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Fluorescence Imaging And Spectroscopy Of Biomaterials In Air And Liquid By Scanning Near-Field Optical/Atomic Force Microscopy, H. Muramatsu, N. Chiba, K. Nakajima, T. Ataka, M. Fujihira, J. Hitomi, T. Ushiki Sep 1996

Fluorescence Imaging And Spectroscopy Of Biomaterials In Air And Liquid By Scanning Near-Field Optical/Atomic Force Microscopy, H. Muramatsu, N. Chiba, K. Nakajima, T. Ataka, M. Fujihira, J. Hitomi, T. Ushiki

Scanning Microscopy

We have developed scanning near-field optical/atomic force microscopy (SNOM/AFM). The SNOM/AFM uses a bent optical fiber simultaneously as a dynamic force AFM cantilever and a SNOM probe. Resonant frequency of the optical fiber cantilever is 15-40 kHz. Optical resolution of the SNOM/AFM images shows less than 50 nm. The SNOM/ AFM system contains photon counting system and polychrometer/intensified coupled charge devise (ICCD) system to observe fluorescence image and spectrograph of micro areas, respectively. Cultured cells were stained with fluorescein isothiocyanate (FITC)-labeled anti-keratin antibody or FITC-labeled phalloidin after treatment with Triton X-100. Fluorescence and topographic images were obtained in air and …

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Nucleic Acid Detection By In Situ Molecular Immunogold Labeling Procedures, Marc Thiry Sep 1996

Nucleic Acid Detection By In Situ Molecular Immunogold Labeling Procedures, Marc Thiry

Scanning Microscopy

We have recently combined immunogold labeling procedures with molecular biology methods to pinpoint the precise locations of nucleic acids in biological material at the ultrastructural level. These new immunocytological approaches involve the incorporation of labeled nucleotides in the nucleic acids present at the surface of ultrathin sections prior to immunogold labeling. The antibodies used recognize a nucleoside analogue (bromodeoxyuridine) or a hapten (biotin) employed to label nucleotides. Examples of high-resolution detection include DNA or RNA present in different substructures of cell nuclei, and in particular, in adenovirus-induced intranuclear regions of HeLa cells. In addition to being highly sensitive and specific, …

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Freeze-Dried Human Leukocytes Stabilized With Uranyl Acetate During Low Temperature Embedding Or With Oso4 Vapor After Embedding, L. Edelmann, A. Ruf Sep 1996

Freeze-Dried Human Leukocytes Stabilized With Uranyl Acetate During Low Temperature Embedding Or With Oso4 Vapor After Embedding, L. Edelmann, A. Ruf

Scanning Microscopy

Two new simple stabilization procedures for freeze-dried biological material are introduced which are compatible with low temperature embedding (LTE) in Lowicryl. The first method uses a Lowicryl K11M/HM20 mixture supplemented with 0.3% uranyl acetate for LTE. For the second method polymerized Lowicryl blocks containing the freeze-dried material are exposed to OsO4 vapor which penetrates into the Lowicryl block and stabilizes the embedded specimen. The quality of structural preservation is demonstrated with human leukocytes.

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X-Irradiation-Induced Changes Of The Prelysosomal And Lysosomal Compartments And Proteolysis In Ht-29 Cells, Z. Somosy, A. Takáts, G. Bognár, A. L. Kovács, Á. Telbisz, A. Rácz, J. Kovács, G. J. Köteles Sep 1996

X-Irradiation-Induced Changes Of The Prelysosomal And Lysosomal Compartments And Proteolysis In Ht-29 Cells, Z. Somosy, A. Takáts, G. Bognár, A. L. Kovács, Á. Telbisz, A. Rácz, J. Kovács, G. J. Köteles

Scanning Microscopy

As a consequence of external and internal ionizing radiation, lysosome-like bodies have been observed to increase both in size and number in some cell types. We investigated this process by morphological methods (electron microscopy, cationized ferritin uptake, acid phosphatase histochemistry, morphometry) in cultured HT-29 cells. In parallel with these studies, we measured the rate of protein degradation on the basis of 14C-valine release from prelabeled cellular proteins. We found that at 2 and 4 Gy doses of X-irradiation the volume of the vacuolar (probably lysosomal) compartment increased without detectable changes of acid phosphatase activity. A 2 Gy irradiation dose did …

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Ion And Electron Emission From Liquid Metal Sources, H. Niedrig Sep 1996

Ion And Electron Emission From Liquid Metal Sources, H. Niedrig

Scanning Microscopy

In liquid metal ion sources, the emission is located at the apex of a liquid cone (the often so-called Taylor cone), formed by electrostatic forces and surface tension. Reversal of the extraction voltage polarity results in electron emission from the liquid metal surface. For small apex radii, ≤ 1 μm, steady field emission of electrons has been observed, whereas for apex radii ≥ 10 μm, explosive pulsed emission occurs. Since the onset voltage for electron emission has been found to be considerably lower than the critical voltage for the formation of the Taylor cone, it has been concluded that dc …

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Towards In Situ Atomic Force Microscopy Imaging Of Biofilm Growth On Stainless Steel, D. T. Goddard, A. Steele, I. B. Beech Sep 1996

Towards In Situ Atomic Force Microscopy Imaging Of Biofilm Growth On Stainless Steel, D. T. Goddard, A. Steele, I. B. Beech

Scanning Microscopy

Atomic force microscopy (AFM) has been used to visualise the formation of bacterial biofilms on polished surfaces of 316 stainless steel. Imaging under ambient conditions revealed both the bacterial cells and the matrix of exopolymeric substances (EPS). These images exhibited good resolution with cell surface features as small as 30 nm distinguishable. In situ imaging was also carried out, and although the resolution was considerably reduced, images revealing the process of bacteria division have been obtained.

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Microprocessor Technology And Single Event Upset Susceptibility, L.D. Akers Sep 1996

Microprocessor Technology And Single Event Upset Susceptibility, L.D. Akers

Small Satellite Conference

Today's small satellites employ powerful microcircuits to control virtually every aspect of the spacecraft. While these small devices are very capable, they are increasingly vulnerable to heavy ion induced Single Event Upset (SEU). Current technology is not very susceptible to SEUs. The evolution of microdevices is toward lower power and higher speed while spacecraft evolve toward smaller and lighter structures. This combination, along with the increased heavy ion particle fluence associated with large solar flares, will cause tomorrow's microdevices to experience SEU at rates approaching 100 upsets per device per day! To ensure mission success, these small satellites must consider …

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A Comparison Of The Renal Structures Of The Anaconda And The Ball Python, H. Ditrich Sep 1996

A Comparison Of The Renal Structures Of The Anaconda And The Ball Python, H. Ditrich

Scanning Microscopy

The renal vascular system of the Ball python (Python regius) and the anaconda (Eunectes noteus; Serpentes - Squamata) has been investigated using light microscopy, transmission electron microscopy (TEM), and scanning electron microscopy (SEM) of vascular corrosion casts and critical-point dried non-corroded specimens. The average glomerular diameters of these two species differ significantly (anaconda: 59.1 μm, python: 124.3 μm). Also, the relative proportions of the renal tubules are different. These findings can be related to the different habitats of the two species (aquatic versus terrestrial environment).

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Eor: A University Small Satellite For Low Cost Remote Sensing Of Ozone, Ellen Riddle Sep 1996

Eor: A University Small Satellite For Low Cost Remote Sensing Of Ozone, Ellen Riddle

Small Satellite Conference

The Educational Ozone Researcher (EOR) is a small scientific spacecraft designed by students of the Colorado Space Grant College (CSGC) at the University of Colorado at Boulder. EOR was a finalist in the Universities Space Research Association (USRA) Student Explorer Demonstration Initiative (STEDI) program and received Phase 1 funding in the amount of $160K during late 1994 and early 1995. This paper provides a description of the scientific rationale and the design of the EOR mission.

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Atomic Force Microscopy Investigation Of Radiation-Induced Dna Double Strand Breaks, D. Pang, G. Popescu, J. Rodgers, B. L. Berman, A. Dritschilo Sep 1996

Atomic Force Microscopy Investigation Of Radiation-Induced Dna Double Strand Breaks, D. Pang, G. Popescu, J. Rodgers, B. L. Berman, A. Dritschilo

Scanning Microscopy

We have used atomic force microscopy (AFM) to study radiation-induced DNA double strand breaks. Double-stranded plasmid DNA was irradiated with 18-MeV electrons in aqueous buffer, using a medical linear accelerator. Doses of 50, 100, 150, and 200 Gy were delivered to DNA samples, and atomic force microscopy was used to measure the length of each DNA fragment. From these measurements, we obtained the average length of the irradiated DNA for each sample and found a linear-quadratic relationship between the average length and radiation dose.

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A Micro-Raman Spectroscopic Study Of Hydrazine-Treated Human Dental Calculus, H. Tsuda, W. L. Jongebloed, I. Stokroos, J. Arends Sep 1996

A Micro-Raman Spectroscopic Study Of Hydrazine-Treated Human Dental Calculus, H. Tsuda, W. L. Jongebloed, I. Stokroos, J. Arends

Scanning Microscopy

Hydrazine has been used to remove organic components and to isolate the mineral(s) from human calculus. Micro-Raman measurements were performed on the mineral phase. After the hydrazine-treatment, not only a large reduction in fluorescence but also an increase in Raman signal was observed. The treatment was essential in minimizing thermally-induced chemical changes which could otherwise occur to the original calculus mineral due to the intense laser light. The Raman spectral features of the mineral were nearly all identical among the Raman spectra obtained at many randomly-selected sites by the micro-Raman microbe with a lateral resolution of approximately 1 μm, and …

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Combined Bronchoalveolar-Vascular Casting Of The Canine Lung, John A. Nettum Sep 1996

Combined Bronchoalveolar-Vascular Casting Of The Canine Lung, John A. Nettum

Scanning Microscopy

Canine bronchoalveolar and vascular corrosion casts were prepared using unfixed tissue and Dow-Corning Room Temperature Vulcanizing Silastic® 734. The casts were observed using stereo light microscopy and scanning electron microscopy. The casts show the relationship between the vasculature and airway and demonstrate intricate microanatomical details. Also, microvasculature filling was enhanced using unfixed tissue as compared to my previously described technique using fixed tissue. Prewashing the microvasculature with cold phosphate buffered saline appeared to facilitate microvascular filling with silicone rubber. The described method is useful for rapidly making durable models for studying the normal respiratory airway and microvasculature. It should be …

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Application Of Monte Carlo Simulations To Critical Dimension Metrology In A Scanning Electron Microscope, Jeremiah R. Lowney Sep 1996

Application Of Monte Carlo Simulations To Critical Dimension Metrology In A Scanning Electron Microscope, Jeremiah R. Lowney

Scanning Microscopy

The state of the art in Monte Carlo simulations of scanning electron microscope (SEM) signals is reviewed. Two Monte Carlo computer codes were written to simulate the transmitted-, backscattered-, and secondary-electron signals from targets in a scanning electron microscope. The first, MONSEL-11, is applied to semi-infinite lines produced lithographically on multi-layer substrates. The second, MONSEL-111, is an extension to fully three-dimensional targets. Results for a 1 μm step, etched in a silicon substrate are compared with experimental data. The comparisons show that it is possible to obtain edge locations to an uncertainty of less than 10 nm. Simulations were performed …

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Atomic Force Microscopy And Optical Studies Of Organic Thin Films With Hydrogen-Bonded Networks, Arkadi L. Litvin, Valery N. Bliznyuk, Vladimir V. Tsukruk, Suresh Valiyaveettil, David L. Kaplan Sep 1996

Atomic Force Microscopy And Optical Studies Of Organic Thin Films With Hydrogen-Bonded Networks, Arkadi L. Litvin, Valery N. Bliznyuk, Vladimir V. Tsukruk, Suresh Valiyaveettil, David L. Kaplan

Scanning Microscopy

Brewster angle microscopy and atomic force microscopy were used to characterize the surface morphology of thin films in situ or after transfer onto solid supports. Two acids were studied, differing in carboxylic acid head groups, resulting in significantly different morphological features for thin films formed from these two amphiphiles on a Langmuir trough. Differences in self-assembly and domain sizes were correlated with the formation of hydrogen-bonded networks. The influence of surface hydrophobicity or hydrophilicity during deposition on morphology was also characterized, with spherulitic features appearing in some samples.

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Monte Carlo Simulation Of Electron Backscattering In Solids Using A General-Purpose Computer Code, E. Acosta, E. Coleoni, G. Castellano, J. A. Riveros, J. M. Fernández-Varea, F. Salvat Sep 1996

Monte Carlo Simulation Of Electron Backscattering In Solids Using A General-Purpose Computer Code, E. Acosta, E. Coleoni, G. Castellano, J. A. Riveros, J. M. Fernández-Varea, F. Salvat

Scanning Microscopy

A Monte Carlo study of backscattering of kilovolt electrons in solids, a process of primary importance in electron microscopy and surface analytical techniques, is carried out. Simulations have been performed using the general-purpose simulation code PENELOPE (an acronym for "Penetration and ENErgy LOss of Positrons and Electrons"), which generates electron-photon showers in arbitrary materials. A systematic comparison of results from PENELOPE with available experimental data, and with results from simulations with a much more sophisticated code, is given for electron beams with energies between 2.5 and 60 keV and elemental solids with atomic numbers Z = 4 to 92. It …

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Effects Of Castration Upon The Morphology Of The Accessory Sex Organs Of The Male Rat - A Scanning Electron Microscopy Study, R. Wahlqvist, E. Dahl, K. J. Tveter Sep 1996

Effects Of Castration Upon The Morphology Of The Accessory Sex Organs Of The Male Rat - A Scanning Electron Microscopy Study, R. Wahlqvist, E. Dahl, K. J. Tveter

Scanning Microscopy

A systematic, comparative study of the accessory sex glands of the adult male rat after androgen withdrawal was carried out. The changes were investigated by using scanning electron microscopy at different intervals after surgical castration. The main common signs of epithelial cell involution were flattening of the cell surface, reduction of the size and number of microvilli, some blurring of the cell borders, cessation of secretory activity and diminution of the luminal volume of the glands. Overall, confident signs of atrophy were evident after one week, and complete epithelial involution was reached by the third week. The epithelial cell atrophy …

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Emerging Applications Of Fluorescence Spectroscopy To Cellular Imaging: Lifetime Imaging, Metal-Ligand Probes, Multi-Photon Excitation And Light Quenching, Joseph R. Lakowicz Sep 1996

Emerging Applications Of Fluorescence Spectroscopy To Cellular Imaging: Lifetime Imaging, Metal-Ligand Probes, Multi-Photon Excitation And Light Quenching, Joseph R. Lakowicz

Scanning Microscopy

Advances in time-resolved fluorescence spectroscopy can be applied to cellular imaging. Fluorescence lifetime imaging microscopy (FLIM) creates image contrast based on the decay time of sensing probes at each point in a two-dimensional image. FLIM allows imaging of Ca2+ and other ions without the need for wavelength-ratiometric probes. Ca2+ imaging can be performed by FLIM with visible wavelength excitation. Instrumentation for FLIM is potentially simple enough to be present in most research laboratories. Applications of fluorescence are often limited by the lack of suitable fluorophores. New, highly photostable probes allow off-gating of the prompt autofluorescence, and measurement of …

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Scanning Electron Microscopy Of The Accessory Sex Glands Of The Adult Male Rat, R. Wahlqvist, E. Dahl, K. J. Tveter Sep 1996

Scanning Electron Microscopy Of The Accessory Sex Glands Of The Adult Male Rat, R. Wahlqvist, E. Dahl, K. J. Tveter

Scanning Microscopy

This study describes the morphology of the accessory sex glands of the adult male rat as observed by scanning electron microscopy (SEM). The purpose was to obtain a systematic and comparative SEM description of these glands and to evaluate different preparation techniques. A common morphological feature is polyhedral delineation of the cells, which exhibited a variable convexity of their apical surface. The cell apices were more or less studded with microvilli. Nevertheless, it was possible to distinguish the glands by their surface morphology. In the ventral prostate, there was a considerable heterogeneity in cell surface appearance. The lateral lobe bad …

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Hydrogen Atom Extraction And Redeposition On Hydrogen-Terminated Silicon Surface With Scanning Tunneling Microscope At Room Temperature, D. H. Huang, Y. Yamamoto Aug 1996

Hydrogen Atom Extraction And Redeposition On Hydrogen-Terminated Silicon Surface With Scanning Tunneling Microscope At Room Temperature, D. H. Huang, Y. Yamamoto

Scanning Microscopy

We have previously demonstrated that hydrogen atoms on the hydrogen-terminated Si(100)-2xl:H surface can be extracted by applying either positive or negative voltage pulses between an STM tip and the sample surface with a certain tunneling current. This phenomenon suggests that electron excitation and field evaporation both play a role in atom transfer. Under our experimental conditions, hydrogen atoms are extracted in pairs from either a single dimer or from two adjacent dimers in neighboring rows. Hydrogen atoms can also be redeposited onto the Si(100)-2xl:H surface from a tungsten tip, which has picked up hydrogen from the sample surface through the …

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Applications Of Laser Microprobe Mass Spectrometry In Biology And Medicine, Annette Bakker, Luc Van Vaeck, Wim Jacob Aug 1996

Applications Of Laser Microprobe Mass Spectrometry In Biology And Medicine, Annette Bakker, Luc Van Vaeck, Wim Jacob

Scanning Microscopy

Laser microprobe mass spectrometry (LMMS) provides spot analysis with a lateral resolution of 1-5 μm. Focused laser ionisation, combined with mass spectrometry, yields information on elements, molecular identification of inorganic substances, and structural characterisation of organic molecules of typically less than 2-3 kDa. Quantification in complex heterogeneous systems, such as biological materials, is not possible at the present state of the art. The strength of the method lies in the qualitative information on the molecular composition of the analyte, not just element detection, with a lateral resolution at the light microscopy level. The applications of this technique in the field …

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Influence Of Bleeding On Post-Mortem Tenderization Of Fish Muscle During Chilled Storage, M. Ando, A. Nishiyabu, T. Nakagawa, Y. Makinodan Aug 1996

Influence Of Bleeding On Post-Mortem Tenderization Of Fish Muscle During Chilled Storage, M. Ando, A. Nishiyabu, T. Nakagawa, Y. Makinodan

Scanning Microscopy

The influence of bleeding on post-mortem tenderization of fish muscle during storage was studied. Six fish species were used for the present study. Among them, delay of post-mortem tenderization of muscle by bleeding was shown in the pelagic fishes: yellowtail, horse mackerel, and striped jack. On the other hand, bleeding had no influence on the muscle firmness of the bottom fishes: red sea bream, flatfish, and rudder-fish. According to transmission electron microscopy, degradation of pericellular collagen fibrils was delayed in bled yellowtail and horse mackerel. In the case of striped jack, though, collagen fibril degradation could not be observed; slower …

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The Role Of Calcium In The Regulation Of Apoptosis, David J. Mcconkey Aug 1996

The Role Of Calcium In The Regulation Of Apoptosis, David J. Mcconkey

Scanning Microscopy

The recognition that apoptosis is regulated by an evolutionarily conserved set of polypeptides from the nematode Caenorhabditis elegans to humans suggests that a conserved set of biochemical mechanism(s) may also be involved in the response. Early evidence suggested that the endogenous endonuclease implicated in apoptosis in most model systems is Ca2+ -dependent, and subsequent work from a number of independent laboratories suggests that alterations in cytosolic Ca2+ homeostasis are one of the conserved biochemical pathways regulating the response. Molecular targets for Ca2+ are now being identified and include signal transduction intermediates, endonuclease(s) and proteases, and the enzymes involved in the …

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Contact Force Dependence On Relative Humidity: Investigations Using Atomic Force Microscopy, E. Finot, E. Lesniewska, J. -C. Mutin, S. I. Hosain, J. -P. Goudonnet Aug 1996

Contact Force Dependence On Relative Humidity: Investigations Using Atomic Force Microscopy, E. Finot, E. Lesniewska, J. -C. Mutin, S. I. Hosain, J. -P. Goudonnet

Scanning Microscopy

This paper deals with the ability of scanning force microscopy to determine contact forces of various materials. Indeed, with high spring constants at low relative humidity, the nature of the material can be determined by measurement of the contact force as the tip approaches. Cantilevers with a high spring constant are used to achieve solid-solid contact for the tip-sample system. The capillary force estimation provides information on the development of the height of the water meniscus formed between the tip and different surfaces depending on the relative humidity. Finally, we focus our attention on measurements of moduli of elasticity which …

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Covalent Labeling Of Proteins With Fluorescent Compounds For Imaging Applications, Darl R. Swartz Aug 1996

Covalent Labeling Of Proteins With Fluorescent Compounds For Imaging Applications, Darl R. Swartz

Scanning Microscopy

The labeling of proteins with fluorescent compounds for microscopy has allowed a greater understanding of biological processes. The preparation of fluorescent proteins is the first step in development of their use in microscopy. Methods are described to label and characterize a protein as an example of the general approach for other proteins. Skeletal muscle alpha-actinin was labeled with either fluorescein-5-maleimide or 5-iodoaceamidofluorescein and the reaction characterized. The maleimide reaction was much more rapid and efficient than the iodoacetamide reaction giving a coupling efficiency of 65% under the given ration conditions. The fluorescein-5-maleimide alpha-actinin was functionally characterized and there was essentially …

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Labeling With Nanogold And Undecagold: Techniques And Results, James F. Hainfeld Aug 1996

Labeling With Nanogold And Undecagold: Techniques And Results, James F. Hainfeld

Scanning Microscopy

A significant new development in gold labeling for microscopy has been achieved through the use of gold cluster compounds that are covalently attached to antibodies or other probe molecules. These unique gold probes are smaller than most colloidal gold conjugates and exhibit improved penetration into tissues, higher labeling densities, and allow many new probes to be made with peptides, nucleic acids, lipids, drugs, and other molecules. A new fluorescent-gold conjugate is useful for examining localization by fluorescence microscopy, then visualizing the same label at the ultrastructural level in the electron microscope.

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Quantitative Analyses Of Microwear And Honing On The Sloping Crest Of The P3 In Female Japanese Monkeys (Macaca Fuscata), Teruyuki Hojo Aug 1996

Quantitative Analyses Of Microwear And Honing On The Sloping Crest Of The P3 In Female Japanese Monkeys (Macaca Fuscata), Teruyuki Hojo

Scanning Microscopy

Female wild Japanese monkeys (Macaca fuscata), as with all male cercopithecoids, use the mesiobuccal surfaces or the elongated crests of the mandibular third premolars (P3s), as cutting blocks that wear against edges of maxillary canines during threat manifestation or food-eating. In other words, the crests of their P3s are honed with the maxillary canines. The crests become sloped during growth and more heavily striated with the advance of age. The number, directions, lengths, and widths of these striations have been analyzed quantitatively using scanning electron microscopy (SEM). Two samples showed two distinct types of parallel striations, one longer and thicker …

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The Neonatal Chinchilla Cochlea: Morphological And Functional Study, R. V. Harrison, J. R. Cullen, S. Takeno, R. J. Mount Aug 1996

The Neonatal Chinchilla Cochlea: Morphological And Functional Study, R. V. Harrison, J. R. Cullen, S. Takeno, R. J. Mount

Scanning Microscopy

The developmental time scale of the cochlea varies from species to species. We investigate here the condition of the neonatal cochlea in the chinchilla, a species increasingly used in auditory research. We have examined the morphology of cochlear hair cells using scanning microscopy, and the development of auditory function during the first postnatal month by monitoring auditory brainstem evoked responses (ABR). We find that although there were some outer hair cell kinocilia present in middle and apical areas, the hair cells otherwise were mature at 24 hours after birth. Furthermore, cochlear auditory thresholds are adult-like at birth. However, whilst there …

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Cytoskeletal Changes During Radiation-Induced Neoplastic Transformation Of Human Prostate Epithelial Cells, S. C. Prasad, P. J. Thraves, J. S. Rhim, M. R. Kuettel Aug 1996

Cytoskeletal Changes During Radiation-Induced Neoplastic Transformation Of Human Prostate Epithelial Cells, S. C. Prasad, P. J. Thraves, J. S. Rhim, M. R. Kuettel

Scanning Microscopy

We recently reported tumorigenic transformation of SV 40-immortalized neonatal human prostate epithelial cells (267Bl) by exposure to fractionated doses of X-rays. Altered morphology and anchorage independence were observed following two successive fractions of 2 Gy each (F3-SAC). Additional 2 Gy treatments to these non-tumorigenic cells to a total dose of 30 Gy resulted in radiation-transformed tumorigenic colonies (267Bl-SXR). Malignant transformation of parental 267B 1 cells was also achieved by consecutive 2 Gy exposures to a total dose of 30 Gy (267Bl-XR). This study discusses the cytoskeletal changes in the F3-SAC, 267Bl-XR and 267Bl-SXR derivatives of these human prostate epithelial cells. …

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Advanced Instrumentation And Methodology Related To Cryoultramicrotomy: A Review, H. Sitte Aug 1996

Advanced Instrumentation And Methodology Related To Cryoultramicrotomy: A Review, H. Sitte

Scanning Microscopy

This review is concerned with the considerable progress in the field of cryo-ultramicrotomy (cryofixation, cryosectioning, investigation and analysis of cryosections) during recent years. This progress includes both more efficient instrumentation and methodology. The article is mainly directed to the investigation and analysis of frozen-hydrated sections in the low dose cryo-transmission electron microscopy (TEM) and cryo-energy filtered TEM (EFTEM). A general survey is followed by an evaluation of the different relevant procedures. Both cryo-ultramicrotomy for macromolecular cytochemistry (Tokuyasu technique) and cryo-ultramicrotomy for element analysis are only shortly mentioned without discussion of the chemical and analytical approach. Because of lack of first …

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Pre-Embedding Staining Of Single Muscle Fibers For Light And Electron Microscopy Studies Of Subcellular Organization, Evelyn Ralston, Thorkil Ploug Jul 1996

Pre-Embedding Staining Of Single Muscle Fibers For Light And Electron Microscopy Studies Of Subcellular Organization, Evelyn Ralston, Thorkil Ploug

Scanning Microscopy

Skeletal muscle fibers are large, multinucleated cells which pose a challenge to the morphologist. In the course of studies of the distribution of the glucose transporter GLUT4, in muscle, we have compared different preparative procedures, for both light (LM) and electron microscopy (EM) immunocytochemistry. Here we show that pre-embedding staining of single teased fibers, or of single enzymatically dissociated fibers, has several advantages over the use of sections for observing discrete patterns that extend over long distances in the cells. We report on an optimization study carried out to establish fixation and permeabilization conditions for EM immunogold labeling of the …

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