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During a routine screening for G6PD deficiency in the Province of Matera (Southern Italy), an eleven-year-old boy was brought to our attention who had fever obviously caused by a viral infection, but who also had hepatosplenomegaly and haemoglobinuria. The boy had previously experienced two severe haemolytic attacks. At the age of six months severe haemolysis occurred after the ingestion of cooked fava beans. At the age of seven years, the haemolytic episode was very likely triggered by oral administration of co-trimoxazole. The G6PD activity level in erythrocyte lysate was clearly defective (25% of normal). The electrophoretic mobility of G6PD was 110% of normal. These data together with those obtained from biochemical and molecular characterisation allowed the variant to be identified as G6PD A(-). This is the first report of an association between the African type G6PD deficiency variant and favism.

Embryonic stem cells (ESCs) present a characteristic pluripotency heterogeneity correspondent to specific metastates. We recently demonstrated that retinoic acid (RA) induces an increase in a specific 2C-like metastate marked by target genes specific to the two-cell embryo stage in preimplantation. Prame (Preferentially expressed antigen in melanoma) is one of the principal actors of the pluripotency stage with a specific role in RA responsiveness. Additionally, PRAME is overexpressed in a variety of cancers, but its molecular functions are poorly understood. To further investigate Prame’s downstream targets, we used a chromatin immunoprecipitation sequencing (ChIP-seq) assay in RA-enriched 2C-like metastates and identified two specific target genes, Cdk8 and Cdkn2d, bound by Prame. These two targets, involved in cancer dedifferentiation and pluripotency, have been further validated in RA-resistant ESCs. Here, we observed for the first time that Prame controls the Cdk8 and Cdkn2d genes in ESCs after RA treatment, shedding light on the regulatory network behind the establishment of naïve pluripotency.

YB-1 is a multifunctional protein overexpressed in many types of cancer. It is a crucial oncoprotein that regulates cancer cell progression and proliferation. Ubiquitously expressed in human cells, YB-1 protein functions are strictly dependent on its subcellular localization. In the cytoplasm, where YB-1 is primarily localized, it regulates mRNA translation and stability. However, in response to stress stimuli and activation of PI3K and RSK signaling, YB-1 moves to the nucleus acting as a prosurvival factor. YB-1 is reported to regulate many cellular signaling pathways in different types of malignancies. Furthermore, several observations also suggest that YB-1 is a sensor of oxidative stress and DNA damage. Here we show that YB-1 reduces PTEN intracellular levels thus leading to PI3K/Akt pathway activation. Remarkably, PTEN reduction mediated by YB-1 overexpression can be observed in human immortalized keratinocytes and HEK293T cells and cannot be reversed by proteasome inhibition. Real-time PCR data indicate that YB-1 silencing up-regulates the PTEN mRNA level. Collectively, these observations indicate that YB-1 negatively controls PTEN at the transcript level and its overexpression could confer survival and proliferative advantage to PTEN proficient cancer cells.

The Y Box binding protein 1 (YB-1) belongs to the highly conserved Cold Shock Domain protein family and is a major component of messenger ribonucleoprotein particles (mRNPs) in various organisms and cells. Cold Shock proteins are multifunctional nucleic acids binding proteins involved in a variety of cellular functions. Biological activities of YB-1 range from the regulation of transcription, splicing and translation, to the orchestration of exosomal RNA content. The role of YB-1 in malignant cell transformation and fate transition is the subject of intensive investigation. Besides, emerging evidence indicates that YB-1 participates in several DNA damage repair pathways as a non-canonical DNA repair factor thus pointing out that the protein can allow cancer cells to evade conventional anticancer therapies and avoid cell death. Here, we will attempt to collect and summarize the current knowledge on this subject and provide the basis for further lines of inquiry.

Two new diterpenoids with tetrasubstituted 3-oxodihydrofuran substituents, named higginsianins D (1) and E (2), were isolated from the mycelium of the fungus Colletotrichum higginsianum grown in liquid culture. They were characterized as methyl 2-[6-hydroxy-5,8a-dimethyl-2-methylene-5-(4-methylpent-3-enyl)-decahydronaphthalen-1-ylmethyl]-4,5-dimethyl-3-oxo-2,3-dihydrofuran-2-carboxylate and its 21-epimer by using NMR, HRESIMS, and chemical methods. The relative configurations of higginsianins D and E, which did not afford crystals suitable for X-ray analysis, were determined by NOESY experiments and by comparison with NMR data of higginsianin B. The absolute configuration was established by comparison of experimental and calculated electronic circular dichroism data. The evaluation of 1 and 2 for antiproliferative activity against human A431 cells derived from epidermoid carcinoma and H1299 non-small-cell lung carcinoma cells revealed that 2 exhibited higher cytotoxic activity than 1, with an IC50 value of 1.0 μM against A431 cells. Remarkably, both 1 and 2 were almost ineffective against immortalized keratinocytes, used as a preneoplastic cell line model.

Cultured mouse embryonic stem cells are a heterogeneous population with diverse differentiation potential. In particular, the subpopulation marked by Zscan4 expression has high stem cell potency and shares with 2 cell stage preimplantation embryos both genetic and epigenetic mechanisms that orchestrate zygotic genome activation. Although embryonic de novo genome activation is known to rely on metabolites, a more extensive metabolic characterization is missing. Here we analyze the Zscan4(+) mouse stem cell metabolic phenotype associated with pluripotency maintenance and cell reprogramming. We show that Zscan4(+) cells have an oxidative and adaptable metabolism, which, on one hand, fuels a high bioenergetic demand and, on the other hand, provides intermediate metabolites for epigenetic reprogramming. Our findings enhance our understanding of the metastable Zscan4(+) stem cell state with potential applications in regenerative medicine.

Two new bioactive ophiobolan sestertepenoids, named drophiobiolins A and B (1 and 2) were isolated from Drechslera gigantea, a fungus proposed as a mycoherbicide for biocontrol of Digitaria sanguinalis. They were isolated together with ophiobolin A, the main metabolite, 6-epi-ophiobolin A, 3-anhydro-6-epi-ophiobolin A, and ophiobolin I. Drophiobolins A and B were characterized by NMR, HRESIMS, and chemical methods as 7-hydroxy-7-(6-hydroxy-6-methylheptan-2-yl)-1,9a-dimethyl-3-oxo-3,3a,6,6a,7,8,9,9a,10,10a-decahydrodicyclopenta [a,d][8]annulene-4-carbaldehyde and 6-(hydroxymethyl)-3?,9,10a-trimethyl-5?-(2-methylprop-1-en-1-yl)-3a,4,4?,5?,10,10a-hexahydro-1H,3?H-spiro[dicyclopenta[a,d] [8]annulene-3,2?-furan]-5,7(2H,9aH)-dione. The relative configuration of drophiobolins A and B, which did not afford crystals suitable for X-ray analysis, was determined by NOESY experiments, while the absolute configuration was assigned by comparison of their experimental and TDDFT calculated electronic circular dichroism (ECD) spectra. The phytotoxic activity of drophiobolins A and B was tested by leaf-puncture assay on cultivated (Lycopersicon esculentum L.), as well as on host (Digitaria sanguinalis L.) and nonhost (Chenopodium album L.) weed plants, compared to that of ophiobolin A. Both of the newly identified ophiobolins showed significant phytotoxicity. Drophiobolins A and B exhibited cytotoxicity against Hela B cells with an IC50 value of 10 ?M. However, they had a lesser or no effect against Hacat, H1299, and A431 cells when compared to that of ophiobolin A.

Up until the first half of the 20th century, silver found significant employment in medical applications, particularly in the healing of open wounds, thanks to its antibacterial and antifungal properties. Wound repair is a complex and dynamic biological process regulated by several pathways that cooperate to restore tissue integrity and homeostasis. To facilitate healing, injuries need to be promptly treated. Recently, the interest in alternatives to antibiotics has been raised given the widespread phenomenon of antibiotic resistance. Among these alternatives, the use of silver appears to be a valid option, so a resurgence in its use has been recently observed. In particular, in contrast to ionic silver, colloidal silver, a suspension of metallic silver particles, shows antibacterial activity displaying less or no toxicity. However, the human health risks associated with exposure to silver nanoparticles (NP) appear to be conflicted, and some studies have suggested that it could be toxic in different cellular contexts. These potentially harmful effects of silver NP depend on various parameters including NP size, which commonly range from 1 to 100 nm. In this study, we analyzed the effect of a colloidal silver preparation composed of very small and homogeneous nanoparticles of 0.62 nm size, smaller than those previously tested. We found no adverse effect on the cell proliferation of HaCaT cells, even at high NP concentration. Time-lapse microscopy and indirect immunofluorescence experiments demonstrated that this preparation of colloidal silver strongly increased cell migration, re-modeled the cytoskeleton, and caused recruitment of E-cadherin at cell-cell junctions of human cultured keratinocytes.

Crinum biflorum Rottb. (syn. Crinum distichum) is an Amaryllidaceae plant used in African traditional medicine but very few studies have been performed on this species from a chemical and applicative point of view. Bulbs of C. biflorum, collected in Senegal, were extracted with ethanol by Soxhlet and the corresponding organic extract was purified using chromatographic methods. The pure compounds were chemically characterized by spectroscopic techniques (1D and 2D 1H and 13C NMR, HR MS and ECD) and X-ray analysis. Four homoisoflavonoids (1–4) and one alkylamide (5) were isolated and characterized as 5,6,7-trimethoxy-3-(4-hydroxybenzyl)chroman-4-one (1), as 3-hydroxy-5,6,7-trimethoxy-3-(4-hydroxybenzyl)chroman-4-one (2), as 3-hydroxy-5,6,7-trimethoxy-3-(4-methoxybenzyl)chroman-4-one (3) and as 5,6,7-trimethoxy-3-(4-methoxybenzyl)chroman-4-one (4), and the alkylamide as (E)-N-(4-hydroxyphenethyl)-3-(4-hydroxyphenyl)acrylamide (5), commonly named N-p-coumaroyltyramine. The relative configuration of compound 1 was verified thanks to the X-ray analysis which also allowed us to confirm its racemic nature. The absolute configurations of compounds 2 and 3 were assigned by comparing their ECD spectra with those previously reported for urgineanins A and B. Flavanoids 1, 3 and 4 showed promising anticancer properties being cytotoxic at low micromolar concentrations towards HeLa and A431 human cancer cell lines. The N-p-coumaroyltyramine (5) was selectively toxic to A431 and HeLa cancer cells while it protected immortalized HaCaT cells against oxidative stress induced by hydrogen peroxide. Compounds 1–4 also inhibited acetylcholinesterase activity with compound 3 being the most potent. The anti-amylase and the strong anti-glucosidase activity of compound 5 were confirmed. Our results show that C. biflorum produces compounds of therapeutic interest with anti-diabetic, anti-tumoral and anti-acetylcholinesterase properties.

The fungal pathogens Cochliobolus australiensis and Pyricularia grisea have recently been isolated from diseased leaves of buffelgrass (Cenchrus ciliaris) in its North American range, and their ability to produce phytotoxic metabolites that could potentially be used as natural herbicides against this invasive weed was investigated. Fourteen secondary metabolites obtained from in vitro cultures of these two pathogens were tested by leaf puncture assay on the host plant at different concentrations. Radicinin and (10S, 11S)-epi-pyriculol proved to be the most promising compounds. Thus, their phytotoxic activity was also evaluated on non-host indigenous plants. Radicinin demonstrated high target-specific toxicity on buffelgrass, low toxicity to native plants, and no teratogenic, sub-lethal, or lethal effects on zebrafish (Brachydanio rerio) embryos. It is now under consideration for the development of a target-specific bioherbicide to be used against buffelgrass in natural systems where synthetic herbicides cause excessive damage to native plants.

Three-dimensional models of exoinulinase from Bacillus stearothermophilus and endoinulinase from Aspergillus niger were built up by means of homology modeling. The crystal structure of exoinulinase from Aspergillus awamori was used as a template, which is the sole structure of inulinase resolved so far. Docking and molecular dynamics simulations were performed to investigate the differences between the two inulinases in terms of substrate selectivity. The analysis of the structural differences between the two inulinases provided the basis for the explanation of their different regio-selectivity and for the understanding of enzyme-substrate interactions. Surface analysis was performed to point out structural features that can affect the efficiency of enzymes also after immobilization. The computational analysis of the three-dimensional models proved to be an effective tool for acquiring information and allowed to formulate an optimal immobilized biocatalyst even more active that the native one, thus enabling the full exploitation of the catalytic potential of these enzymes.

Background and objectives Evidence of abnormal color vision processing in migraine comes from observation of positive symptoms during visual aura, effects of strong color contrast triggering attacks and of colored-spectacles reducing migraine frequency. Although the central or peripheral basis of such color misperception remains unclear, several authors reported a selective deficit of shortwavelength cones (S-cones) [1]. Sound-induced flash illusions (SIFI) are a simple way to describe visual distorsion induced by acoustic perception. SIFI critically depend on excitability of primary visual cortex (V1) as they are reduced by facilitatory anodal transcranial direct current stimulation (tDCS) over V1 in healthy subjects [2]. We observed diminished SIFI in episodic migraine patients, especially in those with aura (MA) and during the attack [3] in agreement with the hypothesis of visual cortex hyperexcitability. Aim of the present study was to explore the potential correlation between cones dysfunction (evaluated by colorimetric scales) and visual cortex hyperexcitability (tested by SIFI) in episodic migraine without aura patients (MoA). Materials and methods Twenty-two MoA patients (4 M; mean age 35.8±11.1 years) and 12 unimpaired healthy volunteers with no family history of migraine (9 M; mean age 27.7±13.2 years) were enrolled. Migraine patients were tested interictally. None of the patients enrolled had taken any prophylactic drug during the 3 months prior to the