Development and evaluation of a patient-reported outcome measure specific for Gaucher disease with or without neurological symptoms in Japan

BACKGROUND

Patients with Gaucher disease (GD), a rare lysosomal storage disorder, have reduced health-related quality of life (HRQOL). A patient-reported outcome measure (PROM) for HRQOL developed for type 1 GD (GD1) is not appropriate for patients with neuronopathic GD (nGD) types 2 (GD2) and 3 (GD3). In this study, we developed a new PROM for use in all GD types. We previously reported the qualitative analysis of interviews with Japanese patients with nGD, which was used to create nGD-specific PROM items. Here we evaluated the full PROM combining the type 1 questionnaire with the new nGD-specific items.

METHODS

Patients with confirmed GD were recruited (Association of Gaucher Disease Patients in Japan or leading doctors) for pre-testing (May 2021) or the main survey (October-December 2021). The PROM had three parts: Parts 1 and 2 were translated into Japanese from the pre-existing GD1 PROM, whereas Part 3 was newly developed. Patients (or their caregivers, where necessary) completed the PROM questionnaire on paper and returned it by mail. Mean scores were determined overall and by GD type. Inter-item correlations, content consistency (Cronbach's alpha), and test-retest reliability (Cohen's kappa; main survey only, taken 2 weeks apart) were calculated.

RESULTS

Sixteen patients (three with GD1; six with GD2; seven with GD3) and 33 patients (nine with GD1; 13 with GD2; 11 with GD3) participated in the pre-test and main survey, respectively. All GD2 patients and one-third (6/18) of GD3 patients required caregivers to complete the questionnaire. Mean scores indicated that the burden was highest in GD2 and lowest in GD1. In the main survey, internal consistency was high (Cronbach's alpha = 0.898 overall, 0.916 for Part 3), and test-retest reliability was high for Part 3 (kappa > 0.60 for 13/16 items) but low for Part 1 (kappa < 0.60 for 12/15 items).

CONCLUSIONS

We have developed a flexible and reliable PROM that can be tailored for use in all types of GD and propose using Parts 1 and 2 for GD1, Parts 2 and 3 for GD2, and Parts 1, 2, and 3 for GD3.

Neonatal onset of Niemann-Pick disease type C in a patient with cholesterol re-accumulation in the transplanted liver and inflammatory bowel disease

BACKGROUND

Niemann-Pick disease type C (NPC) is an autosomal recessive inherited and neurodegenerative disorder. Approximately 10% of NPC patients have acute liver failure and sometimes need liver transplantation (LT), and 7% reportedly develop inflammatory bowel disease (IBD). We report the case of a girl with NPC who had a re- accumulation of cholesterol in the transplanted liver and NPC-related IBD.

CASE REPORT

The patient underwent living donor liver transplantation (LDLT) due to severe acute liver failure caused by an unknown etiology inherited from her father. At 1 year and 6 months (1Y6M), she developed neurological delay, catalepsy, and vertical supranuclear gaze palsy. The foam cells were found in her skin, and fibroblast Filipin staining was positive; hence, she was diagnosed with NPC. It was identified that her father had NPC heterozygous pathogenic variant. At 2 years, she had anal fissure, skin tag and diarrhea. She was diagnosed with NPC-related IBD, using a gastrointestinal endoscopy. Three years after LT, liver biopsy revealed foam cells and numerous fatty droplets. At 8 years, broken hepatocytes and substantial fibrosis were observed. She died from circulation failure due to hypoalbuminemia at 8Y2M.

CONCLUSIONS

In NPC, load of cholesterol metabolism is suggested to persist even after LT. LDLT from NPC heterozygous variant donor was insufficient to metabolize cholesterol overload. In NPC patients, the possibility of cholesterol re-accumulation should be considered when LT is performed. NPC-related IBD should be considered when NPC patients have anorectal lesions or diarrhea.

Burden of caregivers of patients with neuronopathic and non-neuronopathic Gaucher disease in Japan: A survey-based study

Background

Gaucher disease (GD), a rare lysosomal storage disorder, is associated with considerable patient and caregiver burden. We examined the applicability of existing caregiver questionnaires and assessed the level of burden in caregivers of patients with GD.

Methods

This cross-sectional, non-interventional study was conducted in Japan. Caregivers of patients with confirmed GD (any type) were recruited (patient association group and referral) for pre-testing (May 2021) or the main survey (October-December 2021). Caregivers completed the Caregiver Impact Questionnaire (CIQ; 30 items) and Zarit Caregiver Burden Interview (ZBI; 22 items) on paper. Total CIQ and ZBI scores and subscores were determined overall and by GD type. Inter-item correlations and test-retest reliability (2 rounds, 2 weeks apart) were calculated. The relationship between caregiving duration and caregiver burden was also analyzed.

Results

Nine caregivers (type 2 [GD2]: n = 6; type 3 [GD3]: n = 3) and 25 caregivers (type 1 [GD1]: n = 2; GD2: n = 17; GD3: n = 6) completed the pre-test and main survey, respectively. In the main survey, mean total CIQ score, all CIQ subscores (except emotional function), and total ZBI score were highest in caregivers of patients with GD2 compared with caregivers of patients with GD1/GD3. High test-retest reliability (Kappa >0.6) was observed for 15 CIQ items and 16 ZBI items. CIQ and ZBI scores appeared to be positively correlated with each other and negatively correlated with caregiving duration.

Conclusions

The CIQ and ZBI are applicable, reliable measures to assess burden in caregivers of patients with GD in Japan. Caregiver burden was highest in caregivers of patients with GD2 and decreased with caregiving duration.

Qualitative analysis of patient interviews on the burden of neuronopathic Gaucher disease in Japan

BACKGROUND

Gaucher disease (GD) is a rare, autosomal recessive lysosomal storage disorder that adversely affects life expectancy and health-related quality of life (HRQOL). Although HRQOL questionnaires are available for type 1 GD, they are not suitable for patients with the neuronopathic types 2 and 3 GD who have neurological symptoms that develop during early childhood or adolescence. Here we report the development of a language-validated HRQOL questionnaire specifically for patients with neuronopathic types 2 and 3 GD in Japan, which is the first step toward HRQOL questionnaire provision for all types of GD in the future.

METHODS

In February and March 2021, semi-structured interviews were conducted by the authors (supported by qualified interviewers) with patients and/or their caregivers (for patients < 16 years old) who were recruited from a Japanese patient association, the Association of Gaucher Disease Patients in Japan. Qualitative analysis of interview transcripts was used to identify major themes and key topics within those themes. Hierarchical cluster analysis and co-occurrence network analysis were performed to map relationships between commonly occurring words. The study is registered at the UMIN Clinical Trials Registry ( https://www.umin.ac.jp/ctr/index.htm [UMIN000042872]).

RESULTS

Three main themes emerged from qualitative analysis: treatment status, patient burden, and social support systems. Key topics within each theme included hearing impairment, visual impairment, difficulty swallowing, difficulty speaking, involuntary movement of extremities, epileptic seizures, and body aches (treatment status); anxiety about symptoms, difficulty with exercise and work, anxiety about continuing treatment, anxiety about going out, and tiredness from hospital visit or treatment (patient burden); and dissatisfaction about government service, lack of social support, and information exchange in the patient association (social support systems). Commonly used words and the relationships between words identified through the hierarchical cluster and co-occurrence network analyses supported these themes and topics.

CONCLUSIONS

The themes and topics identified in this analysis were specific to patients with types 2 and 3 GD and will be used to inform the development of a HRQOL questionnaire specifically for patients with all GD types.

Relationship between the housing coldness/warmth evaluation by CASBEE Housing Health Checklist and psychological distress based on TMM Community-Based Cohort Study: a cross-sectional analysis

OBJECTIVES

Previous studies have reported the relationship between housing environment and health, although due to cost and effort, it was difficult to conduct housing condition surveys on a large scale. The CASBEE Housing Health Checklist (the Checklist) made it possible to easily evaluate the housing condition from the resident's perspective. This study examined the relationship between housing coldness/warmth evaluation using the Checklist and psychological distress in a large-scale general Japanese population.

STUDY DESIGN

A cross-sectional study.

METHODS

We analysed data from 29,380 people aged ≥20 years who lived in Miyagi Prefecture, Japan. As an assessment of housing coldness/warmth, we used the Checklist. We classified participants' total scores on the Checklist related to coldness/warmth into quartiles. The Kessler 6 scale was used as an indicator of psychological distress. Multivariable logistic regression models were used to estimate the adjusted odds ratio (OR) and 95% confidence intervals (CIs). Adjusted OR and P-values for linear trends were calculated using the quartiles of the Checklists' score.

RESULTS

Among participants in Q1 (i.e., poorer subjective house condition), the percentage of people with psychological distress was high. Compared to the highest quartile, Q1 showed poorer evaluation of housing coldness/warmth, and higher OR for psychological distress. The OR (95% CI) of psychological distress for Q3, Q2, and Q1 compared with Q4 were 1.93 (1.74-2.14), 2.82 (2.55-3.12), and 5.78 (5.25-6.35), respectively.

CONCLUSIONS

Housing coldness/warmth evaluation was significantly related to psychological distress. This finding suggests that maintaining a comfortable thermal environment at home could be important for residents' mental health.

Long-term efficacy of low-dose perampanel for progressive myoclonus epilepsy in a patient with Gaucher disease type 3

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.

Prevalence of patients with lysosomal storage disorders and peroxisomal disorders: A nationwide survey in Japan

INTRODUCTION

Lysosomal storage disorders and peroxisomal disorders are rare diseases caused by the accumulation of substrates of the metabolic pathway within lysosomes and peroxisomes, respectively. Owing to the rarity of these diseases, the prevalence of lysosomal storage disorders and peroxisomal disorders in Japan is unknown. Therefore, we conducted a nationwide survey to estimate the number of patients with lysosomal storage disorders and peroxisomal disorders in Japan.

METHODS

A nationwide survey was conducted following the "Manual of nationwide epidemiological survey for understanding patient number and clinical epidemiology of rare diseases (3rd version)". A questionnaire asking for detailed information, such as disease phenotypes and medical history, was created and sent to 504 institutions with doctors who have experience in treating patients with lysosomal storage disorders and peroxisomal disorders. Result A total of 303 completed questionnaires were collected from 504 institutions (response rate: 60.1%). The number of patients was estimated by calculating the rate/frequency of overlap. The estimated number of patients was 1658 (±264.8) for Fabry disease, 72 (±11.3) for mucopolysaccharidosis I, 275 (±49.9) for mucopolysaccharidosis II, 211 (±31.3) for Gaucher disease, 124 (±25.8) for Pompe disease, 83 (±44.3) for metachromatic leukodystrophy, 57 (±9.4) for Niemann-Pick type C, and 262 (±42.3) for adrenoleukodystrophy. In addition the birth prevalence was calculated using the estimated number of patients and birth year data for each disease, and was 1.25 for Fabry disease, 0.09 for mucopolysaccharidosis I, 0.38 for mucopolysaccharidosis II, 0.19 for Gaucher disease, 0.14 for Pompe disease, 0.16 for metachromatic leukodystrophy, 0.16 for Niemann-Pick type C, and 0.20 for adrenoleukodystrophy.

DISCUSSION

Among the diseases analyzed, the disease with the highest prevalence was Fabry disease, followed by mucopolysaccharidosis II, adrenoleukodystrophy, Gaucher disease and metachromatic leukodystrophy. In particular, the high prevalence of mucopolysaccharidosis II and Gaucher disease type II was a feature characteristic of Japan.

CONCLUSION

We estimated the number of patients with lysosomal storage disorders and peroxisomal disorders in Japan. The details of the age at diagnosis and treatment methods for each disease were clarified, and will be useful for the early diagnosis of these patients and to provide appropriate treatments. Furthermore, our results suggest that supportive care and the development of an environment that can provide optimal medical care is important in the future.

The definition of neuronopathic Gaucher disease

Neuronopathic Gaucher disease (nGD) has a very wide clinical and genotypic spectrum. However, there is no consensus definition of nGD, including no description of how best to diagnostically separate the acute form-Gaucher type 2-from the subacute or chronic form-Gaucher type 3. In this article, we define the various forms of Gaucher disease with particular emphasis on the presence of gaze palsy in all patients with nGD. This consensus definition will help in both clinical diagnosis and appropriate patient recruitment to upcoming clinical trials.

Development of a Diagnostic Screening Strategy for Niemann-Pick Diseases Based on Simultaneous Liquid Chromatography-Tandem Mass Spectrometry Analyses of N-Palmitoyl-O-phosphocholine-serine and Sphingosylphosphorylcholine

Early diagnosis of Niemann-Pick diseases (NPDs) is important for better prognosis of such diseases. N-Palmitoyl-O-phosphocholine-serine (PPCS) is a new NPD biomarker possessing high sensitivity, and with its combination with sphingosylphosphocholine (SPC) it may be possible to distinguish NPD-C from NPD-A/B. In this study, a rapid liquid chromatography-tandem mass spectrometry (LC-MS/MS) method (method 1) and a validated LC-MS/MS analysis (method 2) of PPCS and SPC were developed, and we have proposed a diagnostic screening strategy for NPDs using a combination of serum PPCS and SPC concentrations. Nexera and API 5000 were used as LC-MS/MS systems. C18 columns with lengths of 10 and 50 mm were used for method 1 and 2, respectively. ²H₃-Labeled PPCS and nor-SPC were used as internal standards. Selective reaction monitoring in positive-ion mode was used for MS/MS. Run times of 1.2 and 8 min were set for methods 1 and 2, respectively. In both methods 1 and 2, two analytes showed high linearity in the range of 1-4000 ng/mL. Method 2 provided high accuracy and precision in method validation. Serum concentrations of both analytes were significantly higher in NPD-C patients than those of healthy subjects in both methods. Serum PPCS correlated between methods 1 and 2; however, it was different in the case of SPC. The serum PPCS/SPC ratio was different in healthy subjects, NPD-C, and NPD-A/B. These results suggest that using a combination of the two LC-MS/MS analytical methods for PPCS and SPC is useful for diagnostic screening of NPDs.

AB1198 DECREASING OF TOTAL AND UNILATERAL KNEE ARTHROPLASTIES DUE TO RHEUMATOID ARTHRITIS BUT INCREASING IN OSTEOARTHRITIS IN OUR INSTITUTES IN LAST DECADE OF SUPER-AGING SOCIETY

Background:

The rate of elderly people over 65 year-old increased from 22.1 % in 2008 to 27.7% in 2017 in Japan, also from 27.1 % to 32.3 % in our super-aging area1, 2. The number of total and unilateral knee arthroplasty (TKA, UKA) have increased annually in all over the world according to the larger population of elderly people due to osteoarthritis (OA)3. In fact, the numbers of primary TKA predicted increasing from six hundred fifty-six thousand cases at 2010 to one million three hundred seventy-six thousand cases at 2020 in USA4. In the other hand, rheumatoid arthritis (RA) therapy have been remarkably improved from starting to use biologic agents since 2003 in Japan5. The rate of orthopaedic surgery may reflect trends in disease severity and drug management of RA5.

Objectives:

The aim of study is to reveal the rate of TKA, including UKA and revision TKA in elderly people in our super-aging area of Japan.

Methods:

We surveyed the number and cause of primary and revision TKA and UKA in our institutes using the data of diagnosis procedure combination and the record of surgeries in the last decade.

Results:

Figure 1.

Table 1.2008-122013-17TimesOsteoarthritis15652252*1.3Rheumatoid arthritis13181*0.6Trauma155Osteonecrosis of femoral condylar2041*2.1Revision21391.9Total17382418*1.4*p< 0.05

Conclusion:

The number and rate of primary TKA/UKA due to RA decreased year by year because of progression of modern medication therapy. In the other hand, in case of OA increased because of increasing of elderly people affected by knee OA in the super-aging society.

References:

[1]National Institute of Population and Social Security Research. Japanese Mortality Database, 2018.http://www.ipss.go.jp/

[2]Yamagata prefecture, Health and longevity Promotion Section. Rate of elderly people in Yamagata prefecture, 2018.http://www.pref.yamagata.jp/ou/kikakushinko/020052/tokei/jinkel.html

[3]Annual report 2017 of replacement arthroplasty in Japan. The Japanese Society For Replacement Arthroplasty The Japan Arthroplasty Register.https://jsra.info/jar-report.html

[4]Kurtz SM, et al. J Bone Joint Surg Am. 96: 624-30, 2014.

[5]Momohara S, et al. J Rheumatol. 41:862-5, 2014.

Disclosure of Interests:

None declared

The Lotus japonicus nucleoporin GLE1 is involved in symbiotic association with rhizobia

Nucleoporins are components of the nuclear pore complexes, channels that regulate the transport of macromolecules between the nucleus and cytoplasm. The nucleoporin GLE1 (GLFG lethal1) functions in the export of messenger RNAs containing poly(A) tails from the nucleus into the cytoplasm. Here we investigated a mutant of the model legume Lotus japonicus that was defective in GLE1, which we designated Ljgle1. The growth of Ljgle1 was retarded under symbiotic association with rhizobia, and the nitrogen-fixation activities of the nodules were around one-third of those in the wild-type plant. The growth of Ljgle1 was not substantialy recovered by supplemention of combined nitrogen. Nodules formed on the Ljgle1 were smaller than those on the wild-type and colored faint pink. The numbers of infected cells of nodules on the Ljgle1 were smaller than on the wild-type plant, and the former cells remained undeveloped. Rhizobia in the cells of the Ljgle1 exhibited disordered forms, and the symbiosome membrane was closely attached to the bacterial membrane. These results indicate that GLE1 plays a distinct role in the symbiotic association between legumes and rhizobia.

Presenting signs and patient co-variables in Gaucher disease: outcome of the Gaucher Earlier Diagnosis Consensus (GED-C) Delphi initiative

Background

Gaucher disease (GD) presents with a range of signs and symptoms. Physicians can fail to recognise the early stages of GD owing to a lack of disease awareness, which can lead to significant diagnostic delays and sometimes irreversible but avoidable morbidities.

Aim

The Gaucher Earlier Diagnosis Consensus (GED‐C) initiative aimed to identify signs and co‐variables considered most indicative of early type 1 and type 3 GD, to help non‐specialists identify ‘at‐risk’ patients who may benefit from diagnostic testing.

Methods

An anonymous, three‐round Delphi consensus process was deployed among a global panel of 22 specialists in GD (median experience 17.5 years, collectively managing almost 3000 patients). The rounds entailed data gathering, then importance ranking and establishment of consensus, using 5‐point Likert scales and scoring thresholds defined a priori.

Results

For type 1 disease, seven major signs (splenomegaly, thrombocytopenia, bone‐related manifestations, anaemia, hyperferritinaemia, hepatomegaly and gammopathy) and two major co‐variables (family history of GD and Ashkenazi‐Jewish ancestry) were identified. For type 3 disease, nine major signs (splenomegaly, oculomotor disturbances, thrombocytopenia, epilepsy, anaemia, hepatomegaly, bone pain, motor disturbances and kyphosis) and one major co‐variable (family history of GD) were identified. Lack of disease awareness, overlooking mild early signs and failure to consider GD as a diagnostic differential were considered major barriers to early diagnosis.

Conclusion

The signs and co‐variables identified in the GED‐C initiative as potentially indicative of early GD will help to guide non‐specialists and raise their index of suspicion in identifying patients potentially suitable for diagnostic testing for GD.

High-frequency component in flash visual evoked potentials in type 3 Gaucher disease

OBJECTIVE

To characterize the visual evoked potentials (VEP) in patients with type 3 Gaucher disease (GD) with or without progressive myoclonus epilepsy.

METHODS

Three young adults with progressive myoclonus epilepsy (type 3a GD) and two children without progressive myoclonus epilepsy (type 3b GD) were enrolled. Flash visual and somatosensory evoked potentials (F-VEP and SEP, respectively) were retrospectively reviewed in all patients under enzyme replacement therapy. Pattern reversal visual evoked potentials (PR-VEP) were recorded in the type 3a group.

RESULT

High-frequency components were provoked at early latencies on averaged F-VEP in all patients with type 3a and one patient with type 3b GD. Conversely, no activities were recorded in PR-VEP. The onset latency of the components began at 15.3-19.8 ms after flash stimulation. Four-five of the F-VEP examination the activities' duration overrode the N75 waveforms and were prolonged toward the P100 peak latency. The F-VEP amplitude did not differ between the type 3a and type 3b groups, while the SEP amplitude was higher in the type 3a than in the type 3b group.

SIGNIFICANCE

High-frequency components on F-VEP using bandpass filter at 10-200 Hz may help assess augmented excitability in the visual cortex of type 3 GD patients.

Structural Determination of Lysosphingomyelin-509 and Discovery of Novel Class Lipids from Patients with Niemann-Pick Disease Type C

Niemann-Pick disease type C (NPC) is an autosomal recessive disorder caused by the mutation of cholesterol-transporting proteins. In addition, early treatment is important for good prognosis of this disease because of the progressive neurodegeneration. However, the diagnosis of this disease is difficult due to a variety of clinical spectrum. Lysosphingomyelin-509, which is one of the most useful biomarkers for NPC, was applied for the rapid and easy detection of NPC. The fact that its chemical structure was unknown until recently implicates the unrevealed pathophysiology and molecular mechanisms of NPC. In this study, we aimed to elucidate the structure of lysosphingomyelin-509 by various mass spectrometric techniques. As our identification strategy, we adopted analytical and organic chemistry approaches to the serum of patients with NPC. Chemical derivatization and hydrogen abstraction dissociation-tandem mass spectrometry were used for the determination of function groups and partial structure, respectively. As a result, we revealed the exact structure of lysosphingomyelin-509 as N-acylated and O-phosphocholine adducted serine. Additionally, we found that a group of metabolites with N-acyl groups were increased considerably in the serum/plasma of patients with NPC as compared to that of other groups using targeted lipidomics analysis. Our techniques were useful for the identification of lysosphingomyelin-509.

Investigation of diagnostic performance of five urinary cholesterol metabolites for Niemann-Pick disease type C

Niemann-Pick disease type C (NPC) is an autosomal recessive disorder characterized by progressive nervous degeneration. Because of the diversity of clinical symptoms and onset age, the diagnosis of this disease is difficult. Therefore, biomarker tests have attracted significant attention for earlier diagnostics. In this study, we developed a simultaneous analysis method for five urinary conjugated cholesterol metabolites, which are potential diagnostic biomarkers for a rapid, convenient, and noninvasive chemical diagnosis, using LC/MS/MS. By the method, their urinary concentrations were quantified and the NPC diagnostic performances were evaluated. The developed LC/MS/MS method showed high accuracy and satisfied all analytical method validation criteria. When the urine of healthy controls and patients with NPC was analyzed, three of five urinary conjugated cholesterol metabolite concentrations corrected by urinary creatinine were significantly higher in the patients with NPC. As a result of receiver operating characteristics analysis, these urinary metabolites might have excellent diagnostic marker performance. 3β-Sulfooxy-7β-hydroxy-5-cholenoic acid showed particularly excellent diagnostic performance with both 100% clinical sensitivity and specificity, suggesting that it is a useful NPC diagnostic marker. The urinary conjugated cholesterol metabolites exhibited high NPC diagnostic marker performance and could be used for NPC diagnosis.

Surface-Specific Spectroscopy of Water at a Potentiostatically Controlled Supported Graphene Monolayer

Knowledge of the structure of interfacial water molecules at electrified solid materials is the first step toward a better understanding of important processes at such surfaces, in, e.g., electrochemistry, atmospheric chemistry, and membrane biophysics. As graphene is an interesting material with multiple potential applications such as in transistors or sensors, we specifically investigate the graphene-water interface. We use sum-frequency generation spectroscopy to investigate the pH- and potential-dependence of the interfacial water structure in contact with a chemical vapor deposited (CVD) grown graphene surface. Our results show that the SFG signal from the interfacial water molecules at the graphene layer is dominated by the underlying substrate and that there are water molecules between the graphene and the (hydrophilic) supporting substrate.

Effect of Ambroxol chaperone therapy on Glucosylsphingosine (Lyso-Gb1) levels in two Canadian patients with type 3 Gaucher disease

Type 3 Gaucher disease (GD3) is characterized by progressive neurological features in addition to the typical systemic manifestations. Enzyme replacement therapy (ERT), the main stay treatment for Gaucher disease (GD), is not efficacious for the neurological manifestations. Ambroxol, in combination with ERT has been suggested to have potential as a promising therapy for patients with GD3. The purpose of this study is to assess the effect of Ambroxol on glucosylsphingosine (Lyso-Gb1) levels, and on the neurological morbidity, in two Canadian patients with GD3.

A case of Niemann-Pick disease type C with neonatal liver failure initially diagnosed as neonatal hemochromatosis

BACKGROUND

Niemann-Pick type C (NPC) is a lysosomal lipid storage disease with mutation of NPC1/NPC2 genes, which transport lipids in the endosome and lysosome, and various neurological symptoms. NPC patients also develop hepatosplenomegaly or liver disorder in the neonatal period, and 10% suffer severe liver failure. Neonatal hemochromatosis (NH) is a liver disorder characterized by hepatic and extrahepatic siderosis. Although the etiology of NH is unclear, recent reports suggest that the gestational alloimmune mechanism is the cause of NH. Herein, we report a Japanese NPC patient initially diagnosed as NH.

CASE REPORT

A 5-day-old boy was transferred to our hospital with severe cholestatic liver failure. Congenital infections and metabolic screening were negative, and NH was suspected. However intra and extrahepatic siderosis were not found. As his liver deteriorated rapidly, liver transplantation was performed at 19 days old. The explanted liver showed cirrhosis, and strong C5b-9 complex staining of hepatocytes, so NH was diagnosed. From the age of one and a half years, he developed regression, vertical supranuclear gaze palsy and cataplexy. Fibroblast filipin staining was strong, blood oxysterol was high, and there were compound heterozygous mutations in NPC1,p.[(F288L)];[(K1206N)]. The patient was then diagnosed as NPC and started on miglustat.

CONCLUSION

Neonatal liver failure was initially diagnosed as NH. Later, the patient developed various neurological symptoms characteristic of NPC. Neurological follow-up of children who develop NH is required.

Elevation of plasma lysosphingomyelin-509 and urinary bile acid metabolite in Niemann-Pick disease type C-affected individuals

Niemann-Pick disease type C (NPC) is a neurovisceral disorder associated with the accumulation of lipids such as cholesterol and sphingolipids. NPC is caused by either NPC1 or NPC2, which encode lysosomal proteins located at membraneous and soluble fractions, respectively. For the past decade, the oxidation products of cholesterol, such as cholestane-3β,5α,6β-triol and 7-ketocholesterol, have been considered selective biomarkers for NPC. However, recent evidence has indicated numerous novel biomarkers for NPC, which raises the possibility that the diagnosis of NPC might be associated with the elevation of multiple lipid biomarkers, rather than a single biomarker. Sphingosylphosphorylcholine (SPC) has been suggested to be one such biomarker for NPC, in which elevated sphingomyelin is a potential precursor. Thus, we first performed a validation study of plasma SPC using LC-MS/MS. The results showed the following plasma concentrations in the NPC-affected and control individuals, respectively: 8.2 ± 2.8 nM (mean ± SD; median, 7.0 nM; max, 11.7 nM; min, 5.1 nM; n = 5) and 3.1 ± 1.4 nM (median, 2.9 nM; max, 4.8 nM; min, 1.5 nM; n = 7). We further extended the study to plasma lysophingomyelin-509 for NPC, a newly reported biomarker with uncharacterized chemical nature. Based on these result with plasma SPC as a surrogate marker, the value of mean of median of plasma lysophingomyelin-509 in NPC-affected individuals elevated at 65.2 (max, 73.2; min, 26.7; n = 5). Furthermore, the efficacy of plasma SPC and lysosphingomyelin-509 as promising biomarkers for this disorder was supported by the finding that the urinary concentration of 3β-sulfooxy-7β-N-acetylglucosaminyl-5-cholen-24-oic acid, an established biomarker for NPC, was also elevated in the NPC-affected individuals. These results suggest that a novel combination of plasma biomarkers, such as SPC and/or lysophingomyelin-509, and urinary bile acid metabolite could offer a promising platform for the diagnosis of NPC.

[Clinical characteristics of early juvenile GM2 gangliosidosis: a case report]

We describe the case of a 15-year-old male with early juvenile type GM2 gangliosidosis. He first manifested with progressive clumsiness in his extremities at the age of 1.5 years, followed by motor regression. Intellectual disability became evident as late as age 6 years. This discrepancy along with rapid motor deterioration after varicella infection, lack of startle response or macrocephaly, and paucity of myoclonus were thought to be characteristic of juvenile GM2 gangliosidosis. In contrast to the cerebellar atrophy as the initial finding in usual juvenile GM2 gangliosidosis, magnetic resonance imaging revealed initially cerebral, and subsequently cerebellar, progressive atrophy. Autistic behavioral problems, including phonophobia, during intellectual regression in this patient was also unusual in juvenile GM2 gangliosidosis. Thus, recognition of these features would prompt proper diagnosis and insights into the pathomechanisms of GM2 gangliosidosis.

Selective Spinal Fusion for Neuromuscular Scoliosis in a Patient with Pompe Disease: A Case Report and Review of the Literature

CASE

A 16-year-old girl with Pompe disease underwent surgery for scoliosis. She had been able to walk without any assistance, and kept her balance by swinging her waist. Therefore, we performed posterior selective spinal correction and fusion to avoid any adverse effects on walking ability that could occur with immobilization of the lumbosacral spine. After surgery, she was highly satisfied with her ability to perform the activities of daily living.

CONCLUSION

For nonambulatory patients with scoliosis and Pompe disease, long fusion from the upper thoracic spine to the pelvis is generally required. However, in ambulatory patients, in order to maintain the ability to walk, selective spinal fusion is an alternative.

Brain pericytes serve as microglia-generating multipotent vascular stem cells following ischemic stroke

Background

Microglia are the resident macrophage population of the central nervous system (CNS) and play essential roles, particularly in inflammation-mediated pathological conditions such as ischemic stroke. Increasing evidence shows that the population of vascular cells located around the blood vessels, rather than circulating cells, harbor stem cells and that these resident vascular stem cells (VSCs) are the likely source of some microglia. However, the precise traits and origins of these cells under pathological CNS conditions remain unclear.

Methods

In this study, we used a mouse model of cerebral infarction to investigate whether reactive pericytes (PCs) acquire microglia-producing VSC activity following ischemia.

Results

We demonstrated the localization of ionized calcium-binding adaptor molecule 1 (Iba1)-expressing microglia to perivascular regions within ischemic areas. These cells expressed platelet-derived growth factor receptor-β (PDGFRβ), a hallmark of vascular PCs. PDGFRβ⁺ PCs isolated from ischemic, but not non-ischemic, areas expressed stem/undifferentiated cell markers and subsequently differentiated into various cell types, including microglia-like cells with phagocytic capacity.

Conclusions

The study results suggest that vascular PCs acquire multipotent VSC activity under pathological conditions and may thus be a novel source of microglia.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-016-0523-9) contains supplementary material, which is available to authorized users.

Ambroxol chaperone therapy for neuronopathic Gaucher disease: A pilot study

Objective

Gaucher disease (GD) is a lysosomal storage disease characterized by a deficiency of glucocerebrosidase. Although enzyme‐replacement and substrate‐reduction therapies are available, their efficacies in treating the neurological manifestations of GD are negligible. Pharmacological chaperone therapy is hypothesized to offer a new strategy for treating the neurological manifestations of this disease. Specifically, ambroxol, a commonly used expectorant, has been proposed as a candidate pharmacological chaperone. The purpose of this study was to evaluate the safety, tolerability, and neurological efficacy of ambroxol in patients with neuronopathic GD.

Methods

This open‐label pilot study included five patients who received high‐dose oral ambroxol in combination with enzyme replacement therapy. Safety was assessed by adverse event query, physical examination, electrocardiography, laboratory studies, and drug concentration. Biochemical efficacy was assessed through evidence of glucocerebrosidase activity in the lymphocytes and glucosylsphingosine levels in the cerebrospinal fluid. Neurological efficacy was evaluated using the Unified Myoclonus Rating Scale, Gross Motor Function Measure, Functional Independence Measure, seizure frequency, pupillary light reflex, horizontal saccadic latency, and electrophysiologic studies.

Results

High‐dose oral ambroxol had good safety and tolerability, significantly increased lymphocyte glucocerebrosidase activity, permeated the blood–brain barrier, and decreased glucosylsphingosine levels in the cerebrospinal fluid. Myoclonus, seizures, and pupillary light reflex dysfunction markedly improved in all patients. Relief from myoclonus led to impressive recovery of gross motor function in two patients, allowing them to walk again.

Interpretation

Pharmacological chaperone therapy with high‐dose oral ambroxol shows promise in treating neuronopathic GD, necessitating further clinical trials.

Real-time observation of irradiated HeLa-cell modified by fluorescent ubiquitination-based cell-cycle indicator using synchrotron X-ray microbeam

Fluorescent ubiquitination-based cell-cycle indicator (FUCCI) human cancer (HeLa) cells (red indicates G1; green, S/G2) were exposed to a synchrotron X-ray microbeam. Cells in either G1 or S/G2 were irradiated selectively according to their colour in the same microscopic field. Time-lapse micrographs of the irradiated cells were acquired for 24 h after irradiation. For fluorescent immunostaining, phosphorylated histone proteins (γ-H2AX) indicated the induction of DNA double-strand breaks. The cell cycle was arrested by irradiation at S/G2. In contrast, cells irradiated at G1 progressed to S/G2. The foci were induced in cells irradiated at both G1 and S/G2, suggesting that the G1-S (or S) checkpoint pathway does not function in HeLa cells due to the fact that the cells are functionally p53 deficient, even though X-ray microbeam irradiation significantly induces double-strand breaks. These results demonstrate that single FUCCI cell exposure and live cell imaging are powerful methods for studying the effects of radiation on the cell cycle.

Visualisation of cell cycle modifications by X-ray irradiation of single HeLa cells using fluorescent ubiquitination-based cell cycle indicators

To explore the effects of X-ray irradiation on mammalian cell cycle dynamics, single cells using the fluorescent ubiquitination-based cell cycle indicator (Fucci) technique were tracked. HeLa cells expressing Fucci were used to visualise cell cycle modifications induced by irradiation. After cultured HeLa-Fucci cells were exposed to 5 Gy X-rays, fluorescent cell images were captured every 20 min for 48 h using a fluorescent microscope. Time dependence of the fluorescence intensity of S/G2 cells was analysed to examine the cell cycle dynamics of irradiated and non-irradiated control cells. The results showed that irradiated cells could be divided into two populations: one with similar cell cycle dynamics to that of non-irradiated cells, and another displaying a prolonged G2 phase. Based on these findings, it is proposed in this article that an underlying switch mechanism is involved in cell cycle regulation and the G2/M checkpoint of HeLa cells.

Live-cell imaging study of mitochondrial morphology in mammalian cells exposed to X-rays

Morphological changes in mitochondria induced by X-irradiation in normal murine mammary gland cells were studied with a live-cell microscopic imaging technique. Mitochondria were visualised by staining with a specific fluorescent probe in the cells, which express fluorescent ubiquitination-based cell-cycle indicator 2 (Fucci2) probes to visualise cell cycle. In unirradiated cells, the number of cells with fragmented mitochondria was about 20 % of the total cells through observation period (96 h). In irradiated cells, the population with fragmented mitochondria significantly increased depending on the absorbed dose. Particularly, for 8 Gy irradiation, the accumulation of fragmentation persists even in the cells whose cell cycle came to a stand (80 % in G1 (G0-like) phase). The fraction reached to a maximum at 96 h after irradiation. The kinetics of the fraction with fragmented mitochondria was similar to that for cells in S/G2/M phase (20 %) through the observation period (120 h). The evidences show that, in irradiated cells, some signals are continually released from a nucleus or cytoplasm even in the G0-like cells to operate some sort of protein machineries involved in mitochondrial fission. It is inferred that this delayed mitochondrial fragmentation is strongly related to their dysfunction, and hence might modulate radiobiological effects such as mutation or cell death.

Tuning the deposition of molecular graphene nanoribbons by surface functionalization

We show that individual, isolated graphene nanoribbons, created with a molecular synthetic approach, can be assembled on functionalised wafer surfaces treated with silanes. The use of surface groups with different hydrophobicities allows tuning the density of the ribbons and assessing the products of the polymerisation process.

pH-Responsive Pharmacological Chaperones for Rescuing Mutant Glycosidases

A general approach is reported for the design of small-molecule competitive inhibitors of lysosomal glycosidases programmed to 1) promote correct folding of mutant enzymes at the endoplasmic reticulum, 2) facilitate trafficking, and 3) undergo dissociation and self-inactivation at the lysosome. The strategy is based on the incorporation of an orthoester segment into iminosugar conjugates to switch the nature of the aglycone moiety from hydrophobic to hydrophilic in the pH 7 to pH 5 window, which has a dramatic effect on the enzyme binding affinity. As a proof of concept, new highly pH-responsive glycomimetics targeting human glucocerebrosidase or α-galactosidase with strong potential as pharmacological chaperones for Gaucher or Fabry disease, respectively, were developed.

Effect of levetiracetam in acute encephalitis with refractory, repetitive partial seizures during acute and chronic phase

AIM

To clarify the effect of levetiracetam (LEV) for acute and chronic seizure control in acute encephalitis with refractory, repetitive partial seizures (AERRPS).

METHODS

We retrospectively reviewed the clinical course of six AERRPS cases treated with LEV, and explored the acute phase termination by withdrawal from barbiturate-induced coma under artificial ventilation, and the reduction in seizure frequency during the chronic phase. LEV was administrated orally or via nasogastric tubes as an add-on agent during acute (n=3; age 8-10 years) and chronic (n=3; age 19-30 years) AERRPS.

RESULTS

In the acute phase, administration of LEV (50-60 mg/kg/d) in combination with phenobarbital (n=3; peak 57.9-76.1 μg/ml) and potassium bromide (n=2; 30-36 mg/kg/d)) resulted in successful reduction of intravenous barbiturate dosage and withdrawal from artificial ventilation. In the chronic phase, seizure frequency reduced by >75% for 5-18 months with LEV 750-1500 mg/d.

CONCLUSION

LEV may affect seizure control in AERRPS, particularly during the chronic phase, through its unique action of inhibition of excitatory neurotransmitter release. The regimen of oral barbiturate, potassium bromide and LEV would be worth for trial during the acute phase of AERRPS.

Strict actions of the human wrist flexors: A study with an electrical neuromuscular stimulation method

In order to elucidate strict actions of the human wrist flexors, motion and force produced by electrical neuromuscular stimulation (ENS) to each of musculus (m.) flexsor carpi radialis (FCR) and m. flexsor carpi ulnaris (FCU) with the prone, semiprone, and supine forearm were studied in ten healthy human subjects. Abduction, extension, adduction, and flexion directions were represented by, respectively, 0°, 90°, 180°, and 270°. ENS to FCR and FCU produced motion in direction of, respectively, 273° (mean) and 265° with the prone, 249° and 232° with the semiprone, and 242° and 229° with the supine forearm to the maximal range. Direction/strength (Nm) of force by ENS to FCR and FCU were, respectively, 298°/1.16 and 239°/1.70 with the prone, 279°/1.30 and 241°/1.62 with the semiprone, and 267°/1.24 and 227°/2.04 with the supine forearm. ENS to FCR exhibited force of 20-29% of maximal flexion and 7-15% of maximal abduction or 1-4% of maximal adduction and that to FCU force of 24-28% of maximal flexion and 15-25% of maximal adduction. The force study results suggest that FCU is a flexor rather than an adductor with every forearm position. FCR should be a flexor rather than an abductor with the prone and semiprone and a flexor with the supine forearm. The action of FCR as the abductor should diminish with supinating the forearm.

Brain vascular pericytes following ischemia have multipotential stem cell activity to differentiate into neural and vascular lineage cells

Brain vascular pericytes (PCs) are a key component of the blood-brain barrier (BBB)/neurovascular unit, along with neural and endothelial cells. Besides their crucial role in maintaining the BBB, increasing evidence shows that PCs have multipotential stem cell activity. However, their multipotency has not been considered in the pathological brain, such as after an ischemic stroke. Here, we examined whether brain vascular PCs following ischemia (iPCs) have multipotential stem cell activity and differentiate into neural and vascular lineage cells to reconstruct the BBB/neurovascular unit. Using PCs extracted from ischemic regions (iPCs) from mouse brains and human brain PCs cultured under oxygen/glucose deprivation, we show that PCs developed stemness presumably through reprogramming. The iPCs revealed a complex phenotype of angioblasts, in addition to their original mesenchymal properties, and multidifferentiated into cells from both a neural and vascular lineage. These data indicate that under ischemic/hypoxic conditions, PCs can acquire multipotential stem cell activity and can differentiate into major components of the BBB/neurovascular unit. Thus, these findings support the novel concept that iPCs can contribute to both neurogenesis and vasculogenesis at the site of brain injuries.

Whole-exome sequencing identifies a de novo TUBA1A mutation in a patient with sporadic malformations of cortical development: a case report

Background

Owing to the number of genetic mutations that contribute to malformations of cortical development, identification of causative mutations in candidate genes is challenging. To overcome these challenges, we performed whole-exome sequencing in this study.

Case presentation

A Japanese patient presented with microcephaly and severe developmental delay. Brain magnetic resonance imaging showed the presence of colpocephaly associated with lateral ventricle dilatation and the presence of a simplified gyral pattern. Hypoplasia of the corpus callosum and cerebellar vermis were also noted. Because Sanger sequencing is expensive, laborious, and time-consuming, whole-exome sequencing was performed and a de novo missense mutation in TUBA1A (E27Q) was identified.

Conclusion

The novel mutation identified in this study was located in the genetic region that encodes the N-terminal domain of TUBA1A, a region of TUBA1A with few reported mutations. Retrospective assessment of the clinical and radiological features of this patient―i.e., microcephaly, lissencephaly (pachygyria) with cerebellar hypoplasia, and corpus callosum hypoplasia―indicated that the TUBA1A mutation did not lead to any contradictions. Because rapid and comprehensive mutation analysis by whole-exome sequencing is time- and cost-effective, it might be useful for genetic counseling of patients with sporadic malformations of cortical development.

Abnormal pupillary light reflex with chromatic pupillometry in Gaucher disease

The hallmark of neuronopathic Gaucher disease (GD) is oculomotor abnormalities, but ophthalmological assessment is difficult in uncooperative patients. Chromatic pupillometry is a quantitative method to assess the pupillary light reflex (PLR) with minimal patient cooperation. Thus, we investigated whether chromatic pupillometry could be useful for neurological evaluations in GD. In our neuronopathic GD patients, red light-induced PLR was markedly impaired, whereas blue light-induced PLR was relatively spared. In addition, patients with non-neuronopathic GD showed no abnormalities. These novel findings show that chromatic pupillometry is a convenient method to detect neurological signs and monitor the course of disease in neuronopathic GD.

The useful preliminary diagnosis of Niemann-Pick disease type C by filipin test in blood smear

Niemann-Pick disease type C (NP-C) is an autosomal recessive lysosomal lipid storage disorder characterized with accumulation of cholesterol in endosomes and lysosomes. The diagnosis of NP-C is difficult due to its heterogeneous group of diseases. Biochemical diagnosis of NP-C is conducted by cholesterol staining with cultured skin fibroblasts and confirmed by the analysis of genetic mutations of NPC1 or NPC2 gene. Here, we report an easier biochemical diagnostic method with blood smear by filipin staining.

Effects of cyclodextrin in two patients with Niemann-Pick Type C disease

Niemann-Pick Type C disease (NPC) is an autosomal recessive lysosomal storage disorder characterized by progressive neurological deterioration. Currently, there are no effective treatments for NPC, although miglustat has shown some effectiveness in stabilizing neurological status in juvenile-onset NPC patients. Recent studies have demonstrated the efficacy of hydroxypropyl-β-cyclodextrin (HPB-CD) in NPC mice. Herein, we describe the effects of HPB-CD in two patients with NPC. The two patients received HPB-CD infusions twice (Patient 2) or thrice (Patient 1) weekly, starting with a dose of 80 mg/kg per dose that was increased gradually to 2g/kg per dose (Patient 2) or 2.5 g/kg per dose (Patient 1). Although HPB-CD did not improve the neurological deficits in either patient, it was partially effective in improving hepatosplenomegaly and central nervous system dysfunction, especially during the first 6 months of treatment. No adverse effects were observed over the course of treatment, although Patient 1 exhibited transient cloudiness of the lungs with fever after 2 years. For more effective treatment of NPC patients with HPB-CD, it is necessary to improve drug delivery into the central nervous system.

Clinical and serial MRI findings of a sialidosis type I patient with a novel missense mutation in the NEU1 gene

The case of a Japanese sialidosis type I patient with a novel NEU1 gene mutation is described. The patient developed an unsteady gait at age 14 and was referred to our hospital at age 16. On admission, subnormal intelligence, dysarthria, myoclonus, intentional tremors, limb and gait ataxia, hyperreflexia and macular cherry-red spots were observed. An enzymological analysis revealed a primary deficiency of neuraminidase. An NEU1 gene analysis identified two heterozygous missense mutations: p.P80L and p.D135N. The p.D135N mutation is a novel mutation that is considered to be associated with the mild clinical phenotype of sialidosis. Serial brain MRI showed diffuse brain atrophy progressing rapidly over the 41-month observation period.

Quantitative computed tomography for enzyme replacement therapy in Pompe disease

OBJECTIVE

Pompe disease is an autosomal recessive disorder caused by deficiency of the lysosomal enzyme, acid alpha-glucosidase (GAA). To the best of our knowledge, no studies have reported the results of systematic and sequential CT analyses before and during ERT. In this study we have treated three patients with late onset Pompe disease by ERT, and investigated the efficacy of treatment by computed tomography number.

METHODS

We measured the serial changes in the computed tomography (CT) number of multiple organs in three patients with late onset of Pompe disease during 24 months of enzyme replacement therapy (ERT).

RESULTS

Before treatment, the liver and muscle CT numbers were higher in these patients than in the controls. The liver CT number decreased after performing ERT. Furthermore, the urinary glucose tetrasaccharide levels, a biomarker of glycogen accumulation, were elevated before ERT and reduced thereafter.

CONCLUSIONS

The findings in these cases suggest that the elevation of the liver CT number represents glycogen accumulation in the liver and that the analysis of the liver CT number is therefore a useful tool for assessing the efficacy of ERT.

Associations between six classical HLA loci and rheumatoid arthritis: a comprehensive analysis

Although the HLA region contributes to one-third of the genetic factors affecting rheumatoid arthritis (RA), there are few reports on the association of the disease with any of the HLA loci other than the DRB1. In this study we examined the association between RA and the alleles of the six classical HLA loci including DRB1. Six HLA loci (HLA-A, -B, -C, -DRB1, -DQB1 and -DPB1) of 1659 Japanese subjects (622 cases; 488 anti-cyclic citrullinated peptides (CCP) antibody (Ab) positive (82.6%); 103 anti-CCP Ab negative (17.4%); 31 not known and 1037 controls) were genotyped. Disease types and positivity/negativity for CCP autoantibodies were used to stratify the cases. Statistical and genetic assessments were performed by Fisher's exact tests, odds ratio, trend tests and haplotype estimation. None of the HLA loci were significantly associated with CCP sero-negative cases after Bonferroni correction and we therefore limited further analyses to using only the anti CCP-positive RA cases and both anti-CCP positive and anti-CCP negative controls. Some alleles of the non-DRB1 HLA loci showed significant association with RA, which could be explained by linkage disequilibrium with DRB1 alleles. However, DPB1*02:01, DPB1*04:01 and DPB1*09:01 conferred RA risk/protection independently from DRB1. DPB1*02:01 was significantly associated with the highly erosive disease type. The odds ratio of the four HLA-loci haplotypes with DRB1*04:05 and DQB1*04:01, which were the high-risk HLA alleles in Japanese, varied from 1.01 to 5.58. C*07:04, and B*15:18 showed similar P-values and odds ratios to DRB1*04:01, which was located on the same haplotype. This haplotype analysis showed that the DRB1 gene as well as five other HLA loci is required for a more comprehensive understanding of the genetic association between HLA and RA than analyzing DRB1 alone.