The Nerve Cell Laid Bare
Andrew P. Wickens in A History of the Brain, 2014
Purkinje’s new microscope soon led to some notable discoveries including an account of sweat glands in 1833, the first observation of ciliary motion in embryonic cells in 1834, and the recognition of the protein-digesting power of pancreatic extracts in 1836. As a reward for his dedicated work, Purkinje was presented with a second high class microscope (built by Pistor and Schiek of Berlin) in 1836, but perhaps more importantly, he received his own university building for research and lecturing in 1839. It was, in effect, the world’s first institute dedicated to microscopical research. Now known as the cradle of histology for its many discoveries, it also housed the world’s first practical microtome – a bladed instrument allowing wafer thin sections of fixed size to be cut for microscopic analysis. This instrument, first constructed under Purkinje’s leadership in 1841,was a major advance, for prior to its invention, microscopists had been forced to manually prepare tissue by using razors. The microtome now allowed reproducible clean cuts to be made of such thinness that light could shine through the tissue allowing its structure to be better visualised. This would prove to be particularly valuable in the examination of nervous material.
Tissue Staining Techniques for Stroke Studies
Yanlin Wang-Fischer in Manual of Stroke Models in Rats, 2008
A microtome is a device used for cutting sections. This device is usually combined with a temperature controller and a water tank. A microtome that slides the specimen across the block is called a sliding microtome. The microtome may be different in each laboratory; rotary microtomes use a rotary actuator to advance the specimen across the blade. The basic theories are the same. We introduce the system from our laboratory as a sample; it includes a water pump and tank unit (PTU-3), temperature controller (Physitemp BFS-30 TC), and microtome (HM 450) (Figure 20.3). This system was purchased from Physitemp Instruments, and with their permission we present some information about it from their Web site (Figure 20.3) (154 Huron Avenue, Clifton, New Jersey 07013, 973–779–5577, 800–452–8510, [email protected]).
Standardization of Herbal Drugs
Ravindra Kumar Pandey, Shiv Shankar Shukla, Amber Vyas, Vishal Jain, Parag Jain, Shailendra Saraf in Fingerprinting Analysis and Quality Control Methods of Herbal Medicines, 2018
There are four main methods for mounting transverse sections. Free hand mounting: This is used for temporary slides. In this method, material is cut with the help of a blade and sliced smoothly from upper left toward lower right in a single motion. Avoid sawing back and forth; keep the specimen and blade lubricated with water.Glide mounting: This method, using a gliding mounting machine, is suitable for lignum, ligneous roots, stems or other solid materials. It is also known as sliding microtome because of its composition of specimen feed, knife, holder, and specimen orientation. The sturdy construction gives it qualities that ensure excellent, reproducible sectioning results. The section thickness and knife inclination and declination can be adjusted.Cryology mounting: This method is mainly used to make slides of animal tissue and fresh and young herbal tissue. Cut the sample into small pieces (about 1–2 cm in diameter) and embed them with cryomatrix on a crycasste; freeze them; slice using a machine; mount on glass slides and seal.Paraffin mounting: This method entails embedding specimens in paraffin, then slicing the block. The steps include sampling, fixing, dehydration, vitrification, olefin immersion, olefin embedding, slicing, removing the paraffin, staining with, for example, safranin and fast green, vitrification after replacing the dyeing solution with a low to high gradient concentration of ethanol, and finally sealing the mounted specimen with gum arabic or neutral gum.
Effect of PEGylation on drug uptake, biodistribution, and tissue toxicity of efavirenz–ritonavir loaded PAMAM G4 dendrimers
Published in Pharmaceutical Development and Technology, 2023
Rohini Kharwade, Nilesh Mahajan, Sachin More, Amol Warokar, Sachin Mendhi, Akshay Dhobley, Devendra Palve
RP-HPLC: LC-20 AD was obtained from Shimadzu (Kyoto, Japan). UV spectrophotometer: UV-1800 was obtained from Shimadzu (Kyoto, Japan). Rotary evaporator was obtained from Buchi Rotavapor R-100 (Buchi, Flawil, Switzerland). Cooling Centrifuge was obtained from REMI Model CM 12 Plus (REMI, Mumbai, India). Lyophilizer was obtained from MAC Lyophilizer (Freeze Dryer) (cat. no.: MSW-137) serial no. 2511 was obtained from Macro Scientific Works Pvt. Ltd. (Delhi, India). Mass spectrophotometer: Synapt XS HDMS, UPLC Acquity H class series system was obtained from Waters (Wilmslow, UK). FE-SEM: JSM-6380A Scanning Electron Microscope; 200 kV was obtained from JEOL Ltd. (Tokyo, Japan). TEM: JEM-2100 Plus Electron Microscope; 200 kV was obtained from JEOL Ltd. (Tokyo, Japan). DSC: Mettler Toledo, DSC1 was obtained from Star e-software (Ramsen, Switzerland). XRD: powder X-ray diffractometer with Ni-filtered, Bruker D2 phaser, 2nd generation was obtained from Bruker (Karlsruhe, Germany). CO2 incubator was obtained from Thermo Scientific Inc. (Waltham, MA). ELISA microplate reader: Benesphera E2 (110–250 V; OSRAM 64607) was obtained from Benesphera (Center Valley, PA). Rotary microtome: Leica Biosystem, Semiautomatic Histocore Rotary Microtome; was obtained from Leica Biosystem (Wetzlar, Germany). Optical microscope: Cilika BT-E (2021); Benchtop Biological Digital microscope was obtained from Medprime Technology Private Ltd. (India).
Corneal targeted fenticonazole nitrate-loaded novasomes for the management of ocular candidiasis: Preparation, in vitro characterization, ex vivo and in vivo assessments
Published in Drug Delivery, 2022
Sadek Ahmed, Maha M. Amin, Sarah Mohamed El-Korany, Sinar Sayed
A histopathological study was performed to notice any corneal tissue injury caused by the optimum formula. The test was conducted on three albino rabbits. In brief, the optimum formula was assessed by comparison to sterile normal saline (negative control) and isopropyl alcohol 95% (positive control). One drop from of normal saline or isopropyl alcohol 95% was applied into one eye of a male albino rabbit. While the optimum formula was applied into the other eye. Application of each liquid was done twice daily for one week (Elsayed & Sayed, 2017; Sayed et al., 2020). Animals were firstly anesthetized as mentioned in ex vivo study. Following sacrificing the animals by decapitation, corneas were removed from the detached eyes and cautiously washed using normal saline to avoid their damage. Corneal tissues were preserved in 10% v/v formalin saline solution till assessment. Solid paraffin cubes enclosing the corneas were obtained by immersing the corneas in molten paraffin, followed by cooling. Thin slices were obtained using a microtome. Eosin and hematoxylin were used as staining agents. A digital light microscope (Leica, Cambridge, UK) was used for the examination of the specimens (Sayed et al., 2021; Sayed et al., 2020).
Human wharton-jelly mesenchymal stromal cells reversed apoptosis and prevented multi-organ damage in a newborn model of experimental asphyxia
Published in Journal of Obstetrics and Gynaecology, 2022
Bilge Kocabiyik, Erkan Gumus, Burcin Irem Abas, Ayse Anik, Ozge Cevik
The prefrontal cortex, hippocampus, cerebellum, heart, lung, liver, and kidney tissues were kept in 4% paraformaldehyde fixative for histological examination and were embedded in paraffin. Sections of 5 microns were taken in the microtome and stained with HE. Histopathologic scores of the damaged tissues were evaluated using a semi-quantitative scoring technique as described previously: score 0 = no obvious damage; score 1 = loss involving ˂ 10% of neurons; score 2 = lesions involving 20–50% of neurons; score 3 = loss involving >50% of neurons (Rattka et al. 2013). Apoptosis measurements were made using the TUNEL method (Sahin Ersoy et al. 2016) by using the In Situ Cell Death Detection Kit (Roche Diagnostics, GmbH, Mannheim, Germany) which is based on the in situ detection of DNA breaks in tissues. The apoptotic cell ratio was calculated using to the following formula: apoptotic ratio = the number of TUNEL-positive cells/the total number of cells.
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