify the fate of unspecialized neurons in particular regions. The illumination of how neuronal diversity is generated will pave the way for producing specific brain organoids to model human disease and desired neuronal subtypes for cell therapy, as well as understanding the organization of functional neural circuits and the evolution of the nervous system.
Humans ; Neural Stem Cells/physiology* ; Neurons/physiology* ; Brain ; Spinal Cord ; Embryonic Development ; Cell Differentiation/physiology*