A rapid phosphotungstic acid staining method on ultra-thin sections

1994 ◽  
Vol 52 ◽  
pp. 318-319
Author(s):  
K. Chien ◽  
R. L. Van de Velde ◽  
R.C. Heusser ◽  
H. Shiroishi ◽  
A.H. Cohen
Keyword(s):  
Room Temperature ◽  
Phosphotungstic Acid ◽  
Staining Method ◽  
Tap Water ◽  
Petri Dish ◽  
Hereditary Disease ◽  
Microwave Oven ◽  
Staining Procedure ◽  
Thin Sections ◽  
Nail Patella Syndrome

The Nail-Patella Syndrome (NPS) is an autosomal dominant hereditary disease in which about 60% of the patients have glomerular abnormalities. Phosphotungstic acid (PTA) has been used successfully to demonstrate the specific collagen fibrils of NPS within the glomerular basement membrane and/or mesangial matrix in ultra-thin sections. However, in our laboratory we had difficulty staining Eponate 12 sections with PTA. A modified staining procedure which makes use of the microwave has been developed as follows:1. Glutaraldehyde/osmium fixed kidney specimens were embedded in Eponate 12 and ultra-thin sections collected on Gilder 400 mesh copper grids. Grids were stained using a RTV 700 silicone rubber staining pad. This pad contains shallow, round wells (5mm in diameter and 2mm deep) with slots in the center bottom of each well. By bending the pad, the rim of a grid can be inserted into the slot. On release, the grids adhere securely to the wall of the slot.2. 10% aqueous phosphotungstic acid was dropped into the staining wells around each grid. The staining pad was then placed in a moisture chamber consisting of a pre-heated Petri dish containing wetted filter paper and placed in Pelco 3400 laboratory microwave oven for 110 seconds at 80% power. A Tripour beaker containing 200ml room temperature tap water was placed in the microwave oven as a heat sink.

The detection of imidazoles including histidine and some of its derivatives in biological fluids

1969 ◽  
Vol 47 (1) ◽  
pp. 7-10 ◽  
Author(s):  
Arthur E. Pasieka ◽  
M. E. Thomas
Keyword(s):  
Amino Acids ◽  
High Voltage ◽  
Mercuric Chloride ◽  
Staining Method ◽  
Tap Water ◽  
Biological Fluids ◽  
The Other ◽  
Synthetic Mixture ◽  
Bromophenol Blue ◽  
Staining Procedure

A staining method for the detection of imidazoles including histidine and histidine-containing compounds is described. It is based on the treatment of developed high-voltage paper electrograms or paper chromatograms with bromophenol blue. The electrogram or chromatogram after drying is fixed in n-butanol, complexed with mercuric chloride, and subsequently stained with 0.2% bromophenol blue in 95% ethanol. The electrogram or chromatogram is washed while still damp with tap water until the background is clear. None of the other 20 known amino acids including tyrosine, such as are found in the synthetic mixture M150, reacted in the above staining procedure. Purines also react with the described reagent due to their imidazole configuration.

Ultrastructure and Staining of Developing Elastic Tissue

1971 ◽  
Vol 29 ◽  
pp. 244-245
Author(s):  
E. N. Albert
Keyword(s):  
Fine Structure ◽  
Phosphotungstic Acid ◽  
Staining Method ◽  
Rat Aorta ◽  
Uranyl Acetate ◽  
The Other ◽  
Elastic Fibers ◽  
Elastic Tissue ◽  
Lead Citrate ◽  
New Born

Silver tetraphenylporphine sulfonate (Ag-TPPS) was synthesized in this laboratory and used as an electron dense stain for elastic tissue (Fig 1). The procedures for the synthesis of tetraphenylporphine sulfonate and the staining method for mature elastic tissue have been described previously.The fine structure of developing elastic tissue was observed in fetal and new born rat aorta using tetraphenylporphine sulfonate, phosphotungstic acid, uranyl acetate and lead citrate. The newly forming elastica consisted of two morphologically distinct components. These were a central amorphous and a peripheral fibrous. The ratio of the central amorphous and the peripheral fibrillar portion changed in favor of the former with increasing age.It was also observed that the staining properties of the two components were entirely different. The peripheral fibrous component stained with uranyl acetate and/or lead citrate while the central amorphous portion demonstrated no affinity for these stains. On the other hand, the central amorphous portion of developing elastic fibers stained vigorously with silver tetraphenylporphine sulfonate, while the fibrillar part did not (compare figs 2, 3, 4). Based upon the above observations it is proposed that developing elastica consists of two components that are morphologically and chemically different.

Lattice imaging and pore structure of β ferric oxyhydroxide

1978 ◽  
Vol 36 (1) ◽  
pp. 264-265
Author(s):  
T. Baird ◽  
J.R. Fryer ◽  
S.T. Galbraith
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bulk Material ◽  
Model Structure ◽  
Bulk Crystals ◽  
Lattice Imaging ◽  
Thin Sections ◽  
Ferric Oxyhydroxide ◽  
Resolution Electron ◽  
Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

Immunogold localization of HMB-45 antigen in pulmonary lymphangiomyomatosis

1995 ◽  
Vol 53 ◽  
pp. 998-999
Author(s):  
J.M. Minda ◽  
E. Dessy ◽  
G. G. Pietra
Keyword(s):  
Smooth Muscle ◽  
Smooth Muscle Cells ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Muscle Cells ◽  
Ultrastructural Localization ◽  
Reproductive Age ◽  
Thin Sections ◽  
Smooth Muscle Proliferation ◽  
Hmb 45

Pulmonary lymphangiomyomatosis (PLAM) is a rare disease occurring exclusively in women of reproductive age. It involves the lungs, lymph nodes and lymphatic ducts. In the lungs, it is characterized by the proliferation of smooth muscle cells around lymphatics in the bronchovascular bundles, lobular septa and pleura The nature of smooth muscle proliferation in PLAM is still unclear. Recently, reactivity of the smooth muscle cells for HMB-45, a melanoma-related antigen has been reported by immunohistochemistry. The purpose of this study was the ultrastructural localization of HMB-45 immunoreactivity in these cells using gold-labeled antibodies.Lung tissue from three cases of PLAM, referred to our Institution for lung transplantation, was embedded in either Poly/Bed 812 post-fixed in 1% osmium tetroxide, or in LR White, without osmication. For the immunogold technique, thin sections were placed on Nickel grids and incubated with affinity purified, monoclonal anti-melanoma antibody HMB-45 (1:1) (Enzo Diag. Co) overnight at 4°C. After extensive washing with PBS, grids were treated with Goat-anti-mouse-IgG-Gold (5nm) (1:10) (Amersham Life Sci) for 1 hour, at room temperature.

Otoconia perfect/imperfect crystals

1994 ◽  
Vol 52 ◽  
pp. 42-43
Author(s):  
César D. Fermin ◽  
Dale Martin
Keyword(s):  
Image Processing ◽  
Room Temperature ◽  
Phosphotungstic Acid ◽  
Gallus Domesticus ◽  
Crystal Matrix ◽  
Organic Templates ◽  
Image Processing Algorithms ◽  
Processing Algorithms ◽  
Diffraction Patterns

Otoconia of higher vertebrates are interesting biological crystals that display the diffraction patterns of perfect crystals (e.g., calcite for birds and mammal) when intact, but fail to produce a regular crystallographic pattern when fixed. Image processing of the fixed crystal matrix, which resembles the organic templates of teeth and bone, failed to clarify a paradox of biomineralization described by Mann. Recently, we suggested that inner ear otoconia crystals contain growth plates that run in different directions, and that the arrangement of the plates may contribute to the turning angles seen at the hexagonal faces of the crystals.Using image processing algorithms described earlier, and Fourier Transform function (2FFT) of BioScan Optimas®, we evaluated the patterns in the packing of the otoconia fibrils of newly hatched chicks (Gallus domesticus) inner ears. Animals were fixed in situ by perfusion of 1% phosphotungstic acid (PTA) at room temperature through the left ventricle, after intraperitoneal Nembutal (35mg/Kg) deep anesthesia. Negatives were made with a Hitachi H-7100 TEM at 50K-400K magnifications. The negatives were then placed on a light box, where images were filtered and transferred to a 35 mm camera as described.

Observations of thick and thin sections in a field-emission SEM

1994 ◽  
Vol 52 ◽  
pp. 1018-1019
Author(s):  
W. P. Wergin ◽  
S. Roy ◽  
E. F. Erbe ◽  
C. A. Murphy ◽  
C. D. Pooley
Keyword(s):  
Electron Microscope ◽  
Field Emission ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Chemical Fixation ◽  
Thin Sections ◽  
Transmission Electron ◽  
Conventional Transmission Electron Microscope ◽  
Scanning Electron

Larvae of the nematode, Steinernema carpocapsae Weiser strain All, were cryofixed and freezesubstituted for 3 days in acetone containing 2% osmium tetroxide according to established procedures. Following chemical fixation, the nematodes were brought to room temperature, embedded in Spurr's medium and sectioned for observation with a Hitachi S-4100 field emission scanning electron microscope that was equipped with an Oxford CT 1500 Cryotrans System. Thin sections, about 80 nm thick, similar to those generally used in conventional transmission electron microscope (TEM) studies were mounted on copper grids and stained with uranyl acetate for 30 min and lead citrate for 5 min. Sections about 2 μm thick were also mounted and stained in a similar fashion. The grids were mounted on an Oxford grid holder, inserted into the microscope and onto a cryostage that was operated at ambient temperature. Thick and thin sections of the larvae were evaluated and photographed in the SEM at different accelerating voltages. Figs. 4 and 5 have undergone contrast conversion so that the images would resemble transmitted electron micrographs obtained with a TEM.

Solvent-assisted osmium staining of butyl acrylate and ethylene-propylene-diene in a styrene acrylonitrile matrix

1993 ◽  
Vol 51 ◽  
pp. 900-901 ◽  
Author(s):  
Gudrun A. Hutchins
Keyword(s):  
Butyl Acrylate ◽  
Room Temperature ◽  
Osmium Tetroxide ◽  
Staining Procedure ◽  
Reactive Site ◽  
Ethylene Propylene ◽  
Minimal Distortion ◽  
Styrene Acrylonitrile ◽  
Engineering Polymers ◽  
Effective Reaction

In order to optimize the toughening effect of elastomers in engineering polymers, it is necessary to characterize the size, morphology and dispersion of the specific elastomer within the polymer matrix. For unsaturated elastomers such as butadiene or isoprene, staining with osmium tetroxide is a well established procedure. The residual carbon-carbon double bond in these materials is the reactive site and forms a 1,2-dilato complex with the OsO4. Incorporation of osmium tetroxide into the elastomer not only produces sufficient contrast for TEM, but also crosslinks the elastomer sufficiently so that ultramicrotomy can be accomplished at room temperature with minimal distortion.Blends containing saturated elastomers such as butyl acrylate (BA) and ethylene propylene diene monomer (EPDM) cannot be stained directly with OsO4 because effective reaction sites such as C=C or -NH2 are not available in sufficient number. If additional reaction sites can be introduced selectively into the elastomer by a chemical reaction or the absorption of a solvent, a modified, two-step osmium staining procedure is possible.

Membranes in lupin root nodules. II. Preparation and properties of peribacteroid membranes and bacteroid envelope inner membranes from developing lupin nodules

1978 ◽  
Vol 30 (1) ◽  
pp. 151-174
Author(s):  
J.G. Robertson ◽  
M.P. Warburton ◽  
P. Lyttleton ◽  
A.M. Fordyce ◽  
S. Bullivant
Keyword(s):  
Sucrose Gradient ◽  
Phosphotungstic Acid ◽  
Nadh Oxidase ◽  
Osmotic Shock ◽  
Root Nodules ◽  
Freeze Fracture ◽  
Electrophoretic Analysis ◽  
Thin Sections ◽  
Peribacteroid Space ◽  
Gradient Fractionation

Peribacteroid membranes and bacteroid envelope inner membranes have been isolated from developing lupin nodules. Isolation of the peribacteroid membranes was achieved by first preparing membrane-enclosed bacteroids free from other plant organelles or membranes. The peribacteroid membranes were then released by osmotic shock and purified by centrifugation to equilibrium on sucrose gradients. The bacteroids were broken in a pressure cell and the bacteroid envelope inner membranes were isolated using sucrose gradient fractionation of the bacteroid total envelope preparation. The density of the peribacteroid membranes decreased during the period of development of N2-fixation in lupin nodules from 1.148 g/ml for nodules from 12-day plants to 1.137 g/ml for nodules from 18-day plants. The density of the bacteroid envelope inner membranes from nodules from 18-day plants was 1–153 g/ml. The identity and homogeneity of the isolated membranes was established, by comparison with membranes in intact nodules, using phosphotungstic acid and silver staining of thin sections and particle densitites on faces of freeze-fracture replicas of the membranes. Analyses for NADH oxidase and succinate dehydrogenase, spectral analyses and gel-electrophoretic analysis of proteins were also used to characterize the membrane and soluble protein fractions from the nodules. The ratio of lipid to protein was 6.1 for the peribacteroid membranes and 2.5 for the bacteroid envelope inner membranes. Leghaemoglobin was localized in the plant cytoplasm in lupin nodules and not in the peribacteroid space.

scholarly journals Determining the most effective common household disinfection method to reduce the microbial load on domestic dishcloths: a pilot study

2021 ◽  
Vol 63 (4) ◽  
pp. 101-106
Author(s):  
Emily Gillies
Keyword(s):  
Pilot Study ◽  
Confidence Intervals ◽  
High Power ◽  
Room Temperature ◽  
Tap Water ◽  
Lemon Juice ◽  
Foodborne Illness ◽  
Cross Contamination ◽  
Disinfection Methods ◽  
Significant Difference

The domestic dishcloth has been shown to be the most contaminated item in the domestic kitchen, reported to contain up to 108 bacteria for up to 48 hours. Their smooth texture and large surface area allow bacteria to be transferred to kitchen surfaces easily, presenting a greater risk of cross-contamination and potentially contributing to foodborne illness. The purpose of this pilot study was to determine the most effective method to decrease the aerobic colony count (ACC) present on contaminated dishcloths. Dishcloths were inoculated in a beef slurry for 48 hours at room temperature. Contaminated dishcloths were subjected to 1-minute treatments of 10% bleach solution, lemon juice, vinegar, tap water, and microwaving. Serial dilutions were plated and incubated at 37°C overnight. Three replicates were produced, and 95% confidence intervals were calculated. Although treatments of 10% bleach solution and vinegar showed reduced ACC growth, no growth was identified after microwaving dishcloths for 1 minute on high power. There was no significant difference identified between the tap water and lemon juice treatments. Given that this is the first study conducted directly comparing different disinfection methods for dishcloths, microwaving dishcloths on high power for 1 minute can be recommended to disinfect domestic dishcloths and reduce cross-contamination within the home.

scholarly journals Kenaf Fibre Reinforced Polypropylene Composites: Effect of Cyclic Immersion on Tensile Properties

2015 ◽  
Vol 2015 ◽  
pp. 1-6 ◽  
Author(s):  
W. H. Haniffah ◽  
S. M. Sapuan ◽  
K. Abdan ◽  
M. Khalid ◽  
M. Hasan ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Tensile Properties ◽  
Room Temperature ◽  
Tap Water ◽  
Tensile Modulus ◽  
Polypropylene Composites ◽  
Preliminary Results ◽  
Kenaf Fibre ◽  
The Difference ◽  
Number Of Cycles

This research studied the degradation of tensile properties of kenaf fibre reinforced polypropylene composites due to cyclic immersion into two different solutions, as well as comparison of the developed composites’ tensile properties under continuous and cyclic immersion. Composites with 40% and 60% fibre loadings were immersed in tap water and bleach for 4 cycles. Each cycle consisted of 3 days of immersion and 4 days of conditioning in room temperature (28°C and 55% humidity). The tensile strength and modulus of composites were affected by fibre composition, type of liquid of immersion, and number of cycles. The number of immersion cycles and conditioning caused degradation to tensile strength and modulus of kenaf fibre reinforced polypropylene composites. Continuous and cyclic immersion in bleach caused tensile strength of the composites to differ significantly whereas, for tensile modulus, the difference was insignificant in any immersion and fibre loadings. However, continuous immersion in the bleach reduced the tensile strength of composites more compared to cyclic immersion. These preliminary results suggest further evaluation of the suitability of kenaf fibre reinforced polypropylene composites for potential bathroom application where the composites will be exposed to water/liquid in cyclic manner due to discontinuous usage of bathroom.

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