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21.
The European Water Framework Directive (WFD) (2000/60/EC) requires assessing the ecological quality status of water bodies, and gives great importance to the biological components of the ecosystem. Within this framework, a multimetric, fuzzy-based index for the evaluation of environmental quality (FINE: fuzzy index of ecosystem integrity) has been developed using data from several Italian coastal lagoons, gathered with seasonal frequency at diverse sites in each lagoon. The rationale of FINE is that certain attributes, selected on the basis of established principles of benthic ecology, are fundamental for lagoon ecosystem function. FINE is composed of seven ecosystem attributes (variables) each of which have ecological relevance for lagoon ecosystems. Individually, all these attributes are themselves useful indices of environmental conditions. However, the combination of these attributes into a single fuzzy index, provides a more robust, overall index of the response of the natural communities to environmental perturbations and avoids misleading or ambiguous results. Each variable is not represented by a single numerical value, but by several categories that describe its properties: in the present model we considered a total of seven variables: two with four modalities (low–medium–high–very high), one with three (low–medium–high) and three with two (low–high), plus a qualitative variable (yes–no), that altogether generate 768 rules. FINE is a low-cost, flexible and robust routine index of lagoon ecosystem impairment and could be of particular benefit to environmental managers and policymakers who require tools capable of expressing the degree of degradation or environmental quality of different lagoon habitats. For its relative simplicity in the application, FINE could be a good candidate to assess the environmental quality of Mediterranean transitional ecosystems. Guest editors: A. Razinkovas, Z. R. Gasiūnaitė, J. M. Zaldivar & P. Viaroli European Lagoons and their Watersheds: Function and Biodiversity  相似文献   
22.

Background

Diesel exhaust particles (DEPs) are deposited into the respiratory tract and are thought to be a risk factor for the development of diseases of the respiratory system. In healthy individuals, the timing and mechanisms of respiratory tract injuries caused by chronic exposure to air pollution remain to be clarified.

Methods

We evaluated the effects of chronic exposure to DEP at doses below those found in a typical bus corridor in Sao Paulo (150 μg/m3). Male BALB/c mice were divided into mice receiving a nasal instillation: saline (saline; n = 30) and 30 μg/10 μL of DEP (DEP; n = 30). Nasal instillations were performed five days a week, over a period of 90 days. Bronchoalveolar lavage (BAL) was performed, and the concentrations of interleukin (IL)-4, IL-10, IL-13 and interferon-gamma (INF-γ) were determined by ELISA-immunoassay. Assessment of respiratory mechanics was performed. The gene expression of Muc5ac in lung was evaluated by RT-PCR. The presence of IL-13, MAC2+ macrophages, CD3+, CD4+, CD8+ T cells and CD20+ B cells in tissues was analysed by immunohistochemistry. Bronchial thickness and the collagen/elastic fibers density were evaluated by morphometry. We measured the mean linear intercept (Lm), a measure of alveolar distension, and the mean airspace diameter (D0) and statistical distribution (D2).

Results

DEP decreased IFN-γ levels in BAL (p = 0.03), but did not significantly alter IL-4, IL-10 and IL-13 levels. MAC2+ macrophage, CD4+ T cell and CD20+ B cell numbers were not altered; however, numbers of CD3+ T cells (p ≤ 0.001) and CD8+ T cells (p ≤ 0.001) increased in the parenchyma. Although IL-13 (p = 0.008) expression decreased in the bronchiolar epithelium, Muc5ac gene expression was not altered in the lung of DEP-exposed animals. Although respiratory mechanics, elastic and collagen density were not modified, the mean linear intercept (Lm) was increased in the DEP-exposed animals (p ≤ 0.001), and the index D2 was statistically different (p = 0.038) from the control animals.

Conclusion

Our data suggest that nasal instillation of low doses of DEP over a period of 90 days results in alveolar enlargement in the pulmonary parenchyma of healthy mice.

Electronic supplementary material

The online version of this article (doi:10.1186/s12931-015-0172-z) contains supplementary material, which is available to authorized users.  相似文献   
23.

Background  

This study aimed to analyze the efficiency of three new microsatellite multiplex panels, which were designed to evaluate a total of 16 loci of the rice genome, based on single PCR reactions of each panel. A sample of 548 accessions of traditional upland rice landraces collected in Brazil in the last 25 years was genotyped, a database of allelic frequencies was established, estimates of genetic parameters were performed and analysis of genetic structure of the collection was developed.  相似文献   
24.

Background  

In normal adult skeletal muscle, cell turnover is very slow. However, after an acute lesion or in chronic pathological conditions, such as primary myopathies, muscle stem cells, called satellite cells, are induced to proliferate, then withdraw definitively from the cell cycle and fuse to reconstitute functional myofibers.  相似文献   
25.

Background

Memory responses require immune competence. We assessed the influence of priming with AS03-adjuvanted pandemic vaccine (Pandemrix®) on memory responses of HIV patients, kidney recipients (SOT) and healthy controls (HC).

Method

Participants (HIV: 197, SOT: 53; HC: 156) were enrolled in a prospective study and 390/406 (96%) completed it. All had been primed in 2009/2010 with 1 (HC) or 2 (patients) doses of Pandemrix®, and were boosted with the 2010/2011 seasonal influenza vaccine. Geometric mean titres and seroprotection rates were measured 12 months after priming and 4 weeks after boosting. Primary and memory responses were directly compared in 191 participants (HCW: 69, HIV: 71, SOT: 51) followed during 2 consecutive seasons.

Results

Most participants (HC: 77.8%, HIV: 77.6%, SOT: 66%) remained seroprotected at 12 months post-priming. Persisting A/09/H1N1 titers were high in HIV (100.2) and HC (120.1), but lower in SOT (61.4) patients. Memory responses reached higher titers in HIV (507.8) than in HC (253.5) and SOT (136.9) patients. Increasing age and lack of HAART reduced persisting and memory responses, mainly influenced by residual antibody titers. Comparing 2009/2010 and 2010/2011 titers in 191 participants followed for 2 seasons indicated lower post-2010/2011 titers in HC (240.2 vs 313.9), but higher titers in HIV (435.7 vs 338.0) and SOT (136 vs 90.3) patients.

Conclusions

Priming with 2 doses of Pandemrix® elicited persistent antibody responses and even stronger memory responses to non-adjuvanted seasonal vaccine in HIV patients than 1 dose in healthy subjects. Adjuvanted influenza vaccines may improve memory responses of immunocompromised patients.

Trial Registration

ClinicalTrials.gov NCT01022905  相似文献   
26.
27.
As a tool to better understand the organization of the olfactory pathway three monoclonal antibodies have been isolated and characterized each having a unique staining pattern in the antenna and antennal lobe of Drosophila melanogaster. Monoclonal antibody F14-2D6 stains sensilla coeloconica and thick sensilla basiconica in the funiculus, Y1-3D10 stains only a few sensilla especially in and around the sacculus, while F15-12E8 stains all the sensilla. All three antibodies stain a subset of the glomeruli in the antennal lobe, of which 11 glomeruli are stained in common by all three antibodies. These antibodies could be used to study projection patterns of the sensilla into the antennal lobe. Glomerular staining was observed at different developmental times with the different antibodies. F15-12E8 stains all the glomeruli at eclosion, Y1-3D10 stains only a few glomeruli at eclosion but most glomeruli are stained by the first day after eclosion. F14-2D6 stains all glomeruli only after eclosion. F15-12E8 also stains the mushroom bodies. The antigen recognized by F14-2D6 in the glomeruli shows an increase with age of the flies, measured as increased intensity of staining. These observations suggest that age-related changes continue in the antennal lobe of the flies even after eclosion. These antibodies could therefore serve as unique markers for other studies on the development of the olfactory system.  相似文献   
28.

Background  

Breeding programs are usually reluctant to evaluate and use germplasm accessions other than the elite materials belonging to their advanced populations. The concept of core collections has been proposed to facilitate the access of potential users to samples of small sizes, representative of the genetic variability contained within the gene pool of a specific crop. The eventual large size of a core collection perpetuates the problem it was originally proposed to solve. The present study suggests that, in addition to the classic core collection concept, thematic core collections should be also developed for a specific crop, composed of a limited number of accessions, with a manageable size.  相似文献   
29.
The X-linked color pigment (opsin) locus is known to be highly polymorphic in the squirrel monkey and other New World monkeys. To see whether this is also the case for the autosomal (blue) opsin locus, we obtained 32 squirrel monkey and 30 human blue opsin gene sequences. No amino acid polymorphism was found in either the squirrel monkey sample or the human sample, contrary to the situation at the X-linked opsin locus. This sharp contrast in the level of polymorphism might be due to differences in gene expression between the autosomal and the X-linked loci. At the X-linked locus, heterozygote advantage can occur because, owing to X-inactivation, the two alleles in a heterozygote are expressed in different cone cells, producing two types of cone cell, whereas at the autosomal locus, heterozygote advantage cannot occur because the two alleles in a heterozygote are expressed in the same cone cells, producing only one type of cone cell (i.e., phenotypically a homozygote). From the sequence data, the levels of nucleotide diversity (pi, i.e., the number of nucleotide differences per site) are estimated: for the human sample, pi = 0.00% per nondegenerate site, 0.00% per twofold degenerate site, and 0.04% per fourfold degenerate site in the coding regions and 0.01% per site in intron 4; for the squirrel monkey sample, pi = 0.00% per nondegenerate site, 0.00% per twofold degenerate site, and 0.15% per fourfold degenerate site in the coding regions and 0.17% per site in intron 4. The blue opsin genes from the common and pygmy chimpanzees, the gorilla, the capuchin, and the howler monkey were also sequenced. Features critical to the function of the opsin are well conserved in all known mammalian sequences. However, the interhelical loops are, on average, actually more conservative than the transmembrane helical regions. In addition, these sequence data and those from some other genes indicate that the common and pygmy chimpanzees are not closely related, their divergence data being from one third to one half the date of the human-chimpanzee divergence.   相似文献   
30.
A functional immunoassay, that has proved very useful, is described for screening and identifying monoclonal antibodies (McAbs) against scarce and labile enzymes. This method does not require purified enzyme or antigen and it has been successfully applied to isolate three hybridomas secreting McAbs to NADPH:nitrate reductase from the chloronema cells of the mossFunaria hygrometrica. Briefly, the protocol involves: adsorption of murine antibodies from hybridoma supernatants by rabbit antimouse IgG antibody pre-adsorbed toStaphylococcus aureus cells (SAC), reaction with crude extract for 15 min, sedimentation of the SAC complex by centrifugation and measurement of residual enzymatic activity in the supernatant. A depletion indicates the presence of antibodies that bind to the active enzyme. The method is rapid, sensitive and versatile enough to be used to isolate McAbs with exquisite specificities. The three isolated McAbs recognized nitrate reductase protein in a conformation-independent and/or a conformation-dependent manner.  相似文献   
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