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1

The influence of factors on baculovirus / insect cell system productivity

100%
Olejnik A., Grajek W.
Biotechnologia
|
2003
|
issue 1
158-175
EN
The baculovirus expression vector system (BEVS) is a powerful tool for the heterologous protein production. The productivity of BEVS depends on: insect cell lines and their growth parameters, medium composition, multiplicity of infection (MOI), time of infection (TOI), quality of viral inoculum and scale of cultivation. The factors influencing foreign gene expression level in BEVS ? were the subject of the presented review.
2

Ultrastructure and transovarial transmission of endosymbiotic microorganisms in Palaeococcus fuscipennis (Burmeister) (Insecta, Hemiptera, Coccinea: Monophlebidae)

100%
Szklarzewicz T., Kedra K., Niznik S.
Folia Biologica
|
2006
|
vol. 54
|
issue 1-2
61-67
EN
Ovaries of Palaeococcus fuscipennis (Burmeister) are accompanied by large organs termed bacteriomes which are composed of large cells termed bacteriocytes. Each bacteriocyte is surrounded with small epithelial cells. The bacteriocyte cytoplasm is tightly packed with pleomorphic bacteria, whereas in epithelial cells small coccoid microorganisms are present. The number of coccoid bacteria is significantly lower than pleomorphic bacteria. The ovarioles containing choriogenic oocytes are invaded both by pleomorphic as well by coccoid bacteria. Microorganisms traverse the follicular epithelium and enter the perivitelline space. During advanced choriogenesis, endosymbionts are accumulated in the deep depression of the oocyte. Bacteria do not enter the ooplasm until the end of oocyte growth.
3

Biotechnology of insect cell tissue culture

100%
Olejnik A., Grajek W.
Biotechnologia
|
2003
|
issue 1
176-192
EN
The commercial exploitation of the baculovirus expression system for heterologous protein or biopesticides production requires an efficient large-scale cultivation method. This review summarized recent developments concerning the scale-up of insect cell culture and baculovirus gene expression. We described novel bioreactor systems (stirred tank bioreactor, bioreactor airlift and cell-lift, membrane bioreactor), culture modes (batch, fed-batch, continuous) and different strategies used for cell cultivation and baculovirus replication.
4

The use of Bacillus thuringiensis in plant protection: prospects and limitations

88%
Malinowski H.
Biotechnologia
|
2000
|
issue 3
81-92
EN
Taking into account the protection of natural environment, it may be expected that the use of Bacillus thuringiensis toxins to control pest insects will be increased. It results from the discovery of novel toxins with different activity spectra and from the creation of more active toxins with the use of genetic engeeniering techniques. Besides, the introduction of transgenic plants such as cotton, potato, tomato, tobacco and others producing the bacterial toxins against more important species of pest insects will significantly reduce the application of chemical insecticides. The possibility of resistance development in insects poses a great threat to the above strategy. The better recognition of biochemical, physiological and genetical mechanisms of resistance to B. thuringiensis toxins will allow to devise a strategy for delaying jnsects resistance. The general principles of this strategy are similar to those used in the case of chemical insecticides and involve the rational application of B. thuringiensis toxins and their rotation with other insecticides.
5

Structure and development of ovaries in the weevil, Anthonomus pomorum (Coleoptera, Polyphaga). II. Germ cells of the trophic chamber

88%
Swiatek P.
Folia Biologica
|
2002
|
vol. 50
|
issue 3-4
153-163
EN
The analysis of the germ cell cluster formation in Anthonomus pomorum (Coleoptera, Polyphaga, Curculionidae) has revealed that both linear and branched clones of cystocytes occur in the pupa stage. In the branched clones a poorly developed polyfusome is formed and cystocytes with maximally 3 intercellular bridges were found. In the linear clones the polyfusomes are absent. Further divisions of cystocytes produce exclusively linearly arranged cells. Just after metamorphosis (Imago-A stage), the process of the germ cell membrane reduction starts. Only 2 groups of cells retain cell membranes: i.e the most anteriorly localized group of cystocytes and the posteriorly located presumptive oocytes. The former cells divide mitotically during the summer. As a result an anterior-posterior gradient of the syncytialization process arises in the Imago-B stage (females preparing for hibernation). In the sexually mature females (Imago-C) the trophic chamber consists of a huge syncytial area with numerous nurse cell nuclei embedded in a common cytoplasm, and posteriorly located young oocytes surrounded by prefollicular cells. In the light of recent hypothesis concerning the germ cell cluster formation and telotrophy anagenesis in Polyphaga the significance of the presented results is discussed.
6

The ovary of Neotituria kongosana (Hemiptera, Cicadomorpha: Ledridae). Ultrastructure of the tropharium and terminal filamen

88%
Lupa B., Kim J.-K., Bilinski S. M.
Folia Biologica
|
1999
|
vol. 47
|
issue 3-4
123-130
EN
Each of the 2 ovaries of Neotituria kongosana consists of 7 telotrophic ovarioles. Within the ovariole, the terminal filament, germarium, vitellarium, and pedicel can be distinguished. The terminal filaments are composed of disc-shaped basal cells and elongated apical cells, oriented parallel to the long ovariole axis. The apical and lateral aspects of the tropharium are encompassed by a single layer of somatic cells termed inner sheath cells. These cells are diversified into larger apical inner sheath cells (AISC) and much smaller lateral inner sheath cells (LISC). The tropharium is filled with numerous individual trophocytes (= nurse cells). All the trophocytes are surrounded by complete plasma membranes and are joined to a centrally located trophic core by means of narrow cytoplasmic extensions, termed trophic processes. The terminal filament is separated from the rest of the ovariole by a relatively solid transverse septum. It is suggested that the material constituting the septum is synthesized by 2 types of cell, namely the AISC and the basal cells of the terminal filament. Anagenesis of hemipteran ovarioles is discussed in relation to the findings presented.
7

Specific allergen induced motility of peripheral blood mononuclear cells and polymorphonuclear leukocytes in insect sting allergy

88%
Zak-Nejmark T., Malolepszy J., Jutel M., Nittner-Marszalska M.
|
|
vol. 40
|
issue 2
107-111
EN
The motility of perpheral blood mononuclear cells (MNC) and polymorphoxnuclear (PMN) leukocytes form normal and bee venom allergic subjects was investigated by a modified Boyden micropore filter method. The study comprised MNC locomotion in bee venom and gradients and PMN locomotion in bee venom and fMLP gradients. We demonstrated statistically significant increase in MNC and PMN motility towards bee venom in allergic patients group. This effect disappeared after the preincubation of MNC with anti-human IgE antiboidies. We observed no such effect in PMN leukocytes. Increased MNC motility in histamine gradient was observed only in control subjects group. Similarily significant increase in PMN locomotion towards fMLP was found in both allergic and control subjects. The results here demonstrated suggest that a specific allergen might be a chemoattractant for peripheral blood MNC and PMN leukocytes from atopics and could be capable to induce non-infectious inflammatory reactions as a result of its interaction with these sensitive cells.
8

Exoproteinases of the type A in pathogenesis of insect bacterial diseases

88%
Andrejko M.
Folia Biologica
|
1999
|
vol. 47
|
issue 3-4
135-141
EN
Immune inhibitors produced in infected larvae of Galleria mellonella by such entomopathogens as Pseudomonas aeruginosa, Serratia marcescens and Heterorhabditis bacteriophora effectively blocked in vitro bactericidal activity of insect haemolymph against Escherichia coli D31, both in Galleria mellonella and Pieris brassicae pupae previously vaccinated with Enterobacter cloacae. Even at a trace concentration, the extracellular proteinases, by proteolytic degradation, totally destroyed the activity of cecropin peptides from Galleria and cecropin-like and attacin-family proteins from Pieris, but no ability to destroy antibacterial activity was shown by extracts obtained from Galleria larvae killed by massive doses of bacterial saprophytes. It is suggested that by blocking antibacterial immune response of the host, the proteinases help the bacteria to multiply in the haemolymph, thus they could be considered an important factor in the pathogenesis of bacterial diseases of insects.
9

Structure of ovaries and oogenesis in Corydalidae and Chauliodidae (Insecta, Megaloptera). I. Architecture of adult ovarioles and previtellogenesis

88%
Szymanska B., Kubrakiewicz J., Jankowska W., Bilinski S. M.
Folia Biologica
|
2001
|
vol. 49
|
issue 1-2
91-97
EN
The results of histological and EM studies on the ovaries of three representatives of Megaloptera: Chauliodes pectinicornis, Nigronia fasciata (Chauliodidae), and Corydalus peruvianus Corydalidae) are presented. It is shown that the ovaries of all 3 investigated species are panoistic (secondary panoistic, = neopanoistic) and consist of numerous (more than a hundred) ovarioles that are differentiated into 3 well-defined regions: the terminal filament, the germarium, and the vitellarium. The germaria of adult females are apparently non-functional and contain germ and somatic cells in various stages of degeneration. The vitellaria are composed of 12 ? 15 developing ovarian follicles (= oocytes surrounded by follicular cells) in a linear arrangement. In adult females these follicles can be classified into early previtellogenic, late previtellogenic, vitellogenic, and choriogenic. During early previtellogenesis oocyte nuclei (= germinal vesicles) contain single nucleolar masses. Histochemical analyses indicate that within the masses DNA as well as AgNOR proteins are present. During subsequent stages of the previtellogenic growth nucleolar masses gradually break down into smaller aggregations of coarse granular material, i.e. multiple nucleoli. In chauliodids the nucleoli are distributed evenly throughout the nucleoplasm while in the corydalid, C. peruvianus, they form a characteristic ring. The presented results are discussed in a phylogenetic context.
10

Microsporidia infect the Liophloeus lentus (Insecta, Coleoptera) ovarioles, developing oocytes and eggs.

88%
Swiatek P., Gorkiewicz T.
Folia Biologica
|
2006
|
vol. 54
|
issue 1-2
61-67
EN
In the ovarioles of Liophloeus lentus (Insecta, Coleoptera, Curculionidae) two types of bacteria and parasitic microorganisms belonging to Microsporidia have been found. This study shows that the different microsporidian life stages (meronts, sporonts, sporoblasts and spores) infect the outer ovariole sheath, trophic chambers, follicular cells, late previtellogenic and vitellogenic oocytes and eggs. In trophic chambers the parasites are very abundant and are distributed unevenly, i.e. their large mass occupies the syncytial cytoplasm between the nurse cell nuclei, whereas the neck region of the trophic chamber (which houses young oocytes, prefollicular cells and trophic cords) is almost free of parasites. The developing oocytes and eggs contain a lower number of parasites which are usually distributed in the cortical ooplasm. The gross morphology of the ovaries is similar in infected and non-infected specimens. Similarly, the presence of a parasite seems to not disturb the course of oogensis. The only difference was found in the ultrastructure of mitochondria in young previtellogenic oocytes. In the infected females they are unusual i.e. bigger and spherical with tubullar cristae, whereas in the non-infected insects they are elongated and have lamellar cristae. As oogenesis progresses the unusual mitochondria rapidly change their morphology and become similar to the mitochondria in non-infected females. Taking into account the distribution of parasites within the ovarioles, it is suggested that they infect growing oocytes via outer ovariole sheath and follicular epithelium rather than via trophic cords.
11

Structure of ovaries and formation of egg envelopes in the stonefly, Leuctra autumnalis Aubert, 1948 (Plecoptera: Leuctridae). Ultrastructural studies

88%
Poprawa I., Baran A., Rosciszewska E.
Folia Biologica
|
2002
|
vol. 50
|
issue 1-2
29-38
EN
The investigation of ovaries and the formation of egg envelopes of the stonefly Leuctra autumnalis was carried out with light and transmission electron microscopes. The ovary of the studied species is paired and consists of several dozen panoistic ovarioles opening individually to the oviduct. The process of egg capsule formation already begins in previtellogenesis. At this time the follicular cells secrete precursors of the vitelline envelope. Analysis of the presented data suggests that the oocyte itself also takes part in the formation of the vitelline envelope during late vitellogenesis. Simultaneously, the follicular cells produce precursors of further layers of the egg capsule, i.e. two-layered chorion and extrachorion, consisting of two gelatinous layers and a flocculent one. The completely developed capsule contains channels, probably micropylar ones.
12

Vanilloid receptors - comparison of structure and functions in Mammals and Invertebrates

88%
Olszewska J.
Folia Biologica
|
2010
|
vol. 58
|
issue 1-2
1-7
EN
The vanilliod receptor subfamily belongs to the transient receptor potential family of ion channels. Vanilloid receptors are calcium-permeable channels highly expressed in many different cells, both excitable and nonexcitable, in invertebrates (nematodes, insects) and vertebrates (mammals). These receptors are sensitive to a wide range of stimuli (chemical, mechanical, osmotic and temperature) that often activate the same channel. This review focuses on recent information, both bibliographic and experimental evidence of the author, concerning the structure and functions of vanilloid receptors, especially those connected with thermoregulation.
13

Structure and development of ovaries in the weevil, Anthonomus pomorum (Coleoptera, Polyphaga). I. Somatic tissues of the trophic chamber

88%
Swiatek P.
Folia Biologica
|
2001
|
vol. 49
|
issue 3-4
215-224
EN
In developing ovarioles of Anthonomus pomorum (Coleoptera, Polyphaga, Curculionidae) the trophic chambers (tropharia) are relatively large and consist of clusters (clones) of germ cells and various somatic tissues. Each ovariole is enclosed within an outer epithelial sheath (tunica externa). Throughout the pupal phase, the growth of this sheath is accelerated and precedes the development of the rest of the ovariole. As a result, the epithelial sheath proliferates anteriorly and forms an elongated ?sleeve? that during the later stages of development becomes gradually filled by the growing tropharium. In the early pupal stage, a few terminal filament cells are observed in contact with the anterior end of the tropharium. These cells are separated from the rest of the trophic chamber by a transverse septum, which maintains continuity with the basal lamina. Beneath the basal lamina there is a layer of inner sheath cells, whereas inside the tropharium there are interstitial cells. These two types of cell differ morphologically in a mature ovary but they retain, until the end of the imago-B stage, a similar ultrastructure testifying to their common origin. At the posterior end of the tropharium, from the imago-B stage on, many young oocytes, surrounded by prefollicular cells, are observed. This is the so-called neck region of the tropharium. Extraction with Triton X-100 detergent showed that in a mature trophic chamber there are only individual microtubules arranged along the projections of interstitial cells. This indicates that the cytoskeleton elements (microfilaments and microtubules) participate only to a very limited extent in the spatial organisation of the tropharium in A. pomorum.
14

Beauvericin cytotoxicity to the invertebrate cell line SF-9

75%
Calo L., Fornelli F., Nenna S., Tursi A., Caiaffa M. F., Macchia L.
Journal of Applied Genetics
|
2003
|
vol. 44
|
issue 4
515-520
EN
The cyclic hexadepsipeptide beauvericin, initially known as a secondary metabolite produced by the entomopathogenic fungus Beauveria bassiana and toxic to Artemia salina larvae, has been more recently recognized as an important mycotoxin synthesized by a number of Fusarium strains, which parasite maize, wheat and rice. Therefore, this mycotoxin may enter the food chain, causing yet unknown effects to the health of both domestic animals and humans. The cytotoxic effects of beauvericin on mammalian cells have been studied. We investigated the cytotoxicity of this compound in an in vitro invertebrate model, viz. the insect cell line SF-9 (immortalized pupal ovarian cells of the lepidopter Spodoptera frugiperda). Cultures of SF-9 cells in the stationary phase were exposed to beauvericin at concentrations ranging from 100 nM to 300 M, for different periods of time (from 30? to 120 h). The effects on cell viability were assessed by the trypan blue exclusion method. After 4 h of incubation no significant decrease in cell viability was recorded in SF-9 cell cultures exposed to low concentrations of beauvericin, i.e. 100 nM and 300 nM. However, a slight decrease in viability (3.9%) was seen already in cells exposed to the mycotoxin at the 1 M concentration. This effect became gradually more evident at higher concentrations ( 28% at 30 M, 50% at 100 M, 68% at 300 M). An even more pronounced reduction in cell viability was observed after a 24 h exposure. Under these conditions, 1 M beauvericin caused an approx. 10% decrease in the number of viable cells, which became more significant at higher concentrations 23% at 3 M, 47% at 10 M, 65% at 30 M, 90% at 100 M, 99% at 300 M). Therefore, the 50% cytotoxic concentrations (CC50) at 4 h and 24 h could be estimated as 85 M and 10 M, respectively. In time-course experiments, no effect of beauvericin (30 M) on cell viability could be seen after exposure for periods of time as long as 30?, 1 h and 2 h, respectively. In contrast, when SF-9 cells were exposed to the mycotoxin for longer periods of time, from 8 h to 120 h, we recorded a strong cytotoxic effect already in the low micromolar concentration range. Thus, the CC50 after both 72 h and 120 h exposure times was assessed as 2.5 M. Higher concentrations caused a virtually 100% cell death. The data collected suggest that beauvericin exerts a substantial dose- and time-dependent cytotoxic effect on invertebrate cells, comparable to the effects described in mammalian cells.
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