Folic acid is a fully oxidized synthetic folate with high bioavailability and stability which has been extensively prescribed to prevent congenital disabilities. Here we revealed the immunosuppressive effect of folic acid by targeting splenic marginal zone B (MZB) cells. Folic acid demonstrates avid binding with the Fc domain of immunoglobulin M (IgM), targeting IgM positive MZB cells in vivo to destabilize IgM-B cell receptor (BCR) complex and block immune responses. The induced anergy of MZB cells by folic acid provides an immunological escaping window for antigens. Covalent conjugation of folic acid with therapeutic proteins and antibodies induces immunological evasion to mitigate the production of anti-drug antibodies, which is a major obstacle to the long-term treatment of biologics by reducing curative effects and/or causing adverse reactions. Folic acid acts as a safe and effective immunosuppressant via IgM-mediated MZB cells targeting to boost the clinical outcomes of biologics by inhibiting the production of anti-drug antibodies, and also holds the potential to treat other indications that adverse immune responses need to be transiently shut off.

Objective:To explore the application value of dynamic monitoring of gastric residual volume (GRV) in achieving different target energy in severe mechanical ventilation patients.Methods:A prospective randomized controlled study was conducted. Forty-two patients with mechanical ventilation admitted to the department of critical care medicine of General Hospital of Ningxia Medical University from July to December 2022 were enrolled. According to the random number table method, patients were divided into GRV guided enteral nutrition by traditional gastric juice pumpback method (control group, 22 patients) and GRV guided enteral nutrition by bedside ultrasound (test group, 20 patients). General data were collected from both groups, and clinical indicators such as hypersensitive C-reactive protein (hs-CRP), interleukin-6 (IL-6), neutrophil percentage (Neut%), procalcitonin (PCT), absolute lymphocytes (LYM), prealbumin (PA), and retinol-binding protein (RBP) were dynamically observed. Inflammation, infection, immunity, nutritional indicators, and the incidence of reflux/aspiration, ventilator-associated pneumonia (VAP) were compared between the two groups, and further compared the proportion of patients with respectively to reach the target energy 25%, 50%, and 70% on days 1, 3, and 5 of initiated enteral nutrition.Results:① There were no significant differences in gender, age, body mass index (BMI), duration of mechanical ventilation, and acute physiology and chronic health evaluationⅡ(APACHEⅡ), sequential organ failure assessment (SOFA), severe nutritional risk score (NUTRIC) at admission between the two groups, indicating comparability. ② On day 1 of initiated enteral nutrition, there were no significant differences in infection, inflammation, immunity and nutrition indicators between the two groups. On day 3 of initiated enteral nutrition, the hs-CRP in the test group was lower than that control group, LYM and PA were higher than those control group [hs-CRP (mg/L): 129.60±75.18 vs. 185.20±63.74, LYM: 1.00±0.84 vs. 0.60±0.41, PA (mg/L): 27.30±3.66 vs. 22.30±2.55, all P < 0.05]. On day 5 of initiated enteral nutrition, the hs-CRP, Neut%, PCT in the test group were lower than those control group, LYM and PA were higher than those control group [hs-CRP (mg/L): 101.70±54.32 vs. 148.40±36.35, Neut%: (85.50±7.66)% vs. (92.90±6.01)%, PCT (μg/L): 0.7 (0.3, 2.7) vs. 3.6 (1.2, 7.5), LYM: 1.00±0.68 vs. 0.50±0.38, PA (mg/L): 27.10±4.57 vs. 20.80 ± 3.51, all P < 0.05]. There were no significantly differences in IL-6 and RBP between the two groups at different time points. ③ The proportion of 50% and 70% of achieved target energy in the test group on day 3, day 5 of initiated enteral nutrition were higher than those of the control group (70.0% vs. 36.4%, 70.0% vs. 36.4%, both P < 0.05). ④ The incidence of reflux/aspiration and VAP in the test group on day 5 of initiated enteral nutrition were significantly lower than those control group (incidence of reflux/aspiration: 5.0% vs. 28.6%, incidence of VAP: 10.0% vs. 36.4%, both P < 0.05). Conclusion:Dynamic monitoring of GRV by bedside ultrasound can accurately improve the proportion of 50% of achieved target energy on day 3 and 75% on day 5 in severe mechanical ventilation patients, improve the patient's inflammation, immune and nutritional status, and can prevent the occurrence of reflux/aspiration and VAP.

As the global population continues to age, the incidence of Alzheimer’s disease (AD), one of the most common neurodegenerative diseases, continues to rise significantly. As the disease progresses, the patient’s daily living abilities gradually decline, potentially leading to a complete loss of self-care abilities. According to estimates by the Alzheimer’s Association and the World Health Organization, AD accounts for 60%-70% of all other dementia cases, affecting over 55 million people worldwide. The case number is estimated to double by 2050. Despite extensive research, the precise etiology and pathogenesis of AD remain elusive. Researchers have a profound understanding of the disease’s pathological hallmarks, which include amyloid plaques and neurofibrillary tangles resulting from the abnormal phosphorylation of Tau protein. However, the exact causes and mechanisms of the disease are still not fully understood, leaving a vital gap in our knowledge and understanding of this debilitating disease. A crucial player that has recently emerged in the field of AD research is the α7 nicotinic acetylcholine receptor (α7nAChR). α7nAChR is composed of five identical α7 subunits that form a homopentamer. This receptor is a significant subtype of acetylcholine receptor in the central nervous system and is widely distributed in various regions of the brain. It is particularly prevalent in the hippocampus and cortical areas, which are regions associated with learning and memory. α7nAChR plays a pivotal role in several neurological processes, including neurotransmitter release, neuronal plasticity, cell signal transduction, and inflammatory response, suggesting its potential involvement in numerous neurodegenerative diseases, including AD. In recent years, the role of α7nAChR in AD has been the focus of extensive research. Emerging evidence suggests that α7nAChR is involved in several critical steps in the disease progression of AD. These include involvement in the metabolism of amyloid β-protein (Aβ), the phosphorylation of Tau protein, neuroinflammatory response, and oxidative stress. Each of these processes contributes to the development and progression of AD, and the involvement of α7nAChR in these processes suggests that it may play a crucial role in the disease’s pathogenesis. The potential significance of α7nAChR in AD is further reinforced by the observation that alterations in its function or expression can have significant effects on cognitive abilities. These findings suggest that α7nAChR could be a promising target for therapeutic intervention in AD. At present, the results of drug clinical studies targeting α7nAChR show that these compounds have improvement and therapeutic effects in AD patients, but they have not reached the degree of being widely used in clinical practice, and their drug development still faces many challenges. Therefore, more research is needed to fully understand its role and to develop effective treatments based on this understanding. This review aims to summarize the current understanding of the association between α7nAChR and AD pathogenesis. We provide an overview of the latest research developments and insights, and highlight potential avenues for future research. As we deepen our understanding of the role of α7nAChR in AD, it is hoped that this will pave the way for the development of novel therapeutic strategies for this devastating disease. By targeting α7nAChR, we may be able to develop more effective treatments for AD, ultimately improving the quality of life for patients and their families.

BACKGROUND:Arthroplasty is the primary treatment for displaced femoral neck fractures in the elderly,and the choice of total hip arthroplasty versus hemiarthroplasty is currently the subject of considerable debate. OBJECTIVE:To compare the mid-and long-term survival status of total hip arthroplasty versus hemiarthroplasty under a direct anterior approach for displaced femoral neck fractures in the elderly based on the propensity score matching method. METHODS:One hundred and forty-seven elderly patients(≥65 years of age)with displaced femoral neck fractures were admitted from January 2016 to January 2021,of whom 88 had total hip arthroplasty(total hip arthroplasty group)and 59 had artificial femoral head replacement(hemiarthroplasty group).For the patients'preoperative comorbidities,the age-corrected Charlson Comorbidity Scale was used to quantify the scores and calculate patient frailty.The propensity score matching method was used to match the two groups 1:1 and to compare the operation time,bleeding,postoperative hospitalization time,hospitalization cost,nutritional index,postoperative complications,and mortality between the two groups after matching.Postoperative survival time was determined by Kaplan-Meier Survival analysis. RESULTS AND CONCLUSION:(1)After propensity score matching,a total of 42 matched pairs were successful in both groups,and the preoperative data of patients in both groups were balanced and comparable after matching(P>0.05).(2)Compared with the hemiarthroplasty group,operation time(79.71 minutes vs.59.07 minutes,P<0.001),bleeding volume(839.64 mL vs.597.83 mL,P=0.001),and hospitalization cost(56 508.15 yuan vs.41 702.85 yuan,P<0.001)were significantly higher in the total hip arthroplasty group.However,the mortality rate was lower in the total hip arthroplasty group than in the hemiarthroplasty group(36%vs.57%,HR=0.44,95%CI:0.23-0.87,P=0.018),and the mean survival time was longer in the total hip arthroplasty group than in the hemiarthroplasty group(59.4 months vs.43.7 months,P=0.024).(3)There were no statistically significant differences in postoperative hospitalization time,preoperative and postoperative nutritional indicators,and overall postoperative complication rate between the two groups(P>0.05).However,in terms of postoperative pain,the incidence of pain was significantly higher in the hemiarthroplasty group than that in the total hip arthroplasty group(24%vs.7%,P=0.035).(4)Overall,total hip arthroplasty has a better prognosis for survival,while hemiarthroplasty is more appropriate for patients with poor physical fitness.At the same time,postoperative pain may largely affect the quality and survival time of patients after hip arthroplasty.

ObjectiveTo investigate the effect of Gegen Qinliantang on glucose and lipid metabolism in the rat model of catch-up growth （CUG） induced by a high-fat diet and the underlying mechanism. MethodA total of 60 SD rats were randomized into a normal control group （n=18） and a modeling group （n=42）. The rat model of CUG was established with a restricted diet followed by a high-fat diet， and the changes of general status and body weight were observed. The levels of fasting blood glucose （FBG）， fasting insulin （FINS）， triglyceride （TG）， and total cholesterol （TC） were measured in 6 rats in each group at the end of the 4^th and 8^th week， respectively. The homeostasis model assessment of insulin resistance index （HOMA-IR） was calculated， and the insulin sensitivity and body composition changes of CUG rats were evaluated. The successfully modeled rats were assigned into 6 groups： normal control， model， high-， medium-， and low-dose Gegen Qinliantang （2.5， 5， 10 g·kg^-1）， and pioglitazone （3.125 mg·kg^-1）. The rats were administrated with corresponding drugs by gavage for 6 weeks， and the normal control group and model group were administrated with the same amount of normal saline. During the experiment period， the changes of body weight were recorded， and the FBG， FINS， HOMA-IR， TG， and TC were determined at the end of the experiment. Hematoxylin-eosin （HE） staining was employed to observe the pathological changes of skeletal muscle in rats. The levels of reactive oxygen species （ROS） and malondialdehyde （MDA） in the skeletal muscle were measured strictly according to the manuals of the reagent kits. Real-time fluorescence quantitative polymerase chain reaction （Real-time PCR） was performed to measure the mRNA levels of silencing information regulator 1 （SIRT1）， peroxisome proliferator-activated receptor-gamma coactivator1α （PGC1α）， and nuclear respiratory factor 1 （Nrf1） in the skeletal muscle. Western blot and immunohistochemistry were employed to assess the expression of SIRT1， PGC1α， and Nrf1 in the skeletal muscle. ResultCompared with the normal control group， the model group presented elevated levels of FBG， FINS， TG， and TC （P<0.05， P<0.01）， increased HOMA-IR （P<0.01）， increased diameter of muscle fibers and adipocytes between muscle cells in the skeletal muscle， rising levels of ROS and MDA in the skeletal muscle （P<0.01）， and down-regulated mRNA and protein levels of SIRT1， PGC1α， and Nrf1 （P<0.05， P<0.01）. Compared with the model group， Gegen Qinliantang （especially the medium and high doses） and pioglitazone decreased the body weight， FINS， HOMA-IR， and TG （P<0.05， P<0.01） and reduced interstitial components such as intermuscular fat in the skeletal muscles and the diameter of muscle fibers. Furthermore， the drugs lowerd the levels of ROS and MDA （P<0.05， P<0.01） and up-regulated the mRNA and protein levels of SIRT1， PGC1α， and Nrf1 （P<0.05， P<0.01） in the skeletal muscle. ConclusionGegen Qinliantang can ameliorate the glucose and lipid metabolism disorders and insulin resistance in CUG rats by regulating the SIRT1/PGC1α/Nrf1 signaling pathway.

Objective To evaluate the bioequivalence of a single oral dose of ritonavir in fasted and fed conditions in healthy Chinese adult subjects with the test and reference formulations.Methods A single-center,open-label,randomized,single-dose,two-periods,two-sequence crossover design was used,and 64 subjects were enrolled in both the fasted and fed groups.The subjects received 100 mg of the test preparation or reference preparation orally per cycle,and the drug concentration of ritonavir in plasma was detected using the high performance liquid chromatography-tandem mass spectrometry(HPLC-MS/MS)method.Pharmacokinetic parameters were estimated by a non-compartment model,and SAS 9.4 software was used for statistical analysis.Results Arithmetic mean values of the main pharmacokinetic parameters of the subject formulation of ritonavir tablets and the reference formulation in the fasting group:Cmax were(791.90±400.20)and(809.60±449.14)ng·mL-1;AUC0_t were(6 072.61±2 631.98)and(6 296.30±3 388.95)ng·h·mL-1;AUC0-∞ were(6 129.59±2 655.57)and(6 347.26±3 434.12)ng·h·mL-1,respectively.Arithmetic mean values of the main pharmacokinetic parameters of the subject formulation of ritonavir tablets and the reference formulation in the fed group:Cmax were(512.37±233.60)and(521.74±223.87)ng·mL-1;AUC0_t were(4 203.43±2 221.33)and(4 200.13±1 993.50)ng·h·mL-1;AUC0_∞ were(4 259.21±2 266.88)and(4 259.63±2 044.12)ng·h·mL-1.The 90％confidence intervals for the geometric mean ratios of Cmax,AUC0_t and AUC0_∞ of the prototype drug ritonavir in plasma after oral administration of 100 mg of the test and reference formulations of ritonavir tablets under fasting and fed conditions fell within the 80.00％to 125.00％equivalence interval.Conclusion The test and reference formulations of ritonavir tablets were bioequivalent under fasting and postprandial conditions.

Objective This study investigated the impact of occupational mercury(Hg)exposure on human gene transcription and expression,and its potential biological mechanisms. Methods Differentially expressed genes related to Hg exposure were identified and validated using gene expression microarray analysis and extended validation.Hg-exposed cell models and PTEN low-expression models were established in vitro using 293T cells.PTEN gene expression was assessed using qRT-PCR,and Western blotting was used to measure PTEN,AKT,and PI3K protein levels.IL-6 expression was determined by ELISA. Results Combined findings from gene expression microarray analysis,bioinformatics,and population expansion validation indicated significant downregulation of the PTEN gene in the high-concentration Hg exposure group.In the Hg-exposed cell model(25 and 10 μmol/L),a significant decrease in PTEN expression was observed,accompanied by a significant increase in PI3K,AKT,and IL-6 expression.Similarly,a low-expression cell model demonstrated that PTEN gene knockdown led to a significant decrease in PTEN protein expression and a substantial increase in PI3K,AKT,and IL-6 levels. Conclusion This is the first study to report that Hg exposure downregulates the PTEN gene,activates the PI3K/AKT regulatory pathway,and increases the expression of inflammatory factors,ultimately resulting in kidney inflammation.

Objective To investigate the role of magnesium ion(Mg2+)in cisplatin-induced acute kidney injury(Cis-AKI)in kidney organoids and HK-2 cells,as well as the potential mechanism.Methods Initially,we utilized human-derived induced pluripotent stem cells(iPSCs)to construct kidney organoids,and then built a Cis-AKI model based on kidney organoids.HE staining was used to observe the structure of kidney organoids,and immunofluorescence staining was used to observe the localization of markers and the expression of cleaved caspase-3.qRT-PCR was conducted to detect mRNA levels of tubular and glomerular markers,as well as inflammatory factors.Subsequently,the kidney organoids were randomly divided into control group,cisplatin group(Cis group),and Mg2+pretreatment group(Cis+Mg2+group).CCK-8 and ATP content assays were employed to evaluate the cell viability of renal tubular epithelial cells.TUNEL staining was performed to detect the apoptosis of renal tubular epithelial cells.Western blot was utilized to detect the expression of apoptosis-associated proteins(Bcl-2,Bax,cleaved caspase-3)and organic cation transporter 2(OCT2).Immunofluorescence was used to detect the localization and expression of OCT2.Results On the 10th day,the tubular structure in kidney organoids was visible,with abundant expression of renal markers.Treatment with 10 μmol/L cisplatin resulted in structural damage to kidney organoids,significantly increased expression of cleaved caspase-3 and mRNA levels of inflammatory factors,and significantly decreased ATP content.Compared with the Cis group,the Cis+Mg2+group showed increased ATP content in kidney organoids,reduced number of TUNEL-positive cells,significantly decreased expression of apoptosis-associated proteins,and significantly decreased expression of OCT2.However,there was no significant improvement in HK-2 cell viability,the number of TUNEL-positive cells,or apoptosis-associated proteins in the Cis+Mg2+group,and HK-2 cells did not express OCT2.Conclusion Kidney organoid is an ideal in vitro model to study the pathogenesis and treatment of Cis-AKI.Mg2+pretreatment can significantly reduce the damage of kidney organoids induced by cisplatin,and the mechanism may be related to the downregulation of OCT2.

Objective To construct and identify an organoid model of human placental site trophoblastic tumor(PSTT).Methods The tumor cells were obtained by digesting and separating the PSTT tissues and then embedded in Matrigel.The organoids were cultured in the specific organoid medium.The histological morphology of the organoid model was observed by HE staining and the expression levels of the PSTT specific markers[human placental prolactin(HPL),human leukocyte antigen-G(HLA-G)and placental alkaline phosphatase(PLAP)]were detected by immunohistochemistry and immunofluorescence,so as to evaluate the consistency between the organoid model and the PSTT tissue.Meanwhile,the morphology and forming efficiency of the constructed model were observed under a microscope after primary culture,passage generation and cryopreservation to evaluate its potential application as an organoid model in basic and clinical translational research of PSTT.Results The constructed organoid model could proliferate stably,growing from small microspheres into compact solid spheres or spheres with follicle-like structures,and could passage after fully grown in 7-10 days.The cell state remained stable after passage,frozen storage and recovery.HE staining showed that the morphology of the cells in the organoids was similar to that of the primary PSTT tumor cells,and immunofluorescence staining showed that the organoids highly expressed HLA-G and lowly expressed β-HCG,indicating that the constructed organoid model mainly contained intermediate trophoblast.Conclusion The adult-derived PSTT organoid(ADPO)models were successfully established.

This paper aims to discuss the ideas and experience about the radiology residency training system of Canada with a presentation of its base accreditation standards for five aspects, competency goals for seven roles, four stages of training arrangement, and two types of final assessment questions. Although the Canada's radiology residency program differs from China's standardized resident and specialist training programs for radiology, there are still several points that are worth referencing, including emphasizing the training priority of competency goals, providing a specific basis for the stratification of training, offering clear guidance for the implementation of training content, and improving assessment methods to focus on competency goals. These points are of great value for improving the standardized radiology resident and specialist training programs in China, so as to provide a reference for the training of excellent radiologists in China.