A new tool to process forecast meteorological data for atmospheric pollution dispersion simulations of accident scenarios: A Sicily-based case study

Emergency response plans to mitigate the severity of the accidental release of hazardous compounds in the air have become a primary concern in view of the many adverse events occurred over the years in high-risk plants. To do this, an accurate estimate of forecast meteorological data to be used in dispersion models can be very useful to respond in advance to emergency situations. In this field, FORCALM is a new tool developed to elaborate European Centre for Medium-Range Weather Forecasts data on a 3D computational domain with a high-resolution grid. FORCALM data can be used to perform predictive simulations of impacts on local and regional levels by using CALPUFF modelling system. A case study relevant to an accident, occurred in the “Mediterranea” Refinery at Milazzo (Italy) in 2014, has been also examined for validation purposes. A comparison with results obtained by using CALMET modelling system and observed meteorological data, covering the area under study, is also described. The validation work has allowed confirming that predictive assessments, carried out with the help of FORCALM, lead to information regarding potential environmental impacts with a good degree of accuracy

N-acetylcysteine serves as substrate of 3-mercaptopyruvate sulfurtransferase and stimulates sulfide metabolism in colon cancer cells

Hydrogen sulfide (H2S) is an endogenously produced signaling molecule. The enzymes 3-mercaptopyruvate sulfurtransferase (MST), partly localized in mitochondria, and the inner mitochondrial membrane-associated sulfide:quinone oxidoreductase (SQR), besides being respectively involved in the synthesis and catabolism of H2S, generate sulfane sulfur species such as persulfides and polysulfides, currently recognized as mediating some of the H2S biological effects. Reprogramming of H2S metabolism was reported to support cellular proliferation and energy metabolism in cancer cells. As oxidative stress is a cancer hallmark and N-acetylcysteine (NAC) was recently suggested to act as an antioxidant by increasing intracellular levels of sulfane sulfur species, here we evaluated the effect of prolonged exposure to NAC on the H2S metabolism of SW480 colon cancer cells. Cells exposed to NAC for 24 h displayed increased expression and activity of MST and SQR. Furthermore, NAC was shown to: (i) persist at detectable levels inside the cells exposed to the drug for up to 24 h and (ii) sustain H2S synthesis by human MST more effectively than cysteine, as shown working on the isolated recombinant enzyme. We conclude that prolonged exposure of colon cancer cells to NAC stimulates H2S metabolism and that NAC can serve as a substrate for human MST

The representation of immigrants muslim women in the italian mass media

Este trabajo analiza, desde una perspectiva de género, las representaciones que transmite la prensa italiana sobre las mujeres migrantes musulmanas. Una imagen que condiciona la manera en que la sociedad percibe a este grupo de población. Para ello se propone un análisis cualitativo de las noticias de tres periódicos italianos de tirada nacional: La Repubblica, Il Resto del Carlino, Corriere della Sera. Indagamos en el tipo de representaciones discursivas (temáticas e imágenes) que se hace sobre estas mujeres desde 2001 a 2018, así como en los contextos de producción (autoría, encuadre y temporalidad) de las noticias en las que aparecen. El análisis de la información nos muestra como la imagen de las mujeres migrantes musulmanas sigue construyéndose desde una mirada cosificada, patriarcal y etnocéntrica, asociada a estereotipos justificados en las ideas de sospecha, sumisión y opresión

Glucose Metabolism in the Progression of Prostate Cancer

Prostate cancer is one of the most common types of cancer in western country males but the mechanisms involved in the transformation processes have not been clearly elucidated. Alteration in cellular metabolism in cancer cells is recognized as a hallmark of malignant transformation, although it is becoming clear that the biological features of metabolic reprogramming not only differ in different cancers, but also among different cells in a type of cancer. Normal prostate epithelial cells have a peculiar and very inefficient energy metabolism as they use glucose to synthesize citrate that is secreted as part of the seminal liquid. During the transformation process, prostate cancer cells modify their energy metabolism from inefficient to highly efficient, often taking advantage of the interaction with other cell types in the tumor microenvironment that are corrupted to produce and secrete metabolic intermediates used by cancer cells in catabolic and anabolic processes. We recapitulate the metabolic transformations occurring in the prostate from the normal cell to the metastasis, highlighting the role of the microenvironment and summarizing what is known on the molecular mechanisms involved in the process

A pyrazolopyran derivative preferentially inhibits the activity of human cytosolic hydroxymethyltransferase and induces cell death in lung cancer cells

Serine hydroxymethyltransferase (SHMT) is a central enzyme in the metabolic reprogramming of cancer cells, providing activated one-carbon units in the serine-glycine one-carbon metabolism. Previous studies demonstrated that the cytoplasmic isoform of SHMT (SHMT1) plays a relevant role in lung cancer. SHMT1 is overexpressed in lung cancer patients and NSCLC cell lines. Moreover, SHMT1 is required to maintain DNA integrity. Depletion in lung cancer cell lines causes cell cycle arrest and uracil accumulation and ultimately leads to apoptosis. We found that a pyrazolopyran compound, namely 2.12, preferentially inhibits SHMT1 compared to the mitochondrial counterpart SHMT2. Computational and crystallographic approaches suggest binding at the active site of SHMT1 and a competitive inhibition mechanism. A radio isotopic activity assay shows that inhibition of SHMT by 2.12 also occurs in living cells. Moreover, administration of 2.12 in A549 and H1299 lung cancer cell lines causes apoptosis at LD50 34 μM and rescue experiments underlined selectivity towards SHMT1. These data not only further highlight the relevance of the cytoplasmic isoform SHMT1 in lung cancer but, more importantly, demonstrate that, at least in vitro, it is possible to find selective inhibitors against one specific isoform of SHMT, a key target in metabolic reprogramming of many cancer types

An Immunological Analysis of Dystroglycan Subunits: Lessons Learned from a Small Cohort of Non-Congenital Dystrophic Patients

The dystroglycan (DG) expression pattern can be altered in severe muscular dystrophies. In fact, some congenital muscular dystrophies (CMDs) and limb-girdle muscular dystrophies (LGMDs) are caused by point mutations identified in six glycosyltransferase genes which are likely to target different steps along the posttranslational “O-glycosylation route” leading to a fully decorated and functional α-DG subunit. Indeed, hypoglycosylation of α-DG is thought to represent a major pathological event, in that it could reduce the DG’s ability to bind the basement membrane components, thus leading to sarcolemmal instability and necrosis. In order to set up an efficient standard immunological protocol, taking advantage of a wide panel of antibodies, we have analyzed the two DG subunits in a small cohort of adult dystrophic patients, whom an extensive medical examination had already clinically classified as affected by LGMD (5), Miyoshi (1) or distal (1) myopathy. Immunofluorescence analysis of skeletal muscle tissue sections revealed a proper sarcolemmal localization of the DG subunits in all the patients analyzed. However, Western blot analysis of lectin enriched skeletal muscle samples revealed an abnormal glycosylation of α-DG in two patients. Our work reinforces the notion that a careful immunological and biochemical analysis of the two DG subunits should be always considered as a prerequisite for the identification of new putative cases of dystroglycanopathy

N-Acetylcysteine Serves as Substrate of 3-Mercaptopyruvate Sulfurtransferase and Stimulates Sulfide Metabolism in Colon Cancer Cells

Hydrogen sulfide (H2S) is an endogenously produced signaling molecule. The enzymes 3-mercaptopyruvate sulfurtransferase (MST), partly localized in mitochondria, and the inner mitochondrial membrane-associated sulfide:quinone oxidoreductase (SQR), besides being respectively involved in the synthesis and catabolism of H2S, generate sulfane sulfur species such as persulfides and polysulfides, currently recognized as mediating some of the H2S biological effects. Reprogramming of H2S metabolism was reported to support cellular proliferation and energy metabolism in cancer cells. As oxidative stress is a cancer hallmark and N-acetylcysteine (NAC) was recently suggested to act as an antioxidant by increasing intracellular levels of sulfane sulfur species, here we evaluated the effect of prolonged exposure to NAC on the H2S metabolism of SW480 colon cancer cells. Cells exposed to NAC for 24 h displayed increased expression and activity of MST and SQR. Furthermore, NAC was shown to: (i) persist at detectable levels inside the cells exposed to the drug for up to 24 h and (ii) sustain H2S synthesis by human MST more effectively than cysteine, as shown working on the isolated recombinant enzyme. We conclude that prolonged exposure of colon cancer cells to NAC stimulates H2S metabolism and that NAC can serve as a substrate for human MST

Studying GGDEF Domain in the Act: Minimize Conformational Frustration to Prevent Artefacts

GGDEF-containing proteins respond to different environmental cues to finely modulate cyclic diguanylate (c-di-GMP) levels in time and space, making the allosteric control a distinctive trait of the corresponding proteins. The diguanylate cyclase mechanism is emblematic of this control: two GGDEF domains, each binding one GTP molecule, must dimerize to enter catalysis and yield c-di-GMP. The need for dimerization makes the GGDEF domain an ideal conformational switch in multidomain proteins. A re-evaluation of the kinetic profile of previously characterized GGDEF domains indicated that they are also able to convert GTP to GMP: this unexpected reactivity occurs when conformational issues hamper the cyclase activity. These results create new questions regarding the characterization and engineering of these proteins for in solution or structural studies

Mutational analysis of Peroxiredoxin IV: exclusion of a positional candidate for multinodular goitre

BACKGROUND: Multinodular goitre (MNG) is a common disorder characterised by an enlargement of the thyroid, occurring as a compensatory response to hormonogenesis impairment. The incidence of MNG is dependent on sex (female:male ratio 5:1) and several reports have documented a genetic basis for the disease. Last year we mapped a MNG locus to chromosome Xp22 in a region containing the peroxiredoxin IV (Prx-IV) gene. Since Prx-IV is involved in the removal of H(2)O(2) in thyroid cells, we hypothesize that mutations in Prx-IV gene are involved in pathogenesis of MNG. METHODS: Four individuals (2 affected, 2 unrelated unaffected) were sequenced using automated methods. All individuals were originated from the original three-generation Italian family described in previous studies. A Southern blot analysis using a Prx-IV full-length cDNA as a probe was performed in order to exclude genomic rearrangements and/or intronic mutations. In addition a RT-PCR of PRX-IV was performed in order to investigate expression alterations. RESULTS: No causative mutations were found. Two adjacent nucleotide substitutions were detected within introns 1 and 4. These changes were also detected in unaffected individuals, suggesting that they were innocuous polymorphisms. No gross genomic rearrangements and/or restriction fragment alterations were observed on Southern analysis. Finally, using RT-PCR from tissue-specific RNA, no differences of PRX-IV expression-levels were detected between affected and unaffected samples. CONCLUSIONS: Based on sequence and genomic analysis, Prx-IV is very unlikely to be the MNG2 gene

Radiation damage at the active site of human alanine:glyoxylate aminotransferase reveals that the cofactor position is finely tuned during catalysis

The alanine:glyoxylate aminotransferase (AGT), a hepatocyte-specific pyridoxal-5'-phosphate (PLP) dependent enzyme, transaminates L-alanine and glyoxylate to glycine and pyruvate, thus detoxifying glyoxylate and preventing pathological oxalate precipitation in tissues. In the widely accepted catalytic mechanism of the aminotransferase family, the lysine binding to PLP acts as a catalyst in the stepwise 1,3-proton transfer, interconverting the external aldimine to ketimine. This step requires protonation by a conserved aspartate of the pyridine nitrogen of PLP to enhance its ability to stabilize the carbanionic intermediate. The aspartate residue is also responsible for a significant geometrical distortion of the internal aldimine, crucial for catalysis. We present the structure of human AGT in which complete X-ray photoreduction of the Schiff base has occurred. This result, together with two crystal structures of the conserved aspartate pathogenic variant (D183N) and the molecular modeling of the transaldimination step, led us to propose that an interplay of opposite forces, which we named spring mechanism, finely tunes PLP geometry during catalysis and is essential to move the external aldimine in the correct position in order for the 1,3-proton transfer to occur