Discovery of New Isotope

The new isotope ^{241}U was synthesized and systematic atomic mass measurements of nineteen neutron-rich Pa-Pu isotopes were performed in the multinucleon transfer reactions of the ^{238}U+^{198}Pt system at the KISS facility. The present experimental results demonstrate the crucial role of the multinucleon transfer reactions for accessing unexplored neutron-rich actinide isotopes toward the N=152 shell gap in this region of nuclides.

First Application of Mass Measurements with the Rare-RI Ring Reveals the Solar r-Process Abundance Trend at A=122 and A=123.

The Rare-RI Ring (R3) is a recently commissioned cyclotronlike storage ring mass spectrometer dedicated to mass measurements of exotic nuclei far from stability at Radioactive Isotope Beam Factory (RIBF) in RIKEN. The first application of mass measurement using the R3 mass spectrometer at RIBF is reported. Rare isotopes produced at RIBF-^{127}Sn, ^{126}In, ^{125}Cd, ^{124}Ag, ^{123}Pd-were injected in R3. Masses of ^{126}In, ^{125}Cd, and ^{123}Pd were measured whereby the mass uncertainty of ^{123}Pd was improved. This is the first reported measurement with a new storage ring mass spectrometry technique realized at a heavy-ion cyclotron and employing individual injection of the preidentified rare nuclei. The latter is essential for the future mass measurements of the rarest isotopes produced at RIBF. The impact of the new ^{123}Pd result on the solar r-process abundances in a neutron star merger event is investigated by performing reaction network calculations of 20 trajectories with varying electron fraction Y_{e}. It is found that the neutron capture cross section on ^{123}Pd increases by a factor of 2.2 and ß-delayed neutron emission probability, P_{1 n}, of ^{123}Rh increases by 14%. The neutron capture cross section on ^{122}Pd decreases by a factor of 2.6 leading to pileup of material at A=122, thus reproducing the trend of the solar r-process abundances. The trend of the two-neutron separation energies (S_{2n}) was investigated for the Pd isotopic chain. The new mass measurement with improved uncertainty excludes large changes of the S_{2n} value at N=77. Such large increase of the S_{2n} values before N=82 was proposed as an alternative to the quenching of the N=82 shell gap to reproduce r-process abundances in the mass region of A=112-124.

Cholesterol 25-hydroxylase is a metabolic switch to constrain T cell-mediated inflammation in the skin.

Interleukin-27 (IL-27) is an immunoregulatory cytokine whose essential function is to limit immune responses. We found that the gene encoding cholesterol 25-hydroxylase (Ch25h) was induced in CD4+ T cells by IL-27, enhanced by transforming growth factor­ß (TGF-ß), and antagonized by T-bet. Ch25h catalyzes cholesterol to generate 25-hydroxycholesterol (25OHC), which was subsequently released to the cellular milieu, functioning as a modulator of T cell response. Extracellular 25OHC suppressed cholesterol biosynthesis in T cells, inhibited cell growth, and induced nutrient deprivation cell death without releasing high-mobility group box 1 (HMGB1). This growth inhibitory effect was specific to actively proliferating cells with high cholesterol demand and was reversed when extracellular cholesterol was replenished. Ch25h-expressing CD4+ T cells that received IL-27 and TGF-ß signals became refractory to 25OHC-mediated growth inhibition in vitro. Nonetheless, IL-27­treated T cells negatively affected viability of bystander cells in a paracrine manner, but only if the bystander cells were in the early phases of activation. In mouse models of skin inflammation due to autoreactive T cells or chemically induced hypersensitivity, genetic deletion of Ch25h or Il27ra led to worse outcomes. Thus, Ch25h is an immunoregulatory metabolic switch induced by IL-27 and dampens excess bystander T effector expansion in tissues through its metabolite derivative, 25OHC. This study reveals regulation of cholesterol metabolism as a modality for controlling tissue inflammation and thus represents a mechanism underlying T cell immunoregulatory functions.

Properties of

Mass-separated ^{187}Ta_{114} in a high-spin isomeric state has been produced for the first time by multinucleon transfer reactions, employing an argon gas-stopping cell and laser ionization. Internal γ rays revealed a T_{1/2}=7.3±0.9 s isomer at 1778±1 keV, which decays through a rotational band with perturbations associated with the approach to a prolate-oblate shape transition. Model calculations show less influence from triaxiality compared to heavier elements in the same mass region. The isomer-decay reduced E2 hindrance factor f_{ν}=27±1 supports the interpretation that axial symmetry is approximately conserved.

Efficient two-color two-step laser ionization schemes of λ1∼ 250 nm and λ2 = 307.9 nm for heavy refractory elements-Measurements of ionization cross-sections and hyperfine spectra of tantalum and tungsten.

We demonstrated efficient two-color two-step laser ionization schemes in the combined use of λ1 ∼ 250 nm and λ2 = 307.9 nm, which are applicable to heavy refractory elements with an atomic number in the wide range of Z = 69-78. We investigated newly observed ionization schemes of tantalum and tungsten atoms in an argon-gas-cell-based laser ion source for the efficient ionization of atoms of unstable nuclei through the two-color two-step laser resonance ionization technique. We experimentally determined the ionization cross sections from the measured saturation curves by solving the rate equations for the ground, intermediate, and ionization continuum populations. Hyperfine structures of these elements were also studied to deduce the isotope-shift, pressure-shift, and pressure-broadening in the resonance spectra of the excitation transitions in the argon gas cell. The electronic factor F255 of the excitation transition λ1 = 255.2115 nm between the ground and intermediate states was deduced from the measured isotope shifts of stable 182,183,184,186W isotopes. The ionization schemes investigated here are applicable to extract any isotopes of these elements by considering the measured pressure shift and nuclear isotope shift in optimizing the wavelength λ1.

First Direct Mass Measurements of Nuclides around Z=100 with a Multireflection Time-of-Flight Mass Spectrograph.

The masses of ^{246}Es, ^{251}Fm, and the transfermium nuclei ^{249-252}Md and ^{254}No, produced by hot- and cold-fusion reactions, in the vicinity of the deformed N=152 neutron shell closure, have been directly measured using a multireflection time-of-flight mass spectrograph. The masses of ^{246}Es and ^{249,250,252}Md were measured for the first time. Using the masses of ^{249,250}Md as anchor points for α decay chains, the masses of heavier nuclei, up to ^{261}Bh and ^{266}Mt, were determined. These new masses were compared with theoretical global mass models and demonstrated to be in good agreement with macroscopic-microscopic models in this region. The empirical shell gap parameter δ_{2n} derived from three isotopic masses was updated with the new masses and corroborates the existence of the deformed N=152 neutron shell closure for Md and Lr.

Nerve growth factor regulation and production by macrophages in osteoarthritic synovium.

Nerve growth factor (NGF) functions to modulate osteoarthritis (OA)-associated pain. Although recent studies suggest that tumour necrosis factor (TNF)-α and interleukin (IL)-1ß mediate NGF activity in human synovial fibroblasts, the regulation of NGF expression in human synovial macrophages remains unclear. Here, we examined the role of macrophages in the production and regulation of synovial (SYN) NGF in osteoarthritic knee joints by examining the mRNA expression of TNF-α and IL-1ß in freshly isolated CD14-positive (macrophage-rich fraction) and CD14-negative cells (fibroblast-rich fraction) in synovial tissue from OA patients by quantitative polymerase chain reaction. We also examined the effects of IL-1ß and TNF-α on NGF mRNA expression in cultured CD14-positive (macrophage-rich fraction) and CD14-negative cells (fibroblast-rich fraction). In addition, to examine the contribution of macrophages to NGF, TNF-α and IL-1ß expression, we injected clodronate liposomes systemically into STR/Ort mice, an osteoarthritis animal model, to deplete macrophages. TNF-α and IL-1ß mRNA levels in CD14-positive cells from the SYN of OA patients was significantly higher than that in CD14-negative cells, while NGF expression did not differ markedly between the two cell fractions. In addition, treatment of human cultured CD14-positive and -negative cells with IL-1ß and TNF-α enhanced NGF mRNA and protein levels. Expression of NGF, IL-1ß and TNF-α was also reduced significantly in STR/Ort mice upon macrophage depletion. These findings suggest that IL-1ß and TNF-α regulate NGF expression and production in synovial macrophages and fibroblasts in osteoarthritic joints.

Putting the brakes on reproduction: Implications for conservation, global climate change and biomedicine.

Seasonal breeding is widespread in vertebrates and involves sequential development of the gonads, onset of breeding activities (e.g. cycling in females) and then termination resulting in regression of the reproductive system. Whereas males generally show complete spermatogenesis prior to and after onset of breeding, females of many vertebrate species show only partial ovarian development and may delay onset of cycling (e.g. estrous), yolk deposition or germinal vesicle breakdown until conditions conducive for ovulation and onset of breeding are favorable. Regulation of this "brake" on the onset of breeding remains relatively unknown, but could have profound implications for conservation efforts and for "mismatches" of breeding in relation to global climate change. Using avian models it is proposed that a brain peptide, gonadotropin-inhibitory hormone (GnIH), may be the brake to prevent onset of breeding in females. Evidence to date suggests that although GnIH may be involved in the regulation of gonadal development and regression, it plays more regulatory roles in the process of final ovarian development leading to ovulation, transitions from sexual to parental behavior and suppression of reproductive function by environmental stress. Accumulating experimental evidence strongly suggests that GnIH inhibits actions of gonadotropin-releasing hormones on behavior (central effects), gonadotropin secretion (central and hypophysiotropic effects), and has direct actions in the gonad to inhibit steroidogenesis. Thus, actual onset of breeding activities leading to ovulation may involve environmental cues releasing an inhibition (brake) on the hypothalamo-pituitary-gonad axis.

Species and sex differences in propofol glucuronidation in liver microsomes of humans, monkeys, rats and mice.

Propofol (2,6-diisopropylphenol) is a short-acting anesthetic commonly used in clinical practice, and is rapidly metabolized into glucuronide by UDP-glucuronosyltransferase (UGT). In the present study, propofol glucuronidation was examined in the liver microsomes of male and female humans, monkeys, rats, and mice. The kinetics of propofol glucuronidation by liver microsomes fit the substrate inhibition model for humans and mice, the Hill model for monkeys, and the isoenzyme (biphasic) model for rats. The K(m), V(max), and CL(int) values of human liver microsomes were 50 µM, 5.6 nmol/min/mg protein, and 110 µL/min/mg protein, respectively, for males, and 46 µM, 6.0 nmol/min/mg protein, and 130 µL/min/mg protein, respectively, for females. The rank order of the CL(int) or CL(max) (in vitro clearance) values of liver microsomes was mice humans > monkeys > rats (high-affinity phase) rats (low-affinity phase) in both males and females. Although no significant sex differences were observed in the values of kinetic parameters in any animal species, the in vitro clearance values of liver microsomes were males < females in humans, males = females in rats (low-affinity phase), and males > females in monkeys, rats (high-affinity phase), and mice. These results demonstrated that the kinetic profile of propofol glucuronidation by liver microsomes markedly differed among humans, monkeys, rats, and mice, and suggest that species and sex differences exist in the roles of UGT isoform(s), including UGT1A9, involved in its metabolism.

Long-term outcome in Japanese patients with lupus nephritis.

The objective of this study was to clarify the long-term outcome in patients with lupus nephritis (LN) according to the International Society of Nephrology and Renal Pathology Society classification. This retrospective analysis comprised 186 Japanese patients given a diagnosis of LN by renal specimen with a mean observation period of 12 years. Primary end point was defined as death or end-stage renal disease, and standardized mortality ratios were calculated. Five patients presented with histopathological class I, 62 with II, 21 with III or III+V, 73 with IV or IV+V and 25 with V. Fourteen deaths occurred, corresponding to an overall standardized mortality ratio of 3.59 (95% confidence interval 2.02-5.81, p < 0.0001). Kaplan-Meier analysis revealed a 10-year overall survival of 95.7%. Nephrotic proteinuria (≥3.5 g/day) at baseline was identified as an independent poor prognostic factor for overall survival in Cox regression analysis. Kaplan-Meier analysis revealed a 10-year renal survival as 94.3%. Male gender and nephrotic proteinuria at baseline were identified as independent poor prognostic factors for renal survival in Cox regression analysis. In conclusion, LN was associated with a 3.59-fold increase in mortality compared with the general population. Male gender and nephrotic proteinuria were predictive for poor renal outcome.

In-gas-cell laser ion source for KEK isotope separation system.

The KEK isotope separation system (KISS) is an element-selective isotope separator under development at RIKEN. The in-gas-cell laser ion source is a critical component of the KISS, a gas cell filled with argon gas of 50 kPa enclosed in a vacuum chamber. In the gas cell, nuclear reaction products are stopped (i.e., thermalized and neutralized) and transported by a laminar flow of argon to the ionization region just upstream of the gas outlet, and thereby an element of interest among those reaction products is selectively ionized by two-color resonant laser irradiation. Recently, we succeeded to extract laser-ionized Fe ions by injecting an energetic Fe beam into the gas cell. Recent off- and on-line test results were presented and discussed.

In vitro glucuronidation of propofol in microsomal fractions from human liver, intestine and kidney: tissue distribution and physiological role of UGT1A9.

Propofol (2,6-diisopropylphenol) is intravenously administered for anesthetic induction and maintenance, and is rapidly metabolized into its glucuronide, mainly by UDP-glucuronosyltransferase 1A9 (UGT1A9). In this study, propofol glucuronidation by liver microsomes (HLM), intestinal microsomes (HIM) and kidney microsomes (HKM) of humans were examined. The expression of UGT1A9 protein in HLM, HIM and HKM was analyzed by immunoblotting. The staining band intensities for UGT1A9 of HIM and HKM were 12% and 119% those of HLM, respectively. The kinetics of propofol glucuronidation by HLM and HKM exhibited substrate inhibition, whereas the kinetics by HIM followed the Michaelis-Menten model. The K(m), V(max) and CL(int) values of HLM were 41.8 µM, 5.21 nmol/min/mg protein and 126 µl/min/mg protein, respectively. The K(m) value of HIM was significantly higher (6.7-fold) than that of HLM, and the V(max) and CL(int) values were significantly lower (56% and 8.3%, respectively) than those of HLM. The K(m) value of HKM was comparable to that of HLM, and the V(max) and CL(int) values were significantly higher (2.1- and 3.7-fold, respectively) than those of HLM, respectively. These findings suggest that UGT1A9 expressed in the kidney as well as in the liver plays an important role in propofol glucuronidation. The information gained in this study should contribute to an appropriate use of drugs metabolized by UGT1A9.

Acute respiratory distress in an alpaca.

An alpaca was presented with a history of respiratory difficulty and death. Histology of the phrenic nerves and diaphragm revealed degenerative changes consistent with denervation atrophy, and a diagnosis of diaphragmatic paralysis was established. No gross or histological abnormalities were observed in the spinal cord or other organs. The etiology of the phrenic nerve neuropathy could not be determined. The need to examine phrenic nerves and diaphragm in camelids with respiratory distress is emphasized, as failure to examine these samples will preclude a diagnosis of diaphragmatic paralysis.

Primary primitive neuroectodermal tumor of the conus medullaris in an elderly patient: a case report and review of the literature.

Primary spinal primitive neuroectodermal tumors (PNETs) are very rare conditions. Most of these tumors occur in children and young adults. A 63-year-old man with a primary spinal PNET in the conus medullaris from the L1 to L2 level is presented in this report. The optimal treatment of primary spinal PNETs is yet unknown. Surgical resection, radiation therapy, and chemotherapy have been advocated for the treatment of spinal PNET based on PNETs at other sites. However, the outcome is very poor. There are a few reports of cases with long-term survival and no recurrence. In these patients, en bloc resections were performed.

Non-sentinel lymph node status and prognosis of breast cancer patients with micrometastatic sentinel lymph nodes.

BACKGROUND: The prognostic significance of sentinel lymph node (SLN) micrometastases and the need for axillary lymph node dissection (ALND) on patients with micrometastases in SLNs remain controversial. METHODS: A prospective database of 657 breast cancer patients who underwent SLN biopsy (SLNB) was analyzed. SLNs were detected using a combined method of isosulfan blue dye and small-sized technetium-99m-labeled tin colloid. RESULTS: Micrometastases in SLNs were found in 50 (7.6%) of 657 patients. Twenty-nine (58.0%) of 50 patients with micrometastatic SLNs underwent ALND and no further metastases were found in non-sentinel lymph nodes. Among 21 patients (42.0%) with micrometastatic SLNs who decided to forego ALND, no axillary lymph node recurrence has been observed during a median follow-up time of 47 months. There is no significant difference in recurrence-free survival between the patients with micrometastatic and negative SLNs (p = 0.90). CONCLUSIONS: These data suggest that it may not be necessary to perform ALND on patients with micrometastases in SLNs and that the presence of micrometastases in SLNs may not be associated with prognosis.

Superiority of radioisotope over blue dye for sentinel lymph node detection in breast cancer.

BACKGROUND: Sentinel lymph node biopsy (SLNB) is commonly performed using radioisotopes and/or blue dye. However, it is still undefined which reagent is more suitable for identifying sentinel lymph nodes (SLN). PATIENTS AND METHODS: A consecutive series of 640 breast cancer patients who had undergone SLNB at the Keio University Hospital from 2001 to 2006 was analyzed. The SLN was identified by a combination of technetium-99m tin colloid and isosulfan blue dye. The correlation between clinicopathological factors and the distribution of radioisotopes and blue dye was analyzed. The single metastatic lymph node revealed by axillary lymph node dissection (ALND) is the 'true SLN', and the distribution of radioisotopes and blue dye to the 'true SLN' was also analyzed. RESULTS: Blue-dye- and radioisotope-positive SLN were identified in 79.6 and 94.7% of the patients, respectively. Taken together, SLN were identified in 625 patients (97.7%) by radioisotope and/or blue dye. No significant correlation was observed between clinicopathological features and the distribution of the reagents. ALND found 73 patients with single lymph node metastasis, and 73 'true SLN' were identified by blue dye in 65.7% (48/73), and by radioisotope in 95.9% (70/73) of the cases. CONCLUSION: These data suggest that radioisotopes are superior to blue dye in detecting SLN in breast cancer.

A phase II trial of capecitabine and docetaxel followed by 5-fluorouracil/epirubicin/cyclophosphamide (FEC) as preoperative treatment in women with stage II/III breast cancer.

BACKGROUND: Capecitabine (X) and docetaxel (T) have demonstrated a synergistic effect in preclinical models and a survival benefit in metastatic breast cancer. This study's purpose was to determine the efficacy of X and T followed by 5-fluorouracil/epirubicin/cyclophosphamide (FEC) in the preoperative setting. PATIENTS AND METHODS: Patients with stage II/III breast cancer received four cycles of XT (capecitabine 1650 mg/m(2) on days 1-14 and docetaxel 60 mg/m(2) on day 8 every 3 weeks), followed by four cycles of FEC (5-fluorouracil 500 mg/m(2), epirubicin 90 mg/m(2), and cyclophosphamide 500 mg/m(2) on day 1 every 3 weeks). Primary end points were the pathological complete response (pCR) rate and adverse drug reactions. RESULTS: Seventy-four patients were enrolled and 71 patients were assessable for clinical and pathological responses. The overall response rate was 91.5%. The pCR rate was 14.1% (10 of 71). Grade 3/4 neutropenia was observed in 32.4% of patients. The most common grade 3/4 non-hematologic adverse event was hand-foot syndrome, observed in 11.3% of patients. With 29 months median follow-up, 2-year disease-free survival was estimated 85% for all patients. CONCLUSION: These data indicate that the sequential combination of XT followed by FEC is a well-tolerated, effective neoadjuvant treatment of stage II/III breast cancer.

Close relationship between serum concentrations of 1,5-anhydroglucitol and uric acid in non-diabetic male subjects implies common renal transport system.

BACKGROUND: 1,5-Anhydroglucitol is found in food. We determined factors other than glucosuria that affect serum 1,5-anhydroglucitol (1,5-AG) concentration. METHODS: The relationships between serum 1,5-AG concentration and metabolic parameters were investigated in 158 males with normal glucose tolerance verified by an oral glucose tolerance test. RESULTS: Serum uric acid was positively correlated to 2-h plasma glucose and serum 1,5-AG concentrations. Serum 1,5-AG levels were not different between hyperuricemic and normouricemic subjects, though those with normouricemia had lower 2-h plasma glucose concentrations than subjects with hyperuricemia. The association between 1,5-AG and uric acid in serum was still evident after adjustment with 2-h plasma glucose concentration. Multivariate regression analyses demonstrated that serum uric acid was an independent variable related to serum 1,5-AG and vice versa. CONCLUSIONS: 1,5-AG and uric acid may share in part a common renal tubular transport system, independent of glucose excretion.