The carbon costs of global wood harvests.

After agriculture, wood harvest is the human activity that has most reduced the storage of carbon in vegetation and soils1,2. Although felled wood releases carbon to the atmosphere in various steps, the fact that growing trees absorb carbon has led to different carbon-accounting approaches for wood use, producing widely varying estimates of carbon costs. Many approaches give the impression of low, zero or even negative greenhouse gas emissions from wood harvests because, in different ways, they offset carbon losses from new harvests with carbon sequestration from growth of broad forest areas3,4. Attributing this sequestration to new harvests is inappropriate because this other forest growth would occur regardless of new harvests and typically results from agricultural abandonment, recovery from previous harvests and climate change itself. Nevertheless some papers count gross emissions annually, which assigns no value to the capacity of newly harvested forests to regrow and approach the carbon stocks of unharvested forests. Here we present results of a new model that uses time discounting to estimate the present and future carbon costs of global wood harvests under different scenarios. We find that forest harvests between 2010 and 2050 will probably have annualized carbon costs of 3.5-4.2 Gt CO2e yr-1, which approach common estimates of annual emissions from land-use change due to agricultural expansion. Our study suggests an underappreciated option to address climate change by reducing these costs.

The effect of hyperlipidemia and body fat distribution on subclinical left ventricular function in obesity: a cardiovascular magnetic resonance study.

BACKGROUND: Obesity is often associated with multiple comorbidities. However, whether obese subjects with hyperlipidemia in the absence of other complications have worse cardiac indices than metabolically healthy obese subjects is unclear. Therefore, we aimed to determine the effect of hyperlipidemia on subclinical left ventricular (LV) function in obesity and to evaluate the association of cardiac parameters with body fat distribution. MATERIALS AND METHODS: Ninety-two adults were recruited and divided into 3 groups: obesity with hyperlipidemia (n = 24, 14 males), obesity without hyperlipidemia (n = 25, 13 males), and c ntrols (n = 43, 25 males). LV strain parameters (peak strain (PS), peak diastolic strain rate (PDSR), peak systolic strain rate) derived from cardiovascular magnetic resonance tissue tracking were measured and compared. Dual-energy X-ray absorptiometer was used to measure body fat distribution. Correlations of hyperlipidemia and body fat distribution with LV strain were assessed by multivariable linear regression. RESULTS: Obese individuals with preserved LV ejection fraction showed lower global LV longitudinal, circumferential, and radial PS and longitudinal and circumferential PDSR than controls (all P < 0.05). Among obese patients, those with hyperlipidemia had lower longitudinal PS and PDSR and circumferential PDSR than those without hyperlipidemia (- 12.8 ± 2.9% vs. - 14.2 ± 2.7%, 0.8 ± 0.1 s-1 vs. 0.9 ± 0.3 s-1, 1.2 ± 0.2 s-1 vs. 1.4 ± 0.2 s-1; all P < 0.05). Multivariable linear regression demonstrated that hyperlipidemia was independently associated with circumferential PDSR (ß = - 0.477, P < 0.05) in obesity after controlling for growth differences, other cardiovascular risk factors, and central fat distribution. In addition, android fat had an independently negative relationship with longitudinal and radial PS (ß = - 0.486 and ß = - 0.408, respectively; all P < 0.05); and visceral fat was negatively associated with longitudinal PDSR (ß = - 0.563, P < 0.05). Differently, gynoid fat was positively correlated with circumferential PS and PDSR and radial PDSR (ß = 0.490, ß = 0.481, and ß = 0.413, respectively; all P < 0.05). CONCLUSION: Hyperlipidemia is independently associated with subclinical LV diastolic dysfunction in obesity. Central fat distribution (android and visceral fat) has a negative association, while peripheral fat distribution (gynoid fat) has a positive association on subclinical LV function. These results suggest that appropriate management of hyperlipidemia may be beneficial for obese patients, and that the differentiation of fat distribution in different regions may facilitate the precise management of obese patients. Clinical trials registration Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476).

Radiomics based on HRCT can predict RP-ILD and mortality in anti-MDA5 + dermatomyositis patients: a multi-center retrospective study.

OBJECTIVES: To assess the effectiveness of HRCT-based radiomics in predicting rapidly progressive interstitial lung disease (RP-ILD) and mortality in anti-MDA5 positive dermatomyositis-related interstitial lung disease (anti-MDA5 + DM-ILD). METHODS: From August 2014 to March 2022, 160 patients from Institution 1 were retrospectively and consecutively enrolled and were randomly divided into the training dataset (n = 119) and internal validation dataset (n = 41), while 29 patients from Institution 2 were retrospectively and consecutively enrolled as external validation dataset. We generated four Risk-scores based on radiomics features extracted from four areas of HRCT. A nomogram was established by integrating the selected clinico-radiologic variables and the Risk-score of the most discriminative radiomics model. The RP-ILD prediction performance of the models was evaluated by using the area under the receiver operating characteristic curves, calibration curves, and decision curves. Survival analysis was conducted with Kaplan-Meier curves, Mantel-Haenszel test, and Cox regression. RESULTS: Over a median follow-up time of 31.6 months (interquartile range: 12.9-49.1 months), 24 patients lost to follow-up and 46 patients lost their lives (27.9%, 46/165). The Risk-score based on bilateral lungs performed best, attaining AUCs of 0.869 and 0.905 in the internal and external validation datasets. The nomogram outperformed clinico-radiologic model and Risk-score with AUCs of 0.882 and 0.916 in the internal and external validation datasets. Patients were classified into low- and high-risk groups with 50:50 based on nomogram. High-risk group patients demonstrated a significantly higher risk of mortality than low-risk group patients in institution 1 (HR = 4.117) and institution 2 cohorts (HR = 7.515). CONCLUSION: For anti-MDA5 + DM-ILD, the nomogram, mainly based on radiomics, can predict RP-ILD and is an independent predictor of mortality.

Effect of Metabolic Syndrome on Left Atrial and Left Ventricular Deformation and Atrioventricular Interactions in Patients With Myocardial Infarction.

BACKGROUND: Metabolic syndrome (MetS) is associated with worse prognosis in patients with myocardial infarction (MI). However, it is unclear how MetS in MI patients is associated with left atrial (LA) and left ventricular (LV) deformation. PURPOSE: To determine the effect of MetS on LA and LV deformation and atrioventricular interactions in MI patients. STUDY TYPE: Retrospective. POPULATION: One hundred eighty-one MI patients (73 MetS+ and 108 MetS-), 107 age- and sex-matched controls (49 MetS+ and 58 MetS-). FIELD STRENGTH/SEQUENCE: 3.0 T/balanced steady-state free precession (SSFP)/segmented phase-sensitive inversion recovery SSFP sequence. ASSESSMENT: LA strain and strain rates (reservoir, conduit, and active), left atrioventricular coupling index (LACI), and LV geometry and radial, circumferential and longitudinal global peak strains (PS) were compared among groups. STATISTICAL TESTS: Two-way analysis of variance, Spearman and Pearson's correlation coefficients, and multivariable linear regression analysis. P value <0.05 indicated statistical significance. RESULTS: Compared with controls, the MI patients with or without MetS showed impaired LA function (reservoir, conduit, and active) and LV deformation (radial, circumferential, and longitudinal PS) and higher LACI. The MetS+ group had lower LA reservoir and conduit function and LV deformation than MetS- group. The MetS-MI interaction was not statistically significant. Furthermore, multivariable linear regression showed that MetS was independently associated with LA and LV deformation (ß = -0.181 to -0.209) in MI patients; LA function was independently associated with LV circumferential PS (ß = 0.230 to 0.394) and longitudinal PS (ß = 0.189 to 0.420), and LA passive strain and strain rate were negatively associated with LV mass (ß = -0.178 and -0.298). DATA CONCLUSION: MetS may be associated with the LA and LV dysfunction in MI patients. Impaired LV deformation and LV hypertrophy are independently associated with LA dysfunction in MI patients, and the MI patients have higher LACI than controls, suggesting atrioventricular interaction alterations. EVIDENCE LEVEL: 4 TECHNICAL EFFICACY: 3.

Optimizing coronary CT angiography quality with motion-compensated reconstruction for second-generation dual-layer spectral detector CT.

OBJECTIVES: To investigate the effect of motion-compensated reconstruction (MCR) algorithm on improving the image quality of coronary computed tomography angiography (CCTA) using second-generation dual-layer spectral detector computed tomography (DLCT), and to evaluate the influence of heart rate (HR) on the motion-correction efficacy of this algorithm. MATERIALS AND METHODS: We retrospectively enrolled 127 patients who underwent CCTA for suspected coronary artery disease using second-generation DLCT. We divided the patients into two subgroups according to their average HR during scanning: the "HR < 75 bpm" group and the "HR ≥ 75 bpm" group. All images were reconstructed by the standard (STD) algorithm and MCR algorithm. Subjective image quality (4-point Likert scale), interpretability, and objective image quality between the STD and MCR in the whole population and within each subgroup were compared. RESULTS: MCR showed significantly higher Likert scores and interpretability than STD on the per-segment (3.58 ± 0.69 vs. 2.82 ± 0.93, 98.4% vs. 91.9%), per-vessel (3.12 ± 0.81 vs. 2.12 ± 0.74, 96.3% vs. 78.7%) and per-patient (2.57 ± 0.76 vs. 1.62 ± 0.55, 90.6% vs. 59.1%) levels (all p < 0.001). In the analysis of HR subgroups on a per-vessel basis of interpretability, significant differences were observed only in the right coronary artery in the low HR group, whereas significant differences were noted in three major coronary arteries in the high HR group. For objective image quality assessment, MCR significantly improved the SNR (13.22 ± 4.06 vs. 12.72 ± 4.06) and the contrast-to-noise ratio (15.84 ± 4.82 vs. 15.39 ± 4.38) compared to STD (both p < 0.001). CONCLUSION: MCR significantly improves the subjective image quality, interpretability, and objective image quality of CCTA, especially in patients with higher HRs. CLINICAL RELEVANCE STATEMENT: The motion-compensated reconstruction algorithm of the second-generation dual-layer spectral detector computed tomography is helpful in improving the image quality of coronary computed tomography angiography in clinical practice, especially in patients with higher heart rates. KEY POINTS: Motion artifacts from cardiac movement affect the quality and interpretability of coronary computed tomography angiography (CCTA). This motion-compensated reconstruction (MCR) algorithm significantly improves the image quality of CCTA in clinical practice. Image quality improvement by using MCR was more significant in the high heart rate group.

Myocardial tissue remodeling in early adult obesity and its association with regional adipose tissue distribution and ectopic fat deposits: a prospective study.

OBJECTIVES: To evaluate the left ventricular (LV) myocardial tissue characteristics in early adult obesity and its association with regional adipose tissue and ectopic fat deposition. METHODS: Forty-nine obese adults (mean body mass index: 29.9 ± 2.0 kg/m2) and 44 healthy controls were prospectively studied. LV native and post-contrast T1 values, extracellular volume fraction (ECV), regional adipose tissue (epicardial, visceral, and subcutaneous adipose tissue (EAT, VAT, and SAT)), and ectopic fat deposition (hepatic and pancreatic proton density fat fractions (H-PDFF and P-PDFF)) based on magnetic resonance imaging were compared. The association was assessed by multivariable linear regression. RESULTS: The obese participants showed reduced global ECV compared to the healthy controls (p < 0.05), but there was no significant difference in global native or post-contrast T1 values between the two groups. Additionally, the obese individuals exhibited higher EAT, VAT, SAT, H-PDFF, and P-PDFF than the controls (p < 0.05). ECV was associated with insulin resistance, dyslipidemia, and systolic blood pressure (SBP) (p < 0.05). Multiple linear regression demonstrated that H-PDFF and SAT were independently associated with ECV in entire population (ß = - 0.123 and - 0.012; p < 0.05). CONCLUSIONS: Reduced myocardial ECV in patients with mild-to-moderate obesity and its relationship to SBP may indicate that cardiomyocyte hypertrophy, rather than extracellular matrix expansion, is primarily responsible for myocardial tissue remodeling in early adult obesity. Our findings further imply that H-PDFF and SAT are linked with LV myocardial tissue remodeling in this cohort beyond the growth difference and cardiovascular risk factors. CLINICAL TRIALS REGISTRATION: Effect of lifestyle intervention on metabolism of obese patients based on smart phone software (ChiCTR1900026476). CLINICAL RELEVANCE STATEMENT: Myocardial fibrosis in severe obesity predicts poor prognosis. We showed that cardiomyocyte hypertrophy, not myocardial fibrosis, is the main myocardial tissue characteristic of early obesity. This finding raises the possibility that medical interventions, like weight loss, may prevent cardiac fibrosis. KEY POINTS: • Myocardial tissue characteristics in early adult obesity are unclear. • Myocardial extracellular volume fraction (ECV) can be quantitatively evaluated using T1 mapping based on cardiac magnetic resonance imaging (MRI). • Cardiac MRI-derived ECV may noninvasively evaluate myocardial tissue remodeling in early adult obesity.

Association of abdominal adiposity, hepatic shear stiffness with subclinical left-ventricular remodeling evaluated by magnetic resonance in adults free of overt cardiovascular diseases: a prospective study.

BACKGROUND: Abdominal ectopic fat deposition and excess visceral fat depots in obesity may be related to cardiovascular disease (CVD) as both are involved in the metabolic syndrome (MetS). The awareness of the link between abdominal adiposity and subclinical cardiac remodeling would help improve treatment and outcome. Besides, liver fibrosis has also shown a potential relationship with cardiac dysfunction. Thus, we aimed to investigate the associations of magnetic resonance (MR)-based abdominal adiposity and hepatic shear stiffness with subclinical left ventricular (LV) remodeling while taking account of MetS-related confounders in adults free of overt CVD. METHODS: This was an exploratory, prospective study of 88 adults (46 subjects with obesity, 42 healthy controls) who underwent 3 T cardiac and body MR exams. Measures of abdominal MR included hepatic and pancreatic proton density fat fraction (H-PDFF and P-PDFF), hepatic shear stiffness by MR elastography, and subcutaneous and visceral adipose tissue (SAT and VAT). Cardiac measures included epicardial adipose tissue (EAT) and parameters of LV geometry and function. Associations were assessed using Pearson correlation and multivariable linear regression analyses, in which age, sex, and MetS-related confounders were adjusted for. RESULTS: The LV ejection fractions of all participants were within the normal range. Higher H-PDFF, P-PDFF, SAT and VAT were independently associated with lower LV global myocardial strain parameters (radial, circumferential and longitudinal peak strain [PS], longitudinal peak systolic strain rate and diastolic strain rate) (ß = - 0.001 to - 0.41, p < 0.05), and P-PDFF, SAT and VAT were independently and positively associated with LV end-diastolic volume and stroke volume (ß = 0.09 to 3.08, p ≤ 0.02) in the over-all cohort. In the obesity subgroup, higher P-PDFF and VAT were independently associated with lower circumferential and longitudinal PS, respectively (ß = - 0.29 to - 0.05, p ≤ 0.01). No independent correlation between hepatic shear stiffness and EAT or LV remodeling was found (all p ≥ 0.05). CONCLUSIONS: Ectopic fat depositions in the liver and pancreas, and excess abdominal adipose tissue pose a risk of subclinical LV remodeling beyond MetS-related CVD risk factors in adults without overt CVD. VAT may play a more considerable role as a risk factor for subclinical LV dysfunction than does SAT in individuals with obesity. The underlying mechanisms of these associations and their longitudinal clinical implications need further investigation.

Impact of T2DM on right ventricular systolic dysfunction and interventricular interactions in patients with essential hypertension: evaluation using CMR tissue tracking.

BACKGROUND: Previous studies reported that there was right ventricular (RV) systolic dysfunction in patients with hypertension. The aim of this study was to evaluate the impact of type 2 diabetes mellitus (T2DM) on RV systolic dysfunction and interventricular interactions using cardiac magnetic resonance feature tracking (CMR-FT) in patients with essential hypertension. METHODS AND METHODS: Eighty-five hypertensive patients without T2DM [HTN(T2DM -)], 58 patients with T2DM [HTN(T2DM +)] and 49 normal controls were included in this study. The biventricular global radial, circumferential and longitudinal peak strains (GRS, GCS, GLS, respectively) and RV regional strains at the basal-, mid- and apical-cavity, were calculated with CMR-FT and compared among controls and different patient groups. Backward stepwise multivariable linear regression analyses were used to determine the effects of T2DM and left ventricular (LV) strains on RV strains. RESULTS: The biventricular GLS and RV apical longitudinal strain deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM +) groups. RV middle longitudinal strain in patient groups were significantly reduced, and LV GRS and GCS and RV basal longitudinal strain were decreased in HTN(T2DM +) but preserved in HTN(T2DM-) group. Multivariable regression analyses adjusted for covariates demonstrated that T2DM was independently associated with LV strains (LV GRS: ß = - 4.278, p = 0.004, model R2 = 0.285; GCS: ß = 1.498, p = 0.006, model R2 = 0.363; GLS: ß = 1.133, p = 0.007, model R2 = 0.372) and RV GLS (ß = 1.454, p = 0.003, model R2 = 0.142) in hypertension. When T2DM and LV GLS were included in the multiple regression analysis, both T2DM and LV GLS (ß = 0.977 and 0.362, p = 0.039 and < 0.001, model R2 = 0.224) were independently associated with RV GLS. CONCLUSIONS: T2DM exacerbates RV systolic dysfunction in patients with hypertension, which may be associated with superimposed LV dysfunction by coexisting T2DM and suggests adverse interventricular interactions.

The effect of community-acquired pneumonia on myocardial injury in systemic lupus erythematosus: Insights from cardiac magnetic resonance.

OBJECTIVES: Myocardial injury (MInj) in systemic lupus erythematosus (SLE) has been observed in several studies. However, clinical predictors of MInj remain unclear. We aim to explore the effects of community-acquired pneumonia (CAP) on MInj in SLE patients according to cardiac magnetic resonance (CMR) T1 mapping. METHODS: SLE patients with or without CAP and healthy controls underwent CMR screening. The CMR protocol included: cines, T1- and T2 mapping, and late gadolinium enhancement (LGE). Clinical characteristics, CMR findings, and T1 mapping measuremments were compared between subgroups. Clinical assessment was performed on the subjects. RESULTS: Thirty-eight SLE patients were screened, including 18 patients with CAP (CAP group) and 20 age- and gender-matched patients without CAP (non-CAP group) as well as 26 healthy controls. The platelet count of CAP group was higher than the non-CAP group (p = 0.015). Compared with the health control group, native T1 was higher in the CAP group (p < 0.001) and the non-CAP group (p = 0.002). ECV was higher in the CAP group (p < 0.001) and the non-CAP group (p = 0.002). The LV ejection fraction (p = 0.049) and RV ejection fraction (p = 0.026) of the CAP group was lower than that of the healthy control group, whereas no significant difference was observed between non-CAP and healthy control groups. CONCLUSIONS: This is the first study that assesses the effects of CAP on MInj of SLE patients by CMRI T1 mapping. We highlight SLE patients with CAP who are at increased risk of MInj, manifesting as myocardial inflammation, diffuse myocardial fibrosis, and decreased ventricular function.

Image quality and diagnostic performance evaluation in transcatheter aortic valve implantation candidates with atrial fibrillation using a whole-heart coverage CT scanner.

OBJECTIVE: To evaluate the image quality and diagnostic performance for obstructive coronary artery disease of transcatheter aortic valve implantation (TAVI) patients with atrial fibrillation (AF) during TAVI planning CT using a whole-heart coverage CT scanner. METHODS: Eighty-eight consecutive TAVI candidates with AF (50 men, 74 ± 6 years) who underwent both TAVI planning CT and invasive coronary catheter angiography (ICA) were retrospectively analyzed. With ICA results as the reference standard, the accuracy of TAVI planning CT for lesion detection on a per-vessel and per-patient level was calculated. Meanwhile, image quality, contrast volume, and effective dose (ED) were evaluated. A 5-point visual scale (1-5) was used to assess the subjective image quality. The CT value and signal-to-noise ratio were measured for the left main coronary artery (LM), left anterior descending (LAD), left circumflex (LCX), and right coronary arteries (RCA). RESULTS: The ED for CCTA was 3.25 ± 1.39 mSv and contrast volume was 58.14 ± 12.34 mL. A total of 1371 (1371/1408 = 97.4%) segments with diameter > 1.5 mm were analyzed. For the subjective evaluation, the mean score was 3.99 ± 0.96 for overall image quality. The mean CT values in LM, RCA, LCX, and LAD were all above 400 HU. For the detection of > 50% stenosis, TAVI planning CT provided on the per-vessel and per-patient basis 97.06% and 100% in sensitivity, 96.23% and 89.06% in specificity, 99.7% and 100% in negative predictive value, and 73.3% and 77.4% in positive predictive value, respectively. CONCLUSION: TAVI planning CT with whole-heart coverage demonstrates good CCTA image quality and a high sensitivity and NPV in excluding obstructive CAD in TAVI candidates with AF. KEY POINTS: • Transcatheter aortic valve implantation planning (TAVI) CT with whole-heart coverage enables good image quality of CCTA in TAVI candidates with atrial fibrillation. • Obstructive coronary artery disease may be excluded with high accuracy in transcatheter aortic valve implantation (TAVI) candidates with atrial fibrillation with the usage of whole-heart coverage TAVI planning CT.

Hydrogel composite scaffolds achieve recruitment and chondrogenesis in cartilage tissue engineering applications.

BACKGROUND: The regeneration and repair of articular cartilage remains a major challenge for clinicians and scientists due to the poor intrinsic healing of this tissue. Since cartilage injuries are often clinically irregular, tissue-engineered scaffolds that can be easily molded to fill cartilage defects of any shape that fit tightly into the host cartilage are needed. METHOD: In this study, bone marrow mesenchymal stem cell (BMSC) affinity peptide sequence PFSSTKT (PFS)-modified chondrocyte extracellular matrix (ECM) particles combined with GelMA hydrogel were constructed. RESULTS: In vitro experiments showed that the pore size and porosity of the solid-supported composite scaffolds were appropriate and that the scaffolds provided a three-dimensional microenvironment supporting cell adhesion, proliferation and chondrogenic differentiation. In vitro experiments also showed that GelMA/ECM-PFS could regulate the migration of rabbit BMSCs. Two weeks after implantation in vivo, the GelMA/ECM-PFS functional scaffold system promoted the recruitment of endogenous mesenchymal stem cells from the defect site. GelMA/ECM-PFS achieved successful hyaline cartilage repair in rabbits in vivo, while the control treatment mostly resulted in fibrous tissue repair. CONCLUSION: This combination of endogenous cell recruitment and chondrogenesis is an ideal strategy for repairing irregular cartilage defects.

Effect of Anastomosis Angles on Retrograde Perfusion and Hemodynamics of Hybrid Treatment for Thoracoabdominal Aortic Aneurysm.

BACKGROUND: Hemodynamic effects on the retrograde visceral reconstruction (RVR) for thoracoabdominal aortic aneurysms treatment by anastomotic angle remains unclear. This study aims to qualitatively and quantitatively investigate the effects of different anastomotic angles on hemodynamics and patency. METHODS: Three RVR models with 45°, 60° and 90° anastomotic angles were reconstructed respectively by manipulating apostoperative patient-specific model. The manipulated models of the RVRs were numerically simulated and analyzed in terms of hemodynamics including theinstant and cumulative patency, flow pattern and indicators based on wall shear stress (WSS). RESULTS: Although a smaller anastomotic angle may decrease the patency rate of common iliac arteries, it can improve the visceral perfusion during a cardiac cycle. More importantly, RVR with the smallest anastomotic angle experienced a minimal low time-averaged wall shear stress, high oscillatory shear index and relative residence time in the anastomosis region, whereas the largest anastomotic angle can introduce more unfavorable WSS in the graft trunk. Furthermore, a spiral flow pattern was observed in the proximal graft trunk of all three models, where no high-risk shear distribution was detected in this region. CONCLUSION: A smaller anastomotic angle may have more benefits of hemodynamic environment in RVR, especially the WSS distribution and flow pattern in the graft trunk. We may also suggest that additional stents or an extended cuff for the graft can be used to induce spiral flow intentionally, which can further improve local hemodynamic environment and long-term prognosis.

Modern microextraction techniques for natural products.

Natural product analysis has gained wide attention in recent years, especially for herbal medicines, which contain complex ingredients and play a significant clinical role in the therapy of numerous diseases. The constituents of natural products are usually found at low concentrations, and the matrices are complex. Thus, the extraction of target compounds from natural products before analysis by analytical instruments is very significant for human health and its wide application. The commonly used traditional extraction methods are time-consuming, using large amounts of sample and organic solvents, as well as expensive and inefficient. Recently, microextraction techniques have been used for natural product extraction to overcome the disadvantages of conventional extraction methods. In this paper, the successful applications of and recent developments in microextraction techniques including solvent-based and sorbent-based microextraction methods, in natural product analysis in recent years, especially in the last 5 years, are reviewed for the first time. Their features, advantages, disadvantages, and future development trends are also discussed.

Impact of gender on left ventricular deformation in patients with essential hypertension assessed by cardiac magnetic resonance tissue tracking.

Left ventricular (LV) myocardial strain impairment has been demonstrated in hypertension despite normal LV ejection fraction (LVEF); however, limited data exist on any difference in results between genders. The aim of this study was to investigate the impact of gender on LV deformation in patients with essential hypertension. This was a cross-sectional study, in which 94 patients (47 men and 47 women) with essential hypertension and 62 age- and gender-matched controls (31 men and 31 women) were enrolled. A 3.0 T/two-dimensional balanced steady-state free precession cine, late gadolinium enhancement was used. The LV endocardial and epicardial contours were drawn by radiologists, then LV volumes, mass, function, and myocardial strain, including peak global radial (GRS), circumferential (GCS), and longitudinal strain (GLS) were automatically calculated. Chi-square test, Student's t-test, general linear model analysis, univariate linear regression analysis, stepwise multivariate linear regression analysis, and intraclass correlation coefficient analysis were performed. Women had significantly higher magnitudes of LV GRS, GCS, and GLS than men in both patients and controls (all p < 0.05). In the overall patients, LV GLS was significantly reduced compared with controls (p < 0.05), while GRS and GCS were preserved (p = 0.092 and 0.27, respectively). Compared with their counterpart controls, LV GRS, GCS, and GLS (all p < 0.05) were significantly reduced in hypertensive men, while only GLS (p < 0.05) was reduced in hypertensive women. Male gender and its interaction with hypertension were associated with higher LV mass and volume, decreased LV GRS, GCS, and GLS compared with hypertensive women. Multivariate analyses revealed that gender and LVEF were independently associated with GRS, GCS, and GLS (all p < 0.001) in hypertension. LV deformation is significantly reduced in hypertension, and gender may influence the response of LV deformation to hypertension, with men suffering more pronounced subclinical myocardial dysfunction. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 3.

[Extranodal Rosai-Dorfman Disease of Anterior Mediastinum: A Case Report].

A 28-year-old female patient was referred to and admitted in our hospital for presence of anterior mediastinal mass for 4 years. Enchanced chest computed tomography (CT) revealed an anterior mediastinal mass of soft-tissue density measuring 7.1 cm×3.8 cm with slight homogeneous enhancement after intravenous administration of contrast agent. The mass was clinically considered a thymoma. Then, surgical excision of anterior mediastinal mass was performed under general anesthesia. Postoperative histopathology revealed that there were foamy histiocyte clusters on the background of fibrous tissue hyperplasia and hyaline, with lymphoid hyperplasia, infiltration of plasma cells, and the presence of emperipolesis of lymphocytes and plasma cells in the tissue cells. Immunohistochemistry showed S100 protein (+), cluster of differentiation (CD) 68 (+), CD163 (+), immunoglobulin G4 (+), and CD1a (-). Eventually, confirmed diagnosis of extranodal Rosai-Dorfman disease was made. The patient showed no clinical symptoms and no recurrence was found on CT images over the 3-year followup. In clinical practice, this disease should be differentiated from other anterior mediastinal masses such as thymoma, lymphoma, and teratoma.

The additive effects of type 2 diabetes mellitus on left ventricular deformation and myocardial perfusion in essential hypertension: a 3.0 T cardiac magnetic resonance study.

BACKGROUND: Type 2 diabetes mellitus (T2DM) increases the risks of heart failure and mortality in patients with hypertension, however the underlying mechanism is unclear. This study aims to investigate the impact of coexisting T2DM on left ventricular (LV) deformation and myocardial perfusion in hypertensive individuals. MATERIALS AND METHODS: Seventy hypertensive patients without T2DM [HTN(T2DM-)], forty patients with T2DM [HTN(T2DM+)] and 37 age- and sex-matched controls underwent cardiac magnetic resonance examination. Left ventricular (LV) myocardial strains, including global radial (GRPS), circumferential (GCPS) and longitudinal peak strain (GLPS), and resting myocardial perfusion indices, including upslope, time to maximum signal intensity (TTM), and max signal intensity (MaxSI), were measured and compared among groups by analysis of covariance after adjusting for age, sex, body mass index (BMI) and heart rate followed by Bonferroni's post hoc test. Backwards stepwise multivariable linear regression analyses were performed to determine the effects of T2DM on LV strains and myocardial perfusion indices in patients with hypertension. RESULTS: Both GRPS and GLPS deteriorated significantly from controls, through HTN(T2DM-), to HTN(T2DM+) group; GCPS in HTN(T2DM+) group was lower than those in both HTN(T2DM-) and control groups. Compared with controls, HTN(T2DM-) group showed higher myocardial perfusion, and HTN(T2DM+) group exhibited lower perfusion than HTN(T2DM-) group and controls. Multiple regression analyses considering covariates of systolic blood pressure, age, sex, BMI, heart rate, smoking, indexed LV mass and eGFR demonstrated that T2DM was independently associated with LV strains (GRPS: p = 0.002, model R2= 0.383; GCPS: p < 0.001, model R2= 0.472; and GLPS: p = 0.002, model R2= 0.424, respectively) and perfusion indices (upslope: p < 0.001, model R2= 0.293; TTM: p < 0.001, model R2= 0.299; and MaxSI: p < 0.001, model R2= 0.268, respectively) in hypertension. When both T2DM and perfusion indices were included in the regression analyses, both T2DM and TTM were independently associated with GRPS (p = 0.044 and 0.017, model R2= 0.390) and GCPS (p = 0.002 and 0.001, model R2= 0.424), and T2DM but not perfusion indices was independently associated with GLPS (p = 0.002, model R2= 0.424). CONCLUSION: In patients with hypertension, T2DM had an additive deleterious effect on subclinical LV systolic dysfunction and myocardial perfusion, and impaired myocardial perfusion by coexisting T2DM was associated with deteriorated LV systolic dysfunction.

Influence of Hemodialysis Catheter Insertion on Hemodynamics in the Central Veins.

Central venous catheter (CVC) related thrombosis is a major cause of CVC dysfunction in patients under hemodialysis. The aim of our study was to investigate the impact of CVC insertion on hemodynamics in the central veins and to examine the changes in hemodynamic environments that may be related to thrombus formation due to the implantation of CVC. Patient-specific models of the central veins with and without CVC were reconstructed based on computed tomography images. Flow patterns in the veins were numerically simulated to obtain hemodynamic parameters such as time-averaged wall shear stress (TAWSS), oscillating shear index (OSI), relative residence time (RRT), and normalized transverse wall shear stress (transWSS) under pulsatile flow. The non-Newtonian effects of blood flow were also analyzed using the Casson model. The insertion of CVC caused significant changes in the hemodynamic environment in the central veins. A greater disturbance and increase of velocity were observed in the central veins after the insertion of CVC. As a result, TAWSS and transWSS were markedly increased, but most parts of OSI and RRT decreased. Newtonian assumption of blood flow would overestimate the increase in TAWSS after CVC insertion. High wall shear stress (WSS) and flow disturbance, especially the multidirectionality of the flow, induced by the CVC may be a key factor in initiating thrombosis after CVC insertion. Accordingly, approaches to decrease the flow disturbance during CVC insertion may help restrain the occurrence of thrombosis. More case studies with pre-operative and postoperative modeling and clinical follow-up need to be performed to verify these findings. Non-Newtonian blood flow assumption is recommended in computational fluid dynamics (CFD) simulations of veins with CVCs.

Determinants of the ratio of actual to potential evapotranspiration.

A widely used approach for estimating actual evapotranspiration (AET) in hydrological and earth system models is to constrain potential evapotranspiration (PET) with a single empirical stress factor (Ω = AET/PET). Ω represents the water availability and is fundamentally linked to canopy-atmosphere coupling. However, the mean and seasonal variability of Ω in the models have rarely been evaluated against observations, and the model performances for different climates and biomes remain unclear. In this study, we first derived the observed Ω from 28 FLUXNET sites over North America during 2000-2007, which was then used to evaluate Ω in six large-scale model-based datasets. Our results confirm the importance of incorporating canopy height in the formulation of aerodynamic conductance in the case of forests. Furthermore, leaf area index (LAI) is central to the prediction of Ω and can be quantitatively linked to the partitioning between transpiration and soil evaporation (R2  = 0.43). The substantial differences between observed and model-based Ω in forests (range: 0.2~0.9) are highly related to the way these models estimated PET and the way they represented the responses of Ω to the environmental drivers, especially wind speed and LAI. This is the first assessment of Ω in models based on in situ observations. Our findings demonstrate that the observed Ω is useful for evaluating, validating, and optimizing the modeling of AET and thus of water and energy balances.

Ecofriendly microwave-assisted reaction and extraction of bioactive compounds from hawthorn leaf.

INTRODUCTION: The main active components in hawthorn leaves possess various biological activities such as anti-inflammatory, antioxidant, and hypolipidemic effects. Therefore, it is necessary to develop an effective and reliable extraction method to extract these active compounds from hawthorn leaves. OBJECTIVE: To establish a simple, rapid, and sensitive method for extraction and determination of polyphenolic compounds from hawthorn leaves. METHODS: In this study, a microwave-assisted reaction and extraction (MARE) combined with ultra-high-performance liquid chromatography with ultraviolet detector method was established to extract and determine the polyphenolic compounds in hawthorn leaves. The solid reagent aqueous solutions were applied as extraction solvents, preventing the use of organic solvents. The target analytes were identified by quadrupole time-of-flight tandem mass spectrometry. Several experimental parameters that can significantly affect the extraction efficiency were evaluated and optimised. RESULTS: The optimal conditions were as follows: 0.1 g of sodium carbonate was used as solid reagent, the amount of sodium borate was set at 0.01 g, extraction time was 10 min, extraction temperature was set at 50°C, pH value was adjusted to 7. The validation experiments demonstrated that the method had high sensitivity with the limits of detection in the range 26.5-37.7 ng/mL. The average recoveries ranged from 80.22% to 93.27%. CONCLUSION: In this work, the proposed MARE method was successfully applied to extract and determine polyphenolic compounds in hawthorn leaf samples. Compared with other reported methods, the present method was faster, greener, and more sensitive.

[Risk Factors for Adverse Aortic Remodeling in Post-TEVAR Patients with Acute Stanford B Aortic Dissection].

OBJECTIVES: To assess morphological changes of distal aorta and the risk factors for adverse aortic remodeling inpost-TEVAR（thoracic endovascular aortic repair） patients with acute Stanford B aortic dissection. METHODS: We retrospectively investigated the patients who underwent TEVAR for a type B dissection between October 2005 and December 2015. CT angiogram (CTA) was obtained for each patients preoperatively, postoperatively and during the post-operational follow-up. Based on Criadol partition principle, we divided the aorta into descending thoracic aorta area, suprarenal abdominal aorta area, infrarenal abdominal aorta area and iliac artery area, and evaluated the distribution of aortic tears and the form of true and false lumen in different aortic partition. Univariate and multivariate logistic regression analyses were used to analyze the risk factors affecting distal aortic remodeling. RESULTS: Of 216 patients (mean follow-up (3.9±2.1) years) who were regularly followed up in our center, 47 patients (21.8%) occurred adverse remodeling in distal aorta. Univariate logistic regression indicated that abnormal aortic wall structure (Marfan's syndrome) and patent false lumen (existence of distal tears, decreased complete false lumen thrombosis) were associated with distal aortic adverse remodeling. Multivariate logistic regression showed that more tears in descending thoracic aorta area ( OR=1.36, 95% CI=1.12-1.58, P=0.005) and less tears in infrarenal abdominal aorta area ( OR=0.49, 95% CI=0.22-0.71, P<0.001) were independent risk factors affecting remodeling in distal aorta after TEVAR. CONCLUSIONS: Aortic wall structure abnormalities, a patent false lumen, more tears in descending thoracic aorta area, less tears in infrarenal abdominal aorta area are independent risk factors for adverse aortic remodeling in post-TEVAR patients with acute Stanford B aortic dissection.