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Abstract Nitrogen oxide (NOx) pollution is emerging as a primary environmental concern across Europe. While some large European metropolitan areas are already in breach of EU safety limits for NO2, this phenomenon does not seem to be only restricted to large industrialized areas anymore. Many smaller scale populated agglomerations including their surrounding rural areas are seeing frequent NO2 concentration violations. The question of a quantitative understanding of different NOx emission sources is therefore of immanent relevance for climate and air chemistry models as well as air pollution management and health. Here we report simultaneous eddy covariance flux measurements of NOx, CO2, CO and non methane volatile organic compound tracers in a city that might be considered representative for Central Europe and the greater Alpine region. Our data show that NOx fluxes are largely at variance with modelled emission projections, suggesting an appreciable underestimation of the traffic related atmospheric NOx input in Europe, comparable to the weekend-weekday effect, which locally changes ozone production rates by 40%.

Functional near-infrared spectroscopy (fNIRS) allows for a reliable assessment of oxygenated blood flow in relevant brain regions. Recent advancements in immersive virtual reality (VR)-based technology have generated many new possibilities for its application, such as in stroke rehabilitation. In this study, we asked whether there is a difference in oxygenated hemoglobin (HbO 2 ) within brain motor areas during hand/arm movements between immersive and non-immersive VR settings. Ten healthy young participants (24.3 ± 3.7, three females) were tested using a specially developed VR paradigm, called "bus riding", whereby participants used their hand to steer a moving bus. Both immersive and non-immersive conditions stimulated brain regions controlling hand movements, namely motor cortex, but no significant differences in HbO 2 could be found between the two conditions in any of the relevant brain regions. These results are to be interpreted with caution, as only ten participants were included in the study.

The present review aims to explore and discuss recent research relating to the lactate response to resistance training and the potential mechanisms by which lactate may contribute to skeletal muscle hypertrophy or help to prevent muscle atrophy. First, we will discuss foundational information pertaining to lactate including metabolism, measurement, shuttling, and potential (although seemingly elusive) mechanisms for hypertrophy. We will then provide a brief analysis of resistance training protocols and the associated lactate response. Lastly, we will discuss potential shortcomings, resistance training considerations, and future research directions regarding lactate's role as a potential anabolic agent for skeletal muscle hypertrophy.

It has been proposed that superior muscle hypertrophy may be obtained by training muscles predominant in type I fibers with lighter loads and those predominant in type II fibers with heavier loads., Purpose: To evaluate longitudinal changes in muscle strength and hypertrophy of the soleus (a predominantly slow-twitch muscle) and gastrocnemius (muscle with a similar composition of slow and fast-twitch fibers) when subjected to light (20-30 repetition maximum) and heavy (6-10 repetition maximum) load plantarflexion exercise., Methods: The study employed a within-subject design whereby 26 untrained young men had their lower limbs randomized to perform plantarflexion with a low-load (LIGHT) and a high-load (HEAVY) for 8 weeks. Muscle thickness was estimated via B-mode ultrasound and maximal strength was determined by isometric dynamometry., Results: Results showed that changes in muscle thickness were similar for the soleus and the gastrocnemius regardless of the magnitude of load used in training. Furthermore, each of the calf muscles demonstrated robust hypertrophy, with the lateral gastrocnemius showing greater gains compared to the medial gastrocnemius and soleus. Both HEAVY and LIGHT training programs elicited similar hypertrophic increases in the triceps surae. Finally, isometric strength increases were similar between loading conditions., Conclusions: The triceps surae muscles respond robustly to regimented exercise and measures of muscle hypertrophy and isometric strength appear independent of muscle fiber type composition. Moreover, the study provides further evidence that low-load training is a viable strategy to increase hypertrophy in different human muscles, with hypertrophic increases similar to that observed using heavy loads., (© 2020 The Authors. Physiological Reports published by Wiley Periodicals LLC on behalf of The Physiological Society and the American Physiological Society.)

We aimed to investigate the effects of resistance training (RT) combined with no-load isometric actions (iso-holds) during the inter-set recovery period versus RT that involves passive inter-set rest on muscular strength, muscular hypertrophy, and muscular endurance in resistance-trained men. Twenty-seven resistance-trained male volunteers were randomly assigned to either a traditional group (TRAD) that performed a hypertrophy-oriented RT routine with the rest intervals spent passively ( n = 13) or to a group that supplemented traditional RT with iso-holds (ISO) for the working muscle group between each set ( n = 14). Training for both routines consisted of three weekly sessions performed for 8 weeks. Three sets of 8-12 repetitions were performed per exercise. A 2-min rest interval was afforded between sets; the ISO group performed iso-holds for the first 30 s of each rest interval and then recovered for the final 90 s. Maximal strength was assessed using the one repetition maximum (1RM) tests in the leg press and bench press. Upper-body muscle endurance was assessed by performing the bench press to failure at 50% of 1RM. Muscle thickness (MT) of the elbow flexors, elbow extensors, mid-thigh, and lateral thigh was assessed using B-mode ultrasound. Results indicated a favorable effect of ISO on MT in the mid-thigh. Alternatively, there was a possible detrimental effect for ISO on leg press strength. No other notable differences were seen between conditions. In conclusion, the use of inter-set iso-holds may be a time-efficient strategy to enhance development of the quadriceps femoris; conversely, it may be detrimental to maximizing lower body strength., (Copyright © 2020 Schoenfeld, Grgic, Contreras, Delcastillo, Alto, Haun, De Souza and Vigotsky.)

Resistance training volume, determined by the number of sets performed (set-volume) is considered one of the key variables in promoting muscle hypertrophy. To better guide resistance exercise prescription for weekly per-muscle training volume, the purpose of this paper is to provide evidence-based considerations for set-volume ratios between multi-joint (MJ) and single-joint (SJ) exercises so that practitioners can better manage prescription of training volume in program design. We analyzed this topic from three primary areas of focus: (1) biomechanical and physiological factors; (2) acute research; and (3) longitudinal research. From a biomechanical and physiological standpoint, when considering force production of different muscle groups, the moment arm of a given muscle, "motor abundance", the link between biomechanics and exercise-induced fatigue, as well as the amount of time in voluntary muscle activation, a logical rationale can be made for SJ exercises producing greater hypertrophy of the limb muscles than MJ exercises (at least from specific exercises and under certain conditions). This would mean that sets for a MJ exercise should be counted fractionally for select muscles compared to an SJ exercise (i.e., less than a 1:1 ratio) when prescribing set-volumes for given muscles. When considering results from acute studies that measured muscle activation during the performance of SJ and MJ exercises, it seems that MJ exercises are not sufficient to maximize muscle activation of specific muscles. For example, during performance of the leg press and squat, muscle activation of the hamstrings is markedly lower than that of the quadriceps. These results suggest that a 1:1 ratio cannot be assumed. Current longitudinal research comparing the effects of training with MJ vs. SJ or MJ + SJ exercises is limited to the elbow flexors and the evidence is somewhat conflicting. Until more research is conducted to derive stronger conclusions on the topic, we propose the best advice would be to view set-volume prescription on a 1:1 basis, and then use logical rationale and personal expertise to make determinations on program design. Future research should focus on investigating longitudinal hypertrophic changes between MJ and SJ in a variety of populations, particularly resistance-trained individuals, while using site-specific measures of muscle growth to more systematically and precisely compute effective individualized set-volumes.

Nitrogen oxide (NO x ) pollution is emerging as a primary environmental concern across Europe. While some large European metropolitan areas are already in breach of EU safety limits for NO 2 , this phenomenon does not seem to be only restricted to large industrialized areas anymore. Many smaller scale populated agglomerations including their surrounding rural areas are seeing frequent NO 2 concentration violations. The question of a quantitative understanding of different NO x emission sources is therefore of immanent relevance for climate and air chemistry models as well as air pollution management and health. Here we report simultaneous eddy covariance flux measurements of NO x , CO 2 , CO and non methane volatile organic compound tracers in a city that might be considered representative for Central Europe and the greater Alpine region. Our data show that NO x fluxes are largely at variance with modelled emission projections, suggesting an appreciable underestimation of the traffic related atmospheric NO x input in Europe, comparable to the weekend-weekday effect, which locally changes ozone production rates by 40%.

Objectives: In symptomatic patients, performing a primary repair of tetralogy of Fallot (TOF), irrespective of age or placing a shunt, remains controversial. The aim of the study was to analyse the policy of primary correction., Methods: Between May 2005 and May 2012, a total of 87 consecutive patients with TOF, younger than 6 months of age, underwent primary correction. All patients had one source of pulmonary blood flow, with or without a patent ductus arteriosus. The median age at surgery was 106 ± 52.3 days (8-180 days). Twelve patients (13.8%) were newborns. Two groups were analysed: group I, patients <1 month of age; group II, patients between 2-6 months of age., Results: There was no early or late death at 7 years of follow-up. There was no difference in bypass time or hospital stay between the two groups, but the Aristotle comprehensive score (P < 0.0001), ICU stay (P = 0.030) and the length of ventilation (P = 0.014) were significantly different. Freedom from reoperation was 87.3 ± 4.3% and freedom from reintervention was 85.9 ± 4.2% at 7 years, with no difference between the two groups. Neurological development was normal in all patients, but 1 patient in Group II had cerebral seizures and showed developmental delay. Growth was adequate in all patients, except those with additional severe non-cardiac malformations that caused developmental delay. Eighty-five per cent of the patients were without cardiac medication., Conclusions: Even in symptomatic neonates and infants <6 months of age, primary repair of TOF can be performed safely and effectively. One hundred per cent survival at 7 years suggests that early primary repair causes no increase in mortality in the modern era. Shunting is not necessary, even in symptomatic newborns, thus avoiding the risk of shunt-related complications and repeated hospital stays associated with a staged approach.

Background: This study analyzed the long-term outcome after operations for open aortic valvotomy, specifically looking at the preservation of the native aortic valve., Methods: Between 1983 and 2011, 34 neonates with critical aortic stenosis underwent open valvotomy. The mean age at operation was 15 days (range, 1 to 28 days). Follow-up was 100% complete., Results: Three patients died early. The probability of survival was 91.2%, with a mean follow-up of 11 years (range, 10 months to 21 years). Event-free survival was 77%, 68%, 68%, and 57% at 5, 10, 15, and 20 years, respectively, and freedom from aortic valve replacement was 93%, 83%, 68%, and 57%. Tricuspid valve morphology revealed the best outcome, with event-free survival of 90% (p = 0.006) and 100% freedom from aortic valve replacement (p = 0.0012) at 20 years of follow-up. All but 4 patients were in New York Heart Association class I; 77 % of all patients were without medication., Conclusions: In neonates, predictable and consistent long-term results can be accomplished by open valvotomy in any type of valve morphology, even in an asymmetric arrangement. Operative repair not only offers a 90% survival benefit in the long-term but also preserves the native aortic valve in most patients. Clearly superior results were achieved in tricuspid valve morphology, in which there was no need for aortic valve replacement at 20 years of follow-up., (Copyright © 2012 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Objectives: The aim of study was to analyse the mid-term results of the Ross-Konno procedure in infants., Methods: Between 2000 and 2011, 16 infants, including five newborns, with complex left ventricular outflow tract (LVOT) obstruction underwent the Ross-Konno procedure. Twelve patients (75%) required multiple concomitant procedures such as: mitral valve (MV) surgery (four patients), resection of endocardial fibroelastosis (EFE) and myectomy (six patients), closure of ventricular septal defect (four patients) and aortic arch reconstruction (three patients). The median age at operation was 4.2 months (from 6 to 333 days)., Results: There was one late death with a median follow-up of 6.2 years. Actuarial survival is 93.3% at 5 years follow-up (95% confidence interval: 61.2-99.0). Postoperatively, two patients required extracorporeal membrane oxygenation support and one MV replacement. The median length of stay in hospital was 30 days (from 11 to 77 days). At 5 years of follow-up, seven patients had no aortic regurgitation (AR) and nine patients (56%) had trivial AR with no gradient in LVOT. Freedom from mitral regurgitation (MR) ≥ moderate or MV replacement was 70%. MR was associated with either structural abnormalities of MV or with development of EFE. Freedom from redo was 81 and 53% at 1 and 5 years of follow-up. Sixty percent of patients are without medication. All patients are in sinus rhythm., Conclusions: With the technical aspects of this procedure well accomplished, the risk of surgery is minimal and functional outcome is encouraging. However, early postoperative morbidity is significant. At the mid-term follow-up, there was no residual or recurrent outflow tract obstruction and excellent function of the neoaortic valve. A high incidence of MR associated with the development of EFE and structural abnormalities of the MV is worrisome; however, concomitant MV surgery is not associated with increased mortality. In the case of the development of EFE, an early indication for operation might protect MV function. The reoperation rate is high due to early conduit failure.

Objectives: With improved short-term outcomes the right ventricular to pulmonary artery shunt (Sano) has become the preferred pulmonary blood source in the Norwood procedure in many centres. However, most studies analysed consecutive cohorts, with a first modified Blalock-Taussig shunt (BT) followed by the Sano cohort. Besides, neither comprehensive preoperative risk analysis nor outcome beyond 1 year of age was investigated., Methods: This study reviews 109 neonates undergoing the Norwood procedure in the same interval between October 2002 and December 2009. The Sano (38) or BT shunt (71) was assigned according to the surgeon's preference. Two neonates subsequently underwent successful biventricular repair and were excluded. The Aristotle comprehensive score (ACS) was used to evaluate preoperative risk, with high-risk patients (n = 39) classified as having an ACS ≥ 20, and low-risk patients (n = 68) given an ACS <20., Results: Mean Aristotle score at the Norwood operation was 18.8 ± 0.4 and 18.9 ± 0.3 (P = 0.9) in Sano and BT, respectively. Mean follow-up interval was 4.1 ± 2.1 years (range: 1.7-8.9 years). Actuarial survival was similar, stabilizing from the 8th postoperative month onwards at 78.6 ± 4.9% (95% CI: 67.0-86.5%) for Sano and 78.4 ± 6.8% (95% CI: 61.4-88.6%) for BT; P = 0.95. Midterm actuarial survival was higher in low-risk patients, 88.2 ± 3.9% (95% CI: 77.8-93.9%) than in high-risk patients: 61.5 ± 7.8% (95% CI: 44.5-74.7%, P = 0.0003). No survival benefit was detected in low- or high-risk cases for either shunt type. Risk factors for midterm mortality were cardiorespiratory failure requiring ventilation (13/34, P = 0.004), and ACS ≥ 20 (15/39, P = 0.001), but not shunt type (8/37, P = 0.95). Increased number of shunt-related interventions before the Glenn procedure were noted with Sano (32.4 versus 6.5%, P = 0.002)., Conclusions: Preoperative risk factors, regardless of shunt type, influence midterm survival after the Norwood procedure with an excellent outcome in low-risk patients, while high-risk cases still incur a significant mortality. Sano shunt interventions occurred with increased numbers. Although, Sano shunt may be the only feasible option in some instances, given the possible negative effects of ventriculotomy on right ventricle function, the widespread use of Sano shunt should be reconsidered.

Objectives: The aim of this study was to develop a morbidity score based on observed postoperative complications after congenital heart surgery., Methods: Conditions or diseases that impair patients after congenital heart surgery or increase costs of hospital stay were called complications and attributed to scores ranging from 1 (mild) to 4 (severe) points, according to estimated severity or costliness. 'No complication' was assigned 0.5 points. From January to March 2011, scores for each observed 'complication' for every main (primary) surgical procedure were recorded and a morbidity score was calculated. In conformity with the Aristotle score methodology, if the sum of observed complication scores amounted to more than 5 points, a morbidity score of only 5 points was attributed. The estimated morbidity score was compared with the morbidity score attributed by the Aristotle basic complexity (ABC) score., Results: One hundred and thirty-nine primary procedures were carried out. The mean ABC and Aristotle comprehensive complexity scores reached 8.31 ± 2.52 and 9.62 ± 3.47 points, respectively. Two patients died. No complication was detected after 46 procedures. Overall, there were 185 listed 'morbidity' conditions in connection with the other 93 surgical procedures, rendering a total score of 385 points. The most frequent event was 'mechanical ventilation 25-95 h': n = 39. The mean morbidity score was 2.14 ± 1.63. The morbidity scores ranged from 0.5 points (n = 46) to 5 points (n = 23) with a median of 2.0 points. The scores for 11 different procedures that were performed at least five times positively correlated with the corresponding Aristotle morbidity scores: Pearson's coefficient r = 0.75. But the morbidity score for bidirectional cavopulmonary anastomosis (3.14 ± 1.77) was higher than the corresponding Aristotle morbidity score (2.0). It was lower for 'conduit placement, right ventricle to pulmonary artery': 1.08 ± 0.97, versus 2.0, and for arterial switch operation: 2.08 ± 1.11, versus 3.0., Conclusions: The reported morbidity scores need to be tested on larger series and in different institutions. The introduced morbidity score has the potential to quantify postoperative complications accurately. Its estimation over time can facilitate the assessment of quality of congenital heart surgery. It will allow comparison of morbidity outcomes across institutions with different case-mixes.

Objective: Anatomic correction of corrected transposition of the great arteries, utilizing the morphologic left ventricle as a systemic pumping chamber, is considered the preferred method. The purpose of the study was to analyze the intermediate functional outcome following anatomical correction., Methods: Between 1997 and 6/2010, 23 patients with corrected transposition of the great arteries and associated lesions underwent anatomical correction. Seventeen (74%) and six patients (26%) had situs solitus {S,L,L} and situs invs {I,D,D}, respectively. Fifteen patients (65%) had undergone 18 palliations before the corrective operation. The median age at palliation was 0.23 years, with a range of 0.016-8.4 years. A corrective, modified Senning-arterial switch procedure was performed in nine patients, 13 patients underwent a modified Senning-Rastelli procedure, and in one patient a combination of modified Senning and aortic translocation (Bex/Nikaidoh) was used. The median age at the corrective operation was 2 years (from 0.3 to 15.7 years)., Results: There was no mortality or heart transplant within the mean follow-up of 3.4 years. Freedom from reintervention was 77% at 5 years. There were no signs of obstruction of the systemic and pulmonary venous tunnels. The function of both ventricles was normal in all patients, even in the four patients who required retraining of the left ventricle. Mild aortic regurgitation was noticed in three patients. Preoperatively detected significant tricuspid regurgitation either disappeared or became trivial after the operation in all the six patients. All patients except two are in sinus rhythm; one patient is pacemaker-dependent preoperatively and one is pacemaker-dependent postoperatively. There were no clinically apparent neurological problems. All patients, but one, are in the New York Heart Association (NYHA) class I., Conclusions: Anatomic correction of corrected transposition of the great arteries can be performed in selected patients without mortality and with acceptable morbidity. The mid-term functional outcome is excellent, resulting in normal ventricular function, even in retrained left ventricles, and minimal incidence of complete heart block. The long-term function of the aortic valve, intraventricular tunnels, conduits, and ventricles requires close surveillance., (Copyright © 2011 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)

Objectives: Aristotle score methodology defines surgical performance as 'complexity score times hospital survival'. We analysed how this performance evolved over time and in correlation with case volume., Methods: Aristotle basic and comprehensive complexity scores and corresponding basic and comprehensive surgical performances were determined for primary (main) procedures carried out from 2006 to 2009. Surgical case volume performance described as unit performance was estimated as 'surgical performance times the number of primary procedures'., Results: Basic and comprehensive complexity scores for the whole cohort of procedures (n=1828) were 7.74±2.66 and 9.89±3.91, respectively. With an early survival of 97.5% (1783/1828), mean basic and comprehensive surgical performances reached 7.54±2.54 and 9.64±3.81, respectively. Basic surgical performance varied little over the years: 7.46±2.48 in 2006, 7.43±2.58 in 2007, 7.50±2.76 in 2008 and 7.79±2.54 in 2009. Comprehensive surgical performance decreased from 9.56±3.91 (2006) to 9.22±3.94 (2007), and then to 9.13±3.77 (2008), thereafter increasing up to 10.62±3.67 (2009). No significant change of performance was observed for low comprehensive complexity levels 1-3. Variation concerned level 4 (p=0.048) which involved the majority of procedures (746, or 41% of cases) and level 6 (p<0.0001) which included a few cases (20, or 1%), whereas for level 5, statistical significance was almost attained: p=0.079. With a mean annual number of procedures of 457, mean basic and comprehensive unit performance was estimated at 3447±362 and 4405±577, respectively. Basic unit performance increased year to year from 3036 (2006, 100%) to 3254 (2007, 107.2%), then 3720 (2008, 122.5%), up to 3793 (2009, 124.9%). Comprehensive unit performance also increased: from 3891 (2006, 100%) to 4038 (2007, 103.8%), 4528 (2008, 116.4%) and 5172 (2009, 132.9%)., Conclusions: Aristotle scoring of surgical performance allows quality assessment of surgical management of congenital heart disease over time. The newly defined unit performance appears to well reflect the trend of activity and efficiency of a congenital heart surgery department., (Copyright © 2010 European Association for Cardio-Thoracic Surgery. Published by Elsevier B.V. All rights reserved.)

Objective: Neonatal primary repair has progressively become the treatment of choice for truncus arteriosus with encouraging survival. However, use of valved conduits to reconstruct the right ventricular outflow tract (RVOT) inevitably induces reintervention. This study estimates survival and rate of catheter-interventional and surgical reinterventions., Methods: Thirty-five consecutive neonates who underwent truncus repair with 27 homografts and 8 Contegras from 1987 to 2007 were studied. Interrupted aortic arch (IAA) was associated in nine patients. Actuarial survival and freedom from reintervention were evaluated according to Kaplan-Meier method., Results: Five patients died early after repair. Two died late and one death was related to reintervention. Survival was 91.9%+/-5.4% from postoperative month 2 onwards when IAA was not associated and 41.7%+/-17.3% from month 4 in IAA presence. During a median follow-up of 68 months (range 1-180 months), 42 reinterventions (of which 17 reoperations) were performed in 21 patients. Rate of reintervention was 2.6 per early survivor per 10 years. RVOT obstruction constituted the main indication: branch pulmonary arteries often being involved (n=25). Uncommon indication was subaortic stenosis (n=3), aortic arch obstruction (n=2) and truncal valve regurgitation (n=2). At year 10, freedom from first, second and third reintervention was 17.9 %+/-8.1%, 46.1%+/-10.6% and 81.9%+/-9.5%, respectively. Sixteen first conduits were explanted. Freedom from first conduit replacement was 87.5%+/-6.8%, 64.1%+/-10.2% and 39.5%+/-10.7% at year 1, 3 and 5, respectively. Homografts enjoyed higher durability than Contegras., Conclusion: Neonatal repair of truncus arteriosus results in high survival, the only risk being IAA association. The rate of reintervention is heavily influenced by stenosis of branch pulmonary arteries.

We report a case of aortic perforation after transcatheter closure of an atrial septal defect by an Amplatzer septal occluder. During emergency surgery, perforations of the dome of the right atrium and the noncoronary sinus of Valsalva of the aorta were repaired. Atrial septal defect was primarily closed. A short anterosuperior rim should be considered a risk factor for aortic perforation in transcatheter atrial septal defect closure.

Background: The STS-EACTS International Nomenclature for Congenital Heart Surgery (CHS) defines four anatomic subtypes of double outlet right ventricle (DORV) based on the relationship of the ventricular septal defect (VSD) with the great vessels and the presence of right ventricular outflow tract obstruction (RVOTO). We reviewed our experience with DORV patients and two ventricles that underwent repair, applying this nomenclature., Methods: Between January 2000 and January 2005, 50 patients with DORV and two viable ventricles underwent surgical intervention: 44 patients had biventricular repair, 3 had 1.5 ventricular repair, 2 underwent a Fontan, and 1 died prior to corrective surgery. Median age at repair was 9.1 months (range: 4D-4Y). Eighteen patients (36%) were DORV-Fallot (including 5 with AVSD and heterotaxy), 9 (18%) were DORV-TGA (Taussig-Bing), 12 (24%) were DORV-VSD, and 11 (22%) were DORV non-committed VSD. Corrective surgery included 35 repairs with a VSD-aorta baffle+/-RVOTO procedure and 12 arterial switches with a VSD-PA baffle (9 Taussig-Bing and 3 DORV-ncVSD). Associated procedures included 13 VSD enlargements, 8 subaortic resections, 9 arch repairs, 5 AVSD repairs, and 7 others., Results: There were three deaths in the 50 patients studied (overall mortality of 6%). Excluding one patient that died prior to corrective surgery and the two patients palliated with a Fontan procedure, the actual surgical mortality for a corrective repair was 4.3% (2/47 patients). Two surgical deaths occurred following, respectively, one repair of a Taussig-Bing with an interrupted arch and a Swiss cheese VSD and one repair of ncVSD-type with pulmonary atresia that had undergone a previous cavo-pulmonary anastamosis. No late deaths occurred. Two late reoperations included a heart transplant in a DORV-Fallot patient with Swiss cheese VSD and subaortic resection in a DORV-ncVSD patient. Angioplasties were needed for PA stenosis (n=2) and aortic arch obstruction (n=2). Four patients had LV to aorta baffle gradients between 10 and 20 mmHg. All patients were of NYHA class I/II., Conclusions: The STS-EACTS International Nomenclature provides more uniform analysis of outcomes with respect to acceptable surgical risk and mortality. Biventricular repair can be safely achieved on selected DORV, including DORV-ncVSD and DORV with AVSD and heterotaxy lesions traditionally indicated for a single ventricle palliative approach.

The Ross-Konno procedure, applied to neonates with severe left ventricular outflow tract (LVOT) obstruction, offers a satisfactory solution in fully releasing the LVOT gradient, and in replacing the aortic valve with a pulmonary autograft with an excellent growth potential. We reported on three recent neonatal cases.

Objectives: Biventricular repair of double outlet right ventricle non-committed ventricular septal defect (DORVncVSD) is usually achieved by a VSD rerouting to the aorta. This technique can be limited by the presence of tricuspid chordae and by the pulmonary artery to tricuspid valve distance. Furthermore, there is an important risk of late subaortic obstruction related to the long patch required that creates a potential akinetic septal area. Presented here is another technique; by VSD rerouting to the pulmonary infundibulum and arterial switch., Methods: Ten patients, with DORVncVSD, underwent a VSD rerouting to the pulmonary infundibulum followed by arterial switch. Seven had a previous pulmonary artery banding and one a moderate infundibular stenosis. The median age at surgery was 16 months (range 3 weeks to 4.5 years). All patients had a bilateral infundibulum, with a large persistent subaortic conus, D malposition of the aorta, side-by-side vessels and double loop coronary patterns. The VSD was perimembranous with inlet or trabecular extension. Subaortic obstruction was constant. The VSD was severely distant from both the aortic and the pulmonary annulus. The operation was conducted through a combined approach. The VSD was constantly enlarged superiorly. The almost permanent subaortic obstruction was released. The VSD was always found quite close to the pulmonary infundibular ostium. The arterial switch technique was adapted to the complex coronary anatomy., Results: There was one non-cardiac death. At a mean follow-up of 20 months, all nine survivors are in NYHA class I, in sinus rhythm, and have no subaortic gradient greater than 15 mm., Conclusion: This technique of VSD rerouting to the pulmonary artery and arterial switch limits greatly the size of the rerouting patch, respects the tricuspid chordae and is independent of the pulmonary artery-tricuspid valve distance. In this early series of biventricular repair of DORVncVSD, the VSDs were always found close to the pulmonary artery, allowing this new type of repair.

Gene expression in the Caenorhabditis elegans pharynx is regulated in part by organ-specific signals, which in the myo-2 gene target a regulatory sequence called the C sub-element. C sub-element activity requires the organ specification factor PHA-4, a winged-helix transcription factor expressed in all pharyngeal cells. To identify additional factors involved in pharyngeal organogenesis, we performed a yeast one-hybrid screen for C sub-element binding proteins. Here we describe the novel factor PEB-1, which is coexpressed with PHA-4 in many pharyngeal cell types, including muscles, epithelial cells, marginal cells, and glands, but is undetectable in the pharyngeal nervous system. PEB-1 is also detected outside the pharynx in cells surrounding the rectum and vulva, as well as in the germ line. Reduction of peb-1 function using RNAi results in morphological defects in the somatic tissues in which peb-1 is expressed. We have mapped the PEB-1 DNA-binding domain to a 158-residue region, which is unrelated to known DNA-binding proteins but shares some sequence similarity to the Drosophila Mod(mdg4) proteins. PEB-1 specifically recognizes a site in the C subelement that partially overlaps the PHA-4 binding site. Both the PEB-1 and the PHA-4 binding sites are necessary for strong C sub-element enhancer activity in some cells in which these factors are coexpressed. In contrast the PEB-1 site is dispensable for C sub-element activity in pharyngeal neurons. We propose that PEB-1 functions with PHA-4 to activate target gene expression in cells in which they are coexpressed.

Gene expression in the pharyngeal muscles of Caenorhabditis elegans is controlled in part by organ-specific signals, which in the myo-2 gene target a short DNA sequence termed the C subelement. To identify genes contributing to these signals, we performed a yeast one-hybrid screen for cDNAs encoding factors that bind the C subelement. One clone recovered was from daf-3, which encodes a Smad most closely related to vertebrate Smad4. We demonstrated that DAF-3 binds C subelement DNA directly and specifically using gel mobility shift and DNase1 protection assays. Mutation of any base in the sequence GTCTG interfered with binding in the gel mobility shift assay, demonstrating that this pentanucleotide is a core recognition sequence for DAF-3 binding. daf-3 is known to promote formation of dauer larvae and this activity is negatively regulated by TGFbeta-like signaling. To determine how daf-3 affects C subelement enhancer activity in vivo, we examined expression a gfp reporter controlled by a concatenated C subelement oligonucleotide in daf-3 mutants and other mutants affecting the TGFbeta-like signaling pathway controlling dauer formation. Our results demonstrate that wild-type daf-3 can repress C subelement enhancer activity during larval development and, like its dauer-promoting activity, daf-3's repressor activity is negatively regulated by TGFbeta-like signaling. We have examined expression of this gfp reporter in dauer larvae and have observed no daf-3-dependent repression of C activity. These results suggest daf-3 directly regulates pharyngeal gene expression during non-dauer development.

Development of pharyngeal muscle in nematodes and cardiac muscle in vertebrates and insects involves the related homeobox genes ceh-22, nkx2.5, and tinman, respectively. To determine whether the nematode and vertebrate genes perform similar functions, we examined activity of the zebrafish nkx2.5 gene in transgenic Caenorhabditis elegans. Here, we report that ectopic expression of nkx2.5 in C. elegans body wall muscle can directly activate expression of both the endogenous myo-2 gene, a ceh-22 target normally expressed only in pharyngeal muscle, and a synthetic reporter construct controlled by a multimerized CEH-22 binding site. nkx2.5 also efficiently rescues a ceh-22 mutant when expressed in pharyngeal muscle. Together, these results indicate that nkx2.5 and ceh-22 provide a single conserved molecular function. Further, they suggest that an evolutionarily conserved mechanism underlies heart development in vertebrates and insects and pharyngeal development in nematodes.

Pharyngeal muscle development in the nematode Caenorhabditis elegans appears to share similarities with cardiac muscle development in other species. We have previously described CEH-22, an NK-2 class homeodomain transcription factor similar to Drosophila tinman and vertebrate Nkx2-5, which is expressed exclusively in the pharyngeal muscles. In vitro, CEH-22 binds the enhancer from myo-2, a pharyngeal muscle-specific myosin heavy chain gene. In this paper, we examine the role CEH-22 plays in pharyngeal muscle development and gene activation by (a) ectopically expressing ceh-22 in transgenic C. elegans and (b) examining the phenotype of a ceh-22 loss-of-function mutant. These experiments indicate that CEH-22 is an activator of myo-2 expression and that it is required for normal pharyngeal muscle development. However, ceh-22 is necessary for neither formation of the pharyngeal muscles, nor for myo-2 expression. Our data suggest parallel and potentially compensating pathways contribute to pharyngeal muscle differentiation. We also examine the relationship between ceh-22 and the pharyngeal organ-specific differentiation gene pha-1. Mutations in ceh-22 and pha-1 have strongly synergistic effects on pharyngeal muscle gene expression; in addition, a pha-1 mutation enhances the lethal phenotype caused by a mutation in ceh-22. Wild-type pha-1 is not required for the onset of ceh-22 expression but it appears necessary for maintained expression of ceh-22.