Objective To establish a highly sensitive,stable,and universally applicable ultra-high-performance liquid mass spectrometry tandem method(UPLC-MS/MS)for simultaneous determination of nirmatrelvir and ritonavir blood concentrations in human plasma.Methods The separation was performed on an ACQUITY UPLC BEH C18 column(2.1 mm× 50 mm,1.7 μm)with gradient elution,and the mobile phase consisted of 0.1％formic acid-water and 100％acetonitrile at the flow rate of 0.3 mL·min-1.The column temperature was 45℃,and the injection volume was 2 μL.Electrospray ionization as ion source(ESI+)was used as the ion source and multiple reactions monitoring mode(nirmatrelvir m/z 500.20→319.10,nirmatrelvir-D9 m/z 508.59→328.10,ritonavir m/z 721.30→426.10,13C,2H3-ritonavir m/z 725.30→426.10)was adopted.Thirty patients with coronavirus disease 2019(COVID-19)treated with nirmatrelvir and ritonavir at the People's Hospital of Changxing County in Jan.2023 were selected to measure their steady-state trough concentrations of nirmatrelvir and ritonavir after 3 days of treatment.Results The linear range of nirmatrelvir was 0.100-10.0 μg·mL-1(R2=0.997 2),and the linear range of nirmatrelvir was 0.050-5.00 μg·mL-1(R2=0.995 2).The recovery rates of nirmatrelvir and lopinavir were both＞90％and the intra-batch and inter-batch precision relative standard deviations(RSDs)were both＜10％.Additionally,the recovery ranges for nirmatrelvir and lopinavir were 91.5％-97.0％,and the matrix effects ranged from 92.4％to 97.7％.The results of clinical samples showed that the plasma concentrations of nirmatrelvir and ritonavir in patients with COVID-19 varied greatly among individuals.Conclusion The method for simultaneous determination of nirmatrelvir and ritonavir concentrations in human plasma established in this study is convenient,highly specific,highly accurate,with high precision,which is suitable for monitoring the concentrations of nirmatrelvir and ritonavir in patients.

Objective: To investigate the experience of child sexual abuse (CSA) and depressive symptoms among young men who sex with men (YMSM) in Guangzhou, and then to explore the impact of CSA on depressive symptoms. Methods: A convenient sampling method was used to recruit MSM. YMSM who aged 18-24 and have lived in Guangzhou for more than 3 months were included in this study. Data on demographic characteristics, homosexual partners seeking behaviors, sexual orientation, CSA experience and depression were collected through an electronic questionnaire. χ 2 tests were used to compare the proportion of CSA and depressive symptoms among YMSM with different characteristics. Logistic regressions were preformed to assess the impact of CSA on depression. Results: The proportion of CSA experience and depressive symptoms among participants were 31.51% (115/365) and 47.95% (175/365), respectively. Participants with junior high school education or lower and who sought homosexual partners offline reported(75.00%,62.22%) a higher proportion of depressive symptoms( χ 2=7.97，4.19， P <0.05). After adjusting for factors e.g. ethnicity, residence, resident duration in Guangzhou, studentship, education, monthly income, sexual orientation and homosexual partners seeking behaviors, the multivariable Logistic regression model showed that YMSM with CSA experience (a OR=1.81, 95%CI =1.12-2.93) were more likely to have depressive symptoms than those without CSA experience. Conclusion The prevalence of CSA experience and depressive symptom is relatively high among YMSM in Guangzhou, and CSA experience is associated with higher risk of depressive symptoms. More attention should be paid to strengthen the psychological intervention for YMSM, especially for those who experienced CSA, so as to reduce the risk of depression and improve mental health among YMSM.

Objective: To examine the prevalence and associated factors of seeking casual male sexual partners among men who have sex with men (MSM) students in Guangzhou, and to provide a reference for health education and intervention. Methods: A cross-sectional study was conducted to recruit 189 MSM students aged 18 and 28 via voluntary counseling and testing (VCT) clinics, Lingnan partners and Zhitong charity from May 2017 to April 2018. An anonymous electronic questionnaire was administrated to collect information on sociodemographic and sexual behavior characteristics. Chi-square test and non-conditional Logistic regression analysis were performed to explore the associated factors of casual homosexual behavior among MSM students. Results: In the past 6 months, 63.49% (120/189) of them reported casual male partners, and the rate of consistent condom use was 61.67%(74/120). Multivariate Logistic regression analysis showed that participants who had multiple sex partners in the past 6 months were more likely to seek male casual partners(aOR=9.13, 95%CI=4.27-19.53). Individuals who used recreational drugs before sex were at a higher risk of having casual sex behaviors(aOR=3.06, 95%CI=1.08-8.62). MSM students who had steady homosexual partners had a lower risk to seek casual sex(aOR=0.43, 95%CI=0.19-0.98). Conclusion The proportion of seeking casual male sexual partners among MSM students in Guangzhou was relatively high. The publicity and education should be strengthened among those who had multiple sex partners, with no steady homosexual partners and used recreational drugs before sex, to reduce the casual sex behaviors.

Objective: To retrospectively analyze the laboratory findings and ultrasonographic features in acute phase of children suffering from Kawasaki disease (KD) with stable hemodynamics and Kawasaki disease shock syndrome (KDSS), so as to provide the evidence for early diagnosis, timely treatment and improvement of prognosis of KDSS. Methods: Four hundred and eighteen patients with KD diagnosed at Shenzhen Children′s Hospital from November 2016 to May 2018 were selected, including 23 KDSS patients(KDSS group) and 395 cases with stable hemodynamic(KD without shock group). The clinical characteristics, laboratory index and ultrasonic examination data of the 2 groups were collected and compared for statistical conclusion. Results: (1)The level of C-reaction protein(CRP)[166.20 mg/L (74.40 mg/L)], γ-glutamyl transpeptidase(γ-GT)[88.00 IU/L (126.00 IU/L)], creatine kinase isoenzyme(CKI)[1.78 μg/L (5.17 μg/L)], troponin(TP)[0.01 μg/L (0.39 μg/L)] in the KDSS group in acute phase were all higher than those in the KD without shock group[70.50 mg/L (54.30 mg/L), 40.00 IU/L (89.00 IU/L), 1.20 μg/L (0.85 μg/L), 0.01 μg/L (0.01 μg/L)], hemoglobin(Hb)[90.00 g/L (15.00 g/L)], ablumin [24.20 g/L (4.30 g/L)], serum sodium[130.90 mmol/L (5.60 mmol/L)] levels in the KDSS group were lower than those in the KD without shock group[107.00 g/L (14.00 g/L), 33.40 g/L (4.08 g/L), 136.10 mmol/L (3.25 mmol/L)], and the differences were statistically significant (all P<0.05). (2)The incidence rates of impaired left ventricular ejection fraction(LVEF)[<55%: 3 cases (13.03%) vs.8 cases (2.00%)], coronary artery abnormalities[left anterior descending branch(LAD) Z-score>2.5: 6 cases (26.09%) vs.35 cases (8.86%)]and valvular regurgitation[tricuspid regurgitation(TR)≥moderate: 3 cases (13.03%) vs.5 cases (1.26%)]in the KDSS group were higher than those in the KD without shock group, and the differences were statistically significant (all P<0.05). (3)Among acute phase in KDSS group, 9 cases (39.13%) had liver enlargement, 9 cases (39.13%) had peritoneal effusion, 3 cases (13.04%) had diffuse renal lesions, 3 cases (13.04%) had joint effusion (2 cases of knee joint effusion, 1 case of hip joint effusion), and 2 cases (8.70%) had enteritis.In the KD without shock group, only 3 cases (0.76%) had hepatomegaly and 2 cases (0.51%) had a small amount of knee effusion. Conclusions Laboratory findings of KDSS group showed higher level of CRP, CKI, TP as well as γ-GT than those in KD without shock group, who are more prone to suffer from hypohemoglobin, hyponatremia and hypoalbuminemia.Ultrasound examination showed that KDSS children were more prone to have heart or multiple-organ damage.Clinicians should raise their awareness to provide comprehensive assessment as well as timely and effective treatment.

Objective To investigate the effects of Dingkoulizhong decoction on cellular immune factors and adverse reactions in patients with advanced gastric cancer treated with chemotherapy.Methods One hundred and thirty-eight patients with advanced gastric cancer were enrolled in our hospital from October 2014to December 2016,and were randomly divided into control group (n =69) and observation group (n =69) by using the random number table.The patients of the control group were treated with FOLFOX4 chemotherapy (oxaliplatin + calcium folinate + fluorouracil),while the patients of the observation group were given by the treatment of Dingkoulizhong decoction on the basis of the control group.The peripheral blood samples of the patients were collected before and after the treatment.The levels of cellular immune factors CD3 +,CD4 +,CD8 + and CD4 +/CD8 + were detected,and the clinical efficacy and adverse reactions of the patients of the two groups were observed.Results After the treatment,the number of complete remission (CR),partial remission (PR),stable disease (SD) and progressive disease (PD) in the observation group were 16,25,16 and 12 cases respectively,while the control group were 9,20,19 and 21 cases respectively,and there was a statistically significant difference in the distribution of clinical efficacy between the two groups (Z =4.381,P =0.036).Compared with the control group,the clinical benefit rate (CBR) of the observation group was significantly improved (59.42％ vs.42.03％),with a statistically significant difference (x2 =4.175,P =0.041).The cellular immune factors CD3 + [(52.67 ±6.21)％ vs.(53.45 ±6.54)％],CD4 + [(23.56 ±3.85)％ vs.(24.09±2.91)％],CD8 +[(28.16±3.49)％ vs.(27.87±3.26)％] and CD4 +/CD8+(1.13 ± 0.27 vs.1.19 ±± 0.31) of the patients of the observation group showed no statistically significant difference (t=0.718,P=0.474;t=0.912,P=0.363;t=0.504,P=0.615;t=1.212,P=0.227) beforeand after the treatment,but the cellular immune factor CD3 + [(50.36 ± 3.74)％ vs.(53.13 ± 6.12)％],CD4 +[(21.26±2.37)％ vs.(23.44 ±3.96)％] andCD4+/CD8*(0.96±0.26vs.1.15±0.25) of the patients of the control group after the treatment were significantly lower than those before the treatment,and CD8 +[(31.64 ± 4.05) ％ vs.(27.98 ± 3.52) ％] after the treatment was significantly higher than that before the treatment,all with statistically significant differences (t =3.208,P ＜ 0.001;t =3.924,P ＜ 0.001;t =4.289P ＜ 0.001,t =5.666,P ＜ 0.001).Compared with the control group,the level of CD3 + [(53.45 ± 6.54) ％ vs.(50.36±±3.74)％],CD4+[(24.09±±2.91)％ vs.(21.26±2.37)％] andCD4+/CD8+(1.19±0.31vs.0.96 ± 0.26) of the patients of the observation group after the treatment were significantly improved,and CD8 +[(27.87 ± 3.26) ％ vs.(31.64 ± 4.05) ％] was significantly decreased,all with statistically significant differences (t=3.407,P=0.001;t =6.264,P＜0.001;t =4.722,P＜0.001;t =6.023,P＜0.001).Compared with the control group,the total adverse reaction rate of the observation group was significantly decreased (36.23％ vs.55.07％),with a statistically significant difference (x2 =4.936,P =0.026).Conclusion Dingkoulizhong decoction can significantly improve the clinical efficacy in patients with advanced gastric cancer treated with chemotherapy,alleviate the immune function damage caused by chemotherapy,and it can reduce the occurrence of adverse reactions.

Objective To investigate the effect of endoplasmic reticulum stress on sensitivity of glioma cell line U87 to temozolomide (TMZ) and underlying mechanism.Methods (1) Glioma U87 cells were routinely cultured for 24 h in vitro;different concentrations of TMZ (0,12.5,25,50,100 μmol/L) were added to intervene the cell proliferation of U87 cells for 24 h;MTT method was used to detect the cellular proliferation inhibition rate,and half maximal inhibitory concentration (IC50) of TMZ was calculated;tunicamycin (TM) treatment (0,2,4,8 μmol/L) was given to the cells for 6 h,and then,50 μmol/L TMZ was given for 24 h,and cellular proliferation inhibition rate of U87 was detect by MTT method.(2) U87 cells were randomly divided into control group,TM group,TMZ group and TM+TMZ group;pretreatment of TM for 6 h was given to cells from TM group and TM+TMZ group;and 50 μmol/L TMZ was given to cells from TMZ group and TM+TMZ group;same amount of medium was given to cells from control group;24 h after treatment,the apoptotic rate was examined by flow cytometry;Westem blotting was used to detect the protein expressions of caspase-3,B-cell lymphoma 2 associated X protein (Bax),O-6-methlguanine-DNA methyltransferase (MGMT),glucose-regulated protein 78 (GRP78),and inositol-requiring enzyme 1 (IRE-l).Results (1) MTT showed that IC50 of TMZ was 50 μmol/L.As compared with that of 0 μmol/L TM+50 μmol/L TMZ group or 2 μmol/L TM+50 μmol/L TMZ group,the cellular proliferation inhibition rate of 4 μmol/L TM+50 μmol/L TMZ group and 8 μmol/L TM+50 μmol/L TMZ group was significantly decreased (P＜0.05).(2) As compared with TMZ group,TM+TMZ group had significantly decreased apoptotic rate (46.98％±4.79％ vs.35.74％ ±4.09％),significantly decreased caspase-3 and Bax protein expressions,and significantly increased MGMT,GRP78 and IRE-1 protein expressions (P＜0.05).Conclusion Endoplasmic reticulum stress can increase the resistance gene MGMT expression,decrease the chemotherapy sensitivity to TMZ,and induce chemoresistance ofglioma cell line U87.

Objective To investigate the effects of mannan-binding lectin ( MBL) on the differen-tiation of Th17 cells (T helper cell 17, Th17). Methods CD4+T cells were separated in vitro from fresh human cord blood by MACS ( magnetic-activated cell sorting ) separator. Anti-CD3 monoclonal antibody ( McAb) and anti-CD28 McAb were used to stimulate CD4+T cells with IL-6 and TGF-β1 as inducers. Then, these cells were treated with ( MBL group) or without ( control group) different concentrations of MBL. Percentages of Th17 cells in different groups were detected by fluorescence-activated cell sorting( FACS) after 72 hours of culturing. Quantitative real-time PCR ( Q-PCR) was used to analyze the expres-sion of RORγt ( retinoid-related orphan receptor-γ-t) at mRNA level in both control and MBL groups. En-zyme-linked immunosorbent assay (ELISA) was performed to detect the levels of IL-17A in supernatants of cell culture from different groups. FACS was used to detect the percentages of Th17 cells in MBL-/-and wild type ( WT) mice. Results MBL could significantly reduce the percentage of Th17 cells after 72 hours of culturing as compared with the control group. Moreover, MBL could significantly down-regulate the expres-sion of RORγt at mRNA level and decrease the expression of IL-17A. Results of animal experiments showed that the percentages of CD4+RORγt+Th17 cells in MBL-/- mice were significantly higher than those in WT mice. Conclusion MBL can inhibit the differentiation of CD4+T cells to Th17 cells, which is induced by IL-6 and TGF-β1.

Objective To evaluate the miRNA change between hypothermia circulatory arrest at different temperature and its impact on intestinal protection.Methods Sixteen piglets were randomly(n =4) divided into four groups:deep hypothermia circulatory arrest (DHCA,18℃) group,moderate hypothermia circulatory arrest(MHCA,24℃) group,cardiopulmonary bypass(CPB) group and sham operation(SO) group.They were subjected to 80 min hypothermia circulatory arrest,305 min CPB or thoracotomy,respectively.Pick-and-mix custom miRNA real-time PCR panels were utilized to detect intestinal samples.miRNA expression between DHCA and MHCA were compared directly(DHCA vs.MHCA) and indirectly(DHCA/SO vs.MHCA/SO,DHCA/CPB vs.MHCA/CPB).Results Exposure to DHCA caused less intestinal miRNA dysregulation than MHCA.Besides,seven miRNAs(miR-122,miR-145-5p,miR-421-5p,miR-99a,miR-365-5p,miR-31 and miR-192)were differentially expressed between the two hypothermia circulatory arrest groups.Conclusion Better intestinal miRNA protection was provided by DHCA than MHCA.Intestinal miRNA were differentially expressed between hypothermia circulatory arrest at different temperature.

Objective: To discuss the impact of updated definition and classification system of pancreatic fistula published in 2016 on the postoperative classification of pancreatic fistula. Methods: Retrospective analysis was made on patients who underwent pancreatic surgery at ward 1 in Department of General Surgery, Peking Union Medical College Hospital from January 2015 to December 2016.A total of 408 patients were included in this retrospective study, male/female was 184/224, aged from 9 to 81 years with mean age of 51.6 years.One hundred and fifty-two cases were performed pancreaticoduodenectomy, 125 cases for distal pancreatectomy, 43 cases for spleen preservation distal pancreatectomy, 61 cases for partital pancreatectomy or enucleation, 8 cases for middle pancreatectomy, 6 cases for pancreaticojejunostomy and 13 cases for other procedures.Clinical data including postoperative drainage fluid volume, amylase concentration, duration of hospitalization and drainage were obtained, revaluated and re-analyzed, classified grounded on 2005 edition and 2016 edition, respectively.t-test was adopted for data analysis. Results: According to the previous standards, the incident rate of pancreatic fistula was 57.4%, and the incident rate of B-level plus C-level pancreatic fistula was 35.8%, which decreased to 13.7% based on 2016 edition.Nine patients who received percutaneous puncture or endoscopic drainage was regraded from C-level to B-level. The average duration of postoperative hospitalization of patients without pancreatic fistula was (12.5±6.0)days, demonstrating no significant difference compared to (14.1±7.7)days, duration of postoperative hospitalization of A-level(under 2005 edition of criteria) pancreatic fistula group(t=1.66, P=0.09) and (12.4±6.1)days, duration of postoperative hospitalization of biochemical leakage group(t=0.14, P=0.89). Nevertheless, there was statistical significant difference between the average postoperative duration of hospitalization(30.7±16.9) days of B-level(under 2016 criteria) pancreatic fistula patients and pancreatic fistula-free patients as well as the biochemical leakage group patients (t=7.10, 7.13; both P<0.01). Conclusions Based on the new diagnostic criteria, the incidence of postoperative pancreatic fistula decreased dramatically.New classification system downgraded part of cases graded C-level pancreatic fistula to B-level and some B-level to biochemical fistula.The new diagnostic classification and criteria facilitated clinical practice, accomplished better conformity to clinical reality and potentially enacted clinical outcome.

OBJECTIVE:To provide reference for improving the national essential medicine system and satisfy the needs of ra-tional use from the public METHODS:The current situation and existing problems in the national essential system were described by literature research and comparative analysis,and recommendations were presented. RESULTS:The implementation of essential medicine system has certain effects in China,but there still remains some problems,involving too much variety of essential medi-cines,high price and others,and limitation of the use of medicine and distribution in primary medical institutions. CONCLU-SIONS:Government should further simplify the essential medicine lists,reduce prices,strengthen policy support for primary medi-cal institutions,deepen the national essential medicine system and protect the public's rational drug use.