bluuebunny/crossref_metadata_2025_split huggingface dataset:
A new method for cell culture on an electron‐transparent melamine foil suitable for successive LM, TEM and SEM studies of whole cells
Authors: Westphal Christel , Hörler Heide , Pentz Siegwald , Frösch Dieter 
Published: August 2011

SUMMARYA new cell culture technique is described which is based on the observation that foils cast from the melamine resin hexamethylol‐melamine‐ether are suitable for the cultivation of beating heart muscle cells and fibroblasts of the rat. This foil can be flamed for sterilization, is about 80 nm in thickness, homogeneous and smooth, withstands dehydration and critical point‐drying, can be removed from glass and permits the imaging of whole cells successively by light microscopy, transmission and scanning electron microscopy.The method is capable of narrowing the gap between light and electron microscopy, yielding excellent whole cell preparations in various kinds of microscopic studies to be performed on one and the same cell.
Anterograde tracing in the brain using autoradiography and HRP‐histochemistry. A comparison at the ultrastructural level
Authors: Holstege J. C. , Vrensen G. F. J. M. 
Published: August 2011

SUMMARYThe present paper decribes the use of 3H‐leucine and WGA‐HRP as anterograde tracers in the brain at the ultrastructural level. In addition the different aspects of the two tracing techniques are compared, including the analysis of the results, the reliability and relative efficiency.
Video microscopic image processing facilitates the evaluation of light microscopic autoradiography at high magnification
Authors: Montag M. , Trendelenburg M. F. , Spring H. 
Published: August 2011

SUMMARYLight microscopic autoradiographs of H‐thymidine labelled unstained semithin sections of Xenopus laevis embryonic nuclei were examined with conventional Nomarski differential interference contrast, phase‐contrast and video microscopy.Whereas at low magnification it was possible to obtain a photograph of the nuclear structure and the silver grains in one focal plain, at high magnification, with small depths of focus, a satisfactory image was not attainable. Therefore, we stored the images of the two different focus levels with a digital image processing system and combined both images by an arithmetic operation.This video microscopic technique allows the use of high magnification light microscopy with oil immersion objectives and the application of additional electronic contrast enhancing methods for an adequate and rapid analysis of light microscopic autoradiographs.
Stereological estimation of mean nuclear volume in prostatic cancer, the reproducibility and the possible value of estimations on repeated biopsies in the course of disease
Authors: Nielsen K. , Berild G. H. , Bruun E. , Jorgensen P. E. , Weis N. 
Published: August 2011

SUMMARYThe reproducibility of stereological estimates of mean nuclear volume by using the principle of volume estimation of particles of arbitrary shape is investigated together with the possible prognostic value of the estimates in the course of advanced prostatic cancer.Repeated transurethral resection of the prostate was performed 14–93 months after the first resection in 14 of 85 consecutive patients in whom prostatic cancer was newly diagnosed in the period 1979–1983. Twelve of these fourteen patients needed endocrine treatment because of progression of the metastatic disease.The reproducibility of the estimations was excellent as the variation of the method was less than 1 % when the estimation of the mean nuclear volume was repeated at random on the same specimens after a time‐interval of 2 months.The progression of the disease was evidenced by a significant histological upgrading and by a highly significant increase of the mean nuclear volume from the first to the second transurethral resection of the prostate.
An investigation of the fixation and staining of lipids by a combination of malachite green or other triphenylmethane dyes with glutaraldehyde
Authors: Lawton June R. 
Published: August 2011

SUMMARYMixtures of the monocationic triphenylmethane dyes, malachite green or crystal violet, with glutaraldehyde, retained and stained phospholipid droplets in chloroplasts of leaves of Lolium multiflorum Lam. These dyes also stained trilinolenin; phosphatidic acid dioleoyl, dipalmitoyl; phosphatidylcholine dioleoyl, dilinoleoyl; and phosphatidylethanolamine dioleoyl on filter paper models. In this model system the dipalmitoyl derivatives of phosphatidylcholine and phosphatidylethanolamine did not stain well, if at all. Washing of the dyed samples with 0.5 M sodium chloride solution did not remove the colour, suggesting that the interaction is unlikely to be purely ionic. Except with trilinolenin, the colour and possibly the lipid samples were removed from the filter paper model system on washing with 100% ethyl alcohol.Other triphenylmethane dyes (methyl green, light green and fast green FCF) did not retain phospholipid droplets in tissue. Fast green did, however, stain phospholipids in the model system. Two quinone‐imine dyes, neutral red and toluidine blue O, while staining phospholipids in the model system did not retain droplets on the chloroplasts but did assist in the retention and staining of cell membranes.The basis of the reaction between lipid and dye is discussed in relation to the structural formulae of the dyes and model lipids. It is possible that there is an interaction between the hydrophobic fatty acid ester side chains of the lipid and the dyes. Neither the phosphate nor the polyhydric alcohol moieties of the lipid seem to be essential for staining or retention of lipid.
An improved method for collecting and staining microorganisms for enumeration by fluorescence light microscopy
Authors: Williamson F. A. , Palframan K. R. 
Published: August 2011

SUMMARYA rapid, robust method for the enumeration of total and viable microorganisms is described. A method using specific stains for viable and total cells and fluorescence light microscopy on membrane filters had been previously developed, but was sub‐optimal in that some non‐specific staining of the filters occurred and the filters were not flat enough for automatic image analysis methods to be employed, because not all cells in a field of view were in focus simultaneously.A new membrane filter has recently become available: the Anopore† membrane was described by the manufacturers as having a number of properties which would overcome these limitations. These include inorganic construction (giving resistance to solvents), high porosity (giving high flow rates), low surface adsorption (giving low background staining) and inherent hydrophilicity (simplifying wetting with aqueous solutions).Anopore membrane filters were found to produce very high contrast images of bacteria stained with ethidium bromide. Even with a relatively low power (magnification = 40) dry objective, these images could be easily thresholded for image analysis using only grey‐level information. The methods developed here are considered to be a suitable basis for a fully automated procedure for the enumeration of total microbial populations.
Precision of area estimation: a numerical study
Authors: Matérn Bertil 
Published: August 2011

SUMMARYAfter listing some general formulae for sampling in n‐dimensional space, the author considers the one‐dimensional case: the estimation of the length of a line segment by counting the number of points that happen to fall within the segment. If the points are equidistantly located, the variance of the estimate is a strictly periodic function of the length of the segment. This systematic sample has a higher efficiency than simple and stratified random samples of the same intensity.With some modifications, the results carry over to the two‐dimensional case: the estimation of the area of a plane figure by counting the number of sample points falling inside the figure. However, the strict periodicity of the variance in the one‐dimensional systematic case is replaced by a ‘Zitterbewegung’. The magnitude of this oscillation is seen to be very different for figures of different shapes.Some results are presented also for the estimation of areas by line transects, and for the estimation of volumes by aid of lattices of points in R3, and R4. Some comments are also given on the practical implications of the results for sampling in the plane.
A review of the determination of dislocation parameters using strong‐ and weak‐beam electron microscopy
Authors: Nikolaichick V. I. , Khodos I. I. 
Published: August 2011

SUMMARYThis paper reviews the results of the investigation of dislocation image characteristics as formed using strong‐ and weak‐beam transmission electron microscopy as well as the application of these data for the determination of the basic dislocation parameters: the value, direction and sign of the Burgers vector, and the dissociation width of dislocations split into Shockley partials. The relative advantages and limitations of strong‐ and weak‐beam techniques in studies of dislocation parameters are discussed. This is exemplified by an examination of the possibility of revealing dislocation dissociation with separation Δ 10 nm using strong diffracted beams. The influence of the anisotropy of the elastic moduli on the strong‐beam images of dissociated dislocations is also discussed. The effects of the column approximation on the calculated weak‐beam images of dissociated dislocations are analysed using the results of non‐column calculations. The statistical analysis of the measured dissociation values is also described, allowing the enhancement of the precision of the weak‐beam measurements and their sensitivity in revealing small variations in dissociation width. Finally, the differences in the form of weak‐beam images of dissociated dislocations and of ordinary and faulted dipoles are discussed.
Application of the disector method in the light microscopic quantification of type II pneumocytes in control and ozone‐exposed rats
Authors: Dormans J. A. M. A. 
Published: August 2011

SUMMARYAlveolar type II cells in control and ozone‐exposed rat lungs were counted at the light microscopical level with the ‘disector method’. The type II cells were unequivocally marked by histochemical staining for alkaline phosphatase activity in 2 μm plastic sections. By this counting method, the mean number of type II cells per lung in control rats was of the same magnitude as those reported in the literature, using point counting methods. After exposure of rats to 1.6 mg ozone/m3 for 7 days, a 50% increase in the mean number of type II cells was observed.The use of the disector method at the light microscopical level offers some advantages above a quantification at the electron microscopical level. The procedure is less time‐consuming, larger areas can be screened, two parallel countings can be performed in one set of sections and there is no need for an exact knowledge about the diameter of the measured particle.
Spatial orientation of arterial sections determined from aligned vascular smooth muscle
Authors: Finlay H. M. , Whittaker P. , Hicks J. G. , Taylor C. P. S. , Park Y. W. , Canham P. B. 
Published: August 2011

SUMMARYThe alignment of the arterial axis can be used as the required reference for three‐dimensional (3‐D) measurements of structures within the artery wall. Our hypothesis is that this alignment reference may be derived mathematically if one uses medial smooth muscle, a tissue component we have found to have a circumferential organization in human cerebral and coronary arteries. We tested this hypothesis for angles of sectioning up to 60°, using arteries fixed at normal distending pressure. These segments of artery were sectioned at precisely measured angles, using a specially designed mitre box, and the sections were stained to enhance birefringence of the smooth muscle. Arteries from eleven autopsies were obtained from the heart and brain, and measurements of 3‐D orientation on medial smooth muscle were made with a polarizing light microscope equipped with a four‐axis Universal stage. By comparing the cutting angle, derived from our mathematically obtained values, to the predetermined cutting angle, we deduce that we can determine the obliqueness of cut relative to the arterial axis to within 4.6°. The application that is important to us, and possibly to other laboratories, is that the necessary direction reference for an artery is completely contained within a single tissue section.
Triumphs and conflicts in microscopy
Authors: Hartley W. G. 
Published: August 2011

SUMMARYThe controversies surrounding the Abbe theory and its final acceptance are discussed. The practical problems of lens design and manufacture, the rise and fall of the ultraviolet microscope and reflecting microscope and the development of fluorescence microscopy are briefly surveyed. In particular, the conflicts which arose between Fellows of singular or opposing views—E. M. Nelson, A. E. Conrady, J. W. Gordon—are presented as illustrative of the failure to recognize the nature of the point at issue.
The electron microscope: The British contribution
Authors: Mulvey Tom 
Published: August 2011

SUMMARYThe unpredictable development of the electron microscope is reviewed in the context of the 150th Anniversary of the Royal Microscopical Society. Abbe convinced himself that an electron microscope could never be constructed. Later, J. J. Thomson established the minute corpuscular nature of the electron and Rutherford realized that such beams can reveal the nature of the atom; his student H. G. Moseley invented electron probe analysis, while looking for X‐ray spectra, but the technique did not seem very practical. G. P. Thomson invented the electron diffraction camera, but it was of limited use without an electron lens. In 1931, Knoll and Ruska built a two‐stage TEM with magnetic lenses and understood where Abbe went wrong. Although Ernst Ruska surpassed the resolving power of the light microscope in 1933, the first commercial TEM was manufactured in the U.K., leading to many further commercial developments. The realization of a digital computer with a stored program, now indispensible in microscopy, was also achieved first in the U.K. Gabor's electron beam holography, invented in Rugby in 1949, was not a challenge to the conventional TEM at first, but recently atomic resolution holography has been achieved in Abbe's native country, using a digital computer to process the hologram, ironically making use of the very principles laid down by Abbe in the last century for the light microscope.
Measuring through the microscope: Development and evolution of stereological methods
Authors: Weibel Ewald R. 
Published: August 2011

SUMMARYObtaining, by means of microscopy, meaningful measurements pertaining to spatial structures requires methods which allow three‐dimensional quantitative information to be derived from the reduced information available on the two‐dimensional flat sections of the structure. The most powerful methods to that effect are those of stereology which are based on mathematical principles. This paper reviews the early invention of these methods, which sought to solve practical problems, and their further evolution as more rigorous mathematical foundations were developed. It is demonstrated that stereological methods are essentially sampling methods and that newer trends provide new and sound solutions to old and elusive problems, such as anisotropy or particle number and size.
Contrast definition and contour detection for logarithmic images
Authors: Jourlin Michel , Pinoli Jean‐Charles , Zeboudj Rachid 
Published: August 2011

SUMMARYLogarithmic images, such as images obtained by transmitted light or those produced by the human visual system, differ from linear images. Their processing and analysis require consequently specific laws and structures. The latter have been developed in the concept of a logarithmic image processing (LIP) model (Jourlin & Pinoli, 1987, 1988; Pinoli, 1987a). This model permits the introduction of a well‐justified contrast definition: from a physical point of view, it is closely linked with logarithmic images and from a mathematical point of view, it is set up in an algebraic structure.The applications presented at the end of this paper concern image preprocessing and segmentation. In particular, in the case of microscopic images, the proposed method of segmentation gives good results with transmitted light (thin foils in biology or transmitted electronic microscopy). However, images obtained by reflected light microscopy are not within the scope of this model.
Microcomputer system for ion microscopy digital imaging and processing
Authors: Olivo J. C. , Kahn E. , Halpern S. , Briancon C. , Fragu P. , DiPaola R. 
Published: August 2011

SUMMARYAnalytical ion microscopy is a powerful tool for biological tissue analysis as it allows direct chemical distribution imaging, even at low element concentrations. A microcomputer based digital imaging system achieving acquisition at low light level is presented. It includes a high sensitivity video camera connected to a specialized image processor subsystem. Acquired images consist of 512 times 512 pixels with 8 bits accuracy. Real‐time image processing software has been implemented so that image processing may be performed on‐line. Image processing software allows off‐line image manipulation and correlation for biological interpretation of elemental mapping images. System capabilities are illustrated by a study of stable and radio iodine mapping in rat thyroid tissue.
A method for measuring the various constituents of the human hair follicle
Authors: Corcuff P. , Roguet R. , Kermici M. 
Published: August 2011

SUMMARYHair follicles from scalp biopsies (temporal and parietal regions) were isolated by microdissection. This technique allows preservation of the whole structure of the follicle in its fibrous sheath, or isolation of certain elements: bulb and dermal papilla.Each follicle is examined by transmission optical microscopy and its image is digitized into sixty‐four grey levels by an image analyser. Follicle images are memorized on a hard disc, then recalled individually for measurement.The image analysis consists of thresholding, interactive selecting, then measurement of the following elements: diameter of the hair follicle, volume of the bulb, height of the keratogenous zone, mean diameter of the hair and size of the dermal papilla. These parameters were related to a clinical classification (terminal, dystrophic, vellus). This morphometric study constitutes an objective approach which is different from, but complementary, to the classic trichogram (telogen/anagen).
The use of local entropy measures in edge detection for cytological image analysis
Authors: Barba Joseph , Jeanty Henrick , Fenster Paul , Gil Joan 
Published: August 2011

SUMMARYAccurate edge detection is a fundamental problem in the areas of image processing and pattern recognition/classification. The lack of effective edge detection methods has slowed the application of image processing to many areas, in particular diagnostic cytology, and is a major factor in the lack of acceptance of image processing in service orientated pathology. In this paper, we present a two‐step procedure which detects edges. Since most images are corrupted by noise and often contain artefacts, the first step is to clean up the image. Our approach is to use a median filter to reduce noise and background artefacts. The second operation is to locate image pixels which are ‘information rich’ by using local statistics. This step locates the regions of the image most likely to contain edges. The application of a threshold can then pin‐point those pixels forming the edge of structures of interest. The procedure has been tested on routine cytologic specimens.
Countercurrent plunge cooling: A new approach to increase reproducibility in the quick freezing of biological tissue
Authors: Murray P. W. Le R. , Robards A. W. , Waites P. R. 
Published: August 2011

SUMMARYConditions fulfilling all the accepted criteria for optimum cryoquenching are realized for the first time in a plunge freezing device. Samples are plunged down through a smoothly rising cryogen stream that is maintained within ± 0.25 K of a preselected temperature. Dry nitrogen gas at ambient temperature removes evaporated cryogen molecules from the plunging path immediately above the liquid coolant to prevent pre‐cooling of the sample. Symmetrical instrument design and conditions of flow ensure symmetrical freezing under optimum conditions in a totally repeatable fashion. The device has been used with halocarbons, propane and ethane. It provides consistent cooling rates comparable with the best so far obtained by any other plunging method.
Correction for specimen movement after acquisition of element‐specific electron microprobe images
Authors: Lamvik M. K. , Ingram P. , Menon R. G. , Beese L. S. , Davilla S. D. , LeFurgey A. 
Published: August 2011

SUMMARYBecause a long time is generally required to generate X‐ray maps of specific elements by electron beam methods, images are subject to a loss of resolution due to stage movement. Methods have been previously described for correcting stage drift during exposure by sensing the drift and deflecting the beam to follow the stage; but these methods require modifications of the equipment. When the drift is not excessive, it is possible to correct a series of images after the exposure series is finished. Here we demonstrate two methods for correcting the drift, one based on manual assignment of specimen position and one on the use of cross‐correlation functions to determine objectively the misalignment of images in the series. The success of the methods is illustrated in calcium‐specific images of a bone section that show the collagen periodicity after drift correction.
The relative intensities of electron diffraction maxima in mixed rare‐earth oxides
Authors: Schaffer G. B. , Loretto M. H. , Smallman R. E. 
Published: August 2011

SUMMARYThe relative intensities of electron diffraction maxima from yttrium aluminium perovskite were analysed in terms of the atomic scattering contribution to the structure factors and in terms of double diffraction. It has been shown that double diffraction influences the visible intensity between diffraction spots in electron diffraction patterns to a greater extent than does the magnitude of the structure factor. A direct consequence of this is that the intensity of diffraction maxima can increase when a specimen is tilted off an exact zone axis.
Ultrathin sectioning for electron microscopy: The distilled water in the knife trough may extract phosphatase reaction products from the sections
Authors: Rostgaard J. , Qvortrup K. 
Published: August 2011

SUMMARYDuring an electron microscopical study of the localization of the nucleoside diphos‐phatase IDPase in Reissner's membrane of the inner ear, it was discovered that the distilled water in the knife trough produced an annoying artefact. It dissolved all the lead phosphate reaction product from the sections, and thus converted a positive phosphatase reactivity to a false negative one. The water in the knife trough had a pH of approximately 5.4.Calculations showed that this is an expected acidity, if CO2 in the air equilibrates with distilled water, and that there is 200,000 times more acid in the trough than necessary to dissolve all the reaction product from a ribbon of ultrathin sections. Experiments showed that the artefact could be avoided by adjusting the pH to neutrality with dilute ammonia.
A new rapid method of air‐drying for scanning electron microscopy using tetramethylsilane
Authors: Dey Sudip , Baul T. S. Basu , Roy B. , Dey D. 
Published: August 2011

SUMMARYA new rapid air‐drying technique which gives results comparable to critical point‐drying is described for scanning electron microscopy, using a trematode parasite, Homalogaster paloniae, as a test specimen.