Background::Total human immunodeficiency virus (HIV) DNA and integrated HIV DNA are widely used markers of HIV persistence. Droplet digital polymerase chain reaction (ddPCR) can be used for absolute quantification without needing a standard curve. Here, we developed duplex ddPCR assays to detect and quantify total HIV DNA and integrated HIV DNA.Methods::The limit of detection, dynamic ranges, sensitivity, and reproducibility were evaluated by plasmid constructs containing both the HIV long terminal repeat (LTR) and human CD3 gene (for total HIV DNA) and ACH-2 cells (for integrated HIV DNA). Forty-two cases on stable suppressive antiretroviral therapy (ART) were assayed in total HIV DNA and integrated HIV DNA. Correlation coefficient analysis was performed on the data related to DNA copies and cluster of differentiation 4 positive (CD4 +) T-cell counts, CD8 + T-cell counts and CD4/CD8 T-cell ratio, respectively. The assay linear dynamic range and lower limit of detection (LLOD) were also assessed. Results::The assay could detect the presence of HIV-1 copies 100% at concentrations of 6.3 copies/reaction, and the estimated LLOD of the ddPCR assay was 4.4 HIV DNA copies/reaction (95% confidence intervals [CI]: 3.6-6.5 copies/reaction) with linearity over a 5-log 10-unit range in total HIV DNA assay. For the integrated HIV DNA assay, the LLOD was 8.0 copies/reaction (95% CI: 5.8-16.6 copies/reaction) with linearity over a 3-log 10-unit range. Total HIV DNA in CD4 + T cells was positively associated with integrated HIV DNA ( r = 0.76, P <0.0001). Meanwhile, both total HIV DNA and integrated HIV DNA in CD4 + T cells were inversely correlated with the ratio of CD4/CD8 but positively correlated with the CD8 + T-cell counts. Conclusions::This ddPCR assay can quantify total HIV DNA and integrated HIV DNA efficiently with robustness and sensitivity. It can be readily adapted for measuring HIV DNA with non-B clades, and it could be beneficial for testing in clinical trials.

Background::Clinical opportunistic screening is a cost-effective cancer screening modality. This study aimed to establish an easy-to-use diagnostic model serving as a risk stratification tool for identification of individuals with malignant gastric lesions for opportunistic screening.Methods::We developed a questionnaire-based diagnostic model using a joint dataset including two clinical cohorts from northern and southern China. The cohorts consisted of 17,360 outpatients who had undergone upper gastrointestinal endoscopic examination in endoscopic clinics. The final model was derived based on unconditional logistic regression, and predictors were selected according to the Akaike information criterion. External validation was carried out with 32,614 participants from a community-based randomized controlled trial.Results::This questionnaire-based diagnostic model for malignant gastric lesions had eight predictors, including advanced age, male gender, family history of gastric cancer, low body mass index, unexplained weight loss, consumption of leftover food, consumption of preserved food, and epigastric pain. This model showed high discriminative power in the development set with an area under the receiver operating characteristic curve (AUC) of 0.791 (95% confidence interval [CI]: 0.750–0.831). External validation of the model in the general population generated an AUC of 0.696 (95% CI: 0.570–0.822). This model showed an ideal ability for enriching prevalent malignant gastric lesions when applied to various scenarios.Conclusion::This easy-to-use questionnaire-based model for diagnosis of prevalent malignant gastric lesions may serve as an effective prescreening tool in clinical opportunistic screening for gastric cancer.

After onset of acute ischemic stroke, nerve cells undergo ischemic necrosis, release endogenous damage related pattern molecules, which activate microglia and astrocytes, and lead to immune inflammatory responses. At the same time, it attracts and chemotactically guide peripheral blood immune cells to infiltrate brain tissue through the damaged blood-brain barrier, further exacerbating brain injury. Studies have shown that the peripheral blood immune cells are closely associated with the outcome of acute ischemic stroke. This article summarizes the mechanism of peripheral immune cells in ischemic brain injury, their correlation with clinical outcome, and possible intervention measures.

Objective To investigate the expression and prognostic value of spindle and kinetochore-associated complex subunit 2(SKA2)in cervical cancer tissues,as well as its impact on the proliferation,migration and invasion of cervical cancer cells.Methods The expression of SKA2 in cervical cancer tissues was analyzed by bioinformatics database and immunohistochemical SP method,and the relationship between SKA2 expression level and clinicopathological features of cervical cancer patients and its prognostic value was analyzed.The mRNA expression of SKA2 in human normal cervical cells(HcerEpic)and cervical cancer cells(HeLa,SiHa,CaSki,C-33A)was detected by RT-qPCR.Cervical cancer cells SiHa with higher SKA2 expression level was selected for further study.SiHa cell model with down-regulated SKA2 expression was constructed,and its knockdown effect was verified.Cell proliferation capacity was detected by CCK-8 method,cell migration capacity was detected by cell scratch wound healing assay,and cell migration and invasion capacity was detected by Transwell assay.Results Compared with normal cervical tissues and cells,the expression levels of SKA2 mRNA and protein were higher in cervical cancer tissues and cells,and the differences were statistically significant(P<0.05).High SKA2 expression was associated with FIGO staging in patients with cervical cancer.Furthermore,SKA2 knockdown could inhibit the proliferation,migration and invasion of SiHa cells in cervical cancer(P<0.05).Conclusion SKA2 is up-regulated in cervical cancer tissues and cells,and can promote the proliferation,migration and invasion of cervical cancer cells.The expression level of SKA2 is associated with the progression of cervical cancer,and the prognosis of cervical cancer patients with high SKA2 expression is worse.

Objective This study aimed to explore the diagnostic concordance of fractional flow reserve(FFR)and quantitative flow ratio(QFR)and the characteristics affecting this concordance.Methods Patients with non-acute myocardial infarction admitted to the Department of Cardiology,Peking University Third Hospital between January 2019 and December 2021 were enrolled.The patients were divided into four groups:FFR+/QFR+and FFR-/QFR-,FFR+/QFR-and FFR-/QFR+with FFR or QFR≤0.80 as positive and＞0.80 as negative.Using FFR as the gold standard,the diagnostic value of QFR was analyzed,and differences in clinical features and pathological characteristics among the groups were compared.Results A total of 236 patients were included.The mean age was(64.48±9.63)years,and 67.8％were male.All patients had 30％-70％coronary stenosis.The consistency rate of QFR and FFR was 78.0％(n=184),and the Person correlation coefficient was 0.557(P＜0.001).Among FFR+patients,the minimum lumen diameter was larger[(1.56±0.34)mm vs.(1.39±0.31)mm,P=0.019],lesion length was shorter[(21.37±11.73)mm vs.(36.86±18.09)mm,P＜0.001],and coronary angiography-based index of microcirculartory resistance(AMR)was higher[(277.50±28.87)mmHg·s/m vs.(178.02±49.13)mmHg·s/m,P＜0.001]in the disconcordance group.Multivariate regression analysis suggested that AMR[OR 0.93,95％CI 0.88-0.99,P=0.030]and lesion length[OR 1.27,95％CI 1.01-1.60,P=0.045]were independent predictors of disconcordance.In the FFR-group,the lesion length was longer[(33.08±16.05)mm vs.(21.40±13.36)mm,P=0.020],and AMR[(169.66±24.01)mmHg·s/m vs.(265.95±44.78)mmHg·s/m,P＜0.001]and low-density lipoprotein-C[1.57(1.10,1.97)mmol/L vs.2.15(1.79,2.74)mmol/L,P=0.031]were lower in the disconcordance group.No statistically significant variables were identified by multivariate regression.Conclusions QFR had high diagnostic value compared with FFR.In the FFR+group,AMR and lesion length may have affected the diagnostic consistency of QFR and FFR.The study provided more evidence for the clinical application of QFR.

To understand the distribution of ticks in the Wuwei Region,enrich tick species data,and provide a basis for the prevention of tick-borne diseases,tick were collected using flagging and tick-picking methods during the highest activity period from April to September in 2021 and 2022 in the mountainous areas of Wuwei City.The ticks were identified based on morpho-logical and molecular biological characteristics,and characteristic sequences were obtained.A systematic evolutionary tree was constructed using the neighbor-joining method in MEGA 11.0 software.In total,7 342 ticks collected in Wuwei,which be-longed to 5 species from 4 genera with in the Ixodidae family,which included Dermacentor nuttalli,Hyalomma asiaticum,Ixodes canisuga,Haemaphysalis longicornis and Haema-physalis danieli.Ticks of the same species clustered together into the same branch of an evolutionary tree.In the Wuwei Re-gion,five common tick species are found across various habi-tats,with each habitat featuring different distributions of tick species and populations.The Dermacentor nuttalli is the dom-inant tick species in this area.

To understand the pathogenicity,virulence genes,drug resistance genes,and drug resistance of Staphylococcus aureus isolated from yaks in some areas of Lhasa and Nagqu City,55 yak nasal swab samples were analyzed for S.aureus in this study.The cocci were isolated and identified,and the carriage of virulence genes and drug resistance genes,as well as the pathogenicity and drug sensitivity of the isolated S.aureus strains,were detected with PCR,artificially infected mice,and the K-B drug susceptibility disk method.Seven strains of S.aureus were isolated from the 55 yak nasal swab samples,with an iso-lation rate of 12.73％.The isolated strains were all pathogenic to mice,with a fatality rate exceeding 60％.These seven strains of S.aureus carried three drug resistance genes(tetM,tet,and mecA)and six virulence genes(seb,sec,clfA,hla,hlb,and nuc).The detection rate of the three drug resistance genes was 100％,whereas the detection rate of the six virulence genes in the isolates ranged from 83.33％to 100％.The resistance rates of the isolated strains to penicillin,ampicillin,and cotrimox-azole reached 85.71％-100％,whereas the resistance rates to tetracycline and ceftazidime were both 28.57％.Thus,yaks in Lhasa and Nagqu cities were found to be infected by S.aureus strains carrying various drug-resistance genes and virulence genes.These strains were highly pathogenic and showed sensi-tivity to most antibacterial drugs.These findings may serve as a reference for treating S.aureus infection in yaks in the cities of Lhasa and Nagqu.

Investigating the species/biovars,distribution patterns,and genetic correlations of Brucella from sheep in north-west China is critical to reveal the population and epidemiological characteristics of the Brucella melitensis.In this study,con-ventional identification and AMOS-PCR were used to determine the species/biovars of Brucella isolated from 13 regions in northwest China.MLST and MLVA-16 genotyping methods were used to analyze the genetic characteristics of the strains.Con-ventional identification and AMOS-PCR detection revealed that 59 Brucella melitensis were isolated in this study,in-cluding 22 strains from Inner Mongolia,17 strains from Xin-jiang,13 strains from Gansu,and 7 strains from Qinghai,of which 58 strains were B.melitensis biovar 3,and one strain was B.melitensis biovar 1.MLST analysis indicated that 90％(53/59)of B.melitensis were of ST8 sequence type,the dominant epidemic population.The MLVA-11 survey demonstrated that 59 B.melitensis strains clustered into six MLVA-11 genotypes,and 87％of the strains were of MLVA-11 genotype 116.Therefore,the predominant strains in the northwest region were from the Eastern Mediterranean lineage.MLVA-16 divided 59 strains of B.melitensis into 40 gen-otypes,eight of which were shared genotypes.Each genotype was composed of two to seven strains from the same region,thereby indicating that the cases of each shared genotype were outbreaks from a common source of infection.All shared MLVA-16 genotypes comprised strains from the same province,thus indicating apparent regional clustering characteristics of strains in each province.In a genetic comparison between populations and isolated strains from the spleens of sheep,multiple identical MLVA-16 genotypes were found to be composed of strains from different hosts.These findings indicated a transmission path-way from sheep/goats to humans.B.melitensis biovar 3 was the main pathogen causing animal brucellosis in the northwest re-gion,and infected sheep were the main brucellosis infection source in the regional population.The ST8 strains were the domi-nant epidemic population,and the MLVA genotype of strains in each region showed clear regional clustering characteristics.

Objective:To investigate the effect of CD8+CD28-T cells on acute graft-versus-host disease(aGVHD)after haploidentical hematopoietic stem cell transplantation(haplo-HSCT).Methods:The relationship between absolute count of CD8+CD28-T cells and aGVHD in 60 patients with malignant hematological diseases was retrospectively analyzed after haplo-HSCT,and the differences in the incidence rate of chronic graft-versus host disease(cGVHD),infection and prognosis between different CD8+CD28-T absolute cells count groups were compared.Results:aGVHD occurred in 40 of 60 patients after haplo-HSCT,with an incidence rate of 66.67％.The median occurrence time of aGVHD was 32.5(20-100)days.At 30 days after the transplantation,the absolute count of CD8+CD28-T cells of aGVHD group was significantly lower than that of non-aGVHD group(P=0.03).Thus the absolute count of CD8+CD28-T cells at 30 days after transplantation can be used to predict the occurrence of aGVHD to some extent.At 30 days after transplantation,the incidence rate of aGVHD in the low cell count group(CD8+CD28-T cells absolute count＜0.06/μl)was significantly higher than that in the high cell count group(CD8+CD28-T cells absolute count ≥0.06/μl,P=0.011).Multivariate Cox regression analysis further confirmed that the absolute count of CD8+CD28-T cells at 30 days after transplantation was an independent risk factor for aGVHD,and the risk of aGVHD in the low cell count group was 2.222 times higher than that in the high cell count group(P=0.015).The incidence of cGVHD,fungal infection,EBV infection and CMV infection were not significantly different between the two groups with different CD8+CD28-T cells absolute count.The overall survival,non-recurrent mortality and relapse rates were not significantly different between different CD8+CD28-T cells absolute count groups.Conclusion:Patients with delayed CD8+CD28-T cells reconstitution after haplo-HSCT are more likely to develop aGVHD,and the absolute count of CD8+CD28-T cells can be used to predict the incidence of aGVHD to some extent.The absolute count of CD8+CD28-T cells after haplo-HSCT was not associated with cGVHD,fungal infection,EBV infection,and CMV infection,and was also not significantly associated with the prognosis after transplantation.

Objective:To investigate the molecular mechanism and distribution characteristics of RhD negative phenotypes in Han population of blood donors in Wuhu city.Methods:A total of 210 RhD-samples from August 2021 to August 2022 were screened by serological test and collected from Wuhu Central Blood Station for the voluntary blood donor population.Exons 1 and 10 of the RHD gene were amplificated by PCR to determine whether the samples had the RHD gene.Exons 1-10 of the RHD gene were amplificated by PCR and zygosity analysis were performed in 82 samples containing D gene,and Sanger sequencing was performed on 55 samples containing all RHD exons to determine the genotype.Results:Among 210 RhD-specimens,128 cases(60.38％)had RHD gene deletion.27 cases had partial exons of RHD,including 2 cases with RHD*DVI.3/RHD*01N.01,24 cases with RHD*01N.04/RHD*01N.01,and 1 case with RHD-CE(2-10)/RHD*01N.01.55 cases had retained all of 10 exons,including 4 cases with RHD*01/RHD*01N.01,6 cases with RHD*15/RHD*01N.01,1 case with RHD*01W.72/RHD*01N.01,1 case with RHD*15/RHD*01EL.01,39 cases with RHD*01EL.01/RHD*01N.01,and the remaining 4 cases were determined to have no RHD gene deletion by zygosity analysis and sequencing showed the presence of 1227G＞A mutation loci.Conclusion:There is polymorphism in the molecular mechanism of RhD-D gene in Wuhu blood donor population,among which RHD*01EL.01 and RHD*15 are the main variants in this region.The results of this study provide a theoretical basis for RhD blood group identification and clinical blood transfusion in this region.