Survival of itinerant excitations and quantum spin state transitions in YbMgGaO4 with chemical disorder

A recent focus of quantum spin liquid (QSL) studies is how disorder/randomness in a QSL candidate affects its true magnetic ground state. The ultimate question is whether the QSL survives disorder or the disorder leads to a “spin-liquid-like” state, such as the proposed random-singlet (RS) state. Since disorder is a standard feature of most QSL candidates, this question represents a major challenge for QSL candidates. YbMgGaO₄, a triangular lattice antiferromagnet with effective spin-1/2 Yb³⁺ions, is an ideal system to address this question, since it shows no long-range magnetic ordering with Mg/Ga site disorder. Despite the intensive study, it remains unresolved as to whether YbMgGaO₄ is a QSL or in the RS state. Here, through ultralow-temperature thermal conductivity and magnetic torque measurements, plus specific heat and DC magnetization data, we observed a residual κ₀/T term and series of quantum spin state transitions in the zero temperature limit for YbMgGaO₄. These observations strongly suggest that a QSL state with itinerant excitations and quantum spin fluctuations survives disorder in YbMgGaO₄.

It remains an open question as to whether the quantum spin liquid state survives material disorder, or is replaced by some spin-liquid like state. Here, Rao et al succeed in resolving a resolving a κ₀/T residual in the thermal conductivity of YbMgGaO₄ strongly suggesting the survival of the quantum spin liquid state.

O-137 Salpingectomy versus neosalpingostomy in women with hydrosalpinx: a prospective cohort study with long-term follow-up

Study question

What is the comparative effectiveness between salpingectomy and neosalpingostomy in the treatment of bilateral severe hydrosalpinx?

Summary answer

In women with bilateral severe hydrosalpinx, salpingectomy combined with In Vitro Fertilization (IVF) treatment resulted in a higher cumulative live birth rate than neosalpingostomy.

What is known already

Hydrosalpinx accounts for 25% to 35% of female subfertility and has a negative effect on pregnancy rates in women who undergo IVF. So far salpingectomy before in vitro fertilization treatment has been suggested for the treatment of hydrosalpinx in order to improve the chance of a live birth. Previous studies have reported a pooled live birth rate of 25% through natural conception after neosalpingostomy and an ongoing pregnancy rate of 55.8% after salpingectomy with IVF. Direct comparison of the cumulative live birth rate after salpingectomy versus neosalpingostomy, both followed by IVF is lacking.

Study design, size, duration

We performed a single center, prospective comparative cohort study in the International Peace Maternity and Child Health Hospital affiliated to Shanghai Jiao Tong University School of Medicine, China. We studied women diagnosed with tubal subfertility with bilateral hydrosalpinx between January 2005 and December 2012. Based on a shared decision approach, they had bilateral salpingectomy or neosalpingostomy followed by IVF. They were annually followed up until July 2020 for the occurrence of live birth.

Participants/materials, setting, methods

Out of 113 women, 55 had bilateral salpingectomy and 58 had bilateral neosalpingostomy. Primary outcome was cumulative live birth rate, defined as the cumulative birth rate of the first living neonate through either natural conception or in vitro fertilization. Both intention-to-treat (ITT) and per-protocol (PP) analysis were processed. Cox proportional hazards regression model with potential variables was performed to identify predictors of successful live birth.

Main results and the role of chance

Baseline characteristics were comparable between two groups. There were 42 live births in the salpingectomy and 36 in the neosalpingostomy group. When the result of IVF was incorporated (55/55 in salpingectomy group and 25/58 in neosalpingostomy group underwent IVF), salpingectomy resulted in a higher cumulative live birth rate (85.3% vs 76.0%; hazard ratio of the whole survival curve, 2.18; 95% CI, 1.37 - 3.45; P = 0.001), a lower risk of ectopic pregnancy (1.8% vs 20.7%; risk ratio, 0.07; 95% CI, 0.01 - 0.57; P = 0.013), and a shorter time to live birth (19 [14,27] versus 36 [17,76] months, P = 0.001).The number of live birth rates after natural conception was 0% (0/55) in the salpingectomy group and 28% (16/58) in neosalpingostomy group.The results of PP analyses were comparable with the ITT analyses apart from the biochemical pregnancy rate and the overall live birth rate, they were higher (the former: 76% (42/55) versus 58% (29/50), P = 0.045; the latter: 76% (42/55) versus 56% (28/50), P = 0.027) in salpingectomy group.

Limitations, reasons for caution

This is an observational study. The small sample size along with the data was obtained from a cohort study in a single center.

Wider implications of the findings

In women with confirmed bilateral severe hydrosalpinx, salpingectomy followed by IVF results in a higher cumulative live birth rate and decreases the risk of EP as compared to neosalpingostomy. However, neosalpingostomy is the only option to achieve a live birth by natural conception that should be discussed with patients preoperatively.

Trial registration number

not applicable

Light Dark Matter Search with a High-Resolution Athermal Phonon Detector Operated above Ground

We present limits on spin-independent dark matter-nucleon interactions using a 10.6 g Si athermal phonon detector with a baseline energy resolution of σ_{E}=3.86±0.04(stat)_{-0.00}^{+0.19}(syst)  eV. This exclusion analysis sets the most stringent dark matter-nucleon scattering cross-section limits achieved by a cryogenic detector for dark matter particle masses from 93 to 140  MeV/c^{2}, with a raw exposure of 9.9 g d acquired at an above-ground facility. This work illustrates the scientific potential of detectors with athermal phonon sensors with eV-scale energy resolution for future dark matter searches.

Time resolved absolute extreme ultraviolet radiation measurement on the ENN XuanLong-50 spherical tokamak

A plasma radiation measurement system for a wide spectral range, based on compact Absolute eXtreme UltraViolet (AXUV) silicon photodiodes, has been implemented on the newly constructed ENN XuanLong-50 (EXL-50) spherical tokamak. The system consists of two 16-channel AXUV16ELG arrays and one AXUV63HS1 single-cell detector mounted on ceramic sockets. The two arrays, facing toward the EXL-50 slim central post from two locations inside a top and a side ConFlat 400 port, have 32 view chords covering the interested plasma region in a poloidal cross section at toroidal 330°. The single-cell detector, seated on a retractable feedthrough, could be arranged flexibly with the help of an ultra-high vacuum compatible gate valve. The design details together with considerations on the EXL-50 specific engineering realities and physics requirements are described. Preliminary results from the EXL-50 2020 experimental campaign are presented.

The 14-3-3 proteins: regulators of plant metabolism and stress responses

The 14-3-3 proteins bind to and modulate the activity of phosphorylated proteins that regulate a variety of metabolic processes in plants. Over the past decade interest in the plant 14-3-3 field has increased dramatically, mainly due to the vast number of mechanisms by which 14-3-3 proteins regulate metabolism. As this field develops, it is essential to understand the role of these proteins in metabolic and stress responses. This review summarizes current knowledge about 14-3-3 proteins in plants, including their molecular structure and function, regulatory mechanism and roles in carbon and nitrogen metabolism and stress responses. We begin with a molecular structural analysis of 14-3-3 proteins, which describes the basic principles of 14-3-3 function, and then discuss the regulatory mechanisms and roles in carbon and nitrogen metabolism of 14-3-3 proteins. We conclude with a summary of the 14-3-3 response to biotic stress and abiotic stress.

MiR-145-5p promotes myocardial cell apoptosis in rats with myocardial infarction through PI3K/Akt signaling pathway

OBJECTIVE

The aim of this study was to explore the influence of micro ribonucleic acid (miR)-145-5p on myocardial cell apoptosis in rats with myocardial infarction (MI) through the phosphatidylinositol 3-hydroxy kinase/protein kinase B (PI3K/Akt) pathway.

MATERIALS AND METHODS

In this study, Sprague-Dawley rats were used as research objects to establish the acute MI model in vivo. Infarction tissues and non-infarction tissues were both collected from rats. The expression level of miR-145-5p was determined using quantitative Polymerase Chain Reaction (qPCR), and the pathological changes in myocardial tissues of rats were observed through hematoxylin-eosin (HE) staining. In addition, H9c2 rat myocardial cells were cultured under hypoxia or normal oxygen concentration to simulate hypoxia in MI tissues. The changes in the expression of miR-145-5p in H9c2 cells in normal oxygen and hypoxia were determined. Meanwhile, the ratio of apoptotic cells to viable cells, and the changes in the expressions of proteins B-cell lymphoma 2 (Bcl-2), Bcl-2 associated X protein (Bax), Caspase-3 and Caspase-9 were evaluated through flow cytometry assay and Western blotting, respectively. The expression levels of crucial proteins in the PI3K/Akt pathway were measured as well. Additionally, H9c2 cells were transfected with miR-145-5p control and miR-145-5p mimic to evaluate cell apoptosis.

RESULTS

QPCR results revealed that the expression level of miR-145-5p was substantially elevated in MI tissues (p<0.05). HE results indicated that the soma exhibited deformation after MI, suggesting that there were more necrotic and apoptotic cells. Compared with those cultured under normal oxygen concentration, H9c2 cells cultured in hypoxia environment exhibited significantly upregulated expression level of miR-145-5p, downregulated expression level of anti-apoptosis protein Bcl-2, upregulated level of pro-apoptosis protein Bax, activated Caspase-3 and Caspase-9, and downregulated expression level of functional proteins in the PI3K/Akt pathway (p<0.05). Furthermore, the expression levels of apoptosis-associated proteins significantly rose in H9c2 cells transfected with miR-145-5p mimic compared with those transfected with miR-145-5p control, showing statistically significant differences (p<0.05).

CONCLUSIONS

MiR-145-5p is notably raised in MI tissues of rats. After infarction, there are evidently more apoptotic myocardial cells. The expression of miR-145-5p is markedly elevated in H9c2 rat myocardial cells in hypoxia. Compared with those cultured in normal oxygen, H9c2 cells cultured in hypoxia showed increased apoptosis. The apoptosis of myocardial cells transfected with miR-145-5p mimic is notable higher than that of myocardial cells transfected with miR-145-5p control. Moreover, the expressions of active Akt and PI3K proteins decrease remarkably. The results of this study demonstrate that miR-145-5p inactivates the PI3K/Akt pathway to promote the apoptosis of MI cells.

The influence of oncolytic reovirus on the biological activities of umbilical cord-derived mesenchymal stem cells

OBJECTIVE

To investigate the influence of oncolytic reovirus on the biological activities of human umbilical cord-derived mesenchymal stem cells (hUC-MSCs) as a novel virotherapy strategy.

MATERIALS AND METHODS

The Cell Counting Kit-8 assay was used to detect the viability of hUC-MSCs infected with different multiplicities of infection (MOIs) of reoviruses. The biological activities (proliferation, marker expression, multipotency, and migration) of hUC-MSCs were verified by assaying osteogenic and adipogenic differentiation potential, flow cytometry, and electrical cell-substrate impedance sensing, respectively.

RESULTS

The viability of hUC-MSCs slightly decreased by infection with low titers of reoviruses. A MOI of 1 had no effect on the viability of hUC-MSCs within 96 h. The biological activities (proliferation, marker expression, multipotency, and migration) of hUC-MSCs were not affected by reovirus infection at a MOI of 1.

CONCLUSIONS

Reovirus at a MOI of 1 had no effect on the biological activities of hUC-MSCs.

Changes of anti-β2 glycoprotein I antibody IgA/G/M, platelet aggregation rate, plasma fibrinogen and d-dimer in guiding venous thrombosis during pregnancy

OBJECTIVE

This study provides a theoretical basis for the prevention, treatment and diagnosis of venous thrombosis during pregnancy.

PATIENTS AND METHODS

Sixty patients with venous thrombosis in gestation period were treated as the research group, including every 30 people in the middle and late pregnancy groups, and the control group randomly selected 33 healthy pregnant women during the same period. The anti-β2 glycoprotein I antibody IgA/G/M, platelet aggregation rate, plasma fibrinogen, and D-dimer levels were measured in all subjects.

RESULTS

Resistance-β2 glycoprotein I antibody IgA/G/M, platelet aggregation rate, plasma fibrinogen, and compared with the control group, D-dimer levels were significantly increased (p<0.05), but for the middle pregnancy group and late pregnancy group, the difference was not statistically significant (p>0.05). In the control group of pregnant women anti-β2 glycoprotein Ⅰ antibody IgA/G/M, platelet aggregation rate, plasma fibrinogen, and D-dimer no obvious correlation (p>0.05), Anti-β2 glycoprotein Ⅰ antibody IgA/G/M, platelet aggregation rate, plasma fibrinogen, D-dimer entry equation are closely related risk factors for venous thrombosis during pregnancy (p<0.05), and D-dimer is the most important.

CONCLUSIONS

Vein thrombosis during pregnancy patients anti-β2 glycoprotein I antibody IgA/G/M, platelet aggregation rate, plasma fibrinogen, and D-dimer in pregnant women group increased significantly compared with the control group, suggesting these above indicators are closely related to Venous thrombosis in pregnant women and associated with the severity of the disease. Vascular endothelial injury plays an important role in phlebothrombosis in gestation period.

CDMP1 promotes type II collagen and aggrecan synthesis of nucleus pulposus cell via the mediation of ALK6

OBJECTIVE

Destruction of extracellular matrix (ECM), especially collagen II and aggrecan, is an essential feature of intervertebral disc degeneration (IDD). This project planned to elucidate the role of cartilage-derived morphogenetic protein-1 (CDMP-1) in the collagen II and aggrecan synthesis of nucleus pulposus (NP) cells under the IL-1β induced degeneration.

PATIENTS AND METHODS

We cultured human primary NP cells in the different concentrations of IL-1β medium and analyzed the CDMP-1 level. Recombinant human CDMP-1 protein was used to co-culture with IL-1β to investigate its effects on collagen II and aggrecan synthesis of NP cells. Additionally, the bone morphogenetic protein type IB receptor (ALK6) gene silenced and upregulated NP cells were used to evaluate the function of ALK6 in the CDMP-1 treated NP cells. Collagen II, aggrecan, MMP9, MMP13, and TIMP4 expression level were analyzed to assess the ECM stability of NP cells.

RESULTS

CDMP-1 gene expression decreased in the IL-1β treated NP cells with a dose-dependent. Appropriate CDMP-1 protein supplement contributed to the collagen II and aggrecan production, the suppression of MMP9 and MMP13, and the upregulation of TIMP4. However, the silencing of ALK6 rejected the positive function of CDMP-1 on the collagen II and aggrecan; on the contrary, ALK6 upregulation magnified the CDMP-1 induced collagen II and aggrecan production.

CONCLUSIONS

CDMP-1 is efficient in promoting the collagen II and aggrecan synthesis of NP cells, which is probably based on the mediation of ALK6.

[Analysis of capability to pertussis etiology and serological diagnosis for GradeⅡ and Ⅲmedical institutions in Shandong Province in 2018]

Objective: Investigate and analyze the etiology and serological diagnosis capabilities of pertussis in medical institutions in Shandong Province in 2018. Methods: Using the census method, a questionnaire survey was conducted among 603 second and above level medical institutions in Shandong Province. The deadline for the survey was December 2018, and a total of 543 questionnaires have been recovered, and the validity rate of the questionnaires was 90%. Surveyed the pertussis etiology and serology test items (pertussis IgM and IgG, pertussis nucleic acid and pertussis bacterial culture) and the start time of each test item by questionnaire. The reported cases (confirmed cases and clinically diagnosed cases) between January 1, 2012 and December 31, 2018 were derived from the Chinese Disease Control and Prevention Information System according to the onset date. We used indicators such as fixed-base development speed, chain development speed, and chain growth speed for analysis. The chi test was used to analyze the differences in the composition ratio of medical institutions with detection ability in different levels and regions, and analyze the changes in the number of reported cases before and after the development of pertussis etiology and serology testing. Results: A total of 543 medical institutions accounted for 90.0% (543/603) of all secondary and above level medical institutions in the province, 356 secondary medical institutions (65.6%), and 187 tertiary medical institutions (34.4%). There were 10 medical institutions that carry out pertussis IgM, IgG and nucleic acid testing, accounting for 1.8% (10/543) of the surveyed medical institutions respectively. 2 medical institutions that carried out bacterial culture, accounting for 0.4% of the surveyed medical institutions (2/543). 20 medical institutions have carried out the above tests (8 secondary medical institutions and 12 tertiary medical institutions), accounting for 3.7% (20/543). The proportion of tertiary medical institutions with pertussis IgM, IgG detection and nucleic acid detection capabilities [6.42% (12/187)] was significantly higher than that of secondary medical institutions [2.25% (8/356)] (χ²=6.01, P=0.014). From 2012 to 2018, the fixed base ratio development speed of reported cases was 3 834.69% in Shandong Province, among which medical institutions with etiology and serological testing capabilities reached 4 533.33%. In 13 medical institutions, the average annual number of reported cases after pertussis etiology and serological testing were higher than that of reported cases before testing. Conclusion: The ability of pertussis etiology and serology diagnosis of secondary and above medical institutions in Shandong Province needs to be improved.

[Gender differences in risk factors and characteristics of young patients hospitalized for first acute coronary syndrome]

Objective: To analyze the characteristics of modifiable risk factors, coronary artery lesions, reperfusion and drug treatment in young women hospitalized for first acute coronary syndrome (ACS). Methods: Clinical data of young adults of 18 to 44 years hospitalized for first ACS in Beijing Anzhen Hospital between January 2007 and December 2017 were analyzed. A total of 7 106 young adults with ACS were enrolled, 6 593(92.8%) were male and 513(7.2%) were female. There were 2 254(31.7%) patients with ST-segment elevation myocardial infarction (STEMI), 704(9.9%) patients with non-ST-segment elevation myocardial infarction (NSTEMI) and 4 148(58.4%) patients with unstable angina (UA). Clinical characteristics, laboratory examinations, coronary angiography and medical treatment were recorded. The gender differences in the characteristics of modifiable risk factors and coronary artery stenosis in young patients with ACS were also analyzed. Results: Dyslipidemia (87.5%) followed by overweight/obese(83.8%) and smoking (68.5%) were most prevalent modifiable risk factors in men. Dyslipidemia (63.4%), overweight/obese (63.4%) and hypertension (45.5%) were most prevalent modifiable risk factors in women. The prevalence rates of at least 1 risk factor in men and women patients were 99.1% and 87.9%, respectively. Between 2007 and 2017, the rates of hypertension and overweight/obese in men increased, and the rates of dyslipidemia and smoking decreased (trend P<0.01). The changes of incidence of modifiable risk factors through the years in women were not statistically significant. The rate of men receiving coronary angiography was higher than that in women (96.6% vs 93.4%, P<0.01). Women were more likely to suffer left main coronary artery disease than men (7.3% vs 4.1%, P<0.01). Multi-vessel coronary artery disease occurred more in men (43.4%), and single vessel coronary artery disease occurred more in women (47.0%). Women presented with STEMI had a lower probability of receiving clopidogrel/ticagrelor (76.8% vs 86.1%, P<0.01) and angiotensin Ⅰ-converting enzyme inhibitor/angiotonin receptor blocker (ACEI/ARB) (46.5% vs 60.2%, P<0.01) than that in men. Women presented with UA had a lower probability of receiving aspirin (86.3% vs 89.9%), clopidogrel/ticagrelor (69.7% vs 75.6%), statin (78.8% vs 85.0%) and ACEI/ARB (32.7% vs 38.6%) than men (all P<0.01). Women had a higher probability of presenting Killip II-IV than men (38.6% vs 25.6%, P<0.05). Conclusion: The majority of young patients with ACS were men. The prevalence rates of modifiable risk factors are very high in both man and woman. Compared with man, women with AMI are more likely to develop acute heart failure with lower probability of reperfusion and drug treatment.

Toroidal soft x-ray array on the EXL-50 spherical tokamak

A toroidal soft x-ray array system for spectrum and intensity measurements on the EXL-50 spherical tokamak is described. Silicon drift detectors and digital multichannel analyzers are adopted for all 21 channels of the array, and an average energy resolution of 147 eV at 5.89 keV has been achieved at count rates over 500 kcps. In total, 20 channels of the array are symmetrically observed in both co- and counter-current directions on the EXL-50 mid-plane with a spatial resolution of around 10 cm, and the remaining one serves as a background reference channel. Tungsten emissions from tungsten coating of the limiters on the central post are observed. The influence of hard x rays on measured soft x-ray spectra and system operation is discussed.

Linc00601 upregulation promotes hepatocellular carcinoma development by activating MAPK signaling pathway

OBJECTIVE

To study the expression of linc00601 in hepatocellular carcinoma (HCC) tissues and cells, and to study the biological function and downstream mechanism of linc00601 in HCC using in vitro experiments.

PATIENTS AND METHODS

The expression of linc00601 in HCC was predicted via bioinformatics, and the expression of linc00601 in HCC tissues and cells was detected via quantitative Reverse Transcription-Polymerase Chain Reaction (qRT-PCR). After interference with the expression of linc00601, the interference efficiency was determined using qRT-PCR, and the changes in HCC cell proliferation, cycle distribution, and apoptosis were determined through Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. Finally, the expressions of molecular markers in downstream signaling pathway were determined through Western blotting.

RESULTS

It was found via bioinformatics that the expression of linc00601 was upregulated in HCC. The results of qRT-PCR revealed that the expression of linc00601 was upregulated in 36 cases of HCC tissues compared with that in para-carcinoma tissues, and it was also upregulated in HCC cells. According to the results of CCK-8 assay, HCC cell proliferation was inhibited after interference with the expression of linc00601. In the si-linc00601 group, the apoptosis rate rose, and the cell cycle was arrested at the G1/G0 phase compared with those in the si-NC group. The results of Western blotting revealed that after the knockdown of linc00601 in HCC cells, the expressions of molecular markers (p-P38, p-ERK) in the downstream mitogen-activated protein kinase (MAPK) signaling pathway were downregulated.

CONCLUSIONS

Linc00601 is upregulated in HCC, which promotes the development of HCC via activating the MAPK signaling pathway.

A pan-HER-targeted approach for recurrent or late-stage cervical cancer therapy: mechanisms, recent advances, and clinical prospects

OBJECTIVE

Over-expression of the epidermal growth factor receptor (EGFR) protein, along with gene amplification, is closely associated with recurrent cervical cancer and the disease's advanced stages. Additionally, it can have a direct impact on the disease's prognosis. The following are the members of the HER family: (i) EGFR/HER1; (ii) HER2; (iii) HER3; and (iv) HER4. Figure 1 shows its signalling pathway. The synergy between the members facilitates immune escape by tumour cells, which can lead to tolerance to HER inhibitors. A broad HER inhibitor, a pan-HER inhibitor, can irreversibly inhibit a cell membrane's HER receptors to their ligands, thereby blocking downstream signal-transduction cascades, inhibiting tumour growth, adhesion, invasion, differentiation, and metastasis. As such, pan-HER inhibitors may be an area of interest in treating recurrent or late-stage cervical cancer.

MATERIALS AND METHODS

Through a review of HER-family receptors and their molecular mechanism, we can conclude that pan-HER inhibitors do indeed have a positive impact on therapy for recurrent or late-stage cervical cancer patients.

RESULTS

This paper reviews the molecular mechanism that underlies receptors within the HER family, current developments in HER inhibitors, and the potential clinical impacts of pan-HER inhibitors in treating recurrent or late-stage cervical cancer.

CONCLUSIONS

Pan-HER inhibitors have been shown to improve prognoses for recurrent or late-stage cervical cancer patients. Preclinical studies show promising results, as well as the potential to improve results for recurrent or late-stage cervical cancer patients. Pan-HER inhibitors have also shown synergistic results in clinical and pre-clinical settings when combined with chemotherapy. However, long-term study is required regarding the combination of pan-HER inhibitors with radiotherapy and other targeted inhibitors. The question of whether or not these inhibitors have a more potent effect across the blood-brain barrier when compared to single HER-targeting agents may be an area of interest for future research. This idea will be explored in clinical cervical cancer trials.

METTL3 promotes the progression of nasopharyngeal carcinoma through mediating M6A modification of EZH2

OBJECTIVE

The aim of this study was to investigate whether METTL3 promoted the progression of nasopharyngeal carcinoma (NPC) by silencing CDKN1C through EZH2.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine the expression level of METTL3 in 48 pairs of NPC tissues and adjacent normal tissues. METTL3 expression in patients with different tumor lymph node metastasis (TNM) stages was detected by qRT-PCR as well. The Kaplan-Meier method was used to analyze the interplay between METTL3 expression and the prognosis of patients with NPC. At the same time, METTL3 expression in normal epithelial cell line (BEAS-2B) and NPC cell lines (SUNE-1 and C666-1) was examined using qRT-PCR. After METTL3 was knocked down in SUNE-1 cells, cell viability and migration abilities were analyzed by cell counting kit-8 (CCK-8) test and wound healing assay, respectively. The mRNA and protein expressions of EZH2 were detected by qRT-PCR and Western blot, respectively. RNA immunoprecipitation (RIP) assay was applied to detect the binding of METTL3 to EZH2 mRNA and the m6A modification on EZH2 mRNA. After knockdown of EZH2 in SUNE-1 cells, qRT-PCR was used to detect the mRNA expression of CDKN1C. Meanwhile, chromatin immunoprecipitation (ChIP) assay was conducted to analyze the binding of EZH2 to the CDKN1C promoter region. After down-regulation of METTL3 in SUNE-1 cells, the protein expressions of EZH2 and CDKN1C were detected using Western blot. After simultaneous knockdown of METTL3 and CDKN1C in SUNE-1 cells, CCK8 assay and wound healing assay were applied to examine cell viability and migration abilities.

RESULTS

METTL3 expression in NPC tissues was remarkably higher than that of adjacent normal tissues. Meanwhile, METTL3 expression in T3 and T4 tumors was significantly higher than that of T1 and T2 tumors. In patients with lymph node metastasis, the expression of METTL3 was remarkably higher than those without metastasis. Survival analysis demonstrated that patients with higher expression of METTL3 exhibited significantly longer overall survival time than those with lower METTL3 expression. QRT-PCR revealed that METTL3 was highly expressed in NPC cell lines, including SUNE-1 and C666-1. After knock-down of METTL3 in SUNE-1 cells, cell viability and migration abilities were both markedly weakened. Meanwhile, the protein expression of EZH2 was remarkably reduced. However, no significant changes were observed in EZH2 mRNA level. RIP assay revealed that METTL3 could bind to EZH2 mRNA, and a m6A modification was verified on EZH2 mRNA. After knockdown of EZH2, the mRNA level of CDKN1C in SUNE-1 cells was significantly up-regulated. CHIP assay indicated that EZH2 could bind to CDKN1C. Western blot showed that, after interfering with METTL3 in SUNE-1 cells, the protein expression of EZH2 decreased significantly, while CDKN1C was up-regulated. In addition, simultaneous downregulation of METTL3 and CDKN1C in SUNE-1 cells reversed the influence of METTL3 on cell viability and migration abilities.

CONCLUSIONS

METTL3 was highly expressed in NPC tissues, which might inhibit EZH2 expression by mediating M6A modification of EZH2 mRNA. Furthermore, CDKN1C could increase the malignancy of NPC cells and promote the progression of NPC.

Impact of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on the outcomes in patients with refractory lung cancer

Background

PD-1/PD-L1 inhibitors in combination with chemotherapy are widely used in clinical practice. However, the ideal combined timing of them has not been fully explored.

Methods

In this study, simulation experiments to explore the impacts of the combination of anti-PD-1 antibody (anti-PD-1 Ab) on the cytotoxic effects of chemotherapeutic drugs in peripheral blood mononuclear cells were performed. In addition, the effects of the combined timing of PD-1/PD-L1 inhibitors and chemotherapy on efficacy and safety were retrospectively analysed in patients with refractory lung cancer.

Results

Experiments in vitro showed that administering the anti-PD-1 Ab 3 days after chemotherapy (represented by dicycloplatin) resulted in significantly weaker cytotoxic effects on lymphocytes, compared with administering the anti-PD-1 Ab before or concurrent with chemotherapy. Moreover, data from 64 lung cancer patients treated with PD-1/PD-L1 inhibitors plus chemotherapy as a second- or higher-line therapy were retrospectively analysed. The results showed that administering PD-1/PD-L1 inhibitors 1-10 days (especially 3-5 days) after chemotherapy was associated with longer overall survival [17.3 months versus 12.7 months; hazard ratio (HR) = 0.58, 95% confidence interval (CI) 0.28-1.19, P = 0.137 in univariate analysis; HR = 0.36, 95% CI 0.16-0.80, P = 0.012 in multivariate analysis] and a trend of improved progression-free survival (5.1 months versus 4.2 months; HR = 0.81, 95% CI 0.42-1.54, P = 0.512) compared with administering PD-1/PD-L1 inhibitors before or concurrent with chemotherapy.

Conclusion

Our findings suggest that administering PD-1/PD-L1 inhibitors 1-10 days (especially 3-5 days) after chemotherapy is superior to administering PD-1/PD-L1 inhibitors before or concurrent with chemotherapy in patients with refractory lung cancer, but this result needs to be further explored by prospective studies.

•

The cytotoxic effects of chemotherapeutic drugs were positively correlated with the activation states of PBMCs.

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Administering the anti-PD-1 Ab 3 days after chemotherapy resulted in weaker cytotoxic effects on lymphocytes in vitro.

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Administering PD-1/PD-L1 inhibitors a few days after chemotherapy resulted in better survival in lung cancer patients.

[Risk factor distribution features and trends of young adults with first acute coronary syndrome]

Objective: To observe the characteristics and trends during the last 11 years of risk factors of young adults with first acute coronary syndrome (ACS). Methods: It was a cross-sectional study. We included young adults (18 to 44 years old) hospitalized for acute coronary syndrome in Beijing Anzhen Hospital for a first time from January 2007 to December 2017. Acute coronary syndromes include ST-elevation myocardial infarction (STEMI), non-ST-elevation myocardial infarction (NSTEMI), and unstable angina (UA). The general information, medical history and laboratory test were recorded. Risk factors of ACS were smoking, dyslipidemia, overweight/obesity, hypertension and diabetes. Results: Data from 7 106 patients were analyzed, mean age was (39.8±4.2) years old and 6 593(92.8%)were men, including 2 254 (31.7%) STEMI, 704 (9.9%) NSTEMI and 4 148 (58.4%) UA. Most patients were male (6 593(92.8%)). Dyslipidemia (85.8%(6 094/7 106)), overweight/obesity (82.3%(5 850/7 106)), and smoking (63.9%(4 545/7 106)) were most prevalent. 98.3% (6 885/7 106) patients had at least 1 risk factor. The prevalence of hypertension, diabetes and overweight/obesity increased from 2007 to 2017. Rates of hypertension increased from 37.1%(111/299) to 48.1%(498/1 035) (Ptrend<0.01), diabetes from 12.0%(36/299) to 19.4%(201/1 035) (Ptrend<0.01), overweight/obesity from 74.2%(222/299) to 83.9%(868/1 035) (Ptrend<0.05), respectively. Conclusions: Dyslipidemia, overweight/obesity and smoking are most prevalent risk factors in young adults with a first ACS and most patients have at least 1 risk factor for ACS. Rates of hypertension, diabetes and overweight/obesity progressively increases over time in this patient cohort.

XTP8 stimulates migration and invasion of gastric carcinoma through interacting with TGIF1

OBJECTIVE

To determine expression characteristics of XTP8 and TGIF1 in gastric carcinoma (GC), and the potential roles of XTP8/TGIF1 axis in influencing the progression of GC.

MATERIALS AND METHODS

The expression levels of XTP8 and TGIF1 in GC tissues and cells were detected. Their functions in prognosis in GC patients were evaluated by the Kaplan-Meier method. The correlation between the XTP8 level and the pathological indexes of the GC patients were analyzed. The changes in the proliferation, migration, and invasion capacities of MKN-45 and SGC-7901 cells affected by XTP8 and TGIF1 were assessed. The interaction between XTP8 and TGIF1 was determined through Dual-Luciferase reporter gene assay and rescue experiments.

RESULTS

XTP8 was upregulated in GC tissues and cells. XTP8 level was positively correlated with lymphatic and distant metastasis, as well as poor prognosis of GC patients. The silence of XTP8 attenuated proliferation, migration, and invasion capacities of MKN-45 and SGC-7901 cells. TGIF1 was the downstream gene binding to XTP8, which was downregulated in GC, and XTP8 negatively regulated the TGIF1 level in GC tissues. Importantly, the knockdown of TGIF1 could abolish the regulatory effect of XTP8 on GC cell behaviors.

CONCLUSIONS

XTP8 is upregulated in GC and is closely linked to lymphatic metastasis, distant metastasis, and poor prognosis of GC patients. Besides, it accelerates the malignant progression via negatively regulating TGIF1.

A205 PEMBROLIZUMAB ASSOCIATED SCLEROSING CHOLANGITIS RESPONDS TO COMBINATION OF STEROIDS AND MYCOPHENOLIC ACID: A CASE REPORT

Background

Pembrolizumab is a check point inhibitor that targets programmed cell death receptor ligand 1 (PD-L1). However, check-point inhibitors are associated with its characteristic adverse event know as immune related adverse events that can affect a myriad of organ systems. In the hepatobiliary system, the most commonly described iRAE is hepatitis/hepatotoxicity and latest oncology guidelines offer recommendations on treatment and followup of immunotherapy related hepatitis (1). However, a more rare presentation of iRAE, that have only been described as case reports or case series, is secondary cholangitis. We report one of such a case.

Aims

Case report

Methods

Case report

Results

The patient is a 55 year-old Caucasian female know for lung adenocarcinoma presented to the emergency room on May 5th, 2020, having received her 8th cycle of pembrolizumab. Her blood works mildly elevated transaminitis; ALT 78 U/L, AST 11 U/L, alkaline phosphate of 130 U/L, and total bilirubin of 3.5 umol/L.

MRI of the abdomen showed a normal appearing liver without focal parenchymal lesion, no biliary stones or obstructing masses, dilated common bile duct at 11 mm with small pericholecystic free fluid, and normal gall badder thickness of 2 mm. There was also notion of minimally prominent intrahepatic biliary radicles seen within the CBD.

Etiology workup of cholestatic transaminitis was negative. A diagnosis of immunotherapy related sclerosing cholangitis was posed and the patient was treated with MMF and prednisone with good response.

Conclusions

Discussion

This patient seems to have developed immunotherapy mediated cholangitis. Liver biopsy when performed in liver injury tend to show lobular hepatitis, with liver parenchyma infiltrated with lymphocytes and focal necrosis with acidophilic bodies. However, there seems to be another, less frequent pattern of injury described with pembrolizumab and associated with cholangiopathy, resembling primary biliary cholangitis. It is characterized with portal tracts enlarged with fibrosis and inflammatory cells infiltration; infiltrating cells are lymphocytes (2). Biliary epithelium with fibrosis with CD8+ T cells infiltration seem to be recurrently reported in case reports. (3, 4).

Other cases have been describe in the literature. In many cases, steroid therapy was attempted, but response rates seem to be inconsistent. Nivolumab related cholangitis have been also been described and characterized by extra hepatic bile duct dilatation along with negative immunological markers such as ANA and IgG4 in patients with non-small cell lung cancer, and seems to respond only moderately to steroid therapy (6). Retrospective data of nivolumab related cholangiopathy seems to suggest that there is favourable response to the combination of MMF and steroid therapy (7).

Funding Agencies

None

Phase-field-simplified lattice Boltzmann method for modeling solid-liquid phase change

This article proposes a phase-field-simplified lattice Boltzmann method (PF-SLBM) for modeling solid-liquid phase change problems within a pure material. The PF-SLBM consolidates the simplified lattice Boltzmann method (SLBM) as the flow solver and the phase-field method as the interface tracking algorithm. Compared with conventional lattice Boltzmann modelings, the SLBM shows advantages in memory cost, boundary treatment, and numerical stability, and thus is more suitable for the present topic which includes complex flow patterns and fluid-solid boundaries. In contrast to the sharp interface approach, the phase-field method utilized in this work represents a diffuse interface strategy and is more flexible in describing complicated fluid-solid interfaces. Through abundant benchmark tests, comprehensive validations of the accuracy, stability, and boundary treatment of the proposed PF-SLBM are carried out. The method is then applied to the simulations of partially melted or frozen cavities, which sheds light on the potential of the PF-SLBM in resolving practical problems.

Adverse cardiovascular ageing among older women and cardiometabolic ageing

Funding Acknowledgements

Type of funding sources: Public hospital(s). Main funding source(s): National Medical Research Council (NMRC)

Background

Despite longer life expectancies, women may experience reduced ‘health-span’ (period of life spent in good health) due to accumulation of risks over their longer life spans. Metabolic factors present in diet and lifestyle may provide modifiable solutions to tackle burdens of cardiovascular (CV) ageing in women.

Objective

We aim to study gender differences in CV structure and function among community older adults without clinical CV disease, as well as metabolic perturbations in their study samples.

Methods

We examined a prospective cohort study of older adults, obtaining their medical history, serum sampling, echocardiography and cardiac magnetic resonance (CMR) imaging on a single day visit. Echo E/A ratio was computed as a ratio of peak velocity flow in early diastole E (m/s) to peak velocity flow in late diastole by atrial contraction A (m/s) mitral inflow velocities. Longitudinal strain (ε) at any time point (t) in the cardiac cycle from end-diastole (time 0) was calculated as: ε(t)=(L(t)-L0)/L0, obtaining left atrial (LA) reservoir strain (εs), conduit strain (εe) and booster strain (εa) by CMR. Metabolomics profiling was performed by standard mass spectrometry techniques.

Results

Among n = 492 (49.6%, n = 244 women, mean age 73 ± 4 years) participants, women had lower prevalence of hypertension (52% vs 58%, p &lt; 0.0001), smoking (4% vs 35%, p &lt; 0.0001), but higher prevalence of dyslipidemia (52% vs 50%, p = 0.001) compared to men. Women had lower left ventricular mass index (69 vs 71 g/m2, p &lt; 0.0001) compared to men. However, women had more adverse CV function, such as lower E/A ratio (0.78 vs 0.85, p &lt; 0.0001), lower LA booster (εa) (16.5 vs 17.8, p = 0.027) and lower LA reservoir (εs) strain rate (1.5 vs 1.6, p = 0.012), compared to men. Amino acids such as alanine, arginine, aspartate, citrulline, glycine, phenylalanine and valine were similar between gender. However, women had higher levels of tyrosine (76 vs 68 μM, p = 0.015). On multivariate adjustment, apart from age, tyrosine was independently associated with E/A ratio (β=0.002, 95%CI 0.00-0.004, p = 0.044) and εs (β=0.004, 95%CI 0.00-0.009, p = 0.048) among women. 

Conclusion

Utilizing conventional and sensitive CV imaging, women appeared to have more adverse CV functions with ageing. As a branched chain amino acid linked to future risk of CV disease, tyrosine may be linked to adverse CV function. Factors that contribute to these cardiometabolic profiles, such as menopause, diet or lifestyle warrant further research.

Tunable interfacial Dzyaloshinskii-Moriya interaction in symmetrical Au/[Fe/Au]n multilayers

The interfacial Dzyaloshinskii-Moriya interaction (i-DMI) has been exploited in as-made symmetrical Au/[Fe/Au]n structures. By tailoring the chirality of the i-DMI at the Au/Fe interface, an overall enhancement of the i-DMI can be obtained in such a symmetrical structure. Furthermore, the tunability of the i-DMI was realized by changing the stacking number n. Compared to the top of Fe, a large tensile stress at the bottom of Fe due to lattice mismatch was responsible for the chirality change in the sub/Au/Fe system. Layer-resolved DMI calculations revealed that the sign of the spin-orbit coupling (SOC) energy was changed for Au near the interface of Au/Fe under tensile stress, subsequently reversing the chirality of the i-DMI from left-handed to right-handed. Our findings provide a simplest way to tune the i-DMI in a multilayer system, further benefiting the application of skyrmion-based devices.

Regulation of circadian behavioural output via clock-responsive miR-276b

Growing evidence indicates that microRNAs play numerous important roles. However, the roles of some microRNAs involved in regulation of circadian rhythm and sleep are still not well understood. In this study, we show that the miR-276b is essential for maintaining both sleep and circadian rhythm by targeting tim, npfr1 and DopR1 genes, with miR-276b deleted mutant flies sleeping more, and vice versa in miR-276b overexpressing flies. Through analysing its promoter, we found that mir-276b is responsive to CLOCK and regulates circadian rhythm through the negative feedback loop of the CLK/CYC-TIM/PER. Furthermore, miR-276b is broadly expressed in the clock neurons and the central complexes such as the mushroom body and the fan-shape body of Drosophila brain, in which up-regulation of miR-276b in tim, npfr1 and DopR1 expressing tissues significantly causes sleep decreases. This study clarifies that the mir-276b is very important for participating in regulation of circadian rhythm and sleep.

[Clinicopathological features of the colorectal serrated adenoma and analysis on influencing factors of malignancy]

Objective: Serrated adenoma is recognized as a precancerous lesion of colorectal cancer, and the serrated pathway is considered as an important pathway that can independently develop into colorectal cancer. However, little is known about the related risk factors of carcinogenesis of serrated adenoma. The purpose of this study was to analyze the distribution characteristics and potential malignant factors of serrated adenoma in the colon and rectum. Methods: A retrospective case-control study was conducted to collect the clinical data of patients with serrated adenoma who underwent colonoscopy and were pathologically diagnosed in the Cancer Hospital of Chinese Academy of Medical Sciences from April 2017 to July 2019, and exclude patients with two or more pathological types of lesions. The clinical characteristics of serrated adenoma were summarized, and univariate and logistic multivariate regression analysis was conducted to explore the influencing factors for serrated adenoma to develop malignant transformation. Results: Among 28 730 patients undergoing colonoscopy, 311 (1.08%) were found with 372 serrated adenomas, among which 22 (5.9%) were sessile serrated adenomas/polyps, 84 (22.6%) were traditional serrated adenomas, and 266 (71.5%) were unclassified serrated adenomas according to WHO classification. The pathological results showed that 106 (28.5%) lesions were non-dysplasia, 228 (61.3%) lesions were low grade intraepithelial neoplasia, and 38 (10.2%) lesions were high grade intraepithelial neoplasia or cancer. There were 204 (54.8%) lesions with long-axis diameter <10 mm and 168 (45.2%) lesions with length long-axis ≥ 10 mm. 238 (64.0%) lesions were found in the left side colon and rectum and 134 (36.0%) lesions in the right side colon. Gross classification under endoscopy: 16 flat type lesions (4.3%), 174 sessile lesions (46.8%), 117 semi-pedunculated lesions (31.5%), 59 pedunculated lesions (15.9%). Narrow-band imaging international colorectal endoscopic (NICE) classification: 85 (22.8%) type I lesions, 280 (75.3%) type II lesions, 4 (1.1%) type III lesions. Univariate analysis showed that lesion size, lesion location, lesion site and different WHO classifications were associated with malignant transformation of colorectal serrated adenoma (all P<0.05). For the serrated adenomas with different NICE classifications, there were statistically significant differences in the distribution of malignant lesions among groups (P=0.001). Multivariate analysis showed that the long-axis diameter of the lesion ≥10 mm (OR=6.699, 95% CI: 2.843-15.786) and the lesion locating in the left side colorectum (OR=2.657, 95% CI: 1.042-6.775) were independent risk factors for malignant transformation. Conclusions: Serrated adenomas mainly locate in the left side colon and rectum, and are prone to malignant transformation when the lesions are ≥10 mm in long-axis diameter or left-sided.

[Efficacy and safety of catheter ablation in patients with new-onset atrial arrhythmia after surgical excision of left atrial myxoma]

Objective: To evaluate the safety and efficacy of catheter ablation in patients with new-onset atrial arrhythmia after surgical excision of left atrial myxoma. Methods: Nine patients with new onset atrial arrhythmia and a prior history of left atrial myxoma, who received surgical myxoma excision and catheter ablation between September 2014 and November 2019, were included in the present study. Baseline characteristics, procedural parameters during catheter ablation, severe perioperative adverse events, recurrence rate of arrhythmia and clinical prognosis were analyzed. Kaplan Meier survival analysis was used to define the maintenance rate of sinus rhythm after catheter ablation in this patient cohort. Results: Nine patients were included. The average age was (55.8 ± 9.1) years old (3 male), there were 3 patients (3/9) with paroxysmal atrial fibrillation (PAF) and 6 patients (6/9) with atrial flutter or atrial tachycardia (AFL or AT). Ablation was successful in all patients, there were no perioperative complications such as stroke, pericardial effusion, cardiac tamponade, vascular complications or massive hemorrhage. During a mean follow-up time of 40.0 (27.5, 55.5) months, sinus rhythm was maintained in six patients (6/9) after the initial catheter ablation. The overall sinus rhythm maintenance rate was 2/3. In addition, 1 out of the 3 AF patients (1/3) developed recurrence of AF at 3 month after ablation, and 2 out of the 6 AFL or AT patients (2/6) developed late recurrence of AF or AFL (19 months and 29 months after ablation), two out of three patients with recurrent AFs or AFL received repeated catheter ablation and one patient remained sinus rhythm post repeat ablation. Meanwhile, there was no recurrence of atrial myxoma, no death, stroke, acute myocardial infarction and other events during the entire follow-up period. Conclusions: Catheter ablation is a safe and feasible therapeutic option for patients with new-onset atrial arrhythmia after surgical excision of left atrial myxoma.

Effects of Comorbidities on the Elderly Patients with COVID-19: Clinical Characteristics of Elderly Patients Infected with COVID-19 from Sichuan, China

OBJECTIVES

The co-occurrence of chronic diseases in the elderly is a common problem. However, the relationship between comorbidities and the prognosis of elderly patients with COVID-19 was not clear. This study was supposed to describe the clinical characteristics of elderly patients with COVID-19 infection from Sichuan province and the effects of comorbidity.

DESIGN

A retrospective study.

SETTINGS AND PARTICIPANTS

COVID-19 patients from Public Health Clinical Center of Chengdu between December 16, 2019 and February 26, 2020 were included in this study. Patients were divided into elderly group (≥60 years old) and non-elderly group (< 60 years old).

RESULTS

Elderly patients with COVID-19 indicated relatively higher proportion of comorbidities, and the most common were atherosclerotic cardiovascular disease (56.5%), hypertension (43.5%) and chronic pulmonary disease (21.7%). The proportion of severe cases was higher in elderly group than that in non-elderly group (73.9% and 42.2%, respectively, P=0.012). During hospitalization, elderly patients indicated relatively higher proportion of complications, such as shock (21.7%), respiratory failure (21.7%). The proportion of patients with a decreased number of CD8+ lymphocytes (82.6%) and B lymphocytes (77.8%) in elderly patients was significantly higher than that in non-elderly group (48.9% and 44.8%, respectively). All 3 deaths were elderly patients with comorbidities and the cell counts of T lymphocyte subsets, B and NK cells of them were significantly decreased at admission.

CONCLUSIONS

Elderly patients with COVID-19 had a high proportion of severe cases and comorbidities, more likely to show low immune function, and indicate higher proportion of complications.

The role of protein restriction and interaction with antibiotics in the regulation of compensatory growth in pigs: growth performance, serum hormone concentrations, and messenger RNA levels in component tissues of the endocrine growth axis

The present study investigated the effects of protein restriction and antibiotics on the hypothalamus-pituitary-liver growth axis during the compensatory growth of growing and finishing pigs. Growth performance, serum hormones, and messenger RNA (mRNA) levels of hormones and their receptors in growth axis tissues were recorded for analyses. A total of 64 piglets (large white × Landrace × Duroc cross) with an initial weight of 10.07 ± 0.14 kg were randomly divided into 4 treatment groups of 16 piglets per group. The dietary treatments consisted of 2 protein levels (14% and 20%) and 2 antibiotic levels (no antibiotics and 20 mg/kg colistin sulfate with 50 mg/kg kitasamycin) in a 2 × 2 factorial arrangement. The study was performed over 30 d for the first stage (S1, restriction phase) and 74 d for the second stage (S2, realimentation phase). The 4 treatment diets were maintained throughout the duration in the restriction phase. The 4 groups were fed the same diet in the realimentation phase. The trial period totaled 104 d. Protein restriction decreased BW, average daily food intake, and ADG in weaning pigs (P < 0.01) and induced compensatory growth after feeding a normal diet during the growth of finishing pigs. Average daily gain increased during the last phase of compensatory growth (P < 0.01). Protein restriction increased serum GH and leptin (LEP) and the mRNA levels of liver IGF-1 receptor (IGF-1-R; P < 0.01) but decreased serum IGF-1 (P < 0.01) and the mRNA levels of liver GH receptor (GH-R; P < 0.01) and IGF-1 (P < 0.05) in weaning piglets. Serum GH was increased, but serum IGF-1 was decreased during the realimentation phase (P < 0.05). Antibiotics increased the mRNA levels of GHRH (P < 0.05) and decreased somatostatin (P < 0.01) in the hypothalamus of weaning pigs. Protein restriction and antibiotics had no interactions across the entire trial. In conclusion, the slowing of growth caused by early protein restriction may be compensated for in the later stages of pig raising, and the mechanism of compensation is related to the regulation of GH, IGF-1, GH-R, and IGF-1-R.

Two fatty acid synthase genes from the integument contribute to cuticular hydrocarbon biosynthesis and cuticle permeability in Locusta migratoria

Lipids of the insect cuticle have important roles in resistance against the arid environment and invasion of foreign substances. Fatty acid synthase (FAS) is an important enzyme of the insect lipid synthesis pathway. In the present study, we identified three FAS genes from transcriptome data of the migratory locust, Locusta migratoria, based on bioinformatics analyses. Among them, two FAS genes (LmFAS1 and LmFAS3) are highly expressed in the integument of fifth instar nymphs. Suppression of LmFAS1 and LmFAS3 by RNA interference caused lethality during ecdysis or shortly after moulting. The weight of the locusts and the content of lipid droplets were reduced compared with those of the control. The results of gas chromatography-mass spectrometry analysis showed that knockdown of LmFAS3 led to a decrease of both cuticular hydrocarbons and inner hydrocarbons (CHCs and IHCs) contents, especially the content of methyl branched hydrocarbons. By contrast, knockdown of LmFAS1 only resulted in a decrease in the IHC content, but not that of CHCs. By consequence, in LmFAS1- and LmFAS3-suppressed locusts, hydrocarbon deficiency reduced desiccation resistance and enhanced cuticle permeability and sensitivity to insecticides. These results indicate that LmFAS1 and LmFAS3 are essential for hydrocarbon production and cuticle permeability, which play influential roles in waterproofing the insect cuticle.

Associations of ATG7 rs1375206 polymorphism and elevated plasma ATG7 levels with late-onset sporadic Parkinson's disease in a cohort of Han Chinese from southern China

Background: Autophagy-related gene 7 (ATG7) plays a key role in autophagy and is strongly implicated in Parkinson's disease (PD). This study investigated the associations of rs1375206 polymorphism in ATG7 gene promoter and plasma ATG7 levels with late-onset sporadic PD in a cohort of Han Chinese from southern China.Methods: Variant genotypes were identified using polymerase chain reaction-restriction fragment length polymorphism and gene sequencing in 124 patients with late-onset sporadic PD, as well as in 105 age- and sex-matched healthy controls. Plasma ATG7 levels were determined using an enzyme-linked immunosorbent assay.Results: No significant differences in genotype distributions were found between the two groups. Stratification analyses by sex and clinical motor subtypes revealed that the differences remained non-significant in each subgroup (all p > 0.05). Plasma ATG7 protein levels were significantly higher in the PD group than in the control group (p = 0.000). Haplotype analysis demonstrated that the A-T haplotype was significantly associated with late-onset sporadic PD (p = 0.045).Conclusion: Our study suggests that the rs1375206 polymorphism in ATG7 may not be associated with late-onset sporadic PD; however, high plasma ATG7 levels and the A-T haplotype may be associated with susceptibility to late-onset sporadic PD in the Han population from Zhejiang and Guangdong provinces.

Comparing responses of dairy cows to short-term and long-term heat stress in climate-controlled chambers

Heat stress (HS) in dairy cows can be classified into short-term heat stress (STHS) and long-term heat stress (LTHS) according to the number of consecutive days in HS. The comparative study of these 2 types of HS is limited in terms of their effects on the production and energy metabolism of cows. In this study, 4 lactating Holstein cows (102.5 ± 12 days in milk, 605 ± 22 kg of body weight, second parity) fitted with rumen fistulae were randomly assigned to 1 of 2 groups in a 2 × 2 crossover design and allocated to 1 of 2 climate-controlled chambers. This study contained 2 periods, each with a control phase and a HS phase. There was a recovery phase between 2 periods. The HS phase comprised either STHS (3 d) or LTHS (7 d) treatments. Data collected from the 3 d of STHS and the last 3 d of LTHS were compared. The chambers were set at thermal neutral conditions (20°C, 50% humidity) during the control and recovery phases or cyclical HS conditions (26-38°C, 50% humidity) during the HS phase. Compared with STHS, LTHS decreased milk yield by 17.2% and dry matter intake by 12.6%, indicating that LTHS caused a more severe decline in milk production and feed intake. In addition, LTHS decreased milk protein concentration by 6.8% and milk protein yield by 22.4%. In comparison with STHS, LTHS decreased rumen liquor volatile fatty acid (29.7%), blood glucose (11.6%), and nonesterified fatty acid (13.6%) concentrations, but increased milk urea nitrogen by 15.1%, blood urea nitrogen by 8.6%, and creatine concentrations by 15.4%. Our results suggest that although reduced feed intake may be mainly responsible for reduced milk production during STHS, impaired rumen metabolism and suppressed mobilization of adipose tissue could be the main reasons for further reduction in milk yield during LTHS.

Unconventional Hall response in the quantum limit of HfTe5

Interacting electrons confined to their lowest Landau level in a high magnetic field can form a variety of correlated states, some of which manifest themselves in a Hall effect. Although such states have been predicted to occur in three-dimensional semimetals, a corresponding Hall response has not yet been experimentally observed. Here, we report the observation of an unconventional Hall response in the quantum limit of the bulk semimetal HfTe5, adjacent to the three-dimensional quantum Hall effect of a single electron band at low magnetic fields. The additional plateau-like feature in the Hall conductivity of the lowest Landau level is accompanied by a Shubnikov-de Haas minimum in the longitudinal electrical resistivity and its magnitude relates as 3/5 to the height of the last plateau of the three-dimensional quantum Hall effect. Our findings are consistent with strong electron-electron interactions, stabilizing an unconventional variant of the Hall effect in a three-dimensional material in the quantum limit.

Epidemiological and clinical characteristics of patients with COVID-19 from a designated hospital in Hangzhou City: a retrospective observational study

INTRODUCTION

The outbreak of coronavirus disease 2019 (COVID-19) has exerted a heavy burden on public health worldwide. We aimed to investigate the epidemiological and clinical characteristics of patients with COVID-19 in a designated hospital in Hangzhou, China.

METHODS

This was a retrospective study that included laboratory-confirmed cases of COVID-19 in XiXi Hospital of Hangzhou from 15 January 2020 to 30 March 2020. We reviewed and analysed the epidemiological, demographic, clinical, radiological, and laboratory features involving these cases. Age-tratification analysis was also implemented.

RESULTS

We analysed 96 confirmed cases. The patients had a mean age of 43 years, with six patients younger than 18 years and 14 patients older than 60 years. No significant gender difference was discovered. Co-morbidities were commonly observed in patients aged over 40 years. Twenty eight of the patients had travelled from Wuhan City, and 51 patients were infected through close contact. Familial clusters accounted for 48 of the cases. The mean incubation time was 7 days, and the symptoms were mainly fever, cough, fatigue, and sore throat. Lymphocytopenia was observed predominantly in patients aged over 60 years. Fifty five patients presented with bilateral pulmonary lesions. The radiological changes were typically distributed in the subpleural area, and pleural effusion rarely occurred. All patients were discharged successfully.

CONCLUSION

During the early stage of the COVID-19 outbreak, half of the patients from a designated hospital in Hangzhou City were discovered as familial clusters. Therefore, strict prevention and control measures during self-isolation should be implemented. Patients aged over 60 years who had underlying co-morbidities were prone to lymphocytopenia and severe infection.

MicroRNA-326 inhibits cell proliferative capacity and invasiveness through inhibiting the expression of ETS1 in nasopharyngeal carcinoma

OBJECTIVE

This study aims to detect microRNA-326 expression in nasopharyngeal carcinoma (NPC) tissues and cell lines and to explore the potential mechanism of microRNA-326 inhibiting the proliferative capacity and invasiveness of NPC cells.

PATIENTS AND METHODS

Quantitative Real Time-Polymerase Chain Reaction (qRT-PCR) was performed to examine microRNA-326 expression in 40 cases of NPC tissue samples and cell lines. Meanwhile, microRNA-326 mimics were transfected into NPC cells to up-regulate microRNA-326 level. Next, the influence of microRNA-326 mimics on the proliferation and invasiveness of NPC cells was observed by Cell Counting Kit-8 (CCK-8) assay and transwell assay, respectively. Bioinformatics analysis was applied to search for target genes which may have direct effects on microRNA-326. An EST1 luciferase reporter vector containing microRNA-326 binding site was constructed and the binding relation between ETS1 and microRNA-326 was detected by Dual-Luciferase reporting assay. Lastly, the underlying mechanism of microRNA-326 and ETS1 in NPC was further verified via cell reverse experiments.

RESULTS

Compared with control group, microRNA-326 expression was found remarkably decreased both in NPC tissue specimens and cell lines. The low expression of microRNA-326 could predict poor prognosis of patients with NPC. In vitro cell experiments revealed that overexpression of microRNA-326 remarkably inhibited the proliferative capacity and invasiveness of NPC cells. Bioinformatics analysis and Dual-Luciferase assay results suggested that microRNA-326 may bind to ETS1. Cell reverse assay indicated that inhibiting ETS1 expression partially reversed the changes in cell biological behavior induced by the down-regulation of microRNA-326 in CNE1 and 5-8F cell lines.

CONCLUSIONS

Overexpression of microRNA-326 in NPC cells could remarkably inhibit the proliferative capacity and invasiveness of NPC cells. In addition, microRNA-326 may participate in the development of NPC by inhibiting ETS1 expression.

Enhanced transforming growth factor-beta signaling and fibrosis in the pectoralis major muscle of broiler chickens affected by wooden breast myopathy

Fibrosis has also been recorded as a prominent pathological feature within wooden breast (WB) myopathy of broiler chickens. This study was conducted to evaluate the accumulation of fibril collagen, deposition of the extracellular matrix (ECM) components, and the underlying mechanism mediating the pathogenic fibrotic process in the pectoralis major (PM) muscle of WB-affected birds. Broiler chickens were categorized into the control and WB groups based on the evaluation of myopathic lesions. Results indicated that the total content and area of collagen in cross-sections of the PM muscle, as well as the augmented expression of collagen-I and fibronectin in the ECM, were greatly increased in birds with WB. Wooden breast myopathy upregulated expressions of transforming growth factor-beta (TGF-β) and the phosphorylation of Smad 2 and 3, thereby activating TGF-β-mediated Smad signaling pathway, which further enhanced the transcription of profibrotic mediators. In addition, regulators involved in collagen biosynthesis and cross-linking including prolyl 4-hydroxylase, lysyl oxidase, lysyl hydroxylase, and decorin were increased in the WB muscle. Finally, the expressions of both matrix metalloproteinases (MMP) and tissue inhibitor of metalloproteinases (TIMP) were increased in the WB muscle, which might be related with reduced ECM remodeling. Overall, WB myopathy induces severe fibrosis by enhancing ECM deposition and collagen cross-linking in the PM muscle of broiler chickens, possibly via the activation of TGF-β signaling and the dysregulation of the MMP and TIMP system.

Tafolecimab, a novel potential long-acting PCSK9 monoclonal antibody: efficacy and safety in healthy and hypercholesterolemia subjects

Background

LDL cholesterol (LDL-C) is a well-established risk factor for cardiovascular disease. PCSK9 binds LDL receptors, targeting them for degradation. The dosing intervals for currently available PCSK9 monoclonal antibodies are once every 2 or 4 weeks. Tafolecimab, a novel recombinant human PCSK9 monoclonal antibody, was found to have higher affinity with PCSK9 and show longer LDL-C reduction compared to evolocumab in preclinical studies.

Purposes

The objectives for the SAD and MAD studies were to investigate the safety and efficacy of tafolecimab and explore the optimal dosing schedule.

Methods

The phase 1 study was a randomized, placebo-controlled, double-blind, single-ascending dose study (SAD) in Chinese healthy subjects, who were randomized 3:1 to tafolecimab and placebo (n=58). SAD subjects received tafolecimab subcutaneously at 25/75/150/300/450/600mg, or intravenously at 75/450mg, monitored up to day 84. The phase 2 study was a randomized, double-blind, placebo-controlled, repeated-dosing, multiple ascending dose (MAD) study in patients with hypercholesterolemia, who were randomized 4:1 to tafolecimab and placebo (n=60). MAD subjects received tafolecimab subcutaneously at 75/140mg every 2 weeks, 300/420mg every 4weeks, 450/600mg every 6 weeks up to day 84 or 98 with 3 months follow-up.

Results

In the SAD, the maximum mean reduction in LDL-C ranged from 52.2% to 72.1% and was achieved as early as 5 days (figure 1a). The duration of LDL-C reduction was tafolecimab dose dependent. In the MAD, the mean LDL-C concentrations were reduced by tafolecimab for each dose at 12 weeks relative to baseline (ranging from 54.30% to 72.26%; p&lt;0.001). Particularly, a 56.52% (−72.50%, −40.54%) reduction of LDL-C was observed in the cohort of 600mg Q6W. The effect sustained till week 14 (8 weeks after the last dose) where there was still a 43.46% (−60.96%, −25.96%) reduction from baseline (figure 1b). The mean reduction of Lp(a) at week 12 ranged from 24.04% to 50.59% relative to baseline. Tafolecimab reduced the other lipids when comparing with placebo. The pharmacokinetics/pharmadynamics (LDL-C) profiles of tafolecimab were well characterised and support the potential dosing interval of 6–8 weeks subcutaneously.

Both healthy and hypercholesterolemia subjects are generally tolerable to tafolecimab. Reported treatment-emergent adverse events (TEAEs) were: tafolecimab 23 (52.3%) vs. placebo 8 (57.1%); tafolecimab 34 (70.8%) vs. placebo 9 (75.0%) in the SAD and MAD respectively. There were no serious TEAEs or events leading to death or treatment discontinuation in both SAD and MAD.

Conclusions

Tafolecimab was well tolerated in both healthy and hypercholesterolemia in Chinese subjects, and improved lipid profile including LDL-C, Lp(a) and other lipids. The sustained effects on LDL-C suggests the potential of tafolecimab as a long-lasting PCSK9 inhibitor with dosing interval of 6–8 weeks or beyond.

Figure 1. LDL-C: Percent change from baseline

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Innovent Biologics (Suzhou), China

Association between pre-infarction angina and culprit-lesion morphology in patients with ST-segment elevation myocardial infarction: an optical coherence tomography study

Background

Previous studies reported the cardiac protection effect of pre-infarction angina (PIA) in patients with acute myocardial infarction (AMI). However, the association between PIA and culprit plaques characteristics in AMI patients through optical coherence tomography (OCT)assessment remains unclear.

Purpose

We sought to identify culprit-plaque morphology associated with PIA in patients with ST-segment elevation myocardial infarction (STEMI) using OCT.

Methods

A total of 279 STEMI patients who underwent intravascular OCT of culprit-lesion were included. Baseline clinical data and culprit-plaque characteristics were compared between the PIA group the non-PIA group.

Results

Patients with PIA represented 54.8% of the study population (153 patients). No differences were observed in clinical and angiographic data between two groups, except STEMI onset with exertion was significantly less common in PIA group (24.2% versus 40.5%, P=0.004). Patients with PIA exhibited a significantly lower incidence of plaque rupture (40.5% versus 61.9%, P&lt;0.001) and lipid-rich plaques (48.4% versus 69.0%, P=0.001). The thin-cap fibroatheroma (TCFA) prevalence was lower in PIA group, presenting a thicker fibrous cap thickness, although statistically significant differences were not observed (20.3% versus 30.2%, P=0.070; 129.1±92.0μm versus 111.4±78.1μm, P=0.088; respectively). Multivariate logistic regression analysis indicated that PIA was an independent negative predictor for plaque rupture (odds ratio: 0.44, 95% confidence interval: 0.268–0.725, P=0.001).

Conclusion

STEMI patients with PIA showed a significantly lower prevalence of plaque rupture and lipid-rich plaques in culprit-lesion than non-PIA group, implying different mechanisms of STEMI attack.

Flow chart + Bar graphs of OCT findings

Funding Acknowledgement

Type of funding source: Public Institution(s). Main funding source(s): Association between pre-infarction angina and culprit-lesion morphology in patients with ST-segment elevation myocardial infarction: An optical coherence tomography study