Left heart growth and biventricular repair after hybrid palliation

OBJECTIVES: We evaluated the outcomes of biventricular repair after initial hybrid palliation performed in small infants with various forms of left ventricle hypoplasia.METHODS: Between September 2010 and January 2020, a total of 27 patients had biventricular repair after hybrid palliation at a median age of 11 days. Indications for the hybrid approach included growth promotion of the left ventricle outflow tract and/or the aortic valve in 14 patients and that of the left ventricle in 13 patients. Seven reinterventions and 7 reoperations were performed during the interstage period. Significant growth of left ventricle parameters was noted during the median interstage period of 62 days. Sixteen subjects had aortic arch repair, ventricular septal defect closure and relief of subaortic stenosis; 5 patients had the Ross-Konno procedure; 5 patients underwent the Yasui procedure; and 1 patient had unbalanced atrioventricular septal defect and aortic arch repair.RESULTS: Twenty-three patients (85.2%) are alive at a median follow-up of 3.3 years. Two and 3 patients died early and late after achieving biventricular circulation, respectively. There were 22 reinterventions and 15 reoperations after biventricular repair.CONCLUSIONS: Hybrid palliation can stimulate left heart growth in some patients with left ventricle hypoplasia. More patients may eventually achieve biventricular circulation than was initially thought. Additional interventions and operations are foreseeable. Despite ventricular rehabilitation, some patients with borderline left ventricles may develop restrictive physiology.Developmen

Reference values for serum creatinine in children younger than 1 year of age

Reliable reference values of enzymatically assayed serum creatinine categorized in small age intervals are lacking in young children. The aim of this study was to determine reference values for serum creatinine during the first year of life and study the influence of gender, weight and height on these values. Serum creatinine determinations between 2003 and 2008 were retrieved from the hospital database. Strict exclusion criteria ensured the selection of patients without kidney damage. Correlation analysis was performed to evaluate the relation between height, weight and serum creatinine; the Mann–Whitney test was used to evaluate the relation between gender and serum creatinine. A broken stick model was designed to predict normal serum creatinine values. Mean serum creatinine values were found to decrease rapidly from 55 μmol/L on day 1 to 22 μmol/L in the second month of life; they then stabilized at 20 μmol/L until the seventh month, followed by a slight increase. No significant relation was found between serum creatinine and gender, weight and height. We present here reference values of serum creatinine in infants not at risk of decreased renal function. The absence of a relationship with gender, weight and height confirms that height-based equations to estimate glomerular filtration rate are less useful in patients of this age group

Cystatin C: current position and future prospects.

Abstract Cystatin C is a low-molecular-weight protein which has been proposed as a marker of renal function that could replace creatinine. Indeed, the concentration of cystatin C is mainly determined by glomerular filtration and is particularly of interest in clinical settings where the relationship between creatinine production and muscle mass impairs the clinical performance of creatinine. Since the last decade, numerous studies have evaluated its potential use in measuring renal function in various populations. More recently, other potential developments for its clinical use have emerged. This review summarises current knowledge about the physiology of cystatin C and about its use as a renal marker, either alone or in equations developed to estimate the glomerular filtration rate. This paper also reviews recent data about the other applications of cystatin C, particularly in cardiology, oncology and clinical pharmacology. Clin Chem Lab Med 2008;46:1664-86

Long-Term Tubular Dysfunction in Childhood Cancer Survivors; DCCSS-LATER 2 Renal Study

Simple Summary We studied survivors of childhood cancer who received cancer treatment that might affect the kidneys and compared them to controls from the general population. We investigated if there was a difference in the occurrence of tubular dysfunction. The tubules are the part of the kidney responsible for reabsorption of needed substances to the blood and the removal of wastes. After around 25 years since their cancer diagnosis, we found that in general there were no differences between survivors and controls, but survivors more often had losses of small proteins in the urine. Yet, some survivors of childhood cancer were found to have an increased risk of tubular dysfunction. Namely, survivors treated with the chemotherapeutic agents ifosfamide, cisplatin or carboplatin. Therefore, these patients should be monitored during their follow-up. The aim of this nationwide cross-sectional cohort study was to determine the prevalence of and risk factors for tubular dysfunction in childhood cancer survivors (CCS). In the DCCSS-LATER 2 Renal study, 1024 CCS (>= 5 years after diagnosis), aged >= 18 years at study, treated between 1963 and 2001 with potentially nephrotoxic therapy (i.e., nephrectomy, abdominal radiotherapy, total body irradiation, cisplatin, carboplatin, ifosfamide, high-dose cyclophosphamide, or hematopoietic stem cell transplantation) participated, and 500 age- and sex-matched participants from Lifelines acted as controls. Tubular electrolyte loss was defined as low serum levels (magnesium 1.7 mg/mmol was considered as low-molecular weight proteinuria (LMWP). Multivariable risk analyses were performed. After median 25.5 years follow-up, overall prevalence of electrolyte losses in CCS (magnesium 5.6%, potassium 4.5%, phosphate 5.5%) was not higher compared to controls. LMWP was more prevalent (CCS 20.1% versus controls 0.4%). LMWP and magnesium loss were associated with glomerular dysfunction. Ifosfamide was associated with potassium loss, phosphate loss (with cumulative dose > 42 g/m(2)) and LMWP. Cisplatin was associated with magnesium loss and a cumulative dose > 500 mg/m(2) with potassium and phosphate loss. Carboplatin cumulative dose > 2800 mg/m(2) was associated with potassium loss. In conclusion, long-term tubular dysfunction is infrequent. Yet, ifosfamide, cisplatin and carboplatin are risk factors

Plasma Levels of Middle Molecules to Estimate Residual Kidney Function in Haemodialysis without Urine Collection

© 2015 Vilar et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, (http://creativecommons.org/Licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.BACKGROUND: Residual Kidney Function (RKF) is associated with survival benefits in haemodialysis (HD) but is difficult to measure without urine collection. Middle molecules such as Cystatin C and β2-microglobulin accumulate in renal disease and plasma levels have been used to estimate kidney function early in this condition. We investigated their use to estimate RKF in patients on HD. DESIGN: Cystatin C, β2-microglobulin, urea and creatinine levels were studied in patients on incremental high-flux HD or hemodiafiltration(HDF). Over sequential HD sessions, blood was sampled pre- and post-session 1 and pre-session 2, for estimation of these parameters. Urine was collected during the whole interdialytic interval, for estimation of residual GFR (GFRResidual = mean of urea and creatinine clearance). The relationships of plasma Cystatin C and β2-microglobulin levels to GFRResidual and urea clearance were determined. RESULTS: Of the 341 patients studied, 64% had urine output>100 ml/day, 32.6% were on high-flux HD and 67.4% on HDF. Parameters most closely correlated with GFRResidual were 1/β2-micoglobulin (r2 0.67) and 1/Cystatin C (r2 0.50). Both these relationships were weaker at low GFRResidual. The best regression model for GFRResidual, explaining 67% of the variation, was: GFRResidual = 160.3 · (1/β2m) - 4.2. Where β2m is the pre-dialysis β2 microglobulin concentration (mg/L). This model was validated in a separate cohort of 50 patients using Bland-Altman analysis. Areas under the curve in Receiver Operating Characteristic analysis aimed at identifying subjects with urea clearance≥2 ml/min/1.73 m2 was 0.91 for β2-microglobulin and 0.86 for Cystatin C. A plasma β2-microglobulin cut-off of ≤19.2 mg/L allowed identification of patients with urea clearance ≥2 ml/min/1.73 m2 with 90% specificity and 65% sensitivity. CONCLUSION: Plasma pre-dialysis β2-microglobulin levels can provide estimates of RKF which may have clinical utility and appear superior to cystatin C. Use of cut-off levels to identify patients with RKF may provide a simple way to individualise dialysis dose based on RKF.Peer reviewe

Common Genetic Variants Contribute to Risk of Transposition of the Great Arteries

Rationale: Dextro-transposition of the great arteries (D-TGA) is a severe congenital heart defect which affects approximately 1 in 4,000 live births. While there are several reports of D-TGA patients with rare variants in individual genes, the majority of D-TGA cases remain genetically elusive. Familial recurrence patterns and the observation that most cases with D-TGA are sporadic suggest a polygenic inheritance for the disorder, yet this remains unexplored. Objective: We sought to study the role of common single nucleotide polymorphisms (SNPs) in risk for D-TGA. Methods and Results: We conducted a genome-wide association study in an international set of 1,237 patients with D-TGA and identified a genome-wide significant susceptibility locus on chromosome 3p14.3, which was subsequently replicated in an independent case-control set (rs56219800, meta-analysis P=8.6x10-10, OR=0.69 per C allele). SNP-based heritability analysis showed that 25% of variance in susceptibility to D-TGA may be explained by common variants. A genome-wide polygenic risk score derived from the discovery set was significantly associated to D-TGA in the replication set (P=4x10-5). The genome-wide significant locus (3p14.3) co-localizes with a putative regulatory element that interacts with the promoter of WNT5A, which encodes the Wnt Family Member 5A protein known for its role in cardiac development in mice. We show that this element drives reporter gene activity in the developing heart of mice and zebrafish and is bound by the developmental transcription factor TBX20. We further demonstrate that TBX20 attenuates Wnt5a expression levels in the developing mouse heart. Conclusions: This work provides support for a polygenic architecture in D-TGA and identifies a susceptibility locus on chromosome 3p14.3 near WNT5A. Genomic and functional data support a causal role of WNT5A at the locus

Common Genetic Variants Contribute to Risk of Transposition of the Great Arteries

RATIONALE: Dextro-transposition of the great arteries (D-TGA) is a severe congenital heart defect which affects approximately 1 in 4,000 live births. While there are several reports of D-TGA patients with rare variants in individual genes, the majority of D-TGA cases remain genetically elusive. Familial recurrence patterns and the observation that most cases with D-TGA are sporadic suggest a polygenic inheritance for the disorder, yet this remains unexplored. OBJECTIVE: We sought to study the role of common single nucleotide polymorphisms (SNPs) in risk for D-TGA. METHODS AND RESULTS: We conducted a genome-wide association study in an international set of 1,237 patients with D-TGA and identified a genome-wide significant susceptibility locus on chromosome 3p14.3, which was subsequently replicated in an independent case-control set (rs56219800, meta-analysis P=8.6x10-10, OR=0.69 per C allele). SNP-based heritability analysis showed that 25% of variance in susceptibility to D-TGA may be explained by common variants. A genome-wide polygenic risk score derived from the discovery set was significantly associated to D-TGA in the replication set (P=4x10-5). The genome-wide significant locus (3p14.3) co-localizes with a putative regulatory element that interacts with the promoter of WNT5A, which encodes the Wnt Family Member 5A protein known for its role in cardiac development in mice. We show that this element drives reporter gene activity in the developing heart of mice and zebrafish and is bound by the developmental transcription factor TBX20. We further demonstrate that TBX20 attenuates Wnt5a expression levels in the developing mouse heart. CONCLUSIONS: This work provides support for a polygenic architecture in D-TGA and identifies a susceptibility locus on chromosome 3p14.3 near WNT5A. Genomic and functional data support a causal role of WNT5A at the locus

Follow-up observations of GW170817 with the MAGIC telescopes

The discovery of the electromagnetic counterpart AT2017gfo and the GRB 170817A, associated to the binary neutron star merger GW170817, was one of the major advances in the study of gamma-ray bursts (GRBs) and the hallmark of the multi-messenger astronomy with gravitational waves. Another breakthrough in GRB physics is represented by the discovery of the highly energetic, teraelectronvolt (TeV) component in the GRB 190114C, possibly an universal component in all GRBs. This conclusion is also suggested by the hint of TeV emission in the short GRB 160821B and a few more events reported in the literature. The missing observational piece is the joint detection of TeV emission and gravitational waves from a short GRB and its progenitor. MAGIC observed the counterpart AT2017gfo as soon as the visibility conditions allowed it, namely from January to June 2018. These observations correspond to the maximum flux level observed in the radio and X-ray bands. The upper limits derived from TeV observations are compared with the modelling of the late non-thermal emission using the multi-frequency SED

Multiwavelength monitoring of the gravitationally lensed blazar QSO B0218+357 between 2016 and 2020

QSO B0218+357 is currently the only gravitationally lensed source from which very-high-energy (VHE, &100GeV) gamma-ray emission has been detected. We report the multiwavelength monitoring observations of this source performed between 2016 and 2020 in radio interferometry, optical, X-ray and gamma-ray bands. During the monitoring individual flares and hints of enhanced states in optical, X-ray and GeV bands have been observed, and the simultaneous data taken by the MAGIC telescopes allow us to search for the VHE gamma-ray emission associated with these events

MAGIC observations of the nearby short GRB 160821B

Gamma-ray bursts (GRBs), the most luminous explosions in the universe, have at least two types known. One of them, short GRBs, have been thought to originate from binary neutron star (BNS) mergers. The discovery of GW170817 together with a GRB was the first and only direct proof of the hypothesis, and thus the properties of the short GRBs are poorly known yet. Aiming to clarify the underlying physical mechanisms of the short GRBs, we analyzed GRB 160821B, one of the nearest short GRBs known at z=0.162, observed with the MAGIC telescopes. A hint of a gamma-ray signal is found above 0.5 TeV at a significance of >3 sigma during observations from 24 seconds until 4 hours after the burst, as presented in the past. Recently, multi-wavelength data of its afterglow emission revealed a well-sampled kilonova component from a BNS merger, and the importance of GRB 160821B increased concerning GRB-GW studies. Accordingly, we investigated GRB afterglow models again, using the revised multi-wavelength data. We found that the straightforward interpretation with one-zone synchrotron self-Compton model from the external forward shock is in tension with the observed TeV flux, contradicting the suggestion reported previously. In this contribution we discuss the implication from the TeV observation, including alternative scenarios where the TeV emission can be enhanced. We also give a brief outlook of future GeV-TeV observations of short GRBs with imaging atmospheric Cherenkov telescopes, which could shed more light on the GRB-BNS merger relation