Live imaging of stem cell and progeny behaviour in physiological hair-follicle regeneration

Tissue development and regeneration depend on cell-cell interactions and signals that target stem cells and their immediate progeny. However, the cellular behaviours that lead to a properly regenerated tissue are not well understood. Using a new, non-invasive, intravital two-photon imaging approach we study physiological hair-follicle regeneration over time in live mice. By these means we have monitored the behaviour of epithelial stem cells and their progeny during physiological hair regeneration and addressed how the mesenchyme influences their behaviour. Consistent with earlier studies, stem cells are quiescent during the initial stages of hair regeneration, whereas the progeny are more actively dividing. Moreover, stem cell progeny divisions are spatially organized within follicles. In addition to cell divisions, coordinated cell movements of the progeny allow the rapid expansion of the hair follicle. Finally, we show the requirement of the mesenchyme for hair regeneration through targeted cell ablation and long-term tracking of live hair follicles. Thus, we have established an in vivo approach that has led to the direct observation of cellular mechanisms of growth regulation within the hair follicle and that has enabled us to precisely investigate functional requirements of hair-follicle components during the process of physiological regeneration. © 2012 Macmillan Publishers Limited. All rights reserved

Ezrin Is Highly Expressed in Early Thymocytes, but Dispensable for T Cell Development in Mice

Ezrin/radixin/moesin (ERM) proteins are highly homologous proteins that function to link cargo molecules to the actin cytoskeleton. Ezrin and moesin are both expressed in mature lymphocytes, where they play overlapping roles in cell signaling and polarity, but their role in lymphoid development has not been explored.We characterized ERM protein expression in lymphoid tissues and analyzed the requirement for ezrin expression in lymphoid development. In wildtype mice, we found that most cells in the spleen and thymus express both ezrin and moesin, but little radixin. ERM protein expression in the thymus was differentially regulated, such that ezrin expression was highest in immature thymocytes and diminished during T cell development. In contrast, moesin expression was low in early thymocytes and upregulated during T cell development. Mice bearing a germline deletion of ezrin exhibited profound defects in the size and cellularity of the spleen and thymus, abnormal thymic architecture, diminished hematopoiesis, and increased proportions of granulocytic precursors. Further analysis using fetal liver chimeras and thymic transplants showed that ezrin expression is dispensable in hematopoietic and stromal lineages, and that most of the defects in lymphoid development in ezrin(-/-) mice likely arise as a consequence of nutritional stress.We conclude that despite high expression in lymphoid precursor cells, ezrin is dispensable for lymphoid development, most likely due to redundancy with moesin

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Visualization of microcrack anisotropy in granite affected by a fault zone, using confocal laser scanning microscope

Brittle deformation in granite can generate a fracture system with different patterns. Detailed fracture analyses at both macroscopic and microscopic scales, together with physical property data from a drill-core, are used to classify the effects of reverse fault deformation in four domains: (1) undeformed granite, (2) fractured granite with cataclastic seams, (3) fractured granite from the damage zone, and (4) foliated cataclasite from the core of the fault. Intact samples from two orthogonal directions, horizontal (H) and vertical (V), from the four domains indicate a developing fracture anisotropy toward the fault, which is highly developed in the damage zone. As a specific illustration of this phenomenon, resin impregnation, using a confocal laser scanning microscope (CLSM) technique is applied to visualize the fracture anisotropy developed in the Toki Granite, Japan. As a result, microcrack networks have been observed to develop in H sections and elongate open cracks in V sections, suggesting that flow pathways can be determined by deformation

Visualization of microcrack anisotropy in granite affected by afault zone, using confocal laser scanning microscope

Brittle deformation in granite can generate a fracture system with different patterns. Detailed fracture analyses at both macroscopic and microscopic scales, together with physical property data from a drill-core, are used to classify the effects of reverse fault deformation in four domains: (1) undeformed granite, (2) fractured granite with cataclastic seams, (3) fractured granite from the damage zone, and (4) foliated cataclasite from the core of the fault. Intact samples from two orthogonal directions, horizontal (H) and vertical (V), from the four domains indicate a developing fracture anisotropy toward the fault, which is highly developed in the damage zone. As a specific illustration of this phenomenon, resin impregnation, using a confocal laser scanning microscope (CLSM) technique is applied to visualize the fracture anisotropy developed in the Toki Granite, Japan. As a result, microcrack networks have been observed to develop in H sections and elongate open cracks in V sections, suggesting that flow pathways can be determined by deformation

Visualization of microcrack anisotropy in granite affected by a fault zone, using confocal laser scanning microscope

Brittle deformation in granite can generate a fracture system with different patterns. Detailed fracture analyses at both macroscopic and microscopic scales, together with physical property data from a drill-core, are used to classify the effects of reverse fault deformation in four domains: (1) undeformed granite, (2) fractured granite with cataclastic seams, (3) fractured granite from the damage zone, and (4) foliated cataclasite from the core of the fault. Intact samples from two orthogonal directions, horizontal (H) and vertical (V), from the four domains indicate a developing fracture anisotropy toward the fault, which is highly developed in the damage zone. As a specific illustration of this phenomenon, resin impregnation, using a confocal laser scanning microscope (CLSM) technique is applied to visualize the fracture anisotropy developed in the Toki Granite, Japan. As a result, microcrack networks have been observed to develop in H sections and elongate open cracks in V sections, suggesting that flow pathways can be determined by deformation

OCLC Search Key Usage Patterns in a Large Research Library

Many libraries use the OCLC Online Union Catalog and Shared Cataloging Subsystem to perform various library functions, such as acquisitions and cataloging of library materials. As an initial part of the operations,users must search and retrieve a bibliographic record for the desired item from the large OC LC database. Various types of derived search keys are available for retrieval. This study of actual search keysentered by users of the OCLC online system was conducted to determine the types of search keys users prefer for performing various library operations and to find out whether the preferred search keys are effective

Issues in Distribution of Grey Literature : Experience of the Japan Documentation Center (JDC)

The focus of this paper is to present some issues in grey literature, its dissemination, its place in the collection, grey literature in electronic formats, and difficulty in dealing with languages of publication. Those issues are presented from the past five years of the author's experiences in establishing and developing the Japan Documentation Center. The Center collects, processes and disseminates Japanese policy related grey literature in the areas of politics, economics, business and industry, the environment, and national defense. The discussion, research results, and suggestions follow each. The first issue is on grey literature and its users. Users of such information like Japanese policy related literature are not necessarily scholars and specialists in Japanese studies. They encompass lawyers, economists, legislators, scientists and many people of other disciplines who must deal with Japan in their own special field. Some are not even regular library users. To disseminate the information on the functions of the Center is a great challenge because one cannot pin-point target groups such as the Association for Asian Studies and the Council on East Asian Libraries. The second issue is the place of grey literature in the collection development policy in relation to other Japanese materials in a collection. In the recent budgetary crunch in many libraries, the criterion for collection development are reviewed and tightened in general to its core materials of research value in the long-term perspectives of the library, whereas the value of grey literature is for its timeliness and urgent need for practical purposes but not necessarily for its historical value. How the library managers justify the efforts and costs needed for collecting grey literature is interesting. The third is the development of electronic information distribution and coping with it. Besides the copyright issue which the author does not discuss here, establishing the good practice in handling increasing number of electronically distributed grey literature in relation to paper copies should be thought of. The fourth is the language of the grey literature. This issue relates to all the above issues; users, collection policies, and electronic distribution of grey literature. In the case of the JDC in which the major portion of literature is in Japanese, how to reduce the difficulties of users dealing with Japanese is another serious matter for some users. The author discusses each issue area further in detail, with analysis in some cases, and brings some findings or ideas.Includes : Conference preprintXAInternationa

International Cooperation in Dissemination of Grey Literature using the INTERNET: A Protocol

The demand for the grey literature issued in Japan is strong and has been growing. However, the most problematic aspect for the unpublished information in Japan has been, as the description "difficult-to-obtain information" indicates, its timely acquisition. The Japan Documentation Center, established in the Library of Congress as a part of the solution to this problem, collects and disseminates Japanese grey literature in the areas of policy research, draft legislation, business and economics, environment, and national defense. The Center's Tokyo facility staff actually goes to collect those documents on foot. We prepare the bibliographic data sheet with English abstract for each of those documents. Those documents are then scanned and stored in optical disks. The bibliographic information contained on the datasheets is available on the INTERNET. All the communications between users and the Center are made electronically and finally the printed documents are delivered to the users. Obstacles of distance and time are thus minimized. The Center was established in the Library of Congress, with a large grant of the Japan Foundation Center for Global Partnership. It should also be noted that the Japan National Diet Library, which is the largest collector of Japan's grey literature, cooperates and makes special efforts in supplying available documents to the Center. The Japan Documentation Center's scale is small and its focus is narrow. However, this is one of the ideal ways for effective acquisition and timely dissemination of the specific types of information which would otherwise be difficult to manage. It is accomplished only through the combination of experts' knowledge and experience, funding, international cooperation, and most importantly the capability to utilize electronic transmission of data.Includes : Conference preprint, Pratt student commentaryXAInternationa