scholarly journals Late Ediacaran life on land: desiccated microbial mats and large biofilm streamers

2021 ◽  
Vol 288 (1962) ◽  
Author(s):  
S. McMahon ◽  
J. J. Matthews ◽  
A. Brasier ◽  
J. Still
Keyword(s):  
Soft Tissue ◽  
Microbial Mats ◽  
Transformational Change ◽  
Depositional Environments ◽  
Tissue Preservation ◽  
Microbial Ecosystems ◽  
The Earth ◽  
Terrestrial Environments ◽  
Mode Of Life ◽  
A Current

The Ediacaran period witnessed transformational change across the Earth–life system, but life on land during this interval is poorly understood. Non-marine/transitional Ediacaran sediments preserve a variety of probable microbially induced sedimentary structures and fossil matgrounds, and the ecology, biogeochemistry and sedimentological impacts of the organisms responsible are now ripe for investigation. Here, we report well-preserved fossils from emergent siliciclastic depositional environments in the Ediacaran of Newfoundland, Canada. These include exquisite, mouldically preserved microbial mats with desiccation cracks and flip-overs, abundant Arumberia -type fossils and, most notably, assemblages of centimetre-to-metre-scale, subparallel, branching, overlapping, gently curving ribbon-like features preserved by aluminosilicate and phosphate minerals, with associated filamentous microfossils. We present morphological, petrographic and taphonomic evidence that the ribbons are best interpreted as fossilized current-induced biofilm streamers, the earliest record of an important mode of life (macroscopic streamer formation) for terrestrial microbial ecosystems today. Their presence shows that late Ediacaran terrestrial environments could produce substantial biomass, and supports recent interpretations of Arumberia as a current-influenced microbial mat fossil, which we here suggest existed on a ‘streamer–arumberiamorph spectrum’. Finally, the absence of classic Ediacaran macrobiota from these rocks despite evidently favourable conditions for soft tissue preservation upholds the consensus that those organisms were exclusively marine.

SEDIMENT COMPOSITION OF BURGESS SHALE TYPE LAGERSTÄTTEN: IMPLICATIONS FOR SOFT-TISSUE PRESERVATION

2016 ◽  
Author(s):  
Ross P. Anderson ◽  
◽  
Nicholas J. Tosca ◽  
Robert R. Gaines ◽  
Derek E.G. Briggs
Keyword(s):  
Soft Tissue ◽  
Tissue Preservation ◽  
Burgess Shale ◽  
Sediment Composition ◽  
Soft Tissue Preservation

scholarly journals Soft tissue and cellular preservation in vertebrate skeletal elements from the Cretaceous to the present

2007 ◽  
Vol 274 (1607) ◽  
pp. 183-197 ◽  
Author(s):  
Mary Higby Schweitzer ◽  
Jennifer L Wittmeyer ◽  
John R Horner
Keyword(s):  
Soft Tissue ◽  
Soft Tissues ◽  
Bone Matrix ◽  
Molecular Data ◽  
Depositional Environments ◽  
Medullary Bone ◽  
Geological Time ◽  
Fossil Bone ◽  
Alternative Hypotheses ◽  
Molecular Components

Soft tissues and cell-like microstructures derived from skeletal elements of a well-preserved Tyrannosaurus rex (MOR 1125) were represented by four components in fragments of demineralized cortical and/or medullary bone: flexible and fibrous bone matrix; transparent, hollow and pliable blood vessels; intravascular material, including in some cases, structures morphologically reminiscent of vertebrate red blood cells; and osteocytes with intracellular contents and flexible filipodia. The present study attempts to trace the occurrence of these four components in bone from specimens spanning multiple geological time periods and varied depositional environments. At least three of the four components persist in some skeletal elements of specimens dating to the Campanian. Fibrous bone matrix is more altered over time in morphology and less likely to persist than vessels and/or osteocytes. Vessels vary greatly in preservation, even within the same specimen, with some regions retaining pliability and other regions almost crystalline. Osteocytes also vary, with some retaining long filipodia and transparency, while others present with short and stubby filipodia and deeply pigmented nuclei, or are pigmented throughout with no nucleus visible. Alternative hypotheses are considered to explain the origin/source of observed materials. Finally, a two-part mechanism, involving first cross-linking of molecular components and subsequent mineralization, is proposed to explain the surprising presence of still -soft elements in fossil bone. These results suggest that present models of fossilization processes may be incomplete and that soft tissue elements may be more commonly preserved, even in older specimens, than previously thought. Additionally, in many cases, osteocytes with defined nuclei are preserved, and may represent an important source for informative molecular data.

scholarly journals Checklist and Scoring System for the Assessment of Soft Tissue Preservation in CT Examinations of Human Mummies: Application to the Tyrolean Iceman

2017 ◽  
Vol 189 (12) ◽  
pp. 1152-1160
Author(s):  
Stephanie Panzer ◽  
Patrizia Pernter ◽  
Dario Piombino-Mascali ◽  
Rimantas Jankauskas ◽  
Stephanie Zesch ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Scoring System ◽  
Soft Tissues ◽  
Whole Body ◽  
Slice Thickness ◽  
Tissue Preservation ◽  
Soft Tissue Preservation ◽  
Whole Body Ct ◽  
Organ Systems ◽  
Tyrolean Iceman

Purpose Soft tissues make a skeleton into a mummy and they allow for a diagnosis beyond osteology. Following the approach of structured reporting in clinical radiology, a recently developed checklist was used to evaluate the soft tissue preservation status of the Tyrolean Iceman using computed tomography (CT). The purpose of this study was to apply the “Checklist and Scoring System for the Assessment of Soft Tissue Preservation in CT Examinations of Human Mummies” to the Tyrolean Iceman, and to compare the Iceman’s soft tissue preservation score to the scores calculated for other mummies. Materials and Methods A whole-body (CT) (SOMATOM Definition Flash, Siemens, Forchheim, Germany) consisting of five scans, performed in January 2013 in the Department of Radiodiagnostics, Central Hospital, Bolzano, was used (slice thickness 0.6 mm; kilovolt ranging from 80 to 140). For standardized evaluation the “CT Checklist and Scoring System for the Assessment of Soft Tissue Preservation in Human Mummies” was used. Results All checkpoints under category “A. Soft Tissues of Head and Musculoskeletal System” and more than half in category “B. Organs and Organ Systems” were observed. The scoring system accounted for a total score of 153 (out of 200). The comparison of the scores between the Iceman and three mummy collections from Vilnius, Lithuania, and Palermo, Sicily, as well as one Egyptian mummy resulted in overall higher soft tissue preservation scores for the Iceman. Conclusion Application of the checklist allowed for standardized assessment and documentation of the Iceman’s soft tissue preservation status. The scoring system allowed for a quantitative comparison between the Iceman and other mummies. The Iceman showed remarkable soft tissue preservation. Key Points  Citation Format

scholarly journals Long-Term Outcomes of the Minimally Invasive Ponto Surgery vs. Linear Incision Technique With Soft Tissue Preservation for Installation of Percutaneous Bone Conduction Devices

2021 ◽  
Vol 12 ◽  
Author(s):  
Ruben M. Strijbos ◽  
Louise V. Straatman ◽  
Tim G. A. Calon ◽  
Martin L. Johansson ◽  
Arthur J. G. de Bruijn ◽  
...  
Keyword(s):  
Quality Of Life ◽  
Soft Tissue ◽  
Bone Conduction ◽  
Tissue Preservation ◽  
Implant Stability ◽  
Implant Stability Quotient ◽  
Incision Technique

Objective: Comparing the surgical outcomes of the Minimally Invasive Ponto Surgery (MIPS) technique with the linear incision technique with soft tissue preservation (LITT-P) for bone conduction devices after a follow-up of 22 months.Methods: In this multicenter randomized controlled trial, there was the inclusion of 64 adult patients eligible for unilateral surgery. There was 1:1 randomization to the MIPS (test) or the LITT-P (control) group. The primary outcome was an (adverse) soft tissue reaction. Secondary outcomes were pain, loss of sensibility, soft tissue height/overgrowth, skin sagging, implant loss, Implant Stability Quotient measurements, cosmetic scores, and quality of life questionnaires.Results: Sixty-three subjects were analyzed in the intention-to-treat population. No differences were found in the presence of (adverse) soft tissue reactions during complete follow-up. Also, there were no differences in pain, wound dehiscence, skin level, soft tissue overgrowth, and overall quality of life. Loss of sensibility (until 3-month post-surgery), cosmetic scores, and skin sagging outcomes were better in the MIPS group. The Implant Stability Quotient was higher after the LITT-P for different abutment lengths at various points of follow-up. Implant extrusion was nonsignificantly higher after the MIPS (15.2%) compared with LITT-P (3.3%).Conclusion: The long-term results show favorable outcomes for both techniques. The MIPS is a promising technique with some benefits over the LITT-P. Concerns regarding nonsignificantly higher implant loss may be overcome with future developments and research.Clinical Trial Registration:www.ClinicalTrials.gov, identifier: NCT02438618.

scholarly journals Confirmation of ovarian follicles in an enantiornithine (Aves) from the Jehol biota using soft tissue analyses

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Alida M. Bailleul ◽  
Jingmai O’Connor ◽  
Zhiheng Li ◽  
Qian Wu ◽  
Tao Zhao ◽  
...  
Keyword(s):  
High Resolution ◽  
Soft Tissue ◽  
Smooth Muscles ◽  
Ovarian Follicles ◽  
Tissue Preservation ◽  
Jehol Biota ◽  
Avian Evolution ◽  
The Right ◽  
Original Interpretation ◽  
Contractile Structure

AbstractThe remains of ovarian follicles reported in nine specimens of basal birds represents one of the most remarkable examples of soft-tissue preservation in the Early Cretaceous Jehol Biota. This discovery was immediately contested and the structures alternatively interpreted as ingested seeds. Fragments of the purported follicles preserved in an enantiornithine (STM10-12) were extracted and subjected to multiple high-resolution analyses. The structures in STM10-12 possess the histological and histochemical characteristics of smooth muscles fibers intertwined together with collagen fibers, resembling the contractile structure in the perifollicular membrane (PFM) of living birds. Fossilized blood vessels, very abundant in extant PFMs, are also preserved. Energy Dispersive Spectroscopy shows the preserved tissues primarily underwent alumino-silicification, with minor mineralization via iron oxides. No evidence of plant tissue was found. These results confirm the original interpretation as follicles within the left ovary, supporting the interpretation that the right ovary was functionally lost early in avian evolution.

scholarly journals A Systematic Approach to the Application of Soft Tissue Histopathology in Paleopathology

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Christina Grove ◽  
Oliver Peschel ◽  
Andreas G. Nerlich
Keyword(s):  
Soft Tissue ◽  
Connective Tissue ◽  
Time Interval ◽  
Tissue Preservation ◽  
Fat Tissue ◽  
Short Term ◽  
Internal Organs ◽  
Time Intervals ◽  
Pathological Conditions ◽  
Desert Areas

The application of histology to soft tissue remains offers an important technique to obtain diagnostically important information on various physiological and pathological conditions in paleopathology. In a series of 29 cases with mummified tissue ranging between 16 months and c. 5.200 years of postmortem time interval, we systematically investigated paleohistology and the preservation of various tissues. We established a reproducible histological ranking system for the evaluation of mummified tissue preservation. The application of this scheme to the series showed good tissue preservation of tissues with high connective tissue content but also fat tissue and connective tissue rich organs, such as lung tissue, while most other internal organs were less well preserved despite highly different postmortem time intervals. There are some organs with only poor conservation even in short term periods such as the kidneys and CNS. Artificial mummification does not provide better conservation than naturally mummified tissues; “cold” mummies may be much better conserved than those from desert areas. The identification of specific pathologies underlines the potential power of paleohistology.

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