[Establishment of index system for population based SARS-CoV-2 nucleic acid screening]

Objective: To establish an index system of population based SARS-CoV-2 nucleic acid screening, and provide reference to determine the screening coverage appropriately. Methods: The literature review and brain storming sessions were used to develop the basic frame and index system of population based SARS-CoV-2 nucleic acid screening. Based on Delphi method and Analytic Hierarchy Process, 21 domestic experts were selected for two rounds of consultation to determine the index system of population based SARS-CoV-2 nucleic acid screening and its weight. Results: The positive indexes of experts in two rounds of consultations were both 100%. The experts' authority coefficients (Cr) were 0.88±0.08 and 0.89±0.07, respectively. And the range of coefficient of variation (CV) were (0.08, 0.24), (0.09, 0.25). The Kendall's W coordination coefficients were 0.34 and 0.22 respectively, which were statistically significant. The index system of population based SARS-CoV-2 nucleic acid screening was established, which had 4 first-level indexes, 11 second-level indexes and 58 third-level indexes. Besides, the weight of each index was determined. Conclusion: The index system of population based SARS-CoV-2 nucleic acid screening has been established, which can provide scientific reference for the health administration to determine the coverage of population based SARS-CoV-2 nucleic acid screening when local COVID-19 epidemic occurs.

Acceleration of Brain TOF-MRA with Compressed Sensitivity Encoding: A Multicenter Clinical Study

BACKGROUND AND PURPOSE

The clinical practice of three-dimensional TOF-MRA, despite its capability in brain artery assessment, has been hampered by the relatively long scan time, while recent developments in fast imaging techniques with random undersampling has shed light on an improved balance between image quality and imaging speed. Our aim was to evaluate the effectiveness of TOF-MRA accelerated by compressed sensitivity encoding and to identify the optimal acceleration factors for routine clinical use.

MATERIALS AND METHODS

One hundred subjects, enrolled at 5 centers, underwent 8 brain TOF-MRA sequences: 5 sequences using compressed sensitivity encoding with acceleration factors of 2, 4, 6, 8, and 10 (CS2, CS4, CS6, CS8, and CS10), 2 using sensitivity encoding with factors of 2 and 4 (SF2 and SF4), and 1 without acceleration as a reference sequence (RS). Five large arteries, 6 medium arteries, and 6 small arteries were evaluated quantitatively (reconstructed signal intensity, structural similarity, contrast ratio) and qualitatively (scores on arteries, artifacts, overall image quality, and diagnostic confidence for aneurysm and stenosis). Comparisons were performed among the 8 sequences.

RESULTS

The quantitative measurements showed that the reconstructed signal intensities of the assessed arteries and the structural similarity consistently decreased as the compressed sensitivity encoding acceleration factor increased, and no significant difference was found for the contrast ratios in pair-wise comparisons among SF2, CS2, and CS4. Qualitative evaluations showed no significant difference in pair-wise comparisons among RS, SF2, and CS2 (P > .05). The visualization of all the assessed arteries was acceptable for CS2 and CS4, while 2 small arteries in images of CS6 were not reliably displayed, and the visualization of large arteries was acceptable in images of CS8 and CS10.

CONCLUSIONS

CS4 is recommended for routine brain TOF-MRA with balanced image quality and acquisition time; CS6, for examinations when small arteries are not evaluated; and CS10, for fast visualization of large arteries.

Artificial intelligence-assisted reduction in patients' waiting time for outpatient process: a retrospective cohort study

Background

Many studies suggest that patient satisfaction is significantly negatively correlated with the waiting time. A well-designed healthcare system should not keep patients waiting too long for an appointment and consultation. However, in China, patients spend notable time waiting, and the actual time spent on diagnosis and treatment in the consulting room is comparatively less.

Methods

We developed an artificial intelligence (AI)-assisted module and name it XIAO YI. It could help outpatients automatically order imaging examinations or laboratory tests based on their chief complaints. Thus, outpatients could get examined or tested before they went to see the doctor. People who saw the doctor in the traditional way were allocated to the conventional group, and those who used XIAO YI were assigned to the AI-assisted group. We conducted a retrospective cohort study from August 1, 2019 to January 31, 2020. Propensity score matching was used to balance the confounding factor between the two groups. And waiting time was defined as the time from registration to preparation for laboratory tests or imaging examinations. The total cost included the registration fee, test fee, examination fee, and drug fee. We used Wilcoxon rank-sum test to compare the differences in time and cost. The statistical significance level was set at 0.05 for two sides.

Results

Twelve thousand and three hundred forty-two visits were recruited, consisting of 6171 visits in the conventional group and 6171 visits in the AI-assisted group. The median waiting time was 0.38 (interquartile range: 0.20, 1.33) hours for the AI-assisted group compared with 1.97 (0.76, 3.48) hours for the conventional group (p < 0.05). The total cost was 335.97 (interquartile range: 244.80, 437.60) CNY (Chinese Yuan) for the AI-assisted group and 364.58 (249.70, 497.76) CNY for the conventional group (p < 0.05).

Conclusions

Using XIAO YI can significantly reduce the waiting time of patients, and thus, improve the outpatient service process of hospitals.

Is there possibility of vertical transmission of COVID-19: a systematic review

In order to investigate the clinical features of pregnant women and their neonates with coronavirus disease 2019 (COVID-19) and the evidence of vertical transmission of COVID-19, we retrieved studies included in PubMed, Medline and Chinese databases from January 1, 2000 to October 25, 2020 using relevant terms, such as 'COVID-19', 'vertical transmission' et al. in 'Title/Abstract'. Case reports and case series were included according to the inclusion and exclusion criteria. We conducted literature screening and data extraction, and performed literature bias risk assessment. Total of 13 case series and 16 case reports were collected, including a total of 564 pregnant women with COVID-19 and their 555 neonates, of which 549 neonates received nucleic acid test for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and 18 neonates was diagnosed with COVID-19. The positive rate is 3.28%. Amniotic fluid of one woman was tested positive for SARS-CoV-2. The majority of infected neonates were born under strict infection control and received isolation and artificial feeding. Up till now, there is no sufficient evidence to exclude the possibility of vertical transmission for COVID-19 based on the current available data.

Krüppel-like factor 6 promotes odontoblastic differentiation through regulating the expression of dentine sialophosphoprotein and dentine matrix protein 1 genes

AIM

To investigate the potential role of Krüppel-like factor 6 (KLF6) in the odontoblastic differentiation of immortalized dental papilla mesenchymal cells (iMDP-3) cells.

METHODOLOGY

Alizarin Red S (ARS) and Alkaline phosphatase (ALP) staining was used to examine the mineralization effect of iMDP-3 cells after odontoblastic induction. Real-time PCR and Western blotting were employed to analyse dentine sialophosphoprotein (DSPP), dentine matrix protein 1 (DMP1), RUNX family transcription factor 2 (RUNX2), ALP and KLF6 expression during this process. Co-expression of the KLF6 with DMP1, DSPP and RUNX2 was detected by double immunofluorescence staining to explore their local relationship in the cell. To further investigate KLF6 functions, Klf6 gain- and loss-of-function assays followed by ARS and ALP stainings, real-time PCR and Western blotting were performed using Klf6-overexpression plasmids and Klf6 siRNA to investigate whether changes in Klf6 expression affect the odontoblastic differentiation of iMDP-3 cells. Dual-luciferase reporter assays were used to elucidate the mechanistic regulation of Dspp and Dmp1 expression by Klf6. Means were compared using the unpaired t-test and Kruskal-Wallis one-way anova with P < 0.05 and P < 0.01 defined as statistical significance levels.

RESULTS

The expression levels of Klf6 (P < 0.01), Dspp (P < 0.05), Dmp1 (P < 0.01), Runx2 (P < 0.01) and Alp (P < 0.01) were significantly elevated during odontoblastic differentiation of iMDP-3 cells. KLF6 was co-localized with DSPP, DMP1 and RUNX2 in the cytoplasm and nucleus of iMDP-3 cells. Overexpression of Klf6 promoted the odontoblastic differentiation of iMDP-3, whereas the inhibition of Klf6 prevented this procession. Dual-luciferase assays revealed that Klf6 upregulates Dspp and Dmp1 transcription in iMDP-3 cells during odontoblastic differentiation.

CONCLUSION

Klf6 promoted odontoblastic differentiation by targeting the transcription promoter of Dmp1 and Dspp. This study may offer novel insights into strategies for treating injuries to dental pulp tissue.

[Clinical analysis of 11 cases of sub-acute arsenic poisoning]

Objective: To investigate the clinical manifestations, treatments and prognosis of subacute arsenic poisoning. Methods: In January 2020, a retrospective analysis was carried out on 11 patients hospitalized with subacute arsenic poisoning caused by arsenic contaminated drinking water. We observed manifestations, treatments and prognosis. Results: The main clinical presentations of subacute arsenic poisoningin were gastroenteritis in early phase, some of them had other organ damage, such as skin, blood, liver, kidney, cardiovascular and so on. The later phase was mainly peripheral nervous system damage. The treatment was mainly to chelate arsenic, protect target organs and treat toxic peripheral neuropathy. Most were significantly recoveried, but the recovery of severe toxic peripheral neuropathy was tardy. Conclusion: Acute gastroenteritis is the mainly early manifestation of subacute arsenic poisoning caused by digestive tract, and toxic peripheral neuropathy in the later phase. The prognosis is good, but the recovery of severe toxic peripheral neuropathy is tardy.

Artificial intelligence-assisted auscultation in detecting congenital heart disease

Aims

Computer-assisted auscultation has become available to assist clinicians with physical examinations to detect congenital heart disease (CHD). However, its accuracy and effectiveness remain to be evaluated. This study seeks to evaluate the accuracy of auscultations of abnormal heart sounds of an artificial intelligence-assisted auscultation (AI-AA) platform we create.

Methods and results

Initially, 1397 patients with CHD were enrolled in the study. The samples of their heart sounds were recorded and uploaded to the platform using a digital stethoscope. By the platform, both remote auscultation by a team of experienced cardiologists from Shanghai Children's Medical Center and automatic auscultation of the heart sound samples were conducted. Samples of 35 patients were deemed unsuitable for the analysis; therefore, the remaining samples from 1362 patients (mean age-2.4 ± 3.1 years and 46% female) were analysed. Sensitivity, specificity, and accuracy were calculated for remote auscultation compared to experts' face-to-face auscultation and for artificial intelligence automatic auscultation compared to experts' face-to-face auscultation. Kappa coefficients were measured. Compared to face-to-face auscultation, remote auscultation detected abnormal heart sound with 98% sensitivity, 91% specificity, 97% accuracy, and kappa coefficient 0.87. AI-AA demonstrated 97% sensitivity, 89% specificity, 96% accuracy, and kappa coefficient 0.84.

Conclusions

The remote auscultations and automatic auscultations, using the AI-AA platform, reported high auscultation accuracy in detecting abnormal heart sound and showed excellent concordance to experts' face-to-face auscultation. Hence, the platform may provide a feasible way to screen and detect CHD.

Development and Evaluation of a Leukemia Diagnosis System Using Deep Learning in Real Clinical Scenarios

Leukemia is the most common malignancy affecting children. The morphologic analysis of bone marrow smears is an important initial step for diagnosis. Recent publications demonstrated that artificial intelligence is able to classify blood cells but a long way from clinical use. A total of 1,732 bone marrow images were used for the training of a convolutional neural network (CNN). New techniques of deep learning were integrated and an end-to-end leukemia diagnosis system was developed by using raw images without pre-processing. The system creatively imitated the workflow of a hematologist by detecting and excluding uncountable and crushed cells, then classifying and counting the remain cells to make a diagnosis. The performance of the CNN in classifying WBCs achieved an accuracy of 82.93%, precision of 86.07% and F1 score of 82.02%. And the performance in diagnosing acute lymphoid leukemia achieved an accuracy of 89%, sensitivity of 86% and specificity of 95%. The system also performs well at detecting the bone marrow metastasis of lymphoma and neuroblastoma, achieving an average accuracy of 82.93%. This is the first study which included a wider variety of cell types in leukemia diagnosis, and achieved a relatively high performance in real clinical scenarios.

Association between vaccinations and clinical manifestations in children with COVID-19

BACKGROUND

The infection rate of Coronavirus Disease 2019 (COVID-19) in children was less than that in adults. However, the underlining reason is not well known.

METHODS

Children with COVID-19 were recruited from two Children's Hospitals in Wuhan and Shanghai in this case-control study. The associations of initial symptoms with age, vaccinations of Bacillus Calmette Guerin (BCG), and influenza and pathogens were determined by Chi-square t-test.

RESULTS

We evaluated 248 confirmed cases, and 56 suspected cases with COVID-19. The median age was 6.82 years old, and 118 cases (38.82%) were girls. Furthermore, 30.26% of all patients were asymptomatic cases. The percentage of asymptomatic cases vaccinated with BCG was not significantly higher than that without BCG vaccination [86/280 (30.71%) vs. 6/13 (46.15%), P=0.203], and initial symptoms were not related with immunized influenza vaccine (P=0.267). Compared to parameters in pediatric patients with normal body temperatures, patients with fever had higher C reactive protein (CRP) (P<0.001).

CONCLUSIONS

Pediatric COVID-19 patients with BCG vaccinations exhibit similar clinical manifestations compared to those without BCG vaccinations, and the severity of symptoms in pediatric patients may be related to the maturity of immune function.

[Epidemiological characteristics of imported COVID-19 cases in Guangzhou]

Objective: To understand the epidemiological characteristics of imported COVID-19 cases in Guangzhou and provide scientific basis for the prevention and control of the disease. Methods: The data of imported COVID-19 in Guangzhou reported as of April 1, 2020 were collected from National Notifiable Disease Report System of China. The software Excel 2010 and SPSS 19.0 were applied for data cleaning and statistical analysis. Results: As of April 1, 2020, a total of 103 imported COVID-19 cases had been reported in Guangzhou, in which 92 were confirmed cases and 11 were asymptomatic infection cases. The number of the confirmed imported cases accounted for 11.4% (92/806) in of the total in China at the same time. The male to female ratio of the cases was 1.58∶1 (63∶40). The median age of the cases was 31 years (P(25)-P(75):22-40 years), range of age was 11-63 years. The main occupational distributions of the cases were business services (41/103, 39.8%) and students (36/103, 35.0%). The imported cases whose destinations were 19 provinces and municipalities rather than Guangdong after entering the country accounted for 43.7%. The main source countries of infections were the United Kingdom (27/103, 26.2%), the Philippines (13/103, 12.6%), the United States (13/103, 12.6%) and Nigeria (7/103, 6.8%). There were 34 inbound flights from which the imported COVID-19 cases were detected, in which 10 flights (10/34, 29.4%) were found to carry more than 3 cases, with an average voyage time of (11.14±0.53) hours. A total of 29 imported cases(28.2%) showed symptoms before entering the country, and 65 cases (63.1%) had been isolated before the onset of the disease. The mean free activity time of the isolated cases after the onset was (6.76±0.79) days. The average number of the imported cases' close contacts was 53. There were 13 clusters of COVID-19 caused by the imported cases, involving 36 cases (including 1 imported associated case). Conclusions: The sources of the imported COVID-19 cases in Guangzhou were widely distributed, and no cases had been found to be infected on the flights. In the early stage of the imported epidemic, there was high risk for the spread of the epidemic. Strengthened prevention and control of imported COVID-19 effectively reduced the of transmission risk of COVID-19 in communities.

[Risk prevention of plague and suggestions for coping in China]

Plague is listed by the WHO as one of 20 infectious diseases that have re-emerged. Plague was prevalent in the world, bringing great disaster to the people around the world. Nowadays, great achievements have been made in the prevention and control of plague in our country. Human plague in China is currently sporadic, but there are still risks of resurgence spread and importation. This paper reviews the incidence of human plague globally and in China in the past ten years, summarizes the characteristics of current plague epidemic globally and in China, analyzes the current risks of plague prevention in China, and puts forward relevant countermeasures.

MicroRNA-579-3p promotes the progression of osteoporosis by inhibiting osteogenic differentiation of mesenchymal stem cells through regulating Sirt1

OBJECTIVE

To explore whether microRNA-579-3P was involved in the development of osteoporosis, and to investigate the possible molecular mechanisms.

PATIENTS AND METHODS

The messenger RNA (mRNA) expression levels of microRNA-579-3P, alkaline phosphatase (ALP), runt-related transcription factor 2 (RUNX2) and bone sialoprotein (BSP) in serum samples of osteoporosis patients and normal controls were detected by quantitative Real-time polymerase chain reaction (qRT-PCR), respectively. Meanwhile, the expressions of the above genes during osteogenic differentiation of human bone marrow mesenchymal stem cells (hMSCs) were examined as well. To investigate the effect of microRNA-579-3P on osteogenesis, microRNA-579-3P was overexpressed and knocked down in hMSCs. Subsequently, the mRNA and protein expression levels of osteogenesis-related genes, such as ALP, RUNX2 and BSP, were detected by qRT-PCR and Western blot, respectively. In addition, ALP activity and mineralization forming ability were evaluated by ALP staining and alizarin red staining. Bioinformatics predicted that Sirt1 was the target gene of microRNA-579-3P. Subsequent luciferase reporter gene assay was performed to verify the binding relationship of microRNA-579-3P to Sirt1. Meanwhile, qRT-PCR and Western blot were used to detect the changes in the mRNA and protein expression levels of Sirt1, respectively. After overexpression of microRNA-579-3P and Sirt1, qRT-PCR, Western blot, ALP staining and alizarin red staining assays were performed to detect the osteogenic differentiation of hMSCs.

RESULTS

The expression of microRNA-579-3P in serum of patients with osteoporosis was significantly higher than that of normal controls. Meanwhile, the expression of microRNA-579-3P decreased gradually during osteogenic differentiation of hMSCs. Overexpression of microRNA-579-3P significantly reduced the expressions of osteogenic related genes, including ALP, RUNX2 and BSP. Besides, ALP activity and mineralized nodule formation ability decreased obviously as well. Luciferase reporter gene assay showed that microRNA-579-3P could bind to Sirt1. After overexpression of microRNA-579-3P, the mRNA and protein expression levels of Sirt1 were significantly reduced, which were reversed after silence of microRNA-579-3P. Simultaneous overexpression of microRNA-579-3P and Sirt1 could reverse the inhibition of osteogenic differentiation of hMSCs caused by overexpression of microRNA-579-3P alone.

CONCLUSIONS

MicroRNA-579-3P could inhibit osteogenic differentiation of hMSCs by regulating Sirt1, thereby promoting the development of osteoporosis.