147 research outputs found
Treatment volume of aedes albopictus with X rays generated from electrons
Irradiation is a common method used for sterilizing objects in several fields. In the entomology sector, insects are sterilized through irradiation and released in to the wild to sexually compete with the population at large reducing the chance for reproduction. This practice is the Sterile Insect Technique (SIT). Traditionally irradiation sources for SIT purpose are radioisotopes but many reasons compelled to getting efforts to develop other radiative technologies. Since gamma rays and electrons have similar sterilizing effects, the choice of source for SIT irradiation is based on considerations about penetration and environmental factors.
Gamma irradiators are usually simpler to operate, and less expensive, than electron accelerators, at least within the range of power required for SIT applications. Currently, the increased difficulties to manage and ship radioisotopes is being successfully resolved by the introduction of novel X-ray irradiators that enable a safer use of irradiator machines and procedures for SIT applications.
In the ENEA Frascati research center we developed irradiators for clinical radiotherapy consisting in a radiation converter from electrons to X-rays. Since X-rays penetrate deeper than the electrons from which they are generated, we used this technology in a configuration that delivers a uniform dose on large targets to irradiate insects for SIT aim.
In this topic, we gained practical experience working with Aedes albopictus, a mosquito vector of various tropical diseases such as dengue and zika. Several dosimetric studies have been conducted to achieve male sterility without affecting male mating competitiveness in comparison with untreated males. Lower doses have been also tested on an Ae. albopictus strain modified with the bacterium Wolbachia, which also determines male sterility, to sterilize the females eventually escaping the sexing procedures preliminary to the releases of the males
1983 Ruby Yearbook
A digitized copy of the 1983 Ruby, the Ursinus College yearbook.https://digitalcommons.ursinus.edu/ruby/1086/thumbnail.jp
Lung regions differently modulate bronchial branching development and extracellular matrix plays a role in regulating the development of chick embryo whole lung.
Normal branching development is dependent on the correlation between cells and extracellular matrix. In this interaction glycosaminoglycans, cytokines and growth factors play a fundamental role. In order to verify the distribution and influence of extracellular matrix and related enzymes on chick embryo lung development, 6 day-old whole lungs were maintained in vitro with testicular hyaluronidase, beta-N-acetyl-D-glucosaminidase and chondrotinase ABC or in linkage with apical, medial and caudal lung regions of 6-day development before and after enzyme treatment. In a separate lung region beta-N-acetyl-D-glucosaminidase and hyaluronidase were determined. Our data show that the whole lung cultures increase bronchial branching development when the medial region is admixed separately, while the separate apical or caudal regions or apical combined with caudal region do not affect bronchial branching development. The enzyme treatment of medial region prevents the branching development in associated whole lung. The bronchial branching development of whole lung cultured in medium containing the enzymes related to glycosaminoglycans turnover is significantly altered. In conclusion, these data show that the different influence of separate apical, medial, caudal lung regions on bronchial branching development is related to the extracellular matrix composition
Comparative proteomic analysis of two distinct stem-cell populations from human amniotic fluid
Glycosidases during chick embryo lung development and their colocalization with proteoglycans and growth factors
During development, the epithelial component of the lung goes through a complex orderly process of branching, following strict patterns of space and time. Proteoglycans, glycosaminoglycans and growth factors are fundamental components of the extracellular matrix and perform a key role in differentiative processes. The embryonic chick lung shows a specific glycosaminoglycan composition at different levels of branching and at different embryonic stages. Proteoglycan and glycosaminoglycan accumulation is the result of secretion, absorption and degradation processes. In this pathway, enzymes, such as glycosidases, growth factors and cytokines are involved. We examined the behaviour of glycosidases, such as Ăź-hexosaminidases (Ăź-N-acetyl-D-glucosaminidase, Ăź- N-acetyl-D-galactosaminidase), Ăź-glucuronidase and Ăź-galactosidase, during the development of the lung bud. Our data show that the activity of the enzymes is closely linked to the processes of epithelial proliferation, bronchial tubule lengthening and infiltration of the surrounding mesenchyme. The glycosaminoglycans colocalize with transforming growth factor Ăź2 and inter- leukin-1 in the basement membrane and in the mesenchymal areas where the epithelium grows, and are complementary to the presence of the glycosidases. In conclusion, the activity of these glycosidases is spatially and temporally programmed and favors the release of the factors and the events which they influence
Sertoli Cells as potential Pharmaceutical Carriers: uptake and stability
Sertoli cells (SC) have been used for their immunomodulatory properties in cell transplants (Emerich et al., 2003). Moreover, SC themselves may prevent immune rejection (Sipone et al., 2006) and possess a natural phagocytic activity: the latter may make them suitable as biocompatible drug delivery carriers. Porcine SC were loaded with PLA microspheres containing pharmaceutical agents (SC-MS). Phagocytosis was monitored over 24 hours; the uptake was measured by HPLC at fixed time points and followed up through 6 days. SC viability and morphology were monitored together with reactive oxygen species (ROS), DNA damage and parameters of SC functionality and immunomodulatory properties over time. A preliminary antibacterial activity was assessed in vitro. SC-MS were cryopreserved in liquid nitrogen and after plating underwent the same characterization. SC internalized drug loaded MS with an uptake rate of about 20% at 5 hours, that increased by 30% until day two. The uptake was stable up to 6 days with no differences in ROS, DNA damage, functional and immunomodulatory properties observed between control and loaded SC, even after cryopreservation/thawing. A spontaneous in vitro activity against pseudomonas strain, presented with SC alone, increased in presence of MS, and was maintained after cryoperservation. These results encourage further studies to understand the real potential of SC as drug delivery vehicles in trials in “in vivo” animal models
Isolation, characterization and microincapsulation of neonatal porcine Sertoli cells obtained from a specific pathogen free (SPF) herd
Porcine Sertoli cells (pSC) have been successfully employed as cell therapy in pre-clinical studies of several immune-based and chronic degenerative diseases. In order to prevent any transmission of infectious adventitious agents to the cells graft recipients, we have set up, according to our previously described method (Luca et al., 2007) pSC monolayers obtained from specific pathogen free (SPF) certified neonatal pigs, born in the unique SPF colony in Italy. pSC were assessed and characterized as far as viability, by ethidium bromide and fluorescein diacetate (EB/FD), MĂĽllerian inhibiting substance (AMH), and insulin-like 3 (INSL3), alpha-smooth muscle actin (ASMI) both by immunofluorescence (IF) and cytofluorimetric analysis (CA) were concerned. pSC were encapsulated in alginate microcapsules (MCpSC), with MCp- SC functional competence and biocompatibility being determined both in vitro, by AMH, inhibin B, TGF-beta, IGF-I secretion and in vivo in experimental animal models, respectively. Results demonstrated the high purity of our pSC monolayers (95% of AMH+cells), with negligible contamination by Leydig (2%) and peritubular cells (3%). Microencapsulation did not alter pSC viability and even after 4 months postimplantation, all the retrieved microcapsules retained morphology and function. In conclusion, we have uniquely obtained, from a SPF herd, highly purified, viable and functional pSC that might poten-tially apply to humans
Eliminating female Anopheles arabiensis by spiking blood meals with toxicants as a sex separation method in the context of the sterile insect technique
Cytoplasmic Incompatibility as a Means of Controlling Culex pipiens quinquefasciatus Mosquito in the Islands of the South-Western Indian Ocean
The use of the bacterium Wolbachia is an attractive alternative method to control vector populations. In mosquitoes, as in members of the Culex pipiens complex, Wolbachia induces a form of embryonic lethality called cytoplasmic incompatibility, a sperm-egg incompatibility occurring when infected males mate either with uninfected females or with females infected with incompatible Wolbachia strain(s). Here we explore the feasibility of the Incompatible Insect Technique (IIT), a species-specific control approach in which field females are sterilized by inundative releases of incompatible males. We show that the Wolbachia wPip(Is) strain, naturally infecting Cx. p. pipiens mosquitoes from Turkey, is a good candidate to control Cx. p. quinquefasciatus populations on four islands of the south-western Indian Ocean (La RĂ©union, Mauritius, Grande Glorieuse and Mayotte). The wPip(Is) strain was introduced into the nuclear background of Cx. p. quinquefasciatus mosquitoes from La RĂ©union, leading to the LR[wPip(Is)] line. Total embryonic lethality was observed in crosses between LR[wPip(Is)] males and all tested field females from the four islands. Interestingly, most crosses involving LR[wPip(Is)] females and field males were also incompatible, which is expected to reduce the impact of any accidental release of LR[wPip(Is)] females. Cage experiments demonstrate that LR[wPip(Is)] males are equally competitive with La RĂ©union males resulting in demographic crash when LR[wPip(Is)] males were introduced into La RĂ©union laboratory cages. These results, together with the geographic isolation of the four south-western Indian Ocean islands and their limited land area, support the feasibility of an IIT program using LR[wPip(Is)] males and stimulate the implementation of field tests for a Cx. p. quinquefasciatus control strategy on these islands
Biological traits and Life table parameters A and B biotype of Bemisia tabaci (Genn.) on cotton and rapeseed
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