Lumen Size Research Articles

Design and Evaluation of the SoftSCREEN Capsule for Colonoscopy

Colonoscopy is considered the golden standard for cancer screening of the lower gastrointestinal (GI) tract. Nonetheless, conventional colonoscopy can cause discomfort to patients due to the forces occurring between colonoscopes and the walls of the colon. Robotic solutions have been proposed to reduce discomfort, and improve accessibility and image quality. Aiming at addressing the limitations of traditional and robotic colonoscopy, in this paper, we present the SoftSCREEN System – a novel Soft Shape-shifting Capsule Robot for Endoscopy based on Eversion Navigation. A plurality of tracks surrounds the body of the system. These tracks are driven by a single motor paired with a worm gear and evert from the internal rigid chassis, enabling full-body track-based navigation. Two inflatable toroidal chambers enclosing this rigid chassis and passing through the tracks, cause them to displace when inflated. This displacement can be used to regulate the contact with the surrounding wall, thus enabling traction control and adjustment of the overall system diameter to match the local lumen size. The design of the first tethered prototype at 2:1 scale of the SoftSCREEN system is presented in this work. The experimental results show efficient navigation capabilities for different lumen diameters and curvatures, paving the way for a novel robot capable of robust navigation and reliable control of the imaging, with potential for applications beyond colonoscopy, including gastroscopy and capsule endoscopy.

Abstract Number ‐ 63: A swine model to simulate the mechanism of aspiration thrombectomy.

Introduction Aspiration thrombectomy is an effective technique to recanalize large vessel occlusions (LVO) in stroke patients and has become one of the major techniques. Advancements in technology have enabled the use of catheters with larger lumens and higher aspiration forces; however, the successful reperfusion rate of the first pass remains at 57–63%. This poses a question as to why this rate is still suboptimal when conducting aspiration thrombectomy. We established a swine model for LVO, which provides concurrent fluoroscopic and transmural visualization of real‐time vessel responses during aspiration thrombectomy, to investigate the mechanism of aspiration thrombectomy. Methods Under general anesthesia, a common carotid artery (CCA) and a superficial cervical artery (SCA) of Yorkshire swine (n = 3) were surgically exposed, and an LVO was reproduced by injecting a radiopaque clot analog via a guiding catheter. Each target artery was treated using aspiration catheters with different inner diameters (0.058, 0.068, and 0.088 inches). The CCA group (n = 7) represented large diameter vessels (4‐5mm) simulating a human ICA, and the SCA group (n = 6), with bifurcations, represented small diameter vessels (2‐3mm) simulating a human MCA. To make a consistent clot location in the CCA group, mild, non‐flow‐limiting stenosis was created using a 4‐0 Prolene suture. Fluoroscopy and a high‐resolution digital microscope camera were used simultaneously to monitor angiographic and transmural vessel behavior during the procedure. Average vessel diameter, local blood pressures proximal and distal to the occlusion site, the presence or absence of vessel collapse / reverse flow during the procedures, and pre‐and post‐angiographic findings were evaluated. Results Both fluoroscopic and transmural visualization of mechanical thrombectomy was achieved in all vessels allowing the observation of real‐time arterial wall and clot response during the procedure. The mean blood pressures distal and proximal to the occlusion site showed no significant differences between the two groups. With remote aspiration, all vessels in the SCA group (Mean Diameter: 2.34 ± 0.49mm) showed immediate vessel collapse, and regardless of the lumen size of the catheter, they all failed to recanalize the vessels. Effective clot ingestion was achieved only when direct contact aspiration was applied (5 of 6 vessels). None of the vessels in the CCA group (Mean Diameter: 5.16 ± 0.54 mm) showed vessel collapse during remote aspiration. Six out of 7 vessels (85.7%) treated with remote aspiration showed local reverse flow followed by complete aspiration when the tip of the aspiration catheter was placed 5–20mm away from the clot. One CCA vessel required direct contact aspiration to achieve clot ingestion. Conclusions This swine model to analyze vessel behavior during aspiration thrombectomy may help us understand the mechanism of aspiration thrombectomy. The model may contribute to improving the techniques and the development of new aspiration devices.

Probing and piercing lipid bilayers with DNA nanostructures.

Lipid bilayer membranes are essential in biological cells and typically interact with proteins, such as via membrane-spanning channels. DNA, by contrast, does not usually interact in such a way with biological membranes. Here I show that DNA nanostructures can be rationally designed to either tether to or puncture bilayers. Nanostructures that adhere to the membrane can probe its biophysical properties including elasticity, offering advantages over existing analysis approaches. DNA nanostructures can also be designed to puncture membranes and form synthetic channels. Reflecting the unique advantages of DNA, the synthetic channels outperform biological pores in terms of defined lumen size and open up new biosensing routes. A comparison shows the unique strengths of membrane-interacting protein vs. DNA structures.

Histological evaluation of vascular changes after excimer laser angioplasty for neointimal formation after bare-metal stent implantation in rabbit iliac arteries.

Excimer laser is used to treat coronary artery disease, especially in case of lesions with thrombus and in-stent restenosis (ISR). However, there are no in vivo preclinical studies that have evaluated the pathological reactions of the vessel wall after excimer laser ablation. Bare-metal stents were placed in the external iliac arteries of six healthy rabbits. Twenty-eight days later, excimer laser ablation was performed with low-power (45 (fluency)/25 (rate)) in one side, and high-power (60/40) in the opposite side, followed by optical coherence tomography (OCT) evaluation. Rabbits were sacrificed 15min after the procedure, and histological assessment was performed. Morphometry analysis of OCT showed similar stent and lumen size between low-power and high-power group. Histological evaluation suggested endothelial cell loss, fibrin deposition, and tissue loss. The low-power group showed significantly less pathological changes compared with the high-power group: angle of endothelial cell loss, 32.4° vs. 191.7° (interquartile range, 8.8°-131.7° vs. 125.7°-279.5°; p < 0.01); fibrin deposition, 1.1° vs. 59.6° (0.0°-70.4° vs. 31.4°-178.4°; p = 0.03); and tissue loss 0.0° vs. 18.2° (0.0°-8.7° vs. 0.0°-42.7°; p = 0.03). The pathological changes in neointima were more prominent after high-power excimer laser ablation than after low-power excimer laser. To improve safety in clinical practice, understanding the pathological changes of tissues after excimer laser in lesions with ISR is essential.

Efficacy of scissor-type knife for endoscopic submucosal dissection: a systematic review and meta-analysis.

Endoscopic submucosal dissection (ESD) is an effective resection technique for early cancers and large gastrointestinal luminal lesions. However, ESD is technically challenging, with the potential for severe adverse events. Scissor-type ESD (ST-ESD) knives with an inner cutting edge and an electrically insulated external coating could mitigate some of these risks. This study aimed to evaluate the performance of ST electrosurgical knives when used for ESDs. Electronic databases were queried for studies from January 2005 through December 2022 evaluating the performance of ST-ESD knives. Fixed- and random-effects models were used to calculate pooled proportions. Heterogeneity was assessed using the I2 test and by constructing funnel plots, while bias was calculated using Egger and Harbord bias indicators. Final analysis included data from 17 studies comprising 1652 ESD procedures. The pooled en bloc resection rate and R0 resection rate were 97.94% (95% confidence interval [CI] 97.20-98.57) and 94.32% (95%CI 93.11-95.43), respectively. The main adverse events were perforation and delayed post-procedural bleeding, with pooled rates of 1.07% (95%CI 0.63-1.62) and 1.86% (95%CI 1.26-2.56), respectively. There was no heterogeneity, as indicated by an I2 score of 0% (95%CI 0-44.50%). The mean procedure time was 67.45 min (95%CI 58.01-76.89). Our analysis shows that ST-ESD knives deliver consistently good performance across various locations in the gastrointestinal lumen and lesion sizes, with a good safety profile. This could be particularly appealing to newer adopters of ESD.

Aerobic exercise increases brain vessel lumen size and blood flow in young adults with elevated blood pressure. Secondary analysis of the TEPHRA randomized clinical trial

ImportanceCerebrovascular changes are already evident in young adults with hypertension and exercise is recommended to reduce cardiovascular risk. To what extent exercise benefits the cerebrovasculature at an early stage of the disease remains unclear. ObjectiveTo investigate whether structured aerobic exercise increases brain vessel lumen diameter or cerebral blood flow (CBF) and whether lumen diameter is associated with CBF. DesignOpen, parallel, two-arm superiority randomized controlled (1:1) trial in the TEPHRA study on an intention-to-treat basis. The MRI sub-study was an optional part of the protocol. The outcome assessors remained blinded until the data lock. SettingSingle-centre trial in Oxford, UK. ParticipantsParticipants were physically inactive (<150 min/week moderate to vigorous physical activity), 18 to 35 years old, 24-hour ambulatory blood pressure 115/75 mmHg-159/99 mmHg, body mass index below 35 kg/m2 and never been on prescribed hypertension medications. Out of 203 randomized participants, 135 participated in the MRI sub-study. Randomisation was stratified for sex, age (<24, 24–29, 30–35 years) and gestational age at birth (<32, 32–37, >37 weeks). InterventionStudy participants were randomised to a 16 week aerobic exercise intervention targeting 3×60 min sessions per week at 60 to 80 % peak heart rate. Main outcomes and Measurescerebral blood flow (CBF) maps from ASL MRI scans, internal carotid artery (ICA), middle cerebral artery (MCA) M1 and M2 segments, anterior cerebral artery (ACA), basilar artery (BA), and posterior cerebral artery (PCA) diameters extracted from TOF MRI scans. ResultsOf the 135 randomized participants (median age 28 years, 58 % women) who had high quality baseline MRI data available, 93 participants also had high quality follow-up data available. The exercise group showed an increase in ICA (0.1 cm, 95 % CI 0.01 to 0.18, p =.03) and MCA M1 (0.05 cm, 95 % CI 0.01 to 0.10, p =.03) vessel diameter compared to the control group. Differences in the MCA M2 (0.03 cm, 95 % CI 0.0 to 0.06, p =.08), ACA (0.04 cm, 95 % CI 0.0 to 0.08, p =.06), BA (0.02 cm, 95 % CI −0.04 to 0.09, p =.48), and PCA (0.03 cm, 95 % CI −0.01 to 0.06, p =.17) diameters or CBF were not statistically significant. The increase in ICA vessel diameter in the exercise group was associated with local increases in CBF. Conclusions and RelevanceAerobic exercise induces positive cerebrovascular remodelling in young people with early hypertension, independent of blood pressure. The long-term benefit of these changes requires further study. Trial RegistrationClinicaltrials.gov NCT02723552, 30 March 2016

Surgical Management of Post-Intubation Tracheal Injuries: A Single-Center Experience from Nepal

Introduction: Despite various improvements in technology and patient care, tracheal intubation and tracheostomy still result in significant tracheal injuries like stenosis and airway fistula. Pressure necrosis by the inflated balloon is the commonest culprit. Post-intubation tracheal stenosis is a major indication for tracheal resection and anastomosis. This study was done to find out the indications and results of surgery for post-intubation tracheal lesions. Methods: It was a descriptive observational study of patients with post- intubation tracheal lesions managed in Manmohan Cardiothoracic Vascular and Transplant Center over a period of 20 years (2001 to 2021). Results: Twenty-five patients were treated for post-intubation tracheal lesions. Four had isolated tracheo-esophageal fistula (TEF); eighteen had an isolated tracheal stenosis and three had both. Most had a tracheal resection and end-end anastomosis (REEA) via a cervical approach, resecting an average of 2.7 cm of tracheal length. The average size of stenotic lumen was 4.32 mm. There were no operative deaths. Two patients expired within a month of surgery: one due to fatal restenosis and the other due to sepsis. There were a few immediate and a few long-term complications. The average follow-up period was 5 years. Conclusion: Among the various post-intubation lesions, tracheal stenosis is the commonest indications for surgery. The management is challenging but safe and feasible, with a multidisciplinary team approach.

Highly Selective Transmembrane Transport of Exogenous Lithium Ions through Rationally Designed Supramolecular Channels.

Lithium ions have been applied in the clinic in the treatment of psychiatric disorders. In this work, we report artificial supramolecular lithium channels composed of pore-containing small aromatic molecules. By adjusting the lumen size and coordination numbers, we found that one of the supramolecular channels developed shows unprecedented transmembrane transport of exogenous lithium ions with a Li+ /Na+ selectivity ratio of 23.0, which is in the same level of that of natural Na+ channels. Furthermore, four coordination sites inside channels are found to be the basic requirement for ion transport function. Importantly, this artificial lithium channel displays very low transport of physiological Na+ , K+ , Mg2+ , and Ca2+ ions. This highly selective Li+ channel may become an important tool for studying the physiological role of intracellular lithium ions, especially in the treatment of psychiatric disorders.

Highly Selective Transmembrane Transport of Exogenous Lithium Ions through Rationally Designed Supramolecular Channels

AbstractLithium ions have been applied in the clinic in the treatment of psychiatric disorders. In this work, we report artificial supramolecular lithium channels composed of pore‐containing small aromatic molecules. By adjusting the lumen size and coordination numbers, we found that one of the supramolecular channels developed shows unprecedented transmembrane transport of exogenous lithium ions with a Li+/Na+ selectivity ratio of 23.0, which is in the same level of that of natural Na+ channels. Furthermore, four coordination sites inside channels are found to be the basic requirement for ion transport function. Importantly, this artificial lithium channel displays very low transport of physiological Na+, K+, Mg2+, and Ca2+ ions. This highly selective Li+ channel may become an important tool for studying the physiological role of intracellular lithium ions, especially in the treatment of psychiatric disorders.

929: ENDOBRONCHIAL METASTASIS FROM OSTEOSARCOMA: TREATMENT WITH CRYOTHERAPY AND ARGON PLASMA COAGULATION

Introduction: Osteosarcoma is the most common primary malignant tumor of the bone. Pulmonary metastasis is frequently seen as a relapse in approximately 80% of patients; however, endobronchial metastasis is very rare. We present a case of endobronchial osteosarcoma in a young man. Description: A 20-year-old male non-smoker with a history of treatment-refractory metastatic osteosarcoma presented with shortness of breath, dry cough, and episodes of hemoptysis for a few days. On presentation, vital signs were significant for tachycardia (HR 113/min) and tachypnea (RR 24/min). Chest CT scan showed no pulmonary embolism but revealed bilateral pulmonary and pleural metastases with severe narrowing of the right upper lobe pulmonary artery segmental branches secondary to metastases. At fiberoptic bronchoscopy, there was complete obstruction of the right upper lobe apical and posterior segments by a dark red vascular appearing tumor. Cryotherapy was performed to destroy abnormal tissue, along with balloon occlusion. Coagulation using an Argon Plasma Coagulation (APC) was performed in the lung. Post-treatment findings showed improved lumen size. The patient tolerated the procedure well and had remarkable improvement in symptoms. Biopsy of the endobronchial tumor showed metastatic sarcoma, similar to the patient’s prior high-grade pleomorphic sarcoma. Discussion: Airway obstruction may be extrinsic, intrinsic, or mixed; fixed or dynamic; and benign or malignant. It may present with a variety of symptoms ranging from mild shortness of breath to respiratory failure. There are few published case reports of endobronchial obstruction secondary to osteosarcoma. Bronchoscopy (either rigid or flexible) is always necessary for assessing airway obstruction. Dilation is immediately effective for intrinsic and extrinsic compression, but results are typically not sustained. Cryotherapy relies on repeated freeze-thaw cycles using extreme cold (below –40°C) to destroy tissue and tumor and can be used via both rigid and flexible bronchoscopes. APC is a mode of noncontact electrocoagulation that is increasingly used as an alternative to contact electrocautery and noncontact laser therapy. Often, the best therapeutic approach appears to include a combination of several treatment approaches as demonstrated in our patient.

Case-Control Study of 3D Morphology in Isolated Mesenteric Artery Dissection.

Isolated mesenteric artery dissection (IMAD) is uncommon and has not been investigated in detail. This study aimed to accurately identify the morphological differences of IMAD patients with control individuals using a detailed 3D volumetric analysis. In this retrospective case-control study, cases were patients with acute symptomatic IMAD treated in a French intestinal stroke center between January 2016 and November 2019. Case-control matching was (1:3) by age, gender, and body mass index (BMI). The semi-automatic morphological analysis of the mesenteric artery included volumetric measurements of the true and false lumen size, the centerline curvature and the 3D aortomesenteric angles. Seventeen IMAD cases (mean age 56 ± 4years, 94% men) were matched with 51 controls. The mean overall lumen (OL) volume was higher in IMAD patients as compared to controls (+ 64%, p < 0.001). In the same way, the mean OL cross-sectional area and diameters were higher in IMAD patients: + 77% for OL area (< 0.001) and + 34% for OL diameters (< 0.001). Meanwhile, no significant difference was found in terms of true lumen (TL) volume (p = 0.16) or cross-sectional area (p = 0.30) between IMAD patients and controls, whereas the mean TL diameter was lower in the IMAD group (p < 0.05). Patients with acute mesenteric ischemia had a lower [TL/OL volume] ratio (45% vs. 59%, p < 0.05) and longer dissections (63mm vs. 48mm, p < 0.01). The 3D aortomesenteric angle was significantly higher in IMAD patients at both 2cm (p < 0.01) and 4cm (p < 0.05) from the ostium. Using an original 3D semi-automated analysis, this study shows that IMAD induces significant morphological changes compared to control individuals: a larger aortomesenteric 3D angle, an increased overall volume and area. IMAD patients with acute mesenteric ischemia presented with a more severe morphological profile.

Endovascular versus neurosurgical aneurysm treatment: study protocol for the development and validation of a clinical prediction tool for individualised decision making

IntroductionTreatment decisions for aneurysmal subarachnoid haemorrhage patients should be supported by individualised predictions of the effects of aneurysm treatment. We present a study protocol and analysis plan for the development...

Antibiofilm and enhanced antibiotic delivery by halloysite nanotubes architected dental implant against periodontitis

Dental implant failure remains a predominant problem; poor integration and biofilm formation are the major glitches. The surface modification of implant improves it antibiotic delivery performance and nanostructure incorporation facilitates the versatile behavior. Herein, we have prepared PCPP functionalized HNT and it encapsulated with AMO and MS. FTIR confirms the PCPP coating over the HNT by formation of new peaks at 1640 and 1580 cm−1. Higher stability of HNT nanocomposites was denoted by its zeta value – 45.24 mV. The maximum release of 58% (AMO) and 62% (MS) from the nanocomposites was achieved at the acidic pH. PCPP coated MS-HNT nanocomposites forms lumen size ranging from 15 to 20 nm with uniform surface morphology. Simultaneously, bioactive MS-AMO-PCPP-HNT was deposited on the Ti–6Al–4V screw implant via electrophoretic deposition. The coating of HNT nanocomposites on titanium surface provides 7.24 μm thickness and adhesive strength of 24.6 MPa. After EPD of MS-AMO-PCPP-HNT on Ti–6Al–4V screw, the surface is fully covered by adequate bonding, stable coating, biocompatible and long-lasting antibacterial efficacy. The potentiodynamic study in the SBF shows that the coating provided corrosion protection of the screw. The coated Ti–6Al–4V screw surface composition enhances the biomineralization, promote the cell adhesion, proliferation and promote the soft tissue healing. Compared to the HNT, PCPP-HNT nanocomposites induces the ALP production, increase the cell proliferation rate at 20 μg/mL. In flow cytometry, biocompatible HNT nanocomposites exhibited lesser dead cells of 0.56%. HNT nanocomposites inhibit the 96% (E.coli) and 97% (S. aureus) bacterial inhibition and the rate were higher compared to the AMO alone. Also reduction of 78% of Porphyromonas gingivalis biofilm biomass, the coating is powerfully active against the both pathogenic microbes and bacterial biofilm of peri-implant infection. The nano-architected coating of Ti–6Al–4V screw has great potential in dental implantology.

Ultrastructural destruction of neurovascular unit in experimental cervical spondylotic myelopathy.

The pathogenesis of cervical spondylotic myelopathy (CSM) remains unclear. This study aimed to explore the ultrastructural pathology of neurovascular unit (NVU) during natural development of CSM. A total of 24 rats were randomly allocated to the control group and the CSM group. Basso-Beattie-Bresnahan (BBB) scoring and somatosensory evoked potentials (SEP) were used as functional assessments. Hematoxylin-eosin (HE), toluidine blue (TB), and Luxol fast blue (LFB) stains were used for general structure observation. Transmission electron microscopy (TEM) was applied for investigating ultrastructural characteristics. The evident compression caused significant neurological dysfunction, which was confirmed by the decrease in BBB score and SEP amplitude, as well as the prolongation of SEP latency (P < 0.05). The histopathological findings verified a significant decrease in the amount of Nissl body and myelin area and an increase in vacuolation compared with the control group (P < 0.05). The TEM results revealed ultrastructural destruction of NVU in several forms, including: neuronal degeneration and apoptosis; disruption of axonal cytoskeleton (neurofilaments) and myelin sheath and dystrophy of axonal terminal with dysfunction mitochondria; degenerative oligodendrocyte, astrocyte, and microglial cell inclusions with degenerating axon and dystrophic dendrite; swollen microvascular endothelium and loss of tight junction integrity; corroded basement membrane and collapsed microvascular wall; and proliferated pericyte and perivascular astrocytic endfeet. In the CSM group, reduction was observed in the amount of mitochondria with normal appearance and the number of cristae per mitochondria (P < 0.05), while no substantial drop of synaptic vesicle number was seen (P > 0.05). Significant narrowing of microvascular lumen size was also observed, accompanied by growth in the vascular wall area, endothelial area, basement membrane thickness, astrocytic endfeet area, and pericyte coverage area (rate) (P < 0.05). Altogether, the findings of this study demonstrated ultrastructural destruction of NVU in an experimental CSM model with dorsal-lateral compression, revealing one of the crucial pathophysiological mechanisms of CSM.

Abstract 15731: Rpl13a Small Nucleolar RNAs Promote Atherosclerosis and Oxidative Stress

Reactive oxygen species (ROS) exacerbate atherosclerosis (athero). ROS levels are elevated by specific non-coding, small nucleolar (sno) RNAs encoded within introns of the Rpl13a gene. We therefore tested the hypothesis that these snoRNAs promote athero, using “snoKO” mice deficient in Rpl13a snoRNAs, but not in Rpl13a itself. ROS levels assessed by CellROX Orange were 35% lower in snoKO than snoRNA +/+ aorta frozen sections ( p &lt;0.01). After 14 wk on Western diet, female snoKO/ Apoe -/- unexpectedly showed total cholesterol levels 20% higher than Apoe -/- mice in (1,046 vs 869 mg/dl, p &lt;0.05). Despite this, neointimal lesions in brachiocephalic artery (BCA) cross-sections were 50% smaller in snoKO/ Apoe -/- than in Apoe -/- mice, and lumen size was 45% larger (both p &lt;0.01, n=8/group). Similar data were obtained in males: snoKO/ Apoe -/- mice had 40% smaller BCA lesion areas ( p &lt;0.02, n=8/group). After being stained for cholesteryl ester with BODIPY, for ACTA2 by immunofluorescence and for DNA (Hoechst), BCAs from female snoKO/ Apoe -/- mice (n=9) demonstrated 50% less foam cell-positive and 95% more ACTA2 + area, 40% less necrotic core area, and a 60% lower prevalence of ACTA2 + foam cells ( p &lt;0.05 for each). Thus, Rpl13a snoRNAs promote vascular ROS and athero. Assessed by MitoSOX Red, ROS levels were 25% lower in snoKO than WT M1-polarized bone marrow-derived Mϕs in vitro (n=3, p&lt;0.05). To identify mechanisms linking the Rpl13a snoRNAs to ROS and athero, we performed LC-MS/MS on WT and snoKO aortic SMCs. COX4I2 was expressed 5.7-fold higher in snoKO than WT SMCs by MS/MS, and 2.5-fold higher in snoKO SMCs by immunoblot (n=3/group, p &lt;0.05). As part of mitochondrial complex IV, COX4I2 lowers cellular ROS levels. We used CRISPR/Cas9 to create 293T cells lacking either the RPL13a -snoRNA U34A or the irrelevant snoRNA U25 . With mRNA from these cells we performed reverse transcription at low [dNTP] followed by qPCR (RTL-P) for COX4I2 . Inversely proportional to the degree of mRNA 2’- O -methylation (mediated by snoRNAs), the RTL-P efficiency was 4-fold higher in U34A -knockout than control cells (3 clones/genotype, p &lt;0.01). Thus, COX4I2 mRNA appears to be regulated by RPL13A -snoRNA-guided 2’- O -methylation in a manner that could link Rpl13a snoRNAs, vascular ROS, and athero.

Pollen morphology of some selected species of the tribes Brassiceae, Conringieae, Isatideae, and Plagiolobeae (Brassicaceae) in Iran, and its taxonomic significance

ABSTRACT Pollen morphology of 12 species, representing tribes Brassiceae, Conringieae, Isatideae, and Plagiolobeae genera were studied using light microscopy (LM) and scanning electron microscopy (SEM). The results demonstrated that the polar diameter, pollen exine ornamentation, mesocolpium width, and exine thickness have important systematic significance. The results revealed that pollen grains in these genera were tricolpate and their shapes varied from prolate to perprolate, with the polar axis ranging from 30.28 to 41.05 µm and the equatorial axis from 17.21 to 23.36 µm. However fine details are characteristic of distinguishing pollen grains in the species of the genera. The exine ornamentation varied among genera within the tribes and species within the same genus. Three pollen types are distinguished based on lumen size. All the studied tribes’ pollen were heterogeneous with ornamentation reticulate, ornamentation microreticulate (Conringia orientalis, Plagioloba derakii), and ornamentation macroreticulate (Moricandia sinaica). The exine thickness ranged from 0.75 to 2.60 µm. Pollen characteristics support: (i) two distinct pollen types viz., Conringia austriaca and Iljinskaea planisiliqua types in all four tribes; (ii) the similarity of the pollen shape tribes Isatideae and Brassiceae; (iii) confirmation of the transfer of P. crenulata from Zuvanda to Plagioloba, and I. planisiliqua from Conringia to Iljinskaea, respectively. Plagioloba clavata have great variations in the pollen morphological characters in Plagioloba and needs to be further studied. The key to the species of the genera was also provided.

A safe breeding ground: genetically improved maritime pine for growth and stem form has more efficient but not more vulnerable xylem.

Through repeated cycles of selection and recombination, tree breeding programs deliver genetically improved varieties for a range of target characteristics such as biomass production, stem form, resistance to biotic stresses, wood properties, etc. However, in the context of increased drought and heat waves, it is not yet known whether growth performance will impede drought resistance. To address this question, we compared the hydraulic properties, such as hydraulic efficiency and hydraulic safety, in four varieties over successive varieties of genetically improved maritime pines (i.e., Pinus pinaster Aït.) for growth and stem form. We measured 22 functional traits related to hydraulic efficiency, hydraulic safety, xylem anatomy and wood density. We found that improved varieties presented higher hydraulic conductivity with larger tracheid lumen size and tracheid lumen fraction, and smaller wall thickness reinforcement and tracheid density, but not at the cost of reduced embolism resistance. The reported absence of trade-off between hydraulic conductivity and embolism resistance is a strong asset to improve biomass productivity, through increased hydraulic efficiency, without impacting drought resistance, and should enable new maritime pine varieties to cope with a drier climate. Our study is one of the first to reveal the hydraulic mechanisms over successive varieties of genetic improvement for tree growth. It provides guidelines for sustainable forest management through breeding for other forest tree species.

Interobserver Variability Between Expert, Experienced, and Novice Operator Affects Interpretation of Optical Coherence Tomography and 20 MHz Intravascular Ultrasound Imaging

BackgroundVessel sizing and calcium detection by intracoronary imaging informs optimal strategy during coronary interventions, but image interpretation and analysis software vary considerably between platforms. We compared the interobserver variability of clinicians with a range of experience in assessing co-registered optical coherence tomography (OCT) and 20 MHz solid state intravascular ultrasound (IVUS) vessel/ lumen geometry and quantitative plaque data. MethodsCo-registered OCT and IVUS frames at the minimum lumen area (MLA) and 5 frames at 2 mm intervals upstream and downstream were read blinded by an expert, consultant, interventional fellow and registrar to define vessel and lumen sizes, plaque characteristics (arc of calcium and lipid) and presence of OCT-defined thin-capped fibroatheroma (TCFA). ResultsOverall, 143 paired frames of OCT and IVUS were analysed. Excellent consistency was seen for all OCT measures of vessel/luminal geometry irrespective of experience (all intraclass correlation coefficients (ICC) >0.89). Inexperience compromised ICC for IVUS (lumen area ICC 0.56; vessel size ICC 0.65) and overestimated lumen size compared to expert (p < 0.001). Calcium arc agreement for OCT and IVUS was equally strong for all but the most inexperienced reader (ICC >0.84). OCT lipid arc agreement was moderate for experienced readers but poor for all grades of reader with IVUS (ICC 0.24–0.43). OCT-TCFA agreement was moderate between expert and consultant (κ = 0.55) and poor for less experienced readers. ConclusionOCT dimensions are minimally affected by observer experience and more consistent than IVUS. Inexperienced readers oversize with IVUS. Calcium arc is dependably assessed by IVUS and OCT by all but the most inexperienced reader.

Endovascular treatment of type „A“ and type „B“ dissection of the aorta

During the period from March 2014 to May 2018, endovascular treatment of aortic dissection type A and type B was carried out in a total of 70 patients. Patients were divided into two groups, aortic dissection type A (14 patients) and type B (56 patients), a group-by-group descriptive analysis was conducted, and then a comparison was done between the two patient groups. &amp;nbsp;The aim of the study was to establish the effective use of endovascular treatment in type A and type B aorta dissection. As a result of the survey, data on the demographic characteristics and risk profile of these patients are accumulated for the first time in Bulgaria. Endovascular treatment options for the treatment of aortic dissection type A and type B, as well as malperfusion syndrome, are examined, demonstrating their effectiveness and safety. As a result of the study, it is proven that endovascular treatment in aortic dissection type A and type B leads to a significant increase in the size of the true lumen and reduction of the false lumen, which leads to an improvement in perfusion and reduces the risk of developing an aneurysm and rupture. &amp;nbsp;The presence of endoleak and persistent communication between the false and the real lumen are the most common causes of re-intervention, such as endovascular options are most often the first line for their dealing and are proven to be effective and safe. &amp;nbsp;Treatment of dissection of the aorta type A and B is not a one-time act, but requires periodic diagnostic control and, if necessary, surfery and/or endovascular corrections of the complications that have arisen.

PH-Responsive Polyelectrolyte Coatings that Enable Catheter-Mediated Transfer of DNA to the Arterial Wall in Short and Clinically Relevant Inflation Times.

We report the design and characterization of pH-responsive polymer coatings that enable catheter balloon-mediated transfer of DNA to arterial tissue in short, clinically relevant inflation times. Our approach exploits the pH-dependent ionization of poly(acrylic acid) (PAA) to promote disassembly and release of plasmid DNA from polyelectrolyte multilayers. We characterized the contact transfer of multilayers composed of PAA, plasmid DNA, and linear poly(ethyleneimine) (LPEI) identified as promising in prior studies on the delivery of DNA to arterial tissue. In contrast to thinner films evaluated previously, we found thicker coatings composed of 32 repeating (LPEI/PAA/LPEI/DNA)x tetralayers to swell substantially in physiologically relevant media (in PBS; pH = 7.4). In some cases, these coatings also disintegrated or delaminated rapidly from their underlying substrates, suggesting the potential for enhanced balloon-mediated transfer. We developed a technically straightforward agarose gel-based hole-insertion model to characterize factors (inflation time, lumen size, etc.) that influence contact transfer of DNA when film-coated balloons are inflated into contact with soft surfaces. Those studies and the results of in vivo experiments using small animal (rat) and large animal (pig) models of peripheral arterial injury revealed catheters coated with these materials to promote robust contact transfer of DNA to soft hydrogel surfaces and the luminal surfaces of arterial tissue using inflation times as short as 30 s. These short inflation times are relevant in the context of clinical vascular interventions in peripheral arteries. Additional studies demonstrated that contact transfer of DNA using these short times can promote subsequent dissemination and transport of DNA to the medial tissue layer, suggesting the potential for use in therapeutically relevant applications of balloon-mediated gene transfer.