Vein wall thickness and severity of pulmonary involvement due to sars n-cov2 virus infection.

BACKGROUND: An observational study involving patients recovered from COVID-19 was conducted in order to evaluate the presence/absence of vein wall thickness increasing, according to the severity of pulmonary involvement quantified with a CT-scoring system. METHODS: The venous wall thickness (VWT) of 31 patients (23 males and 8 females) with COVID 19 previously admitted to Federico II University Hospital of Naples was evaluated through ultrasound measurement of the common femoral Vein 1 cm proximal to the saphenous-femoral junction and the popliteal Vein 1 cm distal to the confluence of gemellary veins. Measurements were taken with an automated tool to avoid human error. All patients were evaluated in the supine position. Patients were then stratified into two groups, VWT > 1 mm and VWT < 1 mm. Lung damage was assessed through thoracic High Resolution Computer Tomography and subsequently quantified using the scoring system set out by Chung et al. CEAP-C class was calculated for all patients. RESULTS: The mean value of COVID score in VWT > 1 mm group was 7.4 (S.D. 4.83), whilst the mean value of the COVID score in the VWT < 1 mm group was 3.82 (S.D 3.34). These findings were determined to be statistically significant in a two-tie Student-T test. The linear regression test between VWT and Covid score values demonstrated a direct relationship between the two variables. CONCLUSION: These results demonstrate a link between two different aspects of the pathological effects on the vessels during a SARS-COV 2 infection. As such a common primum movens can be hypothesized in both micro-thrombotic and inflammatory processes relating to COVID 19.

Predictive role of ureteral wall thickness and patient characteristics in endoscopic treatment outcomes for ureteral stricture disease following stone surgery.

PURPOSE: To evaluate the role of certain radiological parameters and patient characteristics in predicting the success of endoscopic treatment in ureteral stricture disease. METHODS: Fifty one adult patients with ureteral stricture disease (< 1 cm) after developing due to upper ureteral stones with ureteroscopic laser disintegration were included and in addition to stone and patient parameters, radiological parameters including ureteral wall thickness (UWT) at the impacted stone site were also measured on computed tomography (CT) images. Patients were divided into two groups: Group 1: Patients with endoscopic treatment success and Group 2: Patients with endoscopic treatment failure. The possible relationship between the UWT values and other radiological parameter was comparatively evaluated. RESULTS: Mean UWT value assessed at the treated stone site was significantly higher in cases unresponsive to endoscopic treatment with values of 2.77 ± 1.03 mm and 4.25 ± 1.32 mm in Group 1 and 2 respectively. A cut off value 3.55 mm for UWT was found to be highly predictive for endoscopic treatment failure. CONCLUSIONS: Our current results indicated that assessment of UWT value at the obstructing stone could be helpful enough to predict the likelihood of failure following endoscopic management of strictures with high sensitivity and specificity. Evaluation of this particular parameter could let the endourologists to look for more rational treatment alternatives with necessary measures taken on time.

Ureteral wall thickness as a predictor for non-invasive treatment success for steinstrasse. Can we save time?

PURPOSE: We aimed to define factors affecting the non-invasive overall treatment success (medical expulsive therapy (MET) ± shock wave lithotripsy (SWL)) for uncomplicated ureteral steinstrasse (SS) clearance. METHODS: We retrospectively evaluated consecutive patients who underwent SWL for renal stones between 2017 and 2021. Patients with uncomplicated SS were included. All patient's demographic and radiological data, e.g., age, gender, pre-SWL stenting, SS site, type, leading stone size in widest diameter (< 10 mm and ≥ 10 mm), ureteral wall thickness (UWT) in mm against the leading stone were collected. If SS was diagnosed, medical treatment was given for 4 weeks. In case of MET failure, either SWL for the leading stones + MET or direct URS was done. Non-invasive treatment success (SFR) was considered if complete clearance of SS occurred with no complications or the need for invasive intervention. RESULTS: A total of 145 patients were included with mean age of 45.9 ± 12.4 years. SFR in case of MET only occurred in 27.9%. Complications happened in 26 patients (17.9%). Non-invasive treatment SFR was achieved in 78 patients (53.8%) totally where SS type I, leading stone size ≤ 10 mm type and decreased UWT around the leading stone increased treatment success. CONCLUSION: Ureteral wall thickness is an important factor predicting SS management success. Besides the decreased UWT, non-invasive management should be offered for type I SS with leading stone ≤ 10 mm.

Personalized pulmonary vein isolation with very high-power short-duration lesions guided by left atrial wall thickness: the QDOT-by-LAWT randomized trial.

AIMS: Pulmonary vein isolation (PVI) for paroxysmal atrial fibrillation (PAF) using very high-power short-duration (vHPSD) radiofrequency (RF) ablation proved to be safe and effective. However, vHPSD applications result in shallower lesions that might not be always transmural. Multidetector computed tomography-derived left atrial wall thickness (LAWT) maps could enable a thickness-guided switching from vHPSD to the standard-power ablation mode. The aim of this randomized trial was to compare the safety, the efficacy, and the efficiency of a LAWT-guided vHPSD PVI approach with those of the CLOSE protocol for PAF ablation (NCT04298177). METHODS AND RESULTS: Consecutive patients referred for first-time PAF ablation were randomized on a 1:1 basis. In the QDOT-by-LAWT arm, for LAWT ≤2.5 mm, vHPSD ablation was performed; for points with LAWT > 2.5 mm, standard-power RF ablation titrating ablation index (AI) according to the local LAWT was performed. In the CLOSE arm, LAWT information was not available to the operator; ablation was performed according to the CLOSE study settings: AI ≥400 at the posterior wall and ≥550 at the anterior wall. A total of 162 patients were included. In the QDOT-by-LAWT group, a significant reduction in procedure time (40 vs. 70 min; P < 0.001) and RF time (6.6 vs. 25.7 min; P < 0.001) was observed. No difference was observed between the groups regarding complication rate (P = 0.99) and first-pass isolation (P = 0.99). At 12-month follow-up, no significant differences occurred in atrial arrhythmia-free survival between groups (P = 0.88). CONCLUSION: LAWT-guided PVI combining vHPSD and standard-power ablation is not inferior to the CLOSE protocol in terms of 1-year atrial arrhythmia-free survival and demonstrated a reduction in procedural and RF times.

Chinese visceral adiposity index and its relation to abnormal left ventricular remodeling assessed by relative wall thickness and left ventricular mass index.

BACKGROUND AND AIMS: The Chinese visceral adipose index (CVAI) is more significantly associated with cardiometabolic risk factors than other obesity indices. This study investigated the relationship between CVAI and left ventricular (LV) remodeling. METHODS AND RESULTS: This study included 75,132 Koreans who underwent echocardiography during a health checkup. They were grouped according to quartile levels of the CVAI, body mass index (BMI), waist circumference (WC), and visceral adiposity index (VAI). LV remodeling was defined as the presence of abnormal relative wall thickness (ARWT) and left ventricular hypertrophy (LVH). Multivariate adjusted logistic regression analysis (adjusted OR [95% confidence interval]) was used to analyze the association between ARWT and LVH according to the quartile levels of each index. Receiver operating characteristic (ROC) graphs and areas under the curve (AUC) were calculated to identify the predictive ability of the indices for ARWT and LVH. ARWT was associated proportionally with CVAI quartiles in both men (second quartile: 1.42 [1.29-1.56], third quartile: 1.61 [1.46-1.77], fourth quartile: 2.01 [1.84-2.21]), and women (second quartile: 1.06 [0.78-1.45], third quartile: 1.15 [0.86-1.55], and fourth quartile: 2.09 [1.56-2.80]). LVH was significantly associated with third (1.74 [1.07-2.83]) and fourth quartile (1.94 [1.18-3.20]) groups of CVAI in women. ROC and AUC analyses indicated that CVAI was superior to other indices in predicting ARWT in men and LVH and ARWT in women. CONCLUSION: The CVAI is an effective surrogate marker of LV remodeling, particularly in women.

The athlete's heart: allometric considerations on published papers and relation to cardiovascular variables.

To evaluate the morphology of the "athlete's heart", left ventricular (LV) wall thickness (WT) and end-diastolic internal diameter (LVIDd) at rest were addressed in publications on skiers, rowers, swimmers, cyclists, runners, weightlifters (n = 927), and untrained controls (n = 173) and related to the acute and maximal cardiovascular response to their respective disciplines. Dimensions of the heart at rest and functional variables established during the various sport disciplines were scaled to body weight for comparison among athletes independent of body mass. The two measures of LV were related (r = 0.8; P = 0.04) across athletic disciplines. With allometric scaling to body weight, LVIDd was similar between weightlifters and controls but 7%-15% larger in the other athletic groups, while WT was 9%-24% enlarged in all athletes. The LVIDd was related to stroke volume, oxygen pulse, maximal oxygen uptake, cardiac output, and blood volume (r = ~ 0.9, P < 0.05), while there was no relationship between WT and these variables (P > 0.05). In conclusion, while cardiac enlargement is, in part, essential for the generation of the cardiac output and thus stroke volume needed for competitive endurance exercise, an enlarged WT seems important for the development of the wall tension required for establishing normal arterial pressure in the enlarged LVIDd.

Ultra-high-frequency ultrasound (48-70 MHz) is a promising tool for improved gastrointestinal diagnostics in infants.

AIM: To investigate the clinical feasibility of ultra-high-frequency abdominal ultrasound (UHFUS) scans of preterm and term infants. METHODS: Prospectively, 19 healthy term newborn infants were examined with conventional ultrasound (CUS) (Toshiba, Aplio i700, linear probe 14L5) and UHFUS (Visualsonics VevoMD, linear probes UHF48 and UHF70) according to a standardised protocol. Measurements of wall thickness were performed for; stomach, small intestine, colon and peritoneum. Five preterm infants, with or without suspected necrotising enterocolitis (NEC), were also examined with UHF48. Of these, only one was later diagnosed with NEC. RESULTS: Differences between CUS and UHFUS (UHF48) were found in measurements of thickness; for peritoneum 0.25 versus 0.13 mm (p < 0.001), small intestine 0.76 versus 0.64 mm (p = 0.039) and colon 0.7 versus 0.47 mm (p < 0.001) in healthy term infants. Gaining frequency from 46 to 71 MHz showed a mean reduction in measurements of peritoneum from 0.13 to 0.09 mm (p < 0.001). One preterm infant with NEC showed a fivefold and twofold increase in peritoneal and gastrointestinal wall thickness respectively, compared to healthy preterm infants. CONCLUSION: UHFUS was a clinically feasible, promising method with potential to improve gastrointestinal diagnostics in infants. Lower peritoneum thickness and gastrointestinal wall thickness were demonstrated with UHFUS compared to CUS, suggesting an overestimation by CUS.

Single measurement of bowel wall thickness using intestinal ultrasonography in children with ulcerative colitis.

BACKGROUND: Endoscopic monitoring of disease activity in patients with ulcerative colitis (UC) is important. However, frequent colonoscopic examinations are difficult to perform because of their invasiveness, especially in children. Bowel wall thickness (BWT) measurement using intestinal ultrasonography and fecal calprotectin (FC) measurement are useful noninvasive evaluation methods. METHODS: We retrospectively analyzed BWT and FC levels and evaluated the Mayo endoscopic subscore (MES) using colonoscopy in pediatric patients with UC during the same period. The BWT was evaluated using the maximum BWT (mBWT), which was the maximum value of each colonic BWT; the sum of BWT (sBWT), which was the sum of each colonic BWT; and the sum of the adjusted BWT (saBWT), which was corrected using sBWT. RESULTS: In 54 procedures from 40 patients, FC, mBWT, sBWT, and saBWT were significantly different between MES 0-1 and MES 2. The agreement between BWT and MES 2 was 193 out of 216 segments (89.4%). Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of FC were 68.8%, 84.2%, 64.7%, 86.5%, and 79.6% respectively, while those of saBWT were 81.2%, 89.5%, 76.5%, 91.9%, 87.0%, respectively. CONCLUSIONS: BWT in each colonic segment, particularly saBWT, was more useful than FC for detecting moderate colonic inflammation (MES 2) in pediatric patients with UC. Therefore, intestinal ultrasonography may be helpful in the less invasive management of pediatric patients with UC.

Unveiling the Inner Structure of Micrometric Hollow Polymeric Fibers Using Synchrotron X-Ray Nanotomography.

In this study, a novel application of synchrotron X-ray nanotomography based on high-resolution full-field transmission X-ray microscopy for characterizing the structure and morphology of micrometric hollow polymeric fibers is presented. By employing postimage analysis using an open-source software such as Tomviz and ImageJ, various key parameters in fiber morphology, including diameter, wall thickness, wall thickness distribution, pore size, porosity, and surface roughness, were assessed. Electrospun polycaprolactone fibers with micrometric diameters and submicrometric features with induced porosity via gas dissolution foaming were used to this aim. The acquired synchrotron X-ray nanotomography data were analyzed using two approaches: 3D tomographic reconstruction and 2D radiographic projection-based analysis. The results of the combination of both approaches demonstrate unique capabilities of this technique, not achievable by other available techniques, allowing for a full characterization of the internal and external morphology and structure of the fibers as well as to obtain valuable qualitative insights into the overall fiber structure.

Differential associations between abnormal cardiac left ventricular geometry types and cerebral white matter disease.

OBJECTIVES: Reduced cardiac outflow due to left ventricular hypertrophy has been suggested as a potential risk factor for development of cerebral white matter disease. Our study aimed to examine the correlation between left ventricular geometry and white matter disease volume to establish a clearer understanding of their relationship, as it is currently not well-established. METHODS: Consecutive patients from 2016 to 2021 who were ≥18 years and underwent echocardiography, cardiac MRI, and brain MRI within one year were included. Four categories of left ventricular geometry were defined based on left ventricular mass index and relative wall thickness on echocardiography. White matter disease volume was quantified using an automated algorithm applied to axial T2 FLAIR images and compared across left ventricular geometry categories. RESULTS: We identified 112 patients of which 34.8 % had normal left ventricular geometry, 20.5 % had eccentric hypertrophy, 21.4 % had concentric remodeling, and 23.2 % had concentric hypertrophy. White matter disease volume was highest in patients with concentric hypertrophy and concentric remodeling, compared to eccentric hypertrophy and normal morphology with a trend-P value of 0.028. Patients with higher relative wall thickness had higher white matter disease volume (10.73 ± 10.29 cc vs 5.89 ± 6.46 cc, P = 0.003), compared to those with normal relative wall thickness. CONCLUSION: Our results showed that abnormal left ventricular geometry is associated with higher white matter disease burden, particularly among those with abnormal relative wall thickness. Future studies are needed to explore causative relationships and potential therapeutic options that may mediate the adverse left ventricular remodeling and its effect in slowing white matter disease progression.

A Novel Method for the Measurement of the Vaginal Wall Thickness by Transvaginal Ultrasound: A Study of Inter- and Intra-Observer Reliability.

Background and Objectives: A consensus regarding the optimal sonographic technique for measuring vaginal wall thickness (VWT) is still absent in the literature. This study aims to validate a new method for measuring VWT using a biplanar transvaginal ultrasound probe and assess both its intra-operator and inter-operator reproducibility. Material and Methods: This prospective study included patients with genitourinary syndrome of menopause-related symptoms. Women were scanned using a BK Medical Flex Focus 400 with the 65 × 5.5 mm linear longitudinal transducer of an endovaginal biplanar probe (BK Medical probe 8848, BK Ultrasound, Peabody, MA, USA). Vaginal wall thickness (VWT) measurements were acquired from the anterior and posterior vaginal wall at three levels. Results: An inter-observer analysis revealed good consistency between operators at every anatomical site, and the intra-class coefficient ranged from 0.931 to 0.987, indicating high reliability. An intra-observer analysis demonstrated robust consistency in vaginal wall thickness measurements, with an intra-class coefficient exceeding 0.9 for all anatomical sites. Conclusions: The measurement of vaginal wall thickness performed by transvaginal biplanar ultrasound was easy and demonstrated good intra- and inter-operator reliability.

Genotype-dependent changes of cell wall composition influence physiological traits of a long and a non-long shelf-life tomato genotypes under distinct water regimes.

Water shortage strongly affects plants' physiological performance. Since tomato (Solanum lycopersicum) non-long shelf-life (nLSL) and long shelf-life (LSL) genotypes differently face water deprivation, we subjected a nLSL and a LSL genotype to four treatments: control (well watering), short-term water deficit stress at 40% field capacity (FC) (ST 40% FC), short-term water deficit stress at 30% FC (ST 30% FC), and short-term water deficit stress at 30% FC followed by recovery (ST 30% FC-Rec). Treatments promoted genotype-dependent elastic adjustments accompanied by distinct photosynthetic responses. While the nLSL genotype largely modified mesophyll conductance (gm ) across treatments, it was kept within a narrow range in the LSL genotype. However, similar gm values were achieved under ST 30% FC conditions. Particularly, modifications in the relative abundance of cell wall components and in sub-cellular anatomic parameters such as the chloroplast surface area exposed to intercellular air space per leaf area (Sc /S) and the cell wall thickness (Tcw ) regulated gm in the LSL genotype. Instead, only changes in foliar structure at the supra-cellular level influenced gm in the nLSL genotype. Even though further experiments testing a larger range of genotypes and treatments would be valuable to support our conclusions, we show that even genotypes of the same species can present different elastic, anatomical, and cell wall composition-mediated mechanisms to regulate gm when subjected to distinct water regimes.

Intima-media thickness of common femoral vein is increased in Behçet's disease.

The histopathological data about vascular inflammation in Behçet's disease(BD) mainly comprises patients with arterial involvement. Inflammatory cell infiltration was mainly observed around the vasa vasorum and adventitial layer of the aneurysmatic vessels, and only a few cells were seen in the intimal layer during active arteritis. There is limited data for the histopathology of venous inflammation. We recently showed that increased common femoral vein(CFV) wall thickness is a specific sign of vein wall inflammation in BD. We aimed to investigate the different vein subsections measuring the whole wall and the intima-media thickness(IMT) of CFV with ultrasonography in BD. We found increased IMT of CFV compared to controls as well as CFV wall thickness. This study shows that there is a full layer venous wall inflammation in BD independent of vascular involvement. Our results suggest that venous endothelial inflammation may trigger the thickening of the vein wall and cause thrombotic tendency in BD.

Pulmonary arterial wall thickness increased in Behçet's disease patients with major organ involvement: Is it a sign of severity?

OBJECTIVES: Behçet's disease (BD) is a unique systemic vasculitis mainly involving veins, in contrast to other vasculitides. Prior studies have shown that pulmonary arteries (PAs) have a similar structure to systemic veins. In this study we aimed to assess PA wall thickness by transthoracic echocardiography (TTE) in BD patients compared with healthy controls (HCs) and patients with non-inflammatory pulmonary embolism (NIPE). METHODS: Patients with BD (n = 77) and NIPE (n = 33) and HCs (n = 57) were studied. PA wall thickness was measured from the mid-portion of the main PA with TTE by two cardiologists blinded to cases. RESULTS: PA wall thickness was significantly lower in HCs [3.6 mm (s.d. 0.3)] compared with NIPE [4.4 mm (s.d. 0.5)] and BD [4.4 mm (s.d. 0.6)] (P < 0.001 for both). PA wall thickness was similar between BD and NIPE (P = 0.6). Among patients with BD, PA wall thickness was significantly higher in patients with major organ involvement compared with mucocutaneous limited disease [4.7 mm (s.d. 0.4) vs 3.7 (0.4), P < 0.001], HCs and NIPE (P < 0.001 and P = 0.006, respectively). PA wall thickness was comparable between patients with vascular and non-vascular major organ involvement [4.6 mm (s.d. 0.5) vs 4.7 (0.3), P = 0.3]. CONCLUSION: We observed that PA wall thickness was significantly higher in BD with major organ involvement compared with patients with only mucocutaneous limited disease, HCs and NIPE. These results suggest that increased PA wall thickness may be a sign of severe disease with major organ involvement in BD.

A new tool supporting the diagnosis of childhood-onset Behçet's disease: venous wall thickness.

OBJECTIVES: The lower extremity venous wall thickness (VWT) of Behçet's disease (BD) patients was reported to be significantly increased in adults, suggesting its use for the support of BD diagnosis. This prospective study aimed to investigate the lower extremity VWT in childhood-onset definite and incomplete BD patients and compare it to healthy age-matched controls. METHODS: Paediatric patients classified with BD according to the 2015 international paediatric BD criteria in our centre were included in the study. Intima-media thickness of the lower extremity veins to evaluate VWT was measured by ultrasonography, including common femoral vein (CFV), femoral vein (FV), vena saphena magna, vena saphena parva and popliteal vein (PV). RESULTS: In this cross-sectional study, VWT was measured in 35 patients (63% male) and 27 healthy controls (55% male). Thirteen (37%) of 35 patients met the criteria for the diagnosis of BD. The remaining 22 (63%) had incomplete BD and met two criteria. The median VWT values of both definite and incomplete BD patients were significantly higher than the control group in all veins on both sides. Regarding the best cut-off values of VWT for all lower extremity veins, the sensitivity rates were between 63% and 86%, while specificity rates were between 71% and 100%. CONCLUSION: Increased VWT was present not only in BD patients with vascular involvement but also in those without. We suggest that VWT may be a new criterion in supporting the diagnosis of childhood BD both in definite and incomplete BD patients.

Tailored ablation index based on left atrial wall thickness assessed by computed tomography for pulmonary vein isolation in patients with atrial fibrillation.

INTRODUCTION: Although left atrial wall thickness (LAWT) is known to be varied, a fixed target Ablation Index (AI) based pulmonary vein isolation (PVI) has been suggested in catheter ablation for atrial fibrillation (AF). We aimed to evaluate the efficacy and safety of PVI applying tailored AI based on LAWT assessed by cardiac computed tomography (CT). METHODS: The thick segment was defined as the segment including ≥LAWT grade 3 (≥1.5 mm). The fixed AI strategy was defined as AI targets were 450 on the anterior/roof segments and 350 on the posterior/inferior/carina segments regardless of LAWT. The tailored AI strategy consisted of AI increasing the targets to 500 on the anterior/roof segments and to 400 on the posterior/inferior/carina segments when ablating the thick segment. After PVI, acute pulmonary vein (PV) reconnection, defined by the composite of residual potential and early reconnection, was evaluated. RESULTS: A total of 156 patients (paroxysmal AF 72%) were consecutively included (86 for the fixed AI group and 70 for the tailored AI group). The tailored AI group showed a significantly lower rate of segments with acute PV reconnection than the fixed AI group (8% vs. 5%, p = .007). The tailored AI group showed a trend for shorter ablation time for PVI. One-year AF/atrial tachycardia free survival rate was similar in two groups (87.2% in the fixed AI group and 90.0% in the tailored AI group, p = .606). CONCLUSION: Applying tailored AI based on the LAWT was a feasible and effective strategy to reduce acute PV reconnection after PVI.

Cell wall thickness has phylogenetically consistent effects on the photosynthetic nitrogen-use efficiency of terrestrial plants.

Leaf photosynthetic nitrogen-use efficiency (PNUE) diversified significantly among C3 species. To date, the morpho-physiological mechanisms and interrelationships shaping PNUE on an evolutionary time scale remain unclear. In this study, we assembled a comprehensive matrix of leaf morpho-anatomical and physiological traits for 679 C3 species, ranging from bryophytes to angiosperms, to comprehend the complexity of interrelationships underpinning PNUE variations. We discovered that leaf mass per area (LMA), mesophyll cell wall thickness (Tcwm ), Rubisco N allocation fraction (PR ), and mesophyll conductance (gm ) together explained 83% of PNUE variations, with PR and gm accounting for 65% of those variations. However, the PR effects were species-dependent on gm , meaning the contribution of PR on PNUE was substantially significant in high-gm species compared to low-gm species. Standard major axis (SMA) and path analyses revealed a weak correlation between PNUE and LMA (r2 = 0.1), while the SMA correlation for PNUE-Tcwm was robust (r2 = 0.61). PR was inversely related to Tcwm , paralleling the relationship between gm and Tcwm , resulting in the internal CO2 drawdown being only weakly proportional to Tcwm . The coordination of PR and gm in relation to Tcwm constrains PNUE during the course of evolution.

Thickness measurement of cell walls of closed-cell foams in micro-CT images.

Characterising the microstructure of foams is an important task for improving foam manufacturing processes and building foam numerical models. This study proposed a method for measuring the thickness of individual cell walls of closed-cell foams in micro-CT images. It comprises a distance transform on CT images to obtain thickness information of cell walls, a watershed transform on the distance matrix to locate the midlines of cell walls, identifying the intersections of midlines of cell walls by examining how many regions each pixel on the midlines of cell walls connects with, disconnecting and numbering the midlines of cell walls, extracting the distance values of the pixels on the midlines (or midplanes) of cell walls, and calculating the thickness of individual cell walls by multiplying the extracted distance values by two. Using this method, the thickness of cell walls of a polymeric closed-cell foam was measured. It was found that cell wall thickness measured in 2D images shows larger average values (around 1.5 times) and dispersion compared to that measured in volumetric images.

Leaf optical properties and photosynthesis of fern species with a wide range of divergence time in relation to mesophyll anatomy.

BACKGROUND AND AIMS: For a comprehensive understanding of the mechanisms of changing plant photosynthetic capacity during plant evolutionary history, knowledge of leaf gas exchange and optical properties are essential, both of which relate strongly to mesophyll anatomy. Although ferns are suitable for investigating the evolutionary history of photosynthetic capacity, comprehensive research of fern species has yet to be undertaken in this regard. METHODS: We investigated leaf optical properties, gas exchange and mesophyll anatomy of fern species with a wide range of divergence time, using 66 ferns from natural habitats and eight glasshouse-grown ferns. We used a spectroradiometer and an integrating sphere to measure light absorptance and reflectance by the leaves. KEY RESULTS: The more newly divergent fern species had a thicker mesophyll, a larger surface area of chloroplasts facing the intercellular airspaces (Sc), thicker cell walls and large light absorptance. Although no trend with divergence time was obtained in leaf photosynthetic capacity on a leaf-area basis, when the traits were expressed on a mesophyll-thickness basis, trends in leaf photosynthetic capacity became apparent. On a mesophyll-thickness basis, the more newly divergent species had a low maximum photosynthesis rate, accompanied by a low Sc. CONCLUSIONS: We found a strong link between light capture, mesophyll anatomy and photosynthesis rate in fern species for the first time. The thick mesophyll of the more newly divergent ferns does not necessarily relate to the high photosynthetic capacity on a leaf-area basis. Rather, the thick mesophyll accompanied by thick cell walls allowed the ferns to adapt to a wider range of environments through increasing leaf toughness, which would contribute to the diversification of fern species.

Personalized pulmonary vein antrum isolation guided by left atrial wall thickness for persistent atrial fibrillation.

AIMS: Pulmonary vein (PV) antrum isolation proved to be effective for treating persistent atrial fibrillation (PeAF). We sought to investigate the results of a personalized approach aimed at adapting the ablation index (AI) to the local left atrial wall thickness (LAWT) in a cohort of consecutive patients with PeAF. METHODS AND RESULTS: Consecutive patients referred for PeAF first ablation were prospectively enrolled. The LAWT three-dimensional maps were obtained from pre-procedure multidetector computed tomography and integrated into the navigation system. Ablation index was titrated according to the local LAWT, and the ablation line was personalized to avoid the thickest regions while encircling the PV antrum. A total of 121 patients (69.4% male, age 64.5 ± 9.5 years) were included. Procedure time was 57 min (IQR 50-67), fluoroscopy time was 43 s (IQR 20-71), and radiofrequency (RF) time was 16.5 min (IQR 14.3-18.4). The median AI tailored to the local LAWT was 387 (IQR 360-410) for the anterior wall and 335 (IQR 300-375) for the posterior wall. First-pass PV antrum isolation was obtained in 103 (85%) of the right PVs and 103 (85%) of the left PVs. Median LAWT values were higher for PVs without first-pass isolation as compared to the whole cohort (P = 0.02 for left PVs and P = 0.03 for right PVs). Recurrence-free survival was 79% at 12 month follow-up. CONCLUSION: In this prospective study, LAWT-guided PV antrum isolation for PeAF was effective and efficient, requiring low procedure, fluoroscopy, and RF time. A randomized trial comparing the LAWT-guided ablation with the standard of practice is in progress (ClinicalTrials.gov, NCT05396534).