scholarly journals Closure times of neurocranial sutures and synchondroses in Persian compared to Domestic Shorthair cats

2022 ◽  
Vol 12 (1) ◽  
Author(s):  
Martin J. Schmidt ◽  
Daniela Farke ◽  
Carsten Staszyk ◽  
Antonia Lang ◽  
Kathrin Büttner ◽  
...  
Keyword(s):  
Selective Breeding ◽  
Spontaneous Mutation ◽  
Time Dependent ◽  
Micro Computed Tomography ◽  
Global Effect ◽  
Skull Morphology ◽  
Skull Development ◽  
Suture Closure ◽  
Effect Of Age ◽  
Formalin Fixed

AbstractHuman-directed selective breeding has modified the phenotype of the modern Persian cat towards an extreme brachycephalic phenotype (‘peke-face’ Persian), which originates from a spontaneous mutation that first appeared in the 1950s in traditional Persian types. It was suggested that the peke-face phenotype results from pathologic skull development and might represent a craniosynostosis of the coronal sutures. We followed this hypothesis and investigated the time dependent status of the neurocranial sutures and synchondroses in an ontogenetic series of doll-faced and peke-faced Persian cats compared to Domestic Shorthair cats (DSHs). Cranial suture closure was assessed by examining an ontogenetic series of formalin-fixed head specimens (n = 55) and dry skulls (n = 32) using micro-computed tomography. Sagittal, metopic, coronal and lambdoid sutures as well as intersphenoidal, spheno-occipital and spheno-ethmoid synchondroses were examined. Logistic regression analysis was performed to test the global effect of age on suture closure within a group of peke-face Persians, doll-face Persians and DSHs and the 50% probability of having a closed suture was calculated and compared between groups. Age was a perfect predictor for the condition of the coronal sutures in peke-face Persians. Coronal sutures were found to be closed at 0–0.3 months. In doll-face and DSHs, coronal sutures were open throughout the lifetime with the exception of a few very old cats. Results of this study confirmed a coronal craniosynostosis that likely causes the extreme brachycephalic skull morphology in the peke-face Persian.

scholarly journals Immunofluorescence-guided segmentation of three-dimensional features in micro-computed tomography datasets of human lung tissue

2021 ◽  
Vol 8 (11) ◽  
Author(s):  
Matthew J. Lawson ◽  
Orestis L. Katsamenis ◽  
David Chatelet ◽  
Aiman Alzetani ◽  
Oliver Larkin ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Lung Tissue ◽  
Human Lung ◽  
Three Dimensional ◽  
Micro Computed Tomography ◽  
3D Segmentation ◽  
Human Lung Tissue ◽  
Formalin Fixed Paraffin ◽  
Formalin Fixed Paraffin Embedded ◽  
Formalin Fixed

Micro-computed tomography (µCT) provides non-destructive three-dimensional (3D) imaging of soft tissue microstructures. Specific features in µCT images can be identified using correlated two-dimensional (2D) histology images allowing manual segmentation. However, this is very time-consuming and requires specialist knowledge of the tissue and imaging modalities involved. Using a custom-designed µCT system optimized for imaging unstained formalin-fixed paraffin-embedded soft tissues, we imaged human lung tissue at isotropic voxel sizes less than 10 µm. Tissue sections were stained with haematoxylin and eosin or cytokeratin 18 in columnar airway epithelial cells using immunofluorescence (IF), as an exemplar of this workflow. Novel utilization of tissue autofluorescence allowed automatic alignment of 2D microscopy images to the 3D µCT data using scripted co-registration and automated image warping algorithms. Warped IF images, which were accurately aligned with the µCT datasets, allowed 3D segmentation of immunoreactive tissue microstructures in the human lung. Blood vessels were segmented semi-automatically using the co-registered µCT datasets. Correlating 2D IF and 3D µCT data enables accurate identification, localization and segmentation of features in fixed soft lung tissue. Our novel correlative imaging workflow provides faster and more automated 3D segmentation of µCT datasets. This is applicable to the huge range of formalin-fixed paraffin-embedded tissues held in biobanks and archives.

197A: THE DEVELOPMENT OF NOVEL MICRO-COMPUTED TOMOGRAPHY SNAKE ALGORITHM TO DETERMINE TIME COURSE OF POSTERIOR FRONTAL SUTURE CLOSURE IN MICE

2010 ◽  
Vol 125 (Supplement) ◽  
pp. 129
Author(s):  
C Hermann ◽  
R Olivares-Navarrete ◽  
M Richards ◽  
RE Guldberg ◽  
O Skrinjar ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Time Course ◽  
Micro Computed Tomography ◽  
Suture Closure ◽  
Snake Algorithm

scholarly journals Time-Dependent Anti-Demineralization Effect of Silver Diamine Fluoride

Children ◽  
2020 ◽  
Vol 7 (12) ◽  
pp. 251
Author(s):  
Ji-Hye Ahn ◽  
Ji-Woong Kim ◽  
Young-Mi Yoon ◽  
Nan-Young Lee ◽  
Sang-Ho Lee ◽  
...  
Keyword(s):  
Surface Morphology ◽  
Surface Density ◽  
Enamel Surface ◽  
Time Dependent ◽  
Fluoride Varnish ◽  
Control Group ◽  
Micro Ct ◽  
Micro Computed Tomography ◽  
Silver Diamine Fluoride ◽  
Demineralized Enamel

This study compared the demineralization resistance of teeth treated with silver diamine fluoride (SDF) to that treated with fluoride varnish. A total of 105 healthy bovine incisors were divided into control, fluoride varnish, and SDF groups. The enamel surface density change was then measured by micro-computed tomography (micro-CT) at three depths. The demineralized zone volume was measured on 3D micro-CT images to evaluate the total demineralization rate. The enamel surface morphology was assessed by scanning electron microscope. The enamel density had continuously decreased while demineralization increased in the control and fluoride varnish groups. The enamel density had increased in the SDF group till the 7th day of demineralization treatment and decreased thereafter. However, the decrease in the SDF group was less severe than that in the other groups (p < 0.05). The demineralized enamel volume had increased through treatment and was the highest in the control group, followed by the fluoride varnish and SDF group. The enamel surface morphology was the roughest and most irregular in the control group, followed by the fluoride varnish group and SDF groups.

Faecal nematode egg counts in lactating ewes from Romney flocks selectively bred for divergence in lamb faecal egg count

1998 ◽  
Vol 67 (2) ◽  
pp. 283-288 ◽  
Author(s):  
C. A. Morris ◽  
S. A. Bisset ◽  
A. Vlassoff ◽  
C. J. West ◽  
M. Wheeler
Keyword(s):  
Selective Breeding ◽  
Genetic Effects ◽  
Grazing Management ◽  
Phenotypic Correlation ◽  
Correlated Response ◽  
Genetic Changes ◽  
Faecal Samples ◽  
Faecal Egg Count ◽  
Parasite Infections ◽  
Effect Of Age

AbstractFaecal nematode egg counts (FECs) were examined in lactating ewes from divergent flocks of Romney sheep which had been selectively bred from 1979 to 1996 for or against FEC in 4 to 7 month old lambs. Faecal samples were obtained from the ewes while under normal grazing management, 1 to 2 months after lambing in spring for each of 6 years between 1987 and 1996 (no. = 785 records; 298 animals). Analyses were carried out on loge (FEC + 100)–transformed data using animal-model maximum likelihood procedures, accounting for repeated records on ewes, within and between lactations. An examination of non-genetic effects indicated that there was no significant effect of age class of ewe on FEC but ewes which gave birth to single lambs had significantly lower post-parturient FECs than those bearing twins (back-transformed means of 184 v. 276 egg per g, respectively; P < 0·001). In relation to genetic effects, post-parturient FECs were significantly lower in ewes from the flock bred for low lamb-FEC than in their counterparts from the flock bred for high lamb-FEC, with ewes from the most recent birth years (1991 to 1994) showing a nine-fold difference (back-transformed means of 33 and 305 eggs per g faeces respectively; P < 0·001). This was equivalent to 69% of the divergence observed between loge (FEC + 100) in their lambs in the same years. Heritability and repeatability estimates for loge (FEC + 100) in ewes were 0·37 (s.e. 0·06) and 0·46 (s.e. 0·03) respectively. Genetic correlation estimates between a ewe's post-parturient loge (FEC + 200) and her loge (FEC + 100) as a lamb, based on analysis of (co)variance or realized responses, were 0·70 or 0·58 respectively. The phenotypic correlation between a ewe's loge (FEC + 100) and that of her lamb(s) in the same lactation was 0·29 (s.e. 0·06) (P < 0·001). From the results it is clear that substantial genetic changes in post-parturient FECs of breeding ewes can be induced through a correlated response to selective breeding for or against reduced FEC in lambs. This may have important implications for the epidemiology of nematode parasite infections in spring-born lambs, a possibility which is currently being investigated.

scholarly journals A large and unusually colored new snake species of the genusTantilla(Squamata; Colubridae) from the Peruvian Andes

PeerJ ◽  
2016 ◽  
Vol 4 ◽  
pp. e2767
Author(s):  
Claudia Koch ◽  
Pablo J. Venegas
Keyword(s):  
Computed Tomography ◽  
New Species ◽  
Color Pattern ◽  
Dry Forest ◽  
Micro Computed Tomography ◽  
Skull Morphology ◽  
Peruvian Andes ◽  
The Third ◽  
Computed Tomography Images ◽  
Human Interventions

A new colubrid species of the genusTantillafrom the dry forest of the northern Peruvian Andes is described on the basis of two specimens, which exhibit a conspicuous sexual dimorphism.Tantilla tjiasmantoisp. nov. represents the third species of the genus in Peru. The new species is easily distinguished from its congeners by the combination of scalation characteristics and the unusual transversely-banded color pattern on the dorsum. A detailed description of the skull morphology of the new species is given based on micro-computed tomography images. The habitat of this new species is gravely threatened due to human interventions. Conservation efforts are urgently needed in the inter-Andean valley of the Maranon River.

scholarly journals Beyond the carapace: skull shape variation and morphological systematics of long-nosed armadillos (genus Dasypus)

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3650 ◽  
Author(s):  
Lionel Hautier ◽  
Guillaume Billet ◽  
Benoit de Thoisy ◽  
Frédéric Delsuc
Keyword(s):  
Morphological Variation ◽  
Distinct Species ◽  
Morphological Characters ◽  
Molecular Data ◽  
Shape Variation ◽  
Micro Computed Tomography ◽  
Dasypus Novemcinctus ◽  
Skull Morphology ◽  
Geometric Morphometric ◽  
Skull Shape

Background The systematics of long-nosed armadillos (genus Dasypus) has been mainly based on a handful of external morphological characters and classical measurements. Here, we studied the pattern of morphological variation in the skull of long-nosed armadillos species, with a focus on the systematics of the widely distributed nine-banded armadillo (Dasypus novemcinctus). Methods We present the first exhaustive 3D comparison of the skull morphology within the genus Dasypus, based on micro-computed tomography. We used geometric morphometric approaches to explore the patterns of the intra- and interspecific morphological variation of the skull with regard to several factors such as taxonomy, geography, allometry, and sexual dimorphism. Results We show that the shape and size of the skull vary greatly among Dasypus species, with Dasypus pilosus representing a clear outlier compared to other long-nosed armadillos. The study of the cranial intraspecific variation in Dasypus novemcinctus evidences clear links to the geographic distribution and argues in favor of a revision of past taxonomic delimitations. Our detailed morphometric comparisons detected previously overlooked morphotypes of nine-banded armadillos, especially a very distinctive unit restricted to the Guiana Shield. Discussion As our results are congruent with recent molecular data and analyses of the structure of paranasal sinuses, we propose that Dasypus novemcinctus should be regarded either as a polytypic species (with three to four subspecies) or as a complex of several distinct species.

Ultrastructural Localization of Acid Mucosubstance in Skeletal Muscle

1967 ◽  
Vol 25 ◽  
pp. 52-53 ◽  
Author(s):  
William J. Dougherty ◽  
Samuel S. Spicer
Keyword(s):  
Striated Muscle ◽  
Divalent Cations ◽  
Ultrastructural Localization ◽  
Major Elements ◽  
Frozen Sections ◽  
Thorium Dioxide ◽  
Iron Solution ◽  
Coupling System ◽  
Psoas Muscles ◽  
Formalin Fixed

In recent years, considerable attention has focused on the morphological nature of the excitation-contraction coupling system of striated muscle. Since the study of Porter and Palade, it has become evident that the sarcoplastic reticulum (SR) and transverse tubules constitute the major elements of this system. The problem still exists, however, of determining the mechamisms by which the signal to interdigitate is presented to the thick and thin myofilaments. This problem appears to center on the movement of Ca++ions between myofilaments and SR. Recently, Philpott and Goldstein reported acid mucosubstance associated with the SR of fish branchial muscle using the colloidal thorium dioxide technique, and suggested that this material may serve to bind or release divalent cations such as Ca++. In the present study, Hale's iron solution adapted to electron microscopy was applied to formalin-fixed myofibrils isolated from glycerol-extracted rabbit psoas muscles and to frozen sections of formalin-fixed rat psoas muscles.

Sign in / Sign up

Export Citation Format

Share Document