Multicenter Long-Term Real World Data on Treatment With Lumasiran in Patients With Primary Hyperoxaluria Type 1

Introduction

The RNA interference (RNAi) medication lumasiran reduces hepatic oxalate production in primary hyperoxaluria type 1 (PH1). Data outside clinical trials are scarce.

Methods

We report on retrospectively and observationally obtained data in 33 patients with PH1 (20 with preserved kidney function, 13 on dialysis) treated with lumasiran for a median of 18 months.

Results

Among those with preserved kidney function, mean urine oxalate (Uox) decreased from 1.88 (baseline) to 0.73 mmol/1.73 m2 per 24h after 3 months, to 0.72 at 12 months, and to 0.65 at 18 months, but differed according to vitamin B6 (VB6) medication. The highest response was at month 4 (0.55, -70.8%). Plasma oxalate (Pox) remained stable over time. Glomerular filtration rate increased significantly by 10.5% at month 18. Nephrolithiasis continued active in 6 patients, nephrocalcinosis ameliorated or progressed in 1 patient each. At last follow-up, Uox remained above 1.5 upper limit of normal (>0.75 mmol/1.73 m2 per 24h) in 6 patients. Urinary glycolate (Uglyc) and plasma glycolate (Pglyc) significantly increased in all, urine citrate decreased, and alkali medication needed adaptation. Among those on dialysis, mean Pox and Pglyc significantly decreased and increased, respectively after monthly dosing (Pox: 78-37.2, Pglyc: 216.4-337.4 μmol/l). At quarterly dosing, neither Pox nor Pglyc were significantly different from baseline levels. An acid state was buffered by an increased dialysis regimen. Systemic oxalosis remained unchanged.

Conclusion

Lumasiran treatment is safe and efficient. Dosage (interval) adjustment necessities need clarification. In dialysis, lack of Pox reduction may relate to dissolving systemic oxalate deposits. Pglyc increment may be a considerable acid load requiring careful consideration, which definitively needs further investigation.

Diagnostic and therapeutic management of vesico-ureteral reflux in pediatric kidney transplantation-Results of an online survey on behalf of the European Society for Paediatric Nephrology

BACKGROUND

Vesico-ureteral reflux (VUR) is considered to be a risk factor for recurrent febrile urinary tract infections and impaired renal transplant survival.

METHODS

An online survey supported by the European Society for Paediatric Nephrology was designed to evaluate current management strategies of VUR in native and transplanted kidneys of recipients aged <18 years.

RESULTS

Seventy-three pediatric transplant centers from 32 countries contributed to the survey. All centers performed urological evaluation prior to pediatric kidney transplantation (KTx) with subsequent interdisciplinary discussion. Screening for VUR in native kidneys (30% in all, 70% in selected patients) led to surgical intervention in 78% (11% in all, 89% in selected patients) with a decided preference of endoscopic intervention over ureterocystoneostomy. Following KTx, continuous antibiotic prophylaxis was applied in 65% of the patients and screening for allograft VUR performed in 93% of selected patients. The main management strategies of symptomatic allograft VUR were continuous antibiotic prophylaxis (83%) and surgical treatment (74%) (endoscopic intervention 55%, redo ureterocystoneostomy 26%).

CONCLUSIONS

This survey demonstrates the high variability in the management of VUR in pediatric KTx recipients, points to knowledge gaps, and might serve as a starting point for improving the care for patients with VUR in native and transplanted kidneys.

Phenotypic Variability in Siblings with Autosomal Recessive Polycystic Kidney Disease

Introduction

Autosomal recessive polycystic kidney disease (ARPKD) is a rare monogenic disorder characterized by early onset fibrocystic hepatorenal changes. Previous reports have documented pronounced phenotypic variability even among siblings in terms of patient survival. The underlying causes for this clinical variability are incompletely understood.

Methods

We present the longitudinal clinical courses of 35 sibling pairs included in the ARPKD registry study ARegPKD, encompassing data on primary manifestation, prenatal and perinatal findings, genetic testing, and family history, including kidney function, liver involvement, and radiological findings.

Results

We identified 70 siblings from 35 families with a median age of 0.7 (interquartile range 0.1–6.0) years at initial diagnosis and a median follow-up time of 3.5 (0.2–6.2) years. Data on PKHD1 variants were available for 37 patients from 21 families. There were 8 patients from 7 families who required kidney replacement therapy (KRT) during follow-up. For 44 patients from 26 families, antihypertensive therapy was documented. Furthermore, 37 patients from 24 families had signs of portal hypertension with 9 patients from 6 families having substantial hepatic complications. Interestingly, pronounced variability in the clinical course of functional kidney disease was documented in only 3 sibling pairs. In 17 of 20 families of our cohort of neonatal survivors, siblings had only minor differences of kidney function at a comparable age.

Conclusion

In patients surviving the neonatal period, our longitudinal follow-up of 70 ARPKD siblings from 35 families revealed comparable clinical courses of kidney and liver diseases in most families. The data suggest a strong impact of the underlying genotype.

Precise variant interpretation, phenotype ascertainment, and genotype-phenotype correlation of children in the EARLY PRO-TECT Alport trial

Early initiation of therapy in patients with Alport syndrome (AS) slows down renal failure by many years. Genotype-phenotype correlations propose that the location and character of the individual's variant correlate with the renal outcome and any extra renal manifestations. In-depth clinical and genetic data of 60/62 children who participated in the EARLY PRO-TECT Alport trial were analyzed. Genetic variants were interpreted according to current guidelines and criteria. Genetically solved patients with X-linked inheritance were then classified according to the severity of their COL4A5 variant into less-severe, intermediate, and severe groups and disease progress was compared. Almost 90% of patients were found to carry (likely) pathogenic variants and classified as genetically solved cases. Patients in the less-severe group demonstrated a borderline significant difference in disease progress compared to those in the severe group (p = 0.05). While having only limited power according to its sample size, an obvious strength is the precise clinical and genetic data of this well ascertained cohort. As in published data differences in clinical progress were shown between patients with COL4A5 less-severe and severe variants. Therefore, clinical and segregational data are important for variant (re)classification. Genetic testing should be mandatory allowing early diagnosis and therapy of AS.

Severe neurological outcomes after very early bilateral nephrectomies in patients with autosomal recessive polycystic kidney disease (ARPKD)

To test the association between bilateral nephrectomies in patients with autosomal recessive polycystic kidney disease (ARPKD) and long-term clinical outcome and to identify risk factors for severe outcomes, a dataset comprising 504 patients from the international registry study ARegPKD was analyzed for characteristics and complications of patients with very early (≤ 3 months; VEBNE) and early (4–15 months; EBNE) bilateral nephrectomies. Patients with very early dialysis (VED, onset ≤ 3 months) without bilateral nephrectomies and patients with total kidney volumes (TKV) comparable to VEBNE infants served as additional control groups. We identified 19 children with VEBNE, 9 with EBNE, 12 with VED and 11 in the TKV control group. VEBNE patients suffered more frequently from severe neurological complications in comparison to all control patients. Very early bilateral nephrectomies and documentation of severe hypotensive episodes were independent risk factors for severe neurological complications. Bilateral nephrectomies within the first 3 months of life are associated with a risk of severe neurological complications later in life. Our data support a very cautious indication of very early bilateral nephrectomies in ARPKD, especially in patients with residual kidney function, and emphasize the importance of avoiding severe hypotensive episodes in this at-risk cohort.

Defibrotide for the Treatment of Pediatric Inflammatory Multisystem Syndrome Temporally Associated With Severe Acute Respiratory Syndrome Coronavirus 2 Infection in 2 Pediatric Patients

The pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 infection is a severe complication of coronavirus disease 2019. Since impaired coagulation and thrombosis/endotheliitis are suspected pathomechanisms, we treated 2 patients with defibrotide, a profibrinolytic, antithrombotic, antiinflammatory oligonucleotide. Symptoms resolved during treatment. Moreover, coagulation parameters indicating hypofibrinolysis and complement activation normalized. The pediatric inflammatory multisystem syndrome temporally associated with severe acute respiratory syndrome coronavirus 2 infection is a severe complication of coronavirus disease 2019. Since impaired coagulation and thrombosis/endotheliitis are suspected pathomechanisms, 2 patients received defibrotide, a profibrinolytic, antithrombotic, antiinflammatory oligonucleotide. Symptoms resolved and hypofibrinolysis/complement activation normalized during treatment.

Heralded Generation of Macroscopic Superposition States in a Spinor Bose-Einstein Condensate

Macroscopic superposition states enable fundamental tests of quantum mechanics and hold a huge potential in metrology, sensing, and other quantum technologies. We propose to generate macroscopic superposition states of a large number of atoms in the ground state of a spin-1 Bose-Einstein condensate. Measuring the number of particles in one mode prepares with large probability highly entangled macroscopic superposition states in the two remaining modes. The macroscopic superposition states are heralded by the measurement outcome. Our protocol is robust under realistic conditions in current experiments, including finite adiabaticity, particle loss, and measurement uncertainty.

Mutations in SLC34A3/NPT2c are associated with kidney stones and nephrocalcinosis

Compound heterozygous and homozygous (comp/hom) mutations in solute carrier family 34, member 3 (SLC34A3), the gene encoding the sodium (Na(+))-dependent phosphate cotransporter 2c (NPT2c), cause hereditary hypophosphatemic rickets with hypercalciuria (HHRH), a disorder characterized by renal phosphate wasting resulting in hypophosphatemia, correspondingly elevated 1,25(OH)2 vitamin D levels, hypercalciuria, and rickets/osteomalacia. Similar, albeit less severe, biochemical changes are observed in heterozygous (het) carriers and indistinguishable from those changes encountered in idiopathic hypercalciuria (IH). Here, we report a review of clinical and laboratory records of 133 individuals from 27 kindreds, including 5 previously unreported HHRH kindreds and two cases with IH, in which known and novel SLC34A3 mutations (c.1357delTTC [p.F453del]; c.G1369A [p.G457S]; c.367delC) were identified. Individuals with mutations affecting both SLC34A3 alleles had a significantly increased risk of kidney stone formation or medullary nephrocalcinosis, namely 46% compared with 6% observed in healthy family members carrying only the wild-type SLC34A3 allele (P=0.005) or 5.64% in the general population (P<0.001). Renal calcifications were also more frequent in het carriers (16%; P=0.003 compared with the general population) and were more likely to occur in comp/hom and het individuals with decreased serum phosphate (odds ratio [OR], 0.75, 95% confidence interval [95% CI], 0.59 to 0.96; P=0.02), decreased tubular reabsorption of phosphate (OR, 0.41; 95% CI, 0.23 to 0.72; P=0.002), and increased serum 1,25(OH)2 vitamin D (OR, 1.22; 95% CI, 1.05 to 1.41; P=0.008). Additional studies are needed to determine whether these biochemical parameters are independent of genotype and can guide therapy to prevent nephrocalcinosis, nephrolithiasis, and potentially, CKD.

Experimental generation of quantum discord via noisy processes

Quantum systems in mixed states can be unentangled and yet still nonclassically correlated. These correlations can be quantified by the quantum discord and might provide a resource for quantum information processing tasks. By precisely controlling the interaction of two ionic qubits with their environment, we investigate the capability of noise to generate discord. Firstly, we show that noise acting on only one quantum system can generate discord between two. States generated in this way are restricted in terms of the rank of their correlation matrix. Secondly, we show that classically correlated noise processes are capable of generating a much broader range of discordant states with correlation matrices of any rank. Our results show that noise processes prevalent in many physical systems can automatically generate nonclassical correlations and highlight fundamental differences between discord and entanglement.

[Clinical relevance and indications for cardiac magnetic resonance imaging 2013: an interdisciplinary expert statement]

During the last years the indications of Cardiac Magnetic Resonance Imaging (CMRI) have been continuously expanded. However, the acceptance of the method by cardiologists and radiologists does not correlate with respect to the diagnostic potential. Several factors, such as expensive equipment, relatively long examination times, high technical know how and lack of remuneration, limit the application of CMRI in everyday clinical practice. Furthermore, doctors tend to apply more conventional, well established diagnostic procedures, the access to the method is still limited and there exist difficulties in the interdisciplinary collaboration. The interdisciplinary Austrian approach to Cardiac Imaging is aimed to improve the aforementioned problems and to support the implementation of CMRI in the diagnostic tree of cardiac diseases thus enabling a cost efficient management of patients in cardiology.

World Health Organization collaborative study to establish a replacement WHO international standard for hepatitis C virus RNA nucleic acid amplification technology assays

BACKGROUND AND OBJECTIVES

A collaborative study was undertaken to establish a replacement for the current (1st) World Health Organization (WHO) hepatitis C virus (HCV) International Standard, 96/790.

MATERIALS AND METHODS

Both the 1(st) International Standard and the replacement standard were prepared from the same starting material by diluting a high titre genotype 1a HCV isolate in pooled, human plasma. The only difference was that each standard was lyophilized in two, separate lyophilisation runs but under the same conditions.

RESULTS

In the study to establish the 1st International Standard, no significant difference in potency was found between the material eventually designated as the 1st International Standard and that now selected as the 2nd International Standard. The present study also showed no significant differences between the materials stored at -20 degrees C and no evidence of degradation over 5 years.

CONCLUSIONS

Material 96/798 was established as the 2nd HCV International Standard and assigned the same unitage as the 1st International Standard, i.e. 10(5) IU/ml (50,000 IU/vial).

A quantitative, internally controlled real-time PCR Assay for the detection of parvovirus B19 DNA

Parvovirus B19 is an erythrovirus causing diverse clinical manifestations ranging from asymptomatic or mild, to more severe outcomes in, for example, immune-compromised patients. B19 is spread primarily via the respiratory route, but it can also be transmitted via blood and blood products. Viral loads in blood or plasma donations amount up to 10(11) genome equivalents/ml. Therefore, screening of plasma for fractionation for the presence of B19 and removal of highly loaded donations is a way to limit considerably the input of B19 into production pools and to improve further the safety of plasma products. An assay for the quantitative detection of B19 DNA, based on real-time PCR using ABI Prism SDS7700 (TaqMan) is described here. This assay allows precise quantitation of viral loads over 7 orders of magnitude. An exogenous internal control (internal quality marker) is included in each individual sample to prevent false negative results. A linearized plasmid is used as an internal quality marker that contains the identical sequence of the B19 target sequence but with an altered probe hybridization site. This allows co-amplification of B19 and internal quality marker and co-detection of FAM (6-carboxyfluorescein) or VIC labeled probes respectively. The assay is validated according to current guidelines (of the International Conference on Harmonization, Paul Ehrlich Institute, and the Council of Europe) and is optimized for high throughput screening.

Tissue-specific expression and cold-induced mRNA levels of uncoupling proteins in the Djungarian hamster

The uncoupling protein 1 (UCP1), a mitochondrial transmembrane protein, is responsible for adaptive thermogenesis in brown adipose tissue (BAT). Two UCP1 homologues, UCP2 and UCP3, were recently discovered, but it is controversial whether they also play a role in energy homeostasis. Djungarian hamster UCPs were found to exhibit high similarity with homologues known in other species. UCP1 mRNA was restricted to BAT, UCP2 mRNA was expressed in multiple tissues, and UCP3 mRNA was detected mainly in BAT and skeletal muscles. We examined the cold-induced regulation of hamster UCP mRNA levels and tested their correlation with serum free fatty acid (FFA) concentrations. In BAT UCP1, UCP2, and UCP3 expression was upregulated in the cold, but the increase and time course of increase differed. In skeletal muscle, UCP2 and UCP3 mRNA levels were not altered. Cold-induced changes of serum FFA levels correlated with the stimulation of UCP1 mRNA in BAT but not with UCP2 and UCP3.

Off-flavor compounds in wine and other food products formed by enzymatical, physical, and chemical degradation of tryptophan and its metabolites

Tryptophan (TRP) and its metabolites are considered as potential precursors of 2-aminoacetophenone (AAP) in different food products causing different off-flavors. AAP is also responsible for the "untypical aging flavor (UTA)" in wine, developing a floor polish-like flavor in white wines within a few months of storage. In this study the formation of AAP was elucidated by GC-MS analysis of volatile components in model systems, grape musts and wines, spiked with TRP and different TRP metabolites like indole-3-acetic acid (IAA) and sulfite. In sulfurized wines and model solutions which were stored at different temperatures (20 degrees C, 45 degrees C) formylaminoacetophenone (FAP) and AAP were formed mainly from IAA with formation rates up to 20 mole%. Minor formation rates of AAP (< 1 mole%) were found in sulfurized solutions of TRP, indole-3-lactic acid, and indole-3-pyruvic acid. The results showed that the formation of AAP in wine can be referred to an oxidative degradation of IAA by superoxide- and hydroxyl-radicals, which can be formed in wine after the sulfuration by cooxidation of sulfite to sulfate. After decarboxylation, pyrrole oxidation, and ring cleavage, FAP was the main volatile compound of the nonenzymatic degradation of IAA by sulfite which was quantitatively hydrolyzed to AAP. The formation of AAP and FAP was significantly lower in white wines than in ethanolic solutions spiked with IAA. However AAP formation rates of up to 5 mole% were still enough for an UTA. Due to the fact that the AAP- and UTA-formation by cooxidation of sulfite and IAA was completely blocked in red wines, it could be deduced that polyphenolic compounds, typical for red wines, have a scavenger effect on the radical oxidation of sulfite. Possibilities for an inhibition of the IAA degradation during winemaking to avoid the UTA in white wines by addition of radical scavengers like grape marc or ascorbic acid are discussed.

Functional dissociation between medial and lateral prefrontal cortical spatiotemporal activation in negative and positive emotions: a combined fMRI/MEG study

The orbitofrontal cortex has been cytoarchitectonically and connectionally subdivided into a medial and a lateral part which are assumed to subserve distinct functions in emotional processing. However the exact spatiotemporal mechanisms of negative and positive emotional processing in medial and lateral orbitofrontal cortex remain unclear. We therefore investigated spatiotemporal orbitofrontal and prefrontal cortical activation patterns during emotional stimulation in a combined fMRI/MEG study. We investigated 10 healthy subjects, 5 women and 5 men. Positive and negative pictures from the International Affective Picture system (IAPS) were used for emotional stimulation, whereas neutral and gray pictures were taken as control conditions. fMRI/MEG measurements covered the whole frontal lobe and a time window between -2000 and +200 ms around motor responses (right index finger extension) associated with each picture. Positively and negatively correlated activities were determined in various prefrontal/frontal cortical regions in fMRI. Isocontour maps and single dipoles in MEG were analyzed in 50 ms time windows ranging from -2000 to +200 ms. Dipoles and fMR images were mapped on three-dimensional anatomical MRI so that anatomical localization of single dipoles and regional fMRI activity could be compared. Both negative and positive emotional conditions differed from non-emotional control conditions by strong orbitofrontal and lateral prefrontal activation as well as by the presence of early magnetic fields (-1700 to +1100 ms). Negative emotional processing was characterized by strong medial orbitofrontal activation and earlier (-1700 ms), stronger and more medially oriented orbitofrontal dipoles. In contrast positive emotional processing showed a rather strong activation in lateral prefrontal cortex with later (-1500 ms), weaker and more laterally oriented orbito and prefrontal dipoles. Negative emotional processing can be characterized by strong and early medial orbitofrontal cortical activation, whereas positive emotional processing showed rather later and weaker activation in lateral orbitofrontal/prefrontal cortex. Such a functional dissociation between medial and lateral orbito-frontal/prefrontal cortex during negative and positive emotional processing lends further support to the assumption of a functional subdivision in the orbitofrontal cortex.

Application of pulsed-Doppler tissue imaging in patients with dual chamber pacing: the importance of conduction time and AV delay on regional left ventricular wall dynamics

Pulsed-Doppler tissue imaging (pDTI) is able to measure myocardial wall velocities (systolic: S; early diastolic: E; late diastolic: A) and their timings. Relationships have been demonstrated between the pre-ejection period and indexes of left ventricular systolic function. This study was designed to examine with pDTI the effects of variations in atrioventricular delay (AVD) (100 ms, 150 ms, 200 ms) on myocardial dynamics and on their timings at the basal interventricular septum (IVS) from an apical approach and at the posterior wall (PW) from the parasternal view. These data were compared with stroke volume measurements recorded from the left ventricular outflow tract. Seventeen patients with dual chamber pacemakers (7 because of complete heart block, 10 with sick sinus syndrome and first-degree AV block) were studied; full atrial and ventricular capture was present at any AVD. These data were also compared with those obtained in 10 age-matched healthy volunteers with comparable heart rates.

RESULTS

Optimal atrial contribution to left ventricular filling and, consequently, best systolic performance were achieved when AVD was programmed such that a mean interval of 77 ms was allowed between the end of the A wave and the beginning of the S wave, similar to what was measured in the healthy control group by pDTI.

CONCLUSION

The noninvasive measurement of timings of the cardiac cycle by pDTI is helpful to determine the optimal AVD in individual patients.

A histone H4 promoter for expression of a phleomycin-resistance gene in Phanerochaete chrysosporium

In this study, two transformation vectors (pMG101 and pMG103) for Phanerochaete chrysosporium were constructed, based on the ble phleomycin-resistance-encoding gene and a homologous histone H4 promoter. Transformation frequencies were 6-10 per micrograms of DNA. Transformed vector DNA could either exist as an unstable replicating plasmid or could be stably integrated. Integrated vector DNA from pMG101, which also contains a histone-encoding H3 gene in the promoter fragment, becomes methylated, resulting in inactivation of ble-dependent resistance. Plasmid pMG103, which lacks the H3, does not show methylation.

[Stereoisomeric aromatic compounds XIX: Asymmetric reduction of 4(5)-oxocarboxylic acids with baker's yeast]

Asymmetric reduction of 4(5)-oxocarboxylic acids (esters) by baker's yeast and cyclization in acidic media yields optically active gamma(delta)-lactones. The evaluation of their chirality and optical purity was carried out by HPLC (HRGC) analysis of the corresponding 1,4(1,5)-diols via diastereomeric esters with (R)-Mosher acid (MTPA) and (S)-O-acyllactic acids respectively. By increasing the 4(5) alkyl side chain 4R(5R) configurated gamma(delta)-lactones with high ee-values are generated.