Leaflet Size Research Articles

Numerical taxonomy on varieties of Adansonia digitata L.

Variations in the morphological features of Adansonia digitata L. were studied, which may be used for the delimitation of varieties in the species. The wide range of uses of these naturalised trees in the world have in recent time witnessed increasing demand of their foliar, bark, root, fruit and seed products in nutritional, fibre and medical applications. The upsurge demand for these products needs to be balanced with new varieties of improved performance to meet the supply chain. To achieve this, the present study was aimed at setting the foundation of variability analysis based on morphological features to detect promising varieties for mapping out of future breeding schemes of this multi-purpose tree. The fresh specimens were collected in open vegetation, plantations, houses and bushy areas from mature plant stands in Sudan and Guinea savannah of Nigeria. Both qualitative and quantitative characters studied, coded and subjected to cluster analysis. Some morphological characters indicated close affinity amongst the varieties of A. digitata. Features of taxonomic importance amongst the varieties of A. digitata include leaf surface, pod surface, leaf stalk surface, pod surface, pod end form, pod colour, pod size, stalk size, number of seed per pod, leaf size, seed size, occurrence of leaflet number and leaflet size. Within the species, there is evidence indicating the existence of a number of local types differing in habit, vigour, size, and quality of the fruits and vitamin content. These features were considered to be taxonomically relevant in the delimitation of these varieties. Numerical analysis of the qualitative and quantitative characters data using cluster analysis – average linkage, single linkage, complete linkage and centroid methods delimit all the Operational Taxonomic Units (OTUs) into four varieties hence, infraspecific classification of A. digitata is hereby proposed.

Morphometry and aberrant morphology of the adult human tricuspid valve leaflets.

The tricuspid valve complex has been studied since the beginning of the twentieth century, and variations in the structural orientation of the tricuspid leaflets has been reported before, as the occurrence of accessory leaflets poses a major problem during surgeries related to the tricuspid valve. In this study, 36 adult formalin-fixed human hearts were analyzed to compare the number, form and size of the tricuspid leaflets. The result shows that in right ventricles, the number of leaflets can vary from the routine three to as many as seven, and the localization of such accessory leaflets of the tricuspid valve differs between specimens. Five leaflet forms were the most common, and the 'typical' form of tricuspid valves with no accessory leaflets was only present in a small percentage of the cases studied. Measurements of the main and accessory leaflets showed that the anterior leaflets were the largest, followed by the inferior leaflets, while the septal and the accessory leaflets were the smallest in size. On the basis of these results, it is suggested that three leaflets of the tricuspid valve are relatively uncommon, with frequent occurrences of accessory leaflets. The multicuspidal form of the tricuspid valve therefore raises concern about understanding the functional and physiological significance of the accessory leaflets.

ERIOPHYID MITES INHABITING AMERICAN ELDERBERRY

Identification and control of pests is important as American elderberry (Sambucus nigra subsp. Canadensis) production increases in the United States. Two genera of eriophyid mites, Phyllocoptes wisconsinensis and Epitrimerus trilobus have been described taxonomically and are known to cause foliar damage on elderberry plants. However, mites have not been examined in commercial plantings in Missouri. Thus, specimens were collected from American elderberry leaflets at two locations, Mt. Vernon and Hartsburg, MO, from April 2012 to January 2013. Mite-induced damage varied by location. P. wisconsinensis collected from Mt. Vernon induced curling of leaflet margins with erinea (i.e., enlarged leaf trichomes). In contrast, mites from Hartsburg reduced leaflet size and induced interveinal puckering of plant tissue. Examination of these mites using environmental scanning electron microscopy revealed a previously undescribed fusiform eriophyid mite species. Key features used to identify mites included prodorsal shield anatomy, leg morphology, and genital cover flap structure. Overwintering mites remained on plants under bud scales at Hartsburg and were quantified by bud position. The total average number of mites at all nodes on each plant was 23 in mid-January. Nodes 4 to 6, located near the terminal growing point of last season’s growth, had the greatest average numbers of mites on buds. Terminal buds and those at nodes 12 and 13, located near the soil surface, had the fewest mites.

Pregnancy-induced remodeling of collagen architecture and content in the mitral valve.

Pregnancy produces rapid, non-pathological volume-overload in the maternal circulation due to the demands of the growing fetus. Using a bovine model for human pregnancy, previous work in our laboratory has shown remarkable pregnancy-induced changes in leaflet size and mechanics of the mitral valve. The present study sought to relate these changes to structural alterations in the collagenous leaflet matrix. Anterior mitral valve leaflets were harvested from non-pregnant heifers and pregnant cows (pregnancy stage estimated by fetal length). We measured changes in the thickness of the leaflet and its anatomic layers via Verhoeff-Van Gieson staining, and in collagen crimp (wavelength and percent collagen crimped) via picrosirius red staining and polarized microscopy. Collagen concentration was determined biochemically: hydroxyproline assay for total collagen and pepsin-acid extraction for uncrosslinked collagen. Small-angle light scattering (SALS) assessed changes in internal fiber architecture (characterized by degree of fiber alignment and preferred fiber direction). Pregnancy produced significant changes to collagen structure in the mitral valve. Fiber alignment decreased 17% with an 11.5° rotation of fiber orientation toward the radial axis. Collagen fiber crimp was dramatically lost, accompanied by a 53% thickening of the fibrosa, and a 16% increase in total collagen concentration, both suggesting that new collagen is being synthesized. Extractable collagen concentration was low, both in the non-pregnant and pregnant state, suggesting early crosslinking of newly-synthesized collagen. This study has shown that the mitral valve is strongly adaptive during pregnancy, with significant changes in size, collagen content and architecture in response to rapidly changing demands.

The taxonomic affinity of Carum piovanii Chiov. and some Bunium species (Apiaceae)

The systematic position of three Apiaceae taxa, Carum piovanii, Bunium nothum and Bunium kandaharicum, is clarified based on morphological and nrITS sequence data. The phylogenetic analyses place C. piovanii within the African peucedanoid genus, Afroligusticum and not with its congeners. Although C. piovanii differs considerably from Afroligusticum in underground organs (spindle-shaped or subcylindrical tubers vs. rhizomatous woody rootstocks), size of leaflets (up to 4mm long vs. over 8mm long), and petal color (white vs. mostly greenish or yellow), it is similar carpologically (obtuse-keeled dorsal ribs and narrowly-winged marginal ribs). As a result the new combination Afroligusticum piovanii is proposed. A new section, Austrobunium, is described to accommodate the South Indian B. nothum based on the well-developed calyx teeth not found in the rest of the genus. The Afghanian species, B. kandaharicum, is reduced into synonym with Elwendia stewartiana.

CO2 Enrichment at Night Affects the Growth and Yield of Common Beans

ABSTRACTMany experiments to determine the crop yield increase expected with rising atmospheric carbon dioxide concentration added carbon dioxide only during the daytime, without tests of whether elevation of carbon dioxide at night affected plant growth. In this experiment, two cultivars of common bean (Phaseolus vulgaris L.) were grown in the field for 4 yr in open‐top chambers in which CO2 was added during the day or the night, both day and night, or not at all. CO2 was added to increase the concentration by 180 μmol mol−1 above that of the ambient outside air, which averaged 392 μmol mol−1 during the daytime and 503 μmol mol−1 at night. In the two cultivars, the average increase in seed yield above the ambient CO2 treatment was 42% with daytime CO2 enrichment and 77% with continuous enrichment. In both cultivars, continuous CO2 enrichment increased the area of individual leaflets by about 40% compared with daytime enrichment. Leaflet size was the same with daytime CO2 enrichment and with no enrichment. In one of the cultivars, nighttime CO2 elevation alone increased leaflet size and seed yield. The results indicated that CO2 enrichment at night had important consequences for the growth and yield of these bean cultivars, and that daytime‐only CO2 enrichment greatly underestimated the yield increase likely to occur with rising atmospheric CO2 concentrations.

Imaging Challenges in Secondary Mitral Regurgitation

Chronic secondary mitral regurgitation (SMR) is a complex entity that is often clinically underappreciated.1 It complicates either ischemic heart disease or dilated cardiomyopathy; its prevalence varies among series but may reach ≤50% in patients with heart failure.2 When present, SMR may exhibit a broad range of severity and confers an adverse prognosis, which is worse with increasing severity of mitral regurgitation (MR).3,4 The management of SMR poses a unique set of challenges, based partly on the complexity of the valve disorder and the still-evolving adoption of the optimal therapeutic approach.5 Noninvasive imaging and, in particular, echocardiography, plays a critical role for the initial and longitudinal assessment, for individual risk stratification and outcome prediction, and for guiding intervention in patients with chronic SMR.6 SMR develops because of a combination of mitral leaflet tethering secondary to left ventricular (LV) dilatation/deformation with papillary displacement/discoordination, annular dilatation/dysfunction, insufficient LV-generated closing forces attributable to reduction of LV contractility, and global LV/papillary muscle dyssynchrony.1,5 Tethering of the mitral leaflets is the principal lesion of SMR and results in restriction of systolic leaflet motion, namely type IIIb of Carpentier’s classification. SMR does not typically occur in global LV dysfunction without tethering. However, once tethering occurs, leaflet closure is further impaired by LV dysfunction because there is decreased force opposing tethering.6–9 The key event in the pathogenesis of SMR is the distortion of normal LV geometry—regional and global LV remodeling—with subsequent apical and lateral displacement of papillary muscles, which, in turn, draws the chordae tendineae away from the line of coaptation.7,8 The extent of LV systolic dysfunction and dilatation is weakly correlated to the degree of SMR unless accompanied by geometric distortion in the region of the papillary muscles.1,9 …

Virtual legume: a model to simulate the morphogenesis and shading ability of chickpea cultivars

Plant architecture and light models are one of the in silico tools for investigating the distribution of light under plant canopies with different architectures. Weed researchers and crop breeders can use such models to investigate the interaction of different canopy architectures of crops with light radiation and their effect on weed phenology. Improving the shading ability of the legume crops such as chickpea is one of the ways to control weeds. In order to simulate three-dimensional (3D) architecture of chickpea over time, a 3D digitizer system was used to record the plant morphology, topology, and geometry non-destructively. Models are expressed using the Lindenmayer systems (L-systems) formalism. A ray tracing program is used to estimate the shading ability of different architectures of chickpea. Model demonstrated that features such as leaflet size and number of branches are more important in improving shading ability in chickpea than the branching angle.

Highly photoactive anatase foams prepared from lyophilized aqueous colloids of peroxo-polytitanic acid

Peroxo-polytitanic acid foams annealed at temperature above 500°C lose volatile components and excess of oxygen providing anatase in the form of thin leaves consisting of intergrown nanocrystalline anatase particles which transform at temperatures above 850°C to rutile. The size and shape of the initial leaflets forming the foam is preserved up to ∼900°C. We observed that the annealed material is highly photoactive, owing to highly anisotropic shape of anatase aggregates and their perfect crystallinity. Outstanding photocatalytic activity determined by measuring the kinetics of degradation of Methylene Blue (MB) and 4-chlorphenol (4-CP) as well as measuring the formation of hydroxyl radical spin adducts by EPR spectroscopy was observed. All three methods demonstrated significantly higher activity in comparison with the Degussa P25 photocatalyst. Both methods used for photoactivity tests provided similar results, the activity increased with increasing annealing temperature in order 500°C<Degussa P25<600°C<850–950°C. Results of measurement of formation of OH radicals by EPR also confirmed the unusually high activity of our materials. In comparison with the Degussa P25, the sample annealed at 950°C showed significantly higher production of OH radicals.

Losartan inhibits endothelial-to-mesenchymal transformation in mitral valve endothelial cells by blocking transforming growth factor-β-induced phosphorylation of ERK

Adult cardiac valve endothelial cells (VEC) undergo endothelial to mesenchymal transformation (EndMT) in response to transforming growth factor-β (TGFβ). EndMT has been proposed as a mechanism to replenish interstitial cells that reside within the leaflets and further, as an adaptive response that increases the size of mitral valve leaflets after myocardial infarction. To better understand valvular EndMT, we investigated TGFβ-induced signaling in mitral VEC, and carotid artery endothelial cells (CAEC) as a control. Expression of EndMT target genes α-smooth muscle actin (α-SMA), Snai1, Slug, and MMP-2 were used to monitor EndMT. We show that TGFβ-induced EndMT increases phosphorylation of ERK (p-ERK), and this is blocked by Losartan, an FDA-approved antagonist of the angiotensin II type 1 receptor (AT1), that is known to indirectly inhibit phosphorylation of ERK (p-ERK). Blocking TGF-β-induced p-ERK directly with the MEK1/2 inhibitor RDEA119 was sufficient to prevent EndMT. In mitral VECs, TGFβ had only modest effects on phosphorylation of the canonical TGF-β signaling mediator mothers against decapentaplegic homolog 3 (SMAD3). These results indicate a predominance of the non-canonical p-ERK pathway in TGFβ-mediated EndMT in mitral VECs. AT1 and angiotensin II type 2 (AT2) were detected in mitral VEC, and high concentrations of angiotensin II (AngII) stimulated EndMT, which was blocked by Losartan. The ability of Losartan or MEK1/2 inhibitors to block EndMT suggests these drugs may be useful in manipulating EndMT to prevent excessive growth and fibrosis that occurs in the leaflets after myocardial infarction.

In vitro assessment of a combined radiofrequency ablation and cryo-anchoring catheter for treatment of mitral valve prolapse

Percutaneous approaches to mitral valve repair are an attractive alternative to surgical repair or replacement. Radiofrequency ablation has the potential to approximate surgical leaflet resection by using resistive heating to reduce leaflet size, and cryogenic temperatures on a percutaneous catheter can potentially be used to reversibly adhere to moving mitral valve leaflets for reliable application of radiofrequency energy. We tested a combined cryo-anchoring and radiofrequency ablation catheter using excised porcine mitral valves placed in a left heart flow loop capable of reproducing physiologic pressure and flow waveforms. Transmitral flow and pressure were monitored during the cryo-anchoring procedure and compared to baseline flow conditions, and the extent of radiofrequency energy delivery to the mitral valve was assessed post-treatment. Long term durability of radiofrequency ablation treatment was assessed using statically treated leaflets placed in a stretch bioreactor for four weeks. Transmitral flow and pressure waveforms were largely unaltered during cryo-anchoring. Parameter fitting to mechanical data from leaflets treated with radiofrequency ablation and cryo-anchoring revealed significant mechanical differences from untreated leaflets, demonstrating successful ablation of mitral valves in a hemodynamic environment. Picrosirius red staining showed clear differences in morphology and collagen birefringence between treated and untreated leaflets. The durability study indicated that statically treated leaflets did not significantly change size or mechanics over four weeks. A cryo-anchoring and radiofrequency ablation catheter can adhere to and ablate mitral valve leaflets in a physiologic hemodynamic environment, providing a possible percutaneous alternative to surgical leaflet resection of mitral valve tissue.

Characteristics of Commercial Leaflets Sandwiched in Newspaper (Part 1)- The Size and Printing Types of Leaflets according to Business -

To offer a basic information for the fibers of commercial leaflets, authors examined and analyzed the distribution, size, and printing types of leaflets sandwiched in the newspaper. The number of different leaflet size were almost 30 in two years including B5 (<TEX>$182{\times}257mm$</TEX>), A4 (<TEX>$210{\times}297mm$</TEX>), B4, (<TEX>$257{\times}364mm$</TEX>), A3 (<TEX>$297{\times}420mm$</TEX>), and large flyers such as <TEX>$545{\times}395mm$</TEX>, and <TEX>$790{\times}550mm$</TEX>. The number of different leaflets size were 25 in 2011, which was reduced to 15 in 2012. Both the number and amount of the leaflets were reduced. The high quality leaflets were issued and distributed in the corporate sector and the leaflets issued in other sectors such as shopkeeping, restaurant business, educational institutions were one-sided leaflets printed on single side of the paper. Compared to the previous year, large stores showed the increased number of leaflets but the number of leaflets from restaurant business and educational institutions and building trade were decreased.

Abstract 18388: Novel Study of the Dynamic Changes in Mitral Valve Annular and Leaflet Parameters Under Varying Loading Conditions: A Three-Dimensional Echocardiographic Study

Background: The impact of changing loading conditions on mitral valve (MV) coaptation is controversial. Previous studies assessed the MV at mid or end-systole only, hence MV dynamic changes throughout systole are poorly understood. We used three-dimensional echocardiography (3DE) to explore dynamic changes in MV annular and leaflet parameters during loading stress and inotropy in an animal model. Methods: In open chest model, 8 pigs and 4 dogs were imaged epicardially. 3DE was performed at baseline, with dobutamine infusion, volume infusion and aortic constriction, with a return to baseline hemodynamics between each intervention. The 3DE datasets were analyzed offline using TomTec semi automated MV software. Leaflet (AL) and annular area (AA) were reported as % change from baseline in 5 systolic intervals (1-5; each representing 20% of systole). ANOVA was performed between each intervention and baseline, at the 5 intervals, with Dunnett’s correction. Results: At baseline, MV peak % change of AL and AA occurred during the 4th and 5th intervals respectively. Compared to baseline, dobutamine infusion % change AL was reduced (-5.9% ± 3.8 vs -9.4% ± 6.1, p&lt;0.01) in the 3rd interval, whilst % change AA was reduced throughout systole. With volume loading, % change AL and AA were significantly reduced during intervals 2 to 5. In contrast, with aortic constriction % change AL (-5.9% ± 3.8 vs -2.4% ± 4.8, p&lt;0.05) and %change AA (-1.6% ± 3.8 vs 1.5% ± 5.7, p&lt;0.05) were increased at the 3rd interval (see Figure). Conclusion: Peak MV annular contraction and leaflet apposition occurs in late systole. MV leaflet coaptation area improves in response to increased contractility and pre-load by increasing annular contraction and reducing unopposed leaflet surface. In contrast, increased afterload has the opposite effect on annular and leaflet size, potentially worsening coaptation. The timing of peak annular contraction and leaflet apposition has implications for the design of future MV studies.

Highly photoactive 2D titanium dioxide nanostructures prepared from lyophilized aqueous colloids of peroxo-polytitanic acid

Reaction of hydrogen peroxide with suspensions of thoroughly washed precipitates obtained by neutralization of aqueous solution of titanyl sulfate with aqueous ammonia leads to transparent yellow liquids. In this way prepared colloid solution is a two phase system in which, beyond the water phase, also a liquid hydrated peroxo-polytitanic acid component is present. Freeze drying of this colloid liquid provides a foamy material consisting of thin foils of peroxo-polytitanic acid containing small but not negligible amount of chemically bound ammonia. These foams annealed at temperature above ∼200°C lose water, ammonia and excess of oxygen providing foamy amorphous oxide. At higher temperatures above ∼280°C the amorphous material crystallizes to anatase which transforms at temperatures >850°C to rutile. The size and shape of the initial leaflets forming the foam is preserved up to ∼900°C. Slit shaped porosity is formed during annealing. We observed that the annealed material is highly photoactive, probably owing to highly anisotropic shape of anatase aggregates and their perfect crystallinity.

Three-dimensional changes in mitral valve annulus geometry in organic and functional mitral regurgitation: insights for mitral valve repair

Background: Assessment of changes in mitral valve annulus (MVA) geometry according to mitral regurgitation (MR) etiology is key to select most effective annulus reshape for MV repair. Objectives: Study purpose was to assess MVA changes in organic and functional MR in comparison to normal (N) subjects, by transthoracic 3D echocardiography (3DE). Methods: 30 pts with moderate-severe organic MR (OMR) due to MV prolapse (57±14 yrs, 21 men) and 29 pts with moderate-severe functional MR (FMR) (61±13 yrs, 21 men) were compared to 30 N age-, gender- and body size-matched. Subjects underwent 3D full-volume acquisition of MV. MVA geometry was analyzed at mid-systole with prototype dedicated software (TomTec MV assessment 2.0). Results: Compared to N, both OMR and FMR pts had larger MVA and leaflet size (Table). MVA was more ellipsoidal in OMR pts than in N, due to larger increase in anterolateral-posteromedial (AL-PM) diameter than in antero-posterior (A-P) diameter (sphericity index (SI) correlated inversely to AL-PM diameter: r=-0.45, p=0.013); even though enlarged, FMR had no significant change in sphericity. MVA non-planarity angle and angle between MVA and aortic annulus (Ao-AP) were similar in N vs OMR, but significantly wider in FMR. Tenting height and volume were similar to N in OMR, and significantly higher in FMR. View this table: MVA comparison in N, OMR and FMR Conclusion: Quantitative analysis by 3DE revealed significant differences in MVA between OMR and FMR. While MVA shape is preserved in organic MR, it is severely affected in functional MR.

Abstract 291: Fibulin-1 is Required to Prevent Hypoplastic Semilunar Valve Formation

Fibulin-1 (Fbln1), an extracellular matrix protein, is prominently expressed during outflow tract (OFT) morphogenesis as a component of both the endocardial cushions and OFT valves. Here we sought to investigate the role of Fbln1 in the process of OFT valvulogenesis. Since Fbln1 null mice die perinatally, we first evaluated the effects of Fbln1 deficiency on OFT valve morphology in hearts of embryos at E17.5. Morphometric analysis of 3D reconstructions revealed that in Fbln1 nulls the volume of the anterior leaflet of the pulmonary valve, and the left and non-coronary leaflets of the aortic valve were significantly reduced as compared to wild type (WT) (30-40% reduction; WT n=6, null n=8; p&lt;0.05). The reduced leaflet size correlated with decreased leaflet cell numbers (45%, 30% and 30% respectively; p&lt;0.05). TUNEL and BrdU analysis showed no difference between E17.5 WT and Fbln1 null OFT valves. To determine when abnormalities of OFT valve leaflet cell numbers first occurs, OFT endocardial cushions and prevalvular mesenchyme from E10.5-14.5 null and WT embryos were analyzed. At E10.5, the proximal OFT cushions of Fbln1 nulls were hypercellular (34% increase; p&lt;0.05; n=5 for each genotype) whereas cellularity of distal cushions was not different from WT (p= 0.49). The fact that the ratio of proximal OFT cushion mesenchymal cells to endothelial cells was increased in E10.5 Fbln1 null cushions suggests that alteration in EMT might contribute to the hypercellularity. At E12.5, cellularity of the proximal OFT cushions was observed to decrease by 35% (p&lt;0.05; WT n=4; null n=4). This was accompanied by a 172% increase in apoptosis, with no alteration in the level of proliferation (p&lt;0.05; WT n=3; null n=4). Decreased cellularity and increased apoptosis persisted in the OFT prevalvular mesenchyme of Fbln1 nulls at E14.5 (p&lt;0.05; WT n=2; null n=2). Taken together, Fbln1 specifically regulates cellularization of the proximal endocardial cushion and prevalvular mesenchyme. Mechanistically, Fbln1 may act as a suppressor of cushion EMT and indirectly or directly as an inhibitor of apoptosis.

A quantitative genetic basis for leaf morphology in a set of precisely defined tomato introgression lines.

Introgression lines (ILs), in which genetic material from wild tomato species is introgressed into a domesticated background, have been used extensively in tomato (Solanum lycopersicum) improvement. Here, we genotype an IL population derived from the wild desert tomato Solanum pennellii at ultrahigh density, providing the exact gene content harbored by each line. To take advantage of this information, we determine IL phenotypes for a suite of vegetative traits, ranging from leaf complexity, shape, and size to cellular traits, such as stomatal density and epidermal cell phenotypes. Elliptical Fourier descriptors on leaflet outlines provide a global analysis of highly heritable, intricate aspects of leaf morphology. We also demonstrate constraints between leaflet size and leaf complexity, pavement cell size, and stomatal density and show independent segregation of traits previously assumed to be genetically coregulated. Meta-analysis of previously measured traits in the ILs shows an unexpected relationship between leaf morphology and fruit sugar levels, which RNA-Seq data suggest may be attributable to genetically coregulated changes in fruit morphology or the impact of leaf shape on photosynthesis. Together, our results both improve upon the utility of an important genetic resource and attest to a complex, genetic basis for differences in leaf morphology between natural populations.

Taxonomic notes on the genus Astragalus (Fabaceae) in Iran, with the description of a new species

Astragalus jaldiyanensis is described and illustrated as a new species from Iran. The new species belongs to Astragalus section Hymenostegis. It is closely related to A. assadabadensis, which is a rare species in the subalpine areas of Western Iran. Geographically A. jaldiyanensis is well separated from A. assadabadensis as it occurs in the northwest of Iran. The habit, shape of the calyx and petals are very similar in both species, but the new species differs sufficiently from its relative by having white flowers (vs. yellowish white), leaflets in 8-9 (vs. 4-5) pairs, leaflet size 6-8 x 1.5-2 mm (vs. 15-25 x 2-2.5 mm), keel length 12-13 mm (vs. ca. 16 mm) and peduncle length 7-9 cm (vs. ca. 5 cm). The relationships between the species are discussed. In addition, A. ranjbarii of Astragalus section Dissitiflori is reduced to synonymy of A. ghahremaninejadii.

Excessive respiratory variation in tricuspid regurgitation systolic velocities in patients with severe tricuspid regurgitation

Respiratory changes in tricuspid regurgitation (TR) systolic velocities are occasionally demonstrated by Doppler echocardiography in patients with TR. We tested the hypothesis that excessive respiratory changes in TR velocities are diagnostic of severe TR. The difference between the maximal (expiratory) and minimal (inspiratory) TR systolic velocities during spontaneous respiration was measured by Doppler echocardiography in 68 patients with severe TR and 68 patients with moderate TR. The diagnostic value of the respiratory changes in TR velocity for detecting severe TR was assessed. The respiratory differences in TR velocities were greater in patients with severe TR (0.72 ± 0.30 m/s), compared with patients with moderate TR (0.28 ± 0.18; P < 0.001). Using receiver-operating characteristics analysis, the area under the curve for the respiratory difference in TR velocities for diagnosing severe TR was 0.92 (95% confidence interval: 0.87-0.96; P < 0.001). A difference in TR velocity ≥0.6 m/s had a sensitivity of 66%, specificity of 94%, positive predictive value of 92%, and a negative predictive value of 74% for diagnosing severe TR. Among patients with severe TR, excessive values of TR velocity difference were associated with signs of more severe TR (greater right ventricular size and malcoaptation of the tricuspid valve leaflets). Excessive respiratory changes in Doppler measurements of TR systolic velocities are a specific sign of severe TR.

Development of a Simultaneous Cryo-Anchoring and Radiofrequency Ablation Catheter for Percutaneous Treatment of Mitral Valve Prolapse

Mitral valve prolapse (MVP) is one subtype of mitral valve (MV) disease and is often characterized by enlarged leaflets that are thickened and have disrupted collagen architecture. The increased surface area of myxomatous leaflets with MVP leads to mitral regurgitation, and there is need for percutaneous treatment options that avoid open-chest surgery. Radiofrequency (RF) ablation is one potential therapy in which resistive heating can be used to reduce leaflet size via collagen contracture. One challenge of using RF ablation to percutaneously treat MVP is maintaining contact between the RF ablation catheter tip and a functioning MV leaflet. To meet this challenge, we have developed a RF ablation catheter with a cryogenic anchor for attachment to leaflets in order to apply RF ablation. We demonstrate the effectiveness of the dual-energy catheter in vitro by examining changes in leaflet biaxial compliance, thermal distribution with infrared (IR) imaging, and cryogenic anchor strength. We report that 1250J of RF energy with cryo-anchoring reduced the determinant of the deformation gradient tensor at systolic loading by 23%. IR imaging revealed distinct regions of cryo-anchoring and tissue ablation, demonstrating that the two modalities do not counteract one another. Finally, cryogenic anchor strength to the leaflet was reduced but still robust during the application of RF energy. These results indicate that a catheter having combined RF ablation and cryo-anchoring provides a novel percutaneous treatment strategy for MVP and may also be useful for other percutaneous procedures where anchored ablation would provide more precise spatial control.