Investigating the antiparasitic potential of the marine sesquiterpene avarone, its reduced form avarol, and the novel semisynthetic thiazinoquinone analogue thiazoavarone

The chemical analysis of the sponge Dysidea avara afforded the known sesquiterpene quinone avarone, along with its reduced form avarol. To further explore the role of the thiazinoquinone scaffold as an antiplasmodial, antileishmanial and antischistosomal agent, we converted the quinone avarone into the thiazinoquinone derivative thiazoavarone. The semisynthetic compound, as well as the natural metabolites avarone and avarol, were pharmacologically investigated in order to assess their antiparasitic properties against sexual and asexual stages of Plasmodium falciparum, larval and adult developmental stages of Schistosomamansoni (eggs included), and also against promastigotes and amastigotes of Leishmania infantum and Leishmania tropica. Furthermore, in depth computational studies including density functional theory (DFT) calculations were performed. A toxic semiquinone radical species which can be produced starting both from quinone- and hydroquinone-based compounds could mediate the anti-parasitic effects of the tested compounds

EDA2R Is Associated with Androgenetic Alopecia

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Longitudinal study on low-dose aspirin versus placebo administration in silent brain infarcts: the silence study

Background. We investigated low-dose aspirin (ASA) efficacy and safety in subjects with silent brain infarcts (SBIs) in preventing new cerebrovascular (CVD) events as well as cognitive impairment. Methods. We included subjects aged ≥45 years, with at least one SBI and no previous CVD. Subjects were followed up to 4 years assessing CVD and SBI incidence as primary endpoint and as secondary endpoints: (a) cardiovascular and adverse events and (b) cognitive impairment. Results. Thirty-six subjects received ASA while 47 were untreated. Primary endpoint occurred in 9 controls (19.1%) versus 2 (5.6%) in the ASA group (p=0.10). Secondary endpoints did not differ in the two groups. Only baseline leukoaraiosis predicts primary [OR 5.4 (95%CI 1.3-22.9, p=0.022)] and secondary endpoint-A [3.2 (95%CI 1.1-9.6, p=0.040)] occurrence. Conclusions. These data show an increase of new CVD events in the untreated group. Despite the study limitations, SBI seems to be a negative prognostic factor and ASA preventive treatment might improve SBI prognosis. EU Clinical trial is registered with EudraCT Number: 2005-000996-16; Sponsor Protocol Number: 694/30.06.04

Cooperative Binding of the Cationic Porphyrin Tris-T4 Enhances Catalytic Activity of 20S Proteasome Unveiling a Complex Distribution of Functional States

The present study provides new evidence that cationic porphyrins may be considered as tunable platforms to interfere with the structural "key code" present on the 20S proteasome α-rings and, by consequence, with its catalytic activity. Here, we describe the functional and conformational effects on the 20S proteasome induced by the cooperative binding of the tri-cationic 5-(phenyl)-10,15,20-(tri N-methyl-4-pyridyl) porphyrin (Tris-T4). Our integrated kinetic, NMR, and in silico analysis allowed us to disclose a complex effect on the 20S catalytic activity depending on substrate/porphyrin concentration. The analysis of the kinetic data shows that Tris-T4 shifts the relative populations of the multiple interconverting 20S proteasome conformations leading to an increase in substrate hydrolysis by an allosteric pathway. Based on our Tris-T4/h20S interaction model, Tris-T4 is able to affect gating dynamics and substrate hydrolysis by binding to an array of negatively charged and hydrophobic residues present on the protein surface involved in the 20S molecular activation by the regulatory proteins (RPs). Accordingly, despite the fact that Tris-T4 also binds to the α3ΔN mutant, allosteric modulation is not observed since the molecular mechanism connecting gate dynamics with substrate hydrolysis is impaired. We envisage that the dynamic view of the 20S conformational equilibria, activated through cooperative Tris-T4 binding, may work as a simplified model for a better understanding of the intricate network of 20S conformational/functional states that may be mobilized by exogenous ligands, paving the way for the development of a new generation of proteasome allosteric modulators

Targeting CXCR4 reverts the suppressive activity of T-regulatory cells in renal cancer

With the intent to identify biomarkers in renal cell carcinoma (RCC) the functional status of T-regulatory cells (Tregs) was investigated in primary RCC. Tregs were isolated from tumoral-(TT), peritumoral tissue-(PT) and peripheral blood-(PB) of 42 primary RCC patients and function evaluated through effector T cells (Teff) proliferation, cytokines release and demethylation of Treg Specific Region (TSDR). The highest value of Tregs was detected in TT with the uppermost amount of effector-Tregs-(CD4+CD25hiFOXP3hiCD45RA-). PB-RCC Tregs efficiently suppress Teff proliferation compared to healthy donor (HD)-Tregs and, at the intrapatient evaluation, TT-derived Tregs were the most suppressive. Higher demethylation TSDR was detected in TT- and PB-RCC Tregs vs HD-Tregs (P <0,001). CXCR4 is highly expressed on Tregs, thus we wished to modulate Tregs function through CXCR4 inhibition. CXCR4 antagonism, elicited by a new peptidic antagonist, Peptide-R29, efficiently reversed Tregs suppression of Teff proliferation. Thus Tregs functional evaluation precisely reflects Tregs status and may be a reliable biomarker of tumoral immune response. In addition, treatment with CXCR4 antagonist, impairing Tregs function, could improve the anticancer immune response, in combination with conventional therapy and/or immunotherapy such as checkpoints inhibitors

The maize fused leaves1 (fdl1) gene controls organ separation in the embryo and seedling shoot and promotes coleoptile opening

The fdl1-1 mutation, caused by an Enhancer/Suppressor mutator (En/Spm) element insertion located in the third exon of the gene, identifies a novel gene encoding ZmMYB94, a transcription factor of the R2R3-MYB subfamily. The fdl1 gene was isolated through co-segregation analysis, whereas proof of gene identity was obtained using an RNAi strategy that conferred less severe, but clearly recognizable specific mutant traits on seedlings. Fdl1 is involved in the regulation of cuticle deposition in young seedlings as well as in the establishment of a regular pattern of epicuticular wax deposition on the epidermis of young leaves. Lack of Fdl1 action also correlates with developmental defects, such as delayed germination and seedling growth, abnormal coleoptile opening and presence of curly leaves showing areas of fusion between the coleoptile and the first leaf or between the first and the second leaf. The expression profile of ZmMYB94 mRNA\u2014determined by quantitative RT-PCR\u2014 overlaps the pattern of mutant phenotypic expression and is confined to a narrow developmental window. High expression was observed in the embryo, in the seedling coleoptile and in the first two leaves, whereas RNA level, as well as phenotypic defects, decreases at the third leaf stage. Interestingly several of the Arabidopsis MYB genes most closely related to ZmMYB94 are also involved in the activation of cuticular wax biosynthesis, suggesting deep conservation of regulatory processes related to cuticular wax deposition between monocots and dicots

Phenotype reversion as “natural gene therapy” in Fanconi anemia by a gene conversion event

Somatic mosaicism appears as a recurrent phenomenon among patients suffering from Fanconi anemia (FA), but its direct prognostic significance mostly remains an open question. The clinical picture of FA mosaic subjects could indeed vary from just mild features to severe hematologic failure. Here, we illustrate the case of a proband whose FA familiarity, modest signs (absence of hematological anomalies and fertility issues), and chromosome fragility test transition to negative overtime were suggestive of somatic mosaicism. In line with this hypothesis, genetic testing on patient’s peripheral blood and buccal swab reported the presence of the only FANCA paternal variant (FANCA:c.2638C&gt;T, p. Arg880*) and of both parental alleles (the additional FANCA:c.3164G&gt;A, p. Arg1055Gln), respectively. Moreover, the SNP analysis performed on the same biological specimens allowed us to attribute the proband’s mosaicism status to a possible gene conversion mechanism. Our case clearly depicts the positive association between somatic mosaicism and the proband's favorable clinical course due to the occurrence of the reversion event at the hematopoietic stem cell level. Since this condition concerns only a limited subgroup of FA individuals, the accurate evaluation of the origin and extent of clonality would be key to steer clinicians toward the most appropriate therapeutic decision for their FA mosaic patients

Clinical management of HCV carriers with normal aminotransferase levels.

An ad hoc committee appointed by the Italian Association for the Study of the Liver (AISF) proposed these Practice Guidelines for the management of HCV carriers with persistently normal aminotransferase levels. Only stringent ALT determinations will make it possible to distinguish these subjects from those in temporary biochemical remission. The overall prevalence in Italy has been estimated between 1.5 and 10.6\%. HCV RNA quantitation and genotype determination are not predictors of the presence and severity of liver damage nor correlate with the outcome of the disease, and should not be used in clinical practice for the management and surveillance of HCV carriers with normal ALT. Only a minority of HCV carriers with normal ALT levels show a normal morphological picture (true 'healthy carriers'). Disease activity is mild in most cases; fibrosis is generally mild and cirrhosis is very rare. Histological activity, as monitored by sequential liver biopsies, seems to have very slow evolution. HCV carriers should not undergo liver biopsy on a routine basis. Liver biopsy can be reasonably proposed only in selected cases. Until the results of studies with PEG interferon plus ribavirin are available, HCV carriers should not receive antiviral treatment outside controlled experimental studies