Plaque Ruptures Are Related to High Plaque Stress and Strain Conditions: Direct Verification by Using In Vivo OCT Rupture Data and FSI Models.

BACKGROUND: While it has been hypothesized that high plaque stress and strain may be related to plaque rupture, its direct verification using in vivo coronary plaque rupture data and full 3-dimensional fluid-structure interaction models is lacking in the current literature due to difficulty in obtaining in vivo plaque rupture imaging data from patients with acute coronary syndrome. This case-control study aims to use high-resolution optical coherence tomography-verified in vivo plaque rupture data and 3-dimensional fluid-structure interaction models to seek direct evidence for the high plaque stress/strain hypothesis. METHODS: In vivo coronary plaque optical coherence tomography data (5 ruptured plaques, 5 no-rupture plaques) were acquired from patients using a protocol approved by the local institutional review board with informed consent obtained. The ruptured caps were reconstructed to their prerupture morphology using neighboring plaque cap and vessel geometries. Optical coherence tomography-based 3-dimensional fluid-structure interaction models were constructed to obtain plaque stress, strain, and flow shear stress data for comparative analysis. The rank-sum test in the nonparametric test was used for statistical analysis. RESULTS: Our results showed that the average maximum cap stress and strain values of ruptured plaques were 142% (457.70 versus 189.22 kPa; P=0.0278) and 48% (0.2267 versus 0.1527 kPa; P=0.0476) higher than that for no-rupture plaques, respectively. The mean values of maximum flow shear stresses for ruptured and no-rupture plaques were 145.02 dyn/cm2 and 81.92 dyn/cm2 (P=0.1111), respectively. However, the flow shear stress difference was not statistically significant. CONCLUSIONS: This preliminary case-control study showed that the ruptured plaque group had higher mean maximum stress and strain values. Due to our small study size, larger scale studies are needed to further validate our findings.

The Differences of Quantitative Flow Ratio in Coronary Artery Stenosis with or without Atrial Fibrillation.

Quantitative flow ratio (QFR) is a new method for the assessment of the extent of coronary artery stenosis. But it may be obscured by the cardiac remodeling and abnormal blood flow of the coronary artery when encountering atrial fibrillation (AF). The present study aimed to examine the impact of these changed structures and blood flow of coronary arteries on QFR results in AF patients. Methods and Results. We evaluated QFR in 223 patients (112 patients with AF; 111 non-AF patients served as controls) who had undergone percutaneous coronary intervention (PCI) due to severe stenoses in coronary arteries. QFR of the target coronary was determined according to the flow rate of the contrast agent. Results showed that AF patients had significantly higher QFR values than control (0.792 ± 0.118 vs. 0.685 ± 0.167, p < 0.001). We further analyzed local QFR around the stenoses (0.858 ± 0.304 vs. 0.756 ± 0.146, p=0.002), residual QFR (0.958 ± 0.055 vs. 0.929 ± 0.093, p=0.005), and index QFR (0.807 ± 0.108 vs. 0.713 ± 0.152, p < 0.001) in these two groups of patients with and without AF. Further analysis revealed that QFR in AF patients was negatively correlated with coronary flow velocity (R = -0.22, p=0.02) and area of stenosis (R = -0.70, p < 0.001) but positively correlated with the minimum lumen area (MLA) (R = 0.47, p < 0.001). Conclusion. AF patients with coronary artery stenosis have higher QFR values, which are associated with decreased blood flow velocity, smaller stenosis, and larger MLA in AF patients upon cardiac remodeling.

Adsorption and mechanism study for phenol removal by 10% CO2 activated bio-char after acid or alkali pretreatment.

The development of an efficient bio-char used to remove phenol from wastewater holds great importance for environmental protection. In this work, wheat straw bio-char (BC) was acid-washed by HF and activated at 900 °C with 10% CO2 to obtain bio-char (B-Ⅲ-0.1D900). Adsorption experiments revealed that B-Ⅲ-0.1D900 achieved a remarkable phenol removal efficiency of 90% within 40 min. Despite its relatively low specific surface area of 492.60 m2/g, it exhibited a high maximum adsorption capacity of 471.16 mg/g. Furthermore, B-Ⅲ-0.1D900 demonstrated a good regeneration capacity for at least three cycles (90.71%, 87.54%, 84.36%). It has been discovered that HF washing, which removes AAEM and exposes unsaturated functional groups, constitutes one of the essential prerequisites for enhancing CO2 activation efficiency at high temperatures. After 10% CO2 activation, the mesoporous structure exhibited substantial development, facilitating enhanced phenol infiltration into the pores when compared to untreated BC. The increased branching of the bio-char culminated in a more complete aromatic system, which enhances the π-π forces between the bio-char and the phenol. The presence of tertiary alcohol structure enhances the hydrogen bonding forces, thereby promoting intermolecular multilayer adsorption of phenol. With the combination of various forces, B-Ⅲ-0.1D900 has a good removal capacity for phenol. This work provides valuable insights into the adsorption of organic pollutants using activated bio-char.

Effects of PCSK9 Inhibition on Coronary Atherosclerosis Regression of Nontarget Lesions after Primary Percutaneous Coronary Intervention in Acute Coronary Syndrome Patients.

Aims: To evaluate the regression of coronary atherosclerosis with proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibition in acute coronary syndrome (ACS) patients following primary percutaneous coronary intervention (PPCI). Methods and Result. We examined 40 nontarget lesions in 17 ACS patients who underwent PPCI and were treated with PCSK9 inhibitors. At 1 year, total cholesterol, low-density lipoprotein cholesterol (LDL-C), and atherogenic index (AI) decreased significantly by 2.5 mmol/L, 2.01 mmol/L, and 1.86, respectively. On quantitative coronary angiography, treatment with PCSK9 inhibitors reduced significantly the atherosclerotic area stenosis in nontarget lesions (61.18 ± 14.55 at baseline vs. 52.85 ± 15.51 at 1 year, P < 0.001). Conclusions: After 1 year of PCSK9 inhibition treatment for ACS patients, the area stenosis of non-TLR was considerably reduced.

Spontaneous left main coronary artery dissection occurred in a young male: a case report and review of literature.

BACKGROUND: Spontaneous coronary artery dissection (SCAD) is now recognized as an important cause of acute coronary syndrome (ACS), which is thought to be more prevalent in women. However, the male patients, on the other hand, cannot be easily ignored. CASE PRESENTATION: A 26-year-old male suffered from SCAD that occurred in the left main coronary artery (LMCA) and a secondary acute myocardial infraction (AMI). Coronary CT angiography and coronary angiography (CAG) revealed aneurysms in the LMCA and right coronary artery (RCA), as well as a total occlusion in the proximal branch of the left anterior descending artery (LAD). Along with drug therapy, coronary artery bypass graft (CABG) surgery was recommended, and the patient has been symptom-free for one year. CONCLUSION: We report a case of spontaneous left main coronary artery dissection that occurred in a young male. The necessity of identifying typical imaging features and following up patients with SCAD for life to reduce the risk of fatal cardiac complications cannot be overstated.

Selective Recovery of Palladium (II) from Metallurgical Wastewater Using Thiadiazole-Based Chloromethyl Polystyrene-Modified Adsorbent.

Selective adsorption of palladium from metallurgical wastewater containing Pt (IV), Rh (III), Ca2+, Cu2+, Fe3+, Ni2+, Pb2+, V3+, and Ti4+ has tremendous economic and environmental benefits. In this paper, a novel thiadiazole-based chloromethyl polystyrene-modified adsorbent, viz. 2, 5-bis-polystyrene-1,3,4-thiadiazole (PS-DMTD), was synthesized using chloromethyl polystyrene as the backbone. The experimental results show that PS-DMTD can selectively separate Pd (II) from metallurgical wastewater in a one-step adsorption process. The calculated saturation adsorption capacity of PS-DMTD for Pd (II) was 176.3 mg/g at 25 °C. The separation factors of ßPd (II)/Mn+ (Mn+: Pt (IV), Rh (III), Ca2+, Cu2+, Fe3+, Ni2+, Pb2+, V3+, and Ti4+) were all higher than 1 × 104. FT-IR, XPS, and single-crystal X-ray diffraction showed that the adsorption of Pd (II) to PS-DMTD was primarily through a coordination mechanism. Density functional theory (DFT) calculations revealed that the other base metal ions could not coordinate with the PS-DMTD. Pt (IV) could not be adsorbed to PS-DMTD due to its strong chlorophilicity. Furthermore, Rh (III) existed as a polyhydrate, which inhibited Rh (III) diffusion toward the positively charged absorption sites on the PS-DMTD. These results highlight that PS-DMTD has broad application prospects in the recovery of Pd (II) from metallurgical wastewater.

Facultative symbiosis with a saprotrophic soil fungus promotes potassium uptake in American sweetgum trees.

Several species of soil free-living saprotrophs can sometimes establish biotrophic symbiosis with plants, but the basic biology of this association remains largely unknown. Here, we investigate the symbiotic interaction between a common soil saprotroph, Clitopilus hobsonii (Agaricomycetes), and the American sweetgum (Liquidambar styraciflua). The colonized root cortical cells were found to contain numerous microsclerotia-like structures. Fungal colonization led to increased plant growth and facilitated potassium uptake, particularly under potassium limitation (0.05 mM K+ ). The expression of plant genes related to potassium uptake was not altered by the symbiosis, but colonized roots contained the transcripts of three fungal genes with homology to K+ transporters (ACU and HAK) and channel (SKC). Heterologously expressed ChACU and ChSKC restored the growth of a yeast K+ -uptake-defective mutant. Upregulation of ChACU transcript under low K+ conditions (0 and 0.05 mM K+ ) compared to control (5 mM K+ ) was demonstrated in planta and in vitro. Colonized plants displayed a larger accumulation of soluble sugars under 0.05 mM K+ than non-colonized plants. The present study suggests reciprocal benefits of this novel tree-fungus symbiosis under potassium limitation mainly through an exchange of additional carbon and potassium between both partners.

Clinical characteristics of COVID-19 in children compared with adults in Shandong Province, China.

AIMS AND BACKGROUND: The COVID-19 outbreak spread in China and is a threat to the world. We reported on the epidemiological, clinical, laboratory, and radiological characteristics of children cases to help health workers better understand and provide timely diagnosis and treatment. METHODS: Retrospectively, two research centers' case series of 67 consecutive hospitalized cases including 53 adult and 14 children cases with COVID-19 between 23 Jan 2020 and 15 Feb 2020 from Jinan and Rizhao were enrolled in this study. Epidemiological, clinical, laboratory, and radiological characteristics of children and adults were analyzed and compared. RESULTS: Most cases in children were mild (21.4%) and conventional cases (78.6%), with mild clinical signs and symptoms, and all cases were of family clusters. Fever (35.7%) and dry cough (21.4%) were described as clinical manifestations in children cases. Dry cough and phlegm were not the most common symptoms in children compared with adults (p = 0.03). In the early stages of the disease, lymphocyte counts did not significantly decline but neutrophils count did in children compared with adults (p = 0.02). There was a lower level of CRP (p = 0.00) in children compared with adults. There were 8 (57.1%) asymptomatic cases and 6 (42.9%) symptomatic cases among the 14 children cases. The age of asymptomatic patients was younger than that of symptomatic patients (p = 0.03). Even among asymptomatic patients, 5 (62.5%) cases had lung injuries including 3 (60%) cases with bilateral involvement, which was not different compared with that of symptomatic cases (p = 0.58, p = 0.74). CONCLUSIONS: The clinical symptoms of children are mild, there is substantial lung injury even among children, but that there is less clinical disease, perhaps because of a less pronounced inflammatory response, and that the occurrence of this pattern appears to inversely correlate with age.

One Step Interface Activation of ZnS Using Cupric Ions for Mercury Recovery from Nonferrous Smelting Flue Gas.

The flue gases with high concentration of mercury are often encountered in the nonferrous smelting industries and the treatment of mercury-containing wastes. To recover mercury from such flue gases, sorbents with enough large adsorption capacity are required to capture and enrich mercury. ZnS is a cheap and readily prepared material, and even can be obtained from its natural ores. In this work, a simple controllable oxidation method-soaking in cupric solution-was developed to improve the interfacial activity of ZnS and its natural ores for Hg0 adsorption. The gaseous Hg0 adsorption capacity of ZnS was enhanced from 0.3 to 3.6 mg·g-1 after such treatment. Further analysis indicated that a new interface rich in S1- ions was formed and provided sufficient active sites for the chemical adsorption of Hg0. In addition, the cyclic Hg0 adsorption and recovery experiments demonstrated that the adsorption performance of spent activated-ZnS was recovered after reactivating sorbents with Cu2+, indicating the recovery of activated interface. Meanwhile, the high concentration of adsorbed mercury at the surface can be collected using a thermal treatment method. Utilization of raw materials from a zinc production process provides a promising and cost-effective method for removing and recovering mercury from nonferrous smelting flue gas.

Identification of PAN2 by quantitative proteomics as a leucine-rich repeat-receptor-like kinase acting upstream of PAN1 to polarize cell division in maize.

Mechanisms governing the polarization of plant cell division are poorly understood. Previously, we identified pangloss1 (PAN1) as a leucine-rich repeat-receptor-like kinase (LRR-RLK) that promotes the polarization of subsidiary mother cell (SMC) divisions toward the adjacent guard mother cell (GMC) during stomatal development in maize (Zea mays). Here, we identify pangloss2 (PAN2) as a second LRR-RLK promoting SMC polarization. Quantitative proteomic analysis identified a PAN2 candidate by its depletion from membranes of pan2 single and pan1;pan2 double mutants. Genetic mapping and sequencing of mutant alleles confirmed the identity of this protein as PAN2. Like PAN1, PAN2 has a catalytically inactive kinase domain and accumulates in SMCs at sites of GMC contact before nuclear polarization. The timing of polarized PAN1 and PAN2 localization is very similar, but PAN2 acts upstream because it is required for polarized accumulation of PAN1 but is independent of PAN1 for its own localization. We find no evidence that PAN2 recruits PAN1 to the GMC contact site via a direct or indirect physical interaction, but PAN2 interacts with itself. Together, these results place PAN2 at the top of a cascade of events promoting the polarization of SMC divisions, potentially functioning to perceive or amplify GMC-derived polarizing cues.

The efficacy and safety of entecavir in patients with chronic hepatitis B- associated liver failure: a meta-analysis.

BACKGROUND: The effectiveness of nucleoside analogue (NA) treatment in patients with chronic hepatitis B (CHB) -associated liver failure is still controversial. Severe lactic acidosis has been reported during entecavir (ETV) treatment in patients with impaired liver function. AIM: To investigate the rescuing efficacy and safety of ETV in patients with CHB-associated liver failure. MATERIAL AND METHODS: A literature search was carried out to collect articles dated up to December, 2013 on ETV therapy for patients with CHB-associated liver failure. Risk ratio (RR) and mean difference (MD) were used to measure the effects. Survival rate was used as the primary efficacy measure. The safety of ETV was assessed. RESULTS: Six randomized controlled trials were selected. The overall analysis revealed ETV significantly improved survival at 4 weeks (RR = 1.35; 95% CI [1.16, 1.57]; p < 0.0001), 8 weeks (RR = 1.33; 95% CI [1.07, 1.64]; p = 0.009), 12 weeks (RR = 1.68; 95% CI [1.24, 2.28]; p = 0.0008). Pooled data also showed beneficial effects of antiviral therapy compared with control for HBV DNA negative change (RR = 5.35; 95% CI [2.06, 13.88]; p = 0.0006), TBIL and PTA improvement (TBIL: MD = -69.36; 95% CI [-134.37, -4.36]; p = 0.04. PTA: MD = 16.26; 95% CI [8.59, 23.94]; p < 0.0001). No adverse effect was identified in the examined studies. CONCLUSION: Our results showed that antiviral therapy with ETV improved the short-term survival of patients with CHB-associated liver failure. In addition, ETV was well tolerated during the treatment period. Further studies are still needed to strengthen these results.

Prognostic value of a disintegrin and metalloproteinase Domain-8 in heart failure.

Background: Heart failure (HF) is a severe disease threatening people's health. The aim of this study is to find a significant biomarker inducive to predicting the prognosis of HF. Methods: GSE135055 and GSE161472 datasets were reanalyzed for exploring key genes related to HF. This single-center, prospective, observational cohort study enrolled 298 patients with or without HF from the Cardiology Department of Zhongda Hospital. Levels of ADAM8 were measured using ELISA kits. Major adverse cardiovascular events (MACEs) were defined as the composite end points of the first occurrence of rehospitalization because of HF or cardiac-related death during one-year follow-up. Results: (1) Bioinformatics analysis showed that ADAM8 was a key gene in HF via mainly regulating the mechanisms of extracellular matrix (ECM) organization. (2) Levels of ADAM8 were significantly increased in the HF group, compared to the non-failing (NF) group (p < 0.001), especially in patients with HFrEF (p < 0.05), and HFmEF (p < 0.05). The prevalence of HF in the high ADAM8 group (≧472.916 pg/mL) was significantly higher than in the low ADAM8 group (<472.916 pg/mL) (41.95 % vs 30.54 %, p < 0.01). (3) Correlation analysis revealed that ADAM8 was negatively correlated to the left ventricular ejection fraction (LVEF) (r = -0.272, p < 0.001). ROC analysis showed that the AUC of ADAM8 in predicting HF and predicting the MACE were 0.701 (p < 0.0001) and 0.683 (p < 0.0001), respectively. (4) Logistic and Cox regression both indicated that high ADAM8 expression can predict adverse prognosis of HF. Conclusions: ADAM8 may be a risk factor for HF, especially in cases of HFrEF and HFmEF. High ADAM8 expression in plasma was related to the decreased heart function, and can predict the adverse prognosis of HF.

Impact of residual stress on coronary plaque stress/strain calculations using optical coherence tomography image-based multi-layer models.

Introduction: Mechanical stress and strain conditions play an important role in atherosclerosis plaque progression, remodeling and potential rupture and may be used in plaque vulnerability assessment for better clinical diagnosis and treatment decisions. Single layer plaque models without residual stress have been widely used due to unavailability of multi-layer image segmentation method and residual stress data. However, vessel layered structure and residual stress have large impact on stress/strain calculations and should be included in the models. Methods: In this study, intravascular optical coherence tomography (OCT) data of coronary plaques from 10 patients were acquired and segmented to obtain the three-layer vessel structure using an in-house automatic segmentation algorithm. Multi- and single-layer 3D thin-slice biomechanical plaque models with and without residual stress were constructed to assess the impact of residual stress on stress/strain calculations. Results: Our results showed that residual stress led to a more uniform stress distribution across the vessel wall, with considerable plaque stress/strain decrease on inner wall and increase on vessel out-wall. Multi-layer model with residual stress inclusion reduced inner wall maximum and mean plaque stresses by 38.57% and 59.70%, and increased out-wall maximum and mean plaque stresses by 572.84% and 432.03%. Conclusion: These findings demonstrated the importance of multi-layer modeling with residual stress for more accurate plaque stress/strain calculations, which will have great impact in plaque cap stress calculation and plaque rupture risk assessment. Further large-scale studies are needed to validate our findings.

Response of rice nitrogen physiology to high nighttime temperature during vegetative stage.

The effects of night temperature on plant morphology and nitrogen accumulation were examined in rice (Oryza sativa L.) during vegetative growth. The results showed that the shoot biomass of the plants was greater at 27°C (high nighttime temperature, HNT) than at 22°C (CK). However, the increase in both shoot and root biomasses was not significant under 10 mg N/L. The shoot nitrogen concentrations were 16.1% and 16.7% higher in HNT than in CK under 160 and 40 mg N/L. These results suggest that plant N uptake was enhanced under HNT; however, the positive effect might be limited by the N status of the plants. In addition, leaf area, plant height, root maximum length, root and shoot nitrogen concentrations, soluble leaf protein content, and soluble leaf carbohydrate content were greater in HNT than in CK under 40 and 160 mg N/L, while fresh root volume, root number, and the content of free amino acid in leaf were not significantly different between HNT and CK regardless of nitrogen levels. Moreover, leaf GS activity under HNT was increased at 160 mg N/L compared with that under CK, which might partly explain the positive effect of HNT on soluble protein and carbohydrate content.

Impact of calcification on Murray law-based quantitative flow ratio for physiological assessment of intermediate coronary stenoses.

BACKGROUND: To investigate the influence of coronary calcification on the diagnostic performance of Murray law-based quantitative flow ratio (µQFR) in identifying hemodynamically significant coronary lesions referenced to fractional flow reserve (FFR). METHODS: A total of 571 intermediate lesions from 534 consecutive patients (66.1 ± 10.0 years, 67.2% males) who underwent coronary angiography and simultaneous FFR measurement were included. Calcific deposits were graded by angiography as none or mild (spots), moderate (involving ≤ 50% of the reference vessel diameter), and severe (> 50%). Performance of µQFR to detect functional ischemia (FFR ≤ 0.80) was evaluated, including diagnostic parameters and areas under the receiver-operating curves (AUCs). RESULTS: The discrimination of ischemia by µQFR was comparable between none/mild and moderate/severe calcification (AUC: 0.91 [95% confidence interval: 0.88-0.93] vs. 0.87 [95% confidence interval: 0.78-0.94]; p = 0.442). No statistically significant difference was observed for µQFR between the two categories in sensitivity (0.70 vs. 0.69, p = 0.861) and specificity (0.94 vs. 0.90, p = 0.192). Moreover, µQFR showed significantly higher AUCs than quantitative coronary angiographic diameter stenosis in both vessels with none/mild (0.91 vs. 0.78, p < 0.001) and moderate/severe calcification (0.87 vs. 0.69, p < 0.001). By multivariable analysis, there was no association between calcification and µQFR-FFR discordance (adjusted odds ratio: 1.529, 95% confidence interval: 0.788-2.968, p = 0.210) after adjustment for other confounding factors. CONCLUSIONS: µQFR demonstrated robust and superior diagnostic performance for lesion-specific ischemia compared with angiography alone regardless of coronary calcification.

Sex Differences in Murray Law-Based Quantitative Flow Ratio Among Patients With Intermediate Coronary Lesions.

Background The Murray law-based quantitative flow ratio (µQFR) is a novel technique that simulates fractional flow reserve (FFR) from a single angiographic view. However, the impact of sex differences on the diagnostic performance of µQFR has not been investigated. Methods and Results In this study, FFR and µQFR were assessed in 497 intermediate stenoses (30%-70% by visual estimation) from 460 patients (34.3% female). Physiological significance was defined as FFR ≤0.80 or µQFR ≤0.80. After adjusting for potential confounders, female sex was independently associated with higher FFR (P=0.048 and 0.026, respectively) and µQFR (P=0.001 for both) in both fully adjusted and stepwise backward models. µQFR provided superior diagnostic accuracy compared with angiography alone for detecting FFR ≤0.80 in both women (area under the curve, 0.93 [95% CI, 0.88-0.97] versus 0.80 [95% CI, 0.73-0.86]; P=0.001) and men (area under the curve, 0.88 [95% CI, 0.84-0.92] versus 0.73 [95% CI, 0.68-0.78]; P<0.001), with comparable performance between the sexes (P=0.175). In the multivariable analysis, sex was not a significant factor contributing to the overall disagreement between FFR and µQFR. Conclusions Regardless of angiographic stenosis severity, women tend to have higher FFR and µQFR values than men. Furthermore, µQFR performs similarly well in both sexes and offers improved diagnostic accuracy over angiography alone, indicating its potential as a reliable, wire-free tool to identify functional ischemia.

Comparison of multilayer and single-layer coronary plaque models on stress/strain calculations based on optical coherence tomography images.

Mechanical stress and strain conditions are closely related to atherosclerotic plaque progression and rupture and have been under intensive investigations in recent years. It is well known that arteries have a three-layer structure: intima, media and adventitia. However, in vivo image-based multilayer plaque models are not available in the current literature due to lack of multilayer image segmentation data. A multilayer segmentation and repairing technique was introduced to segment coronary plaque optical coherence tomography (OCT) image to obtain its three-layer vessel structure. A total of 200 OCT slices from 20 patients (13 male; 7 female) were used to construct multilayer and single-layer 3D thin-slice models to calculate plaque stress and strain and compare model differences. Our results indicated that the average maximum plaque stress values of 20 patients from multilayer and single-layer models were 385.13 ± 110.09 kPa and 270.91 ± 95.86 kPa, respectively. The relative difference was 42.2%, with single-layer stress serving as the base value. The average mean plaque stress values from multilayer and single-layer models were 129.59 ± 32.77 kPa and 93.27 ± 18.20 kPa, respectively, with a relative difference of 38.9%. The maximum and mean plaque strain values obtained from the multilayer models were 11.6% and 19.0% higher than those from the single-layer models. Similarly, the maximum and mean cap strains showed increases of 9.6% and 12.9% over those from the single-layer models. These findings suggest that use of multilayer models could improve plaque stress and strain calculation accuracy and may have large impact on plaque progression and vulnerability investigation and potential clinical applications. Further large-scale studies are needed to validate our findings.

Quantification of patient-specific coronary material properties and their correlations with plaque morphological characteristics: An in vivo IVUS study.

BACKGROUND: A method using in vivo Cine IVUS and VH-IVUS data has been proposed to quantify material properties of coronary plaques. However, correlations between plaque morphological characteristics and mechanical properties have not been studied in vivo. METHOD: In vivo Cine IVUS and VH-IVUS data were acquired at 32 plaque cross-sections from 19 patients. Six morphological factors were extracted for each plaque. These samples were categorized into healthy vessel, fibrous plaque, lipid-rich plaque and calcified plaque for comparisons. Three-dimensional thin-slice models were constructed using VH-IVUS data to quantify in vivo plaque material properties following a finite element updating approach by matching Cine IVUS data. Effective Young's moduli were calculated to represent plaque stiffness for easy comparison. Spearman's rank correlation analysis was performed to identify correlations between plaque stiffness and morphological factor. Kruskal-Wallis test with Bonferroni correction was used to determine whether significant differences in plaque stiffness exist among four plaque groups. RESULT: Our results show that lumen circumference change has a significantly negative correlation with plaque stiffness (r = -0.7807, p = 0.0001). Plaque burden and calcification percent also had significant positive correlations with plaque stiffness (r = 0.5105, p < 0.0272 and r = 0.5312, p < 0.0193) respectively. Among the four categorized groups, calcified plaques had highest stiffness while healthy segments had the lowest. CONCLUSION: There is a close link between plaque morphological characteristics and mechanical properties in vivo. Plaque stiffness tends to be higher as coronary atherosclerosis advances, indicating the potential to assess plaque mechanical properties in vivo based on plaque compositions.

Subcellular positioning during cell division and cell plate formation in maize.

Introduction: During proliferative plant cell division, the new cell wall, called the cell plate, is first built in the middle of the cell and then expands outward to complete cytokinesis. This dynamic process requires coordinated movement and arrangement of the cytoskeleton and organelles. Methods: Here we use live-cell markers to track the dynamic reorganization of microtubules, nuclei, endoplasmic reticulum, and endomembrane compartments during division and the formation of the cell plate in maize leaf epidermal cells. Results: The microtubule plus-end localized protein END BINDING1 (EB1) highlighted increasing microtubule dynamicity during mitosis to support rapid changes in microtubule structures. The localization of the cell-plate specific syntaxin KNOLLE, several RAB-GTPases, as well as two plasma membrane localized proteins was assessed after treatment with the cytokinesis-specific callose-deposition inhibitor Endosidin7 (ES7) and the microtubule-disrupting herbicide chlorpropham (CIPC). While ES7 caused cell plate defects in Arabidopsis thaliana, it did not alter callose accumulation, or disrupt cell plate formation in maize. In contrast, CIPC treatment of maize epidermal cells occasionally produced irregular cell plates that split or fragmented, but did not otherwise disrupt the accumulation of cell-plate localized proteins. Discussion: Together, these markers provide a robust suite of tools to examine subcellular trafficking and organellar organization during mitosis and cell plate formation in maize.

Microautophagy Mediates Vacuolar Delivery of Storage Proteins in Maize Aleurone Cells.

The molecular machinery orchestrating microautophagy, whereby eukaryotic cells sequester autophagic cargo by direct invagination of the vacuolar/lysosomal membrane, is still largely unknown, especially in plants. Here, we demonstrate microautophagy of storage proteins in the maize aleurone cells of the endosperm and analyzed proteins with potential regulatory roles in this process. Within the cereal endosperm, starchy endosperm cells accumulate storage proteins (mostly prolamins) and starch whereas the peripheral aleurone cells store oils, storage proteins, and specialized metabolites. Although both cell types synthesize prolamins, they employ different pathways for their subcellular trafficking. Starchy endosperm cells accumulate prolamins in protein bodies within the endoplasmic reticulum (ER), whereas aleurone cells deliver prolamins to vacuoles via an autophagic mechanism, which we show is by direct association of ER prolamin bodies with the tonoplast followed by engulfment via microautophagy. To identify candidate proteins regulating this process, we performed RNA-seq transcriptomic comparisons of aleurone and starchy endosperm tissues during seed development and proteomic analysis on tonoplast-enriched fractions of aleurone cells. From these datasets, we identified 10 candidate proteins with potential roles in membrane modification and/or microautophagy, including phospholipase-Dα5 and a possible EUL-like lectin. We found that both proteins increased the frequency of tonoplast invaginations when overexpressed in Arabidopsis leaf protoplasts and are highly enriched at the tonoplast surface surrounding ER protein bodies in maize aleurone cells, thus supporting their potential connections to microautophagy. Collectively, this candidate list now provides useful tools to study microautophagy in plants.