Multidrug and toxin extrusion 1 (MATE1) and MATE2‐K are H+/organic cation exchangers mediating the efflux of cationic drugs into the urine. N‐methylnicotinamide (NMN) was found to be an endogenous ...substrate of MATE1 (Michaelis constant (Km) 301 ± 18 µmol/l) and MATE2‐K (Km 422 ± 63 µmol/l) as well as a basolateral influx transporter, organic cation transporter 2 (Km 318 ± 29 µmol/l). A potent MATE inhibitor, pyrimethamine, competitively inhibited the uptake by MATE1 and MATE2‐K with inhibition constant (Ki) values of 83 ± 15 and 56 ± 11 nmol/l, respectively. The uptake of NMN by human kidney brush border membrane vesicles with a H+ gradient was saturable (Km 360 ± 55 µmol/l) and completely inhibited by pyrimethamine. The renal clearance of endogenous NMN was 403 ± 61 in healthy male subjects, and it was significantly decreased to 119 ± 16 ml/min/kg by an oral dose of pyrimethamine (50 mg). These results support the utility of NMN as an endogenous in vivo probe for investigating MATE1 and MATE2‐K in humans.
Clinical Pharmacology & Therapeutics (2012); 92 5, 635–641. doi:10.1038/clpt.2012.138
Extreme ultraviolet and X-ray free-electron lasers (FELs) produce short-wavelength pulses with high intensity, ultrashort duration, well-defined polarization and transverse coherence, and have been ...utilized for many experiments previously possible only at long wavelengths: multiphoton ionization, pumping an atomic laser and four-wave mixing spectroscopy. However one important optical technique, coherent control, has not yet been demonstrated, because self-amplified spontaneous emission FELs have limited longitudinal coherence. Single-colour pulses from the FERMI seeded FEL are longitudinally coherent, and two-colour emission is predicted to be coherent. Here, we demonstrate the phase correlation of two colours, and manipulate it to control an experiment. Light of wavelengths 63.0 and 31.5 nm ionized neon, and we controlled the asymmetry of the photoelectron angular distribution by adjusting the phase, with a temporal resolution of 3 as. This opens the door to new short-wavelength coherent control experiments with ultrahigh time resolution and chemical sensitivity.
Irreversible oxidation of Cys residues to sulfinic/sulfonic forms typically impairs protein function. We found that persulfidation (CysSSH) protects Cys from irreversible oxidative loss of function ...by the formation of CysSSO
H derivatives that can subsequently be reduced back to native thiols. Reductive reactivation of oxidized persulfides by the thioredoxin system was demonstrated in albumin, Prx2, and PTP1B. In cells, this mechanism protects and regulates key proteins of signaling pathways, including Prx2, PTEN, PTP1B, HSP90, and KEAP1. Using quantitative mass spectrometry, we show that (i) CysSSH and CysSSO
H species are abundant in mouse liver and enzymatically regulated by the glutathione and thioredoxin systems and (ii) deletion of the thioredoxin-related protein TRP14 in mice altered CysSSH levels on a subset of proteins, predicting a role for TRP14 in persulfide signaling. Furthermore, selenium supplementation, polysulfide treatment, or knockdown of TRP14 mediated cellular responses to EGF, suggesting a role for TrxR1/TRP14-regulated oxidative persulfidation in growth factor responsiveness.
Human epidermal growth factor receptor2/Neu, which is overexpressed in about 30% of human breast cancers, transduces growth signals in large part via the Ras-Raf-MEK-ERK pathway. Nevertheless, it is ...a matter of controversy whether high ERK activity in breast cancer tissues correlates with better or worse prognosis, leaving the role of ERK activity in the progression of breast cancers unresolved. To address this issue, we live-imaged ERK activity in mammary tumors developed in mouse mammary tumor virus-Neu transgenic mice, which had been crossed with transgenic mice expressing a Förster resonance energy transfer biosensor for ERK. Observation of the tumor by two-photon microscopy revealed significant heterogeneity in ERK activity among the mammary tumor cells. The level of ERK activity in each cell was stable up to several hours, implying a robust mechanism that maintained the ERK activity within a limited range. By sorting the mammary tumor cells on the basis of their ERK activity, we found that ERK(high) cells less efficiently generated tumorspheres in vitro and tumors in vivo than did ERK(low) cells. In agreement with this finding, the expressions of the cancer stem cell markers CD49f, CD24 and CD61 were decreased in ERK(high) cells. These observations suggest that high ERK activity may suppress the self-renewal of mammary cancer stem cells.
Epilepsies are common neurological disorders and genetic factors contribute to their pathogenesis. Copy number variations (CNVs) are increasingly recognized as an important etiology of many human ...diseases including epilepsy. Whole‐exome sequencing (WES) is becoming a standard tool for detecting pathogenic mutations and has recently been applied to detecting CNVs. Here, we analyzed 294 families with epilepsy using WES, and focused on 168 families with no causative single nucleotide variants in known epilepsy‐associated genes to further validate CNVs using 2 different CNV detection tools using WES data. We confirmed 18 pathogenic CNVs, and 2 deletions and 2 duplications at chr15q11.2 of clinically unknown significance. Of note, we were able to identify small CNVs less than 10 kb in size, which might be difficult to detect by conventional microarray. We revealed 2 cases with pathogenic CNVs that one of the 2 CNV detection tools failed to find, suggesting that using different CNV tools is recommended to increase diagnostic yield. Considering a relatively high discovery rate of CNVs (18 out of 168 families, 10.7%) and successful detection of CNV with <10 kb in size, CNV detection by WES may be able to surrogate, or at least complement, conventional microarray analysis.
Whole‐exome sequencing (WES) was performed in a total of 294 families with epilepsy. Then, WES‐based copy number variation (CNV) detection in 168 families were conducted after excluding 126 families with causative single nucleotide variants, and 18 families with pathogenic CNVs were identified. CNVs were detected in 2 ways: (1) 2‐step detection: eXome Hidden Markov Model (XHMM) and subsequent Nord's method (left in a dotted box) and (2) Nord's method targeting 303 epilepsy genes (right in a dotted box). Seventeen and one pathogenic CNVs were detected by methods (1) and (2), respectively.
Background
JTT-751 is a novel phosphate binder containing ferric citrate as the active ingredient.
Methods
In this Phase 3, multicenter, randomized, open-label, parallel-group study, we compared the ...efficacy and safety of JTT-751 and sevelamer hydrochloride in patients undergoing hemodialysis. A total of 230 patients with a serum phosphate ≥1.97 and <3.23 mmol/L were randomized to JTT-751 (dose adjusted between 1.5 and 6.0 g/day) or sevelamer hydrochloride (dose adjusted between 3.0 and 9.0 g/day) for 12 weeks. The primary outcome was change in serum phosphate from baseline to end of treatment. Secondary outcomes included the changes in corrected serum calcium and intact parathyroid hormone (PTH). The changes in ferritin, transferrin saturation and erythropoiesis-stimulating agent dose were additional outcomes.
Results
Changes in serum phosphate at the end of treatment were −0.82 mmol/L in the JTT-751 group and −0.78 mmol/L in the sevelamer group, establishing non-inferiority of JTT-751 compared with sevelamer (least squares mean, −0.03 mmol/L; 95% confidence interval, −0.13 to 0.07 mmol/L). Corrected serum calcium increased and PTH decreased from baseline within both groups; changes between groups were similar. Gastrointestinal disorders were the most common adverse events in both groups; the incidence of diarrhea was higher in the JTT-751 group, while constipation occurred frequently in the sevelamer group. Treatment with JTT-751 resulted in significant relative increases in serum ferritin and transferrin saturation.
Conclusions
Efficacy and safety of JTT-751 was comparable to sevelamer in patients on hemodialysis with hyperphosphatemia. Differential adverse effects were observed; biochemical markers of iron status increased in patients treated with JTT-751.
Trial registration number
CTI-111433 (The Japan Pharmaceutical Information Center at: http//www.clinicaltrials.jp). Date of registration: 7 March 2011.
As presently conceptualised, the artificial placenta (AP) is an experimental life support platform for extremely preterm infants (i.e. 400-600 g; 21–23+6 weeks of gestation) born at the border of ...viability. It is based around the oxygenation of the periviable fetus using gas-exchangers connected to the fetal vasculature. In this system, the lung remains fluid-filled and the fetus remains in a quiescent state. The AP has been in development for some sixty years. Over this time, animal experimental models have evolved iteratively from employing external pump-driven systems used to support comparatively mature fetuses (generally goats or sheep) to platforms driven by the fetal heart and used successfully to maintain extremely premature fetuses weighing around 600 g. Simultaneously, sizable advances in neonatal and obstetric care mean that the nature of a potential candidate patient for this therapy, and thus the threshold success level for justifying its adoption, have both changed markedly since this approach was first conceived.
Five landmark breakthroughs have occurred over the developmental history of the AP: i) the first human studies reported in the 1950's; ii) foundation animal studies reported in the 1960's; iii) the first extended use of AP technology combined with fetal pulmonary resuscitation reported in the 1990s; iv) the development of AP systems powered by the fetal heart reported in the 2000's; and v) the adaption of this technology to maintain extremely preterm fetuses (i.e. 500-600 g body weight) reported in the 2010's. Using this framework, the present paper will provide a review of the developmental history of this long-running experimental system and up-to-date assessment of the published field today.
With the apparent acceleration of AP technology towards clinical application, there has been an increase in the attention paid to the field, along with some inaccurate commentary regarding its potential application and merits. Additionally, this paper will address several misrepresentations regarding the potential application of AP technology that serve to distract from the significant potential of this approach to greatly improve outcomes for extremely preterm infants born at or close to the present border of viability.
•The artificial placenta is an experimental life support platform for extremely preterm infants.•The artificial placenta concept has been in development for over 60 years.•Significant improvements have been made in hardware performance.•Significant challenges remain to be overcome before clinical use can occur.
The aim of the present study was to observe the endoscopic characteristics of cells on the surface layer of superficial esophageal carcinomas in vivo using an endocytoscopy system and to compare the ...findings with those in normal squamous epithelium.
Superficial esophageal cancers in 12 patients were examined with methylene blue staining using an endocytoscopy system.
The endocytoscopy system and methylene blue staining made it possible to observe cells on the surface of the squamous epithelium in normal esophageal mucosa. Normal cells were arranged homogeneously, and the nucleus cytoplasm ratio was uniform and low. In esophageal cancers, the density of cells was found to be much greater than that in normal squamous epithelium. The cell distribution was also irregular and the cells were extremely heterogeneous, with the nuclei having different staining, size, and shape characteristics. The nucleus cytoplasm ratio was also very irregular.
Examining esophageal tissue using the endocytoscopy system described here makes it possible to observe detailed histological alterations in esophageal lesions in vivo.
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