[Efficacy of anti-CD19 CAR-T cell therapy in 10 refractory recurrent B cell malignancies]

目的

探讨抗CD19 CAR-T细胞治疗难治复发B细胞肿瘤的疗效和不良反应。

方法

2015年12月至2017年7月北京大学第三医院血液科收治的10例患者，包括难治复发的急性B淋巴细胞白血病（B-ALL）6例，难治复发的B细胞非霍奇金淋巴瘤（NHL）4例，采用抗CD19 CAR-T细胞治疗后观察治疗效果及不良反应。

结果

输注后第28天进行近期疗效评估，其中6例ALL患者4例（66.7%）完全缓解（CR），1例（16.7%）部分缓解（PR）；总反应率（ORR）为83.3%。3例弥漫大B细胞淋巴瘤（DLBCL）患者1例达CR。1例套细胞淋巴瘤（MCL）患者大部分病灶消失，亦有顽固病灶呈进展状态。10例患者均发生细胞因子释放综合征（CRS），主要表现为发热；其中1例患者出现中枢神经系统症状，1例患者出现多脏器功能衰竭，经治疗不良反应均治愈。

结论

抗CD19 CAR-T细胞治疗难治复发B细胞血液系统肿瘤有效，不良反应可控。

[Prognostic significance of miRNA-223 targeting SOX11 in mantle cell lymphoma]

目的

探讨miR-223在套细胞淋巴瘤（MCL）患者中的表达及预后意义，并探讨可能的作用机制。

方法

以21例骨髓受累初治MCL患者为研究对象，以20例健康正常供者为正常对照，采用RQ-PCR法检测miR-223、SOX11 mRNA表达水平。构建过表达miR-223的MCL细胞系Granta519细胞，采用CCK8法和流式细胞术检测其增殖、周期和凋亡水平，采用Western blot法检测其SOX11蛋白表达水平，并利用双荧光素酶报告基因实验验证miR-223的靶基因。

结果

①21例MCL患者中，男15例，女6例，中位年龄58（37~72）岁，其中17例为中高危组。与正常对照组比较，MCL组患者miR-223表达水平显著下调（1 244.1±1 935.2对14.7±10.5，P<0.001），且其低表达与MCL的IPI评分高危组（P=0.001）、LDH升高（P=0.001）、ECOG评分≥2分（P=0.035）等高危临床特征相关。②以患者组miR-223中位表达水平为阈值，将患者分为高表达组（10例）和低表达组（11例），生存分析结果显示前者的总生存时间较后者延长（36个月对12个月，P=0.021）。③体外实验结果显示，与对照组比较，过表达miR-223的Granta519细胞增殖受抑（96 h时最明显，P<0.001）、处于G₂/M期的细胞明显减少（P<0.001）、细胞凋亡比例增加（P<0.001）；Granta519细胞的SOX11蛋白表达水平较对照组明显降低。④miR-223可抑制SOX11的3′非翻译区；MCL患者的miR-223与SOX11 mRNA表达水平呈明显负相关（r=−0.81，P<0.001）。

结论

miR-223在MCL患者中低表达，且与不良预后相关，机制上可能通过靶向SOX11而发挥作用。

Predictive and Diagnostic Value of Fractional Exhaled Nitric Oxide in Patients with Chronic Rhinosinusitis

Background

Fractional exhaled nitric oxide (FeNO) participates in the local defense of the upper respiratory tract. Abnormal FeNO level is directly related to the occurrence of nasal diseases. However, the clinical value of FeNO in the upper airway is limited, which greatly impedes the diagnosis and treatment of nasal diseases. Here, we assessed the level of FeNO and evaluated the diagnostic accuracy of FeNO for chronic rhinosinusitis.

Material/Methods

We enrolled 35 patients with confirmed nasal inflammation and 30 healthy subjects from December 2016 and June 2017. The FeNO level was measured using a fractional exhaled nitric oxide detector. The level of FeNO in patients with different clinicopathological factors was compared. The diagnostic potential of FeNO for chronic rhinosinusitis was evaluated by receiver operating characteristic (ROC) curve analysis.

Results

FeNO level was significantly lower in patients with nasal inflammation than in healthy subjects (P<0.05). For nasal inflammation diagnosis, FeNO had the highest area under the curve (AUC) at 0.760, with a sensitivity of 93.30% and a specificity of 68.60%. FeNO level was significantly downregulated in chronic rhinosinusitis patients relative to chronic rhinitis patients (P<0.05). FeNO had a good ability to discriminate between chronic rhinosinusitis patients and chronic rhinitis patients, with higher AUC, sensitivity, and specificity of 0.760, 93.30%, and 68.60%, respectively. However, FeNO levels were not significantly different between different histological types of chronic rhinosinusitis (P>0.05).

Conclusions

Our results show that FeNO is a useful marker for discriminating chronic rhinosinusitis, and has potential to provide valuable information in the early diagnosis of chronic rhinosinusitis.

[Risk factor analysis of secondary post-tonsillectomy hemorrhage in children]

Objective: To analyze the risk factors of secondary post-tonsillectomy hemorrhage (PTH) in children, and to provide a theoretical basis for reducing complications after tonsillectomy. Method: A retrospective analysis of 354 children underwent tonsillectomy was performed, among which 42 secondary hemorrhage cases were divided into bleeding group, and other 312 cases were divided into non-bleeding group. To analyze the risk factors of secondary PTH and to discusses the pathogenesis of the hemorrhage, statistical analysis was conducted among eight clinical data including gender, age, reason of surgery, degree of tonsil embedding, surgery approach, surgeon' s skill level, intra-operative hemorrhagic volume, and postoperative absence of upper respiratory tract infection. Result: Univariant analysis showed that there was no statistical difference of gender, reason for operation, surgeon' s skill level, intra-operative hemorrhagic volume and postoperative upper respiratory tract infection different between bleeding group and non-bleeding group, while there was significant statistical difference of age, degree of tonsillar embedding, and surgery approach. Further multivariate logistic regression analysis of the three relevant factors showed that there was a significant correlation between the degree of tonsillar embedding and the surgery approach and the hemorrhage. Conclusion: Hemorrhage after tonsillectomy is a common and potentially fatal complication, with risk factors of the degree of tonsillar embedding, and the surgery approach. .

20-Hydroxyecdysone-upregulated proteases involved in Bombyx larval fat body destruction

During insect larval-pupal metamorphosis, the obsolete larval organs and tissues undergo histolysis and programmed cell death to recycle cellular materials. It has been demonstrated that some cathepsins are essential for histolysis in larval tissues, but the process of tissue destruction is not well documented. Fat body, the homologous organ to mammalian liver and adipose tissue, goes through a distinct destruction process during larval-pupal transition. Herein, we found that most of the Bombyx proteases - including Bombyx cathepsin B (BmCatB) (BmCatLL-2), Bombyx cathepsin D (BmCatD), Bombyx cathepsin L like-1 (BmCatLL-1) and -2(BmCatLL-2), Bombyx fibroinase (BmBcp), Bombyx matrix metalloprotease (BmMmp), Bombyx A disintegrin and metalloproteinase with thrombospondin motifs 1 (BmAdamTS-1), Bombyx A disintegrin and metalloproteinase with thrombospondin motifs like (BmAdamTS L) and Bombyx cysteine protease inhibitor (Bmbcpi)- were expressed highly in fat body during feeding and metamorphosis, with a peak occurring during the nonfeeding moulting or prepupal stage, as well as being responsive to 20-hydroxyecdysone (20E). The aforementioned protease genes expression was upregulated by injection of 20E into the feeding larvae, while blocking 20E signalling transduction led to downregulation. Western blotting and immunofluorescent staining of BmCatB and BmBcp confirmed the coincident variation of their messenger RNA (mRNA) and protein level during the development and after the treatments. Moreover, BmCatB, BmBcp, BmMmp and BmAdamTS-1 RNA interference all led to blockage of larval fat body destruction. Taken together, we conclude that 20E regulates larval fat body destruction by upregulating related protease gene expression and protein levels during larval-pupal transition.

[Relationship between endometrial thickness and pregnancy outcomes based on frozen-thawed embryo transfer cycles]

Objective: To explore the relationship between endometrial thickness and clinical pregnancy outcomes in frozen-thawed embryo transfer cycles. Methods: A prospective study was performed for 1 475 frozen-thawed embryo transfer cycles at Peking University People's Hospital from January 2014 to December 2015. The patients were divided into different groups according to endometrial thickness of ovulation day in natural menstrual cycles or endometrial transformation day in hormone replacement cycles;patients with thin endometrium were enndometrial thickness ≤6 mm. Then the clinical pregnancy outcomes including clinical pregnancy rate, embryo implantation rate, abortion rate, multiple birth rate and live birth rate were analyzed. Results: In all, 1 475 frozen-thawed embryo transfer cycles were analyzed. The mean age of patients was (32.5±3.9) years old and mean endometrial thickness was (9.2±1.9) mm, and mean number of embryos was 2.03±0.37. The study included 518 (35.1%) natural menstrual cycles and 957 (64.9%) hormone replacement cycles. The number of embryo-transfer cycles and blastocyst-transfer cycles were respectively 700 (47.5%) and 775 (52.5%) . The overall clinical pregnancy rate, embryo implantation rate, abortion rate, multiple birth rate and live birth rate were 54.4%, 35.7%, 23.3%, 24.1%, 43.9%, respectively. The ectopic pregnancy rate in the study was 0.6%. In patients with thin endometrium,there were significant differences in 2 pronucleus count (P=0.016) and available embryo count (P=0.024) between cycles that resulted in pregnancy and those that did not;besides, the use of sildenafil and growth hormone did not improve pregnancy outcomes in patients with thin endometrium (P=0.183, P=0.400) . The clinical pregnancy rate, embryo implantation rate and live birth rate of embryo-transfer and blastocyst-transfer were similar in patients with thin endometrium (all P>0.05) . Conclusions: Patients with thin endometrium have poor pregnancy outcomes. The clinical pregnancy rate, embryo implantation rate and live birth rate of embryo-transfer and blastocyst-transfer are similar in patients with thin endometrium. Compared thin endometrium and non-thin endometrium patients, the clinical pregnancy rate and live birth rate of blastocysts have more substantial decline than those of embryos. Improving the quality of embryo could improve the pregnancy outcome of patients with thin endometrium. Sildenafil and growth hormone could not improve pregnancy outcome in patients with thin endometrium.

Effect of DACH1 on proliferation and invasion of laryngeal squamous cell carcinoma

BACKGROUND

To investigate the effect of DACH1 over-expression on proliferation and invasion of laryngeal squamous cell carcinoma (LSCC).

METHODS

The 120 cases of LSCC tumors and 114 adjacent non-neoplastic tissues were collected to detect the expression of DACH1 by immunohistochemistry. The changes of DACH1 expression from each group were assessed and correlated to the clinical parameters of the patients. Plasmid-DACH1 was transfected into Hep-2 cells to up-regulate the expression of DACH1C. Real-time PCR, Western blot, CCK8 and transwell assay were used to verify the cell proliferation and invasion after plasmid-DACH1 transfection.

RESULTS

The results indicated that DACH1 was downregulated in LSCC tissues as compared to corresponding adjacent non-neoplastic tissues. Decreased expression of DACH1 was found in the tumors upraglottic tumor, lymph node metastases, T3-4 stage and advanced clinical stage. In Hep-2 cells, transfection with plasmid-DACH1 could suppress cell proliferation, invasion and induce G1 phase extension in cell cycle.

CONCLUSIONS

DACH1 may act as a tumor suppressor gene and could be a potential target for therapeutic intervention of LSCC.

[Progress in diagnosis and treatment of vocal fatigue]

Summary Vocal fatigue is a common symptom of voice disease, but we prefer to regard vocal fatigue as a separate voice disease. In this paper, the etiology, pathogenesis and clinical diagnosis and treatment of vocal fatigue are reviewed in order to provide reference for the standardized diagnosis and treatment of this disease.

[Comparison of safety between continued warfarin therapy and bridging anticoagulation therapy in patients undergoing coronary intervention]

Objective: To compare the safety of continued warfarin therapy and bridging anticoagulation therapy during hospital stay in patients undergoing percutaneous coronary intervention (PCI). Methods: We retrospectively analyzed patients on warfarin therapy referred for PCI in Beijing Anzhen Hospital from January 2008 to December 2016. The patients were divided into continued warfarin therapy (n=195) or bridging anticoagulation therapy (n=311) groups. After Propensity Score Matching, data from matched patients (n=123 in each group) were analyzed. Bleeding complications and major adverse cardiac events including death, myocardial infarction, target vessel revascularization, and stent thrombosis were assessed. Results: There were no significant difference in the rate of death (2.4%(3/123) vs. 1.6%(2/123),P=0.54), acute myocardial infarction (4.1%(5/123) vs. 4.9%(6/123), P=0.78),re-revascularization (0.8%(1/123) vs. 1.6%(2/123),P=0.16), stent thrombosis (1.6%(2/123) vs. 1.6%(2/123),P=1.00) and stroke between the two groups. Prevalence of minor bleeding complications was significantly higher in the bridging therapy group (15.4%(19/123) vs. 9.8%(12/123),P=0.01). Rate of access-site complications (hematoma:4.1%(5/123) vs. 2.4%(3/123),P=0.20; pseudoaneurysm:2.4%(3/123) vs. 2.4%(3/123),P=1.00; arteriovenous fistula:0.8%(1/123) vs. 1.6%(2/123),P=0.09; and retroperitoneal hematoma:0(0/123) vs. 0.8%(1/123),P=0.23) were similar between the two groups. Conclusion: For patients receiving chronic warfarin therapy, the uninterrupted oral anticoagulant treatment is as safe as bridging therapy in PCI patients.

Limb-salvage treatment of malignant tumors of the limbs

The aim of this study was to explore the clinical efficacy of limb-salvage therapy for malignant bone tumors of the limbs using two surgical methods. This investigation presents a retrospective study of malignant bone tumors of the limbs in 42 patients. Participants were divided into two groups: group A of 25 patients who were treated with artificial prosthesis replacement, and group B of 17 patients treated with bone inactivation. By collection of clinical data, the survival rate, surgical complications, quality of life, pain relief and postoperative limb function following artificial prosthesis replacement and tumor inactivation were comprehensively evaluated in patients with malignant bone tumors of the limbs. Group A had significantly higher Karnofsky quality of life scores compared to group B after six months (P=0.027). The Enneking scores of limb functions in group A were significantly higher than those of group B (P=0.022). In group A the postoperative limb function score was good and excellent in 92% and in group B in 64.7%. There were significantly more postoperative complications in group B compared with group A (P=0.027), but no significant difference in the recurrence rate in the two group (P=0.976). The study results can provide reference for surgical treatment of the patients with malignant bone tumors.

Over-expression of MEOX2 promotes apoptosis through inhibiting the PI3K/Akt pathway in laryngeal cancer cells

The early-stage diagnosis and treatment for the recurrence of larynx carcinoma needs further investigation. Mesenchyme homeobox 2 (MEOX2) was speculated as a novel suppressor gene in larynx carcinoma in our study, the molecular mechanism was studied. Real-time quantitative PCR (RT-qPCR) and Western blot were used to detect mRNA and protein levels of MEOX2 in laryngeal cancer tissues and cells (Hep-2, TU212, AMC-NH-8 and TU686 cells), and also apoptosis and phosphoinositide 3-kinase (PI3K)/protein kinase (Akt) related factors in TU212 cells transfected with MEOX2. Cell counting kit-8 (CCK8) assay and Annexin-Ⅴ/PI staining assay were conducted to determine cell viability and apoptosis rates respectively.46 patients with larynx carcinoma were involved in this study. The expression of MEOX2 was lower in larynx carcinoma tissues than normal tissues, correlated with clinical stages, differentiated degrees, and survival times. The expression of MEOX2 was the lowest among those laryngeal cancer cells, and was chosen to be transfected with MEOX2 in the following study. Over-expression of MEOX2 inhibited cell viability and promoted apoptosis of TU212 cells, via increasing the expression levels of Caspase-3, and decreasing levels of C-Myc, XIAP, PI3K p110α, PI3K p110β, PI3K class III and p-Akt. In summary, the expression levels of MEOX2 were inhibited in larynx carcinoma than normal tissues, correlated with the progression of the cancer. Over-expression of MEOX2 in laryngeal cancer cells inhibited cell viability and promoted apoptosis, via regulating apoptosis and PI3K/Akt pathway related factors. It would provide evidence for MEOX2 to be used as a therapeutical gene in larynx carcinoma.

[Analysis of survival and treatment outcome of patients with primary diffuse large B cell lymphoma in reproductive system]

Objective: To analyze clinical feature and treatment outcome of patients with primary diffuse large B cell lymphoma(DLBCL) in reproductive system. Methods: A total of 26 patients with DLBCL in reproductive system were retrospectively analyzed, and the clinical features, laboratory data were included in Kaplan-Meier and prognostic analysis. Results: In our center, the incidence of primary diffuse large B cell lymphoma in reproductive system was 3.5% in all DLBCL patients, and the median age was 62.0 years. Male are more common with unilateral testicular involvement, and 38.5% patients belong to Ⅲ and Ⅳstage while 84.6% patients belong to non-germinal center B cell-like subgroup. The overall response rate(ORR) for the whole group was 88.5%. The complete response rate was 76.9%. The 3, 5-year progression free survival rate was 70.5% and 62.7% , and the 3, 5-year overall survival rate was 83.5% and 69.6%, respectively. The most common recurrent sites were contralateral testis and central nervous system. Rituximab can improve the survival of patients and combined with contralateral irradiation can furtherly improve progression free survival of patients(P=0.047). Clinical stage, B symptom, IPI, the level of LDH, and CRP, age>60 years, and initial treatment outcome were predictive of overall survival. Conclusion: Primary diffuse large B cell lymphoma in reproductive system is a rare type of extranodal DLBCL which occurs in older men with aggressive features. The most common sites of recurrence were contralateral testis and central nervous system. Surgery, rituximab , radiotherapy and prophylactic intrathecal injection can improve the survival of patients and may be the first-line treatment.

[Analysis on the clinical and retinal imaging characteristics of autosomal recessive bestrophinopathy]

Objective: To study the clinical and imaging features of autosomal recessive bestrophinopathy (ARB). Methods: Retrospective study. The clinical and imaging data of 14 participants were analyzed in using autofluorescence (AF), fluorescein angiography (FA) and spectral-domain optical coherence tomography (SD-OCT). Ten patients were screened for mutations in BEST1 gene. Results: Retinopathy of ARB were shown as bilaterally and circularly distributed yellow subretinal deposits in the mid-peripheral and posterior retina, which was observed more clearly by AF and FA. The abnormalities were observed as hyperreflection between the sub-retinal pigment epithelium space as well as the subretinal space by SD-OCT imaging. All of the patients showed serous retinal detachment, and 4 of them were found to have intraretinal schisis. Other ocular complications include choroidal neovascularization (CNV) and angle closure glaucoma (ACG) were also found in the patients. Genetic examinations showed that the mutations are compound heterozygous in five patients, homozygous in one patient and heterozygous in only one of the rest 4 patients. Conclusions: The combination of clinical and retinal imaging data may facilitate the diagnosis of ARB. Physicians should be cautious of the vision-threatening complications of the disease. (Chin J Ophthalmol, 2018, 54: 263-269).

Identification of laryngeal cancer prognostic biomarkers using an inflammatory gene-related, competitive endogenous RNA network

Competitive endogenous RNAs (ceRNAs) act as molecular sponges for microRNAs (miRNAs), and are associated with tumorigenesis in various cancers, including laryngeal cancer (LC). In this work, we constructed an LC-specific inflammatory gene-related ceRNA network (IceNet). In IceNet, ceRNAs targeting inflammation-related genes tended to be network hubs. Additionally, the betweenness centralities of these hub ceRNAs were higher than those of the inflammation-related genes themselves, indicating that the hub ceRNAs in this study played critical roles in communication between IceNet molecules. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway analyses indicated that IceNet molecules are associated with multiple cancer-related functions and signaling pathways. Using cFinder software and survival analyses, we identified a potential prognostic module within IceNet that contains 18 mRNAs and a long non-coding RNA (lncRNA), and we effectively stratified patients into high- and low-risk subgroups with different survival outcomes, independent of patient age and tumor grade. This 18-mRNA and one-lncRNA module provides a novel mechanism for potentially improving LC patient prognostic predictions. Applying the module clinically to differentiate high- and low-risk patients could inform therapeutic decision making and ultimately improve patient outcomes. In addition, these results demonstrate the potential importance of IceNet hub ceRNAs in LC development and progression.

Significant alterations of 6-keto prostaglandin F1a and NO levels in spermatic vein plexus patients with varicocele

To investigate the level variation of correlative factors between the spermatic vein plexus and peripheral blood in patients with varicocele, a total of 22 patients diagnosed with varicocele were enrolled in the study. All patients were performed a testicular artery-sparing microsurgical varicocelectomy. During the operation, a blood sample from the left spermatic vein plexus and a peripheral blood sample were collected. A radioimmunoassay was used to determine the 6-keto prostaglandin F1a (6-keto-PGF1a ). A colorimetric method was performed to determine the NO. The enzyme immunoassay method was used to determine the creatinine, urea nitrogen, adrenaline, noradrenaline, dopamine and 5-HT. The mean age of all patients was 29.3 ± 7.8 years. Compared with the level of 6-keto-PGF1a and NO in the peripheral blood, 6-keto-PGF1a and NO were significantly increased in left spermatic vein plexus (347.3 (230.8-415.1) versus 99.7 (80.4-119.9) pg/ml and 192.3 ± 178.5 versus 107.1 ± 73.6 μmol/L, p < .05). There were no differences in the level of creatinine, urea nitrogen, adrenaline, noradrenaline, dopamine and 5-HT between the peripheral blood and left spermatic vein plexus (p > .05). The 6-keto-PGF1a and NO concentrations in left spermatic vein plexus were significantly higher than that in peripheral blood patients with varicocele.

Expression of long non-coding RNA HOXA11-AS is correlated with progression of laryngeal squamous cell carcinoma

Long noncoding RNA HOXA11 antisense RNA (HOXA11-AS) is involved in tumorigenesis and development of some human cancers. However, the role of HOXA11-AS in human laryngeal squamous cell cancer (LSCC) is yet unclear. In this study, we firstly investigated the expression of HOXA11-AS in LSCC. Microarray and qRT-PCR showed that the level of HOXA11-AS was significantly higher in LSCC than that in the corresponding adjacent non-neoplastic tissues. ISH revealed that HOXA11-AS was strongly expressed in the nucleus and closely related to the T grade, neck nodal metastasis, and clinical stage. Patients with T3-4 grade, neck nodal metastasis, or advanced clinical stage presented a high HOXA11-AS expression. Kaplan-Meier analysis showed that high HOXA11-AS expression could predict a poor prognosis in LSCC patients. Furthermore, HOXA11-AS knockdown significantly inhibited the growth, migration, and invasion of LSCC cells. Taken together, the current data indicated that HOXA11-AS plays an oncogenic role in the cellular processes of LSCC and serve as a novel marker and a potential therapeutic target in LSCC patients.

A Dynamic Three-Dimensional Air Pollution Exposure Model for Hong Kong

INTRODUCTION

High-density high-rise cities have become a more prominent feature globally. Air quality is a significant public health risk in many of these cities. There is a need to better understand the extent to which vertical variation in air pollution and population mobility in such cities affect exposure and exposure-response relationships in epidemiological studies.

METHODS

We used a novel strategy to execute a staged model development that incorporated horizontal and vertical pollutant dispersion, building infiltration, and population mobility patterns in estimating traffic-related air pollution (TRAP) exposures in the Hong Kong Special Administrative Region (HK SAR).

Two street-level spatial monitoring campaigns were undertaken to facilitate the creation of a two-dimensional land-use regression (LUR) model. A network of approximately 100 passive nitric oxide-nitrogen dioxide (NO-NO2) monitors was deployed for two-week periods during the cool and warm seasons. Sampling locations were selected based on population and road network density with a range of physical and geographical characteristics represented. Eight sets of portable monitors for black carbon (BC) and particulate matter ≤2.5 μm in aerodynamic diameter (PM2.5) were rotated so as to be deployed at 80 locations for a 24-hour period. Land-use, geographical, and emissions layers were combined with the spatial monitoring campaign results to create spatiotemporal exposure models.

Vertical air pollution monitoring was carried out at six strategic locations for two weeks in the warm season and two weeks in the cool season. Continuous measurements were carried out at four different heights of a residential building and on both sides of a street canyon. The heights ranged from as close to street level as practically possible up to a maximum of 50 meters (i.e., below the 20th floor). Paired indoor monitoring was included to allow the calculation of infiltration coefficients to feed into the dynamic component of the exposure model.

The final phase of model development addressed population mobility. A population-representative travel behavior survey (n = 89,358) was used to produce the dynamic component of the model, with time-weighted exposure estimates split between home and work or school. Transport microenvironment exposures were taken from published literature. Time-activity exposure estimates were split by age, sex, and employment status.

Development of the exposure model in distinct packages allowed the application of a staged approach to an existing cohort data set. Mortality risk estimates for an elderly cohort of 66,000 Hong Kong residents were calculated using increasing exposure model complexity.

RESULTS

The street-level (2-dimensional [2D]) LUR modeling captured important spatial parameters and represented spatial patterns of air quality in Hong Kong that were consistent with the literature. Higher concentrations of gaseous pollutants were centered in Kowloon and the northern region of Hong Kong Island. PM2.5 and BC predictions exhibited a north-south/west-east gradient, with higher concentrations in the northwest due to regional transport of particulate pollutants from Mainland China. While the degree of explained variance of the models was in line with other LUR modeling efforts in Asia, R2 values ranged from 0.46 (NO2) to 0.59 (PM2.5).

Exponential decay rates (k) were calculated at each monitoring location. While it was clear that k values were higher during the warm season than the cool season, no robust patterns were identified relating to the canyon physical parameters. Therefore, a single decay rate was used for each pollutant across the whole region for derivation of the 3-dimensional (3D) exposure layer (k = 0.004 and 0.012 for PM2.5 and BC, respectively). An alternative decay profile that capped decay at 20 meters above street level was proposed and evaluated. The electrochemical sensors deployed during the canyon campaigns did not exhibit the degree of interunit precision necessary to detect vertical variations in gaseous pollutants, and these results were excluded from the study.

We found that values of the median infiltration efficiencies (Finf) for both BC and PM2.5 were especially high during the cool season (91%). Finf values were somewhat lower during the warm season (81% and 88% for PM2.5 and BC, respectively), and we found a significant negative correlation between air conditioning use and Finf. The Finf for a mechanically ventilated office building was 45% and 40% during the cool and warm seasons, respectively.

Dynamic exposure estimates were compared against home outdoor estimates. As expected, the addition of an indoor component decreased time-weighted exposure estimates, which were balanced out to some extent by the inclusion of transport microenvironments. Overall, mean time-weighted exposures for the full dynamic model were around 20% lower than home outdoor estimates.

Higher levels of exposures were found with working adults and students than for those neither in work nor study. This was due to the increased mobility of people going to work or school. The exposures to PM2.5, BC, and NO2 were, respectively, 13%, 39%, and 14% higher for people who were under age 18, compared with people who were 65 or older. Exposure estimates for the female population were approximately 4% lower.

The availability of an existing cohort data set of elderly Hong Kong residents (n = 66,820) facilitated the calculation and comparison of mortality risk estimates for the different exposure models.

Overall, results indicated that the application of exposure estimates that incorporated infiltration, vertical, and to a lesser extent, dynamic components resulted in higher hazard ratios (HRs) than the standard street-level model and increased the number of significant associations with all-natural-cause, cardiovascular, and respiratory mortality outcomes.

CONCLUSIONS

The results from the study provided the first evidence that considering air pollution exposure in a dynamic 3D landscape would benefit epidemiological studies. Higher HRs and a greater number of significant associations were found between mortality and pollutant exposures that would not have been found had standard 2D exposure models been used. Dynamic models can also identify differential exposures between population subtypes (e.g., students and working adults; those neither in work nor study).

Improved urban building design appears to be stimulating the dispersion of local TRAP in street canyons. Conversely, Finf values found in naturally ventilated buildings were high, and residences provided little protection from ambient air pollution.

We have demonstrated that the creation of effective advanced exposure models is possible in Asian cities without an undue burden on resources. We recommend that vertical exposure patterns be incorporated in future epidemiological studies in high-rise cities where the floor of residence is recorded in health record data.

Detection and genetic characterization of porcine deltacoronavirus in Tibetan pigs surrounding the Qinghai-Tibet Plateau of China

Porcine deltacoronavirus (PDCoV) is a recently discovered RNA virus that belongs to the family Coronaviridae and genus Deltacoronavirus. This virus causes enteric disease in piglets that is characterized by enteritis and diarrhoea. In our present investigation, 189 diarrhoeic samples were collected between July 2016 and May 2017 from Tibetan pigs inhabiting in three different provinces surrounding the Qinghai–Tibet Plateau of China. We then applied the molecular‐based method of reverse transcription polymerase chain reactions (RT‐PCRs) to detect the presence of PDCoV in collected samples, and RT‐PCR indicated that the prevalence of PDCoV was 3.70% (7/189) in Tibetan pigs. Four of 7 PDCoV‐positive pigs were monoinfections of PDCoV, three samples were co‐infections of PDCoV with porcine epidemic diarrhoea virus (PEDV), and 52 (27.51%) samples were positive for PEDV. Four strains with different full‐length genomes were identified (CHN/GS/2016/1, CHN/GS/2016/2, CHN/GS‐/2017/1 and CHN/QH/2017/1), and their genomes were used to analyse the characteristics of PDCoV currently prevalent in Tibetan pigs. We found a 3‐nt insertion in the spike gene in four strains in Tibetan pigs. Phylogenetic analysis of the complete genome and spike and nucleocapsid gene sequences revealed that these strains shared ancestors with the strain CHN‐AH‐2004, which was found in pigs from the Anhui province of China mainland. However, PDCoV strains from Tibetan pigs formed different branches within the same cluster, implying continuous evolution in the field. Our present findings highlight the importance of epidemiologic surveillance to limit the spread of PDCoV in livestock at high altitudes in China.

Wearable sensors: modalities, challenges, and prospects

Wearable sensors have recently seen a large increase in both research and commercialization. However, success in wearable sensors has been a mix of both progress and setbacks. Most of commercial progress has been in smart adaptation of existing mechanical, electrical and optical methods of measuring the body. This adaptation has involved innovations in how to miniaturize sensing technologies, how to make them conformal and flexible, and in the development of companion software that increases the value of the measured data. However, chemical sensing modalities have experienced greater challenges in commercial adoption, especially for non-invasive chemical sensors. There have also been significant challenges in making significant fundamental improvements to existing mechanical, electrical, and optical sensing modalities, especially in improving their specificity of detection. Many of these challenges can be understood by appreciating the body's surface (skin) as more of an information barrier than as an information source. With a deeper understanding of the fundamental challenges faced for wearable sensors and of the state-of-the-art for wearable sensor technology, the roadmap becomes clearer for creating the next generation of innovations and breakthroughs.