High-Throughput Characterization of Cell Adhesion Strength Using Long-Channel Constriction-Based Microfluidics

The adhesion strength of a cancer cell is a valuable biophysical marker of its metastatic potential, tightly associated with various metastatic processes; for example, cancer cells escape from a primary tumor, and circulating tumor cells (CTCs) are anchored to the vessel wall. Although constriction-based microfluidics can realize the high-throughput characterization of single-cell deformability, due to the influence of cell size heterogeneity, accurately evaluating the adhesion strength of a cancer cell at high throughputs in constriction remains difficult. In this paper, we first proposed an approach for the assessment of adhesion strength of BGC-823 and SGC-7901 cell lines at high throughputs based on a friction coefficient using the constant velocity stage of cell transit in a long-channel constriction. Cell size was proven to be independent of adhesion strength by cell detachment assay; however, it has large effects on cell transit velocity in constriction. Therefore, the linear elasticity of a completely deformed cell in constriction is simplified as a compressed spring model, effectively reducing the influence of cell size heterogeneity. Theoretically, our proposed model can well offset the influence of cell size by cell transit velocity, while our experimental results indicate that the friction coefficient has a good linear relationship with the logarithm of the adhesion strength too. Therefore, our proposed approach can realize accurate characterization of cell adhesion strength at high throughputs using long-channel constriction-based microfluidics. Hence, this work might enrich the functions of constriction-based microfluidics and bring new insights into the characterization of mechanical phenotypes.

Shock Ignition Laser-Plasma Interactions in Ignition-Scale Plasmas

We use a subignition scale laser, the 30 kJ Omega, and a novel shallow-cone target to study laser-plasma interactions at the ablation-plasma density scale lengths and laser intensities anticipated for direct drive shock-ignition implosions at National Ignition Facility scale. Our results show that, under these conditions, the dominant instability is convective stimulated Raman scatter with experimental evidence of two plasmon decay (TPD) only when the density scale length is reduced. Particle-in-cell simulations indicate this is due to TPD being shifted to lower densities, removing the experimental back-scatter signature and reducing the hot-electron temperature. The experimental laser energy-coupling to hot electrons was found to be 1%-2.5%, with electron temperatures between 35 and 45 keV. Radiation-hydrodynamics simulations employing these hot-electron characteristics indicate that they should not preheat the fuel in MJ-scale shock ignition experiments.

Selective optogenetic stimulation of glutamatergic, but not GABAergic, vestibular nuclei neurons induces immediate and reversible postural imbalance in mice

Glutamatergic and GABAergic neurons represent the neural components of the medial vestibular nuclei. We assessed the functional role of glutamatergic and GABAergic neuronal pathways arising from the vestibular nuclei (VN) in the maintenance of gait and balance by optogenetically stimulating the VN in VGluT2-cre and GAD2-cre mice. We demonstrate that glutamatergic, but not GABAergic VN neuronal subpopulation is responsible for immediate and strong posturo-locomotor deficits, comparable to unilateral vestibular deafferentation models. During optogenetic stimulation, the support surface dramatically increased in VN^VGluT2+ mice, and rapidly fell back to baseline after stimulation, whilst it remained unchanged during similar stimulation of VN^GAD2+ mice. This effect persisted when vestibular tactilo kinesthesic plantar inputs were removed. Posturo-locomotor alterations evoked in VN^VGluT2+ animals were still present immediately after stimulation, while they disappeared 1 h later. Overall, these results indicate a fundamental role for VN^VGluT2+ neurons in balance and posturo-locomotor functions, but not for VN^GAD2+ neurons, in this specific context. This new optogenetic approach will be useful to characterize the role of the different VN neuronal populations involved in vestibular physiology and pathophysiology.

Increasing fasting glucose and fasting insulin associated with elevated bone mineral density-evidence from cross-sectional and MR studies

We performed a cross-sectional study using the National Health Examination and Nutrition Survey (NHANES) data and a Mendelian randomisation (MR) study using the GWAS summary statistics from European populations. The T2D-related indices (fasting plasma glucose (FPG), fasting insulin (FI), and insulin resistance (IR)) were found to associate with elevated bone mineral density (BMD).

INTRODUCTION

The known associations amongst FPG, FI, IR, and BMD remain inconsistent. This study aims to explore the abovementioned associations by using cross-sectional and MR designs.

METHODS

Data from adults aged ≥ 20 years (n = 7170) in four rounds of the U.S. NHANES (2005-2010 and 2013-2014) were analysed in this cross-sectional study. Multiple linear and logistic regression models were used for statistical analyses. A two-sample MR study was performed using the genome-wide association study summary statistics obtained from the Meta-analyses of Glucose and Insulin-related traits Consortium (n = 108,557) and Genetic Factors for Osteoporosis Consortium (n = 32,735) to examine the causality of the FI-BMD association.

RESULTS

Multiple linear regression revealed that FPG was positively associated with the BMDs at the hip, femur neck, and 1st lumbar spine (L1). Multiple logistic regressions revealed that FPG levels were associated with elevated BMDs at the hip and L1, and FI and IR levels were associated with elevated BMD at the hip. Patients with type 2 diabetes had higher hip BMD than those without diabetes. In the MR study, the lumbar spine BMD increased by 0.49 g/cm² (95% confidence interval: 0.01, 0.97) in response to per unit increase in log-transformed FI.

CONCLUSION

Findings from our cross-sectional and MR studies revealed the associations between the studied diabetic indices and BMD measurements in the US and European adults.

Short-term interaction between silent and devastating earthquakes in Mexico

Either the triggering of large earthquakes on a fault hosting aseismic slip or the triggering of slow slip events (SSE) by passing seismic waves involve seismological questions with important hazard implications. Just a few observations plausibly suggest that such interactions actually happen in nature. In this study we show that three recent devastating earthquakes in Mexico are likely related to SSEs, describing a cascade of events interacting with each other on a regional scale via quasi-static and/or dynamic perturbations across the states of Guerrero and Oaxaca. Such interaction seems to be conditioned by the transient memory of Earth materials subject to the "traumatic" stress produced by seismic waves of the great 2017 (Mw8.2) Tehuantepec earthquake, which strongly disturbed the SSE cycles over a 650 km long segment of the subduction plate interface. Our results imply that seismic hazard in large populated areas is a short-term evolving function of seismotectonic processes that are often observable.

How to Choose a Proper Theoretical Analysis Model Based on Cell Adhesion and Nonadhesion Impedance Measurement

The accurate equivalent circuit model contributes to the better fitting of required cell characteristics, such as cell impedance, cell adhesion area, and cell-electrode distance. However, so many theoretical models on specific modules make it difficult for new researchers to understand the whole model of electrode system physically. Besides, the accurate theoretical model and the simplified calculations obviously contradict each other; therefore, it is confusing for many researchers to choose the proper theoretical model to calculate the specific parameters required. In this review, we first discuss the problems and suggestions of electrode system design for cell adhesion-based measurement in terms of parasitic capacitance, detection range of cell number, electric field distribution, and interelectrode distance. The design of electrode system for cell nonadhesion measurement was analyzed in terms of microchannel size and electrode position. Then, we discuss the advantages and disadvantages of various equivalent circuit models according to different requirements of researchers, and simultaneously provide a corresponding theoretical model for researchers. Various factors influencing electric impedance spectroscopy (EIS) such as the parasitic capacitance between microelectrodes, the changes of cell adhesion area and cell-electrode distance, the electrode geometry, and the surface conductivity of electrode were quantitatively analyzed to contribute to better understanding of the equivalent models. Finally, we gave advice to optimize the theoretical models further and perspectives on building uniform principles of theoretical model optimization in the future.

Evaluating cell viability heterogeneity based on information fusion of multiple adhesion strengths

Cell viability evaluation is significantly meaningful for cellular assays. Some cells with weak viability are easily killed in the detection of anticancer drugs, while others with strong viability survive and proliferate, ultimately leading to the treatment failure or the inaccuracy of biological assays. Accurately evaluating cell viability heterogeneity still remains difficult. This article proposed a multiphysical property information fusion method for evaluating cell viability heterogeneity based on polynomial regression in a single-channel integrated microfluidic chip. In this method, adhesion strengths τ_N , that are defined as the magnitude of shear stress needed to detach (100 - N) % of cell population, were extracted as the independent variables of polynomial regression model by calculating the nonlinear fitting of the impedance-response curves for shear stress (cell detachment assay). Besides, by calculating the nonlinear fitting of the drug dose-response curves for cancer cells (IC₅₀ assay), the half-maximal inhibitory concentration (IC₅₀ ) was extracted as the dependent variables of polynomial regression model. The results show that the mean relative error of our fusion method averagely reduces by 6.04% and 62.79% compared with the multiple linear regression method and the cell counting method. Moreover, a simplified theoretical model used to describe the quantitative relationship between cell viability and its adhesion strengths was built to provide a theoretical basis for our fusion method.

The protective effect of hesperidin against renal ischemia-reperfusion injury involves the TLR-4/NF-κB/iNOS pathway in rats

Renal injury is reported to have a high mortality rate. Additionally, there are several limitations to current conventional treatments that are used to manage it. This study evaluated the protective effect of hesperidin against ischemia/reperfusion (I/R)-induced kidney injury in rats. Renal injury was induced by generating I/R in kidney tissues. Rats were then treated with hesperidin at a dose of 10 or 20 mg/kg intravenously 1 day after surgery for a period of 14 days. The effect of hesperidin on renal function, serum mediators of inflammation, and levels of oxidative stress in renal tissues were observed in rat kidney tissues after I/R-induced kidney injury. Moreover, protein expression and mRNA expression in kidney tissues were determined using Western blotting and RT-PCR. Hematoxylin and eosin (H&E) staining was done for histopathological observation of kidney tissues. The data suggest that the levels of blood urea nitrogen (BUN) and creatinine in the serum of hesperidin-treated rats were lower than in the I/R group. Treatment with hesperidin also ameliorated the altered level of inflammatory mediators and oxidative stress in I/R-induced renal-injured rats. The expression of p-IκBα, caspase-3, NF-κB p65, Toll-like receptor 4 (TLR-4) protein, TLR-4 mRNA, and inducible nitric oxide synthase (iNOS) was significantly reduced in the renal tissues of hesperidin-treated rats. Histopathological findings also revealed that treatment with hesperidin attenuated the renal injury in I/R kidney-injured rats. In conclusion, our results suggest that hesperidin protects against renal injury induced by I/R by involving TLR-4/NF-κB/iNOS signaling.

A novel method of cell culture based on the microfluidic chip for regulation of cell density

The regulation of cell density is an important segment in microfluidic cell culture, particularly in the repeated assays. Traditionally, consistent cell density is difficult to achieve, owing to the inaccurate regulation of cell density with manual feedback. A novel cell culture method with automatic feedback is proposed for real-time regulation of cell density based on microfluidic chip in this paper. Here, an integrated microfluidic system combining cell culture, density detection, and control of proliferation rate was developed. Interdigital electrode structures were sputtered on the microchannel automatically to provide the real-time feedback information of impedance. The most sensitive frequency was studied to improve the detection resolution of the sensing chip. Cells were cultured on the chip surface and cell density was detected by monitoring the alternation of the impedance. The feedback controller was established by the least squares support vector machines. Then, the cell proliferation rate was automatically controlled using the feedback controller to achieve the desired cell density in the repeated assays. The results show that the standard error of this method is 2.8% indicating that the method can keep a consistency of cell density in the repeated assays. This study provides a basis for improving the accuracy and repeatability in the further assays of finding the optimal drug concentration.

Lensfree Diffraction Reconstruction Approach Enables Early Detection of Cancer In Vitro Based on Molecular Diagnosis

Before there are any megascopic cancer clinical symptoms, molecular diagnosis is the main method for detecting cancer-associated gene and tumor marker. The existing detection facilities are all expensive, complicated to operate, and time-consuming, thereby making them difficult to popularize and benefit humans. In this study, we proposed a high-throughput and cost-effective approach, which enables accurate detection of extremely rare cancer cells based on molecular diagnosis of target tumor marker and a lensfree diffraction imaging platform. This approach achieves high-speed and high-quality reconstruction of huge images, which well solves the problem that precise recognition is almost impossible utilizing raw image because of significant pattern magnification and serious overlaps. Furthermore, the cells which are labeled with immune microbeads can be screened using the determined covered pixel sets, which are extracted in different focus reconstruction planes. The recognition strategy is implemented based on set intersection. With this method, the target cancer cells can be rapidly and accurately screened in a large number of benign cell samples. Besides, the detection equipment is cost-effective and easy to operate and popularize. It is expected to be widely used as a diagnostic tool for early detection of cancer.

Lipid status and linear relationship between total cholesterol and triglycerides in glycogen storage disease type I

OBJECTIVE

Glycogen storage disease type Ia (GSDIa) is a glucose metabolic disorder. GSDIa patients are characterized by hypoglycemia, hepatomegaly, hyperlipidemia, and hyperlactacidemia. This retrospective study aimed to review the lipid status, explore lipid treatment targets, and assess preferable lipid-lowering drugs.

PATIENTS AND METHODS

Clinical data on GSDIa patients' characteristics were collected. Most patients were followed-up once a year. Diet control and raw cornstarch treatment were used to maintain normal blood glucose and lipid levels. Some patients were given lipid-lowering drugs. We compared the lipid levels before and after each treatment.

RESULTS

A total of 163 GSDIa patients were enrolled in this study. After treatment with raw cornstarch, the total triglycerides (TG) level has significantly decreased by 30±50% (8.37±7.23 to 5.39±5.29 mmol/L, p<0.001). There was no change in the total cholesterol (TC) level. Fifteen patients regularly took atorvastatin, and 15 took fibrates for more than one year. The therapeutic effect of atorvastatin was better than fibrates. The TC was positively correlated with TG after treatment, resulting in the following linear equation: TG=1.63×TC-2.86. Using this equation and Chinese children's normal TC level of 5.18 mmol/L, we aimed to maintain the patients at TG < 5.58 mmol/L.

CONCLUSIONS

Patients with GSDIa have significant abnormalities in lipid metabolism. Because the complications of hyperlipidemia are caused mainly by TC, thereby, by maintaining it at a normal level, we could set a TG target by the linear equation that allowed a certain degree of hypertriglyceridemia. This study found that the therapeutic effect of atorvastatin was better than fibrates.

[Identification and Characterization of circRNAs in the Developing Stem Cambium of Poplar Seedlings]

Non-coding RNAs are a class of RNAs with multiple roles in plant life. Covalently closed circular RNA molecules (circRNAs) have been recently shown to be a group of RNA isoforms that show widespread tissue-specific expression in plants, often cooperating with the corresponding linear mRNAs to regulate gene function. However, no previous study of poplar has identified circRNAs in the cambium and determined their potential roles in the cambium or xylem development. In the present study, we sequenced RNAs in the cambium of poplar seedlings at two developmental stages, and identified and characterized 4912 circRNAs. Alternative back-splicing circularization events for 87 genes were identified among the circRNAs derived from different chromosomes. A total of 1138 circRNAs originated from 928 host genes, which were classified among the three major functional categories by GO analysis. Thirty-nine circRNAs were differentially expressed between cambium samples of stems at two developmental stages. Twenty-four DEcircRNAs interacted with 98 miRNAs as targets, of which some were associated with cambium growth and development. The results suggest that circRNAs play important roles in the cambium in relation to the regulation of stem growth and development in poplar seedlings.

Heavy metal pollution improves allelopathic effects of Canada goldenrod on lettuce germination

Large amounts of heavy metals have been released into the environment. Thus, the allelopathic effects of invasive alien species on the germination performance of co-occurring indigenous species may be altered or even heightened with the rapid growth in heavy metal pollution. This study evaluated the impacts of Canada goldenrod (Solidago canadensis L.) leaf extracts at concentrations of 0, 10 or 20 gl 1 on the germination of lettuce under different forms of heavy metal pollution (Cu2+ , Pb2+ or a combination of Cu2+ and Pb2+ ; 35 mgl 1) during incubation in Petri dishes for 10 days. Goldenrod leaf extracts (high concentration) reduced growth of aboveground and belowground parts of lettuce as well as competition for light and soil nutrients. However, low concentrations of goldenrod leaf extracts dramatically improved growth of lettuce roots, competition for light, soil nutrient availability, leaf photosynthetic area and growth competitiveness. The combination of goldenrod leaf extracts and heavy metal pollution was synergistic on most lettuce germination parameters, probably because high concentrations of goldenrod leaf extracts together with heavy metal pollution had a synergistic negative impact on lettuce germination. Consequently, increased levels of heavy metal pollution may favour invasion of invasive alien species while largely suppressing germination of indigenous species.

Activation of p38MAPK in spinal microglia contributes to autologous nucleus pulposus-induced mechanical hyperalgesia in a modified rat model of lumbar disk herniation

Recent studies have implicated the activation of p38 mitogen-activated protein kinase (MAPK) and glial cells contribute to hyperalgesia following nerve injury or nerve compression. In our work, we investigated the underlying mechanisms of autologous nucleus pulposus (NP)-induced mechanical hyperalgesia in a modified rat model of lumbar disk herniation (LDH). Firstly, our results showed that 50% mechanical withdrawal threshold (50% MWT) decreased on postoperative day (POD) 1 and significantly minimally reduced on POD 7 and lasted for day 28 after surgery (P < 0.05). Secondly, phosphorylation of p38MAPK (p-p38MAPK) and glial cells were monitored on POD 1, 3, 7, 14 and 28 using immunofluorescence staining. P38MAPK activation, observed in the spinal cord, began to increase on POD 1, peaked on POD 3, and significantly decreased on POD 14 and POD 28 (P < 0.05). Microglia activation was initiated at day 1, maximal at day 3, and maintained until day 14 after surgery (P < 0.05). Astrocytic activation was found in 7 to 14 days after modelling (P < 0.05). Then, double immunostaining method was applied to observe the co-expression of p-p38MAPK and glial cells, and it showed that p-p38MAPK was mainly expressed in activated microglia, rarely in neurons, and none in astrocytes. Lastly, we discovered that both SB203580 (50ug, p38MAPK inhibitor) and minocycline (0.5 mg, microglial inhibitor) would inhibit the p-p38MAPK protein expression tested by western blot analysis and reduce mechanical hyperalgesia. In conclusion, current study suggest that activation or phosphorylation of p38MAPK in spinal microglia contributes to autologous NP-induced mechanical hyperalgesia in our animal model.

AB1067 CASE OR FAMILY?FROM 2 CHINESE FCAS3 CHILDREN WITH PLCG2 MUTATION TO THEIR FAMILIES

Background:

Familial cold autoinflammatory syndrome 3 (FCAS3) is an autoinflammatory disease (AID) caused by mutation of the PLCG2 gene, which has not been reported in China. We will report 2 cases of Chinese FCAS3 patients with no claimed family history, but we found the same mutations in a parent during their genetic analysis. After further inquiry of the parent’s medical history, we confirmed that actually, they were two FCAS3 families. Through a literature review, we found that the clinical features of Chinese patients are milder than foreign countries, and their symptoms are concealed and may be ignored, resulting in mistakes in family history collecting.

Objectives:

To summarize the genetic and clinical features of Chinese FCAS3 patients and to provide diagnostic recommendations for the disease.

Methods:

Two suspected AID children with recurrent fever and urticaria were enrolled in this study. Clinical data and family history were collected, and genetic analysis was performed by next-generation sequencing (PID panel or WES) and Sanger-based validation. Literature was reviewed from PubMed, CNKI, and Wanfang Database.

Results:

The two children were both diagnosed to be FCAS3 with PLCG2 mutation. The clinical manifestations of 2 children were recurrent fever, urticaria, and increased ESR and CRP. Case 1 has a paternal, and Case 2 has a maternal heterozygous mutation in the PLCG2 gene, while both had claimed without a family history. Further inquiry showed the two parents used to have a fever with urticaria. By comparing with foreign literature, we found our patients were milder than abroad patients. Large fragment deletions were relatively more common in foreign patients.

Conclusion:

We reported the case of FCAS3 in China for the first time. Their genotype and phenotype were different from foreign patients. Their symptoms are mild, and heterozygous mutations are more common than foreign patients, which are the main differences. The difference in mutation type may be the reason for different clinical manifestations. Besides, both two families showed a trend of more severe clinical features in the next generation. As the symptoms of the elders were not obvious and may be ignored, it caused trouble for the genetic diagnosis. Therefore, family history should be collected carefully. For rashes and fevers, which are not too severe in overall symptoms, care should be taken about the possibility of AIDs. Genetic testing can help to make a definite diagnosis.

Table 1.

Descriptive charecteristics of the patients with FMF, n=474

VariableCompliant(n=230)Noncompliant (n=244)P valueGender of patient (F)142(61.7)147(60.2)0.73Age, years*35(28-42.5)34(27-44.2)0.88Being Married152(66.1)146(59.8)0.15Disease duration, years*22(14-31)22(15-31)0.71Number of index flare*within last 12-month6.7(1-10)5(3-10)<0.001Family historyof parents54(23.5)39(16.0)0.04Family historyof sibling73(32.9)102(43.4)0.02Comorbid disease presence73(31.7)55(22.5)0.02Treatment<0.001Colchicine230 (94.1)180(78.6)Anakinra&Canakinumab134(5.3)49(21.4)Colchicine response presence127(55.2)126(52.3)0.52Drug using except FMF74(32.2)44(18.0)<0.001Presence of 2 attacks except fever90 (39.1)68(27.9)0.009Chronic peripheral arthritis16(7.0)7(2.9)0.03Amyloidosis18(7.8)9(3.7)0.05Proteinuria23(10.8)8(3.6)0.004Adequate medical care161(70.0)132(54.8)<0.001ISSF severity score*3(2-4)3(2-4)0.02ADDI index*1(0-1)1(0-1)0.05

References:

[1]Pathak S, Mcdermott M F, Savic S. Autoinflammatory diseases: update on classification diagnosis and management[J]. Journal of Clinical Pathology, 2017, 70(1):1-8.

[2]Broderick, L., Hereditary Autoinflammatory Disorders: Recognition and Treatment. Immunol Allergy Clin North Am, 2019. 39(1):13-29.

[3]Milner, Joshua D. PLAID: A Syndrome of Complex Patterns of Disease and Unique Phenotypes[J]. Journal of Clinical Immunology, 2015, 35(6):527-530.

[4]Picard C, Gaspar H B, Al-Herz W, et al. International Union of Immunological Societies: 2017 Primary Immunodeficiency Diseases Committee Report on Inborn Errors of Immunity[J]. Journal of Clinical Immunology, 2017, 38(Suppl 1):96-128.

[5]Ombrello M J, Remmers E F, Sun G, et al. Cold Urticaria, Immunodeficiency, and Autoimmunity Related to PLCG2 Deletions[J]. New England Journal of Medicine, 2012, 366(4):330-8.

[6]Zhou Q, Lee GS, Brady J, et al. A Hypermorphic Missense Mutation in PLCG2, Encoding Phospholipase Cγ2, Causes a Dominantly Inherited Autoinflammatory Disease with Immunodeficiency[J]. American Journal of Human Genetics, 2012, 91(4).

[7]Neves, J.F., et al., Novel PLCG2 Mutation in a Patient with APLAID and Cutis Laxa. Front Immunol, 2018. 9: 2863.

[8]Mcdermott M F, Aksentijevich I, Galon J, et al. Germline mutations in the extracellular domains of the 55 kDa TNF receptor, TNFR1, define a family of dominantly inherited autoinflammatory syndromes[J]. Cell, 1999, 97(1):133-144.

Disclosure of Interests:

None declared

[Analysis of the pregnancy outcomes in pregnant women with COVID-19 in Hubei Province]

Objective: To study the effect of COVID-19 on pregnancy outcomes and neonatal prognosis in Hubei Province. Method: s A retrospective comparison of the pregnancy outcomes was done between 16 women with COVID-19 and 45 women without COVID-19. Also, the results of laboratory tests, imaging examinations, and the 2019 novel coronavirus (2019-nCoV) nucleic acid test were performed in 10 cases of neonatal delivered from women with COVID-19. Result: s (1) Of the 16 pregnant women with COVID-19, 15 cases were ordinary type and 1 case was severe type. No one has progressed to critical pneumonia.The delivery method of the two groups was cesarean section, and the gestational age were (38.7±1.4) and (37.9±1.6) weeks,there was no significant difference between the two groups (P>0.05). Also, there wee no significant differences in the intraoperative blood loss and birth weight of the newborn between the two groups (all P>0.05). (2) Ten cases of neonates delivered from pregnant women with COVID-19 were collected. The 2019-nCoV nucleic acid test were all negative.There were no significant differences in fetal distress, meconium-stained amniotic fluid, preterm birth, and neonatal asphyxia between the two groups (all P>0.05).(3) In the treatment of uterine contraction fatigue, carbetocin or carboprost tromethamine was used more in cesarean section for pregnant women with COVID-19 (1.3±0.6), compared with Non-COVID-19 group (0.5±0.7),the difference was statistically significant (P=0.001). Conclusions: If there is an indication for obstetric surgery or critical illness of COVID-19 in pregnant women, timely termination of pregnancy will not increase the risk of premature birth and asphyxia of the newborn, but it is beneficial to the treatment and rehabilitation of maternal pneumonia. Preventive use of long-acting uterotonic agents could reduce the incidence of postpartum hemorrhage during surgery. 2019-nCoV infection has not been found in neonates delivered from pregnant women with COVID-19.

Low false positive and accurate detection of yeast cell viability and concentration using an automatic staining and lensfree imaging platform

Yeast cell viability and concentration are the crucial factors affecting product quality in food industry and bio-fuel production, as well as the evaluation basis for environmental toxic compounds. To overcome the drawbacks of existing methods, including high error, false positive and low automation, we propose a highly accurate approach based on an automatic staining and high-throughput lensfree imaging platform. A precisely controlled staining process is implemented automatically, which largely avoids the error caused by inappropriate exposure times. Based on optical simulation analysis, energy distribution characteristics are proposed. They are better with steady theoretical evidence for live yeast cell recognition. The parameters are directly extracted from raw cell fingerprints without any reconstruction. Those progresses improve robustness and increase efficiency. Availability of this approach is validated by compared the detection results with gold-standard PI counting method in a H₂O₂ toxicity test. So it is expected to be widely used in industrial production and environmental toxicity assessment.