Assessment of carnitine excretion and its ratio to plasma free carnitine as a biomarker for primary carnitine deficiency in newborns

In the Netherlands, newborns are referred by the newborn screening (NBS) Program when a low free carnitine (C0) concentration (&lt;5 μmol/l) is detected in their NBS dried blood spot. This leads to ~85% false positive referrals who all need an invasive, expensive and lengthy evaluation. We investigated whether a ratio of urine C0 / plasma C0 (RatioU:P) can improve the follow-up protocol for primary carnitine deficiency (PCD). A retrospective study was performed in all Dutch metabolic centres, using samples from newborns and mothers referred by NBS due to low C0 concentration. Samples were included when C0 excretion and plasma C0 concentration were sampled on the same day. RatioU:P was calculated as (urine C0 [μmol/mmol creatinine])/(plasma C0 [μmol/l]). Data were available for 59 patients with genetically confirmed PCD and 68 individuals without PCD. The RatioU:P in PCD patients was significantly higher (p value &lt; 0.001) than in those without PCD, median [IQR], respectively: 3.4 [1.2–9.5], 0.4 [0.3–0.8], area under the curve (AUC) 0.837. Classified for age (up to 1 month) and without carnitine suppletion (PCD; N = 12, Non-PCD; N = 40), medians were 6.20 [4.4–8.8] and 0.37 [0.24–0.56], respectively. The AUC for RatioU:P was 0.996 with a cut-off required for 100% sensitivity at 1.7 (yielding one false positive case). RatioU:P accurately discriminates between positive and false positive newborn referrals for PCD by NBS. RatioU:P is less effective as a discriminative tool for PCD in adults and for individuals that receive carnitine suppletion.</p

Impaired Cognitive Functioning in Patients with Tyrosinemia Type I Receiving Nitisinone

ObjectiveTo examine cognitive functioning in patients with tyrosinemia type I treated with nitisinone and a protein-restricted diet.Study designWe performed a cross-sectional study to establish cognitive functioning in children with tyrosinemia type I compared with their unaffected siblings. Intelligence was measured using age-appropriate Wechsler Scales. To assess cognitive development over time, we retrieved sequential IQ scores in a single-center subset of patients. We also evaluated whether plasma phenylalanine and tyrosine levels during treatment was correlated with cognitive development.ResultsAverage total IQ score in 10 patients with tyrosinemia type I receiving nitisinone was significantly lower compared with their unaffected siblings (71 ± 13 vs 91 ± 13; P = .008). Both verbal and performance IQ subscores differed (77 ± 14 vs 95 ± 11; P < .05 and 70 ± 11 vs 87 ± 15; P < .05, respectively). Repeated IQ measurements in a single-center subset of 5 patients revealed a decline in average IQ score over time, from 96 ± 15 to 69 ± 11 (P < .001). No significant association was found between IQ score and either plasma tyrosine or phenylalanine concentration.ConclusionPatients with tyrosinemia type I treated with nitisinone are at risk for impaired cognitive function despite a protein-restricted diet

WEE1 inhibition synergizes with CHOP chemotherapy and radiation therapy through induction of premature mitotic entry and DNA damage in diffuse large B-cell lymphoma

Background: Diffuse large B-cell lymphoma (DLBCL) is a heterogeneous disease, characterized by high levels of genomic instability and the activation of DNA damage repair pathways. We previously found high expression of the cell cycle regulator WEE1 in DLBCL cell lines. Here, we investigated the combination of the WEE1 inhibitor, AZD1775, with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) and radiation therapy (RT), with the aim of improving first-line treatment.Methods: Cell viability experiments were performed to determine synergistic combinations. Levels of DNA damage were established using flow cytometry for γH2AX and protein analysis for DNA damage response proteins CHK1 and CHK2. Flow cytometry analysis for cell cycle and pH3 were performed to determine cell cycle distribution and premature mitotic entry.Results: Treatment with either RT or CHOP led to enhanced sensitivity to AZD1775 in several DLBCL cell lines. Treatment of cells with AZD1775 induced unscheduled mitotic progression, resulting in abnormal cell cycle distribution in combination with RT or CHOP treatment. In addition, a significant increase in DNA damage was observed compared with CHOP or RT alone. Of the single CHOP components, doxorubicin showed the strongest effect together with AZD1775, reducing viability and increasing DNA damage.Conclusion: In conclusion, the combination of RT or CHOP with AZD1775 enhances sensitivity to WEE1 inhibition through unscheduled G2/M progression, leading to increased DNA damage. Based on these results, WEE1 inhibition has great potential together with other G2/M arresting or DNA damaging (chemo) therapeutic compounds and should be further explored in clinical trials.</p

Rescue of Salivary Gland Function after Stem Cell Transplantation in Irradiated Glands

Head and neck cancer is the fifth most common malignancy and accounts for 3% of all new cancer cases each year. Despite relatively high survival rates, the quality of life of these patients is severely compromised because of radiation-induced impairment of salivary gland function and consequential xerostomia (dry mouth syndrome). In this study, a clinically applicable method for the restoration of radiation-impaired salivary gland function using salivary gland stem cell transplantation was developed. Salivary gland cells were isolated from murine submandibular glands and cultured in vitro as salispheres, which contained cells expressing the stem cell markers Sca-1, c-Kit and Musashi-1. In vitro, the cells differentiated into salivary gland duct cells and mucin and amylase producing acinar cells. Stem cell enrichment was performed by flow cytrometric selection using c-Kit as a marker. In vitro, the cells differentiated into amylase producing acinar cells. In vivo, intra-glandular transplantation of a small number of c-Kit+ cells resulted in long-term restoration of salivary gland morphology and function. Moreover, donor-derived stem cells could be isolated from primary recipients, cultured as secondary spheres and after re-transplantation ameliorate radiation damage. Our approach is the first proof for the potential use of stem cell transplantation to functionally rescue salivary gland deficiency

Whole body composition analysis by the BodPod air-displacement plethysmography method in children with phenylketonuria shows a higher body fat percentage

BACKGROUND: Phenylketonuria (PKU) causes irreversible central nervous system damage unless a phenylalanine (PHE) restricted diet with amino acid supplementation is maintained. To prevent growth retardation, a protein/amino acid intake beyond the recommended dietary protein allowance is mandatory. However, data regarding disease and/or diet related changes in body composition are inconclusive and retarded growth and/or adiposity is still reported. The BodPod whole body air-displacement plethysmography method is a fast, safe and accurate technique to measure body composition. AIM: To gain more insight into the body composition of children with PKU. METHODS: Patients diagnosed with PKU born between 1991 and 2001 were included. Patients were identified by neonatal screening and treated in our centre. Body composition was measured using the BodPod system (Life Measurement Incorporation©). Blood PHE values determined every 1–3 months in the year preceding BodPod analysis were collected. Patients were matched for gender and age with data of healthy control subjects. Independent samples t tests, Mann–Whitney and linear regression were used for statistical analysis. RESULTS: The mean body fat percentage in patients with PKU (n = 20) was significantly higher compared to healthy controls (n = 20) (25.2% vs 18.4%; p = 0.002), especially in girls above 11 years of age (30.1% vs 21.5%; p = 0.027). Body fat percentage increased with rising body weight in patients with PKU only (R = 0.693, p = 0.001), but did not correlate with mean blood PHE level (R = 0.079, p = 0.740). CONCLUSION: Our data show a higher body fat percentage in patients with PKU, especially in girls above 11 years of age

Prediction of disease severity in multiple acyl-CoA dehydrogenase deficiency:a retrospective and laboratory cohort study

Multiple acyl-CoA dehydrogenase deficiency (MADD) is an ultra-rare inborn error of mitochondrial fatty acid oxidation (FAO) and amino acid metabolism. Individual phenotypes and treatment response can vary markedly. We aimed to identify markers that predict MADD phenotypes. We performed a retrospective nationwide cohort study; then developed an MADD-disease severity scoring system (MADD-DS3) based on signs and symptoms with weighed expert opinions; and finally correlated phenotypes and MADD-DS3 scores to FAO flux (oleate and myristate oxidation rates) and acylcarnitine profiles after palmitate loading in fibroblasts. Eighteen patients, diagnosed between 1989 and 2014, were identified. The MADD-DS3 entails enumeration of eight domain scores, which are calculated by averaging the relevant symptom scores. Lifetime MADD-DS3 scores of patients in our cohort ranged from 0 to 29. FAO flux and [U-13C]C2-, C5-, and [U-13C]C16-acylcarnitines were identified as key variables that discriminated neonatal from later onset patients (all P <.05) and strongly correlated to MADD-DS3 scores (oleate: r = −.86; myristate: r = −.91; [U-13C]C2-acylcarnitine: r = −.96; C5-acylcarnitine: r =.97; [U-13C]C16-acylcarnitine: r =.98, all P <.01). Functional studies in fibroblasts were found to differentiate between neonatal and later onset MADD-patients and were correlated to MADD-DS3 scores. Our data may improve early prediction of disease severity in order to start (preventive) and follow-up treatment appropriately. This is especially relevant in view of the inclusion of MADD in population newborn screening programs

Analyse des PI3K-Signalwegs bei der Entstehung des duktalen Pankreaskarzinoms

Job rotation is often advocated to reduce workload, but its efficacy has seldom been investigated. The aim of this study is to compare the work demands, workload, and recovery among truck driving, refuse collecting, and rotating between these two jobs, between days and during the day. Three teams of 3 employees each participated in this study. Work demands were assessed by systematic observation of tasks and activities. Workload was quantified by means of heart rate, oxygen uptake, subjective ratings, and urinary excretion rates of catecholamines. Recovery was quantified by excretion rates of catecholamines after work. Job rotation between driving and collecting is an effective measure to reduce physical workload as compared with collecting only and to decrease mental workload as compared with driving only. However, job rotation resulted. in increased physical workload as compared with driving only. Job rotation did not increase mental workload as compared with collecting only. No effects were seen on recovery. No differences were found between rotating between days and during the day. Actual or potential applications of this research include the recommendation that before job rotation is introduced, its efficacy be determined in terms of well-chosen workload measures because a reduction in work demands does not directly imply a reduction in workload. Therefore, job rotation might be less effective than expecte

Renal uptake of different radiolabelled peptides is mediated by megalin: SPECT and biodistribution studies in megalin-deficient mice

Contains fulltext : 98302.pdf (publisher's version ) (Closed access)PURPOSE: Radiolabelled peptides used for peptide receptor radionuclide therapy are excreted mainly via the kidneys and are partly reabsorbed and retained in the proximal tubular cells. The resulting high renal radiation dose can cause nephrotoxicity, limiting the maximum activity dose and the effectiveness of peptide receptor radionuclide therapy. The mechanisms of kidney reabsorption of these peptides are incompletely understood, but the scavenger receptor megalin has been shown to play a role in the reabsorption of (111)In-octreotide. In this study, the role of megalin in the renal reabsorption of various relevant radiolabelled peptides was investigated. METHODS: Groups of kidney-specific megalin-deficient mice and wild-type mice were injected with (111)In-labelled somatostatin, exendin, neurotensin or minigastrin analogues. Single photon emission computed tomographic (SPECT) images of the kidneys were acquired and analysed quantitatively, or the animals were killed 3 h after injection and the activity concentration in the kidneys was measured. RESULTS: Megalin-deficient mice showed significantly lower uptake of all studied radiolabelled peptides in the kidneys, ranging from 22% ((111)In-octreotide) to 65% ((111)In-exendin) of uptake in wild-type kidneys. Quantitative analysis of renal uptake by SPECT and ex vivo measurements showed a very good correlation. CONCLUSION: Megalin is involved in the renal reabsorption of radiolabelled octreotide, octreotate, exendin, neurotensin and minigastrin. This knowledge may help in the design of strategies to reduce this reabsorption and the resulting nephrotoxicity in peptide receptor radionuclide therapy, enabling more effective therapy. Small-animal SPECT is an accurate tool, allowing in vivo quantification of renal uptake and serial measurements in individual mice

Influence of green tea consumption on endoxifen steady-state concentration in breast cancer patients treated with tamoxifen

Background: Many cancer patients use additional herbs or supplements in combination with their anti-cancer therapy. Green tea—active ingredient epigallocatechin-3-gallate (EGCG)—is one of the most commonly used dietary supplements among breast cancer patients. EGCG may alter the metabolism of tamoxifen. Therefore, the aim of this study was to investigate the influence of green tea supplements on the pharmacokinetics of endoxifen; the most relevant active metabolite of tamoxifen. Methods: In this single-center, randomized cross-over trial, effects of green tea capsules on endoxifen levels were evaluated. Patients treated with tamoxifen for at least 3 months were eligible for this study. After inclusion, patients were consecutively treated with tamoxifen monotherapy for 28 days and in combination with green tea supplements (1 g twice daily; containing 300 mg EGCG) for 14 days (or vice versa). Blood samples were collected on the last day of monotherapy or combination therapy. Area under the curve (AUC0–24h), maximum concentration (Cmax) and minimum concentration (Ctrough) were obtained from individual plasma concentration–time curves. Results: No difference was found in geometric mean endoxifen AUC0–24h in the period with green tea versus tamoxifen monotherapy (− 0.4%; 95% CI − 8.6 to 8.5%; p = 0.92). Furthermore, no differences in Cmax (− 2.8%; − 10.6 to 5.6%; p = 0.47) nor Ctrough (1.2%; − 7.3 to 10.5%; p = 0.77) were found. Moreover, no severe toxicity was reported during the whole study period. Conclusions: This study demonstrated the absence of a pharmacokinetic interaction between green tea supplements and tamoxifen. Therefore, the use of green tea by patients with tamoxifen does not have to be discouraged