Heterogeneity in renal structure has been described in t y p e 2 diabetic patients with both microalbuminuria and proteinuria; in fact, only a subset of type 2 diabetic patients have the typical diabetic glomerulopathy. Howe v e r, it is currently unknown whether abnormalities in albumin excretion rate (AER) have a different renal prognostic value depending on the underlying renal structure. Aims of this study were: 1) to study the course of renal function in type 2 diabetic patients with altered AER; 2) to evaluate the relationship between the course of glomerular filtration rate (GFR) and renal structure; and 3) to evaluate the relationship between the course of GFR and baseline AER levels, metabolic control, and blood pressure levels during a follow-up period of 4 years. A total of 108 type 2 diabetic patients, 74 with microalbuminuria (MA) and 34 with proteinuria (P), were recruited into a prospective study that encompassed: 1) a baseline kidney biopsy with morphometric measurements of glomerular parameters; 2) intensified antihypertensive treatment for an average 4-year period (blood pressure target < 1 4 0 / 9 0 mmHg); and 3) determinations of GFR at baseline and every 6 months. Mean (± SD) GFR significantly decreased from baseline in both MA (-1.3 ± 9.4 [95% CI -3.51 to +0.86], P < 0.05) and P (-3.0 ± 13.0 m l · min -1 · 1.73 m -2 per year [-7.71 to +1.61], P < 0.01). However, the changes in GFR were quite heterogeneous. Thus, on the basis of percent GFR change per year from baseline ( %GFR), both MA and P patients were defined as progressors or nonprogressors when they were below or above the median, respectively. Baseline parameters of glomerular structure had a strong influence on the course of GFR. Indeed, the odds ratios of being progressors significantly increased across the quartiles of baseline glomerular basement membrane (GBM) width and mesangial fractional volume [Vv(mes/glom)], being 2.71 and 2.85 higher, respectively, in the fourth quartile than in the first quartile (P < 0.01 for both). Conv e r s e l y, nonprogressors outnumbered progressors in the first quartile of GBM width (odds ratio: 2.14, P < 0.05) and in the first quartile of Vv(mes/glom) (odds ratio: 2.28, P < 0.01). Baseline albumin excretion rate (AER) did not influence %GFR; in fact, the number of progressors did not increase across quartiles of baseline AER among either MA or P. Similarly, mean blood pressure levels during follow-up (and intensified antihypertensive therapy) did not affect the course of GFR: the number of progressors and nonprogressors did not change across quartiles of mean blood pressure. In contrast, HbA 1 c during follow-up had an impact on % G F R : the odds ratio for being a progressor increased across quartiles of HbA 1 c , particularly for the highest quartile ( H b A 1 c >9.0%). In conclusion, the course of renal function is heterogeneous in type 2 diabetic patients with microalbuminuria or proteinuria. In fact, a subset of patients has a rapid decline in GFR over a 4-year followup period; these patient...
The determination of the trophic status of transitional ecosystems from the physico-chemical and biological point of view is one of the requirements of the European Water Framework Directive (WFD 2000/60/EC). In Italy, its determination is implemented by the Regional Agencies for Environmental Protection (ARPAs) that have activated multi-annual monitoring programs. However, as the availability of funds is increasingly scarce, the number of environmental parameters to detect environmental changes should be conveniently managed. The high number of environmental parameters, nutrient and macrophyte datasets available for the LTER-Italia site “Venice lagoon” can be an useful tool to analyze the trophic changes over recent years and to foresee environmental evolutions. Nutrient data on a spatial basis have been available since 1948, whereas macroalgal maps date back to 1980. The aim of this paper is to highlight the changes of the trophic status of the lagoon since the middle of the 20th century by considering the concentrations of nutrients in the surface sediments and in the water column, the variation of some physico-chemical parameters and the biomass of macroalgae and also to foresee the way it will possibly evolve. In fact, after many anthropogenic impacts that in the second half of the 20th century affected the lagoon, starting from the year 2010, the ecological status is progressively improving. Nutrients show a significant reduction both in the water column and in surface sediments, and the macrophytes are represented by species of higher ecological value while the opportunistic species such as the Ulvaceae are in strong regression.
One of the main challenges to facilitate the classification of water bodies is to identify direct relationships between anthropogenic pressures and the behavior of biological organisms such as macrophytes in different environments including transitional areas. The investigation of many lagoons and ponds described here shows that macrophyte variables and the community composition have strong and univocal relationships with ecological parameters that are a measure of anthropogenic pressure on the ecological status of water bodies. The areas surveyed represent about 78% of the Italian transitional waters (169 sites sampled both in spring and fall). Anthropogenic impacts affect the availability of nutrients in the water column and surface sediments, causing changes in water transparency and phytoplankton concentration (as chlorophyll-a [Chl-a]) that act as the main drivers of variation for macrophyte assemblages, changing species dominance and the conditions that govern their presence or absence. The response of macrophytes to anthropogenic pressure is quite similar in all the examined transitional environments, even when the basin morphology, species richness and composition are different. Some taxa and species assemblages are so sensitive to environmental changes that monitoring them can be considered the most suitable and rapid method for assessing the quality of the environment they inhabit
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