“Further Ultrastructure Observations of the Salamander Heart Maintained in Vitro”

1967 ◽  
Vol 25 ◽  
pp. 22-23
Author(s):  
Edward W. Millhouse
Keyword(s):  
Morphological Changes ◽  
Uranyl Acetate ◽  
Culture Period ◽  
Lead Citrate ◽  
Initial Report ◽  
Taricha Torosa ◽  
Cacodylate Buffer

Three years ago an initial report from our laboratory demonstrated the morphological changes observed in whole larval salamander (Taricha torosa) hearts maintained in culture for six months. Since then we have examined whole hearts that have been cultured from one to four months. During the culture period all hearts continued and maintained a particular beat with fluctuations in pulsation rates indicating a 24-hour periodicity.This report will deal with the ultrastructure observations of control hearts and one, two, three, and six month cultured hearts. All tissues were fixed initially from 4 to 6 hours at 4°C in 4%, redistilled glutaraldehyde buffered with cacodylate to a pH 7.4. Then the atrium was dissected free and the ventricle cut in half and, using fresh fixative, the fixation was continued for 10 hours. The tissues were washed in cacodylate buffer and stored in the cacodylate buffer containing 7% sucrose for 12 to 24 hours. These tissues were washed in buffer and post-fixed in 2% OsO4 buffered with cacodylate to pH 7.4 for two hours at 4°C. Then the tissues were dehydrated in graded ethanols, embedded in Epon 812, and sectioned on a Porter-Blum ultramicrotome. Sections were stained for 30 minutes in saturated aqueous uranyl acetate and for 15 minutes in lead citrate and viewed in an RCA EMU-3H.

Ultrastructure of E. coli: An in vitro study of cells cultured in the presence of four gastrointestinal (GI) hormones

1990 ◽  
Vol 48 (3) ◽  
pp. 628-629
Author(s):  
Leo J. Henz ◽  
Frank E. Johnson
Keyword(s):  
Morphological Changes ◽  
In Vitro Study ◽  
Uranyl Acetate ◽  
Culture Collection ◽  
En Bloc ◽  
Thin Sections ◽  
E Coli ◽  
Cacodylate Buffer ◽  
Synthetic Hormones

Hormones are found in exocrine secretions entering the gut. They alter the morphology of many eukaryotic cells; whether they affect the morphology of enteric flora is unknown. In this study, we examined the ultrastructure of E. coli, a common bacterium in the mammalian gut, for morphological changes resulting from exposure to GI hormones.E. coli (#11775 from American Type Culture Collection) were grown in protease-free trypticase soy broth (TSB) at 37°C for 18 hr to a concentration of 2 x 107 cells/ml. Pure synthetic hormones were used: sulfated C-terminal cholecystokinin octapeptide (CCK), pentagastrin (PG), cyclic somatostatin tetradecapeptide (SS), or the porcine form of secretin (SEC). These were individually added to. bacterial cultures in TSB to make 1 x 107 organisms/ml and 0.0, 0.5, 2.5, or 5.0 μg of hormone/ml, then incubated for 30 min at 37°C. The cultures were rapidly chilled and added to equal volumes of cold 6% glutaraldehyde in 0.2 M cacodylate buffer. After 30 min, the bacteria were concentrated by centrifugation (15 min at 4000 RPM) and the pellets suspended in cold 3% glutaraldehyde for an additional 15 min, followed by centrifugation. The pellets were resuspended in cold cacodylate buffer and stored at 2°C for 1-7 d. The cells were again centrifuged and the pellets were blotted with a strip of filter paper to remove excess fluid, then mixed with a drop of warm 2% agar. The agar suspensions were pipetted into cold saline. The resulting solidified extrusions were cut by hand into 2 mm segments for further processing in 1% OsO4 (with or without en bloc staining in 2% uranyl acetate (UA) in ethanol). Following dehydration in ethanol, rinsing in propylene oxide, and encapsulation in Epon-Araldite, thin sections were examined and photographed with a JEOL-100C microscope.

Ultrastructural Observations on Microspore Development in Rice Anther Culture

1985 ◽  
Vol 43 ◽  
pp. 646-647
Author(s):  
S. S. Ren ◽  
J. C. Chen ◽  
Y. R. Chen
Keyword(s):  
Anther Culture ◽  
Oryza Sativa L ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Microspore Development ◽  
Thin Sections ◽  
Cacodylate Buffer ◽  
Fine Structures ◽  
Development In Vitro

The plants produced from rice anther culture varied in ploidy level. Genetic analysis of anther-derived plants indicated genome multiplication occurred in microspore development in vitro. Cytological studies on early roicrospore division suggested endoreduplication and nuclear fusion may be related to the production of nonhaploid plants. In the present study, fine structures of callus ontogeny in anther culture were emphasized.Anthers of rice(Oryza sativa L. c. v. Hsinchu 4, 2n=24) containing mid-uninucleate microspores were excised and cultured in Ng liquid medium, supplimented with 60 g/l sucrose, 1 mg/l kinetin and 2 mg/l naphthalenacetic acid. Cultured anthers were collected at 2 days intervals for 20 days and fixed in 2.5% glutaraldehyde in 0.1M cacodylate buffer(pH=7.0), postfixed in osmium tetraoxide, and then embedded in Spurr's resin. Thin sections were stained with uranyl acetate and lead citrate, observed under Hitachi H-600 at 75 KV.

Gap junction associated filaments in testis interstitial cells of the rat

1978 ◽  
Vol 36 (2) ◽  
pp. 550-551
Author(s):  
J.F. David-Ferreira ◽  
K.L. David-Ferreira ◽  
M.H. Miranda ◽  
J.C. Lemos
Keyword(s):  
Gap Junction ◽  
Freeze Fracture ◽  
Interstitial Cells ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Thin Sections ◽  
Cacodylate Buffer ◽  
Old Rats ◽  
The Relationship ◽  
Made In

The testis interstitial cells of the rat are closely associated forming small aggregates in the vicinity of the vessels. The finality of the present study is to analise the relationship between the interstitial cells and to describe some particularities of their junctions.The observations were made in thin sections from testis of 2 to 3 months old rats fixed by immersion or perfusion with 2 to 3% glutaral- dehyde in s-collidine or cacodylate buffer followed by 2% osmium tetro-xyde in the same buffers. Some specimens have been prepared following the technique of Shea. The thin sections obtained after embedding in Epon were double stained in uranyl acetate and lead citrate. For the cryofracture study the tissues were fixed in 3% glutaraldehyde in cacodylate buffer, impregnated in 28% glycerol, frozen in Freon 22 and stored in liquid nitrogen. Freeze fracture and platinum-carbon shadowing were done in a Balzers 300.

MORPHOLOGICAL CHANGES OF BLOOD PLATELETS IN MAN DURING DEEP SATURATION DIVING

1987 ◽  
Author(s):  
Hanne Klausen ◽  
Per Flood ◽  
John O Hjelle ◽  
Holm Holmsen
Keyword(s):  
Morphological Changes ◽  
Blood Platelets ◽  
Venous Blood ◽  
Gas Bubbles ◽  
En Bloc ◽  
Deep Diving ◽  
Transmission Electron ◽  
Cacodylate Buffer ◽  
High Incidence

The small number of reports concerning blood platelets during deep saturation diving have shown that there may be a decrease in the number of circulating platelets. Gas bubbles are often present in theblood during decompression. In vitro, gas bubbles activate platelets, and alter the shape from discoidto spherical configuration with multiple, blunt spikes. This study was done to investigate if there are changes in the morphology of human blood platelets during deep diving. An 18 day long experimentalon-shore saturation dive to 360 msw was performed at NUTEC 1986. Bloodsamples were obtained from the 6 divers on 6 occations: pre-dive control, at 360 msw, 300 msw, 140 msw, 1 and 3 days after surfacing. Using 18 G Wasserman needles antecubital venous blood samples (3ml) were collected directly into the fixative agent (7 ml of 2% glutardialdehyde in cacodylate buffer) whilestill in the hyperbaric chamber. The samples were then decompressed,and the platelets separated from the blood by centrifugation at roomtemperature for 10 min at 190 g. Preparation to transmission electron microscopy included post-fixation in osmium tetroxide, staining uranyl-en-bloc and eventually lead, dehydration and embedding in Epon.Ultrathin sections were examined by a Philips 300 I electron microscope. The examination revealed alterations in both platelet size and shape in the course of the dive. The mean platelet area was increased during and immidiately after thedive, the greatest increase occuring at 360 msw. There was a high incidence of shape changed plateletswith spherical configuration and multiple, blunt spikes. This form was by far most abundant at 360 msw, and the morphology normalised towards surface. This rises the suspection of a pressure-related rather rhan bubble-related effect and the results indicate that plateletsin circulation can be activated bypressure itself

Ultrastructure of the Synovial Microvasculature in Rheumatoid Arthritis (ra) and Systemic Lupus Erythematosus (SLE)

1970 ◽  
Vol 28 ◽  
pp. 240-241
Author(s):  
H. Ralph Schumacher
Keyword(s):  
Lupus Erythematosus ◽  
Uranyl Acetate ◽  
Basement Membranes ◽  
Ultrastructural Changes ◽  
Lead Citrate ◽  
Vascular Changes ◽  
Systemic Lupus ◽  
Degenerative Arthritis ◽  
Cacodylate Buffer ◽  
Human Joint

Synovial vascular alterations have been suggested to be important in the pathogenesis of both RA and SLE (1). Although vascular changes have been described by light microscopy the presence of significant ultrastructural changes has been questioned (2). This report describes an EM study of needle synovial biopsies from 5 patients each with classical RA and SLE. Specimens were promptly fixed in Karnovsky's paraformaldehyde-glutaraldehyde diluted 1:1 with 0.1 M cacodylate buffer at pH 7.4, washed in buffer, post-fixed in Palade's osmium-veronal, dehydrated with alcohol, embedded in epon, cut, and stained with lead citrate and uranyl acetate. Vascular changes were seen in both groups with some findings common to both diseases. Basement membranes were multilaminated. (Fig.l). This was not seen in normal rabbits and monkeys but was also present in other human joint diseases including degenerative arthritis. Venular endothelium was active appearing with filopodia extending into the lumen and with gaps demonstrable between endothelial cells (Fig.2,3). Platelets occluded some gaps (Fig.2).

Bacterioids in the Rectal Organ of the Lantern Dug Pyrops Candelaria Linn (Homoptera: Fulgoridae)

1996 ◽  
Vol 54 ◽  
pp. 806-807
Author(s):  
W.W.K. Cheung ◽  
J.B. Wang
Keyword(s):  
Fine Structure ◽  
Electron Microscope ◽  
Osmium Tetroxide ◽  
Uranyl Acetate ◽  
Sodium Cacodylate Buffer ◽  
Lead Citrate ◽  
Sodium Cacodylate ◽  
Special Pair ◽  
Adult Females ◽  
Cacodylate Buffer

The lantern bug harbours three symbionts, namely a, x and i in its body. These microorganisms are supposed to be transmitted transovarially to the future progeny. The x-symbionts are found in a special pair of organs called the x-organ which bulges to form a rectal organ in adult females. The purpose of this study is to investigate into the fine structure of the x-symbionts. This will serve as a basis for understanding the interactions of this microorganism with its host.The rectum of the lantern bug Pyrops candelaria Linn, was dissected out in buffered insect saline and fixed in 2.5% glutaradehyde in 0.1M sodium cacodylate buffer (pH 7.2) for 1 hr. The rectal organ was subsequently post-fixed in 1% osmium tetroxide (pH 7.2) and dehydrated in alcohol/acetone series. These were blocked in Spurr resin and cut with a Reichert Ultratome. Sections were stained with uranyl acetate and lead citrate and examined with a JEOL JEM-1200EX electron microscope. Thick sections (1 μn) were stained with 1% toluidine blue and examined under a Nikon Optiphot light microscope.

Ultrastructural Study of Trophozoites and Cysts of Acanthamoeba-Hartmannella and Naegleria Species

1974 ◽  
Vol 32 ◽  
pp. 192-193
Author(s):  
A. Julio Martinez ◽  
Richard J. Duma ◽  
Doris G. Fultz ◽  
Ruth B. Finley
Keyword(s):  
Present Report ◽  
Uranyl Acetate ◽  
Osmic Acid ◽  
Acetate Solution ◽  
Lead Citrate ◽  
Thin Sections ◽  
Cacodylate Buffer ◽  
In Situ Fixation ◽  
Diamond Knife

Ultrastructural components of trophozoites and cysts of Acanthamoeba-Hartmannella (A-H) and Naegleria amebas have been investigated. The present report describes a technique to study the morphological features of such protozoa.The A-H strains selected were cultured for 7 days in axenic amebic media, and the Naegleria strains were cultured for 7 days in axenic media with blood. In situ fixation was accomplished by adding an equal volume of 4% Osmic Acid in Cacodylate buffer at 4¶C for one hour. Following frequent agitation, the tubes were then spun at 2500 RPM for 10 minutes to obtain a pellet. The pellets were dehydrated in graded series of alcohols (from 50% to absolute) and propylene oxide and then embedded in EPON. One micron sections were stained with Paragon (PS 1301) for thirty seconds. Thin sections were cut with a diamond knife, double stained with 5% alcoholic uranyl acetate solution and lead citrate and observed in an Hitachi-HS-8F2 electron microscope.

Banded Structure in a Hepatocellular Carcinoma

1977 ◽  
Vol 35 ◽  
pp. 510-511
Author(s):  
E. C. Chew ◽  
W. C. Chan
Keyword(s):  
Electron Microscopy ◽  
Hepatocellular Carcinoma ◽  
Osmium Tetroxide ◽  
Periodic Acid ◽  
Uranyl Acetate ◽  
Lead Citrate ◽  
Periodic Acid Schiff ◽  
Cacodylate Buffer ◽  
Tissue Area ◽  
Neural Tumor

Extracellular banded structures were first reported by Luse (1) in a neural tumor and subsequently by others in many types of tissues. This subject was summerized in detail by Sun and White in 1975 (2). This communication reports observations of banded structures discovered by electron microscopy in the study of a human hepatocellular carcinoma. The tissue was fixed in 3% glutaraldehyde in 0.1 M cacodylate buffer and post-fixed in buffered osmium tetroxide. Sections were stained with uranyl acetate and lead citrate. Thick sections, about 1 - 2 μ, were stained with periodic acid-Schiff's reagent involving heating of the slides.Banded structures are observed in the connective tissue area intermingled with collagen fibrils and are usually fusiform in shape (Fig. 1). The fusiform bodies average 0.5 μ in diameter and are outlined with periodicity of 800 to 1000 A°. Each period consists of a light and a dark band. Fine filaments of about 24 A° in thickness are present in the light bands (Fig. 2). They are also found to be periodic acid-Schiff positive (Fig. 3).

The Role of the Internal Coating in the Ultrastructural Architecture of Pinocytic Vesicles and its Significance in Vesicular Transport

1971 ◽  
Vol 29 ◽  
pp. 398-399
Author(s):  
T. Shirahama ◽  
A. S. Cohen ◽  
O. G. Rodgers
Keyword(s):  
Body Weight ◽  
Uranyl Acetate ◽  
Ruthenium Red ◽  
Lead Citrate ◽  
Healthy Young Adult ◽  
Thin Sections ◽  
Cacodylate Buffer ◽  
New Zealand White Rabbits ◽  
Pinocytic Vesicles

Forty-micron nonfrozen sections of myocardium from several healthy young adult New Zealand white rabbits, without pretreatment or 10-15 minutes after an intravenous ferritin injection (100 mg ferritin/100 gm. body weight), were double fixed with 2% formaldehyde - 2.5% glutaraldehyde in 0.1M cacodylate buffer and 2% OSO4 in 0.1M cacodylate buffer in the presence of 1000, 100, 50 or 20 ppm ruthenium red (RR), and embedded in Epon. Thin sections of small blood vessels including capillaries, unstained or stained with uranyl acetate and/or lead citrate, were photographed at initial magnifications of 40,000 or 80,000. The results were analysed to delineate the ultrastructural relation of mucopolysaccharides (MPS) in the architecture of pinocytic vesicles and the MPS role in pinocytosis.

Fine structure of human sperm entry into zona-free hamster oocyte

1978 ◽  
Vol 36 (2) ◽  
pp. 540-541
Author(s):  
C. Barros ◽  
J. González ◽  
E. Herrera ◽  
E. Bustos-Obregón
Keyword(s):  
Osmium Tetroxide ◽  
Human Sperm ◽  
Ultrastructural Level ◽  
Uranyl Acetate ◽  
Human Spermatozoa ◽  
Low Viscosity ◽  
Cacodylate Buffer ◽  
Ultrathin Sections ◽  
Hamster Oocyte

Zona-free mammalian oocytes have been observed to fuse, under in vitro conditions, With non-homologous spermatozoa. Taking advantage of this heterologous gamete fusion, we designed a bioassay to test -by means of zona-free hamster oocytes- the fertile ability of human spermatozoa, from semen samples of patients attending an Infertility Clinic. To further validate our bioassay, which Was reported elsewhere, we studied the behavior of gamete membranes during fusion at the ultrastructural level.Zona-free hamster oocytes were mixed in vitro with human spermatozoa. At different times after the start of incubation, oocytes were fixed in 1% glutaraldehyde in 0. 25M cacodylate buffer pH 7. A and post-fixed in 196 osmium tetroxide. After dehydration in acetone, they were embedded in a low viscosity epoxy resin. Ultrathin sections were stained with uranyl acetate and lead citrate and examined with a Phillips 300 electron microscope.

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