The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
The secretion apparatus known as the needle complex (NC) from the bacterium Shigella flexneri was studied by single particle electron microscopy. The isolated intact NC appears in projection to be composed of a basal body consisting of seven rings and a protruding needle appendage. A comparison of averaged projections of the intact NC and its fragments revealed the organization of the NC into several...
In order to improve cytogenetical analyses on fish, especially focusing on delicate and rare species, we have adopted a new in vitro methodology using dead animals. The results obtained from 24 neotropical freshwater and marine fish species demonstrate that chromosomes can be obtained under post-mortem conditions. Significantly, the samples analyzed provided reliable cytogenetical data in nearly all...
Hydrotaea chalcogaster is a fly species of medical and forensic importance in many parts of the world. In this study, we investigated the sensilla of the antenna and palp of the adult female fly using scanning electron microscopy. The antennal scape has one type of sensillum, the sharp-tipped sensillum trichodeum; whereas, the antennal pedicel also possessed this type of sensillum in addition to an...
Synaptic bodies (SBs) are small, prominent organelles in pinealocytes, most probably involved in signal transduction processes. To check the influence of the photoperiod on their shape plasticity and number we chose two extreme lighting conditions, i.e. 20h of illumination followed by 4h of darkness (LD 20:4) versus (LD 4:20). Pineal glands were assessed at 0, 4 and 13h after dark onset. Under both...
The definitive fate of peripherally injected PKH26 labelled bone marrow mononuclear cells expressing the CD34+ antigen following experimental myocardial cryodamage in rats (n=10) has been examined by direct visualization on photoconverted light and electron microscopy images.One week after the injection in each rat of about 150,000 CD34+ cells early stage PKH26+ vascular structures were localized...
The present study describes the short-term alterations in the prostate ventral and dorsal lobe of the adult Mongolian gerbil, in response to two different androgen suppression approaches. Groups (n=6) of 16-week-old gerbils were maintained intact or subjected, either to the bilateral surgical castration 1 week previously or to daily subcutaneous injections of Flutamide (10mg/kg body weight) for 7...
We used a hydrophobic micro-textured poly-dimethylsiloxane (PDMS) in the presence of serum protein at 37°C to study the motility of mouse stromal fibroblast on variant (15–100μm) parallel ridge/groove with 30μm depth. In this paper, we observed the temporal changes in cell morphology and locomotion by using time-lapse phase-contrast microscopy. When fibroblasts seeded onto the micro-grooved substrate,...
Energy filtering TEM (EFTEM) with modern spectrometers and software offers new possibilities for element analysis and image generation in plant cells. In the present review, applications of EFTEM in plant physiology, such as identification of light elements and ion transport, analyses of natural cell incrustations, determination of element exchange between fungi and rootlets during mycorrhiza development,...
We performed microspectroscopic evaluation of the pigment composition of the photosynthetic compartments of both algae and higher plants. The feasibility of microspectroscopy for discriminating among species and/or phylogenetic groups was tested on laboratory cultures. Gaussian bands decompositions, and a fitting algorithm, together with fourth-derivative transformation of absorbance spectra, provided...
Eurysternus caribaeus was analyzed cytologically by conventional chromosomal staining. The species presents a diploid number of 2n=8, chromosomes with two arms and an XY sex determining mechanism. This is the first karyotype described for the genus Eurysternus and the tribe Eurysternini, and is also the smallest diploid number observed in the family Scarabaeidae and superfamily Scarabaeoidea.
This study is aimed at demonstrating the role played by a calpastatin isoform (Xcalp3) in Xenopus embryos. A specific monoclonal antibody (mAb) was raised against a glutathione S-transferase (GST)-Xcalp3 fusion protein and characterized by immunoblotting and confocal fluorescence microscopy on stage 20–36 embryos. Under these conditions, calpastatin reactivity is associated with a major 110kDa protein...
Lysosomes of trypanosomatid protozoa are poorly known. In this work we have cytochemically detected the lysosomal enzyme aryl sulphatase in the trypanosomatids Trypanosoma cruzi and Crithidia fasciculata, by using p-nitrocatecholsulphate as substrate. Positive reaction was located exclusively inside membrane-bound cytoplasmic vesicles distributed throughout the cell body. Electron-dense reaction was...
The caveolar cycle is thought to be regulated by synchronised function of kinases and phosphatases. Using ocadaic acid – a serine/threonine protein phosphatase inhibitor – and an inhibitor of tyrosine phosphatase (sodium orthovanadate) we have followed the internalisation of caveolae. Since albumin binding to its receptor (gp60) can induce pinching off of caveolae from the plasma membrane, we also...
In this article several experimentally identified Mn valence-sensitive ELNES quantities for the La 1−x Sr x MnO 3 compound class are presented, namely the energy separations between Mn-L 3 and O-K a , between O-K b and O-K a edges, the Mn-L 2,3 white line intensity ratio, and the Mn-L 3 line width. Valence sensitivities of these...
Polycarbonate films (thickness 18, 25 and 38μm) were irradiated by a beam of 100MeV Ni 7+ ion. The permeability for hydrogen and carbon dioxide was measured from both sides of membrane at increasing etching time. These membranes show larger permeability from the irradiation side, than the reverse side indicating the formation of conical tracks and asymmetrical membrane. The stopping range...
Transmission electron microscopy (TEM) observations have been extensively applied to follow the route of luteovirids in their vectors. Luteovirids are icosahedral plant viruses which are phloem-limited and strictly transmitted in a circulative manner by aphids. Virus particles, acquired by aphids while feeding on an infected plant, circulate in the aphid's body without replication and are internalized...
We generated the muscle aquaporin 4 (AQP4) overexpressing transgenic mice in order to investigate the skeletal muscle pathology at RNA and protein levels. At RNA level, the AQP4 mRNA expression of soleus, EDL and cardiac muscles in Tg mice was statistically significantly higher than that in wild mice by the real-time reverse transcription polymerase chain reaction method. At protein level examinations,...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.