Frequent somatic mutations in epigenetic regulators in newly diagnosed chronic myeloid leukemia.

Although tyrosine kinase inhibitors (TKIs) have significantly improved the prognosis of chronic myeloid leukemia (CML), the ability of TKIs to eradicate CML remains uncertain and patients must continue TKI therapy for indefinite periods. In this study, we performed whole-exome sequencing to identify somatic mutations in 24 patients with newly diagnosed chronic phase CML who were registered in the JALSG CML212 study. We identified 191 somatic mutations other than the BCR-ABL1 fusion gene (median 8, range 1-17). Age, hemoglobin concentration and white blood cell counts were correlated with the number of mutations. Patients with mutations ⩾6 showed higher rate of achieving major molecular response than those<6 (P=0.0381). Mutations in epigenetic regulator, ASXL1, TET2, TET3, KDM1A and MSH6 were found in 25% of patients. TET2 or TET3, AKT1 and RUNX1 were mutated in one patient each. ASXL1 was mutated within exon 12 in three cases. Mutated genes were significantly enriched with cell signaling and cell division pathways. Furthermore, DNA copy number analysis showed that 2 of 24 patients had uniparental disomy of chromosome 1p or 3q, which disappeared major molecular response was achieved. These mutations may play significant roles in CML pathogenesis in addition to the strong driver mutation BCR-ABL1.

Active and passive exposure to tobacco smoke in relation to insulin sensitivity and pancreatic ß-cell function in Japanese subjects.

AIM: Several studies have suggested that cigarette-smoking affects insulin sensitivity in Western populations. The present study evaluated glucose tolerance, pancreatic ß-cell function and insulin sensitivity in relation to active and passive smoking among the Japanese. METHODS: A total of 411 men and 586 women were recruited into a community-based cross-sectional study in Gifu, Japan. Diabetes, impaired glucose tolerance (IGT) and impaired fasting glucose (IFG) were screened for by a 75g oral glucose tolerance test. HOMA and insulinogenic (ΔI0-30/ΔG0-30) indexes were used to estimate insulin secretion and sensitivity. To assess the possible association of self-reported smoking status and parameters of glucose metabolism, logistic regression was applied after adjusting for potential confounders. RESULTS: Currently smoking women were more likely to have diabetes, IGT or IFG compared with never-smoking women (OR: 2.26, 95% CI: 1.05-4.84). Heavy-smoking men (≥25 cigarettes/day) were likely to be in the lowest tertile group of ΔI0-30/ΔG0-30 compared with never-smoking men (OR: 2.64, 95% CI: 1.05-6.68, Ptrend=0.04). The number of cigarettes/day was borderline significantly associated with diabetes in men. Also with borderline significance, never-smoking women with smoking husbands were more likely to have diabetes, IGT or IFG (OR: 1.62, 95% CI: 1.00-2.62) and significantly more likely to have lower HOMA-ß (OR: 2.17, 95% CI: 1.36-3.48) than those without smoking husbands. CONCLUSION: The greater the number of cigarettes smoked per day appears to be associated with diabetes among men whereas, among women, both active and passive smoking appear to be associated with diabetic states, including IGT and IFG. An association between smoking status and insulin secretion is also suggested, whereas no significant association was observed with HOMA-IR in this Japanese subjects, suggesting that the influence of smoking on glucose metabolism may differ among races.

Screening of diabetes of youth for hepatocyte nuclear factor 1 mutations: clinical phenotype of HNF1ß-related maturity-onset diabetes of the young and HNF1α-related maturity-onset diabetes of the young in Japanese.

AIM: To compare the prevalence and clinical features of HNF1ß-related MODY and HNF1α-related MODY in Japanese. METHODS: We enrolled 230 Japanese patients with suspected MODY and examined them for HNF1α and HNF1ß mutations. We characterized the clinical features of HNF1ß-related MODY (HNF1ß-MODY) and HNF1α-related MODY (HNF1α-MODY). RESULTS: Six patients had HNF1ß mutations, four of which were large gene deletions and 24 patients had HNF1α mutations, which included one gene deletion. The mean fasting plasma glucose level at onset of HNF1ß-MODY was considerably higher and the age of onset of HNF1ß-MODY was considerably older than they were for HNF1α-MODY, while the mean BMI and C-peptide index at onset were similar. Three patients with HNF1ß-MODY were found to have dorsal pancreatic agenesis and four of them had whole-gene deletion. Five of the patients with HNF1ß-MODY had insulin secretion defects and were treated with insulin, and four of these did not have a parent with overt diabetes. CONCLUSION: HNF1ß-MODY may present as ß-cell dysfunction in Japanese rather than as hyperinsulinaemia, which it does among European/American. This dysfunction might result from an intrinsically lower capacity for insulin secretion in Japanese. HNF1ß-MODY has an older age of onset than HNF1α-MODY, which may suggest lower penetrance of the disease. In addition, HNF1ß-MODY has a broad spectrum of clinical manifestations, some of which are detectable by imaging. This may be helpful in some cases for selecting HNF1ß-MODY candidates for genetic testing.

The effects of doxapram on medullary respiratory neurones in brainstem-spinal cord preparations from newborn rats.

Doxapram is the only dedicated respiratory stimulant used to aid recovery of breathing after major surgery. Doxapram acts on peripheral chemoreceptors and although the central action of doxapram has been suggested, its detailed neuronal mechanism is unknown. We assessed doxapram-induced changes in spontaneous cervical nerve (C4) inspiratory activity and the firing of action potentials in pre-inspiratory and inspiratory neurones in the medulla. Experiments were performed in neonatal rat brainstem-spinal cord preparations, which can produce respiratory rhythm for several hours under in vitro conditions. Doxapram application (for 15 min) increased the frequency and amplitude of C4 activity dose-dependently. Doxapram induced changes in the electrophysiological properties of pre-inspiratory and inspiratory neurones. Our results suggest that respiratory activity enhancement was likely to be induced via effects on the potassium channels of pre-inspiratory and inspiratory neurones and indicate the central actions of doxapram.

Electronic excited states of a strongly correlated organic radical 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA) adsorbed on a Si(001) surface.

Electronic excited states of a strongly correlated organic radical, 1,3,5-trithia-2,4,6-triazapentalenyl (TTTA), adsorbed on a Si(001) surface were investigated by means of two-photon photoemission spectroscopy (2PPE) to elucidate the functional organic thin-film formation on a typical semiconductor substrate. The spectra were interpreted with the aid of density functional theoretical calculations. The unpaired electron of TTTA forms a covalent bond with the dangling bond of the Si-dimer initially, and there are resonant states of TTTA to Si near the surface. The molecules adsorbed at room temperature form dimers having diamagnetic properties at thicknesses of a few monolayers, while the paramagnetic phase appears at multilayer thickness. From the change in the work function, the orientation of the adsorbed TTTA molecules was determined to change depending on the thickness of the adsorbed layer.

Descending aortic blood flow during aortic cross-clamp indicates postoperative splanchnic perfusion and gastrointestinal function in patients undergoing aortic reconstruction.

BACKGROUND: The purpose of this observational study was to investigate the relationship between splanchnic and renal blood flow during infrarenal aortic cross-clamp (XC) and postoperative gastrointestinal perfusion and function. METHODS: Descending aortic blood flow (DABF) was continuously monitored with an oesophageal Doppler monitor (Cardio-Q, Deltex Ltd, Chichester, UK) in 31 patients undergoing elective abdominal aortic aneurysm repair. Cardiac output (CO) was determined by indocyanine green dilution before, during, and after XC. Perioperative gastrointestinal perfusion was assessed by gastric intramucosal pH (pHi, Tonocap, GE Healthcare, Helsinki, Finland). Postoperative gastrointestinal recovery was assessed by the number of postoperative days until the patient successfully resumed solid food intake. The relationship between the mean DABF during XC and gastric pHi after XC release and postoperative gastrointestinal recovery was analysed with Spearman's correlation coefficient. RESULTS: accounted for ∼ 55% of CO during XC and significantly decreased during XC, despite arterial pressure remaining within an optimal range. There were two distinct relationships between DABF during XC and gastric pHi after XC release. Gastric pHi steeply and linearly declined when indexed DABF was below 0.82 litre min(-1) m(-2). Above this critical value, there was no linear relationship between them. The duration of postoperative gastrointestinal dysfunction was inversely correlated with the mean DABF during XC. The best cut-off value of the mean indexed DABF during XC to prevent prolonged gastrointestinal dysfunction was 1.2 litre min(-1) m(-2). CONCLUSIONS: Decreased DABF during XC associates splanchnic hypoperfusion after XC release and delayed recovery of gastrointestinal function.

Ferroelectric soft mode in a SrTiO3 thin film impulsively driven to the anharmonic regime using intense picosecond terahertz pulses.

The ferroelectric soft mode in a SrTiO(3) thin film was impulsively driven to a large amplitude using intense picosecond terahertz pulses. As the terahertz electric field increased, the soft-mode absorption peak exhibited blueshifting and spectral narrowing. A classical anharmonic oscillator model suggests that the induced displacement is comparable to that of the ferroelectric phase transition. The spectral narrowing indicates that the displacement exceeds that induced by any inhomogeneities in the film, demonstrating that the method can be used to explore intrinsic quartic anharmonicity.

Ultrafast lasing due to electron-hole plasma in ZnO nano-multipods.

Dynamics of stimulated emission and ultrafast lasing in ZnO nano-multipods has been investigated with a femtosecond optical Kerr shutter technique. Under band-to-band excitation with high density, stimulated emission is observed around 395-400 nm with a mode-like structure. The stimulated emission emerges with an onset time of ∼2 ps and then the intensity gradually decreases with time having a blue-shift and a spectral narrowing. The characteristics of the blue-shift and spectral narrowing suggest that not only recovery of bandgap renormalization but also conversion from an electron-hole plasma (EHP) state to high density excitonic state takes place as the carrier density decreases due to recombination of electrons with holes. The mode-like structure observed strongly indicates that a high quality resonant cavity is formed between the two facets toward the leg length direction of individual nano-multipod. These results show that the ultrafast lasing observed around 395-400 nm in ZnO nano-multipods comes from population inversion in the EHP regime. We also found that the initial carrier distribution of the EHP regime in nano-multipods is much wider than that in ZnO thin films, implying that the carrier diffusion might be suppressed by their nano-size structure.

Effects of spinal anesthesia on the electroencephalogram in the elderly.

Elderly patients frequently fall asleep during spinal anesthesia without sedatives. We investigated effects of spinal anesthesia on electroencephalogram (EEG) in elderly patients. Elderly patients were randomly assigned. Patients in Group C (n = 8) received an epidural catheter with no anesthetics as control; patients in Group S (n = 8) received spinal anesthesia. Subsequently, processed EEG data were monitored for 5 minutes. Spinal anesthesia induced significant decreases in 90% spectral edge frequency (SEF90), whereas the control group had no change in SEF90. It was concluded that spinal anesthesia induces decreased SEF90, indicating suppressed cortical activity in early phases of sensory blockade in elderly patients.

Fabrication and excitation-power-density-dependent micro-photoluminescence of hexagonal nanopillars with a single InGaAs/GaAs quantum well.

Hexagonal nanopillars with a single InGaAs/GaAs quantum well (QW) were fabricated on a GaAs (111)B substrate by selective-area metal-organic vapor phase epitaxy. The standard deviations in diameter and height of the nanopillars are about 2% and 5%, respectively. Zincblende structure and rotation twins were identified in both the GaAs and the InGaAs layers by electron diffraction. The excitation-power-density-dependent micro-photoluminescence (µ-PL) of the nanopillars was measured at 4.2, 50, 100 and 150 K. It was shown that, with increasing excitation power density, the µ-PL peak's positions shift to a higher energy, and their intensity and width increase, which were rationalized using a model that includes the effects of piezoelectricity, photon-screening and band-filling. It was also revealed that the rotation twins significantly reduce the diffusion length of the carriers in the nanopillars, compared to that in the regular semiconductors.

p21 provides stage specific DNA damage control to preimplantation embryos.

The early stage embryogenesis of higher eukaryotes lacks some of the damage response pathways such as G1/S checkpoint, G2/M checkpoint and apoptosis. We examined here the damage response of preimplantation stage embryos after fertilization with 6 Gy irradiated sperm. Sperm-irradiated embryos developed normally for the first 2.5 days, but started to exhibit a developmental delay at day 3.5. p21 was activated in the delayed embryos, which carried numerous micronuclei owing to delayed chromosome instability. Apoptosis was observed predominantly in the inner cell mass of the day 4.0 embryos. Sperm-irradiated p21-/- embryos lacked the delay, but chromosome instability and apoptosis were more pronounced than the corresponding p21 wild-type embryos. We conclude from the result that damage responses come in a stage-specific manner during preimplantation stage development; p53-dependent S checkpoint at the zygote stage, p21-mediated cell cycle arrest at the morula/blastocyst stages and apoptosis after the blastocyst stage in the inner cell mass.

Pretreatment with magnesium sulphate is associated with less succinylcholine-induced fasciculation and subsequent tracheal intubation-induced hemodynamic changes than precurarization with vecuronium during rapid sequence induction.

Although it has side effects, succinylcholine is still widely used in rapid sequence induction. The aim of the present study is to evaluate the effects of pretreat ment with magnesium and precurarization of vecuroni um on succinylcholine-induced fasciculation and subse quent tracheal intubation-induced hemodynamic changes during rapid sequence induction. Fifty-five patients were allocated to three groups by a blinded randomization: Group M received saline 100 ml with magnesium 40 mg x kg(-1) for 5 min at 6.5 min before induction and sub sequently administered saline 1-2 ml at 1.5 min before induction; Group V received saline 100 ml for 5 min at 6.5 min before induction and subsequently administered vecuronium 0.02 mg x kg(-1) at 1.5 min before induction; Group C received saline 100 ml for 5 min at 6.5 min before induction and then saline 1-2 ml at 1.5 min before induction. Fasciculation scores and mean percent changes of heart rate, systolic blood pressure and rate pressure product between baseline and after induction were significantly lower in group M than those in group C and group V. Pretreatment with magnesium is more effective to limit succinylcholine-induced fasciculation and subsequent tracheal intubation-induced hemody namic changes in rapid sequence induction compared with vecuronium pretreatment, although magnesium does not prevent the elevation of serum potassium con centration after induction.

New strategy for comprehensive analysis of gene functions in embryonic stem cells.

At present, the limitation of Phenotype-based genetic screening in embryonic stem cells (ESCs) is the diploid nature of the genome. Since it is known that cells deficient in the Bloom's syndrome gene (Blm) show an increased rate of homologous recombination, we have developed a new system to conditionally regulate the Blm allele for introduction of bi-allelic mutations across the genome. Transient deficiency of Blm induces homologous recombination not only between sister chromatids but also between homologous chromosomes, resulting in a high rate of loss of heterozygosity (LOH). Introduction of genome-wide mutations in ESCs can be achieved by retroviral vector. In combination, using genome-wide mutagenesis and transient loss of Blm expression, we have generated ES libraries with bi-allelic mutations. These results show that this new system is very efficient for identifying gene functions in ESCs.

Gene expression profile in rat pancreatic islet and RINm5F cells.

To clarify tissue-specificity of pancreatic beta cells, comparison of mRNA expression in various conditions of the tissue of multiple organisms is important. Although the developed methodologies for mRNA monitoring such as microarray, rely on the growth of dbEST (database of expressed sequence tag), a large number of unknown genes in the genome, especially in the rat, have not been shown to be expressed. In this study, we have established the first database of ESTs from rat pancreatic islet and RINm5F cells. Two cDNA libraries were constructed using mRNAs from rat pancreatic islet and RINm5F cells to cover a wider spectrum of expressed genes. Over 40,000 clones were randomly selected from the two libraries and partially sequenced. The sequences obtained were subjected to BLAST database analyses. This large-scale sequencing generated 40,710 3'-ESTs. Clustering analysis and homology search of nucleotide and peptide databases using both 3'- and 5'-ESTs revealed 10,406 non-redundant transcripts representing 4078 known genes or homologs and 6328 unknown genes. To confirm actual expression, the unknown sequences were further subjected to dbEST search, resulting in the identification of 5432 significant matches to those from other sources. Interestingly, of the remaining sequences showing no match, 779 were found to be encoded by exon-intron organization in the corresponding genomic sequences, suggesting that these are newly found as actually expressed in this study. Since many genes are up- or down-regulated in differing conditions, applications of the expression profile should facilitate identification of the genes involved in cell-specific functions in normal and disease states.

Methylation of the oestrogen receptor gene in non-neoplastic epithelium as a marker of colorectal neoplasia risk in longstanding and extensive ulcerative colitis.

BACKGROUND: Surveillance colonoscopy is widely recommended in patients with longstanding and extensive ulcerative colitis (UC) in order to detect colorectal neoplasia at an early stage. However, it still remains questionable whether surveillance colonoscopy effectively enables early detection of UC associated neoplasia. There is a great need for sensitive markers to identify individuals at increased risk of neoplasia. The oestrogen receptor (OR) gene shows age related methylation in the colorectal epithelium and is methylated frequently in sporadic colorectal neoplasia, suggesting that OR methylation may predispose to colorectal neoplasia. AIM: To clarify whether analysis of methylation of the OR gene in non-neoplastic epithelium can contribute to prediction of increased neoplasia risk in UC patients. MATERIALS AND METHODS: A total of 165 non-neoplastic colorectal epithelia from 30 patients with longstanding and extensive UC, including 13 UC patients with neoplasia and 17 patients without, were evaluated. Methylation specific polymerase chain reaction was performed to determine the methylation status of the OR gene. RESULTS: Methylation of the OR gene was detected in 54 of 70 (77.1%) non-neoplastic colorectal epithelia in UC with neoplasia but in only 23 of 95 (24.2%) without neoplasia. Methylation of the OR gene was significantly more frequent in non-neoplastic epithelium from UC with neoplasia than in chronic colitic epithelium from UC without neoplasia. Furthermore, in UC with neoplasia, the OR gene was extensively methylated in non-neoplastic epithelia throughout the colorectum compared with those in UC without neoplasia. CONCLUSION: These results suggest that analysis of OR gene methylation may have potential as a useful marker for identifying individuals at increased risk of neoplasia among those with longstanding and extensive UC.