501 research outputs found
A bacterial enzyme degrading the model lignin compound β-etherase is a member of the glutathione-S-transferase superfamily
AbstractCleavage of β-aryl ether linkages is essential in lignin degradation. We identified another β-etherase gene (ligF), which contains an open reading frame of 771 bp and lies between genes coding Cα-dehydrogenase (ligD) and β-etherase (ligE). The β-etherase activity of LigF expressed in Escherichia coli was more than 80 times as high as that of LigE. ligF and ligE are homologous to glutathione-S-transferase, and upon addition of glutathione a remarkable acceleration of β-etherase activity was found in E. coli carrying ligF. It is concluded that LigF plays a central role in β-aryl ether cleavage and that glutathione is the hydrogen donor in this reaction
A Novel CLEIA for FGF23
Introduction: Measurement of fibroblast growth factor 23 (FGF23) has been reported to be clinically useful for the differential diagnosis of chronic hypophosphatemia. However, assays for research use only are available in Japan. Thus, the objective of this study was to examine the clinical utility of a novel and automated chemiluminescent enzyme immunoassay for the measurement of FGF23.
Materials and Methods: Participants were recruited from July 2015 to January 2017 at six facilities in Japan. Thirty-eight patients with X-linked hypophosphatemic rickets (XLH; 15 males, 23 females, age 0–66 years), five patients with tumour-induced osteomalacia (TIO; 3 males, 2 females, age 60–73 years), and twenty-two patients with hypophosphatemia (11 males, 11 females, age 1–75 years) caused due to other factors participated in this study.
Results: With the clinical cut-off value of FGF23 at 30.0 pg/mL indicated in the Diagnostic Guideline of Rickets/Osteomalacia in Japan, the sensitivity and specificity of FGF23-related hypophosphatemic rickets/osteomalacia without vitamin D deficiency (disease group-1) were 100% and 81.8%, respectively, which distinguished it from non-FGF23-related hypophosphatemia (disease group-2). Furthermore, the diagnostic sensitivity of FGF23-related hypophosphatemia with vitamin D deficiency remained at 100%. Among the four patients with FGF23 levels ≥ 30.0 pg/mL in disease group-2, two patients with relatively higher FGF23 values were suspected to have genuine FGF23-related hypophosphatemia, due to the ectopic production of FGF23 in pulmonary and prostate small cell carcinomas.
Conclusion: The novel FGF23 assay tested in this study is useful for the differential diagnosis of hypophosphatemic rickets/osteomalacia in a clinical setting
Attenuated response to liver injury in moesin-deficient mice: Impaired stellate cell migration and decreased fibrosis
AbstractHepatic stellate cells (HSCs) respond to injury with a coordinated set of events (termed activation), which includes migration and upregulation of matrix protein production. Cell migration requires an intact actin cytoskeleton that is linked to the plasma membrane by ezrin–radixin–moesin (ERM) proteins. We have previously found that the linker protein in HSCs is exclusively moesin. Here, we describe HSC migration and fibrogenesis in moesin-deficient mice. We developed an acute liver injury model that involved focal thermal denaturation and common bile duct ligation. HSC migration and collagen deposition were assessed by immunohistology and quantitative real-time PCR. Activated HSCs were isolated from wild-type or moesin-deficient mice for direct examination of migration. Activated HSCs from wild-type mice were positive for moesin. Migration of moesin-deficient HSCs was significantly reduced. In a culture assay, 22.1% of normal HSCs migrated across a filter in 36h. In contrast, only 1.3% of activated moesin-deficient HSCs migrated. Collagen deposition around the injury area similarly was reduced in moesin-deficient liver. The linker protein moesin is essential for HSC activation and migration in response to injury. Fibrogenesis is coupled to migration and reduced in moesin-deficient mice. Agents that target moesin may be beneficial for chronic progressive fibrosis
Successful management of a large lingual foregut duplication cyst with an ex-utero intrapartum treatment procedure
Foregut duplication cysts are rare congenital choristomas that sometimes cause feeding and respiratory problems, depending on their size and location. Prenatal ultrasonography revealed a fetus with a large oral cystic mass and polyhydramnios. Differential diagnoses included ranula, lymphangioma, and thyroglossal duct cysts. A multidisciplinary fetal care team devised an airway management plan. We performed ex-utero intrapartum treatment (EXIT) because the origin and patency of the fetal airway could not be confirmed using fetal magnetic resonance imaging. At delivery, a lingual cyst occupied the oral cavity and protruded from the mouth. Oral intubation was performed after the aspiration of the cyst during the EXIT. On day 16, the cyst was completely excised. Histopathological examination revealed a foregut duplication cyst lined by the respiratory and gastric epithelium. Lingual foregut duplication cysts pose a risk for airway obstruction. For prenatally diagnosed cases, coordination of a multidisciplinary fetal care team and early discussions can optimize the plan for prenatal management, including the EXIT procedure
Spectral evolution of GRB 060904A observed with Swift and Suzaku -- Possibility of Inefficient Electron Acceleration
We observed an X-ray afterglow of GRB 060904A with the Swift and Suzaku
satellites. We found rapid spectral softening during both the prompt tail phase
and the decline phase of an X-ray flare in the BAT and XRT data. The observed
spectra were fit by power-law photon indices which rapidly changed from to within a few hundred
seconds in the prompt tail. This is one of the steepest X-ray spectra ever
observed, making it quite difficult to explain by simple electron acceleration
and synchrotron radiation. Then, we applied an alternative spectral fitting
using a broken power-law with exponential cutoff (BPEC) model. It is valid to
consider the situation that the cutoff energy is equivalent to the synchrotron
frequency of the maximum energy electrons in their energy distribution. Since
the spectral cutoff appears in the soft X-ray band, we conclude the electron
acceleration has been inefficient in the internal shocks of GRB 060904A. These
cutoff spectra suddenly disappeared at the transition time from the prompt tail
phase to the shallow decay one. After that, typical afterglow spectra with the
photon indices of 2.0 are continuously and preciously monitored by both XRT and
Suzaku/XIS up to 1 day since the burst trigger time. We could successfully
trace the temporal history of two characteristic break energies (peak energy
and cutoff energy) and they show the time dependence of while the following afterglow spectra are quite stable. This fact
indicates that the emitting material of prompt tail is due to completely
different dynamics from the shallow decay component. Therefore we conclude the
emission sites of two distinct phenomena obviously differ from each other.Comment: 19 pages, 9 figures, accepted for publication in PASJ (Suzaku 2nd
Special Issue
Pyridoxal 5′-phosphate and related metabolites in hypophosphatasia: Effects of enzyme replacement therapy
Objective
To investigate the utility of serum pyridoxal 5′-phosphate (PLP), pyridoxal (PL), and 4-pyridoxic acid (PA) as a diagnostic marker of hypophosphatasia (HPP) and an indicator of the effect of, and patient compliance with, enzyme replacement therapy (ERT), we measured PLP, PL, and PA concentrations in serum samples from HPP patients with and without ERT.
Methods
Blood samples were collected from HPP patients and serum was frozen as soon as possible (mostly within one hour). PLP, PL, and PA concentrations were analyzed using high-performance liquid chromatography with fluorescence detection after pre-column derivatization by semicarbazide. We investigated which metabolites are associated with clinical phenotypes and how these metabolites change with ERT.
Results
Serum samples from 20 HPP patients were analyzed. The PLP-to-PL ratio and PLP concentration were elevated in all HPP patients. They correlated negatively with serum alkaline phosphatase (ALP) activity and showed higher values in more severe phenotypes (perinatal severe and infantile HPP) compared with other phenotypes. PL concentration was reduced only in perinatal severe HPP. ERT reduced the PLP-to-PL ratio to mildly reduced or low-normal levels and the PLP concentration was reduced to normal or mildly elevated levels. Urine phosphoethanolamine (PEA) concentration did not return to normal levels with ERT in most patients.
Conclusions
The serum PLP-to-PL ratio is a better indicator of the effect of ERT for HPP than serum PLP and urine PEA concentrations, and a PLP-to-PL ratio of <4.0 is a good indicator of the effect of, and patient compliance with, ERT
Brown adipose tissue dysfunction promotes heart failure via a trimethylamine N-oxide-dependent mechanism.
Low body temperature predicts a poor outcome in patients with heart failure, but the underlying pathological mechanisms and implications are largely unknown. Brown adipose tissue (BAT) was initially characterised as a thermogenic organ, and recent studies have suggested it plays a crucial role in maintaining systemic metabolic health. While these reports suggest a potential link between BAT and heart failure, the potential role of BAT dysfunction in heart failure has not been investigated. Here, we demonstrate that alteration of BAT function contributes to development of heart failure through disorientation in choline metabolism. Thoracic aortic constriction (TAC) or myocardial infarction (MI) reduced the thermogenic capacity of BAT in mice, leading to significant reduction of body temperature with cold exposure. BAT became hypoxic with TAC or MI, and hypoxic stress induced apoptosis of brown adipocytes. Enhancement of BAT function improved thermogenesis and cardiac function in TAC mice. Conversely, systolic function was impaired in a mouse model of genetic BAT dysfunction, in association with a low survival rate after TAC. Metabolomic analysis showed that reduced BAT thermogenesis was associated with elevation of plasma trimethylamine N-oxide (TMAO) levels. Administration of TMAO to mice led to significant reduction of phosphocreatine and ATP levels in cardiac tissue via suppression of mitochondrial complex IV activity. Genetic or pharmacological inhibition of flavin-containing monooxygenase reduced the plasma TMAO level in mice, and improved cardiac dysfunction in animals with left ventricular pressure overload. In patients with dilated cardiomyopathy, body temperature was low along with elevation of plasma choline and TMAO levels. These results suggest that maintenance of BAT homeostasis and reducing TMAO production could be potential next-generation therapies for heart failure.We thank Kaori Yoshida, Keiko Uchiyama, Satomi Kawai, Naomi Hatanaka, Yoko Sawaguchi, Runa Washio,
Takako Ichihashi, Nanako Koike, Keiko Uchiyama, Masaaki Nameta (Niigata University), Kaori Igarashi, Kaori
Saitoh, Keiko Endo, Hiroko Maki, Ayano Ueno, Maki Ohishi, Sanae Yamanaka, Noriko Kagata (Keio University)
for their excellent technical assistance, C. Ronald Kahn (Joslin Diabetes Center and Harvard Medical School)
for providing the BAT cell line, Evan Rosen (Harvard Medical School) for providing us Ucp-Cre mice, Kosuke
Morikawa (Kyoto University), Tomitake Tsukihara (University of Hyogo) and Shinya Yoshikawa (University of
Hyogo) for their professional opinions and suggestions. Tis work was supported by a Grant-in-Aid for Scientifc Research (A) (20H00533) from MEXT, AMED under Grant Numbers JP20ek0210114, and AMED-CREST
under Grant Number JP20gm1110012, and Moonshot Research and Development Program (21zf0127003s0201),
MEXT Supported Program for the Strategic Research Foundation at Private Universities Japan, Private University
Research Branding Project, and Leading Initiative for Excellent Young Researchers, and grants from the Takeda
Medical Research Foundation, the Vehicle Racing Commemorative Foundation, Ono Medical Research Foundation, and the Suzuken Memorial Foundation (to T.M.). Support was also provided by a Grants-in-Aid for Young
Scientists (Start-up) (26893080), and grants from the Uehara Memorial Foundation, Kowa Life Science Foundation, Manpei Suzuki Diabetes Foundation, SENSHIN Medical Research Foundation, ONO Medical Research
Foundation, Tsukada Grant for Niigata University Medical Research, Te Nakajima Foundation, SUZUKEN
memorial foundation, HOKUTO Corporation, Mochida Memorial Foundation for Medical & Pharmaceutical
Research, Grants-in-Aid for Encouragement of Young Scientists (A) (16H06244), Daiichi Sankyo Foundation of
Life Science, AMED Project for Elucidating and Controlling Mechanisms of Aging and Longevity under Grant
Number JP17gm5010002, JP18gm5010002, JP19gm5010002, JP20gm5010002, JP21gm5010002, Astellas Foundation for Research on Metabolic Disorders, Research grant from Naito Foundation, Te Japan Geriatrics Society
(to I.S.); by a Grant-in-Aid for Scientifc Research (C) (19K08974), Yujin Memorial Grant, Sakakibara Memorial
Research Grant from Te Japan Research Promotion Society for Cardiovascular Diseases, TERUMO Life Science Foundation, Kanae Foundation (to Y.Y.), JST ERATO (JPMJER1902), AMED-CREST (JP20gm1010009),
the Takeda Science Foundation, the Food Science Institute Foundation (to S.F.), and by a grant from Bourbon
(to T.M., I.S. and Y.Y.).S
Review Article : Feudalism or Absolute Monarchism?
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/68809/2/10.1177_009770049001600304.pd
- …