ABSTRACT
There have been predictions that the use of the macrocyclic chelating agent 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA) in zirconium-89 (89Zr) immuno-positron emission tomography (89Zr-immunoPET) could enhance the in vivo stability of 89Zr radioimmunoconjugates. However, conjugating [89Zr]Zr-DOTA to a monoclonal antibody (mAb) remains a challenge as the heat treatment required for [89Zr]Zr-DOTA chelation can lead to thermal denaturation of the mAb moieties. We developed a method for synthesizing [89Zr]Zr-DOTA-mAb based on a tetrazine (Tz)-conjugated bifunctional DOTA derivative 2,2',2â³-(10-(1-(4-(1,2,4,5-tetrazin-3-yl)phenyl)-3,21,26-trioxo-6,9,12,15,18-pentaoxa-29-carboxy-2,22,25-triazanonacosane-29-yl)-1,4,7,10-tetraazacyclododecane-1,4,7-triyl)triacetic acid (DOTAGA-Tz) and the inverse electron-demand Diels-Alder (IEDDA) click chemistry reaction where trans-cyclooctene-modified mAbs are conjugated to [89Zr]Zr-DOTAGA without being exposed to heat. The stability of IEDDA-derived [89Zr]Zr-DOTAGA-trastuzumab was confirmed by in vitro, ex vivo, and in vivo testing and comparative analysis against the conventional deferoxamine (DFO) counterpart [89Zr]Zr-DFO-trastuzumab. The in vivo immunoPET imaging using [89Zr]Zr-DOTAGA-trastuzumab clearly visualized human epidermal growth factor receptor 2-positive malignancies in murine xenograft models. Greater tumor contrast was observed from [89Zr]Zr-DOTAGA-trastuzumab at a 72-h delayed scan compared with [89Zr]Zr-DFO-trastuzumab. These findings suggest that our IEDDA ligation approach can be an effective means of synthesizing [89Zr]Zr-DOTA-mAb and can enhance the theranostic potential of 89Zr-immunoPET in DOTA-mediated radioimmunotherapy.
ABSTRACT
Acid sphingomyelinase deficiency (ASMD) and Gaucher disease (GD) are lysosomal storage disorders associated with hepatosplenomegaly and thrombocytopenia. The incidences of ASMD and GD are known to be particularly high in the Ashkenazi Jewish population. Conversely, the number of reported patients with these diseases has been limited in Asian countries, including Japan. Here, we reviewed the allele frequencies of pathogenic variants causing ASMD and GD in the Japanese population and populations with various ancestry backgrounds using the Japanese Multi-Omics Reference Panel 54KJPN and the Genome Aggregation Database v4.0.0. The estimated carrier frequencies of ASMD- and GD-related variants were 1/180 and 1/154 in Japanese individuals, equivalent to disease occurrence frequencies of 1/128,191 and 1/94,791 individuals, respectively. These frequencies are much higher than previously expected. Our data also suggest that there are more patients with a milder form of ASMD and nonspecific clinical findings who have not yet been diagnosed.
ABSTRACT
OBJECTIVES: Adverse events (AEs) represent an important cause of morbidity and mortality for pediatric inpatients; however, reports on their epidemiology in pediatrics, especially outside Western countries, are scarce. We investigated the incidence and nature of AEs in pediatric inpatients in Japan. METHODS: Trained pediatrician and pediatric nurses reviewed all medical documents of 1126 pediatric inpatients in 2 tertiary care teaching hospitals in Japan, and potential incidents were collected with patients' characteristics. Age was categorized into 6 groups (neonates, infants, preschoolers, school-aged children, teenagers, and over-aged pediatric patients), and medical care when potential incidents occurred was classified into drug, operation, procedure/examinations, nursing, management, and judgment. Physician reviewers independently evaluated all collected incidents into AEs, potential AEs, medical errors, and exclusions and assessed their severity and preventability. RESULTS: A total of 1126 patients with 12,624 patient-days were enrolled, and 953 AEs, with an incidence of 76 (95% confidence interval, 71-80) per 1000 patient-days, were identified. Preventable AEs accounted for 23% (218/953) of AEs. The incidence of AEs tended to decrease with increasing age. The proportion of AEs that were preventable was highest in neonates (40%), and this proportion decreased as children aged. Both judgment and management-related AEs were considered preventable AEs, and judgment-related AEs were more severe AEs than no-judgment-related AEs; 43% were life-threatening. CONCLUSIONS: Adverse events were common in Japanese pediatric inpatients, and their preventability and severity varied considerably by age category and medical care. Further investigation is needed to address which strategies might most improve pediatric patient safety.
Subject(s)
Inpatients , Medical Errors , Infant , Infant, Newborn , Adolescent , Child , Humans , Japan/epidemiology , Patient Safety , Incidence , Retrospective StudiesABSTRACT
Gaucher disease type 3 is a chronic neuronopathic disorder with wide-ranging effects, including hepatosplenomegaly, anaemia, thrombocytopenia, skeletal disease and diverse neurological manifestations. Biallelic mutations in GBA1 reduce lysosomal acid ß-glucosidase activity, and its substrates, glucosylceramide and glucosylsphingosine, accumulate. Enzyme replacement therapy and substrate reduction therapy ameliorate systemic features of Gaucher disease, but no therapies are approved for neurological manifestations. Venglustat is an investigational, brain-penetrant, glucosylceramide synthase inhibitor with potential to improve the disease by rebalancing influx of glucosylceramide with impaired lysosomal recycling. The Phase 2, open-label LEAP trial (NCT02843035) evaluated orally administered venglustat 15 mg once-daily in combination with maintenance dose of imiglucerase enzyme replacement therapy during 1 year of treatment in 11 adults with Gaucher disease type 3. Primary endpoints were venglustat safety and tolerability and change in concentration of glucosylceramide and glucosylsphingosine in CSF from baseline to Weeks 26 and 52. Secondary endpoints included change in plasma concentrations of glucosylceramide and glucosylsphingosine, venglustat pharmacokinetics in plasma and CSF, neurologic function, infiltrative lung disease and systemic disease parameters. Exploratory endpoints included changes in brain volume assessed with volumetric MRI using tensor-based morphometry, and resting functional MRI analysis of regional brain activity and connectivity between resting state networks. Mean (SD) plasma venglustat AUC0-24 on Day 1 was 851 (282) ngâ¢h/ml; Cmax of 58.1 (26.4) ng/ml was achieved at a median tmax 2.00 h. After once-daily venglustat, plasma concentrations (4 h post-dose) were higher compared with Day 1, indicating â¼2-fold accumulation. One participant (Patient 9) had low-to-undetectable venglustat exposure at Weeks 26 and 52. Based on mean plasma and CSF venglustat concentrations (excluding Patient 9), steady state appeared to be reached on or before Week 4. Mean (SD) venglustat concentration at Week 52 was 114 (65.8) ng/ml in plasma and 6.14 (3.44) ng/ml in CSF. After 1 year of treatment, median (inter-quartile range) glucosylceramide decreased 78% (72, 84) in plasma and 81% (77, 83) in CSF; median (inter-quartile range) glucosylsphingosine decreased 56% (41, 60) in plasma and 70% (46, 76) in CSF. Ataxia improved slightly in nine patients: mean (SD, range) total modified Scale for Assessment and Rating of Ataxia score decreased from 2.68 [1.54 (0.0 to 5.5)] at baseline to 1.55 [1.88 (0.0 to 5.0)] at Week 52 [mean change: -1.14 (95% CI: -2.06 to -0.21)]. Whole brain volume increased slightly in patients with venglustat exposure and biomarker reduction in CSF (306.7 ± 4253.3 mm3) and declined markedly in Patient 9 (-13894.8 mm3). Functional MRI indicated stronger connectivity at Weeks 26 and 52 relative to baseline between a broadly distributed set of brain regions in patients with venglustat exposure and biomarker reduction but not Patient 9, although neurocognition, assessed by Vineland II, deteriorated in all domains over time, which illustrates disease progression despite the intervention. There were no deaths, serious adverse events or discontinuations. In adults with Gaucher disease type 3 receiving imiglucerase, addition of once-daily venglustat showed acceptable safety and tolerability and preliminary evidence of clinical stability with intriguing but intrinsically inconsistent signals in selected biomarkers, which need to be validated and confirmed in future research.
Subject(s)
Gaucher Disease , Nervous System Diseases , Humans , Adult , Glucosylceramidase/therapeutic use , Glucosylceramidase/genetics , Gaucher Disease/drug therapy , Gaucher Disease/genetics , Glucosylceramides/therapeutic use , Chronic Disease , Biomarkers , Nervous System Diseases/drug therapy , AtaxiaABSTRACT
BACKGROUND: Gaucher disease (GD) is an autosomal recessive disease caused by GBA1 mutations resulting in glucosylceramide accumulation in macrophages. GD is characterized by hepatosplenomegaly, anemia, thrombocytopenia, bone complications, and neurological complications. Glucosylsphingosine (lyso-Gb1), a deacylated form of glucosylceramide, has been identified as a promising biomarker for the diagnosis and treatment response in GD. The aim of this study was to examine the relationship between plasma lyso-Gb1 and therapeutic goals for GD (improvements in hepatomegaly, splenomegaly, anemia, thrombocytopenia, bone pain, and bone crisis), as well as disease type and GBA1 mutation type, in Japanese patients with GD receiving velaglucerase alfa, an enzyme replacement therapy (ERT). Furthermore, this study compared the plasma lyso-Gb1 concentration observed in Japanese patients included in this study with that observed in a previous non-Japanese clinical study. RESULTS: This non-interventional, open-label, multicenter observational cohort study (October 2020 to March 2021) included a total of 20 patients (of any age) with GD (type 1: n = 8; type 2: n = 9; type 3: n = 3) treated with velaglucerase alfa for ≥ 3 months. Median (minimum-maximum) duration of velaglucerase alfa treatment was 49.5 (3-107) months. A total of 14 (70.0%) patients achieved all therapeutic goals (i.e., 100% achievement; improvements in hepatomegaly, splenomegaly, anemia, thrombocytopenia, bone pain, and bone crisis). Overall, median (minimum-maximum) lyso-Gb1 concentration was 24.3 (2.1-150) ng/mL. Although not statistically significant, numerically lower plasma lyso-Gb1 concentrations were observed in patients with 100% achievement compared with those without; no statistically significant difference in plasma lyso-Gb1 concentration was observed between patients with different disease type or mutation type. Furthermore, lyso-Gb1 concentrations observed in Japanese patients were numerically lower than that observed in a previous study of non-Japanese patients with GD receiving ERT. CONCLUSIONS: In this study, high achievement rates of therapeutic goals with low lyso-Gb1 concentration were observed, demonstrating a correlation between therapeutic goals and lower plasma lyso-Gb1 concentration in Japanese patients with GD treated with velaglucerase alfa. This study further suggests that plasma lyso-Gb1 concentration may be a useful biomarker for treatment response in patients with GD.
Subject(s)
Gaucher Disease , Thrombocytopenia , Humans , Gaucher Disease/diagnosis , Glucosylceramides/therapeutic use , Splenomegaly/chemically induced , Splenomegaly/drug therapy , Hepatomegaly/chemically induced , Hepatomegaly/drug therapy , Glucosylceramidase/genetics , Enzyme Replacement Therapy/methods , Treatment Outcome , Biomarkers , Thrombocytopenia/chemically induced , Thrombocytopenia/drug therapy , Pain/drug therapyABSTRACT
[This corrects the article DOI: 10.1016/j.omtm.2022.04.012.].
ABSTRACT
Aims: T1 mapping in cardiac magnetic resonance imaging enables us to distinguish various myocardial diseases showing left ventricular hypertrophy. Fabry disease is a lysosomal storage disorder causing the accumulation of glycosphingolipids into various organs, including the heart, which can be detected by native T1 values in T1 mapping. However, there is no report for the systematic evaluation of native T1 values in Fabry disease in Japan. Methods and results: We analyzed native T1 values of 30 Fabry disease patients (14 males and 16 females) obtained by 3-T cardiac magnetic resonance imaging. Averaged T1 values were significantly lower in male patients (septal T1: 1149.5 ± 63.3 ms; total T1: 1145.1 ± 59.5 ms) than in female patients (septal T1: 1210.5 ± 45.5 ms; total T1: 1198.8 ± 51.8 ms) (p < 0.01). We compared the native T1 values of Fabry disease patients with those obtained from 15 hypertrophic cardiomyopathy patients (9 males and 6 females). Native T1 values effectively differentiate Fabry disease from hypertrophic cardiomyopathy (septal T1: sensitivity 93.3% and specificity 80.0%; total T1: sensitivity 86.7% and specificity 73.3%). In addition, native T1 values had a significant negative correlation with the left ventricular mass index in male patients at the pre-hypertrophic stage (p < 0.05). In male and female patients without late-gadolinium enhancement, native T1 values also had a significant negative correlation with the left ventricular mass index (p < 0.05). Conclusion: These results suggest that native T1 values can be used to discriminate Fabry disease from hypertrophic cardiomyopathy and can reflect the accumulation of glycosphingolipids in cardiomyocytes.
ABSTRACT
GM1-gangliosidosis is a progressive neurodegenerative glycosphingolipidosis resulting from a GLB1 gene mutation causing a deficiency of the lysosomal enzyme ß-galactosidase, which leads to the abnormal accumulation of GM1 ganglioside in the central nervous system. In the most severe early infantile phenotype, excessive ganglioside accumulation results in a rapid decline in neurological and psychomotor functions, and death occurs within 2 years of age. Currently, there is no effective therapy for GM1-gangliosidosis. In this study, we evaluated the therapeutic efficacy of ex vivo gene therapy targeting hematopoietic stem cells using a lentiviral vector to increase enzyme activity, reduce substrate accumulation, and improve astrocytosis and motor function. Transplanting GLB1-transduced hematopoietic stem cells in mice increased ß-galactosidase enzyme activity in the central nervous system and visceral organs. Specifically, this gene therapy significantly decreased GM1 ganglioside levels in the brain, especially in the cerebrum. More important, this gene therapy rectified astrocytosis in the cerebrum and improved motor function deficits. Furthermore, the elevation of serum ß-galactosidase activity in secondary-transplanted mice suggested the ability of transduced hematopoietic stem cells to repopulate long term. These data indicate that ex vivo gene therapy with lentiviral vectors is a promising approach for the treatment of brain deficits in GM1 gangliosidosis.
ABSTRACT
OBJECTIVE: This study aimed to gain an understanding of patient and physician satisfaction with overall treatment and routine consultations for Parkinson's disease in clinical practice. METHODS: This observational, cross-sectional, web-based survey was conducted in Japan from February to March 2019. Eligible patients with Parkinson's disease (N = 186) and physicians who treat patients with Parkinson's disease (N = 331) were asked to evaluate their satisfaction with treatment, consultation, symptom control, and use of a symptom diary. RESULTS: Patients had a mean age of 62.7 years, 54.8% were male, and most (75.8%) had Hoehn and Yahr stage ≥3 symptoms. Physicians were mostly male (93.1%) and had treated 52 patients with Parkinson's disease in the last 6 months, and 34.1% were certified neurologists. There were significant gaps between patient and physician satisfaction with treatment and consultations. Patient and physician satisfaction with overall treatment was significantly lower for patients with Hoehn and Yahr stage ≥3 symptoms than stage 1-2 symptoms (patients: 53.9% vs. 71.1%; physicians: 43.2% vs. 69.7%, respectively). The proportion of patients who were satisfied with symptom control was lower than that of physicians (26.4% vs. 51.5%). Influencing factors for patient satisfaction with treatment were nonmotor symptoms (e.g., insomnia and depression). Satisfaction tended to be higher for patients and physicians when symptom diaries were used. CONCLUSION: Significant gaps in perceptions of treatment and consultation exist between patients and physicians in Parkinson's disease. Physicians should participate in shared decision making with their patients and consider strategies for management of nonmotor symptoms and nonpharmacological therapies and encourage the use of symptom diaries.
ABSTRACT
PURPOSE: We report the case of a patient with progressive myoclonus epilepsy due to Gaucher disease type 3 whose seizures and ability to perform activities of daily living were significantly improved after starting low-dose perampanel therapy. CASE: Our patient's generalized tonic-clonic seizures and myoclonus did not improve despite the administration of multiple antiseizure medications and enzyme replacement therapy. The myoclonus reduced following pharmacological chaperone therapy, but this effect was temporary, and the generalized tonic-clonic seizures continued to occur. However, the generalized tonic-clonic seizures disappeared following treatment with 2 mg/day of perampanel. In addition, the decrease in myoclonus dramatically improved motor function such as talking, eating, and walking and stabilized the patient's mental status. These effects have been sustained for more than 4 years. CONCLUSION: Perampanel is expected to be effective in the treatment of progressive myoclonus epilepsy associated with Gaucher disease type 3 and should be considered the drug of choice for this condition.
Subject(s)
Anticonvulsants/pharmacology , Gaucher Disease/complications , Myoclonic Epilepsies, Progressive/drug therapy , Myoclonic Epilepsies, Progressive/etiology , Nitriles/pharmacology , Pyridones/pharmacology , Anticonvulsants/administration & dosage , Humans , Nitriles/administration & dosage , Pyridones/administration & dosageABSTRACT
INTRODUCTION: Novel diagnostic and therapeutic options are urgently needed for patients with metastatic castration-resistant prostate cancer (CRPC). PSMA-617 is one of the most promising ligands that bind to prostate specific membrane antigen (PSMA), the cell surface biomarker of CRPC. Of the radiolabeled PSMA ligands developed to date, [68Ga]Ga-PSMA-617 is most commonly used for PSMA positron emission tomography (PET) prior to radioligand therapy (RLT) with [177Lu]Lu-PSMA-617. However, the presence of 68Ga radioactivity (half-life 68 m) in urine at the early PET imaging time point complicates optimization of the therapeutic dose of PSMA-617 labeled with 177Lu (half-life 6.7 d). Thus, PET imaging with the long-lived positron emitter 89Zr (half-life 3.3 d) would be better suited in order to optimize the dose of [177Lu]Lu-PSMA-617 as 89Zr PET allows scans after excretion of the radioactive urine. Until now, PSMA-617 could not be radiolabeled with 89Zr with high radiochemical yield due to poor incorporation of 89Zr into 1,4,7,10-tetraazacyclododecane-1,4,7,10-tetraacetic acid (DOTA). Here we report a novel method for radiolabeling PSMA-617 with 89Zr and the preliminary results of small-animal PET with [89Zr]Zr-PSMA-617. METHODS: We labeled PSMA-617 with 89Zr in a 1:1 mixture of DMSO and HEPES buffer at 90 °C for 30 min, followed by quality control analysis by HPLC. We then determined the dissociation constant (Kd) and logD values of [89Zr]Zr-PSMA-617. We obtained PET images of [89Zr]Zr-PSMA-617 at 24 h in mice bearing both LNCaP (PSMA-positive) and PC-3 (PSMA-negative) tumors (N = 5). The ex vivo [89Zr]Zr-PSMA-617 biodistribution was then examined separately using tissue samples of LNCaP-bearing mice at 2 h (N = 4) and 24 h (N = 4). RESULTS: [89Zr]Zr-PSMA-617 was prepared with a radiochemical yield of 70 ± 9%. The Kd value was 6.8 ± 3.5 nM. The logD value was -4.05 ± 0.20. PET images showed the highest uptake in LNCaP tumors (maximum standardized uptake value, SUVmax = 0.98 ± 0.32) and low uptake in kidneys (SUVmax = 0.18 ± 0.7) due to the absence of urine radioactivity. CONCLUSION: [89Zr]Zr-PSMA-617 was successfully prepared using DMSO and HEPES buffer. [89Zr]Zr-PSMA-617 visualized PSMA-positive LNCaP tumors in the absence of radioactive urine 24 h p.i. ADVANCES IN KNOWLEDGE AND IMPLICATIONS FOR PATIENT CARE: This method of radiolabeling PSMA-617 with 89Zr using DMSO would be suitable for future clinical trials. Prediction of radiation dose by using [89Zr]Zr-PSMA-617 leads to the safe and effective RLT with [177Lu]Lu-PSMA-617.
Subject(s)
Dimethyl Sulfoxide , Prostatic Neoplasms , Animals , Antigens, Surface/metabolism , Cell Line, Tumor , Dipeptides , Glutamate Carboxypeptidase II/metabolism , Heterocyclic Compounds, 1-Ring , Humans , Lutetium , Male , Mice , Positron Emission Tomography Computed Tomography/methods , Positron-Emission Tomography , Prostate-Specific Antigen , Prostatic Neoplasms/pathology , Radiopharmaceuticals , Tissue DistributionABSTRACT
BACKGROUND: Gaucher disease (GD) is caused by reduced lysosomal enzyme ß-glucocerebrosidase activity. Heterogeneous genotypes and phenotypes have been observed within GD types and across ethnicities. Enzyme replacement therapy is generally recommended for patients with type 1 GD, the least severe form of GD. In Japan, velaglucerase alfa has a broad indication covering type 1, 2 or 3 GD. METHODS: All patients with type 1, 2, or 3 GD administered velaglucerase alfa 60 U/kg every 2 weeks via intravenous infusion after its launch date in Japan in 2014, were enrolled in a non-interventional, observational post-marketing surveillance (PMS). Individual patient data were reported via case report forms (CRFs). Key safety endpoints investigated included the incidence of infusion-related reactions (IRRs), the safety of velaglucerase alfa in patients with types 2 and 3 GD, from patients under one year of age to elderly patients (≥ 65 years of age). Long-term efficacy was also assessed. RESULTS: In total, 53 patients with GD were registered. CRFs were available for 41 (77.4%) patients at the 6-year interim analysis. Fourteen adverse drug reactions (ADRs) were reported in seven patients. All reported ADRs occurred in patients with type 2 GD. ADRs were reported by 63.6% (7/11) of patients with type 2 GD. Ten ADRs were reported in five patients aged < 4 years. No elderly patients experienced any ADR during the surveillance period. Five ADRs occurring in three (10.0%) patients were classified as IRRs, with one case of vomiting (moderate severity) resulting in treatment discontinuation. Ten serious adverse events were reported in five (16.7%) patients. Three fatal events were considered to be unrelated to treatment with velaglucerase alfa. Platelet counts increased after the administration of velaglucerase alfa and were generally maintained within the normal range over the administration period. Among eleven patients tested for neutralizing anti-velaglucerase alfa antibodies, two (18.2%) were assessed as positive results. CONCLUSION: PMS data from patients with types 1-3 GD in Japan indicate that long-term treatment with velaglucerase alfa was well-tolerated and associated with increased platelet counts, which is consistent with observations made in studies outside of Japan. TRIAL REGISTRATION: NCT03625882 registered July 2014.
Subject(s)
Gaucher Disease , Glucosylceramidase , Aged , Enzyme Replacement Therapy/adverse effects , Enzyme Replacement Therapy/methods , Gaucher Disease/drug therapy , Gaucher Disease/genetics , Glucosylceramidase/adverse effects , Glucosylceramidase/genetics , Humans , Japan , Product Surveillance, Postmarketing , Treatment OutcomeABSTRACT
Gaucher disease is a rare genetic disorder caused by the deficiency of acid ß-glucosidase to effectively catalyze the degradation of glucosylceramide to glucose and ceramide. We report here the case of a 31-year-old male Japanese patient with Gaucher disease who switched from enzyme replacement therapy (ERT) to substrate reducing therapy (SRT). Liver dysfunction was identified at a routine medical checkup, and the patient was referred to our hospital with "idiopathic liver disease." Clinical laboratory tests indicated thrombocytopenia and splenomegaly, which are characteristic symptoms of Gaucher disease. To definitively diagnose Gaucher disease, a bone marrow biopsy and acid ß-glucosidase activity measurement were conducted; the results supported a diagnosis of Gaucher disease. This case emphasizes that it is possible for periodic medical checkups in adults to lead to the diagnosis of rare genetic disorders. The patient underwent ERT treatment with imiglucerase for 5 years; the platelet count rapidly increased and the spleen size rapidly decreased, indicating a good response to the drug. However, the patient increasingly felt the burden of visiting the hospital for 2 h of infusion ERT every 2 weeks. Consequently, it was jointly decided that he should switch from ERT to SRT with an oral drug. This switch was successful with no deterioration of laboratory data. This case report is the first to describe a Japanese Gaucher disease patient treated with eliglustat for >2 years. We showed that SRT is a well-tolerated and effective option for the treatment of Gaucher disease.
ABSTRACT
Synthesis of cytochrome c oxidase (Scox) is a Drosophila homolog of human SCO2 encoding a metallochaperone that transports copper to cytochrome c, and is an essential protein for the assembly of cytochrome c oxidase in the mitochondrial respiratory chain complex. SCO2 is highly conserved in a wide variety of species across prokaryotes and eukaryotes, and mutations in SCO2 are known to cause mitochondrial diseases such as fatal infantile cardioencephalomyopathy, Leigh syndrome, and Charcot-Marie-Tooth disease, a neurodegenerative disorder. These diseases have a common symptom of locomotive dysfunction. However, the mechanisms of their pathogenesis remain unknown, and no fundamental medications or therapies have been established for these diseases. In this study, we demonstrated that the glial cell-specific knockdown of Scox perturbs the mitochondrial morphology and function, and locomotive behavior in Drosophila. In addition, the morphology and function of synapses were impaired in the glial cell-specific Scox knockdown. Furthermore, Scox knockdown in ensheathing glia, one type of glial cell in Drosophila, resulted in larval and adult locomotive dysfunction. This study suggests that the impairment of Scox in glial cells in the Drosophila CNS mimics the pathological phenotypes observed by mutations in the SCO2 gene in humans.
Subject(s)
Drosophila Proteins , Drosophila melanogaster , Locomotion , Metallochaperones , Neuroglia/metabolism , Animals , Drosophila Proteins/genetics , Drosophila Proteins/physiology , Drosophila melanogaster/physiology , Metallochaperones/genetics , Metallochaperones/physiology , Mitochondria/metabolism , Mitochondria/pathology , Synapses/metabolismABSTRACT
(1) Background: Deferoxamine B (DFO) is the most widely used chelator for labeling of zirconium-89 (89Zr) to monoclonal antibody (mAb). Despite the remarkable developments of the clinical 89Zr-immuno-PET, chemical species and stability constants of the Zr-DFO complexes remain controversial. The aim of this study was to re-evaluate their stability constants by identifying species of Zr-DFO complexes and demonstrate that the stability constants can estimate radiochemical yield (RCY) and chelator-to-antibody ratio (CAR). (2) Methods: Zr-DFO species were determined by UV and ESI-MS spectroscopy. Stability constants and speciation of the Zr-DFO complex were redetermined by potentiometric titration. Complexation inhibition of Zr-DFO by residual impurities was investigated by competition titration. (3) Results: Unknown species, ZrHqDFO2, were successfully detected by nano-ESI-Q-MS analysis. We revealed that a dominant specie under radiolabeling condition (pH 7) was ZrHDFO, and its stability constant (logß111) was 49.1 ± 0.3. Competition titration revealed that residual oxalate inhibits Zr-DFO complex formation. RCYs in different oxalate concentration (0.1 and 0.04 mol/L) were estimated to be 86% and >99%, which was in good agreement with reported results (87%, 97%). (4) Conclusion: This study succeeded in obtaining accurate stability constants of Zr-DFO complexes and estimating RCY and CAR from accurate stability constants established in this study.
Subject(s)
Antibodies, Monoclonal/chemistry , Chelating Agents/chemistry , Deferoxamine/chemistry , Radioisotopes/chemistry , Zirconium/chemistry , Cell Line, Tumor , Humans , Isotope Labeling , Positron-Emission Tomography , RadiochemistryABSTRACT
BACKGROUND: The clinical severity of Sandhoff disease is known to vary widely. Furthermore, long-term follow-up report is very limited in the literature. CASE PRESENTATION: We present a long-term follow-up report of a patient with juvenile-onset Sandhoff disease with a motor neuron disease phenotype. The patient had compound heterozygous variants of HEXB (p.Trp460Arg, p. Arg533His); the Trp460Arg was a novel variant. Long-term follow-up revealed no intellectual deterioration, swallowing dysfunction, or respiratory muscle dysfunction despite progressive weakness of the extremities and sensory disturbances. CONCLUSION: We need to be aware of Sandhoff disease in patients with juvenile-onset motor neuron disease.
Subject(s)
Motor Neuron Disease/etiology , Sandhoff Disease/genetics , Adult , Age of Onset , Follow-Up Studies , Humans , Phenotype , Sandhoff Disease/complicationsABSTRACT
BACKGROUND: A 20-month-old Asian boy with normal growth presented with genu valgum, kyphosis, and pectus carinatum, with no neurological symptoms. No other symptoms suggestive of mucopolysaccharidoses, for example joint contracture and peculiar facies, were present. CASE PRESENTATION: As part of our differential diagnosis we found elevated urine glycosaminoglycans, which triggered further investigation. Detailed examination showed flattening of the ribs, kyphoscoliosis and ovalization of the thoracolumbar vertebral body, strikingly short metacarpals, and very slight cardiac regurgitation. N-Acetylgalactosamine-6-sulfatase levels in the blood and dermal fibroblasts were very low, thus confirming diagnosis of Morquio A within 2 months of presentation. The patient was placed on elosulfase alfa enzyme replacement therapy and followed for 3 years. CONCLUSIONS: This case exemplifies the importance of considering mucopolysaccharidoses as part of the initial differential diagnosis of pediatric patients with skeletal deformities; urine glycosaminoglycan levels and a blood enzyme mucopolysaccharidoses panel are simple screening tests that could lead to early definitive diagnosis.
Subject(s)
Mucopolysaccharidosis IV , Pectus Carinatum , Scoliosis , Child , Early Diagnosis , Enzyme Replacement Therapy , Humans , Infant , Male , Mucopolysaccharidosis IV/diagnosis , Mucopolysaccharidosis IV/drug therapyABSTRACT
BACKGROUND: Adverse drug events (ADEs) are a burden to the healthcare system. Preventable ADEs, which was ADEs due to medication errors, could be reduced if medication errors can be prevent or ameliorate. OBJECTIVE: We investigated the burden of preventable ADEs on the length of hospital stay (LOS) and costs, and estimated the national burden of preventable ADEs in pediatric inpatients in Japan. METHODS: We analyzed data from the Japan Adverse Drug Events (JADE) study on pediatric patients and estimated the incidence of preventable ADEs and associated extended LOS. Costs attributable to extended LOS by preventable ADEs were calculated using a national statistics database and we calculated the effect of preventable ADEs on national cost excess. RESULTS: We included 907 patients with 7377 patient-days. Among them, 31 patients (3.4%) experienced preventable ADEs during hospitalization. Preventable ADEs significantly increased the LOS by 14.1 days, adjusting for gender, age, ward, resident physician, surgery during hospitalization, cancer, and severe malformation at birth. The individual cost due to the extended LOS of 14.1 days was estimated as USD 8258. We calculated the annual extra expense for preventable ADEs in Japan as USD 329 676 760. Sensitivity analyses, considering the incidence of preventable ADEs and the length of hospital stay, showed that the expected range of annual extra expense for preventable ADEs in Japan is between USD 141 468 968 and 588 450 708. CONCLUSION: Preventable ADEs caused longer hospitalization and considerable extra healthcare costs in pediatric inpatients. Our results would encourage further efforts to prevent and ameliorate preventable ADEs.
ABSTRACT
Familial juvenile hyperuricemic nephropathy (FJHN) is a rare autosomal dominant disease caused by mutations in the uromodulin (UMOD) gene. It is characterized by the development of gout, tubulointerstitial nephropathy, and end-stage renal disease. Here we report a case of FJHN that was diagnosed in early childhood in a boy with a novel gene mutation. At the age of 4 years, the patient was admitted with a diagnosis of purpura nephritis. He was discharged following symptom alleviation. However, hyperuricemia (7-9 mg/dL) and mild renal dysfunction [creatinine-estimated glomerular filtration rate (eGFR): 80-90 mL/min/1.73 m2] persisted after discharge. FJHN was suspected on the basis of a maternal family history of hyperuricemia, renal dysfunction, and dialysis. Direct sequence analysis performed at the age of 5 years revealed a novel missense mutation (c766T > G), p.Cys256Gly, in exon 3. Urate-lowering therapy was started, which provided good uric acid control (6.0 mg/dL). At the age of 8 years, persistent renal dysfunction was observed (eGFR: 80-90 mL/min/1.73 m2). Interestingly, cases of FJHN with c744C > G (p.Cys248Trp) mutations also exhibit a high incidence of juvenile onset, and identical disulfide bridges are considered responsible for the accumulation of mutant UMOD in the endoplasmic reticulum. Pediatricians should consider UMOD mutation analysis for families with autosomal dominant tubulointerstitial kidney disease (ADTKD) and a bland urinary sediment, even if hyperuricemia is mild. Also, sex and genotype are very important prognostic factors for ADTKD caused by UMOD mutations.
Subject(s)
Hyperuricemia/diagnosis , Hyperuricemia/genetics , Child, Preschool , Humans , Male , MutationABSTRACT
The prevalence of Gaucher disease (GD) in Japan is much lower than that in Western countries; therefore, data on Japanese pediatric patients with GD type 1 are currently limited. The present study reports on the case of a Japanese pediatric patient with GD type 1 who was diagnosed when she presented with hepatosplenomegaly, thrombocytopenia and slight anemia at the age of 2 years. Serology tests revealed high levels of acid phosphatase (ACP) and angiotensin-converting enzyme (ACE). A bone marrow biopsy revealed the presence of Gaucher cells. Abdominal MRI indicated huge hepatosplenomegaly. Erlenmeyer flask deformity was observed on X-ray examination. MRI of the femora featured a high-intensity area within the diaphysis region. The enzymatic activity of leukocyte ß-glucosidase, the measurement of which is necessary for a definitive diagnosis of GD, had decreased to 186.7 nmol/h/mg (reference range, 1,424.0-2,338.0 nmol/h/mg). Based on these results, the patient was clinically diagnosed with GD. Glucocerebrosidase gene analysis identified the compound heterozygote mutation of F213I (c.754T>A) on exon 7 and L444P (c.1448T>C) on exon 11. Enzyme replacement therapy (ERT) along with an intravenous infusion of 60 U/kg of imiglucerase every other week was initiated following diagnosis. Hemoglobin levels and the platelet count gradually improved and normalized after two years. ACP and ACE levels, biomarkers of the progression of GD, also improved. Abdominal MRI at six months after the initiation of ERT revealed a decrease in the size of the liver and spleen, which normalized after 1 year. Conversely, MRI of the femora indicated no improvement in the high-intensity area within the diaphysis region for 10 years.