Clinical remission and transmural healing of ustekinumab in patients with Crohn's disease / 北京大学学报(医学版)

Objective:To treat the Crohn's disease(CD)patients with ustekinumab(UST),to eva-luate their clinical and endoscopic remission,and to evaluate their transmural response(TR)and trans-mural healing(TH)condition using intestinal ultrasonography(IUS).Methods:Retrospective analysis was made on patients diagnosed with CD in Peking University People's Hospital from January 2020 to Au-gust 2022,who were treated with UST for remission induction and maintenance therapy.All the patients were evaluated on both week 8 and week 16/20 after treatment,including clinical,biochemical indica-tors,colonoscopy and IUS examination.Results:A total of 13 patients were enrolled in this study,inclu-ding 11 males and 2 females.The minimum age was 23 years,the maximum age was 73 years and the mean age was 36.92 years.All the patients were in the active stage of disease before treatment,and the average Best Crohn's disease activity index(Best CDAI)score was 270.12±105.55.In week 8,the Best CDAI score of the patients decreased from 270.12±105.55 to 133.16±48.66(t=4.977,P＜0.001).Eight patients achieved clinical remission while 5 patients remained in the active stage.Nine patients underwent colonoscopy evaluation.The average simple endoscopic score for Crohn's disease(SES-CD)score decreased from 10.71±7.14 before treatment to 6.00±7.81(t=2.483,P=0.048)in week 16/20.Four patients achieved endoscopic remission while 5 patients did not.In week 8,5 pa-tients achieved TR,2 patients achieved TH,the other 6 patients did not get TR or TH.In week 16/20,6 patients achieved TR,3 patients achieved TH while the other 4 patients did not get TR or TH.There was no significant statistical difference in the TR effect of UST between small intestine and colon lesions(Fisher test,P＞0.999).The rate of UST transmural response in the patients who had had previous bio-logical agent therapy was lower than those with no previous biological agent therapy,but there was no sig-nificant statistical difference(Fisher test,P=0.491).Conclusion:After treatment of UST,the clinical and endoscopic conditions of the CD patients had been improved,and some patients could achieve clini-cal remission and endoscopic remission.UST had good TR and TH effects on CD.TR might appear in week 8,and the TR effect increased in week 16/20.There was no significant statistical difference in the TR effect between small intestine and colon lesions.TR effect of UST was better in the patients who had no previous biological agent therapy than those who had had other biological agents,but the result had no significant statistical difference.

Scutellarin inhibitting BV-2 microglia-mediated neuroinflammation via the cyclic GMP-AMP synthase-stimulator of interferon gene pathway / 解剖学报

Objective To explore the effect of scutellarin on lipopolysaccharide(LPS)induced neuroinflammation in BV-2 microglia cells.Methods BV-2 microglia were cultured and randomly divided into 6 groups:control group(Ctrl),cyclic GMP-AMP synthetase(cGAS)inhibitor RU320521 group(RU.521 group),LPS group,LPS+RU.521 group,LPS+scutellarin pretreatment group(LPS+S)and LPS+S+RU.521 group.The expressions of cGAS,stimulator of interferon gene(STING),nuclear factor kappa B(NF-κB),phosphorylated NF-κB(p-NF-κB),neuroinflammatory factors PYD domains-containing protein 3(NLRP3)and tumor necrosis factor α(TNF-α)in BV-2 microglia were detected by Western blotting and immunofluorescent double staining(n= 3).Results Western blotting and immunofluorescent double staining showed that compared with the control group,the expression of cGAS,STING,p-NF-κB,NLRP3 and TNF-α in BV-2 microglia increased significantly after LPS induction(P<0.05),while the expression of cGAS,STING,p-NF-κB,NLRP3 and TNF-α in LPS+S group were significantly lower than those in LPS group(P<0.05).Treatment with cGAS pathway inhibitor RU.521 showed similar effects as the pre-treatment group with scutellarin.In addition,the change of NF-κB in each group was not statistically significant(P>0.05).Conclusion Scutellarin inhibits the neuroinflammation mediated by BV-2 microglia cells,which may be related to cGAS-STING signaling pathway.

Simultaneous content determination of seventeen constituents in Yangxue Ruanjian Capsules by UPLC-MS/MS / 中成药

AIM To establish a UPLC-MS/MS method for the simultaneous content determination of liquiritin apioside,alibiflorin,swertiamarin,methyl gallate,benzoylpaeoniflorin,sweroside,6′-O-β-D-glucosylgentiopicroside,isoliquiritigenin,loganic acid,liquiritigenin,gallic acid,paeoniflorin,oxypaeoniflorin,gentiopicroside,glycyrrhizic acid,isoliquiritoside and liquiritin in Yangxue Ruanjian Capsules.METHODS The analysis was performed on a 40℃thermostatic Waters BEH C18column(2.1 mm×100 mm,1.7 μm),with the mobile phase comprising of 2 mmol/L ammonium acetate(containing 0.1%formic acid)-acetonitrile flowing at 0.3 mL/min in a gradient elution manner,and electron spray ionization source was adopted in negative ion scanning with multiple reaction monitoring mode.RESULTS Seventeen constituents showed good linear relationships within their own ranges(r>0.999 6),whose average recoveries were 91.33%-104.03%with the RSDs of 1.58%-3.50%.CONCLUSION This rapid,accurate and stable method can be used for the quality control of Yangxue Ruanjian Capsules.

Research progress on pathogenicity and related virulence factors of Klebsiella oxytoca / 中华检验医学杂志

Klebsiella oxytoca is an important opportunistic pathogen which cause community or hospital-acquired infections in adults and children. The disease it most causes is antibiotic-associated hemorrhagic colitis (AAHC). It can also cause diseases such as urinary tract infections, pneumonia and bloodstream infections. The cytotoxins including Tilivalline and Tilimycin are important virulence factors for Klebsiella oxytoca, mainly causing AAHC. This article reviewed the progress of research on the prevalence, pathogenicity and mechanisms of K.oxytoca, hoping to improve the understanding of K.oxytoca and provide guidance on disease prevention and treatment.

Effect of Ganmai Dazao Decoction on ethology of rats with PTSD and its mechanism / 中国中药杂志

This study aimed to explore the effect of Ganmai Dazao Decoction on the ethology of rats with posttraumatic stress disorder(PTSD) and study the related mechanism through the changes in magnetic resonance imaging and protein expression. Sixty rats were randomly divided into 6 groups, namely the normal group, the model group, the low(1 g·kg~(-1)), medium(2 g·kg~(-1)), and high-dose Ganmai Dazao Decoction groups(4 g·kg~(-1)), and the positive control group(intragastric administration with 10.8 mg·kg~(-1) of fluoxetine), with 10 rats in each group. Two weeks after inducing PTSD by single-prolonged stress(SPS) in rats, the positive control group was given fluoxetine hydrochloride capsule by gavage, the low, medium, and high-dose groups were given Ganmai Dazao Decoction by gavage, and both the normal group and the model group were given the same volume of normal saline by gavage, each for 7 days. The open field experiment, elevated cross elevated maze, forced swimming experiment, and new object recognition test were carried out for the behavioral test. Three rats in each group were selected to detect the expression of neuropeptide receptor Y1(NPY1R) protein in the hippocampus by Western blot. Then, the other three rats in each group were selected to use the 9.4T magnetic resonance imaging experiment to observe the overall structural changes in the brain region and the anisotropy fraction of the hippocampus. The results of the open field experiment showed that the total distance and central distance of rats in the model group were significantly lower than those in the normal group, and the total distance and central distance of rats in the middle and high-dose Ganmai Dazao Decoction groups were higher than those in the model group. The results of the elevated cross maze test showed that medium and high-dose Ganmai Dazao Decoction remarkably increased the number of open arm entries and the residence time of open arm of rats with PTSD. The results of the forced swimming experiment showed that the immobility time in the water of the model group rats was significantly higher than that of the normal group, and Ganmai Dazao Decoction hugely reduced the immobility time in the water of rats with PTSD. The results of the new object recognition test showed that Ganmai Dazao Decoction significantly increased the exploration time of new objects and familiar objects in rats with PTSD. The results of Western blot showed that Ganmai Dazao Decoction significantly reduced the expression of NYP1R protein in the hippocampus of rats with PTSD. The 9.4T magnetic resonance examination found that there was no significant difference in the structural image among the groups. In the functional image, the fractional anisotropy(FA value) of the hippocampus in the model group was significantly lower than that in the normal group. The FA value of the hippocampus in the middle and high-dose Ganmai Dazao Decoction groups was higher than that in the model group. Ganmai Dazao Decoction reduces the injury of hippocampal neurons by inhibiting the expression of NYP1R in the hippocampus of rats with PTSD, thereby improving the nerve function injury of rats with PTSD and playing a neuroprotective role.

miR-125b-5p inhibits proliferation and migration of osteosarcoma cells by negatively regulating RAB3D expression / 南方医科大学学报

OBJECTIVE@#To investigate the inhibitory effect of miR-125b-5p on proliferation and migration of osteosarcoma and the role of RAB3D in mediating this effect.@*METHODS@#The expression level of miR-125b-5p was detected by qRT-PCR in a normal bone cell line (hFOB1.19) and in two osteosarcoma OS cell lines (MG63 and HOS). A miR-125b-5p mimic or inhibitor was transfected in the osteosarcoma cell lines via liposome and the changes in cell proliferation and migration were detected with EDU and Transwell experiments. Bioinformatic analysis was conducted for predicting the target gene of miR-125b-5p, and the expression level of RAB3D in hFOB1.19, MG63, and HOS cells was detected by Western blotting. In the two osteosarcoma cell lines transfected with miR-125b-5p mimic or inhibitor, the expression levels of RAB3D mRNA and protein in osteosarcoma cells were examined with qRT-PCR and Western blotting. The effects of RAB3D overexpression, RAB3D knockdown, or overexpression of both miR-125b-5p and RAB3D on the proliferation and migration of cells were assessed using EDU and Transwell experiments.@*RESULTS@#The two osteosarcoma cell lines had significantly lower expression levels of miR-125b-5p (P < 0.05). Bioinformatic analysis predicted that RAB3D was a possible target gene regulated by miR-125b-5p. In osteosarcoma cells, overexpression of miR-125b-5p significantly lowered the expression of RAB3D protein (P < 0.05); inhibiting miR-125b-5p expression significantly decreased RAB3D expression only at the protein level (P < 0.05) without obviously affecting its mRNA level. Modulation of miR-125b-5p and RAB3D levels produced opposite effects on proliferation and migration of osteosarcoma cells, and in cells with overexpression of both miR-125b-5p and RAB3D, the effect of RAB3D on cell proliferation and migration was blocked by miR-125b-5p overexpression (P < 0.05).@*CONCLUSION@#Overexpression of miR-125b-5p inhibits the proliferation and migration of osteosarcoma cells by regulating the expression of RAB3D at the post-transcriptional level.

Prenatal diagnosis of pyruvate dehydrogenase E1-α deficiency: a case report / 中华围产医学杂志

This article reported a case of pyruvate dehydrogenase E1-α deficiency suggested by abnormal brain development during prenatal ultrasound imaging. Prenatal ultrasound revealed a mild enlargement of bilateral cerebral ventricles and the possibility of intracranial hemorrhage in the fetus at 25 +1 weeks of gestation. MRI showed the fetus with absent corpus callosum, enlarged bilateral cerebral ventricles and paraventricular cysts. After genetic counseling and careful consideration, the couple opted for pregnancy termination. To clarify the cause of the disease, whole-exome sequencing was performed on the fetal skin to detect possible variants, and which revealed a frameshift mutation c.924_930dup(p.R311Gfs*5) in exon 10 of the PDHA1 gene. Sanger sequencing confirmed the mutation was a de novo pathogenic variant, indicating that the fetus was affected by pyruvate dehydrogenase E1-α deficiency.

Diagnostic efficacy of prostate cancer using targeted biopsy with 6-core systematic biopsy for patients with PI-RADS 5 / 北京大学学报(医学版)

OBJECTIVE@#To investigate the diagnostic efficacy of targeted biopsy (TBx), systematic biopsy (SBx), TBx+6-core SBx in prostate cancer (PCa) / clinically significant prostate cancer (cs-PCa) for patients with prostate imaging reporting and data system (PI-RADS) score of 5, and thereby to explore an optimal sampling scheme.@*METHODS@#The data of 585 patients who underwent multiparametric magnetic resonance imaging (mpMRI) with at least one lesion of PI-RADS score 5 at Peking University First Hospital from January 2019 to June 2022 were retrospectively analyzed. All patients underwent mpMRI / transrectal ultrasound (TRUS) cognitive guided biopsy (TBx+SBx). With the pathological results of combined biopsy as the gold standard, we compared the diagnostic efficacy of TBx only, SBx only, and TBx+6-core SBx for PCa/csPCa. The patients were grouped according to mpMRI T-stage (cT2, cT3, cT4) and the detection rates of different biopsy schemes for PCa/csPCa were compared using Cochran's Q and McNemar tests.@*RESULTS@#Among 585 patients with a PI-RADS score of 5, 560 (95.7%) were positive and 25(4.3%) were negative via TBx+SBx. After stratified according to mpMRI T-stage, 233 patients (39.8%) were found in cT2 stage, 214 patients (36.6%) in cT3 stage, and 138 patients (23.6%) in cT4 stage. There was no statistically significant difference in the detection rate of PCa/csPCa between TBx+6-core SBx and TBx+SBx (all P>0.999). Also, there was no statistically significant difference in the detection rate of PCa/csPCa between TBx and TBx+SBx in the cT2, cT3, and cT4 subgroups (PCa: P=0.203, P=0.250, P>0.999; csPCa: P=0.700, P=0.250, P>0.999). The missed diagnosis rate of SBx for PCa and csPCa was 2.1% (12/560) and 1.8% (10/549), and that of TBx for PCa and csPCa was 1.8% (10/560) and 1.4% (8/549), respectively. However, the detection rate of TBx+6-core SBx for PCa and csPCa was 100%. Compared with TBx+SBx, TBx and TBx+6-core SBx had a fewer number of cores and a higher detection rate per core (P < 0.001).@*CONCLUSION@#For patients with a PI-RADS score of 5, TBx and TBx+6-core SBx showed the same PCa/csPCa detection rates and a high detection rates per core as that of TBx+SBx, which can be considered as an optimal scheme for prostate biopsy.

Predicting and overcoming resistance to CDK9 inhibitors for cancer therapy

Abnormally activated CDK9 participates in the super-enhancer mediated transcription of short-lived proteins required for cancer cell survival. Targeting CDK9 has shown potent anti-tumor activity in clinical trials among different cancers. However, the study and knowledge on drug resistance to CDK9 inhibitors are very limited. In this study, we established an AML cell line with acquired resistance to a highly selective CDK9 inhibitor BAY1251152. Through genomic sequencing, we identified in the kinase domain of CDK9 a mutation L156F, which is also a coding SNP in the CDK9 gene. By knocking in L156F into cancer cells using CRISPR/Cas9, we found that single CDK9 L156F could drive the resistance to CDK9 inhibitors, not only ATP competitive inhibitor but also PROTAC degrader. Mechanistically, CDK9 L156F disrupts the binding with inhibitors due to steric hindrance, further, the mutation affects the thermal stability and catalytic activity of CDK9 protein. To overcome the drug resistance mediated by the CDK9-L156F mutation, we discovered a compound, IHMT-CDK9-36 which showed potent inhibition activity both for CDK9 WT and L156F mutant. Together, we report a novel resistance mechanism for CDK9 inhibitors and provide a novel chemical scaffold for the future development of CDK9 inhibitors.

Investigation on the carriage prevalence of Neisseria meningitidis in healthy population in Jiangsu Province in 2019 and 2020 / 中华预防医学杂志

In order to investigate carriage status and serum groups distribution of Neisseria meningitidis(Nm) among healthy population in Jiangsu Province, four counties were selected as monitoring sites by random sampling method for cross-sectional study. Throat swab specimens were collected from four monitoring sites in October to November 2019 and November to December 2020 for bacterial culture and Real-time PCR detection. Chi-square test was used to compare the positive rate of Neisseria meningitidis, and multiple logistic regression model was used to analyze the influencing factors of Neisseria meningitidis carrier rate. The results showed that among 1 512 samples, 57 strains of Nm were isolated, and the carrier rate was 3.77%. Serogroup B was the dominant group (36.84%), followed by un-known serogroups (33.33%), serogroup C was the third (17.54%), serogroup W135 and serogroup A were 7.02% and 5.26%, respectively. The carriage rate (8.60%) of 15-20 years old was significantly higher than others (1.77%-3.74%)(Pearson χ2=18.211, P<0.05). Region, age and immunization history were risk factors for Neisseria meningitidis carrier rate. In summary, the Nm carrier rate of healthy population in Jiangsu Province is relatively low, which indicates that the epidemic cases will continue to be sporadic in the future. However, the prevention and control of meningococcal epidemics on campus should be strengthened, and the monitoring of neisseria meningitidis group B should be maintained as it has become the dominant epidemic strain.

Mare's milk attenuates sodium dextran sulfate induced inflammation in mouse ulcerative colitis / 细胞与分子免疫学杂志

Objective To investigate the immunomodulatory effect of mare's milk on dextran sulfate sodium (DSS)-induced ulcerative colitis (UC) mice. Methods Kunming mice were randomly divided into a blank group(0.8 mL/day saline by gavage) and a DSS modeling group. After modeling, the DSS modeling group was further divided into a control group (0.8 mL/day saline), a salazosulfapyridine (SASP) treated group(430 mg/(kg.d)) and a mare's milk group(0.8 mL/day), with 16 mice in each group. After 10 days of gavage administration, HE staining was performed to observe colonic inflammation, and the disease activity index (DAI) and colonic mucosal damage index (CMDI) were scored. ELISA was used to determine the levels of interleukin 1β (IL-1β), IL-6, and IL-10 in mouse colonic tissues, and flow cytometry was used to detect the percentages of CD4+ and CD8+ T lymphocytes in peripheral blood. Results Compared to the blank group, all indexes in mice of the control group indicated that DSS successfully induced UC. Compared to the control group, colon shortening in UC mice was attenuated in the mare's milk group; inflammation and ulcer formation in colonic tissues were inhibited; DAI and CMDI scores were lowere; IL-1β and IL-6 levels in mouse colonic tissues were significantly reduced; IL-10 levels were increased and the CD4+/CD8+ T cell ratio was reduced. Conclusion Mare's milk can inhibit the inflammation of DSS-induced UC mice through immune regulation.

Remodeling of tumor stroma combined with photothermal therapy in the treatment of triple-negative breast cancer / 中华肿瘤杂志

Objective: Polyethylene glycol-modified gold nanostar particles (GNS-PEG) were constructed to investigate whether the degradation of extracellular matrix in triple-negative breast cancer could improve the tumor delivery of GNS-PEG and enhance the efficacy of photothermal therapy. Methods: GNS-PEG were constructed and characterized for physicochemical properties as well as photothermal properties. At the cellular level, the cytotoxicity of halofuginone (HF) and the effect of photothermal therapy were detected. Mouse model of triple negative breast cancer was established by subcutaneous inoculation of 4T1 cells in BALB/c nude mice. Five injections of HF were given via tail vein (HF group), and tumor sections were stained with Masson stain and immunohistochemical staining for transforming growth factor β1 (TGFβ1), α-smooth muscle actin (α-SMA) and CD31 to observe the effect of tumor stromal degradation. Five injections of HF via tail vein followed by GNS-PEG (HF+ GNS-PEG group) were applied to determine the content of gold in tumor tissues by inductively coupled plasma mass spectrometry. The tumor sites of the mice in the GNS-PEG and HF+ GNS-PEG groups were irradiated with NIR laser and the temperature changes were recorded with an IR camera. The tumour growth and weight changes of mice in each group were observed. Ki-67 immunohistochemical staining, TdT-mediated dUTP nick-end labeling and HE staining were performed on tumor tissue sections from each group to observe tumor proliferation, apoptosis and necrosis. HE staining was performed on heart, liver, spleen, lung and kidney tissues from each group to observe the morphological changes of cells. Results: GNS-PEG nanoparticles showed a multi-branched structure with a particle size of 73.5±1.4 nm. The absorption peak of GNS was 810 nm, which is in the near infrared region. The photothermal conversion rate of GNS-PEG was up to 79.3%, and the photothermal effect could be controlled by the laser energy. HF has a concentration-dependent cytotoxicity, with a cell survival rate being as low as (22.8±2.6)% at HF concentration of up to 1 000 nmol/L. The photothermal effect of GNS-PEG was significant in killing tumor cells, with a cell survival rate of (32.7±5.2)% at the concentration of 25 pmol/L. The collagen area fraction, TGFβ1 integrated optical density and α-SMA integrated optical density in the tumor tissues of mice in the HF group were (2.1±0.2)%, 3.1±0.4 and 5.2±1.9, respectively, which were lower than those of the control group (all P<0.01), and the vessel diameter was 8.6±2.9 μm, which was higher than that of the control group (P<0.05). In the HF+ GNS-PEG group, the concentration of gold in tissues was 52.4 μg/g, higher than that in the GNS-PEG group (15.9 μg/g, P<0.05). After laser irradiation, the temperature of the tumor site in the HF+ GNS-PEG group was significantly higher than that in the GNS-PEG group. At the 4th minute, the temperatures of the tumor site in the GNS-PEG and HF+ GNS-PEG groups were 51.5 ℃ and 57.7 ℃ respectively; the tumor volume in the HF+ GNS-PEG group was effectively suppressed. The body weights of the mice in each group did not change significantly during the monitoring period. No significant abnormalities were observed in the main organs of the mice in the GNS-PEG group, but some hepatocytes in the HF and HF+ GNS-PEG groups showed edema and degeneration. Conclusion: The remodeling of extracellular matrix in triple-negative breast cancer could significantly improve the intratumoral delivery of GNS-PEG and thus achieve better photothermal therapy effect.

Study on the association between air pollution and respiratory disease of primary school students in Chongqing City / 中华预防医学杂志

To analyze the association between exposure to air pollution and respiratory disease of primary school students in Chongqing City. Eight districts and counties were randomly selected based on the air pollution situation in Chongqing City. In each selected district and county, one primary school was randomly selected. A questionnaire survey was conducted on all primary school students in Grades 3-5 by the end of 2019. Air quality data from the nearest environmental monitoring sites were collected. A logistic regression model was used to analyze the impact of the living environment, lifestyle and air pollution on the respiratory disease of surveyed students. This study included 5 918 primary school students, with a prevalence rate of respiratory disease of 21.54%. The prevalence rates of boys and girls were 23.38% and 19.59%, respectively. The average Air quality index (AQI) of the surveyed school was 67, and the rates of exceeding standards of PM10, PM2.5, NO2 and O3 were 1.16%, 6.92%, 0.99% and 5.65%, respectively. The level of SO2 and CO did not exceed the standard. After adjusting for relevant factors, logistic regression analysis showed that primary school students in areas with high exposure to air pollution (OR=2.52), using air pollution related-chemicals at home (OR=1.47), passive smoking (OR=1.27), and keeping pets at home (OR=1.18) had a higher risk of respiratory disease (all P<0.05). In addition, the average annual values of AQI (OR=1.18), PM10 (OR=1.20), PM2.5 (OR=1.35), and NO2 (OR=1.11) increased the risk of respiratory diseases in primary school students (all P<0.05). In conclusion, the respiratory disease of primary school students in Chongqing City is related to the living environment, behavior habits and ambient air quality. The increased exposure concentration of PM10, PM2.5 and NO2 in air pollutants can lead to an increased risk of respiratory disease among primary school students.

Study on formulation and revision of standard limits for radon in "Standards for indoor air quality (GB/T 18883-2022)" in China / 中华预防医学杂志

Public exposure to radon has attracted increasing public concern. The newly issued "Standards for indoor air quality (GB/T 18883-2022)" has revised the radiological parameters of radon. This study analyzed and discussed the relevant technical contents about the derivation of radon limit, including the distribution level for indoor radon, exposure pathway, health effects, and the process for establishing the standard limits. Specific implementation and evaluation suggestions are also proposed.

Study on formulation and revision of detection methods of "Standards for indoor air quality (GB/T 18883-2022)" in China / 中华预防医学杂志

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

Remodeling of tumor stroma combined with photothermal therapy in the treatment of triple-negative breast cancer / 中华肿瘤杂志

Objective: Polyethylene glycol-modified gold nanostar particles (GNS-PEG) were constructed to investigate whether the degradation of extracellular matrix in triple-negative breast cancer could improve the tumor delivery of GNS-PEG and enhance the efficacy of photothermal therapy. Methods: GNS-PEG were constructed and characterized for physicochemical properties as well as photothermal properties. At the cellular level, the cytotoxicity of halofuginone (HF) and the effect of photothermal therapy were detected. Mouse model of triple negative breast cancer was established by subcutaneous inoculation of 4T1 cells in BALB/c nude mice. Five injections of HF were given via tail vein (HF group), and tumor sections were stained with Masson stain and immunohistochemical staining for transforming growth factor β1 (TGFβ1), α-smooth muscle actin (α-SMA) and CD31 to observe the effect of tumor stromal degradation. Five injections of HF via tail vein followed by GNS-PEG (HF+ GNS-PEG group) were applied to determine the content of gold in tumor tissues by inductively coupled plasma mass spectrometry. The tumor sites of the mice in the GNS-PEG and HF+ GNS-PEG groups were irradiated with NIR laser and the temperature changes were recorded with an IR camera. The tumour growth and weight changes of mice in each group were observed. Ki-67 immunohistochemical staining, TdT-mediated dUTP nick-end labeling and HE staining were performed on tumor tissue sections from each group to observe tumor proliferation, apoptosis and necrosis. HE staining was performed on heart, liver, spleen, lung and kidney tissues from each group to observe the morphological changes of cells. Results: GNS-PEG nanoparticles showed a multi-branched structure with a particle size of 73.5±1.4 nm. The absorption peak of GNS was 810 nm, which is in the near infrared region. The photothermal conversion rate of GNS-PEG was up to 79.3%, and the photothermal effect could be controlled by the laser energy. HF has a concentration-dependent cytotoxicity, with a cell survival rate being as low as (22.8±2.6)% at HF concentration of up to 1 000 nmol/L. The photothermal effect of GNS-PEG was significant in killing tumor cells, with a cell survival rate of (32.7±5.2)% at the concentration of 25 pmol/L. The collagen area fraction, TGFβ1 integrated optical density and α-SMA integrated optical density in the tumor tissues of mice in the HF group were (2.1±0.2)%, 3.1±0.4 and 5.2±1.9, respectively, which were lower than those of the control group (all P<0.01), and the vessel diameter was 8.6±2.9 μm, which was higher than that of the control group (P<0.05). In the HF+ GNS-PEG group, the concentration of gold in tissues was 52.4 μg/g, higher than that in the GNS-PEG group (15.9 μg/g, P<0.05). After laser irradiation, the temperature of the tumor site in the HF+ GNS-PEG group was significantly higher than that in the GNS-PEG group. At the 4th minute, the temperatures of the tumor site in the GNS-PEG and HF+ GNS-PEG groups were 51.5 ℃ and 57.7 ℃ respectively; the tumor volume in the HF+ GNS-PEG group was effectively suppressed. The body weights of the mice in each group did not change significantly during the monitoring period. No significant abnormalities were observed in the main organs of the mice in the GNS-PEG group, but some hepatocytes in the HF and HF+ GNS-PEG groups showed edema and degeneration. Conclusion: The remodeling of extracellular matrix in triple-negative breast cancer could significantly improve the intratumoral delivery of GNS-PEG and thus achieve better photothermal therapy effect.

Study on the association between air pollution and respiratory disease of primary school students in Chongqing City / 中华预防医学杂志

To analyze the association between exposure to air pollution and respiratory disease of primary school students in Chongqing City. Eight districts and counties were randomly selected based on the air pollution situation in Chongqing City. In each selected district and county, one primary school was randomly selected. A questionnaire survey was conducted on all primary school students in Grades 3-5 by the end of 2019. Air quality data from the nearest environmental monitoring sites were collected. A logistic regression model was used to analyze the impact of the living environment, lifestyle and air pollution on the respiratory disease of surveyed students. This study included 5 918 primary school students, with a prevalence rate of respiratory disease of 21.54%. The prevalence rates of boys and girls were 23.38% and 19.59%, respectively. The average Air quality index (AQI) of the surveyed school was 67, and the rates of exceeding standards of PM10, PM2.5, NO2 and O3 were 1.16%, 6.92%, 0.99% and 5.65%, respectively. The level of SO2 and CO did not exceed the standard. After adjusting for relevant factors, logistic regression analysis showed that primary school students in areas with high exposure to air pollution (OR=2.52), using air pollution related-chemicals at home (OR=1.47), passive smoking (OR=1.27), and keeping pets at home (OR=1.18) had a higher risk of respiratory disease (all P<0.05). In addition, the average annual values of AQI (OR=1.18), PM10 (OR=1.20), PM2.5 (OR=1.35), and NO2 (OR=1.11) increased the risk of respiratory diseases in primary school students (all P<0.05). In conclusion, the respiratory disease of primary school students in Chongqing City is related to the living environment, behavior habits and ambient air quality. The increased exposure concentration of PM10, PM2.5 and NO2 in air pollutants can lead to an increased risk of respiratory disease among primary school students.

Study on formulation and revision of standard limits for radon in "Standards for indoor air quality (GB/T 18883-2022)" in China / 中华预防医学杂志

Public exposure to radon has attracted increasing public concern. The newly issued "Standards for indoor air quality (GB/T 18883-2022)" has revised the radiological parameters of radon. This study analyzed and discussed the relevant technical contents about the derivation of radon limit, including the distribution level for indoor radon, exposure pathway, health effects, and the process for establishing the standard limits. Specific implementation and evaluation suggestions are also proposed.

Study on formulation and revision of detection methods of "Standards for indoor air quality (GB/T 18883-2022)" in China / 中华预防医学杂志

The formulation and revision of the detection methods of indoor air quality standards is an important, rigorous and delicate endeavor. This paper introduced the formulation and revision of the detection methods of the standards for indoor air quality (GB/T 18883-2022), focusing on the revision process, revision principles, main adjustments and technical points of some key indicators to facilitate users to better understand and apply the detection methods in standards for indoor air quality (GB/T 18883-2022).

A nomogram for predicting postoperative pulmonary infec-tion in gastric cancer patients / 中国现代普通外科进展

Objective:To identifying risk factors of postoperative pulmonary infection(POI)in gastric cancer(GC)patients as well as generating an effective nomogram for the POI.Methods:Pa-tients with gastric cancer after surgery from 1st January 2010 to 31st December 2020 were retro-spectively analysed.Their clinical and pathological data were collected.Multiple logistic regression analysis was conducted to identify risk factors for POI and to generate the nomogram prediction model.Predictive accuracy,discriminatory capability,and clinical usefulness were evaluated by cali-bration curves,concordance index(C-index),and decision curve analysis(DCA).Results:Multivari-ate regression analysis revealed that age,smoking,chronic respiratory diseases,laparoscopic surgery,intraoperative blood loss and lung function exercise compliance were independent prognos-tic factors for POI in GC patients.The nomogram had a Cindex of 0.878(95％CI:0.801～0.956).The calibration curves showed good consistency between actual and nomogram-predicted probabilities.The area under the curve(AUC)was 0.878,while the cutoff value was-2.088 with a sensitivity of 80.6％and a specifificity of 82.9％.DCA showed that the nomogram had better clinical usefulness.Conclusions:The present study provides a nomogram developed with perioperative features to predict the incidence of POI in GC patients.