Cytoplasmic Lipid Droplets Predict Worse Prognosis in Diffuse Large B-Cell Lymphoma: Next-Generation Sequencing Deciphering Lipogenic Genes.

Burkitt lymphoma is characterized by high cell turnover and numerous cytoplasmic vacuoles that are demonstrated to be lipid droplets (LDs) decorated by adipophilin. By contrast, cytoplasmic vacuoles are variably observed in diffuse large B-cell lymphoma (DLBCL) and less well characterized. In this study, we first validated in DLBCL that cytoplasmic vacuoles are indeed LDs by Oil-red-O stain, Bodipy fluorescent stain, and electron microscopy. Second, in a cohort of DLBCL patients (n=52) we showed that LDs in effusional lymphoma cells were associated with a poorer prognosis (P=0.029, log-rank test) and higher International Prognostic Index (IPI) score (94% vs. 66%, P=0.026) than those without. Moreover, using adipophilin as a surrogate marker for LDs, we found in another cohort of biopsy specimen (n=85) that expression of adipophilin by lymphoma cells predicted a poorer prognosis (P=0.007, log-rank test) and higher IPI score (63% vs. 30%, P=0.005). In addition, whole exome sequencing of effusional DLBCL cells showed LD-positive DLBCL shared genetic features with the MCD (MYD88 and CD79B mutations) subtype and highlighted OSBPL10 and CUBN as the most frequently mutated genes involved in lipogenesis. Whole transcriptome analysis by comparing effusional DLBCL cells with versus without LDs showed upregulation of EHHADH, SLC1A1, CD96, INPP4B, and RNF183 relevant for lymphoma lipogenesis and upregulation of epithelial-mesenchymal transition and KRAS signaling pathways. Higher expression of EHHADH and CD96 were validated in LD-positive clinical samples and LD-rich cell lines than LD-poor cells along with the known lipogenic gene, FASN. Our findings highlight the roles of LDs and adipophilin expression in DLBCL, suggest that these markers may predict prognosis and show that lipogenic genes may be potential therapeutic targets.

Frequent expression of PD-L1 in BLS-type diffuse large B-cell lymphoma: implications for aggressiveness and immunotherapy.

BLS-type diffuse large B-cell lymphoma (DLBCL) denotes an uncommon, aggressive variant of DLBCL presenting initially in bone marrow, liver and spleen without lymphadenopathy or mass lesion. Patients with BLS-type DLBCL present frequently with haemophagocytic syndrome which often leads to early patient demise. Programmed death ligand 1 (PD-L1) plays a negative regulatory role on effector T cells and is an important target of immunotherapy. Assessment of PD-L1 expression in BLS-type DLBCL may carry therapeutic implications and provide mechanistic insights. Standard immunohistochemical analysis for PD-L1 was performed in seven cohorts for this study: (1) DLBCL-not otherwise specified (NOS) (n=201); (2) Epstein-Barr virus (EBV)-positive DLBCL (n=26); (3) thymic (primary mediastinal) DLBCL (n=12); (4) intravascular LBCL (n=3); (5) high-grade B-cell lymphoma, NOS (n=12); (6) BLS-type DLBCL (n=37); and (7) systemic DLBCL involving bone marrow (n=28). We found that PD-L1 was positive in 12.9% of DLBCL-NOS cases, 46.2% of EBV-positive DLBCL, 91.7% of thymic LBCL, none of intravascular LBCL, 8.3% of high-grade B-cell lymphoma-NOS, and 56.8% of BLS-type DLBCL. By comparison, only 14.3% of bone marrow cases involved by systemic DLBCL were positive for PD-L1 (p<0.001). Interestingly, BLS-type DLBCL more frequently showed activated B-cell phenotype (86.5% vs 65.2%, p=0.010), a high Ki-67 proliferative index (97.1% vs 63.3%, p<0.001), MYC overexpression (90.9% vs 56.2%, p=0.023), presence of haemophagocytic syndrome (86.5% vs 4.0%, p<0.001), and poorer overall survival (p<0.001) than DLBCL-NOS. These data suggest that the poor prognosis of BLS-type DLBCL may be explained by both extrinsic tumour microenvironment factors and intrinsic genetic factors of tumour cells, such as PD-L1-associated inactivation of anti-tumour immunity for the former, and MYC pathway activation-related aggressiveness for the latter.

Clinical implications of PNA­sequencing as a complementary test for EGFR mutation analysis in human lung cancer.

Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) are the first-line regimen for the treatment of non-small cell lung cancer (NSCLC) patients with EGFR mutations. However, false-negative results are occasionally observed, even with FDA-approved molecular tests. Such examples in have been reported in our pilot study showing a slightly upward-shifted amplification curve using commercial reverse transcription-quantitative (RT-q)PCR. Verification using peptide nucleic acid (PNA) clamping-sequencing, which has a sensitivity of ~0.1%, may allow better prediction of which patients will benefit from EGFR-TKI therapy. To confirm this hypothesis, samples were prospectively collected from 1,783 lung cancer cases diagnosed in National Cheng Kung University Hospital between 2012-2018. An independent lung cancer cohort of 1,944 cases was also recruited from other hospitals. The clinical significance of mutant-enriched PCR with PNA-sequencing was analyzed and patient outcomes were followed. A total of 17 of 34 cases (50%) were found to harbor EGFR mutations by PNA-sequencing. A total of 22 cases were discovered in the independent lung cancer cohort, and 14 of these (63.6%) cases had EGFR mutations. TKIs were administered to 14 of the 17 mutation-positive patients, and a partial response was observed in 4 cases and stable disease in 10 cases. Patients with EGFR mutations receiving a TKI regimen had a longer overall survival (OS) (median: 40.0 vs. 10.0 months) compared with those without treatment. The difference in OS was not significant. Based on the results of the present study, combining RT-qPCR with PNA-sequencing may be a practical supplementary technology in a clinical molecular laboratory for a subset of lung cancer patients in selection of EGFR TKI therapy.

Cross-Scale Fusion Transformer for Histopathological Image Classification.

Histopathological images provide the medical evidences to help the disease diagnosis. However, pathologists are not always available or are overloaded by work. Moreover, the variations of pathological images with respect to different organs, cell sizes and magnification factors lead to the difficulty of developing a general method to solve the histopathological image classification problems. To address these issues, we propose a novel cross-scale fusion (CSF) transformer which consists of the multiple field-of-view patch embedding module, the transformer encoders and the cross-fusion modules. Based on the proposed modules, the CSF transformer can effectively integrate patch embeddings of different field-of-views to learn cross-scale contextual correlations, which represent tissues and cells of different sizes and magnification factors, with less memory usage and computation compared with the state-of-the-art transformers. To verify the generalization ability of the CSF transformer, experiments are performed on four public datasets of different organs and magnification factors. The CSF transformer outperforms the state-of-the-art task specific methods, convolutional neural network-based methods and transformer-based methods. The source code will be available in our GitHub https://github.com/nchucvml/CSFT.

The experience of neoadjuvant chemotherapy versus upfront surgery in resectable pancreatic cancer: a cross sectional study.

BACKGROUND: Upfront resection (UR) followed by adjuvant chemotherapy remains the standard treatment for resectable pancreatic cancer. There is increasing evidence suggesting favourable outcomes toward neoadjuvant chemotherapy (NAC) followed by surgery. METHODS: All clinical staging with resectable pancreatic cancer patients treated at a tertiary medical centre from 2013 to 2020 were identified. The baseline characteristics, treatment course, surgery outcome and survival results of UR or NAC were compared. RESULTS: Finally, in 159 resectable patients, 46 patients (29%) underwent NAC and 113 patients (71%) received UR. In NAC, 11 patients (24%) did not receive resection, 4 (36.4%) for comorbidity, 2 (18.2%) for patient refusal and 2 (18.2%) for disease progression. In UR, 13 patients (12%) were unresectable intraoperatively; 6 (46.2%) for locally advanced and 5 (38.5%) for distant metastasis. Overall, 97% of patients in NAC and 58% of patients in UR completed adjuvant chemotherapy. As of data cut-off, 24 patients (69%) in NAC and 42 patients (29%) in UR were still tumour free. The median recurrence-free survival in NAC, UR with adjuvant chemotherapy and without adjuvant chemotherapy were 31.3 months (95% CI, 14.4-not estimable), 10.6 months (95% CI, 9.0-14.3) and 8.5 months (95% CI, 5.8-11.8), P =0.036; and the median overall survival in each group were not reached (95% CI, 29.7-not estimable), 25.9 months (95% CI, 21.1-40.5) and 21.7 months (12.0-32.8), P =0.0053. Based on initial clinical staging, the median overall survival of NAC was not significantly different from UR with a tumour less than or equal to 2 cm, P =0.29. NAC patients had a higher R0 resection rate (83% versus 53%), lower recurrence rate (31% versus 71%) and harvested median number lymph node (23 versus 15). CONCLUSION: This study demonstrates that NAC is superior to UR in resectable pancreatic cancer with better survival.

Variable radiographic and histologic presentations of amiodarone-related interstitial lung disease and the importance of avoiding re-exposure.

Amiodarone is a commonly used antiarrhythmic agent but exhibits potential pulmonary toxicity. In this case series, we describe the clinical, radiographic, and histologic manifestations of three patients who developed interstitial lung disease (ILD) following amiodarone treatment for variable lengths of time with different dosages. The presentations on computed tomographic images and in pulmonary pathology differed among the three patients. All three had immediate discontinuation of amiodarone and received treatment with systemic corticosteroids. One patient eventually died from ventilator-associated pneumonia after an initial improvement. The other two patients recovered well but later experienced ILD recurrence following brief re-exposure to amiodarone. Through this case series, we aim to demonstrate the variable features of amiodarone-related ILD, and highlight the importance of timely amiodarone cessation and avoiding re-exposure to prevent the progression and recurrence of ILD.

Impact of computed tomographic patterns and extent on clinical management and outcomes of patients with organising pneumonia.

Background: Organising pneumonia (OP) has variable clinical and radiographic presentations and unstandardised treatments. Most patients with OP have favourable outcomes, but some develop respiratory insufficiency, experience recurrence or die. In this study we investigated the impact of computed tomographic (CT) patterns and extent of OP on the diagnostic and therapeutic management that patients received, and that on the therapeutic response and prognosis (particularly the risk of respiratory insufficiency and death). Methods: We retrospectively studied 156 patients with OP followed at our hospital between 2010 and 2021. The diagnosis was confirmed histologically and verified by multidisciplinary specialists. We performed Firth's logistic regression to determine the relationship between CT features and aetiologies, management and outcomes including the risk of severe disease (defined as the need for supplemental oxygen or mechanical ventilation). We conducted Kaplan-Meier analyses to assess survival differences. Results: Patients exhibiting multilobe involvement or mixed patterns, or both, were more likely to have secondary OP and receive immunosuppressants. Higher proportions of these patients experienced recurrence. Compared to patients with single-lobe involvement and single-pattern, they also had an enhanced risk of severe disease (the adjusted odds ratio for patients who simultaneously had multilobe involvement and mixed patterns was 27.64; 95% confidence interval 8.25-127.44). Besides, these patients had decreased survival probabilities. Conclusion: Different CT features of OP impact patients' management and prognosis. When treating patients with OP exhibiting multilobe involvement or mixed patterns, or both, it is important to identify the possible causative aetiology and follow closely for adverse outcomes.

Investigation into the content of red material in EUS-guided pancreatic cancer biopsies.

BACKGROUND AND AIMS: The red material occupying the larger portion of the acquired sample in EUS fine-needle biopsy (FNB) is seldom investigated. We aimed to evaluate the composition of the red material. METHODS: Patients with a solid pancreatic mass who received EUS FNB from September 2020 to June 2021 were enrolled. The white or yellowish content with apparent bulk (white material) and the rest of pasta-like red content (red material) were separated immediately after puncture. Needle passes proceeded until 2 specimens with >4 mm of white material were obtained. An extra needle pass was conducted for DNA collection. The DNA amount, Kirsten rat sarcoma virus (K-ras) mutation type, and mutation allele frequency were compared between the white and red material. RESULTS: Forty patients were enrolled with 68 paired white and red materials. The diagnostic accuracy was slightly higher in the white material (92.5% vs 82.5%, P = .219). On the histology slides, the area of the tumor gland was comparable in both materials, but the total tissue area was larger in the red material (9.74 mm2 and 10.74 mm2 larger according to generalized linear model and generalized estimating equation, respectively; both, P < .001). The amount of DNA was significantly higher in the red material (2.99 [interquartile range, 1.59-7.29] µg vs .70 [interquartile range, .27-1.24] µg; P < .001). Common pancreatic adenocarcinoma K-ras mutation was identified at a rate of 85% for the white material and 95% for the red material. Regardless of whether red or white material was used, there was a high concordance of K-ras mutation types (34 of 40 [85%]) and a high correlation of mutation allele frequency (ρ = .66, P < .001). CONCLUSIONS: In EUS FNB, the red material contains a higher amount of tumor DNA and can be an alternative source for tumor DNA analysis.

Evolution of the Correa's cascade steps: A long-term endoscopic surveillance among non-ulcer dyspepsia and gastric ulcer after H. pylori eradication.

BACKGROUND: This study is aimed toward investigating the evolution of each Correa's step after Helicobacter pylori eradication in a long-term follow-up and exploring the factors correlated with a high-risk of gastric cancer. METHODS: A total of 1824 H. pylori-infected subjects were enrolled to receive screening endoscopy. Among them, 491 received surveillance endoscopy. The patients were divided into Correa's steps I to VI, from normal to gastric cancer. A group-based trajectory model was used to classify patients as persistent high-risk status or not. RESULTS: The prevalence rates of positive corpus-predominant gastritis index (CGI) were 20%-40% in all age groups and Correa's steps IV-V increased >35% after 50 years based on screening endoscopy. Successful eradication of H. pylori regressed CGI after the 1st year-and-thereafter (P < 0.05) and decreased Correa's step progression (Relative risk 0.66 [95% CI 0.49-0.89], P = 0.01); however, it did not regress OLGA and OLGIM. Not only in steps IV-V, but also in step III, the patients had a risk of developing gastric cancer (11.13-76.41 and 4.61 per 1000 person-years). Age (Hazard ratio 1.012 [1.003-1.020], P = 0.01), OLGA stages ≥ I (2.127 [1.558-2.903], P < 0.001), and OLGIM stages ≥ I (1.409 [1.119-1.774], P = 0.004) were correlated independently with a persistent high-risk status. CONCLUSION: The patients in Correa's steps III-V, but not I-II, were at risk of gastric cancer after H. pylori eradication. Age, OLGA stages ≥ I, and OLGIM stages ≥ I were independent factors correlated to a persistent high-risk of gastric cancer. The data may be useful when scheduling surveillance endoscopy for subjects in each Correa's step (NCT04527055).

Evaluation of City-Scale Disparities in PM2.5 Exposure Using Hyper-Localized Taxi-Based Mobile Monitoring.

Efforts have been directed to pollution control of fine particles (PM2.5) because exposure to PM2.5 could result in adverse health effects. However, PM2.5 exposure disparities persisted even with largely declined concentrations. Here, we applied taxi-based measurements to characterize hyper-localized PM2.5 exposures (30 m resolution) in Xi'an in December 2019 and July 2020. A big data set was derived from the taxi-based measurements (∼6 × 106 hourly PM2.5) and was used to evaluate the performance of existing regulatory measurements in urban and rural regions. Results from regulatory measurements tend to alleviate PM2.5 exposure disparities compared with taxi-based measurements. The taxi-based measurements reported higher population-weighted average (PWA) exposure in December 2019 (90 µg/m3) and July 2020 (27 µg/m3) compared to regulatory measurements (76 and 24 µg/m3 in December and July, respectively) with a wider range of relative disparities. Results indicate that the urban region would be overrepresented by regulatory measurements, where regulatory measurements reported that 60.0-84.7% of inhabitants were exposed to PM2.5 higher than PWA, while taxi-based ones reported a smaller portion (22.6-35.2%). Significant seasonal variability in PM2.5 exposure levels was found by taxi-based measurements but not regulatory measurements. The results highlight the need for providing complementary measurements (e.g., low-cost) for exposure assessment because the rural regions could be disproportionately exposed and overlooked by existing regulatory measurements.

Improved survival with induction chemotherapy and conversion surgery in locally advanced unresectable pancreatic cancer: a single institution experience.

Both efficacy and tolerability are critical issues in choosing neoadjuvant chemotherapy in patients with unresectable locally advanced pancreatic cancer (LAPC). The optimal regimen and the impact of conversion surgery on patient survival remains insufficiently reported in Asain population. Therefore, we conducted a retrospective study aiming to evaluate the resection rate after different induction chemotherapy regimen and its impact toward survival. All patients with pancreatic cancer treated in our institute from 2013 to 2020, a total of 730 patients, were reviewed and 131 patients with LAPC were identified. For cohort homogeneity, 14 patients receiving induction concurrent chemoradiotherapy initially were excluded and 117 patients receiving induction chemotherapy were included in the study. Most patients (90 of 117, 77%) received triplet induction chemotherapy, including the combination of S1, leucovorin, oxaliplatin and gemcitabine (SLOG) in 48, modified FOLFIRINOX in 21 and the combination of gemcitabine, oxaliplatin, fluorouracil and leucovorin (GOFL) in 21. The tumor response rate (19%-33%), the surgical exploration rate (38%-52%) and the mOS (15.4-23.0 months) were not significantly different among the three triplets. Both GOFL and SLOG regimen had comparable efficacy and less neutropenia as compared to mFOLFIRINOX. Conversion surgery was performed in 34 of 117 (29%) patients after induction chemotherapy. The median overall survival (mOS) in patients with and without conversion surgery were 29.1 and 14.1 months, respectively (P<0.0001). Radiological response alone was not a reliable indicator of successful conversion surgery. Patients who underwent conversion surgery had significantly better survival and thus highlighted the importance of surgical exploration in all patients who did not have progressive disease after induction chemotherapy.

Efficacy of Coxsackievirus A2 vaccine candidates correlating to humoral immunity in mice challenged with a mouse-adapted strain.

BACKGROUND: In recent years, Coxsackievirus A2 (CV-A2) has become one of the main serotypes of enterovirus species A associated with hand, foot and mouth disease (HFMD) in China. It has also caused HFMD epidemics in many countries all over the world. Currently, there are no effective, preventive vaccines against it. METHODS: A CV-A2 strain was isolated in RD cells and then adapted to grow in Vero cells. This is in compliance with guidelines for cell substrates allowed for human vaccines by the Chinese regulatory authority. Groups of newborn Kunming mice were inoculated on day 3 and day 9 using two formulations of candidate vaccines, empty particles and full particles. They were then challenged on day 14 at a lethal dose with a mouse-adapted strain. RESULTS: The mice in the control group all died within 14 days post-challenge whereas most of the mice in the candidate vaccine groups survived. It was found that the titers of neutralizing antibodies was dose-dependent in sera of immunized mice. The results also showed that the vaccine candidates stimulated a strong humoral immune response and protected the mice from disease and death. The virus loads in tissues or organs were significantly reduced and pathological changes were either weak or not observed in the immunized groups compared with those in Al(OH)3 control group. Preliminary mapping of the nucleotide and amino acid residues potentially related to cell tropism of the vaccine strain and virulence of the challenge strain was performed. CONCLUSION: The results showed that the RD cell-isolated and Vero cell-adapted CV-A2 strain is a promising vaccine candidate. This active immunization-challenge mouse model mimics the vaccination and then exposure to wildtype viruses, compared with passive immunization-challenge model, and is invaluable for efficacy evaluation in studies on multivalent vaccines containing CV-A2 against HFMD.

Characterizing spatial variations of city-wide elevated PM10 and PM2.5 concentrations using taxi-based mobile monitoring.

The spatial distribution of elevated particulate matter (PM) concentrations represents a public health concern due to its association with adverse health effects. In this study, a city-wide spatial variability of PM (PM10 and PM2.5) concentrations in Jinan, China is evaluated using a combination of measurements from 1700 fixed sites and taxi-based mobile monitoring (300 taxis recruited). The taxi fleet provides high spatial resolution and minimizes temporal sampling uncertainties that a single mobile platform cannot address. A big dataset of PM concentrations covering three land-use domains (roadway, community and open-field) and pollution episodes is derived from the taxi-based mobile monitoring (~3 × 107 pairs of PM10 and PM2.5). The ability of taxi-based mobile monitoring to characterize location-specific concentrations is assessed. We applied an "elevation ratio" to identify the elevated PM concentrations and quantified the ratios at 30-m road segments. Higher PM concentrations occurred during haze episode with lower elevation ratios in all land-use domains compares to non-haze episode. Different characteristics (distribution and range) of the elevation ratios are shown in different land-use domains which highlight the potential local emission hotspots and could have transformative implications for environmental management, thus, contribute to the effectiveness of pollution control strategy.

Management of Patients with Type V Hyperlipoproteinemia: An Uncommon Phenotype of Dyslipidemia with Chylomicronemia and Severe Hypertriglyceridemia.

Hypertriglyceridemia (HTG) remains a risk-enhancing factor of atherosclerotic cardiovascular disease. We aimed to report real-world data on the management of patients with type V hyperlipoproteinemia (HLP5), an uncommon phenotype of dyslipidemia characterized by fasting chylomicronemia and severe HTG. Between July 2018 and May 2021, 90 patients with HTG, including 83 patients with type IV hyperlipoproteinemia (HLP4) and 7 patients with HLP5, were identified by plasma apolipoprotein B (apoB) and lipoprotein electrophoresis. Patients with HLP5 were younger, had higher total cholesterol (TC) (264.9 ± 26.7 mg/dL vs. 183.9 ± 26.1 mg/dL; p < 0.01) and higher triglyceride (TG) (1296.7 ± 380.5 mg/dL vs. 247.6 ± 96.1 mg/dL; p < 0.01), and had lower high-density lipoprotein cholesterol (HDL-C) (30.6 ± 4.8 mg/dL vs. 40.5 ± 8.7 mg/dL; p < 0.01) and lower low-density lipoprotein cholesterol (LDL-C) (62.9 ± 16.4 vs. 103.0 ± 21.1 mg/dL; p < 0.01) compared with patients with HLP4. Despite an aggressive use of statin and fenofibrate with greater reductions in TG (-65.9 ± 13.7% vs. -27.9 ± 30.5%; p < 0.01) following 6 months of treatment, patients with HLP5 had persistent HTG (440.1 ± 239.0 mg/dL vs. 173.9 ± 94.8 mg/dL; p < 0.01) and an increase in LDL-C (28.3 ± 57.2% vs. -19.5 ± 32.0%; p < 0.01) compared with patients with HLP4. Our findings highlight that the lack of novel TG-lowering medications and management guidelines remains an unmet medical need in patients with HLP5. Closely monitoring lipid profiles, full assessment of individual's risk of cardiovascular disease, and emphasis on medication adherence are of clinical importance.

Efficacy of Coxsackievirus A5 Vaccine Candidates in an Actively Immunized Mouse Model.

Coxsackievirus A5 (CV-A5) has recently emerged as a main hand, foot, and mouth disease (HFMD) pathogen. Following a large-scale vaccination campaign against enterovirus 71 (EV-71) in China, the number of HFMD-associated cases with EV-71 was reduced, especially severe and fatal cases. However, the total number of HFMD cases remains high, as HFMD is also caused by other enterovirus serotypes. A multivalent HFMD vaccine containing 4 or 6 antigens of enterovirus serotypes is urgently needed. A formaldehyde-inactivated CV-A5 vaccine derived from Vero cells was used to inoculate newborn Kunming mice on days 3 and 10. The mice were challenged on day 14 with a mouse-adapted CV-A5 strain at a dose that was lethal for 14-day-old suckling mice. Within 14 days postchallenge, groups of mice immunized with three formulations, empty particles (EPs), full particles (FPs), and a mixture of the EP and FP vaccine candidates, all survived, while 100% of the mock-immunized mice died. Neutralizing antibodies (NtAbs) were detected in the sera of immunized mice, and the NtAb levels were correlated with the survival rate of the challenged mice. The virus loads in organs were reduced, and pathological changes and viral protein expression were weak or not observed in the immunized mice compared with those in alum-inoculated control mice. Another interesting finding was the identification of CV-A5 dense particles (DPs), facilitating morphogenesis study. These results demonstrated that the Vero cell-adapted CV-A5 strain is a promising vaccine candidate and could be used as a multivalent HFMD vaccine component in the future.IMPORTANCE The vaccine candidate strain CV-A5 was produced with a high infectivity titer and a high viral particle yield. Three particle forms, empty particles (EPs), full particles (FPs), and dense particles (DPs), were obtained and characterized after purification. The immunogenicities of EP, FP, and the EP and FP mixture were evaluated in mice. Mouse-adapted CV-A5 was generated as a challenge strain to infect 14-day-old mice. An active immunization challenge mouse model was established to evaluate the efficacy of the inactivated vaccine candidate. This animal model mimics vaccination, similar to immune responses of the vaccinated. The animal model also tests protective efficacy in response to the vaccine against the disease. This work is important for the preparation of multivalent vaccines against HFMD caused by different emerging strains.

Evaluation of the Relationship between Momentum Wakes behind Moving Vehicles and Dispersion of Vehicle Emissions Using Near-Roadway Measurements.

A parameterization of initial vertical dispersion coefficient (σz,init) was developed for incorporation into California line source dispersion model, version 4 (CALINE4) and AMS/EPA regulatory model (AERMOD) to better predict pollutant concentrations near roadways. The momentum wake theory of moving vehicles indicates that both vehicle-induced turbulence (VIT) and dispersion occur in the vehicle wake. Based on a literature review, it is postulated that σz,init near roadways can be estimated using a "wake area model" concept of effective wake area defined as the vehicle height times the wake length, vehicle density, and vehicle type. A total of 523 5-min near-roadway simultaneous measurements (2016-2018) of pollutant concentrations and meteorological and traffic information were used to evaluate the model. Two roadways with distinct fleet composition and simple road configurations were selected for monitoring. The near-roadway σz,init ranged from 1 to 4 m for light-duty vehicles (LDVs) and from 3 to 7 m for fleet-mix (LDVs and heavy-duty vehicles (HDVs)). The results demonstrate that the dispersion contribution from one HDV was 31 times larger than that from one LDV. Calculated pollutant dispersion using the wake area model compared favorably with measurements (R2 = 0.91, slope = 1.07). These results indicate that σz,init varies with vehicle density and HDVs. Pollutant dispersion related to the vehicle wakes can be used to correctly parameterize dispersion models and improve prediction of pollutant concentrations near roadways.