scholarly journals ANALYSIS OF STRUCTURAL PLASTICITY IN THE HONEY BEE BRAIN USING THE CAVALIERI ESTIMATOR OF VOLUME AND THE DISECTOR METHOD

2011 ◽  
Vol 19 (2) ◽  
pp. 139 ◽  
Author(s):  
Sheena M Brown ◽  
Ruth MA Napper ◽  
Alison R Mercerl
Keyword(s):  
Electron Microscopy ◽  
Honey Bee ◽  
Antennal Lobe ◽  
Light And Electron Microscopy ◽  
Age Groups ◽  
Structural Plasticity ◽  
Light Microscope Level ◽  
Heterogeneous Distribution ◽  
Data Points ◽  
The Central Nervous System

The antennal lobe of the worker honey bee has been used as a model system to address the origins of structural plasticity in the central nervous system. A combination of light and electron microscopy was used to determine total synapse number within an easily identifiable sub-unit of the antennal lobe neuropil, the T4-2(1) glomerulus. The Cavalieri method was applied at the light microscope level to determine a reference volume (Vref) of this glomerulus. Using transmission electron microscopy, the physical disector was used to determine synaptic density (Nv) within the T4-2(1) glomerulus. An estimate of the total synapse number N(syn) was determined by; N(syn) = V(ref) Nv. Newly emerged, 4-day old,10-day old and forager-aged bees were analysed. Results showed that despite a significant increase in T4-2(1) volume with age, the total number of synapses in this glomerulus did not show a corresponding increase. Disturbingly, it is possible that huge variances within age groups, due to one or two outlying data points, could be masking the true trend of synapse number. This variance, the heterogeneous distribution of synapses within this glomerulus and the problems associated with reproducibility of synapse counts are discussed.

Cytology and ultrastructure of Thanatephorus cucumeris and related taxa of the Rhizoctonia complex

1977 ◽  
Vol 55 (18) ◽  
pp. 2419-2436 ◽  
Author(s):  
C. C. Tu ◽  
James W. Kimbrough ◽  
H. C. Aldrich
Keyword(s):  
Electron Microscopy ◽  
Light Microscope ◽  
Light And Electron Microscopy ◽  
Middle Layer ◽  
Ultrastructural Level ◽  
Aniline Blue ◽  
Diploid Nucleus ◽  
Thanatephorus Cucumeris ◽  
Light Microscope Level ◽  
Endoplasmic Reticula

Cytological studies on the vegetative hyphae of members of the Rhizoctonia complex and basidial structures of Thanatephorus cucumeris were performed with light and electron microscopy. Vegetative cells of Thanatephorus and Waitea proved to be multinucleate, whereas those of Uthatobasidium, Ceratobasidium, Athelia. and Botryobasidium are binucleate.Dolipore septa of Thanatephorus, Waitea, Uthatobasidium, and Ceratobasidium are visible with the light microscope when stained with aniline blue in glycerine. Ultrastructurally, pore caps in these genera consisted of two-layered unit membranes, forming cisternae with an electron-dense middle layer. Dolipore septa of Athelia (S. rolfsii) and Botryobasidium are not visible in aniline blue at the light microscope level. At the ultrastructural level, there was an additional cisternal membrane making up a pore cap of three membranes. The fine structure of nuclei, mitochondria, endoplasmic reticula, vacuoles, and other organelles in the basidial structures of T. cucumeris was essentially the same as in other basidiomycetes.Karyogamy of two haploid nuclei occurs in the young basidia of T. cucumeris. The nuclear envelopes of both haploid nuclei break at their adjacent sides and fuse to form a diploid nucleus. After a short interphase, meiosis occurs. No leptotene was observed at prophase I, but a synaptinemal complex was evident and six pairs of chromosomes were observed throughout pachytene, diplotene, and diakinesis. The nuclear envelope disappears at metaphase I and a spindle appears. The second meiotic division is equational. Most of the mature and discharged spores are uninucleate.

scholarly journals Spermatid Giant Cells, Tubular Hypospermatogenesis, Spermatogonial Swelling, Cytoplasmic Vacuoles, and Tubular Dilatation in the Testes of Normal Rabbits

1986 ◽  
Vol 23 (2) ◽  
pp. 176-183 ◽  
Author(s):  
D. Morton ◽  
S. E. Weisbrode ◽  
W. E. Wyder ◽  
J. K. Maurer ◽  
C. C. Capen
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Age Groups ◽  
Giant Cells ◽  
Seminiferous Tubules ◽  
Intercellular Bridges ◽  
Nuclear Membranes ◽  
Cytoplasmic Vacuoles ◽  
New Zealand White Rabbits ◽  
Tubular Dilatation

Testes of 36 normal New Zealand white rabbits (8, 15, 18, 26, and greater than 52 weeks of age) were examined by light and electron microscopy. The incidence and number of affected tubules were determined for spermatid giant cells, focal tubular hypospermatogenesis, cytoplasmic swelling of spermatogonia, intracytoplasmic vacuoles in seminiferous epithelium, and tubular dilatation. Spermatogenesis commenced at 15–18 weeks of age and was present in all rabbits by 18 weeks. Spermatid giant cells occurred in 96% of rabbits 15 weeks of age and older. Focal hypospermatogenesis was present in 14–57% of testes once active spermatogenesis began. Ninety-seven percent of testes in all age groups combined had spermatogonial swelling. Infrequent dilated seminiferous tubules were present in five rabbits. Ultrastructurally, spermatid giant cells were round cells with multiple nuclei that appeared to arise by widening of narrow intercellular bridges that normally connect spermatogenic epithelial cells. Pale-staining spermatogonia consisted of cytoplasmic and nuclear swelling with disruption of plasma and nuclear membranes. Tubules with spermatogonial swelling were more numerous in 15- and 18-week-old rabbits. There were no significant differences in incidence or extent of spermatid giant cells, focal hypospermatogenesis, cytoplasmic vacuoles, or tubular dilatation between age groups after spermatogenesis commenced. Although the cause of these changes is not known, they were frequent findings in normal rabbits 15 weeks of age and older.

scholarly journals Sensory and neurosecretory innervation of leech nephridia is accomplished by a single neurone containing FMRFamide

1993 ◽  
Vol 182 (1) ◽  
pp. 81-96 ◽  
Author(s):  
A. Wenning ◽  
M. A. Cahill ◽  
U. Hoeger ◽  
R. L. Calabrese
Keyword(s):  
Electron Microscopy ◽  
Mass Spectrometry ◽  
Central Nervous System ◽  
High Pressure ◽  
Neural Control ◽  
Light And Electron Microscopy ◽  
Medicinal Leech ◽  
Edman Degradation ◽  
Reverse Phase ◽  
The Central Nervous System

The neural control of the excretory system of the medicinal leech Hirudo medicinalis has been characterized morphologically and chemically using light and electron microscopy, immunocytochemistry and biochemistry. Immunoreactivity against RFamide-like peptides revealed elaborate neuronal aborizations of a neurone in the nephridium, around the urinary bladder sphincter and in the central nervous system. The processes arose from the nephridial nerve cell (NNC), a previously identified receptor neurone. Using a combination of reverse-phase high pressure liquid chromatography, radioimmunoassay and subsequent Edman degradation and mass spectrometry, authentic FMRFamide has been identified as the major peptide of the NNC. Sensory and neurosecretory innervation of the nephridia is thus accomplished by a single neurone, which is thought to modulate nephridial performance.

THE MANUFACTURE AND BURIAL OF HOHOKAM DISK BEADS IN THE TUCSON BASIN

2018 ◽  
Vol 83 (3) ◽  
pp. 536-551 ◽  
Author(s):  
Jenny L. Adams ◽  
Mary F. Ownby
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Honey Bee ◽  
Energy Dispersive Spectrometry ◽  
Age Groups ◽  
Energy Dispersive ◽  
Tucson Basin ◽  
Macroscopic Examination ◽  
Scanning Electron

Recent examinations of more than 13,000 disk beads from mortuary contexts determined that macroscopic examination was not always enough to distinguish shell, stone, and fired-clay beads. Using replication experiments and scanning electron microscopy energy dispersive spectrometry (SEM-EDS), we update the 80-year-old conclusions of Emil Haury, who defined features distinctive to bead manufacture. With this renewed confidence in materials identification, we analyzed the distributions of disk beads made from shell, stone, and fired clay among Hohokam inhumations and cremations at the Yuma Wash, Honey Bee Village, and Wetlands sites in the Tucson Basin. Not everyone was buried with disk beads, but all age groups were represented among those who were buried with beads. Some people were buried with only stone, or only shell, or only fired-clay beads, although more were buried with beads of some combination of these three materials. In this article, we consider why fired-clay beads were added to the mix and conclude that they were made as acceptable substitutes for stone beads, not for deceptive reasons concerning wealth or status, but rather in imitation of stone to honor a tradition that could not otherwise be efficiently met.

Localization of Actin Filaments in the Central Nervous System Using Phalloidin and Correlative Light and Electron Microscopy

1999 ◽  
Vol 5 (S2) ◽  
pp. 498-499
Author(s):  
Francisco Capani ◽  
Maryann E. Martone ◽  
Thomas J. Deerinck ◽  
Mark H. Ellisman
Keyword(s):  
Electron Microscopy ◽  
Central Nervous System ◽  
Nervous System ◽  
Actin Filaments ◽  
Cold Water ◽  
Light And Electron Microscopy ◽  
Actin Binding ◽  
Electron Microscopic Level ◽  
The Central Nervous System ◽  
Structural Methods

Determination of the fine organization of actin networks is important for understanding different functional aspects of the central nervous system (CNS) such as plastic events. Early studies investigating the localization of actin filaments at the ultrastructural level relied on structural methods or antibodies raised against actin isoforms. More recently, many investigators have employed the actin-binding peptide phalloidin conjugated to various fluorescent molecules. By conjugating phalloidin to the fluorophore eosin, we have been able to localize f-actin at the electron microscopic level using photooxidation of diaminobenzidine (DAB) by eosin. The goal of this study is to provide a better description of the cellular and subcellular localization of actin filaments at the light and electron microscopy level based on the high binding affinity of phalloidin for actin and utilizing this novel method.Tissues were obtained from male Sprague Dawley rats that were perfused transcardially under deep anesthesia with normal rat Ringer's solution at 35°C followed by fixative. The fixative contained 4 % paraformaldehyde and different concentrations of glutaraldehyde, ranging from 0.1- 2.5%. Sections of cerebellum, striatum and hippocampus which were cut at a thickness of 50-80 μm with a Vibratome were incubated with phalloidin-eosin in a solution of 0.05% in 0.5% cold water fish gelatin/50mM glycine-PBS (“working buffer”) for 2 hrs. As a control, phalloidin-eosin was omitted for one set of tissues.

Light and electron microscopy of conjugation in the yeast, Schizosaccharomyces octosporus

1982 ◽  
Vol 28 (9) ◽  
pp. 1059-1077 ◽  
Author(s):  
M.-L. Ashton ◽  
P. B. Moens
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Spindle Pole Body ◽  
Spindle Pole ◽  
Microscope Level ◽  
Nuclear Movement ◽  
Light Microscope Level ◽  
Spindle Pole Bodies ◽  
Interference Contrast Microscopy ◽  
Fluorescent Spot

Conjugation in Schizosaccharomyces octosporus is described through the use of interference contrast microscopy, fluorescence microscopy, and electron microscopy of serial sections. At the light microscope level, mating was frequently observed to occur between cells of common ancestry. Fluorescent staining of the nuclei showed that nuclear migration occurs prior to karyogamy, and following diploidization the nucleus then migrates to the end of the cell. A brightly fluorescent spot was found at the apex of the migration nucleus. At the electron microscope level, the results showed that nuclear movement occurs in the presence of cytoplasmic microtubules that are associated with the spindle pole body, the conjugatory nuclei first fuse at or near the spindle pole bodies, and fusion of the spindle bodies occurs apparently by stacking one onto the other.

The Morphology of Vacuolated Cells in the Liver Following Administration of Vitamin A.

1973 ◽  
Vol 31 ◽  
pp. 408-409
Author(s):  
Odell T. Minick ◽  
Hidejiro Yokoo ◽  
Fawzia Batti
Keyword(s):  
Electron Microscopy ◽  
Body Weight ◽  
Vitamin A ◽  
Light And Electron Microscopy ◽  
Liver Cells ◽  
Prominent Feature ◽  
Vascular Space ◽  
Vacuolated Cell ◽  
Vacuolated Cells ◽  
Vacuolated Cytoplasm

Vacuolated cells in the liver of young rats were studied by light and electron microscopy following the administration of vitamin A (200 units per gram of body weight). Their characteristics were compared with similar cells found in untreated animals.In rats given vitamin A, cells with vacuolated cytoplasm were a prominent feature. These cells were found mostly in a perisinusoidal location, although some appeared to be in between liver cells (Fig. 1). Electron microscopy confirmed their location in Disse's space adjacent to the sinusoid and in recesses between liver cells. Some appeared to be bordering the lumen of the sinusoid, but careful observation usually revealed a tenuous endothelial process separating the vacuolated cell from the vascular space. In appropriate sections, fenestrations in the thin endothelial processes were noted (Fig. 2, arrow).

Control of Autogenous Vein Grafts Prior to Reimplantation, By Electron Microscopy

1972 ◽  
Vol 30 ◽  
pp. 106-107
Author(s):  
John H. L. Watson ◽  
John L. Swedo ◽  
M. Vrandecic
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Physiological Saline ◽  
Experimental Conditions ◽  
Vein Grafts ◽  
Arterial Blood ◽  
Saphenous Veins ◽  
Autogenous Vein ◽  
Control Of Parameters ◽  
Post Implantation

The ambient temperature and the nature of the storage fluids may well have significant effects upon the post-implantation behavior of venus autografts. A first step in the investigation of such effects is reported here. Experimental conditions have been set which approximate actual operating room procedures. Saphenous veins from dogs have been used as models in the experiments. After removal from the dogs the veins were kept for two hours under four different experimental conditions, viz at either 4°C or 23°C in either physiological saline or whole canine arterial blood. At the end of the two hours they were prepared for light and electron microscopy. Since no obvious changes or damage could be seen in the veins by light microscopy, even with the advantage of tissue specific stains, it was essential that the control of parameters for successful grafts be set by electron microscopy.

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