Biology Commons^™

Ultrastructural Effects Of Lead Acetate On The Spleen Of Rats, Mesure Türkay, Hüseyi̇n Türker, Turan Güven

Turkish Journal of Biology

In this experiment, the ultrastructural effects of orally administered lead acetate on rat (Rattus rattus) spleen were studied. Rats weighing approximately 200-250 g were used in this experiment. They were divided into five groups, each one including five rats. Group I served as the normal control group while the others served as the experimental groups. The rats were exposed to oral administrations of lead acetate of 2.5 mg dissolved in 1 mL of drinking water per day. The administration lasted 96, 144, 336, and 432 h. The animals were anesthetized using chloroform inhalation and the peritoneum was stripped open and …

L-Arginine Protects Against Ethylene Glycol-Induced Gastric Mucosal Damage In Rats: Immunohistochemical And Electron Microscopic Study, Samah Kandeel, Thoryaa El_Deeb, Ehsan Salah, Nafisa El-Bakary, Naglaa Sarhan, Mohamed Balaha, Hiroki Sakai, Tokuma Yanai

Turkish Journal of Biology

Ethylene glycol is an alcohol widely used in industry as an antifreeze. It affects the normal gastric mucosal defense mechanisms, inducing surface ulcerations. L-arginine is a precursor of nitric oxide that exhibits multiple biological properties; among them is the acceleration of wound healing, especially in the stomach. Caspase-3 immunohistochemistry, and semithin and ultrathin section examinations were used to investigate the possible protective effect of L-arginine on ethylene glycol-induced gastric mucosal damage in rats. Three animal groups were used: group A (control group), group B (received 3.3 mL/kg ethylene glycol for 2 weeks), and group C (received 200 mg/kg of L-arginine …

The Effects Of Uv Radiation On Some Structural And Ultrastructural Parameters In Pepper (Capsicum Longum A.Dc.), Siavash Hosseini Sarghein, Jirair Carapetian, Jalil Khara

Turkish Journal of Biology

The objective of this study was to evaluate the effects on the structure and ultrastructure of pepper plants (Capsicum longum A.DC.) exposed to UV radiation under greenhouse conditions. The plants were grown in a growth chamber under uniform environmental conditions and after 35 days were exposed to UV-A and UV-C radiation for 15 and 8 days, respectively. Changes in root growth were not significant, but shoot growth decreased in UV-R-exposed plants and decreased significantly in UV-C-exposed plants. Leaf area also decreased in UV-R-exposed plants and decreased significantly in UV-C-exposed plants. Root thickness was not affected by UV treatment, but stem …

Ultrastructural Changes In Rat Liver By Methyleugenol And Evaluation Of Some Biochemical Parameters, Ayşegül Çerkezkayabeki̇r, Gülnur Kizilay, Fi̇gen Ertan

Turkish Journal of Biology

The present study investigated the effect of methyleugenol, a food flavoring and fragrance agent, on the livers of laboratory rats. Doses of 10 and 30 mg/kg/day of methyleugenol (in 0.5% methylcellulose) were administered intragastrically (IG) to 2 dose groups for 10 days alongside a control group (n = 10 for each group). Gains in body weight were not statistically significant for either dose. Lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) activities decreased (P < 0.05) for both dose groups, but AST (aspartate aminotransferase) activity decreased significantly (P < 0.05) only in the 30 mg/kg/day methyleugenol dose group. Alanine aminotransferase (ALT) activity did not change significantly in either group. The total amount of glucose remained unchanged, but glycogen in the liver decreased significantly (P < 0.05) in the 30 mg/kg/day methyleugenol dose group. There was also an increase of swelling in the smooth endoplasmic reticulum sacs (sER), electron dense accumulations in the sER, cytoplasmic vacuolization, a slight increase of mitochondria and lysosomes, and invaginations in the nucleus membranes of hepatocytes. Extensions in bile canaliculi and increasing microvilli of bile canaliculi in the liver were also observed. These findings indicate the ultrastructural toxic effect of methyleugenol on rat livers in 10 and 30 mg/kg/day doses. Therefore, we may speculate that the toxic effect of methyleugenol needs to be examined in detail.

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, …

The Interaction Of Laser Energy With Ureter Tissues In A Long Term Investigation, U. Stratmann, K. Schaarschmidt, R. R. Lehmann, A. Heinze, G. H. Willital, E. Unsold

Scanning Microscopy

This study investigates tissue responses after laser irradiation of the rabbit ureter, which serves as an experimental model for rectourogenital fistulae of children. Twenty-five rabbit ureters were irradiated intraluminally by a Nd:YAG laser 1320 nm (2 Watt, 20 seconds and 3 Watt, 8 seconds) via an applicator with radialsymmetrical light distribution. Immediately, 2 weeks, 4 weeks, 8 weeks, and 16 weeks after irradiation, the ureters were X-rayed with contrast solution and prepared for light and transmission electron microscopy. For the parameters employed, no apparent morphological differences could be observed. Immediately, the central laser zone showed a transmural therrnonecrosis prevailed by …

Cell Surface Changes Of Hemopoietic Cells During Normal And Leukemic Differentiation: An Immuno-Scanning Electron Microscopy Study, D. Soligo, E. P. De Harven, N. Quirici, L. Caneva, G. Lambertenghi Deliliers

Scanning Microscopy

Hemopoietic cells display a wide range of cell surface antigens which are either lineage specific or acquired during differentiation. Monoclonal antibodies can be used, in conjunction with colloidal gold markers, to identify under the scanning electron microscopy (SEM) at the single cell level, specific lineage or maturation stages in the hemopoietic bone marrow. Normal bone marrow cells, either gradient separated or purified by immuno-magnetic methods and leukemic cell samples, which can be considered as "frozen" stages of hemopoietic differentiation, have been studied with this method. Typical cell surface morphologies, which characterize immature progenitor cells and cells committed or differentiated towards …

Notes On The Microstructure Of The Nautilus Shell, P. R. Mitchell, P. P. Phakey

Scanning Microscopy

The shell of the Nautilus was examined using scanning electron microscopy, transmission electron microscopy and polarized light microscopy. The structure consisted of two major layers: a porcellaneous outer layer and a nacreous inner layer. Most of the porcellaneous layer was composed of granular crystals randomly distributed with a substructure suggestive of bundles of acicular crystallites. A separate prismatic sublayer of the porcellaneous material was composed of a more regular arrangement of crystals. The nacre was composed of alternating crystalline lamellae and films of organic material. The lamellae were formed of many polygonal crystal platelets. The growth surface of the nacre …

Scanning Electron Microscopy And Transmission Electron Microscopy Aspects Of Synergistic Antitumor Activity Of Vitamin C - Vitamin K3 Combinations Against Human Prostatic Carcinoma Cells, Jacques Gilloteaux, James M. Jamison, Meenaxi Venugopal, David Giammar, Jack L. Summers

Scanning Microscopy

A MTT/formazan assay was used to evaluate the antitumor activity of vitamin C (Vit C), vitamin K₃ (Vit K₃), or vitamin C:vitamin K₃ combinations against a human prostatic carcinoma cell line (DU145). Both Vit C and Vit K₃ alone exhibited antitumor activity, but only at elevated doses. When Vit C and Vit K3 were combined at a C:K₃ ratio of 100:1 and administered to the carcinoma cells, the 50% cytotoxic concentrations (CD50) of the vitamins decreased 10-to 60-fold. Subsequently, the DU145 cells were examined with transmission and scanning electron microscopy (TEM and SEM) following …

Time-Resolved Cryofixation Methods For The Study Of Dynamic Cellular Events By Electron Microscopy: A Review, Keith P. Ryan, Gerd Knoll

Scanning Microscopy

The preservation of cells for electron microscopy by chemical fixation is a lengthy process, requiring up to 30 minutes for cytoplasmic stabilisation. This time lag enables many changes to occur in specimens so that they may not reflect their living state when they are observed in electron microscopes. Many artefacts can be avoided by using cryofixation, which freezes specimens over a period that is measured in milliseconds, so that specimens are preserved by cryoimmobilisation. This time resolution can be used to study rapid processes in biology and chemistry because, although electron microscopes cannot observe dynamic cellular events directly, processes can …

Ultrastructural Features Of Apoptosis, Elisabetta Falcieri, Pietro Gobbi, Loris Zamai, Marco Vitale

Scanning Microscopy

Apoptosis is a gene-directed physiological and programmed process of cell deletion aimed at the regulation of tissue and organ development. It affects different cell types and is triggered by a variety of stimuli all inducing closely comparable structural changes. Despite the deeply different morphology and metabolism of the cell models and the various inducers and their initial effects, a convergence seems to take place in a common metabolic pathway that, in most cases, involves the activation of a Ca²⁺ dependent endonuclease. A growing body of data is now available on the molecular events that lead to DNA damage. DNA …

Ultrastructural Observations Of The Argonaut Shell, P. R. Mitchell, P. P. Phakey, W. A. Rachinger

Scanning Microscopy

An examination of the ultrastructure of the shell of the cephalopod Argonauta Nodosa was carried out using scanning electron microscopy, transmission electron microscopy and polarised light microscopy. The structure of the Argonaut shell was found to consist of an inner and outer prismatic layer separated by a thin central zone which was sparsely occupied by spherulitic crystals. Fluctuations in the width and porosity of the central zone resulted in changes in the shell's opacity and gave rise to the fibrous lines visible in the structure. The central zone was the region of initial growth and was the nucleating point for …

The Vascularization Of The Kidney Of The Eel (Anguilla Anguilla - Osteichthyes) In The Freshwater Habitat, Hans Ditrich, Heinz Splechtna

Scanning Microscopy

The renal vascular system of eels (Anguilla anguilla L.) in freshwater has been investigated using light-, transmission electron-, and scanning electron microscopy of vascular corrosion casts and critical-point dried specimens. The morphology of the kidney exhibits a highly evolved, unpaired, spindle-shaped form. The renal tissue extends partially into a recessus dorso-caudal to the anus. Renal glomeruli are comparatively large (100.8 μm +/-17 standard deviation) and well vascularized. They are arranged in grape-like clusters around the intrarenal arteries. Closely neighbouring glomeruli can be surrounded by incompletely separated Bowman's capsules sharing the same renal tubule. The peritubular capillary plexus is …

Ultrastructural Features Of Human Reissner's Membrane, Anne De Fraissinette, Heidi Felix, Jannie Nievergelt, Michael Gleeson

Scanning Microscopy

Ultrastructural features of human Reissner' s membrane were investigated in two groups of similarly aged patients. Five patients had age-related normal hearing (ARNH) and four patients had acquired sensorineural hearing loss (SNHL) from causes other than age. The membrane consisted of a mesothelium facing the perilymph and an epithelium facing the endolymph. The two cell layers were separated by a basement membrane. The mesothelium was formed by wide spread thin cells with a smooth surface. The epithelial cells assumed two different shapes, flat and rounded. Both epithelial cell types were covered with many short microvilli. In all specimens, the rounded …

The Use Of Sonic Frequencies As A Cleaning Agent Of Specimens To Be Observed By Scanning Electron Microscopy, G. Familiari, A. Familiari, G. Macchiarelli, L. J. A. Didio, P. M. Motta

Scanning Microscopy

The presence of mucus and/or cellular debris can obscure the fine morphology of the gastrointestinal or respiratory luminal surface, when observed by scanning electron microscopy. With the intent of obtaining a good cleaning of the mucosal surface without altering the ultrafine morphology of epithelial cells, a new model of sonicator/ultrasonicator is presented.

The instrument is supplied with a control system for wave frequency, amplitude and form, and permits a precise regulation of the wave energy. With this instrument it is possible to produce a "cleaning effect" by using any kind of frequency (either sonic or ultrasonic) and/or amplitude and/or waveform …

Ultrastructural Effects Of Therapeutic Irradiation On Human Epithelial Tumors, P. Kellokumpu-Lehtinen

Scanning Microscopy

Irradiation induces several cellular changes leading to death of cancer cells and normal cells which is followed by repairing processes of normal cells. We have studied the effects of therapeutic irradiation on head and neck cancers. Tissue samples taken before and during the radical irradiation (50-80 Gy) of the squamous cell carcinomas of the head and neck region were examined by light and electron microscopy. Nuclear atypia was most pronounced cellular change during irradiation. The tumor invasion pattern remained unchanged but the number of mitoses decreased. Lymphocytic infiltration increased at the beginning of the therapy (from 10 to 30 Gy) …

The Normal, Cryptorchid And Retractile Prepuberal Human Testis: A Comparative Morphometric Ultrastructural Study Of 101 Cases, Saverio Cinti, Giorgio Barbatelli, Claudia Pierleoni, Manlio Caucci

Scanning Microscopy

Fifty-two surgical biopsies from retractile testes of patients in pediatric age (3-14 years), of which 25 were treated with hormonal therapy (RT) and 27 did not undergo therapy before orchidopexy (RNT), were compared with the biopsies of 19 normal (N) and 30 cryptorchid or ectopic (E) testes. A light and electron microscopic morphologic and morphometric study was performed. For the quantitative investigation 4 parameters were selected: a) the mean tubular diameter (on 20 cross-sections); b) the mean spermatogonial number per tubular section; c) the mean nucleolar area of the Sertoli cells; and d) the mean thickness …

The Splenic Microvasculature Of The Red-Eared Turtle (Chrysemys Scripta Elegans): A Study Concerning The Question Whether The Circulation Is Anatomically Open Or Closed, R. Blumer, H. Ditrich, H. Splechtna

Scanning Microscopy

The splenic microvasculature of the turtle Chrysemys scripta elegans was studied by means of scanning electron microscopy of vascular corrosion casts and critical point dried tissue. In addition light- and transmission electron microscopic investigations were carried out. Within the organ the arteries are surrounded by periarterial lymphoid sheaths. The majority of the arterial capillaries, which emerge from these central arteries have open endings within the reticular meshwork of the red pulp. Approximately 10% of the capillaries directly connect with the venous origins. Since these venous capillaries of C. scripta elegans resemble those of nonsinusal mammalian spleens we termed them pulp …

The Effect On The Ultrastructure Of Dental Enamel Of Excimer-Dye, Argon-Ion And Co2 Lasers, J. Palamara, P. P. Phakey, H. J. Orams, W. A. Rachinger

Scanning Microscopy

This study aimed to investigate the ultrastructural changes that occur in dental enamel irradiated with pulsed excimer-dye, continuous-wave (CW) argon-ion and CW CO2 lasers. The pulsed excimer-dye laser produced deep craters, rough damaged surfaces with underlying porosity and amorphous vitrified material. The vitrification of the enamel indicated that the temperature in these areas must have been al least in the range 1280 to 1600°C. The CW argon-ion laser irradiation produced a changed non-cratered surface with inter-crystalline porosity and a mixture of small and some large irregularly packed recrystallized enamel crystals. The CW CO2 laser produced shallow craters, surface crazing and …

Effects Of Modulated And Continuous Microwave Irradiation On The Morphology And Cell Surface Negative Charge Of 3t3 Fibroblasts, Z. Somosy, G. Thuróczy, T. Kubasova, J. Kovács, L. D. Szabó

Scanning Microscopy

Mouse embryo 3T3 cells were irradiated with 2450 MHz continuous and low frequency (16 Hz) square modulated waves of absorbed energy ranging from 0.0024 to 2.4 mW/g. The low frequency modulated microwave irradiation yielded more morphological cell changes than did the continuous microwave fields of the same intensity. The amount of free negative charges (cationized ferritin binding) on cell surfaces decreased following irradiation by modulated waves but remained unchanged under the effect of a continuous field of the same dose. Modulated waves of 0.024 mW/g dose increased the ruffling activity of the cells, and caused ultrastructural alteration in the cytoplasm. …

Ultrastructure Of Coronary Arterial Endothelium In Atherosclerotic Swine Suggests Lipid Retro-Endocytosis, Keith A. Robinson, Robert P. Apkarian

Scanning Microscopy

During experimental atherosclerosis, arterial endothelial cells show characteristic ultrastructural changes including the appearance of increased numbers of plasmalemmal and cytoplasmic vesicles. These structures have been shown by tracer studies to participate in the transcellular transport of low-density lipoprotein cholesterol and β-very-low-density lipoprotein cholesterol from the arterial lumen into the abluminal extracellular matrix. Although this probably represents the major lipid transport pathway, other forms of transport may exist. We document the presence of apparent lipid structures averaging approximately 300 nm in diameter at or near the luminal surface of coronary arterial endothelium of atherosclerotic miniature swine. The structures exhibited a particulate …

Alpha-Particle Irradiation-Induced Change In Bronchopulmonary Macrophage Morphology, In Vitro, T. M. Seed, G. K. Niiro

Scanning Microscopy

Bronchopulmonary macrophages, isolated from canine lungs by saline lavage and grown in tissue culture for short periods, were acutely irradiated with a range of doses of either Americium-241 alpha particles (0.03-48 Gy) or 250 keV x-rays (0.5-24 Gy). Following a 24-hour reincubation and "expression" period, cells were examined for radiation-induced changes in overall viability, as well as in cell morphology and ultrastructure. Results indicated that neither quality of radiation had much effect on cell viability over dose ranges examined, but substantial changes in cell volume, surface topography, and cytoplasmic features were noted, especially in the alpha-particle-irradiated specimens. Results support the …

Ultrastructural Effects Of Ionizing Radiation On Plant Cells, Á. Keresztes, E. Kovács

Scanning Microscopy

Ultrastructural effects of ionizing irradiation were investigated on the specific constituents of plant cells, primarily in fruits, with reference to mushroom cells and comparable data in the literature. In the cell wall the dissolution of the middle lamellae, probably due to radiation damage of pectin, and irregular thickenings were found. In the vacuole the quantity of inclusions changed, or unusual aggregations appeared, presumably in connection with altered phenolic biosynthesis . In chloroplasts the senescence was inhibited, and dedifferentiation occurred into agranal state. In amyloplasts starch hydrolysis was hind ere d. These platidial effects are considered as visible signs of inhibition …

Scanning Electron Microscope Study Of Wohlfahrtia Magnifica (Schiner, 1862) (Diptera: Sarcophagidae) I. Structures With Parasitic And Possible Taxonomic Meaning, I. Ruíz-Martínez, M. D. Soler-Cruz, R. Benítez-Rodríguez, J. M. Pérez-Jiménez, C. Adalid-Fuentes, M. Díaz-López

Scanning Microscopy

The larval development of Wohlfahrtia magnifica (the most important dipteran causing sheep myiasis in the Palearctic region) has been studied by means of scanning electron microscopy. The ultrastructure of mouth-hooks, oral ridges, labial lobes, body spines and anterior and posterior peritremes is described for the first time. Their possible adaptations to a parasitic lifeway are also discussed. Thus, the use of new structures in the Sarcophagidae taxonomy is proposed from the point of view of their ultrastructure and adaptative morphology.

The Vascular System Of Xenotransplanted Tumors -Scanning Electron And Light Microscopic Studies-, M. A. Konerding, F. Steinberg, V. Budach

Scanning Microscopy

A widely used model for investigating basic tumor characteristics and different treatment modalities preclinically is the immune-deficient, athymic nude mouse. This model offers many morphological parallelisms to the clinical situation.

The aim of this study is to demonstrate the vascularization pattern of xenotransplanted human melanomas and sarcomas using different methods. Xenotransplanted tumors of 62 congenital thymusaplastic nude mice were examined ultrastructurally and topographically after corrosion cast and tissue preparation. Quantitative measurements of tumors injected with India ink were carried out to obtain comparable information on the vascular densities in the tumors.

Quantitative measurements showed that there is no zonal, topographic …

Ultrastructural And Functional Effects Of Lipopolysaccharide And Interleukin-2 On Human Nk Cells, Yuan-Hsu Kang, Mitchell Carl, Lorrita P. Watson

Scanning Microscopy

Bacterial endotoxin (lipopolysaccharide, LPS) and interleukin-2 (IL-2) are known to stimulate NK cell mediated cytotoxicity against tumor cells. In the present report we sought to correlate the stimulatory effect of LPS and IL-2 on NK cell activity with ultrastructural changes which occurred as a result of such stimulation. Peripheral blood mononuclear cells (PBMC) were purified from healthy donors by a Ficoll-Hypaque density gradient technique. Leu-11a⁺ NK cells were isolated by flow microfluorometry using a monoclonal FITC conjugated anti-Leu-11a antibody and a FACS II cell sorter. The PBMC were incubated, respectively, with E. coli LPS or recombinant IL-2 (IL-2) for …

Scanning Electron Microscopy Of The Spermatheca Of Plethodon Larselli (Amphibia: Plethodontidae): Changes In The Surface Morphology Of The Spermathecal Tubule Prior To Ovulation, Christine M. Davitt, John H. Larsen Jr.

Scanning Microscopy

Spermathecae from eight mature female Larch Mountain salamanders (Plethodon larselli) were used to study cellular changes accompanying the administration of ovulation-inducing pregnant mare serum gonadotropin (PMSG). Animals injected daily with 25 IU of PMSG were sacrificed on day 2 or day 4. Ultrastructural alterations of the spermathecal tubules include an increase in the synthesis and release of product into the lumen and hypertrophy of two epithelial cell types by day 4. One cell type exhibits apocrine blebs and is covered with microvilli; the other contains large spherical vesicles and has only a few, short microvilli on its surface. These changes …

Scanning Electron Microscopy Of Black Stain On Human Permanent Teeth, J. Theilade, K. M. Pang

Scanning Microscopy

Black stain may develop on the coronal surfaces of human teeth, and this type of stain is common in the Hong Kong Chinese population. The present study was undertaken to ascertain if the deposit conforms in composition to the black stain found elsewhere, and to describe its ultrastructure using the scanning electron microscope. Gram-stained smears were made from black stain on the teeth of 11 adult Hong Kong Chinese and studied microscopically. From another 15 persons extracted teeth exhibiting black stain were obtained and fixed. Two ground sections were made from each tooth, one was stained with toluidine blue, the …

Ultrastructure Of Spermatozoa From Domesticated Birds: Comparative Study Of Turkey, Chicken And Guinea Fowl, R. J. Thurston, R. A. Hess

Scanning Microscopy

Typical for non-passerine birds, the spermatozoa of the turkey, chicken and guinea fowl were vermiform with a maximum width of 0.5-0. 7μm and lengths of 90μm for chicken sperm, and 75-80μm for those of the turkey and guinea. An acrosome, nucleus, midpiece and flagellum could be distinguished by SEM.

The acrosomal cap projected over a perforatorium surrounded by granular material. At its base, the cap encircled apical projections of the nucleus. The nucleus consisted of dense chromatin, and formed a concave implantation fossa where it joined the midpiece of the tail. For turkey and chicken spermatozoa, the neck region of …

Intrauterine Device (Iud) Associated Pathology: A Review Of Pathogenic Mechanisms, Waldemar A. Schmidt, Karmen L. Schmidt

Scanning Electron Microscopy

This paper summarizes our studies of IUD-related disease with those previously published by others. Our data are based upon 51 IUDs and 42 index cases of IUD-related disease demonstrating specific processes. Gross, dissecting microscope, scanning electron microscope and X-ray microanalysis examinations were made of selected IUDs and associated tissues. Tissue associated with the IUDs revealed inflammation in 59.4%, calcific material in 6.3% and no abnormality in 34.4%. JUD-associated tissue responses were accompanied by changes of the IUD; these changes involved deposition of substances upon the IUD surface and degradation of the JUD itself. Disintegration of the IUD, its string or …