| 1. |
- Bernal, Ximena E., et al.
(författare)
-
Empowering Latina scientists
- 2019
-
Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 363:6429, s. 825-826
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 2. |
- Brate, Jon, et al.
(författare)
-
Unicellular Origin of the Animal MicroRNA Machinery
- 2018
-
Ingår i: Current Biology. - : Elsevier BV. - 0960-9822 .- 1879-0445. ; 28:20, s. 3288-
-
Tidskriftsartikel (refereegranskat)abstract
- The emergence of multicellular animals was associated with an increase in phenotypic complexity and with the acquisition of spatial cell differentiation and embryonic development. Paradoxically, this phenotypic transition was not paralleled by major changes in the underlying developmental toolkit and regulatory networks. In fact, most of these systems are ancient, established already in the unicellular ancestors of animals [1-5]. In contrast, the Microprocessor protein machinery, which is essential for microRNA (miRNA) biogenesis in animals, as well as the miRNA genes themselves produced by this Microprocessor, have not been identified outside of the animal kingdom [6]. Hence, the Microprocessor, with the key proteins Pasha and Drosha, is regarded as an animal innovation [7-9]. Here, we challenge this evolutionary scenario by investigating unicellular sister lineages of animals through genomic and transcriptomic analyses. We identify in Ichthyosporea both Drosha and Pasha (DGCR8 in vertebrates), indicating that the Microprocessor complex evolved long before the last common ancestor of animals, consistent with a pre-metazoan origin of most of the animal developmental gene elements. Through small RNA sequencing, we also discovered expressed bona fide miRNA genes in several species of the ichthyosporeans harboring the Microprocessor. A deep, pre-metazoan origin of the Microprocessor and miRNAs comply with a view that the origin of multicellular animals was not directly linked to the innovation of these key regulatory components.
|
|
| 3. |
|
|
| 4. |
- Duret-Thual, Claude, et al.
(författare)
-
Assessment of the hydrogen induced stress cracking resistance of precipitation hardened nickel-based alloys using the slow strain rate tensile test method - Review of a three years test program
- 2019
-
Ingår i: NACE - International Corrosion Conference SeriesVolume 2019-March, 2019, Article number 13284Corrosion Conference and Expo 2019; Nashville; United States; 24 March 2019 through 28 March 2019. - : National Assoc. of Corrosion Engineers International.
-
Konferensbidrag (refereegranskat)abstract
- Precipitation Hardened (PH) Ni-based alloys have proved to be sensitive to Hydrogen Induced Stress Cracking (HISC), and HISC related failures in the Oil and Gas industry have been experienced in the case of UNS N07718, UNS N07725 and UNS N07716. Slow Strain Rate Tensile (SSRT) tests conducted under cathodic polarization gave encouraging results as a means to evaluate HISC resistance when applied to UNS N07718, enabling the discrimination of acceptable and unacceptable microstructures as according to API 6A CRA. As a consequence, an extensive test program was launched on several PH Ni grades, a program sponsored by several petroleum companies. The main objectives of this program were to develop a test method to allow for the evaluation of HISC resistance, in order to rank materials and possibly define acceptance criteria for each material, and also to better understand the relationship between microstructure and HISC resistance. Twenty-eight industrial heats of PH Ni Alloys of eight material grades were fully characterized (microstructure, mechanical properties) and evaluated using the SSRT test method under applied cathodic polarization. The yield strength of the materials tested was in the range 120 to 160 ksi. The quantitative susceptibility of the materials to HISC was established using the plastic elongation pCP and the plastic elongation ratio pCP/ pinert. Test results showed that some PH alloys that exhibited acceptable microstructures, in accordance with API 6ACRA, did not necessarily exhibit high plastic elongation ratios. The need to implement HISC related tests in the selection of PH Ni base alloys for Oil and Gas applications is indicated
|
|
| 5. |
- Ehrencrona, Erik, et al.
(författare)
-
The IgGFc-binding protein FCGBP is secreted with all GDPH sequences cleaved but maintained by interfragment disulfide bonds
- 2021
-
Ingår i: Journal of Biological Chemistry. - : Elsevier BV. - 0021-9258. ; 297:1
-
Tidskriftsartikel (refereegranskat)abstract
- Mucus forms an important protective barrier that minimizes bacterial contact with the colonic epithelium. Intestinal mucus is organized in a complex network with several specific proteins, including the mucin-2 (MUC2) and the abundant IgGFc-binding protein, FCGBP. FCGBP is expressed in all intestinal goblet cells and is secreted into the mucus. It is comprised of repeated von Willebrand D (vWD) domain assemblies, most of which have a GDPH amino acid sequence that can be autocatalytically cleaved, as previously observed in the mucins MUC2 and mucin-5AC. However, the functions of FCGBP in the mucus are not understood. We show that all vWD domains of FCGBP with a GDPH sequence are cleaved and that these cleavages occur early during biosynthesis in the endoplasmic reticulum. All cleaved fragments, however, remain connected via a disulfide bond within each vWD domain. This cleavage generates a C-terminal-reactive Asp-anhydride that could react with other molecules, such as MUC2, but this was not observed. Quantitative analyses by MS showed that FCGBP was mainly soluble in chaotropic solutions, whereas MUC2 was insoluble, and most of the secreted FCGBP was not covalently bound to MUC2. Although FCGBP has been suggested to bind immunoglobulin G, we were unable to reproduce this binding in vitro using purified proteins. In conclusion, while the function of FCGBP is still unknown, our results suggest that it does not contribute to covalent crosslinking in the mucus, nor incorporate immunoglobulin G into mucus, instead the single disulfide bond linking each fragment could mediate controlled dissociation.
|
|
| 6. |
- Ermund, Anna, et al.
(författare)
-
The normal trachea is cleaned by MUC5B mucin bundles from the submucosal glands coated with the MUC5AC mucin
- 2017
-
Ingår i: Biochemical and Biophysical Research Communications - BBRC. - : Elsevier BV. - 0006-291X .- 1090-2104. ; 492:3, s. 331-337
-
Tidskriftsartikel (refereegranskat)abstract
- To understand the mucociliary clearance system, mucins were visualized by light, confocal and electron microscopy, and mucus was stained by Alcian blue and tracked by video microscopy on tracheal explants of newborn piglets. We observed long linear mucus bundles that appeared at the submucosal gland openings and were transported cephalically. The mucus bundles were shown by mass spectrometry and immunostaining to have a core made of MUC5B mucin and were coated with MUC5AC mucin produced by surface goblet cells. The transport speed of the bundles was slower than the airway surface liquid flow. We suggest that the goblet cell MUC5AC mucin anchors the mucus bundles and thus controls their transport. Normal clearance of the respiratory tree of pigs and humans, both rich in submucosal glands, is performed by thick and long mucus bundles. (C) 2017 The Authors. Published by Elsevier Inc.
|
|
| 7. |
- Gallego, Pablo, et al.
(författare)
-
The intestinal MUC2 mucin C-terminus is stabilized by an extra disulfide bond in comparison to von Willebrand factor and other gel-forming mucins
- 2023
-
Ingår i: Nature communications. - 2041-1723. ; 14
-
Tidskriftsartikel (refereegranskat)abstract
- The MUC2 mucin polymer is the main building unit of the intestinal mucus layers separating intestinal microbiota from the host epithelium. The MUC2 mucin is a large glycoprotein with a C-terminal domain similar to the MUC5AC and MUC5B mucins and the von Willebrand factor (VWF). A structural model of the C-terminal part of MUC2, MUC2-C, was generated by combining Cryo-electron microscopy, AlphaFold prediction, information of its glycosylation, and small angle X-ray scattering information. The globular VWD4 assembly in the N-terminal of MUC2-C is followed by 3.5 linear VWC domains that form an extended flexible structure before the C-terminal cystine-knot. All gel-forming mucins and VWF form tail-tail disulfide-bonded dimers in their C-terminal cystine-knot domain, but interestingly the MUC2 mucin has an extra stabilizing disulfide bond on the N-terminal side of the VWD4 domain, likely essential for a stable intestinal mucus barrier.
|
|
| 8. |
- Recktenwald, Christian V, et al.
(författare)
-
The structure of the second CysD domain of MUC2 and role in mucin organization by transglutaminase-based cross-linking
- 2024
-
Ingår i: Cell Reports. - 2211-1247. ; 43
-
Tidskriftsartikel (refereegranskat)abstract
- The MUC2 mucin protects the colonic epithelium by a two-layered mucus with an inner attached bacteria-free layer and an outer layer harboring commensal bacteria. CysD domains are 100 amino-acid-long sequences containing 10 cysteines that separate highly O-glycosylated proline, threonine, serine (PTS) regions in mucins. The structure of the second CysD, CysD2, of MUC2 is now solved by nuclear magnetic resonance. CysD2 shows a stable stalk region predicted to be partly covered by adjacent O-glycans attached to neighboring PTS sequences, whereas the CysD2 tip with three flexible loops is suggested to be well exposed. It shows transient dimer interactions at acidic pH, weakened at physiological pH. This transient interaction can be stabilized in vitro and in vivo by transglutaminase 3-catalyzed isopeptide bonds, preferring a specific glutamine residue on one flexible loop. This covalent dimer is modeled suggesting that CysD domains act as connecting hubs for covalent stabilization of mucins to form a protective mucus.
|
|
| 9. |
- Salvatori, I., et al.
(författare)
-
Assessment of the hydrogen induced stress cracking resistance of precipitation hardened nickel-based alloys using the slow strain rate tensile test method : Influence of microstructure
- 2019
-
Ingår i: NACE - International Corrosion Conference SeriesVolume 2019-March, 2019, Article number 13365Corrosion Conference and Expo 2019; Nashville; United States; 24 March 2019 through 28 March 2019. - : National Assoc. of Corrosion Engineers International.
-
Konferensbidrag (refereegranskat)abstract
- Within the framework of a Joint Industrial Project sponsored by several petroleum companies, the behavior of several Precipitation Hardened (PH) Ni-based alloys with respect to Hydrogen Induced Stress Cracking (HISC) resistance was studied, using the Slow Strain Rate Tensile (SSRT) test method conducted under hydrogen charging conditions (applying a constant cathodic current density throughout the test). Among the test materials, several industrial Heats of UNS N07718, UNS N09945/945X, UNS N09925, UNS N09935, UNS N07725 and UNS N07716 were evaluated. A detailed microstructural analysis was performed on each heat, at different levels, involving SEM and TEM examinations at high magnification on etched samples, to reveal the phases present at grain boundaries. Methodologies were developed to quantify the grain boundary coverage (length of precipitates at grain boundary divided by the total grain boundary length), and to study the distribution in size (equivalent diameter, surface, shape factor) of the grain boundary precipitates, and applied to the studied materials. Elemental chemical analysis of the precipitates was also conducted by Energy Dispersive X-ray spectrometry. The performance of the different alloys with respect to HISC resistance is discussed on the basis of the plastic elongation obtained in the SSRT tests under cathodic polarization, the microstructural features and the microstructural criteria given in the API 6A CRA standard.
|
|
| 10. |
- Trillo, E., et al.
(författare)
-
Assessment of the hydrogen induced stress cracking resistance of precipitation hardened nickel-based alloys using the slow strain rate tensile test method - Experimental parameters and related issues
- 2019
-
Ingår i: NACE - International Corrosion Conference SeriesVolume 2019-March, 2019, Nashville; United States; 24 March 2019 through 28 March 2019. - : National Assoc. of Corrosion Engineers International.
-
Konferensbidrag (refereegranskat)abstract
- Within the framework of a Joint Industrial Project (JIP) sponsored by several petroleum companies, the behavior of several Precipitation Hardened (PH) Ni-based alloys with respect to Hydrogen Induced Stress Cracking (HISC) resistance was studied using the Slow Strain Rate Tensile (SSRT) test method under hydrogen charging conditions. The experimental conditions included a 0.5M sulfuric acid solution at 5 mA/cm2 and at 40°C at a strain rate of 10-6 sec-1. A round robin was performed that highlighted the need to measure the effective strain rate of the specimen during the elastic part of the SSRT test, the cell configuration, the current density, the gas cap composition, were all studied to determine the effects on the results. Once the test conditions had been optimized, the study of different industrial heats was carried out on specimens sampled in three locations, 120 degrees apart and at mid radius. It was found that sampling different areas could lead to changes in the test results, resulting mainly from microstructural variances at different locations of the bar. The results generated in this program could then be studied by relating plastic elongation obtained under CP as well as cracking mode and microstructure compliance with the API 6A CRA standard.
|
|
