Production of bioactive gastrin from the non-endocrine cell lines CHO and COS-7

AbstractWe made a mutated progastrin cDNA construct that contains a cleavage site (-Arg−4-Arg−3-Lys−2 -Arg−1) specific for the Kex2-like endoprotease furin, located ahead of the bioactive gastrin. For expressing the mutated progastrin cDNA, we used two non-endocrine cell lines, CHO and COS-7. CHO cells exhibit amidating enzyme activity and levels of amidation enzyme mRNA as high as those in the pituitary-derived endocrine cell line GH3, whereas COS-7 cells have far less amidating activity and lower amounts of mRNA. Mutant progastrin-expressing CHO cells produced mostly amidated gastrin. Gel filtration showed the size of this gastrin corresponded to that of the synthetic human gastrin-17. In contrast, COS-7 cells produced glycine-extended gastrin and only a small amount of amidated gastrin. The difference in the amount of amidated gastrin products produced by the two non-endocrine cell lines is due to differing amounts of the amidation enzyme contained in each cell line

Accuracy of Pedicle Screw Placement in Scoliosis Surgery: A Comparison between Conventional Computed Tomography-Based and O-Arm-Based Navigation Techniques

Study DesignRetrospective study.PurposeWe compared the accuracy of O-arm-based navigation with computed tomography (CT)-based navigation in scoliotic surgery.Overview of LiteratureNo previous reports comparing the results of O-arm-based navigation with conventional CT-based navigation in scoliotic surgery have been published.MethodsA total of 222 pedicle screws were implanted in 29 patients using CT-based navigation (group C) and 416 screws were implanted in 32 patients using O-arm-based navigation (group O). Postoperative CT was performed to assess the screw accuracy, using the established Neo classification (grade 0: no perforation, grade 1: perforation <2 mm, grade 2: perforation ≥2 and <4, and grade 3: perforation ≥4 mm).ResultsIn group C, 188 (84.7%) of the 222 pedicle screw placements were categorized as grade 0, 23 (10.4%) were grade 1, 11 (5.0%) were grade 2, and 0 were grade 3. In group O, 351 (84.4%) of the 416 pedicle screw placements were categorized as grade 0, 52 (12.5%) were grade 1, 13 (3.1%) were grade 2, and 0 were grade 3. Statistical analysis showed no significant difference in the prevalence of grade 2.3 perforations between groups C and O. The time to position one screw, including registration, was 10.9±3.2 minutes in group C, but was significantly decreased to 5.4±1.1 minutes in group O.ConclusionsO-arm-based navigation facilitates pedicle screw insertion as accurately as conventional CT-based navigation. The use of O-arm-based navigation successfully reduced the time, demonstrating advantages in the safety and accuracy of pedicle screw placement for scoliotic surgery

ALS mutations in the TIA-1 prion-like domain trigger highly condensed pathogenic structures

筋萎縮性側索硬化症（ALS）の発症機構の一端を解明 --タンパク質の高密度な凝縮構造が鍵--. 京都大学プレスリリース. 2022-09-13.T cell intracellular antigen-1 (TIA-1) plays a central role in stress granule (SG) formation by self-assembly via the prion-like domain (PLD). In the TIA-1 PLD, amino acid mutations associated with neurodegenerative diseases, such as amyotrophic lateral sclerosis (ALS) or Welander distal myopathy (WDM), have been identified. However, how these mutations affect PLD self-assembly properties has remained elusive. In this study, we uncovered the implicit pathogenic structures caused by the mutations. NMR analysis indicated that the dynamic structures of the PLD are synergistically determined by the physicochemical properties of amino acids in units of five residues. Molecular dynamics simulations and three-dimensional electron crystallography, together with biochemical assays, revealed that the WDM mutation E384K attenuated the sticky properties, whereas the ALS mutations P362L and A381T enhanced the self-assembly by inducing β-sheet interactions and highly condensed assembly, respectively. These results suggest that the P362L and A381T mutations increase the likelihood of irreversible amyloid fibrillization after phase-separated droplet formation, and this process may lead to pathogenicity

Chiral Monolayers with Achiral Tetrapod Molecules on Highly Oriented Pyrolytic Graphite

金沢大学理工研究域物質化学系The self-assembly of organic molecules at the surface of highly oriented pyrolytic graphite (HOPG) is a promising process for constructing molecular-scale architectures. However, selectable organic molecules are generally restricted to two-dimensional molecules with planar Ï-conjugated structures and alkyl chains. We herein present the formation of self-assembled monolayers of tetrakis(4-ethynylphenyl)methane (TEPM) having a three-dimensional (3D) tetrapod geometry on HOPG, which was achieved by utilizing a simple spin-coating method. The arrangements of TEPM molecules in the monolayers were investigated using frequency-modulation atomic force microscopy (FM-AFM). The resulting subnanometer-resolution FM-AFM images revealed that the TEPM molecules formed linear rows with a periodicity of 0.85 nm oriented in a parallel configuration but with two alternating intervals of 0.7 and 1.0 nm. Moreover, the TEPM monolayers were classified into two chiral types with a relationship of mutual mirror-image symmetry, according to the observed molecular arrangements. Our results demonstrate the capability of TEPM molecules to act as 3D building blocks for the design of molecular-scale architectures at interfaces. Copyright © 2020 American Chemical Society

Gene expression profiling reveals differential effects of sodium selenite, selenomethionine, and yeast-derived selenium in the mouse

The essential trace mineral selenium is an important determinant of oxidative stress susceptibility, with several studies showing an inverse relationship between selenium intake and cancer. Because different chemical forms of selenium have been reported to have varying bioactivity, there is a need for nutrigenomic studies that can comprehensively assess whether there are divergent effects at the molecular level. We examined the gene expression profiles associated with selenomethionine (SM), sodium selenite (SS), and yeast-derived selenium (YS) in the intestine, gastrocnemius, cerebral cortex, and liver of mice. Weanling mice were fed either a selenium-deficient (SD) diet (<0.01 mg/kg diet) or a diet supplemented with one of three selenium sources (1 mg/kg diet, as either SM, SS or YS) for 100 days. All forms of selenium were equally effective in activating standard measures of selenium status, including tissue selenium levels, expression of genes encoding selenoproteins (Gpx1 and Txnrd2), and increasing GPX1 enzyme activity. However, gene expression profiling revealed that SS and YS were similar (and distinct from SM) in both the expression pattern of individual genes and gene functional categories. Furthermore, only YS significantly reduced the expression of Gadd45b in all four tissues and also reduced GADD45B protein levels in liver. Taken together, these results show that gene expression profiling is a powerful technique capable of elucidating differences in the bioactivity of different forms of selenium

A Low Dose of Dietary Resveratrol Partially Mimics Caloric Restriction and Retards Aging Parameters in Mice

Resveratrol in high doses has been shown to extend lifespan in some studies in invertebrates and to prevent early mortality in mice fed a high-fat diet. We fed mice from middle age (14-months) to old age (30-months) either a control diet, a low dose of resveratrol (4.9 mg kg−1 day−1), or a calorie restricted (CR) diet and examined genome-wide transcriptional profiles. We report a striking transcriptional overlap of CR and resveratrol in heart, skeletal muscle and brain. Both dietary interventions inhibit gene expression profiles associated with cardiac and skeletal muscle aging, and prevent age-related cardiac dysfunction. Dietary resveratrol also mimics the effects of CR in insulin mediated glucose uptake in muscle. Gene expression profiling suggests that both CR and resveratrol may retard some aspects of aging through alterations in chromatin structure and transcription. Resveratrol, at doses that can be readily achieved in humans, fulfills the definition of a dietary compound that mimics some aspects of CR

The Hyper Suprime-Cam SSP survey: Overview and survey design

Hyper Suprime-Cam (HSC) is a wide-field imaging camera on the prime focus of the 8.2-m Subaru telescope on the summit of Mauna Kea in Hawaii. A team of scientists from Japan, Taiwan, and Princeton University is using HSC to carry out a 300-night multi-band imaging survey of the high-latitude sky. The survey includes three layers: the Wide layer will cover 1400 deg2 in five broad bands (grizy), with a 5 σ point-source depth of r ≈ 26. The Deep layer covers a total of 26 deg2 in four fields, going roughly a magnitude fainter, while the UltraDeep layer goes almost a magnitude fainter still in two pointings of HSC (a total of 3.5 deg2). Here we describe the instrument, the science goals of the survey, and the survey strategy and data processing. This paper serves as an introduction to a special issue of the Publications of the Astronomical Society of Japan, which includes a large number of technical and scientific papers describing results from the early phases of this survey

Cytocompatible polyion complex gel of poly(Pro-Hyp-Gly) for simultaneous rat bone marrow stromal cell encapsulation

Polyion complex (PIC) gel of poly(Pro-Hyp-Gly) was successfully fabricated by simply mixing polyanion and polycation derivatives of poly(Pro-Hyp-Gly), a collagen-like polypeptide. The polyanion, succinylated poly(Pro-Hyp-Gly), and the polycation, arginylated poly(Pro-Hyp-Gly), contain carboxy (pKa = 5.2) and guanidinium (pKa = 12.4) groups, respectively. Mixing the polyanion and the polycation at physiological pH (pH = 7.4) resulted in PIC gel. The hydrogel formation was optimum at an equimolar ratio of carboxy to guanidinium groups, suggesting that ionic interaction is the main determinant for the hydrogel formation. The hydrogel was successfully used for simultaneous rat bone marrow stromal cell encapsulation. The encapsulated cells survived and proliferated within the hydrogel. In addition, the cells exhibited different morphology in the hydrogel compared with cells cultured on a tissue culture dish as a two-dimensional (2D) control. At day one, a round morphology and homogeneous single cell distribution were observed in the hydrogel. In contrast, the cells spread and formed a fibroblast-like morphology on the 2D control. After three days, the cells in the hydrogel maintained their morphology and some of them formed multicellular aggregates, which is similar to cell morphology in an in vivo microenvironment. These results suggest that the PIC gel of poly(Pro-Hyp-Gly) can serve as a cytocompatible three-dimensional scaffold for stem cell encapsulation, supporting their viability, proliferation, and in vivo-like behavior