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Direct ultrafast laser photoinscription of transparent materials is a powerful technique for the development of embedded 3D photonics. This is particularly adaptable for astrophotonic devices when a number of inputs are required. The process relies essentially on volume fabrication of waveguiding structures in flexible 3D designs and refractive index contrast parameters adjustable for specific spectral ranges. This enables 3D geometry and thus avoids in-plane crossings of waveguides that can induce losses and cross talk in multi-telescope beam combiners. The additional novel capability of the technique allows for the fabrication of high aspect ratio nanostructures nonperturbatively sampling the optical field. Combining ultrafast laser micro- and nanoprocessing with engineered beams, we present here results for the development of chip-sized silica glass integrated robust 3D three-telescope beam combiners in the near-IR range, as well as embedded diffraction gratings, for phase closure analysis and spectro-interferometry applications in astronomy.

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A buried straight waveguide perturbed periodically by six antennas composed of submicronic cylinder voids is entirely fabricated using ultrafast laser photoinscription. The light scattered from each antenna is oriented vertically and is detected by a short-wave IR camera bonded to the surface of the glass with no relay optics. The response of each antenna is analyzed using a wavelength tunable laser source and compared to simulated responses verifying the behavior of the antenna. These results show the good potential of the direct laser writing technique to realize monolithic embedded detectors by combining complex optical functions within a 3D design. A wavelength meter application with a spectral resolution of 150 pm is proposed to demonstrate this combination.

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BACKGROUND AND PURPOSE: We have reported that exposure to a diabetic intrauterine environment during pregnancy increases blood pressure in adult offspring, but the mechanisms involved are not completely understood. This study was designed to analyse a possible role of perivascular sympathetic and nitrergic innervation in the superior mesenteric artery (SMA) in this effect. EXPERIMENTAL APPROACH: Diabetes was induced in pregnant Wistar rats by a single injection of streptozotocin. Endothelium-denuded vascular rings from the offspring of control (O-CR) and diabetic rats (O-DR) were used. Vasomotor responses to electrical field stimulation (EFS), NA and the NO donor DEA-NO were studied. The expressions of neuronal NOS (nNOS) and phospho-nNOS (P-nNOS) and release of NA, ATP and NO were determined. Sympathetic and nitrergic nerve densities were analysed by immunofluorescence. KEY RESULTS: Blood pressure was higher in O-DR animals. EFS-induced vasoconstriction was greater in O-DR animals. This response was decreased by phentolamine more in O-DR animals than their controls. L-NAME increased EFS-induced vasoconstriction more strongly in O-DR than in O-CR segments. Vasomotor responses to NA or DEA-NO were not modified. NA, ATP and NO release was increased in segments from O-DR. nNOS expression was not modified, whereas P-nNOS expression was increased in O-DR. Sympathetic and nitrergic nerve densities were similar in both experimental groups. CONCLUSIONS AND IMPLICATIONS: The activity of sympathetic and nitrergic innervation is increased in SMA from O-DR animals. The net effect is an increase in EFS-induced contractions in these animals. These effects may contribute to the increased blood pressure observed in the offspring of diabetic rats.

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In mammalian cells, the calnexin/calreticulin chaperones play a key role in glycoprotein folding and its control within the endoplasmic reticulum (ER), by interacting with folding intermediates via their monoglucosylated glycans. This lectin activity has been mapped in mammalian calnexin/calreticulin chaperones to the central region, which is a highly conserved feature of calnexin/calreticulin molecules across species. The central domain has also been implicated in Ca(2+) binding, and it has been proposed to be involved in the regulation of calcium homeostasis in the ER. Herein, we show that although the Schizosaccharomyces pombe calnexin is essential for viability, cells lacking its 317-amino-acid highly conserved central region are viable under normal growth conditions. However, the central region appears to be necessary for optimal growth under high ER-stress, suggesting that this region is important under extreme folding situations (such as DTT and temperature). The minimal length of calnexin required for viability spans the C-terminal 123 residues. Furthermore, cells with the central domain of the protein deleted were affected in their morphology at 37 degrees C, probably due to a defect in cell wall synthesis, although these mutant cells exhibited the same calcium tolerance as wild-type cells at 30 degrees C.

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The association of newly synthesized glycoproteins with the ER molecular chaperones calnexin and immunoglobulin binding protein (BiP) has been well documented in a variety of higher eukaryotes. Here we report that Cnx1p, the calnexin homologue in Schizosaccharomyces pombe, associates with newly synthesized molecules of the secreted glycoprotein acid phosphatase. Unlike ligand binding to mammalian calnexin, glucose trimming and reglucosylation of acid phosphatase by UDP-Glc:glycoprotein glucosyltransferase were shown to be dispensable for its binding to Cnx1p. Thus, despite the essentiality of Cnx1p for S. pombe viability, the glucose trimming and reglucosylation cycle does not appear to be required for protein folding in the fission yeast. The association of core-glycosylated acid phosphatase with Cnx1p after exposure of cells to heat shock or to DTT was shown to be reversible. However, Cnx1p stably associated with unglycosylated acid phosphatase after treatment with the core-glycosylation inhibitor tunicamycin. BiP was found to coprecipitate with Cnx1p, under normal and stress conditions, and following inhibition of protein synthesis by cycloheximide. We postulate that Cnx1p and BiP are part of a complex that is involved in the folding of both core-glycosylated trimmed ligands and unglycosylated proteins.

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Certain viruses have evolved mechanisms to counteract innate immunity, a host response in which nuclear factor kappaB (NF-kappaB) transcription factors play a central role. African swine fever virus encodes a protein of 28.2 kDa containing ankyrin repeats similar to those of cellular IkappaB proteins, which are inhibitors of NF-kappaB. Transfection of the African swine fever virus IkappaB gene inhibited tumor necrosis factor- or phorbol ester-induced activation of kappaB- but not AP-1-driven reporter genes. Moreover, African swine fever virus IkappaB co-immunoprecipitated with p65 NF-kappaB, and the purified recombinant protein prevented the binding of p65-p50 NF-kappaB proteins to their target sequences in the DNA. NF-kappaB activation induced by tumor necrosis factor, as detected by mobility shift assays or by transfection of kappaB-driven reporter genes, is impaired in African swine fever virus-infected cells. These results indicate that the African swine fever virus IkappaB gene homologue interferes with NF-kappaB activation, likely representing a new mechanism to evade the immune response during viral infection.

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The objective of the present study was to determine the frequency of adverse drug reactions (ADRs) in intensive care units (ICUs) and to evaluate their effect on the length of stay. We performed a prospective study to detect ADRs in 420 patients hospitalised in 10 predetermined beds in the ICU of our hospital between the months of March and December 1996. While the patients were staying in the ICU, data was gathered regarding suspected ADRs and on different variables related to the length of stay. 96 different ADRs were detected in 85 of the 420 patients seen [20.2%, 95% confidence intervals (95% CI) 16.5 to 24.4]. The ADRs were most frequently caused by the following drugs: nitrates (n = 25), opiates (n = 21) and ultrashort-acting benzodiazepines (n = 10). Eight ADRs were severe, the suspected medication had to be discontinued in 51 cases and new drugs were necessary to manage the ADRs in 73 cases. The crude estimation of the effect of the number of ADRs performed with a bivariant regression model indicated that each ADR was related to a 2.38-day increase (95% CI 1.31 to 3.45) in the length of stay. Although this estimation was reduced to 1.76 days (95% CI 0.72 to 2.79), when other confounding variables associated with the length of stay were considered, it was still important.In conclusion, the ADRs were a significant clinical problem in the ICUs and were responsible for a significant increase in the length of stay.

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Previous attempts to produce active human Interleukin-2 (hIL-2) in E. coli have failed, due to its aggregation in the form of cytoplasmic inclusion bodies, and the inability of the protein to enter the periplasmic export pathway, when fused to bacterial signal sequences. We have reasoned that these limitations could be overcome by introducing changes in the signal sequence and/or in some hIL-2 residues, not critical for its biological activity; and proceeded to test this hypothesis using a phagemid vector carrying the pelB secretion signal sequence, and the filamentous phage display system. Deletion of the Pro +2 in hIL-2 led to the export of a correct size (processed) molecule to the bacterial periplasm of Su- cells by the phagemid vector. However, this was achieved under growth conditions that would not favor phage assembly in Su+ strains. Changing the hydrophobic core of the leader peptide reversed this situation and allowed phage assembly and display of a pIII/hIL-2 hybrid protein in TG1 cells. The phage-displayed hIL-2 is correctly folded, as judged by its ability to interact with a conformation-specific anti-hIL-2 monoclonal antibody, and maintains its biological activity when tested in a CTLL-2 cell proliferation assay. The changes introduced in hIL-2 and the signal sequence will make possible to use the powerful phage display technology for the selection of high-affinity variants from libraries of hIL-2 mutants.

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