Advances in the application of auxiliary imaging techniques in parathyroid diseases

Hypoparathyroidism is one of the main complications after total thyroidectomy,severely affecting patients’quality of life.How to effectively protect parathyroid function after surgery and reduce the incidence of hypoparathyroidism has always been a key research area in thyroid surgery.Therefore,precise localization of parathyroid glands during surgery,effective imaging,and accurate surgical resection have become hot topics of concern for thyroid surgeons.In response to this clinical phenomenon,this study compared several different imaging methods for parathyroid surgery,including nanocarbon,indocyanine green,near-infrared imaging techniques,and technetium-99m methoxyisobutylisonitrile combined with gamma probe imaging technology.The advantages and disadvantages of each method were analyzed,providing scientific recommendations for future parathyroid imaging.In recent years,some related basic and clinical research has also been conducted in thyroid surgery.This article reviewed relevant literature and provided an overview of the practical application progress of various imaging techniques in parathyroid surgery.

An Insight of the First Community Infected COVID-19 Patient in Beijing by Imported Case: Role of Deep Learning-Assisted CT Diagnosis

In the era of coronavirus disease 2019(COVID-19)pandemic,imported COVID-19 cases pose great challenges to many countries.Chest CT examination is considered to be complementary to nucleic acid test for COVID-19 detection and diagnosis.Wie report the first community infected COVID-19 patient by an imported case in Beijing,which manifested as nodular lesions on chest CT imaging at the early stage.Deep Learning(DL)-based diagnostic systems quantitatively monitored the progress of pulmonary lesions in 6 days and timely made alert for suspected pneumonia,so that prompt medical isolation was taken.The patient was confirmed as COVID-19 case after nucleic acid test,for which the community transmission was prevented timely.The roles of DL-assisted diagnosis in helping radiologists screening suspected COVID cases were discussed.

Allicin as add-on therapy for Helicobacter pylori infection: A systematic review and meta-analysis

BACKGROUND Allicin(2-propene-1-sulfinothioic acid S-2-propenyl ester,diallyl thiosulfinate)extracted from garlic,has proven activity against Helicobacter pylori(H.Pylori)infection.In recent years,clinical trials have explored its utility as an add-on therapy with variable outcomes reported.AIM To perform a systemic review of allicin as an add-on treatment for H.Pylori infection and assess its efficacy in randomized controlled trials(RCTs).METHODS Electronic databases including MEDLINE,EMBASE,the Web of Science,the Cochrane Database,the China National Knowledge Infrastructure Database,Chinese VIP Information Databases,Chinese Medical Databases,and the Wan-Fang Database were searched for keywords including“allicin”,“Helicobacter pylori”,“randomized clinical trials”,and their synonyms.A meta-analysis was performed using the fixed-effects model for low heterogeneity and the randomeffects model for high heterogeneity with sensitivity analysis.Bias was evaluated using Egger’s tests.Trial sequential analysis(TSA)was used to evaluate information size and treatment benefits.The Grading of Recommendations Assessment,Development and Evaluation(GRADE)was used to assess the level of quality,and studies were classed as“high quality”,“moderate quality”,“low quality”,and“very low quality”.RESULTS A total of eight RCTs consisting of 867 participants(435 from the allicin group and 432 from the control group)were included.Eradication rate in the allicin group(93.33%,406/435)was significantly higher than that of the control group(83.56%,361/432)[I2=0%,odds ratio(OR)=2.75,95%confidence interval(CI):1.74-4.35,P<0.001].The healing rate of ulcers following H.pylori therapy in the allicin group(86.17%,349/405)was significantly higher than that of the control group(75.87%,305/402)[I2=0%,OR=2.05,95%CI:1.39-3.03,P<0.001].The total remission rate of peptic ulcers across all allicin groups was 95.99%,which was significantly higher than that of controls[95.99%(359/374)vs 89.25%(332/372),I2=0,heterogeneity P=0.84,OR=3.13,95%CI:1.51-6.51,P=0.002].No significant differences in side effects were observed.TSA suggested that the trials were of sufficient standard to draw reliable conclusions.The quality of outcomes including eradication rates and side effects was graded as“very low”due to downgrades for“risk of bias”and“indirectness”.Other outcomes such as ulcer healing rates and total ulcer remission rates were graded as"low"due to downgrades for“risk of bias”.CONCLUSION Allicin as an add-on therapy improves H.pylori eradication,healing of ulcers,and remission of symptoms.These results are suggested to be treated with caution due to limited quality.

Hypoxia in acute cardiac injury of coronavirus disease 2019:lesson learned from pathological studies

Coronavirus disease 2019(COVID-19)is an infectious respiratory disease caused by the severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),which has infected 972,303 people and caused 50,322 deaths all over the world according to the latest WHO report.[1]As a highly contagious disease,COVID-19 has killed more people than severe acute respiratory syndrome(SARS)and middle east respiratory syndrome(MERS)combined,despite an relatively low case-fatality rate.[2,3]Although it mainly attacks respiratory system,other systems including cardiovascular system are also influenced by COVID-19.Acute cardiac injury(ACI)is also one of the noteworthy issues which researchers have noticed in several studies.[4–7] .

The Predictive Value of On-treatment Virological Response for Sustained Virological Response in Patients with Chronic Hepatitis C Receiving a Personalized Treatment Program

To investigate the effects of individualised treatment with peginterferon alpha-2a(40 kD)plus ribavirin in Chinese patients with CHC.Methods Total of 297 consecutive Chinese patients were enrolled,including 250 nave cases and 47 cases who were previously treated.Treatment duration was determined according to viral genotypes,prior treatment history and viral responses at week 4,12 and 24.Results Totally,235 patients(79.1%)completed treatment and 186(87.3%)achieved SVR.And 219 out of 289(75.8%)patients achieved HCV RNA negative at week 4(RVR)and 259 of 276(93.8%)at week 12.Among the 164 patients with RVR who completed follow-up,158(96.3%)achieved SVR.Patients with RVR had lower baseline viral loads than patients without RVR(P=0.034).The positive predictive value(PPV)of RVR for SVR was 90.7%(OR 2.10 vs.non-RVR,95%CI:0.50-8.7).Similar outcomes were observed among patients with HCV undetectable at week 12.Conclusions Viral suppression by week 4 is associated with a high rate of treatment success in treatment nave and experienced patients receiving individualized CHC therapy.

Paraneoplastic Syndromes of Hypercalcemia and Leukocytosis Associated with Colonic Metastases from Squamous Cell Carcinoma of the Lung: a Case Report

Lung cancer is the most common cancer-related death in both men and women in the world. Approximately 25% of all cancer deaths are attributable to lung carcinoma. Moreover, about one-half of patients with lung cancer have metastases at the time of initial diagnosis, most frequently of lymph nodes, adrenals, liver, bone and brain.

Application of Oral Fluid in Measles IgG Antibody Detection for Medical Staff

Measles is an acute,highly contagious,and severe respiratory disease caused by the measles virus.Infected patients can develop fever,maculopapular rashes,pneumonia,encephalitis,and other complications,including death;.A measles epidemic has persisted in China for years.Crosscontamination can easily occur in hospitals,and medical staff is at high risk for cross-infection.

Anatomy and clinical application of suprascapular nerve to accessory nerve transfer

BACKGROUND Loss of motor function in the trapezius muscle is one complication of radical neck dissection after cutting the accessory nerve(AN) during surgery.Nerve repair is an effective method to restore trapezius muscle function,and includes neurolysis,direct suture,and nerve grafting.The suprascapular nerve(SCN) and AN are next to each other in position.The function of the AN and SCN in shoulder elevation and abduction movement is synergistic.SCN might be considered by surgeons for AN reanimation.AIM To obtain anatomical and clinical data for partial suprascapular nerve-to-AN transfer.METHODS Ten sides of cadavers perfused with formalin were obtained from the Department of Human Anatomy,Histology and Embryology,Peking University Health Science Center.The SCN(n = 10) and AN(n = 10) were carefully dissected in the posterior triangle of the neck,and the trapezius muscle was dissected to fully display the accessory nerve.The length of the SCN from the origin of the brachial plexus(a point) to the scapular notch(b point) and the distance of the SCN from the origin point(a point) to the point(c point) where the AN entered the border of the trapezius muscle were measured.The length and branches of the AN in the trapezius muscle were measured.A female patient aged 55 years underwent surgery for partial SCN to AN transfer at Department of Oral and Maxillofacial Surgery,Peking University School and Hospital of Stomatology.The patient suffered from recurrent upper gingival cancer.Radical neck dissection was performed on the right side,and the right AN was removed at the intersection between the nerve and the posterior border of the SCM muscle.One-third of the diameter of the SCN was cut off,and combined epineurial and perineurial sutures were applied between the distal end of the cut-off fascicles of the SCN and the proximal end of the AN without tension.Both subjective and objective evaluations were performed before,three months after,and nine months after surgery.For the subjective evaluation,the questionnaire included the Neck Dissection Impairment Index(NDII) and the Constant Shoulder Scale.Electromyography was used for the objective examination.Data were analyzed using t tests with SPSS 19.0 software to determine the relationship between the length of the SCN and the linear distance.A P value of < 0.05 was considered as statistically significant.RESULTS The whole length of the AN in the trapezius muscle was 16.89 cm.The average numbers of branches distributed in the descending,horizontal and ascending portions were 3.8,2.6 and 2.2,respectively.The diameter of the AN was 1.94 mm at the anterior border of the trapezius.The length of the suprascapular nerve from the origin of the brachial plexus to the scapular notch was longer than the distance of the suprascapular nerve from the origin point to the point where the accessory nerve entered the upper edge of the trapezius muscle.The amplitude of trapezius muscle electromyography indicated that both the horizontal and ascending portions of the trapezius muscle on the right side had better function than the left side nine months after surgery.The results showed that the right-sided supraspinatus and infraspinatus muscles did not lose more function than the left side.CONCLUSION Based on anatomical data and clinical application,partial suprascapular nerve-to-AN transfer could be achieved and may improve innervation of the affected trapezius muscle after radical neck dissection.

中国北京地区部分医院患者疼痛现状调查(英文)

Objective:This study aimed to survey the characteristics and treatments of cancer pain in Beijing hospitals,China.Methods:At 20:00 on December 22,2009,there conducted a questionnaire survey in 2238 patients with malignant tumors of 26 hospitals in Beijing,and the survey results were statistically analyzed.Results:The 531 cases in 2238 patients had pained and 121 cases (22.79%) had outbreak pain with one week.At 20:00 on December 22,2009,199 cases (38%) in the above-mentioned 531 pain patients suffered the moderate to severe pain (pain scores ≥ 4).The number of pain (pain scores ≥ 4) patients in the consecutive three days from December 20 to December 22 were 150.Conclusion:In the 531 cancer pain patients of the surveyed hospitals,38% of the patients were not satisfied with the pain control.Doctors believed that the main reason for pain not controlled was the non-standard treatment,but patients considered to be afraid of addiction.

Detection of SARS-CoV-2 Antibodies in Oral Fluid Using a Magnetic Particle-Based Chemiluminescence Immunoassay-Beijing Municipality,China,2021

Introduction:Oral fluids(OFs)have been broadly used as non-invasive samples for evaluating protective IgG antibodies from natural infection or vaccination,especially in pediatric populations.Methods:Paired OF and serum were collected from both individuals who received a booster dose of the inactive coronavirus disease 2019(COVID-19)vaccine as well as those who did not have a history of COVID-19 vaccination and infection(as the control group).The total human IgG antibody(HIgG)content was evaluated as a marker of OF sampling quality.An in-house adapted magnetic particle-based chemiluminescence immunoassay was used for severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)IgG antibody detection in the OF.The SARS-CoV-2 IgG antibody in the serum samples was detected using a commercial immunoassay.Results:In total,579 paired OF and serum samples were collected.An additional 172 OF samples were collected from preschool children.The results indicated that the HIgG concentration in qualified OF samples should be higher than 0.3μg/mL.Compared to the serum assay,the in-house OF immunoassay for detecting IgG antibodies against SARS-CoV-2 had 95.06%accuracy,95.03%sensitivity,and 100%specificity.Conclusions:Overall,the in-house immunoassay for detecting SARS-CoV-2 IgG antibodies in OF showed high potential for application towards serological surveillance and immunization effect assessment after large-scale,inactive COVID-19 vaccination in China.

Prognosis of traumatic spinal cord injury in children:Follow-up of 86 patients

Purpose:The long-term situation of children with spinal cord injury(SCI)was investigated,and suggestions for helping them better return to the society were provided.Methods:SCI patients less than 18 years old hospitalized in Beijing Boai Hospital from January 2011 to December 2020 were retrospectively analyzed.Information including motor function,complications,characteristic changes,self-care abilities,school attendance and social participation were collected by telephone interview and electronic questionnaire.All the answers were statistically analyzed.Results:A total of 86 cases were enrolled,77 girls and 9 boys,with a median injury age of 6 years and 2 months.The follow-up time was 3-130 months.The main cause of trauma in these children was sport injury(66.3%),the thoracic spinal cord was involved the most(91.9%),and complete SCIs accounted for the majority(76.7%).In terms of complications,children with complete SCIs were more likely to have urinary incontinence,constipation and characteristic changes(p<0.05);whereas the incomplete SCIs often have spasticity(p<0.05).As to the daily living abilities,children with incomplete lumbar SCIs were more capable to accomplish personal hygiene,transfer,and bathing independently than those with complete injuries,or cervical/thoracic SCIs,respectively(p<0.05).Moreover,children older than 9 years care more able to dress and transfer independently than the youngers(p<0.05).Wheelchair users accounted for 84.9%and more than half of them were able to propel wheelchair independently,and those who move passively in wheelchairs were mostly introverted kids(p<0.05).Almost all(93.8%)children with incomplete injuries were able to walk independently.Most(79.1%)children continued to attending school,and 41.9%participated in interest classes.Unfortunately,67.4%of the children spent less time playing with their peers than before the injury.Conclusion:SCIs impair physical structures and function of children,affect their independence in daily living,and restrict school attendance and social interaction.Comprehensive rehabilitation after injury is a systematic work.Medical staff and caregivers should not only pay attention to neurological function,but also help them improve self-care abilities.It is also important to balance rehabilitation training and school work and social participation.

Angioarchitecture and prognosis of pediatric intracranial pial arteriovenous fistula

Objective Pial arteriovenous fistulas(PAVFs)are rare and mostly observed in children.However,the overall angioarchitecture,clinical features,treatments and long-term prognosis for pediatric patients remain unclear.Methods Clinical data of consecutive 42 pediatric PAVFs were documented and analysed.According to the differences of age distribution and clinical features,they were split into a younger group(≤3 years old;20 cases)and an older group(3-14 years old;22 cases).Results Their mean age was 4.9±3.9 years,and the mean preoperative modified Rankin Scale(mRS)score was 1.64±1.57.Fourteen patients(33.3%)were asymptomatic,followed by epilepsy(21.4%),intracranial haemorrhage(16.7%),hydrocephalus(9.5%),developmental delay(7.1%),intermittent headache(7.1%)and congestive heart failure(4.8%).Annual bleeding rate and rebleeding rate before treatment reached 3.86%and 3.17%.Poor venous drainage including sinus dynamic obstruction(21 cases,50.0%)and sinus occlusion(17 cases,40.48%)were found with high frequency among these patients.Finally,33 cases were cured(78.57%),and 4 cases faced surgery-related complications(9.52%).During 24-140 months’follow-up,the mean mRS score reduced to 0.57±0.40.However,only 22 cases(52.38%)recovered to absolutely normal,and poor venous drainage was the risk factor for patients’incomplete recovery(p=0.028,Exp(B)=14.692,95%CI 1.346 to 160.392).Compared with the older group,younger group showed more chronic symptoms,more secondary pathological changes,more times treatment and worse prognosis(p=0.013,0.002,0.000 and 0.032,respectively).Conclusions Pediatric PAVF has different angioarchitectures,clinical features and prognoses in different age groups.Poor venous drainage is an important factor leading to poor prognosis,and it accounts for incomplete recovery in nearly half of patients.

连续性肾脏替代疗法对老年难治性心衰患者多器官的保护作用

目的观察连续性肾脏替代疗法（CRRT）对改善老年难治性心力衰竭（心衰）患者心功能的疗效,以及对肝、肾、肺、脑等多个脏器是否存在保护作用。方法收集我院2009-2014年老年难治性心衰患者（≥60岁）共188例,其中108例仅接受传统治疗,80例接受传统疗法联合CRRT治疗。传统联合CRRT治疗组在CRRT前（当天）及CRRT后1周分别评估患者心功能、胸部X线、脑电图,以及检验血清天门冬氨酸氨基转移酶（AST）、丙氨酸氨基转移酶（ALT）、血肌酐（SCr）。传统组在相应时间同时行同样评估。结果传统联合CRRT组NYHA心功能分级（P=0.007）、AST（P=0.004）、ALT（P=0.024）、SCr（P=0.046）水平以及脑电异常活动发生率（P=0.037）均较CRRT前下降,而射血分数（EF）值（P=0.019）较CRRT前上升;与传统组比较,其NYHA分级明显改善（P〈0.001）,EF值上升（P=0.018）,AST（P=0.004）、ALT（P=0.039）、SCr（P=0.032）水平均有所下降,且传统联合CRRT组肺炎（P〈0.001）、脑电活动好转率（P=0.034）均显著高于传统组。结论 CRRT可改善老年难治性心衰患者心功能,并可减少或改善肝、肾、肺、脑等多个器官并发症的出现或损伤程度,对多个器官具有保护作用。

Economic analysis in admitted patients with acute exacerbation of chronic obstructive pulmonary disease

Background The socio-economic burden of acute exacerbation of chronic obstructive pulmonary disease （AECOPD） in Beijing is not fully understood. The study investigated the hospitalization cost in patients with AECOPD and the associated factors. Methods A multi-center, retrospective study was conducted in the four hospitals in Beijing including two level III hospitals and two level II hospitals. Patients with AECOPD admitted to the hospitals between January and December in 2006 were enrolled. The hospitalization cost and its relationship with disease severity and treatment were analyzed. Results Totally 439 patients were enrolled with 294 men （67.0%） and a mean age 73.4 years. The mean hospital stay was 20.7 days. A total of 204 patients （46.5%） had respiratory failure, 153 （34.9%） with cor pulmonale, 123 （28.0%） with coronary artery disease, 231 （52.6%） with hypertension, 70 （15.9%） with cerebrovascular disease and 32 （7.3%） with renal failure. The percentage of drug cost to total cost was the highest （71.2%）, followed by laboratory cost （16.7%）, therapy cost （9.7%）, oxygen cost （7.3%）, radiology cost （4.5%）, examination cost （4.5%）, bed cost （4.1%）. Correlation analysis showed that cost was positively correlated with age, hospitalization days, co-morbidities such as respiratory failure and cor pulmonale, hypertension. Three hundred and twenty-one patients were further analyzed. The hospitalization cost increased in patients with non-invasive ventilation （P〈0.01）, invasive mechanical ventilation （P〈0.01）, ICU stay （P〈0.01）, antibiotics （P〈0.05）, systemic steroids （P〈0.01）, and poor prognosis （P〈0.05）. Correlation analysis showed that the hospitalization cost was negatively correlated with percentage forced expiratory volume in 1 second （FEV1%） （r=-0.149, P〈0.05）, pH （r=-0.258, P〈0.01）, and PaO2 （r=-0.131, P〈0.05）, positively correlated with PaCO2 （r=0.319, P〈0.01）, non-invasive positive pressure ventilation （r=0.375, P〈0.01） and duration （r=0.463, P〈0.01）, invasive mechanical ventilation （r=0.416, P〈0.01） and duration （r=0.511, P〈0.01）, ICU stay （r=0.390, P〈0.01） and duration （r=0.650, P〈0.01）, antibiotics （r=0.140, P〈0.05） and systemic steroids （r=0.202, P〈0.01）. Conclusions AECOPD had a great impact on healthcare resources utilization. Disease severity, use of non-invasive or invasive ventilation, ICU stay and usage of antibiotics and systemic steroids were the major determinants of hospitalization cost. Long-term regular treatment aimed at reducing the frequency of acute exacerbation will lower the social and economic burden of chronic obstructive pulmonary disease （COPD）.

Regulatory Mechanisms of the Molecular Pathways in Fibrosis Induced by MicroRNAs

Objective：MicroRNAs （miRNAs or miRs） play critical roles in the fibrotic process in different organs.We summarized the latest research progress on the roles and mechanisms of miRNAs in the regulation of the molecular signaling pathways involved in fibrosis.Data Sources：Papers published in English from January 2010 to August 2015 were selected from the PubMed and Web of Science databases using the search terms ＂microRNA＂,＂miR＂,＂transforming growth factor β＂,＂tgf β＂,＂mitogen-activated protein kinase＂,＂mapk＂,＂integrin＂,＂p38＂,＂c-Jun NH2-terminal kinase＂,＂jnk＂,＂extracellular signal-regulated kinase＂,＂erk＂,and ＂fibrosis＂.Study Selection：Articles were obtained and reviewed to analyze the regulatory effects of miRNAs on molecular signaling pathways involved in the fibrosis.Results：Recent evidence has shown that miRNAs are involved in regulating fibrosis by targeting different substrates in the molecular processes that drive fibrosis,such as immune cell sensitization,effector cell activation,and extracellular matrix remodeling.Moreover,several important molecular signaling pathways involve in fibrosis,such as the transforming growth factor-beta （TGF-β） pathway,mitogen-activated protein kinase （MAPK） pathways,and the integrin pathway are regulated by miRNAs.Third,regulation of the fibrotic pathways induced by miRNAs is found in many other tissues in addition to the heart,lung,liver,and kidney.Interestingly,the actions of many drugs on the human body are also induced by miRNAs.It is encouraging that the fibrotic process can be blocked or reversed by targeting specific miRNAs and their signaling pathways,thereby protecting the structures and functions of different organs.Conclusions：miRNAs not only regulate molecular signaling pathways in fibrosis but also serve as potential targets of novel therapeutic interventions for fibrosing diseases.

Comprehensive evaluation of medullary thyroid carcinoma before surgery

Background:Medullary thyroid carcinoma(MTC)is a rare disease,but it exhibits more aggressive behaviors.The aim of this study was to improve the diagnostic accuracy of MTC before surgery by analyzing the clinical and ultrasonic data of patients with MTC.Methods:The study included 71 patients(96 lesions)with histopathologically proven MTC between April 2011 and September 2016 in the Cancer Hospital of Chinese Academy of Medical Sciences and Peking Union Medical College.The clinical characteristics and sonographic findings were retrospectively reviewed and compared between the ultrasonic correct diagnosis group and the ultrasonic misdiagnosis group with the t test or Mann-Whitney U test for quantitative parameters and the Х^2 test or Fisher exact test for qualitative parameters.Results:Compared with the ultrasonic correct diagnosis group,the proportion of the cystic change in the ultrasonic misdiagnosed group was high(25.0%vs.4.2%),the uncircumscribed margin and irregular shape proportions were low(20.8%,58.3%vs.74.7%,87.3%),calcification was relatively rare(20.8%vs.56.3%),and rich vascularity was relatively rare(25.0%vs.78.9%).Conclusions:In the case of atypical MTC,such as cystic change,circumscribed margin,regular shape,no calcification,no rich vascularity,and normal cervical lymph nodes,MTC is easily misdiagnosed as benign by ultrasound.Therefore,ultrasound,cytology and serum calcitonin should be comprehensively evaluated for a preoperative diagnosis of MTC.

Chinese Stroke Association guidelines for clinical management of cerebrovascular disorders:executive summary and 2019 update of the management of high-risk population

Aim Cerebrovascular disease is the leading cause of death and disability in China,causing a huge burden among patients and their families.Hence,stroke prevention is critical,especially in the high-risk population.Here,we present the evidence-based guideline suitable for the Chinese population.Methods Literature search of PubMed and Cochrane library(from January 1964 to June 2019)was done.After thorough discussion among the writing group members,recommendations were listed and summarised.This guideline was reviewed and discussed by the fellow writing committees of the Chinese Stroke Association’s Stroke.Results This evidence-based guideline was written in three parts:controlling the risk factors of stroke,utilisation of antiplatelet agents and assessing the risks of first-ever stroke.All recommendations were listed along with the recommending classes and levels of evidence.Conclusions This guideline provides recommendations for primary prevention of cerebrovascular disease among high-risk population in China.Controlling related risk factors,appropriately using antiplatelet agents,assessing the risk of developing first-ever stroke should help reduce the rate of cerebrovascular disease in China.

BTLA,a New Inhibitory B7 Family Receptor with a TNFR Family Ligand

B and T lymphocyte attenuator （BTLA）, identified as an immune inhibitory receptor recently, plays widespread roles on T and B cells. Emerging evidence has generated plentiful information on the mechanisms which BTLA mediates negative regulation in immune responses and involves in a variety of physiological and pathological processes. The exploration of the biological mechanisms and regulation of BTLA will open possibilities on novel therapeutic strategies in immune-related diseases. Cellular ＆ Molecular Immunology. 2005;2（6）：427-432.

Evaluation of the efficacy and safety of hydroxychloroquine in comparison with chloroquine in moderate and severe patients with COVID-19

Dear Editor,Since December 2019,severe acute respiratory syndrome coronavirus 2(SARS-CoV-2)has been rapidly spreading worldwide.Hydroxychloroquine and chloroquine are candidates for the treatment of coronavirus disease 2019(COVID-19)owing to its antiviral effect and immunomodulation properties.