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Biennial vegetable crops are challenging to breed due to long breeding cycle times. At the same time, it is important to preserve a strong biennial growth habit, avoiding premature flowering that renders the crop unmarketable. Gene banks carry important genetic variation which may be essential to improve crop resilience, but these collections are underutilized due to lack of characterization for key traits like bolting tendency for biennial vegetable crops. Due to concerns about introducing undesirable traits such as premature flowering into elite germplasm, many accessions may not be considered for other key traits that benefit growers, leaving crops more vulnerable to pests, diseases, and abiotic stresses. In this study, we develop a method for characterizing flowering to identify accessions that are predominantly biennial, which could be incorporated into biennial breeding programs without substantially increasing the risk of annual growth habits. This should increase the use of these accessions if they are also sources of other important traits such as disease resistance. We developed the CarrotOmics flowering habit trait ontology and evaluated flowering habit in the largest (N=695), and most diverse collection of cultivated carrots studied to date. Over 80% of accessions were collected from the Eurasian supercontinent, which includes the primary and secondary centers of carrot diversity. We successfully identified untapped genetic diversity in biennial carrot germplasm (n=197 with 0% plants flowering) and predominantly-biennial germplasm (n=357 with <15% plants flowering). High broad-sense heritability for flowering habit (0.81 < H²< 0.93) indicates a strong genetic component of this trait, suggesting that these carrot accessions should be consistently biennial. Breeders can select biennial plants and eliminate annual plants froma predominantly biennial population. The establishment of the predominantly biennial subcategory nearly doubles the availability of germplasm with commercial potential and accounts for 54% of the germplasm collection we evaluated. This subcollection is a useful source of genetic diversity for breeders. This method could also be applied to other biennial vegetable genetic resources and to introduce higher levels of genetic diversity into commercial cultivars, to reduce crop genetic vulnerability. We encourage breeders and researchers of biennial crops to optimize this strategy for their particular crop. [ABSTRACT FROM AUTHOR]

Carrot (Daucus carota L.) is a high value, nutritious, and colorful crop, but delivering carrots from seed to table can be a struggle for carrot growers. Weed competitive ability is a critical trait for crop success that carrot and its apiaceous relatives often lack owing to their characteristic slow shoot growth and erratic seedling emergence, even among genetically uniform lines. This study is the first field-based, multi-year experiment to evaluate shoot-growth trait variation over a 100-day growing season in a carrot diversity panel (N=695) that includes genetically diverse carrot accessions from the United States Department of Agriculture National Plant Germplasm System. We report phenotypic variability for shoot-growth characteristics, the first broad-sense heritability estimates for seedling emergence (0.68 < H² < 0.80) and earlyseason canopy coverage (0.61 < H² < 0.65), and consistent broad-sense heritability for late-season canopy height (0.76 < H² < 0.82), indicating quantitative inheritance and potential for improvement through plant breeding. Strong correlation between emergence and canopy coverage (0.62 < r < 0.72) suggests that improvement of seedling emergence has great potential to increase yield and weed competitive ability. Accessions with high emergence and vigorous canopy growth are of immediate use to breeders targeting stand establishment, weed-tolerance, or weed-suppressant carrots, which is of particular advantage to the organic carrot production sector, reducing the costs and labor associated with herbicide application and weeding. We developed a standardized vocabulary and protocol to describe shoot-growth and facilitate collaboration and communication across carrot research groups. Our study facilitates identification and utilization of carrot genetic resources, conservation of agrobiodiversity, and development of breeding stocks for weedcompetitive ability, with the long-term goal of delivering improved carrot cultivars to breeders, growers, and consumers. Accession selection can be further optimized for efficient breeding by combining shoot growth data with phenological data in this study's companion paper to identify ideotypes based on global market needs. [ABSTRACT FROM AUTHOR]

Objective: We sought to compare the use of transradial peripheral angiography to guide retrograde revascularization of below-the-knee (BTK) lesions using tibiopedal access (TPA)., Background: Tibiopedal retrograde revascularization of BTK lesions is an emerging technique in peripheral interventions., Methods: We performed an observational cohort study of 194 consecutive adult patients with critical limb ischemia (CLI) who underwent endovascular intervention for BTK diseases using peripheral angiography and primary TPA access with vs without transradial (TR) guidance at 2 centers (New York, USA and Budapest, Hungary). The primary endpoints were procedure success, 30-day major adverse event rate, 30-day access-site complication rate, and 30-day access-site patency rate by ultrasound. Secondary endpoints were periprocedural complications, fluoroscopy time, procedure length, and crossover rate to femoral access., Results: There were 78 patients in the TR-guidance group and 116 patients in the non-TR guidance group. Overall procedure success rates with TR guidance vs without TR guidance were 97% and 98%, respectively. Fluoroscopy times (732.8 ± 615.7 seconds vs 769.8 ± 565.8 seconds; P=NS) and procedure times (46.5 ± 24.4 minutes vs 55.4 ± 12.6 minutes; P=NS) were similar in the TR-guidance group vs the non-TR guidance group, but contrast volumes were higher in the TR-guidance group (100.0 ± 60.1 mL vs 43.8 ± 10.2 mL in the non-TR guidance group; P<.05). There was no difference in 30-day major adverse events, other than higher amputation rate in the TR-guidance group (15.3%), which was attributed to severe baseline complex CLI status in this patient group. There was 1 case of arteriovenous fistula, 1 case of pseudoaneurysm, and 1 case of tibiopedal artery occlusion at 30 days in the group without TR guidance. There were 3 cases (3.8%) of radial artery occlusion in the TR-guidance group., Conclusions: The treatment of CLI with BTK lesions is feasible and safe, with a high procedural success rate and low access-site complication rate using the TPA approach regardless of whether or not TR guidance is utilized.

Background: Atherosclerotic disease of the superficial femoral artery (SFA) is frequently seen and can be treated with percutaneous interventions, traditionally via femoral artery access. There are limited reports of transpedal artery access for peripheral artery interventions, but none to date describing routine primary transpedal artery approach for SFA stenting., Methods: In this preliminary study, we report 4 patients who underwent successful endovascular SFA stenting using a single transpedal artery access via a new ultra-low profile 6 Fr sheath (Glidesheath Slender; Terumo Corporation)., Results: All patients underwent successful SFA stenting without complication. Procedure time varied from 51 to 72 minutes. The mean contrast amount used was 56 mL; mean fluoroscopy time was 21 minutes; mean radiation dose was 91 mGy. At 1-month follow-up, duplex ultrasonography showed that all pedal arteries had remained patent., Conclusions: Transpedal artery approach as a primary approach to SFA stenting appears feasible and safe. Comparative trials with standard percutaneous femoral approach are warranted.

Objectives: To provide new strategies and techniques for the successful recanalization of chronic total occlusions (CTOs) with the sole use of the CrossBoss catheter. In addition, some common CTO scenarios are illustrated in detail., Background: CTOs are one of the most challenging complex coronary lesion subsets to intervene upon. Even with the innovation of specialized catheters, the success rate of antegrade recanalization remains low., Methods: Between June and December 2013, a retrospective analysis of 50 consecutive patients who presented with a planned percutaneous intervention (PCI) of a CTO was performed. In all patients, the CrossBoss catheter was used. No additional reentry devices were necessary. Procedural success was defined as <20% residual stenosis and TIMI-3 distal blood flow of the treated vessel at the end of the procedure., Results: The majority of the patients were male (72%), with an average age of 68 years. Thirty percent of patients presented with prior CTO-PCI failure. The average fluoroscopy time was 45.9 minutes and the average amount of contrast use was 273.8 mL. No patient suffered a coronary perforation from the CrossBoss catheter., Conclusions: With increased experience using the CrossBoss catheter, the antegrade success rate of CTOs can be improved. Some tips include identifying the likely course of the artery with the aid of retrograde injection, proper guidewire selection and manipulation, and redirecting the CrossBoss catheter if there is substantial deviation from the original path.

Objectives: To evaluate the use of extension catheters in transradial intervention of complex coronary lesions., Background: Complex percutaneous coronary intervention (PCI) via transradial approach remains a challenge for many interventionalists, primarily due to the difficulty in obtaining adequate guide catheter support., Methods: A retrospective case series identified 54 patients who presented for PCI of complex coronary lesions. A lesion was defined as complex if it contained severe calcification, proximal tortuosity, chronic total occlusion, or was located distal to a previously implanted stent. After identifying the complex lesions, a conversion to femoral approach was considered, but an attempt via the transradial approach with the use of an extension catheter was chosen as the initial strategy. Specific cases highlighting this approach are illustrated in detail., Results: The average age of the patients was 72 years old, with male predominance (55%). The success rate of completing the transradial intervention with the help of an extension catheter was 96%. Stent delivery failed due to severe tortuosity and calcification in only 2 cases. The coronary artery involved was either the left anterior descending (n = 25), the left circumflex (n = 10), the right coronary artery (n = 14), or a saphenous vein graft (n = 5). There were no coronary dissections evident from use of the extension catheter., Conclusion: In the treatment of complex coronary lesions via the transradial approach, the use of an extension catheter may assist in improving successful intervention and decrease the frequency of crossover to a femoral approach.

Ostial lesions, including aorta-ostial lesions and Medina 001 bifurcation lesions, are known to create difficulty in precise stent placement. There are many techniques used to help in precise ostial stent placement; these include using multiple angiographic views to assist in placement, the use of the Ostial Pro device, the aorta flowing wire technique, Szabo (anchor-wire) techniques, the T-stent and small protrusion (TAP) technique, the cross-over 1-stent technique, and new dedicated ostial stents. In this review, we summarize these different techniques and show that there is no universal technique that allows for perfect ostial stent placement.

Background: The sheathless approach to transradial percutaneous coronary intervention (PCI) has recently gained popularity among interventionalists. However, technical problems and lack of approved equipment in the United States has limited its applicability. We describe a new approach, balloon-assisted sheathless transradial intervention (BASTI) that can ease the use of 5 Fr sheathless guiding catheters and decrease complication rates., Methods: Twenty-seven consecutive patients undergoing staged elective PCI were enrolled. Radial artery access was obtained using the BASTI method - inflation of a compliant coronary balloon at the tip of the guiding catheter was used to ease the transition of the catheter into the skin. The guidewire and coronary balloon were reused during the PCI. Each of the patients had clinical postprocedure follow-up at radial compression device release, and at 1 day, 7 days, and 30 days. Major adverse cardiac events and access-site complications, including radial artery occlusion (RAO), were documented., Results: In this consecutive series, we successfully attempted (27/27) BASTIs. There were no difficulties in obtaining radial artery access with the 5 Fr sheathless guiding catheter. Two patients had balloon rupture during initial radial artery access, but were successfully re-attempted with a higher balloon inflation pressure. All patients then underwent successful coronary intervention. There were no adverse events or procedure-related complications at any time period during follow-up., Conclusion: BASTI is a feasible alternative to conventional techniques and may reduce vascular access-site complications and patient morbidity in a cost-effective manner.

Although the provisional stenting technique to treat coronary bifurcation lesions is the preferred method, many bifurcation lesions still require a two-stent technique to optimize the result and clinical outcome. This manuscript summarizes the tips and tricks of bifurcation stenting with cases illustrations. As interventionists are encountering more complex and difficult cases, one may find the tips and tricks in this manuscript helpful in daily practice.

Radial artery pseudoaneurysm is an extremely rare complication associated with transradial catheterization. We report 2 cases of pseudoaneurysm of the radial artery that were successfully treated using the Terumo TR band. We believe that the safety, efficiency, speed and minimal invasiveness of this method make it feasible for use as a treatment for peripheral pseudoaneurysm in such patients.