36 research outputs found

    Metabolism of hexachlorobenzene in humans: association between serum levels and urinary metabolites in a highly exposed population.

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    Serum and urine from 100 subjects of a general population highly exposed to airborne hexachlorobenzene (HCB) were analyzed to obtain new insights into the metabolism of this ubiquitous compound. HCB was detected in all serum samples with concentrations ranging between 1.1 and 953 ng/ml. The major known metabolites of HCB were investigated in urine collected over 24 hr. Pentachlorophenol (PCP) was detected in all urines with values ranging between 0.58 and 13.9 micrograms excreted in 24 hr [mean +/- standard deviation (SD), 2.52 +/- 2.05; geometric mean, 2.05]. A sulfur derivative that, after hydrolysis, yielded pentachlorobenzenethiol (PCBT) could also be identified and quantified in all the urines with values ranging between 0.18 and 84.0 micrograms of PCBT excreted in 24 hr (mean +/- SD, 3.47 +/- 10.8; geometric mean, 1.39). The sulfur derivative assessed as PCBT appeared to be the main metabolite, with urinary concentrations surpassing those of PCP in the subjects with higher HCB accumulation (HCB in serum > 32 ng/ml). PCBT concentration in urine collected over 24 hr showed a very strong association with HCB concentration in serum; the association was stronger in males than in females. An increase of 1 ng/ml of HCB in serum led to an increase of 2.12 micrograms of PCBT excreted in urine collected over 24 hr in males (95% CI, 1.82-2.44) and to an increase of 0.67 microgram of PCBT in females (CI, 0.33-1.09). A weaker association was found between PCP in urine and HCB in serum, which was only statistically significant in males (an increase of 1 ng/ml of HCB in serum led to an increase of 0.63 microgram of PCP excreted in urine collected over 24 hr; (CI, 0.34-0.95). These results show that the formation of the cysteine conjugate is a quantitatively more important metabolic pathway in humans than the formation of PCP. Moreover, the association found suggests that PCBT is a good urinary marker of HCB internal dose and glutathione-mediated metabolism

    Transgenic Expression of Soluble Human CD5 Enhances Experimentally-Induced Autoimmune and Anti-Tumoral Immune Responses

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    CD5 is a lymphoid-specific transmembrane glycoprotein constitutively expressed on thymocytes and mature T and B1a lymphocytes. Current data support the view that CD5 is a negative regulator of antigen-specific receptor-mediated signaling in these cells, and that this would likely be achieved through interaction with CD5 ligand/s (CD5L) of still undefined nature expressed on immune or accessory cells. To determine the functional consequence of loss of CD5/CD5L interaction in vivo, a new transgenic mouse line was generated (shCD5EμTg), expressing a circulating soluble form of human CD5 (shCD5) as a decoy to impair membrane-bound CD5 function. These shCD5EμTg mice showed an enhanced response to autologous antigens, as deduced from the presentation of more severe forms of experimentally inducible autoimmune disease (collagen-induced arthritis, CIA; and experimental autoimmune encephalitis, EAE), as well as an increased anti-tumoral response in non-orthotopic cancer models (B16 melanoma). This enhancement of the immune response was in agreement with the finding of significantly reduced proportions of spleen and lymph node Treg cells (CD4+CD25+FoxP3+), and of peritoneal IL-10-producing and CD5+ B cells, as well as an increased proportion of spleen NKT cells in shCD5EμTg mice. Similar changes in lymphocyte subpopulations were observed in wild-type mice following repeated administration of exogenous recombinant shCD5 protein. These data reveal the relevant role played by CD5/CD5L interactions on the homeostasis of some functionally relevant lymphocyte subpopulations and the modulation of immune responses to autologous antigens

    Trends and outcome of neoadjuvant treatment for rectal cancer: A retrospective analysis and critical assessment of a 10-year prospective national registry on behalf of the Spanish Rectal Cancer Project

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    Introduction: Preoperative treatment and adequate surgery increase local control in rectal cancer. However, modalities and indications for neoadjuvant treatment may be controversial. Aim of this study was to assess the trends of preoperative treatment and outcomes in patients with rectal cancer included in the Rectal Cancer Registry of the Spanish Associations of Surgeons. Method: This is a STROBE-compliant retrospective analysis of a prospective database. All patients operated on with curative intention included in the Rectal Cancer Registry were included. Analyses were performed to compare the use of neoadjuvant/adjuvant treatment in three timeframes: I)2006–2009; II)2010–2013; III)2014–2017. Survival analyses were run for 3-year survival in timeframes I-II. Results: Out of 14, 391 patients, 8871 (61.6%) received neoadjuvant treatment. Long-course chemo/radiotherapy was the most used approach (79.9%), followed by short-course radiotherapy ± chemotherapy (7.6%). The use of neoadjuvant treatment for cancer of the upper third (15-11 cm) increased over time (31.5%vs 34.5%vs 38.6%, p = 0.0018). The complete regression rate slightly increased over time (15.6% vs 16% vs 18.5%; p = 0.0093); the proportion of patients with involved circumferential resection margins (CRM) went down from 8.2% to 7.3%and 5.5% (p = 0.0004). Neoadjuvant treatment significantly decreased positive CRM in lower third tumors (OR 0.71, 0.59–0.87, Cochrane-Mantel-Haenszel P = 0.0008). Most ypN0 patients also received adjuvant therapy. In MR-defined stage III patients, preoperative treatment was associated with significantly longer local-recurrence-free survival (p < 0.0001), and cancer-specific survival (p < 0.0001). The survival benefit was smaller in upper third cancers. Conclusion: There was an increasing trend and a potential overuse of neoadjuvant treatment in cancer of the upper rectum. Most ypN0 patients received postoperative treatment. Involvement of CRM in lower third tumors was reduced after neoadjuvant treatment. Stage III and MRcN + benefited the most

    Utjecaj toksičnosti metala na reprodukcijsku funkciju u muškaraca

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    A combination of genetic, environmental and lifestyle factors contributes to adverse effects on the reproductive health in men. Metals are pervasive in food, water, air, tobacco smoke, and alcoholic beverages. Experimental studies suggest that many metals have adverse effects on the male reproductive function. However, information about reproductive effects of human exposure to metals is scarce and/or inconsistent. This review summarises the information from epidemiological studies of the effects of metal exposure on reproductive function in men. Factors capable of affecting these relationships were identifi ed and discussed. A particular attention is given to the studies considering influence of concomitant exposure to various metals. These studies have generally confirmed that even moderate- to low-level exposure to lead affects certain reproductive parameters, and that exposure to cadmium affects the prostate function and serum testosterone levels. Adverse effects of mercury, manganese, chromium and arsenic on semen quality and altered serum hormone are less well documented. There is no clear evidence that boron exposure may impair reproductive health in men. Only a few studies have investigated reproductive effects of concomitant exposure to several metals and controlled for potential confounders. Future studies should consider the contribution of combined exposure to various metals and/or other factors that may influence individual susceptibility to reproductive health impairment in men.Postoje indikacije da kombinacija genetskih, okolišnih i čimbenika načina života pridonosi uočenom poremećaju reprodukcijskog zdravlja u muškaraca. Metali su široko rasprostranjeni u čovjekovu okolišu te u hrani, vodi, zraku, cigaretnom dimu i alkoholnim pićima. Rezultati eksperimentalnih istraživanja sugeriraju štetne učinke većine ispitivanih metala na mušku reprodukcijsku funkciju. Međutim, odgovarajuća su istraživanja u ljudi oskudna. Ovaj rad sažima rezultate dosadašnjih epidemioloških istraživanja o učincima izloženosti metalima na mušku reprodukcijsku funkciju. Poseban naglasak dan je istraživanjima koja su razmatrala utjecaj istodobne izloženosti različitim metalima uz čimbenike čovjekova načina života i njihovo međudjelovanje na reprodukcijske učinke. Objavljeni rezultati daju dovoljno dokaza o štetnom djelovanju olova i žive na neke reprodukcijske parametre te kadmija na poremećaj prostate i razinu testosterona u serumu, čak u uvjetima umjerene do niske razine izloženosti. Manje je dokaza o štetnom djelovanju na kvalitetu sjemena i razinu spolnih hormona nađeno za mangan. Podaci koji upućuju na moguće štetno djelovanje arsena ili kroma nisu dosljedni, dok o štetnom djelovanju bora na mušku reprodukcijsku funkciju nema jasnih podataka. Utjecaj potencijalno uzročnih varijabli uzet je u obzir samo u nekoliko radova. Stoga buduća istraživanja poremećaja reprodukcijskog zdravlja u muškaraca trebaju razmatrati doprinos istovremene izloženosti različitim metalima koji u kombinaciji s ostalim čimbenicima mogu utjecati na osobnu (pre)osjetljivost

    Molecular plant-plum pox virus interactions

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    Plum pox virus, the agent that causes sharka disease, is among the most important plant viral pathogens, affecting Prunus trees across the globe. The fabric of interactions that the virus is able to establish with the plant regulates its life cycle, including RNA uncoating, translation, replication, virion assembly, and movement. In addition, plant-virus interactions are strongly conditioned by host specificities, which determine infection outcomes, including resistance. This review attempts to summarize the latest knowledge regarding Plum pox virus–host interactions, giving a comprehensive overview of their relevance for viral infection and plant survival, including the latest advances in genetic engineering of resistant species.Work in the authors’ laboratory was funded by grants from the Ministerio de Ciencia, Innovación y Universidades (AEI-FEDER) BIO2016-80572-R and BIO2015-73900-JIN

    Plant viral proteases: Beyond the role of peptide cutters

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    Almost half of known plant viral species rely on proteolytic cleavages as key co-and post-translational modifications throughout their infection cycle. Most of these viruses encode their own endopeptidases, proteases with high substrate specificity that internally cleave large polyprotein precursors for the release of functional subunits. Processing of the polyprotein, however, is not an all-or-nothing process in which endopeptidases act as simple peptide cutters. On the contrary, spatial-temporal modulation of these polyprotein cleavage events is crucial for a successful viral infection. In this way, the processing of the polyprotein coordinates viral replication, assembly and movement, and has significant impact on pathogen fitness and virulence. In this mini-review, we give an overview of plant viral proteases emphasizing their importance during viral infections and the varied functionalities that result from their proteolytic activities.HS was supported by the China Scholarship Council; FP was supported by a post-doctoral fellowship from Academia Sinica. This work was funded by Grant No. BIO2016-80572-R and the FEDER program

    Sterol isomerase HYDRA1 interacts with RNA silencing suppressor P1b and restricts potyviral infection

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    Plants use RNA silencing as a strong defensive barrier against virus challenges, and viruses counteract this defence by using RNA silencing suppressors (RSSs). With the objective of identifying host factors helping either the plant or the virus in this interaction, we have performed a yeast two-hybrid screen using P1b, the RSS protein of the ipomovirus Cucumber vein yellowing virus (CVYV, family Potyviridae), as a bait. The C-8 sterol isomerase HYDRA1 (HYD1), an enzyme involved in isoprenoid biosynthesis and cell membrane biology, and required for RNA silencing, was isolated in this screen. The interaction between CVYV P1b and HYD1 was confirmed in planta by Bimolecular Fluorescence Complementation assays. We demonstrated that HYD1 negatively impacts the accumulation of CVYV P1b in an agroinfiltration assay. Moreover, expression of HYD1 inhibited the infection of the potyvirus Plum pox virus, especially when antiviral RNA silencing was boosted by high temperature or by coexpression of homologous sequences. Our results reinforce previous evidence highlighting the relevance of particular composition and structure of cellular membranes for RNA silencing and viral infection. We report a new interaction of an RSS protein from the Potyviridae family with a member of the isoprenoid biosynthetic pathway.FEDER Ministerio de Ciencia e Innovación. Grant Numbers: BIO2013-49053-R, BIO2015-73900-JIN, BIO2016-80572-

    The P1N-PISPO trans-Frame Gene of Sweet Potato Feathery Mottle Potyvirus Is Produced during Virus Infection and Functions as an RNA Silencing Suppressor

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    The positive-sense RNA genome of Sweet potato feathery mottle virus (SPFMV) (genus Potyvirus, family Potyviridae) contains a large open reading frame (ORF) of 3,494 codons translatable as a polyprotein and two embedded shorter ORFs in the-1 frame: PISPO, of 230 codons, and PIPO, of 66 codons, located in the P1 and P3 regions, respectively. PISPO is specific to some sweet potato-infecting potyviruses, while PIPO is present in all potyvirids. In SPFMV these two extra ORFs are preceded by conserved G2A6 motifs. We have shown recently that a polymerase slippage mechanism at these sites could produce transcripts bringing these ORFs in frame with the upstream polyprotein, thus leading to P1N-PISPO and P3N-PIPO products (B. Rodamilans, A. Valli, A. Mingot, D. San Leon, D. B. Baulcombe, J. J. Lopez-Moya, and J.A. Garcia, J Virol 89:6965-6967, 2015, doi:10.1128/JVI.00 337-15). Here, we demonstrate by liquid chromatography coupled to mass spectrometry that both P1 and P1N-PISPO are produced during viral infection and coexist in SPFMV-infected Ipomoea batatas plants. Interestingly, transient expression of SPFMV gene products coagroinfiltrated with a reporter gene in Nicotiana benthamiana revealed that P1N-PISPO acts as an RNA silencing suppressor, a role normally associated with HCPro in other potyviruses. Moreover, mutation of WG/GW motifs present in P1N-PISPO abolished its silencing suppression activity, suggesting that the function might require interaction with Argonaute components of the silencing machinery, as was shown for other viral suppressors. Altogether, our results reveal a further layer of complexity of the RNA silencing suppression activity within the Potyviridae familyThis work was funded by Mineco grants AGL2013-42537-R to J.J.L.-M. and BIO2013-49053-R to J.A.G. and by Plant KBBE PCIN-2013-056 to J.A.G. A.M. is a recipient of FPI fellowship BES-2011-045699. D.C.B. is the Royal Society Edward Penley Abraham Research Professor.Peer reviewe
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