Primary pleural diffuse large B-cell lymphoma:one case report and the review of literatures / 肿瘤

Objective:To describe the clinical characteristics and diagnosis and treatment process of a patient with primary pleural diffuse large B-cell lymphoma(DLBCL),in order to enhance the understanding of primary pleural DLBCL in clinical practice. Methods:The clinical characteristics and diagnosis and treatment process of a patient with primary pleural DLBCL was reported,and the related literatures were reviewed. Results:The patient complained of chest tightness and shortness of breath for over a year,and chest CT showed left pleural effusion and thickening of the left pleura.Thoracoscopic examination revealed extensive adhesions in the parietal pleura of the chest cavity,diffuse congestion of the parietal pleura,and multiple cauliflower-like new organisms.The pathological biopsy of the pleura diagnosed(left pleural mass)as DLBCL.After diagnosis,R-CHOP combined with Zebutinib treatment was performed for 4 cycles,and mid-term evaluation of chest CT showed significant regression of the tumor. Conclusion:Primary pleural DLBCL is a rare disease.It is easily to be misdiagnosed due to non-specific clinical and imaging manifestations.The final diagnosis depends ultimately on pathological biopsy,and thoracoscopy is the most effective method to confirm DLBCL.

Application of 99Tc m-MIBI SPECT/CT imaging in patients with primary cervical dystonia / 中华核医学与分子影像杂志

Objective:To evaluate the value of 99Tc m-methoxyisobutylisonitrile(MIBI) SPECT/CT imaging for the identification of dystonic muscles in patients with primary cervical dystonia (PCD). Methods:A total of 10 patients with PCD (3 males, 7 females, age (47.3±9.9) years) and 10 healthy subjects (4 males, 6 females, age (43.5±9.4) years; control group) between August 2019 and October 2021 in China-Japan Friendship Hospital were enrolled prospectively. All subjects underwent 99Tc m-MIBI SPECT/CT scan. The SUV max of 8 bilateral representative muscles, including rectus capitis posterior major, obliquus capitis inferior, splenius capitis, semispinalis, sternocleidomastoid, trapezius, musculus scalenus muscle and levator scapulae were evaluated in control group. In PCD group, muscles with abnormal uptake were determined. ROI was drawn and SUV max was measured. Independent-sample t test was used to analyze the differences of SUV max between normal and abnormal muscles. The detecting rates of neck MRI and SPECT/CT for abnormal muscles were analyzed by χ2 test. Results:Normal muscles of healthy subjects showed mild symmetrical radioactivity distribution, with the SUV max of 1.10±0.19. A total of 60 muscles with abnormal uptake in 10 patients were found, including 7 rectus capitis posterior major, 10 obliquus capitis inferior, 8 splenius capitis, 8 semispinalis, 10 sternocleidomastoid, 5 trapezius, 3 musculus scalenus muscle and 9 levator scapulae. The SUV max of muscles with abnormal uptake was 1.81±0.43, which was higher than that of normal muscles ( t=17.05, P<0.001). Only 30 pieces abnormal hypertrophy muscle were found by neck MRI, and the detecting rate was much lower than that of SPECT/CT (18.75%(30/160) vs 37.50%(60/160); χ2=28.03, P<0.001). Conclusion:99Tc m-MIBI SPECT/CT may be a useful method for identifying dystonic muscles and a guide to precision therapy in patients with PCD.

Interaction between ACOT7 and LncRNA NMRAL2P via Methylation Regulates Gastric Cancer Progression

Purpose@#Gastric cancer (GC) has a very poor prognosis when diagnosed at a late stage. Acyl-CoA thioesterase 7 (ACOT7) is a major isoform of the acyl coenzyme family that catalyzes the hydrolysis of fatty acyl-CoAs into unesterified free fatty acid and coenzyme A. The purpose of this study was to investigate the expression levels of ACOT7 in GC and mechanisms related therewith. @*Materials and Methods@#Screening of systematic biology studies revealed ACOT7 as a key gene in GC, as well as involvement of the long non-coding RNA NMRAL2P in ACOT7 expression. In this study, GC tissues and adjacent tissue samples were obtained from 10 GC patients at the Department of Gastrointestinal Surgery. GES1 and SGC-7901 cells were collected and treated to silence ACOT7 and overexpress NMRAL2P. The expressions of ACOT7 and NMRAL2P were detected by real-time quantitative PCR and Western blot. Additionally, cell proliferation, apoptosis, migration, and invasion were examined. @*Results@#ACOT7 was upregulated in gastric tumor tissues and GC cell lines. ACOT7 gene silencing induced a less malignant phenotype and was closely correlated to reduced cell proliferation and migration, altered cell cycle, and increased apoptosis. Furthermore, NMRAL2P was downregulated in tumor tissues and GC cell lines. NMRAL2P overexpression induced a more malignant phenotype and significantly inhibited the expression of ACOT7. Importantly, NMRAL2P indirectly methylated ACOT7 by binding to DNMT3b, thereby suppressing ACOT7 expression. @*Conclusion@#NMRAL2P activation suppresses ACOT7 expression in GC. Thus, ACOT7 could be a promising target for the treatment of GC.

Application of lung V/Q SPECT imaging in fibrosing mediastinitis / 中华核医学与分子影像杂志

Objective@#To investigate the value of pulmonary ventilation/perfusion (V/Q) SPECT imaging in fibrosing mediastinitis (FM).@*Methods@#From January 2015 to July 2018, 14 FM patients (6 males, 8 females, average age 74 years) who underwent V/Q SPECT imaging in China-Japan Friendship Hospital were retrospectively studied. The data of V/Q SPECT imaging were analyzed and the defect extent was classified as mild (<20%), moderate (20%-50%) and severe (>50%) according to the percentage of pulmonary perfusion and ventilation defect in total lung volume (%). χ2 test was used to analyze the incidence rates of the impaired blood perfusion of each lung lobe.@*Results@#According to the results of Q SPECT imaging, all 14 patients had impaired blood perfusion in the superior lobe of left lung, and the number of patients with/without impaired blood perfusion in the inferior lobe of left lung, superior lobe of right lung, middle lobe of right lung, inferior lobe of right lung were 11/3, 14/0, 13/1, 12/2, respectively. The incidence rates of impaired blood perfusion in different lobes were not significantly different (χ2=6.198, P=0.185). The range of lung perfusion defect was mild in 1, moderate in 7 and severe in 6 patients. The incidence rates of impaired blood ventilation in different lobes were not significantly different (χ2=1.587, P=0.811). The range of lung ventilation defeat was mild in 11, moderate in 2 and severe in 1 patients. The defect extent of lung segments and subsegments in Q SPECT imaging and V SPECT imaging were 119 and 41, respectively (χ2=28.42, P<0.05). There was more defect in Q SPECT imaging, but both methods showed segmental or subsegmental distribution.@*Conclusions@#The defect of V/Q SPECT imaging in FM patients is segmental in distribution, and more is observed in Q SPECT imaging. Pulmonary V/Q SPECT imaging can evaluate the defect range and extent of pulmonary perfusion and ventilation in FM patients.

Application of lung V/Q SPECT imaging in fibrosing mediastinitis / 中华核医学与分子影像杂志

Objective To investigate the value of pulmonary ventilation/perfusion (V/Q) SPECT imaging in fibrosing mediastinitis (FM).Methods From January 2015 to July 2018,14 FM patients (6 males,8 females,average age 74 years) who underwent V/Q SPECT imaging in China-Japan Friendship Hospital were retrospectively studied.The data of V/Q SPECT imaging were analyzed and the defect extent was classified as mild (＜20％),moderate (20％-50％) and severe (＞50％) according to the percentage of pulmonary perfusion and ventilation defect in total lung volume (％).x2 test was used to analyze the incidence rates of the impaired blood perfusion of each lung lobe.Results According to the results of Q SPECT imaging,all 14 patients had impaired blood perfusion in the superior lobe of left lung,and the number of patients with/without impaired blood perfusion in the inferior lobe of left lung,superior lobe of right lung,middle lobe of right lung,inferior lobe of right lung were 11/3,14/0,13/1,12/2,respectively.The incidence rates of impaired blood perfusion in different lobes were not significantly different (x2=6.198,P=0.185).The range of lung perfusion defect was mild in 1,moderate in 7 and severe in 6 patients.The incidence rates of impaired blood ventilation in different lobes were not significantly different (x2 =1.587,P=0.811).The range of lung ventilation defeat was mild in 11,moderate in 2 and severe in 1 patients.The defect extent of lung segments and subsegments in Q SPECT imaging and V SPECT imaging were 119 and 41,respectively (x2=28.42,P＜0.05).There was more defect in Q SPECT imaging,but both methods showed segmental or subsegmental distribution.Conclusions The defect of V/Q SPECT imaging in FM patients is segmental in distribution,and more is observed in Q SPECT imaging.Pulmonary V/Q SPECT imaging can evaluate the defect range and extent of pulmonary perfusion and ventilation in FM patients.

Analysis of Converting Non-hospital Clinical Research Coordinators to ‘Hospital Staffs’ and Their Role in the Quality Management of Clinical Trials / 医药导报

According to the quality requirements of clinical trials and the work characteristics and the development trend of clinical research coordinators ( CRCs),we proposed that converting non-hospital CRCs to hospital CRCs or ‘hospital Staffs’ and arranging them to assist quality management in clinical trials are very important and significant for improving the quality of clinical trials. In present study, we also analyzed the methods about how to convert non-hospital clinical research coordinators to hospital CRC and briefly described their role in quality management.

Protease activated receptor-1 targeted 99Tcm-(HYNIC-BMS-200261) (tricine) (TPPTS) imaging on nude mice bearing human breast cancer / 中华核医学与分子影像杂志

Objective To study the reliability of 99Tcm-(hydrazinonicotinamide (HYNIC)-BMS-200261) (tricine) (trisodium triphenylphosphine-3,3',3"-trisulfonate (TPPTS)) as a radiotracer for protease activated receptor-1 (PAR-1) expression in breast cancer.Methods Fifteen nude mice bearing MDA-MB-435,MDA-MB-231 and MCF-7 human breast cancer xenografts (5 mice for each cell line) with different PAR-1 expression were used for 99Tcm-(HYNIC-BMS-200261) (tricine) (TPPTS) γ imaging,and tumor/non-tumor (T/NT) ratios were obtained with region of interest (ROI) technique.Afterwards,the biodistribution of 99Tcm-(HYNIC-BMS-200261) (tricine) (TPPTS) was analyzed in tumor-bearing nude mice,and the radioactivity in tumor (percentage activity of injection dose per gram of tissue,％ID/g) was calculated.The immunostaining was performed to examine PAR-1 expression in tumor tissue and semi-quantitative analysis was used.One-way analysis of variance and Pearson correlation analysis were used to analyze data.Results At 2 h postinjection,the T/NT ratios were 3.03±0.32,2.27±0.25 and 1.51±0.13 respectively in nude mice bearing MDA-MB-435,MDA-MB-231 and MCF-7 xenografts;the tumor uptakes of 99Tcm-(HYNIC-BMS-200261)(tricine)(TPPTS) were (1.03±0.15),(0.56±0.14) and (0.30±0.06) ％ID/g;PAR-1 expression levels were (17.22±2.71) ％,(10.78± 1.95) ％ and (2.80± 1.18) ％,respectively (F values:47.66,46.36,62.35,all P＜0.05).The T/NT ratios and tumor uptake of 99Tcm-(HYNIC-BMS-200261) (tricine) (TPPTS) at 2 h post-injection were correlated with PAR-1 expression (r values:0.934 and 0.929,both P＜0.05).Conclusions 99Tcm-(HYNIC-BMS-200261) (tricine) (TPPTS) imaging could be a noninvasive and effective method for monitoring PAR-1 expression in human breast cancer.

Research progress in epigenetic aberrant in classic Hodgkin lymphoma / 实用肿瘤学杂志

The malignant phenotype of classical Hodgkin lymphoma ( cHL) is partly maintained by epige-netic aberrant ,of which consisted mainly abnormal histone methylation and deacetylation .Progress has been made in clinical trials related to the histone deacetylases inhibitors ( HDACis) in cHL.There is a close association noted between the epigenetic aberrants and the immune escape in cHL .DNA methyltransferase ( DNMT) inhibitors, HDACis and immune checkpoint blockade have shown synergistic effects .Further study to improve the cure rate in cHL by combination strategy is of significant importance .

Proteasome Inhibitor MG132 Inhibits Cell Proliferation and Induces Cell Apoptosis in Acute T Lymphoblastic Leukemia Cell Via FOXO3a/Puma Pathway / 中山大学学报(医学科学版)

[Objective]To explore the effect and the possible mechanism of the proteasome inhibitor MG132 on acute T lympho?blastic leukemia cells.[Methods]The influence of different concentrations of MG132 in the viability and proliferation of CCRF-CEM was measured by MTS. Apoptosis rates of CCRF-CEM treated by MG132 were determined by flow cytometry. After being exposed to MG132,the protein levels of FOXO3a in cytoplasm and nucleus were analyzed by Western blotting. qRT-PCR was applied to detect the mRNA of FOXO3a and Puma in cells treated by MG132. Then CCRF-CEM was stably transfected with antisense FOXO3a using Lentivirus infection. We further investigated the effects of MG132 in FOXO3a-shRNA cells and elucidated the mechanisms of FOXO3a and Puma.[Results]MG132 inhibits the proliferation of CCRF-CEM,but has no cytotoxicity in peripheral blood mononu?clear cells(PBMC). Cellular apoptosis was induced in cells treated with MG132. At mRNA level,MG132 had no influence on FOXO3a,but increased the expression of Puma. However,MG132 promoted the expression of both FOXO3a and Puma at protein level. Interestingly,the expression of FOXO3a increased very little in cytoplasm. In FOXO3a-shRNA cells the expression of FOXO3a and Puma decreased at protein level. FOXO3a's knockdown attenuated the proliferation inhibition mediated by MG132.[Conclusion]MG132 inhibits the proliferation and promotes to apoptosis of CCRF-CEM. One of the mechanism is that MG132 inhib? its the degradation of FOXO3a,and then activates FOXO3a/Puma pathway.

Identiifcation and validation of a novel gene expression signature for diagnosing tumor tissue origin / 中国癌症杂志

Background and purpose:Cancer of unknown primary (CUP) represents approximately 5%~10%of malignant neoplasms. For CUP patients, identiifcation of tumor origin allows for more speciifc therapeutic regimens and improves outcomes.Methods:By retrieving the gene expression data from ArrayExpress and Gene Expression Omnibus data repositories, we established a comprehensive gene expression database of 5 800 tumor samples encom-passing 22 main tumor types. The support vector machine-recursive feature elimination algorithm was used for feature selection and classiifcation modelling. We further optimized the RNA isolation and real-time quantitative polymerase chain reaction (RTQ-PCR) methods for candidate gene expression proifling and applied the RTQ-PCR assays to a set of formalin-fixed, paraffin-embedded tumor samples.Results:Based on the pan-cancer transcriptome database, we identiifed a list of 96-tumor speciifc genes, including common tumor markers, such as cadherin 1 (CDH1), kallikrein-re-lated peptidase 3 (KLK3), and epidermal growth factor receptor (EGFR). Furthermore, we successfully translated the microarray-based gene expression signature to the RTQ-PCR assays, which allowed an overall success rate of 88.4% (95%CI: 83.2%-92.4%) in classifying 22 different tumor types of 206 formalin-fixed, paraffin-embedded samples. Conclusion:The 96-gene RTQ-PCR assay represents a useful tool for accurately identifying tumor origins. The assay uses RTQ-PCR and routine formalin-ifxed, paraffn-embedded samples, making it suitable for rapid clinical adoption.

CT and 18F-FDG PET/CT features of pulmonary sclerosing hemangioma / 中华核医学与分子影像杂志

Objective To evaluate characteristics of CT and 18F-FDG PET/CT in pulmonary sclerosing hemangioma (PSH).Methods A retrospective study involving 12 patients (2 males,10 females;24-80 years old) confirmed as PSH by pathology from May 2012 to July 2014 was investigated.All patients underwent chest CT scan,including enhanced CT;and 5 cases underwent whole-body 18F-FDG PET/CT.All imaging data were collected and analyzed to find out a more effective diagnostic method.Results In 12 PSH patients,9 had single lesion,of which 4 involved left lung and 5 right lung.The rest 3 patients including 1 with two nodules located in the right lower lobe,and 2 with multiple nodules scattered in several lobes.Plain CT showed all lesions had uniformly isodensity,4 with calcification,3 with air meniscus sign.Contrast-enhanced CT examinations showed that the majority lesions were prominent enhancement and few moderate enhancement,all lesions showed vessel marginating sign and 6 with cystic and necrosis area.18F-FDG PET/CT examinations showed that the lesions displayed patchy pattern of mild to moderate uptake with SUVmax 2.2--4.0.Conclusions The characteristic CT features of PSH,especially the contrast-enhanced CT imaging,are important for diagnosis.18F-FDG PET/CT findings are extremely helpful in differentiating PSH from malignant lesions.

Clinical observation of radiofrequency thermocoagulation of lumbar sympathetic ganglia combined with pregabalin in treatment of complex regional pain syndrome / 重庆医学

Objective To observe the efficacy and safety of radiofrequency thermocoagulation of lumbar sympathetic ganglia combined with pregabalin in the treatment of complex regional pain syndrome(CRPS).Methods 26 patients with lower limb CRPS were selected and treated by the radiofrequency thermocoagulation of lumbar sympathetic ganglia combined with oral pregabalin capsule.The visual analogue scale (VAS)and the quality of sleep(QS)were adopted to evaluate the pain change before treatment and on 1,7,14,28,56 d after treatment.The temperature change of lower limb skin and the occurrence situation of adverse reactions were recorded.Results Compared with before treatment,the scores of VAS and QS at different time points after treatment were decreased significantly (P <0.05),the skin temperature of affected lower limb after treatment was increased significantly (P <0.05).The total effective rates on 28,56 d after treatment were 88.46% and 96.15% respectively.The adverse reactions were mainly dizziness and somnolence.No severe complications such as vascular,neural and intra-abdominal organs injury were found in the treatment process.Conclusion The radiofrequency thermocoagulation of lumbar sympathetic ganglia combined with pregabalin in the treatment of CRPS can rapidly alleviate pain,improve the patients′quality of sleep and living.

Elastic registration method to compute deformation functions for mitral valve / 生物医学工程学杂志

Mitral valve disease is one of the most popular heart valve diseases. Precise positioning and displaying of the valve characteristics is necessary for the minimally invasive mitral valve repairing procedures. This paper presents a multi-resolution elastic registration method to compute the deformation functions constructed from cubic B-splines in three dimensional ultrasound images, in which the objective functional to be optimized was generated by maximum likelihood method based on the probabilistic distribution of the ultrasound speckle noise. The algorithm was then applied to register the mitral valve voxels. Numerical results proved the effectiveness of the algorithm.

Study of the expression of peripheral blood lymphocyte P-glycoprotein in rheumatoid arthritis patients and reversing P-glycoprotein-induced drug resistance / 中华风湿病学杂志

Objective To study the expression of peripheral blood lymphocyte P-glycoprotein(P-gp)and related impact factors in rheumatoid arthritis(RA)patients,and explore whether the periodic combination of methotrexate(MTX)or leflunomide(LEF)with cyclophosphamide(CTX)could reverse P-gpinduced drug resistance.Methods This study was a cross-sectional study.Forty-two RA patients were enrolled(15 cases in the primary untreatment group,while 27 cases in the treatment group).In the treatment group,patients were divided into the improvement group(12 patients)and the refractory group(15 patients)respectively according to their disease activity scores(DAS 28).According to the medication used,42 patients were divided into 3 groups:the monotherapy group(MTX or LEF),the MTX+LEF combination treatment group and MTX or LEF+CTX treatment group.The expression of peripheral blood lymphocyte P-gp in each group was detected by flow cytometry.T test,ANOVA,LSD test,Bonferroni test,x2 test and Pearson correlation analysis were used for statistical analysis with software 13.0.Results ① Mean relative fluore scence intensity(RFI)of P-gp was 2.0±0.7,2.9±1.0,3.5±1.4,5.0±2.0 respectively in healthy control group,the primary untreatment group,the improvement group and the refractory group,the difference was significant(F=7.955,P＜0.01).in multiple comparisons,the fluorescence intensity was higher in the primary untrea-tment group as compared to the healthy group,but the difference was not statistically significant(P=0.137);however,it was significantly higher in the refractory group as compared to the improvement group(P=0.013).② There was no correlation between the expression of P-gp in RA patients and sex,age of onset,disease duration or positive rate of RF.But the expression of P-gp was significantly correlated with ESR and DAS28(r=0.447,P=0.002;r=0.398,P=0.012).③ RFI of the P-gp group was 5.1±2.2,6.0±1.2,3.4±1.1 respectively in monotherapy group,MTX+LEF group and MTX/LEF+ CTX group(P＜0.05).The expression of P-gp was significantly lower in the MTX/LEF+CTX group as compared to the monotherapy group(P＜0.05),but higher in the MTX+LEF group(P＞0.05).Conclusion The expression of peripheral blood lymphocyte P-gp in RA is correlated with disease activity.The loss of efficacy in DMARDs is due to the enhanced expression of P-gp.Combination of methotrexate or leflunomide with cyclo-phosphamide reverses P-glycoproteininduced drug resistance.

Impact of different surveillance models on the quality of injury surveillance / 中华疾病控制杂志

Objective To find out the impact of different surveillance models on the quality of injury surveillance and to provide a scientific basis for improving the quality of injury surveillance based in emergency departments and based on the basic data for evaluating the quality and advancing its method.Methods On the premise of the same surveillance,process and method,the injury reports the two trained groups(part-time and full-time)filled out within one month from July 28th to August 27th in 2007 were collected.They were processed in the computer,examined,and finally compared.Results The omitted rate of PTSIS was 31.44%,higher than that of FTSIS,especially during the latter part of night when it was easier for the two models to be omitted.There was a difference in error in the report-filling:Part-time group was often found to have omitted "telephone number","the cause of injury" and "intent",while the full-time group more readily left out "injury severity","patient disposition",and "responder".The part-time group did a better job on "the mechanism of injury" and "disposition",and the integrity of their report-filling was greater than that of the full-time group by 12.84%.Conclusions The omitted rate of PTSIS is higher than that of FTSIS,while the quality of the report from PTSIS is better than that of FTSIS.Therefore in the condition of the limited resources,part-time groups' active participation in the injury surveillance should be encouraged.The full-time groups are expected to be trained for it if resources permit.

Integrating Clinical Knowledge into Pharmacology Teaching: Investigation and Estimate / 中华医学教育探索杂志

Objective:The purpose of this study was to improve teaching quality of pharmacology by integrating different form of clinical knowledge.Methods:We tried to add the clinical documents such as some related videos and pictures,many common drugs' trade-names and analysis of typical cases into teaching of pharmacology in undergraduate course in our college.Results:Both the theory examination scores and ability of aggregate analysis of cases were higher in the experiment groups than in the controlled ones.And the students considered that the teaching mode with clinical knowledge could stir up their interest in learning pharmacology and increase teaching effect.Conclusion:The teaching mode of incorporating clinical knowledge into pharmacology would be helpful to improve teaching quality of pharmacology.

Effect of puerarin on the expression of NF-?B65 and TNF-? in kidney of diabetic rats / 解放军医学杂志

Objective To observe the effect of puerarin on the expression of NF-?B65 and TNF-? in kidney of diabetic rats. Methods SD rats were randomly assigned to 5 groups (10 each):normal control group (group A),diabetic group (group B),low-dose,middle-dose and high-dose treatment groups (group C,D and E). After diabetes model was reproduced,animals in group C,D and E were i.p. injected with puerarin in a dose of 40,80 and 160mg/(kg?d),respectively; animals in group A and B were treated with corresponding normal saline. Fasting blood glucose (FBG),urinary albumin excretory rate (UAER),serum creatinine (Scr) and blood urea nitrogen (BUN) were determined at the 8th weekend after treatment. The histological changes in renal cortex were observed with light microscope and electron microscope. The qualitative and semi-quantitative expressions of NF-?B65 and TNF-? in nephridial tissue were determined by immunohistochemical method. Results FBG,UAER,Scr and BUN were higher in group C,D and E than that in group A (P

Research advances in breast cancer resistance protein (BCRP) / 中国癌症杂志

WTBZ]Breast cancer resistance protein (BCRP) is a recently discovered half-transporter belonging to the ABC transporter superfamily as P-glycoprotein(P-gp) and multiple resistance protein (MRP). The latest research results concerned BCRP on construction features of gene, relationship to differentiation of hemopoietic stem cell and correlated transport substrates were reviewed in the article and it's clinical significance was mentioned at the same time.

Insights into the practical effectiveness of RT-PCR testing for SARS-CoV-2 from serologic data, a cohort study

BackgroundVirologic detection of SARS-CoV-2 through Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) has limitations for surveillance. Serologic tests can be an important complementary approach. ObjectiveAssess the practical performance of RT-PCR based surveillance protocols, and the extent of undetected SARS-CoV-2 transmission in Shenzhen, China. DesignCohort study nested in a public health response. SettingShenzhen, China; January-May 2020. Participants880 PCR-negative close-contacts of confirmed COVID-19 cases and 400 residents without known exposure (main analysis). Fifty-seven PCR-positive case contacts (timing analysis). MeasurementsVirological testing by RT-PCR. Measurement of anti-SARS-CoV-2 antibodies in PCR-negative contacts 2-15 weeks after initial testing using total Ab ELISA. Rates of undetected infection, performance of RT-PCR over the course of infection, and characteristics of seropositive but PCR-negative individuals were assessed. ResultsThe adjusted seropositivity rate for total Ab among 880 PCR-negative close-contacts was 4.1% (95%CI, 2.9% to 5.7%), significantly higher than among residents without known exposure to cases (0.0%, 95%CI, 0.0% to 1.0%). PCR-positive cases were 8.0 times (RR; 95% CI, 5.3 to 12.7) more likely to report symptoms than the PCR-negative individuals who were seropositive, but otherwise similar. RT-PCR missed 36% (95%CI, 28% to 44%) of infected close-contacts, and false negative rates appear to be highly dependent on stage of infection. LimitationsNo serological data were available on PCR-positive cases. Sample size was limited, and only 20% of PCR-negative contacts met inclusion criteria. ConclusionEven rigorous RT-PCR testing protocols may miss a significant proportion of infections, perhaps in part due to difficulties timing testing of asymptomatics for optimal sensitivity. Surveillance and control protocols relying on RT-PCR were, nevertheless, able to contain community spread in Shenzhen. Funding sourceBill & Melinda Gates Foundation, Special Foundation of Science and Technology Innovation Strategy of Guangdong Province of China, and Key Project of Shenzhen Science and Technology Innovation Commission, Shenzhen, China

Evolving Epidemiology and Effect of Non-pharmaceutical Interventions on the Epidemic of Coronavirus Disease 2019 in Shenzhen, China

Previous studies have demonstrated the characteristics of patients with 2019 novel coronavirus disease (COVID-19). However, the effect of non-pharmaceutical interventions on the epidemic in Shenzhen, China remains unknown. Individual data of 417 cases were extracted from the epidemiological investigations and the National Infectious Disease Information System between January 1, 2020 and February 29, 2020. On the basis of important interventions, the epidemic was divided into four periods (January 1-15, January 16-22, January 23-February 5 and after February 6). We used a susceptible-exposed-infectious-asymptomatic-recovered model to evaluate the effect of interventions. Results suggested that about 53.7% were imported from Wuhan. The median age was 47 years and 52.8% were women. Severity risk increased with age and associated with male and co-existing disorders. The attack rate peaked in the third period and drastically decreased afterwards across sex, age groups and geographic regions. Children younger than 5 years showed a higher attack rate than those aged of 6~19. The effective reproductive number decreased from 1.44 to 0.05 after the highest level emergency response since January 23. Overall, the non-pharmaceutical interventions have effectively mitigated the COVID-19 outbreak in Shenzhen, China. These findings may facilitate the introduction of public health policies in other countries and regions.