CIAO1 and MMS19 deficiency: A lethal neurodegenerative phenotype caused by cytosolic Fe-S cluster protein assembly disorders.

PURPOSE: The functionality of many cellular proteins depends on cofactors; yet, they have only been implicated in a minority of Mendelian diseases. Here, we describe the first 2 inherited disorders of the cytosolic iron-sulfur protein assembly system. METHODS: Genetic testing via genome sequencing was applied to identify the underlying disease cause in 3 patients with microcephaly, congenital brain malformations, progressive developmental and neurologic impairments, recurrent infections, and a fatal outcome. Studies in patient-derived skin fibroblasts and zebrafish models were performed to investigate the biochemical and cellular consequences. RESULTS: Metabolic analysis showed elevated uracil and thymine levels in body fluids but no pathogenic variants in DPYD, encoding dihydropyrimidine dehydrogenase. Genome sequencing identified compound heterozygosity in 2 patients for missense variants in CIAO1, encoding cytosolic iron-sulfur assembly component 1, and homozygosity for an in-frame 3-nucleotide deletion in MMS19, encoding the MMS19 homolog, cytosolic iron-sulfur assembly component, in the third patient. Profound alterations in the proteome, metabolome, and lipidome were observed in patient-derived fibroblasts. We confirmed the detrimental effect of deficiencies in CIAO1 and MMS19 in zebrafish models. CONCLUSION: A general failure of cytosolic and nuclear iron-sulfur protein maturation caused pleiotropic effects. The critical function of the cytosolic iron-sulfur protein assembly machinery for antiviral host defense may well explain the recurrent severe infections occurring in our patients.

Glutaminase Deficiency Caused by Short Tandem Repeat Expansion in GLS.

We report an inborn error of metabolism caused by an expansion of a GCA-repeat tract in the 5' untranslated region of the gene encoding glutaminase (GLS) that was identified through detailed clinical and biochemical phenotyping, combined with whole-genome sequencing. The expansion was observed in three unrelated patients who presented with an early-onset delay in overall development, progressive ataxia, and elevated levels of glutamine. In addition to ataxia, one patient also showed cerebellar atrophy. The expansion was associated with a relative deficiency of GLS messenger RNA transcribed from the expanded allele, which probably resulted from repeat-mediated chromatin changes upstream of the GLS repeat. Our discovery underscores the importance of careful examination of regions of the genome that are typically excluded from or poorly captured by exome sequencing.

ß-Ureidopropionase deficiency due to novel and rare UPB1 mutations affecting pre-mRNA splicing and protein structural integrity and catalytic activity.

ß-Ureidopropionase is the third enzyme of the pyrimidine degradation pathway and catalyses the conversion of N-carbamyl-ß-alanine and N-carbamyl-ß-aminoisobutyric acid to ß-alanine and ß-aminoisobutyric acid, ammonia and CO2. To date, only a limited number of genetically confirmed patients with a complete ß-ureidopropionase deficiency have been reported. Here, we report on the clinical, biochemical and molecular findings of 10 newly identified ß-ureidopropionase deficient individuals. Patients presented mainly with neurological abnormalities and markedly elevated levels of N-carbamyl-ß-alanine and N-carbamyl-ß-aminoisobutyric acid in urine. Analysis of UPB1, encoding ß-ureidopropionase, showed 5 novel missense variants and two novel splice-site variants. Functional expression of the UPB1 variants in mammalian cells showed that recombinant ß-ureidopropionase carrying the p.Ala120Ser, p.Thr129Met, p.Ser300Leu and p.Asn345Ile variant yielded no or significantly decreased ß-ureidopropionase activity. Analysis of the crystal structure of human ß-ureidopropionase indicated that the point mutations affect substrate binding or prevent the proper subunit association to larger oligomers and thus a fully functional ß-ureidopropionase. A minigene approach showed that the intronic variants c.[364 + 6 T > G] and c.[916 + 1_916 + 2dup] led to skipping of exon 3 and 8, respectively, in the process of UPB1 pre-mRNA splicing. The c.[899C > T] (p.Ser300Leu) variant was identified in two unrelated Swedish ß-ureidopropionase patients, indicating that ß-ureidopropionase deficiency may be more common than anticipated.

Children with atopic dermatitis show increased activity of ß-glucocerebrosidase and stratum corneum levels of glucosylcholesterol that are strongly related to the local cytokine milieu.

BACKGROUND: Atopic dermatitis (AD) is characterized by immune dysregulations and an impaired skin barrier, including abnormalities in lipid organization. In the stratum corneum (SC), ß-glucocerebrosidase (GBA) mediates transformation of glucosylceramide (GlcCER) into ceramide (CER) and cholesterol into glucosylcholesterol (GlcChol). Alteration in GBA activity might contribute to skin barrier defects in AD. OBJECTIVES: To investigate GBA activity in the SC of children with AD before and after topical corticosteroid therapy and to compare it with healthy controls; to determine SC levels of GlcCER- and CER-containing hydroxysphingosine base (GlcCER[H] and CER[H], respectively) and GlcChol; and to relate them to disease severity, skin barrier function and the local cytokine milieu. METHODS: Lipid markers and cytokines of innate, T helper 1 and T helper 2 immunity were determined in SC collected from healthy children and from clinically unaffected skin of children with AD, before and after 6 weeks of therapy with topical corticosteroids. AD severity was assessed by Scoring Atopic Dermatitis and skin barrier function by transepidermal water loss (TEWL). RESULTS: Baseline GBA activity and GlcChol levels were increased in children with AD but declined after therapy. CER[H] levels and the CER[H] to GlcCER[H] ratio were increased in AD. GBA activity and GlcChol correlated with TEWL and levels of multiple cytokines, especially interleukin-1α and interleukin-18. GlcChol was strongly associated with disease severity. CONCLUSIONS: We show increased GBA activity and levels of GlcChol in AD. Our data suggest an important role of inflammation in disturbed lipid processing. GBA activity or GlcChol might be useful biomarkers in the monitoring of therapeutic responses in AD. What is already known about this topic? Patients with atopic dermatitis (AD) have a reduced skin barrier, mainly caused by altered lipid organization. The mechanisms underlying these lipid anomalies are not fully understood but likely reflect both genetic abnormalities in AD skin and the local cutaneous inflammatory environment. What does this study add? We show increased activity of the ceramide-generating enzyme ß-glucocerebrosidase in AD. Activity of this enzyme was correlated with the local cytokine milieu and declined after local corticosteroid therapy. We show that glucosylcholesterol levels in the stratum corneum are increased in AD. The function of glucosylcholesterol and the physiological consequences of increased levels are not clear yet; however, its levels were strongly correlated with skin barrier function: high transepidermal water loss strongly correlated with high levels of glucosylcholesterol. What is the translational message? Correction of cutaneous inflammation largely restores alterations in lipid metabolism in the stratum corneum of infants with AD.

Effects of psychological treatment of mental health problems in pregnant women to protect their offspring: randomised controlled trial.

BACKGROUND: Perinatal depression and anxiety are associated with unfavourable child outcomes. AIMS: To assess among women with antenatal depression or anxiety the effectiveness of prenatally initiated cognitive-behavioural therapy (CBT) on mother and child compared with care as usual (CAU). Trial registration: Netherlands Trial Register number NTR2242. METHOD: Pregnant women (n = 282) who screened positive for symptoms of depression and/or anxiety were randomised to either CBT (n = 140) or CAU (n = 142). The primary outcome was child behavioural and emotional problems at age 18 months, assessed using the Child Behavior Checklist (CBCL). Secondary outcomes were maternal symptoms during and up to 18 months after pregnancy, neonatal outcomes, mother-infant bonding and child cognitive and motor development at age 18 months. RESULTS: In total, 94 (67%) women in the CBT group and 98 (69%) in the CAU group completed the study. The mean CBCL Total Problems score was non-significantly higher in the CBT group than in the CAU group (mean difference: 1.38 (95% CI -1.82 to 4.57); t = 0.85, P = 0.399). No effects on secondary outcomes were observed except for depression and anxiety, which were higher in the CBT group than in the CAU group at mid-pregnancy. A post hoc analysis of the 98 women with anxiety disorders showed lower infant gestational age at delivery in the CBT than in the CAU group. CONCLUSIONS: Prenatally initiated CBT did not improve maternal symptoms or child outcomes among non-help-seeking women with antenatal depression or anxiety. Our findings are not in line with present recommendations for universal screening and treatment for antenatal depression or anxiety, and future work may include the relevance of baseline help-seeking.

Genome sequencing reveals a novel genetic mechanism underlying dihydropyrimidine dehydrogenase deficiency: A novel missense variant c.1700G>A and a large intragenic inversion in DPYD spanning intron 8 to intron 12.

Dihydropyrimidine dehydrogenase (DPD) deficiency is associated with a variable clinical presentation. A family with three DPD-deficient patients presented with unusual clinical phenotypes including pregnancy-induced symptoms, transient visual impairment, severe developmental delay, cortical blindness, and delayed myelination in the brain. DPYD Sanger sequencing showed heterozygosity for the c.1905+1G>A mutation and a novel missense variant c.1700G>A (p.G567E). The recombinantly expressed p.G567E DPD variant showed increased temperature lability probably caused by structural rearrangements within the DPD protein. Genome sequencing of the affected son established compound heterozygosity for the c.1700G>A and an imperfect 115,731 bp inversion with breakpoints at chr1: 98,113,121 (intron 8) and chr1: 97,997,390 (intron 12) of the DPYD associated with a 4 bp deletion (chr1: 97,997,386_97,997,389del). Whole exome and mitochondrial DNA analyses for the mother and daughter did not reveal additional mutated genes of significance. Thus, an inversion in DPYD should be considered in patients with an inconclusive genotype or unusual clinical phenotype.

Capecitabine-based treatment of a patient with a novel DPYD genotype and complete dihydropyrimidine dehydrogenase deficiency.

Fluoropyrimidines are frequently used anti-cancer drugs. It is known that patients with reduced activity of dihydropyrimidine dehydrogenase (DPD), the key metabolic enzyme in fluoropyrimidine inactivation, are at increased risk of developing severe fluoropyrimidine-related toxicity. Upfront screening for DPD deficiency and dose reduction in patients with partial DPD deficiency is recommended and improves patient safety. For patients with complete DPD deficiency, fluoropyrimidine-treatment has generally been discouraged. During routine pretreatment screening, we identified a 59-year-old patient with a sigmoid adenocarcinoma who proved to have a complete DPD deficiency. Genetic analyses showed that this complete absence of DPD activity was likely to be caused by a novel DPYD genotype, consisting of a combination of amplification of exons 17 and 18 of DPYD and heterozygosity for DPYD*2A. Despite absence of DPD activity, the patient was treated with capecitabine-based chemotherapy, but capecitabine dose was drastically reduced to 150 mg once every 5 days (0.8% of original dose). Pharmacokinetic analyses showed that the area under the concentration-time curve (AUC) and half-life of 5-fluorouracil were respectively tenfold and fourfold higher than control values of patients receiving capecitabine 850 mg/m2 . When extrapolating from the dosing schedule of once every 5 days to twice daily, the AUC of 5-fluorouracil was comparable to controls. Treatment was tolerated well for eight cycles by the patient without occurrence of capecitabine-related toxicity. This case report demonstrates that a more comprehensive genotyping and phenotyping approach, combined with pharmacokinetically-guided dose administration, enables save fluoropyrimidine-treatment with adequate drug exposure in completely DPD deficient patients.

Respiratory Health in Adolescents Born Moderately-Late Preterm in a Community-Based Cohort.

OBJECTIVES: To determine the long-term effects of moderately-late preterm (MLP) birth on respiratory and allergic symptoms, lung function, and exercise capacity in adolescence. STUDY DESIGN: Outcome variables in this prospective cohort were prevalence of symptoms determined by International Study of Asthma and Allergies in Childhood questionnaires, lung function, and exercise measures. RESULTS: Response rate was 47% and did not vary importantly by background characteristics. In total, 71 children (aged 13-14 years) participated in the measurements, 37 born MLP and 34 born full term. Both groups were comparable in height, weight, and exercise activities but differed in gestational age (MLP 34 ± 1 weeks, full term 39 ± 0.9 weeks) and birth weight (MLP 2442 ± 539 g, full term 3693 ± 393 g). Adolescents born MLP reported more (dry) cough (MLP 25% vs those born full term 3%, P = .016) and hay fever (MLP 34% vs those born full term 9%, P = .015). Adolescents born MLP did not report more wheeze, dyspnea, asthma, and eczema. Most lung function measurements were within the normal range for both groups, except peak expiratory flow (MLP 86% of predicted vs those born full term 93%, P = .05) and maximum expiratory flow when 75% of the forced vital capacity has been exhaled (MLP 86% predicted vs those born full term 96% predicted, P = .06), which were at the lower limit of normal. We observed no differences between the groups in exercise parameters. CONCLUSION: Moderately late preterm birth has little effect on respiratory health in adolescence. Adolescents born MLP report few symptoms, have only slightly more lung function abnormalities than those born full term, and do not differ in the maximal exercise test and in physical activity level. TRIAL REGISTRATION: ISRCTN 80622320.

Phenotypic and clinical implications of variants in the dihydropyrimidine dehydrogenase gene.

Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of the pyrimidine bases uracil, thymine and the antineoplastic agent 5-fluorouracil. Genetic variations in the gene encoding DPD (DPYD) have emerged as predictive risk alleles for 5FU-associated toxicity. Here we report an in-depth analysis of genetic variants in DPYD and their consequences for DPD activity and pyrimidine metabolites in 100 Dutch healthy volunteers. 34 SNPs were detected in DPYD and 15 SNPs were associated with altered plasma concentrations of pyrimidine metabolites. DPD activity was significantly associated with the plasma concentrations of uracil, the presence of a specific DPYD mutation (c.1905+1G>A) and the combined presence of three risk variants in DPYD (c.1905+1G>A, c.1129-5923C>G, c.2846A>T), but not with an altered uracil/dihydrouracil (U/UH2) ratio. Various haplotypes were associated with different DPD activities (haplotype D3, a decreased DPD activity; haplotype F2, an increased DPD activity). Functional analysis of eight recombinant mutant DPD enzymes showed a reduced DPD activity, ranging from 35% to 84% of the wild-type enzyme. Analysis of a DPD homology model indicated that the structural effect of the novel p.G401R mutation is most likely minor. The clinical relevance of the p.D949V mutation was demonstrated in a cancer patient heterozygous for the c.2846A>T mutation and a novel nonsense mutation c.1681C>T (p.R561X), experiencing severe grade IV toxicity. Our studies showed that the endogenous levels of uracil and the U/UH2 ratio are poor predictors of an impaired DPD activity. Loading studies with uracil to identify patients with a DPD deficiency warrants further investigation.

Severe fluoropyrimidine toxicity due to novel and rare DPYD missense mutations, deletion and genomic amplification affecting DPD activity and mRNA splicing.

Dihydropyrimidine dehydrogenase (DPD) is the initial and rate-limiting enzyme in the catabolism of 5-fluorouracil (5FU). Genetic variations in DPD have emerged as predictive risk factors for severe fluoropyrimidine toxicity. Here, we report novel and rare genetic variants underlying DPD deficiency in 9 cancer patients presenting with severe fluoropyrimidine-associated toxicity. All patients possessed a strongly reduced DPD activity, ranging from 9 to 53% of controls. Analysis of the DPD gene (DPYD) showed the presence of 21 variable sites including 4 novel and 4 very rare aberrations: 3 missense mutations, 2 splice-site mutations, 1 intronic mutation, a deletion of 21 nucleotides and a genomic amplification of exons 9-12. Two novel/rare variants (c.2843T>C, c.321+1G>A) were present in multiple, unrelated patients. Functional analysis of recombinantly-expressed DPD mutants carrying the p.I948T and p.G284V mutation showed residual DPD activities of 30% and 0.5%, respectively. Analysis of a DPD homology model indicated that the p.I948T and p.G284V mutations may affect electron transfer and the binding of FAD, respectively. cDNA analysis showed that the c.321+1G>A mutation in DPYD leads to skipping of exon 4 immediately upstream of the mutated splice-donor site in the process of DPD pre-mRNA splicing. A lethal toxicity in two DPD patients suggests that fluoropyrimidines combined with other therapies such as radiotherapy might be particularly toxic for DPD deficient patients. Our study advocates a more comprehensive genotyping approach combined with phenotyping strategies for upfront screening for DPD deficiency to ensure the safe administration of fluoropyrimidines.

Dihydropyrimidinase deficiency in four East Asian patients due to novel and rare DPYS mutations affecting protein structural integrity and catalytic activity.

Dihydropyrimidinase (DHP) is the second enzyme of the pyrimidine degradation pathway and catalyzes the ring opening of 5,6-dihydrouracil and 5,6-dihydrothymine. To date, only 31 genetically confirmed patients with a DHP deficiency have been reported and the clinical, biochemical and genetic spectrum of DHP deficient patients is, therefore, still largely unknown. Here, we show that 4 newly identified DHP deficient patients presented with strongly elevated levels of 5,6-dihydrouracil and 5,6-dihydrothymine in urine and a highly variable clinical presentation, ranging from asymptomatic to infantile spasm and reduced white matter and brain atrophy. Analysis of the DHP gene (DPYS) showed the presence of 8 variants including 4 novel/rare missense variants and one novel deletion. Functional analysis of recombinantly expressed DHP mutants carrying the p.M250I, p.H295R, p.Q334R, p.T418I and the p.R490H variant showed residual DHP activities of 2.0%, 9.8%, 9.7%, 64% and 0.3%, respectively. The crystal structure of human DHP indicated that all point mutations were likely to cause rearrangements of loops shaping the active site, primarily affecting substrate binding and stability of the enzyme. The observation that the identified mutations were more prevalent in East Asians and the Japanese population indicates that DHP deficiency may be more common than anticipated in these ethnic groups.

Evaluation of an oral uracil loading test to identify DPD-deficient patients using a limited sampling strategy.

AIM: Dihydropyrimidine dehydrogenase (DPD) deficiency can lead to severe toxicity following 5-fluorouracil (5FU) or capecitabine (CAP) treatment. Uracil (U) can be used as a probe to determine systemic DPD activity. The present study was performed to assess the sensitivity and specificity of a U loading dose for detecting DPD deficiency. METHODS: Cancer patients with Common Toxicity Score (CTC) grade III or IV toxicity after the first or second cycle of 5-FU or CAP treatment were asked to participate. Based on DPD activity in PBMCs, patients were divided into two groups: DPD activity in peripheral blood mononuclear cells (PBMCs) <5 nmol mg(-1) *h(-1) (deficient group) and ≥ 5 nmol mg(-1) *h(-1) . U 500 mg m(-2) was administered orally and plasma concentrations of U and dihydrouracil (DHU) were determined. In the deficient group, polymerase chain reaction amplification of all 23 coding exons and flanking intronic regions of DPYD was performed. A U pharmacokinetic model was developed and used to determine the maximum enzymatic conversion capacity (Vmax ) of the DPD enzyme for each patient. The sensitivity and specificity of Vmax, U concentration and the U/DHU concentration ratio were determined. RESULTS: A total of 47 patients were included (19 DPD deficient, 28 DPD normal). Of the pharmacokinetic parameters investigated, a sensitivity and specificity of 80% and 98%, respectively, was obtained for the U/DHU ratio at t = 120 min. CONCLUSIONS: The high sensitivity of the U/DHU ratio at t = 120 min for detecting DPD deficiency, as defined by DPD activity in PBMCs, showed that the oral U loading dose can effectively identify patients with reduced DPD activity.

Altered Pre-mRNA Splicing Caused by a Novel Intronic Mutation c.1443+5G>A in the Dihydropyrimidinase (DPYS) Gene.

Dihydropyrimidinase (DHP) deficiency is an autosomal recessive disease caused by mutations in the DPYS gene. Patients present with highly elevated levels of dihydrouracil and dihydrothymine in their urine, blood and cerebrospinal fluid. The analysis of the effect of mutations in DPYS on pre-mRNA splicing is hampered by the fact that DHP is primarily expressed in liver and kidney cells. The minigene approach can detect mRNA splicing aberrations using cells that do not express the endogenous mRNA. We have used a minigene-based approach to analyze the effects of a presumptive pre-mRNA splicing mutation in two newly identified Chinese pediatric patients with DHP deficiency. Mutation analysis of DPYS showed that both patients were compound heterozygous for a novel intronic mutation c.1443+5G>A in intron 8 and a previously described missense mutation c.1001A>G (p.Q334R) in exon 6. Wild-type and the mutated minigene constructs, containing exons 7, 8 and 9 of DPYS, yielded different splicing products after expression in HEK293 cells. The c.1443+5G>A mutation resulted in altered pre-mRNA splicing of the DPYS minigene construct with full skipping of exon 8. Analysis of the DHP crystal structure showed that the deletion of exon 8 severely affects folding, stability and homooligomerization of the enzyme as well as disruption of the catalytic site. Thus, the analysis suggests that the c.1443+5G>A mutation results in aberrant splicing of the pre-mRNA encoding DHP, underlying the DHP deficiency in two unrelated Chinese patients.

Clinical, biochemical and molecular analysis of 13 Japanese patients with ß-ureidopropionase deficiency demonstrates high prevalence of the c.977G > A (p.R326Q) mutation [corrected].

ß-ureidopropionase (ßUP) deficiency is an autosomal recessive disease characterized by N-carbamyl-ß-amino aciduria. To date, only 16 genetically confirmed patients with ßUP deficiency have been reported. Here, we report on the clinical, biochemical and molecular findings of 13 Japanese ßUP deficient patients. In this group of patients, three novel missense mutations (p.G31S, p.E271K, and p.I286T) and a recently described mutation (p.R326Q) were identified. The p.R326Q mutation was detected in all 13 patients with eight patients being homozygous for this mutation. Screening for the p.R326Q mutation in 110 Japanese individuals showed an allele frequency of 0.9 %. Transient expression of mutant ßUP enzymes in HEK293 cells showed that the p.E271K and p.R326Q mutations cause profound decreases in activity (≤ 1.3 %). Conversely, ßUP enzymes containing the p.G31S and p.I286T mutations possess residual activities of 50 and 70 %, respectively, suggesting we cannot exclude the presence of additional mutations in the non-coding region of the UPB1 gene. Analysis of a human ßUP homology model revealed that the effects of the mutations (p.G31S, p.E271K, and p.R326Q) on enzyme activity are most likely linked to improper oligomer assembly. Highly variable phenotypes ranging from neurological involvement (including convulsions and autism) to asymptomatic, were observed in diagnosed patients. High prevalence of p.R326Q in the normal Japanese population indicates that ßUP deficiency is not as rare as generally considered and screening for ßUP deficiency should be included in diagnosis of patients with unexplained neurological abnormalities.

Pediatric palliative care across continents: Communication and shared-decision-making.

Despite the significant growth and development of pediatric palliative care worldwide, significant challenges remain. One of those challenges is shared decision-making, by which parents, families and professionals all work together to develop a plan of care that reflects both the medical facts and the patient's family's values. Shared decision-making about palliative care and about death and dying may mean different things in different cultures and countries. It is therefore important to learn and compare practices around the world.

How to move forward in shared decision-making in pediatric palliative care.

Pediatric palliative care has grown immensely in recent years in the world. However, shared decision-making remains a complex process, especially in pediatric palliative care. In particular, a number of issues are priorities to improve the shared decision-making process and ensure high-quality pediatric palliative care for every child. Working on these priorities will improve shared decision-making and thereby enhance high-quality pediatric palliative care around the globe.

Role of human hypoxanthine guanine phosphoribosyltransferase in activation of the antiviral agent T-705 (favipiravir).

6-Fluoro-3-hydroxy-2-pyrazinecarboxamide (T-705) is a novel antiviral compound with broad activity against influenza virus and diverse RNA viruses. Its active metabolite, T-705-ribose-5'-triphosphate (T-705-RTP), is recognized by influenza virus RNA polymerase as a substrate competing with GTP, giving inhibition of viral RNA synthesis and lethal virus mutagenesis. Which enzymes perform the activation of T-705 is unknown. We here demonstrate that human hypoxanthine guanine phosphoribosyltransferase (HGPRT) converts T-705 into its ribose-5'-monophosphate (RMP) prior to formation of T-705-RTP. The anti-influenza virus activity of T-705 and T-1105 (3-hydroxy-2-pyrazinecarboxamide; the analog lacking the 6-fluoro atom) was lost in HGPRT-deficient Madin-Darby canine kidney cells. This HGPRT dependency was confirmed in human embryonic kidney 293T cells undergoing HGPRT-specific gene knockdown followed by influenza virus ribonucleoprotein reconstitution. Knockdown for adenine phosphoribosyltransferase (APRT) or nicotinamide phosphoribosyltransferase did not change the antiviral activity of T-705 and T-1105. Enzymatic assays showed that T-705 and T-1105 are poor substrates for human HGPRT having Km(app) values of 6.4 and 4.1 mM, respectively. Formation of the RMP metabolites by APRT was negligible, and so was the formation of the ribosylated metabolites by human purine nucleoside phosphorylase. Phosphoribosylation and antiviral activity of the 2-pyrazinecarboxamide derivatives was shown to require the presence of the 3-hydroxyl but not the 6-fluoro substituent. The crystal structure of T-705-RMP in complex with human HGPRT showed how this compound binds in the active site. Since conversion of T-705 by HGPRT appears to be inefficient, T-705-RMP prodrugs may be designed to increase the antiviral potency of this new antiviral agent.

ß-ureidopropionase deficiency: phenotype, genotype and protein structural consequences in 16 patients.

ß-ureidopropionase is the third enzyme of the pyrimidine degradation pathway and catalyzes the conversion of N-carbamyl-ß-alanine and N-carbamyl-ß-aminoisobutyric acid to ß-alanine and ß-aminoisobutyric acid, ammonia and CO(2). To date, only five genetically confirmed patients with a complete ß-ureidopropionase deficiency have been reported. Here, we report on the clinical, biochemical and molecular findings of 11 newly identified ß-ureidopropionase deficient patients as well as the analysis of the mutations in a three-dimensional framework. Patients presented mainly with neurological abnormalities (intellectual disabilities, seizures, abnormal tonus regulation, microcephaly, and malformations on neuro-imaging) and markedly elevated levels of N-carbamyl-ß-alanine and N-carbamyl-ß-aminoisobutyric acid in urine and plasma. Analysis of UPB1, encoding ß-ureidopropionase, showed 6 novel missense mutations and one novel splice-site mutation. Heterologous expression of the 6 mutant enzymes in Escherichia coli showed that all mutations yielded mutant ß-ureidopropionase proteins with significantly decreased activity. Analysis of a homology model of human ß-ureidopropionase generated using the crystal structure of the enzyme from Drosophila melanogaster indicated that the point mutations p.G235R, p.R236W and p.S264R lead to amino acid exchanges in the active site and therefore affect substrate binding and catalysis. The mutations L13S, R326Q and T359M resulted most likely in folding defects and oligomer assembly impairment. Two mutations were identified in several unrelated ß-ureidopropionase patients, indicating that ß-ureidopropionase deficiency may be more common than anticipated.

The resilience of Jewish communities living in the diaspora: a scoping review.

Introduction: Throughout history, Jewish communities have been exposed to collectively experienced traumatic events. Little is known about the role that the community plays in the impact of these traumatic events on Jewish diaspora people. This scoping review aims to map the concepts of the resilience of Jewish communities in the diaspora and to identify factors that influence this resilience. Methods: We followed the Joanna Briggs Institute (JBI) methodology. Database searches yielded 2,564 articles. Sixteen met all inclusion criteria. The analysis was guided by eight review questions. Results: Community resilience of the Jewish diaspora was often described in terms of coping with disaster and struggling with acculturation. A clear definition of community resilience of the Jewish diaspora was lacking. Social and religious factors, strong organizations, education, and communication increased community resilience. Barriers to the resilience of Jewish communities in the diaspora included the interaction with the hosting country and other communities, characteristics of the community itself, and psychological and cultural issues. Discussion: Key gaps in the literature included the absence of quantitative measures of community resilience and the lack of descriptions of how community resilience affects individuals' health-related quality of life. Future studies on the interaction between community resilience and health-related individual resilience are warranted.

Improvement and implementation of a national individual care plan in paediatric palliative care: a study protocol.

INTRODUCTION: Paediatric palliative care (PPC) is care for children with life-threatening or life-limiting conditions, and can involve complex high-tech care, which can last for months or years. In 2015, the National Individual Care Plan (ICP) for PPC was developed and has shown to be successful. The ICP can be seen as an instrument to facilitate coordination, quality and continuity of PPC. However, in practice, an ICP is often completed too late and for too few children. We aim to improve the coordination, quality and continuity of care for every child with a life-threatening or life-limiting condition and his/her family by further developing and implementing the ICP in the Netherlands. METHODS AND ANALYSIS: To evaluate the original ICP, ICP 1.0, interviews and questionnaires will be held among parents of children who have or have had an ICP 1.0 and healthcare professionals (HCPs) who used ICP 1.0. Based on the results, ICP 1.0 will be further developed. An implementation strategy will be written and the renewed ICP, ICP 2.0, will be nationally tested in an implementation period of approximately 7 months. During the implementation period, ICP 2.0 will be used for all children who are registered with Children's Palliative Care teams. After the implementation period, ICP 2.0 will be evaluated using interviews and questionnaires among parents of children who received ICP 2.0 and HPCs who worked with ICP 2.0. Based on these results, ICP 2.0 will be further optimised into the final version: ICP 3.0. ETHICS AND DISSEMINATION: This study received ethical approval. The ICP 3.0 will be disseminated through the Dutch Centre of Expertise in Children's Palliative Care, to ensure wide availability for the general public and HCPs within PPC. Additionally, we aim to publish study results in open-access, peer-reviewed journals and to present results at national and international scientific meetings.