scholarly journals Morphological characterization of hemocytes in Ectemnaspis rorotaense (Floch & Abonnenc) and Ectemnaspis trombetense (Hamada, Py-Daniel & Adler) (Diptera: Simuliidae)

2015 ◽  
Vol 8 (3) ◽  
pp. 209-213
Author(s):  
Juciane Conceição da Silva ◽  
Felipe Arley Costa Pessoa ◽  
Cláudia Maria Ríos-Velásquez ◽  
Helena Rocha Côrrea de Araújo ◽  
Ana Paula Sampaio Feitosa ◽  
...  
Keyword(s):  
Cell Types ◽  
Microscopy Study ◽  
Morphological Characterization ◽  
Electron Microscopy Study ◽  
Black Flies ◽  
Morphological Variations ◽  
Transmission Electron ◽  
Amazonas State ◽  
First Time

Abstract. Hemocytes are insect immune cells which are responsible for processes of phagocytosis, encapsulation, and coagulation. This study aim to characterize the hemocyte cells in two species amazon blackflies: Ectemnaspis rorotaense (Floch & Abonnenc) and Ectemnaspis trombetense (Hamada, Py-Daniel & Adler). Black fly larvae and pupae were collected from streams in Presidente Figueiredo Municipality, Amazonas State, Brazil. Hemolymph of 36 individuals of E. rorotaense (12 larvae, 12 pupae and 12 adults) and 38 of E. trombetense (12 larvae, 12 pupae and 14 adults) were collected and the cells were characterized by light microscopy; 200 adults of each species were used to transmission electron microscopy study. In this work were showed, by the first time, the hemocyte cells of black flies amazon. Four cell types were identified: prohemocytes, granulocytes, oenocytoids, and plasmatocytes. Prohemocytes were the smallest cells and they exhibited a high nuclear-cytoplasmic ratio. Granulocytes possessed large, eccentric nuclei, and they were characterized by the presence of granules that differed in size and shape. Oenocytoids presented poorly developed nucleus with localization in central region. Plasmatocytes showed more morphological variations and large projections in the cytoplasmic membrane. The prohemocytes were the most frequent in E. rorotaense, with nearby 45% of total cells, whereas plasmatocytes and granulocytes, each one with 38%, were the most abundant in E. trombetense. This study showed that prohemocytes, granulocytes, oenocytoids, and plasmatocytes were present in the hemolymph of E. rorotaense and E. trombetense during all stages.Caracterização Morfológica de Hemócitos em Ectemnaspis rorotaense (Floch & Abonnenc) e Ectemnaspis trombetense (Hamada, Py-Daniel & Adler) (Diptera: Simuliidae)Resumo. Os hemócitos são células do sistema imune dos insetos responsáveis pelos processos de fagocitose, encapsulação e coagulação. O objetivo desse trabalho foi caracterizar os hemócitos nos simulídeos amazônicos, Ectemnaspis rorotaense (Floch & Abonnenc)e Ectemnaspis trombetense (Hamada, Py-Daniel & Adler). Larvas e pupas de simulídeos foram coletadas em igarapés no município de Presidente Figueiredo, Amazonas, Brasil. Para caracterização celular através da microscopia óptica, foi coletada a hemolinfa de 36 espécimes (12 larvas, 12 pupas e 12 adultos) de E. rorotaense e 38 espécimes (12 larvas, 12 pupas e 14 adultos) de E. trombetense. Para o estudo com microscopia eletrônica de transmissão, 200 adultos de cada espécie foram utilizados. Neste trabalho foram descritos, pela primeira vez, os hemócitos de simulídeos amazônicos. Foram identificados quatro tipos celulares em larvas, pupas e adultos: prohemócitos, plasmatócitos, granulócitos e oenocitóides. Os prohemócitos, com um núcleo volumoso em relação ao citoplasma, se mostraram as menores células. Os granulócitos foram caracterizados pela presença de grânulos de diferentes tamanhos e formas e um núcleo grande e excêntrico. Os oenocitóides revelaram núcleo pouco desenvolvido, geralmente localizado na região central. Os plasmatócitos apresentaram grandes projeções da membrana citoplasmática e maior variação morfológica. Os prohemócitos foram as células mais frequentes em E. rorotaense com 45% do total das células, enquanto os plasmatócitos e granulócitos, ambas com 38% cada, foram as mais abundantes em E. trombetense. Esse estudo mostrou que prohemócitos, granulócitos, oenocitóides e plasmatócitos são presentes na hemolinfa de E. rorotaense and E. trombetense durante todos os estágios.

scholarly journals Morphological and Ultrastructural Characterization of Hemocytes in an Insect Model, the Hematophagous Dipetalogaster maxima (Hemiptera: Reduviidae)

Insects ◽  
2021 ◽  
Vol 12 (7) ◽  
pp. 640
Author(s):  
Natalia R. Moyetta ◽  
Fabián O. Ramos ◽  
Jimena Leyria ◽  
Lilián E. Canavoso ◽  
Leonardo L. Fruttero
Keyword(s):  
Cell Biology ◽  
Cell Types ◽  
Transmission Electron ◽  
Ultrastructural Characterization ◽  
Current Classification ◽  
Contrast Microscopy ◽  
First Time ◽  
Controversial Aspect

Hemocytes, the cells present in the hemolymph of insects and other invertebrates, perform several physiological functions, including innate immunity. The current classification of hemocyte types is based mostly on morphological features; however, divergences have emerged among specialists in triatomines, the insect vectors of Chagas’ disease (Hemiptera: Reduviidae). Here, we have combined technical approaches in order to characterize the hemocytes from fifth instar nymphs of the triatomine Dipetalogaster maxima. Moreover, in this work we describe, for the first time, the ultrastructural features of D. maxima hemocytes. Using phase contrast microscopy of fresh preparations, five hemocyte populations were identified and further characterized by immunofluorescence, flow cytometry and transmission electron microscopy. The plasmatocytes and the granulocytes were the most abundant cell types, although prohemocytes, adipohemocytes and oenocytes were also found. This work sheds light on a controversial aspect of triatomine cell biology and physiology setting the basis for future in-depth studies directed to address hemocyte classification using non-microscopy-based markers.

scholarly journals A Novel Genotype and First Record of Trypanosoma lainsoni in Argentina

Pathogens ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 731
Author(s):  
Anahí G. Díaz ◽  
Paula G. Ragone ◽  
Fanny Rusman ◽  
Noelia Floridia-Yapur ◽  
Rubén M. Barquez ◽  
...  
Keyword(s):  
Host Range ◽  
First Record ◽  
Morphological Characterization ◽  
Pairwise Identity ◽  
Wild Mammals ◽  
Transmission Electron ◽  
Chaco Region ◽  
Veterinary Importance ◽  
First Time

Trypanosomes are a group of parasitic flagellates with medical and veterinary importance. Despite many species having been described in this genus, little is known about many of them. Here, we report a genetic and morphological characterization of trypanosomatids isolated from wild mammals from the Argentine Chaco region. Parasites were morphologically and ultrastructurally characterized by light microscopy and transmission electron microscopy. Additionally, 18s rRNA and gGAPDH genes were sequenced and analyzed using maximum likelihood and Bayesian inference. Morphological characterization showed clear characteristics associated with the Trypanosoma genus. The genetic characterization demonstrates that the studied isolates have identical sequences and a pairwise identity of 99% with Trypanosoma lainsoni, which belongs to the clade of lizards and snakes/rodents and marsupials. To date, this species had only been found in the Amazon region. Our finding represents the second report of T. lainsoni and the first record for the Chaco region. Furthermore, we ultrastructurally described for the first time the species. Finally, the host range of T. lainsoni was expanded (Leopardus geoffroyi, Carenivora, Felidae; and Calomys sp., Rodentia, Cricetidae), showing a wide host range for this species.

Adaptation for Carnivory in the West Australian pitcher plant Cephalotus follicularis Labill

1984 ◽  
Vol 32 (6) ◽  
pp. 595 ◽  
Author(s):  
DM Parkes ◽  
ND Hallam
Keyword(s):  
Cell Types ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
The West ◽  
Pitcher Plant ◽  
Mesophyll Cells ◽  
Surface Microtopography ◽  
Transmission Electron ◽  
Different Types ◽  
Gland Tissue

The West Australian pitcher plant Cephalotus follicularis has adaptive structures for carnivory including modified leaves as pitfall containers, specialized surface microtopography to reduce adhesion of insect footpads and the development of gland tissue that secretes digestive enzymes. Gland masses on the lateral pitcher walls are made up of unspecialized mesophyll cells supporting two different types of gland. Cephalotus is geographically and taxonomically isolated from other pitcher plants. A detailed scanning electron and transmission electron microscopy study of the cell types within the pitchers of Cephalotus was carried out and the evolutionary and taxonomic significance of its adaptions to carnivory are discussed.

High-Resolution Transmission Electron Microscopy Study of Nanostructured Hydroxyapatite

2008 ◽  
Vol 14 (5) ◽  
pp. 433-438 ◽  
Author(s):  
Daniel Biggemann ◽  
Marcelo H. Prado da Silva ◽  
Alexandre M. Rossi ◽  
Antonio J. Ramirez
Keyword(s):  
Electron Microscopy ◽  
Transmission Electron Microscopy ◽  
High Resolution ◽  
Spherical Aberration ◽  
Microscopy Study ◽  
Lattice Parameter ◽  
Electron Microscopy Study ◽  
Restoration Technique ◽  
Transmission Electron ◽  
First Time

AbstractCrystalline properties of synthetic nanostructured hydroxyapatite (n-HA) were studied using high-resolution transmission electron microscopy. The focal-series-restoration technique, obtaining exit-plane wavefunction and spherical aberration-corrected images, was successfully applied for the first time in this electron-beam-susceptible material. Multislice simulations and energy dispersive X-ray spectroscopy were also employed to determine unequivocally that n-HA particles of different size preserve stoichiometric HA-like crystal structure. n-HA particles with sizes of twice the HA lattice parameter were found. These results can be used to optimize n-HA sinterization parameters to improve bioactivity.

In-situ Scanning Transmission Electron Microscopy Study on the Microstructural Characterization of a TFT-LCD Panel by a FIB/SEM

2008 ◽  
Vol 14 (S2) ◽  
pp. 1020-1021
Author(s):  
YJ Park ◽  
SH Han ◽  
HN Kim
Keyword(s):  
New Mexico ◽  
Scanning Transmission Electron Microscopy ◽  
Microstructural Characterization ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Transmission Electron Microscopy Study ◽  
Transmission Electron ◽  
Scanning Transmission

Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008

TEM Characterization of Two Spark Plasma Sintered Fe-1.5wt.%Mo Steels Stabilized with SiO2 and TiO2

2008 ◽  
Vol 604-605 ◽  
pp. 187-201
Author(s):  
Marcello Cabibbo
Keyword(s):  
Volume Fraction ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Fine Grained ◽  
Plasma Sintering ◽  
Transmission Electron ◽  
Fine Grained Structure ◽  
Spark Plasma ◽  
Boundary Stability

This paper presents a transmission electron microscopy study of two Fe-1.5wt.%Mo steels stabilized with 1.5wt.%SiO2 and 1.5wt.%TiO2,respectively, and compacted through spark plasma sintering. The microstructure inspections revealed that sintered FeMo+SiO2 is able to maintain a nanometric scale grained structure up to a sintering temperature of 815°C, while the steel modified with TiO2 retained its nanometric scale microstructure up to 900°C. The ultra-fine grained structure (within 100-150 nm) was also directly correlated to the grain boundary stability through systematic extinction contours survey. Local nano-welding phenomena shows the effective compacting process of the Fe-Mo powders during sintering. Residual nano-porosity was found to decorate most of the grain boundaries and the triple grain junctions in all the sintering conditions examined, although this nano-porosity accounted for values within 0.26% in volume fraction.

The role of boundaries in the superconducting properties of sintered YBa2Cu3O7−x

1987 ◽  
Vol 2 (6) ◽  
pp. 750-756 ◽  
Author(s):  
R. A. Camps ◽  
J. E. Evetts ◽  
B. A. Glowacki ◽  
S. B. Newcomb ◽  
W. M. Stobbs
Keyword(s):  
Technological Development ◽  
Microscopy Study ◽  
Electron Microscopy Study ◽  
Superconducting Properties ◽  
Transmission Electron Microscopy Study ◽  
The Poor ◽  
Transmission Electron ◽  
Superconducting Oxides

Since the discovery of high critical temperature superconducting oxides, an important factor potentially limiting their technological application has been the typically low value of the critical current density that they can carry. Here are presented the results of a transmission electron microscopy study of sintered YBa2Cu3O7−x aimed primarily at the characterization of those elements of the microstructure responsible for the poor current-carrying capacity in the superconducting state. The observations are further discussed in relation both to the flux pinning characteristics required and to the prospect for controlling the microstructure in order to optimize the properties of this material for technological development.

Sign in / Sign up

Export Citation Format

Share Document