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Routine and Special Techniques in Toxicologic Pathology
Published in Pritam S. Sahota, James A. Popp, Jerry F. Hardisty, Chirukandath Gopinath, Page R. Bouchard, Toxicologic Pathology, 2018
Daniel J. Patrick, Matthew L. Renninger, Peter C. Mann
Stereology refers to the statistical derivation of three-dimensional data based on measurements of two-dimensional tissue sections (Weibel et al. 1966). Stereologic assessments require planning prior to necropsy since the entire organ of interest must be available for sampling. Traditional stereologic methods required assumptions about the size and shape of the particles being measured, which was considered a biased method. The benefits of current stereologic methods include unbiased random sampling and increased statistical accuracy, sensitivity, and precision (reproducibility). Various stereologic methods in use today rely only on sampling designs and allow for the counting and sizing of particles without the introduction of bias owing to assumptions on size and shape. These methods are often referred to as “design-based” or “unbiased” stereologic methods (R. W. Boyce et al. 2010). Design-based stereologic methods are the most sensitive and accurate methods to obtain quantitative data about tissues and are preferred over two-dimensional morphometric methods when critical decisions need to be made in the drug development or risk assessment process. Today, stereologic methods are becoming much more efficient and practical because of advances in stereologic theory, stereologic software, sampling techniques, and imaging devices including automated WSI. One of the most common applications of stereologic methods in nonclinical safety assessments is in neurotoxicity evaluations.
Mechanical testing
Published in C M Langton, C F Njeh, The Physical Measurement of Bone, 2016
Christopher F Njeh, Patrick H Nicholson, Jae-Young Rho
Researchers including Brown and Ferguson [35] have tried to link the stress pattern to the actual orientation of trabeculae. This has been thanks to advanced stereology, digital analysis algorithms and refined imaging processes. Pugh et al [46], Townsend et al [91] and Hodgskinson and Currey [98, 185] have attempted to correlate the architectural properties (anisotropy, fabric and connectivity) and morphologic measures (trabecular plate thickness and trabecular plate separation) to the structural level mechanical properties of cancellous bone. The problem of multi-collinearity makes it difficult to establish the true underlying pattern of relationships. However, there is convincing evidence for a significant role for fabric, independent of apparent density, in determining mechanical properties [98, 185].
Design-Based Stereology in Brain Aging Research
Published in David R. Riddle, Brain Aging, 2007
Christoph Schmitz, Patrick R. Hof
Originally, design-based stereology was described as a set of methods that provide a three-dimensional interpretation of structures based on observations made on two-dimensional sections [1]. However, in the current use of design-based stereology, many methods make use of three-dimensional sections. The term “design-based” indicates that the methods and the sampling schemes that define the newer methods in stereology are “designed,” that is, defined a priori, in such a manner that one need not take into consideration the size, shape, spatial orientation, and spatial distribution of the cells to be investigated [2]. Eliminating the need for information about the geometry of the cells under investigation results in more robust data because potential sources of systematic errors in the calculations are eliminated [2–4].
Potential Effects of Stem Cells Derived from the Peripheral Nerve and Adipose Tissue after the Nerve Crush Injury in Control and Obese Rats
Published in Journal of Investigative Surgery, 2022
Elif Kayhan Kustepe, Berrin Zuhal Altunkaynak, Işınsu Alkan, Elfide Gizem Kivrak, Alişan Yildiran, Stefano Geuna
Light microscopic analysis of the semi-thin sections was performed in a computer-aided stereology workstation (Stereoinvestigator 9.0, Micro-Brield-Field; Colchester, USA). The fractionator method was used for myelinated axon counting. Myelinated axons were counted by using an unbiased counting frame in each sampled area. For this, 60 μm × 60 μm step size and 25 μm × 25 μm neutral counting frames in a systematic-random manner were used. Thus, according to the fractionator method, an area of 625 μm2 was sampled from each 3600 μm2 area [13,14]. Rules on unbiased counting frame were considered to account myelinated axons, measure axonal diameter and myelin thickness. According to the rules; the unbiased counting frame has four boundaries which have two inclusion lines and two exclusion lines with extension. Myelinated axons inside of the counting frame and also hit the inclusion line were counted. However, the axons hit the exclusion line or their extension or located outside of the counting frame were not counted. The number of myelinated axons counted was used to calculate the total number of myelinated axons in the nerve using the following formula.
Toxicology of long‐term and high-dose administration of methylphenidate on the kidney tissue – a histopathology and molecular study
Published in Toxicology Mechanisms and Methods, 2020
Amir Raoofi, Ali Delbari, Davood Mahdian, Mohammad-Shafi Mojadadi, Abdollah Amini, Sara Sadat Javadinia, Ghazaleh Dadashizadeh, Behnaz Ahrabi, Vahid Ebrahimi, Amin Mousavi Khaneghah
To evaluate the impacts of MPH on the kidney’s renal corpuscle, we used a histological procedure employing the staining of Hematoxylin and Eosin. Stereology study was done to provide more quantitative information. Figures 1 and 2 showed the H&E images along the cross-sections cut from the kidney tissue in different groups after three weeks. Administration of MPH causes a critical decline in the mean diameter of Renal corpuscle (Figure 1(A–C)) and Bowman’s space thickness (Figure 2(A–C)) in MPH treated group (Respectively 80.1 ± 6.2 and 4.5 ± 0.78) compared with the control (Respectively 96.1 ± 4 and 7.1 ± 0.25), after injection of MPH, illustrate the occur of glomerular damage in renal. Furthermore, stereological counting of the renal corpuscle in the kidney displayed a significant decrease in the volume glomerular (p-value < 0.05) and thickness of Bowman’s space (p-value < 0.05) compared to the control (Figures 1 and 2).
Ameliorative effects of quercetin on folliculogenesis in diabetic mice: a stereological study
Published in Gynecological Endocrinology, 2020
Ayeh Bolouki, Fatemeh Zal, Hossein Bordbar
Estimation of the total ovarian volume, ‘V (Ref)’, was made according to the Cavalieri principle and via a stereomicroscope connected to a computer, at the final magnification of ×20. Eight–twelve sections from each ovary were sampled. A test system of points was overlaid on the image of the tissue using the stereology software designed at our research center. The estimation was made using the following formulas: t’ is the distance between the sampled sections and the section thickness, ΣPi is the total number of points hitting the sections of the ovary, and ‘a(p)’ is the area per point which is calculated by multiplying ‘ΔX’ by ‘ΔY’. The arrow indicates the point which is at the right upper corner of the cross.