Assessment of the Benefits of Targeted Interventions for Pandemic Control in China Based on Machine Learning Method and Web Service for COVID-19 Policy Simulation.

Taking the Chinese city of Xiamen as an example, simulation and quantitative analysis were performed on the transmissions of the Coronavirus Disease 2019 (COVID-19) and the influence of intervention combinations to assist policymakers in the preparation of targeted response measures. A machine learning model was built to estimate the effectiveness of interventions and simulate transmission in different scenarios. The comparison was conducted between simulated and real cases in Xiamen. A web interface with adjustable parameters, including choice of intervention measures, intervention weights, vaccination, and viral variants, was designed for users to run the simulation. The total case number was set as the outcome. The cumulative number was 4,614,641 without restrictions and 78 under the strictest intervention set. Simulation with the parameters closest to the real situation of the Xiamen outbreak was performed to verify the accuracy and reliability of the model. The simulation model generated a duration of 52 days before the daily cases dropped to zero and the final cumulative case number of 200, which were 25 more days and 36 fewer cases than the real situation, respectively. Targeted interventions could benefit the prevention and control of COVID-19 outbreak while safeguarding public health and mitigating impacts on people's livelihood.

Spatiotemporal visualization for the global COVID-19 surveillance by balloon chart.

BACKGROUND: Considering the widespread of coronavirus disease 2019 (COVID-19) pandemic in the world, it is important to understand the spatiotemporal development of the pandemic. In this study, we aimed to visualize time-associated alterations of COVID-19 in the context of continents and countries. METHODS: Using COVID-19 case and death data from February to December 2020 offered by Johns Hopkins University, we generated time-associated balloon charts with multiple epidemiological indicators including crude case fatality rate (CFR), morbidity, mortality and the total number of cases, to compare the progression of the pandemic within a specific period across regions and countries, integrating seven related dimensions together. The area chart is used to supplement the display of the balloon chart in daily new COVID-19 case changes in UN geographic regions over time. Javascript and Vega-Lite were chosen for programming and mapping COVID-19 data in browsers for visualization. RESULTS: From February 1st to December 20th 2020, the COVID-19 pandemic spread across UN subregions in the chronological order. It was first reported in East Asia, and then became noticeable in Europe (South, West and North), North America, East Europe and West Asia, Central and South America, Southern Africa, Caribbean, South Asia, North Africa, Southeast Asia and Oceania, causing several waves of epidemics in different regions. Since October, the balloons of Europe, North America and West Asia have been rising rapidly, reaching a dramatically high morbidity level ranging from 200 to 500/10 000 by December, suggesting an emerging winter wave of COVID-19 which was much bigger than the previous ones. By late December 2020, some European and American countries displayed a leading mortality as high as or over 100/100 000, represented by Belgium, Czechia, Spain, France, Italy, UK, Hungary, Bulgaria, Peru, USA, Argentina, Brazil, Chile and Mexico. The mortality of Iran was the highest in Asia (over 60/100 000), and that of South Africa topped in Africa (40/100 000). In the last 15 days, the CFRs of most countries were at low levels of less than 5%, while Mexico had exceptional high CFR close to 10%. CONCLUSIONS: We creatively used visualization integrating 7-dimensional epidemiologic and spatiotemporal indicators to assess the progression of COVID-19 pandemic in terms of transmissibility and severity. Such methodology allows public health workers and policy makers to understand the epidemics comparatively and flexibly.

Infectivity of Zika virus on primary cells support tree shrew as animal model.

Zika virus (ZIKV) is a mosquito-borne flavivirus that caused the public health emergency. Recently, we have proved a novel small animal tree shrew was susceptive to ZIKV infection and presented the most common rash symptoms as ZIKV patients. Here we further cultured the primary cells from different tissues of this animal to determine the tissue tropism of ZIKV infection in vitro. The results showed that the primary cells from tree shrew kidney, lung, liver, skin and aorta were permissive to ZIKV infection and could support viral replication by the detection of viral specific RNA intra- and extra-cells. In comparing, the skin fibroblast and vascular endothelial cells were highly permissive to ZIKV infection with high releasing of active virus particles in supernatants proved by its infectivity in established neonatal mouse model. The expressions of ZIKV envelop and nonstructural protein-1, and the effects and strong immune response of primary tree shrew cells were also detected followed by ZIKV infection. These findings provide powerful in vitro cell-level evidence to support tree shrew as animal model of ZIKV infection and may help to explain the rash manifestations in vivo.

The African Zika virus MR-766 is more virulent and causes more severe brain damage than current Asian lineage and dengue virus.

The Zika virus (ZIKV) has two lineages, Asian and African, and their impact on developing brains has not been compared. Dengue virus (DENV) is a close family member of ZIKV and co-circulates with ZIKV. Here, we performed intracerebral inoculation of embryonic mouse brains with dengue virus 2 (DENV2), and found that DENV2 is sufficient to cause smaller brain size due to increased cell death in neural progenitor cells (NPCs) and neurons. Compared with the currently circulating Asian lineage of ZIKV (MEX1-44), DENV2 grows slower, causes less neuronal death and fails to cause postnatal animal death. Surprisingly, our side-by-side comparison uncovered that the African ZIKV isolate (MR-766) is more potent at causing brain damage and postnatal lethality than MEX1-44. In comparison with MEX1-44, MR-766 grows faster in NPCs and in the developing brain, and causes more pronounced cell death in NPCs and neurons, resulting in more severe neuronal loss. Together, these results reveal that DENV2 is sufficient to cause smaller brain sizes, and suggest that the ZIKV African lineage is more toxic and causes more potent brain damage than the Asian lineage.

[Agrobacterium tumefaciens-mediated transformation of the pathogen of Botrytis cinerea].

Employing gfp as a reporter gene and hygromycin gene (hph) as a selection marker, the recombinant vector pKPG was constructed and transformed into fresh conidia of Botrytis cinerea via Agrobacterium tumefaciens. Transformants were identified by PCR analysis of gfp and hph cassette, green fluorescence observation with microscope and Southern hybridization. Results confirmed that target genes were successfully integrated into the genome of Botrytis cinerea.

[Cloning and analysis of adenine nucleotide translocase gene in Helicoverpa armigera].

A cDNA clone encoding the ADP/ATP translocase in Helicoverpa armigera has been identified by RT-PCR, 5'and 3'RACE methods. Sequence analysis shows that it is 1,190 bp long and contains a single open reading frame (ORF, 133-1,033 bp) encoding a protein of 300 amino acids (GenBank submission number, AY253868). The protein has a 22 aa signal peptide on its N-terminal, which leads the protein locating onto the inner membrane of the mitochondria. It also has three conserved domains of the mitochondrial carrier protein forming a channel to exchange ATP and ADP energy molecule through the inner membrane of the mitochondria. It shows extensive similarities to the known ADP/ATP translocase poly-peptides. The ADP/ATP translocase similarity was up to 90% in the Lepidoptera.

[Cloning and structural analysis of MLP in the silkworm, Bombyx mori].

The LIM domain is found in a wide variety of eukaryotic proteins that regulate gene expression and cell differentiation during development. Muscle LIM protein (MLP) gene in Bombyx mori has been cloned by blasting its EST database and PCR test in present report. The resulting sequence covers 2 327 bp of cDNA (GenBank accession No. DQ311195). It has a complete open reading fragment and encodes a 494 amino acid protein. Genomic DNA sequence contains 11 exons and 10 introns, with intron splicing following the GT-AG rule. M.W. and PI of the predicted MLP in Bombyx mori are 53.03 kDa and 8.29 respectively. A single LIM domain linked to a glyscine-rich region is found in a previously deposited LIM protein (AAR23823) in Bombyx mori. MLP identified in this report encodes a protein with five tandem LIM-glycine modules. The two LIM proteins could be produced by alternative splicing and both are probably involved in muscle cell differentiation. This work provides foundation for further research on the in vivo function of MLP.

Conceptual model for automatic early warning information system of infectious diseases based on internet reporting surveillance system.

OBJECTIVE: To establish a conceptual model of automatic early warning of infectious diseases based on internet reporting surveillance system, with a view to realizing an automated warning system on a daily basis and timely identifying potential outbreaks of infectious diseases. METHODS: The statistic conceptual model was established using historic surveillance data with movable percentile method. RESULTS: Based on the infectious disease surveillance information platform, the conceptual model for early warning was established. The parameter, threshold, and revised sensitivity and specificity of early warning value were changed to realize dynamic alert of infectious diseases on a daily basis. CONCLUSION: The instructive conceptual model of dynamic alert can be used as a validating tool in institutions of infectious disease surveillance in different districts.

[A preliminary analysis of the function of the OsRab5a gene in rice (Oryza sativa L.)].

OsRab5a encodes a Rab5 protein in rice, which belongs to the Rab family of small GTP-binding protein superfamily. Transgenic plants with POsrab5a::beta-glucuronidase (GUS) gene indicate that OsRab5a is expressed in callus, root, stem, leaf, root base and spikelet (Figs.1, 2H-1). Using the transgenic Arabidopsis with fused gene of GFP::OsRab5a and GFP::OsRab5aCA and by using FM4-64 (the lipophilic styryl dye) staining, we have demonstrated that OsRab5a is involved in vesicular transport and GFP-OsRab5a is localized on the plasma membrane and early endosomes (Fig.2A-C), while GFP-OsRab5aCA is localized in the cell membrane (Fig.2D-F). The reduction of expression of OsRab5a in callus RNA interference, however, led to the lethality of callus during differentiation (Fig.3D-F). The expression of OsRab5a was upregulated slightly by exogenous cytokinin (Fig.4), and was higher in the differentiation medium than that in selection medium (Fig.3G-I). These results suggest that OsRab5a plays an important role in callus differentiation probably through mediating hormone signal transduction.

A CHASE domain containing protein kinase OsCRL4, represents a new AtCRE1-like gene family in rice.

AtCRE1 is known to be a cytokinin receptor in Arabidopsis. The AtCRE1 protein contains CHASE domain at the N-terminal part, followed by a transmitter (histidine kinase) domain and two receiver domains. The N-terminal CHASE domain of AtCRE1 contains putative recognition sites for cytokinin. Five CHASE domains containing proteins were found in rice, OsCRL1a, OsCRL1b, OsCRL2, OsCRL3, and OsCRL4. OsCRL1a, OsCRL1b, OsCRL2 and OsCRL3 contain the four domains existing in CRE1, whereas OsCRL4 only contains the CHASE domain and a putative Ser/Thr protein kinase domain. The authors cloned the encoding gene OsCRL4 and found that it represents a new member of the cytokinin receptor protein in rice.