Three-dimensional pseudo-continuous arterial spin-labelled perfusion imaging for diagnosing upper cervical lymph node metastasis in patients with nasopharyngeal carcinoma: a whole-node histogram analysis

AIM

To evaluate whole-node histogram parameters of blood flow (BF) maps derived from three-dimensional pseudo-continuous arterial spin-labelled (3D pCASL) imaging in discriminating metastatic from benign upper cervical lymph nodes (UCLNs) for nasopharyngeal carcinoma (NPC) patients.

MATERIALS AND METHODS

Eighty NPC patients with a total of 170 histologically confirmed UCLNs (67 benign and 103 metastatic) were included retrospectively. Pre-treatment 3D pCASL imaging was performed and whole-node histogram analysis was then applied. Histogram parameters and morphological features, such as minimum axis diameter (MinAD), maximum axis diameter (MaxAD), and location of UCLNs, were assessed and compared between benign and metastatic lesions. Predictors were identified and further applied to establish a combined model by multivariate logistic regression in predicting the probability of metastatic UCLNs. Receiver operating characteristic (ROC) curves were used to analyse the diagnostic performance.

RESULTS

Metastatic UCLNs had larger MinAD and MinAD/MaxAD ratio, greater energy and entropy values, and higher incidence of level II (upper jugular group), but lower BF10th value than benign nodes (all p<0.05). MinAD, BF10th, energy, and entropy were validated as independent predictors in diagnosing metastatic UCLNs. The combined model yielded an area under the curve (AUC) of 0.932, accuracy of 84.42 %, sensitivity of 80.6 %, and specificity of 90.29 %.

CONCLUSIONS

Whole-node histogram analysis on BF maps is a feasible tool to differentiate metastatic from benign UCLNs in NPC patients, and the combined model can further improve the diagnostic efficacy.

Bacteroid cerium oxide particles promote macrophage polarization to achieve early vascularization and subsequent osseointegration around implants

The establishment of an osseointegration is crucial for the long-term stability and functionality of implant materials, and early angiogenesis is the key to successful osseointegration. However, the bioinertness of titanium implants affects osseointegration, limiting their clinical application. In this study, inspired by the rapid polarization of macrophages following the phagocytosis of bacteria, we developed bacteroid cerium oxide particles; these particles were composed of CeO2 and had a size similar to that of Bacillus (0.5 μ m). These particles were constructed on the implant surfaces using a hydrothermal method. In vitro experiments demonstrated that the particles effectively decreased the reactive oxygen species (ROS) levels in macrophages (RAW264.7). Furthermore, these particles exerted effects on M1 macrophage polarization, enhanced nitric oxide (NO) secretion to promote vascular regeneration, and facilitated rapid macrophage transition to the M2 phenotype. Subsequently, the particles facilitated human umbilical vein endothelial cell (HUVEC) migration. In vivo studies showed that these particles rapidly stimulated innate immune responses in animal models, leading to enhanced angiogenesis around the implant and improved osseointegration. In summary, the presence of bacteroid cerium oxide particles on the implant surface regulated and accelerated macrophage polarization, thereby enhancing angiogenesis during the immune response and improving peri-implant osseointegration.

Fabrication of NiCo Bimetallic MOF Films on 3D Foam with Assistance of Atomic Layer Deposition for Non-Invasive Lactic Acid Sensing

Lactic acid (LA) is an important downstream product of glycolysis in living cells and is abundant in our body fluids, which are strongly associated with diseases. The development of enzyme-free LA sensors with high sensitivity and low consumption remains a challenge. 2D metal-organic frameworks (MOFs) are considered to be promising electrochemical sensing materials and have attracted much attention in recent years. Compared to monometallic MOFs, the construction of bimetallic MOFs (BMOFs) can obtain a larger specific surface area, thereby increasing the exposed active site. 3D petal-like NixCoy MOF films on nickel foams (NixCoy BMOF@Ni foams) are successfully prepared by combining atomic layer deposition-assisted technology and hydrothermal strategy. The established NixCoy BMOF@Ni foams demonstrate noticeable LA sensing activity, and the study is carried out on behalf of the Ni1Co5 BMOF@Ni foam, which has a sensitivity of up to 9030 μA mM-1 cm-2 with a linear range of 0.01-2.2 mM and the detection limit is as low as 0.16 μM. Additionally, the composite has excellent stability and repeatability for the detection of LA under a natural air environment with high accuracy and reliability. Density functional theory calculation is applied to study the reaction process between composites and LA, and the result suggests that the active site in the NiCo BMOF film favors the adsorption of LA relative to the active site of monometallic MOF film, resulting in improved performance. The developed composite has a great potential for the application of noninvasive LA biosensors.

[The functional differences of macrophages derived from murine bone marrow and peritoneal cavity]

Objective To compare the functional differences between bone marrow derived macrophages and peritoneal macrophages, which may provide the basis for the selection of macrophages in immunological research and immunoregulatory drug evaluation. Methods Marophage colony-stimulating factor (M-CSF) was used to induce the differentiation of bone marrow monocytes into macrophages, and thioglycolate medium was used to induce peritonitis to obtain peritoneal macrophages. After both macrophages being stimulated by zymosan, LPS, R848 and CpG respectively, mRNA levels of tumor necrosis factor α(TNF-α), interleukin 6(IL-6), macrophage inflammatory protein 1α(MIP-1α), monocyte chemoattractant protein 1(MCP-1) were measured by Real-time fluorescent quantitative PCR and the concentrations of secreted TNF-α, IL-6, MIP-1α and MCP-1 were detected by ELISA. In addition, the expression of costimulatory molecules CD80, CD86, CD40 and histocompatibility complex II (MHC II) on the cell surface was analyzed by flow cytometry. Results After inducing by different TLR ligands, mRNA expression levels of inflammatory cytokines and chemokines were increased in both macrophages. The secretion of TNF-α, IL-6, MIP-1α and MCP-1 in peritoneal macrophages and the expression of CD86 and MHC II on the surface of peritoneal macrophages were significantly higher than those of bone marrow derived macrophages. Conclusion There are significant differences in the expression of inflammatory factors, chemokines, costimulatory molecules, and histocompatibility complex between bone marrow derived macrophages and peritoneal macrophages. Peritoneal macrophages have more complete macrophage function and is more suitable for immunological research and immunomodulatory drug evaluation.

Icaritin Sensitizes Thrombin- and TxA2-Induced Platelet Activation and Promotes Hemostasis via Enhancing PLCγ2-PKC Signaling Pathways

BACKGROUND

 Vascular injury results in uncontrollable hemorrhage in hemorrhagic diseases and excessive antithrombotic therapy. Safe and efficient hemostatic agents which can be orally administered are urgently needed. Platelets play indispensable roles in hemostasis, but there is no drug exerting hemostatic effects through enhancing platelet function.

METHODS

 The regulatory effects of icaritin, a natural compound isolated from Herba Epimedii, on the dense granule release, thromboxane A2 (TxA2) synthesis, α-granule release, activation of integrin αIIbβ3, and aggregation of platelets induced by multiple agonists were investigated. The effects of icaritin on tail vein bleeding times of warfarin-treated mice were also evaluated. Furthermore, we investigated the underlying mechanisms by which icaritin exerted its pharmacological effects.

RESULTS

 Icaritin alone did not activate platelets, but significantly potentiated the dense granule release, α-granule release, activation of integrin αIIbβ3, and aggregation of platelets induced by thrombin and U46619. Icaritin also shortened tail vein bleeding times of mice treated with warfarin. In addition, phosphorylated proteome analysis, immunoblotting analysis, and pharmacological research revealed that icaritin sensitized the activation of phospholipase Cγ2 (PLCγ2)-protein kinase C (PKC) signaling pathways, which play important roles in platelet activation.

CONCLUSION

 Icaritin can sensitize platelet activation induced by thrombin and TxA2 through enhancing the activation of PLCγ2-PKC signaling pathways and promote hemostasis, and has potential to be developed into a novel orally deliverable therapeutic agent for hemorrhages.

A polypeptide derived from pilose antler ameliorates CUMS-induced depression-like behavior by SENP2-PLCβ4 signaling axis

Neurogenesis is known to be closely associated with depression. We aimed to investigate whether a polypeptide monomer derived from pilose antler (polypeptide sequence LSALEGVFYP, PAP) exerts an antidepressant effect by influencing neurogenesis, and to elucidate the mechanism of its antidepressant action. Behavioral tests were performed to observe the antidepressant effect of PAP. Neurogenesis in the dentate gyrus (DG) region of hippocampus was observed by immunofluorescence. The expression of key proteins of Sentrin/SUMO-specific proteases 2 (SENP2)- Phosphoinositide-specific phospholipase C beta 4 (PLCβ4) pathway was accessed by co-immunoprecipitation (Co-IP), and the calcium homeostasis associated proteins were observed via Western blot (WB). Subsequently, temozolomide (TMZ) pharmacologically blocked neurogenesis to verify the antidepressant effect of PAP on neurogenesis. The mechanism of PAP antidepressant effect was verified by constructing a sh-SENP2 virus vector to silence SENP2 protein. Finally, corticosterone (CORT)-induced PC12 cell model was used to verify whether PAP was involved in the process of deconjugated PLCβ4 SUMOylated. The results showed that PAP improved depression-like behavior and neurogenesis induced by chronic unpredictable mild stimulation (CUMS). In addition, PAP acted on SENP2-PLCβ4 pathway to deconjugate the SUMOylation of PLCβ4 and affect calcium homeostasis. Pharmacological blockade of neurogenesis by TMZ treatment impaired the antidepressant efficacy of PAP. Knockout of SENP2 in the CUMS model attenuated the antidepressant response of PAP, and the impaired neurogenesis was not ameliorated by PAP treatment. In summary, PAP acted on the SENP2-PLCβ4 signaling pathway to inhibit the SUMOylation of PLCβ4 and maintain calcium homeostasis, thereby protecting neurogenesis and playing an antidepressant role.

[Effect of recombinant human thrombin for hemostasis in liver resection: a randomized controlled phase Ⅲ clinical trial]

Objective: To evaluate the hemostatic efficacy, safety and immunogenicity of recombinant human thrombin in the treatment of liver wounds that still ooze after conventional surgical hemostasis. Methods: A multicenter, stratified randomized, double-blind, placebo-controlled phase Ⅲ trial with a planned enrollment of 510 subjects at 33 centers, with a 2∶1 randomization to the thrombin group versus the placebo group. An interim analysis will be conducted after approximately 70% of the subjects have completed the observation period. The primary efficacy endpoint was the rate of hemostasis within 6 minutes at the point of bleeding that could be evaluated. Safety analysis was performed one month after surgery, and the positive rates of anti-drug antibody (ADA) and neutralizing antibody were evaluated. Results: At the interim analysis, a total of 348 subjects had been randomized and received the study drug (215 were male and 133 were female). They were aged 19-69 (52.9±10.9)years. Among them, 232 were in the thrombin group and 116 were in the placebo group, with balanced and comparable demographics and baseline characteristics between the two groups. The hemostasis rate at 6 minutes was 71.6% (95%CI:65.75%-77.36%) in the thrombin group and 44.0% (95%CI: 34.93%-53.00%) in the placebo group, respectively (P<0.001). No grade≥3 drug-related adverse events and no drug-related deaths were reported from the study.No recombinant human thrombin-induced immunologically-enhanced ADA or immunologically-induced ADA was detected after topical use in subjects. Conclusion: Recombinant human thrombin has shown significant hemostatic efficacy and good safety in controlling bleeding during liver resection surgery, while also demonstrating low immunogenicity characteristics.

Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm

We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{μ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{μ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{μ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision.

The Role of Radiation Therapy for Metastatic Cervical Cancer

PURPOSE/OBJECTIVE(S)

Survival rates for women with metastatic cervical cancer (CC) are low, with limited management options. Radiation therapy (RT) for metastatic disease has led to prolonged survival in other malignancies, however, the data are scarce in CC. Herein, we evaluated the effect of RT for metastatic CC.

MATERIALS/METHODS

A total of 58 patients with metastatic CC between September 2019 and January 2023 were retrospectively analyzed. All the patients were treated with platinum-based chemotherapy combined with targeted therapy or immunotherapy followed with or without RT (NRT). The recent efficacy, survival status and prognostic factors were analyzed statistically.

RESULTS

Objective response rate (ORR) was 63.6% with one complete and twenty partial responses in RT group (n = 33) and 40.0% with two complete and eight partial responses in NRT group (n = 25), respectively (p = 0.074). Disease control rate (DCR) of the RT and NRT groups were 79.4% vs 80.0%, respectively (p = 0.861). Median follow-up time was 17 months (3-39months). In RT group, 11(33.3%) patients experienced local regional or distant failure and 9 (27.3%) patients were dead. In NRT group, 15(60%) patients had progression and 8 (32%) patients dead. There was no significant difference between the two groups in overall survival (OS); however, RT group displayed superior progression-free survival (PFS) (1-year OS: 72.7% vs. 68.0%, p = 0.460; 1-year PFS: 66.7% vs. 40.0%, p = 0.039). The multivariate analysis showed that RT, immunotherapy, lymph node metastasis only relevant predictor of superior PFS but not OS. In subgroup analysis, patients treated with RT appeared to have a better PFS in some specific cohorts, such as age>45 years (72.0% vs 36.4% P = 0.015), squamous carcinoma histology (71.0% vs 40.9% P = 0.017), metastatic at diagnosis (75.0% vs 47.6% P = 0.012), non-targeted therapy (72.4% vs 43.8% P = 0.040). No significant increase in treatment-related toxicity was observed in the RT group compared with the NRT group.

CONCLUSION

RT provided superior PFS in metastatic CC patients compared to NRT, and well tolerated. Moreover, RT, immunotherapy, lymph node metastasis only were independent significant prognostic factors for PFS. Subgroup analysis showed that combination of RT and chemotherapy obtained favorable PFS in metastatic CC patients with age>45 years, squamous carcinoma histology, metastatic at diagnosis, non-targeted therapy. Studies with a larger sample size and longer follow-up are warranted.

Radiation Induced Lung Injury in Rats after Pre-Oxygenation Radiotherapy

PURPOSE/OBJECTIVE(S)

Deep inspiratory breath holding (DIBH) has been widely used during the radiotherapy of thoracic tumors. The main disadvantage of voluntary DIBH is the short duration of each breath hold. The hypocapnia induced by hyperoxia (oxygen concentration > 50%) pre-oxygenation (PreO2) combined with mechanical hyperventilation has been reported to prolong the duration of single breath hold, but its safety remains controversial, especially the sensitivity of lung tissue to radiation damage under hyperoxia exposure has not been elucidated. In this study, we aim to investigate the changes of radiation induced lung injury in rats after PreO2 radiation.

MATERIALS/METHODS

We evaluated the lung tissue of rats at different time points (48h, 2w, 4w, 8w, 12w) after thoracic radiation (15Gy single fraction to the right lung), and sequenced the transcriptome of lung tissue at 48 hours after irradiation. Rat cohorts (n = 7/group): 1. Control (Con); 2. Radiation group (RT); 3. Pre-oxygenation (oxygen concentration > 90%) for 8 hours before thoracic radiation (PreO2).

RESULTS

The inflammatory exudation emerged in the pulmonary interstitium at 48 hours, and reached the most serious alveolitis after four weeks of irradiation (the comparison of alveolitis scores in RT4w vs Con4w and PreO2(4w) vs Con4w, P<0.001) on hematoxylin-eosin staining. While the alveolitis scores in RT group and PreO2 group were not statistically different at each time point. Masson staining showed that the pulmonary fibrosis in the RT group and the PreO2 group reached an obvious pathological change at 12 weeks after irradiation, but the difference between the two groups was not significant. Transcriptome sequencing showed that the number of differential genes in PreO2 vs Con was 559 (302 up-regulated genes and 257 down-regulated genes). The GO enrichment analysis indicated that chromosome segregation was the most significant functional item with P value in the comparative analysis, and the KEGG enrichment analysis suggested that cell division was the most significant enrichment pathway of these differential genes. While there was a small quantity of differential genes in PreO2 vs RT group (3 up-regulated genes and 12 down-regulated genes). Pentose and glucuronate conversions were the most significant enrichment pathway of these differential genes.

CONCLUSION

This study demonstrated that PreO2 radiotherapy did not increase the severity of radiation induced lung injury in rats compared to conventional radiotherapy. Further study should be conducted to confirm these results and to investigate the regulatory mechanism of pneumonia caused by PreO2 radiotherapy.

Deep Learning-Based Multi-Modality Segmentation of Primary Gross Tumor Volume in CT and MRI for Nasopharyngeal Carcinoma

PURPOSE/OBJECTIVE(S)

The delineation of primary gross tumor volume (GTV) of nasopharyngeal carcinoma (NPC) is an essential step for radiotherapy planning. In clinical practice, radiation oncologists manually delineate the GTV in planning CT with the help of diagnostic MRI. This is because NPC tumors are closely adjacent to many important anatomic structures, and CT and MRI provide complementary strength to accurately determine the tumor extension boundary. Manual delineation is time-consuming with the potential registration errors between MRI and CT decreasing the delineation accuracy. In this study, we propose a fully automated GTV segmentation method based on CT and MRI by first aligning MRI to CT, and then, segmenting the GTV using a multi-modality deep learning model.

MATERIALS/METHODS

We collected 104 nasopharyngeal carcinoma patients with both planning CT and diagnostic MRI scans (T1 & T2 phases). An experienced radiation oncologists manually delineated the GTV, which was further examined by another senior radiation oncologist. Then, a coarse to fine cross-modality registration from MRI to CT was conducted as follows: (1) A rigid transformation was performed on MRI to roughly align MRI to CT with similar anatomic position. (2) Then, the region of interest (RoI) on both CT and rigid-transformed MRI were cropped. (3) A leading cross-modality deformable registration algorithm, named DEEDS, was applied on the cropped MRI and CT RoIs to find an accurate local alignment. Next, using CT and registered MRI as the combined input, a multi-modality deep segmentation network based on nnUNet was trained to generate the GTV prediction. 20% patients were randomly selected as the unseen testing set to quantitatively evaluate the performance.

RESULTS

The quantitative NPC GTV segmentation performance is summarized in Table 1. The deep segmentation model using CT alone achieved reasonable high performance with 76.6% Dice score and 1.34mm average surface distance (ASD). When both CT and registered MRI were used, the segmentation model further improved the performance by 0.9% Dice score increase and 11% relative ASD error reduction, demonstrating the complementary strength of CT and MRI in determining NPC GTV. Notably, the achieved 77.5% Dice score and 1.19mm ASD by the multimodality model is among the top performing results reported in recent automatic NPC GTV segmentation using either CT or MRI modality.

CONCLUSION

We developed a fully automated multi-modal deep-learning model for NPC GTV segmentation. The developed model can segment the NPC GTV in high accuracy. With further optimization and validation, this automated model has potential to standardize the NPC GTV segmentation and significantly decrease the workload of radiation oncologists in clinical practice.

Zuojinwan ameliorates CUMS-induced depressive-like behavior through inducing ubiquitination of MyD88 via SPOP/MyD88/NF-κB pathway

ETHNOPHARMACOLOGICAL RELEVANCE

Zuojinwan (ZJW) is a traditional Chinese medicine compound, which is often used clinically to treat gastritis and has anti-inflammatory activity. It was found that ZJW is involved in suppressing the expression of inflammatory factors, and neuroinflammation is thought to be associated with the development of depression.

AIM OF THE STUDY

In this study, we investigated whether ZJW could exert antidepressant effects by regulating MyD88 ubiquitination in depressed mice and attempted to elucidate the possible mechanisms.

MATERIALS AND METHODS

Six active compounds of Zuojinwan (ZJW) were identified by HPLC. Then, the effects of ZJW on depression-like behavior in mice were investigated by constructing a chronic unpredictable mild stimulation (CUMS) mouse model. Meanwhile, the effect of ZJW on hippocampal neurons was investigated by Nissl staining. In addition, western blotting, PCR, ELISA, co-immunoprecipitation and immunostaining were used to explore whether ZJW could inhibit neuroinflammation through SPOP/MyD88/NF-κB pathway and thus produce antidepressant effects. Finally, we constructed the AAV-Sh-SPOP virus vector to silence SPOP and verify the mechanism of ZJW's antidepressant action.

RESULTS

ZJW could dramatically ameliorate the depressive behavior induced by CUMS stimulation and alleviate hippocampal neuronal damage. CUMS stimulation resulted in decreased SPOP expression, impaired MyD88 ubiquitination, and activation of downstream NF-κB signaling, which could be reversed by ZJW. In addition, ZJW could significantly ameliorate the abnormal activation of microglia, and the excessive levels of pro-inflammatory factors were inhibited. By blocking the expression of SPOP, we found that ZJW exerted anti-inflammatory and antidepressant effects mainly by promoting the ubiquitination of MyD88 and inhibiting the activation of downstream inflammatory signals.

CONCLUSION

In conclusion, ZJW possesses alleviating effects on depression induced by CUMS stimulation. ZJW can inhibit neuroinflammation and improve neuroinflammation-induced depression-like behaviors through SPOP/MyD88/NF-κB pathway.

Context-aware deep network for coronary artery stenosis classification in coronary CT angiography

Automatic coronary artery stenosis grading plays an important role in the diagnosis of coronary artery disease. Due to the difficulty of learning the informative features from varying grades of stenosis, it is still a challenging task to identify coronary artery stenosis from coronary CT angiography (CCTA). In this paper, we propose a context-aware deep network (CADN) for coronary artery stenosis classification. The proposed method integrates 3D CNN with Transformer to improve the feature representation of coronary artery stenosis in CCTA. We evaluate the proposed method on a multicenter dataset (APOLLO study with NCT05509010). Experimental results show that our proposed method can achieve the accuracy of 0.84, 0.83, and 0.86 for stenosis diagnosis on the lesion, artery, and patient levels, respectively.

Development and validation of a survival prediction model and risk stratification for pancreatic neuroendocrine neoplasms

PURPOSE

We explored risk variables associated with cancer-specific survival (CSS) in patients with pancreatic neuroendocrine neoplasms (PNENs) and created a network dynamic nomogram model to predict patient survival time.

METHODS

A total of 7750 patients with PNENs were included in this analysis, including 134 with functional PNENs and 7616 with nonfunctional PNENs. Clinical feature and prognosis differences between functional and nonfunctional PNENs were compared. Independent prognostic factors affecting CSS were analyzed by univariate and multifactorial Cox regression. Nomogram and web-based prognosis prediction of PNENs were developed and validated by C indices, decision curve analysis, and calibration plots.

RESULTS

Patients with functional PNENs were younger at diagnosis than those with nonfunctional PNENs. Functional PNENs had better prognoses than nonfunctional PNENs (5-year survival rates: 78.55% and 71.10%, respectively). Univariate and multifactorial Cox regression analyses showed that tumor infiltration (T), nodal metastasis (N), metastasis (M), tumor site, differentiation grade, age, marital status, and surgical treatment were independent prognostic risk factors for CSS, which were included in the prognostic nomogram and web-based prognosis calculator. The calibration plots and decision curve analysis showed that the nomogram had excellent prediction and clinical practical ability. The C indices for CSS in the training and validation cohorts were 0.848 (95% CI 0.838-0.8578) and 0.823 (95% CI 0.807-0.839), respectively. We scored all patients according to the nomogram and divided patients into three different risk groups. The prognosis of the low-risk population was significantly better than those of the middle- and high-risk populations based on Kaplan-Meier survival curve.

CONCLUSION

We analyzed the clinical features of PNENs and developed a convenient and web dynamic nomogram to predict CSS.

Modulating the Performance of the SAW Strain Sensor Based on Dual-Port Resonator Using FEM Simulation

Surface acoustic wave (SAW) strain sensors fabricated on piezoelectric substrates have attracted considerable attention due to their attractive features such as passive wireless sensing ability, simple signal processing, high sensitivity, compact size and robustness. To meet the needs of various functioning situations, it is desirable to identify the factors that affect the performance of the SAW devices. In this work, we perform a simulation study on Rayleigh surface acoustic wave (RSAW) based on a stacked Al/LiNbO₃ system. A SAW strain sensor with a dual-port resonator was modeled using multiphysics finite element model (FEM) method. While FEM has been widely used for numerical calculations of SAW devices, most of the simulation works mainly focus on SAW modes, SAW propagation characteristics and electromechanical coupling coefficients. Herein, we propose a systematic scheme via analyzing the structural parameters of SAW resonators. Evolution of RSAW eigenfrequency, insertion loss (IL), quality factor (Q) and strain transfer rate with different structural parameters are elaborated by FEM simulations. Compared with the reported experimental results, the relative errors of RSAW eigenfrequency and IL are about 3% and 16.3%, respectively, and the absolute errors are 5.8 MHz and 1.63 dB (the corresponding V_out/V_in is only 6.6%). After structural optimization, the obtained resonator Q increases by 15%, IL decreases by 34.6% and the strain transfer rate increases by 2.4%. This work provides a systematic and reliable solution for the structural optimization of dual-port SAW resonators.

Seven new 3,4-dihydro-furanocoumarin derivatives from Angelica dahurica

Objective

To study the chemical constituents of the roots of Angelica dahurica, a well-known Chinese herbal medicine named Baizhi in Chinese.

Methods

Compounds were separated by various chromatographies, and the structures of new compounds were elucidated based on the analysis of their spectroscopic and spectrometric data (1D, 2D NMR, HRESI MS, IR, and UV). The absolute configurations of new compounds were determined by the calculated electronic circular dichroism and chemical derivatization. The inhibitory activities of all isolates against nitric oxide (NO) production were evaluated using lipopolysaccharide-activated RAW 264.7 macrophage cells.

Results

Seven new 3,4-dihydro-furanocoumarin derivatives (1a/1b, 2a/2b, 3a/3b, 4) together with a known furanocoumarin (5) were isolated from the roots of A. dahurica. The new compounds included three pairs of enantiomers, (4S, 2''R)-angelicadin A (1a)/(4R, 2''S)-angelicadin A (1b), (4S, 2''S)-angelicadin A (2a)/(4R, 2''R)-angelicadin A (2b), and (4S, 2''S)-secoangelicadin A (3a)/(4R, 2''R)-secoangelicadin A (3b), together with (4R, 2''R)-secoangelicadin A methyl ester (4). The known xanthotoxol (5) inhibited the NO production with the half-maximal inhibitory concentration (IC50) value of (32.8 ± 0.8) µmol/L, but all the new compounds showed no inhibitory activities at the concentration of 100 µmol/L.

Conclusion

This is the first report of the discovery of 3,4-dihydro-furanocoumarins from A. dahurica. The results are not only meaningful for the understanding of the chemical constituents of A. dahurica, but also enrich the reservoir of natural products.

Association of residential greenness with the risk of metabolic syndrome in Chinese older adults: a longitudinal cohort study

AIMS

We aimed to investigate the association between residential greenness and MetS in older Chinese adults.

METHODS

Longitudinal data on sociodemographic characteristics and lifestyle were collected from the Shenzhen Healthy Ageing Research (SHARE) cohort. Greenness exposure was assessed through satellite-derived Normalized Difference Vegetation Index (NDVI) values in the 250-m, 500-m, and 1250-m radius around the residential address for each participant. MetS was defined by standard guidelines for the Chinese population.

RESULTS

A total of 49,893 older Chinese adults with a mean age of 70.96 (SD = 5.26) years were included in the study. In the fully adjusted models, participants who lived in the highest quartile of NDVI_250-m, NDVI_500-m, and NDVI_1250-m had a 15% (odds ratio, OR = 0.85, 95% confidence interval, CI: 0.80-0.90), 12% (OR = 0.88, 95% CI: 0.83-0.93), and 11% (OR = 0.89, 95% CI: 0.85-0.95) lower incidence of MetS, respectively, than those living in the lowest quartile (all p-_trend < 0.01). Interactions and subgroup analyses showed that age, sex, smoking status, and drinking status were significant effect modifiers (p-_interaction for all NDVI < 0.05).

CONCLUSIONS

Residential greenness is associated with a lower risk of MetS in Chinese older adults, especially for young older adults, females, non-smokers, and non-drinkers.

Plasma amyloid-beta levels and risk of new-onset atrial fibrillation in the general population

Background

Atrial fibrillation (AF) is a major health burden worldwide, with significant sex differences in epidemiology and risk factors. Amyloid-β40 (Aβ40) and Amyloid-β42 (Aβ42), the hallmark of cerebral amyloid angiopathy, have recently been linked to prevalence and prognosis of several cardiovascular outcomes including stroke and coronary heart disease. However, whether these biomarkers are associated with incident AF remains largely unknown.

Purpose

To investigate the associations between plasma concentrations of Aβ40 and Aβ42 with new-onset AF.

Methods

4,134 participants without a history of AF at baseline (from 2002 to 2005) with qualified plasma samples in the Rotterdam Study were included in this study. AF was diagnosed by electrocardiograms, general practitioners' and hospital records. Cox proportional hazards regression models with natural cubic splines were used to assess the linear/nonlinear association between biomarkers and risk of new-onset AF. All models were adjusted for traditional cardiovascular risk factors.

Results

Mean age was 71.3±7.2 years and 2,383 (57.6%) were women. Median follow-up time was 9.2 years. In the fully adjusted model, higher levels of Aβ40 [hazard ratio, 95% confidence interval: 1.16 (1.05–1.28)] and Aβ42 [1.19 (1.09–1.31)], as well as Amyloid-β42 to β40 ratio (Aβ42/40) [1.09 (1.02–1.17)] were significantly associated with incident AF. The observed association between Aβ40 and AF attenuated after mutual adjustment for Aβ42 [1.05 (0.92–1.19)]. In addition, a J-shaped association was found between Aβ40 and AF with the lowest AF risk at Aβ40 values of 212.5 pg/ml.

Conclusions

Both Aβ40 and Aβ42 were independently significantly associated with new-onset AF in the general population independent of cardiovascular risk factors. Findings also suggest a stronger association between AF onset and Aβ42 and AF onset, compared to Aβ40. A nonlinear association was found between Aβ40 and AF, reflecting a substantially increased AF risk among participants with severely increased Aβ40 values.

Funding Acknowledgement

Type of funding sources: None.

Cardiometabolic multimorbidity and lifetime risk of atrial fibrillation among men and women

Background

Atrial fibrillation (AF) is the most common cardiac arrythmia worldwide, with an increased risk of comorbidity, and significant sex differences in pathophysiology and prognosis. Cardiometabolic disorders, including obesity, hypertension, diabetes mellitus, coronary heart disease, stroke, and heart failure commonly coexist with AF. However, the sex-specific patterns and (combined) impact of cardiometabolic disorders on the risk of new-onset AF remains largely unknown.

Purpose

To examine the association between patterns of cardiometabolic multimorbidity and new-onset AF and lifetime risk of AF incidence among men and women.

Methods

4,113 men and 5,432 women free of prevalent AF at baseline (from 1996 to 2008) from the Rotterdam Study were included. AF incidents were assessed by electrocardiograms and general practitioners' and hospital records, and followed up to January 1st, 2014. Sex-specific Cox proportional hazards regression models were used to assess the association between the amount of cardiometabolic disorders and risks of new-onset AF. Models were adjusted for traditional cardiovascular risk factors. Remaining lifetime risk for AF was estimated across the cardiometabolic multimorbidity groups at index ages of 55, 65, and ≥75 years up to age 108.

Results

Mean age at baseline was 65.5±9.4 years. Median follow-up time was 10.8 years. In the fully-adjusted model, a significant association was found between the amount of cardiometabolic disorders and incident AF among women but not men. Compared to women without cardiometabolic disorders, women with 3 (hazard ratios, 95% conference intervals: 2.17 (1.24–3.79)) and ≥4 comorbidities (4.58 (2.22–9.48)) had higher AF risks. The lifetime risk for AF was significantly increased with the number of cardiometabolic disorders among both men and women. At index age of 55 years, the lifetime risks (95% confidence interval) for AF were 25.2% (17.1–33.4), 24.2% (20.0–28.9), 27.1% (23.2–31.0), 30.0% (24.3–35.7) and 34.1% (22.4–45.7), for 0, 1, 2, 3, and ≥4 comorbid cardiometabolic disorders among men, respectively. Corresponding risks were 16.3% (6.68–25.9), 20.3% (16.3–24.3), 27.6% (24.1–31.2), 23.6% (17.8–29.4) and 33.3% (16.0–50.2) among women.

Conclusions

We observed a significant combined impact of cardiometabolic disorders on AF risk, most evidently among women. Participants with cardiometabolic multimorbidity had a significantly increased lifetime risk of AF, especially at a young index age.

Funding Acknowledgement

Type of funding sources: None.

Simultaneous absolute protein quantification of seven cytochrome P450 isoforms in rat liver microsomes by LC-MS/MS-based isotope internal standard method

The cytochrome P450 (CYP) enzymes play a pivotal role in drug metabolism. LC-MS/MS-based targeting technology has been applied to the analysis of CYP enzymes, promoting drug development and drug-drug interaction studies. Rat is one of the most commonly used models for drug metabolism assessment, but LC-MS/MS assay quantifying the abundance of CYP enzymes in rats is rarely reported. Herein, an accurate and stable LC-MS/MS based method was developed and validated for the simultaneous quantification of seven major rat CYP isoforms (CYP1A2, 2B1, 2C6, 2C11, 2D1, 2E1, and 3A1) in liver microsomes. The careful optimization of trypsin digestion and chromatography combined with isotope-labeled peptide as internal standard improved the efficiency and accuracy of the analysis. Highly specific surrogate peptides were obtained by a procedure including trypsin digestion for six hours and separated on a Hypersil Gold C18 column (100 × 2.1 mm, 3 μm) using gradient elution for 15 min with a mobile phase of water containing 0.1% formic acid and acetonitrile. In the method validation, linearity, matrix effect, recovery, stability, accuracy, and precision all meet the requirements. Subsequently, this method was applied to detect seven enzymes in rat liver microsomes from four different sources, and the correlation between the abundance and activity of CYP enzymes was further analyzed. The high-throughput detection method provided in this study will provide support for pertinent pharmaceutical research based on rat models.

Lithium chloride promotes neural functional recovery after local cerebral ischaemia injury in rats through Wnt signalling pathway activation

BACKGROUND

Lithium chloride (LiCl) has a significant neuroprotective effect in cerebral ischaemia. However, to date, there is a paucity of evidence on the role of LiCl in neural restoration after brain ischaemia and the signalling pathways involved remain unclear.

MATERIALS AND METHODS

Therefore, to address this gap, the middle cerebral artery occlusion (MCAO) rat model was used to simulate human ischaemia stroke. Male Sprague-Dawley rats were given MCAO for 90 min followed by reperfusion, and Dickkopf-1 (DKK1, 5.0 μg/kg) was administered half an hour before MCAO. Rats were then treated with hypodermic injection of LiCl (2.0 mmol/kg) twice a day for 1 week. After treatment, cognitive impairment was assessed by the Morris water maze test. Neurological deficit score, 2,3,5-triphenyl tetrazolium chloride staining, brain water content, and histopathology were used to evaluate brain damage. Enzyme-linked immunosorbent assay was used to measure oxidative stress damage and inflammatory cytokines. Apoptosis of the hippocampal neurons was tested by western blot. The key factors of Wnt signalling pathway in the ischaemic penumbra were detected by immunofluorescence staining and quantitative real-time polymerase chain reaction.

RESULTS

Current experimental results showed that LiCl treatment significantly improved the impaired spatial learning and memory ability, suppressed oxidative stress, inflammatory reaction, and neuron apoptosis accompanied by attenuating neuronal damage, which subsequently decreased the brain oedema, infarct volume and neurological deficit. Furthermore, the treatment of LiCl activated Wnt signalling pathway. Interestingly, the aforementioned effects of LiCl treatment were markedly reversed by administration of DKK1, an inhibitor of Wnt signalling pathway.

CONCLUSIONS

These results indicate that LiCl exhibits neuroprotective effects in focal cerebral ischaemia by Wnt signalling pathway activation, and it might have latent clinical application for the prevention and treatment of ischaemic stroke.

Equilibration for Electrospray Ionization Mass Spectrometry in Quantitative Analysis

Electrospray ionization mass spectrometry (ESI-MS) is widely used in drug development, therapeutic drug monitoring, and other fields. However, unstable mass spectral signals, especially during the initial stages of instrument operation, plague analysts. Generally, in quantitative experiments, the stability of response can be achieved by running the analytical system for some time. However, the equilibration time required for the responses of different compounds to stabilize has been elusive. To investigate the response stability of the ESI-MS system, 72 compounds with different physicochemical properties were employed on three systems, and flow injection analysis was performed in positive ion mode. With the use of 5.00% (response stable factor, RSF) as the stability limit, about 80% of the compounds were stable within 60 min. Under a 2.00% criterion, the stabilization time was significantly longer. The stabilization time varies with different instruments and physicochemical properties of the compounds. When positive ion detection is performed in an acidic mobile phase, the octanol-water partition coefficient (Log P), molecular weight, and molar volume can all affect the time required to stabilize the response. In general, it is necessary to balance the ESI-MS system for an appropriate time before sample detection, especially for the analysis of compounds with strong hydrophilicity, small molecular weight, or small molar volume under the conditions above.

P-382 Decrease of serum estradiol prior to human chorionic gonadotrophin administration have an impact on live birth in IVF/ICSI cycles

Study question

Whether decrease of serum estradiol prior to human chorionic gonadotrophin administration have an impact on live birth in IVF/ICSI cycles?

Summary answer

The E2 change before the day of hCG administration had significant correlation with live birth. The live birth rate decreased with decreasing serum E2 level.

What is known already

The objective of this study was to assess the effects of a decrease of estradiol (E2) levels on the day of human chorionic gonadotrophin (hCG) administration on in vitro fertilization /intracytoplasmic sperm injection (IVF/ICSI) outcomes, including cycles with long, antagonist and micro stimulus protocols.

Study design, size, duration

In this retrospective cohort study, 1303 patients who received IVF/ICSI non-donor treatment were identified. Patients were divided into two groups according to live birth and the characteristics of IVF/ICSI cycles were compared between groups, including baseline infertility parameters, ovarian stimulation characteristics and embryo laboratory manipulation parameters.

Participants/materials, setting, methods

In this retrospective cohort study, 1303 patients who received IVF/ICSI non-donor treatment were identified. Patients were divided into two groups according to live birth and the characteristics of IVF/ICSI cycles were compared between groups, including baseline infertility parameters, ovarian stimulation characteristics and embryo laboratory manipulation parameters. The multivariate logistic regression model was performed to adjust potential confounders and assess correlation between E2 dynamics before hCG administration and live birth.

Main results and the role of chance

Our results revealed that patients without live birth had higher age (32.13 ± 4.33 vs. 30.21 ± 3.71, P &lt; 0.001) and pervious miscarriages (0.57 ± 0.95 vs. 0.46 ± 0.83, P = 0.0295), while had lower number of oocytes retrieved (8.95 ± 4.69 vs. 12.36 ± 5.54, P &lt; 0.001), day of hCG E2 (8269.53 ± 4104.22 vs. 9580.71 ± 3534.11, P &lt; 0.001) and endometrium thickness (10.37 ± 3.66 vs. 11.50 ± 3.40, P &lt; 0.001) compared with patients with live birth. Additionally, the multivariate logistic regression analysis displayed significant impact of serum E2 change on the live birth, and the achievement of live birth [OR (95%CI) 0.81 (0.71, 0.92), P = 0.001] decreased with the decreasing level of serum E2 before hCG trigger day. Estradiol stratification analyses displayed the OR and 95% CI for the association between △E2 and live birth among patients with different levels of estradiol decline (&lt;25%, 25%–50%, 50%–75%, &gt;75%). Compared with the &lt;25% decline and 25%–50% decline groups, the ORs of 50%–75% and &gt;75% decline groups were 1.66 (95% CI: 1.12-2.45, P = 0.012) and 2.00 (95% CI: 1.39-2.89, P &lt; 0.001), respectively, after adjusting potential confounders.

Limitations, reasons for caution

There was concealment of randomization and blinding of outcome assessments reducing the risk of selection and measurement bias.

Wider implications of the findings

In summary, the E2 change before the day of hCG administration had significant correlation with live birth, and the live birth decreased with the decreasing level of serum E2 before hCG trigger day. The patients with a greater decline in the E2 level more likely to had poor clinical outcomes.

Trial registration number

Chi CTR1900026088

Women-specific risk factors and risk of incident atrial fibrillation in UK Biobank

Funding Acknowledgements

Type of funding sources: None.

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia worldwide and carries a large morbidity and mortality risk. Recent evidence suggests differences in epidemiology and pathophysiology of AF between women and men and underscores a poorer prognosis of AF among women. This calls for further investigation regarding the impact of women-specific risk factors on AF development.

Purpose

To investigate the association between women-specific risk factors and new-onset AF.

Methods

235,191 women (mean [standard deviation] age: 55.7 [8.1] years) free of AF and without a history of hysterectomy and/or bilateral oophorectomy from the UK Biobank were included. Various women-specific risk factors were assessed from 2006 to 2010. Follow-up of new-onset AF occurred through October 2020. Cox proportional hazards analyses were performed to investigate prospective associations between each risk factor and incident AF. Additionally, natural splines were used to identify any potential nonlinear associations.

Results

After a median follow-up of 11.6 (interquartile range: 10.9–12.3) years, 4,629 (2%) women experienced new-onset AF. In fully adjusted models, having experienced irregular menstrual cycle was significantly associated with increased new-onset AF risk [hazard ratio (HR); 95% confidence interval (CI): 1.34; 1.01-1.79]. In addition, nonlinear associations were found between menopausal age, menarcheal age, number of live births, and number of total reproductive years with incident AF. Compared to the reference, early menopause (menopause &lt;45 years of age) or delayed menopause (&gt;60 years) significantly increased risks of incident AF (HR; 95CI: 1.24; 1.10-1.39 and 1.34; 1.01-1.78, respectively). Compared to the reference, both early menarche (menarche ≤11 years) and late menarche (menarche ≥13 years) were associated with AF incidence (HR; 95CI: 1.10; 1.00-1.21 and 1.08; 1.00-1.17, respectively). Compared to women with one or two children, having no children (HR; 95CI: 1.13; 1.04-1.24), or more than six children (HR; 95%CI: 1.67; 1.03-2.70) were associated with higher AF risks. Having reproductive years ≤20 years was significantly associated with incident AF (HR; 95CI: 1.74; 1.07-2.86).

Conclusions

Having experienced early or delayed menopause, early or late menarche, or irregular menstrual cycles conferred higher risks of incident AF among women in the UK Biobank. Interestingly, both nulliparity and multiparity, compared to having one or two children, were associated with an increased AF risk. Our results highlight the importance of knowledge regarding the reproductive history of women in devising screening strategies for AF prevention.

Fate of thiamethoxam from treated seeds in mesocosms and response of aquatic invertebrate communities

Thiamethoxam is a neonicotinoid insecticide widely applied in the Canadian Prairies. It has been detected in surface waters of agro-ecosystems, including wetlands, but the potential effects on non-target invertebrate communities in these wetlands have not been well characterized. In an effort to understand better the fate of thiamethoxam in wetlands and the response of invertebrates (zooplankton and emergent insects), model systems were used to mimic wetland flooding into planted fields. Outdoor mesocosms were treated with a single application of thiamethoxam-treated canola seeds at three treatment levels based on a recommended seeding rate (i.e., 6 kg/ha; 1×, 10×, and 100× seeding rate) and monitored over ten weeks. The mean half-life of thiamethoxam in the water column was 6.2 d. There was no ecologically meaningful impact on zooplankton abundances or community structure among treatments. Statistically significant differences were observed in aquatic insect abundance between control mesocosms and the two greatest thiamethoxam treatments (10× and 100× seeding rate). The observed results indicate exposure to thiamethoxam at environmentally relevant concentrations likely does not represent a significant ecological risk to abundance and community structure of wetland zooplankton and emergent insects.

Multidimensional, High Precision Measurements of Beam Single Spin Asymmetries in Semi-inclusive π^{+} Electroproduction off Protons in the Valence Region

High precision measurements of the polarized electron beam-spin asymmetry in semi-inclusive deep inelastic scattering (SIDIS) from the proton have been performed using a 10.6 GeV incident electron beam and the CLAS12 spectrometer at Jefferson Lab. We report here a high precision multidimensional study of single π^{+} SIDIS data over a large kinematic range in Bjorken x, fractional energy, and transverse momentum of the hadron as well as photon virtualities Q^{2} ranging from 1-7  GeV^{2}. In particular, the structure function ratio F_{LU}^{sinϕ}/F_{UU} has been determined, where F_{LU}^{sinϕ} is a twist-3 quantity that can reveal novel aspects of emergent hadron mass and quark-gluon correlations within the nucleon. The data's impact on the evolving understanding of the underlying reaction mechanisms and their kinematic variation is explored using theoretical models for the different contributing transverse momentum dependent parton distribution functions.

Predictive Value of Geriatric Nutritional Risk Index in Older Adult Cancer Patients

BACKGROUND AND AIMS

To compare the association of geriatric nutritional risk index (GNRI) and controlling nutritional status (CONUT) scores with malnutrition, and to study their association with clinical outcomes in older adult cancer patients.

METHODS

This retrospective analysis was conducted on 854 older adult cancer patients collected from 34 hospitals in 18 cities in China between June and September 2014. Anthropometric and hematological examination results at admission were collected, and subjective global assessment was used. Clinical outcomes, such as complications, length of hospital stays, and hospital costs, were recorded. Receiver operating characteristic curves were used to evaluate the accuracy of the two nutritional assessment tools for malnutrition. The association between GNRI and CONUT score and clinical outcomes was analyzed using the chi-square test, t-test, or rank sum test.

RESULTS

Among 854 patients with cancer, the prevalence of malnutrition was 42.7%. Compared with subjective global assessment, the GNRI had a significantly higher accuracy than the CONUT score in predicting malnutrition (area under the curve 0.704, 95% confidence interval, 0.658 - 0.750, P < 0.001). The GNRI was significantly associated with the occurrence of complications (χ2 = 4.985, P = 0.026), and low GNRI (≤98) was associated with a longer length of hospital stay (t = -2.179, P = 0.030).

CONCLUSIONS

The GNRI may be used to assess malnutrition in older adult cancer patients and can predict poor clinical outcomes in these patients.

The global prevalence of sexual violence against pregnant women: a systematic review and meta-analysis

When committed against pregnant women, sexual violence may have adverse health consequences for both the mother and the unborn child. To date, no studies have systematically summarized the global prevalence of sexual violence against pregnant women. We conducted a comprehensive search of PubMed, Embase and Web of Science from inception dates to January 2021 for studies reporting the prevalence of sexual violence against pregnant women. Prevalence was estimated using a random-effects meta-analysis. Heterogeneity was evaluated using the I² statistic. Differences by study level characteristics were estimated through subgroup analysis and meta-regression. A total of 10 cross-sectional studies (a total of 8,439 participants) were included. The pooled proportion of sexual violence was 0.31 (95% CI: 0.22-0.40). Subgroup analyses showed higher prevalence of sexual violence against pregnant women in the 2010-2019 period (0.35, 95% CI0.15-7.53) and developing countries (0.32, 95% CI0.19-0.45). Almost one in three (31%) pregnant women around the world has been a victim of sexual violence in their lifetime. Sexual violence against pregnant women continues to be a major public health challenge. The global prevalence of sexual violence against pregnant women warrants the collective attention of the entire society.

Standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery for sacrocolpopexy

We describe the standard practice of presacral exposure during transvaginal natural orifice transluminal endoscopic surgery (vNOTES) for sacrocolpopexy in women with uterine prolapse. In this video, we demonstrate the key techniques: identifying the right hypogastric nerve (rHN) before opening the pelvic peritoneum; removing the fat and loose connective tissue along the rHN to expose the presacral fascia; incising the presacral fascia to reach the presacral space to expose the middle sacral vasculature and the anterior longitudinal ligament (ALL) of the first sacral vertebra (S1) below the promontory; attaching the mesh to the ALL to avoid vessel injury; and completing the peritonealisation.

Study on a new manner of the magnetization switching actuated by a unidirectional pulse current

A new writing scheme with a unidirectional pulse current is proposed for spin transfer torque (STT) based magnetic random-access memory (MRAM). To investigate the feasibility of the writing scheme, bilayered nano-pillars composed of a soft layer with small in-plane shape anisotropy and a hard layer with either large perpendicular anisotropy (PMA) or in-plane anisotropy (IMA) are designed and their switching behaviors are studied. It is found that in either type of bilayered nano-pillars, with the aid of the attached hard layer, the magnetization of the soft layer can be switched back and forth under a unidirectional pulse current. In an IMA/IMA nano-pillar, the magnetization of the free layer (FL) can achieve excellent alignment, which is in contrast to the IMA/PMA nano-pillar. By optimizing the dimensions and magnetic parameters of the IMA/IMA nano-pillar, a decently low switching current density (4.3 × 10¹¹A m^-2) and ultrashort switching time (<1 ns) can be reached. Based on these results, the unidirectional writing scheme is practical if an IMA/IMA bilayer is used to replace the FL in a magnetic tunnel junction. Considering that a unidirectional writing scheme can enable the application of materials with high spin polarization such as half metals, and avoid the injection of writing current into junction using a special design, it may be very promising for STT-MRAM.

Imaging-based body fat depots and new-onset atrial fibrillation in general population

Background

Obesity is a well-established risk factor for incident atrial fibrillation (AF). Whether different body fat depots differentially associate with AF development remains largely unknown.

Purpose

We aimed to investigate the associations between various body fat depots and the risk of new-onset AF among middle-aged and elderly individuals from general population.

Methods

In the prospective population-based cohort study, body composition was assessed using dual-energy X-ray absorptiometry (DXA) and total body mass, lean mass, fat mass, android and gynoid fat were analyzed (N=3468). Liver fat and epicardial fat were assessed using computed tomography (CT) (N=2145). A body fat score was defined by adding tertiles of each fat depot. All participants were followed for the occurrence of AF until 1st Jan. 2014. Principle component analysis was conducted to identify body fat distribution patterns. Time-to-event analyses were performed using Cox proportional hazards regression analysis. Hazard ratios (HR) and 95% confidence-intervals (95% CI), adjusted for cardiovascular risk factors, were calculated.

Results

Mean (standard deviation) of age for participants in DXA study and CT study was 74.42 (6.85) and 68.66 (6.41) years, respectively. AF incidence rate was 13.1 per 1000 person-years during a median follow-up time of 9.62 years. In the adjusted model, fat mass (HR; 95% CI: 1.33; 1.05–1.68), lean mass (1.40; 1.15–1.72), gynoid fat mass (1.36; 1.12–1.65), and total body mass (1.51; 1.21–1.89) were significantly associated with new-onset AF. Of note, android-to-gynoid fat ratio was inversely associated with incident AF (HR; 95% CI: 0.81; 0.70–0.94). Larger body fat score was associated with increased risk of incident AF (P for trend &lt;0.01). Two fat distribution patterns were identified. Adherence to the fat- and gynoid fat- pattern (P for trend = 0.035), but not muscle- and visceral fat- pattern (P for trend = 0.35), was significantly associated with larger risk of new-onset AF.

Conclusions

Various body fat depots were associated with new-onset AF. Larger values of total body mass carried the highest risk for incident AF. The inverse association between android to gynoid fat ratio with AF presents a novel finding. A significant dose-response relationship between body fat accumulation and risk of new-onset AF was observed, implying a collective impact of fat depots on AF development. Findings also suggest that various fat depots, characterized by different fat distribution patterns, may exert differential combined effect on the risk of incident AF.

Funding Acknowledgement

Type of funding sources: None. Fat depots and atrial fibrillation

Constipation is associated with worse prognosis of thrombolytic AIS: a single-center prospective study

Background and purpose

Previous clinical studies have found that constipation was associated with the prognosis of ischemic stroke patients. This information may provide new ideas for thrombolytic AIS (acute cerebral arterial thrombosis) patients' short-term prognostic assessment. Our study was designed to investigate the risk factors of constipation and its association with the prognosis in thrombolytic AIS patients.

Methods

The prospective cohort study included 97 AIS patients treated with intravenous thrombolysis. Three days without defecation in thrombolytic patients was recorded as constipation in clinic. The risk factors for constipation included demographics, clinical characteristics, laboratory parameters and partial treatments. Scores of NIHSS and mRS and length of stay (LOS) in ICU and hospital were used to evaluate the effect of constipation on patients' neurological function and short-term prognosis.

Results

The incidence of constipation was 49.48% in the first three days after intravenous thrombolysis. The use of stomach tube and antibiotics made patients more prone to constipation (odds ratio OR: 5.01, 95% CI: 2.04–12.32, P=0.000; odds ratio: 6.06, 95% CI: 2.35–15.61, P=0.000). The occurrence of constipation resulted in significantly longer ICU and hospital LOS (2.29±1.63 versus 4.75±4.22, P=0.000; 11.08±10.01 versus 15.73±12.36, P=0.044). Moreover, constipation worsened the thrombolytic AIS patients' short-term neurological recovery (mRS at 3 months: 1.53±1.72 versus 2.41±1.92, P=0.02). Oral probiotics for constipation during hospitalization not only prolonged patients' stay in the ICU (2.91±2.28 versus 6.44±4.88, P=0.003), but also resulted in poorer short-term neurological functional outcomes (mRS at 3 months: 1.57±1.53 versus 3.26±1.91, P=0.002).

Conclusions

The occurrence of constipation in the first three days was associated with the longer ICU and hospital stay and a worse short-term prognosis, suggesting that constipation may be a predictor of thrombolytic AIS patients' prognosis. Further studies of constipation and its appropriate therapy strategy are needed to solve the plight of thrombolytic AIS with constipation.

Funding Acknowledgement

Type of funding sources: None.

Distribution and risk profile of atrial fibrillation patterns among women and men from the general population

Background

In a clinical setting, atrial fibrillation (AF) subgroups are defined, including paroxysmal, persistent, and permanent AF. These subgroups differ in terms of clinical characteristics, management strategy, and long-term outcomes. Application of clinical classifications in population-based settings is challenging as they are based on the duration of symptoms, recurrence, and treatment.

Purpose

We aim to develop an objective and standardized classification for AF patterns in the general population and examine the associated cardiovascular risk profiles and outcomes for the identified AF patterns.

Methods

Participants with only one reported AF episode were categorized as single-documented AF, if at least two separate AF episodes were reported as multiple-documented AF and as longstanding persistent AF if at least two consecutive ECG's at the research center showed AF, not followed by an ECG showing sinus rhythm. We fitted mixed effect models with age as time scale to characterize sex-specific cardiovascular risk factor trajectories preceding each AF pattern. We further used Cox proportional hazard modelling to describe the risk of coronary heart disease (CHD), heart failure (HF), stroke, and all-cause mortality following AF.

Results

We included 14,620 men and women aged ≥45 years. 1137 participants were categorized as single-documented AF, 208 as multiple-documented AF, and 57 as longstanding persistent AF. We identified significant differences in the preceding trajectories of weight, body mass index, systolic blood pressure, diastolic blood pressure, waist circumference, hip circumference, and waist-hip ratio with various AF patterns. In general, both men and women with persistent-elevated levels of these risk factors were prone to longstanding persistent AF.

AF was associated with a large risk for subsequent CHD, HF, stroke, and mortality in the general population. Among the different AF patterns, single-documented AF conferred the largest risk of CHD [hazard ratio, 95% confidence interval: 1.92 (1.19–3.03)] and mortality [1.70 (1.41–2.07)] as compared to multiple-documented AF, and as compared to longstanding persistent AF [1.45 (0.72–2.90) and 3.66 (2.25–5.95), respectively].

Conclusion

We developed a classification for AF patterns within a general population. We identified differences in risk factor trajectories preceding each AF pattern, which implies differences in pathophysiological mechanisms underlying AF. Participants with single-documented AF showed worse prognosis than those with multiple AF episodes. This might be due to the subgroup definition, since participants should live for a longer period of time to be categorized in the multiple-documented AF and longstanding persistent AF groups. This can also imply that participants suffering from multiple AF episodes are more frequently monitored, and treated for other risk factors. However, this could also suggest that singular AF episodes are not as innocent as commonly thought.

Funding Acknowledgement

Type of funding sources: Public hospital(s). Main funding source(s): - Erasmus MC Mrace grant. - Netherlands Organization for the Health Research and Development (ZonMw) Figure 1Figure 2. Progosis of various AF patterns

Prognostic nutrition index predicts outcomes in critically ill stroke patients: a database-based cohort study

Background

Although there are many indicators to assess nutritional status, a more comprehensive and objective indicator is still needed in clinical practice. In this study, we evaluated the relationship between the prognostic nutritional index (PNI) and clinical outcomes in patients with critically ill stroke.

Methods

Subjects who were diagnosed as stroke in the Beth Israel Deaconess Medical Center between 2001 and 2012 were identified from the Medical Information Mart for Intensive Care (MIMIC) III database. PNI was calculated as 10 × serum albumin (g/dL) + 0.005 × total lymphocyte count (per mm3). The multivariate logistic regression and the Cox regression analysis were performed to assess the impact of PNI on 3-month and 4-year mortality in stroke patients.

Results

A total of 624 subjects were included in this study. Compared with the high-PNI group, those in the Low PNI group had lower body mass index (BMI), hemoglobin, neutrophil count, lymphocyte count and albumin. On the contrary, Age, Blood urea nitrogen (BUN), Creatinine (Cre), simplified acute physiologic scoreII (SAPSII) score and sequential organ failure assessment (SOFA) score of the low PNI group were higher than the high PNI group. After adjusting for other confounders, PNI was independently associated with 3-month mortality (adjusted odds ratio = 1.910; 95% confidence interval, 1.244–2.933; P=0.003). By the Kaplan-Meier analysis, patients in the low PNI group presented significantly shorter survival time and higher death rate. The Cox regression model indicated low PNI as an independent risk factor of 4-year all-cause mortality of stroke patients (hazard ratio = 1.824; 95% CI, 1.340–2.483; P&lt;0.001).

Conclusions

Low PNI is independently associated with short-term and long-term prognosis in patients with critically ill stroke.

Funding Acknowledgement

Type of funding sources: None.

Trajectories of metabolic risk factors and risk of new-onset atrial fibrillation among men and women

Background

Atrial fibrillation (AF) is the most common cardiac arrhythmia with major public health impact. Obesity and hypertension are among the most important risk factors to AF development. The link between AF and its pathogenetic factors are complex and comprehensive assessment of the impact of various long-term trajectories of anthropometric measures and blood pressure on incident AF among men and women is sparse.

Purpose

To investigate sex-specific trajectories of various anthropometric measures and blood pressure at population level, and further assess the impact of these trajectories on incident AF.

Methods

We included 5263 participants (mean age 72.1 years) with available repeated assessments measured 2 to 4 times for weight, body mass index (BMI), hip circumference (HC), waist circumference (WC), waist-to-hip ratio (WHR), systolic blood pressure (SBP), diastolic blood pressure (DBP), pulse pressure (PP) and mean arterial pressure (MAP). Latent class linear mixed model with age as the time scale were fitted to identify the potential various classes in each risk factor. Cox proportional hazards regression models were used to assess the association between risk factors' trajectories and risk of new-onset AF, with the most favorable trajectory as a reference. Models were adjusted for traditional cardiovascular risk factors.

Results

2159 (41.0%) of all participants were men. Median follow-up time was 9.76 years during which the incidence rate of AF was 16.2 per 1000 person-years for men, and 11.3 per 1000 person-years for women. In full-adjusted model, various trajectories of BMI, HC, and MAP were significantly associated with incident AF among men, and trajectories of weight, BMI, WC, HC, SBP, PP and MAP were significantly associated with incident AF among women. For BMI, persistent-increasing BMI trajectory carried the highest risk for AF with hazard ratio (HR) and 95% confidence interval (95% CI) of 1.39 (1.05–1.85) in men and 1.60 (1.19–2.15) in women. Also, persistently increasing trajectories of weight [1.69 (1.20–2.37)], WC [1.39 (1.04–1.86)] and HC [1.56 (1.05–2.34)] among women conferred the largest risks. For SBP, the persistently hypertensive trajectory carried the largest risk for AF among women [2.06 (1.25–3.39)], while intensively increasing SBP trajectory conferred the largest risk among men [1.34 (0.89–2.02)], albeit non-significant. Similar associations were observed for MAP among men and women; associated risks were 1.77 (1.25–2.51) for the persistent-hypertensive trajectory in women and 1.64 (1.16–2.33) for the intensive-increasing trajectory in men.

Conclusions

Various trajectories of metabolic risk factors were associated with new-onset AF among men and women. Sex-specific associations between SBP and MAP with AF could imply the differential long-term impact of vascular function on AF development among men and women. This highlights the importance of sex-specific preventive strategies for AF in general population.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Gender and Prevention grant, ZonMwCSC scholarship for PhD research