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Patients with urea cycle disorders intermittently develop episodes of decompensation with hyperammonemia. Although such an episode is often associated with starvation and catabolism, its molecular basis is not fully understood. First, we attempted to elucidate the mechanism of such starvation-associated hyperammonemia. Using a mouse embryonic fibroblast (MEF) culture system, we found that glucose starvation increases ammonia production, and that this increase is associated with enhanced glutaminolysis. These results led us to focus on α-ketoglutarate (AKG), a glutamate dehydrogenase inhibitor, and a major anaplerotic metabolite. Hence, we sought to determine the effect of dimethyl α-ketoglutarate (DKG), a cell-permeable AKG analog, on MEFs and found that DKG mitigates ammonia production primarily by reducing flux through glutamate dehydrogenase. We also verified that DKG reduces ammonia in an NH

Importance Sapropterin hydrochloride, a natural coenzyme (6R-tetrahydrobiopterin) of phenylalanine hydroxylase, was first approved as a treatment for tetrahydrobiopterin deficiency in 1992 in Japan, and was then approved as a treatment for a tetrahydrobiopterin-responsive hyperphenylalaninemia in 2007 and 2008, in the USA and Japan, respectively. Guidelines are required on the proper use of sapropterin hydrochloride for tetrahydrobiopterin-responsive hyperphenylalaninemia. Observations It is recommended that tetrahydrobiopterin-responsive hyperphenylalaninemia should be diagnosed in all cases of hyperphenylalaninemia, including phenylketonuria, by tetrahydrobiopterin administration tests rather than by phenotype or blood phenylalanine levels. Conclusions and relevance If tetrahydrobiopterin-responsive hyperphenylalaninemia is diagnosed, all ages can be treated with sapropterin hydrochloride. Although there are reports that sapropterin hydrochloride is effective and safe for the prevention of maternal phenylketonuria, further investigation is required.

This is the first report for a Japanese case of arthrochalasia type of Ehlers-Danlos syndrome (EDS). A 46-year-old woman consulted us for joint hypermobility and skin hyperextensibility that had been present soon after birth. There was no family history of a similar disease. She was diagnosed as having bilateral congenital hip dislocation and bilateral habitual shoulder dislocation at her childhood. Her skin was velvety, doughy and hyperextensible. She showed hypermobility of the joints of the hands and feet and generalized joint laxity, with no evidence of scoliosis. Electrophoretic analysis of collagenous proteins revealed the presence of an additional band in the position of pNα2(I) in the sample from culture medium of the patient fibroblasts. Analysis of the α2 chains of type I collagen gene, COL1A2, showed a heterozygous G to T transition at the +1 position of the exon 6 donor splice site (c.279+1G>T). This mutation resulted in skipping of exon 6, which leads to deficient processing of the amino-terminal end of proα2(I) chains of type I collagen. Based on these findings, we made a diagnosis of the arthrochalasia type of EDS, which corresponds to EDS type VIIB in the former classification.

We report the case of a family with late-onset ornithine transcarbamylase deficiency (OTCD). Several family members had died from OTCD, and the c.221G>A, p.Lys221Lys mutation was detected at the 3' end of exon 6 of OTC in the X-chromosome of some members. We provided genetic counseling on pregnancy, delivery, and neonate management to a 4th-generation female carrier and decided on metabolic management of her child from birth. Two male patients were diagnosed with late-onset OTCD on the basis of blood amino acid and genetic analysis, and they received arginine supplementation from the asymptomatic, early neonatal period. These children grew and developed normally, without decompensation. Patients with late-onset OTCD can and should be diagnosed and treated in the early neonatal period, especially those from families already diagnosed with late-onset OTCD, and family members must be provided with genetic counseling.

Kabuki syndrome is a congenital anomaly syndrome characterized by developmental delay, intellectual disability, specific facial features including long palpebral fissures and ectropion of the lateral third of the lower eyelids, prominent digit pads, and skeletal and visceral abnormalities. Mutations in MLL2 and KDM6A cause Kabuki syndrome. We screened 81 individuals with Kabuki syndrome for mutations in these genes by conventional methods (n = 58) and/or targeted resequencing (n = 45) or whole exome sequencing (n = 5). We identified a mutation in MLL2 or KDM6A in 50 (61.7%) and 5 (6.2%) cases, respectively. Thirty-five MLL2 mutations and two KDM6A mutations were novel. Non-protein truncating-type MLL2 mutations were mainly located around functional domains, while truncating-type mutations were scattered through the entire coding region. The facial features of patients in the MLL2 truncating-type mutation group were typical based on those of the 10 originally reported patients with Kabuki syndrome; those of the other groups were less typical. High arched eyebrows, short fifth finger, and hypotonia in infancy were more frequent in the MLL2 mutation group than in the KDM6A mutation group. Short stature and postnatal growth retardation were observed in all individuals with KDM6A mutations, but in only half of the group with MLL2 mutations.

Citrin-deficient children and adolescents between adult-onset type II citrullinemia and neonatal intrahepatic cholestasis by citrin deficiency do not have clear clinical features except for unusual diet of high-fat, high-protein, and low-carbohydrate food. The aims of the present study are to characterize fatigue and quality of life (QOL) in citrin-deficient patients during adaptation and compensation stage, and to define the relationship between fatigue and QOL. The study subjects were 55 citrin-deficient patients aged 1-22years (29 males) and 54 guardians. Fatigue was evaluated by self-reports and proxy-reports of the PedsQL Multidimensional Fatigue Scale. QOL was evaluated by the PedsQL Generic Core Scales. Both scale scores were significantly lower in child self-reports (p0.01 and p0.05, respectively) and parent proxy-reports (p0.01 and p0.01, respectively) than those of healthy children. Citrin-deficient patients with scores of 50 percentile or less of healthy children constituted 67.5% of the sample for the Fatigue Scale and 68.4% for the Generic Core Scales. The PedsQL Fatigue Scale correlated with the Generic Core Scales for both the patients (r=0.56) and parents reports (r=0.71). Assessments by the patients and their parents showed moderate agreement. Parents assessed the condition of children more favorably than their children. The study identified severe fatigue and impaired QOL in citrin-deficient patients during the silent period, and that such children perceive worse fatigue and poorer QOL than those estimated by their parents. The results stress the need for active involvement of parents and medical staff in the management of citrin-deficient patients during the silent period.

Recently, plasma globotriaosylsphingosine (lyso-Gb3) has attracted attention as a biomarker of Fabry disease. However, we found a subset of Fabry disease patients who did not show any increase in the plasma lyso-Gb3 concentration, although other patients exhibited apparent enhancement of it. This subset predominantly exhibited the clinical phenotype of later-onset Fabry disease, and gene analysis revealed that the patients harbored the M296I mutation common to Japanese Fabry patients. This amino acid substitution is predicted to cause a small conformational change on the surface of the α-galactosidase A molecule, resulting in residual enzyme activity. Plasma lyso-Gb3 is a good biomarker of Fabry disease but care should be taken when it is used for a definitive diagnosis.

Urea cycle disorders (UCDs) are one of the most frequently inherited metabolic diseases in Japan, with an estimated prevalence of 1 per 50,000 live births. Here, we investigated the clinical manifestations, treatment, and prognosis of 177 patients with UCDs who were evaluated and treated from January 1999 to March 2009. These included 77 cases of neonatal-onset UCDs and 91 cases of late-onset UCDs. The most common UCD was ornithine transcarbamylase deficiency (OTCD), which accounted for 116 out of 177 patients. This result is similar to a previous study performed between 1978 and 1995 in Japan: OTCD accounted for about two-thirds of the total number of UCD cases. We studied the relationship between prognosis and the peak blood ammonia level at the onset in 151 UCD patients. Compared with a previous survey conducted in Japan, we found that a greater number of patients survived without any mental retardation despite their peak blood ammonia levels being greater than 360 μmol/l. The 5-year survival rate of patients with OTCD improved to 86% for those with the neonatal-onset type and to 92% for those with the late-onset type. We hypothesize that the increased survival rate is due to early diagnosis and better treatments that are now available in Japan. It is very important to diagnose and treat UCDs, especially OTCD, when the blood ammonia levels in patients are low. The outcome in patients with low blood ammonia levels was better than that in patients with high blood ammonia levels.

We assessed whether laronidase (recombinant human α-L-iduronidase) replacement therapy could improve left ventricular (LV) myocardial function in a 49-year-old woman with mucopolysaccharidosis I (MPS I) and valvular heart disease. After 6 months of laronidase treatment, the concentration of urinary uron acid decreased by 78.8%. Hepatosplenomegaly improved and LV weight decreased by 19.6%. LV ejection fraction assessed by two-dimensional echocardiogram did not change after laronidase treatment. However, in two-dimensional ultrasound speckle tracking imaging method, LV myocardial longitudinal strain (shortening ratio) increased from -13.2 to -17.4%. LV myocardial radial strain (thickening ratio) increased from 26.6 to 83.4%. LV myocardial torsion increased from +6 to +18°. These indexes of myocardial function were normalized after laronidase treatment. Thus, our findings were a first report that laronidase treatment had a beneficial effect on LV myocardial function in an adult patient with MPS I.

The mechanism underlying the development of osteopenia or osteoporosis in longstanding phenylketonuria (PKU) remains to be clarified. We investigated the details of bone metabolism in 21 female and 13 male classical PKU patients aged 20–35 years. Vitamin D (VD), parathyroid hormone (PTH), bone turnover markers, and daily nutrient intake were examined. The patients had lower daily energy and protein intake than did the age-matched controls (22 women, 14 men), but their respective fat, VD, and calcium intake did not differ. Serum 1,25-dihydroxy VD and 25-hydroxy VD levels in female and male patient groups were significantly higher and lower than those in respective control groups (females, P

P>BackgroundRecent studies suggest that refractory hypotension from causes other than septicaemia or cardiac failure is common in extremely preterm infants even out of the transitional period. Marked response to low-dose cortisol suggests underlying adrenal insufficiency, although the exact mechanism remains unknown.MethodsTo investigate potential triggers for and related short-term outcomes of early-onset ( = Day 7) refractory hypotension, clinical data for 70 infants < 30 weeks gestation were assessed.ResultsThe incidence of early-onset refractory hypotension (n = 7) was correlated with younger gestational ages < 26 weeks (P < 0 center dot 05), whereas the incidence of late-onset refractory hypotension (n = 14) was correlated with younger gestational ages and levothyroxine supplementation (P < 0 center dot 05 and 0 center dot 01, respectively). The incidence of both early- and late-onset refractory hypotension was correlated with risks of short-term adverse outcomes such as prolonged mechanical ventilation and hospital stay.ConclusionsLevothyroxine supplementation was identified as an independent variable correlated with an increased incidence of refractory hypotension out of the transitional period; as seen in hypothyroidism with Addison's disease, the immature hypothalamic-pituitary-adrenal axis may not respond properly to the increased demand for cortisol, which may precipitate premature infants into refractory hypotension. Following the administration of levothyroxine, preterm infants may have to be carefully monitored for early signs of refractory hypotension.

Neuropathology and neuroimaging of long-term survival cases of arginase deficiency are rarely reported. The magnetic resonance imaging (MRI) of our case showed severe multicystic white matter lesions with cortical atrophy, which were more severe compared with previous reports. In this patient, low-protein diet successfully reduced hyperammonemia, but hyperargininemia persisted. These severe neurological and MRI findings may be explained by a compound heterozygote, inheriting both of severe mutant alleles from her parents.

Background: Residual dried blood spots (DBS) remaining after routine newborn screening (NBS) tests are candidate specimens for extended uses such as quality assurance and the development of new technology. A trial of NBS using tandem mass-spectrometry was launched in 2004 in Japan. The aim of the present study was to analyze the attitudes of the public, patient families, and medical professionals toward the extended use and long-term storage of residual DBS, and to construct a standardized informational brochure. Methods: A questionnaire was sent to randomly selected members of the public, members of the Japanese Phenylketonuria (PKU) Association, medical staff of a general hospital, staff of a children's hospital, obstetricians and gynecologists, pediatricians and NBS personnel. Associated responses, which were given in a free comment format, were analyzed by text mining. Results: The awareness ratio of NBS was low in the public (26.6%), but despite this, when a brief explanatory note on NBS was provided, 71.7% of them recognized the necessity of NBS. They were less positive than medical professionals and PKU patient families regarding the extended use of DBS for forensic investigation, for the study of health problems, or long-term storage of residual DBS, regardless of whether these factors affected them personally or not. Among the medical professionals, obstetricians and pediatricians exhibited a higher ratio of negative responses toward the extended use and long-term storage of DBS than others. Conclusion: The general public is more conservative than PKU patients and their families or medical professionals about the extended use or long-term storage of residual DBS. Presentation to the public, particularly to couples of childbearing age, of appropriate explanatory information on NBS itself, or the extended use or long-term storage of residual DBS, is recommended.

Sulfonated polyimides (SPIs) derived from 1,4,5,8-naphthalene tetracarboxylic dianhydride, 4,4′-bis(4-aminophenoxy) biphenyl-3,3′-disulfonic acid and hydrophobic aromatic diamines showed the much lower methanol permeability and the lower proton conductivity than Nafion 112. The performance and the water and methanol crossover for direct methanol fuel cells (DMFCs) with the SPI membranes were investigated in comparison with Nafion membranes. The methanol and water fluxes increased significantly with increasing load current density for Nafion membranes but not for the SPI membranes, indicating that they were controlled by both the electro-osmotic drag and the molecular diffusion for the former but by only the molecular diffusion for the latter. These resulted in the much better DMFC performance for the SPIs than Nafion membranes especially at high methanol feed concentrations. The Faraday's efficiency and overall DMFC efficiency at 60 °C and 200 mA cm −2 for SPI membrane with IEC of 1.51 meq g −1 were 75% and 21%, respectively, at 5 wt.% methanol feed concentration, and 36% and 9.5%, respectively, at 20 wt.% methanol concentration. They were about two times and three times higher at 5 wt.% and 20 wt.% methanol concentrations, respectively, than those for Nafion 112. The short-term durability test for 300 h at 60 °C revealed no deterioration in the DMFC performance. The SPI membranes have high potential for DMFC applications at mediate temperatures (40–80 °C).

Background: Gaucher disease type 1 and type 3 are characterized by bone disease and hematological symptoms. It is known that monocyte/macrophage lineage is activated in Gaucher disease, and accordingly certain cytokines are elevated in blood. The aim of the present study was to explore the possible relationships between cytokines and bone remodeling and hematological abnormalities in this disease. Methods: The concentrations of seven cytokines and two related proteins were measured in patients with Gaucher disease type 1 and type 3 (n= 8; age range, 2–50 years) who had received enzyme replacement therapy. Results: Concentrations of interleukin-18 and transforming growth factor-β1 were elevated in patients of all clinical types. Elevation of these cytokines in Gaucher disease has not been previously reported. Analysis of correlation among cytokines and bone-turnover markers showed that interleukin-18 concentration was correlated with each of two bone formation markers of bone-specific alkaline phosphatase activity and osteocalcin concentration, whereas macrophage colony-stimulating factor concentration correlated with the bone absorption marker of N-telopeptide to helix in urine. Concentrations of macrophage colony-stimulating factor and tumor necrosis factor-α were inversely correlated with hemoglobin concentration. Conclusions: Interleukin-18 and monocyte macrophage colony-stimulating factor are cytokines mainly involved in the mechanism of bone disease, while macrophage colony-stimulating factor and tumor necrosis factor-α may play a role in the development of hematological abnormalities in Gaucher disease.

In ten families with late-onset ornithine transcarbamylase (OTC) deficiency in male patients, three mutant alleles-R40H, R277W, and Y55D-were identified. In a total of 20 informative parent-offspring pairs, father-to-daughter transmission and mother-to-offspring transmission occurred in five (25%) and 15 (75%), respectively, indicating that paternal transmission contributes substantially to the pool of these mutant alleles. Relative reproductive fitness of males and females carrying the mutant alleles was calculated to be 0.49 and 0.89, respectively. Comparison of the life span of the mutant alleles, estimated on the basis of these fitness values with those associated with classic phenotype (neonatal onset) in which reproductive fitness of male patients was nil, revealed that mutant alleles associated with the late-onset phenotype were eliminated more slowly. This would allow the late-onset phenotype mutant alleles to be retained more frequently in a population than those associated with classic phenotype. Although heterozygous females carrying the late-onset phenotype mutant alleles were generally asymptomatic, one female carrying the R40H allele died after a hyperammonemic episode at the age of 18 years. Such heterozygous females should be alerted to possible hyperammonemic crisis.

A series of star-like poly(ethylene oxide)s were synthesized using anhydride-terminated hyperbranched polyimides as the central cores and poly(ethylene oxide)s (PEOs) as the linear arms. Their physical and gas permeation properties were investigated in comparison with those of PEO segmented block copolyimides (PEO-PIs). The solubility of star-like PEOs was affected by the terminal groups. The amine-terminated star-like PEOs displayed better solubility property than the methoxy- and acetamido-terminated ones. The DSC and dynamic mechanical spectroscopy suggested the morphology of star-like PEOs was different from that of PEO-PIs. The thermo-mechanical property of amine-terminated star-like PEOs was significantly improved by cross-linking with ethylene glycol diglycidyl ether. The star-like PEO membranes were much more permeable to CO2 than to N2 and even to H2. However, their CO2 separation performance was slightly lower than that of PEO-PIs, probably due to the difference in the morphology. The AgBF4-doped star-like PEO membrane with a loading of 40 wt% (corresponding to 67 wt% in PEO matrix) showed a very high ideal selectivity of C2H4/C2H6 of more than 100 with a low ethylene permeability of 1.5×10−10 cm3 (STP) cm−1 s−1 cm Hg−1 in single-component permeation at 2 atm and 308 K. However, the permselectivity decreased down to 14 in mixed gas permeation. The permeation behavior was discussed based on the solubility and diffusivity.

We studied the effects of L-carnitine supplementation at a small dose on the profiles of acylcarnitines in serum and urine, as well as the renal handling of acylcarnitines, in a patient with multiple acyl-coenzyme A dehydrogenation defect. After supplementation with L-carnitine at a dose of 20 mg/kg/day, the concentration of each acylcarnitine measured both in the serum and in the urine had increased significantly, with the exception of that of an acylcarnitine with a carbon chain length (C) of 8 (C8 acylcarnitine). The magnitude of increase in the concentrations of the acylcarnitines in the serum was not associated with chain length, whereas in the urine, the magnitude tended to be greater in proportion to the shortness of the chain length. The fractional excretions of C2-C5 acylcarnitines exceeded 100%, indicating that they were produced in, or transported across, renal tubular epithelial cells and secreted into the urine. These results indicate that supplementation with a relatively small amount of L-carnitine can enhance the renal excretion of accumulated short-chain-length acylcarnitines through tubular excretion, in addition to basic glomerular filtration.

Classical citrullinemia (CTLN1), a rare autosomal recessive disorder, is caused by mutations of the argininosuccinate synthetase (ASS) gene, localized on chromosome 9q34.1. ASS functions as a rate-limiting enzyme in the urea cycle. Previously, we identified 32 mutations in the ASS gene of CTLN1 patients mainly in Japan and the United States, and to date 34 different mutations have been described in 50 families worldwide. In the present study, we report ASS mutations detected in 35 additional CTLN1 families from 11 countries. By analyzing the entire coding sequence and the intron-exon boundaries of the ASS gene using RT-PCR and/or genomic DNA-PCR, we have identified 16 novel mutations (two different 1-bp deletions, a 67-bp insertion, and 13 missense) and have detected 12 known mutations. Altogether, 50 different mutations (seven deletion, three splice site, one duplication, two nonsense, and 37 missense) in 85 CTLN1 families were identified. On the basis of primary sequence comparisons with the crystal structure of E. coli ASS protein, it may be concluded that any of the 37 missense mutations found at 30 different positions led to structural and functional impairments of the human ASS protein. It has been found that three mutations are particularly frequent: IVS6-2A>G in 23 families (Japan: 20 and Korea: three), G390R in 18 families (Turkey: six, U.S.: five, Spain: three, Israel: one, Austria: one, Canada: one, and Bolivia: one), and R304W in 10 families (Japan: nine and Turkey: one). Most mutations of the ASS gene are "private" and are distributed throughout the gene, except for exons 5 and 12-14. It seems that the clinical course of the patients with truncated mutations or the G390R mutation is early-onset/severe. The phenotype of the patients with certain missense mutations (G362V or W179R) is more late-onset/mild. Eight patients with R86H, A118T, R265H, or K310R mutations were adult/late-onset and four of them showed severe symptoms during pregnancy or postpartum. However, it is still difficult to prove the genotype-phenotype correlation, because many patients were compound heterozygotes (with two different mutations), lived in different environments at the time of diagnosis, and/or had several treatment regimes or various knowledge of the disease.

Effects of pyrolysis and preparation conditions on the gas permeation properties of pyrolytic membranes derived from sulfonated phenolic resin were investigated. Pyrolysis temperature, dip-coating conditions and coating/pyrolysis (C/P) cycle had significant influence on the gas permeation properties of pyrolytic membranes. Membrane obtained under optimum preparation conditions exhibited O 2 permeance of 30 GPU and ideal O 2 /N 2 separation factor of 12 at 35 °C, which are comparable to the O 2 /N 2 separation performances of carbon molecular sieve (CMS) membranes on the upper-bound line in the plots of permeance versus selectivity. N 2 adsorption and desorption at 77 K suggested that the pore structures of CMS membranes pyrolyzed around 500 °C seemed to be made up of interconnected pores with different size and shape.

Carbonized membranes were prepared by pyrolyzing an asymmetric hollow fiber membrane of a copolyimide from equimolar portion of 2,2-bis(3,4-dicarboxyphenyl)hexafluoro-propane dianhydride (6FDA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) with 3,7-diamino-2,8(6)-dimethyldibenzothiophene sulfone (DDBT) at temperatures of 773–973 K under a nitrogen stream. The carbonized membranes had an asymmetric structure with a skin layer of around 200 nm in thickness and a much denser support layer compared with the precursor hollow fiber. The increase in permeance to propylene R C 3 H 6 by the pyrolysis was up to 10 times. An appropriate holding time during the pyrolysis in a nitrogen stream tended to increase the olefin/paraffin selectivity. The membranes pyrolyzed at 813 K for 1 h displayed the best performance of R C 3 H 6 =26 GPU and α C 3 H 6 /C 3 H 8 =22 for mixed-component (50/50%) at 373 K and 1 atm. The effect of silicone rubber coating was also investigated.

Gas permeation properties of asymmetric hollow fiber membrane of copolyimide prepared from equimolar portion of 2,2-bis(3,4-dicarboxyphenyl)hexafluoropropane dianhydride (6FDA) and 3,3′,4,4′-biphenyltetracarboxylic dianhydride (BPDA) with 3,7-diamino-2,8(6)-dimethyldibenzothiophene sulfone (DDBT) were investigated for single-component light gases, olefins and paraffins and for mixed components of C3H6/C3H8 and C4H6/C4H10. The gas permeability of the copolyimide film was close to that of 6FDA–DDBT polyimide and much larger than that of BPDA–DDBT. Gas permeance of the asymmetric copolyimide hollow fiber membrane decreased significantly in the first several months and leveled off after about 10 months of aging. The skin layer thickness calculated from the gas permeability and permeance was in the range of 0.6 (for H2) to 1.7 μm (for C3H6) and about 10 times larger than the thickness estimated from the SEM observation. These results indicated that the significant densification of the skin layer was caused by physical aging. The silicone rubber coating hardly changed the selectivity for light gas pairs such as H2/CH4 and O2/N2, but enhanced that for C3H6/C3H8 and C4H6/C4H10 significantly especially at low temperatures. The evaluation of membrane quality based on the resistance model suggested that the extremely small surface porosity of defect pores significantly reduced the selectivity for the larger gas pairs. The asymmetric copolyimide hollow fiber membrane displayed better performance for C3H6/C3H8 and C4H6/C4H10: for example, permeances of C3H6 and C4H6 of 3.6 and 7.4 GPU, respectively, and separation factors of 15 and 69 for C3H6/C3H8 and C4H6/C4H10 (50/50 mol% in feed) at 373 K and 1 atm.

Two distinct human light subunits of the heteromeric amino acid transporter, y+LAT-1 coded by SLC7A7 and y+LAT-2 coded by SLC7A6, are both known to induce transport system y+L activity. SLC7A7 has already been identified as the gene responsible for lysinuric protein intolerance (LPI). We successfully identified five novel SLC7A7 variants (S238F, S489P, 1630delC, 1673delG, and IVS3-IVS5del9.7kb) in Japanese patients with LPI by PCR amplification and direct DNA sequencing. In addition, we performed a semi-quantitative expression analysis of SLC7A7 and SLC7A6 in human tissue. In normal tissue, the gene-expression ratio of SLC7A6 to SLC7A7 was high in the brain, muscle, and cultured skin fibroblasts; low in the kidneys and small intestine; and at an intermediate level in peripheral blood leukocytes, the lungs, and cultured lymphoblasts. The gene-expression ratio of SLC7A6 to SLC7A7 in cultured lymphoblasts was significantly different between normal subjects and LPI patients with R410X and/or S238F, where the relative amount of SLC7A7 mRNA was significantly lower and the relative amount of SLC7A6 mRNA was statistically higher in affected lymphoblasts than in normal cells. Expression of SLC7A7 and SLC7A6 may thus be interrelated in cultured lymphoblasts. Hum Mutat 20:375–381, 2002. © 2002 Wiley-Liss, Inc.

Carbon molecular sieving membranes were prepared by pyrolysis of lignocresol derived from lignin by the phase-separation method. Lignocresol membranes formed by a dip process on a porous α-alumina tubing were carbonized at 400–800°C under nitrogen atmosphere. The thickness of the membrane formed on the outer surface of the substrate was about 400 nm judging from SEM observation. Gas-evolving behavior of lignocresol was measured using thermogravimetry-mass spectrometry (TG-MS). The gaseous products evolved from lignocresol included a number of fragments with higher molecular weights; whereas those from phenolic resin are mainly due to phenol and methylphenol. These evolved pyrolysis fragments effectively contribute to micropore formation of carbonized lignocresol membranes. Gas permeation rates through the membrane decreased in the order of increasing kinetic molecular diameter of the penetrant gas, and the membrane behaved like a “molecular sieve.” The permeation properties were dependent on heating conditions, and a pyrolysis temperature of 600°C gave the best membrane performance. Gas selectivities of the membrane prepared at 600°C were 50, 8, 290, and 87 for CO2/N2, O2/N2, H2/CH4, and CO2/CH4 at 35°C, respectively.

A thermosetting phenolic resin with a pendant sulfonic acid group was prepared by reacting a resol-type phenolic resin (PF) with a Novalak-type sulfonated phenolic resin (SPF). Large amounts of gaseous molecules with similar and small size such as H2O and SO2 evolved in the range of 110 and 350 °C during the pyrolysis of this thermosetting phenolic resin (PF/SPF). Highly permeable carbon molecular sieve (CMS) membranes were obtained by pyrolysis of PF/SPF(45/55) precursor membranes which were dip-coated on porous alumina tubes. For example, the membrane pyrolyzed at 500 °C for 1.5 h displayed H2, CO2, and O2 permeances of 1950, 800, and 240 [GPU (gas permeation units) = 10-6 cm3(STP)·s-1·cm-2·cmHg-1], respectively, and ideal H2/CH4, CO2/CH4, and O2/N2 separation factors of 65, 27, and 5.2 at 35 °C and 1 atm, respectively. Sulfonic acid groups linked to thermostable polymer chains might act as “bonded templates” and showed attractive potential in the preparation of CMS membranes.

3-Methylcrotonyl-CoA carboxylase (MCCase; EC 6.4.1.4) is a mitochondrial biotin enzyme and plays an essential role in the catabolism of leucine and isovalerate in animals, bacterial species, and plants. MCCase consists of two subunits, those that are biotin-containing and non-biotin-containing. The genes responsible for these subunits have been isolated in soybean, Arabidopsis thaliana, and tomatoes, but not in mammals. In humans, MCCase deficiency has been thought to be a rare metabolic disease, but the number of patients with MCCase deficiency appears to be increasing with a wide range of clinical presentations, some that result in a lethal condition and others that are asymptomatic. In this report, we have isolated and carried out chromosomal mapping of the gene for the biotin-containing subunit (A subunit) of the human MCCase gene, MCCA. The cDNA predicts an open reading frame coding for a 725-amino-acid protein with mitochondrial signal peptide, biotin carboxylase, and biotin-carrier domains. The gene is composed of at least 19 exons and covers more than 70 kb of sequence on band q27 of chromosome 3. MCCA was abundantly expressed in mitochondria-rich organs, such as the heart, skeletal muscles, kidney, and liver. In exon 13, we observed a His/Pro polymorphism at codon 464 (an A to C transition at nucleotide position 1391 in the cDNA sequence). Then, we determined the DNA sequences of the 5' untranslated region and entire coding regions in two patients with MCCase deficiency, but no sequence substitution was detected, suggesting that the gene mutations might be in the non-biotin-containing subunit (B subunit) gene, MCCB, in these patients.

Carbonized hollow fiber membranes were prepared by pyrolyzing an asymmetric hollow fiber membrane of a polyimide from 3,3‘,4,4‘-biphenyltetracarboxylic dianhydride and aromatic diamines at temperatures of 500−700 °C under a nitrogen stream. The precursor membrane was treated in air at 400 °C for 0.5 h before the pyrolysis. This pretreatment was effective for improvement of gas permeance of the carbonized membranes. The carbonized membranes had an asymmetric structure with a skin layer of around 200 nm in thickness. They had the characteristics of larger permeance and lower permselectivity for inorganic gas pairs such as O2/N2, but this was rather preferable to the separation of olefin/paraffin. The membranes pyrolyzed at 600−630 °C displayed good stability and excellent performances of propylene/propane and 1,3-butadiene/n-butane separation based on the molecular sieving.

We report the case of a family with late-onset ornithine transcarbamylase deficiency (OTCD). Several family members had died from OTCD, and the c.221GA, p.Lys221Lys mutation was detected at the 3' end of exon 6 of OTC in the X-chromosome of some members. We provided genetic counseling on pregnancy, delivery, and neonate management to a 4th-generation female carrier and decided on metabolic management of her child from birth. Two male patients were diagnosed with late-onset OTCD on the basis of blood amino acid and genetic analysis, and they received arginine supplementation from the asymptomatic, early neonatal period. These children grew and developed normally, without decompensation. Patients with late-onset OTCD can and should be diagnosed and treated in the early neonatal period, especially those from families already diagnosed with late-onset OTCD, and family members must be provided with genetic counseling.

The late-onset type of ornithine transcarbamylase (OTC) deficiency is almost asymptomatic before an abrupt onset of metabolic crisis in adolescence. This study focused on coagulopathy in OTC deficiency. We collected laboratory data regarding coagulation from OTC-deficient patients in Kyushu University Hospital in Japan or from cases reported from previous articles. Five patients with late-onset OTC deficiency, admitted to Kyushu University Hospital at the first metabolic attack or who presented at the outpatient clinic in the hospital, were analyzed, and 3 additional cases of OTC deficiency with coagulopathy in previous articles were included. As a result, the blood ammonia levels in these patients were remarkably high at the time of the metabolic attack, and prothrombin times were far below the normal level. The prothrombin times remained significantly abnormal on remission, despite almost normal levels of blood ammonia, serum aspartate aminotransferase, and alanine aminotransferase. Coagulation abnormality is a previously unidentified complication of OTC deficiency in remission state. This information will aid in the identification of patients with OTC deficiency before a lethal metabolic crisis occurs during adolescence.

A 36-year-old man with mucolipidosis type III alpha/beta presented with hypoactivity, mutism, muscle rigidity, and involuntary movement. The involuntary movement was interpreted to be tremor at rest on physical examination and surface electromyography, which revealed mostly asynchronous contractions at 3-4 Hz of the biceps and triceps brachii muscles. All these symptoms were consistent with abnormalities of parkinsonism, which is caused by an insult to the basal ganglia that permeates the entire basal ganglia-thalamocortical circuitry. This report is the first to present a case of mucolipidosis type III alpha/beta in association with parkinsonism.

In 4 young pediatric patients with presymptomatic Wilson disease, we found zinc monotherapy beginning at time of diagnosis to be safe and highly effective for follow-up intervals between 1 and 2 years. Such maintenance therapy with zinc can maintain urinary copper excretion between 1 and 3 μg · kg(-1) · day.

Few studies have looked at optimal or acceptable serum phenylalanine levels in later life in patients with phenylketonuria (PKU). This study examined the oxidative stress status of adolescents and adults with PKU. Forty PKU patients aged over fifteen years were enrolled, and were compared with thirty age-matched controls. Oxidative stress markers, anti-oxidant enzyme activities in erythrocytes, and blood anti-oxidant levels were examined. Nitric oxide (NO) production was also examined as a measure of oxidative stress. Plasma thiobarbituric acid reactive species and serum malondialdehyde-modified LDL levels were significantly higher in PKU patients than control subjects, and correlated significantly with serum phenylalanine level (P

Recent studies suggest that refractory hypotension from causes other than septicaemia or cardiac failure is common in extremely preterm infants even out of the transitional period. Marked response to low-dose cortisol suggests underlying adrenal insufficiency, although the exact mechanism remains unknown.To investigate potential triggers for and related short-term outcomes of early-onset (Day 7) and late-onset (≥Day 7) refractory hypotension, clinical data for 70 infants30 weeks gestation were assessed.The incidence of early-onset refractory hypotension (n=7) was correlated with younger gestational ages26 weeks (P0.05), whereas the incidence of late-onset refractory hypotension (n=14) was correlated with younger gestational ages and levothyroxine supplementation (P0.05 and 0.01, respectively). The incidence of both early- and late-onset refractory hypotension was correlated with risks of short-term adverse outcomes such as prolonged mechanical ventilation and hospital stay.Levothyroxine supplementation was identified as an independent variable correlated with an increased incidence of refractory hypotension out of the transitional period; as seen in hypothyroidism with Addison's disease, the immature hypothalamic-pituitary-adrenal axis may not respond properly to the increased demand for cortisol, which may precipitate premature infants into refractory hypotension. Following the administration of levothyroxine, preterm infants may have to be carefully monitored for early signs of refractory hypotension.

Introduction Ornithine transcarbamylase deficiency is the most common hereditary urea cycle defect. It is inherited in an X-linked manner and classically presents in neonates with encephalopathy and hyperammonemia in males. Females and males with hypomorphic mutations present later, sometimes in adulthood, with episodes that are frequently fatal. Case presentation A 13-year-old Caucasian girl presented with progressive encephalopathy, hyperammonemic coma and lactic acidosis. She had a history of intermittent regular episodes of nausea and vomiting from seven years of age, previously diagnosed as abdominal migraines. At presentation she was hyperammonemic (ammonia 477 μmol/L) with no other biochemical indicators of hepatic dysfunction or damage and had grossly elevated urinary orotate (orotate/creatinine ratio 1.866 μmol/mmol creatinine, reference range A) mutation was identified in the ornithine transcarbamylase gene (OTC) in our patient confirming the first symptomatic female shown heterozygous for the R40H mutation. A review of the literature and correspondence with authors of patients with the R40H mutation identified one other symptomatic female patient who died of hyperammonemic coma in her late teens. Conclusions This report expands the clinical spectrum of presentation of ornithine transcarbamylase deficiency to female heterozygotes for the hypomorphic R40H OTC mutation. Although this mutation is usually associated with a mild phenotype, females with this mutation can present with acute decompensation, which can be fatal. Ornithine transcarbamylase deficiency should be considered in the differential diagnosis of unexplained acute confusion, even without a suggestive family history.

A connection between LEOPARD syndrome (a rare autosomal dominant disorder) and autism spectrum disorders (ASDs) may exist. Of four related individuals (father and three sons) with LEOPARD syndrome, all patients exhibited clinical symptoms consistent with ASDs. Findings included aggressive behavior and impairment of social interaction, communication, and range of interests. The coexistence of LEOPARD syndrome and ASDs in the related individuals may be an incidental familial event or indicative that ASDs is associated with LEOPARD syndrome. There have been no other independent reports of the association of LEOPARD syndrome and ASDs. Molecular and biochemical mechanisms that may suggest a connection between LEOPARD syndrome and ASDs are discussed.

Issues pertinent to patients with phenylketonuria(PKU) in adulthood are presented. Nutritional management policy that is optimal to prevent such nutritional complications as osteoporosis and possible vitamin B12 deficiency in each age group should be considered. Adolescent girls with PKU and their guardians should be informed of the issue of maternal PKU to prevent the condition. Socioeconomical issues also remain to be solved. Most adult patients have felt that medical expense to continue dietary therapy is a significant economical burden, which often leads to withdrawal from the therapy. Buying life insurance may be refused by insurance companies simply because the patients have PKU. Current knowledge on health status of well-controlled PKU patients should be provided to insurance companies.

Wilson disease is an autosomal recessive disorder with copper metabolism. In Japan, the standard treatment is the administration of copper chelating agents, such as D-penicillamine and trientine. In this study, the authors used zinc acetate to treat Japanese patients with Wilson disease and investigated its efficacy. The 37 patients that comprise this study were found to have Wilson disease using clinical and biochemical tests and were administrated zinc acetate for 48 weeks. The authors followed the clinical symptoms and laboratory findings of the patients by assessing their complete blood counts, biochemical findings, as well as the results of urinalysis and special laboratory tests for copper and zinc metabolism. We also examined side effects of the treatment. Zinc acetate did not aggravate the hepatic or neurological symptoms of any of the patients. Blood biochemical analysis also did not reveal elevation of alanine aminotransferase, aspartate aminotransferase, and γ-glutamyltranspeptidase levels. Zinc treatment did not aggravate the patients' clinical signs and/or laboratory findings. However, it did improve some clinical symptoms of the Wilson disease patients. Although this agent had some side effects, none of them were severe. The authors measured spot urinary copper excretion, which gave an indication of the efficacy of treatment and of the sufficient dosage of zinc. We recommend maintaining a spot urinary copper excretion less than 0.075-μg/mg creatinine. The authors conclude that zinc acetate is an effective and safe treatment for Japanese patients with Wilson disease.

To better understand the biosynthesis of guanidinosuccinic acid, we determined urea, arginine, and guanidinosuccinic acid levels in nondialyzed uremic and hyperargininemic patients. These substances were also determined during several years of therapy in one hyperarginiemic patient. Interrelationships of guanidinosuccinic acid levels with their corresponding urea and arginine levels were assessed by linear correlation studies. In uremic patients, a significant positive linear correlation (r = .821, p less than .001) was found between serum urea and guanidinosuccinic acid levels A significant positive linear correlation was also found between serum urea levels and urinary guanidinosuccinic acid levels (r = .828, P less than .001), but not between serum arginine levels and urinary guanidinosuccinic acid levels in hyperargininemic patients. In the intrahyperargininemic patient study, a similar significant positive correlation was found between serum urea levels and the corresponding urinary guanidinosuccinic acid levels (r = .866, P less than .001); the correlation between serum arginine levels and the corresponding urinary guanidinosuccinic acid levels was smaller. The presented analytical findings in uremic and hyperargininemic patients clearly demonstrate a metabolic relationship between urea and guanidinosuccinic acid.

Wilson's disease is an autosomal recessive disorder characterized by an accumulation of a toxic amount of copper in the body. Triethylene tetramine dihydrochloride (trientine, 2HCl) is a new chelating agent that may be effective in the removal of excess copper but long-term efficacy has not yet been investigated. Here we report the use of trientine over more than 8 years in 2 patients with Wilson's disease who could not tolerate D-penicillamine. We found no significant side effect, except a decreased serum iron concentration without clinical symptoms of anemia. In annual examinations at a steady state, the serum copper levels remained below 20 micrograms/100 ml. The 24-hour urinary copper excretion was less than that found using D-penicillamine, while the basal copper excretion, after 5 days abstinence from trientine, was maintained below 100 micrograms/day. Both hepatic and neurological manifestations except bulbar symptoms were recovered without any initial deterioration.

Serum transthyretin has several isoforms, most of which are caused by disulfide linkage with cysteine residue at position 10. We found an ion peak 80 D larger than unmodified transthyretin by electrospray ionization mass spectrometry and assigned it to S-sulfonated transthyretin. The peak height was

Osteoporosis-pseudoglioma syndrome (OPS; OMIM 259770) is an autosomal-recessive genetic disorder characterized by severe osteoporosis and visual disturbance from childhood. Biallelic mutations in the low-density lipoprotein receptor-related protein 5 gene (LRP5) have been frequently detected, while a subset of patients had only one or no detectable mutation. We report on the clinical and molecular findings of four unrelated Japanese patients with the syndrome. The four patients had typical skeletal and ocular phenotypes of OPS, namely severe juvenile osteoporosis and early-onset visual disturbance, with or without mental retardation. We undertook standard PCR-based sequencing for LRP5 and found four missense mutations (p.L145F, p.T244M, p.P382L, and p.T552M), one nonsense mutation (p.R1534X), and one splice site mutation (c.1584+1G>A) among four OPS patients. Although three patients had two heterozygous mutations, one had only one heterozygous splice site mutation. In this patient, RT-PCR from lymphocytic RNA demonstrated splice error resulting in 63-bp insertion between exons 7 and 8. Furthermore, the patient was found to have only mutated RT-PCR fragment, implying that a seemingly normal allele did not express LRP5 mRNA. We then conducted custom- designed oligonucleotide tiling microarray analyses targeted to a 600-kb genome region harboring LRP5 and discovered a 7.2-kb microdeletion encompassing exons 22 and 23 of LRP5. We found various types of LRP5 mutations, including an exon-level deletion that is undetectable by standard PCR-based mutation screening. Oligonucleotide tiling microarray seems to be a powerful tool in identifying cryptic structural mutations.