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21.
Erbin is a recently described member of the LAP (leucine-rich repeat and PDZ domain) protein family. We used a C-terminally displayed phage peptide library to identify optimal ligands for the Erbin PDZ domain. Phage-selected peptides were type 1 PDZ ligands that bound with high affinity and specificity to the Erbin PDZ domain in vitro. These peptides most closely resembled the C-terminal PDZ domain-binding motifs of three p120-related catenins: delta-catenin, ARVCF, and p0071 (DSWV-COOH). Analysis of the interactions of the Erbin PDZ domain with synthetic peptides matching the C termini of ARVCF or delta-catenin also demonstrated specific high affinity binding. We characterized the interactions between the Erbin PDZ domain and both ARVCF and delta-catenin in vitro and in vivo. The Erbin PDZ domain co-localized and coprecipitated with ARVCF or delta-catenin complexed with beta-catenin and E/N-cadherin. Mutagenesis and peptide competition experiments showed that the association of Erbin with the cadherin-catenin complex was mediated by the interaction of its PDZ domain with the C-terminal PDZ domain-binding motifs (DSWV-COOH) of ARVCF and delta-catenin. Finally, we showed that endogenous delta-catenin and Erbin co-localized in and co-immunoprecipitated from neurons. These results suggest that delta-catenin and ARVCF may function to mediate the association of Erbin with the junctional cadherin-catenin complex. They also demonstrate that C-terminal phage-display technology can be used to predict physiologically relevant ligands for PDZ domains.  相似文献   
22.
While the long-distance movements of pelagic vertebrates are becoming known thanks to satellite telemetry, the factors determining their courses have hardly been investigated. We have analysed the effects of oceanographic factors on the post-nesting movements of three satellite-tracked leatherback turtles (Dermochelys coriacea) moving in the southwest Indian Ocean. By superimposing the turtle tracks on contemporaneous images of sea-surface temperatures and sea height anomalies, we show that currentrelated features dominate the shape of the reconstructed routes. After an initial offshore movement, turtles moved along straight routes when in the core of the current, or executed loops within eddies. Large parts of the routes were strikingly similar to those of surface drifters tracked in the same region. These findings document that long-lasting oceanic movements of marine turtles may be shaped by oceanic currents.  相似文献   
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24.
Solanum tuberosum plants were transformed with three genetic constructions expressing the Nicotiana tabacum AP24 osmotine, Phyllomedusa sauvagii dermaseptin and Gallus gallus lysozyme, and with a double-transgene construction expressing the AP24 and lysozyme sequences. Re-transformation of dermaseptin-transformed plants with the AP24/lysozyme construction allowed selection of plants simultaneously expressing the three transgenes. Potato lines expressing individual transgenes or double- and triple-transgene combinations were assayed for resistance to Erwinia carotovora using whole-plant and tuber infection assays. Resistance levels for both infection tests compared consistently for most potato lines and allowed selection of highly resistant phenotypes. Higher resistance levels were found in lines carrying the dermaseptin and lysozyme sequences, indicating that theses proteins are the major contributors to antibacterial activity. Similar results were obtained in tuber infection tests conducted with Streptomyces scabies. Plant lines showing the higher resistance to bacterial infections were challenged with Phytophthora infestans, Rhizoctonia solani and Fusarium solani. Considerable levels of resistance to each of these pathogens were evidenced employing semi-quantitative tests based in detached-leaf inoculation, fungal growth inhibition and in vitro plant inoculation. On the basis of these results, we propose that stacking of these transgenes is a promising approach to achieve resistance to both bacterial and fungal pathogens.  相似文献   
25.
Sessile colonies and motile hormogonia, the two main developmental stages in the life cycle of a Nostoc strain isolated from the endocytobiosis with Geosiphon pyriforme (Kützing) F. v. Wettstein, were investigated for their photosynthetic competence. Large-scale fractionation of the two stages is presented. Photosynthetic parameters were assessed by measurement of chlorophyll fluorescence and oxygen evolution. Hormogonia were as photosynthetically competent as the colonial stage. In addition, hormogonia showed an enhanced capability for nonradiative dissipation of absorbed light energy, a feature that might be important for their function as propagula. Data for the quantum yield of photosystem II of the isolated Nostoc strain were compared to the values determined in situ in G. pyriforme and indicated the possibility of a higher photosynthetic capacity of the endosymbiotic as compared to the isolated cyanobacterium.  相似文献   
26.
The scientific documentation supporting the potential clinical and economic benefits of a growing use of off-patent generic drugs in clinical practice seems to be limited in Italy as yet.

Methods

We compared differences in outcomes between off-patent generic drugs and off-patent brand drugs in real clinical practice. The outcomes were: persistence and compliance with therapy, mortality, and other health resources consumption (hospitalizations, specialist examinations, other drugs) and total costs. Retrospective analysis was carried out by using the administrative databases of five Local Healthcare Units (ASLs - Aziende Sanitarie Locali) in the Lombardy Region of Italy. Data from the five ASLs were aggregated through a meta-analysis, which produced an estimate indicator of the mean or percentage difference between the two groups (branded vs. generic) and their respective significance tests. The therapeutic areas and studied drugs were: diabetes: metformin - A10BA02; hypertension: amlodipine - C08CA01; dyslipidemia: simvastatin - C10AA01; psychiatry: sertraline - N06AB06; cardiology: propafenone - C01BC03; osteoporosis: alendronate - M05BA04.

Results

The 5 Local Healthcare Units (ASL) represent a population of 3,847,004 inhabitants. The selected sample included 347,073 patients, or 9.02% of the total ASL population; 67% of the patients were treated with off-patent brand drugs. The average age was 68 years, with no difference between the two groups. After 34 months of observation, compliance and persistence were in favor to generic drugs in all therapeutic areas and statistically significant in the metformin, amlodipine, simvastatin, and sertraline groups. The clinical outcomes (hospitalizations, mortality, and other health costs) show no statistically significant differences between off-patent generic vs. off-patent brand medicines.

Conclusions

Off-patent generic drugs appear to be a therapy option of choice in Italy as well, based on clinical outcomes and economic consequences, both for the National Health Service and patients, considering that the price difference between brand and generic drugs is completely charged on patients.  相似文献   
27.
Antifungal type 1 responses are upregulated in IL-10-deficient mice   总被引:4,自引:0,他引:4  
C57BL/6 mice are highly resistant to infections caused by Candida albicans and Aspergillus fumigatus. To elucidate the role of IL-10 produced by C57BL/6 mice during these infections, parameters of infection and immunity to it were evaluated in IL-10-deficient and wild-type mice with disseminated or gastrointestinal candidiasis or invasive pulmonary aspergillosis. Unlike parasitic protozoan infection, C. albicans or A. fumigatus infection did not induce significant acute toxicity in IL-10-deficient mice, who, instead, showed reduced fungal burden and fungal-associated inflammatory responses. The increased resistance to infections as compared to wild-type mice was associated with upregulation of innate and acquired antifungal Th1 responses, such as a dramatically higher production of IL-12, nitric oxide (NO) and TNF-alpha as well as IFN-gamma by CD4+ T cells. Pharmacological inhibition of NO production greatly reduced resistance to gastrointestinal candidiasis, thus pointing to the importance of IL-10-dependent NO regulation at mucosal sites in fungal infections. These results are reminiscent of those obtained in genetically susceptible mice, in which IL-10 administration increased, and IL-10 neutralization decreased, susceptibility to C. albicans and A. fumigatus infections. Collectively, these observations indicate that the absence of IL-10 augments innate and acquired antifungal immunity by upregulating type 1 cytokine responses. The resulting protective Th1 responses lead to a prompt reduction of fungal growth, thus preventing tissue destruction and lethal levels of proinflammatory cytokines.  相似文献   
28.
The ability to tolerate Candida albicans, a human commensal of the gastrointestinal tract and vagina, implicates that host defense mechanisms of resistance and tolerance cooperate to limit fungal burden and inflammation at the different body sites. We evaluated resistance and tolerance to the fungus in experimental and human vulvovaginal candidiasis (VVC) as well as in recurrent VVC (RVVC). Resistance and tolerance mechanisms were both activated in murine VVC, involving IL-22 and IL-10-producing regulatory T cells, respectively, with a major contribution by the enzyme indoleamine 2,3-dioxygenase 1 (IDO1). IDO1 was responsible for the production of tolerogenic kynurenines, such that replacement therapy with kynurenines restored immunoprotection to VVC. In humans, two functional genetic variants in IL22 and IDO1 genes were found to be associated with heightened resistance to RVVC, and they correlated with increased local expression of IL-22, IDO1 and kynurenines. Thus, IL-22 and IDO1 are crucial in balancing resistance with tolerance to Candida, their deficiencies are risk factors for RVVC, and targeting tolerance via therapeutic kynurenines may benefit patients with RVVC.  相似文献   
29.
The presence of the diffuse intimal thickening (DIT) is commonly considered the structural basis for the early atherosclerotic involvement of the coronary arteries. In the ambit of a systematic morphometric comparison of experimental atherosclerotic plaques of aorta and coronaries, we have studied the coronary medio-intimal junctions of 4 months old rabbits. Both at sub-epicardic and intra-myocardic coronary arteries level we have found fiber structures similar to DIT. These findings may help explaining why coronary atherosclerosis in rabbits does not represent, in the usual experimental models, a lesion particularly severe nor of precocious appearance.  相似文献   
30.
The purpose of this pilot study is to asses the effects of multiple pregnancies on the maturation of the developing brain using the polysomnographic EEG recordings. Data from prospectively recorded 10 twin sets, born prematurely (mean 36 gestational week; range 33 - 38 GW) in the Split University Hospital Center, were analysed. We compared sleep architecture parameters in the twins at 37h and 44th postmenstrual age (PMA) with parameters that were expected at that PMA. The same parameters were compared within each twin pair using the Man Whitne test. At first measurement indeterminate sleep (IS) proportion was greater in the first twin than in the second one. The IS sleep proportion was 1.6 fold greater in the first twin (p=0.028), and 1,8 fold less percentage of quite sleep (QS) than the second twin (p=0.054). The length of sleep stages among the twins was similar at the second measurement. Measures of sleep architecture were not significantly different within the twins in second recording. The results of this study obtained on a relatively small number of twins (longer IS and shorter QS in the first twin at the 38th week recordings), showed that the maturational differences among twins exist in utero and shortly after birth, and then disappear until the end of the first month of the postnatal life.  相似文献   
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