Description of pleural defensive organs in three species of firefly larvae (Coleoptera, Lampyridae)

Zootaxa ◽  
2004 ◽  
Vol 768 (1) ◽  
pp. 1 ◽  
Author(s):  
ERNEST TRICE ◽  
JOHN TYLER ◽  
JOHN C. DAY

Although reflex bleeding as a defence mechanism is well characterised in the adult lampyrid little is known of the defensive mechanisms of immature bioluminescent beetles. A detailed comparative examination of the morphology and microstructure of the pleural defensive organs of Lampyris noctiluca L., Luciola cruciata Motschulsky and a Nyctophila species obtained from Amol forest, Iran, using light microscopy and epifluorescent imaging, revealed vesicles continuous with the pleural organ membrane and held in place by a disc structure. Structural differences were apparent between species. We speculate on the function and evolution of these organs among the Lampyridae.

1995 ◽  
Vol 32 (6) ◽  
pp. 455-462 ◽  
Author(s):  
Carroll-Ann Trotman ◽  
David Hou ◽  
Alphonse R. Burdi ◽  
Steven R. Cohen ◽  
David S. Carlson

The two specific aims of this study were as follows: to evaluate the appropriateness of the A/Jax mouse model in the investigation of the key cellular stages in prenatal soft palate morphogenesis and myogenesis; and to describe structural differences in the histomorphology of the soft palate anatomy from cleft and noncleft mice prior to, during, and after palatogenesis. Cleft-induced and control groups of A/Jax mouse embryos from timed pregnancies were harvested sequentially on gestational days 15 to 19. Embryos were weighed and staged for external body morphology. The heads were removed and fixed for light microscopy, sectioned serially in the frontal plane at 10 μm and stained with hematoxylin-eosin to characterize and compare the soft palate musculature. All observations were made at the head depth of the trigeminal ganglion in both age- and stage-matched embryos. The following findings were made: (1) the A/Jax mouse is a suitable animal model for the study of soft palate myogenesis; (2) there were no discernible morphologic differences between the soft palate muscles in cleft and noncleft A/Jax mice when viewed under light microscopy; (3) the soft palate and related muscles were identifiable as muscle fields, in both the cleft and noncleft fetuses, as early as gestational day 15 and as specific muscles at gestational day 18; (4) in both the cleft and noncleft A/Jax fetuses, the soft palate muscles appeared in a sequential anatomic fashion (the palatine aponeurosis appeared first, next the tensor palatini, and then the levator palatini muscles); and (5) in the cleft palate fetuses, both pterygoid plates were angulated and displaced laterally.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
P. Falkingham ◽  
R. Rae

AbstractMany parasites and hosts are embroiled in an on-going arms race that affects the evolution of each participant. One such battle is between parasitic nematodes and terrestrial gastropods which have co-evolved for 90–130 MY. Recently, snails have been shown to encase and kill invading nematodes using their shell as a defence mechanism. However, there is remarkably little known about this process in terms of understanding where, when and how nematodes are fixed within the shell. Also there has never been any attempt to observe this process using methods other than light microscopy. Therefore, we used micro CT scanning of a Cepaea nemoralis shell (a common host for nematodes) to 3D visualise encased nematode parasites and quantify morphological parameters. By taking this approach future studies could use micro CT scanning of fossil shells in conchology collections to understand nematode/snail co-evolution.


Author(s):  
Donald C. Sun ◽  
Richard E. Crang

The compound eyes of wild type Drosophila melanogaster normally contain two pigments—ommochrome (brown) and drosopterine (red). However, sepiapterine (yellow), which is a biochemical precursor of drosopterine, is present in several mutant flies instead of drosopterine—or in addition to it. Transmission electron microscope observations reported here reveal fine structural differences between the pigment granules at various times post-pupation in D. melanogaster wild type as well as the mutants sepia and clot.Eyes from pupae at 54, 72 and 90 hours post-pupation were fixed with glutaraldehyde and osmium tetroxide followed by dehydration and embedment in Epon 812. Alternate thin (50-70 nm) and thick (1-2 μ) sections from the embedded material were sectioned with an ultramicrotome for electron and light microscopy respectively.


Author(s):  
Nakazo Watari ◽  
Yasuaki Hotta ◽  
Yoshio Mabuchi

It is very useful if we can observe the identical cell elements within the same sections by light microscopy (LM), transmission electron microscopy (TEM) and/or scanning electron microscopy (SEM) sequentially, because, the cell fine structure can not be indicated by LM, while the color is; on the other hand, the cell fine structure can be very easily observed by EM, although its color properties may not. However, there is one problem in that LM requires thick sections of over 1 μm, while EM needs very thin sections of under 100 nm. Recently, we have developed a new method to observe the same cell elements within the same plastic sections using both light and transmission (conventional or high-voltage) electron microscopes.In this paper, we have developed two new observation methods for the identical cell elements within the same sections, both plastic-embedded and paraffin-embedded, using light microscopy, transmission electron microscopy and/or scanning electron microscopy (Fig. 1).


Author(s):  
C. T. Nightingale ◽  
S. E. Summers ◽  
T. P. Turnbull

The ease of operation of the scanning electron microscope has insured its wide application in medicine and industry. The micrographs are pictorial representations of surface topography obtained directly from the specimen. The need to replicate is eliminated. The great depth of field and the high resolving power provide far more information than light microscopy.


Author(s):  
Bruce Mackay

The broadest application of transmission electron microscopy (EM) in diagnostic medicine is the identification of tumors that cannot be classified by routine light microscopy. EM is useful in the evaluation of approximately 10% of human neoplasms, but the extent of its contribution varies considerably. It may provide a specific diagnosis that can not be reached by other means, but in contrast, the information obtained from ultrastructural study of some 10% of tumors does not significantly add to that available from light microscopy. Most cases fall somewhere between these two extremes: EM may correct a light microscopic diagnosis, or serve to narrow a differential diagnosis by excluding some of the possibilities considered by light microscopy. It is particularly important to correlate the EM findings with data from light microscopy, clinical examination, and other diagnostic procedures.


Author(s):  
Gladys Harrison

With the advent of the space age and the need to determine the requirements for a space cabin atmosphere, oxygen effects came into increased importance, even though these effects have been the subject of continuous research for many years. In fact, Priestly initiated oxygen research when in 1775 he published his results of isolating oxygen and described the effects of breathing it on himself and two mice, the only creatures to have had the “privilege” of breathing this “pure air”.Early studies had demonstrated the central nervous system effects at pressures above one atmosphere. Light microscopy revealed extensive damage to the lungs at one atmosphere. These changes which included perivascular and peribronchial edema, focal hemorrhage, rupture of the alveolar septa, and widespread edema, resulted in death of the animal in less than one week. The severity of the symptoms differed between species and was age dependent, with young animals being more resistant.


Author(s):  
Joseph E. Mazurkiewicz

Immunocytochemistry is a powerful investigative approach in which one of the most exacting examples of specificity, that of the reaction of an antibody with its antigen, isused to localize tissue and cell specific molecules in situ. Following the introduction of fluorescent labeled antibodies in T950, a large number of molecules of biological interest had been studied with light microscopy, especially antigens involved in the pathogenesis of some diseases. However, with advances in electron microscopy, newer methods were needed which could reveal these reactions at the ultrastructural level. An electron dense label that could be coupled to an antibody without the loss of immunologic activity was desired.


Author(s):  
E. S. Boatman ◽  
G. E. Kenny

Information concerning the morphology and replication of organism of the family Mycoplasmataceae remains, despite over 70 years of study, highly controversial. Due to their small size observations by light microscopy have not been rewarding. Furthermore, not only are these organisms extremely pleomorphic but their morphology also changes according to growth phase. This study deals with the morphological aspects of M. pneumoniae strain 3546 in relation to growth, interaction with HeLa cells and possible mechanisms of replication.The organisms were grown aerobically at 37°C in a soy peptone yeast dialysate medium supplemented with 12% gamma-globulin free horse serum. The medium was buffered at pH 7.3 with TES [N-tris (hyroxymethyl) methyl-2-aminoethane sulfonic acid] at 10mM concentration. The inoculum, an actively growing culture, was filtered through a 0.5 μm polycarbonate “nuclepore” filter to prevent transfer of all but the smallest aggregates. Growth was assessed at specific periods by colony counts and 800 ml samples of organisms were fixed in situ with 2.5% glutaraldehyde for 3 hrs. at 4°C. Washed cells for sectioning were post-fixed in 0.8% OSO4 in veronal-acetate buffer pH 6.1 for 1 hr. at 21°C. HeLa cells were infected with a filtered inoculum of M. pneumoniae and incubated for 9 days in Leighton tubes with coverslips. The cells were then removed and processed for electron microscopy.


Sign in / Sign up

Export Citation Format

Share Document