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Microbial enzyme activities on organic polymers were tested as possible sentinels of anthropic and natural forcings during a two-year study in two coastal Antarctic areas (Road Bay and Tethys Bay respectively). In Road Bay high proteolytic activity rates were measured at a site impacted by the Italian research station sewage, due to faecal wastes; in Tethys Bay low salinity waters related to glacier presence were characterized by high enzyme activities probably associated to detritus from ice melting.

Recent studies have assessed that microbial parameters may be used as bioindicators of climate change in the carbon cycle. The carbon fl ux in aquatic environments is ruled by microorganisms that provide both organication and oxidation of the organic matter by means of production and respiration, respectively. Recent studies on the global carbon budget show that not always a coupling between microbial autotrophic and heterotrophic activities exists. Consequently, aquatic environments can act as sink or source of CO2 in relation to productive or degradative processes, respectively. Our working group for more than a decade studying the role of microbial activity in the biogeochimical processes in the deep Mediterranean Sea and in the Antarctic Ocean which are interesting for several search sites. Recently, transitional areas are often studied for resource management and exploitation. Brackish ecosystems are among the most geochemically and biologically active areas of the biosphere and it plays a considerable role in the global biogeochemichal cycle. Some studies have shown that, in lakes with different trophic state, measurements of microbial activities over the organic matter provide ecological information in terms of functional effi ciency of the microbial community that could be useful for resource management. Microorganisms affect signifi cantly the lake biogeochemistry . In fact, owing to their high abundance, biochemical diversity and quick turnover times, they promptly responds to environmental changes and utilize a wide spectrum of nutritional sources. In transitional environments, microbial autotrophic and heterotrophic activities may be balanced or unbalanced in relation to the ecosystem maturity. Consequently, microorganisms can act as sink or source of CO2 in relation to their dominant metabolism, respectively. Nothwithstanding their peculiarities and biodiversity, up to date few research considered microbial community and biogeochemical processes in lagoons that sometimes result characterized by marked diversifi cation of the trophic levels, organic matter turnover and metabolic C budget both at spatial and seasonal scales, with conditions ranging from oligotrophy to eutrophy. The occurrence of seasonal trophic imbalances in these oligotrophic ecosystems confi rm their vulnerability to climate changes.

Carbon dioxide production rates (CDPR) of micro-organisms were monitored through their electron transport system (ETS) activity in thedeep Ross Sea. The depth-integrated CDPR amounted to 28,2 mg C m-2d-1in the depth range 100-1000 m. Comparing CDPR determinedin this study with that obtained by sediment traps in the Ross Sea resulted that about 63% of organic carbon remineralized by respirationderived from POC pool. Such evidence highlighted POC source as main organic fuel of biological pump in the Ross Sea.

Microplankton respiration in the euphotic zone in the Central Mediterranean Sea was calculated by ETS activity measurements. Distribution of ETSa in the studied area appeared homogeneous and comparable with previous data measured in the Mediterranean Sea. A typical ETSa value for euphotic Mediterranean waters of 0.14 meq O2 h-1 m-3 was calculated. The investigated area supports a metabolic CO2 production of 70 g C m-2 y-1. When compared with regional productivity, the respiration budget in the euphotic zone accounted for 22% of carbon fixed. ETSa appeared a useful assay for the study of evolutive history of the water masses in the Mediterranean Sea.

Respiratory rates in two areas of the North Adriatic Sea were studied in the context of a PRISMA II Project, with the aim of quantifying the oxidative processes occurring in the frontal system caused by strong riverine discharge. In the northern area, higher respiratory rates and seasonal variations occurred with respect to the southern area. On average, respiratory activity sustained the oxidation of 66.9 nM C h(-1) inside the front and 24.4 nM C h(-1) outside the front. In conclusion, organic matter oxidation inside the front resulted 2.7 times higher than outside the front. Oxidative metabolism in the Northern Adriatic Sea appears mainly governed by river inputs.

Inborn errors of metabolism (IEM) are disorders affecting human biochemical pathways and represent attractive targets for gene therapy because of their severity, high overall prevalence, lack of effective treatments, and possibility of early diagnosis through newborn screening. The liver is a central organ involved in several metabolic reactions and is a favorite target for gene therapy in many IEM. Adeno-associated virus (AAV) vectors have emerged in the last years as the preferred vectors for in vivo gene delivery. Gene replacement strategies are aimed either at correcting liver disease or providing a source for production and secretion of the lacking enzyme for cross-correction of other tissues. A number of preclinical studies have been conducted in the last years and, for several diseases, gene therapy has reached the clinical stage, with a growing number of ongoing clinical trials. Moreover, recent applications of genome editing to the field of inherited metabolic diseases have further expanded potential therapeutic possibilities. This review describes relevant clinical gene therapy studies for IEM with particular attention to current obstacles and drawbacks.

Enzyme replacement therapy (ERT) has become the standard of care for several lysosomal storage disorders (LSDs). Despite ERT's undisputed efficacy, the requirement for multiple and costly administrations as well as ERT's limited improvement of some LSD manifestations prompts the search for better therapies. Using a mouse model of mucopolysaccharidosis VI, we compared the efficacy of a single intravascular administration of an adeno-associated viral vector targeting liver to weekly infusions of human recombinant enzyme at the same doses used in mucopolysaccharidosis VI patients. While gene therapy results in increased and stable levels of circulating enzyme up to 1 year after vector administration, ERT has typical peak-and-drop serum kinetics. Both therapies similarly reduced glycosaminoglycan levels in urine and tissues including heart valves and myocardium, with gene therapy improving skeletal skull abnormalities slightly better, although not significantly, than ERT. Both therapies seem to similarly improve animal motor performance, with gene therapy possibly associated with less animal distress. Thus, a single vector administration that converts liver into a factory organ for systemic secretion of therapeutic proteins is at least as effective as ERT in a mouse model of LSD, potentially eliminating problems with compliance and costs. Only testing in humans will prove whether this holds true in a clinical setting.

MicroRNAs (miRNAs) are small non-coding RNAs that regulate the expression of different genes, including genes involved in cancer progression. A functional link between hypoxia, a key feature of the tumor microenvironment, and miRNA expression has been documented. We investigated whether and how miR-20b can regulate the expression of vascular endothelial growth factor (VEGF) in MCF-7 breast cancer cells under normoxic and hypoxia-mimicking conditions (CoCl(2) exposure). Using immunoblotting, ELISA, and quantitative real-time PCR, we demonstrated that miR-20b decreased VEGF protein levels at 4 and 24 h following CoCl(2) treatment, and VEGF mRNA at 4 h of treatment. In addition, miR-20b reduced VEGF protein expression in untreated cells. Next, we investigated the molecular mechanism by which pre-miR-20b can affect VEGF transcription, focusing on hypoxia inducible factor 1 (HIF-1) and signal transducer and activator of transcription 3 (STAT3), transcriptional inducers of VEGF and putative targets of miR-20b. Downregulation of VEGF mRNA by miR-20b under a 4 h of CoCl(2) treatment was associated with reduced levels of nuclear HIF-1 alpha subunit and STAT3. Chromatin immunoprecipitation (ChIP) assays revealed that HIF-1 alpha, but not STAT3, was recruited to the VEGF promoter following the 4 h of CoCl(2) treatment. This effect was inhibited by transfection of cells with pre-miR-20b. In addition, using siRNA knockdown, we demonstrated that the presence of STAT3 is necessary for CoCl(2)-mediated HIF-1 alpha nuclear accumulation and recruitment on VEGF promoter. In summary, this report demonstrates, for the first time, that the VEGF expression in breast cancer cells is mediated by HIF-1 and STAT3 in a miR-20b-dependent manner.