The anatomical, physiological, and behavioral characteristics of honey bees are affected by the season as well as division of labor. In this study, we examined the structure, ultrastructure, and gene expression of fat body cells in both long-lived winter and short-lived summer worker bees (the youngest stage of hive bees and forager bees). In contrast to hive bees, foragers and winter bees have a higher metabolism due to intensive muscle activity during their flight (foragers) or endothermic heat production (winter bees). These workers differ from hive bees in the biology of their mitochondria, peroxisomes, and lysosomes as well as in the expression of the genes involved in lipid, carbohydrate, amino acid metabolism, insulin, and TGF- β signaling. Additionally, the expression of genes related to phospholipid metabolism was higher in the hive bees. However, we found no differences between workers in the expression of genes controlling cell organelles, such as the Golgi apparatus, endoplasmic reticulum, ribosomes, nucleus, and vacuoles, as well as genes for DNA replication, cell cycle control, and autophagy. Furthermore, lysosomes, autophagic processes and lipofuscin particles were more frequently observed in winter bees using electron microscopy.

• Klíčová slova
• Cell ultrastructure, Fat body, Forager bees, Hive bees, Metabolism, Winter bees,
• MeSH
• exprese genu * MeSH
• roční období MeSH
• tukové těleso metabolismus   ultrastruktura   MeSH
• včely * genetika   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Examination in the scanning and the transmission electron microscope showed three morphologically and structurally different types of cells in the vitreous body of the healthy rabbit eye: 1. cells with numerous cytoplasm processes, whose high metabolic activity is represented by the presence of a large number of organelles and which are capable of synthesizing fibrillar material; 2. elongate cells with a flattened nucleus, with long, narrow cytoplasm processes arising from both their poles and with only a few organelles in their cytoplasm; 3. large spherical cells with structureless contents, whose nucleus and few organelles are situated below the cell membrane. The organized component of the intercellular matter of the rabbit vitreous body is composed of collagen fibrils with a very variable diameter (24-180 nm), The collagen fibrils form the basis of the three-dimensional skeleton of the intercellular matter of the vitreous body.

• MeSH
• králíci MeSH
• sklivec ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• králíci MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Ultrastructure of the fat body was studied in following castes and developmental stages of Prorhinotermes simplex: larvae of the first and the second instar, pseudergates, presoldiers, soldiers, nymphs, imagoes and mature ergatoid neotenic reproductives of both sexes. Fat body always consists of two principal cell types: adipocytes and urocytes. Adipocytes are characterized by a presence of large amounts of storage substances, namely lipid droplets, glycogen rosettes and proteins in the form of either biocrystals or vacuoles. Proportion of these components strongly varies during ontogeny. Adipocytes are equipped by a large central vacuole in which lipid droplets may resolve. Cytoplasm of urocytes contain glycogen rosettes and spherical or irregular concretions, other organelles are rare. Only adipocytes change their inner structure in the course of ontogeny: amount of glycogen decreases during the postembryonic development, it is the major kind of inclusion in the larvae but lacks in nymphs and imagoes; opposite trend is performed by lipids. The changes in protein content are less obvious but are explained and discussed. The total amount of triacylglycerols (TAGs) was found to be roughly 100microg in a pseudergate, 250microg in a nymph, and 30microg in a soldier. The most abundant fatty acids in TAGs are oleic (O), stearic (S), palmitic (P) and linoleic (L) acid. TAGs form a complex mixture with OOO, OPO, OLO and OOS being the most abundant isomers. Only negligible differences exist among the castes.

• MeSH
• buněčná inkluze chemie   ultrastruktura   MeSH
• cytoplazma ultrastruktura   MeSH
• glykogen analýza   MeSH
• hmyzí proteiny analýza   MeSH
• Isoptera chemie   cytologie   ultrastruktura   MeSH
• lipidy analýza   MeSH
• transmisní elektronová mikroskopie MeSH
• tukové buňky MeSH
• tukové těleso chemie   cytologie   ultrastruktura   MeSH
• vakuoly ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• glykogen MeSH
• hmyzí proteiny MeSH
• lipidy MeSH

The somatic cuticle of adult female Philometra obturans (Prenant, 1886) (Nematoda: Dracunculoidea) consists of five zones and an overlying prominent fuzzy epicuticle, closely adherent to the gill arterial wall of the host. The cuticle is fenestrated and infiltrated with electron-dense substances. It protrudes into the hypodermis in the form of numerous protuberances. The plasma membrane of the hypodermis forms prominent infoldings within the subcuticular region. Numerous endosomes bud off from the cuticle into the hypodermis. Glycogen deposits are present within the hypodermis and muscle cells. The muscle cells are well developed, polymyarian in number (up to 30 in each quadrant) and coelomyarian in shape. The body wall of adult female P. obturans reveals several ultrastructural features which are common to the members of Filarioidea.

• MeSH
• arterie parazitologie   MeSH
• Dracunculoidea metabolismus   ultrastruktura   MeSH
• Esocidae parazitologie   MeSH
• infekce hlísticemi řádu Spirurida parazitologie   veterinární   MeSH
• mikrotomie metody   MeSH
• nemoci ryb parazitologie   MeSH
• transmisní elektronová mikroskopie MeSH
• žábry krevní zásobení   parazitologie   MeSH
• zvířata MeSH
• Check Tag
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Scanning and transmission electron microscopic examinations of tissue-dwelling third-stage larvae of the nematode Cystidicoloides ephemeridarum from the intermediate host (Ephemera danica) were carried out with respect to the morphological changes in the body wall associated with the transfer from the intermediate to the definitive host. The ultrastructure of the cephalic end and zonation of the somatic cuticle of infective larvae basically correspond with those of adults. The somatic cuticle is composed of a fuzzy epicuticle, an outer and inner cortical zone, a median zone and a basal zone consisting of three subzones. Globular bodies are absent from the median zone of the infective larvae. The lateral hypodermal cords of the infective larvae are cellular, consisting of a median cell enclosed by two sublateral cells. The excretory canal is present within each of the lateral cord in both the infective and adult stages. Walls of the excretory canals contain Golgi-derived vesicles which communicate with the lumen of the canal. Large deposits of glycogen, suggesting anaerobic respiration, are present in the hypodermal cords and noncontractile parts of the muscle cells of the third-stage larvae within the intermediate host.

• MeSH
• larva patogenita   ultrastruktura   MeSH
• mikroskopie elektronová rastrovací MeSH
• Spirurida růst a vývoj   patogenita   ultrastruktura   MeSH
• světluškovití parazitologie   MeSH
• transmisní elektronová mikroskopie MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

In this study, we tested the hypothesis that a micro-serrated edge on the honey bee Apis mellifera stinger tip serves as a tool for more intensive crushing of cell membranes in the victim's tissues. This could have mechanical consequences as well as initiate metabolic pathways linked to cell membrane breakdown (e.g., production of biogenic amines). Accordingly, we found that hymenopteran species that use their stingers as an offensive or defensive weapon to do as much damage to the victim's body as possible had this cuticular microstructure. In parasitic hymenopterans, on the other hand, this structure was missing, as stingers are solely used to delicately transport venom to the victim's body in order to do little mechanical harm. We also demonstrated that the stinger lancets of the honey bee A. mellifera are living organs with sensilla innervated by sensory neurons and containing other essential tissues, rather than mere cuticular structures.

• Klíčová slova
• Hymenoptera, SEM, TEM, bee, nerve, sensilla, stinger microstructure, ultrastructure,
• Publikační typ
• časopisecké články MeSH

Acanthocephalans, intestinal parasites of vertebrates, are characterised by orders of magnitude higher metal accumulation than free-living organisms, but the mechanism of such effective metal accumulation is still unknown. The aim of our study was to gain new insights into the high-resolution localization of elements in the bodies of acanthocephalans, thus taking an initial step towards elucidating metal uptake and accumulation in organisms under real environmental conditions. For the first time, nanoscale secondary ion mass spectrometry (NanoSIMS) was used for high-resolution mapping of 12 elements (C, Ca, Cu, Fe, N, Na, O, P, Pb, S, Se, and Tl) in three selected body parts (trunk spines, inner part of the proboscis receptacle and inner surface of the tegument) of Dentitruncus truttae, a parasite of brown trout (Salmo trutta) from the Krka River in Croatia. In addition, the same body parts were examined using transmission electron microscopy (TEM) and correlated with NanoSIMS images. Metal concentrations determined using HR ICP-MS confirmed higher accumulation in D. truttae than in the fish intestine. The chemical composition of the acanthocephalan body showed the highest density of C, Ca, N, Na, O, S, as important and constitutive elements in living cells in all studied structures, while Fe was predominant among trace elements. In general, higher element density was found in trunk spines and tegument, as body structures responsible for substance absorption in parasites. The results obtained with NanoSIMS and TEM-NanoSIMS correlative imaging represent pilot data for mapping of elements at nanoscale resolution in the ultrastructure of various body parts of acanthocephalans and generally provide a contribution for further application of this technique in all parasite species.

• Klíčová slova
• Body ultrastructure, Chemical composition, Correlative imaging, Nanoscale secondary ion mass spectrometry, Thorny-headed worms, Transmission electron microscopy,
• MeSH
• Acanthocephala * MeSH
• kovy MeSH
• pstruh parazitologie   MeSH
• spektrometrie hmotnostní sekundárních iontů * MeSH
• střeva MeSH
• transmisní elektronová mikroskopie MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• kovy MeSH

Light, scanning and transmission electron microscope examinations of adult Cystidicoloides ephemeridarum nematodes, parasitic in the stomach of brown trout (Salmo trutta fario L.), revealed that the body wall is composed of a cuticle, a hypodermis and longitudinally oriented somatic musculature. The body cuticle is composed of a trilaminated epicuticle, an outer and inner cortical zone, a median zone with globular bodies and a basal zone consisting of three subzones. Massive cuticle in the three zones and an osmiophilic lining is present in the buccal capsule. Armament is absent both from the buccal capsule and the head end. The surface of the body is transversely striated with cortical annuli. The only specialized attachment devices of C. ephemeridarum are the flexible overlapping margins of the annuli which are elongated in the first third of the body. Together with the sucking pressure of the oesophagus, they seem to play a role in the penetration and mechanical damage of the host's tissue. The hypodermis appears to be syncytial. Up to 300 worms were present in the bolus of food consumed by the host, or attached by their head ends in the lamina epithelialis, which resulted in localized disruptions of the mucosal epithelium with no inflammation. Infection with C. ephemeridarum seems to be a temporary, season-dependent event of mild pathogenicity.

• MeSH
• elektronová mikroskopie MeSH
• infekce hlísticemi řádu Spirurida parazitologie   patologie   veterinární   MeSH
• mikroskopie elektronová rastrovací MeSH
• nemoci ryb parazitologie   patologie   MeSH
• pstruh parazitologie   MeSH
• Spirurida patogenita   ultrastruktura   MeSH
• žaludek parazitologie   patologie   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The midgut epithelia of the millipedes Polyxenus lagurus, Archispirostreptus gigas and Julus scandinavius were analyzed under light and transmission electron microscopies. In order to detect the proliferation of regenerative cells, labeling with BrdU and antibodies against phosphohistone H3 were employed. A tube-shaped midgut of three millipedes examined spreads along the entire length of the middle region of the body. The epithelium is composed of digestive, secretory and regenerative cells. The digestive cells are responsible for the accumulation of metals and the reserve material as well as the synthesis of substances, which are then secreted into the midgut lumen. The secretions are of three types - merocrine, apocrine and microapocrine. The oval or pear-like shaped secretory cells do not come into contact with the midgut lumen and represent the closed type of secretory cells. They possess many electron-dense granules (J. scandinavius) or electron-dense granules and electron-lucent vesicles (A. gigas, P. lagurus), which are accompanied by cisterns of the rough endoplasmic reticulum. The regenerative cells are distributed individually among the basal regions of the digestive cells. The proliferation and differentiation of regenerative cells into the digestive cells occurred in J. scandinavius and A. gigas, while these processes were not observed in P. lagurus. As a result of the mitotic division of regenerative cells, one of the newly formed cells fulfills the role of a regenerative cell, while the second one differentiates into a digestive cell. We concluded that regenerative cells play the role of unipotent midgut stem cells.

• Klíčová slova
• Digestive cells, Midgut epithelium, Millipedes, Regenerative cells, Secretory cells, Ultrastructure,
• MeSH
• členovci fyziologie   ultrastruktura   MeSH
• epitel metabolismus   ultrastruktura   MeSH
• kmenové buňky fyziologie   ultrastruktura   MeSH
• trávicí systém metabolismus   ultrastruktura   MeSH
• zvířata MeSH
• Check Tag
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• Geografické názvy
• Česká republika MeSH

• MeSH
• celotělové ozáření MeSH
• elektronová mikroskopie MeSH
• endotel účinky záření   ultrastruktura   MeSH
• kapiláry účinky záření   ultrastruktura   MeSH
• krysa rodu Rattus MeSH
• mozkový krevní oběh účinky záření   MeSH
• záření gama MeSH
• zvířata MeSH
• Check Tag
• krysa rodu Rattus MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH