Detection of transient abnormal myelopoiesis blasts in a liver biopsy specimen by double-immunostaining for full-length GATA1 and CD42b.

BACKGROUND: Transient abnormal myelopoiesis (TAM) is characterized by leukocytosis with increased circulating megakaryoblasts that harbor N-terminal truncating mutations in the GATA1 gene. Approximately 10% of affected patients experience early death. OBSERVATIONS: A 2-month-old boy with Down syndrome was diagnosed with TAM and followed without treatment. Although the blasts in the peripheral blood disappeared, liver failure progressed. A pathological examination revealed liver fibrosis, and double-immunostaining for full-length GATA1 and CD42b identified megakaryocytes with a GATA1 mutation. CONCLUSIONS: This simple and cost-effective method can be applied in routine practice to detect TAM blasts during assessment in a TAM crisis.

Monitoring with wearable devices will clarify the association between indoor temperature and blood pressure.

The association of blood pressure and temperature is well known in seasonal observation, and low temperature in the winter season is often considered a cause of high blood pressure. The current evidence for short-term studies of temperature and blood pressure is based on the daily observation, however continuous monitoring with wearable devices will allow us to evaluate the rapid effect of cold temperature exposure on blood pressure. In a Japanese, prospective intervention study from 2014 to 2019 (the Smart Wellness Housing survey), approximately 90% of Japanese lived in cold houses (indoor temperature less than 18 °C). Importantly, the indoor temperature was associated with the increase of morning systolic blood pressure. We recently addressed the sympathetic nervous activation of individuals in both their houses and a highly insulated and airtight model house in the winter season using portable electrocardiography equipment. A few subjects showed a morning surge in sympathetic activity, which was more intense at their cold houses, which suggests the importance of the indoor environment in the management of early morning hypertension. In near future, real-time monitoring with wearable devices will provide important information for a better life-environment, leading to risk reduction of morning surge and cardiovascular events.

Morning surge in sympathetic nervous activity in the indoor environment during the cold winter season.

We addressed to the sympathetic nervous activation of the same people in both their houses and a highly insulated and airtight model house (model house) during the cold winter season. Eight subjects (4 males and 4 females) stayed two nights at each house and were continuously monitored for sympathetic nerve system by calculating LF (low frequency)/HF (high frequency) in the analysis of heart rate variability using a wearable electrocardiography equipment. The room temperatures were kept constant at 20 °C or more in model house, but much lower in their houses. In all subjects, the sleeping duration is longer in model house compared with that in the participants' houses. Four subjects showed a morning surge in sympathetic activity that were more intense at their houses. This morning surge in sympathetic activity in a residential setting suggests the importance of the indoor environment in the management of early morning hypertension.

Immediate postnatal central hypothyroidism caused by maternal Graves' disease: Importance of early screening.

This report illustrates a case of central hypothyroidism in a newborn immediately after birth caused by maternal Graves' disease. Infants from mothers with Graves' disease require careful examination without waiting for neonatal screening results, even though the mother's thyroid function is normal at birth or the newborn does not have goiter.

Carbazole modification of ruthenium bipyridine-dicarboxylate oxygen evolution molecular catalysts.

We synthesized new oxygen-evolving molecular Ru(II) catalysts with one or two carbazole moieties on the axial pyridyl ligands, namely [Ru(bda)(cbz-py)(py)] and [Ru(bda)(cbz-py)2] [C1 and C2; bdaH2 = 2,2'-bipyridyl-6,6'-dicarboxylic acid, py = pyridine, and cbz-py = 9-(pyridin-4-yl)-9H-carbazole] to investigate the effect of cbz modification on the photophysical and catalytic properties of the well-known molecular catalyst [Ru(bda)(py)2] (C0). The initial oxygen-evolving catalytic activities of C1 and C2 were higher than that of C0 in both a chemical reaction driven by the strong oxidant (NH4)2[Ce(NO3)6] (CAN = ceric ammonium nitrate) and photochemical oxidation using a [Ru(bpy)3]2+ (bpy = 2,2'-bipyridine) photosensitizer with Na2S2O8 as the sacrificial oxidant. The higher activities were ascribed to the electron-withdrawing cbz groups, which promoted the radical coupling reaction to form a RuIV-O-O-RuIV species. A unique oxygen-evolution rate change behaviour was observed for both C1 and C2 in the presence of a large excess of CAN, suggesting the competitive oxidation of the cbz moiety during the chemical oxygen evolution reaction. This work suggests that the cbz modification of an oxygen evolution molecular catalyst is a promising approach for integrating the hole accumulator near the oxygen evolution catalytic centre.

In vitro functional analysis of four variants of human asparagine synthetase.

The loss-of-function variants of the human asparagine synthetase (ASNS) gene cause asparagine synthetase deficiency (ASNSD). Diagnosis of ASNSD requires genetic tests because a specific biochemical diagnostic for ASNSD is not available. There are a few reports describing the functional evaluation of ASNS variants. Therefore, in vitro methods are needed to evaluate the detected variants in patients. In this report, five types of human ASNS proteins (wild-type and our reported four variants: p.Leu145Ser, p.Leu247Trp, p.Val489Asp, and p.Trp541Cysfs*5) were expressed in silkworm using a baculoviral expression system. An enzymatic activity assay of ASNS was performed, and the concentration of asparagine by ninhydrin and High Performance Liquid Chromatography methods using the purified recombinant proteins was measured. We established ASNS deficient HEK293 cells using the CRISPR/Cas9 method and evaluated the growth of cells without asparagine after transduction of ASNS variants with a lentiviral expression system. The four ASNS variants displayed significantly low enzymatic activity. The ASNS deficient HEK293 cells transduced with wild-type ASNS grew without asparagine, whereas cells transduced with the variants did not grow or showed significantly slower growth than cells transduced with wild-type ASNS. Herein, we established a method for evaluating the enzymatic activity of the recombinant human ASNS variants. The results of the cell-based assay corroborated the results of the enzymatic activity. These methods should enable the evaluation of the pathogenicity of ASNS variants.

Japanese patients with mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase deficiency: In vitro functional analysis of five novel HMGCS2 mutations.

Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase (HMGCS2) deficiency is a metabolic disorder caused by mutations in the HMGCS2 gene. The present study describes the identification of four cases of HMGCS2 deficiency in Japan. Hepatomegaly and severe metabolic acidosis were observed in all cases. Fatty liver was identified in three cases, which suggested the unavailability of fatty acids. All patients presented with a high C2/C0 ratio, suggesting that the fatty acid oxidation pathway was normal during metabolic crisis. Genetic analyses revealed five rare, novel variants (p.G219E, p.M235T, p.V253A, p.S392L and p.R500C) in HMGCS2. To confirm their pathogenicity, a eukaryotic expression system and a bacterial expression system was adopted that was successfully used to obtain affinity-purified HMGCS2 protein with measurable activity. Purified M235T, S392L and R500C proteins did not retain any residual activity, whilst the V253A variant showed some residual enzymatic activity. Judging from the transient expression experiment in 293T cells, the G219E variant appeared to be unstable. In conclusion, the present study identified five novel variants of HMGCS2 that were indicated to be pathogenic in four patients affected by HMGCS2 deficiency.

Deficiency of 3-hydroxybutyrate dehydrogenase (BDH1) in mice causes low ketone body levels and fatty liver during fasting.

d-3-Hydroxy-n-butyrate dehydrogenase (BDH1; EC 1.1.1.30), encoded by BDH1, catalyzes the reversible reduction of acetoacetate (AcAc) to 3-hydroxybutyrate (3HB). BDH1 is the last enzyme of hepatic ketogenesis and the first enzyme of ketolysis. The hereditary deficiency of BDH1 has not yet been described in humans. To define the features of BDH1 deficiency in a mammalian model, we generated Bdh1-deficient mice (Bdh1 KO mice). Under normal housing conditions, with unrestricted access to food, Bdh1 KO mice showed normal growth, appearance, behavior, and fertility. In contrast, fasting produced marked differences from controls. Although Bdh1 KO mice survive fasting for at least 48 hours, blood 3HB levels remained very low in Bdh1 KO mice, and despite AcAc levels moderately higher than in controls, total ketone body levels in Bdh1 KO mice were significantly lower than in wild-type (WT) mice after 16, 24, and 48 hours fasting. Hepatic fat content at 24 hours of fasting was greater in Bdh1 KO than in WT mice. Systemic BDH1 deficiency was well tolerated under normal fed conditions but manifested during fasting with a marked increase in AcAc/3HB ratio and hepatic steatosis, indicating the importance of ketogenesis for lipid energy balance in the liver.

A rare PHKA2 variant (p.G991A) identified in a patient with ketotic hypoglycemia.

We describe the case of a 4-year-old boy who suffered from frequent ketotic hypoglycemia (KH) but did not have hepatomegaly or elevated liver enzyme levels. However, the patient was found to have a rare variant in the PHKA2 gene. To detect the underlying disease in this case, we performed a gene panel analysis covering 59 genes that are involved in fatty acid oxidation, ketone body metabolism and transport, and glycogen storage diseases. We found no reported disease-causing mutations. However, the p.G991A variant in PHKA2 was detected. The allele frequency of this variant is 4.57 × 10-5 in the population worldwide, but in Japan it is 5.15 × 10-3. We suspect that this variant may be a major cause of KH in Japanese patients. We performed an enzyme assay on blood cells from the patient. Although the activity of the current PhK variant was not low, it did exhibit thermal instability and a lower affinity to phosphorylase b than the wild type. The patient needed bedtime uncooked cornstarch supplementation from age 5 years until he was 9 years old. The patient's condition improved spontaneously without neurological complications. The clinical course and prognosis in this case are similar to those of glycogen storage disease type IXa, which is also caused by an abnormality of PHKA2.

A Japanese case of mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase deficiency who presented with severe metabolic acidosis and fatty liver without hypoglycemia.

Mitochondrial 3-hydroxy-3-methylglutaryl-CoA synthase deficiency (mHS deficiency) is a rare autosomal recessive inborn error of ketogenesis caused by a mutation in the HMGCS2 gene, which is characterized by non-(hypo)-ketotic hypoglycemia, lethargy, and hepatomegaly during acute infection and/or prolonged fasting. Clinical presentations are similar to fatty acid oxidation defects; however, diagnosis of mHS deficiency is difficult because of poor biochemical markers. We report the case of a 12-month-old Japanese boy with mHS deficiency who presented with a coma, and hepatomegaly, but no hypoglycemia after a febrile episode and poor oral intake. Metabolic acidosis and severe fatty liver were observed. Serum acylcarnitine analysis revealed a slightly decreased free carnitine (C0) level and an increased acetylcarnitine (C2) level. Urinary organic acid analysis revealed hypoketotic dicarboxylic aciduria, and increased excretions of glutarate, and, retrospectively, 4-hydroxy-6-methyl-2-pyrone. Although the patient did not present with hypoglycemia, the severe fatty liver and elevated free fatty acids to total ketone bodies ratio strongly suggested an inborn error of ketogenesis. In the analysis of the HMGCS2 gene, compound heterozygous mutations of c.130_131ins C (L44PfsX29) and c.1156_1157insC (L386PfsX73) were identified, which led to the diagnosis of mHS deficiency. He had recovered without any complication by the therapy, including intravenous glucose infusion. Unlike the previously reported cases of mHS deficiency, our case did not present with hypoglycemia and the fatty liver lasted over several months. mHS deficiency should be taken into consideration when a patient has severe metabolic acidosis and fatty liver with no or subtle ketosis, even without hypoglycemia.

Recent advances in understanding beta-ketothiolase (mitochondrial acetoacetyl-CoA thiolase, T2) deficiency.

Beta-ketothiolase (mitochondrial acetoacetyl-CoA thiolase, T2) deficiency (OMIM #203750, *607809) is an inborn error of metabolism that affects isoleucine catabolism and ketone body metabolism. This disorder is clinically characterized by intermittent ketoacidotic crises under ketogenic stresses. In addition to a previous 26-case series, four series of T2-deficient patients were recently reported from different regions. In these series, most T2-deficient patients developed their first ketoacidotic crises between the ages of 6 months and 3 years. Most patients experienced less than three metabolic crises. Newborn screening (NBS) for T2 deficiency is performed in some countries but some T2-deficient patients have been missed by NBS. Therefore, T2 deficiency should be considered in patients with severe metabolic acidosis, even in regions where NBS for T2 deficiency is performed. Neurological manifestations, especially extrapyramidal manifestations, can occur as sequelae to severe metabolic acidosis; however, this can also occur in patients without any apparent metabolic crisis or before the onset of metabolic crisis.

Differential Metabolic Responses to Adipose Atrophy Associated with Cancer Cachexia and Caloric Restriction in Rats and the Effect of Rikkunshito in Cancer Cachexia.

Despite the similar phenotypes, including weight loss, reduction of food intake, and lower adiposity, associated with caloric restriction (CR) and cancer cachexia (CC), CC is a progressive wasting syndrome, while mild CR improves whole body metabolism. In the present study, we compared adipose metabolic changes in a novel rat model of CC, mild CR (70% of the food intake of control rats, which is similar to the food consumption of CC rats), and severe CR (30% of the food intake of controls). We show that CC and severe CR are associated with much smaller adipocytes with significantly lower mitochondrial DNA content; but, that mild CR is not. CC and both mild and severe CR similarly upregulated proteins involved in lipolysis. CC also downregulated proteins involved in fatty acid biosynthesis, but mild CR upregulated these. These findings suggest that CC might impair de novo fatty acid biosynthesis and reduce mitochondrial biogenesis, similar to severe CR. We also found that rikkunshito, a traditional Japanese herbal medicine, does not ameliorate the enhanced lipolysis and mitochondrial impairment, but rather, rescues de novo fatty acid biosynthesis, suggesting that rikkunshito administration might have partially similar effects to mild CR.

Intronic antisense Alu elements have a negative splicing effect on the inclusion of adjacent downstream exons.

Alu elements occupy 10% of the human genome. However, although they contribute to genomic and transcriptomic diversity, their function is still not fully understood. We hypothesized that intronic Alu elements may contribute to alternative splicing. We therefore examined their effect on splicing using minigene constructs including exon 9-exon 11 inclusive of ACAT1 with truncated introns 9 and 10. These constructs contained a suboptimal splice acceptor site for intron 9. Insertion of AluY-partial AluSz6-AluSx, originally located in ACAT1 intron 5, in an antisense direction within intron 9 had a negative effect on exon 10 inclusion. This effect was additive with that of an exonic splicing enhancer mutation in exon 10, and was canceled by the substitution of G for C at the first nucleotide of exon 10 which optimized the splice acceptor site of intron 9. A sense AluY-partial AluSz6-AluSx insertion had no effect on exon 10 inclusion, and one antisense AluSx insertion had a similar effect to antisense AluY-partial AluSz6-AluSx insertion. The shorter the distance between the antisense Alu element and exon 10, the greater the negative effect on exon 10 inclusion. This distance effect was more evident for suboptimal than optimal splice sites. Based on our data, we propose that intronic antisense Alu elements contribute to alternative splicing and transcriptomic diversity in some genes, especially when splice acceptor sites are suboptimal.

Acute bacterial endophthalmitis after scleral buckling surgery with chandelier endoillumination.

PURPOSE: The non-contact wide-angle viewing system (WAVS) with chandelier endoillumination is being used more commonly during scleral buckling surgery for rhegmatogenous retinal detachments although its safety has not been established. We report our findings in a case of bacterial endophthalmitis that developed after scleral buckling surgery with WAVS and chandelier endoillumination. OBSERVATIONS: A 42-year-old man underwent scleral buckling surgery for a rhegmatogenous retinal detachment in his right eye using a WAVS with chandelier endoillumination. Three days after the surgery, the patient noticed a marked decrease in his vision with ocular pain. Slit-lamp examination showed dense infiltration in the anterior chamber and vitreous body. Pars plana vitrectomy with antibiotic irrigation was done immediately, and Staphylococcus epidermidis was detected in the vitreous fluid. After vancomycin 6/day for 4 weeks, the inflammation gradually subsided, and the visual acuity recovered to 20/20 in 3 months. CONCLUSIONS AND IMPORTANCE: Acute bacterial endophthalmitis can develop after scleral buckling surgery performed with WAVS and chandelier endoillumination.

Reproducibility and differences in area of foveal avascular zone measured by three different optical coherence tomographic angiography instruments.

This study was performed to compare the area of the foveal avascular zone (FAZ-area) obtained by three optical coherence tomography angiography (OCTA) instruments. This was a cross-sectional, non-interventional study of twenty-seven healthy right eyes. The superficial and deep FAZ-area was measured manually with three OCTA instruments: Triton (Topcon), RS3000 (Nidek), and CIRRUS (Zeiss). The intra-rater, inter-rater, and inter-instrument correlation coefficients (CC) were assessed. The intra-rater and inter-rater CC were significantly high for the superficial and deep FAZ-areas (P < 0.001). The inter-instrument CC (95% confidence interval) for the superficial FAZ-area was 0.920 (0.803-0.965) for Triton vs RS3000, 0.899 (0.575-0.965) for RS3000 vs CIRRUS, and was 0.963 (0.913-0.983) for CIRRUS vs Triton (P < 0.001). For the deep FAZ-area, the inter-instrument CC was 0.813 (0.633-0.910) for Triton vs RS3000, 0.694 (0.369-0.857) for RS3000 vs CIRRUS, and 0.679 (0.153-0.872) for CIRRUS vs Triton (P < 0.001). The superficial FAZ-area (mm2) was 0.264 ± 0.071 with Triton, 0.278 ± 0.072 with RS3000 and 0.257 ± 0.066 with CIRRUS. For deep FAZ-area, it was 0.617 ± 0.175 with Triton, 0.646 ± 0.178 with RS3000 and 0.719 ± 0.175 with CIRRUS. The FAZ-area from these instruments was clinically interchangeable. However, the absolute values of FAZ-area are significantly different among them. These differences must be considered in comparing the FAZ-areas from different OCTA instruments.

Heterozygous carriers of succinyl-CoA:3-oxoacid CoA transferase deficiency can develop severe ketoacidosis.

Succinyl-CoA:3-oxoacid CoA transferase (SCOT, gene symbol OXCT1) deficiency is an autosomal recessive disorder in ketone body utilization that results in severe recurrent ketoacidotic episodes in infancy, including neonatal periods. More than 30 patients with this disorder have been reported and to our knowledge, their heterozygous parents and siblings have had no apparent ketoacidotic episodes. Over 5 years (2008-2012), we investigated several patients that presented with severe ketoacidosis and identified a heterozygous OXCT1 mutation in four of these cases (Case1 p.R281C, Case2 p.T435N, Case3 p.W213*, Case4 c.493delG). To confirm their heterozygous state, we performed a multiplex ligation-dependent probe amplification analysis on the OXCT1 gene which excluded the presence of large deletions or insertions in another allele. A sequencing analysis of subcloned full-length SCOT cDNA showed that wild-type cDNA clones were present at reasonable rates to mutant cDNA clones. Over the following 2 years (2013-2014), we analyzed OXCT1 mutations in six more patients presenting with severe ketoacidosis (blood pH ≦7.25 and total ketone body ≧10 mmol/L) with non-specific urinary organic acid profiles. Of these, a heterozygous OXCT1 mutation was found in two cases (Case5 p.G391D, Case6 p.R281C). Moreover, transient expression analysis revealed R281C and T435N mutants to be temperature-sensitive. This characteristic may be important because most patients developed ketoacidosis during infections. Our data indicate that heterozygous carriers of OXCT1 mutations can develop severe ketoacidotic episodes in conjunction with ketogenic stresses.

Single-nucleotide substitution T to A in the polypyrimidine stretch at the splice acceptor site of intron 9 causes exon 10 skipping in the ACAT1 gene.

BACKGROUND: ß-ketothiolase (T2, gene symbol ACAT1) deficiency is an autosomal recessive disorder, affecting isoleucine and ketone body metabolism. We encountered a patient (GK03) with T2 deficiency whose T2 mRNA level was <10% of the control, but in whom a previous routine cDNA analysis had failed to find any mutations. Genomic PCR-direct sequencing showed homozygosity for c.941-9T>A in the polypyrimidine stretch at the splice acceptor site of intron 9 of ACAT1. Initially, we regarded this variant as not being disease-causing by a method of predicting the effect of splicing using in silico tools. However, based on other findings of exon 10 splicing, we eventually hypothesized that this mutation causes exon 10 skipping. METHODS: cDNA analysis was performed using GK03's fibroblasts treated with/without cycloheximide (CHX), since exon 10 skipping caused a frameshift and nonsense-mediated mRNA decay (NMD). Minigene splicing experiment was done to confirm aberrant splicing. RESULTS: cDNA analysis using fibroblasts cultured with cycloheximide indeed showed the occurrence of exon 10 skipping. A minigene splicing experiment clearly showed that the c.941-9T>A mutant resulted in transcripts with exon 10 skipping. There are few reports describing that single-nucleotide substitutions in polypyrimidine stretches of splice acceptor sites cause aberrant splicing. CONCLUSION: We showed that c.941-9T>A induces aberrant splicing in the ACAT1 gene. Our ability to predict the effects of mutations on splicing using in silico tools is still limited. cDNA analysis and minigene splicing experiments remain useful alternatives to reveal splice defects.

A novel mutation (c.121­13T>A) in the polypyrimidine tract of the splice acceptor site of intron 2 causes exon 3 skipping in mitochondrial acetoacetyl-CoA thiolase gene.

Mitochondrial acetoacetyl-CoA thiolase (T2) (gene symbol: ACAT1) deficiency is an autosomal recessive disorder affecting isoleucine catabolism and ketone body utilization. In this study, mutational analysis of an Indian T2-deficient patient revealed a homozygous mutation (c.121­13T>A) located at the polypyrimidine tract of the splice acceptor site of intron 2, and exon 3 skipping was identified by cDNA analysis using cycloheximide. We made three mutant constructs (c.121­13T>A, T>C, and T>G substitutions) followed by making a wild-type minigene construct that included an ACAT1 segment from exon 2 to 4 for a splicing experiment. The minigene splicing experiment demonstrated that exon 3 skipping was induced not only by c.121­13T>A mutation, but also by the other two substitutions. It was difficult to predict the effect of these mutations on splicing using in silico tools, as predictions of different tools were inconsistent with each other. The minigene splicing experiment remains the most reliable method to unravel splicing abnormalities.