Accurate diagnosis and prognosis prediction of gastric cancer using deep learning on digital pathological images: A retrospective multicentre study

Background

To reduce the high incidence and mortality of gastric cancer (GC), we aimed to develop deep learning-based models to assist in predicting the diagnosis and overall survival (OS) of GC patients using pathological images.

Methods

2333 hematoxylin and eosin-stained pathological pictures of 1037 GC patients were collected from two cohorts to develop our algorithms, Renmin Hospital of Wuhan University (RHWU) and the Cancer Genome Atlas (TCGA). Additionally, we gained 175 digital pictures of 91 GC patients from National Human Genetic Resources Sharing Service Platform (NHGRP), served as the independent external validation set. Two models were developed using artificial intelligence (AI), one named GastroMIL for diagnosing GC, and the other named MIL-GC for predicting outcome of GC.

Findings

The discriminatory power of GastroMIL achieved accuracy 0.920 in the external validation set, superior to that of the junior pathologist and comparable to that of expert pathologists. In the prognostic model, C-indices for survival prediction of internal and external validation sets were 0.671 and 0.657, respectively. Moreover, the risk score output by MIL-GC in the external validation set was proved to be a strong predictor of OS both in the univariate (HR = 2.414, P < 0.0001) and multivariable (HR = 1.803, P = 0.043) analyses. The predicting process is available at an online website (https://baigao.github.io/Pathologic-Prognostic-Analysis/).

Interpretation

Our study developed AI models and contributed to predicting precise diagnosis and prognosis of GC patients, which will offer assistance to choose appropriate treatment to improve the survival status of GC patients.

Funding

Not applicable.

Combining Sodium Butyrate With Cisplatin Increases the Apoptosis of Gastric Cancer In Vivo and In Vitro via the Mitochondrial Apoptosis Pathway

Introduction: The gastrointestinal malignancy, gastric cancer (GC), has a high incidence worldwide. Cisplatin is a traditional chemotherapeutic drug that is generally applied to treat cancer; however, drug tolerance affects its efficacy. Sodium butyrate is an intestinal flora derivative that has general anti-cancer effects in vitro and in vivo via pro-apoptosis effects and can improve prognosis in combination with traditional chemotherapy drugs. The present study aimed to assess the effect of sodium butyrate combined with cisplatin on GC. Methods: A Cell Counting Kit-8 assay was used to assess the viability of GC cells in vitro. Hoechst 33,258 staining and Annexin V-Phycoerythrin/7-Aminoactinomycin D were used to qualitatively and quantitatively detect apoptosis in GC cells. Intracellular reactive oxygen species (ROS) measurement and a mitochondrial membrane potential (MMP) assay kit were used to qualitatively and quantitatively reflect the function of mitochondria in GC cells. Western blotting was used to verify the above experimental results. A nude mouse xenograft tumor model was used to evaluate the anti-tumor efficacity of sodium and cisplatin butyrate in vivo. Results: Cisplatin combined with sodium butyrate increased the apoptosis of GC cells. In the nude mouse xenograft tumor model, sodium butyrate in combination with cisplatin markedly inhibited the growth of the tumor more effectively than either single agent. The combination of sodium butyrate and cisplatin increased the intracellular ROS, decreased the MMP, and suppressed the invasion and migration abilities of GC cells. Western blotting verified that the combination of sodium butyrate and cisplatin remarkably enhanced the levels of mitochondrial apoptosis-related pathway proteins. Conclusion: Sodium butyrate, a histone acetylation inhibitor produced by intestinal flora fermentation, combined with cisplatin enhanced the apoptosis of GC cells through the mitochondrial apoptosis-related pathway, which might be considered as a therapeutic option for GC.

[Analysis of spirometer data of 5272 coal dust-exposed miners]

Objective: To analyze the spirometer data of coal mine workers, explore the impact of coal dust on the lung function of coal mine workers. Methods: From June to December 2018, 5272 male coal mine dust-exposed workers who underwent occupational health examinations at the Xinjiang Uygur Autonomous Region Occupational Disease Prevention and Treatment Hospital were selected as the research subjects. The basic information and spirometer data of the workers were collected and analyzed for different ages, years of service and the degree of lung function injury of workers exposed to dust and its influencing factors. Results: The total detection rate of lung function injury among dust-exposed workers was 33.9% (1785/5272) . The type of injury was mainly restrictive ventilatory dysfunction (66.7%, 1190/1785) , followed by mixed ventilatory dysfunction (31.4%, 561/1785) , obstructive ventilatory dysfunction (1.9%, 34/1785) . The detection rate of mild lung function impairment was 21.0% (1105/5272) , The detected rate of moderate or higher lung injury was 12.9% (680/5272) . The abnormal detection rate of chest radiography was 3.4% (179/5272) . The logistic regression analysis of the factors affecting lung function damage showed that employees aged 40-<50 were more likely to detect overall lung function injury and the moderate or higher lung injury (P<0.05) , and that they had been working for 35 to 45 years and excavators were more likely to detect overall function injury and different degree of lung injury (P<0.05) . Conclusion: The lung function injury of coal mine dust-exposed workers is related to their age, dust-exposed working years and type of work, mainly with mild injury and restrictive ventilation dysfunction.

P–165 Using Artificial Intelligence to Classify Embryo Shape: An International Perspective

Study question

Is a pre-trained machine learning algorithm able to accurately detect cellular arrangement in 4-cell embryos from a different continent?

Summary answer

Artificial Intelligence (AI) analysis of 4-cell embryo classification is transferable across clinics globally with 79% accuracy.

What is known already

Previous studies observing four-cell human embryo configurations have demonstrated that non-tetrahedral embryos (embryos in which cells make contact with fewer than 3 other cells) are associated with compromised blastulation and implantation potential. Previous research by this study group has indicated the efficacy of AI models in classification of tetrahedral and non-tetrahedral embryos with 87% accuracy, with a database comprising 2 clinics both from the same country (Brazil). This study aims to evaluate the transferability and robustness of this model on blind test data from a different country (France).

Study design, size, duration

The study was a retrospective cohort analysis in which 909 4-cell embryo images (“tetrahedral”, n = 749; “non-tetrahedral”, n = 160) were collected from 3 clinics (2 Brazilian, 1 French). All embryos were captured at the central focal plane using Embryoscope™ time-lapse incubators. The training data consisted solely of embryo images captured in Brazil (586 tetrahedral; 87 non-tetrahedral) and the test data consisted exclusively of embryo images captured in France (163 tetrahedral; 72 non-tetrahedral).

Participants/materials, setting, methods

The embryo images were labelled as either “tetrahedral” or “non-tetrahedral” at their respective clinics. Annotations were then validated by three operators. A ResNet–50 neural network model pretrained on ImageNet was fine-tuned on the training dataset to predict the correct annotation for each image. We used the cross entropy loss function and the RMSprop optimiser (lr = 1e–5). Simple data augmentations (flips and rotations) were used during the training process to help counteract class imbalances.

Main results and the role of chance

Our model was capable of classifying embryos in the blind French test set with 79% accuracy when trained with the Brazilian data. The model had sensitivity of 91% and 51% for tetrahedral and non-tetrahedral embryos respectively; precision was 81% and 73%; F1 score was 86% and 60%; and AUC was 0.61 and 0.64. This represents a 10% decrease in accuracy compared to when the model both trained and tested on different data from the same clinics.

Limitations, reasons for caution

Although strict inclusion and exclusion criteria were used, inter-operator variability may affect the pre-processing stage of the algorithm. Moreover, as only one focal plane was used, ambiguous cases were interpoloated and further annotated. Analysing embryos at multiple focal planes may prove crucial in improving the accuracy of the model.

Wider implications of the findings: Though the use of machine learning models in the analysis of embryo imagery has grown in recent years, there has been concern over their robustness and transferability. While previous results have demonstrated the utility of locally-trained models, our results highlight the potential for models to be implemented across different clinics.

Trial registration number

Not applicable

[Viral pathogenic spectrum analysis of severe acute respiratory infection cases in Luohe City, Henan province from 2017 to 2019]

Objective: The purpose of this study was to investigate the characteristics of viral pathogen spectrum and the epidemiological characteristics of each viral pathogen in hospitalized cases associated with severe acute respiratory infection (SARI) in Luohe City, Henan Province from 2017 to 2019. Methods: Based the SARI Case Surveillance Platform, SARI cases were collected in Central Hospital of Luohe City, Henan Province from November 2017 to February 2019. In the end, 783 SARI cases were included, whose throat swabs were taken within 24 h of admission, as well as their demographic characteristics, onset time, clinical characteristics and other information recorded. At the same time, viral identification was performed, and the age and time distribution of each virus were analyzed. Results: The age of 783 SARI cases shown as M (P₂₅, P₇₅) was 3 (1, 5) years old, ranging from 1 month to 95 years old. Children under 5 years old were the majority (71.01%). The males (61.81%) were more than females (38.18%). Among the 783 SARI cases, a total of 9 kind of viruses were identified with 64.88% (508/783) of the throat swabs tested positive for at least one virus. The positive rate of influenza virus and human respiratory syncytial virus were both 20.18% (158 cases), which was the highest among all the detected respiratory virus. The co-infection rate was 15.84% (124/783), among which double infection was the most common, accounting for 85.48% (106/124) of the co-infected cases. And human respiratory syncytial virus, human rhinovirus and influenza virus were the most common pathogen in co-infection cases. Moreover, the viral positive rate was 68.71% in children aged 5 years and 63.27% in people aged 60-95 years. Influenza and human respiratory syncytial virus dominated in winter and spring, while human parainfluenza virus was the main infection in summer. Conclusion: Influenza virus and human respiratory syncytial virus were the main viruses in throat swabs of SARI cases from 2017 to 2019 in Luohe City, Henan Province. There were differences in the age and seasonal epidemiological characteristics of each virus.

P–280 Changes in oolemma height during ICSI injection on day 0 is associated with day 5–6 blastocyst formation

Study question

Does the oolemma response to ICSI injection on day 0 affect blastocyst formation on day 5–6 (d5/6)?

Summary answer

A large change in oolemma height during ICSI injection on day 0 is associated with lower blastocyst formation rates on d5/6.

What is known already

The oolemma changes in all dimensions (i.e. height, width and depth) and can exhibit different reactions in ICSI during needle injection. This is seen as instant rupture or with little needle pressure, normal rupture with the needle pushed approximately halfway through, or difficult rupture with repeated attempts or the needle passing 3/4 of the oocyte width. Previous studies have shown that these responses can affect degeneration and fertilisation rates on day 1, however, there is little research on its effect on blastocyst formation rates. Furthermore, most previous studies have used qualitative methods to assess oolemma response.

Study design, size, duration

This is a retrospective study using ICSI procedure videos conducted by four embryologists in a private clinic from 2013–2015. All videos of procedures which did not result in 2PN or in which the oocyte was not fully visible were excluded. Six operators categorised 455 videos (by majority vote) into four groups based on the oolemma response: oolemma breakage within 1/4, between 1/4 and 1/2, between 1/2 and 3/4 and beyond 3/4 of the oocyte’s width.

Participants/materials, setting, methods

A U-Net neural network model was trained to extract the frame of maximum oolemma indent from each video which were validated by a human operator; any in which maximum indent occured after breaking of the oolemma were excluded. The ratio of starting to maximal indent width/height were calculated automatically and human-validated. Chi-squared tests were performed for each ratio vs d5/6 blastocyst formation. These results were compared with those obtained from purely human annotations.

Main results and the role of chance

From the purely human annotations, the percentages of oocytes in groups 1–4 respectively were: 3.3%, 85.3%, 11.4% and 0%. This variation in oolemma response may be due to the arrangement of thick and thin microfilaments or cortical granules in the cytoskeleton. When analysed with d5/6 blastocyst formation, these showed no significant result (p = 0.12) which is consistent with findings using the model.

The artificial intelligence (AI) model processed 26 frames per second. During human validation of the ratios calculated at maximal indentation, 36% of width ratios and 31% of height ratios were rejected.

The proportion of blastocysts formed in the upper and lower quartile for each ratio was analysed. Both the upper (0.49) and lower (0.41) quartiles of the width ratios were not significant for d5/6 blastocyst formation. The lower (1.12) quartile of height ratios showed no significance, however there were significantly fewer blastocysts formed on d5/6 for the upper (1.18) quartile of height ratios (p &lt; 0.025). This subtle change in the height ratio, which was significant for d5/6 blastocyst formation was not taken into account when grouping oocytes any previous literature (and our human labelling).

Limitations, reasons for caution

This study was conducted at a single clinic so variations between clinics were not captured in the study and would need further collaborations to confirm the proportion of oocytes responses. Due to the small sample size, this study also did not identify any group 4 oocytes cultured until d5/6.

Wider implications of the findings: The grouping criteria in this study were more quantitative than previous work yet indicated no correlation between the oolemma group and d5/6 blastocyst formation. However, changes in the height which are hard to assess in real-time (and which have been neglected in previous literature) were seen to be significant.

Trial registration number

NA

TRIM11 Promotes Proliferation, Migration, Invasion and EMT of Gastric Cancer by Activating β-Catenin Signaling

Introduction

Gastric cancer (GC) is the sixth most common malignant tumor and the third leading cause of cancer-related death in the world. Studies have shown that TRIM protein can regulate transcription factor activity and is associated with many cancers. However, the role of TRIM11 in gastric cancer remains unclear.

Methods

TRIM11 protein levels were examined in 36 cases of GC tissues and 4 gastric cancer cell lines. TRIM11 overexpression and knockdown cells were constructed in MGC-803, HGC-27 and SGC-7901, respectively. The biological roles and mechanisms of TRIM11 were examined using CCK8, colony formation, transwell migration assay, invasion assay, Western blotting, Immunohistochemistry and in vivo nude mice experiments.

Results

We found that TRIM11 was upregulated in gastric cancer tissues and gastric cancer cell lines. Functionally, TRIM11 overexpression increased growth rate, colony formation, invasion and migration ability, EMT and β-catenin protein level and its downstream proteins such as CyclinD1 and C-myc, while TRIM11 knockdown shows the opposite effects.

Conclusion

In summary, our data show that TRIM11 is overexpressed in GC. TRIM11 promotes proliferation, migration, invasion and EMT of gastric cancer by activating β-catenin signaling.

Planktonic and sediment bacterial communities in an integrated mariculture system

An integrated multi-trophic aquaculture (IMTA) system, with one fish cage model surrounded by an island and shellfish rafts, was used in the current study. Planktonic and sediment bacterial communities in the IMTA system were monitored over four seasons in 2019. In both plankton and sediment samples, the most dominant phyla were Proteobacteria and Bacteroidota. Sediment bacterial samples were more similar and had higher levels of biodiversity than planktonic bacterial samples. Obvious seasonal variations were found in plankton samples, but not in sediment samples. No obvious inter-site variations in planktonic and sediment bacteria (fish cages, shellfish rafts and control sites) were found and the results suggested that no obvious impact of feeding operations in fish culture cage model on bacterial communities in the IMTA system was observed in this study. Based on the sequence data, some faecal indicator bacteria and potentially pathogenic bacterial species were detected. According to the results, the bacterial water quality in the IMTA system was acceptable. PICRUSt (Phylogenetic Investigation of Communities by Reconstruction of Unobserved States) analysis revealed that the primary difference in potential functional roles of planktonic and sediment bacteria was amino acid transport and metabolism, which was active in different seasons.

The effect of in-hospital high-dose vs. low-dose intensive statin in patients with non-ST segment elevation acute coronary syndrome

Background

Statins remain a standard treatment for acute coronary syndrome (ACS) patients. We aimed to determine the association between different dosages of in-hospital statins and the prognoses among patients receiving percutaneous coronary intervention (PCI).

Methods

NSTE-ACS patients were retrospectively enrolled from January 2010 to December 2014 from five centres in China. Patients receiving either atorvastatin or rosuvastatin during their hospitalizations were included. All the patients were categorized into high-dose statin group (40mg atorvastatin or 20mg rosuvastatin) or low-dose statin group (20mg atorvastatin or 10mg rosuvastatin). In-hospital events and long-term all-cause death was recorded.

Results

Of the 7,008 patients included in the study, 5,248 received low-dose intensive statin (mean age: 64.28±10.39; female: 25.2%), and 1,760 received high-dose intensive statin (mean age: 63.68±10.59; female: 23.1%). There was no significant difference in in-hospital all-cause death between the two groups (adjusted OR, 1.27; P=0.665). All-cause death was similar between the two groups during the long-term follow-up period (30-day: adjusted HR, 1.28; P=0.571; 3-year: adjusted HR, 0.83; P=0.082). However, there was a robust association between the high-dose statin and the reduction in in-hospital dialysis (adjusted OR, 0.11; P=0.030).

Conclusions

The in-hospital high-dose intensive statin is not associated with lower risks of in-hospital or follow-up all-cause death in NSTE-ACS patients undergoing PCI. Considering the robust beneficial effect of in-hospital dialysis, an individualized high-dose intensive statin can be rational in specified populations.

Univariate and multivariate analyses

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): The Science and Technology Planning Project of Guangzhou City athe China Youth Research Funding

Novel long non-coding RNA LBX2-AS1 indicates poor prognosis and promotes cell proliferation and metastasis through Notch signaling in non-small cell lung cancer

OBJECTIVE

Recent reports have suggested that long non-coding RNA LBX2 antisense RNA 1 (LBX2-AS1) acts as an important regulator in cancer progression. This study aimed to investigate the clinical significance of LBX2-AS1 in non-small cell lung cancer (NSCLC) patients and its biological functions.

PATIENTS AND METHODS

The expressions of LBX2-AS1 were examined in 165 paired NSCLC tissues and adjacent normal tissues from NSCLC patients by qRT-PCR. The clinical significance of LBX2-AS1 was determined using a series of statistical methods. The effects of LBX2-AS1 knockdown on NSCLC cell proliferation, migration, and invasion were investigated by CCK-8 assays, colony formation assays, EdU proliferation assays, Wound healing assays, and transwell assays. The promotive roles of LBX2-AS1 on Notch1 signal were determined using RT-PCR and Western blot.

RESULTS

We found that LBX2-AS1 was highly expressed in NSCLC tissues and cell lines. The increased levels of LBX2-AS1 were observed to be positively correlated with TNM stage, histological grade, and lymph node metastasis. Furthermore, the Kaplan-Meier survival curves indicated that patients with higher expressions of LBX2-AS1 had unfavorable overall survival. Lost-of-functions assays revealed that the knockdown of LBX2-AS1 in H1299 and A549 cells inhibited cell proliferation, migration, and invasion. Mechanistic studies revealed that the suppression of LBX2-AS1 resulted in the reduced expressions of Notch1, p21, and Hes1, suggesting that LBX2-AS1 might promote the activation of the Notch pathway.

CONCLUSIONS

Our study identified a novel NSCLC-related lncRNA LBX2-AS1, which may represent a novel prognostic biomarker and a potential therapeutic target for NSCLC.

Thymoquinone inhibits the proliferation and invasion of esophageal cancer cells by disrupting the AKT/GSK-3β/Wnt signaling pathway via PTEN upregulation

Although thymoquinone (TQ) has been reported to exert antitumor activity against various types of human cancers without evident toxicity, limited studies have reported the effects of TQ on esophageal cancer. Here, we showed that TQ induced cell cycle arrest in the G2/M phase and significantly inhibited cell proliferation and invasion. Further investigation of the potential mechanism revealed that TQ increased the levels of p53 and p21 but significantly reduced the expression of Cyclin B1, Cyclin A, and Cyclin E. Moreover, TQ led to a decrease in Bcl-2 and an increase in cleaved caspase-3, cleaved caspase-7, cleaved caspase-9, and Bax, indicating that TQ induced apoptosis by activating the intrinsic mitochondrial apoptosis pathway. Western blotting showed that TQ disrupted the PI3K/AKT pathway by upregulating PTEN, thus modulating GSK-3β activity, increasing β-catenin degradation, and decreasing decreased MMP-2 and MMP-9 levels in Eca109 cells. However, these changes were attenuated by disrupting PTEN function (using a potent inhibitor) or downregulating PTEN expression. In addition, in vivo results showed that the efficacy of TQ as an antitumor agent in a mouse xenograft tumor model. In conclusion, TQ suppressed human esophageal cancer cells proliferation and invasion both in vitro and in vivo and could provide a novel therapeutic approach for esophageal cancer.

Hesperetin Promotes Cisplatin-Induced Apoptosis of Gastric Cancer In Vitro and In Vivo by Upregulating PTEN Expression

As one of the most common malignant gastrointestinal tumors, gastric cancer (GC) has a high incidence and poor prognosis. Cisplatin (DDP) is often used as chemotherapy for advanced GC; however, the high incidence of drug resistance remains a problem. The use of several anti-tumor drugs as combined chemotherapy is an effective strategy. Hesperetin has anti-tumor ability via its pro-apoptotic effect on various human cancers, both in vitro and in vivo, with no significant toxicity. However, a combination of DDP and hesperetin in GC has not been reported. The present study aimed to investigate the in vitro and in vivo chemosensitization effect and mechanism of hesperetin-augmented DDP-induced apoptosis of GC. The proliferation of GC ty -60cells was inhibited significantly in a time and dose-dependent manner by combined treatment of DDP with hesperetin. Hesperetin markedly increased DDP-induced apoptosis of GC cell lines. In a xenograft tumor mouse model, markedly better tumor suppression was observed after treatment with DDP plus hesperetin compared with that of either agent alone. Additionally, the combination of DDP and hesperetin remarkably increased the expression levels of phosphatase and tensin homolog (PTEN) and Cytochrome C (Cyt C), and significantly decreased the levels of phosphorylated protein kinase B (p-AKT) and CyclinD1. DDP and hesperetin also induced significant increases in apoptosis inducing factor (AIF), BCL2 associated X, apoptosis regulator (BAX), cleaved caspase-9, and cleaved caspase-3, and decreased B-cell lymphoma 2 (BCL2), caspase-9, and caspase-3 levels. Thus, we demonstrated that hesperetin could inhibit the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/AKT signaling pathway and induce the mitochondrial pathway via upregulating PTEN expression, thereby significantly enhancing DDP’s anti-tumor effect on GC. Hesperetin is a potential chemotherapeutic agent for GC and merits further clinical investigation.

[Clinical characteristics of 30 medical workers infected with new coronavirus pneumonia]

Objective: To investigate the clinical characteristics of medical staff with novel coronavirus pneumonia(NCP). Methods: 30 patients infected with novel coronavirus referred to jianghan university hospital between January 11, 2020 and January 3, 2020 were studied. The data reviewed included those of clinical manifestations, laboratory investigation and Radiographic features. Results: The patients consisted of 10 men and 20 women, including 22 doctors and 8 nurses,aged 21~59 years(mean 35±8 years).They were divided to 26 common type and 4 severe cases, all of whom had close(within 1m) contact with patients infected of novel coronavirus pneumonia. The average contact times were 12 (7,16) and the average cumulative contact time was 2 (1.5,2.7) h.Clinical symptoms of these patients were fever in 23 patients (76.67%) , headache in 16 petients (53.33%) , fatigue or myalgia in 21patients (70%) , nausea, vomiting or diarrhea in 9 petients (30%) , cough in 25 petients (83.33%) , and dyspnea in 14 petients (46.67%) .Routine blood test revealed WBC<4.0×10(9)/L in 8 petients (26.67%) , (4-10) ×10(9)/L in 22 petients (73.33%) , and WBC>4.0×10(9)/L in 4 petients (13.33%) during the disease.Lymphocyte count<1.0×10(9)/L occurred in 12 petients (40%),abnormal liver function in 7 petients (23.33%) ,myocardial damage in 5 petients(16.67%), elevated D-dimer (>0.5mg/l) in 5 patients (16.67%). Compared with normal patients, the average exposure times, cumulative exposure time, BMI, Fever time, white blood cell count, liver enzyme, LDH, myoenzyme and D-dimer were significantly increased in severe patients, while the lymphocyte count and albumin levels in peripheral blood were significantly decreased.Chest CT mainly showed patchy shadows and interstitial changes.According to imaging examination, 11 patients (36.67%) showed Unilateral pneumonia and 19 patients (63.33%) showed bilateral pneumonia,4 patients (13.33%) showed bilateral multiple mottling and ground-glass opacity.Compared with the patients infected in the protected period, the proportion of severe infection and bilateral pneumonia were both increased in the patients infected in unprotected period. Conclusion: Medical staffs are at higher risk of infection.Infection rates are associated with contact time, the amount of suction virus. Severe patients had BMI increased, heating time prolonged, white blood cell count, lymphocyte count, D-dimer and albumin level significantly changed and were prone to be complicated with liver damage and myocardial damage.Strict protection measures is important to prevent infection for medical workers.

Linking vein properties to leaf biomechanics across 58 woody species from a subtropical forest

Leaf venations have elements with relatively lower elasticity than other leaf tissue components, which are thought to contribute to leaf biomechanics. A better mechanistic understanding of relationships between vein traits and leaf mechanical properties is essential for ecologically relevant interpretation of leaf structural variations. We investigated 13 major (first to third order) and minor (>third order) vein traits, six leaf mechanical properties and other structural traits across 58 woody species from a subtropical forest to elucidate how vein traits contribute to leaf biomechanics. Across species, vein dry mass density (ρ_v ), total vein dry mass per leaf area (VMA) and minor vein diameter (VD_min ), but not the lower-order vein density (VLA_1•2 ), were positively correlated with leaf force to punch (F_p ) and force to tear (F_t ). Structural equation models showed that ρ_v and VD_min not only contribute to leaf mechanical properties directly (direct pathway), but also had impacts on leaf biomechanics by influencing leaf thickness and leaf dry mass per area (indirect pathway). Our study demonstrated that vein dry mass density and minor vein diameter are the key vein properties for leaf biomechanics. We also suggest that the mechanical characteristics of venations are potential factors influencing leaf mechanical resistance, structure and leaf economics spectrum.

[Clinical characteristics of 30 medical workers infected with new coronavirus pneumonia]

Objective: To investigate the clinical characteristics of medical staff with novel coronavirus pneumonia(NCP). Methods: 30 patients infected with novel coronavirus referred to jianghan university hospital between January 11, 2020 and January 3, 2020 were studied. The data reviewed included those of clinical manifestations, laboratory investigation and Radiographic features. Results: The patients consisted of 10 men and 20 women, including 22 doctors and 8 nurses,aged 21~59 years(mean 35±8 years).They were divided to 26 common type and 4 severe cases, all of whom had close(within 1m) contact with patients infected of novel coronavirus pneumonia. The average contact times were 12 (7,16) and the average cumulative contact time was 2 (1.5,2.7) h.Clinical symptoms of these patients were fever in 23 patients (76.67%) , headache in 16 petients (53.33%) , fatigue or myalgia in 21patients (70%) , nausea, vomiting or diarrhea in 9 petients (30%) , cough in 25 petients (83.33%) , and dyspnea in 14 petients (46.67%) .Routine blood test revealed WBC <4.0×10(9)/L in 8 petients (26.67%) , (4-10) ×10(9)/L in 22 petients (73.33%) , and WBC>4.0×10(9)/L in 4 petients (13.33%) during the disease.Lymphocyte count <1.0×10(9)/L occurred in 12 petients (40%),abnormal liver function in 7 petients (23.33%) ,myocardial damage in 5 petients(16.67%), elevated D-dimer (>0.5mg/l) in 5 patients (16.67%). Compared with normal patients, the average exposure times, cumulative exposure time, BMI, Fever time, white blood cell count, liver enzyme, LDH, myoenzyme and D-dimer were significantly increased in severe patients, while the lymphocyte count and albumin levels in peripheral blood were significantly decreased.Chest CT mainly showed patchy shadows and interstitial changes.According to imaging examination, 11 patients (36.67%) showed Unilateral pneumonia and 19 patients (63.33%) showed bilateral pneumonia,4 patients (13.33%) showed bilateral multiple mottling and ground-glass opacity.Compared with the patients infected in the protected period, the proportion of severe infection and bilateral pneumonia were both increased in the patients infected in unprotected period. Conclusion: Medical staffs are at higher risk of infection.Infection rates are associated with contact time, the amount of suction virus. Severe patients had BMI increased, heating time prolonged , white blood cell count, lymphocyte count, D-dimer and albumin level significantly changed and were prone to be complicated with liver damage and myocardial damage.Strict protection measures is important to prevent infection for medical workers.