Characteristics of successful termination of atrial fibrillation by atrial antitachycardia pacing in patients with cardiac implantable electronic devices

Asymptomatic paroxysmal atrial fibrillation (AF) is often found in patients implanted with cardiac implantable electronic devices (CIEDs). Second-generation atrial antitachycardia pacing (A-ATP) is effective in managing AF in patients implanted with CIEDs. The purpose of this study was to evaluate the efficacy and safety of A-ATP in patients implanted with CIEDs. This was a single-center retrospective study involving 91 patients (male 46 patients, mean age 74 ± 9 years) implanted with Reactive A-ATP equipped devices (84 patients with pacemakers, 6 with ICDs, and 1 with a CRT-D). The AF burden, rate of AF termination, and details of the activation of the A-ATP were analyzed in each patient. During a mean follow-up period of 21 ± 13 months, A-ATP was activated in 45 of 91 patients (49.5%). No patients had adverse events. Although the efficacy of the A-ATP varied among the patients, the median rate of AF termination was 44%. In comparison to the A-ATP start time, "0 min" had a higher AF termination rate by the A-ATP (39.4% vs. 24.4%, P = 0.011). The rate of termination by the A-ATP was high for AF with a long cycle length and a relatively regular rhythm. A-ATP successfully terminated AF episodes in some patients implanted with CIEDs. The optimal settings of the A-ATP will be determined in future studies.

Erratum: Quadrupole Order in the Frustrated Pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y} [Phys. Rev. Lett. 116, 217201 (2016)]

This corrects the article DOI: 10.1103/PhysRevLett.116.217201.

Protective action of the microbial metabolite butyrate against cardiomyocyte hypertrophy

Introduction

Short-chain fatty acids are one of the gut microbial metabolites that may influence host physiology. We previously reported that gut dysbiosis was associated with heart failure, and that the proportions of butyrate-producing bacteria diminished prominently in the gut of patients with heart failure.

Purpose

We investigated the molecular mechanism of butyrate and investigated the protective mechanism against heart failure.

Methods

We searched for G protein-coupled receptors for short-chain fatty acids using single-cell transcriptome analysis of cardiomyocytes and non-cardiomyocytes isolated from murine hearts. In addition, we examined the effects of butyrate on endothelin-1 (ET1) or isoproterenol-induced hypertrophic responses and histone deacetylase (HDAC) activities in cultured neonatal rat cardiomyocytes.

Results

Single-cell transcriptome analysis and co-expression network analysis revealed that G protein-coupled receptors for short-chain fatty acid receptors were not expressed in cardiomyocytes and that Olfr78 was expressed in vascular smooth muscle cells in the heart. Treatment with butyrate inhibited ET1-induced hypertrophic growth and up-regulation of the genes such as Nppa, Acta1, and Myh7 in cultured rat neonatal cardiomyocytes. Moreover, butyrate increased the acetylation levels of histone H3, indicating that butyrate has an inhibitory effect on HDAC in cardiomyocytes. In addition, treatment with butyrate caused up-regulation of Inpp5f, encoding inositol polyphosphate-5-phosphatase f, which was associated with a significant decrease in the phosphorylation levels of Akt. These results suggest that butyrate may act as HDAC inhibitor to increase Inpp5f gene expression, leading to the activation of Akt-glycogen synthase kinase 3beta (Gsk3beta) pathway, and thereby protect against hypertrophic responses.

Conclusion

There was no known GPCR for short-chain fatty acid expressed in cardiomyocytes. However, butyrate suppressed cardiomyocyte hypertrophy through epigenetic modification of gene expression. Our results may uncover a potential role of the dysbiosis of intestinal microbiota in the pathogenesis of cardiac hypertrophy and failure.

Funding Acknowledgement

Type of funding source: None

Persistent high blood urea nitrogen level is associated with increased risk of cardiovascular events in patients with acute heart failure

Aims

The association between kinetics of blood urea nitrogen (BUN) levels in hospital and cardiovascular outcomes in patients with acutely decompensated congestive heart failure (HF) is unclear. We aimed to estimate the impact of changes in BUN level during hospitalization on clinical prognosis in patients with acute HF.

Methods and results

A total of 353 consecutive patients that were urgently hospitalized due to acutely decompensated HF and discharged alive were divided into four subgroups depending on their BUN level at admission and discharge, using a cut‐off level of 21.0 mg/dL. Among 206 patients with high baseline BUN level, 46 (22%) and 160 (78%) had normal and persistent high BUN levels at discharge, respectively. In contrast, of the 147 patients with normal baseline BUN level, 55 (37%) and 92 (63%) had high and normal BUN levels at discharge, respectively. During the observational period after discharge, Kaplan–Meier analysis showed the highest rate of combined outcome of cardiovascular death and HF readmission in patients with persistent high BUN (log‐rank test: P < 0.001). After adjustment for comorbidities, the hazard ratio for a combined outcome was significantly lower in patients with normalized BUN level compared with those with persistent high BUN (hazard ratio 0.48, 95% confidence interval 0.23–0.99, P = 0.049).

Conclusions

Persistent high BUN levels in hospital are associated with an increased risk of cardiovascular death and HF readmission. Normalization of BUN levels during hospitalization may be associated with long‐term clinical outcomes.

Quadrupole Order in the Frustrated Pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y}

A hidden order that emerges in the frustrated pyrochlore Tb_{2+x}Ti_{2-x}O_{7+y} with T_{c}=0.53  K is studied using specific heat, magnetization, and neutron scattering experiments on a high-quality single crystal. Semiquantitative analyses based on a pseudospin-1/2 Hamiltonian for ionic non-Kramers magnetic doublets demonstrate that it is an ordered state of electric quadrupole moments. The elusive spin liquid state of the nominal Tb_{2}Ti_{2}O_{7} is most likely a U(1) quantum spin-liquid state.

A genome-wide scan for quantitative trait loci affecting respiratory disease and immune capacity in Landrace pigs

Respiratory disease is the most important health concern for the swine industry. Genetic improvement for disease resistance is challenging because of the difficulty in obtaining good phenotypes related with disease resistance; however, identification of genes or markers associated with disease resistance can help in the genetic improvement of pig health. The purpose of our study was to investigate whether quantitative trait loci (QTL) associated with disease resistance were segregated in a purebred population of Landrace pigs that had been selected for meat production traits and mycoplasmal pneumonia of swine (MPS) scores over five generations. We analysed 1395 pigs from the base to the fifth generation of this population. Two respiratory disease traits [MPS scores and atrophic rhinitis (AR) scores] and 11 immune-capacity traits were measured in 630-1332 animals at 7 weeks of age and when the animal's body weight reached 105 kg. Each of the pigs, except sires in the base population, was genotyped using 109 microsatellite markers, and then, QTL analysis of the full-sib family population with a multi-generational pedigree structure was performed. Variance component analysis was used to detect QTL associated with MPS or AR scores, and the logarithm of odds (LOD) score and genotypic heritability of the QTL were estimated. Five significant (LOD > 2.51) and 18 suggestive (LOD > 1.35) QTL for respiratory disease traits and immune-capacity traits were detected. The significant QTL for Log-MPS score, located on S. scrofa chromosome 2, could explain 87% of the genetic variance of this score in this analysis. This is the first report of QTL associated with respiratory disease lesions.

Fine mapping of porcine SSC14 QTL and SCD gene effects on fatty acid composition and melting point of fat in a Duroc purebred population

The stearoyl-CoA desaturase (delta-9-desaturase; SCD) gene is a candidate gene for fatty acid composition. It is located on pig SSC14 in a region where quantitative trait loci (QTL) for fatty acid composition were previously detected in a Duroc purebred population. The objective of the present study was to fine map the QTL, to identify polymorphisms of the pig SCD gene and to examine the effects of SCD polymorphisms on fatty acid composition and melting point of fat in the population. The pigs were examined for fatty acid composition and melting point of inner and outer subcutaneous fat and inter- and intramuscular fat; the number of pigs examined was 479-521. Two SNPs (g.-353C>T and g.-233T>C) were identified in the promoter region of the SCD gene and were completely linked in the pigs from the base generation. In all pigs, 19 microsatellite markers and SCD haplotypes were then genotyped. Different statistical models were applied to evaluate the effects of QTL and the possible causality of the SCD gene variants with respect to the QTL. The results show that all significant QTL for C14:0, C18:0, C18:1 and melting point of fat were detected in the same region, located near the SCD gene. The results also show a significant association between SCD haplotypes and fatty acid composition and fat melting point in this population. These results indicate that the haplotype of the SCD gene has a strong effect on fatty acid composition and melting point of fat.

Genome-wide mapping and identification of new quantitative trait loci affecting meat production, meat quality, and carcass traits within a Duroc purebred population

Most QTL detection studies in pigs have been carried out in experimental F(2) populations. However, segregation of a QTL must be confirmed within a purebred population for successful implementation of marker-assisted selection. Previously, QTL for meat quality and carcass traits were detected on SSC 7 in a Duroc purebred population. The objectives of the present study were to carry out a whole-genome QTL analysis (except for SSC 7) for meat production, meat quality, and carcass traits and to confirm the presence of segregating QTL in a Duroc purebred population. One thousand and four Duroc pigs were studied from base to seventh generation; the pigs comprised 1 closed population of a complex multigenerational pedigree such that all individuals were related. The pigs were evaluated for 6 growth traits, 7 body size traits, 8 carcass traits, 2 physiological traits, and 11 meat quality traits, and the number of pigs with phenotypes ranged from 421 to 953. A total of 119 markers were genotyped and then used for QTL analysis. We utilized a pedigree-based, multipoint variance components approach to test for linkage between QTL and the phenotypic values using a maximum likelihood method; the logarithm of odds score and QTL genotypic heritability were estimated. A total of 42 QTL with suggestive linkages and 3 QTL with significant linkages for 26 traits were detected. These included selection traits such as daily BW gain, backfat thickness, loin eye muscle area, and intramuscular fat content as well as correlated traits such as body size and meat quality traits. The present study disclosed QTL affecting growth, body size, and carcass, physiological, and meat quality traits in a Duroc purebred population.

11C-methionine PET of acute myocardial infarction

Tissue uptake of l-[methyl-(11)C]-methionine ((11)C-methionine) has been used to monitor amino acid metabolism and protein synthesis. We examined whether (11)C-methionine was retained in areas of myocardial infarction after successful reperfusion.

METHODS

Nine patients with infarction in the left anterior descendent region underwent percutaneous transluminal coronary artery intervention within 24 h and (201)Tl SPECT, (18)F-FDG PET, and (11)C-methionine PET within 2 wk of infarction onset. The standardized uptake values of the infarcted area and of the normal area were measured.

RESULTS

The (11)C-methionine images showed increased uptake in the infarcted area, whereas the (201)Tl SPECT and (18)F-FDG PET images showed decreased uptake. The highest accumulation of (11)C-methionine in the infarcted area was observed during the early phase of AMI.

CONCLUSION

(11)C-methionine uptake is elevated in infarcted areas and may reflect the early acute phase of damage healing, that is, the initial process of remodeling.

Genetic correlations among carcass cross-sectional fat area ratios, production traits, intramuscular fat, and serum leptin concentration in Duroc pigs

Animals accumulate fat in tissues as subcutaneous, intermuscular, intramuscular, and abdominal fat. Genetic interrelationships of respective fat depositions, however, have not been examined in depth. This study estimated genetic parameters for subcutaneous, intermuscular, and abdominal fat areas of 545 Duroc purebred pigs slaughtered at 105 kg of BW. Measurements were obtained using an image analysis system for positions between the 5th and the 6th thoracic vertebra (56TV), at half body length (HBL), and at the last thoracic vertebra (LTV) of the carcass. Moreover, serum leptin, which is a hormone product that is synthesized and predominantly expressed by adipocytes, was measured to determine if serum concentrations of leptin are useful as physiological predictors of fat accumulation in pigs. The heritability estimate of all fat area percentage at the HBL (0.70 +/- 0.03) was significantly greater than at the 56TV (0.53 +/- 0.03) or the LTV (0.55 +/- 0.04). Furthermore, the heritability estimate of subcutaneous fat areas at the HBL (0.71 +/- 0.04) was greater than at the 56TV (0.56 +/- 0.04) or LTV (0.60 +/- 0.03). Moreover, high heritabilities were estimated for ultrasound backfat thickness (BF; 0.72 +/- 0.03) on the left side at the position of HBL, intramuscular fat content of the loin (0.51 +/- 0.03), the seam fat score (SFS; 0.49 +/- 0.04), and the serum leptin concentration (0.62 +/- 0.05). Increased genetic correlations of BF with the fat area percentage of subcutaneous fat and all fat at 56TV (0.90 +/- 0.03 and 0.91 +/- 0.03), at HBL (0.88 +/- 0.03 and 0.94 +/- 0.01), and at LTV (0.88 +/- 0.03 and 0.90 +/- 0.02) were estimated. The genetic correlations of serum leptin concentration with the percentage of subcutaneous fat area and all fat areas at each position were also high (0.72 to 0.82 and 0.83 to 0.84, respectively). These results suggest that BF and leptin are good indicators of selection for decreasing fat deposition. Increased genetic correlation of the SFS with intermuscular fat area at 56TV (0.74) suggests that SFS is an effective indicator for decreasing intermuscular fat. The genetic correlation between the leptin concentration and feed conversion ratio was high (0.75 +/- 0.04). Results of this study indicate that the combination of BF and serum leptin concentration is a valuable indicator that can be incorporated into selection programs to improve carcass quality and feed efficiency in pigs.

Genetic parameters for feed efficiency traits and their relationships with growth and carcass traits in Duroc pigs

Genetic parameters for feed efficiency traits of 380 boars and growth and carcass traits of 1642 pigs (380 boars, 868 gilts and 394 barrows) in seven generations of Duroc population were estimated. Feed efficiency traits included the feed conversion ratio (FCR), and nutritional (RFI(nut)), phenotypic (RFI(phe)) and genetic (RFI(gen)) residual feed intake. Growth and carcass traits were the age to reach 105-kg body weight (A105), loin eye muscle area (EMA), backfat (BF), intra-muscular fat (IMF) and meat tenderness. The mean values for RFI(phe) and RFI(gen) were close to zero and for RFI(nut) was negative. All the measures of feed efficiency were moderately heritable (h(2) = 0.31, 0.38, 0.40 and 0.27 for RFI(nut), RFI(phe), RFI(gen) and FCR respectively). The heritabilities for all growth and carcass traits were moderate (ranged from 0.37 to 0.45), except for BF, which was high (0.72). The genetic correlations of RFI(phe) and RFI(gen) with A105 were positive and high. Measures of RFI were correlated negatively with EMA. BF was more strongly correlated with measures of RFI (r(g) > or = 0.73) than with FCR (r(g) = 0.52). Selection for daily gain, EMA, BF and IMF caused favourable genetic changes in feed efficiency traits. Results of this study indicate that selection against either RFI(phe) or RFI(gen) would give a similar correlated response in carcass traits.

Genetic parameters for measures of the efficiency of gain of boars and the genetic relationships with its component traits in Duroc pigs

Genetic parameters for the efficiency of gain traits on 380 boars and the genetic relationships with component traits were estimated in 1,642 pigs (380 boars, 868 gilts, and 394 barrows) in 7 generations of a Duroc population. The efficiency of gain traits included the feed conversion ratio (FCR) and residual feed intake (RFI) and their component traits, ADG, metabolic BW (MWT), and daily feed intake (FI). The RFI was calculated as the difference between the actual and expected FI. The expected FI was predicted by the nutritional requirement and by the residual of phenotypic (RFI(phe)) and genetic (RFI(gen)) regressions from the multivariate analysis for FI on MWT and ADG. The means for RFI(phe) and RFI(gen) were close to zero, and the mean for nutritional RFI was negative (-0.11 kg/d). The traits studied were moderately heritable (ranging from 0.27 to 0.53). The genetic and phenotypic correlations between ADG and FI were moderate to high, whereas the genetic correlation between MWT and FI was moderate, and the phenotypic correlation between them was low. The corresponding correlations between RFI(phe) and RFI(gen) were > 0.95, implying that they can be regarded as the same trait. The genetic and phenotypic correlations of FCR with measures of RFI were high but lower than unity. The RFI(phe) was phenotypically independent of its component traits, MWT (r(p) = 0.01) and ADG (r(p) = 0.03). The RFI(gen) was genetically independent of MWT (r(g) = -0.04), whereas there was a weak genetic relationship (r(g) = 0.15) between RFI(gen) and ADG. Residual FI was more heritable than FCR, and the genetic and phenotypic correlations of RFI(phe) and RFI(gen) with FI were positive and stronger than that of FCR with FI. These results provide evidence that RFI(phe) or RFI(gen) should be included in breeding programs for Duroc pigs to make genetic improvement in the efficiency of gain.

Kagomé ice state in the dipolar spin ice Dy2Ti2O7

We have investigated the kagomé ice behavior of the dipolar spin-ice compound Dy2Ti2O7 in a magnetic field along a [111] direction using neutron scattering and Monte Carlo simulations. The spin correlations show that the kagomé ice behavior predicted for the nearest-neighbor interacting model, where the field induces dimensional reduction and spins are frustrated in each two-dimensional kagomé lattice, occurs in the dipole interacting system. The spins freeze at low temperatures within the macroscopically degenerate ground states of the nearest-neighbor model.

Genetic correlations among fatty acid compositions in different sites of fat tissues, meat production, and meat quality traits in Duroc pigs

This study estimated genetic parameters for fatty acids of different sites of fat tissue, meat production, and meat quality traits of Duroc pigs selected during 7 generations for ADG, LM area, backfat thickness (BF), and intramuscular fat (IMF). For this study, 394 barrows and 153 gilts were slaughtered at 105 kg of BW. High heritabilities for C18:0 of outer and inner subcutaneous fat tissue were estimated, respectively, as 0.54 and 0.51; those of intermuscular and intramuscular fat were 0.40 and 0.51, respectively. Genetic and phenotypic correlations of ADG and BF with saturated fatty acids of outer and inner subcutaneous fat were positive, but those with C16:1 and C18:2 were negative, and those with C18:1 were nearly zero. Genetic and phenotypic correlations between LM area and respective fatty acids showed opposite results. Respective genetic and phenotypic correlations of melting points with C18:0 and C18:1 were positive and high, and negative and high, respectively. Genetic correlations between cooking loss and SFA (C14:0, C16:0, and C18:0) of IMF were positive and moderate: 0.56, 0.47, and 0.47, respectively. On the other hand, monosaturated fatty acid of C18:1 was highly and negatively correlated with cooking loss (-0.61). Moreover, high genetic correlation between meat color (pork color standard and lightness) and fatty acid compositions of IMF suggest that the SFA (C14:0, C16:0, and C18:0) were correlated genetically with meat lightness and that unsaturated fatty acid compositions (C18:1 and C18:2) were correlated with meat darkness. Results of this study suggest that the fatty acid composition of adipose tissue is correlated genetically with meat production and meat quality traits.

Photocatalytic Activity of the RuO2-Dispersed Composite p-Block Metal Oxide LiInGeO4 with d10−d10 Configuration for Water Decomposition

The ruthenium oxide-loaded composite p-block metal oxide LiInGeO4 with d10-d10 configuration exhibited high photocatalytic activity for the overall splitting of water to produce H2 and O2 under UV irradiation. Changes in the photocatalytic activity with the calcination temperature of LiInGeO4, the amount of RuO2 loaded, and the states of RuO2 indicated that the combination of highly crystallized LiInGeO4 and a high dispersion of RuO2 particles resulted in high photocatalytic activity. Structurally, LiInGeO4 contained heavily distorted InO6 octahedra and GeO4 tetrahedra, generating a dipole moment inside. The high photocatalytic performance of RuO2-loaded LiInGeO4 supports the existing view that the photocatalytic activity correlates with the dipole moment. The DFT calculation showed that the top of the valence band (HOMO) was composed of the O 2p orbital while the bottom of the conduction band (LUMO) was formed by the hybridized In 5s5p + Ge 4s4p + O 2p orbitals. The highly dispersed conduction band, indicative of a high mobility of photoexcited electrons, was responsible for the high photocatalytic performance.

Amyloid beta induces neuronal cell death through ROS-mediated ASK1 activation

Amyloid beta (Abeta) is a main component of senile plaques in Alzheimer's disease and induces neuronal cell death. Reactive oxygen species (ROS), nitric oxide and endoplasmic reticulum (ER) stress have been implicated in Abeta-induced neurotoxicity. We have reported that apoptosis signal-regulating kinase 1 (ASK1) is required for ROS- and ER stress-induced JNK activation and apoptosis. Here we show the involvement of ASK1 in Abeta-induced neuronal cell death. Abeta activated ASK1 mainly through production of ROS but not through ER stress in cultured neuronal cells. Importantly, ASK1-/- neurons were defective in Abeta-induced JNK activation and cell death. These results indicate that ROS-mediated ASK1 activation is a key mechanism for Abeta-induced neurotoxicity, which plays a central role in Alzheimer's disease.

Genetic parameter estimates of meat quality traits in Duroc pigs selected for average daily gain, longissimus muscle area, backfat thickness, and intramuscular fat content

Using a multitrait animal model BLUP, selection was conducted over seven generations for growth rate (ADG), real-time ultrasound LM area (LMA), backfat thickness (BF), and intramuscular fat content (IMF) to develop a new line of purebred Duroc pigs with enhanced meat production and meat quality. This selection experiment examined 543 slaughtered pigs (394 barrows and 153 gilts) from the first to the seventh generation for meat quality traits. Further, electric impedance and collagen content of loin meat were measured from the fourth to sixth generation. The present study was intended to estimate genetic parameters of the correlated traits of tenderness (TEND), meat color (pork color standard: PCS; lightness = L*), drip loss (DL), cooking loss (CL), pH (PH), electric impedance (IMP), and collagen (COL) of the LM, and the genetic trends of these traits. Respective heritability estimates for IMF, TEND, DL, CL, PCS, L*, PH, IMP, and COL were 0.39, 0.45, 0.14, 0.09, 0.18, 0.16, 0.07, 0.22, and 0.23. Genetic correlations of IMF with ADG and BF were low and positive, but low and negative with LMA. Tenderness was correlated negatively with ADG (-0.44) and BF (-0.59), but positively correlated with LMA (0.32). The genetic correlation between LMA and DL was positive and high (0.64). The genetic correlations of TEND with IMF and COL were low (-0.09 and 0.26, respectively), but a moderate genetic correlation (0.43) between COL and IMF was estimated, suggesting related increases of IMF and connective tissue. Genetic correlations among meat quality traits suggested that when IMF increases, the water holding capacity improves. Genetic trends of meat quality traits showed increased IMF and lighter meat color.

Surgically-induced astigmatism following single-site phacotrabeculectomy, phacotrabeculotomy and advanced non-penetrating phacotrabeculectomy

We study surgically-induced astigmatism following three kinds of glaucoma surgeries combined with cataract surgery with 6 months of follow-up. The mean surgically-induced astigmatism at 6 months postoperatively was 1.92 +/- 1.87 diopters in phacotrabeculectomy (n = 45), 0.72 +/- 0.40 diopters in advanced non-penetrating phacotrabeculectomy (n = 40) and 0.76 +/- 0.47 diopters in phacotrabeculotomy (n = 49), which appeared to be stabilized by 3 months. Each group revealed a tendency of "with the wound" induced astigmatism. Phacotrabeculectomy could induce greater surgically-induced astigmatism than advanced non-penetrating phacotrabeculectomy and phacotrabeculotomy.

Genetic correlation between serum insulin-like growth factor-1 concentration and performance and meat quality traits in Duroc pigs1

This study was intended to examine whether serum IGF-I concentration is appropriate for use as a physiological predictor for genetic improvement of meat production and meat quality traits in pigs. Heritabilities and genetic correlations were estimated for these traits. The Duroc breed used in this study was selected for seven generations for average daily BW gain (DG) from 30 to 105 kg of BW, loin-eye muscle area (EM), backfat thickness (BF), and intramuscular fat (IMF) content. Serum IGF-I concentration of boars and gilts at the fourth generation of selection and that of boars, gilts, and barrows from the fifth to seventh generations of selection were measured at 8 wk (IGFI-8W) for 832 animals and again at the time they reached 105 kg of BW (IGFI-105KG) for 834 animals. A multivariate REML procedure was used to estimate genetic parameters with a model incorporating generation of selection, sex, common environmental effect of litter, and individual additive genetic effects. Heritability estimates for IGFI-8W and IGFI-105KG were 0.23 +/- 0.02 and 0.26 +/- 0.03, respectively. The estimates of common environmental effect for IGFI-8W and IGFI-105KG were 0.20 +/- 0.02 and 0.03 +/- 0.01, respectively. Positive genetic correlations were estimated between IGFI-8W and DG (0.26 +/- 0.08), EM (0.22 +/- 0.10), and IMF (0.32 +/- 0.10). Moreover, the positive genetic correlation between IGFI-105KG and EM was 0.42 +/- 0.08. These results indicate that serum IGF-I concentration at an early stage of growth was effective for prediction of IMF, but it was not a reliable physiological predictor of genetic merit of meat production traits.

A genetic variation in the PGC-1 gene could confer insulin resistance and susceptibility to Type II diabetes

AIMS/HYPOTHESIS

Peroxisome proliferator activated receptor gamma coactivator-1 (PGC-1), a transcriptional coactivator of the nuclear receptor PPARgamma, plays a role in adaptive thermogenesis and insulin sensitivity. Plasma fasting insulin has been linked to the chromosomal region where the PGC-1 gene is located. Thus, PGC-1 can be viewed as a functional and positional candidate for the susceptibility gene for Type II (non-insulin-dependent) diabetes mellitus.

METHODS

After screening the PGC-1 gene for single nucleotide polymorphisms (SNPs), we performed an association study using the newly detected SNPs in 537 Type II diabetic patients and 417 non-diabetic subjects.

RESULTS

We found three relatively frequent SNPs in the PGC-1 gene (IVS4-11T > C, Thr394Thr and Gly482Ser). There were significant differences in fasting insulin (Gly/Gly; 37.7 +/- 1.43, Gly/Ser; 40.2 +/- 1.21, Ser/Ser; 44.3 +/- 1.82 pmol/l, p = 0.018) and insulin resistance index (Gly/Gly; 1.48 +/- 0.06, Gly/Ser; 1.56 +/- 0.05, Ser/Ser; 1.75 +/- 0.08, p = 0.027) according to the genotype of the Gly482Ser polymorphism. The Thr394Thr - Gly482Ser haplotype was associated with Type II diabetes (p = 0.00003). CONCLUSION/INTERPRETATION. The results of this study suggested that the PGC-1 gene might be implicated in the pathogenesis of Type II diabetes.

A Japanese case of congenital hyperinsulinism with hyperammonemia due to a mutation in glutamate dehydrogenase (GLUD1) gene

We describe a Japanese case of neonatal hyperinsulinism due to a de novo mutation (Gly446Asp) in glutamate dehydrogenase gene (GLUD1). A boy suffered from hypoglycemic coma with relative hyperinsulinemia on day 1 after birth, and received subtotal pancreatectomy. Examination of the resected pancreas revealed a diffuse increase in endocrine cells, consistent with 'nesidioblastosis'. He is now 15 years old and has exhibited mild but persistent hyperammonemia, which is a very unique feature of the disorder caused by GLUD1 activating mutations. He has also been suffering from seizures and mental retardation. Thus, GLUD1 mutations can be a cause of congenital hyperinsulinism in Japanese.

Mouse integrin alphav promoter is regulated by transcriptional factors Ets and Sp1 in melanoma cells

A 17-bp region between the -31 and -15 bp region of the mouse integrin alphav gene is known to be one of the cis-acting elements for promoter activity. Experimental binding of nuclear proteins to the -31/-15 region reveals that the -27/-16 region mediates the binding. The -27/-16 region, GGCTCCTCCTCC, has a TCCTCC motif, one of the Sp1 binding motifs. An anti-Sp1 IgG and an Sp1-binding oligonucleotide interfered with the binding of nuclear proteins to the -27/-16 oligonucleotide, demonstrating that Sp1 binds to the -27/-16 region. In addition to the -27/-16 region, two other regions, -108/-89 and -64/-44, were found to bind to nuclear proteins within the -108/+1 alphav promoter region. An oligonucleotide containing the Ets-binding consensus sequence of CAGGAAGT interfered with their binding, indicating that both regions have a functional Ets-binding site; which is ACGGAAGT from -106 to -99 bp and ACTTCCTC from -61 to -54 bp, as deduced from the sequence. Mutations in or deletions from any one of three cis-acting elements, the two Ets-binding sites or one Sp1-binding site, remarkably decreased the promoter activity detected in the -108/+1 region. Cotransfection of both Sp1 and Ets-1 cDNAs with the -108/+1 region into B16F10 cells increased the promoter activity 2.9-fold. These results demonstrate that Sp1 and Ets cooperate to activate the -108/+1-alphav promoter region.

The Pro12Ala polymorphism in PPAR gamma2 may confer resistance to type 2 diabetes

Peroxisome proliferator-activated receptor gamma (PPARgamma) has been implicated in adipocyte differentiation. Recently it was reported that heterozygous deficiency of PPARgamma led to the protection from high-fat diet-induced insulin resistance in an animal model. A Pro12Ala polymorphism has been detected in the human PPARgamma2 gene. Since this amino acid substitution may cause a reduction in the transcriptional activity of PPARgamma, this polymorphism may be associated with decreased insulin resistance and decreased risk of type 2 diabetes. To investigate this hypothesis, we performed a case-control study of the Pro12Ala PPARgamma2 polymorphism in Japanese diabetic and non-diabetic subjects. The frequency of Ala12 was significantly lower in the diabetic group. In an overweight or obese group, subjects with Ala12 were more insulin sensitive than those without. These results suggest that the PPARgamma is a thrifty gene and that the Pro12Ala PPARgamma2 polymorphism protects against type 2 diabetes in the Japanese.

Synthesis of 8-epi-prostaglandin F2alpha by human endothelial cells: role of prostaglandin H2 synthase

The experiments described in this paper were designed to determine the mechanism underlying the increase in 8-isoprostaglandin F(2alpha) (8-epi-PGF(2alpha)) production by cultured human endothelial cells during reoxygenation following hypoxia. Human umbilical artery endothelial cells were grown on microcarrier beads and exposed to sequential periods of normoxia, hypoxia, and reoxygenation. The amount of 8-epi-PGF(2alpha) in the medium was determined by ELISA. The production of 8-epi-PGF(2alpha) decreased by greater than 90% during hypoxia. Upon reoxygenation 8-epi-PGF(2alpha) production increased linearly for 90 min reaching nearly 3 times normoxic levels. When added to the medium during reoxygenation, neither superoxide dismutase nor Tiron, a cell-permeable superoxide scavenger, inhibited 8-epi-PGF(2alpha) production. However, 8-epi-PGF(2alpha) production was inhibited by catalase. The production of 8-epi-PGF(2alpha) was also inhibited by indomethacin and aspirin. Exogenous hydrogen peroxide stimulated 8-epi-PGF(2alpha) production by normoxic cells, and aspirin inhibited the hydrogen peroxide-mediated increase in 8-epi-PGF(2alpha) production. These results indicate that the reactive oxygen species responsible for 8-epi-PGF(2alpha) synthesis during reoxygenation is hydrogen peroxide and that in endothelial cells 8-epi-PGF(2alpha) synthesis is mediated by prostaglandin H(2) synthase (PGHS). To verify the role of PGHS in 8-epi-PGF(2alpha) synthesis, human PGHS-1 was expressed in COS-7 cells, a PGHS negative cell line that does not synthesize 8-epi-PGF(2alpha). In the presence of exogenous arachidonic acid the COS-7 cells expressing human PGHS-1 produced substantial amounts of PGE(2) and 8-epi-PGF(2alpha). These data indicate that human PGHS-1 can support the synthesis of 8-epi-PGF(2alpha) and that 8-epi-PGF(2alpha) synthesis by cultured human endothelial cells during reoxygenation is dependent on the activity of PGHS-1.

Molecular and histological evaluation of pancreata from patients with a mitochondrial gene mutation associated with impaired insulin secretion

A mutation in mitochondrial DNA, which was originally identified in patients with mitochondrial myopathy, encephalopathy, lactic acidosis, and stroke-like episodes (MELAS), can be associated with a subtype of diabetes mellitus. To determine the molecular and histological basis of impaired insulin secretion in the subjects with this mutation, we studied autopsy pancreata specimens from eight subjects diagnosed as having MELAS. The 3243 bp mutation was identified in seven out of eight pancreata examined. Immunohistochemical studies demonstrated a reduction in total islet mass, and in the numbers of both B and A cells. No evidence of insulitis or apoptosis was found. These data suggested that the 3243 bp mutation may cause the reduction of islet cells, mainly through mechanisms other than autoimmune destruction.

Proposed standard for human blood vitamin B1 value using HPLC. The Committee for Vitamin Laboratory Standards, Japan

Standard reference ranges for all laboratory test values are mandatory. This study was designed to establish a reference range for blood vitamin B1 levels, since the normal range has not been determined in the Japanese population. We founded the Japan Committee for Vitamin Laboratory Standards, which was incorporated with the Vitamin Society of Japan and the Japanese Society of Nutrition and Food Science. We standardized whole blood vitamin B1 levels using three HPLC techniques (post-column reverse-phase HPLC, pre-column reverse-phase HPLC, and precolumn GP-HPLC). The reference range was obtained in 54 volunteers administered a 1,800 kcal diet with 2 mg of vitamin B1 (1.74 mg measured) daily to avoid marginal vitamin B1 deficiency in the population. The range for each assay was 26-47, 28-51, and 28-56 ng/ml, respectively. Our data suggest that 26-28 ng/ml is the lower limit of normal for whole blood vitamin B1, but further studies in a larger population are needed in order to obtain more definitive results.

Effect of the Pro12Ala variant of the human peroxisome proliferator-activated receptor gamma 2 gene on adiposity, fat distribution, and insulin sensitivity in Japanese men

To examine the role of the Pro12Ala variant of the human PPARgamma2 gene on adiposity and insulin resistance, we studied the effect of the variant on fat distribution assessed by CT scan, plasma glucose, and insulin levels during a 75g oral glucose load in 215 non-diabetic Japanese men. The allele frequency of the variant was 0. 03 in this population. There were no differences in body mass index (BMI), subcutaneous fat area (S), visceral fat area (V), V/S ratio, fasting plasma insulin levels, or insulin resistance index in homeostatic model assessment between 203 subjects who were homozygous for the wild-type Pro12 allele and 12 subjects with the variant Ala12 allele (11 heterozygotes and one homozygote). These data suggest that the Pro12Ala variant is not a major contributor to adiposity, fat distribution, or insulin resistance in Japanese men.

Two aberrant splicings caused by mutations in the insulin receptor gene in cultured lymphocytes from a patient with Rabson-Mendenhall's syndrome

Rabson-Mendenhall's syndrome is one of the most severe forms of insulin resistance syndrome. We analyzed an English patient described elsewhere and found novel mutations in both alleles of the insulin receptor gene. One is a substitution of G for A at the 3' splice acceptor site of intron 4, and the other is an eight-base pair deletion in exon 12. Both decrease mRNA expression in a cis-dominant manner, and are predicted to produce severely truncated proteins. Surprisingly, nearly normal insulin receptor levels were expressed in the patient's lymphocytes, although the level of expression assessed by immunoblot was approximately 10% of the control cells. Insulin binding affinity was markedly reduced, but insulin-dependent tyrosine kinase activity was present. Analyzing the insulin receptor mRNA of the patient's lymphocytes by reverse transcription PCR, we discovered aberrant splicing caused by activation of a cryptic splice site in exon 5, resulting in a four-amino acid deletion and one amino acid substitution, but restoring an open reading frame. Skipped exon 5, another aberrant splicing, was found in both the patient and the mother who had the heterozygotic mutation, whereas activation of the cryptic splice site occurred almost exclusively in the patient. Transfectional analysis in COS cells revealed that the mutant receptor produced by cryptic site activation has the same characteristics as those expressed in patient's lymphocytes. We speculate that this mutant receptor may be involved in the relatively long survival of the patient by rescuing otherwise more severe phenotypes resulting from the complete lack of functional insulin receptors.

Exchangeability of the b subunit of the Cl(-)-translocating ATPase of Acetabularia acetabulum with the beta subunit of E. coli F1-ATPase: construction of the chimeric beta subunits and complementation studies

The gene encoding the b subunit of the Cl(-)-translocating ATPase (aclB) was isolated from total RNA and poly(A)+ RNA of Acetabularia acetabulum and sequenced (total nucleotides of 3038 bp and an open reading frame with 478 amino acids). The deduced amino acid sequence showed high similarity to the beta subunit of the F type ATPases, but was different in the N-terminal 120 amino acids. The role of the N-terminal region was investigated using an F -ATPase beta-less mutant of E. coli, JP17. The JP17 strain expressing the aclB could not grow under conditions permitting oxidative phosphorylation, although ACLB was detected in the membrane fraction. The beta subunit was divided into three portions: amino acid position from 1 to 95 (portion A), 96 to 161 (portion B) and 162 to the C-terminus (portion C). The corresponding regions of ACLB were designated as portions A' (from 1 to 106), B' (from 107 to 172) and C' (from 173 to 478). Chimeric proteins with combinations of A-B'-C', A-B-C' and A'-B-C restored the function as the beta subunit in E. coli F0F1-complex, but those with combinations of A'-B'-C and A-B'-C had no function as the beta subunit. These findings suggested that portion B plays an important role in the assembly and function of the beta subunit in the F0F1-complex, while portion B' of ACLB exhibited inhibitory effects on assembly and function. In addition, portion A was also important for interaction of the beta subunit with the alpha subunit in E. coli F0F1-complex. These findings also suggested that the b subunit of the Cl(-)-translocating ATPase of A. acetabulum has a different function in the Cl(-)-translocating ATPase complex, although the primary structure resembled to the beta subunit of the F1-ATPase.

[The long-term cystic bleb appearance and safety after trabeculectomy with mitomycin C]

The clinical appearance of cystic blebs and the incidence of bleb infection were retrospectively evaluated in 215 trabeculectomies with mitomycin C. The incidence of cystic bleb formation in trabeculectomy was 79% (169/215). The cumulative incidence of the cystic bleb survival when using the Kaplan-Meier method was 73% in the 50th month after surgery. The incidence of large cystic bleb survival was better than that of small and localized cystic blebs. There was statistically significant difference. The incidence of cystic bleb survival without Seidel phenomenon and bleb infection was 96% in the first year after surgery and 91% in the third year. Bleb infections occurred in two of 169 eyes (1.2%). Bleb infection was successfully treated and there were no cases of endophthalmitis. The large cystic blebs had a higher incidence of bleb infection than the small ones. In one of 25 eyes treated with antibiotic eye drops after surgery, the Seidel test was positive and bleb infection occurred. The Seidel test was positive in 5 of 96 eyes in which antibiotic eye drops were not used and bleb infection occurred in one of these 5 eyes.

Diabetes mellitus associated with the 3243 mitochondrial tRNA(Leu)(UUR) mutation: insulin secretion and sensitivity

To investigate the pathophysiology of diabetes mellitus associated with the 3243 mitochondrial tRNA(Leu)(UUR) mutation (DM-Mt3243), insulin secretion and sensitivity were studied using the 75-g oral glucose tolerance test (oGTT), 1-mg intravenous glucagon test, and euglycemic glucose clamp test. Twelve DM-Mt3243 patients were investigated (seven men and five women). Their ages ranged from 36 to 74 years, and the onset of diabetes occurred at 44.5 +/- 9.5 years (mean +/- SD). In the glucose tolerance test, nine patients (75.0%) showed lower C-peptide reactivity (CPR) than normal at 30 minutes, suggesting blunted insulin secretion. Three patients showed an impaired glucose tolerance (IGT) pattern, although they had absolute hyperglycemia at the onset of diabetes. In the glucagon test, 10 patients (76.3%) had CPR within the normal range at 6 minutes, indicating an adequate response. In the glucose clamp test, the M value was 8.70 +/- 2.35 mg/kg/min and was within normal limits in all patients. The glucose metabolized (M value) was negatively correlated with 24-hour urinary C-peptide excretion (r = .696, P < .05). Thus, plasma CPR to glucose loading was blunted in many DM-Mt3243 patients, but CPR to glucagon was relatively well preserved. This difference in the intrinsic insulin response to the two stimuli may be characteristic of DM-Mt3243. Although M values were normal in all subjects, the correlation with 24-hour urinary C-peptide excretion suggests a relationship between insulin sensitivity and insulin secretion. These two mechanisms may cooperate to maintain homeostasis in this disease. Since three patients did not progress with aging, this mutation may not always cause gradual beta-cell destruction.

Four mutant alleles of the insulin receptor gene associated with genetic syndromes of extreme insulin resistance

We identified four novel mutant alleles of the insulin receptor gene in three patients with genetic syndromes associated with insulin resistance. Two mutant alleles of the insulin receptor gene were identified in a patient with the Rabson-Mendenhall syndrome who was a compound heterozygote for a mutation at the 3'-splice acceptor site of intron 4 (AG-->GG), the first mutation causing an aberrant splicing at this locus, and a deletion of eight base pairs in exon 12. The second patient with leprechaunism was also a compound heterozygote for a deletion of one base pair in exon 19 and a mutation, Thr910-->Met, which causes impaired receptor processing. Interestingly, the third patient with type A syndrome was a simple heterozygote for the identical one base pair deletion. The fact that the same one base pair deletion links to type A in a simple heterozygote and to leprechaunism in a compound heterozygote appears consistent with the hypothesis that the severity of mutations will determine the phenotype.

[Blood amino acid levels in sarin poisoning patients]

Since plasma is generally employed for amino acid analysis, we compared amino acid levels in plasma with those in serum for healthy individuals and examined the influence of separation and storage conditions on the stability of the samples. Then, we determined the amino acid levels of frozen serum samples obtained from sarin poisoned patients. A. Comparison of Amino Acid Levels in Plasma and Those in Serum Blood was collected from 5 healthy individuals. Then, heparinated plasma and serum were separated by centrifugation immediately after blood collection. Serum was also separated by centrifugation after standing whole blood at room temperature for 1 hour. Frozen plasma and serum were store at -40 degrees C for 5 months. All were subjected to analysis in an amino acid analyzer. It was found that the cystine (Cys) and 3-methyl-histidine (3-M-His) levels in serum and plasma were affected when stored in a frozen state, that the aspartate (Asp) level was changed according to the method of collecting serum, and that the taurine (Tau) and ornithine (Orn) levels were affected by standing blood. B. Analysis of Blood Taken from Sarin Poisoned Patients Twelve sarin poisoned patients were selected as subjects, and serum cholinesterase (Ch-E) and serum albumin (Alb) levels were determined. Amino acid analysis was conducted using an amino acid analyzer. Serum samples which had been obtained from the 6 patients and frozen and stored at -40 degrees C from 5 months were used for amino acid analysis. As a result, the serum Ch-E level decreased and the Alb level tended to rise. Since the Ch-E/Alb ratio was reduced in the sarin poisoned patients, it is considered useful for discrimination from liver cirrhosis in which both Ch-E and Alb levels decreased. Amino acid levels in the serum obtained from the sarin poisoned patients were compared with those of healthy individuals, both of which had been stored under the same conditions. There were significant differences in Asp, glutamate (Glu), phenylalanine (Phe), 3-M-His, glutamine (Gln), and Cys levels. The Glu, Phe, and Gln levels were not affected by storage of serum in a frozen state, while the Glu and Phe levels were elevated and the Gln level was reduced. Although Cys exhibited lower values in frozen serum samples, the Cys level was elevated with a rise in the serum Ch-E levels. Therefore, we deduced that Cys metabolism disorders also occur in sarin poisoning. As stated above, the Glu and Phe levels were elevated and the Gln and Cys levels were reduced, suggesting the presence of abnormal amino acid metabolism, in patients with sarin-poisoning.

A homozygous kinase-defective mutation in the insulin receptor gene in a patient with leprechaunism

We report a homozygous missense mutation at position 1092 (substitution of glutamine for arginine) in the tyrosine kinase domain of the insulin receptor in a patient with leprechaunism associated with severe insulin resistance and intrauterine growth retardation. Site-directed mutagenesis as well as analyses of the patient's lymphocytes revealed that this mutation causes a marked decrease in tyrosine kinase activity of the insulin receptor without any defect in insulin binding, which causes severe defects in insulin-stimulated glucose transport, glycogen synthesis and DNA synthesis. Thus, this is the first homozygous mutation resulting in a selective-kinase defect of the insulin receptor. Interestingly, the parents who are cousins and are heterozygous for the mutation have type A insulin resistance syndrome. This correlation between genotype and phenotype in a single pedigree suggests that the severity of the mutation will determine the phenotype. Based upon this assumption, we have been successful in prenatal diagnosis of the fifth child. Furthermore, we have demonstrated the effectiveness of clinical administration of insulin-like growth factor-I (IGF-I) in this patient and in vitro analysis of the patient's skin fibroblasts, suggesting that IGF-I can compensate for insulin action via the IGF-I receptor in a patient almost lacking functional insulin receptors.

The primary structure of the Cl(-)-translocating ATPase, b subunit of Acetabularia acetabulum, which belongs to the F-type ATPase family

The genes possibly encoding the b subunit (50 kDa) of the Cl(-)-translocating ATPase of Acetabularia acetabulum were cloned from total RNA and from poly(A)+ RNA and sequenced. The deduced amino acid sequence of the open reading frame consisted of 478 amino acids and showed high similarity to the beta subunit of chloroplast F1-ATPase. Gene fragments encoding the putative beta subunit of chloroplast F1- (273 bp) and mitochondrial F1-ATPases (332 bp) were also cloned from A. acetabulum and sequenced, respectively. The deduced amino acid sequence of the chloroplast F1-ATPase showed 92.5% identity to be primary structure of the b subunit of the Cl(-)-translocating ATPase, while the nucleotide sequences were 79.9% identical. The deduced amino acid sequence of the latter was 77.3% identical to that of the b subunit of the Cl(-)-translocating ATPase and the nucleotide sequences were 67.5% identical. By Northern analysis, these three beta-like genes were demonstrated to be transcribed with different sizes of RNA species. A putative chloroplast F1-beta fragment also hybridized with chloroplast DNA isolated from the organism.