Preserving Electronic Theses through the MetaArchive network

In the recent years most libraries have focused on mass digitization programs and keeping electronic born documents, showing and organizing them in a repository. While those repositories have evolved to a much more manageable systems focusing on the user expectations and introducing web 2.0 tools, digital preservation is still in the to-do list of most of them. There is quite a lot of studies focused on preservation and some complex models exist, unfortunately, very few practical systems are running and its quite difficult for a library to get involved in a solution already tested by others. The CBUC (Consortium of University Catalan Libraries) runs TDX, an ETD repository now keeping more than 10.000 full text thesis from any of the 12 university members. After 10 years running TDX a solid preservation system was needed to ensure every thesis would be kept as it was regardless what happens to the repository. The perfect solution was found in the MetaArchive cooperative, this is the effort of many insitutions to keep a copy of each other content through a newtwork using the LOCKSS software as a mechanism to keep track of any change. The presentation will shortly introduce what TDX and MetaArchive is but will, in a practical way, show how the LOCKSS network for presrervation works. Finally a summary of the benefits of the overall experience will be shown.

Cell Adhesion Peptide RGDSP and Laminin Support Proliferation and Migration of Postnatal Retinal Stem Cells in a 3D Hydrogel Culture System

Purpose: Retinal stem cells (RSCs) can be isolated from radial glia population of the newborn mouse retina (Angénieux et al., 2006). These RSCs have great capacity to renew and generate neurons including cells differentiated towards the photoreceptor lineage (Mehri-Soussi et al., 2006). However, our published results showed poor integration and survival rate after cell grafting into the retina. The uncontrollable environment of retina seems to be the problem. To bypass this, we are trying to generate hemi-retinal tissue in vitro that can be used for transplantation. Methods: Expanded RSCs were seeded in a mixture of poly-ethylene-glycol (PEG)-polymer-based hydrogels crosslinked by peptides that also serve as substrates for matrix metalloproteinases. Different doses of crosslinker peptides were tested. Several growth factors were studied to stimulate cell proliferation and differentiation. Results: Cells were trapped in hydrogels and cultured in the presence of FGF2 and EGF. Spherical cell clusters indicating proliferation appeared within several days, but there was no cell migration within the gel. We then added cell adhesion molecules integrin ligand RGDSP, or laminin, or a combination of both, into the gel. Cells grown with laminin showed the best proliferation. Cells grown with RGDSP proliferated a few times and then started to spread out. Cells grown with the combination of RGDSP and laminin showed better proliferation than with RGDSP alone and larger spread-outs than with laminin alone. After stimulations with first FGF2 and EGF, and then only FGF2, some cells showed neuronal morphology after 2 weeks. The neuronal population was assessed by the presence of neuronal marker b-tubulin-III. Glial cells were also present. Further characterizations are undergoing. Conclusions: RSC can grow and migrate in 3D hydrogel with the addition of FGF2, EGF, RGDSP and laminin. Further developments are necessary to form a homogenous tissue containing retinal cells.

Trypanosoma cruzi: Maintenance in Culture Modify Gene and Antigenic Expression of Metacyclic Trypomastigotes

In this study we examined whether the maintenance of Trypanosoma cruzi by long-time in axenic culture produces changes in gene expression and antigenic profiles. The studies were made with a Dm30L-clone from a low-virulent strain and a non-cloned virulent EP-strain of T. cruzi. Both parasites were maintained, for at least seven years, by successive alternate passage triatomine/mouse (triatomine condition), or by serial passage in axenic medium (culture condition). The comparison of the [35S]methionine metabolic labeling products of virulent and non-virulent parasites by 2D-SDS-PAGE, clearly indicates that the expression of metacyclic trypomastigotes (but not of epimastigotes) proteins have been altered by laboratory maintenance conditions. Western blot analysis of EP and Dm30L-epimastigotes using a serum anti-epimastigotes revealed that although most of antigens are conserved, four antigens are characteristics of triatomine condition parasites and three other are characteristics of culture condition parasites. Anti-metacyclics serum revealed significative differences in EP- and Dm30L-metacyclic trypomastigotes from triatomine condition. However, avirulent metacyclic forms were antigenically very similar. These results suggest that besides a possible selection of avirulent subpopulation from T. cruzi strains genetically heterogeneous when maintained by long time in axenic culture, changes in virulence might be due to post-translational modifications of the antigens induced by the absence of the natural alternability (vertebrate-invertebrate) in the life-cycle of T. cruzi

Cholinergic neurons of fetal rat telencephalon in aggregating cell culture respond to NGF as well as to protein kinase C-activating tumor promoters.

Serum-free aggregating cell cultures of fetal rat telencephalon treated with the potent tumor promoter phorbol 12-myristate 13-acetate (PMA) showed a dose-dependent, persistent stimulation of the enzymes choline acetyltransferase (ChAT), glutamic acid decarboxylase and glutamine synthetase. After elimination of the proliferating cells by treatment of the cultures with Ara-C (0.4 microM) only the cholinergic marker enzyme, ChAT, could be stimulated by tumor promoters. The non-promoting phorbol ester, 4 alpha-phorbol 12,13-didecanoate proved to be inactive in these cultures, whereas the potent non-phorbol tumor promoter, mezerein, produced an even greater stimulatory effect than PMA. Since PMA and mezerein are potent and specific activators of protein kinase C, the present results suggest a role for this second messenger in the development of cholinergic telencephalon neurons. Stimulation of ChAT required prolonged exposure (48 h) of the cultures to PMA and the responsiveness of the cholinergic neurons to the tumor promoters decreased with progressive cellular maturation. The cholinergic telencephalon neurons showed the same pattern of responsiveness for tumor promoters as for nerve growth factor (NGF). However, the combined treatment with NGF and either PMA or mezerein produced an additive stimulatory effect, suggesting somewhat different mechanisms of action.

Sensitivity of a Vacuum Aspiratory Culture Technique for Diagnosis of Localized Cutaneous Leishmaniasis in an Endemic Area of Leishmania (Viannia) braziliensis Transmission

Sixty eight patients with localized cutaneous leishmaniasis from an area with Leishmania (Viannia) braziliensis transmission had cultures performed with a modified Marzochi´s vacuum aspiratory puncture technique to establish sensitivity and contamination rate with this new method. Overall sensitivity of three aspirates was 47.1%; (CI95% 39.4; 59.4) significantly greater than the sensitivity of a single one aspirate. Fungal contamination was observed in 6/204 (2.9%) inoculated culture tubes. We recommend that this useful technique should be adopted as routine for primary isolation of L. (V.) braziliensis from localized cutaneous ulcers.

Development and growth of the early juveniles of the spider crab Maja squinado (Brachyura: Majoidea) in an individual culture system

The spider crab Maja squinado is an endangered Mediterranean species; therefore, culturing it successfully is essential for developing restocking programs. The survival, growth and development of post-larval stages (juvenile crabs, C1-C8) were studied using larvae obtained from adult individuals collected in the Catalan Sea. The juvenile crab stages were cultured individually from a megalopal stage using a semi-open recirculation system to obtain the precise growth data of each juvenile crab stage until C8. Development up to C8 at 20ºC lasted 154±10 days. Survival from C1 to C8 was 5.8 %. Moult increment values in cephothoracic length were similar in all the crab stages (21-35 %). Intermoult duration (9±1 in C1-C2 to 51±8 days in C7-C8) increased sharply from juvenile stage 5. Males and females can be distinguished from C4 based on sexual dimorphism in the pleopods and the presence of gonopores. The allometric growth of the pleon is sex-dependent from C4, with females showing positive allometry and males isometric growth. The juvenile growth rate was lower compared with that of the previously studied Atlantic species Maja brachydactyla.

Lipids shed into the culture medium by trypomastigotes of Trypanosoma cruzi

Trypomastigote forms of Trypanosoma cruzi were metabolically labeled with [14C]-ethanolamine and [3H]-palmitic acid. Lipids shed to the culture medium were analyzed and compared with the parasite components. Phosphatidylcholine and lysophosphatidylcholine accounted for 53% of the total incorporated precursor. Interestingly, phosphatidylethanolamine and its lyso derivative lysophosphatidylethanolamine, although present in significant amounts in the parasites, could not be detected in the shed material. Shed lipids were highly enriched in the desaturated fatty acids C16:1 and C18:1 when compared to the total fatty acid pool isolated from the parasites.

Changing the Culture (PDF 485 KB)

Infection Control Nursing in Northern Ireland

Primary care at Swiss universities--current state and perspective.

BACKGROUND: There is increasing evidence that a strong primary care is a cornerstone of an efficient health care system. But Switzerland is facing a shortage of primary care physicians (PCPs). This pushed the Federal Council of Switzerland to introduce a multifaceted political programme to strengthen the position of primary care, including its academic role. The aim of this paper is to provide a comprehensive overview of the situation of academic primary care at the five Swiss universities by the end of year 2012. RESULTS: Although primary care teaching activities have a long tradition at the five Swiss universities with activities starting in the beginning of the 1980ies; the academic institutes of primary care were only established in recent years (2005 - 2009). Only one of them has an established chair. Human and financial resources vary substantially. At all universities a broad variety of courses and lectures are offered, including teaching in private primary care practices with 1331 PCPs involved. Regarding research, differences among the institutes are tremendous, mainly caused by entirely different human resources and skills. CONCLUSION: So far, the activities of the existing institutes at the Swiss Universities are mainly focused on teaching. However, for a complete academic institutionalization as well as an increased acceptance and attractiveness, more research activities are needed. In addition to an adequate basic funding of research positions, competitive research grants have to be created to establish a specialty-specific research culture.

Quantification, self-renewal, and genetic tracing of FL1+ tumor-initiating cells in a large cohort of human gliomas.

Evidence has emerged that the initiation and growth of gliomas is sustained by a subpopulation of cancer-initiating cells (CICs). Because of the difficulty of using markers to tag CICs in gliomas, we have previously exploited more robust phenotypic characteristics, including a specific morphology and intrincic autofluorescence, to identify and isolate a subpopulation of glioma CICs, called FL1(+). The objective of this study was to further validate our method in a large cohort of human glioma and a mouse model of glioma. Seventy-four human gliomas of all grades and the GFAP-V(12)HA-ras B8 mouse model were analyzed for in vitro self-renewal capacity and their content of FL1(+). Nonneoplastic brain tissue and embryonic mouse brain were used as control. Genetic traceability along passages was assessed with microsatellite analysis. We found that FL1(+) cells from low-grade gliomas and from control nonneoplasic brain tissue show a lower level of autofluorescence and undergo a restricted number of cell divisions before dying in culture. In contrast, we found that FL1(+) cells derived from many but not all high-grade gliomas acquire high levels of autofluorescence and can be propagated in long-term cultures. Moreover, FL1(+) cells show a remarkable traceability over time in vitro and in vivo. Our results show that FL1(+) cells can be found in all specimens of a large cohort of human gliomas of different grades and in a model of genetically induced mouse glioma as well as nonneoplastic brain. However, their self-renewal capacity is variable and seems to be dependent on the tumor grade.

Oviposition Attractancy of Bacterial Culture Filtrates: response of Culex quinquefasciatus

Oviposition attractants could be used for monitoring as well as controlling mosquitoes by attracting them to lay eggs at chosen sites. In the present study, culture filtrates of seven bacterial species were tested for their attractancy against gravid females of Culex quinquefasciatus. When their oviposition active indices (OAI) were studied, the culture filtrates of Bacillus cereus and Pseudomonas fluorescens exhibited oviposition attractancy (OAI = >0.3) at 100 ppm and the OAI were respectively 0.70 and 0.47. Culture filtrates of B. thuringiensis var. israelensis (wild type), B. t. var. israelensis (mutant) and B. sphaericus showed attractancy at 2000 ppm with OAI of respectively 0.71, 0.59 and 0.68. However, the OAI of B. megaterium as well as Azospirillum brasilense was 0.13 (at 2000 ppm), which was less than 0.3 required to be considered them as attractants. When the oviposition attractancy of the bacterial culture filtrates were compared with that of a known oviposition attractant, p-cresol (at 10 ppm), the culture filtrates of B. t. var. israelensis (wild type) and B. cereus were found to be more active than p-cresol, respectively with 64.2 and 54.3% oviposition.

In Bacillus subtilis W23, the duet sigmaXsigmaM, two sigma factors of the extracytoplasmic function subfamily, are required for septum and wall synthesis under batch culture conditions.

The synthesis of poly(RboP), the main Bacillus subtilis W23 teichoic acid, is encoded by tarDF-tarABIJKL operons, the latter being controlled by two promoters designated PtarA-int and PtarA-ext. Analysis by lacZ fusions reveals that PtarA-int activity exhibits sharp increases at the beginning and end of the transition between exponential and stationary growth phase. As confirmed by mRNA quantification, these increases are mediated by ECF sigma factors sigmaX and sigmaM respectively. In liquid media, strain W23 sigX sigM double mutants experience serious difficulties in the transition and stationary growth phases. Inactivation of sigmaX- and sigmaM-controlled regulons, which precludes transcription from PtarA-int, leads to (i) delays in chromosome segregation and septation and (ii) a transient loss of up to 30% of the culture OD or lysis. However, specific inactivation of PtarA-int, leading mainly to a shortage of poly(RboP), does not affect growth while, nevertheless, interfering with normal septation, as revealed by electron microscopy. The different sigM transcription in strains W23 and 168 is discussed. In W23, expression of tarA and sigM, which is shown to control divIC, is inversely correlated with growth rate, suggesting that the sigM regulon is involved in the control of cell division.