OBJECTIVE To prepare C-phycocyanin nanoparticles （CPC-NPs） and evaluate the in vitro mechanism of CPC- NPs on acute lung injury induced by lipopolysaccharide （LPS） combined with seawater. METHODS Ion crosslinking method was used to prepare CPC-NPs using CPC as the drug， carboxymethyl chitosan （CMCS） as the carrier， and CaCl2 as the crosslinking agent. The basic characterization of CPC-NPs was carried out. Mouse alveolar type Ⅱ epithelial cells MLE-12 and macrophages RAW264.7 were divided into 7 groups： normal group （Con group）， model group （Mod group）， blank NPs group， CPC-NPs 30， 60， 120 and 240 μg/mL groups. Except for the Con group， all other groups were treated with a combination of 10 μg/mL LPS and 25% seawater for 6 hours. After modeling， each treatment group was treated with corresponding drugs for 24 hours. The levels of malondialdehyde （MDA）， total antioxidant capacity （T-AOC）， superoxide dismutase （SOD）， catalase （CAT）， and glutathione peroxidase （GSH-Px） in MLE-12 cells， as well as the expression levels of B-cell lymphoma-2 （Bcl-2）， Bcl-2 associated X protein （Bax）， caspase-3 protein and mRNA， CAT and glutathione S-transferase （GST） mRNA were determined. The levels of interleukin- 1β （IL-1β）， tumor necrosis factor-α （TNF-α） and IL-6 in RAW264.7 cells， as well as the expression levels of NOD-like receptor thermal protein domain associated protein 3 （NLRP3）， cleaved caspase-1 protein， and mRNA expressions of IL-1β，TNF-α， IL-6 and inducible nitric oxide synthase （iNOS） were all detected. RESULTS The prepared CPC-NPs had particle size of （675.69±64.58） nm， Zeta potential of （－20.11± E-mail：zhangleifang1986@163.com 0.98） mV， polydispersity coefficient of 0.455±0.010 （n＝3）；entrapment efficiency of 35.60%， and drug loading of 16.13%；CPC-NPs had regular spherical shapes， where the drug could be sustainably released for more than 30 hours. Compared with Mod group， the levels of T-AOC， SOD， CAT （excluding the 30 μg/mL group of CPC-NPs） and GSH-Px， mRNA expressions of CAT and GST， as well as the Bcl-2/Bax protein ratio and mRNA ratio were significantly increased in MLE-12 cells of different concentration groups of CPC-NPs， while MDA levels and caspase-3 protein and mRNA expression were significantly reduced （P＜0.01 or P＜0.05）. Compared with Mod group， the levels of IL-1β， TNF-α and IL-6， NLRP3 and cleaved-caspase-1 protein expressions， as well as the mRNA expressions of IL-1β， TNF-α， IL-6 and iNOS in RAW264.7 cells of different concentration groups of CPC-NPs were significantly reduced （P＜0.01 or P＜0.05）. CONCLUSIONS CPC-NPs with lung targeting and sustained release property were prepared successfully， which can alleviate acute lung injury induced by LPS combined with seawater through antioxidant stress， inhibiting cell apoptosis and inflammatory response.

Objective To investigate the effect and mechanism of emodin on focal cerebral ischemia in rats based on myeloid differentiation factor 88(MyD88)/extracellular signal-regulated kinase(ERK)pathway and nuclear factor-κB(NF-κB)nuclear translocation.Methods SD rats were randomly divided into sham operation group,model group and emodin group,with six rats in each group.The rat model of transient middle cerebral artery occlusion(tMCAO)was established by middle cerebral artery embolization.Rats in the emodin group were given 40 mg·kg-1 emodin by gavage for three times at 72,48 and 24 hours before modeling.At 24 hours after modeling,the neurological function of rats was scored.TTC staining was used to detect the area of cerebral infarction.HE staining was used to observe the morphological changes of brain tissue.The mRNA expression levels of MyD88 and tumor necrosis factor-α(TNF-α)in brain tissue were detected by RT-qPCR.The expression levels of MyD88,ERK,p-ERK and TNF-α in brain tissue were detected by Western Blot.The protein expression of NF-κB in brain tissue was detected by immunofluorescence.Results Compared with the sham operation group,the neurological function score of the model group was significantly increased(P＜0.01),and the cerebral infarction area was significantly increased(P＜0.01).In the cortical area of the ischemic penumbra,cell necrosis,abnormal cell morphology,nuclear fragmentation and atrophy,and the number of cells decreased significantly;the mRNA expression levels of MyD88 and TNF-α in brain tissue were significantly increased(P＜0.01,P＜0.001),the protein levels of MyD88,p-ERK/ERK and TNF-α were significantly increased(P＜0.05,P＜0.01,P＜0.001),and the proportion of NF-κB into nuclear cells was significantly increased(P＜0.001).Compared with the model group,the neurological function score of rats in the emodin group was significantly decreased(P＜0.05),and the area of cerebral infarction was significantly reduced(P＜0.05).The number and morphology of neurons in the ischemic penumbra cortex were restored to a certain extent.The mRNA expression levels of MyD88 and TNF-α in brain tissue were significantly decreased(P＜0.05,P＜0.01),the protein levels of MyD88,p-ERK/ERK and TNF-α were significantly decreased(P＜0.05),and the proportion of NF-κB into nuclear cells was significantly decreased(P＜0.001).Conclusion Emodin has a preventive and protective effect on rats with focal cerebral ischemia,which may be related to its inhibition of MyD88 activation,ERK phosphorylation and NF-κB nuclear translocation,and then down-regulation of inflammatory cascades and secretion of pro-inflammatory factors such as TNF-α,thereby exerting anti-inflammatory effects.

Objective To find out the prevalence of antiretroviral therapy(ART)drugs among treponema pallidum(TP)antibody(anti-TP)positive blood donors in Shenzhen,and to assess the blood safety risks brought about by the new trends of human immunodeficiency virus(HIV)diagnosis and treatment.Methods A stratified random sampling method was used to select 60 repeat blood donors(negative control group)who passed blood screening in Shenzhen from March 2019 to January 2023,and 3 people who regularly took known ART drugs were named positive control group,358 anti-TP positive/anti-HIV negative blood do-nors were named experimental group 1,20 anti-TP positive/anti-HIV positive blood donors were named ex-perimental group 2.The liquid chromatography-mass spectrometry(HPLC-MS/MS)was applied to detect the concentration of 8 ART drugs in plasma samples of each group,and the use of ART drugs was analyzed.Re-sults After the positive control group's plasma was diluted with a 1:6 dilution mixture,the ART drugs could still be detected.The positive mixed plasma samples of 1:6 people in Group 1 and Group 2 were split and validation,one ART drug positive sample was detected in Group 2,which was positive for anti-HIV,pro-tein immunoblotting,and HIV RNA.The detection rate of ART drugs in anti-TP positive blood donors was 0.26％,0.00％in Group 1 and 4.00％in Group 2.Conclusion The use of ART drugs has been found among anti-TP positive blood donors in Shenzhen,and people with HIV infection and high-risk sexual behavior are more likely to use antiretroviral drugs.

【Objective】 To explore the the potential risks of antiretroviral therapy(ART) drugs on blood safety among blood donors in Shenzhen. 【Methods】 High pressure liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS) was used to measure ART drugs concentrations in the plasma of regular blood donors (negative control group, n=86) and anti-HIV positive individuals (experimental group, n=98, detected from approximately 440 000 blood donors during 2019—2023). The baseline plasma concentrations of ART drugs in the negative control group were clarified, and the impact of ART drugs on blood safety was analyzed. 【Results】 The baseline concentrations of ART drugs were not detected in 86 samples of negative control group. Four positive ART drugs samples were detected in 1∶2 pooled plasma samples of 98 anti-HIV positive blood donors plasma in the resolution test. The ART positive rate of anti-HIV positive donors was 4.08%, with tenofovir, lamivudine and efavirenz detected in three blood donors and lamivudine, lopinavir, ritonavir and zidovudine detected in one blood donor. 【Conclusion】 ART drugs were found among anti-HIV positive blood donors in Shenzhen. Additional research is needed to investigate the motivation of these specific donors, so as to ascertain the groups most susceptible to potential risks, and guarantee blood safety.

【Objective】 To analyze the results of different methods for reactive samples screened by the enzyme linked immunosorbent assay (ELISA) against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in blood donors. 【Methods】 From March to April 2020, a total of 8 632 blood samples in Shenzhen were screened for SARS-CoV-2 total antibodies (TAb, including IgG, IgM, IgA) in plasma using ELISA(PC group), the antibody reactivity samples and their follow up plasma samples (FC group), and samples of disease control group(DC group) from January to April 2020 were detected using the following methods: 1) ELISA method for detecting IgG, IgM, and (or without detection) TAb; 2) pseudovirus neutralizing antibody test(pVNT); 3) western blot (WB) of SARS-CoV-2 antibody. The negative control group(NC group) from February to April 2020 performed ELISA and WB testing. 【Results】 Among the 34 total antibody positive samples, 2 were positive for pVNT test, and the total antibody, IgG and WB in the initial screening and tracking testing were positive. Thereafter, it was determined to be confirmed positive. The other 2 cases were positive for pVNT test, while the samples with positive WB results were in the follow-up stage. The TAb, IgG, and pVNT results did not conform to the dynamic evolution of antibodies, and cannot be determined as confirmed positive. 【Conclusion】 The infection status of antibody reactivity samples screened by SARS-CoV-2 ELISA can be judged by the logic of pVNT, WB and the dynamic change of antibody.

【Objective】 To analyze the SARS-CoV-2 detection results among blood donors in different periods of COVID-19 pandemic control in Shenzhen and assess the antibody levels and infection status of blood donors in different periods, so as to provide reference for subsequent blood testing strategies. 【Methods】 A total of 4 768 plasma samples of blood donors were subjected to pooled testing by nucleic acid testing(NAT) with 8 samples per pool. Additionally, these samples were subjected to a 1000-fold dilution, and the detection of SARS-CoV-2 total antibody was performed by enzyme-linked immunosorbent assay (ELISA). The 4 768 plasma samples were collected from blood donors at different time points in Shenzhen, with inquiries made to determine whether donors during the COVID-19 pandemic were in the convalescence. The antibody positive rates in blood screening samples during different periods of the pandemic and samples from individuals in the convalescence of COVID-19 infection were analyzed. Furthermore, the antibody levels were examined for differences based on gender, age, and blood type. 【Results】 All 4 768 plasma samples from blood donors were negative by NAT, while 2 342 samples were detected positive by the SARS-CoV-2 total antibody detection, with a positive rate of 49.1%. These samples from four periods (September 30 to October 3, 2022; November 3 to 6, 2022; December 27 to 31, 2022; January 6 to 18, 2023) were subjected to a 1 000-fold dilution for COVID-19 antibody detection, and the positive rates were 21.3%, 15.8%, 65.9%, and 93.9%, respectively. 【Conclusion】 The prevalence of COVID-19 antibodies among blood donors in Shenzhen during different periods of the pandemic varied significantly. There was no difference in antibody prevalence among different genders and blood types, while younger individuals exhibited a higher prevalence of antibodies. The risk of COVID-19 transmission through blood transfusion was found to be extremely low.

【Objective】 To establish a magnetic bead enrichment strategy for the detection of human immunodeficiency virus deoxyribonucleic acid (HIV DNA) in peripheral blood, and to verify the improvement of the sensitivity of this method for the detection of HIV DNA in HIV infected patients after early antiretrovital treatment (ART). 【Methods】 Peripheral whole blood was collected at 4 timepoints in one ART HIV window period (WP) patient. Peripheral blood mononuclear cells (PBMCs) were isolated on a Ficoll gradient. CD4⁺ T lymphocytes were enriched from total PBMCs by negative sorting. HIV DNA concentration in magnetic beads enriched group and whole blood group was detected by HIV DNA detection kit. 【Results】 CD4⁺ T cells were isolated by magnetic beads and identified by FCM for purity at (96.4 ± 2.6)%. The viability was (95.9 ± 2.9)%, as demonstrated by trypan blue staining. The person on continued ART treatment in this study had significantly greater reduction in HIV viral load and undetectable HIV plasma RNA at follow up timepoint 4. No HIV DNA was detected in the whole blood group at all 4 timepoints. The quantitative results of HIV DNA in the CD4⁺ T lymphocyte group of the magnetic bead enrichment group were 73.4, 429.3, 137.1, 449.9 copies/10⁶ CD4⁺ T cell′s respectively. 【Conclusion】 The magnetic bead enrichment method can be more sensitive in detecting the limit low copy HIV DNA in blood samples, and provide early confirmatory data for HIV WP infection and breakthrough infection after ART treatment.

ObjectiveTo investigate the therapeutic effect of the water extract of Zanthoxylum bungeanum aqueous extract（ZBAE）on rheumatoid arthritis. MethodThe sixty SD rats were divided into normal group， model group ［complete Freund's adjuvant （CFA）， 10 mg·kg^-1］， methotrexate（MTX） group （0.25 mg·kg^-1）， low -， medium -， and high-dose ZBAE groups （90， 180， 360 mg·kg^-1）. The rats in MTX group were given intraperitoneal injection for two weeks， three times a week， and the rats in ZBAE group were administrated for 14 days. The swelling of the ankle joint and body weight were observed， and arthritis scores were also performed. Computed tomography （CT）， hematoxylin-eosin （HE） staining and safranine-O and fast green staining were used to observe the effect of ZBAE on synovial hyperplasia and bone protection. Cell counting kit-8（CCK-8）method was used to detect the proliferation of the RA-FLSs cells treated with ZBAE. According to the results of CCK-8 experiment， the optimal concentration and time of administration were determined， blank group， low -， medium -， and high-dose ZBAE groups （0.08，0.10，0.12 g·L^-1） were set up. The cell cycle distribution and apoptosis rate were analyzed by flow cytometry，the migration ability of RA-FLSs cells was examined by scratch test. Western blot was used to detect the effect of ZBAE on phosphatidylinositol 3-kinase （PI3K）， protein kinase B （Akt）， cyclin-dependent kinase 2 （CDK2）， Cyclin A and phosphorylated PI3K， Akt （p-PI3K，p-Akt） protein expression in RA-FLSs cells. ResultCompared with the normal group，joint swelling index and arthritis score were increased in the model group （P<0.05），the bone of the ankle was seriously damaged， and there was obvious synovial hyperplasia. Compared with the model group， the ZBAE group could significantly reduce the joint swelling index （P<0.05）， inhibit synovial hyperplasia and cartilage destruction. In vitro study showed that compared with the blank group， ZBAE could inhibit the migration of RA-FLSs （P<0.05）， promoted cell apoptosis （P<0.05）， and acted on RA-FLSs cells in S phase to inhibit cell proliferation. Moreover， the result of Western blot showed that compared with the blank group， the expression of p-PI3K， p-Akt， CDK2 and Cyclin A proteins were significantly decreased in the high dose group of ZBAE （P<0.05）. ConclusionThese results suggest that ZBAE has a therapeutic effect on rheumatoid arthritis by inhibiting synovial hyperplasia， promoting synovial apoptosis and inhibiting its migration.

【Objective】 To assess three severe acute respiratorysyndrome coronavirus 2 (SARS-CoV-2) enzyme linked immunosorbent assays (ELISA) and one pseudotype lentivirus-based neutralization test (ppNAT) in detecting the convalescent plasma antibody levles from COVID-19. 【Methods】 30 COVID-19 convalescent plasma samples were screened for antibodies against SARS-CoV-2 using three kinds of SARS-CoV-2 ELISA reagents and one ppNAT test in Shenzhen. The controls consisted of plasma samples from 32 healthy blood donors in February 2019. The diagnostic efficacy analysis of various SARS-CoV-2 ELISA reagents was performed using real-time fluorescent Polymerase Chain Reaction (RT-PCR). We also analyzed correlation between different immunological reagents and the age, gender, hospitalization, and severity of illness. 【Results】 The positive yielding rate of ppNAT and three kinds of IgG ELISA was higher than that of IgM ELISA. The positive yielding rates of three kinds of IgG ELISA were 100%(30/30), 93.33%(28/30), and 96.67%(29/30) respectively, while the yielding rates in control group were all 0. The positive yielding rate of three IgM ELISAs were 93.33%(28/30), 70%(21/30)and 46.67% (14/30). All the cases from negative control group were negative for IgG and IgM. Pearson correlation coefficient was calculated; there was a strong correlation between ELISA reagent 2 IgG and ELISA reagent 3 IgG (r=0.765, P<0.01). The correlation between ppNAT, ELISA reagent 3 IgG and the age of recovered patients was 0.422 and 0.385, respectively (P<0.05), while no significant correlation was found between the duration of hospitalization, severity of illness, gender and antibody signal/cutoff (S/CO) (P>0.05). 【Conclusion】 In the convalescent plasma with nucleic acid confirmed covid-19, the yielding rates of different IgM antibodies varied greatly. Antibody levels were influenced by age to some extent.

Background N-nitrosodimethylamine (NDMA), a new disinfection by-product in drinking water, has attracted extensive attention due to its high detection rate and concentration. Objective To investigate the concentration of NDMA in drinking water in Nanjing situated in the lower Yangtze River Basin of China, and to evaluate associated human health risk. Methods In dry period (January–March) and wet period (July–September) of 2021, raw water, finished water, and tap water from 16 centralized water treatment plants in Nanjing were collected to detect the concentration of NDMA in water samples by solid phase extraction and gas chromatography-triple quadrupole mass spectrometry with programmable temperature vaporizer-based large volume injection. The concentrations of NDMA in water samples of different water types, water periods, and disinfection methods were analyzed, and the daily exposure levels and carcinogenic risk values of NDMA in drinking water of different exposure routes and different exposed populations were calculated. Monte Carlo simulation was implemented with Crystal Ball 11 software to establish a health risk assessment model and conduct sensitivity analysis. Results A total of 61 drinking water samples were collected in Nanjing, and NDMA was positive in all the water samples, with concentrations ranging from 1.36 to 25.65 ng·L⁻¹ and an overall average concentration of (8.00±4.06) ng·L⁻¹. There were no statistically significant differences in the average concentrations of NDMA among raw water, finished water, and tap water samples (F=2.875, P=0.064), between wet season and dry season (t=−0.855, P=0.397), or among different disinfection methods by liquid chlorine, sodium hypochlorite, and chlorine dioxide (F=0.977, P=0.385). The results of health risk assessment showed that the average carcinogenic risk of NDMA and its P₉₅ were 5.95×10⁻⁶ and 1.12×10⁻⁵ respectively for oral intake of drinking water, and the values for dermal contact were both lower than 1.00×10⁻⁶. The mean carcinogenic risks of exposure to drinking water NDMA in children, adolescents, and adults were 1.84×10⁻⁶, 8.27×10⁻⁷, and 3.28×10⁻⁶, respectively. The results of sensitivity analysis showed that the contributions of daily drinking water volume and NDMA concentration in drinking water to the calculated health risk were high, and the contribution of body weight was negative. Conclusion There is a potential carcinogenic risk of NDMA in the drinking water of Nanjing section of the lower Yangtze River Basin，but it is within the acceptable range.