[Key microbial monitoring and clinical analysis of bloodstream infections and CRO colonization after hematopoietic stem cell transplantation in hematological patients]

Objective: To investigate the distribution and clinical characteristics of pathogenic bacteria following hematopoietic stem cell transplantation (HSCT), as well as to provide a preliminary research foundation for key microbial monitoring, and clinical diagnosis and treatment of infections after HSCT in hematological patients. Methods: We retrospectively analyzed the clinical data of 190 patients who tested positive for microbial testing [G-bacteria blood culture and/or carbapenem-resistant organism (CRO) screening of perianal swabs] at our center from January 2018 to December 2022. Patients were divided into blood culture positive, perianal swab positive, and double positive groups based on the testing results. The three patient groups underwent statistical analysis and comparison. Results: The top four pathogenic bacteria isolated from sixty-three patients with G-bacteria bloodstream infection (BSI) were Escherichia coli (28 strains, 43.75% ), Klebsiella pneumonia (26 strains, 40.63% ), Pseudomonas aeruginosa (3 strains, 4.69% ), and Enterobacter cloacae (3 strains, 4.69% ). The top three pathogenic bacteria isolated from 147 patients with CRO perianal colonization were carbapenem-resistant Klebsiella pneumoniae (58 strains, 32.58% ), carbapenem-resistant Escherichia coli (49 strains, 27.53% ), and carbapenem-resistant Enterobacter cloacae (20 strains, 11.24% ). The 3-year disease-free survival (DFS ) and overall survival (OS) of double positive group patients were significantly lower compared to those in the blood culture and perianal swab positive groups (DFS: 35.6% vs 53.7% vs 68.6%, P=0.001; OS: 44.4% vs 62.4% vs 76.9%, P<0.001), while non-relapse mortality (NRM) was significantly higher (50.0% vs 34.9% vs 10.6%, P<0.001). Failed engraftment of platelets and BSI are independent risk factors for NRM (P<0.001). Using polymyxin and/or ceftazidime-avibactam for more than 7 days is an independent protective factor for NRM (P=0.035) . Conclusion: This study suggests that the occurrence of BSI significantly increases the NRM after HSCT in patients with hematological diseases; CRO colonization into the bloodstream has a significant impact on the DFS and OS of HSCT patients.

Epitope delimitation: A new method for defining epitopes of human IgG-reactive antigenic peptides based on rabbit-recognized epitope motifs

The use of precise epitope peptides as antigens is essential for accurate serological diagnosis of viral-infected individuals, but now it remains an unsolvable problem for mapping precise B cell epitopes (BCEs) recognized by human serum. To address this challenge, we propose a novel epitope delimitation (ED) method to uncover BCEs in the delineated human IgG-reactive (HR) antigenic peptides (APs). Specifically, the method based on the rationale of similarities in humoral immune responses between mammalian species consists of a pair of elements: experimentally delineated HR-AP and rabbit-recognized (RR) BCE motif and corresponding pair of sequence alignment analysis. As a result of using the ED approach, after decoding four RR-epitomes of human papillomavirus types 16/18-E6 and E7 proteins utilizing rabbit serum against each recombinant protein and sequence alignment analysis of HR-APs and RR-BCEs, 19 fine BCEs in 17 of 22 known HR-APs were defined based on each corresponding RR-BCE motifs, including the type-specificity of each delimited BCE in homologous proteins. The test with 22 known 16/20mer HR-APs demonstrated that the ED method is effective and efficient, indicating that it can be used as an alternative method to the conventional identification of fine BCEs using overlapping 8mer peptides.

Allergic diseases aggravate the symptoms of SARS-CoV-2 infection in China

Background

The relationship between allergic diseases and the adverse outcomes of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been a subject of controversy. This study aimed to investigate the association between allergic diseases and the incidence and severity of symptoms in SARS-CoV-2 infection.

Methods

Clinical data of individuals, including children and their parents, infected with SARS-CoV-2 from December 2022 to January 2023 in China were retrospectively analyzed. The data were collected through questionnaires. Statistical analysis, including chi-squared tests, nonparametric analysis, one-way ANOVA, and logistic regression analysis, was used to examine the relationship between allergic diseases, prior medication, and the symptoms of SARS-CoV-2 infection.

Results

There were 3,517 adults and 3,372 children with SARS-CoV-2 infection included in the study. Fever was found to occur at similar rates in children (86.5%) and adults (86.8%). However, other symptoms related to respiratory issues (such as cough and sore throat), neurological symptoms (headache, loss of smell, and loss of taste), and systemic symptoms (muscle soreness and weakness) were observed more frequently in adults (P < 0.001). Additionally, adults exhibited higher overall symptom scores, indicating greater severity. Allergic diseases were found to be associated with the incidence of certain SARS-CoV-2 infection symptoms in both children and adults. Specifically, children with allergic rhinitis (AR) were observed to be more susceptible to upper respiratory symptoms (OR: 1.320, 95% CI: 1.081-1.611, P = 0.006), while asthma patients were found to be more susceptible to severe respiratory symptoms (OR: 1.736, 95% CI: 1.250-2.411, P = 0.001). Similar patterns were identified in adults. Furthermore, AR was also suggested to be a risk factor for symptom severity in both children (OR: 1.704, 95% CI: 1.314-2.209, P < 0.001) and adults (OR: 1.736, 95% CI: 1.250-2.411, P = 0.001). However, prior medication for allergic diseases did not exhibit a preventive effect on SARS-CoV-2 infection symptoms.

Conclusions

Both children and adults with allergic diseases were found to be more prone to experiencing symptoms of SARS-CoV-2 infection, and these symptoms tended to be more severe.

Rapid Prediction of Adulteration Content in Atractylodis rhizoma Based on Data and Image Features Fusions from Near-Infrared Spectroscopy and Hyperspectral Imaging Techniques

Atractylodis rhizoma (AR) is an herb and food source with great economic, medicinal, and ecological value. Atractylodes chinensis (DC.) Koidz. (AC) and Atractylodes lancea (Thunb.) DC. (AL) are its two botanical sources. The commercial fraud of AR adulterated with Atractylodes japonica Koidz. ex Kitam (AJ) frequently occurs in pursuit of higher profit. To quickly determine the content of adulteration in AC and AL powder, two spectroscopic techniques, near-infrared spectroscopy (NIRS) and hyperspectral imaging (HSI), were introduced. The partial least squares regression (PLSR) algorithm was selected for predictive modeling of AR adulteration levels. Preprocessing and feature variable extraction were used to optimize the prediction model. Then data and image feature fusions were developed to obtain the best predictive model. The results showed that if only single-spectral techniques were considered, NIRS was more suitable for both tasks than HSI techniques. In addition, by comparing the models built after the data fusion of NIRS and HSI with those built by the single spectrum, we found that the mid-level fusion strategy obtained the best models in both tasks. On this basis, combined with the color-texture features, the prediction ability of the model was further optimized. Among them, for the adulteration level prediction task of AC, the best strategy was combining MLF data (at CARS level) and color-texture features (C-TF), at which time the R2T, RMSET, R2P, and RMSEP were 99.85%, 1.25%, 98.61%, and 5.06%, respectively. For AL, the best approach was combining MLF data (at SPA level) and C-TF, with the highest R2T (99.92%) and R2P (99.00%), as well as the lowest RMSET (1.16%) and RMSEP (2.16%). Therefore, combining data and image features from NIRS and HSI is a potential strategy to predict the adulteration content quickly, non-destructively, and accurately.

Acute myocardial infarction and myocarditis following COVID-19 vaccination

Emerging reports raise concerns on the potential association between the COVID-19 vaccines and cardiac manifestations. We sought to evaluate cardiac complications associated with COVID-19 vaccination in a pooled analysis from our institution's cohort study and systematic review. Consecutive patients admitted to a tertiary hospital in Singapore between 1 January 2021 and 31 March 2021, with the onset of cardiac manifestations within 14 days following COVID-19 vaccination, were studied. Furthermore, a systematic review was performed, with PubMed, Embase, Research Square, MedRxiv and LitCovid databases accessed from inception up to 29 June 2021. Relevant manuscripts reporting individual patient data on cardiac complications following COVID-19 vaccination were included. Thirty patients were included in the study cohort, with 29 diagnosed with acute myocardial infarction (AMI) and 1 with myocarditis. Five patients developed heart failure, two had cardiogenic shock, three intubated, and one had cardiovascular-related mortality. In the systematic review, 16 studies were included with 41 myocarditis and 6 AMI cases. In the pooled analysis of the study cohort and the systematic review, 35 patients had AMI and 42 had myocarditis. Majority were men, and myocarditis patients were younger than AMI patients. Myocarditis patients tended to present 72 h postvaccination, while AMI patients were older and typically presented 24 h postvaccination. Majority with AMI or myocarditis developed symptoms after the first and second vaccination dose, respectively. This pooled analysis of patients presenting with cardiac manifestations following COVID-19 vaccination highlights the differences between myocarditis and AMI presentations in temporal association with the vaccination.

Bamboo leaf: A review of traditional medicinal property, phytochemistry, pharmacology, and purification technology

ETHNOPHARMACOLOGICAL RELEVANCE

Bamboos are perennial evergreen plants that belong to the subfamily Bambusoideae of the true grass family Poaceae, with more than thousands of species distributed around the world. They are used as a traditional medicine with demonstrated effects of anti-oxidation, free radical scavenging, anti-inflammatory, liver protection and ameliorating cognitive deficits. Bamboo leaf is mainly used for the treatment of atherosclerotic, diabetic and nervous system diseases.

AIM OF THE STUDY

This review aims to provide up-to-date information on the traditional medicinal properties, phytochemistry, pharmacology, and purification technologies of bamboo leaf.

MATERIALS AND METHODS

Relevant information on bamboo leaf was obtained by an online search of worldwide accepted scientific databases (Web of Science, ScienceDirect, Elsevier, SpringerLink, ACS Publications, Wiley Online Library and CNKI).

RESULTS

More than 100 chemical compounds, including flavonoids and flavonoid glycosides, volatile components, phenolic acids, polysaccharide, coenzyme Q10, phenylpropanoid and amino acids have been reported to be present. These compounds were usually extracted by column chromatography and membrane separation technologies. Preparative high performance liquid chromatography (PHPLC), high-speed counter-current chromatography (HSCCC), simulated moving bed chromatography (SMB) and dynamic axial compression chromatography (DAC) were the advanced separation technologies have been used to isolate C-glycosides from bamboo leaf flavonoid, the main bioactive ingredient of bamboo leaf. Currently, bamboo leaf is mainly used for the treatment of atherosclerotic, diabetic, hepatic diseases and nervous system related symptoms, which are attributed to the presence of bioactive components of bamboo leaf.

CONCLUSIONS

Phytochemical and pharmacological analyses of bamboo leaf have been revealed in recent studies. However, most of the pharmacological studies on bamboo leaf have focused on bamboo leaf flavonoids. Further studies need to pay more attention to other phytochemical components of bamboo leaf. In addition, there is lack of sufficient clinical data and toxicity studies on bamboo leaf. Therefore, more clinical and toxicity researches on this plant and constituents are recommended.

Abstract 5269: RF-1302, a novel dual inhibitor of PIM1 and FLT3 in preclinical treatment of acute myeloid leukemia

It was reported that PIM (Proviral Insertion site in Moloney murine leukemia virus) proteins are family kinases (PIM1, PIM2, and PIM3), which are upregulated in several cancer types, especially PIM1 is highly expressed in hematopoietic malignancies. PIM kinase family are responsible for enhancement of cell cycle, inhibition of apoptosis, activation of transcription, and cell homing/migration. Fms-like tyrosine kinase 3 (FLT3) is part of a family of receptor tyrosine kinases (RTKs), and a molecular therapeutic target of acute myeloid leukemia (AML). There are three FTL3 inhibitors, midostaurin, gilteritinib, and quizartinib have been approved for clinical treatment of AML. We have developed a novel dual inhibitor of PIM1 and FLT3, RF-1302 and evaluated its inhibition of cell proliferation in vitro and antitumor activity in vivo. RF1302 was found to have a strong inhibitory activity against target enzymes (PIM1 IC50 at 1.0-2.3 nM and FLT3 IC50 at 0.8-2.2 nM), which were more potent than the tested positive control drugs gilteritinib, quizartinib, and midostaurin. RF-1302 showed to be highly cytotoxic to cultured human acute myeloid leukemia (AML) cells (MV4-11 and Molm-13) with IC50 at 5.7nM and 9.5 nM, respectively. The in vivo antitumor activity of RF-1302 was evaluated and compared with midostaurin and gilteritinib in the treatment of the two AML xenograft models. RF-1302 at 20 mg/kg/daily x 14, oral) significantly delayed tumor growth and resulted in a tumor growth inhibition (TGI) of 95% (p&lt;0.001 compared with the control group) in the Molm-13 AML model, and cured all of the tumor-bearing mice in the MV4-11 AML model. The antitumor activity of RF-1302 was superior to gilteritinib (TGI=46-55%) and midostaurin (TGI=63-75%). The treatment with RF-1302 showed very little toxicity (only 2% body weight loss) which were well below the maximum tolerated dose. These preclinical results suggest that RF-1302 represents a novel dual inhibitor of PIM1 and FLT3, which may constitute a highly efficacious modality for the treatment of FLT3 mutant AML, and is worthy of further clinical evaluation.

Citation Format: Weiwei Qi, Yanjun Zhang, Lei Zhao, Ailian Zhang, Chunze Zhang, Xiaoming Zhang, Lijuan Li, Huaquan Wang, Zonghong Shao, Rong Fu. RF-1302, a novel dual inhibitor of PIM1 and FLT3 in preclinical treatment of acute myeloid leukemia. [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5269.

Robotic versus laparoscopic left colectomy with complete mesocolic excision for left-sided colon cancer: a multicentre study with propensity score matching analysis

BACKGROUND

Robotic surgery for right-sided colon and rectal cancer has rapidly increased; however, there is limited evidence in the literature of advantages of robotic left colectomy (RLC) for left-sided colon cancer. The purpose of this study was to compare the outcomes of RLC versus laparoscopic left colectomy (LLC) with complete mesocolic excision (CME) for left-sided colon cancer.

METHODS

Patients who had RLC or LLC with CME for left-sided colon cancer at 5 hospitals in China between January 2014 and April 2022 were included. A one-to-one propensity score matched analysis was performed to decrease confounding. The primary outcome was postoperative complications occurring within 30 days of surgery. Secondary outcomes were disease-free survival, overall survival and the number of harvested lymph nodes.

RESULTS

A total of 292 patients (187 males; median age 61.0 [20.0-85.0] years) were eligible for this study, and propensity score matching yielded 102 patients in each group. The clinical-pathological characteristics were well-matched between groups. The two groups did not differ in estimated blood loss, conversion to open rate, time to first flatus, reoperation rate, or postoperative length of hospital stay (p > 0.05). RLC was associated with a longer operation time (192.9 ± 53.2 vs. 168.9 ± 52.8 minutes, p=0.001). The incidence of postoperative complications did not differ between the RLC and LLC groups (18.6% vs. 17.6%, p = 0.856). The total number of lymph nodes harvested in the RLC group was higher than that in the LLC group (15.7 ± 8.3 vs. 12.1 ± 5.9, p< 0.001). There were no significant differences in 3-year and 5-year overall survival or 3-year and 5-year disease-free survival.

CONCLUSIONS

Compared to laparoscopic surgery, RLC with CME for left-sided colon cancer was found to be associated with higher numbers of lymph nodes harvested and similar postoperative complications and long-term survival outcomes.

Two-dimensional chromatography in screening of bioactive components from natural products

INTRODUCTION

Screening and analysis of bioactive components from natural products is a fundamental part of new drug development and innovation. Two-dimensional (2D) chromatography has been demonstrated to be an effective method for screening and preparation of specific bioactive components from complex natural products.

OBJECTIVE

To collect details of application of 2D chromatography in screening of natural product bioactive components and to outline the research progress of different separation mechanisms and strategies.

METHODOLOGY

Three screening strategies based on 2D chromatography are reviewed, including traditional separation-based screening, bioactivity-guided screening and affinity chromatography-based screening. Meanwhile, in order to cover these aspects, selections of different separation mechanisms and modes are also presented.

RESULTS

Compared with traditional one-dimensional (1D) chromatography, 2D chromatography has unique advantages in terms of peak capacity and resolution, and it is more effective for screening and identifying bioactive components of complex natural products.

CONCLUSION

Screening of natural bioactive components using 2D chromatography helps separation and analysis of complex samples with greater targeting and relevance, which is very important for development of innovative drug leads.

Higher long-term mortality in patients with concomitant acute coronary syndrome and aortic stenosis

Background

Aortic stenosis (AS) and acute coronary syndrome (ACS) share similar cardiovascular risk factors, and their concomitant presentation is increasing in incidence with the aging population. Yet literature regarding the prognosis of patients with concomitant ACS and AS remains scarce.

Methods

This retrospective cohort study examined consecutive patients presenting with ACS (ST-segment elevation myocardial infarction [STEMI] and non-STEMI [NSTEMI]) and concomitant AS between 1 January 2011 and 31 March 2021 in a tertiary hospital. The cohort was divided into mild, moderate and severe AS based on index echocardiogram. The primary outcome was all-cause mortality. Kaplan-Meier curves were constructed to compare all-cause mortality among the three groups of patients, based on ACS type and left ventricular ejection fraction (LVEF). Multivariable Cox regression was performed to identify independent predictors of all-cause mortality.

Results

Of a total of 563 patients, 264 had mild (46.9%), 193 moderate (34.3%) and 106 severe AS (18.8%). The mean follow-up duration was 2.5 (± 2.4) years. Majority of patients (72.5%) presented with NSTEMI. Patients with moderate and severe AS had higher rates of all-cause mortality compared to those with mild AS (49.7% vs. 51.4% vs. 35.6% respectively, p=0.002). Concomitant moderate (HR 1.439, 95% CI 1.012–2.048, p=0.043) and severe AS (HR 1.844, 95% CI 1.159–2.933, p=0.010) were independent predictors of all-cause mortality after adjusting for age, gender, LVEF, ACS type, chronic kidney disease, diabetes, hypertension, coronary artery bypass grafting and aortic valve replacement as a time-dependent variable. The Kaplan-Meier curves demonstrated excess mortality in moderate and severe AS, compared to the mild AS group (p&lt;0.001), with similar survival trends observed in the STEMI and the NSTEMI groups, as well as those with preserved LVEF.

Conclusion

Regardless of the ACS presentation type, long-term excess mortality in those with concomitant moderate or severe AS was observed. The adverse prognosis typically observed in patients with concomitant severe AS, in the setting of ACS, extends to patients with moderate AS.

Funding Acknowledgement

Type of funding sources: None.

Prognostically distinct phenotypes of metabolic health beyond obesity in aortic stenosis

Background

Whilst current evidence are in favour of metabolic health and non-obesity in the reduction of incident cardiovascular disease, little is known regarding the prognosis across the metabolic phenotypes once cardiovascular disease occurs. This study examined the prognosis of patients with significant aortic stenosis (AS) based on the presence of metabolic health and obesity.

Methods

This retrospective cohort on consecutive patients presenting with moderate-to-severe AS to a tertiary hospital between 2010 and 2015. Patients were allocated into 4 groups based on obesity and metabolic health: metabolically healthy obese (MHO), metabolically healthy non-obese (MHNO), metabolically unhealthy obese (MUO) and metabolically unhealthy non-obese (MUNO). Metabolic health was defined in accordance to Program Adult Treatment Panel III criteria. The primary outcome was all-cause mortality. Cox regression examined independent associations between mortality and metabolic phenotypes, adjusting for aortic valve area, ejection fraction, age, sex, chronic kidney disease and AVR as a time-dependent covariate.

Results

Of 727 patients, the majority (51.6%) were MUNO, followed by MUO (32.7%), MHNO (11.4%), and MHO (4.3%). MHNO had the highest mortality (43.0%), followed by the MUNO (37.5%), MUO (30.0%) and MHO (6.9%) groups (p=0.001). Compared to MHNO, MHO (HR 0.159, 95% CI 0.038–0.668, p=0.012) and MUO (HR 0.614, 95% CI 0.403–0.937, p=0.024) were independently associated with lower all-cause mortality rates, after adjusting for confounders. In obese patients, metabolic health had favourable survival compared to metabolically unhealthy (p=0.015), but this protective impact of metabolic health was not observed in overweight or normal weight individuals. Obesity had favourable survival compared to overweight and normal weight, in both metabolically health (p=0.002) and unhealthy (p=0.007) patients,

Conclusion

MHO patients with AS have the most favourable prognosis whilst the seemingly healthy MHNO group had the worst survival. There should be a paradigm shift towards prioritising metabolic health rather than weight reduction in patients with significant AS.

Funding Acknowledgement

Type of funding sources: None.

Chemical composition and adjuvant properties of the macromolecules from cultivated Cistanche deserticola Y. C. Ma as an immunopotentiator

The study aims to investigate the constituents, adjuvant effects, and underlying mechanisms of purified polysaccharides from cultivated Cistanche deserticola (C. deserticola). Two macromolecules designated as CCDP-1 (26.5 kDa) and CCDP-2 (32.3 kDa) from C. deserticola were respectively identified as carbohydrate-lignin complexes with 44.1 % and 43.8 % lignin. CCDP-1 and CCDP-2 were composed of glucose, rhamnose, galactose, arabinose, and mannose respectively in the molar ratios of 7.22: 5.98:2.51:1.81:1.00 and 6.57:8.48:4.20:2.72:1.00. An in vitro experiment revealed that endotoxin-free CCDP-1 and CCDP-2 promoted splenocyte proliferation without cytotoxicity, but CCDP-2 induced dendritic cell (DC) maturation more efficiently than CCDP-1. An in vivo experiment suggested that CCDP-2 enhanced OVA-specific antibody production, antigen-specific T-cell activation, IFN-γ production, IL-4 production, and DC activation. Notably, CCDP-2 elicited a Th1-biased response. Mechanically, CCDP-2 upregulated CD40, CD80, CD86, and MHC II, facilitated allogeneic T-cell proliferation and Th1/Th2 cytokines, improved IFN-γ, IL-12, IL-6, and TNF-α production, and decreased endocytosis from DCs in vitro. Blocking assays indicated that TLR2 and TLR4 were the membrane receptor candidates of DCs. Western blot implied that CCDP-2 with the immune-enhancing activities were involved in the activation of MAPKs and NF-κB pathways in a dose-/time-related manner and could be employed as a more balanced Th1/Th2 adjuvant for vaccine exploitation.

Improving adjuvanticity of crude polysaccharides from cultivated Artemisia rupestris L. for influenza vaccine by promoting long-term immunity and TH1/TH2 response with dose-sparing effect

ETHNOPHARMACOLOGICAL RELEVANCE

Influenza virus vaccines (IVV) with balanced T_H1/T_H2 responses are critical for controlling seasonal influenza. Emerging evidences suggest that herbal polysaccharides can induce potent T_H1 or mixed T_H1/T_H2 responses.

AIM OF STUDY

The study aims to determine the efficacy and safety of crude polysaccharides from cultivated Artemisia rupestris L. (CPCAR) as an adjuvant for IVV.

MATERIALS AND METHODS

CPCAR was prepared with hot extraction and ethanol precipitation method and primary physico-chemical characters were tested. Mice were vaccinated by subcutaneous route with IVV formulated with different dose of CPCAR to detecting the elicited T_H1/T_H2 responses and long-term immune responses with dose-sparing sparing effect.

RESULTS

IVV formulated with CPCAR without LPS contamination could augment balanced T_H1/T_H2 responses, as indicated by early IgG response, hemagglutination inhibition (HAI) antibodies, effector T-cells, and cytotoxic T lymphocytes (CTL). Moreover, CPCAR elicited long-term IgG, HAI antibodies, memory T cells, and balanced CD4/CD8 responses within 168 days after vaccination. Compared with IVV alone, a low or high dose of IVV formulated with CPCAR improved the levels of IgG, IgG1, and IgG2a and enhanced memory T cells and balanced CD4/CD8 responses, displaying a 10-fold dose-sparing effect. As determined by IgE response and monitoring results of weekly body weight and daily symptoms after vaccination, anaphylaxis or adverse effect was not observed.

CONCLUSIONS

Collectively, the study demonstrated the potential of CPCAR as an aqueous polysaccharide adjuvant for IVV to induce rapid and balanced T_H1/T_H2 responses and long-lasting immunity with dose-sparing effect.

Isolation, characterization of bamboo leaf flavonoids by size exclusion chromatography and their antioxidant properties

The utilization of bamboo industry exhibits varied but still needs to be improved. Bamboo leaf flavonoid (BLF) is an important resource of bamboo which has become a research focus. However, the isolation and purification techniques of four flavonoid carbon glycosides (orientin, isoorientin, vitexin, and isovitexin) from BLF were still confronted with difficulties due to their complex and similar structures, which obstructed the development of bamboo utilization. In this paper, a purification technology of four flavonoid carbon glycosides from BLF by Sephadex LH-20 was improved. The results were evaluated by HPLC and pharmacological activity. Specifically, the eluent, flow rate, and loading amount were investigated respectively. According to the results, the eluent would dominate the isolation effect among three factors. High concentration of isoorientin and four flavonoid carbon glycosides would be obtained under the optimized condition (The eluent was 70% methanol, the loading amount was 1.5 g, and the flow rate was 0.5 mL·min-1). Meanwhile, the link between flavonoid carbon glycosides content and their antioxidant activity in vitro was also revealed. Overall, the results suggested that BLF may serve as potential functional food additives and medicine.

A scintillator attenuation spectrometer for intense gamma-rays

A new type of compact high-resolution high-sensitivity gamma-ray spectrometer for short-pulse intense gamma-rays (250 keV to 50 MeV) has been developed by combining the principles of scintillators and attenuation spectrometers. The first prototype of this scintillator attenuation spectrometer (SAS) was tested successfully in Trident laser experiments at LANL. Later versions have been used extensively in the Texas Petawatt laser experiments in Austin, TX, and more recently in OMEGA-EP laser experiments at LLE, Rochester, NY. The SAS is particularly useful for high-repetition-rate laser applications. Here, we give a concise description of the design principles, capabilities, and sample preliminary results of the SAS.

OP0015 PROINFLAMMATORY MONOCYTES AND MACROPHAGES IN SYNOVIAL FLUID AND BURSAL TISSUE OF PATIENTS WITH POLYMYALGIA RHEUMATICA: POTENT PRODUCERS OF IL-6 AND GM-CSF

Background

Polymyalgia rheumatica (PMR) is a common, rheumatic inflammatory disease. Inflammation of bursae and tendon sheaths is a characteristic finding in patients with PMR. Glucocorticoid treatment remains the mainstay treatment for PMR. A study published in 1996 reported that macrophages dominate the inflammatory infiltrates in the glenohumeral synovium of PMR patients1, suggesting the importance of these cells in the immunopathology of PMR. However, the functional and phenotypical heterogeneity of the tissue-infiltrating macrophages in PMR remains obscure. Although treatment with anti-IL-6 receptor (tocilizumab) has shown promising results2, it is unclear whether macrophages contribute to IL-6 production in PMR. Additionally, anti-GM-CSF receptor therapy (mavrilimumab), recently shown to be efficacious in the closely related disease giant cell arteritis3, may also be useful for the treatment of PMR. Knowledge on the functional heterogeneity of monocytes/macrophages in PMR may aid in identifying novel therapeutic targets for this condition.

Objectives

To determine the phenotype of monocyte/macrophages in peripheral blood, bursal/tenosynovial fluid and bursal tissue of patients with PMR.

Methods

Paired peripheral blood (PB), bursal/tenosynovial fluid (SF) and bursal tissue biopsy samples from 11 PMR patients were included in our study. Bursal and tenosynovial samples were obtained from the shoulder. Distribution of the monocyte subsets (classical, intermediate and non-classical monocytes) was determined based on the level of CD14 and CD16 expression by flow cytometry. To study monocyte activation status, markers of ‘M1’ like (CD80 and CD64) and ‘M2’ like (CD206 and FRβ) macrophage polarization were included in the flow cytometry analysis. Immunohistochemistry of bursal tissue biopsies was focused on macrophage markers (CD68, CD86, CD64, CD206 and FRβ) andproinflammatory cytokines (IL-6 and GM-CSF), which were scored semi-quantitatively. Double immunofluorescence stainings were performed to determine the expression of IL-6 and GM-CSF by tissue-infiltrating macrophages in bursal tissue.

Results

Monocytes were detected in the SF of PMR patients. The proportion of classical monocytes was significantly lowered (p=0.001) in SF versus PB, while the proportion of intermediate monocytes was significantly elevated (p=0.001). The expression of CD206 was significantly elevated (p=0.001) but not FRβ in SF monocytes, suggesting GM-CSF skewed phenotype. In bursal tissue, macrophages displayed mixed ‘M1’/’M2’ traits with high expression of all macrophage polarization markers. Proinflammatory cytokines IL-6 and GM-CSF were highly expressed throughout the bursal tissue biopsies. Double immunofluorescence staining confirmed the expression of IL-6 and GM-CSF by the infiltrating macrophages.

Conclusion

SF monocytes and bursal tissue macrophages show a pro-inflammatory phenotype in PMR. Moreover, tissue-infiltrating macrophages show a prominent IL-6 and GM-CSF response in PMR. Our data add to the rationale of targeting IL-6 and GM-CSF as treatment options in PMR.

References

[1]Meliconi R, Pulsatelli L, Uguccioni M, et al. Leukocyte infiltration in synovial tissue from the shoulder of patients with polymyalgia rheumatica. Quantitative analysis and influence of corticosteroid treatment. Arthritis Rheum. 1996;39(7):1199-1207.

[2]Devauchelle-Pensec V, Berthelot JM, Cornec D, et al. Efficacy of first-line tocilizumab therapy in early polymyalgia rheumatica: a prospective longitudinal study. Ann Rheum Dis. 2016;75(8):1506-1510.

[3]Cid MC, Unizoni S, Pupim L, et al. Mavrilimumab (anti GM-CSF Receptor α Monoclonal Antibody) Reduces Time to Flare and Increases Sustained Remission in a Phase 2 Trial of Patients with Giant Cell Arteritis [Abstract]. Arthritis Rheumatol. 2020; 72 (suppl 10).

Acknowledgements

This work was supported by a research grant from FOREUM Foundation for Research in Rheumatology. The PMR Research On disease Mechanisms In Synovium (PROMIS) study was also funded by the Rheumatology Grant (Dutch Society for Rheumatology) and Mandema Stipend (University Medical Center Groningen).

Disclosure of Interests

William Febry Jiemy: None declared, Rosanne Reitsema: None declared, Anqi Zhang: None declared, Maria Sandovici: None declared, Annemieke Boots: None declared, Peter Heeringa: None declared, Elisabeth Brouwer Speakers bureau: E. Brouwer reports speaker and consulting fees from Roche in 2017-2018, outside the submitted work, Consultant of: E. Brouwer reports speaker and consulting fees from Roche in 2017-2018, outside the submitted work, Kornelis van der Geest Consultant of: K. van der Geest reports personal fees from Roche, outside the submitted work.

Structural derivatization strategies of natural phenols by semi-synthesis and total-synthesis

Structural derivatization of natural products has been a continuing and irreplaceable source of novel drug leads. Natural phenols are a broad category of natural products with wide pharmacological activity and have offered plenty of clinical drugs. However, the structural complexity and wide variety of natural phenols leads to the difficulty of structural derivatization. Skeleton analysis indicated most types of natural phenols can be structured by the combination and extension of three common fragments containing phenol, phenylpropanoid and benzoyl. Based on these fragments, the derivatization strategies of natural phenols were unified and comprehensively analyzed in this review. In addition to classical methods, advanced strategies with high selectivity, efficiency and practicality were emphasized. Total synthesis strategies of typical fragments such as stilbenes, chalcones and flavonoids were also covered and analyzed as the supplementary for supporting the diversity-oriented derivatization of natural phenols.

Thermal Analysis of PE Extended Chain Crystal of PE Extended Chain Crystal from Gel Spinning

It has been recognized that ultra-high strength and high modulus ultra-highly drawn Polyethylene (PE) fiber is produced from the formation of extended chain crystal. Nevertheless, whether extended chain crystal exists in gel spinning ultra-highly drawn PE fiber is still an unsettled question. In this work, decalin was adopted as a solvent for PE gel spinning. By means of thermal analysis, X-ray diffraction methods etc, the existence of extended chain crystal was explored. Reasons for confusion in previous studies of this problem were discussed.

In PE fiber from 3 wt-°/o dope, extended chain crystal starts to form during draw ratios over 20. When draw ratio equals 42, the content of extended chain crystal roughly equals that of folded chain crystal. The melting point of extended chain crystal is 6°C higher than that of folded chain crystal. They are 145.5° C and 150° C to 152.5° C respectively. The latter would slightly rise with arise of draw ratio.

Multi-crystallization behavior of annealed PE fiber was determined and discussed. It was also confirmed that there is a linear logarithm relationship between thermal shrinkage (internal stresses) and fiber moduli.

Evidence for X(3872) in Pb-Pb Collisions and Studies of its Prompt Production at sqrt[s_{NN}]=5.02 TeV

The first evidence for X(3872) production in relativistic heavy ion collisions is reported. The X(3872) production is studied in lead-lead (Pb-Pb) collisions at a center-of-mass energy of sqrt[s_{NN}]=5.02  TeV per nucleon pair, using the decay chain X(3872)→J/ψπ^{+}π^{-}→μ^{+}μ^{-}π^{+}π^{-}. The data were recorded with the CMS detector in 2018 and correspond to an integrated luminosity of 1.7  nb^{-1}. The measurement is performed in the rapidity and transverse momentum ranges |y|<1.6 and 15<p_{T}<50  GeV/c. The significance of the inclusive X(3872) signal is 4.2 standard deviations. The prompt X(3872) to ψ2S yield ratio is found to be ρ^{Pb-Pb}=1.08±0.49(stat)±0.52(syst), to be compared with typical values of 0.1 for pp collisions. This result provides a unique experimental input to theoretical models of the X(3872) production mechanism, and of the nature of this exotic state.

Long noncoding RNA RP11-909N17.2 presages a poor prognosis of non-small cell lung cancer

BACKGROUND

Long non-coding RNAs (lncRNAs) were detected extraordinarily expressed in various tumors and could combine with microRNAs (miRNAs) to play important role in tumor cells. This study is to explore the role of lncRNA RP11-909N17.2 in NSCLC and discuss in what way it functions in NSCLC.

METHODS

120 NSCLC patients were enlisted in this study. Expression levels of lncRNA RP11-909N17.2 and miR-767-3p were detected and the correlation between lncRNA RP11-909N17.2 expression and the clinical data characteristics was analyzed. Prognosis potential of lncRNA RP11-909N17.2 was inferred with Kaplan-Meier and multivariate Cox regression assays. Biological functions of NSCLC cells were accessed by cell counting Kit-8, transwell migration and invasion assay. Mechanism of RP11-909N17.2 action on NSCLC cells was investigated by luciferase activity assay with wide-type or mutation.

RESULTS

LncRNA RP11-909N17.2 has an ascendant expression while miR-767-3p has descended one in NSCLC tissue specimens and cells. Over-expression of lncRNA RP11-909N17.2 can shorten the overall survival period of NSCLC patients when compared with low expression. Knockdown of lncRNA RP11-909N17.2 suppressed biology function of NSCLC cell including proliferation, migration, and invasion.

CONCLUSION

LncRNA RP11-909N17.2 can be developed into a prognostic index for NSCLC. LncRNA RP11-909N17.2 plays a promoting role in NSCLC cells possibly by binding miR-767-3p as a sponge.

An application research for near-surface repository of strontium-90 sorption kinetic model on mudrocks

In this study,90Sr was used as the test radionuclide to characterize the sorption kinetics and effects of initial 90Sr activity and remaining 90Sr in solid concentration were simulated for a near-surface repository. The study focused on the sorption characteristics of radionuclides in unsaturated groundwater environment (or vadose zone) is the important information for investigating the near-surface disposal of intermediate and low-level radioactive waste (ILLW). Moreover, the 90Sr sorption experiments reached equilibrium within 56 h, which fit to the first order sorption kinetic model, and the remaining 90Sr in mudrock samples showed obvious sorption equilibrium hysteresis, which fit to the second order sorption kinetic model. Before reaching the maximum sorption capacity, the sorption rate constant increases with 90Sr increasing; the distribution coefficient (Kd) of 56 h decreases with the remaining 90Sr decreasing. In addition, it showed that the slow sorption process dominated before the sorption reaches equilibrium. In fact, a reliable safety assessment methodology for on-going near-surface repository required a lot of the radionuclides parameters with local environment including the radionuclides sorption/desorption rate constant and maximum sorption capacity.

Robust Evaluation of Ultraviolet-C Sensitivity for SARS-CoV-2 and Surrogate Coronaviruses

UV light, more specifically UV-C light at a wavelength of 254 nm, is often used to disinfect surfaces, air, and liquids. In early 2020, at the cusp of the COVID-19 pandemic, UV light was identified as an efficient means of eliminating coronaviruses; however, the variability in published sensitivity data is evidence of the need for experimental rigor to accurately quantify the effectiveness of this technique. In the current study, reliable and reproducible UV techniques have been adopted, including accurate measurement of light intensity, consideration of fluid UV absorbance, and confirmation of uniform dose delivery, including dose verification using an established biological target (T1UV bacteriophage) and a resistant recombinant virus (baculovirus). The experimental results establish the UV sensitivity of SARS-CoV-2, HCoV-229E, HCoV-OC43, and mouse hepatitis virus (MHV) and highlight the potential for surrogate viruses for disinfection studies. All four coronaviruses were found to be easily inactivated by 254 nm irradiation, with UV sensitivities of 1.7, 1.8, 1.7, and 1.2 mJ/cm2/log10 reduction for SARS-CoV-2, HCoV-229E, HCoV-OC43, and MHV, respectively. Similar UV sensitivities for these species demonstrate the capacity for HCoV-OC43, HCoV-229E, and MHV to be considered surrogates for SARS-CoV-2 in UV-inactivation studies, greatly reducing hazards and simplifying procedures for future experimental studies. IMPORTANCE Disinfection of SARS-CoV-2 is of particular importance due to the global COVID-19 pandemic. UV-C irradiation is a compelling disinfection technique because it can be applied to surfaces, air, and water and is commonly used in drinking water and wastewater treatment facilities. UV inactivation depends on the dose received by an organism, regardless of the intensity of the light source or the optical properties of the medium in which it is suspended. The 254 nm irradiation sensitivity was accurately determined using benchmark methodology and a collimated beam apparatus for four coronaviruses (SARS-CoV-2, HCoV-229E, HCoV-OC43, and MHV), a surrogate indicator organism (T1UV), and a resistant recombinant virus (baculovirus vector). Considering the light distribution across the sample surface, the attenuation of light intensity with fluid depth, the optical absorbance of the fluid, and the sample uniformity due to mixing enable accurate measurement of the fundamental inactivation kinetics and UV sensitivity.

Aqueous extracts from cultivated Cistanche deserticola Y.C. Ma as polysaccharide adjuvant promote immune responses via facilitating dendritic cell activation

ETHNOPHARMACOLOGICAL RELEVANCE

Herbal polysaccharides have exhibited great immune-enhancing potential. Adjuvants are a key tool for developing efficacious vaccines. In our previous study, a water-soluble polysaccharide extracted from wild Cistanche deserticola Y.C. Ma showed potent immunostimulatory activity.

AIM OF STUDY

In this study, the immune profiles and efficacy of aqueous extracts of cultivated Cistanche deserticola Y.C. Ma (AECCD) on ICR mice against ovalbumin (OVA) were investigated. In vitro experiments, the possible DC activation mechanism by AECCD was evaluated.

MATERIALS AND METHODS

AECCD were extracted using hot water after which the crude polysaccharides were precipitated by ethanol. Mice were firstly immunized subcutaneously with OVA (10 μg per mouse) alone or OVA (10 μg per mouse) respectively containing different dose of AECCD (200, 400 and 800 μg per mouse) on Days 1 and 14 and the magnitude and kinetics of antibodies and cell-mediated responses were then assessed.

RESULTS

AECCD elicited vigorous and long-term IgG responses with mixed Th1/Th2 responses and up-regulated levels of Th-associated cytokines (CD4⁺IL-4, CD4⁺IFN-γ and CD8⁺IFN-γ). Moreover, AECCD induced the strong cellular immune response characterized by increased splenocyte proliferation as well as the activated T cell response. Notably, AECCD significantly enhanced the maturation of dendritic cells (DCs) and inhibited Tregs. In vitro experiments, Preliminary tests indicated that AECCD induced DC activation by promoting phenotypic maturation, cytokine section and allostimulatory activity. Toll-like receptor 4 (TLR4) was an essential receptor for DCs to directly bind AECCD. The inhibitors of NF-κB decreased the expression levels of CD40, CD80, CD86 and MHC-II and the production of IFN-γ, TNF-α and IL-6 through DCs.

CONCLUSIONS

Finally, these findings suggested that AECCD could elicit potent and durable antigen specific immune responses through DC activation, which was involved in the regulation of maturation markers and cytokine expression via TLR4-related NF-κB pathway. The study indicates that AECCD is a potential immunomodulator.

Isobutanol tolerance and production of Saccharomyces cerevisiae can be improved by engineering its TATA-binding protein Spt15

Low isobutanol tolerance of Saccharomyces cerevisiae limits its application in isobutanol fermentation. Here, we used global transcription machinery engineering to screen mutants with higher isobutanol tolerance and elevated isobutanol titres. TATA-binding protein Spt15 was used as the target of global transcription machinery engineering for improvement of such complex phenotypes. A random mutagenesis library of S. cerevisiae TATA-binding protein Spt15 was constructed and subjected to screening under isobutanol stress. A mutant strain (denoted as spt15-3) with improved isobutanol tolerance was identified. There were three mutations of Spt15 in strain spt15-3, including deletion of A at position -132 nt upstream of initiation codon, insertion of G at position -65 nt upstream of initiation codon and a synonymous mutation at position 315 nt (T → C) downstream of initiation codon. We then metabolically engineered isobutanol synthesis in strains harbouring plasmids YCplac22 containing these Spt15 mutations. Delta integration was used to overexpress ILV3 gene, and 2μ plasmids carrying PGK1p-ILV2 and PGK1p-ARO10 were used to overexpress ILV2 and ARO10 genes. After 24-h micro-aerobic fermentation, Engi-3 produced 0·556 g l^-1 isobutanol, which was 404% and 25·3% greater than isobutanol produced by control Engi-1 and engineered Engi-2, respectively. After 28 h, Engi-4 produced 0·459 g l^-1 isobutanol, which was 315% and 3·2% greater than isobutanol produced Engi-1 and Engi-2, respectively. RNA-Seq-based transcriptome analysis shows that mutations of Spt15 in strain spt15-3 increased the expression of SPT15. Meanwhile, compared with strain Engi-3, the spt15-3 mutation downregulated the expression of genes involved in the TCA cycle and glyoxylic acid cycle, but increased the expression of genes related to cell stability. This work demonstrates that isobutanol tolerance and production of S. cerevisiae can be improved by engineering its TATA-binding protein Spt15. This study clarified the molecular mechanisms regulating isobutanol production and tolerance in S. cerevisiae.

A Review of Mechano-Biochemical Models for Testing Composite Restorations

Due to the severe mechano-biochemical conditions in the oral cavity, many dental restorations will degrade and eventually fail. For teeth restored with resin composite, the major modes of failure are secondary caries and fracture of the tooth or restoration. While clinical studies can answer some of the more practical questions, such as the rate of failure, fundamental understanding on the failure mechanism can be obtained from laboratory studies using simplified models more effectively. Reviewed in this article are the 4 main types of models used to study the degradation of resin-composite restorations, namely, animal, human in vivo or in situ, in vitro biofilm, and in vitro chemical models. The characteristics, advantages, and disadvantages of these models are discussed and compared. The tooth-restoration interface is widely considered the weakest link in a resin composite restoration. To account for the different types of degradation that can occur (i.e., demineralization, resin hydrolysis, and collagen degradation), enzymes such as esterase and collagenase found in the oral environment are used, in addition to acids, to form biochemical models to test resin-composite restorations in conjunction with mechanical loading. Furthermore, laboratory tests are usually performed in an accelerated manner to save time. It is argued that, for an accelerated multicomponent model to be representative and predictive in terms of both the mode and the speed of degradation, the individual components must be synchronized in their rates of action and be calibrated with clinical data. The process of calibrating the in vitro models against clinical data is briefly described. To achieve representative and predictive in vitro models, more comparative studies of in vivo and in vitro models are required to calibrate the laboratory studies.

P–138 When is low quality really low? Should we transfer low-grade blastocysts?

Study question

What is the live birth rate after single, low-grade blastocyst (LGB) transfer?

Summary answer

The live birth rate for LGBs is 28%, ranging between 15–31% for the different inner cell mass (ICM) and trophectoderm (TE) subgroups of LGBs.

What is known already

Live birth rates following LGB transfer are varied and have been reported to be in the range of 5–39%. However, these estimates are inaccurate as studies investigating live birth rates following LGB transfer are inherently limited by sample size (n = 10–440 for LGB transfers) due to LGBs being ranked last for transfer. Further, these studies are heterogenous with varied LGB definitions and design. Collating LGB live birth data from multiple clinics is warranted to obtain sufficient numbers of LGB transfers to establish reliable live birth rates, and to allow for delineation of different LGB subgroups, including blastocyst age and female age.

Study design, size, duration

We performed a multicentre, multinational retrospective cohort study in 9 IVF centres in China and New Zealand from 2012 to 2019. We studied the outcome of 6966 single blastocyst transfer cycles on days 5–7 (fresh and frozen) according to blastocyst grade, including 875 transfers from LGBs (&lt;3bb, this being the threshold typically applied to LGB studies). Blastocysts with expansion stage 1 or 2 (early blastocysts) were excluded.

Participants/materials, setting, methods

The main outcome measured was live birth rate. Blastocysts were grouped according to quality grade: good-grade blastocysts (GGBs; n = 3849, aa, ab and ba), moderate-grade blastocysts (MGBs; n = 2242, bb) and LGBs (n = 875, ac, ca, bc, cb and cc) and live birth rates compared using the Pearson Chi-squared test. A logistic regression analysis explored the relationship between blastocyst grade and live birth after adjustment for the confounders: clinic, female age, expansion stage, and blastocyst age.

Main results and the role of chance

The live birth rates for GGBs, MGBs and LGBs were 45%, 36% and 28% respectively (p &lt; 0.0001). Within the LGB group, the highest live birth rates were for grade c TE (30%) and the lowest were for grade c ICM (19%). The lowest combined grade (cc) maintained a 15% live birth rate (n = 7/48). After accounting for confounding factors, including female age and blastocyst characteristics, the odds of live birth were 2.33 (95% CI = 1.88–2.89) for GGBs compared to LGBs and 1.56 (95% CI = 1.28–1.92) for MGBs compared to LGBs following fresh and frozen blastocyst transfers (p &lt; 0.0001, odds ratios confirmed in exclusively frozen blastocyst transfer cycles). When stratified by individual ICM and TE grade, the odds of live birth according to ICM grade were 1.31 (a versus b; 95% CI = 1.15–1.48), 2.82 (a versus c; 95% CI = 1.91–4.18) and 2.16 (b versus c; 95% CI = 1.48–3.16; all p &lt; 0.0001). The odds of live birth according to TE grade were 1.33 (a versus b; 95% CI = 1.17–1.50, p &lt; 0.0001), 1.85 (a versus c; 95% CI = 1.45–2.34, p &lt; 0.0001) and 1.39 (b versus c; 95% CI = 1.12–1.73, p = 0.0024).

Limitations, reasons for caution

Despite the large multicentre design of the study, analyses of transfers occurring within the smallest subsets of the LGB group were limited by sample size. The study was not randomised and had a retrospective character.

Wider implications of the findings: LGBs maintain satisfactory live birth rates (averaging 28%) in the general IVF population. Even those in the lowest grading tier maintain modest live birth rates (15%; cc). It is recommended that LGBs not be universally discarded, and instead considered for subsequent frozen embryo transfer to maximize cumulative live birth rates.

Trial registration number

Not applicable

Second-trimester abdominal circumference discordance and adverse perinatal outcomes in monochorionic twins

OBJECTIVE

The perinatal outcomes in second-trimester abdominal circumference (AC) discordant twins are yet to be established. The aim of this study was to ascertain perinatal risks associated with second-trimester AC discordance in monochorionic (MC) twins.

METHOD

We conducted a retrospective study of all MC twin pregnancies over a 7-year period. Intertwin AC discordance at 14-26 gestational weeks was analyzed in relation to Doppler abnormalities, obstetric complications, and perinatal adverse outcomes.

RESULTS

A total of 246 MC twin pregnancies were included in the analysis. The smaller twins of second-trimester AC discordant pairs were at increased prevalence of abnormal umbilical artery flow (50% versus 24%, p < .001) and low positive A wave of ductus venous flow (24% versus 9%, p = .002). The second-trimester AC discordant twins were at increased risk of oligohydramnios in smaller twin (OR = 2.44, 95% CI = 1.37-4.32, p < .01), cardiomegaly in larger twin (OR = 2.95, 95% CI = 1.01-8.60, p < .05), birth weight of either twin below the 10th percentile for gestational age (OR = 5.56, 95% CI = 2.67-11.59, p < .001), birth weight discordance > 25% (OR = 9.41, 95% CI = 4.46-19.87, p < .001), IUFD (OR = 3.26, 95% CI = 1.76-6.05, p < .001), and severe neonatal morbidity (OR = 1.83, 95% CI = 1.03-3.26, p < .05). The intact survival rate in discordant and concordant twin pairs was 70% and 89%, respectively (p < .001).

CONCLUSIONS

Early and increase fetal surveillance of the second-trimester AC discordant twins should be utilized to establish perinatal risks, thus allowing prenatal care to improve.

Development and validation of HERWIG 7 tunes from CMS underlying-event measurements

This paper presents new sets of parameters ("tunes") for the underlying-event model of the H E R W I G 7 event generator. These parameters control the description of multiple-parton interactions (MPI) and colour reconnection in H E R W I G 7 , and are obtained from a fit to minimum-bias data collected by the CMS experiment at s = 0.9 , 7, and 13 Te . The tunes are based on the NNPDF 3.1 next-to-next-to-leading-order parton distribution function (PDF) set for the parton shower, and either a leading-order or next-to-next-to-leading-order PDF set for the simulation of MPI and the beam remnants. Predictions utilizing the tunes are produced for event shape observables in electron-positron collisions, and for minimum-bias, inclusive jet, top quark pair, and Z and W boson events in proton-proton collisions, and are compared with data. Each of the new tunes describes the data at a reasonable level, and the tunes using a leading-order PDF for the simulation of MPI provide the best description of the data.

Nanostructured RuO2-Co3O4@RuCo-EO with low Ru loading as a high-efficiency electrochemical oxygen evolution catalyst

Electrochemical water splitting technology is considered to be the most reliable method for converting renewable energy such as wind and solar energy into hydrogen. Here, a nanostructured RuO₂/Co₃O₄–RuCo-EO electrode is designed via magnetron sputtering combined with electrochemical oxidation for the oxygen evolution reaction (OER) in an alkaline medium. The optimized RuO₂/Co₃O₄–RuCo-EO electrode with a Ru loading of 0.064 mg cm⁻² exhibits excellent electrocatalytic performance with a low overpotential of 220 mV at the current density of 10 mA cm⁻² and a low Tafel slope of 59.9 mV dec⁻¹ for the OER. Compared with RuO₂ prepared by thermal decomposition, its overpotential is reduced by 82 mV. Meanwhile, compared with RuO₂ prepared by magnetron sputtering, the overpotential is also reduced by 74 mV. Furthermore, compared with the RuO₂/Ru with core–shell structure (η = 244 mV), the overpotential is still decreased by 24 mV. Therefore, the RuO₂/Co₃O₄–RuCo-EO electrode has excellent OER activity. There are two reasons for the improvement of the OER activity. On the one hand, the core–shell structure is conducive to electron transport, and on the other hand, the addition of Co adjusts the electronic structure of Ru.

The optimized RuO₂/Co₃O₄–RuCo-EO electrode with Ru loading of 0.064 mg cm⁻² exhibits the excellent oxygen evolution activity with an overpotential of 220 mV at the current density of 10 mA cm⁻² and a Tafel slope of 59.9 mV dec⁻¹.

EpsR Negatively Regulates Streptococcus mutans Exopolysaccharide Synthesis

Streptococcus mutans is considered the primary etiological agent of human dental caries. Glucosyltransferases (Gtfs) from S. mutans play important roles in the formation of biofilm matrix and the development of cariogenic oral biofilm. Therefore, Gtfs are considered an important target to prevent the development of dental caries. However, the role of transcription factors in regulating gtf expression is not yet clear. Here, we identify a MarR (multiple antibiotic resistance regulator) family transcription factor named EpsR (exopolysaccharide synthesis regulator), which negatively regulates gtfB expression and exopolysaccharide (EPS) production in S. mutans. The epsR in-frame deletion strain grew slowly, aggregated more easily in the presence of dextran, and displayed different colony morphology and biofilm structure. Notably, epsR deletion resulted in altered 3-dimensional biofilm architecture, increased water-insoluble EPS production, and upregulated GtfB protein content and activity. In addition, global gene expression profiling revealed differences in the expression levels of 69 genes in which gtfB was markedly upregulated. The conserved DNA motif for EpsR binding was determined by electrophoretic mobility shift assay and DNase I footprinting assays. Moreover, analysis of β-galactosidase activity suggested that EpsR acted as a repressor and inhibited gtfB expression. Taken together, our findings indicate that EpsR is an important transcription factor that regulates gtfB expression and EPS production in S. mutans. These results add new aspects to the complexity of regulating the expression of genes involved in the cariogenicity of S. mutans, which might lead to novel strategies to prevent the formation of cariogenic biofilm that may favor diseases.

Enhancing immune responses to inactivated foot-and-mouth virus vaccine by a polysaccharide adjuvant of aqueous extracts from Artemisia rupestris L

BACKGROUND

New-generation adjuvants for foot-and-mouth disease virus (FMDV) vaccines can improve the efficacy of existing vaccines. Chinese medicinal herb polysaccharide possesses better promoting effects.

OBJECTIVES

In this study, the aqueous extract from Artemisia rupestris L. (AEAR), an immunoregulatory crude polysaccharide, was utilized as the adjuvant of inactivated FMDV vaccine to explore their immune regulation roles.

METHODS

The mice in each group were subcutaneously injected with different vaccine formulations containing inactivated FMDV antigen adjuvanted with three doses (low, medium, and high) of AEAR or AEAR with ISA-206 adjuvant for 2 times respectively in 1 and 14 days. The variations of antibody level, lymphocyte count, and cytokine secretion in 14 to 42 days after first vaccination were monitored. Then cytotoxic T lymphocyte (CTL) response and antibody duration were measured after the second vaccination.

RESULTS

AEAR significantly induced FMDV-specific antibody titers and lymphocyte activation. AEAR at a medium dose stimulated Th1/Th2-type response through interleukin-4 and interferon-γ secreted by CD4⁺ T cells. Effective T lymphocyte counts were significantly elevated by AEAR. Importantly, the efficient CTL response was remarkably provoked by AEAR. Furthermore, AEAR at a low dose and ISA-206 adjuvant also synergistically promoted immune responses more significantly in immunized mice than those injected with only ISA-206 adjuvant and the stable antibody duration without body weight loss was 6 months.

CONCLUSIONS

These findings suggested that AEAR had potential utility as a polysaccharide adjuvant for FMDV vaccines.

A6 THE ROLE OF TUFT CELLS IN INTESTINAL HOMEOSTASIS

Background

Intestinal epithelial cells may actively regulate homeostasis by recognizing and responding to extracellular signals. One of these cell types, tuft cells, has been proposed to have a role in secretion, absorption, and reception. However, their role in the intestine has not been fully characterized. We have found that tuft cells express the SH2 domain-containing inositol 5’-phosphatase (SHIP), which was formerly thought to be restricted to hematopoietic cells. SHIP negatively regulates PI3K-mediated cell growth, proliferation, and activation. Tuft cells secrete IL-25, which activates group 2 innate lymphoid cells (ILC2s), leading to type 2 immune responses. Tuft cells may contribute to inflammation in the intestine by increasing ILC2 numbers and/or activation, leading to type II inflammation.

Aims

My hypothesis is that SHIP inhibits tuft cell responses to innate immune stimuli by limiting PI3K activation. Moreover, SHIP deficiency will increase tuft cell responses to commensal microbes, causing ILC2-mediated type II inflammation. To investigate the role of SHIP in tuft cell responses in vivo, I will use a tuft cell-specific SHIP deficient mouse in the dextran sodium sulfate (DSS)-induced colitis model.

Methods

We created a mouse deficient in SHIP only in intestinal tuft cells (Fabpcre x SHIPfl/fl) to investigate the impact of SHIP deficiency in tuft cells on responses to luminal microbes. Tuft cell-specific SHIP deficient mice (8-week-old) and their wild type littermates were subjected to DSS-induced colitis for 7 days. Clinical disease activity was monitored daily and gross pathology, including total colon length, was examined at the experimental endpoint. The concentrations of pro-inflammatory type I and type II cytokines were assessed in colonic tissue homogenates via ELISA.

Results

During DSS-induced colitis, mice with SHIP deficient tuft cells had increased disease activity compared to their wild type littermates, particularly evident in their weight loss. Mice with SHIP deficient tuft cells also had significantly shorter colons than their wild type littermates. IL-25 concentrations (produced by tuft cells) were increased in full thickness colon homogenates from mice with SHIP deficient tuft cells. In contrast, pro-inflammatory cytokines IL-1β, IL-6, and TNF did not differ between genotypes. Thus, increased tuft cell activity due to SHIP deficiency correlated with increased disease severity during DSS-induced colitis.

Conclusions

SHIP deficiency in intestinal tuft cells leads to increased tuft cell activity and exacerbated colitis during DSS treatment. Tuft cells may contribute to inflammation via IL-25 production, leading to increased type II inflammation by ILC2s. In future studies, we will target IL-25 in this model to determine whether increased tuft cell IL-25 production plays a causal role in disease exacerbation.

Funding Agencies

NSERC