Clinical spectrum, over 12-year follow-up and experience of SGLT2 inhibitors treatment on patients with glycogen storage disease type Ib: a single-center retrospective study.

BACKGROUND: Glycogen storage disease type Ib (GSD Ib) is a rare disorder characterized by impaired glucose homeostasis caused by mutations in the SLC37A4 gene. It is a severe inherited metabolic disease associated with hypoglycemia, hyperlipidemia, lactic acidosis, hepatomegaly, and neutropenia. Traditional treatment consists of feeding raw cornstarch which can help to adjust energy metabolism but has no positive effect on neutropenia, which is fatal for these patients. Recently, the pathophysiologic mechanism of the neutrophil dysfunction and neutropenia in GSD Ib has been found, and the treatment with the SGLT2 inhibitor empaglifozin is now well established. In 2020, SGLT2 inhibitor empagliflozin started to be used as a promising efficient remover of 1,5AG6P in neutrophil of GSD Ib patients worldwide. However, it is necessary to consider long-term utility and safety of a novel treatment. RESULTS: In this study, we retrospectively examined the clinical manifestations, biochemical examination results, genotypes, long-term outcomes and follow-up of thirty-five GSD Ib children who visited our department since 2009. Fourteen patients among them underwent empagliflozin treatment since 2020. This study is the largest cohort of pediatric GSD Ib patients in China as well as the largest cohort of pediatric GSD Ib patients treated with empagliflozin in a single center to date. The study also discussed the experience of long-term management on pediatric GSD Ib patients. CONCLUSION: Empagliflozin treatment for pediatric GSD Ib patients is efficient and safe. Increase of urine glucose is a signal for pharmaceutical effect, however attention to urinary infection and hypoglycemia is suggested.

Breaking prolonged sitting increases 24-h physical activity and self-perceived energy levels but does not acutely affect cognition in healthy adults.

INTRODUCTION: It is unknown whether predetermined (un)interrupted sitting within a laboratory setting will induce compensatory changes in human behaviours (energy intake and physical activity) once people return to a free-living environment. The effects of breaking up prolonged sitting on cognition are also unclear. METHODS: Twenty-four (male = 13) healthy participants [age 31 ± 8 y, BMI 22.7 ± 2.3 kg/m2 (mean ± SD)] completed 320 min mixed-feeding trials under prolonged sitting (SIT) or with 2 min walking at 6.4 km/h every 20 min (ACTIVE), in a randomised crossover design. Human behaviours were recorded post-trial under free-living conditions until midnight. Cognitive performance was evaluated before and immediately after SIT and ACTIVE trials. Self-perceived sensations (appetite, energy and mood) and finger prick blood glucose levels were collected at regular intervals throughout the trials. RESULTS: There were no differences between trials in eating behaviour and spontaneous physical activity (both, p > 0.05) in free-living conditions, resulting in greater overall total step counts [11,680 (10740,12620) versus 6049 (4845,7253) steps] and physical activity energy expenditure (PAEE) over 24-h period in ACTIVE compared to SIT (all, p < 0.05). Greater self-perceived levels of energy and lower blood glucose iAUC were found in ACTIVE trial compared to SIT trial (both, p < 0.05). No differences were found in cognitive performance between trials (all, p > 0.05). CONCLUSION: Breaking up sitting does not elicit subsequent behavioural compensation, resulting in greater 24-h step counts and PAEE in healthy adults. Breaking up sitting reduces postprandial glucose concentrations and elicits greater self-perceived energy levels, but these positive effects do not acutely translate into improved cognitive function.

Diagnosis of an intermediate case of maple syrup urine disease: A case report.

BACKGROUND: Maple syrup urine disease (MSUD) is an autosomal recessive genetic disorder caused by defects in the catabolism of the branched-chain amino acids (BCAAs). However, the clinical and metabolic screening is limited in identifying all MSUD patients, especially those patients with mild phenotypes or are asymptomatic. This study aims to share the diagnostic experience of an intermediate MSUD case who was missed by metabolic profiling but identified by genetic analysis. CASE SUMMARY: This study reports the diagnostic process of a boy with intermediate MSUD. The proband presented with psychomotor retardation and cerebral lesions on magnetic resonance imaging scans at 8 mo of age. Preliminary clinical and metabolic profiling did not support a specific disease. However, whole exome sequencing and subsequent Sanger sequencing at 1 year and 7 mo of age identified bi-allelic pathogenic variants of the BCKDHB gene, confirming the proband as having MSUD with non-classic mild phenotypes. His clinical and laboratory data were retrospectively analyzed. According to his disease course, he was classified into an intermediate form of MSUD. His management was then changed to BCAAs restriction and metabolic monitoring conforming to MSUD. In addition, genetic counseling and prenatal diagnosis were provided to his parents. CONCLUSION: Our work provides diagnostic experience of an intermediate MSUD case, suggesting that a genetic analysis is important for ambiguous cases, and alerts clinicians to avoid missing patients with non-classic mild phenotypes of MSUD.

Mitochondrial FAD shortage in SLC25A32 deficiency affects folate-mediated one-carbon metabolism.

The SLC25A32 dysfunction is associated with neural tube defects (NTDs) and exercise intolerance, but very little is known about disease-specific mechanisms due to a paucity of animal models. Here, we generated homozygous (Slc25a32Y174C/Y174C and Slc25a32K235R/K235R) and compound heterozygous (Slc25a32Y174C/K235R) knock-in mice by mimicking the missense mutations identified from our patient. A homozygous knock-out (Slc25a32-/-) mouse was also generated. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice presented with mild motor impairment and recapitulated the biochemical disturbances of the patient. While Slc25a32-/- mice die in utero with NTDs. None of the Slc25a32 mutations hindered the mitochondrial uptake of folate. Instead, the mitochondrial uptake of flavin adenine dinucleotide (FAD) was specifically blocked by Slc25a32Y174C/K235R, Slc25a32K235R/K235R, and Slc25a32-/- mutations. A positive correlation between SLC25A32 dysfunction and flavoenzyme deficiency was observed. Besides the flavoenzymes involved in fatty acid ß-oxidation and amino acid metabolism being impaired, Slc25a32-/- embryos also had a subunit of glycine cleavage system-dihydrolipoamide dehydrogenase damaged, resulting in glycine accumulation and glycine derived-formate reduction, which further disturbed folate-mediated one-carbon metabolism, leading to 5-methyltetrahydrofolate shortage and other folate intermediates accumulation. Maternal formate supplementation increased the 5-methyltetrahydrofolate levels and ameliorated the NTDs in Slc25a32-/- embryos. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice had no glycine accumulation, but had another formate donor-dimethylglycine accumulated and formate deficiency. Meanwhile, they suffered from the absence of all folate intermediates in mitochondria. Formate supplementation increased the folate amounts, but this effect was not restricted to the Slc25a32 mutant mice only. In summary, we established novel animal models, which enabled us to understand the function of SLC25A32 better and to elucidate the role of SLC25A32 dysfunction in human disease development and progression.

Laminin-511 and recombinant vitronectin supplementation enables human pluripotent stem cell culture and differentiation on conventional tissue culture polystyrene surfaces in xeno-free conditions.

Human pluripotent stem cells (hPSCs) are typically cultivated on extracellular matrix (ECM) protein-coated dishes in xeno-free culture conditions. We supplemented mixed ECM proteins (laminin-511 and recombinant vitronectin, rVT) in culture medium for hPSC culture on conventional polystyrene dishes. Three hPSC cell lines were successfully cultivated on uncoated polystyrene dishes in medium supplemented with optimal conditions of laminin-511 and rVT. Excellent colony shape and colony size as well as high expansion fold of hPSCs were found under these conditions, whereas the colony size was small and poor expansion fold was found solely on L-511-coated dishes. A small portion of L-511 in the culture medium supported hPSC adhesion and prevented the adhesion from being too strong on the uncoated dishes, and rVT in the culture medium further supported adhesion of hPSCs on the dishes by maintaining their pluripotency. Having the optimal composition of L-511 and rVT in the culture medium was important for generating good hPSC colony shapes and sizes as well as a high expansion fold. After long-term culture of hPSCs on uncoated dishes supplemented with the mixed proteins, the hPSCs successfully showed pluripotent markers and could differentiate into a specific lineage of cells, cardiomyocytes, with high efficiency.

Lightweight deep neural networks for cholelithiasis and cholecystitis detection by point-of-care ultrasound.

BACKGROUND AND OBJECTIVE: Emergency physicians (EPs) frequently deal with abdominal pain, including that is caused by either gallstones or acute cholecystitis. Easy access and low cost justify point-of-care ultrasound (POCUS) use as a first-line test to detect these diseases; yet, the detection performance of POCUS by EPs is unreliable, causing misdiagnoses with serious impacts. This study aimed to develop a machine learning system to detect and localize gallstones and to detect acute cholecystitis by ultrasound (US) still images taken by physicians or technicians for preliminary diagnoses. METHODS: Abdominal US images (> 89,000) were collected from 2386 patients in a hospital database. We constructed training sets for gallstones with or without cholecystitis (N = 10,971) and cholecystitis with or without gallstones (N = 7348) as positives. Validation sets were also constructed for gallstones (N = 2664) and cholecystitis (N = 1919). We applied a single-shot multibox detector (SSD) and a feature pyramid network (FPN) to classify and localize objects using image features extracted by ResNet-50 for gallstones, and MobileNet V2 to classify cholecystitis. The deep learning models were pretrained using the COCO-2017 and ILSVRC-2012 datasets. RESULTS: Using the validation sets, the SSD-FPN-ResNet-50 and MobileNet V2 achieved areas under the receiver operating characteristics curve of 0.92 and 0.94, respectively. The inference speeds were 21 (47.6 frames per second, fps) and 7 ms (142.9 fps). CONCLUSIONS: A machine learning system was developed to detect and localize gallstones, and to detect cholecystitis, with acceptable discrimination and speed. This is the first study to develop this system for either gallstone or cholecystitis detection with absence or presence of each one. After clinical trials, this system may be used to assist EPs, including those in remote areas, for detecting these diseases.

Clinical and biochemical characteristics of patients with ornithine transcarbamylase deficiency.

BACKGROUND: Ornithine transcarbamylase deficiency (OTCD) is pleomorphic congenital hyperammonemia, in which the prognosis of the patient is determined both by genotype and environmental factors. This study investigated the clinical and biochemical characteristics of OTCD patients with different prognosis. METHOD: Of 35 OTCD patients, six males deceased at the first disease-onset, 17 males survived and had controllable ammonia levels after treatment, and 12 females survived through the first disease-onset but had intractable hyperammonemia and high mortality. Fasting blood samples from patients collected at three disease stages were used for the analysis of amino acid (AA) profile, acylcarnitine profile, and micronutrients. Differences in profiles between patients and healthy controls and within patient groups were studied. RESULTS: All OTCD patients had accumulation of glutamine, homocitrulline, lysine, glutamate, cystathionine, and pipecolic acid, as well as deficiency of citrulline, tryptophan, threonine, and carnitine. For male non-survivors, most other AAs and long-chain acylcarnitines were elevated at disease onset, of which the levels of creatine, N-acetylaspartic acid, and homoarginine were remarkably high. Male survivors and female patients had most other AAs at low to normal levels. Compared with male survivors, female patients had much lower protein-intolerance, as indicated by significantly lower levels of protein consumption indicators, including essential AAs, 1-methylhistidine, acylcarnitines et al., but high levels of ammonia. Female patients still had significantly higher levels of citrulline, homocitrulline, and citrulline/arginine compared to male survivors. CONCLUSION: Unique profiles were observed in each group of OTCD patients, indicating specific physiological changes that happened to them.

Novel mutations in a Chinese family with two patients with succinic semialdehyde dehydrogenase deficiency.

Background: A considerable proportion of pediatric disease burden is mainly caused by inborn errors of metabolism. Succinic semi-aldehyde dehydrogenase (SSADH) deficiency is an unusual disorder of the gamma-aminobutyric acid metabolism. Till date, very few cases have been reported in China.Case presentation: Trio-WES was used to characterize the ALDH5A1 gene in two children of a Chinese family, who presented with seizures, psychomotor delay, development regression, borderline cognition, hypotonia, and harbored the compound heterozygotes NM_001080.3: c.1321G > A (p. Gly441Arg) and c.727_735del (p. Leu243_Ser245del). The former has been reported earlier (rs1041467895), whereas the latter is novel. Amino acid coding at highly conserved amino acid residues was observed to be altered by both mutations. This structural impairment influenced the enzyme structure as indicated by the in silico protein modeling. Cerebral magnetic resonance imaging of the proband and her brother showed excessive gap in the cerebrum and abnormal signals in the bilateral frontal lobe, bilateral basal ganglia, and cerebral foot. Elevated levels of Gamma-hydroxybutyric aciduria were found in their patients on urine organic acid analysis.Conclusion: Our findings contribute to the current knowledge of missense and deletion mutations associated with SSADH deficiency.

Budget impact analysis of osteoporosis medications for primary prevention of fractures in Taiwan.

INTRODUCTION: Taiwan's national health insurance currently only covers the use of osteoporosis drugs for the secondary prevention of fractures and does not provide coverage for primary prevention. The purpose of this study is to develop a model for analyzing the budgetary impact of the use of osteoporosis medications of primary prevention. METHODS: The budget impact model in this study is the "actual medication cost" minus the "medical expenses for all types of fractures that can be avoided by taking osteoporosis medications." We developed six possible insurance payment plans for primary prevention based on the age of the patients and T-scores and performed eleven steps to estimate the budget impact of each payment plan. RESULTS: The results of this study indicated that there may be 71,220 (T-score ≤ - 3.0, 75 + y/o) to 157,515 (T-score ≤ - 2.5, 65 + y/o) people using the drugs, and the budget impact may be US$26.28-58.98 million in 2019. However, the payment plans may avoid 492-766 fracture events and save medical expenditures for fracture treatment by US$1.30-2.02 million. The average costs for primary prevention within a year will be US$53,386-77,006. CONCLUSION: The budget impact of using osteoporosis medications to primary prevention of fractures is significant, but it can be compensated due to savings in fracture treatment costs.

Simultaneous quantification of 48 plasma amino acids by liquid chromatography-tandem mass spectrometry to investigate urea cycle disorders.

Urea cycle disorders (UCD) are inborn errors of ammonia detoxification in which early diagnosis and treatment are critical to prevent metabolic emergencies. Unfortunately, the diagnosis was often and pronounced delayed. To improve diagnosis, we developed herein a liquid chromatography-tandem mass spectrometry method to investigate the disturbance of amino acid profile caused by UCD. The method enabled absolute quantification of 48 amino acids (AAs) within 20 min. Only 2.5 µL plasma was required for the analysis. The lower limits of quantification for most AAs were 0.01 µmol/L. Method accuracies ranged from 89.9% to 113.4%. The within- and between-run coefficients of variation were 0.8-7.7% and 2.6-14.5%, respectively. With this method, age-specific reference values were established for 42 AAs by analyzing 150 samples from normal controls, and patients with different subtypes of UCD were successfully distinguished. The data of patients revealed that UCD not only disturbed the metabolism of urea cycle AAs and induced accumulation of ammonia detoxification AAs, but also interfered the metabolism of some nervous system related AAs, such as pipecolic acid and N-acetylaspartic acid. This data may provide new insight into pathogenesis for UCD.