scholarly journals SURFACE STRUCTURE OF ISOLATED NEURONS

1970 ◽  
Vol 47 (2) ◽  
pp. 319-331 ◽  
Author(s):  
Anders Hamberger ◽  
Hans-Arne Hansson ◽  
Johan Sjöstrand
Keyword(s):  
Electron Microscopy ◽  
Hypoglossal Nerve ◽  
Light And Electron Microscopy ◽  
Neuronal Cell ◽  
Spherical Particles ◽  
Hypoglossal Nucleus ◽  
Isolated Neurons ◽  
Tissue Sections ◽  
Neuronal Cell Bodies ◽  
Transmission Electron

Freehand, isolated neuronal perikarya from the hypoglossal nucleus of the rabbit have been examined with light-and electron-microscopy (transmission and scanning). The surface of the cell bodies was largely covered with spherical particles which were 0.5–2 µ in diameter. Transmission electron microscopy proved that the spherical particles were synaptic nerve terminals. Crush of the hypoglossal nerve which leads to chromatolysis and swelling of the neuronal cell bodies results in a conspicuous reduction in the number of terminals attached to the surface of hypoglossal neurons. This effect was observed both for isolated neurons and in tissue sections. The effect is considered in relation to earlier reported variations in the adherence of neuropil to isolated neuronal perikarya. The functional importance of nerve ending detachment in connection with nerve injury is discussed.

Investigation of Tickborne Pathogens within Naturally Infected Brown Dog Tick (Ixodidae: Rhipicephalus Sanguineus) in Egypt by Light and Electron Microscopy

2020 ◽  
Keyword(s):  
Electron Microscopy ◽  
Salivary Gland ◽  
Light And Electron Microscopy ◽  
Rhipicephalus Sanguineus ◽  
Mammalian Host ◽  
Babesia Canis ◽  
Brown Dog Tick ◽  
Transmission Electron ◽  
Dog Tick ◽  
Theileria Spp

Tick borne pathogens present a significant health challenge to animals and human because a single tick may transmit multiple pathogens to a mammalian host during feeding. The present study detected tick-borne pathogens from pet dogs. A total of 666 ticks were collected from 144 pet and sheltered dogs in Egypt from April to September 2018. For hemolymph, midgut and salivary gland smears 546 ticks were used as well as 360 egg smears from 120 female tick were examined by light microscope. The infected ticks were prepared for transmission electron microscopy (TEM). Ticks were identified; Rhipicephalus sanguineus. Light microscopy showed infection rates of 44.69%, 68.50% & 15.75%, in hemolymph, midgut and salivary gland, respectively. H. canis recorded the highest rates in hemolymph and midgut (35.89% & 49.82%, respectively), but Theileria spp. was the lowest (0.73% & 2.93%, respectively). In salivary gland smears, Babesia canis. was detected in 13.55% and Theileria spp. in 1.83%. Mixed infection in same tick was recorded in 4.76% &0.37% in midgut and salivary gland smears, respectively. Babesia canis stages were recovered from 15% of egg smears. R. sanguineus was natural infected by Babesia, Theileria, Hepatozoon and Anaplasma phagocytophilum as well as mixed infections of protozoa accompanied by a complicated sign of diseases and failure in accurate diagnosis.

scholarly journals Localization of ‘Candidatus Liberibacter solanacearum’ and Evidence for Surface Appendages in the Potato Psyllid Vector

2016 ◽  
Vol 106 (2) ◽  
pp. 142-154 ◽  
Author(s):  
J. M. Cicero ◽  
T. W. Fisher ◽  
J. K. Brown
Keyword(s):  
Electron Microscopy ◽  
Light And Electron Microscopy ◽  
Fluorescence Labeling ◽  
Potato Psyllid ◽  
Bactericera Cockerelli ◽  
Visual Identification ◽  
Transmission Electron ◽  
Candidatus Liberibacter ◽  
Identification Of Bacteria

The potato psyllid Bactericera cockerelli is implicated as the vector of the causal agent of zebra chip of potato and vein-greening of tomato diseases. Until now, visual identification of bacteria in the genus ‘Candidatus Liberibacter’ has relied on direct imaging by light and electron microscopy without labeling, or with whole-organ fluorescence labeling only. In this study, aldehyde fixative followed by a coagulant fixative, was used to process adult psyllids for transmission electron microscopy (TEM) colloidal gold in situ hybridization experiments. Results indicated that ‘Ca. Liberibacter solanacearum’ (CLso)-specific DNA probes annealed to a bacterium that formed extensive, monocultural biofilms on gut, salivary gland, and oral region tissues, confirming that it is one morphotype of potentially others, that is rod-shaped, approximately 2.5 µm in diameter and of variable length, and has a rough, granular cytosol. In addition, CLso, prepared from shredded midguts, and negatively stained for TEM, possessed pili- and flagella-like surface appendages. Genes implicating coding capacity for both types of surface structures are encoded in the CLso genome sequence. Neither type was seen for CLso associated with biofilms within or on digestive organs, suggesting that their production is stimulated only in certain environments, putatively, in the gut during adhesion leading to multiplication, and in hemolymph to afford systemic invasion.

Early innervation of the metanephric kidney

Development ◽  
1988 ◽  
Vol 104 (4) ◽  
pp. 589-599 ◽  
Author(s):  
H. Sariola ◽  
K. Holm ◽  
S. Henke-Fahle
Keyword(s):  
Primary Cultures ◽  
Neuronal Cell ◽  
Similar Distribution ◽  
Renal Tubules ◽  
Experimental Conditions ◽  
Tissue Sections ◽  
Neuronal Cell Bodies ◽  
Metanephric Kidney ◽  
Kidney Morphogenesis

During kidney differentiation, the nephrogenic mesenchyme converts into renal tubules and the ureter bud branches to form the collecting system. Here we show that in the early undifferentiated kidney rudiment there is a third cell type present. In whole-mount preparations of cultured undifferentiated metanephric kidneys, neurones can be detected by immunohistochemical means with antibodies against the neurofilament triplet, 13AA8, and against neuronal cell surface gangliosides, Q211. Clusters of neuronal cell bodies can be seen in the mesenchyme close to the ureter bud. The terminal endings of neurites are found around the mesenchymal condensates that later become kidney tubules. A similar distribution of neurites can be revealed in tissue sections of kidney grafts growing in the chicken chorioallantoic membranes. In primary cultures of the ureter bud cells, neurones are constantly present. In another report, we have shown that, in experimental conditions, neurones are involved in regulation of kidney morphogenesis. The present results raise the possibility that neurones of the metanephric kidney may have this function in vivo as well.

scholarly journals Ultrastructural analysis of the spermatogenesis in the guinea pig (Cavia porcellus)

2016 ◽  
Vol 36 (suppl 1) ◽  
pp. 89-94 ◽  
Author(s):  
Luciana S. Simões ◽  
Rose E.G. Rici ◽  
Phelipe O. Favaron ◽  
Taís Harumi de Castro Sasahara ◽  
Rodrigo S.N. Barreto ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Guinea Pig ◽  
Sexual Development ◽  
Morphological Changes ◽  
Light And Electron Microscopy ◽  
Management Systems ◽  
Cavia Porcellus ◽  
Reproductive Parameters ◽  
Development Stages ◽  
Transmission Electron

Abstract: al for both, the establishment of appropriate management systems, and for the use of new species as animal models. In this study, we used light and electron microscopy to characterize the sexual development stages of the guinea pig (Cavia porcellus) in specimens of 30, 45 and 90 days of age. We observed the differentiation of spermatocytes only through transmission electron microscopy in the leptotene, zygotene and pachytene phases of meiosis, in 30-day-old animals. During puberty, there was differentiation of the germinative epithelium and formation of the acrosome. Spermatozoa, however, were not detected. Thus, we could infer that puberty happens after 45 days of age. Sexual maturity was evident in 90-day-old specimens. Our results showed that changes in the testicular germinative epithelium during the postnatal sexual development in guinea pig led to morphological changes, including the ones related to the development of Leydig and Sertoli cells, which are directly related to puberty. In this work, we provide new morphological subsidies for a better understanding of reproductive parameters of this species, enabling its use as an animal model in the field of the reproductive biology.

scholarly journals The osmium tetroxide-p-phenylenediamine procedure reveals the chromatid cores and kinetochores of meiotic chromosomes by light and electron microscopy.

1996 ◽  
Vol 44 (11) ◽  
pp. 1279-1288 ◽  
Author(s):  
C Antonio ◽  
J M González-García ◽  
J Page ◽  
J A Suja ◽  
J C Stockert ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Reaction Mechanism ◽  
Osmium Tetroxide ◽  
Light And Electron Microscopy ◽  
X Ray ◽  
Meiotic Chromosomes ◽  
Transmission Electron ◽  
Ethanol Acetic Acid ◽  
Electron Imaging ◽  
Z Contrast

We analyzed first-metaphase meiotic chromosomes of the grasshopper Chorthippus jucundus by two different methods, i.e., a silver impregnation technique and the osmium tetroxide-p-phenylenediamine (Os-PPD) procedure. The former was applied on squashed testes previously fixed in ethanol-acetic acid, whereas for Os-PPD the material was not subjected to any previous extraction treatment but was fixed in OsO4, treated with PPD, and embedded in Epon 812. Both techniques revealed chromatid cores and kinetochores regardless of the processing of the material (squashed or sectioned). Unstained Os-PPD sections were analyzed by light microscopy and transmission electron microscopy (TEM). The Os-PPD technique provided a high contrast of chromatid cores and kinetochores in relation to the chromatin, which revealed a low electron density. To determine the Os-PPD reaction mechanism, the PAS procedure, as well as scanning electron microscopy (SEM) backscattering and SEM X-ray microanalysis, was performed on sections. By use of the Os-PPD-PAS procedure, glycol groups formed by oxidation of osmium bound to aromatic substrates were detected in chromatid cores and kinetochores by brightfield and fluorescence microscopy. A high Z contrast was detected in these structures by backscattered electron imaging. SEM X-ray microanalysis showed osmium and phosphorus to be the main elements present on the chromatid cores. Taking into account the known reactivity of OsO4 and the present results, the possible participation of nucleic acids as well as proteins in the Os-PPD reaction mechanism and in the composition of chromatid cores and kinetochores is discussed.

Nanostructured CaWO4, CaWO4 : Pb2+ and CaWO4 : Tb3+ Particles: Polyol-Mediated Synthesis and Luminescent Properties

2007 ◽  
Vol 7 (2) ◽  
pp. 602-609 ◽  
Author(s):  
Zhenling Wang ◽  
Guangzhi Li ◽  
Zewei Quan ◽  
Deyan Kong ◽  
Xiaoming Liu ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Uv Light ◽  
Blue Emission ◽  
Luminescent Properties ◽  
Spherical Particles ◽  
Sem Images ◽  
Blue Emission Band ◽  
Transmission Electron ◽  
Characteristic Emission ◽  
20 Nm

Nano-submicrostructured CaWO4, CaWO4 : Pb2+ and CaWO4 : Pb3+ particles were prepared by polyol method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), Fourier transform infrared spectra (FT-IR), thermogravimetry-differential thermal analysis (TG-DTA), photoluminescence (PL), cathodoluminescence (CL) spectra and PL lifetimes. The results of XRD indicate that the as-prepared samples are well crystallized with the scheelite structure of CaWO4. The FE-SEM images illustrate that CaWO4 and CaWO4 : Pb2+ and CaWO4 : Tb3+ powders are composed of spherical particles with sizes around 260, 290, and 190 nm respectively, which are the aggregates of smaller nanoparticles around 10–20 nm. Under the UV light or electron beam excitation, the CaWO4 powders exhibits a blue emission band with a maximum at about 440 nm. When the CaWO4 particles are doped with Pb2+, the intensity of luminescence is enhanced to some extent and the luminescence band maximum is red shifted to 460 nm. Tb3+-doped CaWO4 particles show the characteristic emission of Tb3+ 5D4–7FJ (J = 6 – 3) transitions due to an energy transfer from WO42− groups to Pb3+.

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